nsz Git - cparser/blob - parser.c

   1 /*
   2  * This file is part of cparser.
   3  * Copyright (C) 2007-2008 Matthias Braun <matze@braunis.de>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  18  * 02111-1307, USA.
  19  */
  20 #include <config.h>
  21
  22 #include <assert.h>
  23 #include <stdarg.h>
  24 #include <stdbool.h>
  25
  26 #include "parser.h"
  27 #include "diagnostic.h"
  28 #include "format_check.h"
  29 #include "lexer.h"
  30 #include "symbol_t.h"
  31 #include "token_t.h"
  32 #include "types.h"
  33 #include "type_t.h"
  34 #include "type_hash.h"
  35 #include "ast_t.h"
  36 #include "lang_features.h"
  37 #include "warning.h"
  38 #include "adt/bitfiddle.h"
  39 #include "adt/error.h"
  40 #include "adt/array.h"
  41
  42 /** if wchar_t is equal to unsigned short. */
  43 bool opt_short_wchar_t =
  44 #ifdef _WIN32
  45         true;
  46 #else
  47         false;
  48 #endif
  49
  50 //#define PRINT_TOKENS
  51 #define MAX_LOOKAHEAD 2
  52
  53 typedef struct {
  54         declaration_t *old_declaration;
  55         symbol_t      *symbol;
  56         unsigned short namespc;
  57 } stack_entry_t;
  58
  59 typedef struct argument_list_t argument_list_t;
  60 struct argument_list_t {
  61         long              argument;
  62         argument_list_t  *next;
  63 };
  64
  65 typedef struct gnu_attribute_t gnu_attribute_t;
  66 struct gnu_attribute_t {
  67         gnu_attribute_kind_t kind;           /**< The kind of the GNU attribute. */
  68         gnu_attribute_t     *next;
  69         bool                 invalid;        /**< Set if this attribute had argument errors, */
  70         bool                 have_arguments; /**< True, if this attribute has arguments. */
  71         union {
  72                 size_t              value;
  73                 string_t            string;
  74                 atomic_type_kind_t  akind;
  75                 long                argument;  /**< Single argument. */
  76                 argument_list_t    *arguments; /**< List of argument expressions. */
  77         } u;
  78 };
  79
  80 typedef struct declaration_specifiers_t  declaration_specifiers_t;
  81 struct declaration_specifiers_t {
  82         source_position_t  source_position;
  83         unsigned char      declared_storage_class;
  84         unsigned char      alignment;         /**< Alignment, 0 if not set. */
  85         unsigned int       is_inline : 1;
  86         unsigned int       deprecated : 1;
  87         decl_modifiers_t   modifiers;         /**< declaration modifiers */
  88         gnu_attribute_t   *gnu_attributes;    /**< list of GNU attributes */
  89         const char        *deprecated_string; /**< can be set if declaration was marked deprecated. */
  90         symbol_t          *get_property_sym;  /**< the name of the get property if set. */
  91         symbol_t          *put_property_sym;  /**< the name of the put property if set. */
  92         type_t            *type;
  93 };
  94
  95 /**
  96  * An environment for parsing initializers (and compound literals).
  97  */
  98 typedef struct parse_initializer_env_t {
  99         type_t        *type;        /**< the type of the initializer. In case of an
 100                                          array type with unspecified size this gets
 101                                          adjusted to the actual size. */
 102         declaration_t *declaration; /**< the declaration that is initialized if any */
 103         bool           must_be_constant;
 104 } parse_initializer_env_t;
 105
 106 typedef declaration_t* (*parsed_declaration_func) (declaration_t *declaration, bool is_definition);
 107
 108 static token_t             token;
 109 static token_t             lookahead_buffer[MAX_LOOKAHEAD];
 110 static int                 lookahead_bufpos;
 111 static stack_entry_t      *environment_stack = NULL;
 112 static stack_entry_t      *label_stack       = NULL;
 113 static scope_t            *global_scope      = NULL;
 114 static scope_t            *scope             = NULL;
 115 static declaration_t      *last_declaration  = NULL;
 116 static declaration_t      *current_function  = NULL;
 117 static declaration_t      *current_init_decl = NULL;
 118 static switch_statement_t *current_switch    = NULL;
 119 static statement_t        *current_loop      = NULL;
 120 static statement_t        *current_parent    = NULL;
 121 static ms_try_statement_t *current_try       = NULL;
 122 static goto_statement_t   *goto_first        = NULL;
 123 static goto_statement_t   *goto_last         = NULL;
 124 static label_statement_t  *label_first       = NULL;
 125 static label_statement_t  *label_last        = NULL;
 126 static translation_unit_t *unit              = NULL;
 127 static struct obstack      temp_obst;
 128
 129 #define PUSH_PARENT(stmt)                          \
 130         statement_t *const prev_parent = current_parent; \
 131         current_parent = (stmt);
 132 #define POP_PARENT ((void)(current_parent = prev_parent))
 133
 134 static source_position_t null_position = { NULL, 0 };
 135
 136 /* symbols for Microsoft extended-decl-modifier */
 137 static const symbol_t *sym_align      = NULL;
 138 static const symbol_t *sym_allocate   = NULL;
 139 static const symbol_t *sym_dllimport  = NULL;
 140 static const symbol_t *sym_dllexport  = NULL;
 141 static const symbol_t *sym_naked      = NULL;
 142 static const symbol_t *sym_noinline   = NULL;
 143 static const symbol_t *sym_noreturn   = NULL;
 144 static const symbol_t *sym_nothrow    = NULL;
 145 static const symbol_t *sym_novtable   = NULL;
 146 static const symbol_t *sym_property   = NULL;
 147 static const symbol_t *sym_get        = NULL;
 148 static const symbol_t *sym_put        = NULL;
 149 static const symbol_t *sym_selectany  = NULL;
 150 static const symbol_t *sym_thread     = NULL;
 151 static const symbol_t *sym_uuid       = NULL;
 152 static const symbol_t *sym_deprecated = NULL;
 153 static const symbol_t *sym_restrict   = NULL;
 154 static const symbol_t *sym_noalias    = NULL;
 155
 156 /** The token anchor set */
 157 static unsigned char token_anchor_set[T_LAST_TOKEN];
 158
 159 /** The current source position. */
 160 #define HERE (&token.source_position)
 161
 162 static type_t *type_valist;
 163
 164 static statement_t *parse_compound_statement(bool inside_expression_statement);
 165 static statement_t *parse_statement(void);
 166
 167 static expression_t *parse_sub_expression(unsigned precedence);
 168 static expression_t *parse_expression(void);
 169 static type_t       *parse_typename(void);
 170
 171 static void parse_compound_type_entries(declaration_t *compound_declaration);
 172 static declaration_t *parse_declarator(
 173                 const declaration_specifiers_t *specifiers, bool may_be_abstract);
 174 static declaration_t *record_declaration(declaration_t *declaration, bool is_definition);
 175
 176 static void semantic_comparison(binary_expression_t *expression);
 177
 178 #define STORAGE_CLASSES     \
 179         case T_typedef:         \
 180         case T_extern:          \
 181         case T_static:          \
 182         case T_auto:            \
 183         case T_register:        \
 184         case T___thread:
 185
 186 #define TYPE_QUALIFIERS     \
 187         case T_const:           \
 188         case T_restrict:        \
 189         case T_volatile:        \
 190         case T_inline:          \
 191         case T__forceinline:    \
 192         case T___attribute__:
 193
 194 #ifdef PROVIDE_COMPLEX
 195 #define COMPLEX_SPECIFIERS  \
 196         case T__Complex:
 197 #define IMAGINARY_SPECIFIERS \
 198         case T__Imaginary:
 199 #else
 200 #define COMPLEX_SPECIFIERS
 201 #define IMAGINARY_SPECIFIERS
 202 #endif
 203
 204 #define TYPE_SPECIFIERS       \
 205         case T_void:              \
 206         case T_char:              \
 207         case T_short:             \
 208         case T_int:               \
 209         case T_long:              \
 210         case T_float:             \
 211         case T_double:            \
 212         case T_signed:            \
 213         case T_unsigned:          \
 214         case T__Bool:             \
 215         case T_struct:            \
 216         case T_union:             \
 217         case T_enum:              \
 218         case T___typeof__:        \
 219         case T___builtin_va_list: \
 220         case T__declspec:         \
 221         COMPLEX_SPECIFIERS        \
 222         IMAGINARY_SPECIFIERS
 223
 224 #define DECLARATION_START   \
 225         STORAGE_CLASSES         \
 226         TYPE_QUALIFIERS         \
 227         TYPE_SPECIFIERS
 228
 229 #define TYPENAME_START      \
 230         TYPE_QUALIFIERS         \
 231         TYPE_SPECIFIERS
 232
 233 /**
 234  * Allocate an AST node with given size and
 235  * initialize all fields with zero.
 236  */
 237 static void *allocate_ast_zero(size_t size)
 238 {
 239         void *res = allocate_ast(size);
 240         memset(res, 0, size);
 241         return res;
 242 }
 243
 244 static declaration_t *allocate_declaration_zero(void)
 245 {
 246         declaration_t *declaration = allocate_ast_zero(sizeof(declaration_t));
 247         declaration->type      = type_error_type;
 248         declaration->alignment = 0;
 249         return declaration;
 250 }
 251
 252 /**
 253  * Returns the size of a statement node.
 254  *
 255  * @param kind  the statement kind
 256  */
 257 static size_t get_statement_struct_size(statement_kind_t kind)
 258 {
 259         static const size_t sizes[] = {
 260                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 261                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 262                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 263                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 264                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 265                 [STATEMENT_IF]          = sizeof(if_statement_t),
 266                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 267                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 268                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 269                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 270                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 271                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 272                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 273                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 274                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 275                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 276                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 277                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 278                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 279         };
 280         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 281         assert(sizes[kind] != 0);
 282         return sizes[kind];
 283 }
 284
 285 /**
 286  * Returns the size of an expression node.
 287  *
 288  * @param kind  the expression kind
 289  */
 290 static size_t get_expression_struct_size(expression_kind_t kind)
 291 {
 292         static const size_t sizes[] = {
 293                 [EXPR_INVALID]                 = sizeof(expression_base_t),
 294                 [EXPR_REFERENCE]               = sizeof(reference_expression_t),
 295                 [EXPR_CONST]                   = sizeof(const_expression_t),
 296                 [EXPR_CHARACTER_CONSTANT]      = sizeof(const_expression_t),
 297                 [EXPR_WIDE_CHARACTER_CONSTANT] = sizeof(const_expression_t),
 298                 [EXPR_STRING_LITERAL]          = sizeof(string_literal_expression_t),
 299                 [EXPR_WIDE_STRING_LITERAL]     = sizeof(wide_string_literal_expression_t),
 300                 [EXPR_COMPOUND_LITERAL]        = sizeof(compound_literal_expression_t),
 301                 [EXPR_CALL]                    = sizeof(call_expression_t),
 302                 [EXPR_UNARY_FIRST]             = sizeof(unary_expression_t),
 303                 [EXPR_BINARY_FIRST]            = sizeof(binary_expression_t),
 304                 [EXPR_CONDITIONAL]             = sizeof(conditional_expression_t),
 305                 [EXPR_SELECT]                  = sizeof(select_expression_t),
 306                 [EXPR_ARRAY_ACCESS]            = sizeof(array_access_expression_t),
 307                 [EXPR_SIZEOF]                  = sizeof(typeprop_expression_t),
 308                 [EXPR_ALIGNOF]                 = sizeof(typeprop_expression_t),
 309                 [EXPR_CLASSIFY_TYPE]           = sizeof(classify_type_expression_t),
 310                 [EXPR_FUNCNAME]                = sizeof(funcname_expression_t),
 311                 [EXPR_BUILTIN_SYMBOL]          = sizeof(builtin_symbol_expression_t),
 312                 [EXPR_BUILTIN_CONSTANT_P]      = sizeof(builtin_constant_expression_t),
 313                 [EXPR_BUILTIN_PREFETCH]        = sizeof(builtin_prefetch_expression_t),
 314                 [EXPR_OFFSETOF]                = sizeof(offsetof_expression_t),
 315                 [EXPR_VA_START]                = sizeof(va_start_expression_t),
 316                 [EXPR_VA_ARG]                  = sizeof(va_arg_expression_t),
 317                 [EXPR_STATEMENT]               = sizeof(statement_expression_t),
 318         };
 319         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 320                 return sizes[EXPR_UNARY_FIRST];
 321         }
 322         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 323                 return sizes[EXPR_BINARY_FIRST];
 324         }
 325         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 326         assert(sizes[kind] != 0);
 327         return sizes[kind];
 328 }
 329
 330 /**
 331  * Allocate a statement node of given kind and initialize all
 332  * fields with zero.
 333  */
 334 static statement_t *allocate_statement_zero(statement_kind_t kind)
 335 {
 336         size_t       size = get_statement_struct_size(kind);
 337         statement_t *res  = allocate_ast_zero(size);
 338
 339         res->base.kind   = kind;
 340         res->base.parent = current_parent;
 341         return res;
 342 }
 343
 344 /**
 345  * Allocate an expression node of given kind and initialize all
 346  * fields with zero.
 347  */
 348 static expression_t *allocate_expression_zero(expression_kind_t kind)
 349 {
 350         size_t        size = get_expression_struct_size(kind);
 351         expression_t *res  = allocate_ast_zero(size);
 352
 353         res->base.kind = kind;
 354         res->base.type = type_error_type;
 355         return res;
 356 }
 357
 358 /**
 359  * Creates a new invalid expression.
 360  */
 361 static expression_t *create_invalid_expression(void)
 362 {
 363         expression_t *expression         = allocate_expression_zero(EXPR_INVALID);
 364         expression->base.source_position = token.source_position;
 365         return expression;
 366 }
 367
 368 /**
 369  * Creates a new invalid statement.
 370  */
 371 static statement_t *create_invalid_statement(void)
 372 {
 373         statement_t *statement          = allocate_statement_zero(STATEMENT_INVALID);
 374         statement->base.source_position = token.source_position;
 375         return statement;
 376 }
 377
 378 /**
 379  * Allocate a new empty statement.
 380  */
 381 static statement_t *create_empty_statement(void)
 382 {
 383         statement_t *statement          = allocate_statement_zero(STATEMENT_EMPTY);
 384         statement->base.source_position = token.source_position;
 385         return statement;
 386 }
 387
 388 /**
 389  * Returns the size of a type node.
 390  *
 391  * @param kind  the type kind
 392  */
 393 static size_t get_type_struct_size(type_kind_t kind)
 394 {
 395         static const size_t sizes[] = {
 396                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
 397                 [TYPE_COMPLEX]         = sizeof(complex_type_t),
 398                 [TYPE_IMAGINARY]       = sizeof(imaginary_type_t),
 399                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
 400                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
 401                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
 402                 [TYPE_ENUM]            = sizeof(enum_type_t),
 403                 [TYPE_FUNCTION]        = sizeof(function_type_t),
 404                 [TYPE_POINTER]         = sizeof(pointer_type_t),
 405                 [TYPE_ARRAY]           = sizeof(array_type_t),
 406                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
 407                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
 408                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
 409         };
 410         assert(sizeof(sizes) / sizeof(sizes[0]) == (int) TYPE_TYPEOF + 1);
 411         assert(kind <= TYPE_TYPEOF);
 412         assert(sizes[kind] != 0);
 413         return sizes[kind];
 414 }
 415
 416 /**
 417  * Allocate a type node of given kind and initialize all
 418  * fields with zero.
 419  *
 420  * @param kind             type kind to allocate
 421  * @param source_position  the source position of the type definition
 422  */
 423 static type_t *allocate_type_zero(type_kind_t kind, const source_position_t *source_position)
 424 {
 425         size_t  size = get_type_struct_size(kind);
 426         type_t *res  = obstack_alloc(type_obst, size);
 427         memset(res, 0, size);
 428
 429         res->base.kind            = kind;
 430         res->base.source_position = *source_position;
 431         return res;
 432 }
 433
 434 /**
 435  * Returns the size of an initializer node.
 436  *
 437  * @param kind  the initializer kind
 438  */
 439 static size_t get_initializer_size(initializer_kind_t kind)
 440 {
 441         static const size_t sizes[] = {
 442                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 443                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 444                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 445                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 446                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 447         };
 448         assert(kind < sizeof(sizes) / sizeof(*sizes));
 449         assert(sizes[kind] != 0);
 450         return sizes[kind];
 451 }
 452
 453 /**
 454  * Allocate an initializer node of given kind and initialize all
 455  * fields with zero.
 456  */
 457 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 458 {
 459         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 460         result->kind          = kind;
 461
 462         return result;
 463 }
 464
 465 /**
 466  * Free a type from the type obstack.
 467  */
 468 static void free_type(void *type)
 469 {
 470         obstack_free(type_obst, type);
 471 }
 472
 473 /**
 474  * Returns the index of the top element of the environment stack.
 475  */
 476 static size_t environment_top(void)
 477 {
 478         return ARR_LEN(environment_stack);
 479 }
 480
 481 /**
 482  * Returns the index of the top element of the label stack.
 483  */
 484 static size_t label_top(void)
 485 {
 486         return ARR_LEN(label_stack);
 487 }
 488
 489 /**
 490  * Return the next token.
 491  */
 492 static inline void next_token(void)
 493 {
 494         token                              = lookahead_buffer[lookahead_bufpos];
 495         lookahead_buffer[lookahead_bufpos] = lexer_token;
 496         lexer_next_token();
 497
 498         lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
 499
 500 #ifdef PRINT_TOKENS
 501         print_token(stderr, &token);
 502         fprintf(stderr, "\n");
 503 #endif
 504 }
 505
 506 /**
 507  * Return the next token with a given lookahead.
 508  */
 509 static inline const token_t *look_ahead(int num)
 510 {
 511         assert(num > 0 && num <= MAX_LOOKAHEAD);
 512         int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
 513         return &lookahead_buffer[pos];
 514 }
 515
 516 /**
 517  * Adds a token to the token anchor set (a multi-set).
 518  */
 519 static void add_anchor_token(int token_type)
 520 {
 521         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 522         ++token_anchor_set[token_type];
 523 }
 524
 525 static int save_and_reset_anchor_state(int token_type)
 526 {
 527         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 528         int count = token_anchor_set[token_type];
 529         token_anchor_set[token_type] = 0;
 530         return count;
 531 }
 532
 533 static void restore_anchor_state(int token_type, int count)
 534 {
 535         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 536         token_anchor_set[token_type] = count;
 537 }
 538
 539 /**
 540  * Remove a token from the token anchor set (a multi-set).
 541  */
 542 static void rem_anchor_token(int token_type)
 543 {
 544         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 545         --token_anchor_set[token_type];
 546 }
 547
 548 static bool at_anchor(void)
 549 {
 550         if (token.type < 0)
 551                 return false;
 552         return token_anchor_set[token.type];
 553 }
 554
 555 /**
 556  * Eat tokens until a matching token is found.
 557  */
 558 static void eat_until_matching_token(int type)
 559 {
 560         int end_token;
 561         switch (type) {
 562                 case '(': end_token = ')';  break;
 563                 case '{': end_token = '}';  break;
 564                 case '[': end_token = ']';  break;
 565                 default:  end_token = type; break;
 566         }
 567
 568         unsigned parenthesis_count = 0;
 569         unsigned brace_count       = 0;
 570         unsigned bracket_count     = 0;
 571         while (token.type        != end_token ||
 572                parenthesis_count != 0         ||
 573                brace_count       != 0         ||
 574                bracket_count     != 0) {
 575                 switch (token.type) {
 576                 case T_EOF: return;
 577                 case '(': ++parenthesis_count; break;
 578                 case '{': ++brace_count;       break;
 579                 case '[': ++bracket_count;     break;
 580
 581                 case ')':
 582                         if (parenthesis_count > 0)
 583                                 --parenthesis_count;
 584                         goto check_stop;
 585
 586                 case '}':
 587                         if (brace_count > 0)
 588                                 --brace_count;
 589                         goto check_stop;
 590
 591                 case ']':
 592                         if (bracket_count > 0)
 593                                 --bracket_count;
 594 check_stop:
 595                         if (token.type        == end_token &&
 596                             parenthesis_count == 0         &&
 597                             brace_count       == 0         &&
 598                             bracket_count     == 0)
 599                                 return;
 600                         break;
 601
 602                 default:
 603                         break;
 604                 }
 605                 next_token();
 606         }
 607 }
 608
 609 /**
 610  * Eat input tokens until an anchor is found.
 611  */
 612 static void eat_until_anchor(void)
 613 {
 614         if (token.type == T_EOF)
 615                 return;
 616         while (token_anchor_set[token.type] == 0) {
 617                 if (token.type == '(' || token.type == '{' || token.type == '[')
 618                         eat_until_matching_token(token.type);
 619                 if (token.type == T_EOF)
 620                         break;
 621                 next_token();
 622         }
 623 }
 624
 625 static void eat_block(void)
 626 {
 627         eat_until_matching_token('{');
 628         if (token.type == '}')
 629                 next_token();
 630 }
 631
 632 /**
 633  * eat all token until a ';' is reached or a stop token is found.
 634  */
 635 static void eat_statement(void)
 636 {
 637         eat_until_matching_token(';');
 638         if (token.type == ';')
 639                 next_token();
 640 }
 641
 642 #define eat(token_type)  do { assert(token.type == token_type); next_token(); } while (0)
 643
 644 /**
 645  * Report a parse error because an expected token was not found.
 646  */
 647 static
 648 #if defined __GNUC__ && __GNUC__ >= 4
 649 __attribute__((sentinel))
 650 #endif
 651 void parse_error_expected(const char *message, ...)
 652 {
 653         if (message != NULL) {
 654                 errorf(HERE, "%s", message);
 655         }
 656         va_list ap;
 657         va_start(ap, message);
 658         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 659         va_end(ap);
 660 }
 661
 662 /**
 663  * Report a type error.
 664  */
 665 static void type_error(const char *msg, const source_position_t *source_position,
 666                        type_t *type)
 667 {
 668         errorf(source_position, "%s, but found type '%T'", msg, type);
 669 }
 670
 671 /**
 672  * Report an incompatible type.
 673  */
 674 static void type_error_incompatible(const char *msg,
 675                 const source_position_t *source_position, type_t *type1, type_t *type2)
 676 {
 677         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 678                msg, type1, type2);
 679 }
 680
 681 /**
 682  * Expect the the current token is the expected token.
 683  * If not, generate an error, eat the current statement,
 684  * and goto the end_error label.
 685  */
 686 #define expect(expected)                              \
 687         do {                                              \
 688     if (UNLIKELY(token.type != (expected))) {          \
 689         parse_error_expected(NULL, (expected), NULL); \
 690                 add_anchor_token(expected);                   \
 691         eat_until_anchor();                           \
 692         if (token.type == expected)                   \
 693                 next_token();                             \
 694                 rem_anchor_token(expected);                   \
 695         goto end_error;                               \
 696     }                                                 \
 697     next_token();                                     \
 698         } while (0)
 699
 700 static void set_scope(scope_t *new_scope)
 701 {
 702         if (scope != NULL) {
 703                 scope->last_declaration = last_declaration;
 704         }
 705         scope = new_scope;
 706
 707         last_declaration = new_scope->last_declaration;
 708 }
 709
 710 /**
 711  * Search a symbol in a given namespace and returns its declaration or
 712  * NULL if this symbol was not found.
 713  */
 714 static declaration_t *get_declaration(const symbol_t *const symbol,
 715                                       const namespace_t namespc)
 716 {
 717         declaration_t *declaration = symbol->declaration;
 718         for( ; declaration != NULL; declaration = declaration->symbol_next) {
 719                 if (declaration->namespc == namespc)
 720                         return declaration;
 721         }
 722
 723         return NULL;
 724 }
 725
 726 /**
 727  * pushs an environment_entry on the environment stack and links the
 728  * corresponding symbol to the new entry
 729  */
 730 static void stack_push(stack_entry_t **stack_ptr, declaration_t *declaration)
 731 {
 732         symbol_t    *symbol  = declaration->symbol;
 733         namespace_t  namespc = (namespace_t) declaration->namespc;
 734
 735         /* replace/add declaration into declaration list of the symbol */
 736         declaration_t *iter = symbol->declaration;
 737         if (iter == NULL) {
 738                 symbol->declaration = declaration;
 739         } else {
 740                 declaration_t *iter_last = NULL;
 741                 for( ; iter != NULL; iter_last = iter, iter = iter->symbol_next) {
 742                         /* replace an entry? */
 743                         if (iter->namespc == namespc) {
 744                                 if (iter_last == NULL) {
 745                                         symbol->declaration = declaration;
 746                                 } else {
 747                                         iter_last->symbol_next = declaration;
 748                                 }
 749                                 declaration->symbol_next = iter->symbol_next;
 750                                 break;
 751                         }
 752                 }
 753                 if (iter == NULL) {
 754                         assert(iter_last->symbol_next == NULL);
 755                         iter_last->symbol_next = declaration;
 756                 }
 757         }
 758
 759         /* remember old declaration */
 760         stack_entry_t entry;
 761         entry.symbol          = symbol;
 762         entry.old_declaration = iter;
 763         entry.namespc         = (unsigned short) namespc;
 764         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 765 }
 766
 767 static void environment_push(declaration_t *declaration)
 768 {
 769         assert(declaration->source_position.input_name != NULL);
 770         assert(declaration->parent_scope != NULL);
 771         stack_push(&environment_stack, declaration);
 772 }
 773
 774 /**
 775  * Push a declaration of the label stack.
 776  *
 777  * @param declaration  the declaration
 778  */
 779 static void label_push(declaration_t *declaration)
 780 {
 781         declaration->parent_scope = &current_function->scope;
 782         stack_push(&label_stack, declaration);
 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                 declaration_t *old_declaration = entry->old_declaration;
 802                 symbol_t      *symbol          = entry->symbol;
 803                 namespace_t    namespc         = (namespace_t)entry->namespc;
 804
 805                 /* replace/remove declaration */
 806                 declaration_t *declaration = symbol->declaration;
 807                 assert(declaration != NULL);
 808                 if (declaration->namespc == namespc) {
 809                         if (old_declaration == NULL) {
 810                                 symbol->declaration = declaration->symbol_next;
 811                         } else {
 812                                 symbol->declaration = old_declaration;
 813                         }
 814                 } else {
 815                         declaration_t *iter_last = declaration;
 816                         declaration_t *iter      = declaration->symbol_next;
 817                         for( ; iter != NULL; iter_last = iter, iter = iter->symbol_next) {
 818                                 /* replace an entry? */
 819                                 if (iter->namespc == namespc) {
 820                                         assert(iter_last != NULL);
 821                                         iter_last->symbol_next = old_declaration;
 822                                         if (old_declaration != NULL) {
 823                                                 old_declaration->symbol_next = iter->symbol_next;
 824                                         }
 825                                         break;
 826                                 }
 827                         }
 828                         assert(iter != NULL);
 829                 }
 830         }
 831
 832         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
 833 }
 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 on the 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 static int get_rank(const type_t *type)
 857 {
 858         assert(!is_typeref(type));
 859         /* The C-standard allows promoting enums to int or unsigned int (see § 7.2.2
 860          * and esp. footnote 108). However we can't fold constants (yet), so we
 861          * can't decide whether unsigned int is possible, while int always works.
 862          * (unsigned int would be preferable when possible... for stuff like
 863          *  struct { enum { ... } bla : 4; } ) */
 864         if (type->kind == TYPE_ENUM)
 865                 return get_akind_rank(ATOMIC_TYPE_INT);
 866
 867         assert(type->kind == TYPE_ATOMIC);
 868         return get_akind_rank(type->atomic.akind);
 869 }
 870
 871 static type_t *promote_integer(type_t *type)
 872 {
 873         if (type->kind == TYPE_BITFIELD)
 874                 type = type->bitfield.base_type;
 875
 876         if (get_rank(type) < get_akind_rank(ATOMIC_TYPE_INT))
 877                 type = type_int;
 878
 879         return type;
 880 }
 881
 882 /**
 883  * Create a cast expression.
 884  *
 885  * @param expression  the expression to cast
 886  * @param dest_type   the destination type
 887  */
 888 static expression_t *create_cast_expression(expression_t *expression,
 889                                             type_t *dest_type)
 890 {
 891         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
 892
 893         cast->unary.value = expression;
 894         cast->base.type   = dest_type;
 895
 896         return cast;
 897 }
 898
 899 /**
 900  * Check if a given expression represents the 0 pointer constant.
 901  */
 902 static bool is_null_pointer_constant(const expression_t *expression)
 903 {
 904         /* skip void* cast */
 905         if (expression->kind == EXPR_UNARY_CAST
 906                         || expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
 907                 expression = expression->unary.value;
 908         }
 909
 910         /* TODO: not correct yet, should be any constant integer expression
 911          * which evaluates to 0 */
 912         if (expression->kind != EXPR_CONST)
 913                 return false;
 914
 915         type_t *const type = skip_typeref(expression->base.type);
 916         if (!is_type_integer(type))
 917                 return false;
 918
 919         return expression->conste.v.int_value == 0;
 920 }
 921
 922 /**
 923  * Create an implicit cast expression.
 924  *
 925  * @param expression  the expression to cast
 926  * @param dest_type   the destination type
 927  */
 928 static expression_t *create_implicit_cast(expression_t *expression,
 929                                           type_t *dest_type)
 930 {
 931         type_t *const source_type = expression->base.type;
 932
 933         if (source_type == dest_type)
 934                 return expression;
 935
 936         return create_cast_expression(expression, dest_type);
 937 }
 938
 939 typedef enum assign_error_t {
 940         ASSIGN_SUCCESS,
 941         ASSIGN_ERROR_INCOMPATIBLE,
 942         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
 943         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
 944         ASSIGN_WARNING_POINTER_FROM_INT,
 945         ASSIGN_WARNING_INT_FROM_POINTER
 946 } assign_error_t;
 947
 948 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
 949                                 const expression_t *const right,
 950                                 const char *context,
 951                                 const source_position_t *source_position)
 952 {
 953         type_t *const orig_type_right = right->base.type;
 954         type_t *const type_left       = skip_typeref(orig_type_left);
 955         type_t *const type_right      = skip_typeref(orig_type_right);
 956
 957         switch (error) {
 958         case ASSIGN_SUCCESS:
 959                 return;
 960         case ASSIGN_ERROR_INCOMPATIBLE:
 961                 errorf(source_position,
 962                        "destination type '%T' in %s is incompatible with type '%T'",
 963                        orig_type_left, context, orig_type_right);
 964                 return;
 965
 966         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
 967                 type_t *points_to_left
 968                         = skip_typeref(type_left->pointer.points_to);
 969                 type_t *points_to_right
 970                         = skip_typeref(type_right->pointer.points_to);
 971
 972                 /* the left type has all qualifiers from the right type */
 973                 unsigned missing_qualifiers
 974                         = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
 975                 warningf(source_position,
 976                          "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
 977                          orig_type_left, context, orig_type_right, missing_qualifiers);
 978                 return;
 979         }
 980
 981         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
 982                 warningf(source_position,
 983                          "destination type '%T' in %s is incompatible with '%E' of type '%T'",
 984                                  orig_type_left, context, right, orig_type_right);
 985                 return;
 986
 987         case ASSIGN_WARNING_POINTER_FROM_INT:
 988                 warningf(source_position,
 989                          "%s makes integer '%T' from pointer '%T' without a cast",
 990                                  context, orig_type_left, orig_type_right);
 991                 return;
 992
 993         case ASSIGN_WARNING_INT_FROM_POINTER:
 994                 warningf(source_position,
 995                                 "%s makes integer '%T' from pointer '%T' without a cast",
 996                                 context, orig_type_left, orig_type_right);
 997                 return;
 998
 999         default:
1000                 panic("invalid error value");
1001         }
1002 }
1003
1004 /** Implements the rules from § 6.5.16.1 */
1005 static assign_error_t semantic_assign(type_t *orig_type_left,
1006                                       const expression_t *const right)
1007 {
1008         type_t *const orig_type_right = right->base.type;
1009         type_t *const type_left       = skip_typeref(orig_type_left);
1010         type_t *const type_right      = skip_typeref(orig_type_right);
1011
1012         if (is_type_pointer(type_left)) {
1013                 if (is_null_pointer_constant(right)) {
1014                         return ASSIGN_SUCCESS;
1015                 } else if (is_type_pointer(type_right)) {
1016                         type_t *points_to_left
1017                                 = skip_typeref(type_left->pointer.points_to);
1018                         type_t *points_to_right
1019                                 = skip_typeref(type_right->pointer.points_to);
1020                         assign_error_t res = ASSIGN_SUCCESS;
1021
1022                         /* the left type has all qualifiers from the right type */
1023                         unsigned missing_qualifiers
1024                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1025                         if (missing_qualifiers != 0) {
1026                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1027                         }
1028
1029                         points_to_left  = get_unqualified_type(points_to_left);
1030                         points_to_right = get_unqualified_type(points_to_right);
1031
1032                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID) ||
1033                                         is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1034                                 return res;
1035                         }
1036
1037                         if (!types_compatible(points_to_left, points_to_right)) {
1038                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1039                         }
1040
1041                         return res;
1042                 } else if (is_type_integer(type_right)) {
1043                         return ASSIGN_WARNING_POINTER_FROM_INT;
1044                 }
1045         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1046             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1047                 && is_type_pointer(type_right))) {
1048                 return ASSIGN_SUCCESS;
1049         } else if ((is_type_compound(type_left)  && is_type_compound(type_right))
1050                         || (is_type_builtin(type_left) && is_type_builtin(type_right))) {
1051                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1052                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1053                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1054                         return ASSIGN_SUCCESS;
1055                 }
1056         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1057                 return ASSIGN_WARNING_INT_FROM_POINTER;
1058         }
1059
1060         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1061                 return ASSIGN_SUCCESS;
1062
1063         return ASSIGN_ERROR_INCOMPATIBLE;
1064 }
1065
1066 static expression_t *parse_constant_expression(void)
1067 {
1068         /* start parsing at precedence 7 (conditional expression) */
1069         expression_t *result = parse_sub_expression(7);
1070
1071         if (!is_constant_expression(result)) {
1072                 errorf(&result->base.source_position,
1073                        "expression '%E' is not constant\n", result);
1074         }
1075
1076         return result;
1077 }
1078
1079 static expression_t *parse_assignment_expression(void)
1080 {
1081         /* start parsing at precedence 2 (assignment expression) */
1082         return parse_sub_expression(2);
1083 }
1084
1085 static type_t *make_global_typedef(const char *name, type_t *type)
1086 {
1087         symbol_t *const symbol       = symbol_table_insert(name);
1088
1089         declaration_t *const declaration = allocate_declaration_zero();
1090         declaration->namespc                = NAMESPACE_NORMAL;
1091         declaration->storage_class          = STORAGE_CLASS_TYPEDEF;
1092         declaration->declared_storage_class = STORAGE_CLASS_TYPEDEF;
1093         declaration->type                   = type;
1094         declaration->symbol                 = symbol;
1095         declaration->source_position        = builtin_source_position;
1096         declaration->implicit               = true;
1097
1098         record_declaration(declaration, false);
1099
1100         type_t *typedef_type               = allocate_type_zero(TYPE_TYPEDEF, &builtin_source_position);
1101         typedef_type->typedeft.declaration = declaration;
1102
1103         return typedef_type;
1104 }
1105
1106 static string_t parse_string_literals(void)
1107 {
1108         assert(token.type == T_STRING_LITERAL);
1109         string_t result = token.v.string;
1110
1111         next_token();
1112
1113         while (token.type == T_STRING_LITERAL) {
1114                 result = concat_strings(&result, &token.v.string);
1115                 next_token();
1116         }
1117
1118         return result;
1119 }
1120
1121 static const char *const gnu_attribute_names[GNU_AK_LAST] = {
1122         [GNU_AK_CONST]                  = "const",
1123         [GNU_AK_VOLATILE]               = "volatile",
1124         [GNU_AK_CDECL]                  = "cdecl",
1125         [GNU_AK_STDCALL]                = "stdcall",
1126         [GNU_AK_FASTCALL]               = "fastcall",
1127         [GNU_AK_DEPRECATED]             = "deprecated",
1128         [GNU_AK_NOINLINE]               = "noinline",
1129         [GNU_AK_NORETURN]               = "noreturn",
1130         [GNU_AK_NAKED]                  = "naked",
1131         [GNU_AK_PURE]                   = "pure",
1132         [GNU_AK_ALWAYS_INLINE]          = "always_inline",
1133         [GNU_AK_MALLOC]                 = "malloc",
1134         [GNU_AK_WEAK]                   = "weak",
1135         [GNU_AK_CONSTRUCTOR]            = "constructor",
1136         [GNU_AK_DESTRUCTOR]             = "destructor",
1137         [GNU_AK_NOTHROW]                = "nothrow",
1138         [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
1139         [GNU_AK_COMMON]                 = "common",
1140         [GNU_AK_NOCOMMON]               = "nocommon",
1141         [GNU_AK_PACKED]                 = "packed",
1142         [GNU_AK_SHARED]                 = "shared",
1143         [GNU_AK_NOTSHARED]              = "notshared",
1144         [GNU_AK_USED]                   = "used",
1145         [GNU_AK_UNUSED]                 = "unused",
1146         [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
1147         [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
1148         [GNU_AK_LONGCALL]               = "longcall",
1149         [GNU_AK_SHORTCALL]              = "shortcall",
1150         [GNU_AK_LONG_CALL]              = "long_call",
1151         [GNU_AK_SHORT_CALL]             = "short_call",
1152         [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
1153         [GNU_AK_INTERRUPT]              = "interrupt",
1154         [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
1155         [GNU_AK_NMI_HANDLER]            = "nmi_handler",
1156         [GNU_AK_NESTING]                = "nesting",
1157         [GNU_AK_NEAR]                   = "near",
1158         [GNU_AK_FAR]                    = "far",
1159         [GNU_AK_SIGNAL]                 = "signal",
1160         [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
1161         [GNU_AK_TINY_DATA]              = "tiny_data",
1162         [GNU_AK_SAVEALL]                = "saveall",
1163         [GNU_AK_FLATTEN]                = "flatten",
1164         [GNU_AK_SSEREGPARM]             = "sseregparm",
1165         [GNU_AK_EXTERNALLY_VISIBLE]     = "externally_visible",
1166         [GNU_AK_RETURN_TWICE]           = "return_twice",
1167         [GNU_AK_MAY_ALIAS]              = "may_alias",
1168         [GNU_AK_MS_STRUCT]              = "ms_struct",
1169         [GNU_AK_GCC_STRUCT]             = "gcc_struct",
1170         [GNU_AK_DLLIMPORT]              = "dllimport",
1171         [GNU_AK_DLLEXPORT]              = "dllexport",
1172         [GNU_AK_ALIGNED]                = "aligned",
1173         [GNU_AK_ALIAS]                  = "alias",
1174         [GNU_AK_SECTION]                = "section",
1175         [GNU_AK_FORMAT]                 = "format",
1176         [GNU_AK_FORMAT_ARG]             = "format_arg",
1177         [GNU_AK_WEAKREF]                = "weakref",
1178         [GNU_AK_NONNULL]                = "nonnull",
1179         [GNU_AK_TLS_MODEL]              = "tls_model",
1180         [GNU_AK_VISIBILITY]             = "visibility",
1181         [GNU_AK_REGPARM]                = "regparm",
1182         [GNU_AK_MODE]                   = "mode",
1183         [GNU_AK_MODEL]                  = "model",
1184         [GNU_AK_TRAP_EXIT]              = "trap_exit",
1185         [GNU_AK_SP_SWITCH]              = "sp_switch",
1186         [GNU_AK_SENTINEL]               = "sentinel"
1187 };
1188
1189 /**
1190  * compare two string, ignoring double underscores on the second.
1191  */
1192 static int strcmp_underscore(const char *s1, const char *s2)
1193 {
1194         if (s2[0] == '_' && s2[1] == '_') {
1195                 size_t len2 = strlen(s2);
1196                 size_t len1 = strlen(s1);
1197                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1198                         return strncmp(s1, s2+2, len2-4);
1199                 }
1200         }
1201
1202         return strcmp(s1, s2);
1203 }
1204
1205 /**
1206  * Allocate a new gnu temporal attribute.
1207  */
1208 static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
1209 {
1210         gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
1211         attribute->kind            = kind;
1212         attribute->next            = NULL;
1213         attribute->invalid         = false;
1214         attribute->have_arguments  = false;
1215
1216         return attribute;
1217 }
1218
1219 /**
1220  * parse one constant expression argument.
1221  */
1222 static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
1223 {
1224         expression_t *expression;
1225         add_anchor_token(')');
1226         expression = parse_constant_expression();
1227         rem_anchor_token(')');
1228         expect(')');
1229         attribute->u.argument = fold_constant(expression);
1230         return;
1231 end_error:
1232         attribute->invalid = true;
1233 }
1234
1235 /**
1236  * parse a list of constant expressions arguments.
1237  */
1238 static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
1239 {
1240         argument_list_t **list = &attribute->u.arguments;
1241         argument_list_t  *entry;
1242         expression_t     *expression;
1243         add_anchor_token(')');
1244         add_anchor_token(',');
1245         while (true) {
1246                 expression = parse_constant_expression();
1247                 entry = obstack_alloc(&temp_obst, sizeof(entry));
1248                 entry->argument = fold_constant(expression);
1249                 entry->next     = NULL;
1250                 *list = entry;
1251                 list = &entry->next;
1252                 if (token.type != ',')
1253                         break;
1254                 next_token();
1255         }
1256         rem_anchor_token(',');
1257         rem_anchor_token(')');
1258         expect(')');
1259         return;
1260 end_error:
1261         attribute->invalid = true;
1262 }
1263
1264 /**
1265  * parse one string literal argument.
1266  */
1267 static void parse_gnu_attribute_string_arg(gnu_attribute_t *attribute,
1268                                            string_t *string)
1269 {
1270         add_anchor_token('(');
1271         if (token.type != T_STRING_LITERAL) {
1272                 parse_error_expected("while parsing attribute directive",
1273                                      T_STRING_LITERAL, NULL);
1274                 goto end_error;
1275         }
1276         *string = parse_string_literals();
1277         rem_anchor_token('(');
1278         expect(')');
1279         return;
1280 end_error:
1281         attribute->invalid = true;
1282 }
1283
1284 /**
1285  * parse one tls model.
1286  */
1287 static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
1288 {
1289         static const char *const tls_models[] = {
1290                 "global-dynamic",
1291                 "local-dynamic",
1292                 "initial-exec",
1293                 "local-exec"
1294         };
1295         string_t string = { NULL, 0 };
1296         parse_gnu_attribute_string_arg(attribute, &string);
1297         if (string.begin != NULL) {
1298                 for(size_t i = 0; i < 4; ++i) {
1299                         if (strcmp(tls_models[i], string.begin) == 0) {
1300                                 attribute->u.value = i;
1301                                 return;
1302                         }
1303                 }
1304                 errorf(HERE, "'%s' is an unrecognized tls model", string.begin);
1305         }
1306         attribute->invalid = true;
1307 }
1308
1309 /**
1310  * parse one tls model.
1311  */
1312 static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
1313 {
1314         static const char *const visibilities[] = {
1315                 "default",
1316                 "protected",
1317                 "hidden",
1318                 "internal"
1319         };
1320         string_t string = { NULL, 0 };
1321         parse_gnu_attribute_string_arg(attribute, &string);
1322         if (string.begin != NULL) {
1323                 for(size_t i = 0; i < 4; ++i) {
1324                         if (strcmp(visibilities[i], string.begin) == 0) {
1325                                 attribute->u.value = i;
1326                                 return;
1327                         }
1328                 }
1329                 errorf(HERE, "'%s' is an unrecognized visibility", string.begin);
1330         }
1331         attribute->invalid = true;
1332 }
1333
1334 /**
1335  * parse one (code) model.
1336  */
1337 static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
1338 {
1339         static const char *const visibilities[] = {
1340                 "small",
1341                 "medium",
1342                 "large"
1343         };
1344         string_t string = { NULL, 0 };
1345         parse_gnu_attribute_string_arg(attribute, &string);
1346         if (string.begin != NULL) {
1347                 for(int i = 0; i < 3; ++i) {
1348                         if (strcmp(visibilities[i], string.begin) == 0) {
1349                                 attribute->u.value = i;
1350                                 return;
1351                         }
1352                 }
1353                 errorf(HERE, "'%s' is an unrecognized model", string.begin);
1354         }
1355         attribute->invalid = true;
1356 }
1357
1358 static void parse_gnu_attribute_mode_arg(gnu_attribute_t *attribute)
1359 {
1360         /* TODO: find out what is allowed here... */
1361
1362         /* at least: byte, word, pointer, list of machine modes
1363          * __XXX___ is interpreted as XXX */
1364         add_anchor_token(')');
1365
1366         if (token.type != T_IDENTIFIER) {
1367                 expect(T_IDENTIFIER);
1368         }
1369
1370         /* This isn't really correct, the backend should provide a list of machine
1371          * specific modes (according to gcc philosophy that is...) */
1372         const char *symbol_str = token.v.symbol->string;
1373         if (strcmp_underscore("QI",   symbol_str) == 0 ||
1374             strcmp_underscore("byte", symbol_str) == 0) {
1375                 attribute->u.akind = ATOMIC_TYPE_CHAR;
1376         } else if (strcmp_underscore("HI", symbol_str) == 0) {
1377                 attribute->u.akind = ATOMIC_TYPE_SHORT;
1378         } else if (strcmp_underscore("SI",      symbol_str) == 0
1379                 || strcmp_underscore("word",    symbol_str) == 0
1380                 || strcmp_underscore("pointer", symbol_str) == 0) {
1381                 attribute->u.akind = ATOMIC_TYPE_INT;
1382         } else if (strcmp_underscore("DI", symbol_str) == 0) {
1383                 attribute->u.akind = ATOMIC_TYPE_LONGLONG;
1384         } else {
1385                 warningf(HERE, "ignoring unknown mode '%s'", symbol_str);
1386                 attribute->invalid = true;
1387         }
1388         next_token();
1389
1390         rem_anchor_token(')');
1391         expect(')');
1392         return;
1393 end_error:
1394         attribute->invalid = true;
1395 }
1396
1397 /**
1398  * parse one interrupt argument.
1399  */
1400 static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
1401 {
1402         static const char *const interrupts[] = {
1403                 "IRQ",
1404                 "FIQ",
1405                 "SWI",
1406                 "ABORT",
1407                 "UNDEF"
1408         };
1409         string_t string = { NULL, 0 };
1410         parse_gnu_attribute_string_arg(attribute, &string);
1411         if (string.begin != NULL) {
1412                 for(size_t i = 0; i < 5; ++i) {
1413                         if (strcmp(interrupts[i], string.begin) == 0) {
1414                                 attribute->u.value = i;
1415                                 return;
1416                         }
1417                 }
1418                 errorf(HERE, "'%s' is not an interrupt", string.begin);
1419         }
1420         attribute->invalid = true;
1421 }
1422
1423 /**
1424  * parse ( identifier, const expression, const expression )
1425  */
1426 static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
1427 {
1428         static const char *const format_names[] = {
1429                 "printf",
1430                 "scanf",
1431                 "strftime",
1432                 "strfmon"
1433         };
1434         int i;
1435
1436         if (token.type != T_IDENTIFIER) {
1437                 parse_error_expected("while parsing format attribute directive", T_IDENTIFIER, NULL);
1438                 goto end_error;
1439         }
1440         const char *name = token.v.symbol->string;
1441         for(i = 0; i < 4; ++i) {
1442                 if (strcmp_underscore(format_names[i], name) == 0)
1443                         break;
1444         }
1445         if (i >= 4) {
1446                 if (warning.attribute)
1447                         warningf(HERE, "'%s' is an unrecognized format function type", name);
1448         }
1449         next_token();
1450
1451         expect(',');
1452         add_anchor_token(')');
1453         add_anchor_token(',');
1454         parse_constant_expression();
1455         rem_anchor_token(',');
1456         rem_anchor_token('(');
1457
1458         expect(',');
1459         add_anchor_token(')');
1460         parse_constant_expression();
1461         rem_anchor_token('(');
1462         expect(')');
1463         return;
1464 end_error:
1465         attribute->u.value = true;
1466 }
1467
1468 static void check_no_argument(gnu_attribute_t *attribute, const char *name)
1469 {
1470         if (!attribute->have_arguments)
1471                 return;
1472
1473         /* should have no arguments */
1474         errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1475         eat_until_matching_token('(');
1476         /* we have already consumed '(', so we stop before ')', eat it */
1477         eat(')');
1478         attribute->invalid = true;
1479 }
1480
1481 /**
1482  * Parse one GNU attribute.
1483  *
1484  * Note that attribute names can be specified WITH or WITHOUT
1485  * double underscores, ie const or __const__.
1486  *
1487  * The following attributes are parsed without arguments
1488  *  const
1489  *  volatile
1490  *  cdecl
1491  *  stdcall
1492  *  fastcall
1493  *  deprecated
1494  *  noinline
1495  *  noreturn
1496  *  naked
1497  *  pure
1498  *  always_inline
1499  *  malloc
1500  *  weak
1501  *  constructor
1502  *  destructor
1503  *  nothrow
1504  *  transparent_union
1505  *  common
1506  *  nocommon
1507  *  packed
1508  *  shared
1509  *  notshared
1510  *  used
1511  *  unused
1512  *  no_instrument_function
1513  *  warn_unused_result
1514  *  longcall
1515  *  shortcall
1516  *  long_call
1517  *  short_call
1518  *  function_vector
1519  *  interrupt_handler
1520  *  nmi_handler
1521  *  nesting
1522  *  near
1523  *  far
1524  *  signal
1525  *  eightbit_data
1526  *  tiny_data
1527  *  saveall
1528  *  flatten
1529  *  sseregparm
1530  *  externally_visible
1531  *  return_twice
1532  *  may_alias
1533  *  ms_struct
1534  *  gcc_struct
1535  *  dllimport
1536  *  dllexport
1537  *
1538  * The following attributes are parsed with arguments
1539  *  aligned( const expression )
1540  *  alias( string literal )
1541  *  section( string literal )
1542  *  format( identifier, const expression, const expression )
1543  *  format_arg( const expression )
1544  *  tls_model( string literal )
1545  *  visibility( string literal )
1546  *  regparm( const expression )
1547  *  model( string leteral )
1548  *  trap_exit( const expression )
1549  *  sp_switch( string literal )
1550  *
1551  * The following attributes might have arguments
1552  *  weak_ref( string literal )
1553  *  non_null( const expression // ',' )
1554  *  interrupt( string literal )
1555  *  sentinel( constant expression )
1556  */
1557 static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
1558 {
1559         gnu_attribute_t *head      = *attributes;
1560         gnu_attribute_t *last      = *attributes;
1561         decl_modifiers_t modifiers = 0;
1562         gnu_attribute_t *attribute;
1563
1564         eat(T___attribute__);
1565         expect('(');
1566         expect('(');
1567
1568         if (token.type != ')') {
1569                 /* find the end of the list */
1570                 if (last != NULL) {
1571                         while (last->next != NULL)
1572                                 last = last->next;
1573                 }
1574
1575                 /* non-empty attribute list */
1576                 while (true) {
1577                         const char *name;
1578                         if (token.type == T_const) {
1579                                 name = "const";
1580                         } else if (token.type == T_volatile) {
1581                                 name = "volatile";
1582                         } else if (token.type == T_cdecl) {
1583                                 /* __attribute__((cdecl)), WITH ms mode */
1584                                 name = "cdecl";
1585                         } else if (token.type == T_IDENTIFIER) {
1586                                 const symbol_t *sym = token.v.symbol;
1587                                 name = sym->string;
1588                         } else {
1589                                 parse_error_expected("while parsing GNU attribute", T_IDENTIFIER, NULL);
1590                                 break;
1591                         }
1592
1593                         next_token();
1594
1595                         int i;
1596                         for(i = 0; i < GNU_AK_LAST; ++i) {
1597                                 if (strcmp_underscore(gnu_attribute_names[i], name) == 0)
1598                                         break;
1599                         }
1600                         gnu_attribute_kind_t kind = (gnu_attribute_kind_t)i;
1601
1602                         attribute = NULL;
1603                         if (kind == GNU_AK_LAST) {
1604                                 if (warning.attribute)
1605                                         warningf(HERE, "'%s' attribute directive ignored", name);
1606
1607                                 /* skip possible arguments */
1608                                 if (token.type == '(') {
1609                                         eat_until_matching_token(')');
1610                                 }
1611                         } else {
1612                                 /* check for arguments */
1613                                 attribute = allocate_gnu_attribute(kind);
1614                                 if (token.type == '(') {
1615                                         next_token();
1616                                         if (token.type == ')') {
1617                                                 /* empty args are allowed */
1618                                                 next_token();
1619                                         } else
1620                                                 attribute->have_arguments = true;
1621                                 }
1622
1623                                 switch(kind) {
1624                                 case GNU_AK_CONST:
1625                                 case GNU_AK_VOLATILE:
1626                                 case GNU_AK_NAKED:
1627                                 case GNU_AK_MALLOC:
1628                                 case GNU_AK_WEAK:
1629                                 case GNU_AK_COMMON:
1630                                 case GNU_AK_NOCOMMON:
1631                                 case GNU_AK_SHARED:
1632                                 case GNU_AK_NOTSHARED:
1633                                 case GNU_AK_NO_INSTRUMENT_FUNCTION:
1634                                 case GNU_AK_WARN_UNUSED_RESULT:
1635                                 case GNU_AK_LONGCALL:
1636                                 case GNU_AK_SHORTCALL:
1637                                 case GNU_AK_LONG_CALL:
1638                                 case GNU_AK_SHORT_CALL:
1639                                 case GNU_AK_FUNCTION_VECTOR:
1640                                 case GNU_AK_INTERRUPT_HANDLER:
1641                                 case GNU_AK_NMI_HANDLER:
1642                                 case GNU_AK_NESTING:
1643                                 case GNU_AK_NEAR:
1644                                 case GNU_AK_FAR:
1645                                 case GNU_AK_SIGNAL:
1646                                 case GNU_AK_EIGTHBIT_DATA:
1647                                 case GNU_AK_TINY_DATA:
1648                                 case GNU_AK_SAVEALL:
1649                                 case GNU_AK_FLATTEN:
1650                                 case GNU_AK_SSEREGPARM:
1651                                 case GNU_AK_EXTERNALLY_VISIBLE:
1652                                 case GNU_AK_RETURN_TWICE:
1653                                 case GNU_AK_MAY_ALIAS:
1654                                 case GNU_AK_MS_STRUCT:
1655                                 case GNU_AK_GCC_STRUCT:
1656                                         goto no_arg;
1657
1658                                 case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
1659                                 case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
1660                                 case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
1661                                 case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
1662                                 case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
1663                                 case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
1664                                 case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
1665                                 case GNU_AK_DLLIMPORT:         modifiers |= DM_DLLIMPORT;         goto no_arg;
1666                                 case GNU_AK_DLLEXPORT:         modifiers |= DM_DLLEXPORT;         goto no_arg;
1667                                 case GNU_AK_PACKED:            modifiers |= DM_PACKED;            goto no_arg;
1668                                 case GNU_AK_NOINLINE:          modifiers |= DM_NOINLINE;          goto no_arg;
1669                                 case GNU_AK_NORETURN:          modifiers |= DM_NORETURN;          goto no_arg;
1670                                 case GNU_AK_NOTHROW:           modifiers |= DM_NOTHROW;           goto no_arg;
1671                                 case GNU_AK_TRANSPARENT_UNION: modifiers |= DM_TRANSPARENT_UNION; goto no_arg;
1672                                 case GNU_AK_CONSTRUCTOR:       modifiers |= DM_CONSTRUCTOR;       goto no_arg;
1673                                 case GNU_AK_DESTRUCTOR:        modifiers |= DM_DESTRUCTOR;        goto no_arg;
1674                                 case GNU_AK_DEPRECATED:        modifiers |= DM_DEPRECATED;        goto no_arg;
1675
1676                                 case GNU_AK_ALIGNED:
1677                                         /* __align__ may be used without an argument */
1678                                         if (attribute->have_arguments) {
1679                                                 parse_gnu_attribute_const_arg(attribute);
1680                                         }
1681                                         break;
1682
1683                                 case GNU_AK_FORMAT_ARG:
1684                                 case GNU_AK_REGPARM:
1685                                 case GNU_AK_TRAP_EXIT:
1686                                         if (!attribute->have_arguments) {
1687                                                 /* should have arguments */
1688                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1689                                                 attribute->invalid = true;
1690                                         } else
1691                                                 parse_gnu_attribute_const_arg(attribute);
1692                                         break;
1693                                 case GNU_AK_ALIAS:
1694                                 case GNU_AK_SECTION:
1695                                 case GNU_AK_SP_SWITCH:
1696                                         if (!attribute->have_arguments) {
1697                                                 /* should have arguments */
1698                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1699                                                 attribute->invalid = true;
1700                                         } else
1701                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1702                                         break;
1703                                 case GNU_AK_FORMAT:
1704                                         if (!attribute->have_arguments) {
1705                                                 /* should have arguments */
1706                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1707                                                 attribute->invalid = true;
1708                                         } else
1709                                                 parse_gnu_attribute_format_args(attribute);
1710                                         break;
1711                                 case GNU_AK_WEAKREF:
1712                                         /* may have one string argument */
1713                                         if (attribute->have_arguments)
1714                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1715                                         break;
1716                                 case GNU_AK_NONNULL:
1717                                         if (attribute->have_arguments)
1718                                                 parse_gnu_attribute_const_arg_list(attribute);
1719                                         break;
1720                                 case GNU_AK_TLS_MODEL:
1721                                         if (!attribute->have_arguments) {
1722                                                 /* should have arguments */
1723                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1724                                         } else
1725                                                 parse_gnu_attribute_tls_model_arg(attribute);
1726                                         break;
1727                                 case GNU_AK_VISIBILITY:
1728                                         if (!attribute->have_arguments) {
1729                                                 /* should have arguments */
1730                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1731                                         } else
1732                                                 parse_gnu_attribute_visibility_arg(attribute);
1733                                         break;
1734                                 case GNU_AK_MODEL:
1735                                         if (!attribute->have_arguments) {
1736                                                 /* should have arguments */
1737                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1738                                         } else {
1739                                                 parse_gnu_attribute_model_arg(attribute);
1740                                         }
1741                                         break;
1742                                 case GNU_AK_MODE:
1743                                         if (!attribute->have_arguments) {
1744                                                 /* should have arguments */
1745                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1746                                         } else {
1747                                                 parse_gnu_attribute_mode_arg(attribute);
1748                                         }
1749                                         break;
1750                                 case GNU_AK_INTERRUPT:
1751                                         /* may have one string argument */
1752                                         if (attribute->have_arguments)
1753                                                 parse_gnu_attribute_interrupt_arg(attribute);
1754                                         break;
1755                                 case GNU_AK_SENTINEL:
1756                                         /* may have one string argument */
1757                                         if (attribute->have_arguments)
1758                                                 parse_gnu_attribute_const_arg(attribute);
1759                                         break;
1760                                 case GNU_AK_LAST:
1761                                         /* already handled */
1762                                         break;
1763
1764 no_arg:
1765                                         check_no_argument(attribute, name);
1766                                 }
1767                         }
1768                         if (attribute != NULL) {
1769                                 if (last != NULL) {
1770                                         last->next = attribute;
1771                                         last       = attribute;
1772                                 } else {
1773                                         head = last = attribute;
1774                                 }
1775                         }
1776
1777                         if (token.type != ',')
1778                                 break;
1779                         next_token();
1780                 }
1781         }
1782         expect(')');
1783         expect(')');
1784 end_error:
1785         *attributes = head;
1786
1787         return modifiers;
1788 }
1789
1790 /**
1791  * Parse GNU attributes.
1792  */
1793 static decl_modifiers_t parse_attributes(gnu_attribute_t **attributes)
1794 {
1795         decl_modifiers_t modifiers = 0;
1796
1797         while (true) {
1798                 switch(token.type) {
1799                 case T___attribute__:
1800                         modifiers |= parse_gnu_attribute(attributes);
1801                         continue;
1802
1803                 case T_asm:
1804                         next_token();
1805                         expect('(');
1806                         if (token.type != T_STRING_LITERAL) {
1807                                 parse_error_expected("while parsing assembler attribute",
1808                                                      T_STRING_LITERAL, NULL);
1809                                 eat_until_matching_token('(');
1810                                 break;
1811                         } else {
1812                                 parse_string_literals();
1813                         }
1814                         expect(')');
1815                         continue;
1816
1817                 case T_cdecl:     modifiers |= DM_CDECL;    break;
1818                 case T__fastcall: modifiers |= DM_FASTCALL; break;
1819                 case T__stdcall:  modifiers |= DM_STDCALL;  break;
1820
1821                 case T___thiscall:
1822                         /* TODO record modifier */
1823                         warningf(HERE, "Ignoring declaration modifier %K", &token);
1824                         break;
1825
1826 end_error:
1827                 default: return modifiers;
1828                 }
1829
1830                 next_token();
1831         }
1832 }
1833
1834 static designator_t *parse_designation(void)
1835 {
1836         designator_t *result = NULL;
1837         designator_t *last   = NULL;
1838
1839         while (true) {
1840                 designator_t *designator;
1841                 switch(token.type) {
1842                 case '[':
1843                         designator = allocate_ast_zero(sizeof(designator[0]));
1844                         designator->source_position = token.source_position;
1845                         next_token();
1846                         add_anchor_token(']');
1847                         designator->array_index = parse_constant_expression();
1848                         rem_anchor_token(']');
1849                         expect(']');
1850                         break;
1851                 case '.':
1852                         designator = allocate_ast_zero(sizeof(designator[0]));
1853                         designator->source_position = token.source_position;
1854                         next_token();
1855                         if (token.type != T_IDENTIFIER) {
1856                                 parse_error_expected("while parsing designator",
1857                                                      T_IDENTIFIER, NULL);
1858                                 return NULL;
1859                         }
1860                         designator->symbol = token.v.symbol;
1861                         next_token();
1862                         break;
1863                 default:
1864                         expect('=');
1865                         return result;
1866                 }
1867
1868                 assert(designator != NULL);
1869                 if (last != NULL) {
1870                         last->next = designator;
1871                 } else {
1872                         result = designator;
1873                 }
1874                 last = designator;
1875         }
1876 end_error:
1877         return NULL;
1878 }
1879
1880 static initializer_t *initializer_from_string(array_type_t *type,
1881                                               const string_t *const string)
1882 {
1883         /* TODO: check len vs. size of array type */
1884         (void) type;
1885
1886         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
1887         initializer->string.string = *string;
1888
1889         return initializer;
1890 }
1891
1892 static initializer_t *initializer_from_wide_string(array_type_t *const type,
1893                                                    wide_string_t *const string)
1894 {
1895         /* TODO: check len vs. size of array type */
1896         (void) type;
1897
1898         initializer_t *const initializer =
1899                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
1900         initializer->wide_string.string = *string;
1901
1902         return initializer;
1903 }
1904
1905 /**
1906  * Build an initializer from a given expression.
1907  */
1908 static initializer_t *initializer_from_expression(type_t *orig_type,
1909                                                   expression_t *expression)
1910 {
1911         /* TODO check that expression is a constant expression */
1912
1913         /* § 6.7.8.14/15 char array may be initialized by string literals */
1914         type_t *type           = skip_typeref(orig_type);
1915         type_t *expr_type_orig = expression->base.type;
1916         type_t *expr_type      = skip_typeref(expr_type_orig);
1917         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
1918                 array_type_t *const array_type   = &type->array;
1919                 type_t       *const element_type = skip_typeref(array_type->element_type);
1920
1921                 if (element_type->kind == TYPE_ATOMIC) {
1922                         atomic_type_kind_t akind = element_type->atomic.akind;
1923                         switch (expression->kind) {
1924                                 case EXPR_STRING_LITERAL:
1925                                         if (akind == ATOMIC_TYPE_CHAR
1926                                                         || akind == ATOMIC_TYPE_SCHAR
1927                                                         || akind == ATOMIC_TYPE_UCHAR) {
1928                                                 return initializer_from_string(array_type,
1929                                                         &expression->string.value);
1930                                         }
1931
1932                                 case EXPR_WIDE_STRING_LITERAL: {
1933                                         type_t *bare_wchar_type = skip_typeref(type_wchar_t);
1934                                         if (get_unqualified_type(element_type) == bare_wchar_type) {
1935                                                 return initializer_from_wide_string(array_type,
1936                                                         &expression->wide_string.value);
1937                                         }
1938                                 }
1939
1940                                 default:
1941                                         break;
1942                         }
1943                 }
1944         }
1945
1946         assign_error_t error = semantic_assign(type, expression);
1947         if (error == ASSIGN_ERROR_INCOMPATIBLE)
1948                 return NULL;
1949         report_assign_error(error, type, expression, "initializer",
1950                             &expression->base.source_position);
1951
1952         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
1953         result->value.value = create_implicit_cast(expression, type);
1954
1955         return result;
1956 }
1957
1958 /**
1959  * Checks if a given expression can be used as an constant initializer.
1960  */
1961 static bool is_initializer_constant(const expression_t *expression)
1962 {
1963         return is_constant_expression(expression)
1964                 || is_address_constant(expression);
1965 }
1966
1967 /**
1968  * Parses an scalar initializer.
1969  *
1970  * § 6.7.8.11; eat {} without warning
1971  */
1972 static initializer_t *parse_scalar_initializer(type_t *type,
1973                                                bool must_be_constant)
1974 {
1975         /* there might be extra {} hierarchies */
1976         int braces = 0;
1977         if (token.type == '{') {
1978                 warningf(HERE, "extra curly braces around scalar initializer");
1979                 do {
1980                         ++braces;
1981                         next_token();
1982                 } while (token.type == '{');
1983         }
1984
1985         expression_t *expression = parse_assignment_expression();
1986         if (must_be_constant && !is_initializer_constant(expression)) {
1987                 errorf(&expression->base.source_position,
1988                        "Initialisation expression '%E' is not constant\n",
1989                        expression);
1990         }
1991
1992         initializer_t *initializer = initializer_from_expression(type, expression);
1993
1994         if (initializer == NULL) {
1995                 errorf(&expression->base.source_position,
1996                        "expression '%E' (type '%T') doesn't match expected type '%T'",
1997                        expression, expression->base.type, type);
1998                 /* TODO */
1999                 return NULL;
2000         }
2001
2002         bool additional_warning_displayed = false;
2003         while (braces > 0) {
2004                 if (token.type == ',') {
2005                         next_token();
2006                 }
2007                 if (token.type != '}') {
2008                         if (!additional_warning_displayed) {
2009                                 warningf(HERE, "additional elements in scalar initializer");
2010                                 additional_warning_displayed = true;
2011                         }
2012                 }
2013                 eat_block();
2014                 braces--;
2015         }
2016
2017         return initializer;
2018 }
2019
2020 /**
2021  * An entry in the type path.
2022  */
2023 typedef struct type_path_entry_t type_path_entry_t;
2024 struct type_path_entry_t {
2025         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
2026         union {
2027                 size_t         index;          /**< For array types: the current index. */
2028                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
2029         } v;
2030 };
2031
2032 /**
2033  * A type path expression a position inside compound or array types.
2034  */
2035 typedef struct type_path_t type_path_t;
2036 struct type_path_t {
2037         type_path_entry_t *path;         /**< An flexible array containing the current path. */
2038         type_t            *top_type;     /**< type of the element the path points */
2039         size_t             max_index;    /**< largest index in outermost array */
2040 };
2041
2042 /**
2043  * Prints a type path for debugging.
2044  */
2045 static __attribute__((unused)) void debug_print_type_path(
2046                 const type_path_t *path)
2047 {
2048         size_t len = ARR_LEN(path->path);
2049
2050         for(size_t i = 0; i < len; ++i) {
2051                 const type_path_entry_t *entry = & path->path[i];
2052
2053                 type_t *type = skip_typeref(entry->type);
2054                 if (is_type_compound(type)) {
2055                         /* in gcc mode structs can have no members */
2056                         if (entry->v.compound_entry == NULL) {
2057                                 assert(i == len-1);
2058                                 continue;
2059                         }
2060                         fprintf(stderr, ".%s", entry->v.compound_entry->symbol->string);
2061                 } else if (is_type_array(type)) {
2062                         fprintf(stderr, "[%zu]", entry->v.index);
2063                 } else {
2064                         fprintf(stderr, "-INVALID-");
2065                 }
2066         }
2067         if (path->top_type != NULL) {
2068                 fprintf(stderr, "  (");
2069                 print_type(path->top_type);
2070                 fprintf(stderr, ")");
2071         }
2072 }
2073
2074 /**
2075  * Return the top type path entry, ie. in a path
2076  * (type).a.b returns the b.
2077  */
2078 static type_path_entry_t *get_type_path_top(const type_path_t *path)
2079 {
2080         size_t len = ARR_LEN(path->path);
2081         assert(len > 0);
2082         return &path->path[len-1];
2083 }
2084
2085 /**
2086  * Enlarge the type path by an (empty) element.
2087  */
2088 static type_path_entry_t *append_to_type_path(type_path_t *path)
2089 {
2090         size_t len = ARR_LEN(path->path);
2091         ARR_RESIZE(type_path_entry_t, path->path, len+1);
2092
2093         type_path_entry_t *result = & path->path[len];
2094         memset(result, 0, sizeof(result[0]));
2095         return result;
2096 }
2097
2098 /**
2099  * Descending into a sub-type. Enter the scope of the current
2100  * top_type.
2101  */
2102 static void descend_into_subtype(type_path_t *path)
2103 {
2104         type_t *orig_top_type = path->top_type;
2105         type_t *top_type      = skip_typeref(orig_top_type);
2106
2107         assert(is_type_compound(top_type) || is_type_array(top_type));
2108
2109         type_path_entry_t *top = append_to_type_path(path);
2110         top->type              = top_type;
2111
2112         if (is_type_compound(top_type)) {
2113                 declaration_t *declaration = top_type->compound.declaration;
2114                 declaration_t *entry       = declaration->scope.declarations;
2115                 top->v.compound_entry      = entry;
2116
2117                 if (entry != NULL) {
2118                         path->top_type         = entry->type;
2119                 } else {
2120                         path->top_type         = NULL;
2121                 }
2122         } else {
2123                 assert(is_type_array(top_type));
2124
2125                 top->v.index   = 0;
2126                 path->top_type = top_type->array.element_type;
2127         }
2128 }
2129
2130 /**
2131  * Pop an entry from the given type path, ie. returning from
2132  * (type).a.b to (type).a
2133  */
2134 static void ascend_from_subtype(type_path_t *path)
2135 {
2136         type_path_entry_t *top = get_type_path_top(path);
2137
2138         path->top_type = top->type;
2139
2140         size_t len = ARR_LEN(path->path);
2141         ARR_RESIZE(type_path_entry_t, path->path, len-1);
2142 }
2143
2144 /**
2145  * Pop entries from the given type path until the given
2146  * path level is reached.
2147  */
2148 static void ascend_to(type_path_t *path, size_t top_path_level)
2149 {
2150         size_t len = ARR_LEN(path->path);
2151
2152         while (len > top_path_level) {
2153                 ascend_from_subtype(path);
2154                 len = ARR_LEN(path->path);
2155         }
2156 }
2157
2158 static bool walk_designator(type_path_t *path, const designator_t *designator,
2159                             bool used_in_offsetof)
2160 {
2161         for( ; designator != NULL; designator = designator->next) {
2162                 type_path_entry_t *top       = get_type_path_top(path);
2163                 type_t            *orig_type = top->type;
2164
2165                 type_t *type = skip_typeref(orig_type);
2166
2167                 if (designator->symbol != NULL) {
2168                         symbol_t *symbol = designator->symbol;
2169                         if (!is_type_compound(type)) {
2170                                 if (is_type_valid(type)) {
2171                                         errorf(&designator->source_position,
2172                                                "'.%Y' designator used for non-compound type '%T'",
2173                                                symbol, orig_type);
2174                                 }
2175                                 goto failed;
2176                         }
2177
2178                         declaration_t *declaration = type->compound.declaration;
2179                         declaration_t *iter        = declaration->scope.declarations;
2180                         for( ; iter != NULL; iter = iter->next) {
2181                                 if (iter->symbol == symbol) {
2182                                         break;
2183                                 }
2184                         }
2185                         if (iter == NULL) {
2186                                 errorf(&designator->source_position,
2187                                        "'%T' has no member named '%Y'", orig_type, symbol);
2188                                 goto failed;
2189                         }
2190                         if (used_in_offsetof) {
2191                                 type_t *real_type = skip_typeref(iter->type);
2192                                 if (real_type->kind == TYPE_BITFIELD) {
2193                                         errorf(&designator->source_position,
2194                                                "offsetof designator '%Y' may not specify bitfield",
2195                                                symbol);
2196                                         goto failed;
2197                                 }
2198                         }
2199
2200                         top->type             = orig_type;
2201                         top->v.compound_entry = iter;
2202                         orig_type             = iter->type;
2203                 } else {
2204                         expression_t *array_index = designator->array_index;
2205                         assert(designator->array_index != NULL);
2206
2207                         if (!is_type_array(type)) {
2208                                 if (is_type_valid(type)) {
2209                                         errorf(&designator->source_position,
2210                                                "[%E] designator used for non-array type '%T'",
2211                                                array_index, orig_type);
2212                                 }
2213                                 goto failed;
2214                         }
2215                         if (!is_type_valid(array_index->base.type)) {
2216                                 goto failed;
2217                         }
2218
2219                         long index = fold_constant(array_index);
2220                         if (!used_in_offsetof) {
2221                                 if (index < 0) {
2222                                         errorf(&designator->source_position,
2223                                                "array index [%E] must be positive", array_index);
2224                                         goto failed;
2225                                 }
2226                                 if (type->array.size_constant == true) {
2227                                         long array_size = type->array.size;
2228                                         if (index >= array_size) {
2229                                                 errorf(&designator->source_position,
2230                                                        "designator [%E] (%d) exceeds array size %d",
2231                                                        array_index, index, array_size);
2232                                                 goto failed;
2233                                         }
2234                                 }
2235                         }
2236
2237                         top->type    = orig_type;
2238                         top->v.index = (size_t) index;
2239                         orig_type    = type->array.element_type;
2240                 }
2241                 path->top_type = orig_type;
2242
2243                 if (designator->next != NULL) {
2244                         descend_into_subtype(path);
2245                 }
2246         }
2247         return true;
2248
2249 failed:
2250         return false;
2251 }
2252
2253 static void advance_current_object(type_path_t *path, size_t top_path_level)
2254 {
2255         type_path_entry_t *top = get_type_path_top(path);
2256
2257         type_t *type = skip_typeref(top->type);
2258         if (is_type_union(type)) {
2259                 /* in unions only the first element is initialized */
2260                 top->v.compound_entry = NULL;
2261         } else if (is_type_struct(type)) {
2262                 declaration_t *entry = top->v.compound_entry;
2263
2264                 entry                 = entry->next;
2265                 top->v.compound_entry = entry;
2266                 if (entry != NULL) {
2267                         path->top_type = entry->type;
2268                         return;
2269                 }
2270         } else {
2271                 assert(is_type_array(type));
2272
2273                 top->v.index++;
2274
2275                 if (!type->array.size_constant || top->v.index < type->array.size) {
2276                         return;
2277                 }
2278         }
2279
2280         /* we're past the last member of the current sub-aggregate, try if we
2281          * can ascend in the type hierarchy and continue with another subobject */
2282         size_t len = ARR_LEN(path->path);
2283
2284         if (len > top_path_level) {
2285                 ascend_from_subtype(path);
2286                 advance_current_object(path, top_path_level);
2287         } else {
2288                 path->top_type = NULL;
2289         }
2290 }
2291
2292 /**
2293  * skip until token is found.
2294  */
2295 static void skip_until(int type)
2296 {
2297         while (token.type != type) {
2298                 if (token.type == T_EOF)
2299                         return;
2300                 next_token();
2301         }
2302 }
2303
2304 /**
2305  * skip any {...} blocks until a closing bracket is reached.
2306  */
2307 static void skip_initializers(void)
2308 {
2309         if (token.type == '{')
2310                 next_token();
2311
2312         while (token.type != '}') {
2313                 if (token.type == T_EOF)
2314                         return;
2315                 if (token.type == '{') {
2316                         eat_block();
2317                         continue;
2318                 }
2319                 next_token();
2320         }
2321 }
2322
2323 static initializer_t *create_empty_initializer(void)
2324 {
2325         static initializer_t empty_initializer
2326                 = { .list = { { INITIALIZER_LIST }, 0 } };
2327         return &empty_initializer;
2328 }
2329
2330 /**
2331  * Parse a part of an initialiser for a struct or union,
2332  */
2333 static initializer_t *parse_sub_initializer(type_path_t *path,
2334                 type_t *outer_type, size_t top_path_level,
2335                 parse_initializer_env_t *env)
2336 {
2337         if (token.type == '}') {
2338                 /* empty initializer */
2339                 return create_empty_initializer();
2340         }
2341
2342         type_t *orig_type = path->top_type;
2343         type_t *type      = NULL;
2344
2345         if (orig_type == NULL) {
2346                 /* We are initializing an empty compound. */
2347         } else {
2348                 type = skip_typeref(orig_type);
2349
2350                 /* we can't do usefull stuff if we didn't even parse the type. Skip the
2351                  * initializers in this case. */
2352                 if (!is_type_valid(type)) {
2353                         skip_initializers();
2354                         return create_empty_initializer();
2355                 }
2356         }
2357
2358         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2359
2360         while (true) {
2361                 designator_t *designator = NULL;
2362                 if (token.type == '.' || token.type == '[') {
2363                         designator = parse_designation();
2364                         goto finish_designator;
2365                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2366                         /* GNU-style designator ("identifier: value") */
2367                         designator = allocate_ast_zero(sizeof(designator[0]));
2368                         designator->source_position = token.source_position;
2369                         designator->symbol          = token.v.symbol;
2370                         eat(T_IDENTIFIER);
2371                         eat(':');
2372
2373 finish_designator:
2374                         /* reset path to toplevel, evaluate designator from there */
2375                         ascend_to(path, top_path_level);
2376                         if (!walk_designator(path, designator, false)) {
2377                                 /* can't continue after designation error */
2378                                 goto end_error;
2379                         }
2380
2381                         initializer_t *designator_initializer
2382                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2383                         designator_initializer->designator.designator = designator;
2384                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2385
2386                         orig_type = path->top_type;
2387                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2388                 }
2389
2390                 initializer_t *sub;
2391
2392                 if (token.type == '{') {
2393                         if (type != NULL && is_type_scalar(type)) {
2394                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2395                         } else {
2396                                 eat('{');
2397                                 if (type == NULL) {
2398                                         if (env->declaration != NULL) {
2399                                                 errorf(HERE, "extra brace group at end of initializer for '%Y'",
2400                                                        env->declaration->symbol);
2401                                         } else {
2402                                                 errorf(HERE, "extra brace group at end of initializer");
2403                                         }
2404                                 } else
2405                                         descend_into_subtype(path);
2406
2407                                 add_anchor_token('}');
2408                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2409                                                             env);
2410                                 rem_anchor_token('}');
2411
2412                                 if (type != NULL) {
2413                                         ascend_from_subtype(path);
2414                                         expect('}');
2415                                 } else {
2416                                         expect('}');
2417                                         goto error_parse_next;
2418                                 }
2419                         }
2420                 } else {
2421                         /* must be an expression */
2422                         expression_t *expression = parse_assignment_expression();
2423
2424                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2425                                 errorf(&expression->base.source_position,
2426                                        "Initialisation expression '%E' is not constant\n",
2427                                        expression);
2428                         }
2429
2430                         if (type == NULL) {
2431                                 /* we are already outside, ... */
2432                                 goto error_excess;
2433                         }
2434
2435                         /* handle { "string" } special case */
2436                         if ((expression->kind == EXPR_STRING_LITERAL
2437                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2438                                         && outer_type != NULL) {
2439                                 sub = initializer_from_expression(outer_type, expression);
2440                                 if (sub != NULL) {
2441                                         if (token.type == ',') {
2442                                                 next_token();
2443                                         }
2444                                         if (token.type != '}') {
2445                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2446                                                                  orig_type);
2447                                         }
2448                                         /* TODO: eat , ... */
2449                                         return sub;
2450                                 }
2451                         }
2452
2453                         /* descend into subtypes until expression matches type */
2454                         while (true) {
2455                                 orig_type = path->top_type;
2456                                 type      = skip_typeref(orig_type);
2457
2458                                 sub = initializer_from_expression(orig_type, expression);
2459                                 if (sub != NULL) {
2460                                         break;
2461                                 }
2462                                 if (!is_type_valid(type)) {
2463                                         goto end_error;
2464                                 }
2465                                 if (is_type_scalar(type)) {
2466                                         errorf(&expression->base.source_position,
2467                                                         "expression '%E' doesn't match expected type '%T'",
2468                                                         expression, orig_type);
2469                                         goto end_error;
2470                                 }
2471
2472                                 descend_into_subtype(path);
2473                         }
2474                 }
2475
2476                 /* update largest index of top array */
2477                 const type_path_entry_t *first      = &path->path[0];
2478                 type_t                  *first_type = first->type;
2479                 first_type                          = skip_typeref(first_type);
2480                 if (is_type_array(first_type)) {
2481                         size_t index = first->v.index;
2482                         if (index > path->max_index)
2483                                 path->max_index = index;
2484                 }
2485
2486                 if (type != NULL) {
2487                         /* append to initializers list */
2488                         ARR_APP1(initializer_t*, initializers, sub);
2489                 } else {
2490 error_excess:
2491                         if (env->declaration != NULL)
2492                                 warningf(HERE, "excess elements in struct initializer for '%Y'",
2493                                  env->declaration->symbol);
2494                         else
2495                                 warningf(HERE, "excess elements in struct initializer");
2496                 }
2497
2498 error_parse_next:
2499                 if (token.type == '}') {
2500                         break;
2501                 }
2502                 expect(',');
2503                 if (token.type == '}') {
2504                         break;
2505                 }
2506
2507                 if (type != NULL) {
2508                         /* advance to the next declaration if we are not at the end */
2509                         advance_current_object(path, top_path_level);
2510                         orig_type = path->top_type;
2511                         if (orig_type != NULL)
2512                                 type = skip_typeref(orig_type);
2513                         else
2514                                 type = NULL;
2515                 }
2516         }
2517
2518         size_t len  = ARR_LEN(initializers);
2519         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2520         initializer_t *result = allocate_ast_zero(size);
2521         result->kind          = INITIALIZER_LIST;
2522         result->list.len      = len;
2523         memcpy(&result->list.initializers, initializers,
2524                len * sizeof(initializers[0]));
2525
2526         DEL_ARR_F(initializers);
2527         ascend_to(path, top_path_level+1);
2528
2529         return result;
2530
2531 end_error:
2532         skip_initializers();
2533         DEL_ARR_F(initializers);
2534         ascend_to(path, top_path_level+1);
2535         return NULL;
2536 }
2537
2538 /**
2539  * Parses an initializer. Parsers either a compound literal
2540  * (env->declaration == NULL) or an initializer of a declaration.
2541  */
2542 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2543 {
2544         type_t        *type   = skip_typeref(env->type);
2545         initializer_t *result = NULL;
2546         size_t         max_index;
2547
2548         if (is_type_scalar(type)) {
2549                 result = parse_scalar_initializer(type, env->must_be_constant);
2550         } else if (token.type == '{') {
2551                 eat('{');
2552
2553                 type_path_t path;
2554                 memset(&path, 0, sizeof(path));
2555                 path.top_type = env->type;
2556                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2557
2558                 descend_into_subtype(&path);
2559
2560                 add_anchor_token('}');
2561                 result = parse_sub_initializer(&path, env->type, 1, env);
2562                 rem_anchor_token('}');
2563
2564                 max_index = path.max_index;
2565                 DEL_ARR_F(path.path);
2566
2567                 expect('}');
2568         } else {
2569                 /* parse_scalar_initializer() also works in this case: we simply
2570                  * have an expression without {} around it */
2571                 result = parse_scalar_initializer(type, env->must_be_constant);
2572         }
2573
2574         /* § 6.7.5 (22)  array initializers for arrays with unknown size determine
2575          * the array type size */
2576         if (is_type_array(type) && type->array.size_expression == NULL
2577                         && result != NULL) {
2578                 size_t size;
2579                 switch (result->kind) {
2580                 case INITIALIZER_LIST:
2581                         size = max_index + 1;
2582                         break;
2583
2584                 case INITIALIZER_STRING:
2585                         size = result->string.string.size;
2586                         break;
2587
2588                 case INITIALIZER_WIDE_STRING:
2589                         size = result->wide_string.string.size;
2590                         break;
2591
2592                 case INITIALIZER_DESIGNATOR:
2593                 case INITIALIZER_VALUE:
2594                         /* can happen for parse errors */
2595                         size = 0;
2596                         break;
2597
2598                 default:
2599                         internal_errorf(HERE, "invalid initializer type");
2600                 }
2601
2602                 expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2603                 cnst->base.type          = type_size_t;
2604                 cnst->conste.v.int_value = size;
2605
2606                 type_t *new_type = duplicate_type(type);
2607
2608                 new_type->array.size_expression = cnst;
2609                 new_type->array.size_constant   = true;
2610                 new_type->array.size            = size;
2611                 env->type = new_type;
2612         }
2613
2614         return result;
2615 end_error:
2616         return NULL;
2617 }
2618
2619 static declaration_t *append_declaration(declaration_t *declaration);
2620
2621 static declaration_t *parse_compound_type_specifier(bool is_struct)
2622 {
2623         gnu_attribute_t  *attributes = NULL;
2624         decl_modifiers_t  modifiers  = 0;
2625         if (is_struct) {
2626                 eat(T_struct);
2627         } else {
2628                 eat(T_union);
2629         }
2630
2631         symbol_t      *symbol      = NULL;
2632         declaration_t *declaration = NULL;
2633
2634         if (token.type == T___attribute__) {
2635                 modifiers |= parse_attributes(&attributes);
2636         }
2637
2638         if (token.type == T_IDENTIFIER) {
2639                 symbol = token.v.symbol;
2640                 next_token();
2641
2642                 namespace_t const namespc =
2643                         is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION;
2644                 declaration = get_declaration(symbol, namespc);
2645                 if (declaration != NULL) {
2646                         if (declaration->parent_scope != scope &&
2647                             (token.type == '{' || token.type == ';')) {
2648                                 declaration = NULL;
2649                         } else if (declaration->init.complete &&
2650                                    token.type == '{') {
2651                                 assert(symbol != NULL);
2652                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition at %P)",
2653                                        is_struct ? "struct" : "union", symbol,
2654                                        &declaration->source_position);
2655                                 declaration->scope.declarations = NULL;
2656                         }
2657                 }
2658         } else if (token.type != '{') {
2659                 if (is_struct) {
2660                         parse_error_expected("while parsing struct type specifier",
2661                                              T_IDENTIFIER, '{', NULL);
2662                 } else {
2663                         parse_error_expected("while parsing union type specifier",
2664                                              T_IDENTIFIER, '{', NULL);
2665                 }
2666
2667                 return NULL;
2668         }
2669
2670         if (declaration == NULL) {
2671                 declaration = allocate_declaration_zero();
2672                 declaration->namespc         =
2673                         (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
2674                 declaration->source_position = token.source_position;
2675                 declaration->symbol          = symbol;
2676                 declaration->parent_scope    = scope;
2677                 if (symbol != NULL) {
2678                         environment_push(declaration);
2679                 }
2680                 append_declaration(declaration);
2681         }
2682
2683         if (token.type == '{') {
2684                 declaration->init.complete = true;
2685
2686                 parse_compound_type_entries(declaration);
2687                 modifiers |= parse_attributes(&attributes);
2688         }
2689
2690         declaration->modifiers |= modifiers;
2691         return declaration;
2692 }
2693
2694 static void parse_enum_entries(type_t *const enum_type)
2695 {
2696         eat('{');
2697
2698         if (token.type == '}') {
2699                 next_token();
2700                 errorf(HERE, "empty enum not allowed");
2701                 return;
2702         }
2703
2704         add_anchor_token('}');
2705         do {
2706                 if (token.type != T_IDENTIFIER) {
2707                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
2708                         eat_block();
2709                         rem_anchor_token('}');
2710                         return;
2711                 }
2712
2713                 declaration_t *const entry = allocate_declaration_zero();
2714                 entry->storage_class   = STORAGE_CLASS_ENUM_ENTRY;
2715                 entry->type            = enum_type;
2716                 entry->symbol          = token.v.symbol;
2717                 entry->source_position = token.source_position;
2718                 next_token();
2719
2720                 if (token.type == '=') {
2721                         next_token();
2722                         expression_t *value = parse_constant_expression();
2723
2724                         value = create_implicit_cast(value, enum_type);
2725                         entry->init.enum_value = value;
2726
2727                         /* TODO semantic */
2728                 }
2729
2730                 record_declaration(entry, false);
2731
2732                 if (token.type != ',')
2733                         break;
2734                 next_token();
2735         } while (token.type != '}');
2736         rem_anchor_token('}');
2737
2738         expect('}');
2739
2740 end_error:
2741         ;
2742 }
2743
2744 static type_t *parse_enum_specifier(void)
2745 {
2746         gnu_attribute_t *attributes = NULL;
2747         declaration_t   *declaration;
2748         symbol_t        *symbol;
2749
2750         eat(T_enum);
2751         if (token.type == T_IDENTIFIER) {
2752                 symbol = token.v.symbol;
2753                 next_token();
2754
2755                 declaration = get_declaration(symbol, NAMESPACE_ENUM);
2756         } else if (token.type != '{') {
2757                 parse_error_expected("while parsing enum type specifier",
2758                                      T_IDENTIFIER, '{', NULL);
2759                 return NULL;
2760         } else {
2761                 declaration = NULL;
2762                 symbol      = NULL;
2763         }
2764
2765         if (declaration == NULL) {
2766                 declaration = allocate_declaration_zero();
2767                 declaration->namespc         = NAMESPACE_ENUM;
2768                 declaration->source_position = token.source_position;
2769                 declaration->symbol          = symbol;
2770                 declaration->parent_scope  = scope;
2771         }
2772
2773         type_t *const type      = allocate_type_zero(TYPE_ENUM, &declaration->source_position);
2774         type->enumt.declaration = declaration;
2775
2776         if (token.type == '{') {
2777                 if (declaration->init.complete) {
2778                         errorf(HERE, "multiple definitions of enum %Y", symbol);
2779                 }
2780                 if (symbol != NULL) {
2781                         environment_push(declaration);
2782                 }
2783                 append_declaration(declaration);
2784                 declaration->init.complete = true;
2785
2786                 parse_enum_entries(type);
2787                 parse_attributes(&attributes);
2788         }
2789
2790         return type;
2791 }
2792
2793 /**
2794  * if a symbol is a typedef to another type, return true
2795  */
2796 static bool is_typedef_symbol(symbol_t *symbol)
2797 {
2798         const declaration_t *const declaration =
2799                 get_declaration(symbol, NAMESPACE_NORMAL);
2800         return
2801                 declaration != NULL &&
2802                 declaration->storage_class == STORAGE_CLASS_TYPEDEF;
2803 }
2804
2805 static type_t *parse_typeof(void)
2806 {
2807         eat(T___typeof__);
2808
2809         type_t *type;
2810
2811         expect('(');
2812         add_anchor_token(')');
2813
2814         expression_t *expression  = NULL;
2815
2816 restart:
2817         switch(token.type) {
2818         case T___extension__:
2819                 /* This can be a prefix to a typename or an expression.  We simply eat
2820                  * it now. */
2821                 do {
2822                         next_token();
2823                 } while (token.type == T___extension__);
2824                 goto restart;
2825
2826         case T_IDENTIFIER:
2827                 if (is_typedef_symbol(token.v.symbol)) {
2828                         type = parse_typename();
2829                 } else {
2830                         expression = parse_expression();
2831                         type       = expression->base.type;
2832                 }
2833                 break;
2834
2835         TYPENAME_START
2836                 type = parse_typename();
2837                 break;
2838
2839         default:
2840                 expression = parse_expression();
2841                 type       = expression->base.type;
2842                 break;
2843         }
2844
2845         rem_anchor_token(')');
2846         expect(')');
2847
2848         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF, &expression->base.source_position);
2849         typeof_type->typeoft.expression  = expression;
2850         typeof_type->typeoft.typeof_type = type;
2851
2852         return typeof_type;
2853 end_error:
2854         return NULL;
2855 }
2856
2857 typedef enum specifiers_t {
2858         SPECIFIER_SIGNED    = 1 << 0,
2859         SPECIFIER_UNSIGNED  = 1 << 1,
2860         SPECIFIER_LONG      = 1 << 2,
2861         SPECIFIER_INT       = 1 << 3,
2862         SPECIFIER_DOUBLE    = 1 << 4,
2863         SPECIFIER_CHAR      = 1 << 5,
2864         SPECIFIER_SHORT     = 1 << 6,
2865         SPECIFIER_LONG_LONG = 1 << 7,
2866         SPECIFIER_FLOAT     = 1 << 8,
2867         SPECIFIER_BOOL      = 1 << 9,
2868         SPECIFIER_VOID      = 1 << 10,
2869         SPECIFIER_INT8      = 1 << 11,
2870         SPECIFIER_INT16     = 1 << 12,
2871         SPECIFIER_INT32     = 1 << 13,
2872         SPECIFIER_INT64     = 1 << 14,
2873         SPECIFIER_INT128    = 1 << 15,
2874         SPECIFIER_COMPLEX   = 1 << 16,
2875         SPECIFIER_IMAGINARY = 1 << 17,
2876 } specifiers_t;
2877
2878 static type_t *create_builtin_type(symbol_t *const symbol,
2879                                    type_t *const real_type)
2880 {
2881         type_t *type            = allocate_type_zero(TYPE_BUILTIN, &builtin_source_position);
2882         type->builtin.symbol    = symbol;
2883         type->builtin.real_type = real_type;
2884
2885         type_t *result = typehash_insert(type);
2886         if (type != result) {
2887                 free_type(type);
2888         }
2889
2890         return result;
2891 }
2892
2893 static type_t *get_typedef_type(symbol_t *symbol)
2894 {
2895         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
2896         if (declaration == NULL ||
2897            declaration->storage_class != STORAGE_CLASS_TYPEDEF)
2898                 return NULL;
2899
2900         type_t *type               = allocate_type_zero(TYPE_TYPEDEF, &declaration->source_position);
2901         type->typedeft.declaration = declaration;
2902
2903         return type;
2904 }
2905
2906 /**
2907  * check for the allowed MS alignment values.
2908  */
2909 static bool check_alignment_value(long long intvalue)
2910 {
2911         if (intvalue < 1 || intvalue > 8192) {
2912                 errorf(HERE, "illegal alignment value");
2913                 return false;
2914         }
2915         unsigned v = (unsigned)intvalue;
2916         for(unsigned i = 1; i <= 8192; i += i) {
2917                 if (i == v)
2918                         return true;
2919         }
2920         errorf(HERE, "alignment must be power of two");
2921         return false;
2922 }
2923
2924 #define DET_MOD(name, tag) do { \
2925         if (*modifiers & tag) warningf(HERE, #name " used more than once"); \
2926         *modifiers |= tag; \
2927 } while (0)
2928
2929 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
2930 {
2931         decl_modifiers_t *modifiers = &specifiers->modifiers;
2932
2933         while (true) {
2934                 if (token.type == T_restrict) {
2935                         next_token();
2936                         DET_MOD(restrict, DM_RESTRICT);
2937                         goto end_loop;
2938                 } else if (token.type != T_IDENTIFIER)
2939                         break;
2940                 symbol_t *symbol = token.v.symbol;
2941                 if (symbol == sym_align) {
2942                         next_token();
2943                         expect('(');
2944                         if (token.type != T_INTEGER)
2945                                 goto end_error;
2946                         if (check_alignment_value(token.v.intvalue)) {
2947                                 if (specifiers->alignment != 0)
2948                                         warningf(HERE, "align used more than once");
2949                                 specifiers->alignment = (unsigned char)token.v.intvalue;
2950                         }
2951                         next_token();
2952                         expect(')');
2953                 } else if (symbol == sym_allocate) {
2954                         next_token();
2955                         expect('(');
2956                         if (token.type != T_IDENTIFIER)
2957                                 goto end_error;
2958                         (void)token.v.symbol;
2959                         expect(')');
2960                 } else if (symbol == sym_dllimport) {
2961                         next_token();
2962                         DET_MOD(dllimport, DM_DLLIMPORT);
2963                 } else if (symbol == sym_dllexport) {
2964                         next_token();
2965                         DET_MOD(dllexport, DM_DLLEXPORT);
2966                 } else if (symbol == sym_thread) {
2967                         next_token();
2968                         DET_MOD(thread, DM_THREAD);
2969                 } else if (symbol == sym_naked) {
2970                         next_token();
2971                         DET_MOD(naked, DM_NAKED);
2972                 } else if (symbol == sym_noinline) {
2973                         next_token();
2974                         DET_MOD(noinline, DM_NOINLINE);
2975                 } else if (symbol == sym_noreturn) {
2976                         next_token();
2977                         DET_MOD(noreturn, DM_NORETURN);
2978                 } else if (symbol == sym_nothrow) {
2979                         next_token();
2980                         DET_MOD(nothrow, DM_NOTHROW);
2981                 } else if (symbol == sym_novtable) {
2982                         next_token();
2983                         DET_MOD(novtable, DM_NOVTABLE);
2984                 } else if (symbol == sym_property) {
2985                         next_token();
2986                         expect('(');
2987                         for(;;) {
2988                                 bool is_get = false;
2989                                 if (token.type != T_IDENTIFIER)
2990                                         goto end_error;
2991                                 if (token.v.symbol == sym_get) {
2992                                         is_get = true;
2993                                 } else if (token.v.symbol == sym_put) {
2994                                 } else {
2995                                         errorf(HERE, "Bad property name '%Y'", token.v.symbol);
2996                                         goto end_error;
2997                                 }
2998                                 next_token();
2999                                 expect('=');
3000                                 if (token.type != T_IDENTIFIER)
3001                                         goto end_error;
3002                                 if (is_get) {
3003                                         if (specifiers->get_property_sym != NULL) {
3004                                                 errorf(HERE, "get property name already specified");
3005                                         } else {
3006                                                 specifiers->get_property_sym = token.v.symbol;
3007                                         }
3008                                 } else {
3009                                         if (specifiers->put_property_sym != NULL) {
3010                                                 errorf(HERE, "put property name already specified");
3011                                         } else {
3012                                                 specifiers->put_property_sym = token.v.symbol;
3013                                         }
3014                                 }
3015                                 next_token();
3016                                 if (token.type == ',') {
3017                                         next_token();
3018                                         continue;
3019                                 }
3020                                 break;
3021                         }
3022                         expect(')');
3023                 } else if (symbol == sym_selectany) {
3024                         next_token();
3025                         DET_MOD(selectany, DM_SELECTANY);
3026                 } else if (symbol == sym_uuid) {
3027                         next_token();
3028                         expect('(');
3029                         if (token.type != T_STRING_LITERAL)
3030                                 goto end_error;
3031                         next_token();
3032                         expect(')');
3033                 } else if (symbol == sym_deprecated) {
3034                         next_token();
3035                         if (specifiers->deprecated != 0)
3036                                 warningf(HERE, "deprecated used more than once");
3037                         specifiers->deprecated = 1;
3038                         if (token.type == '(') {
3039                                 next_token();
3040                                 if (token.type == T_STRING_LITERAL) {
3041                                         specifiers->deprecated_string = token.v.string.begin;
3042                                         next_token();
3043                                 } else {
3044                                         errorf(HERE, "string literal expected");
3045                                 }
3046                                 expect(')');
3047                         }
3048                 } else if (symbol == sym_noalias) {
3049                         next_token();
3050                         DET_MOD(noalias, DM_NOALIAS);
3051                 } else {
3052                         warningf(HERE, "Unknown modifier %Y ignored", token.v.symbol);
3053                         next_token();
3054                         if (token.type == '(')
3055                                 skip_until(')');
3056                 }
3057 end_loop:
3058                 if (token.type == ',')
3059                         next_token();
3060         }
3061 end_error:
3062         return;
3063 }
3064
3065 static declaration_t *create_error_declaration(symbol_t *symbol, storage_class_tag_t storage_class)
3066 {
3067         declaration_t *const decl    = allocate_declaration_zero();
3068         decl->source_position        = *HERE;
3069         decl->declared_storage_class = storage_class;
3070         decl->storage_class          =
3071                 storage_class != STORAGE_CLASS_NONE || scope == global_scope ?
3072                         storage_class : STORAGE_CLASS_AUTO;
3073         decl->symbol                 = symbol;
3074         decl->implicit               = true;
3075         record_declaration(decl, false);
3076         return decl;
3077 }
3078
3079 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
3080 {
3081         type_t            *type            = NULL;
3082         type_qualifiers_t  qualifiers      = TYPE_QUALIFIER_NONE;
3083         type_modifiers_t   modifiers       = TYPE_MODIFIER_NONE;
3084         unsigned           type_specifiers = 0;
3085         bool               newtype         = false;
3086         bool               saw_error       = false;
3087
3088         specifiers->source_position = token.source_position;
3089
3090         while (true) {
3091                 specifiers->modifiers
3092                         |= parse_attributes(&specifiers->gnu_attributes);
3093                 if (specifiers->modifiers & DM_TRANSPARENT_UNION)
3094                         modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3095
3096                 switch(token.type) {
3097
3098                 /* storage class */
3099 #define MATCH_STORAGE_CLASS(token, class)                                  \
3100                 case token:                                                        \
3101                         if (specifiers->declared_storage_class != STORAGE_CLASS_NONE) { \
3102                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3103                         }                                                              \
3104                         specifiers->declared_storage_class = class;                    \
3105                         next_token();                                                  \
3106                         break;
3107
3108                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3109                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3110                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3111                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3112                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3113
3114                 case T__declspec:
3115                         next_token();
3116                         expect('(');
3117                         add_anchor_token(')');
3118                         parse_microsoft_extended_decl_modifier(specifiers);
3119                         rem_anchor_token(')');
3120                         expect(')');
3121                         break;
3122
3123                 case T___thread:
3124                         switch (specifiers->declared_storage_class) {
3125                         case STORAGE_CLASS_NONE:
3126                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD;
3127                                 break;
3128
3129                         case STORAGE_CLASS_EXTERN:
3130                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_EXTERN;
3131                                 break;
3132
3133                         case STORAGE_CLASS_STATIC:
3134                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_STATIC;
3135                                 break;
3136
3137                         default:
3138                                 errorf(HERE, "multiple storage classes in declaration specifiers");
3139                                 break;
3140                         }
3141                         next_token();
3142                         break;
3143
3144                 /* type qualifiers */
3145 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3146                 case token:                                                     \
3147                         qualifiers |= qualifier;                                    \
3148                         next_token();                                               \
3149                         break
3150
3151                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3152                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3153                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3154                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3155                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3156                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3157                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3158                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3159
3160                 case T___extension__:
3161                         /* TODO */
3162                         next_token();
3163                         break;
3164
3165                 /* type specifiers */
3166 #define MATCH_SPECIFIER(token, specifier, name)                         \
3167                 case token:                                                     \
3168                         next_token();                                               \
3169                         if (type_specifiers & specifier) {                           \
3170                                 errorf(HERE, "multiple " name " type specifiers given"); \
3171                         } else {                                                    \
3172                                 type_specifiers |= specifier;                           \
3173                         }                                                           \
3174                         break
3175
3176                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3177                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3178                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3179                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3180                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3181                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3182                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3183                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3184                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3185                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3186                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3187                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3188                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3189                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3190                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3191                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3192
3193                 case T__forceinline:
3194                         /* only in microsoft mode */
3195                         specifiers->modifiers |= DM_FORCEINLINE;
3196                         /* FALLTHROUGH */
3197
3198                 case T_inline:
3199                         next_token();
3200                         specifiers->is_inline = true;
3201                         break;
3202
3203                 case T_long:
3204                         next_token();
3205                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3206                                 errorf(HERE, "multiple type specifiers given");
3207                         } else if (type_specifiers & SPECIFIER_LONG) {
3208                                 type_specifiers |= SPECIFIER_LONG_LONG;
3209                         } else {
3210                                 type_specifiers |= SPECIFIER_LONG;
3211                         }
3212                         break;
3213
3214                 case T_struct: {
3215                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT, HERE);
3216
3217                         type->compound.declaration = parse_compound_type_specifier(true);
3218                         break;
3219                 }
3220                 case T_union: {
3221                         type = allocate_type_zero(TYPE_COMPOUND_UNION, HERE);
3222                         type->compound.declaration = parse_compound_type_specifier(false);
3223                         if (type->compound.declaration->modifiers & DM_TRANSPARENT_UNION)
3224                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3225                         break;
3226                 }
3227                 case T_enum:
3228                         type = parse_enum_specifier();
3229                         break;
3230                 case T___typeof__:
3231                         type = parse_typeof();
3232                         break;
3233                 case T___builtin_va_list:
3234                         type = duplicate_type(type_valist);
3235                         next_token();
3236                         break;
3237
3238                 case T_IDENTIFIER: {
3239                         /* only parse identifier if we haven't found a type yet */
3240                         if (type != NULL || type_specifiers != 0) {
3241                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
3242                                  * declaration, so it doesn't generate errors about expecting '(' or
3243                                  * '{' later on. */
3244                                 switch (look_ahead(1)->type) {
3245                                         STORAGE_CLASSES
3246                                         TYPE_SPECIFIERS
3247                                         case T_const:
3248                                         case T_restrict:
3249                                         case T_volatile:
3250                                         case T_inline:
3251                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
3252                                         case T_IDENTIFIER:
3253                                         case '*':
3254                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
3255                                                 next_token();
3256                                                 continue;
3257
3258                                         default:
3259                                                 goto finish_specifiers;
3260                                 }
3261                         }
3262
3263                         type_t *const typedef_type = get_typedef_type(token.v.symbol);
3264                         if (typedef_type == NULL) {
3265                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3266                                  * declaration, so it doesn't generate 'implicit int' followed by more
3267                                  * errors later on. */
3268                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3269                                 switch (la1_type) {
3270                                         DECLARATION_START
3271                                         case T_IDENTIFIER:
3272                                         case '*': {
3273                                                 errorf(HERE, "%K does not name a type", &token);
3274
3275                                                 declaration_t *const decl =
3276                                                         create_error_declaration(token.v.symbol, STORAGE_CLASS_TYPEDEF);
3277
3278                                                 type = allocate_type_zero(TYPE_TYPEDEF, HERE);
3279                                                 type->typedeft.declaration = decl;
3280
3281                                                 next_token();
3282                                                 saw_error = true;
3283                                                 if (la1_type == '*')
3284                                                         goto finish_specifiers;
3285                                                 continue;
3286                                         }
3287
3288                                         default:
3289                                                 goto finish_specifiers;
3290                                 }
3291                         }
3292
3293                         next_token();
3294                         type = typedef_type;
3295                         break;
3296                 }
3297
3298                 /* function specifier */
3299                 default:
3300                         goto finish_specifiers;
3301                 }
3302         }
3303
3304 finish_specifiers:
3305         if (type == NULL || (saw_error && type_specifiers != 0)) {
3306                 atomic_type_kind_t atomic_type;
3307
3308                 /* match valid basic types */
3309                 switch(type_specifiers) {
3310                 case SPECIFIER_VOID:
3311                         atomic_type = ATOMIC_TYPE_VOID;
3312                         break;
3313                 case SPECIFIER_CHAR:
3314                         atomic_type = ATOMIC_TYPE_CHAR;
3315                         break;
3316                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3317                         atomic_type = ATOMIC_TYPE_SCHAR;
3318                         break;
3319                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3320                         atomic_type = ATOMIC_TYPE_UCHAR;
3321                         break;
3322                 case SPECIFIER_SHORT:
3323                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3324                 case SPECIFIER_SHORT | SPECIFIER_INT:
3325                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3326                         atomic_type = ATOMIC_TYPE_SHORT;
3327                         break;
3328                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3329                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3330                         atomic_type = ATOMIC_TYPE_USHORT;
3331                         break;
3332                 case SPECIFIER_INT:
3333                 case SPECIFIER_SIGNED:
3334                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3335                         atomic_type = ATOMIC_TYPE_INT;
3336                         break;
3337                 case SPECIFIER_UNSIGNED:
3338                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3339                         atomic_type = ATOMIC_TYPE_UINT;
3340                         break;
3341                 case SPECIFIER_LONG:
3342                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3343                 case SPECIFIER_LONG | SPECIFIER_INT:
3344                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3345                         atomic_type = ATOMIC_TYPE_LONG;
3346                         break;
3347                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3348                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3349                         atomic_type = ATOMIC_TYPE_ULONG;
3350                         break;
3351
3352                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3353                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3354                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3355                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3356                         | SPECIFIER_INT:
3357                         atomic_type = ATOMIC_TYPE_LONGLONG;
3358                         goto warn_about_long_long;
3359
3360                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3361                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3362                         | SPECIFIER_INT:
3363                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3364 warn_about_long_long:
3365                         if (warning.long_long) {
3366                                 warningf(&specifiers->source_position,
3367                                          "ISO C90 does not support 'long long'");
3368                         }
3369                         break;
3370
3371                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3372                         atomic_type = unsigned_int8_type_kind;
3373                         break;
3374
3375                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3376                         atomic_type = unsigned_int16_type_kind;
3377                         break;
3378
3379                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3380                         atomic_type = unsigned_int32_type_kind;
3381                         break;
3382
3383                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3384                         atomic_type = unsigned_int64_type_kind;
3385                         break;
3386
3387                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3388                         atomic_type = unsigned_int128_type_kind;
3389                         break;
3390
3391                 case SPECIFIER_INT8:
3392                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3393                         atomic_type = int8_type_kind;
3394                         break;
3395
3396                 case SPECIFIER_INT16:
3397                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3398                         atomic_type = int16_type_kind;
3399                         break;
3400
3401                 case SPECIFIER_INT32:
3402                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3403                         atomic_type = int32_type_kind;
3404                         break;
3405
3406                 case SPECIFIER_INT64:
3407                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3408                         atomic_type = int64_type_kind;
3409                         break;
3410
3411                 case SPECIFIER_INT128:
3412                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3413                         atomic_type = int128_type_kind;
3414                         break;
3415
3416                 case SPECIFIER_FLOAT:
3417                         atomic_type = ATOMIC_TYPE_FLOAT;
3418                         break;
3419                 case SPECIFIER_DOUBLE:
3420                         atomic_type = ATOMIC_TYPE_DOUBLE;
3421                         break;
3422                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3423                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3424                         break;
3425                 case SPECIFIER_BOOL:
3426                         atomic_type = ATOMIC_TYPE_BOOL;
3427                         break;
3428                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3429                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3430                         atomic_type = ATOMIC_TYPE_FLOAT;
3431                         break;
3432                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3433                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3434                         atomic_type = ATOMIC_TYPE_DOUBLE;
3435                         break;
3436                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3437                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3438                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3439                         break;
3440                 default:
3441                         /* invalid specifier combination, give an error message */
3442                         if (type_specifiers == 0) {
3443                                 if (saw_error) {
3444                                         specifiers->type = type_error_type;
3445                                         return;
3446                                 }
3447
3448                                 if (!strict_mode) {
3449                                         if (warning.implicit_int) {
3450                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
3451                                         }
3452                                         atomic_type = ATOMIC_TYPE_INT;
3453                                         break;
3454                                 } else {
3455                                         errorf(HERE, "no type specifiers given in declaration");
3456                                 }
3457                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
3458                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
3459                                 errorf(HERE, "signed and unsigned specifiers given");
3460                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
3461                                 errorf(HERE, "only integer types can be signed or unsigned");
3462                         } else {
3463                                 errorf(HERE, "multiple datatypes in declaration");
3464                         }
3465                         atomic_type = ATOMIC_TYPE_INVALID;
3466                 }
3467
3468                 if (type_specifiers & SPECIFIER_COMPLEX &&
3469                    atomic_type != ATOMIC_TYPE_INVALID) {
3470                         type                = allocate_type_zero(TYPE_COMPLEX, &builtin_source_position);
3471                         type->complex.akind = atomic_type;
3472                 } else if (type_specifiers & SPECIFIER_IMAGINARY &&
3473                           atomic_type != ATOMIC_TYPE_INVALID) {
3474                         type                  = allocate_type_zero(TYPE_IMAGINARY, &builtin_source_position);
3475                         type->imaginary.akind = atomic_type;
3476                 } else {
3477                         type               = allocate_type_zero(TYPE_ATOMIC, &builtin_source_position);
3478                         type->atomic.akind = atomic_type;
3479                 }
3480                 newtype = true;
3481         } else if (type_specifiers != 0) {
3482                 errorf(HERE, "multiple datatypes in declaration");
3483         }
3484
3485         /* FIXME: check type qualifiers here */
3486
3487         type->base.qualifiers = qualifiers;
3488         type->base.modifiers  = modifiers;
3489
3490         type_t *result = typehash_insert(type);
3491         if (newtype && result != type) {
3492                 free_type(type);
3493         }
3494
3495         specifiers->type = result;
3496 end_error:
3497         return;
3498 }
3499
3500 static type_qualifiers_t parse_type_qualifiers(void)
3501 {
3502         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
3503
3504         while (true) {
3505                 switch(token.type) {
3506                 /* type qualifiers */
3507                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3508                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3509                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3510                 /* microsoft extended type modifiers */
3511                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3512                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3513                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3514                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3515                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3516
3517                 default:
3518                         return qualifiers;
3519                 }
3520         }
3521 }
3522
3523 static declaration_t *parse_identifier_list(void)
3524 {
3525         declaration_t *declarations     = NULL;
3526         declaration_t *last_declaration = NULL;
3527         do {
3528                 declaration_t *const declaration = allocate_declaration_zero();
3529                 declaration->type            = NULL; /* a K&R parameter list has no types, yet */
3530                 declaration->source_position = token.source_position;
3531                 declaration->symbol          = token.v.symbol;
3532                 next_token();
3533
3534                 if (last_declaration != NULL) {
3535                         last_declaration->next = declaration;
3536                 } else {
3537                         declarations = declaration;
3538                 }
3539                 last_declaration = declaration;
3540
3541                 if (token.type != ',') {
3542                         break;
3543                 }
3544                 next_token();
3545         } while (token.type == T_IDENTIFIER);
3546
3547         return declarations;
3548 }
3549
3550 static type_t *automatic_type_conversion(type_t *orig_type);
3551
3552 static void semantic_parameter(declaration_t *declaration)
3553 {
3554         /* TODO: improve error messages */
3555         source_position_t const* const pos = &declaration->source_position;
3556
3557         switch (declaration->declared_storage_class) {
3558                 case STORAGE_CLASS_TYPEDEF:
3559                         errorf(pos, "typedef not allowed in parameter list");
3560                         break;
3561
3562                 /* Allowed storage classes */
3563                 case STORAGE_CLASS_NONE:
3564                 case STORAGE_CLASS_REGISTER:
3565                         break;
3566
3567                 default:
3568                         errorf(pos, "parameter may only have none or register storage class");
3569                         break;
3570         }
3571
3572         type_t *const orig_type = declaration->type;
3573         /* §6.7.5.3(7): Array as last part of a parameter type is just syntactic
3574          * sugar.  Turn it into a pointer.
3575          * §6.7.5.3(8): A declaration of a parameter as ``function returning type''
3576          * shall be adjusted to ``pointer to function returning type'', as in 6.3.2.1.
3577          */
3578         type_t *const type = automatic_type_conversion(orig_type);
3579         declaration->type = type;
3580
3581         if (is_type_incomplete(skip_typeref(type))) {
3582                 errorf(pos, "parameter '%#T' is of incomplete type",
3583                        orig_type, declaration->symbol);
3584         }
3585 }
3586
3587 static declaration_t *parse_parameter(void)
3588 {
3589         declaration_specifiers_t specifiers;
3590         memset(&specifiers, 0, sizeof(specifiers));
3591
3592         parse_declaration_specifiers(&specifiers);
3593
3594         declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/true);
3595
3596         return declaration;
3597 }
3598
3599 static declaration_t *parse_parameters(function_type_t *type)
3600 {
3601         declaration_t *declarations = NULL;
3602
3603         eat('(');
3604         add_anchor_token(')');
3605         int saved_comma_state = save_and_reset_anchor_state(',');
3606
3607         if (token.type == T_IDENTIFIER &&
3608             !is_typedef_symbol(token.v.symbol)) {
3609                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
3610                 if (la1_type == ',' || la1_type == ')') {
3611                         type->kr_style_parameters = true;
3612                         declarations = parse_identifier_list();
3613                         goto parameters_finished;
3614                 }
3615         }
3616
3617         if (token.type == ')') {
3618                 type->unspecified_parameters = 1;
3619                 goto parameters_finished;
3620         }
3621
3622         declaration_t        *declaration;
3623         declaration_t        *last_declaration = NULL;
3624         function_parameter_t *parameter;
3625         function_parameter_t *last_parameter = NULL;
3626
3627         while (true) {
3628                 switch(token.type) {
3629                 case T_DOTDOTDOT:
3630                         next_token();
3631                         type->variadic = 1;
3632                         goto parameters_finished;
3633
3634                 case T_IDENTIFIER:
3635                 case T___extension__:
3636                 DECLARATION_START
3637                         declaration = parse_parameter();
3638
3639                         /* func(void) is not a parameter */
3640                         if (last_parameter == NULL
3641                                         && token.type == ')'
3642                                         && declaration->symbol == NULL
3643                                         && skip_typeref(declaration->type) == type_void) {
3644                                 goto parameters_finished;
3645                         }
3646                         semantic_parameter(declaration);
3647
3648                         parameter       = obstack_alloc(type_obst, sizeof(parameter[0]));
3649                         memset(parameter, 0, sizeof(parameter[0]));
3650                         parameter->type = declaration->type;
3651
3652                         if (last_parameter != NULL) {
3653                                 last_declaration->next = declaration;
3654                                 last_parameter->next   = parameter;
3655                         } else {
3656                                 type->parameters = parameter;
3657                                 declarations     = declaration;
3658                         }
3659                         last_parameter   = parameter;
3660                         last_declaration = declaration;
3661                         break;
3662
3663                 default:
3664                         goto parameters_finished;
3665                 }
3666                 if (token.type != ',') {
3667                         goto parameters_finished;
3668                 }
3669                 next_token();
3670         }
3671
3672
3673 parameters_finished:
3674         rem_anchor_token(')');
3675         expect(')');
3676
3677         restore_anchor_state(',', saved_comma_state);
3678         return declarations;
3679
3680 end_error:
3681         restore_anchor_state(',', saved_comma_state);
3682         return NULL;
3683 }
3684
3685 typedef enum construct_type_kind_t {
3686         CONSTRUCT_INVALID,
3687         CONSTRUCT_POINTER,
3688         CONSTRUCT_FUNCTION,
3689         CONSTRUCT_ARRAY
3690 } construct_type_kind_t;
3691
3692 typedef struct construct_type_t construct_type_t;
3693 struct construct_type_t {
3694         construct_type_kind_t  kind;
3695         construct_type_t      *next;
3696 };
3697
3698 typedef struct parsed_pointer_t parsed_pointer_t;
3699 struct parsed_pointer_t {
3700         construct_type_t  construct_type;
3701         type_qualifiers_t type_qualifiers;
3702 };
3703
3704 typedef struct construct_function_type_t construct_function_type_t;
3705 struct construct_function_type_t {
3706         construct_type_t  construct_type;
3707         type_t           *function_type;
3708 };
3709
3710 typedef struct parsed_array_t parsed_array_t;
3711 struct parsed_array_t {
3712         construct_type_t  construct_type;
3713         type_qualifiers_t type_qualifiers;
3714         bool              is_static;
3715         bool              is_variable;
3716         expression_t     *size;
3717 };
3718
3719 typedef struct construct_base_type_t construct_base_type_t;
3720 struct construct_base_type_t {
3721         construct_type_t  construct_type;
3722         type_t           *type;
3723 };
3724
3725 static construct_type_t *parse_pointer_declarator(void)
3726 {
3727         eat('*');
3728
3729         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
3730         memset(pointer, 0, sizeof(pointer[0]));
3731         pointer->construct_type.kind = CONSTRUCT_POINTER;
3732         pointer->type_qualifiers     = parse_type_qualifiers();
3733
3734         return (construct_type_t*) pointer;
3735 }
3736
3737 static construct_type_t *parse_array_declarator(void)
3738 {
3739         eat('[');
3740         add_anchor_token(']');
3741
3742         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
3743         memset(array, 0, sizeof(array[0]));
3744         array->construct_type.kind = CONSTRUCT_ARRAY;
3745
3746         if (token.type == T_static) {
3747                 array->is_static = true;
3748                 next_token();
3749         }
3750
3751         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
3752         if (type_qualifiers != 0) {
3753                 if (token.type == T_static) {
3754                         array->is_static = true;
3755                         next_token();
3756                 }
3757         }
3758         array->type_qualifiers = type_qualifiers;
3759
3760         if (token.type == '*' && look_ahead(1)->type == ']') {
3761                 array->is_variable = true;
3762                 next_token();
3763         } else if (token.type != ']') {
3764                 array->size = parse_assignment_expression();
3765         }
3766
3767         rem_anchor_token(']');
3768         expect(']');
3769
3770         return (construct_type_t*) array;
3771 end_error:
3772         return NULL;
3773 }
3774
3775 static construct_type_t *parse_function_declarator(declaration_t *declaration)
3776 {
3777         type_t *type;
3778         if (declaration != NULL) {
3779                 type = allocate_type_zero(TYPE_FUNCTION, &declaration->source_position);
3780
3781                 unsigned mask = declaration->modifiers & (DM_CDECL|DM_STDCALL|DM_FASTCALL|DM_THISCALL);
3782
3783                 if (mask & (mask-1)) {
3784                         const char *first = NULL, *second = NULL;
3785
3786                         /* more than one calling convention set */
3787                         if (declaration->modifiers & DM_CDECL) {
3788                                 if (first == NULL)       first = "cdecl";
3789                                 else if (second == NULL) second = "cdecl";
3790                         }
3791                         if (declaration->modifiers & DM_STDCALL) {
3792                                 if (first == NULL)       first = "stdcall";
3793                                 else if (second == NULL) second = "stdcall";
3794                         }
3795                         if (declaration->modifiers & DM_FASTCALL) {
3796                                 if (first == NULL)       first = "fastcall";
3797                                 else if (second == NULL) second = "fastcall";
3798                         }
3799                         if (declaration->modifiers & DM_THISCALL) {
3800                                 if (first == NULL)       first = "thiscall";
3801                                 else if (second == NULL) second = "thiscall";
3802                         }
3803                         errorf(&declaration->source_position, "%s and %s attributes are not compatible", first, second);
3804                 }
3805
3806                 if (declaration->modifiers & DM_CDECL)
3807                         type->function.calling_convention = CC_CDECL;
3808                 else if (declaration->modifiers & DM_STDCALL)
3809                         type->function.calling_convention = CC_STDCALL;
3810                 else if (declaration->modifiers & DM_FASTCALL)
3811                         type->function.calling_convention = CC_FASTCALL;
3812                 else if (declaration->modifiers & DM_THISCALL)
3813                         type->function.calling_convention = CC_THISCALL;
3814         } else {
3815                 type = allocate_type_zero(TYPE_FUNCTION, HERE);
3816         }
3817
3818         declaration_t *parameters = parse_parameters(&type->function);
3819         if (declaration != NULL) {
3820                 declaration->scope.declarations = parameters;
3821         }
3822
3823         construct_function_type_t *construct_function_type =
3824                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
3825         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
3826         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
3827         construct_function_type->function_type       = type;
3828
3829         return &construct_function_type->construct_type;
3830 }
3831
3832 static void fix_declaration_type(declaration_t *declaration)
3833 {
3834         decl_modifiers_t declaration_modifiers = declaration->modifiers;
3835         type_modifiers_t type_modifiers        = declaration->type->base.modifiers;
3836
3837         if (declaration_modifiers & DM_TRANSPARENT_UNION)
3838                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3839
3840         if (declaration->type->base.modifiers == type_modifiers)
3841                 return;
3842
3843         type_t *copy = duplicate_type(declaration->type);
3844         copy->base.modifiers = type_modifiers;
3845
3846         type_t *result = typehash_insert(copy);
3847         if (result != copy) {
3848                 obstack_free(type_obst, copy);
3849         }
3850
3851         declaration->type = result;
3852 }
3853
3854 static construct_type_t *parse_inner_declarator(declaration_t *declaration,
3855                 bool may_be_abstract)
3856 {
3857         /* construct a single linked list of construct_type_t's which describe
3858          * how to construct the final declarator type */
3859         construct_type_t *first = NULL;
3860         construct_type_t *last  = NULL;
3861         gnu_attribute_t  *attributes = NULL;
3862
3863         decl_modifiers_t modifiers = parse_attributes(&attributes);
3864
3865         /* pointers */
3866         while (token.type == '*') {
3867                 construct_type_t *type = parse_pointer_declarator();
3868
3869                 if (last == NULL) {
3870                         first = type;
3871                         last  = type;
3872                 } else {
3873                         last->next = type;
3874                         last       = type;
3875                 }
3876
3877                 /* TODO: find out if this is correct */
3878                 modifiers |= parse_attributes(&attributes);
3879         }
3880
3881         if (declaration != NULL)
3882                 declaration->modifiers |= modifiers;
3883
3884         construct_type_t *inner_types = NULL;
3885
3886         switch(token.type) {
3887         case T_IDENTIFIER:
3888                 if (declaration == NULL) {
3889                         errorf(HERE, "no identifier expected in typename");
3890                 } else {
3891                         declaration->symbol          = token.v.symbol;
3892                         declaration->source_position = token.source_position;
3893                 }
3894                 next_token();
3895                 break;
3896         case '(':
3897                 next_token();
3898                 add_anchor_token(')');
3899                 inner_types = parse_inner_declarator(declaration, may_be_abstract);
3900                 /* All later declarators only modify the return type, not declaration */
3901                 declaration = NULL;
3902                 rem_anchor_token(')');
3903                 expect(')');
3904                 break;
3905         default:
3906                 if (may_be_abstract)
3907                         break;
3908                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
3909                 /* avoid a loop in the outermost scope, because eat_statement doesn't
3910                  * eat '}' */
3911                 if (token.type == '}' && current_function == NULL) {
3912                         next_token();
3913                 } else {
3914                         eat_statement();
3915                 }
3916                 return NULL;
3917         }
3918
3919         construct_type_t *p = last;
3920
3921         while(true) {
3922                 construct_type_t *type;
3923                 switch(token.type) {
3924                 case '(':
3925                         type = parse_function_declarator(declaration);
3926                         break;
3927                 case '[':
3928                         type = parse_array_declarator();
3929                         break;
3930                 default:
3931                         goto declarator_finished;
3932                 }
3933
3934                 /* insert in the middle of the list (behind p) */
3935                 if (p != NULL) {
3936                         type->next = p->next;
3937                         p->next    = type;
3938                 } else {
3939                         type->next = first;
3940                         first      = type;
3941                 }
3942                 if (last == p) {
3943                         last = type;
3944                 }
3945         }
3946
3947 declarator_finished:
3948         /* append inner_types at the end of the list, we don't to set last anymore
3949          * as it's not needed anymore */
3950         if (last == NULL) {
3951                 assert(first == NULL);
3952                 first = inner_types;
3953         } else {
3954                 last->next = inner_types;
3955         }
3956
3957         return first;
3958 end_error:
3959         return NULL;
3960 }
3961
3962 static void parse_declaration_attributes(declaration_t *declaration)
3963 {
3964         gnu_attribute_t  *attributes = NULL;
3965         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
3966
3967         if (declaration == NULL)
3968                 return;
3969
3970         declaration->modifiers |= modifiers;
3971         /* check if we have these stupid mode attributes... */
3972         type_t *old_type = declaration->type;
3973         if (old_type == NULL)
3974                 return;
3975
3976         gnu_attribute_t *attribute = attributes;
3977         for ( ; attribute != NULL; attribute = attribute->next) {
3978                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
3979                         continue;
3980
3981                 atomic_type_kind_t  akind = attribute->u.akind;
3982                 if (!is_type_signed(old_type)) {
3983                         switch(akind) {
3984                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
3985                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
3986                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
3987                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
3988                         default:
3989                                 panic("invalid akind in mode attribute");
3990                         }
3991                 }
3992                 declaration->type
3993                         = make_atomic_type(akind, old_type->base.qualifiers);
3994         }
3995 }
3996
3997 static type_t *construct_declarator_type(construct_type_t *construct_list,
3998                                          type_t *type)
3999 {
4000         construct_type_t *iter = construct_list;
4001         for( ; iter != NULL; iter = iter->next) {
4002                 switch(iter->kind) {
4003                 case CONSTRUCT_INVALID:
4004                         internal_errorf(HERE, "invalid type construction found");
4005                 case CONSTRUCT_FUNCTION: {
4006                         construct_function_type_t *construct_function_type
4007                                 = (construct_function_type_t*) iter;
4008
4009                         type_t *function_type = construct_function_type->function_type;
4010
4011                         function_type->function.return_type = type;
4012
4013                         type_t *skipped_return_type = skip_typeref(type);
4014                         if (is_type_function(skipped_return_type)) {
4015                                 errorf(HERE, "function returning function is not allowed");
4016                                 type = type_error_type;
4017                         } else if (is_type_array(skipped_return_type)) {
4018                                 errorf(HERE, "function returning array is not allowed");
4019                                 type = type_error_type;
4020                         } else {
4021                                 type = function_type;
4022                         }
4023                         break;
4024                 }
4025
4026                 case CONSTRUCT_POINTER: {
4027                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
4028                         type_t           *pointer_type   = allocate_type_zero(TYPE_POINTER, &null_position);
4029                         pointer_type->pointer.points_to  = type;
4030                         pointer_type->base.qualifiers    = parsed_pointer->type_qualifiers;
4031
4032                         type = pointer_type;
4033                         break;
4034                 }
4035
4036                 case CONSTRUCT_ARRAY: {
4037                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
4038                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY, &null_position);
4039
4040                         expression_t *size_expression = parsed_array->size;
4041                         if (size_expression != NULL) {
4042                                 size_expression
4043                                         = create_implicit_cast(size_expression, type_size_t);
4044                         }
4045
4046                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
4047                         array_type->array.element_type    = type;
4048                         array_type->array.is_static       = parsed_array->is_static;
4049                         array_type->array.is_variable     = parsed_array->is_variable;
4050                         array_type->array.size_expression = size_expression;
4051
4052                         if (size_expression != NULL) {
4053                                 if (is_constant_expression(size_expression)) {
4054                                         array_type->array.size_constant = true;
4055                                         array_type->array.size
4056                                                 = fold_constant(size_expression);
4057                                 } else {
4058                                         array_type->array.is_vla = true;
4059                                 }
4060                         }
4061
4062                         type_t *skipped_type = skip_typeref(type);
4063                         if (is_type_atomic(skipped_type, ATOMIC_TYPE_VOID)) {
4064                                 errorf(HERE, "array of void is not allowed");
4065                                 type = type_error_type;
4066                         } else {
4067                                 type = array_type;
4068                         }
4069                         break;
4070                 }
4071                 }
4072
4073                 type_t *hashed_type = typehash_insert(type);
4074                 if (hashed_type != type) {
4075                         /* the function type was constructed earlier freeing it here will
4076                          * destroy other types... */
4077                         if (iter->kind != CONSTRUCT_FUNCTION) {
4078                                 free_type(type);
4079                         }
4080                         type = hashed_type;
4081                 }
4082         }
4083
4084         return type;
4085 }
4086
4087 static declaration_t *parse_declarator(
4088                 const declaration_specifiers_t *specifiers, bool may_be_abstract)
4089 {
4090         declaration_t *const declaration    = allocate_declaration_zero();
4091         declaration->source_position        = specifiers->source_position;
4092         declaration->declared_storage_class = specifiers->declared_storage_class;
4093         declaration->modifiers              = specifiers->modifiers;
4094         declaration->deprecated_string      = specifiers->deprecated_string;
4095         declaration->get_property_sym       = specifiers->get_property_sym;
4096         declaration->put_property_sym       = specifiers->put_property_sym;
4097         declaration->is_inline              = specifiers->is_inline;
4098
4099         declaration->storage_class          = specifiers->declared_storage_class;
4100         if (declaration->storage_class == STORAGE_CLASS_NONE
4101                         && scope != global_scope) {
4102                 declaration->storage_class = STORAGE_CLASS_AUTO;
4103         }
4104
4105         if (specifiers->alignment != 0) {
4106                 /* TODO: add checks here */
4107                 declaration->alignment = specifiers->alignment;
4108         }
4109
4110         construct_type_t *construct_type
4111                 = parse_inner_declarator(declaration, may_be_abstract);
4112         type_t *const type = specifiers->type;
4113         declaration->type = construct_declarator_type(construct_type, type);
4114
4115         parse_declaration_attributes(declaration);
4116
4117         fix_declaration_type(declaration);
4118
4119         if (construct_type != NULL) {
4120                 obstack_free(&temp_obst, construct_type);
4121         }
4122
4123         return declaration;
4124 }
4125
4126 static type_t *parse_abstract_declarator(type_t *base_type)
4127 {
4128         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4129
4130         type_t *result = construct_declarator_type(construct_type, base_type);
4131         if (construct_type != NULL) {
4132                 obstack_free(&temp_obst, construct_type);
4133         }
4134
4135         return result;
4136 }
4137
4138 static declaration_t *append_declaration(declaration_t* const declaration)
4139 {
4140         if (last_declaration != NULL) {
4141                 last_declaration->next = declaration;
4142         } else {
4143                 scope->declarations = declaration;
4144         }
4145         last_declaration = declaration;
4146         return declaration;
4147 }
4148
4149 /**
4150  * Check if the declaration of main is suspicious.  main should be a
4151  * function with external linkage, returning int, taking either zero
4152  * arguments, two, or three arguments of appropriate types, ie.
4153  *
4154  * int main([ int argc, char **argv [, char **env ] ]).
4155  *
4156  * @param decl    the declaration to check
4157  * @param type    the function type of the declaration
4158  */
4159 static void check_type_of_main(const declaration_t *const decl, const function_type_t *const func_type)
4160 {
4161         if (decl->storage_class == STORAGE_CLASS_STATIC) {
4162                 warningf(&decl->source_position,
4163                          "'main' is normally a non-static function");
4164         }
4165         if (skip_typeref(func_type->return_type) != type_int) {
4166                 warningf(&decl->source_position,
4167                          "return type of 'main' should be 'int', but is '%T'",
4168                          func_type->return_type);
4169         }
4170         const function_parameter_t *parm = func_type->parameters;
4171         if (parm != NULL) {
4172                 type_t *const first_type = parm->type;
4173                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4174                         warningf(&decl->source_position,
4175                                  "first argument of 'main' should be 'int', but is '%T'", first_type);
4176                 }
4177                 parm = parm->next;
4178                 if (parm != NULL) {
4179                         type_t *const second_type = parm->type;
4180                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4181                                 warningf(&decl->source_position,
4182                                          "second argument of 'main' should be 'char**', but is '%T'", second_type);
4183                         }
4184                         parm = parm->next;
4185                         if (parm != NULL) {
4186                                 type_t *const third_type = parm->type;
4187                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4188                                         warningf(&decl->source_position,
4189                                                  "third argument of 'main' should be 'char**', but is '%T'", third_type);
4190                                 }
4191                                 parm = parm->next;
4192                                 if (parm != NULL)
4193                                         goto warn_arg_count;
4194                         }
4195                 } else {
4196 warn_arg_count:
4197                         warningf(&decl->source_position, "'main' takes only zero, two or three arguments");
4198                 }
4199         }
4200 }
4201
4202 /**
4203  * Check if a symbol is the equal to "main".
4204  */
4205 static bool is_sym_main(const symbol_t *const sym)
4206 {
4207         return strcmp(sym->string, "main") == 0;
4208 }
4209
4210 static declaration_t *record_declaration(
4211         declaration_t *const declaration,
4212         const bool is_definition)
4213 {
4214         const symbol_t *const symbol  = declaration->symbol;
4215         const namespace_t     namespc = (namespace_t)declaration->namespc;
4216
4217         assert(symbol != NULL);
4218         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4219
4220         type_t *const orig_type = declaration->type;
4221         type_t *const type      = skip_typeref(orig_type);
4222         if (is_type_function(type) &&
4223                         type->function.unspecified_parameters &&
4224                         warning.strict_prototypes &&
4225                         previous_declaration == NULL) {
4226                 warningf(&declaration->source_position,
4227                          "function declaration '%#T' is not a prototype",
4228                          orig_type, declaration->symbol);
4229         }
4230
4231         if (warning.main && is_type_function(type) && is_sym_main(symbol)) {
4232                 check_type_of_main(declaration, &type->function);
4233         }
4234
4235         if (warning.nested_externs                             &&
4236             declaration->storage_class == STORAGE_CLASS_EXTERN &&
4237             scope                      != global_scope) {
4238                 warningf(&declaration->source_position,
4239                          "nested extern declaration of '%#T'", declaration->type, symbol);
4240         }
4241
4242         assert(declaration != previous_declaration);
4243         if (previous_declaration != NULL
4244                         && previous_declaration->parent_scope == scope) {
4245                 /* can happen for K&R style declarations */
4246                 if (previous_declaration->type == NULL) {
4247                         previous_declaration->type = declaration->type;
4248                 }
4249
4250                 const type_t *prev_type = skip_typeref(previous_declaration->type);
4251                 if (!types_compatible(type, prev_type)) {
4252                         errorf(&declaration->source_position,
4253                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
4254                                    orig_type, symbol, previous_declaration->type, symbol,
4255                                    &previous_declaration->source_position);
4256                 } else {
4257                         unsigned old_storage_class = previous_declaration->storage_class;
4258                         if (old_storage_class == STORAGE_CLASS_ENUM_ENTRY) {
4259                                 errorf(&declaration->source_position,
4260                                            "redeclaration of enum entry '%Y' (declared %P)",
4261                                            symbol, &previous_declaration->source_position);
4262                                 return previous_declaration;
4263                         }
4264
4265                         if (warning.redundant_decls                                     &&
4266                             is_definition                                               &&
4267                             previous_declaration->storage_class == STORAGE_CLASS_STATIC &&
4268                             !(previous_declaration->modifiers & DM_USED)                &&
4269                             !previous_declaration->used) {
4270                                 warningf(&previous_declaration->source_position,
4271                                          "unnecessary static forward declaration for '%#T'",
4272                                          previous_declaration->type, symbol);
4273                         }
4274
4275                         unsigned new_storage_class = declaration->storage_class;
4276
4277                         if (is_type_incomplete(prev_type)) {
4278                                 previous_declaration->type = type;
4279                                 prev_type                  = type;
4280                         }
4281
4282                         /* pretend no storage class means extern for function
4283                          * declarations (except if the previous declaration is neither
4284                          * none nor extern) */
4285                         if (is_type_function(type)) {
4286                                 if (prev_type->function.unspecified_parameters) {
4287                                         previous_declaration->type = type;
4288                                         prev_type                  = type;
4289                                 }
4290
4291                                 switch (old_storage_class) {
4292                                 case STORAGE_CLASS_NONE:
4293                                         old_storage_class = STORAGE_CLASS_EXTERN;
4294                                         /* FALLTHROUGH */
4295
4296                                 case STORAGE_CLASS_EXTERN:
4297                                         if (is_definition) {
4298                                                 if (warning.missing_prototypes &&
4299                                                     prev_type->function.unspecified_parameters &&
4300                                                     !is_sym_main(symbol)) {
4301                                                         warningf(&declaration->source_position,
4302                                                                          "no previous prototype for '%#T'",
4303                                                                          orig_type, symbol);
4304                                                 }
4305                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4306                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4307                                         }
4308                                         break;
4309
4310                                 default:
4311                                         break;
4312                                 }
4313                         }
4314
4315                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
4316                                         new_storage_class == STORAGE_CLASS_EXTERN) {
4317 warn_redundant_declaration:
4318                                 if (!is_definition          &&
4319                                     warning.redundant_decls &&
4320                                     strcmp(previous_declaration->source_position.input_name, "<builtin>") != 0) {
4321                                         warningf(&declaration->source_position,
4322                                                  "redundant declaration for '%Y' (declared %P)",
4323                                                  symbol, &previous_declaration->source_position);
4324                                 }
4325                         } else if (current_function == NULL) {
4326                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
4327                                     new_storage_class == STORAGE_CLASS_STATIC) {
4328                                         errorf(&declaration->source_position,
4329                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
4330                                                symbol, &previous_declaration->source_position);
4331                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4332                                         previous_declaration->storage_class          = STORAGE_CLASS_NONE;
4333                                         previous_declaration->declared_storage_class = STORAGE_CLASS_NONE;
4334                                 } else {
4335                                         goto warn_redundant_declaration;
4336                                 }
4337                         } else if (old_storage_class == new_storage_class) {
4338                                 errorf(&declaration->source_position,
4339                                        "redeclaration of '%Y' (declared %P)",
4340                                        symbol, &previous_declaration->source_position);
4341                         } else {
4342                                 errorf(&declaration->source_position,
4343                                        "redeclaration of '%Y' with different linkage (declared %P)",
4344                                        symbol, &previous_declaration->source_position);
4345                         }
4346                 }
4347
4348                 previous_declaration->modifiers |= declaration->modifiers;
4349                 previous_declaration->is_inline |= declaration->is_inline;
4350                 return previous_declaration;
4351         } else if (is_type_function(type)) {
4352                 if (is_definition &&
4353                     declaration->storage_class != STORAGE_CLASS_STATIC) {
4354                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4355                                 warningf(&declaration->source_position,
4356                                          "no previous prototype for '%#T'", orig_type, symbol);
4357                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4358                                 warningf(&declaration->source_position,
4359                                          "no previous declaration for '%#T'", orig_type,
4360                                          symbol);
4361                         }
4362                 }
4363         } else {
4364                 if (warning.missing_declarations &&
4365                     scope == global_scope && (
4366                       declaration->storage_class == STORAGE_CLASS_NONE ||
4367                       declaration->storage_class == STORAGE_CLASS_THREAD
4368                     )) {
4369                         warningf(&declaration->source_position,
4370                                  "no previous declaration for '%#T'", orig_type, symbol);
4371                 }
4372         }
4373
4374         assert(declaration->parent_scope == NULL);
4375         assert(scope != NULL);
4376
4377         declaration->parent_scope = scope;
4378
4379         environment_push(declaration);
4380         return append_declaration(declaration);
4381 }
4382
4383 static void parser_error_multiple_definition(declaration_t *declaration,
4384                 const source_position_t *source_position)
4385 {
4386         errorf(source_position, "multiple definition of symbol '%Y' (declared %P)",
4387                declaration->symbol, &declaration->source_position);
4388 }
4389
4390 static bool is_declaration_specifier(const token_t *token,
4391                                      bool only_specifiers_qualifiers)
4392 {
4393         switch(token->type) {
4394                 TYPE_SPECIFIERS
4395                 TYPE_QUALIFIERS
4396                         return true;
4397                 case T_IDENTIFIER:
4398                         return is_typedef_symbol(token->v.symbol);
4399
4400                 case T___extension__:
4401                 STORAGE_CLASSES
4402                         return !only_specifiers_qualifiers;
4403
4404                 default:
4405                         return false;
4406         }
4407 }
4408
4409 static void parse_init_declarator_rest(declaration_t *declaration)
4410 {
4411         eat('=');
4412
4413         type_t *orig_type = declaration->type;
4414         type_t *type      = skip_typeref(orig_type);
4415
4416         if (declaration->init.initializer != NULL) {
4417                 parser_error_multiple_definition(declaration, HERE);
4418         }
4419
4420         bool must_be_constant = false;
4421         if (declaration->storage_class == STORAGE_CLASS_STATIC
4422                         || declaration->storage_class == STORAGE_CLASS_THREAD_STATIC
4423                         || declaration->parent_scope == global_scope) {
4424                 must_be_constant = true;
4425         }
4426
4427         if (is_type_function(type)) {
4428                 errorf(&declaration->source_position,
4429                        "function '%#T' is initialized like a variable",
4430                        orig_type, declaration->symbol);
4431                 orig_type = type_error_type;
4432         }
4433
4434         parse_initializer_env_t env;
4435         env.type             = orig_type;
4436         env.must_be_constant = must_be_constant;
4437         env.declaration      = current_init_decl = declaration;
4438
4439         initializer_t *initializer = parse_initializer(&env);
4440         current_init_decl = NULL;
4441
4442         if (!is_type_function(type)) {
4443                 /* § 6.7.5 (22)  array initializers for arrays with unknown size determine
4444                  * the array type size */
4445                 declaration->type             = env.type;
4446                 declaration->init.initializer = initializer;
4447         }
4448 }
4449
4450 /* parse rest of a declaration without any declarator */
4451 static void parse_anonymous_declaration_rest(
4452                 const declaration_specifiers_t *specifiers)
4453 {
4454         eat(';');
4455
4456         declaration_t *const declaration    = allocate_declaration_zero();
4457         declaration->type                   = specifiers->type;
4458         declaration->declared_storage_class = specifiers->declared_storage_class;
4459         declaration->source_position        = specifiers->source_position;
4460         declaration->modifiers              = specifiers->modifiers;
4461
4462         if (declaration->declared_storage_class != STORAGE_CLASS_NONE) {
4463                 warningf(&declaration->source_position,
4464                          "useless storage class in empty declaration");
4465         }
4466         declaration->storage_class = STORAGE_CLASS_NONE;
4467
4468         type_t *type = declaration->type;
4469         switch (type->kind) {
4470                 case TYPE_COMPOUND_STRUCT:
4471                 case TYPE_COMPOUND_UNION: {
4472                         if (type->compound.declaration->symbol == NULL) {
4473                                 warningf(&declaration->source_position,
4474                                          "unnamed struct/union that defines no instances");
4475                         }
4476                         break;
4477                 }
4478
4479                 case TYPE_ENUM:
4480                         break;
4481
4482                 default:
4483                         warningf(&declaration->source_position, "empty declaration");
4484                         break;
4485         }
4486
4487         append_declaration(declaration);
4488 }
4489
4490 static void parse_declaration_rest(declaration_t *ndeclaration,
4491                 const declaration_specifiers_t *specifiers,
4492                 parsed_declaration_func finished_declaration)
4493 {
4494         add_anchor_token(';');
4495         add_anchor_token('=');
4496         add_anchor_token(',');
4497         while(true) {
4498                 declaration_t *declaration =
4499                         finished_declaration(ndeclaration, token.type == '=');
4500
4501                 type_t *orig_type = declaration->type;
4502                 type_t *type      = skip_typeref(orig_type);
4503
4504                 if (type->kind != TYPE_FUNCTION &&
4505                     declaration->is_inline &&
4506                     is_type_valid(type)) {
4507                         warningf(&declaration->source_position,
4508                                  "variable '%Y' declared 'inline'\n", declaration->symbol);
4509                 }
4510
4511                 if (token.type == '=') {
4512                         parse_init_declarator_rest(declaration);
4513                 }
4514
4515                 if (token.type != ',')
4516                         break;
4517                 eat(',');
4518
4519                 ndeclaration = parse_declarator(specifiers, /*may_be_abstract=*/false);
4520         }
4521         expect(';');
4522
4523 end_error:
4524         rem_anchor_token(';');
4525         rem_anchor_token('=');
4526         rem_anchor_token(',');
4527 }
4528
4529 static declaration_t *finished_kr_declaration(declaration_t *declaration, bool is_definition)
4530 {
4531         symbol_t *symbol  = declaration->symbol;
4532         if (symbol == NULL) {
4533                 errorf(HERE, "anonymous declaration not valid as function parameter");
4534                 return declaration;
4535         }
4536         namespace_t namespc = (namespace_t) declaration->namespc;
4537         if (namespc != NAMESPACE_NORMAL) {
4538                 return record_declaration(declaration, false);
4539         }
4540
4541         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4542         if (previous_declaration == NULL ||
4543                         previous_declaration->parent_scope != scope) {
4544                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
4545                        symbol);
4546                 return declaration;
4547         }
4548
4549         if (is_definition) {
4550                 errorf(HERE, "parameter %Y is initialised", declaration->symbol);
4551         }
4552
4553         if (previous_declaration->type == NULL) {
4554                 previous_declaration->type          = declaration->type;
4555                 previous_declaration->declared_storage_class = declaration->declared_storage_class;
4556                 previous_declaration->storage_class = declaration->storage_class;
4557                 previous_declaration->parent_scope  = scope;
4558                 return previous_declaration;
4559         } else {
4560                 return record_declaration(declaration, false);
4561         }
4562 }
4563
4564 static void parse_declaration(parsed_declaration_func finished_declaration)
4565 {
4566         declaration_specifiers_t specifiers;
4567         memset(&specifiers, 0, sizeof(specifiers));
4568         parse_declaration_specifiers(&specifiers);
4569
4570         if (token.type == ';') {
4571                 parse_anonymous_declaration_rest(&specifiers);
4572         } else {
4573                 declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
4574                 parse_declaration_rest(declaration, &specifiers, finished_declaration);
4575         }
4576 }
4577
4578 static type_t *get_default_promoted_type(type_t *orig_type)
4579 {
4580         type_t *result = orig_type;
4581
4582         type_t *type = skip_typeref(orig_type);
4583         if (is_type_integer(type)) {
4584                 result = promote_integer(type);
4585         } else if (type == type_float) {
4586                 result = type_double;
4587         }
4588
4589         return result;
4590 }
4591
4592 static void parse_kr_declaration_list(declaration_t *declaration)
4593 {
4594         type_t *type = skip_typeref(declaration->type);
4595         if (!is_type_function(type))
4596                 return;
4597
4598         if (!type->function.kr_style_parameters)
4599                 return;
4600
4601         /* push function parameters */
4602         int       top        = environment_top();
4603         scope_t  *last_scope = scope;
4604         set_scope(&declaration->scope);
4605
4606         declaration_t *parameter = declaration->scope.declarations;
4607         for ( ; parameter != NULL; parameter = parameter->next) {
4608                 assert(parameter->parent_scope == NULL);
4609                 parameter->parent_scope = scope;
4610                 environment_push(parameter);
4611         }
4612
4613         /* parse declaration list */
4614         while (is_declaration_specifier(&token, false)) {
4615                 parse_declaration(finished_kr_declaration);
4616         }
4617
4618         /* pop function parameters */
4619         assert(scope == &declaration->scope);
4620         set_scope(last_scope);
4621         environment_pop_to(top);
4622
4623         /* update function type */
4624         type_t *new_type = duplicate_type(type);
4625
4626         function_parameter_t *parameters     = NULL;
4627         function_parameter_t *last_parameter = NULL;
4628
4629         declaration_t *parameter_declaration = declaration->scope.declarations;
4630         for( ; parameter_declaration != NULL;
4631                         parameter_declaration = parameter_declaration->next) {
4632                 type_t *parameter_type = parameter_declaration->type;
4633                 if (parameter_type == NULL) {
4634                         if (strict_mode) {
4635                                 errorf(HERE, "no type specified for function parameter '%Y'",
4636                                        parameter_declaration->symbol);
4637                         } else {
4638                                 if (warning.implicit_int) {
4639                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
4640                                                 parameter_declaration->symbol);
4641                                 }
4642                                 parameter_type              = type_int;
4643                                 parameter_declaration->type = parameter_type;
4644                         }
4645                 }
4646
4647                 semantic_parameter(parameter_declaration);
4648                 parameter_type = parameter_declaration->type;
4649
4650                 /*
4651                  * we need the default promoted types for the function type
4652                  */
4653                 parameter_type = get_default_promoted_type(parameter_type);
4654
4655                 function_parameter_t *function_parameter
4656                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
4657                 memset(function_parameter, 0, sizeof(function_parameter[0]));
4658
4659                 function_parameter->type = parameter_type;
4660                 if (last_parameter != NULL) {
4661                         last_parameter->next = function_parameter;
4662                 } else {
4663                         parameters = function_parameter;
4664                 }
4665                 last_parameter = function_parameter;
4666         }
4667
4668         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
4669          * prototype */
4670         new_type->function.parameters             = parameters;
4671         new_type->function.unspecified_parameters = true;
4672
4673         type = typehash_insert(new_type);
4674         if (type != new_type) {
4675                 obstack_free(type_obst, new_type);
4676         }
4677
4678         declaration->type = type;
4679 }
4680
4681 static bool first_err = true;
4682
4683 /**
4684  * When called with first_err set, prints the name of the current function,
4685  * else does noting.
4686  */
4687 static void print_in_function(void)
4688 {
4689         if (first_err) {
4690                 first_err = false;
4691                 diagnosticf("%s: In function '%Y':\n",
4692                         current_function->source_position.input_name,
4693                         current_function->symbol);
4694         }
4695 }
4696
4697 /**
4698  * Check if all labels are defined in the current function.
4699  * Check if all labels are used in the current function.
4700  */
4701 static void check_labels(void)
4702 {
4703         for (const goto_statement_t *goto_statement = goto_first;
4704             goto_statement != NULL;
4705             goto_statement = goto_statement->next) {
4706                 declaration_t *label = goto_statement->label;
4707
4708                 label->used = true;
4709                 if (label->source_position.input_name == NULL) {
4710                         print_in_function();
4711                         errorf(&goto_statement->base.source_position,
4712                                "label '%Y' used but not defined", label->symbol);
4713                  }
4714         }
4715         goto_first = goto_last = NULL;
4716
4717         if (warning.unused_label) {
4718                 for (const label_statement_t *label_statement = label_first;
4719                          label_statement != NULL;
4720                          label_statement = label_statement->next) {
4721                         const declaration_t *label = label_statement->label;
4722
4723                         if (! label->used) {
4724                                 print_in_function();
4725                                 warningf(&label_statement->base.source_position,
4726                                         "label '%Y' defined but not used", label->symbol);
4727                         }
4728                 }
4729         }
4730         label_first = label_last = NULL;
4731 }
4732
4733 /**
4734  * Check declarations of current_function for unused entities.
4735  */
4736 static void check_declarations(void)
4737 {
4738         if (warning.unused_parameter) {
4739                 const scope_t *scope = &current_function->scope;
4740
4741                 if (is_sym_main(current_function->symbol)) {
4742                         /* do not issue unused warnings for main */
4743                         return;
4744                 }
4745                 const declaration_t *parameter = scope->declarations;
4746                 for (; parameter != NULL; parameter = parameter->next) {
4747                         if (! parameter->used) {
4748                                 print_in_function();
4749                                 warningf(&parameter->source_position,
4750                                          "unused parameter '%Y'", parameter->symbol);
4751                         }
4752                 }
4753         }
4754         if (warning.unused_variable) {
4755         }
4756 }
4757
4758 static int determine_truth(expression_t const* const cond)
4759 {
4760         return
4761                 !is_constant_expression(cond) ? 0 :
4762                 fold_constant(cond) != 0      ? 1 :
4763                 -1;
4764 }
4765
4766 static bool noreturn_candidate;
4767
4768 static void check_reachable(statement_t *const stmt)
4769 {
4770         if (stmt->base.reachable)
4771                 return;
4772         if (stmt->kind != STATEMENT_DO_WHILE)
4773                 stmt->base.reachable = true;
4774
4775         statement_t *last = stmt;
4776         statement_t *next;
4777         switch (stmt->kind) {
4778                 case STATEMENT_INVALID:
4779                 case STATEMENT_EMPTY:
4780                 case STATEMENT_DECLARATION:
4781                 case STATEMENT_ASM:
4782                         next = stmt->base.next;
4783                         break;
4784
4785                 case STATEMENT_COMPOUND:
4786                         next = stmt->compound.statements;
4787                         break;
4788
4789                 case STATEMENT_RETURN:
4790                         noreturn_candidate = false;
4791                         return;
4792
4793                 case STATEMENT_IF: {
4794                         if_statement_t const* const ifs = &stmt->ifs;
4795                         int            const        val = determine_truth(ifs->condition);
4796
4797                         if (val >= 0)
4798                                 check_reachable(ifs->true_statement);
4799
4800                         if (val > 0)
4801                                 return;
4802
4803                         if (ifs->false_statement != NULL) {
4804                                 check_reachable(ifs->false_statement);
4805                                 return;
4806                         }
4807
4808                         next = stmt->base.next;
4809                         break;
4810                 }
4811
4812                 case STATEMENT_SWITCH: {
4813                         switch_statement_t const *const switchs = &stmt->switchs;
4814                         expression_t       const *const expr    = switchs->expression;
4815
4816                         if (is_constant_expression(expr)) {
4817                                 long                    const val      = fold_constant(expr);
4818                                 case_label_statement_t *      defaults = NULL;
4819                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4820                                         if (i->expression == NULL) {
4821                                                 defaults = i;
4822                                                 continue;
4823                                         }
4824
4825                                         if (i->first_case <= val && val <= i->last_case) {
4826                                                 check_reachable((statement_t*)i);
4827                                                 return;
4828                                         }
4829                                 }
4830
4831                                 if (defaults != NULL) {
4832                                         check_reachable((statement_t*)defaults);
4833                                         return;
4834                                 }
4835                         } else {
4836                                 bool has_default = false;
4837                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4838                                         if (i->expression == NULL)
4839                                                 has_default = true;
4840
4841                                         check_reachable((statement_t*)i);
4842                                 }
4843
4844                                 if (has_default)
4845                                         return;
4846                         }
4847
4848                         next = stmt->base.next;
4849                         break;
4850                 }
4851
4852                 case STATEMENT_EXPRESSION: {
4853                         /* Check for noreturn function call */
4854                         expression_t const *const expr = stmt->expression.expression;
4855                         if (expr->kind == EXPR_CALL) {
4856                                 expression_t const *const func = expr->call.function;
4857                                 if (func->kind == EXPR_REFERENCE) {
4858                                         declaration_t const *const decl = func->reference.declaration;
4859                                         if (decl != NULL && decl->modifiers & DM_NORETURN) {
4860                                                 return;
4861                                         }
4862                                 }
4863                         }
4864
4865                         next = stmt->base.next;
4866                         break;
4867                 }
4868
4869                 case STATEMENT_CONTINUE: {
4870                         statement_t *parent = stmt;
4871                         for (;;) {
4872                                 parent = parent->base.parent;
4873                                 if (parent == NULL) /* continue not within loop */
4874                                         return;
4875
4876                                 next = parent;
4877                                 switch (parent->kind) {
4878                                         case STATEMENT_WHILE:    goto continue_while;
4879                                         case STATEMENT_DO_WHILE: goto continue_do_while;
4880                                         case STATEMENT_FOR:      goto continue_for;
4881
4882                                         default: break;
4883                                 }
4884                         }
4885                 }
4886
4887                 case STATEMENT_BREAK: {
4888                         statement_t *parent = stmt;
4889                         for (;;) {
4890                                 parent = parent->base.parent;
4891                                 if (parent == NULL) /* break not within loop/switch */
4892                                         return;
4893
4894                                 switch (parent->kind) {
4895                                         case STATEMENT_SWITCH:
4896                                         case STATEMENT_WHILE:
4897                                         case STATEMENT_DO_WHILE:
4898                                         case STATEMENT_FOR:
4899                                                 last = parent;
4900                                                 next = parent->base.next;
4901                                                 goto found_break_parent;
4902
4903                                         default: break;
4904                                 }
4905                         }
4906 found_break_parent:
4907                         break;
4908                 }
4909
4910                 case STATEMENT_GOTO:
4911                         next = stmt->gotos.label->init.statement;
4912                         if (next == NULL) /* missing label */
4913                                 return;
4914                         break;
4915
4916                 case STATEMENT_LABEL:
4917                         next = stmt->label.statement;
4918                         break;
4919
4920                 case STATEMENT_CASE_LABEL:
4921                         next = stmt->case_label.statement;
4922                         break;
4923
4924                 case STATEMENT_WHILE: {
4925                         while_statement_t const *const whiles = &stmt->whiles;
4926                         int                      const val    = determine_truth(whiles->condition);
4927
4928                         if (val >= 0)
4929                                 check_reachable(whiles->body);
4930
4931                         if (val > 0)
4932                                 return;
4933
4934                         next = stmt->base.next;
4935                         break;
4936                 }
4937
4938                 case STATEMENT_DO_WHILE:
4939                         next = stmt->do_while.body;
4940                         break;
4941
4942                 case STATEMENT_FOR: {
4943                         for_statement_t *const fors = &stmt->fors;
4944
4945                         if (fors->condition_reachable)
4946                                 return;
4947                         fors->condition_reachable = true;
4948
4949                         expression_t const *const cond = fors->condition;
4950                         int          const        val  =
4951                                 cond == NULL ? 1 : determine_truth(cond);
4952
4953                         if (val >= 0)
4954                                 check_reachable(fors->body);
4955
4956                         if (val > 0)
4957                                 return;
4958
4959                         next = stmt->base.next;
4960                         break;
4961                 }
4962
4963                 case STATEMENT_MS_TRY: {
4964                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
4965                         check_reachable(ms_try->try_statement);
4966                         next = ms_try->final_statement;
4967                         break;
4968                 }
4969
4970                 case STATEMENT_LEAVE: {
4971                         statement_t *parent = stmt;
4972                         for (;;) {
4973                                 parent = parent->base.parent;
4974                                 if (parent == NULL) /* __leave not within __try */
4975                                         return;
4976
4977                                 if (parent->kind == STATEMENT_MS_TRY) {
4978                                         last = parent;
4979                                         next = parent->ms_try.final_statement;
4980                                         break;
4981                                 }
4982                         }
4983                         break;
4984                 }
4985         }
4986
4987         while (next == NULL) {
4988                 next = last->base.parent;
4989                 if (next == NULL) {
4990                         noreturn_candidate = false;
4991
4992                         type_t *const type = current_function->type;
4993                         assert(is_type_function(type));
4994                         type_t *const ret  = skip_typeref(type->function.return_type);
4995                         if (warning.return_type                    &&
4996                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
4997                             is_type_valid(ret)                     &&
4998                             !is_sym_main(current_function->symbol)) {
4999                                 warningf(&stmt->base.source_position,
5000                                          "control reaches end of non-void function");
5001                         }
5002                         return;
5003                 }
5004
5005                 switch (next->kind) {
5006                         case STATEMENT_INVALID:
5007                         case STATEMENT_EMPTY:
5008                         case STATEMENT_DECLARATION:
5009                         case STATEMENT_EXPRESSION:
5010                         case STATEMENT_ASM:
5011                         case STATEMENT_RETURN:
5012                         case STATEMENT_CONTINUE:
5013                         case STATEMENT_BREAK:
5014                         case STATEMENT_GOTO:
5015                         case STATEMENT_LEAVE:
5016                                 panic("invalid control flow in function");
5017
5018                         case STATEMENT_COMPOUND:
5019                         case STATEMENT_IF:
5020                         case STATEMENT_SWITCH:
5021                         case STATEMENT_LABEL:
5022                         case STATEMENT_CASE_LABEL:
5023                                 last = next;
5024                                 next = next->base.next;
5025                                 break;
5026
5027                         case STATEMENT_WHILE: {
5028 continue_while:
5029                                 if (next->base.reachable)
5030                                         return;
5031                                 next->base.reachable = true;
5032
5033                                 while_statement_t const *const whiles = &next->whiles;
5034                                 int                      const val    = determine_truth(whiles->condition);
5035
5036                                 if (val >= 0)
5037                                         check_reachable(whiles->body);
5038
5039                                 if (val > 0)
5040                                         return;
5041
5042                                 last = next;
5043                                 next = next->base.next;
5044                                 break;
5045                         }
5046
5047                         case STATEMENT_DO_WHILE: {
5048 continue_do_while:
5049                                 if (next->base.reachable)
5050                                         return;
5051                                 next->base.reachable = true;
5052
5053                                 do_while_statement_t const *const dw  = &next->do_while;
5054                                 int                  const        val = determine_truth(dw->condition);
5055
5056                                 if (val >= 0)
5057                                         check_reachable(dw->body);
5058
5059                                 if (val > 0)
5060                                         return;
5061
5062                                 last = next;
5063                                 next = next->base.next;
5064                                 break;
5065                         }
5066
5067                         case STATEMENT_FOR: {
5068 continue_for:;
5069                                 for_statement_t *const fors = &next->fors;
5070
5071                                 fors->step_reachable = true;
5072
5073                                 if (fors->condition_reachable)
5074                                         return;
5075                                 fors->condition_reachable = true;
5076
5077                                 expression_t const *const cond = fors->condition;
5078                                 int          const        val  =
5079                                         cond == NULL ? 1 : determine_truth(cond);
5080
5081                                 if (val >= 0)
5082                                         check_reachable(fors->body);
5083
5084                                 if (val > 0)
5085                                         return;
5086
5087                                 last = next;
5088                                 next = next->base.next;
5089                                 break;
5090                         }
5091
5092                         case STATEMENT_MS_TRY:
5093                                 last = next;
5094                                 next = next->ms_try.final_statement;
5095                                 break;
5096                 }
5097         }
5098
5099         if (next == NULL) {
5100                 next = stmt->base.parent;
5101                 if (next == NULL) {
5102                         warningf(&stmt->base.source_position,
5103                                  "control reaches end of non-void function");
5104                 }
5105         }
5106
5107         check_reachable(next);
5108 }
5109
5110 static void check_unreachable(statement_t const* const stmt)
5111 {
5112         if (!stmt->base.reachable            &&
5113             stmt->kind != STATEMENT_DO_WHILE &&
5114             stmt->kind != STATEMENT_FOR      &&
5115             (stmt->kind != STATEMENT_COMPOUND || stmt->compound.statements == NULL)) {
5116                 warningf(&stmt->base.source_position, "statement is unreachable");
5117         }
5118
5119         switch (stmt->kind) {
5120                 case STATEMENT_INVALID:
5121                 case STATEMENT_EMPTY:
5122                 case STATEMENT_RETURN:
5123                 case STATEMENT_DECLARATION:
5124                 case STATEMENT_EXPRESSION:
5125                 case STATEMENT_CONTINUE:
5126                 case STATEMENT_BREAK:
5127                 case STATEMENT_GOTO:
5128                 case STATEMENT_ASM:
5129                 case STATEMENT_LEAVE:
5130                         break;
5131
5132                 case STATEMENT_COMPOUND:
5133                         if (stmt->compound.statements)
5134                                 check_unreachable(stmt->compound.statements);
5135                         break;
5136
5137                 case STATEMENT_IF:
5138                         check_unreachable(stmt->ifs.true_statement);
5139                         if (stmt->ifs.false_statement != NULL)
5140                                 check_unreachable(stmt->ifs.false_statement);
5141                         break;
5142
5143                 case STATEMENT_SWITCH:
5144                         check_unreachable(stmt->switchs.body);
5145                         break;
5146
5147                 case STATEMENT_LABEL:
5148                         check_unreachable(stmt->label.statement);
5149                         break;
5150
5151                 case STATEMENT_CASE_LABEL:
5152                         check_unreachable(stmt->case_label.statement);
5153                         break;
5154
5155                 case STATEMENT_WHILE:
5156                         check_unreachable(stmt->whiles.body);
5157                         break;
5158
5159                 case STATEMENT_DO_WHILE:
5160                         check_unreachable(stmt->do_while.body);
5161                         if (!stmt->base.reachable) {
5162                                 expression_t const *const cond = stmt->do_while.condition;
5163                                 if (determine_truth(cond) >= 0) {
5164                                         warningf(&cond->base.source_position,
5165                                                  "condition of do-while-loop is unreachable");
5166                                 }
5167                         }
5168                         break;
5169
5170                 case STATEMENT_FOR: {
5171                         for_statement_t const* const fors = &stmt->fors;
5172
5173                         // if init and step are unreachable, cond is unreachable, too
5174                         if (!stmt->base.reachable && !fors->step_reachable) {
5175                                 warningf(&stmt->base.source_position, "statement is unreachable");
5176                         } else {
5177                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
5178                                         warningf(&fors->initialisation->base.source_position,
5179                                                  "initialisation of for-statement is unreachable");
5180                                 }
5181
5182                                 if (!fors->condition_reachable && fors->condition != NULL) {
5183                                         warningf(&fors->condition->base.source_position,
5184                                                  "condition of for-statement is unreachable");
5185                                 }
5186
5187                                 if (!fors->step_reachable && fors->step != NULL) {
5188                                         warningf(&fors->step->base.source_position,
5189                                                  "step of for-statement is unreachable");
5190                                 }
5191                         }
5192
5193                         check_unreachable(fors->body);
5194                         break;
5195                 }
5196
5197                 case STATEMENT_MS_TRY: {
5198                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
5199                         check_unreachable(ms_try->try_statement);
5200                         check_unreachable(ms_try->final_statement);
5201                 }
5202         }
5203
5204         if (stmt->base.next)
5205                 check_unreachable(stmt->base.next);
5206 }
5207
5208 static void parse_external_declaration(void)
5209 {
5210         /* function-definitions and declarations both start with declaration
5211          * specifiers */
5212         declaration_specifiers_t specifiers;
5213         memset(&specifiers, 0, sizeof(specifiers));
5214
5215         add_anchor_token(';');
5216         parse_declaration_specifiers(&specifiers);
5217         rem_anchor_token(';');
5218
5219         /* must be a declaration */
5220         if (token.type == ';') {
5221                 parse_anonymous_declaration_rest(&specifiers);
5222                 return;
5223         }
5224
5225         add_anchor_token(',');
5226         add_anchor_token('=');
5227         rem_anchor_token(';');
5228
5229         /* declarator is common to both function-definitions and declarations */
5230         declaration_t *ndeclaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
5231
5232         rem_anchor_token(',');
5233         rem_anchor_token('=');
5234         rem_anchor_token(';');
5235
5236         /* must be a declaration */
5237         switch (token.type) {
5238                 case ',':
5239                 case ';':
5240                 case '=':
5241                         parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
5242                         return;
5243         }
5244
5245         /* must be a function definition */
5246         parse_kr_declaration_list(ndeclaration);
5247
5248         if (token.type != '{') {
5249                 parse_error_expected("while parsing function definition", '{', NULL);
5250                 eat_until_matching_token(';');
5251                 return;
5252         }
5253
5254         type_t *type = ndeclaration->type;
5255
5256         /* note that we don't skip typerefs: the standard doesn't allow them here
5257          * (so we can't use is_type_function here) */
5258         if (type->kind != TYPE_FUNCTION) {
5259                 if (is_type_valid(type)) {
5260                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5261                                type, ndeclaration->symbol);
5262                 }
5263                 eat_block();
5264                 return;
5265         }
5266
5267         if (warning.aggregate_return &&
5268             is_type_compound(skip_typeref(type->function.return_type))) {
5269                 warningf(HERE, "function '%Y' returns an aggregate",
5270                          ndeclaration->symbol);
5271         }
5272         if (warning.traditional && !type->function.unspecified_parameters) {
5273                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
5274                         ndeclaration->symbol);
5275         }
5276         if (warning.old_style_definition && type->function.unspecified_parameters) {
5277                 warningf(HERE, "old-style function definition '%Y'",
5278                         ndeclaration->symbol);
5279         }
5280
5281         /* § 6.7.5.3 (14) a function definition with () means no
5282          * parameters (and not unspecified parameters) */
5283         if (type->function.unspecified_parameters
5284                         && type->function.parameters == NULL
5285                         && !type->function.kr_style_parameters) {
5286                 type_t *duplicate = duplicate_type(type);
5287                 duplicate->function.unspecified_parameters = false;
5288
5289                 type = typehash_insert(duplicate);
5290                 if (type != duplicate) {
5291                         obstack_free(type_obst, duplicate);
5292                 }
5293                 ndeclaration->type = type;
5294         }
5295
5296         declaration_t *const declaration = record_declaration(ndeclaration, true);
5297         if (ndeclaration != declaration) {
5298                 declaration->scope = ndeclaration->scope;
5299         }
5300         type = skip_typeref(declaration->type);
5301
5302         /* push function parameters and switch scope */
5303         int       top        = environment_top();
5304         scope_t  *last_scope = scope;
5305         set_scope(&declaration->scope);
5306
5307         declaration_t *parameter = declaration->scope.declarations;
5308         for( ; parameter != NULL; parameter = parameter->next) {
5309                 if (parameter->parent_scope == &ndeclaration->scope) {
5310                         parameter->parent_scope = scope;
5311                 }
5312                 assert(parameter->parent_scope == NULL
5313                                 || parameter->parent_scope == scope);
5314                 parameter->parent_scope = scope;
5315                 if (parameter->symbol == NULL) {
5316                         errorf(&parameter->source_position, "parameter name omitted");
5317                         continue;
5318                 }
5319                 environment_push(parameter);
5320         }
5321
5322         if (declaration->init.statement != NULL) {
5323                 parser_error_multiple_definition(declaration, HERE);
5324                 eat_block();
5325         } else {
5326                 /* parse function body */
5327                 int            label_stack_top      = label_top();
5328                 declaration_t *old_current_function = current_function;
5329                 current_function                    = declaration;
5330                 current_parent                      = NULL;
5331
5332                 statement_t *const body = parse_compound_statement(false);
5333                 declaration->init.statement = body;
5334                 first_err = true;
5335                 check_labels();
5336                 check_declarations();
5337                 if (warning.return_type      ||
5338                     warning.unreachable_code ||
5339                     (warning.missing_noreturn && !(declaration->modifiers & DM_NORETURN))) {
5340                         noreturn_candidate = true;
5341                         check_reachable(body);
5342                         if (warning.unreachable_code)
5343                                 check_unreachable(body);
5344                         if (warning.missing_noreturn &&
5345                             noreturn_candidate       &&
5346                             !(declaration->modifiers & DM_NORETURN)) {
5347                                 warningf(&body->base.source_position,
5348                                          "function '%#T' is candidate for attribute 'noreturn'",
5349                                          type, declaration->symbol);
5350                         }
5351                 }
5352
5353                 assert(current_parent   == NULL);
5354                 assert(current_function == declaration);
5355                 current_function = old_current_function;
5356                 label_pop_to(label_stack_top);
5357         }
5358
5359         assert(scope == &declaration->scope);
5360         set_scope(last_scope);
5361         environment_pop_to(top);
5362 }
5363
5364 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5365                                   source_position_t *source_position)
5366 {
5367         type_t *type = allocate_type_zero(TYPE_BITFIELD, source_position);
5368
5369         type->bitfield.base_type = base_type;
5370         type->bitfield.size      = size;
5371
5372         return type;
5373 }
5374
5375 static declaration_t *find_compound_entry(declaration_t *compound_declaration,
5376                                           symbol_t *symbol)
5377 {
5378         declaration_t *iter = compound_declaration->scope.declarations;
5379         for( ; iter != NULL; iter = iter->next) {
5380                 if (iter->namespc != NAMESPACE_NORMAL)
5381                         continue;
5382
5383                 if (iter->symbol == NULL) {
5384                         type_t *type = skip_typeref(iter->type);
5385                         if (is_type_compound(type)) {
5386                                 declaration_t *result
5387                                         = find_compound_entry(type->compound.declaration, symbol);
5388                                 if (result != NULL)
5389                                         return result;
5390                         }
5391                         continue;
5392                 }
5393
5394                 if (iter->symbol == symbol) {
5395                         return iter;
5396                 }
5397         }
5398
5399         return NULL;
5400 }
5401
5402 static void parse_compound_declarators(declaration_t *struct_declaration,
5403                 const declaration_specifiers_t *specifiers)
5404 {
5405         declaration_t *last_declaration = struct_declaration->scope.declarations;
5406         if (last_declaration != NULL) {
5407                 while(last_declaration->next != NULL) {
5408                         last_declaration = last_declaration->next;
5409                 }
5410         }
5411
5412         while(1) {
5413                 declaration_t *declaration;
5414
5415                 if (token.type == ':') {
5416                         source_position_t source_position = *HERE;
5417                         next_token();
5418
5419                         type_t *base_type = specifiers->type;
5420                         expression_t *size = parse_constant_expression();
5421
5422                         if (!is_type_integer(skip_typeref(base_type))) {
5423                                 errorf(HERE, "bitfield base type '%T' is not an integer type",
5424                                        base_type);
5425                         }
5426
5427                         type_t *type = make_bitfield_type(base_type, size, &source_position);
5428
5429                         declaration                         = allocate_declaration_zero();
5430                         declaration->namespc                = NAMESPACE_NORMAL;
5431                         declaration->declared_storage_class = STORAGE_CLASS_NONE;
5432                         declaration->storage_class          = STORAGE_CLASS_NONE;
5433                         declaration->source_position        = source_position;
5434                         declaration->modifiers              = specifiers->modifiers;
5435                         declaration->type                   = type;
5436                 } else {
5437                         declaration = parse_declarator(specifiers,/*may_be_abstract=*/true);
5438
5439                         type_t *orig_type = declaration->type;
5440                         type_t *type      = skip_typeref(orig_type);
5441
5442                         if (token.type == ':') {
5443                                 source_position_t source_position = *HERE;
5444                                 next_token();
5445                                 expression_t *size = parse_constant_expression();
5446
5447                                 if (!is_type_integer(type)) {
5448                                         errorf(HERE, "bitfield base type '%T' is not an integer type",
5449                                                orig_type);
5450                                 }
5451
5452                                 type_t *bitfield_type = make_bitfield_type(orig_type, size, &source_position);
5453                                 declaration->type = bitfield_type;
5454                         } else {
5455                                 /* TODO we ignore arrays for now... what is missing is a check
5456                                  * that they're at the end of the struct */
5457                                 if (is_type_incomplete(type) && !is_type_array(type)) {
5458                                         errorf(HERE,
5459                                                "compound member '%Y' has incomplete type '%T'",
5460                                                declaration->symbol, orig_type);
5461                                 } else if (is_type_function(type)) {
5462                                         errorf(HERE, "compound member '%Y' must not have function type '%T'",
5463                                                declaration->symbol, orig_type);
5464                                 }
5465                         }
5466                 }
5467
5468                 /* make sure we don't define a symbol multiple times */
5469                 symbol_t *symbol = declaration->symbol;
5470                 if (symbol != NULL) {
5471                         declaration_t *prev_decl
5472                                 = find_compound_entry(struct_declaration, symbol);
5473
5474                         if (prev_decl != NULL) {
5475                                 assert(prev_decl->symbol == symbol);
5476                                 errorf(&declaration->source_position,
5477                                        "multiple declarations of symbol '%Y' (declared %P)",
5478                                        symbol, &prev_decl->source_position);
5479                         }
5480                 }
5481
5482                 /* append declaration */
5483                 if (last_declaration != NULL) {
5484                         last_declaration->next = declaration;
5485                 } else {
5486                         struct_declaration->scope.declarations = declaration;
5487                 }
5488                 last_declaration = declaration;
5489
5490                 if (token.type != ',')
5491                         break;
5492                 next_token();
5493         }
5494         expect(';');
5495
5496 end_error:
5497         ;
5498 }
5499
5500 static void parse_compound_type_entries(declaration_t *compound_declaration)
5501 {
5502         eat('{');
5503         add_anchor_token('}');
5504
5505         while(token.type != '}' && token.type != T_EOF) {
5506                 declaration_specifiers_t specifiers;
5507                 memset(&specifiers, 0, sizeof(specifiers));
5508                 parse_declaration_specifiers(&specifiers);
5509
5510                 parse_compound_declarators(compound_declaration, &specifiers);
5511         }
5512         rem_anchor_token('}');
5513
5514         if (token.type == T_EOF) {
5515                 errorf(HERE, "EOF while parsing struct");
5516         }
5517         next_token();
5518 }
5519
5520 static type_t *parse_typename(void)
5521 {
5522         declaration_specifiers_t specifiers;
5523         memset(&specifiers, 0, sizeof(specifiers));
5524         parse_declaration_specifiers(&specifiers);
5525         if (specifiers.declared_storage_class != STORAGE_CLASS_NONE) {
5526                 /* TODO: improve error message, user does probably not know what a
5527                  * storage class is...
5528                  */
5529                 errorf(HERE, "typename may not have a storage class");
5530         }
5531
5532         type_t *result = parse_abstract_declarator(specifiers.type);
5533
5534         return result;
5535 }
5536
5537
5538
5539
5540 typedef expression_t* (*parse_expression_function) (unsigned precedence);
5541 typedef expression_t* (*parse_expression_infix_function) (unsigned precedence,
5542                                                           expression_t *left);
5543
5544 typedef struct expression_parser_function_t expression_parser_function_t;
5545 struct expression_parser_function_t {
5546         unsigned                         precedence;
5547         parse_expression_function        parser;
5548         unsigned                         infix_precedence;
5549         parse_expression_infix_function  infix_parser;
5550 };
5551
5552 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
5553
5554 /**
5555  * Prints an error message if an expression was expected but not read
5556  */
5557 static expression_t *expected_expression_error(void)
5558 {
5559         /* skip the error message if the error token was read */
5560         if (token.type != T_ERROR) {
5561                 errorf(HERE, "expected expression, got token '%K'", &token);
5562         }
5563         next_token();
5564
5565         return create_invalid_expression();
5566 }
5567
5568 /**
5569  * Parse a string constant.
5570  */
5571 static expression_t *parse_string_const(void)
5572 {
5573         wide_string_t wres;
5574         if (token.type == T_STRING_LITERAL) {
5575                 string_t res = token.v.string;
5576                 next_token();
5577                 while (token.type == T_STRING_LITERAL) {
5578                         res = concat_strings(&res, &token.v.string);
5579                         next_token();
5580                 }
5581                 if (token.type != T_WIDE_STRING_LITERAL) {
5582                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
5583                         /* note: that we use type_char_ptr here, which is already the
5584                          * automatic converted type. revert_automatic_type_conversion
5585                          * will construct the array type */
5586                         cnst->base.type    = warning.write_strings ? type_const_char_ptr : type_char_ptr;
5587                         cnst->string.value = res;
5588                         return cnst;
5589                 }
5590
5591                 wres = concat_string_wide_string(&res, &token.v.wide_string);
5592         } else {
5593                 wres = token.v.wide_string;
5594         }
5595         next_token();
5596
5597         for (;;) {
5598                 switch (token.type) {
5599                         case T_WIDE_STRING_LITERAL:
5600                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
5601                                 break;
5602
5603                         case T_STRING_LITERAL:
5604                                 wres = concat_wide_string_string(&wres, &token.v.string);
5605                                 break;
5606
5607                         default: {
5608                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
5609                                 cnst->base.type         = warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
5610                                 cnst->wide_string.value = wres;
5611                                 return cnst;
5612                         }
5613                 }
5614                 next_token();
5615         }
5616 }
5617
5618 /**
5619  * Parse an integer constant.
5620  */
5621 static expression_t *parse_int_const(void)
5622 {
5623         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5624         cnst->base.source_position = *HERE;
5625         cnst->base.type            = token.datatype;
5626         cnst->conste.v.int_value   = token.v.intvalue;
5627
5628         next_token();
5629
5630         return cnst;
5631 }
5632
5633 /**
5634  * Parse a character constant.
5635  */
5636 static expression_t *parse_character_constant(void)
5637 {
5638         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
5639
5640         cnst->base.source_position = *HERE;
5641         cnst->base.type            = token.datatype;
5642         cnst->conste.v.character   = token.v.string;
5643
5644         if (cnst->conste.v.character.size != 1) {
5645                 if (warning.multichar && (c_mode & _GNUC)) {
5646                         /* TODO */
5647                         warningf(HERE, "multi-character character constant");
5648                 } else {
5649                         errorf(HERE, "more than 1 characters in character constant");
5650                 }
5651         }
5652         next_token();
5653
5654         return cnst;
5655 }
5656
5657 /**
5658  * Parse a wide character constant.
5659  */
5660 static expression_t *parse_wide_character_constant(void)
5661 {
5662         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
5663
5664         cnst->base.source_position    = *HERE;
5665         cnst->base.type               = token.datatype;
5666         cnst->conste.v.wide_character = token.v.wide_string;
5667
5668         if (cnst->conste.v.wide_character.size != 1) {
5669                 if (warning.multichar && (c_mode & _GNUC)) {
5670                         /* TODO */
5671                         warningf(HERE, "multi-character character constant");
5672                 } else {
5673                         errorf(HERE, "more than 1 characters in character constant");
5674                 }
5675         }
5676         next_token();
5677
5678         return cnst;
5679 }
5680
5681 /**
5682  * Parse a float constant.
5683  */
5684 static expression_t *parse_float_const(void)
5685 {
5686         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5687         cnst->base.type            = token.datatype;
5688         cnst->conste.v.float_value = token.v.floatvalue;
5689
5690         next_token();
5691
5692         return cnst;
5693 }
5694
5695 static declaration_t *create_implicit_function(symbol_t *symbol,
5696                 const source_position_t *source_position)
5697 {
5698         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION, source_position);
5699         ntype->function.return_type            = type_int;
5700         ntype->function.unspecified_parameters = true;
5701
5702         type_t *type = typehash_insert(ntype);
5703         if (type != ntype) {
5704                 free_type(ntype);
5705         }
5706
5707         declaration_t *const declaration    = allocate_declaration_zero();
5708         declaration->storage_class          = STORAGE_CLASS_EXTERN;
5709         declaration->declared_storage_class = STORAGE_CLASS_EXTERN;
5710         declaration->type                   = type;
5711         declaration->symbol                 = symbol;
5712         declaration->source_position        = *source_position;
5713         declaration->implicit               = true;
5714
5715         bool strict_prototypes_old = warning.strict_prototypes;
5716         warning.strict_prototypes  = false;
5717         record_declaration(declaration, false);
5718         warning.strict_prototypes = strict_prototypes_old;
5719
5720         return declaration;
5721 }
5722
5723 /**
5724  * Creates a return_type (func)(argument_type) function type if not
5725  * already exists.
5726  */
5727 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
5728                                     type_t *argument_type2)
5729 {
5730         function_parameter_t *parameter2
5731                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
5732         memset(parameter2, 0, sizeof(parameter2[0]));
5733         parameter2->type = argument_type2;
5734
5735         function_parameter_t *parameter1
5736                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
5737         memset(parameter1, 0, sizeof(parameter1[0]));
5738         parameter1->type = argument_type1;
5739         parameter1->next = parameter2;
5740
5741         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5742         type->function.return_type = return_type;
5743         type->function.parameters  = parameter1;
5744
5745         type_t *result = typehash_insert(type);
5746         if (result != type) {
5747                 free_type(type);
5748         }
5749
5750         return result;
5751 }
5752
5753 /**
5754  * Creates a return_type (func)(argument_type) function type if not
5755  * already exists.
5756  *
5757  * @param return_type    the return type
5758  * @param argument_type  the argument type
5759  */
5760 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
5761 {
5762         function_parameter_t *parameter
5763                 = obstack_alloc(type_obst, sizeof(parameter[0]));
5764         memset(parameter, 0, sizeof(parameter[0]));
5765         parameter->type = argument_type;
5766
5767         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5768         type->function.return_type = return_type;
5769         type->function.parameters  = parameter;
5770
5771         type_t *result = typehash_insert(type);
5772         if (result != type) {
5773                 free_type(type);
5774         }
5775
5776         return result;
5777 }
5778
5779 static type_t *make_function_0_type(type_t *return_type)
5780 {
5781         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5782         type->function.return_type = return_type;
5783         type->function.parameters  = NULL;
5784
5785         type_t *result = typehash_insert(type);
5786         if (result != type) {
5787                 free_type(type);
5788         }
5789
5790         return result;
5791 }
5792
5793 /**
5794  * Creates a function type for some function like builtins.
5795  *
5796  * @param symbol   the symbol describing the builtin
5797  */
5798 static type_t *get_builtin_symbol_type(symbol_t *symbol)
5799 {
5800         switch(symbol->ID) {
5801         case T___builtin_alloca:
5802                 return make_function_1_type(type_void_ptr, type_size_t);
5803         case T___builtin_huge_val:
5804                 return make_function_0_type(type_double);
5805         case T___builtin_nan:
5806                 return make_function_1_type(type_double, type_char_ptr);
5807         case T___builtin_nanf:
5808                 return make_function_1_type(type_float, type_char_ptr);
5809         case T___builtin_nand:
5810                 return make_function_1_type(type_long_double, type_char_ptr);
5811         case T___builtin_va_end:
5812                 return make_function_1_type(type_void, type_valist);
5813         case T___builtin_expect:
5814                 return make_function_2_type(type_long, type_long, type_long);
5815         default:
5816                 internal_errorf(HERE, "not implemented builtin symbol found");
5817         }
5818 }
5819
5820 /**
5821  * Performs automatic type cast as described in § 6.3.2.1.
5822  *
5823  * @param orig_type  the original type
5824  */
5825 static type_t *automatic_type_conversion(type_t *orig_type)
5826 {
5827         type_t *type = skip_typeref(orig_type);
5828         if (is_type_array(type)) {
5829                 array_type_t *array_type   = &type->array;
5830                 type_t       *element_type = array_type->element_type;
5831                 unsigned      qualifiers   = array_type->base.qualifiers;
5832
5833                 return make_pointer_type(element_type, qualifiers);
5834         }
5835
5836         if (is_type_function(type)) {
5837                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
5838         }
5839
5840         return orig_type;
5841 }
5842
5843 /**
5844  * reverts the automatic casts of array to pointer types and function
5845  * to function-pointer types as defined § 6.3.2.1
5846  */
5847 type_t *revert_automatic_type_conversion(const expression_t *expression)
5848 {
5849         switch (expression->kind) {
5850                 case EXPR_REFERENCE: return expression->reference.declaration->type;
5851                 case EXPR_SELECT:    return expression->select.compound_entry->type;
5852
5853                 case EXPR_UNARY_DEREFERENCE: {
5854                         const expression_t *const value = expression->unary.value;
5855                         type_t             *const type  = skip_typeref(value->base.type);
5856                         assert(is_type_pointer(type));
5857                         return type->pointer.points_to;
5858                 }
5859
5860                 case EXPR_BUILTIN_SYMBOL:
5861                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
5862
5863                 case EXPR_ARRAY_ACCESS: {
5864                         const expression_t *array_ref = expression->array_access.array_ref;
5865                         type_t             *type_left = skip_typeref(array_ref->base.type);
5866                         if (!is_type_valid(type_left))
5867                                 return type_left;
5868                         assert(is_type_pointer(type_left));
5869                         return type_left->pointer.points_to;
5870                 }
5871
5872                 case EXPR_STRING_LITERAL: {
5873                         size_t size = expression->string.value.size;
5874                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
5875                 }
5876
5877                 case EXPR_WIDE_STRING_LITERAL: {
5878                         size_t size = expression->wide_string.value.size;
5879                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
5880                 }
5881
5882                 case EXPR_COMPOUND_LITERAL:
5883                         return expression->compound_literal.type;
5884
5885                 default: break;
5886         }
5887
5888         return expression->base.type;
5889 }
5890
5891 static expression_t *parse_reference(void)
5892 {
5893         expression_t *expression = allocate_expression_zero(EXPR_REFERENCE);
5894
5895         reference_expression_t *ref = &expression->reference;
5896         symbol_t *const symbol = token.v.symbol;
5897
5898         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
5899
5900         source_position_t source_position = token.source_position;
5901         next_token();
5902
5903         if (declaration == NULL) {
5904                 if (token.type == '(') {
5905                         /* an implicitly declared function */
5906                         if (strict_mode) {
5907                                 errorf(HERE, "unknown symbol '%Y' found.", symbol);
5908                         } else if (warning.implicit_function_declaration) {
5909                                 warningf(HERE, "implicit declaration of function '%Y'",
5910                                         symbol);
5911                         }
5912
5913                         declaration = create_implicit_function(symbol,
5914                                                                &source_position);
5915                 } else {
5916                         errorf(HERE, "unknown symbol '%Y' found.", symbol);
5917                         declaration = create_error_declaration(symbol, STORAGE_CLASS_NONE);
5918                 }
5919         }
5920
5921         type_t *type = declaration->type;
5922
5923         /* we always do the auto-type conversions; the & and sizeof parser contains
5924          * code to revert this! */
5925         type = automatic_type_conversion(type);
5926
5927         ref->declaration = declaration;
5928         ref->base.type   = type;
5929
5930         /* this declaration is used */
5931         declaration->used = true;
5932
5933         /* check for deprecated functions */
5934         if (warning.deprecated_declarations &&
5935             declaration->modifiers & DM_DEPRECATED) {
5936                 char const *const prefix = is_type_function(declaration->type) ?
5937                         "function" : "variable";
5938
5939                 if (declaration->deprecated_string != NULL) {
5940                         warningf(&source_position,
5941                                 "%s '%Y' is deprecated (declared %P): \"%s\"", prefix,
5942                                 declaration->symbol, &declaration->source_position,
5943                                 declaration->deprecated_string);
5944                 } else {
5945                         warningf(&source_position,
5946                                 "%s '%Y' is deprecated (declared %P)", prefix,
5947                                 declaration->symbol, &declaration->source_position);
5948                 }
5949         }
5950         if (warning.init_self && declaration == current_init_decl) {
5951                 current_init_decl = NULL;
5952                 warningf(&source_position,
5953                         "variable '%#T' is initialized by itself",
5954                         declaration->type, declaration->symbol);
5955         }
5956
5957         return expression;
5958 }
5959
5960 static bool semantic_cast(expression_t *cast)
5961 {
5962         expression_t            *expression      = cast->unary.value;
5963         type_t                  *orig_dest_type  = cast->base.type;
5964         type_t                  *orig_type_right = expression->base.type;
5965         type_t            const *dst_type        = skip_typeref(orig_dest_type);
5966         type_t            const *src_type        = skip_typeref(orig_type_right);
5967         source_position_t const *pos             = &cast->base.source_position;
5968
5969         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
5970         if (dst_type == type_void)
5971                 return true;
5972
5973         /* only integer and pointer can be casted to pointer */
5974         if (is_type_pointer(dst_type)  &&
5975             !is_type_pointer(src_type) &&
5976             !is_type_integer(src_type) &&
5977             is_type_valid(src_type)) {
5978                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
5979                 return false;
5980         }
5981
5982         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
5983                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
5984                 return false;
5985         }
5986
5987         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
5988                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
5989                 return false;
5990         }
5991
5992         if (warning.cast_qual &&
5993             is_type_pointer(src_type) &&
5994             is_type_pointer(dst_type)) {
5995                 type_t *src = skip_typeref(src_type->pointer.points_to);
5996                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
5997                 unsigned missing_qualifiers =
5998                         src->base.qualifiers & ~dst->base.qualifiers;
5999                 if (missing_qualifiers != 0) {
6000                         warningf(pos,
6001                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
6002                                  missing_qualifiers, orig_type_right);
6003                 }
6004         }
6005         return true;
6006 }
6007
6008 static expression_t *parse_compound_literal(type_t *type)
6009 {
6010         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
6011
6012         parse_initializer_env_t env;
6013         env.type             = type;
6014         env.declaration      = NULL;
6015         env.must_be_constant = false;
6016         initializer_t *initializer = parse_initializer(&env);
6017         type = env.type;
6018
6019         expression->compound_literal.initializer = initializer;
6020         expression->compound_literal.type        = type;
6021         expression->base.type                    = automatic_type_conversion(type);
6022
6023         return expression;
6024 }
6025
6026 /**
6027  * Parse a cast expression.
6028  */
6029 static expression_t *parse_cast(void)
6030 {
6031         source_position_t source_position = token.source_position;
6032
6033         type_t *type  = parse_typename();
6034
6035         /* matching add_anchor_token() is at call site */
6036         rem_anchor_token(')');
6037         expect(')');
6038
6039         if (token.type == '{') {
6040                 return parse_compound_literal(type);
6041         }
6042
6043         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
6044         cast->base.source_position = source_position;
6045
6046         expression_t *value = parse_sub_expression(20);
6047         cast->base.type   = type;
6048         cast->unary.value = value;
6049
6050         if (! semantic_cast(cast)) {
6051                 /* TODO: record the error in the AST. else it is impossible to detect it */
6052         }
6053
6054         return cast;
6055 end_error:
6056         return create_invalid_expression();
6057 }
6058
6059 /**
6060  * Parse a statement expression.
6061  */
6062 static expression_t *parse_statement_expression(void)
6063 {
6064         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
6065
6066         statement_t *statement           = parse_compound_statement(true);
6067         expression->statement.statement  = statement;
6068         expression->base.source_position = statement->base.source_position;
6069
6070         /* find last statement and use its type */
6071         type_t *type = type_void;
6072         const statement_t *stmt = statement->compound.statements;
6073         if (stmt != NULL) {
6074                 while (stmt->base.next != NULL)
6075                         stmt = stmt->base.next;
6076
6077                 if (stmt->kind == STATEMENT_EXPRESSION) {
6078                         type = stmt->expression.expression->base.type;
6079                 }
6080         } else {
6081                 warningf(&expression->base.source_position, "empty statement expression ({})");
6082         }
6083         expression->base.type = type;
6084
6085         expect(')');
6086
6087         return expression;
6088 end_error:
6089         return create_invalid_expression();
6090 }
6091
6092 /**
6093  * Parse a parenthesized expression.
6094  */
6095 static expression_t *parse_parenthesized_expression(void)
6096 {
6097         eat('(');
6098         add_anchor_token(')');
6099
6100         switch(token.type) {
6101         case '{':
6102                 /* gcc extension: a statement expression */
6103                 return parse_statement_expression();
6104
6105         TYPE_QUALIFIERS
6106         TYPE_SPECIFIERS
6107                 return parse_cast();
6108         case T_IDENTIFIER:
6109                 if (is_typedef_symbol(token.v.symbol)) {
6110                         return parse_cast();
6111                 }
6112         }
6113
6114         expression_t *result = parse_expression();
6115         rem_anchor_token(')');
6116         expect(')');
6117
6118         return result;
6119 end_error:
6120         return create_invalid_expression();
6121 }
6122
6123 static expression_t *parse_function_keyword(void)
6124 {
6125         next_token();
6126         /* TODO */
6127
6128         if (current_function == NULL) {
6129                 errorf(HERE, "'__func__' used outside of a function");
6130         }
6131
6132         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6133         expression->base.type     = type_char_ptr;
6134         expression->funcname.kind = FUNCNAME_FUNCTION;
6135
6136         return expression;
6137 }
6138
6139 static expression_t *parse_pretty_function_keyword(void)
6140 {
6141         eat(T___PRETTY_FUNCTION__);
6142
6143         if (current_function == NULL) {
6144                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
6145         }
6146
6147         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6148         expression->base.type     = type_char_ptr;
6149         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
6150
6151         return expression;
6152 }
6153
6154 static expression_t *parse_funcsig_keyword(void)
6155 {
6156         eat(T___FUNCSIG__);
6157
6158         if (current_function == NULL) {
6159                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
6160         }
6161
6162         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6163         expression->base.type     = type_char_ptr;
6164         expression->funcname.kind = FUNCNAME_FUNCSIG;
6165
6166         return expression;
6167 }
6168
6169 static expression_t *parse_funcdname_keyword(void)
6170 {
6171         eat(T___FUNCDNAME__);
6172
6173         if (current_function == NULL) {
6174                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
6175         }
6176
6177         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6178         expression->base.type     = type_char_ptr;
6179         expression->funcname.kind = FUNCNAME_FUNCDNAME;
6180
6181         return expression;
6182 }
6183
6184 static designator_t *parse_designator(void)
6185 {
6186         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
6187         result->source_position = *HERE;
6188
6189         if (token.type != T_IDENTIFIER) {
6190                 parse_error_expected("while parsing member designator",
6191                                      T_IDENTIFIER, NULL);
6192                 return NULL;
6193         }
6194         result->symbol = token.v.symbol;
6195         next_token();
6196
6197         designator_t *last_designator = result;
6198         while(true) {
6199                 if (token.type == '.') {
6200                         next_token();
6201                         if (token.type != T_IDENTIFIER) {
6202                                 parse_error_expected("while parsing member designator",
6203                                                      T_IDENTIFIER, NULL);
6204                                 return NULL;
6205                         }
6206                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6207                         designator->source_position = *HERE;
6208                         designator->symbol          = token.v.symbol;
6209                         next_token();
6210
6211                         last_designator->next = designator;
6212                         last_designator       = designator;
6213                         continue;
6214                 }
6215                 if (token.type == '[') {
6216                         next_token();
6217                         add_anchor_token(']');
6218                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6219                         designator->source_position = *HERE;
6220                         designator->array_index     = parse_expression();
6221                         rem_anchor_token(']');
6222                         expect(']');
6223                         if (designator->array_index == NULL) {
6224                                 return NULL;
6225                         }
6226
6227                         last_designator->next = designator;
6228                         last_designator       = designator;
6229                         continue;
6230                 }
6231                 break;
6232         }
6233
6234         return result;
6235 end_error:
6236         return NULL;
6237 }
6238
6239 /**
6240  * Parse the __builtin_offsetof() expression.
6241  */
6242 static expression_t *parse_offsetof(void)
6243 {
6244         eat(T___builtin_offsetof);
6245
6246         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6247         expression->base.type    = type_size_t;
6248
6249         expect('(');
6250         add_anchor_token(',');
6251         type_t *type = parse_typename();
6252         rem_anchor_token(',');
6253         expect(',');
6254         add_anchor_token(')');
6255         designator_t *designator = parse_designator();
6256         rem_anchor_token(')');
6257         expect(')');
6258
6259         expression->offsetofe.type       = type;
6260         expression->offsetofe.designator = designator;
6261
6262         type_path_t path;
6263         memset(&path, 0, sizeof(path));
6264         path.top_type = type;
6265         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6266
6267         descend_into_subtype(&path);
6268
6269         if (!walk_designator(&path, designator, true)) {
6270                 return create_invalid_expression();
6271         }
6272
6273         DEL_ARR_F(path.path);
6274
6275         return expression;
6276 end_error:
6277         return create_invalid_expression();
6278 }
6279
6280 /**
6281  * Parses a _builtin_va_start() expression.
6282  */
6283 static expression_t *parse_va_start(void)
6284 {
6285         eat(T___builtin_va_start);
6286
6287         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6288
6289         expect('(');
6290         add_anchor_token(',');
6291         expression->va_starte.ap = parse_assignment_expression();
6292         rem_anchor_token(',');
6293         expect(',');
6294         expression_t *const expr = parse_assignment_expression();
6295         if (expr->kind == EXPR_REFERENCE) {
6296                 declaration_t *const decl = expr->reference.declaration;
6297                 if (decl == NULL)
6298                         return create_invalid_expression();
6299                 if (decl->parent_scope == &current_function->scope &&
6300                     decl->next == NULL) {
6301                         expression->va_starte.parameter = decl;
6302                         expect(')');
6303                         return expression;
6304                 }
6305         }
6306         errorf(&expr->base.source_position,
6307                "second argument of 'va_start' must be last parameter of the current function");
6308 end_error:
6309         return create_invalid_expression();
6310 }
6311
6312 /**
6313  * Parses a _builtin_va_arg() expression.
6314  */
6315 static expression_t *parse_va_arg(void)
6316 {
6317         eat(T___builtin_va_arg);
6318
6319         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6320
6321         expect('(');
6322         expression->va_arge.ap = parse_assignment_expression();
6323         expect(',');
6324         expression->base.type = parse_typename();
6325         expect(')');
6326
6327         return expression;
6328 end_error:
6329         return create_invalid_expression();
6330 }
6331
6332 static expression_t *parse_builtin_symbol(void)
6333 {
6334         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
6335
6336         symbol_t *symbol = token.v.symbol;
6337
6338         expression->builtin_symbol.symbol = symbol;
6339         next_token();
6340
6341         type_t *type = get_builtin_symbol_type(symbol);
6342         type = automatic_type_conversion(type);
6343
6344         expression->base.type = type;
6345         return expression;
6346 }
6347
6348 /**
6349  * Parses a __builtin_constant() expression.
6350  */
6351 static expression_t *parse_builtin_constant(void)
6352 {
6353         eat(T___builtin_constant_p);
6354
6355         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6356
6357         expect('(');
6358         add_anchor_token(')');
6359         expression->builtin_constant.value = parse_assignment_expression();
6360         rem_anchor_token(')');
6361         expect(')');
6362         expression->base.type = type_int;
6363
6364         return expression;
6365 end_error:
6366         return create_invalid_expression();
6367 }
6368
6369 /**
6370  * Parses a __builtin_prefetch() expression.
6371  */
6372 static expression_t *parse_builtin_prefetch(void)
6373 {
6374         eat(T___builtin_prefetch);
6375
6376         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
6377
6378         expect('(');
6379         add_anchor_token(')');
6380         expression->builtin_prefetch.adr = parse_assignment_expression();
6381         if (token.type == ',') {
6382                 next_token();
6383                 expression->builtin_prefetch.rw = parse_assignment_expression();
6384         }
6385         if (token.type == ',') {
6386                 next_token();
6387                 expression->builtin_prefetch.locality = parse_assignment_expression();
6388         }
6389         rem_anchor_token(')');
6390         expect(')');
6391         expression->base.type = type_void;
6392
6393         return expression;
6394 end_error:
6395         return create_invalid_expression();
6396 }
6397
6398 /**
6399  * Parses a __builtin_is_*() compare expression.
6400  */
6401 static expression_t *parse_compare_builtin(void)
6402 {
6403         expression_t *expression;
6404
6405         switch(token.type) {
6406         case T___builtin_isgreater:
6407                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6408                 break;
6409         case T___builtin_isgreaterequal:
6410                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6411                 break;
6412         case T___builtin_isless:
6413                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6414                 break;
6415         case T___builtin_islessequal:
6416                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6417                 break;
6418         case T___builtin_islessgreater:
6419                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6420                 break;
6421         case T___builtin_isunordered:
6422                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6423                 break;
6424         default:
6425                 internal_errorf(HERE, "invalid compare builtin found");
6426                 break;
6427         }
6428         expression->base.source_position = *HERE;
6429         next_token();
6430
6431         expect('(');
6432         expression->binary.left = parse_assignment_expression();
6433         expect(',');
6434         expression->binary.right = parse_assignment_expression();
6435         expect(')');
6436
6437         type_t *const orig_type_left  = expression->binary.left->base.type;
6438         type_t *const orig_type_right = expression->binary.right->base.type;
6439
6440         type_t *const type_left  = skip_typeref(orig_type_left);
6441         type_t *const type_right = skip_typeref(orig_type_right);
6442         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6443                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6444                         type_error_incompatible("invalid operands in comparison",
6445                                 &expression->base.source_position, orig_type_left, orig_type_right);
6446                 }
6447         } else {
6448                 semantic_comparison(&expression->binary);
6449         }
6450
6451         return expression;
6452 end_error:
6453         return create_invalid_expression();
6454 }
6455
6456 #if 0
6457 /**
6458  * Parses a __builtin_expect() expression.
6459  */
6460 static expression_t *parse_builtin_expect(void)
6461 {
6462         eat(T___builtin_expect);
6463
6464         expression_t *expression
6465                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
6466
6467         expect('(');
6468         expression->binary.left = parse_assignment_expression();
6469         expect(',');
6470         expression->binary.right = parse_constant_expression();
6471         expect(')');
6472
6473         expression->base.type = expression->binary.left->base.type;
6474
6475         return expression;
6476 end_error:
6477         return create_invalid_expression();
6478 }
6479 #endif
6480
6481 /**
6482  * Parses a MS assume() expression.
6483  */
6484 static expression_t *parse_assume(void)
6485 {
6486         eat(T__assume);
6487
6488         expression_t *expression
6489                 = allocate_expression_zero(EXPR_UNARY_ASSUME);
6490
6491         expect('(');
6492         add_anchor_token(')');
6493         expression->unary.value = parse_assignment_expression();
6494         rem_anchor_token(')');
6495         expect(')');
6496
6497         expression->base.type = type_void;
6498         return expression;
6499 end_error:
6500         return create_invalid_expression();
6501 }
6502
6503 /**
6504  * Parse a microsoft __noop expression.
6505  */
6506 static expression_t *parse_noop_expression(void)
6507 {
6508         source_position_t source_position = *HERE;
6509         eat(T___noop);
6510
6511         if (token.type == '(') {
6512                 /* parse arguments */
6513                 eat('(');
6514                 add_anchor_token(')');
6515                 add_anchor_token(',');
6516
6517                 if (token.type != ')') {
6518                         while(true) {
6519                                 (void)parse_assignment_expression();
6520                                 if (token.type != ',')
6521                                         break;
6522                                 next_token();
6523                         }
6524                 }
6525         }
6526         rem_anchor_token(',');
6527         rem_anchor_token(')');
6528         expect(')');
6529
6530         /* the result is a (int)0 */
6531         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6532         cnst->base.source_position = source_position;
6533         cnst->base.type            = type_int;
6534         cnst->conste.v.int_value   = 0;
6535         cnst->conste.is_ms_noop    = true;
6536
6537         return cnst;
6538
6539 end_error:
6540         return create_invalid_expression();
6541 }
6542
6543 /**
6544  * Parses a primary expression.
6545  */
6546 static expression_t *parse_primary_expression(void)
6547 {
6548         switch (token.type) {
6549                 case T_INTEGER:                  return parse_int_const();
6550                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
6551                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
6552                 case T_FLOATINGPOINT:            return parse_float_const();
6553                 case T_STRING_LITERAL:
6554                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
6555                 case T_IDENTIFIER:               return parse_reference();
6556                 case T___FUNCTION__:
6557                 case T___func__:                 return parse_function_keyword();
6558                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
6559                 case T___FUNCSIG__:              return parse_funcsig_keyword();
6560                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
6561                 case T___builtin_offsetof:       return parse_offsetof();
6562                 case T___builtin_va_start:       return parse_va_start();
6563                 case T___builtin_va_arg:         return parse_va_arg();
6564                 case T___builtin_expect:
6565                 case T___builtin_alloca:
6566                 case T___builtin_nan:
6567                 case T___builtin_nand:
6568                 case T___builtin_nanf:
6569                 case T___builtin_huge_val:
6570                 case T___builtin_va_end:         return parse_builtin_symbol();
6571                 case T___builtin_isgreater:
6572                 case T___builtin_isgreaterequal:
6573                 case T___builtin_isless:
6574                 case T___builtin_islessequal:
6575                 case T___builtin_islessgreater:
6576                 case T___builtin_isunordered:    return parse_compare_builtin();
6577                 case T___builtin_constant_p:     return parse_builtin_constant();
6578                 case T___builtin_prefetch:       return parse_builtin_prefetch();
6579                 case T__assume:                  return parse_assume();
6580
6581                 case '(':                        return parse_parenthesized_expression();
6582                 case T___noop:                   return parse_noop_expression();
6583         }
6584
6585         errorf(HERE, "unexpected token %K, expected an expression", &token);
6586         return create_invalid_expression();
6587 }
6588
6589 /**
6590  * Check if the expression has the character type and issue a warning then.
6591  */
6592 static void check_for_char_index_type(const expression_t *expression)
6593 {
6594         type_t       *const type      = expression->base.type;
6595         const type_t *const base_type = skip_typeref(type);
6596
6597         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
6598                         warning.char_subscripts) {
6599                 warningf(&expression->base.source_position,
6600                          "array subscript has type '%T'", type);
6601         }
6602 }
6603
6604 static expression_t *parse_array_expression(unsigned precedence,
6605                                             expression_t *left)
6606 {
6607         (void) precedence;
6608
6609         eat('[');
6610         add_anchor_token(']');
6611
6612         expression_t *inside = parse_expression();
6613
6614         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
6615
6616         array_access_expression_t *array_access = &expression->array_access;
6617
6618         type_t *const orig_type_left   = left->base.type;
6619         type_t *const orig_type_inside = inside->base.type;
6620
6621         type_t *const type_left   = skip_typeref(orig_type_left);
6622         type_t *const type_inside = skip_typeref(orig_type_inside);
6623
6624         type_t *return_type;
6625         if (is_type_pointer(type_left)) {
6626                 return_type             = type_left->pointer.points_to;
6627                 array_access->array_ref = left;
6628                 array_access->index     = inside;
6629                 check_for_char_index_type(inside);
6630         } else if (is_type_pointer(type_inside)) {
6631                 return_type             = type_inside->pointer.points_to;
6632                 array_access->array_ref = inside;
6633                 array_access->index     = left;
6634                 array_access->flipped   = true;
6635                 check_for_char_index_type(left);
6636         } else {
6637                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
6638                         errorf(HERE,
6639                                 "array access on object with non-pointer types '%T', '%T'",
6640                                 orig_type_left, orig_type_inside);
6641                 }
6642                 return_type             = type_error_type;
6643                 array_access->array_ref = create_invalid_expression();
6644         }
6645
6646         rem_anchor_token(']');
6647         if (token.type != ']') {
6648                 parse_error_expected("Problem while parsing array access", ']', NULL);
6649                 return expression;
6650         }
6651         next_token();
6652
6653         return_type           = automatic_type_conversion(return_type);
6654         expression->base.type = return_type;
6655
6656         return expression;
6657 }
6658
6659 static expression_t *parse_typeprop(expression_kind_t const kind,
6660                                     source_position_t const pos,
6661                                     unsigned const precedence)
6662 {
6663         expression_t *tp_expression = allocate_expression_zero(kind);
6664         tp_expression->base.type            = type_size_t;
6665         tp_expression->base.source_position = pos;
6666
6667         char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
6668
6669         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
6670                 next_token();
6671                 add_anchor_token(')');
6672                 type_t* const orig_type = parse_typename();
6673                 tp_expression->typeprop.type = orig_type;
6674
6675                 type_t const* const type = skip_typeref(orig_type);
6676                 char const* const wrong_type =
6677                         is_type_incomplete(type)    ? "incomplete"          :
6678                         type->kind == TYPE_FUNCTION ? "function designator" :
6679                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6680                         NULL;
6681                 if (wrong_type != NULL) {
6682                         errorf(&pos, "operand of %s expression must not be %s type '%T'",
6683                                what, wrong_type, type);
6684                 }
6685
6686                 rem_anchor_token(')');
6687                 expect(')');
6688         } else {
6689                 expression_t *expression = parse_sub_expression(precedence);
6690
6691                 type_t* const orig_type = revert_automatic_type_conversion(expression);
6692                 expression->base.type = orig_type;
6693
6694                 type_t const* const type = skip_typeref(orig_type);
6695                 char const* const wrong_type =
6696                         is_type_incomplete(type)    ? "incomplete"          :
6697                         type->kind == TYPE_FUNCTION ? "function designator" :
6698                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6699                         NULL;
6700                 if (wrong_type != NULL) {
6701                         errorf(&pos, "operand of %s expression must not be expression of %s type '%T'", what, wrong_type, type);
6702                 }
6703
6704                 tp_expression->typeprop.type          = expression->base.type;
6705                 tp_expression->typeprop.tp_expression = expression;
6706         }
6707
6708         return tp_expression;
6709 end_error:
6710         return create_invalid_expression();
6711 }
6712
6713 static expression_t *parse_sizeof(unsigned precedence)
6714 {
6715         source_position_t pos = *HERE;
6716         eat(T_sizeof);
6717         return parse_typeprop(EXPR_SIZEOF, pos, precedence);
6718 }
6719
6720 static expression_t *parse_alignof(unsigned precedence)
6721 {
6722         source_position_t pos = *HERE;
6723         eat(T___alignof__);
6724         return parse_typeprop(EXPR_ALIGNOF, pos, precedence);
6725 }
6726
6727 static expression_t *parse_select_expression(unsigned precedence,
6728                                              expression_t *compound)
6729 {
6730         (void) precedence;
6731         assert(token.type == '.' || token.type == T_MINUSGREATER);
6732
6733         bool is_pointer = (token.type == T_MINUSGREATER);
6734         next_token();
6735
6736         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
6737         select->select.compound = compound;
6738
6739         if (token.type != T_IDENTIFIER) {
6740                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
6741                 return select;
6742         }
6743         symbol_t *symbol = token.v.symbol;
6744         next_token();
6745
6746         type_t *const orig_type = compound->base.type;
6747         type_t *const type      = skip_typeref(orig_type);
6748
6749         type_t *type_left = type;
6750         bool    saw_error = false;
6751         if (is_type_pointer(type)) {
6752                 if (!is_pointer) {
6753                         errorf(HERE,
6754                                "request for member '%Y' in something not a struct or union, but '%T'",
6755                                symbol, type_left);
6756                         saw_error = true;
6757                 }
6758                 type_left = type->pointer.points_to;
6759         } else if (is_pointer) {
6760                 if (is_type_valid(type)) {
6761                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
6762                         saw_error = true;
6763                 }
6764                 type_left = type;
6765         }
6766         type_left = skip_typeref(type_left);
6767
6768         declaration_t *entry;
6769         if (type_left->kind == TYPE_COMPOUND_STRUCT ||
6770             type_left->kind == TYPE_COMPOUND_UNION) {
6771                 declaration_t *const declaration = type_left->compound.declaration;
6772
6773                 if (!declaration->init.complete) {
6774                         errorf(HERE, "request for member '%Y' of incomplete type '%T'",
6775                                symbol, type_left);
6776                         return create_invalid_expression();
6777                 }
6778
6779                 entry = find_compound_entry(declaration, symbol);
6780                 if (entry == NULL) {
6781                         errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
6782                         goto create_error_entry;
6783                 }
6784         } else {
6785                 if (is_type_valid(type_left) && !saw_error) {
6786                         errorf(HERE,
6787                                "request for member '%Y' in something not a struct or union, but '%T'",
6788                                symbol, type_left);
6789                 }
6790 create_error_entry:
6791                 entry         = allocate_declaration_zero();
6792                 entry->symbol = symbol;
6793         }
6794
6795         select->select.compound_entry = entry;
6796         /* we always do the auto-type conversions; the & and sizeof parser contains
6797          * code to revert this! */
6798         select->base.type = automatic_type_conversion(entry->type);
6799
6800         type_t *skipped = skip_typeref(entry->type);
6801         if (skipped->kind == TYPE_BITFIELD) {
6802                 select->base.type = skipped->bitfield.base_type;
6803         }
6804
6805         return select;
6806 }
6807
6808 static void check_call_argument(const function_parameter_t *parameter,
6809                                 call_argument_t *argument, unsigned pos)
6810 {
6811         type_t         *expected_type      = parameter->type;
6812         type_t         *expected_type_skip = skip_typeref(expected_type);
6813         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
6814         expression_t   *arg_expr           = argument->expression;
6815         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
6816
6817         /* handle transparent union gnu extension */
6818         if (is_type_union(expected_type_skip)
6819                         && (expected_type_skip->base.modifiers
6820                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
6821                 declaration_t  *union_decl = expected_type_skip->compound.declaration;
6822
6823                 declaration_t *declaration = union_decl->scope.declarations;
6824                 type_t        *best_type   = NULL;
6825                 for ( ; declaration != NULL; declaration = declaration->next) {
6826                         type_t *decl_type = declaration->type;
6827                         error = semantic_assign(decl_type, arg_expr);
6828                         if (error == ASSIGN_ERROR_INCOMPATIBLE
6829                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
6830                                 continue;
6831
6832                         if (error == ASSIGN_SUCCESS) {
6833                                 best_type = decl_type;
6834                         } else if (best_type == NULL) {
6835                                 best_type = decl_type;
6836                         }
6837                 }
6838
6839                 if (best_type != NULL) {
6840                         expected_type = best_type;
6841                 }
6842         }
6843
6844         error                = semantic_assign(expected_type, arg_expr);
6845         argument->expression = create_implicit_cast(argument->expression,
6846                                                     expected_type);
6847
6848         if (error != ASSIGN_SUCCESS) {
6849                 /* report exact scope in error messages (like "in argument 3") */
6850                 char buf[64];
6851                 snprintf(buf, sizeof(buf), "call argument %u", pos);
6852                 report_assign_error(error, expected_type, arg_expr,     buf,
6853                                                         &arg_expr->base.source_position);
6854         } else if (warning.traditional | warning.conversion) {
6855                 if (
6856                     /* passing as integer instead of float or complex */
6857                     (is_type_integer(expected_type) &&
6858                      (is_type_float(arg_type) || is_type_complex(arg_type))) ||
6859                     /* passing as complex instead of integer or float */
6860                     (is_type_complex(expected_type) &&
6861                      (is_type_integer(arg_type) || is_type_float(arg_type))) ||
6862                     /* passing as float instead of integer or complex */
6863                     (is_type_float(expected_type) &&
6864                      (is_type_integer(arg_type) || is_type_complex(arg_type))) ||
6865                     /* passing as float instead of double */
6866                     (is_type_float(expected_type) && expected_type != type_double &&
6867                      is_type_float(arg_type))) {
6868                         warningf(&arg_expr->base.source_position,
6869                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
6870                                 pos, expected_type, arg_type);
6871                 }
6872                 if (is_type_integer(expected_type) && is_type_integer(arg_type)) {
6873                         /* TODO check for size HERE */
6874                 }
6875         }
6876 }
6877
6878 /**
6879  * Parse a call expression, ie. expression '( ... )'.
6880  *
6881  * @param expression  the function address
6882  */
6883 static expression_t *parse_call_expression(unsigned precedence,
6884                                            expression_t *expression)
6885 {
6886         (void) precedence;
6887         expression_t *result = allocate_expression_zero(EXPR_CALL);
6888         result->base.source_position = expression->base.source_position;
6889
6890         call_expression_t *call = &result->call;
6891         call->function          = expression;
6892
6893         type_t *const orig_type = expression->base.type;
6894         type_t *const type      = skip_typeref(orig_type);
6895
6896         function_type_t *function_type = NULL;
6897         if (is_type_pointer(type)) {
6898                 type_t *const to_type = skip_typeref(type->pointer.points_to);
6899
6900                 if (is_type_function(to_type)) {
6901                         function_type   = &to_type->function;
6902                         call->base.type = function_type->return_type;
6903                 }
6904         }
6905
6906         if (function_type == NULL && is_type_valid(type)) {
6907                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
6908         }
6909
6910         /* parse arguments */
6911         eat('(');
6912         add_anchor_token(')');
6913         add_anchor_token(',');
6914
6915         if (token.type != ')') {
6916                 call_argument_t *last_argument = NULL;
6917
6918                 while (true) {
6919                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
6920
6921                         argument->expression = parse_assignment_expression();
6922                         if (last_argument == NULL) {
6923                                 call->arguments = argument;
6924                         } else {
6925                                 last_argument->next = argument;
6926                         }
6927                         last_argument = argument;
6928
6929                         if (token.type != ',')
6930                                 break;
6931                         next_token();
6932                 }
6933         }
6934         rem_anchor_token(',');
6935         rem_anchor_token(')');
6936         expect(')');
6937
6938         if (function_type == NULL)
6939                 return result;
6940
6941         function_parameter_t *parameter = function_type->parameters;
6942         call_argument_t      *argument  = call->arguments;
6943         if (!function_type->unspecified_parameters) {
6944                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
6945                                 parameter = parameter->next, argument = argument->next) {
6946                         check_call_argument(parameter, argument, ++pos);
6947                 }
6948
6949                 if (parameter != NULL) {
6950                         errorf(HERE, "too few arguments to function '%E'", expression);
6951                 } else if (argument != NULL && !function_type->variadic) {
6952                         errorf(HERE, "too many arguments to function '%E'", expression);
6953                 }
6954         }
6955
6956         /* do default promotion */
6957         for( ; argument != NULL; argument = argument->next) {
6958                 type_t *type = argument->expression->base.type;
6959
6960                 type = get_default_promoted_type(type);
6961
6962                 argument->expression
6963                         = create_implicit_cast(argument->expression, type);
6964         }
6965
6966         check_format(&result->call);
6967
6968         if (warning.aggregate_return &&
6969             is_type_compound(skip_typeref(function_type->return_type))) {
6970                 warningf(&result->base.source_position,
6971                          "function call has aggregate value");
6972         }
6973
6974         return result;
6975 end_error:
6976         return create_invalid_expression();
6977 }
6978
6979 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
6980
6981 static bool same_compound_type(const type_t *type1, const type_t *type2)
6982 {
6983         return
6984                 is_type_compound(type1) &&
6985                 type1->kind == type2->kind &&
6986                 type1->compound.declaration == type2->compound.declaration;
6987 }
6988
6989 /**
6990  * Parse a conditional expression, ie. 'expression ? ... : ...'.
6991  *
6992  * @param expression  the conditional expression
6993  */
6994 static expression_t *parse_conditional_expression(unsigned precedence,
6995                                                   expression_t *expression)
6996 {
6997         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
6998
6999         conditional_expression_t *conditional = &result->conditional;
7000         conditional->base.source_position = *HERE;
7001         conditional->condition            = expression;
7002
7003         eat('?');
7004         add_anchor_token(':');
7005
7006         /* 6.5.15.2 */
7007         type_t *const condition_type_orig = expression->base.type;
7008         type_t *const condition_type      = skip_typeref(condition_type_orig);
7009         if (!is_type_scalar(condition_type) && is_type_valid(condition_type)) {
7010                 type_error("expected a scalar type in conditional condition",
7011                            &expression->base.source_position, condition_type_orig);
7012         }
7013
7014         expression_t *true_expression = expression;
7015         bool          gnu_cond = false;
7016         if ((c_mode & _GNUC) && token.type == ':') {
7017                 gnu_cond = true;
7018         } else
7019                 true_expression = parse_expression();
7020         rem_anchor_token(':');
7021         expect(':');
7022         expression_t *false_expression = parse_sub_expression(precedence);
7023
7024         type_t *const orig_true_type  = true_expression->base.type;
7025         type_t *const orig_false_type = false_expression->base.type;
7026         type_t *const true_type       = skip_typeref(orig_true_type);
7027         type_t *const false_type      = skip_typeref(orig_false_type);
7028
7029         /* 6.5.15.3 */
7030         type_t *result_type;
7031         if (is_type_atomic(true_type, ATOMIC_TYPE_VOID) ||
7032                 is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7033                 if (!is_type_atomic(true_type, ATOMIC_TYPE_VOID)
7034                     || !is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7035                         warningf(&conditional->base.source_position,
7036                                         "ISO C forbids conditional expression with only one void side");
7037                 }
7038                 result_type = type_void;
7039         } else if (is_type_arithmetic(true_type)
7040                    && is_type_arithmetic(false_type)) {
7041                 result_type = semantic_arithmetic(true_type, false_type);
7042
7043                 true_expression  = create_implicit_cast(true_expression, result_type);
7044                 false_expression = create_implicit_cast(false_expression, result_type);
7045
7046                 conditional->true_expression  = true_expression;
7047                 conditional->false_expression = false_expression;
7048                 conditional->base.type        = result_type;
7049         } else if (same_compound_type(true_type, false_type)) {
7050                 /* just take 1 of the 2 types */
7051                 result_type = true_type;
7052         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
7053                 type_t *pointer_type;
7054                 type_t *other_type;
7055                 expression_t *other_expression;
7056                 if (is_type_pointer(true_type) &&
7057                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
7058                         pointer_type     = true_type;
7059                         other_type       = false_type;
7060                         other_expression = false_expression;
7061                 } else {
7062                         pointer_type     = false_type;
7063                         other_type       = true_type;
7064                         other_expression = true_expression;
7065                 }
7066
7067                 if (is_null_pointer_constant(other_expression)) {
7068                         result_type = pointer_type;
7069                 } else if (is_type_pointer(other_type)) {
7070                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
7071                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
7072
7073                         type_t *to;
7074                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
7075                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
7076                                 to = type_void;
7077                         } else if (types_compatible(get_unqualified_type(to1),
7078                                                     get_unqualified_type(to2))) {
7079                                 to = to1;
7080                         } else {
7081                                 warningf(&conditional->base.source_position,
7082                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
7083                                         true_type, false_type);
7084                                 to = type_void;
7085                         }
7086
7087                         type_t *const copy = duplicate_type(to);
7088                         copy->base.qualifiers = to1->base.qualifiers | to2->base.qualifiers;
7089
7090                         type_t *const type = typehash_insert(copy);
7091                         if (type != copy)
7092                                 free_type(copy);
7093
7094                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
7095                 } else if (is_type_integer(other_type)) {
7096                         warningf(&conditional->base.source_position,
7097                                         "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
7098                         result_type = pointer_type;
7099                 } else {
7100                         type_error_incompatible("while parsing conditional",
7101                                         &expression->base.source_position, true_type, false_type);
7102                         result_type = type_error_type;
7103                 }
7104         } else {
7105                 /* TODO: one pointer to void*, other some pointer */
7106
7107                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
7108                         type_error_incompatible("while parsing conditional",
7109                                                 &conditional->base.source_position, true_type,
7110                                                 false_type);
7111                 }
7112                 result_type = type_error_type;
7113         }
7114
7115         conditional->true_expression
7116                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
7117         conditional->false_expression
7118                 = create_implicit_cast(false_expression, result_type);
7119         conditional->base.type = result_type;
7120         return result;
7121 end_error:
7122         return create_invalid_expression();
7123 }
7124
7125 /**
7126  * Parse an extension expression.
7127  */
7128 static expression_t *parse_extension(unsigned precedence)
7129 {
7130         eat(T___extension__);
7131
7132         /* TODO enable extensions */
7133         expression_t *expression = parse_sub_expression(precedence);
7134         /* TODO disable extensions */
7135         return expression;
7136 }
7137
7138 /**
7139  * Parse a __builtin_classify_type() expression.
7140  */
7141 static expression_t *parse_builtin_classify_type(const unsigned precedence)
7142 {
7143         eat(T___builtin_classify_type);
7144
7145         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
7146         result->base.type    = type_int;
7147
7148         expect('(');
7149         add_anchor_token(')');
7150         expression_t *expression = parse_sub_expression(precedence);
7151         rem_anchor_token(')');
7152         expect(')');
7153         result->classify_type.type_expression = expression;
7154
7155         return result;
7156 end_error:
7157         return create_invalid_expression();
7158 }
7159
7160 static bool check_pointer_arithmetic(const source_position_t *source_position,
7161                                      type_t *pointer_type,
7162                                      type_t *orig_pointer_type)
7163 {
7164         type_t *points_to = pointer_type->pointer.points_to;
7165         points_to = skip_typeref(points_to);
7166
7167         if (is_type_incomplete(points_to)) {
7168                 if (!(c_mode & _GNUC) || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7169                         errorf(source_position,
7170                                "arithmetic with pointer to incomplete type '%T' not allowed",
7171                                orig_pointer_type);
7172                         return false;
7173                 } else if (warning.pointer_arith) {
7174                         warningf(source_position,
7175                                  "pointer of type '%T' used in arithmetic",
7176                                  orig_pointer_type);
7177                 }
7178         } else if (is_type_function(points_to)) {
7179                 if (!(c_mode && _GNUC)) {
7180                         errorf(source_position,
7181                                "arithmetic with pointer to function type '%T' not allowed",
7182                                orig_pointer_type);
7183                         return false;
7184                 } else if (warning.pointer_arith) {
7185                         warningf(source_position,
7186                                  "pointer to a function '%T' used in arithmetic",
7187                                  orig_pointer_type);
7188                 }
7189         }
7190         return true;
7191 }
7192
7193 static bool is_lvalue(const expression_t *expression)
7194 {
7195         switch (expression->kind) {
7196         case EXPR_REFERENCE:
7197         case EXPR_ARRAY_ACCESS:
7198         case EXPR_SELECT:
7199         case EXPR_UNARY_DEREFERENCE:
7200                 return true;
7201
7202         default:
7203                 return false;
7204         }
7205 }
7206
7207 static void semantic_incdec(unary_expression_t *expression)
7208 {
7209         type_t *const orig_type = expression->value->base.type;
7210         type_t *const type      = skip_typeref(orig_type);
7211         if (is_type_pointer(type)) {
7212                 if (!check_pointer_arithmetic(&expression->base.source_position,
7213                                               type, orig_type)) {
7214                         return;
7215                 }
7216         } else if (!is_type_real(type) && is_type_valid(type)) {
7217                 /* TODO: improve error message */
7218                 errorf(&expression->base.source_position,
7219                        "operation needs an arithmetic or pointer type");
7220                 return;
7221         }
7222         if (!is_lvalue(expression->value)) {
7223                 /* TODO: improve error message */
7224                 errorf(&expression->base.source_position, "lvalue required as operand");
7225         }
7226         expression->base.type = orig_type;
7227 }
7228
7229 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
7230 {
7231         type_t *const orig_type = expression->value->base.type;
7232         type_t *const type      = skip_typeref(orig_type);
7233         if (!is_type_arithmetic(type)) {
7234                 if (is_type_valid(type)) {
7235                         /* TODO: improve error message */
7236                         errorf(&expression->base.source_position,
7237                                 "operation needs an arithmetic type");
7238                 }
7239                 return;
7240         }
7241
7242         expression->base.type = orig_type;
7243 }
7244
7245 static void semantic_unexpr_plus(unary_expression_t *expression)
7246 {
7247         semantic_unexpr_arithmetic(expression);
7248         if (warning.traditional)
7249                 warningf(&expression->base.source_position,
7250                         "traditional C rejects the unary plus operator");
7251 }
7252
7253 static void semantic_not(unary_expression_t *expression)
7254 {
7255         type_t *const orig_type = expression->value->base.type;
7256         type_t *const type      = skip_typeref(orig_type);
7257         if (!is_type_scalar(type) && is_type_valid(type)) {
7258                 errorf(&expression->base.source_position,
7259                        "operand of ! must be of scalar type");
7260         }
7261
7262         expression->base.type = type_int;
7263 }
7264
7265 static void semantic_unexpr_integer(unary_expression_t *expression)
7266 {
7267         type_t *const orig_type = expression->value->base.type;
7268         type_t *const type      = skip_typeref(orig_type);
7269         if (!is_type_integer(type)) {
7270                 if (is_type_valid(type)) {
7271                         errorf(&expression->base.source_position,
7272                                "operand of ~ must be of integer type");
7273                 }
7274                 return;
7275         }
7276
7277         expression->base.type = orig_type;
7278 }
7279
7280 static void semantic_dereference(unary_expression_t *expression)
7281 {
7282         type_t *const orig_type = expression->value->base.type;
7283         type_t *const type      = skip_typeref(orig_type);
7284         if (!is_type_pointer(type)) {
7285                 if (is_type_valid(type)) {
7286                         errorf(&expression->base.source_position,
7287                                "Unary '*' needs pointer or arrray type, but type '%T' given", orig_type);
7288                 }
7289                 return;
7290         }
7291
7292         type_t *result_type   = type->pointer.points_to;
7293         result_type           = automatic_type_conversion(result_type);
7294         expression->base.type = result_type;
7295 }
7296
7297 /**
7298  * Record that an address is taken (expression represents an lvalue).
7299  *
7300  * @param expression       the expression
7301  * @param may_be_register  if true, the expression might be an register
7302  */
7303 static void set_address_taken(expression_t *expression, bool may_be_register)
7304 {
7305         if (expression->kind != EXPR_REFERENCE)
7306                 return;
7307
7308         declaration_t *const declaration = expression->reference.declaration;
7309         /* happens for parse errors */
7310         if (declaration == NULL)
7311                 return;
7312
7313         if (declaration->storage_class == STORAGE_CLASS_REGISTER && !may_be_register) {
7314                 errorf(&expression->base.source_position,
7315                                 "address of register variable '%Y' requested",
7316                                 declaration->symbol);
7317         } else {
7318                 declaration->address_taken = 1;
7319         }
7320 }
7321
7322 /**
7323  * Check the semantic of the address taken expression.
7324  */
7325 static void semantic_take_addr(unary_expression_t *expression)
7326 {
7327         expression_t *value = expression->value;
7328         value->base.type    = revert_automatic_type_conversion(value);
7329
7330         type_t *orig_type = value->base.type;
7331         if (!is_type_valid(orig_type))
7332                 return;
7333
7334         set_address_taken(value, false);
7335
7336         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
7337 }
7338
7339 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc)   \
7340 static expression_t *parse_##unexpression_type(unsigned precedence)            \
7341 {                                                                              \
7342         expression_t *unary_expression                                             \
7343                 = allocate_expression_zero(unexpression_type);                         \
7344         unary_expression->base.source_position = *HERE;                            \
7345         eat(token_type);                                                           \
7346         unary_expression->unary.value = parse_sub_expression(precedence);          \
7347                                                                                    \
7348         sfunc(&unary_expression->unary);                                           \
7349                                                                                    \
7350         return unary_expression;                                                   \
7351 }
7352
7353 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
7354                                semantic_unexpr_arithmetic)
7355 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
7356                                semantic_unexpr_plus)
7357 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
7358                                semantic_not)
7359 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
7360                                semantic_dereference)
7361 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
7362                                semantic_take_addr)
7363 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
7364                                semantic_unexpr_integer)
7365 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
7366                                semantic_incdec)
7367 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
7368                                semantic_incdec)
7369
7370 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
7371                                                sfunc)                         \
7372 static expression_t *parse_##unexpression_type(unsigned precedence,           \
7373                                                expression_t *left)            \
7374 {                                                                             \
7375         (void) precedence;                                                        \
7376                                                                               \
7377         expression_t *unary_expression                                            \
7378                 = allocate_expression_zero(unexpression_type);                        \
7379         unary_expression->base.source_position = *HERE;                           \
7380         eat(token_type);                                                          \
7381         unary_expression->unary.value          = left;                            \
7382                                                                                   \
7383         sfunc(&unary_expression->unary);                                          \
7384                                                                               \
7385         return unary_expression;                                                  \
7386 }
7387
7388 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
7389                                        EXPR_UNARY_POSTFIX_INCREMENT,
7390                                        semantic_incdec)
7391 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
7392                                        EXPR_UNARY_POSTFIX_DECREMENT,
7393                                        semantic_incdec)
7394
7395 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
7396 {
7397         /* TODO: handle complex + imaginary types */
7398
7399         /* § 6.3.1.8 Usual arithmetic conversions */
7400         if (type_left == type_long_double || type_right == type_long_double) {
7401                 return type_long_double;
7402         } else if (type_left == type_double || type_right == type_double) {
7403                 return type_double;
7404         } else if (type_left == type_float || type_right == type_float) {
7405                 return type_float;
7406         }
7407
7408         type_left  = promote_integer(type_left);
7409         type_right = promote_integer(type_right);
7410
7411         if (type_left == type_right)
7412                 return type_left;
7413
7414         bool const signed_left  = is_type_signed(type_left);
7415         bool const signed_right = is_type_signed(type_right);
7416         int const  rank_left    = get_rank(type_left);
7417         int const  rank_right   = get_rank(type_right);
7418
7419         if (signed_left == signed_right)
7420                 return rank_left >= rank_right ? type_left : type_right;
7421
7422         int     s_rank;
7423         int     u_rank;
7424         type_t *s_type;
7425         type_t *u_type;
7426         if (signed_left) {
7427                 s_rank = rank_left;
7428                 s_type = type_left;
7429                 u_rank = rank_right;
7430                 u_type = type_right;
7431         } else {
7432                 s_rank = rank_right;
7433                 s_type = type_right;
7434                 u_rank = rank_left;
7435                 u_type = type_left;
7436         }
7437
7438         if (u_rank >= s_rank)
7439                 return u_type;
7440
7441         /* casting rank to atomic_type_kind is a bit hacky, but makes things
7442          * easier here... */
7443         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
7444                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
7445                 return s_type;
7446
7447         switch (s_rank) {
7448                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
7449                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
7450                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
7451
7452                 default: panic("invalid atomic type");
7453         }
7454 }
7455
7456 /**
7457  * Check the semantic restrictions for a binary expression.
7458  */
7459 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
7460 {
7461         expression_t *const left            = expression->left;
7462         expression_t *const right           = expression->right;
7463         type_t       *const orig_type_left  = left->base.type;
7464         type_t       *const orig_type_right = right->base.type;
7465         type_t       *const type_left       = skip_typeref(orig_type_left);
7466         type_t       *const type_right      = skip_typeref(orig_type_right);
7467
7468         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7469                 /* TODO: improve error message */
7470                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7471                         errorf(&expression->base.source_position,
7472                                "operation needs arithmetic types");
7473                 }
7474                 return;
7475         }
7476
7477         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7478         expression->left      = create_implicit_cast(left, arithmetic_type);
7479         expression->right     = create_implicit_cast(right, arithmetic_type);
7480         expression->base.type = arithmetic_type;
7481 }
7482
7483 static void warn_div_by_zero(binary_expression_t const *const expression)
7484 {
7485         if (warning.div_by_zero                       &&
7486             is_type_integer(expression->base.type)    &&
7487             is_constant_expression(expression->right) &&
7488             fold_constant(expression->right) == 0) {
7489                 warningf(&expression->base.source_position, "division by zero");
7490         }
7491 }
7492
7493 /**
7494  * Check the semantic restrictions for a div/mod expression.
7495  */
7496 static void semantic_divmod_arithmetic(binary_expression_t *expression) {
7497         semantic_binexpr_arithmetic(expression);
7498         warn_div_by_zero(expression);
7499 }
7500
7501 static void semantic_shift_op(binary_expression_t *expression)
7502 {
7503         expression_t *const left            = expression->left;
7504         expression_t *const right           = expression->right;
7505         type_t       *const orig_type_left  = left->base.type;
7506         type_t       *const orig_type_right = right->base.type;
7507         type_t       *      type_left       = skip_typeref(orig_type_left);
7508         type_t       *      type_right      = skip_typeref(orig_type_right);
7509
7510         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
7511                 /* TODO: improve error message */
7512                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7513                         errorf(&expression->base.source_position,
7514                                "operands of shift operation must have integer types");
7515                 }
7516                 return;
7517         }
7518
7519         type_left  = promote_integer(type_left);
7520         type_right = promote_integer(type_right);
7521
7522         expression->left      = create_implicit_cast(left, type_left);
7523         expression->right     = create_implicit_cast(right, type_right);
7524         expression->base.type = type_left;
7525 }
7526
7527 static void semantic_add(binary_expression_t *expression)
7528 {
7529         expression_t *const left            = expression->left;
7530         expression_t *const right           = expression->right;
7531         type_t       *const orig_type_left  = left->base.type;
7532         type_t       *const orig_type_right = right->base.type;
7533         type_t       *const type_left       = skip_typeref(orig_type_left);
7534         type_t       *const type_right      = skip_typeref(orig_type_right);
7535
7536         /* § 6.5.6 */
7537         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7538                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7539                 expression->left  = create_implicit_cast(left, arithmetic_type);
7540                 expression->right = create_implicit_cast(right, arithmetic_type);
7541                 expression->base.type = arithmetic_type;
7542                 return;
7543         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7544                 check_pointer_arithmetic(&expression->base.source_position,
7545                                          type_left, orig_type_left);
7546                 expression->base.type = type_left;
7547         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
7548                 check_pointer_arithmetic(&expression->base.source_position,
7549                                          type_right, orig_type_right);
7550                 expression->base.type = type_right;
7551         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7552                 errorf(&expression->base.source_position,
7553                        "invalid operands to binary + ('%T', '%T')",
7554                        orig_type_left, orig_type_right);
7555         }
7556 }
7557
7558 static void semantic_sub(binary_expression_t *expression)
7559 {
7560         expression_t            *const left            = expression->left;
7561         expression_t            *const right           = expression->right;
7562         type_t                  *const orig_type_left  = left->base.type;
7563         type_t                  *const orig_type_right = right->base.type;
7564         type_t                  *const type_left       = skip_typeref(orig_type_left);
7565         type_t                  *const type_right      = skip_typeref(orig_type_right);
7566         source_position_t const *const pos             = &expression->base.source_position;
7567
7568         /* § 5.6.5 */
7569         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7570                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7571                 expression->left        = create_implicit_cast(left, arithmetic_type);
7572                 expression->right       = create_implicit_cast(right, arithmetic_type);
7573                 expression->base.type =  arithmetic_type;
7574                 return;
7575         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7576                 check_pointer_arithmetic(&expression->base.source_position,
7577                                          type_left, orig_type_left);
7578                 expression->base.type = type_left;
7579         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7580                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
7581                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
7582                 if (!types_compatible(unqual_left, unqual_right)) {
7583                         errorf(pos,
7584                                "subtracting pointers to incompatible types '%T' and '%T'",
7585                                orig_type_left, orig_type_right);
7586                 } else if (!is_type_object(unqual_left)) {
7587                         if (is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
7588                                 warningf(pos, "subtracting pointers to void");
7589                         } else {
7590                                 errorf(pos, "subtracting pointers to non-object types '%T'",
7591                                        orig_type_left);
7592                         }
7593                 }
7594                 expression->base.type = type_ptrdiff_t;
7595         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7596                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
7597                        orig_type_left, orig_type_right);
7598         }
7599 }
7600
7601 /**
7602  * Check the semantics of comparison expressions.
7603  *
7604  * @param expression   The expression to check.
7605  */
7606 static void semantic_comparison(binary_expression_t *expression)
7607 {
7608         expression_t *left            = expression->left;
7609         expression_t *right           = expression->right;
7610         type_t       *orig_type_left  = left->base.type;
7611         type_t       *orig_type_right = right->base.type;
7612
7613         type_t *type_left  = skip_typeref(orig_type_left);
7614         type_t *type_right = skip_typeref(orig_type_right);
7615
7616         /* TODO non-arithmetic types */
7617         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7618                 /* test for signed vs unsigned compares */
7619                 if (warning.sign_compare &&
7620                     (expression->base.kind != EXPR_BINARY_EQUAL &&
7621                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
7622                     (is_type_signed(type_left) != is_type_signed(type_right))) {
7623
7624                         /* check if 1 of the operands is a constant, in this case we just
7625                          * check wether we can safely represent the resulting constant in
7626                          * the type of the other operand. */
7627                         expression_t *const_expr = NULL;
7628                         expression_t *other_expr = NULL;
7629
7630                         if (is_constant_expression(left)) {
7631                                 const_expr = left;
7632                                 other_expr = right;
7633                         } else if (is_constant_expression(right)) {
7634                                 const_expr = right;
7635                                 other_expr = left;
7636                         }
7637
7638                         if (const_expr != NULL) {
7639                                 type_t *other_type = skip_typeref(other_expr->base.type);
7640                                 long    val        = fold_constant(const_expr);
7641                                 /* TODO: check if val can be represented by other_type */
7642                                 (void) other_type;
7643                                 (void) val;
7644                         }
7645                         warningf(&expression->base.source_position,
7646                                  "comparison between signed and unsigned");
7647                 }
7648                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7649                 expression->left        = create_implicit_cast(left, arithmetic_type);
7650                 expression->right       = create_implicit_cast(right, arithmetic_type);
7651                 expression->base.type   = arithmetic_type;
7652                 if (warning.float_equal &&
7653                     (expression->base.kind == EXPR_BINARY_EQUAL ||
7654                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
7655                     is_type_float(arithmetic_type)) {
7656                         warningf(&expression->base.source_position,
7657                                  "comparing floating point with == or != is unsafe");
7658                 }
7659         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7660                 /* TODO check compatibility */
7661         } else if (is_type_pointer(type_left)) {
7662                 expression->right = create_implicit_cast(right, type_left);
7663         } else if (is_type_pointer(type_right)) {
7664                 expression->left = create_implicit_cast(left, type_right);
7665         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7666                 type_error_incompatible("invalid operands in comparison",
7667                                         &expression->base.source_position,
7668                                         type_left, type_right);
7669         }
7670         expression->base.type = type_int;
7671 }
7672
7673 /**
7674  * Checks if a compound type has constant fields.
7675  */
7676 static bool has_const_fields(const compound_type_t *type)
7677 {
7678         const scope_t       *scope       = &type->declaration->scope;
7679         const declaration_t *declaration = scope->declarations;
7680
7681         for (; declaration != NULL; declaration = declaration->next) {
7682                 if (declaration->namespc != NAMESPACE_NORMAL)
7683                         continue;
7684
7685                 const type_t *decl_type = skip_typeref(declaration->type);
7686                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
7687                         return true;
7688         }
7689         /* TODO */
7690         return false;
7691 }
7692
7693 static bool is_valid_assignment_lhs(expression_t const* const left)
7694 {
7695         type_t *const orig_type_left = revert_automatic_type_conversion(left);
7696         type_t *const type_left      = skip_typeref(orig_type_left);
7697
7698         if (!is_lvalue(left)) {
7699                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
7700                        left);
7701                 return false;
7702         }
7703
7704         if (is_type_array(type_left)) {
7705                 errorf(HERE, "cannot assign to arrays ('%E')", left);
7706                 return false;
7707         }
7708         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
7709                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
7710                        orig_type_left);
7711                 return false;
7712         }
7713         if (is_type_incomplete(type_left)) {
7714                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
7715                        left, orig_type_left);
7716                 return false;
7717         }
7718         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
7719                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
7720                        left, orig_type_left);
7721                 return false;
7722         }
7723
7724         return true;
7725 }
7726
7727 static void semantic_arithmetic_assign(binary_expression_t *expression)
7728 {
7729         expression_t *left            = expression->left;
7730         expression_t *right           = expression->right;
7731         type_t       *orig_type_left  = left->base.type;
7732         type_t       *orig_type_right = right->base.type;
7733
7734         if (!is_valid_assignment_lhs(left))
7735                 return;
7736
7737         type_t *type_left  = skip_typeref(orig_type_left);
7738         type_t *type_right = skip_typeref(orig_type_right);
7739
7740         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7741                 /* TODO: improve error message */
7742                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7743                         errorf(&expression->base.source_position,
7744                                "operation needs arithmetic types");
7745                 }
7746                 return;
7747         }
7748
7749         /* combined instructions are tricky. We can't create an implicit cast on
7750          * the left side, because we need the uncasted form for the store.
7751          * The ast2firm pass has to know that left_type must be right_type
7752          * for the arithmetic operation and create a cast by itself */
7753         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7754         expression->right       = create_implicit_cast(right, arithmetic_type);
7755         expression->base.type   = type_left;
7756 }
7757
7758 static void semantic_divmod_assign(binary_expression_t *expression)
7759 {
7760         semantic_arithmetic_assign(expression);
7761         warn_div_by_zero(expression);
7762 }
7763
7764 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
7765 {
7766         expression_t *const left            = expression->left;
7767         expression_t *const right           = expression->right;
7768         type_t       *const orig_type_left  = left->base.type;
7769         type_t       *const orig_type_right = right->base.type;
7770         type_t       *const type_left       = skip_typeref(orig_type_left);
7771         type_t       *const type_right      = skip_typeref(orig_type_right);
7772
7773         if (!is_valid_assignment_lhs(left))
7774                 return;
7775
7776         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7777                 /* combined instructions are tricky. We can't create an implicit cast on
7778                  * the left side, because we need the uncasted form for the store.
7779                  * The ast2firm pass has to know that left_type must be right_type
7780                  * for the arithmetic operation and create a cast by itself */
7781                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
7782                 expression->right     = create_implicit_cast(right, arithmetic_type);
7783                 expression->base.type = type_left;
7784         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7785                 check_pointer_arithmetic(&expression->base.source_position,
7786                                          type_left, orig_type_left);
7787                 expression->base.type = type_left;
7788         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7789                 errorf(&expression->base.source_position,
7790                        "incompatible types '%T' and '%T' in assignment",
7791                        orig_type_left, orig_type_right);
7792         }
7793 }
7794
7795 /**
7796  * Check the semantic restrictions of a logical expression.
7797  */
7798 static void semantic_logical_op(binary_expression_t *expression)
7799 {
7800         expression_t *const left            = expression->left;
7801         expression_t *const right           = expression->right;
7802         type_t       *const orig_type_left  = left->base.type;
7803         type_t       *const orig_type_right = right->base.type;
7804         type_t       *const type_left       = skip_typeref(orig_type_left);
7805         type_t       *const type_right      = skip_typeref(orig_type_right);
7806
7807         if (!is_type_scalar(type_left) || !is_type_scalar(type_right)) {
7808                 /* TODO: improve error message */
7809                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7810                         errorf(&expression->base.source_position,
7811                                "operation needs scalar types");
7812                 }
7813                 return;
7814         }
7815
7816         expression->base.type = type_int;
7817 }
7818
7819 /**
7820  * Check the semantic restrictions of a binary assign expression.
7821  */
7822 static void semantic_binexpr_assign(binary_expression_t *expression)
7823 {
7824         expression_t *left           = expression->left;
7825         type_t       *orig_type_left = left->base.type;
7826
7827         type_t *type_left = revert_automatic_type_conversion(left);
7828         type_left         = skip_typeref(orig_type_left);
7829
7830         if (!is_valid_assignment_lhs(left))
7831                 return;
7832
7833         assign_error_t error = semantic_assign(orig_type_left, expression->right);
7834         report_assign_error(error, orig_type_left, expression->right,
7835                         "assignment", &left->base.source_position);
7836         expression->right = create_implicit_cast(expression->right, orig_type_left);
7837         expression->base.type = orig_type_left;
7838 }
7839
7840 /**
7841  * Determine if the outermost operation (or parts thereof) of the given
7842  * expression has no effect in order to generate a warning about this fact.
7843  * Therefore in some cases this only examines some of the operands of the
7844  * expression (see comments in the function and examples below).
7845  * Examples:
7846  *   f() + 23;    // warning, because + has no effect
7847  *   x || f();    // no warning, because x controls execution of f()
7848  *   x ? y : f(); // warning, because y has no effect
7849  *   (void)x;     // no warning to be able to suppress the warning
7850  * This function can NOT be used for an "expression has definitely no effect"-
7851  * analysis. */
7852 static bool expression_has_effect(const expression_t *const expr)
7853 {
7854         switch (expr->kind) {
7855                 case EXPR_UNKNOWN:                   break;
7856                 case EXPR_INVALID:                   return true; /* do NOT warn */
7857                 case EXPR_REFERENCE:                 return false;
7858                 /* suppress the warning for microsoft __noop operations */
7859                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
7860                 case EXPR_CHARACTER_CONSTANT:        return false;
7861                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
7862                 case EXPR_STRING_LITERAL:            return false;
7863                 case EXPR_WIDE_STRING_LITERAL:       return false;
7864
7865                 case EXPR_CALL: {
7866                         const call_expression_t *const call = &expr->call;
7867                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
7868                                 return true;
7869
7870                         switch (call->function->builtin_symbol.symbol->ID) {
7871                                 case T___builtin_va_end: return true;
7872                                 default:                 return false;
7873                         }
7874                 }
7875
7876                 /* Generate the warning if either the left or right hand side of a
7877                  * conditional expression has no effect */
7878                 case EXPR_CONDITIONAL: {
7879                         const conditional_expression_t *const cond = &expr->conditional;
7880                         return
7881                                 expression_has_effect(cond->true_expression) &&
7882                                 expression_has_effect(cond->false_expression);
7883                 }
7884
7885                 case EXPR_SELECT:                    return false;
7886                 case EXPR_ARRAY_ACCESS:              return false;
7887                 case EXPR_SIZEOF:                    return false;
7888                 case EXPR_CLASSIFY_TYPE:             return false;
7889                 case EXPR_ALIGNOF:                   return false;
7890
7891                 case EXPR_FUNCNAME:                  return false;
7892                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
7893                 case EXPR_BUILTIN_CONSTANT_P:        return false;
7894                 case EXPR_BUILTIN_PREFETCH:          return true;
7895                 case EXPR_OFFSETOF:                  return false;
7896                 case EXPR_VA_START:                  return true;
7897                 case EXPR_VA_ARG:                    return true;
7898                 case EXPR_STATEMENT:                 return true; // TODO
7899                 case EXPR_COMPOUND_LITERAL:          return false;
7900
7901                 case EXPR_UNARY_NEGATE:              return false;
7902                 case EXPR_UNARY_PLUS:                return false;
7903                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
7904                 case EXPR_UNARY_NOT:                 return false;
7905                 case EXPR_UNARY_DEREFERENCE:         return false;
7906                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
7907                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
7908                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
7909                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
7910                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
7911
7912                 /* Treat void casts as if they have an effect in order to being able to
7913                  * suppress the warning */
7914                 case EXPR_UNARY_CAST: {
7915                         type_t *const type = skip_typeref(expr->base.type);
7916                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
7917                 }
7918
7919                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
7920                 case EXPR_UNARY_ASSUME:              return true;
7921
7922                 case EXPR_BINARY_ADD:                return false;
7923                 case EXPR_BINARY_SUB:                return false;
7924                 case EXPR_BINARY_MUL:                return false;
7925                 case EXPR_BINARY_DIV:                return false;
7926                 case EXPR_BINARY_MOD:                return false;
7927                 case EXPR_BINARY_EQUAL:              return false;
7928                 case EXPR_BINARY_NOTEQUAL:           return false;
7929                 case EXPR_BINARY_LESS:               return false;
7930                 case EXPR_BINARY_LESSEQUAL:          return false;
7931                 case EXPR_BINARY_GREATER:            return false;
7932                 case EXPR_BINARY_GREATEREQUAL:       return false;
7933                 case EXPR_BINARY_BITWISE_AND:        return false;
7934                 case EXPR_BINARY_BITWISE_OR:         return false;
7935                 case EXPR_BINARY_BITWISE_XOR:        return false;
7936                 case EXPR_BINARY_SHIFTLEFT:          return false;
7937                 case EXPR_BINARY_SHIFTRIGHT:         return false;
7938                 case EXPR_BINARY_ASSIGN:             return true;
7939                 case EXPR_BINARY_MUL_ASSIGN:         return true;
7940                 case EXPR_BINARY_DIV_ASSIGN:         return true;
7941                 case EXPR_BINARY_MOD_ASSIGN:         return true;
7942                 case EXPR_BINARY_ADD_ASSIGN:         return true;
7943                 case EXPR_BINARY_SUB_ASSIGN:         return true;
7944                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
7945                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
7946                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
7947                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
7948                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
7949
7950                 /* Only examine the right hand side of && and ||, because the left hand
7951                  * side already has the effect of controlling the execution of the right
7952                  * hand side */
7953                 case EXPR_BINARY_LOGICAL_AND:
7954                 case EXPR_BINARY_LOGICAL_OR:
7955                 /* Only examine the right hand side of a comma expression, because the left
7956                  * hand side has a separate warning */
7957                 case EXPR_BINARY_COMMA:
7958                         return expression_has_effect(expr->binary.right);
7959
7960                 case EXPR_BINARY_BUILTIN_EXPECT:     return true;
7961                 case EXPR_BINARY_ISGREATER:          return false;
7962                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
7963                 case EXPR_BINARY_ISLESS:             return false;
7964                 case EXPR_BINARY_ISLESSEQUAL:        return false;
7965                 case EXPR_BINARY_ISLESSGREATER:      return false;
7966                 case EXPR_BINARY_ISUNORDERED:        return false;
7967         }
7968
7969         internal_errorf(HERE, "unexpected expression");
7970 }
7971
7972 static void semantic_comma(binary_expression_t *expression)
7973 {
7974         if (warning.unused_value) {
7975                 const expression_t *const left = expression->left;
7976                 if (!expression_has_effect(left)) {
7977                         warningf(&left->base.source_position,
7978                                  "left-hand operand of comma expression has no effect");
7979                 }
7980         }
7981         expression->base.type = expression->right->base.type;
7982 }
7983
7984 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, sfunc, lr)  \
7985 static expression_t *parse_##binexpression_type(unsigned precedence,      \
7986                                                 expression_t *left)       \
7987 {                                                                         \
7988         expression_t *binexpr = allocate_expression_zero(binexpression_type); \
7989         binexpr->base.source_position = *HERE;                                \
7990         binexpr->binary.left          = left;                                 \
7991         eat(token_type);                                                      \
7992                                                                           \
7993         expression_t *right = parse_sub_expression(precedence + lr);          \
7994                                                                           \
7995         binexpr->binary.right = right;                                        \
7996         sfunc(&binexpr->binary);                                              \
7997                                                                           \
7998         return binexpr;                                                       \
7999 }
8000
8001 CREATE_BINEXPR_PARSER(',', EXPR_BINARY_COMMA,    semantic_comma, 1)
8002 CREATE_BINEXPR_PARSER('*', EXPR_BINARY_MUL,      semantic_binexpr_arithmetic, 1)
8003 CREATE_BINEXPR_PARSER('/', EXPR_BINARY_DIV,      semantic_divmod_arithmetic, 1)
8004 CREATE_BINEXPR_PARSER('%', EXPR_BINARY_MOD,      semantic_divmod_arithmetic, 1)
8005 CREATE_BINEXPR_PARSER('+', EXPR_BINARY_ADD,      semantic_add, 1)
8006 CREATE_BINEXPR_PARSER('-', EXPR_BINARY_SUB,      semantic_sub, 1)
8007 CREATE_BINEXPR_PARSER('<', EXPR_BINARY_LESS,     semantic_comparison, 1)
8008 CREATE_BINEXPR_PARSER('>', EXPR_BINARY_GREATER,  semantic_comparison, 1)
8009 CREATE_BINEXPR_PARSER('=', EXPR_BINARY_ASSIGN,   semantic_binexpr_assign, 0)
8010
8011 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,
8012                       semantic_comparison, 1)
8013 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,
8014                       semantic_comparison, 1)
8015 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,
8016                       semantic_comparison, 1)
8017 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,
8018                       semantic_comparison, 1)
8019
8020 CREATE_BINEXPR_PARSER('&', EXPR_BINARY_BITWISE_AND,
8021                       semantic_binexpr_arithmetic, 1)
8022 CREATE_BINEXPR_PARSER('|', EXPR_BINARY_BITWISE_OR,
8023                       semantic_binexpr_arithmetic, 1)
8024 CREATE_BINEXPR_PARSER('^', EXPR_BINARY_BITWISE_XOR,
8025                       semantic_binexpr_arithmetic, 1)
8026 CREATE_BINEXPR_PARSER(T_ANDAND, EXPR_BINARY_LOGICAL_AND,
8027                       semantic_logical_op, 1)
8028 CREATE_BINEXPR_PARSER(T_PIPEPIPE, EXPR_BINARY_LOGICAL_OR,
8029                       semantic_logical_op, 1)
8030 CREATE_BINEXPR_PARSER(T_LESSLESS, EXPR_BINARY_SHIFTLEFT,
8031                       semantic_shift_op, 1)
8032 CREATE_BINEXPR_PARSER(T_GREATERGREATER, EXPR_BINARY_SHIFTRIGHT,
8033                       semantic_shift_op, 1)
8034 CREATE_BINEXPR_PARSER(T_PLUSEQUAL, EXPR_BINARY_ADD_ASSIGN,
8035                       semantic_arithmetic_addsubb_assign, 0)
8036 CREATE_BINEXPR_PARSER(T_MINUSEQUAL, EXPR_BINARY_SUB_ASSIGN,
8037                       semantic_arithmetic_addsubb_assign, 0)
8038 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL, EXPR_BINARY_MUL_ASSIGN,
8039                       semantic_arithmetic_assign, 0)
8040 CREATE_BINEXPR_PARSER(T_SLASHEQUAL, EXPR_BINARY_DIV_ASSIGN,
8041                       semantic_divmod_assign, 0)
8042 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL, EXPR_BINARY_MOD_ASSIGN,
8043                       semantic_divmod_assign, 0)
8044 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL, EXPR_BINARY_SHIFTLEFT_ASSIGN,
8045                       semantic_arithmetic_assign, 0)
8046 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL, EXPR_BINARY_SHIFTRIGHT_ASSIGN,
8047                       semantic_arithmetic_assign, 0)
8048 CREATE_BINEXPR_PARSER(T_ANDEQUAL, EXPR_BINARY_BITWISE_AND_ASSIGN,
8049                       semantic_arithmetic_assign, 0)
8050 CREATE_BINEXPR_PARSER(T_PIPEEQUAL, EXPR_BINARY_BITWISE_OR_ASSIGN,
8051                       semantic_arithmetic_assign, 0)
8052 CREATE_BINEXPR_PARSER(T_CARETEQUAL, EXPR_BINARY_BITWISE_XOR_ASSIGN,
8053                       semantic_arithmetic_assign, 0)
8054
8055 static expression_t *parse_sub_expression(unsigned precedence)
8056 {
8057         if (token.type < 0) {
8058                 return expected_expression_error();
8059         }
8060
8061         expression_parser_function_t *parser
8062                 = &expression_parsers[token.type];
8063         source_position_t             source_position = token.source_position;
8064         expression_t                 *left;
8065
8066         if (parser->parser != NULL) {
8067                 left = parser->parser(parser->precedence);
8068         } else {
8069                 left = parse_primary_expression();
8070         }
8071         assert(left != NULL);
8072         left->base.source_position = source_position;
8073
8074         while(true) {
8075                 if (token.type < 0) {
8076                         return expected_expression_error();
8077                 }
8078
8079                 parser = &expression_parsers[token.type];
8080                 if (parser->infix_parser == NULL)
8081                         break;
8082                 if (parser->infix_precedence < precedence)
8083                         break;
8084
8085                 left = parser->infix_parser(parser->infix_precedence, left);
8086
8087                 assert(left != NULL);
8088                 assert(left->kind != EXPR_UNKNOWN);
8089                 left->base.source_position = source_position;
8090         }
8091
8092         return left;
8093 }
8094
8095 /**
8096  * Parse an expression.
8097  */
8098 static expression_t *parse_expression(void)
8099 {
8100         return parse_sub_expression(1);
8101 }
8102
8103 /**
8104  * Register a parser for a prefix-like operator with given precedence.
8105  *
8106  * @param parser      the parser function
8107  * @param token_type  the token type of the prefix token
8108  * @param precedence  the precedence of the operator
8109  */
8110 static void register_expression_parser(parse_expression_function parser,
8111                                        int token_type, unsigned precedence)
8112 {
8113         expression_parser_function_t *entry = &expression_parsers[token_type];
8114
8115         if (entry->parser != NULL) {
8116                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
8117                 panic("trying to register multiple expression parsers for a token");
8118         }
8119         entry->parser     = parser;
8120         entry->precedence = precedence;
8121 }
8122
8123 /**
8124  * Register a parser for an infix operator with given precedence.
8125  *
8126  * @param parser      the parser function
8127  * @param token_type  the token type of the infix operator
8128  * @param precedence  the precedence of the operator
8129  */
8130 static void register_infix_parser(parse_expression_infix_function parser,
8131                 int token_type, unsigned precedence)
8132 {
8133         expression_parser_function_t *entry = &expression_parsers[token_type];
8134
8135         if (entry->infix_parser != NULL) {
8136                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
8137                 panic("trying to register multiple infix expression parsers for a "
8138                       "token");
8139         }
8140         entry->infix_parser     = parser;
8141         entry->infix_precedence = precedence;
8142 }
8143
8144 /**
8145  * Initialize the expression parsers.
8146  */
8147 static void init_expression_parsers(void)
8148 {
8149         memset(&expression_parsers, 0, sizeof(expression_parsers));
8150
8151         register_infix_parser(parse_array_expression,         '[',              30);
8152         register_infix_parser(parse_call_expression,          '(',              30);
8153         register_infix_parser(parse_select_expression,        '.',              30);
8154         register_infix_parser(parse_select_expression,        T_MINUSGREATER,   30);
8155         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,
8156                                                               T_PLUSPLUS,       30);
8157         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,
8158                                                               T_MINUSMINUS,     30);
8159
8160         register_infix_parser(parse_EXPR_BINARY_MUL,          '*',              17);
8161         register_infix_parser(parse_EXPR_BINARY_DIV,          '/',              17);
8162         register_infix_parser(parse_EXPR_BINARY_MOD,          '%',              17);
8163         register_infix_parser(parse_EXPR_BINARY_ADD,          '+',              16);
8164         register_infix_parser(parse_EXPR_BINARY_SUB,          '-',              16);
8165         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,    T_LESSLESS,       15);
8166         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,   T_GREATERGREATER, 15);
8167         register_infix_parser(parse_EXPR_BINARY_LESS,         '<',              14);
8168         register_infix_parser(parse_EXPR_BINARY_GREATER,      '>',              14);
8169         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,    T_LESSEQUAL,      14);
8170         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL, T_GREATEREQUAL,   14);
8171         register_infix_parser(parse_EXPR_BINARY_EQUAL,        T_EQUALEQUAL,     13);
8172         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,
8173                                                     T_EXCLAMATIONMARKEQUAL, 13);
8174         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,  '&',              12);
8175         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,  '^',              11);
8176         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,   '|',              10);
8177         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,  T_ANDAND,          9);
8178         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,   T_PIPEPIPE,        8);
8179         register_infix_parser(parse_conditional_expression,   '?',               7);
8180         register_infix_parser(parse_EXPR_BINARY_ASSIGN,       '=',               2);
8181         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,   T_PLUSEQUAL,       2);
8182         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,   T_MINUSEQUAL,      2);
8183         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,   T_ASTERISKEQUAL,   2);
8184         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,   T_SLASHEQUAL,      2);
8185         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,   T_PERCENTEQUAL,    2);
8186         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,
8187                                                                 T_LESSLESSEQUAL, 2);
8188         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,
8189                                                           T_GREATERGREATEREQUAL, 2);
8190         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN,
8191                                                                      T_ANDEQUAL, 2);
8192         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,
8193                                                                     T_PIPEEQUAL, 2);
8194         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN,
8195                                                                    T_CARETEQUAL, 2);
8196
8197         register_infix_parser(parse_EXPR_BINARY_COMMA,        ',',               1);
8198
8199         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-',      25);
8200         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+',      25);
8201         register_expression_parser(parse_EXPR_UNARY_NOT,              '!',      25);
8202         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~',      25);
8203         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*',      25);
8204         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&',      25);
8205         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT,
8206                                                                   T_PLUSPLUS,   25);
8207         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT,
8208                                                                   T_MINUSMINUS, 25);
8209         register_expression_parser(parse_sizeof,                      T_sizeof, 25);
8210         register_expression_parser(parse_alignof,                T___alignof__, 25);
8211         register_expression_parser(parse_extension,            T___extension__, 25);
8212         register_expression_parser(parse_builtin_classify_type,
8213                                                      T___builtin_classify_type, 25);
8214 }
8215
8216 /**
8217  * Parse a asm statement arguments specification.
8218  */
8219 static asm_argument_t *parse_asm_arguments(bool is_out)
8220 {
8221         asm_argument_t *result = NULL;
8222         asm_argument_t *last   = NULL;
8223
8224         while (token.type == T_STRING_LITERAL || token.type == '[') {
8225                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
8226                 memset(argument, 0, sizeof(argument[0]));
8227
8228                 if (token.type == '[') {
8229                         eat('[');
8230                         if (token.type != T_IDENTIFIER) {
8231                                 parse_error_expected("while parsing asm argument",
8232                                                      T_IDENTIFIER, NULL);
8233                                 return NULL;
8234                         }
8235                         argument->symbol = token.v.symbol;
8236
8237                         expect(']');
8238                 }
8239
8240                 argument->constraints = parse_string_literals();
8241                 expect('(');
8242                 add_anchor_token(')');
8243                 expression_t *expression = parse_expression();
8244                 rem_anchor_token(')');
8245                 if (is_out) {
8246                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
8247                          * change size or type representation (e.g. int -> long is ok, but
8248                          * int -> float is not) */
8249                         if (expression->kind == EXPR_UNARY_CAST) {
8250                                 type_t      *const type = expression->base.type;
8251                                 type_kind_t  const kind = type->kind;
8252                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
8253                                         unsigned flags;
8254                                         unsigned size;
8255                                         if (kind == TYPE_ATOMIC) {
8256                                                 atomic_type_kind_t const akind = type->atomic.akind;
8257                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8258                                                 size  = get_atomic_type_size(akind);
8259                                         } else {
8260                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8261                                                 size  = get_atomic_type_size(get_intptr_kind());
8262                                         }
8263
8264                                         do {
8265                                                 expression_t *const value      = expression->unary.value;
8266                                                 type_t       *const value_type = value->base.type;
8267                                                 type_kind_t   const value_kind = value_type->kind;
8268
8269                                                 unsigned value_flags;
8270                                                 unsigned value_size;
8271                                                 if (value_kind == TYPE_ATOMIC) {
8272                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
8273                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8274                                                         value_size  = get_atomic_type_size(value_akind);
8275                                                 } else if (value_kind == TYPE_POINTER) {
8276                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8277                                                         value_size  = get_atomic_type_size(get_intptr_kind());
8278                                                 } else {
8279                                                         break;
8280                                                 }
8281
8282                                                 if (value_flags != flags || value_size != size)
8283                                                         break;
8284
8285                                                 expression = value;
8286                                         } while (expression->kind == EXPR_UNARY_CAST);
8287                                 }
8288                         }
8289
8290                         if (!is_lvalue(expression)) {
8291                                 errorf(&expression->base.source_position,
8292                                        "asm output argument is not an lvalue");
8293                         }
8294                 }
8295                 argument->expression = expression;
8296                 expect(')');
8297
8298                 set_address_taken(expression, true);
8299
8300                 if (last != NULL) {
8301                         last->next = argument;
8302                 } else {
8303                         result = argument;
8304                 }
8305                 last = argument;
8306
8307                 if (token.type != ',')
8308                         break;
8309                 eat(',');
8310         }
8311
8312         return result;
8313 end_error:
8314         return NULL;
8315 }
8316
8317 /**
8318  * Parse a asm statement clobber specification.
8319  */
8320 static asm_clobber_t *parse_asm_clobbers(void)
8321 {
8322         asm_clobber_t *result = NULL;
8323         asm_clobber_t *last   = NULL;
8324
8325         while(token.type == T_STRING_LITERAL) {
8326                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
8327                 clobber->clobber       = parse_string_literals();
8328
8329                 if (last != NULL) {
8330                         last->next = clobber;
8331                 } else {
8332                         result = clobber;
8333                 }
8334                 last = clobber;
8335
8336                 if (token.type != ',')
8337                         break;
8338                 eat(',');
8339         }
8340
8341         return result;
8342 }
8343
8344 /**
8345  * Parse an asm statement.
8346  */
8347 static statement_t *parse_asm_statement(void)
8348 {
8349         eat(T_asm);
8350
8351         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
8352         statement->base.source_position = token.source_position;
8353
8354         asm_statement_t *asm_statement = &statement->asms;
8355
8356         if (token.type == T_volatile) {
8357                 next_token();
8358                 asm_statement->is_volatile = true;
8359         }
8360
8361         expect('(');
8362         add_anchor_token(')');
8363         add_anchor_token(':');
8364         asm_statement->asm_text = parse_string_literals();
8365
8366         if (token.type != ':') {
8367                 rem_anchor_token(':');
8368                 goto end_of_asm;
8369         }
8370         eat(':');
8371
8372         asm_statement->outputs = parse_asm_arguments(true);
8373         if (token.type != ':') {
8374                 rem_anchor_token(':');
8375                 goto end_of_asm;
8376         }
8377         eat(':');
8378
8379         asm_statement->inputs = parse_asm_arguments(false);
8380         if (token.type != ':') {
8381                 rem_anchor_token(':');
8382                 goto end_of_asm;
8383         }
8384         rem_anchor_token(':');
8385         eat(':');
8386
8387         asm_statement->clobbers = parse_asm_clobbers();
8388
8389 end_of_asm:
8390         rem_anchor_token(')');
8391         expect(')');
8392         expect(';');
8393
8394         if (asm_statement->outputs == NULL) {
8395                 /* GCC: An 'asm' instruction without any output operands will be treated
8396                  * identically to a volatile 'asm' instruction. */
8397                 asm_statement->is_volatile = true;
8398         }
8399
8400         return statement;
8401 end_error:
8402         return create_invalid_statement();
8403 }
8404
8405 /**
8406  * Parse a case statement.
8407  */
8408 static statement_t *parse_case_statement(void)
8409 {
8410         eat(T_case);
8411
8412         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8413         source_position_t *const pos       = &statement->base.source_position;
8414
8415         *pos                             = token.source_position;
8416         statement->case_label.expression = parse_expression();
8417         if (! is_constant_expression(statement->case_label.expression)) {
8418                 errorf(pos, "case label does not reduce to an integer constant");
8419                 statement->case_label.is_bad = true;
8420         } else {
8421                 long const val = fold_constant(statement->case_label.expression);
8422                 statement->case_label.first_case = val;
8423                 statement->case_label.last_case  = val;
8424         }
8425
8426         if (c_mode & _GNUC) {
8427                 if (token.type == T_DOTDOTDOT) {
8428                         next_token();
8429                         statement->case_label.end_range = parse_expression();
8430                         if (! is_constant_expression(statement->case_label.end_range)) {
8431                                 errorf(pos, "case range does not reduce to an integer constant");
8432                                 statement->case_label.is_bad = true;
8433                         } else {
8434                                 long const val = fold_constant(statement->case_label.end_range);
8435                                 statement->case_label.last_case = val;
8436
8437                                 if (val < statement->case_label.first_case) {
8438                                         statement->case_label.is_empty = true;
8439                                         warningf(pos, "empty range specified");
8440                                 }
8441                         }
8442                 }
8443         }
8444
8445         PUSH_PARENT(statement);
8446
8447         expect(':');
8448
8449         if (current_switch != NULL) {
8450                 if (! statement->case_label.is_bad) {
8451                         /* Check for duplicate case values */
8452                         case_label_statement_t *c = &statement->case_label;
8453                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
8454                                 if (l->is_bad || l->is_empty || l->expression == NULL)
8455                                         continue;
8456
8457                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
8458                                         continue;
8459
8460                                 errorf(pos, "duplicate case value (previously used %P)",
8461                                        &l->base.source_position);
8462                                 break;
8463                         }
8464                 }
8465                 /* link all cases into the switch statement */
8466                 if (current_switch->last_case == NULL) {
8467                         current_switch->first_case      = &statement->case_label;
8468                 } else {
8469                         current_switch->last_case->next = &statement->case_label;
8470                 }
8471                 current_switch->last_case = &statement->case_label;
8472         } else {
8473                 errorf(pos, "case label not within a switch statement");
8474         }
8475
8476         statement_t *const inner_stmt = parse_statement();
8477         statement->case_label.statement = inner_stmt;
8478         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8479                 errorf(&inner_stmt->base.source_position, "declaration after case label");
8480         }
8481
8482         POP_PARENT;
8483         return statement;
8484 end_error:
8485         POP_PARENT;
8486         return create_invalid_statement();
8487 }
8488
8489 /**
8490  * Parse a default statement.
8491  */
8492 static statement_t *parse_default_statement(void)
8493 {
8494         eat(T_default);
8495
8496         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8497         statement->base.source_position = token.source_position;
8498
8499         PUSH_PARENT(statement);
8500
8501         expect(':');
8502         if (current_switch != NULL) {
8503                 const case_label_statement_t *def_label = current_switch->default_label;
8504                 if (def_label != NULL) {
8505                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
8506                                &def_label->base.source_position);
8507                 } else {
8508                         current_switch->default_label = &statement->case_label;
8509
8510                         /* link all cases into the switch statement */
8511                         if (current_switch->last_case == NULL) {
8512                                 current_switch->first_case      = &statement->case_label;
8513                         } else {
8514                                 current_switch->last_case->next = &statement->case_label;
8515                         }
8516                         current_switch->last_case = &statement->case_label;
8517                 }
8518         } else {
8519                 errorf(&statement->base.source_position,
8520                         "'default' label not within a switch statement");
8521         }
8522
8523         statement_t *const inner_stmt = parse_statement();
8524         statement->case_label.statement = inner_stmt;
8525         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8526                 errorf(&inner_stmt->base.source_position, "declaration after default label");
8527         }
8528
8529         POP_PARENT;
8530         return statement;
8531 end_error:
8532         POP_PARENT;
8533         return create_invalid_statement();
8534 }
8535
8536 /**
8537  * Return the declaration for a given label symbol or create a new one.
8538  *
8539  * @param symbol  the symbol of the label
8540  */
8541 static declaration_t *get_label(symbol_t *symbol)
8542 {
8543         declaration_t *candidate = get_declaration(symbol, NAMESPACE_LABEL);
8544         assert(current_function != NULL);
8545         /* if we found a label in the same function, then we already created the
8546          * declaration */
8547         if (candidate != NULL
8548                         && candidate->parent_scope == &current_function->scope) {
8549                 return candidate;
8550         }
8551
8552         /* otherwise we need to create a new one */
8553         declaration_t *const declaration = allocate_declaration_zero();
8554         declaration->namespc       = NAMESPACE_LABEL;
8555         declaration->symbol        = symbol;
8556
8557         label_push(declaration);
8558
8559         return declaration;
8560 }
8561
8562 /**
8563  * Parse a label statement.
8564  */
8565 static statement_t *parse_label_statement(void)
8566 {
8567         assert(token.type == T_IDENTIFIER);
8568         symbol_t *symbol = token.v.symbol;
8569         next_token();
8570
8571         declaration_t *label = get_label(symbol);
8572
8573         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
8574         statement->base.source_position = token.source_position;
8575         statement->label.label          = label;
8576
8577         PUSH_PARENT(statement);
8578
8579         /* if source position is already set then the label is defined twice,
8580          * otherwise it was just mentioned in a goto so far */
8581         if (label->source_position.input_name != NULL) {
8582                 errorf(HERE, "duplicate label '%Y' (declared %P)",
8583                        symbol, &label->source_position);
8584         } else {
8585                 label->source_position = token.source_position;
8586                 label->init.statement  = statement;
8587         }
8588
8589         eat(':');
8590
8591         if (token.type == '}') {
8592                 /* TODO only warn? */
8593                 if (false) {
8594                         warningf(HERE, "label at end of compound statement");
8595                         statement->label.statement = create_empty_statement();
8596                 } else {
8597                         errorf(HERE, "label at end of compound statement");
8598                         statement->label.statement = create_invalid_statement();
8599                 }
8600         } else if (token.type == ';') {
8601                 /* Eat an empty statement here, to avoid the warning about an empty
8602                  * statement after a label.  label:; is commonly used to have a label
8603                  * before a closing brace. */
8604                 statement->label.statement = create_empty_statement();
8605                 next_token();
8606         } else {
8607                 statement_t *const inner_stmt = parse_statement();
8608                 statement->label.statement = inner_stmt;
8609                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
8610                         errorf(&inner_stmt->base.source_position, "declaration after label");
8611                 }
8612         }
8613
8614         /* remember the labels in a list for later checking */
8615         if (label_last == NULL) {
8616                 label_first = &statement->label;
8617         } else {
8618                 label_last->next = &statement->label;
8619         }
8620         label_last = &statement->label;
8621
8622         POP_PARENT;
8623         return statement;
8624 }
8625
8626 /**
8627  * Parse an if statement.
8628  */
8629 static statement_t *parse_if(void)
8630 {
8631         eat(T_if);
8632
8633         statement_t *statement          = allocate_statement_zero(STATEMENT_IF);
8634         statement->base.source_position = token.source_position;
8635
8636         PUSH_PARENT(statement);
8637
8638         expect('(');
8639         add_anchor_token(')');
8640         statement->ifs.condition = parse_expression();
8641         rem_anchor_token(')');
8642         expect(')');
8643
8644         add_anchor_token(T_else);
8645         statement->ifs.true_statement = parse_statement();
8646         rem_anchor_token(T_else);
8647
8648         if (token.type == T_else) {
8649                 next_token();
8650                 statement->ifs.false_statement = parse_statement();
8651         }
8652
8653         POP_PARENT;
8654         return statement;
8655 end_error:
8656         POP_PARENT;
8657         return create_invalid_statement();
8658 }
8659
8660 /**
8661  * Check that all enums are handled in a switch.
8662  *
8663  * @param statement  the switch statement to check
8664  */
8665 static void check_enum_cases(const switch_statement_t *statement) {
8666         const type_t *type = skip_typeref(statement->expression->base.type);
8667         if (! is_type_enum(type))
8668                 return;
8669         const enum_type_t *enumt = &type->enumt;
8670
8671         /* if we have a default, no warnings */
8672         if (statement->default_label != NULL)
8673                 return;
8674
8675         /* FIXME: calculation of value should be done while parsing */
8676         const declaration_t *declaration;
8677         long last_value = -1;
8678         for (declaration = enumt->declaration->next;
8679              declaration != NULL && declaration->storage_class == STORAGE_CLASS_ENUM_ENTRY;
8680                  declaration = declaration->next) {
8681                 const expression_t *expression = declaration->init.enum_value;
8682                 long                value      = expression != NULL ? fold_constant(expression) : last_value + 1;
8683                 bool                found      = false;
8684                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
8685                         if (l->expression == NULL)
8686                                 continue;
8687                         if (l->first_case <= value && value <= l->last_case) {
8688                                 found = true;
8689                                 break;
8690                         }
8691                 }
8692                 if (! found) {
8693                         warningf(&statement->base.source_position,
8694                                 "enumeration value '%Y' not handled in switch", declaration->symbol);
8695                 }
8696                 last_value = value;
8697         }
8698 }
8699
8700 /**
8701  * Parse a switch statement.
8702  */
8703 static statement_t *parse_switch(void)
8704 {
8705         eat(T_switch);
8706
8707         statement_t *statement          = allocate_statement_zero(STATEMENT_SWITCH);
8708         statement->base.source_position = token.source_position;
8709
8710         PUSH_PARENT(statement);
8711
8712         expect('(');
8713         add_anchor_token(')');
8714         expression_t *const expr = parse_expression();
8715         type_t       *      type = skip_typeref(expr->base.type);
8716         if (is_type_integer(type)) {
8717                 type = promote_integer(type);
8718                 if (warning.traditional) {
8719                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
8720                                 warningf(&expr->base.source_position,
8721                                         "'%T' switch expression not converted to '%T' in ISO C",
8722                                         type, type_int);
8723                         }
8724                 }
8725         } else if (is_type_valid(type)) {
8726                 errorf(&expr->base.source_position,
8727                        "switch quantity is not an integer, but '%T'", type);
8728                 type = type_error_type;
8729         }
8730         statement->switchs.expression = create_implicit_cast(expr, type);
8731         expect(')');
8732         rem_anchor_token(')');
8733
8734         switch_statement_t *rem = current_switch;
8735         current_switch          = &statement->switchs;
8736         statement->switchs.body = parse_statement();
8737         current_switch          = rem;
8738
8739         if (warning.switch_default &&
8740             statement->switchs.default_label == NULL) {
8741                 warningf(&statement->base.source_position, "switch has no default case");
8742         }
8743         if (warning.switch_enum)
8744                 check_enum_cases(&statement->switchs);
8745
8746         POP_PARENT;
8747         return statement;
8748 end_error:
8749         POP_PARENT;
8750         return create_invalid_statement();
8751 }
8752
8753 static statement_t *parse_loop_body(statement_t *const loop)
8754 {
8755         statement_t *const rem = current_loop;
8756         current_loop = loop;
8757
8758         statement_t *const body = parse_statement();
8759
8760         current_loop = rem;
8761         return body;
8762 }
8763
8764 /**
8765  * Parse a while statement.
8766  */
8767 static statement_t *parse_while(void)
8768 {
8769         eat(T_while);
8770
8771         statement_t *statement          = allocate_statement_zero(STATEMENT_WHILE);
8772         statement->base.source_position = token.source_position;
8773
8774         PUSH_PARENT(statement);
8775
8776         expect('(');
8777         add_anchor_token(')');
8778         statement->whiles.condition = parse_expression();
8779         rem_anchor_token(')');
8780         expect(')');
8781
8782         statement->whiles.body = parse_loop_body(statement);
8783
8784         POP_PARENT;
8785         return statement;
8786 end_error:
8787         POP_PARENT;
8788         return create_invalid_statement();
8789 }
8790
8791 /**
8792  * Parse a do statement.
8793  */
8794 static statement_t *parse_do(void)
8795 {
8796         eat(T_do);
8797
8798         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
8799         statement->base.source_position = token.source_position;
8800
8801         PUSH_PARENT(statement)
8802
8803         add_anchor_token(T_while);
8804         statement->do_while.body = parse_loop_body(statement);
8805         rem_anchor_token(T_while);
8806
8807         expect(T_while);
8808         expect('(');
8809         add_anchor_token(')');
8810         statement->do_while.condition = parse_expression();
8811         rem_anchor_token(')');
8812         expect(')');
8813         expect(';');
8814
8815         POP_PARENT;
8816         return statement;
8817 end_error:
8818         POP_PARENT;
8819         return create_invalid_statement();
8820 }
8821
8822 /**
8823  * Parse a for statement.
8824  */
8825 static statement_t *parse_for(void)
8826 {
8827         eat(T_for);
8828
8829         statement_t *statement          = allocate_statement_zero(STATEMENT_FOR);
8830         statement->base.source_position = token.source_position;
8831
8832         PUSH_PARENT(statement);
8833
8834         int      top        = environment_top();
8835         scope_t *last_scope = scope;
8836         set_scope(&statement->fors.scope);
8837
8838         expect('(');
8839         add_anchor_token(')');
8840
8841         if (token.type != ';') {
8842                 if (is_declaration_specifier(&token, false)) {
8843                         parse_declaration(record_declaration);
8844                 } else {
8845                         add_anchor_token(';');
8846                         expression_t *const init = parse_expression();
8847                         statement->fors.initialisation = init;
8848                         if (warning.unused_value && !expression_has_effect(init)) {
8849                                 warningf(&init->base.source_position,
8850                                          "initialisation of 'for'-statement has no effect");
8851                         }
8852                         rem_anchor_token(';');
8853                         expect(';');
8854                 }
8855         } else {
8856                 expect(';');
8857         }
8858
8859         if (token.type != ';') {
8860                 add_anchor_token(';');
8861                 statement->fors.condition = parse_expression();
8862                 rem_anchor_token(';');
8863         }
8864         expect(';');
8865         if (token.type != ')') {
8866                 expression_t *const step = parse_expression();
8867                 statement->fors.step = step;
8868                 if (warning.unused_value && !expression_has_effect(step)) {
8869                         warningf(&step->base.source_position,
8870                                  "step of 'for'-statement has no effect");
8871                 }
8872         }
8873         rem_anchor_token(')');
8874         expect(')');
8875         statement->fors.body = parse_loop_body(statement);
8876
8877         assert(scope == &statement->fors.scope);
8878         set_scope(last_scope);
8879         environment_pop_to(top);
8880
8881         POP_PARENT;
8882         return statement;
8883
8884 end_error:
8885         POP_PARENT;
8886         rem_anchor_token(')');
8887         assert(scope == &statement->fors.scope);
8888         set_scope(last_scope);
8889         environment_pop_to(top);
8890
8891         return create_invalid_statement();
8892 }
8893
8894 /**
8895  * Parse a goto statement.
8896  */
8897 static statement_t *parse_goto(void)
8898 {
8899         eat(T_goto);
8900
8901         if (token.type != T_IDENTIFIER) {
8902                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
8903                 eat_statement();
8904                 goto end_error;
8905         }
8906         symbol_t *symbol = token.v.symbol;
8907         next_token();
8908
8909         declaration_t *label = get_label(symbol);
8910
8911         statement_t *statement          = allocate_statement_zero(STATEMENT_GOTO);
8912         statement->base.source_position = token.source_position;
8913
8914         statement->gotos.label = label;
8915
8916         /* remember the goto's in a list for later checking */
8917         if (goto_last == NULL) {
8918                 goto_first = &statement->gotos;
8919         } else {
8920                 goto_last->next = &statement->gotos;
8921         }
8922         goto_last = &statement->gotos;
8923
8924         expect(';');
8925
8926         return statement;
8927 end_error:
8928         return create_invalid_statement();
8929 }
8930
8931 /**
8932  * Parse a continue statement.
8933  */
8934 static statement_t *parse_continue(void)
8935 {
8936         if (current_loop == NULL) {
8937                 errorf(HERE, "continue statement not within loop");
8938         }
8939
8940         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
8941         statement->base.source_position = token.source_position;
8942
8943         eat(T_continue);
8944         expect(';');
8945
8946 end_error:
8947         return statement;
8948 }
8949
8950 /**
8951  * Parse a break statement.
8952  */
8953 static statement_t *parse_break(void)
8954 {
8955         if (current_switch == NULL && current_loop == NULL) {
8956                 errorf(HERE, "break statement not within loop or switch");
8957         }
8958
8959         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
8960         statement->base.source_position = token.source_position;
8961
8962         eat(T_break);
8963         expect(';');
8964
8965 end_error:
8966         return statement;
8967 }
8968
8969 /**
8970  * Parse a __leave statement.
8971  */
8972 static statement_t *parse_leave(void)
8973 {
8974         if (current_try == NULL) {
8975                 errorf(HERE, "__leave statement not within __try");
8976         }
8977
8978         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
8979         statement->base.source_position = token.source_position;
8980
8981         eat(T___leave);
8982         expect(';');
8983
8984 end_error:
8985         return statement;
8986 }
8987
8988 /**
8989  * Check if a given declaration represents a local variable.
8990  */
8991 static bool is_local_var_declaration(const declaration_t *declaration)
8992 {
8993         switch ((storage_class_tag_t) declaration->storage_class) {
8994         case STORAGE_CLASS_AUTO:
8995         case STORAGE_CLASS_REGISTER: {
8996                 const type_t *type = skip_typeref(declaration->type);
8997                 if (is_type_function(type)) {
8998                         return false;
8999                 } else {
9000                         return true;
9001                 }
9002         }
9003         default:
9004                 return false;
9005         }
9006 }
9007
9008 /**
9009  * Check if a given declaration represents a variable.
9010  */
9011 static bool is_var_declaration(const declaration_t *declaration)
9012 {
9013         if (declaration->storage_class == STORAGE_CLASS_TYPEDEF)
9014                 return false;
9015
9016         const type_t *type = skip_typeref(declaration->type);
9017         return !is_type_function(type);
9018 }
9019
9020 /**
9021  * Check if a given expression represents a local variable.
9022  */
9023 static bool is_local_variable(const expression_t *expression)
9024 {
9025         if (expression->base.kind != EXPR_REFERENCE) {
9026                 return false;
9027         }
9028         const declaration_t *declaration = expression->reference.declaration;
9029         return is_local_var_declaration(declaration);
9030 }
9031
9032 /**
9033  * Check if a given expression represents a local variable and
9034  * return its declaration then, else return NULL.
9035  */
9036 declaration_t *expr_is_variable(const expression_t *expression)
9037 {
9038         if (expression->base.kind != EXPR_REFERENCE) {
9039                 return NULL;
9040         }
9041         declaration_t *declaration = expression->reference.declaration;
9042         if (is_var_declaration(declaration))
9043                 return declaration;
9044         return NULL;
9045 }
9046
9047 /**
9048  * Parse a return statement.
9049  */
9050 static statement_t *parse_return(void)
9051 {
9052         statement_t *statement          = allocate_statement_zero(STATEMENT_RETURN);
9053         statement->base.source_position = token.source_position;
9054
9055         eat(T_return);
9056
9057         expression_t *return_value = NULL;
9058         if (token.type != ';') {
9059                 return_value = parse_expression();
9060         }
9061
9062         const type_t *const func_type = current_function->type;
9063         assert(is_type_function(func_type));
9064         type_t *const return_type = skip_typeref(func_type->function.return_type);
9065
9066         if (return_value != NULL) {
9067                 type_t *return_value_type = skip_typeref(return_value->base.type);
9068
9069                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)
9070                                 && !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
9071                         warningf(&statement->base.source_position,
9072                                  "'return' with a value, in function returning void");
9073                         return_value = NULL;
9074                 } else {
9075                         assign_error_t error = semantic_assign(return_type, return_value);
9076                         report_assign_error(error, return_type, return_value, "'return'",
9077                                             &statement->base.source_position);
9078                         return_value = create_implicit_cast(return_value, return_type);
9079                 }
9080                 /* check for returning address of a local var */
9081                 if (return_value != NULL &&
9082                                 return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
9083                         const expression_t *expression = return_value->unary.value;
9084                         if (is_local_variable(expression)) {
9085                                 warningf(&statement->base.source_position,
9086                                          "function returns address of local variable");
9087                         }
9088                 }
9089         } else {
9090                 if (!is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
9091                         warningf(&statement->base.source_position,
9092                                  "'return' without value, in function returning non-void");
9093                 }
9094         }
9095         statement->returns.value = return_value;
9096
9097         expect(';');
9098
9099 end_error:
9100         return statement;
9101 }
9102
9103 /**
9104  * Parse a declaration statement.
9105  */
9106 static statement_t *parse_declaration_statement(void)
9107 {
9108         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
9109
9110         statement->base.source_position = token.source_position;
9111
9112         declaration_t *before = last_declaration;
9113         parse_declaration(record_declaration);
9114
9115         if (before == NULL) {
9116                 statement->declaration.declarations_begin = scope->declarations;
9117         } else {
9118                 statement->declaration.declarations_begin = before->next;
9119         }
9120         statement->declaration.declarations_end = last_declaration;
9121
9122         return statement;
9123 }
9124
9125 /**
9126  * Parse an expression statement, ie. expr ';'.
9127  */
9128 static statement_t *parse_expression_statement(void)
9129 {
9130         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
9131
9132         statement->base.source_position  = token.source_position;
9133         expression_t *const expr         = parse_expression();
9134         statement->expression.expression = expr;
9135
9136         expect(';');
9137
9138 end_error:
9139         return statement;
9140 }
9141
9142 /**
9143  * Parse a microsoft __try { } __finally { } or
9144  * __try{ } __except() { }
9145  */
9146 static statement_t *parse_ms_try_statment(void)
9147 {
9148         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
9149         statement->base.source_position  = token.source_position;
9150         eat(T___try);
9151
9152         PUSH_PARENT(statement);
9153
9154         ms_try_statement_t *rem = current_try;
9155         current_try = &statement->ms_try;
9156         statement->ms_try.try_statement = parse_compound_statement(false);
9157         current_try = rem;
9158
9159         POP_PARENT;
9160
9161         if (token.type == T___except) {
9162                 eat(T___except);
9163                 expect('(');
9164                 add_anchor_token(')');
9165                 expression_t *const expr = parse_expression();
9166                 type_t       *      type = skip_typeref(expr->base.type);
9167                 if (is_type_integer(type)) {
9168                         type = promote_integer(type);
9169                 } else if (is_type_valid(type)) {
9170                         errorf(&expr->base.source_position,
9171                                "__expect expression is not an integer, but '%T'", type);
9172                         type = type_error_type;
9173                 }
9174                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
9175                 rem_anchor_token(')');
9176                 expect(')');
9177                 statement->ms_try.final_statement = parse_compound_statement(false);
9178         } else if (token.type == T__finally) {
9179                 eat(T___finally);
9180                 statement->ms_try.final_statement = parse_compound_statement(false);
9181         } else {
9182                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
9183                 return create_invalid_statement();
9184         }
9185         return statement;
9186 end_error:
9187         return create_invalid_statement();
9188 }
9189
9190 static statement_t *parse_empty_statement(void)
9191 {
9192         if (warning.empty_statement) {
9193                 warningf(HERE, "statement is empty");
9194         }
9195         statement_t *const statement = create_empty_statement();
9196         eat(';');
9197         return statement;
9198 }
9199
9200 /**
9201  * Parse a statement.
9202  * There's also parse_statement() which additionally checks for
9203  * "statement has no effect" warnings
9204  */
9205 static statement_t *intern_parse_statement(void)
9206 {
9207         statement_t *statement = NULL;
9208
9209         /* declaration or statement */
9210         add_anchor_token(';');
9211         switch (token.type) {
9212         case T_IDENTIFIER: {
9213                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
9214                 if (la1_type == ':') {
9215                         statement = parse_label_statement();
9216                 } else if (is_typedef_symbol(token.v.symbol)) {
9217                         statement = parse_declaration_statement();
9218                 } else switch (la1_type) {
9219                         DECLARATION_START
9220                         case T_IDENTIFIER:
9221                         case '*':
9222                                 statement = parse_declaration_statement();
9223                                 break;
9224
9225                         default:
9226                                 statement = parse_expression_statement();
9227                                 break;
9228                 }
9229                 break;
9230         }
9231
9232         case T___extension__:
9233                 /* This can be a prefix to a declaration or an expression statement.
9234                  * We simply eat it now and parse the rest with tail recursion. */
9235                 do {
9236                         next_token();
9237                 } while (token.type == T___extension__);
9238                 statement = parse_statement();
9239                 break;
9240
9241         DECLARATION_START
9242                 statement = parse_declaration_statement();
9243                 break;
9244
9245         case ';':        statement = parse_empty_statement();         break;
9246         case '{':        statement = parse_compound_statement(false); break;
9247         case T___leave:  statement = parse_leave();                   break;
9248         case T___try:    statement = parse_ms_try_statment();         break;
9249         case T_asm:      statement = parse_asm_statement();           break;
9250         case T_break:    statement = parse_break();                   break;
9251         case T_case:     statement = parse_case_statement();          break;
9252         case T_continue: statement = parse_continue();                break;
9253         case T_default:  statement = parse_default_statement();       break;
9254         case T_do:       statement = parse_do();                      break;
9255         case T_for:      statement = parse_for();                     break;
9256         case T_goto:     statement = parse_goto();                    break;
9257         case T_if:       statement = parse_if ();                     break;
9258         case T_return:   statement = parse_return();                  break;
9259         case T_switch:   statement = parse_switch();                  break;
9260         case T_while:    statement = parse_while();                   break;
9261         default:         statement = parse_expression_statement();    break;
9262         }
9263         rem_anchor_token(';');
9264
9265         assert(statement != NULL
9266                         && statement->base.source_position.input_name != NULL);
9267
9268         return statement;
9269 }
9270
9271 /**
9272  * parse a statement and emits "statement has no effect" warning if needed
9273  * (This is really a wrapper around intern_parse_statement with check for 1
9274  *  single warning. It is needed, because for statement expressions we have
9275  *  to avoid the warning on the last statement)
9276  */
9277 static statement_t *parse_statement(void)
9278 {
9279         statement_t *statement = intern_parse_statement();
9280
9281         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
9282                 expression_t *expression = statement->expression.expression;
9283                 if (!expression_has_effect(expression)) {
9284                         warningf(&expression->base.source_position,
9285                                         "statement has no effect");
9286                 }
9287         }
9288
9289         return statement;
9290 }
9291
9292 /**
9293  * Parse a compound statement.
9294  */
9295 static statement_t *parse_compound_statement(bool inside_expression_statement)
9296 {
9297         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
9298         statement->base.source_position = token.source_position;
9299
9300         PUSH_PARENT(statement);
9301
9302         eat('{');
9303         add_anchor_token('}');
9304
9305         int      top        = environment_top();
9306         scope_t *last_scope = scope;
9307         set_scope(&statement->compound.scope);
9308
9309         statement_t **anchor            = &statement->compound.statements;
9310         bool          only_decls_so_far = true;
9311         while (token.type != '}' && token.type != T_EOF) {
9312                 statement_t *sub_statement = intern_parse_statement();
9313                 if (is_invalid_statement(sub_statement)) {
9314                         /* an error occurred. if we are at an anchor, return */
9315                         if (at_anchor())
9316                                 goto end_error;
9317                         continue;
9318                 }
9319
9320                 if (warning.declaration_after_statement) {
9321                         if (sub_statement->kind != STATEMENT_DECLARATION) {
9322                                 only_decls_so_far = false;
9323                         } else if (!only_decls_so_far) {
9324                                 warningf(&sub_statement->base.source_position,
9325                                          "ISO C90 forbids mixed declarations and code");
9326                         }
9327                 }
9328
9329                 *anchor = sub_statement;
9330
9331                 while (sub_statement->base.next != NULL)
9332                         sub_statement = sub_statement->base.next;
9333
9334                 anchor = &sub_statement->base.next;
9335         }
9336
9337         if (token.type == '}') {
9338                 next_token();
9339         } else {
9340                 errorf(&statement->base.source_position,
9341                        "end of file while looking for closing '}'");
9342         }
9343
9344         /* look over all statements again to produce no effect warnings */
9345         if (warning.unused_value) {
9346                 statement_t *sub_statement = statement->compound.statements;
9347                 for( ; sub_statement != NULL; sub_statement = sub_statement->base.next) {
9348                         if (sub_statement->kind != STATEMENT_EXPRESSION)
9349                                 continue;
9350                         /* don't emit a warning for the last expression in an expression
9351                          * statement as it has always an effect */
9352                         if (inside_expression_statement && sub_statement->base.next == NULL)
9353                                 continue;
9354
9355                         expression_t *expression = sub_statement->expression.expression;
9356                         if (!expression_has_effect(expression)) {
9357                                 warningf(&expression->base.source_position,
9358                                          "statement has no effect");
9359                         }
9360                 }
9361         }
9362
9363 end_error:
9364         rem_anchor_token('}');
9365         assert(scope == &statement->compound.scope);
9366         set_scope(last_scope);
9367         environment_pop_to(top);
9368
9369         POP_PARENT;
9370         return statement;
9371 }
9372
9373 /**
9374  * Initialize builtin types.
9375  */
9376 static void initialize_builtin_types(void)
9377 {
9378         type_intmax_t    = make_global_typedef("__intmax_t__",      type_long_long);
9379         type_size_t      = make_global_typedef("__SIZE_TYPE__",     type_unsigned_long);
9380         type_ssize_t     = make_global_typedef("__SSIZE_TYPE__",    type_long);
9381         type_ptrdiff_t   = make_global_typedef("__PTRDIFF_TYPE__",  type_long);
9382         type_uintmax_t   = make_global_typedef("__uintmax_t__",     type_unsigned_long_long);
9383         type_uptrdiff_t  = make_global_typedef("__UPTRDIFF_TYPE__", type_unsigned_long);
9384         type_wchar_t     = make_global_typedef("__WCHAR_TYPE__",    opt_short_wchar_t ? type_unsigned_short : type_int);
9385         type_wint_t      = make_global_typedef("__WINT_TYPE__",     type_int);
9386
9387         type_intmax_t_ptr  = make_pointer_type(type_intmax_t,  TYPE_QUALIFIER_NONE);
9388         type_ptrdiff_t_ptr = make_pointer_type(type_ptrdiff_t, TYPE_QUALIFIER_NONE);
9389         type_ssize_t_ptr   = make_pointer_type(type_ssize_t,   TYPE_QUALIFIER_NONE);
9390         type_wchar_t_ptr   = make_pointer_type(type_wchar_t,   TYPE_QUALIFIER_NONE);
9391
9392         /* const version of wchar_t */
9393         type_const_wchar_t = allocate_type_zero(TYPE_TYPEDEF, &builtin_source_position);
9394         type_const_wchar_t->typedeft.declaration  = type_wchar_t->typedeft.declaration;
9395         type_const_wchar_t->base.qualifiers      |= TYPE_QUALIFIER_CONST;
9396
9397         type_const_wchar_t_ptr = make_pointer_type(type_const_wchar_t, TYPE_QUALIFIER_NONE);
9398 }
9399
9400 /**
9401  * Check for unused global static functions and variables
9402  */
9403 static void check_unused_globals(void)
9404 {
9405         if (!warning.unused_function && !warning.unused_variable)
9406                 return;
9407
9408         for (const declaration_t *decl = global_scope->declarations; decl != NULL; decl = decl->next) {
9409                 if (decl->used                  ||
9410                     decl->modifiers & DM_UNUSED ||
9411                     decl->modifiers & DM_USED   ||
9412                     decl->storage_class != STORAGE_CLASS_STATIC)
9413                         continue;
9414
9415                 type_t *const type = decl->type;
9416                 const char *s;
9417                 if (is_type_function(skip_typeref(type))) {
9418                         if (!warning.unused_function || decl->is_inline)
9419                                 continue;
9420
9421                         s = (decl->init.statement != NULL ? "defined" : "declared");
9422                 } else {
9423                         if (!warning.unused_variable)
9424                                 continue;
9425
9426                         s = "defined";
9427                 }
9428
9429                 warningf(&decl->source_position, "'%#T' %s but not used",
9430                         type, decl->symbol, s);
9431         }
9432 }
9433
9434 static void parse_global_asm(void)
9435 {
9436         eat(T_asm);
9437         expect('(');
9438
9439         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
9440         statement->base.source_position = token.source_position;
9441         statement->asms.asm_text        = parse_string_literals();
9442         statement->base.next            = unit->global_asm;
9443         unit->global_asm                = statement;
9444
9445         expect(')');
9446         expect(';');
9447
9448 end_error:;
9449 }
9450
9451 /**
9452  * Parse a translation unit.
9453  */
9454 static void parse_translation_unit(void)
9455 {
9456         for (;;) switch (token.type) {
9457                 DECLARATION_START
9458                 case T_IDENTIFIER:
9459                 case T___extension__:
9460                         parse_external_declaration();
9461                         break;
9462
9463                 case T_asm:
9464                         parse_global_asm();
9465                         break;
9466
9467                 case T_EOF:
9468                         return;
9469
9470                 case ';':
9471                         /* TODO error in strict mode */
9472                         warningf(HERE, "stray ';' outside of function");
9473                         next_token();
9474                         break;
9475
9476                 default:
9477                         errorf(HERE, "stray %K outside of function", &token);
9478                         if (token.type == '(' || token.type == '{' || token.type == '[')
9479                                 eat_until_matching_token(token.type);
9480                         next_token();
9481                         break;
9482         }
9483 }
9484
9485 /**
9486  * Parse the input.
9487  *
9488  * @return  the translation unit or NULL if errors occurred.
9489  */
9490 void start_parsing(void)
9491 {
9492         environment_stack = NEW_ARR_F(stack_entry_t, 0);
9493         label_stack       = NEW_ARR_F(stack_entry_t, 0);
9494         diagnostic_count  = 0;
9495         error_count       = 0;
9496         warning_count     = 0;
9497
9498         type_set_output(stderr);
9499         ast_set_output(stderr);
9500
9501         assert(unit == NULL);
9502         unit = allocate_ast_zero(sizeof(unit[0]));
9503
9504         assert(global_scope == NULL);
9505         global_scope = &unit->scope;
9506
9507         assert(scope == NULL);
9508         set_scope(&unit->scope);
9509
9510         initialize_builtin_types();
9511 }
9512
9513 translation_unit_t *finish_parsing(void)
9514 {
9515         assert(scope == &unit->scope);
9516         scope          = NULL;
9517         last_declaration = NULL;
9518
9519         assert(global_scope == &unit->scope);
9520         check_unused_globals();
9521         global_scope = NULL;
9522
9523         DEL_ARR_F(environment_stack);
9524         DEL_ARR_F(label_stack);
9525
9526         translation_unit_t *result = unit;
9527         unit = NULL;
9528         return result;
9529 }
9530
9531 void parse(void)
9532 {
9533         lookahead_bufpos = 0;
9534         for(int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
9535                 next_token();
9536         }
9537         parse_translation_unit();
9538 }
9539
9540 /**
9541  * Initialize the parser.
9542  */
9543 void init_parser(void)
9544 {
9545         if (c_mode & _MS) {
9546                 /* add predefined symbols for extended-decl-modifier */
9547                 sym_align      = symbol_table_insert("align");
9548                 sym_allocate   = symbol_table_insert("allocate");
9549                 sym_dllimport  = symbol_table_insert("dllimport");
9550                 sym_dllexport  = symbol_table_insert("dllexport");
9551                 sym_naked      = symbol_table_insert("naked");
9552                 sym_noinline   = symbol_table_insert("noinline");
9553                 sym_noreturn   = symbol_table_insert("noreturn");
9554                 sym_nothrow    = symbol_table_insert("nothrow");
9555                 sym_novtable   = symbol_table_insert("novtable");
9556                 sym_property   = symbol_table_insert("property");
9557                 sym_get        = symbol_table_insert("get");
9558                 sym_put        = symbol_table_insert("put");
9559                 sym_selectany  = symbol_table_insert("selectany");
9560                 sym_thread     = symbol_table_insert("thread");
9561                 sym_uuid       = symbol_table_insert("uuid");
9562                 sym_deprecated = symbol_table_insert("deprecated");
9563                 sym_restrict   = symbol_table_insert("restrict");
9564                 sym_noalias    = symbol_table_insert("noalias");
9565         }
9566         memset(token_anchor_set, 0, sizeof(token_anchor_set));
9567
9568         init_expression_parsers();
9569         obstack_init(&temp_obst);
9570
9571         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
9572         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
9573 }
9574
9575 /**
9576  * Terminate the parser.
9577  */
9578 void exit_parser(void)
9579 {
9580         obstack_free(&temp_obst, NULL);
9581 }