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 "walk_statements.h"
  38 #include "warning.h"
  39 #include "adt/bitfiddle.h"
  40 #include "adt/error.h"
  41 #include "adt/array.h"
  42
  43 /** if wchar_t is equal to unsigned short. */
  44 bool opt_short_wchar_t =
  45 #ifdef _WIN32
  46         true;
  47 #else
  48         false;
  49 #endif
  50
  51 //#define PRINT_TOKENS
  52 #define MAX_LOOKAHEAD 2
  53
  54 typedef struct {
  55         declaration_t *old_declaration;
  56         symbol_t      *symbol;
  57         unsigned short namespc;
  58 } stack_entry_t;
  59
  60 typedef struct argument_list_t argument_list_t;
  61 struct argument_list_t {
  62         long              argument;
  63         argument_list_t  *next;
  64 };
  65
  66 typedef struct gnu_attribute_t gnu_attribute_t;
  67 struct gnu_attribute_t {
  68         gnu_attribute_kind_t kind;           /**< The kind of the GNU attribute. */
  69         gnu_attribute_t     *next;
  70         bool                 invalid;        /**< Set if this attribute had argument errors, */
  71         bool                 have_arguments; /**< True, if this attribute has arguments. */
  72         union {
  73                 size_t              value;
  74                 string_t            string;
  75                 atomic_type_kind_t  akind;
  76                 long                argument;  /**< Single argument. */
  77                 argument_list_t    *arguments; /**< List of argument expressions. */
  78         } u;
  79 };
  80
  81 typedef struct declaration_specifiers_t  declaration_specifiers_t;
  82 struct declaration_specifiers_t {
  83         source_position_t  source_position;
  84         unsigned char      declared_storage_class;
  85         unsigned char      alignment;         /**< Alignment, 0 if not set. */
  86         unsigned int       is_inline : 1;
  87         unsigned int       deprecated : 1;
  88         decl_modifiers_t   modifiers;         /**< declaration modifiers */
  89         gnu_attribute_t   *gnu_attributes;    /**< list of GNU attributes */
  90         const char        *deprecated_string; /**< can be set if declaration was marked deprecated. */
  91         symbol_t          *get_property_sym;  /**< the name of the get property if set. */
  92         symbol_t          *put_property_sym;  /**< the name of the put property if set. */
  93         type_t            *type;
  94 };
  95
  96 /**
  97  * An environment for parsing initializers (and compound literals).
  98  */
  99 typedef struct parse_initializer_env_t {
 100         type_t        *type;        /**< the type of the initializer. In case of an
 101                                          array type with unspecified size this gets
 102                                          adjusted to the actual size. */
 103         declaration_t *declaration; /**< the declaration that is initialized if any */
 104         bool           must_be_constant;
 105 } parse_initializer_env_t;
 106
 107 typedef declaration_t* (*parsed_declaration_func) (declaration_t *declaration, bool is_definition);
 108
 109 /** The current token. */
 110 static token_t             token;
 111 /** The lookahead ring-buffer. */
 112 static token_t             lookahead_buffer[MAX_LOOKAHEAD];
 113 /** Position of the next token in the lookahead buffer. */
 114 static int                 lookahead_bufpos;
 115 static stack_entry_t      *environment_stack = NULL;
 116 static stack_entry_t      *label_stack       = NULL;
 117 static stack_entry_t      *local_label_stack = NULL;
 118 /** The global file scope. */
 119 static scope_t            *file_scope        = NULL;
 120 /** The current scope. */
 121 static scope_t            *scope             = NULL;
 122 static declaration_t      *last_declaration  = NULL;
 123 /** Point to the current function declaration if inside a function. */
 124 static declaration_t      *current_function  = NULL;
 125 static declaration_t      *current_init_decl = NULL;
 126 static switch_statement_t *current_switch    = NULL;
 127 static statement_t        *current_loop      = NULL;
 128 static statement_t        *current_parent    = NULL;
 129 static ms_try_statement_t *current_try       = NULL;
 130 static goto_statement_t   *goto_first        = NULL;
 131 static goto_statement_t   *goto_last         = NULL;
 132 static label_statement_t  *label_first       = NULL;
 133 static label_statement_t  *label_last        = NULL;
 134 /** current translation unit. */
 135 static translation_unit_t *unit              = NULL;
 136 /** true if we are in a type property context (evaluation only for type. */
 137 static bool                in_type_prop      = false;
 138 /** true in we are in a __extension__ context. */
 139 static bool                in_gcc_extension  = false;
 140 static struct obstack      temp_obst;
 141
 142
 143 #define PUSH_PARENT(stmt)                          \
 144         statement_t *const prev_parent = current_parent; \
 145         ((void)(current_parent = (stmt)))
 146 #define POP_PARENT ((void)(current_parent = prev_parent))
 147
 148 /** special symbol used for anonymous entities. */
 149 static const symbol_t *sym_anonymous = NULL;
 150
 151 /* symbols for Microsoft extended-decl-modifier */
 152 static const symbol_t *sym_align      = NULL;
 153 static const symbol_t *sym_allocate   = NULL;
 154 static const symbol_t *sym_dllimport  = NULL;
 155 static const symbol_t *sym_dllexport  = NULL;
 156 static const symbol_t *sym_naked      = NULL;
 157 static const symbol_t *sym_noinline   = NULL;
 158 static const symbol_t *sym_noreturn   = NULL;
 159 static const symbol_t *sym_nothrow    = NULL;
 160 static const symbol_t *sym_novtable   = NULL;
 161 static const symbol_t *sym_property   = NULL;
 162 static const symbol_t *sym_get        = NULL;
 163 static const symbol_t *sym_put        = NULL;
 164 static const symbol_t *sym_selectany  = NULL;
 165 static const symbol_t *sym_thread     = NULL;
 166 static const symbol_t *sym_uuid       = NULL;
 167 static const symbol_t *sym_deprecated = NULL;
 168 static const symbol_t *sym_restrict   = NULL;
 169 static const symbol_t *sym_noalias    = NULL;
 170
 171 /** The token anchor set */
 172 static unsigned char token_anchor_set[T_LAST_TOKEN];
 173
 174 /** The current source position. */
 175 #define HERE (&token.source_position)
 176
 177 /** true if we are in GCC mode. */
 178 #define GNU_MODE ((c_mode & _GNUC) || in_gcc_extension)
 179
 180 static type_t *type_valist;
 181
 182 static statement_t *parse_compound_statement(bool inside_expression_statement);
 183 static statement_t *parse_statement(void);
 184
 185 static expression_t *parse_sub_expression(precedence_t);
 186 static expression_t *parse_expression(void);
 187 static type_t       *parse_typename(void);
 188
 189 static void parse_compound_type_entries(declaration_t *compound_declaration);
 190 static declaration_t *parse_declarator(
 191                 const declaration_specifiers_t *specifiers, bool may_be_abstract);
 192 static declaration_t *record_declaration(declaration_t *declaration, bool is_definition);
 193
 194 static void semantic_comparison(binary_expression_t *expression);
 195
 196 #define STORAGE_CLASSES     \
 197         case T_typedef:         \
 198         case T_extern:          \
 199         case T_static:          \
 200         case T_auto:            \
 201         case T_register:        \
 202         case T___thread:
 203
 204 #define TYPE_QUALIFIERS     \
 205         case T_const:           \
 206         case T_restrict:        \
 207         case T_volatile:        \
 208         case T_inline:          \
 209         case T__forceinline:    \
 210         case T___attribute__:
 211
 212 #ifdef PROVIDE_COMPLEX
 213 #define COMPLEX_SPECIFIERS  \
 214         case T__Complex:
 215 #define IMAGINARY_SPECIFIERS \
 216         case T__Imaginary:
 217 #else
 218 #define COMPLEX_SPECIFIERS
 219 #define IMAGINARY_SPECIFIERS
 220 #endif
 221
 222 #define TYPE_SPECIFIERS       \
 223         case T_void:              \
 224         case T_char:              \
 225         case T_short:             \
 226         case T_int:               \
 227         case T_long:              \
 228         case T_float:             \
 229         case T_double:            \
 230         case T_signed:            \
 231         case T_unsigned:          \
 232         case T__Bool:             \
 233         case T_struct:            \
 234         case T_union:             \
 235         case T_enum:              \
 236         case T___typeof__:        \
 237         case T___builtin_va_list: \
 238         case T__declspec:         \
 239         COMPLEX_SPECIFIERS        \
 240         IMAGINARY_SPECIFIERS
 241
 242 #define DECLARATION_START   \
 243         STORAGE_CLASSES         \
 244         TYPE_QUALIFIERS         \
 245         TYPE_SPECIFIERS
 246
 247 #define TYPENAME_START      \
 248         TYPE_QUALIFIERS         \
 249         TYPE_SPECIFIERS
 250
 251 #define EXPRESSION_START           \
 252         case '!':                        \
 253         case '&':                        \
 254         case '(':                        \
 255         case '*':                        \
 256         case '+':                        \
 257         case '-':                        \
 258         case '~':                        \
 259         case T_ANDAND:                   \
 260         case T_CHARACTER_CONSTANT:       \
 261         case T_FLOATINGPOINT:            \
 262         case T_INTEGER:                  \
 263         case T_MINUSMINUS:               \
 264         case T_PLUSPLUS:                 \
 265         case T_STRING_LITERAL:           \
 266         case T_WIDE_CHARACTER_CONSTANT:  \
 267         case T_WIDE_STRING_LITERAL:      \
 268         case T___FUNCDNAME__:            \
 269         case T___FUNCSIG__:              \
 270         case T___FUNCTION__:             \
 271         case T___PRETTY_FUNCTION__:      \
 272         case T___alignof__:              \
 273         case T___builtin_alloca:         \
 274         case T___builtin_classify_type:  \
 275         case T___builtin_constant_p:     \
 276         case T___builtin_expect:         \
 277         case T___builtin_huge_val:       \
 278         case T___builtin_inf:            \
 279         case T___builtin_inff:           \
 280         case T___builtin_infl:           \
 281         case T___builtin_isgreater:      \
 282         case T___builtin_isgreaterequal: \
 283         case T___builtin_isless:         \
 284         case T___builtin_islessequal:    \
 285         case T___builtin_islessgreater:  \
 286         case T___builtin_isunordered:    \
 287         case T___builtin_nan:            \
 288         case T___builtin_nanf:           \
 289         case T___builtin_nanl:           \
 290         case T___builtin_offsetof:       \
 291         case T___builtin_prefetch:       \
 292         case T___builtin_va_arg:         \
 293         case T___builtin_va_end:         \
 294         case T___builtin_va_start:       \
 295         case T___func__:                 \
 296         case T___noop:                   \
 297         case T__assume:                  \
 298         case T_sizeof:                   \
 299         case T_throw:
 300
 301 /**
 302  * Allocate an AST node with given size and
 303  * initialize all fields with zero.
 304  */
 305 static void *allocate_ast_zero(size_t size)
 306 {
 307         void *res = allocate_ast(size);
 308         memset(res, 0, size);
 309         return res;
 310 }
 311
 312 static declaration_t *allocate_declaration_zero(void)
 313 {
 314         declaration_t *declaration = allocate_ast_zero(sizeof(declaration_t));
 315         declaration->type      = type_error_type;
 316         declaration->alignment = 0;
 317         return declaration;
 318 }
 319
 320 /**
 321  * Returns the size of a statement node.
 322  *
 323  * @param kind  the statement kind
 324  */
 325 static size_t get_statement_struct_size(statement_kind_t kind)
 326 {
 327         static const size_t sizes[] = {
 328                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 329                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 330                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 331                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 332                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 333                 [STATEMENT_IF]          = sizeof(if_statement_t),
 334                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 335                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 336                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 337                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 338                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 339                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 340                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 341                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 342                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 343                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 344                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 345                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 346                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 347         };
 348         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 349         assert(sizes[kind] != 0);
 350         return sizes[kind];
 351 }
 352
 353 /**
 354  * Returns the size of an expression node.
 355  *
 356  * @param kind  the expression kind
 357  */
 358 static size_t get_expression_struct_size(expression_kind_t kind)
 359 {
 360         static const size_t sizes[] = {
 361                 [EXPR_INVALID]                 = sizeof(expression_base_t),
 362                 [EXPR_REFERENCE]               = sizeof(reference_expression_t),
 363                 [EXPR_CONST]                   = sizeof(const_expression_t),
 364                 [EXPR_CHARACTER_CONSTANT]      = sizeof(const_expression_t),
 365                 [EXPR_WIDE_CHARACTER_CONSTANT] = sizeof(const_expression_t),
 366                 [EXPR_STRING_LITERAL]          = sizeof(string_literal_expression_t),
 367                 [EXPR_WIDE_STRING_LITERAL]     = sizeof(wide_string_literal_expression_t),
 368                 [EXPR_COMPOUND_LITERAL]        = sizeof(compound_literal_expression_t),
 369                 [EXPR_CALL]                    = sizeof(call_expression_t),
 370                 [EXPR_UNARY_FIRST]             = sizeof(unary_expression_t),
 371                 [EXPR_BINARY_FIRST]            = sizeof(binary_expression_t),
 372                 [EXPR_CONDITIONAL]             = sizeof(conditional_expression_t),
 373                 [EXPR_SELECT]                  = sizeof(select_expression_t),
 374                 [EXPR_ARRAY_ACCESS]            = sizeof(array_access_expression_t),
 375                 [EXPR_SIZEOF]                  = sizeof(typeprop_expression_t),
 376                 [EXPR_ALIGNOF]                 = sizeof(typeprop_expression_t),
 377                 [EXPR_CLASSIFY_TYPE]           = sizeof(classify_type_expression_t),
 378                 [EXPR_FUNCNAME]                = sizeof(funcname_expression_t),
 379                 [EXPR_BUILTIN_SYMBOL]          = sizeof(builtin_symbol_expression_t),
 380                 [EXPR_BUILTIN_CONSTANT_P]      = sizeof(builtin_constant_expression_t),
 381                 [EXPR_BUILTIN_PREFETCH]        = sizeof(builtin_prefetch_expression_t),
 382                 [EXPR_OFFSETOF]                = sizeof(offsetof_expression_t),
 383                 [EXPR_VA_START]                = sizeof(va_start_expression_t),
 384                 [EXPR_VA_ARG]                  = sizeof(va_arg_expression_t),
 385                 [EXPR_STATEMENT]               = sizeof(statement_expression_t),
 386                 [EXPR_LABEL_ADDRESS]           = sizeof(label_address_expression_t),
 387         };
 388         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 389                 return sizes[EXPR_UNARY_FIRST];
 390         }
 391         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 392                 return sizes[EXPR_BINARY_FIRST];
 393         }
 394         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 395         assert(sizes[kind] != 0);
 396         return sizes[kind];
 397 }
 398
 399 /**
 400  * Allocate a statement node of given kind and initialize all
 401  * fields with zero.
 402  */
 403 static statement_t *allocate_statement_zero(statement_kind_t kind)
 404 {
 405         size_t       size = get_statement_struct_size(kind);
 406         statement_t *res  = allocate_ast_zero(size);
 407
 408         res->base.kind            = kind;
 409         res->base.parent          = current_parent;
 410         res->base.source_position = token.source_position;
 411         return res;
 412 }
 413
 414 /**
 415  * Allocate an expression node of given kind and initialize all
 416  * fields with zero.
 417  */
 418 static expression_t *allocate_expression_zero(expression_kind_t kind)
 419 {
 420         size_t        size = get_expression_struct_size(kind);
 421         expression_t *res  = allocate_ast_zero(size);
 422
 423         res->base.kind = kind;
 424         res->base.type = type_error_type;
 425         return res;
 426 }
 427
 428 /**
 429  * Creates a new invalid expression.
 430  */
 431 static expression_t *create_invalid_expression(void)
 432 {
 433         expression_t *expression         = allocate_expression_zero(EXPR_INVALID);
 434         expression->base.source_position = token.source_position;
 435         return expression;
 436 }
 437
 438 /**
 439  * Creates a new invalid statement.
 440  */
 441 static statement_t *create_invalid_statement(void)
 442 {
 443         return allocate_statement_zero(STATEMENT_INVALID);
 444 }
 445
 446 /**
 447  * Allocate a new empty statement.
 448  */
 449 static statement_t *create_empty_statement(void)
 450 {
 451         return allocate_statement_zero(STATEMENT_EMPTY);
 452 }
 453
 454 /**
 455  * Returns the size of a type node.
 456  *
 457  * @param kind  the type kind
 458  */
 459 static size_t get_type_struct_size(type_kind_t kind)
 460 {
 461         static const size_t sizes[] = {
 462                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
 463                 [TYPE_COMPLEX]         = sizeof(complex_type_t),
 464                 [TYPE_IMAGINARY]       = sizeof(imaginary_type_t),
 465                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
 466                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
 467                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
 468                 [TYPE_ENUM]            = sizeof(enum_type_t),
 469                 [TYPE_FUNCTION]        = sizeof(function_type_t),
 470                 [TYPE_POINTER]         = sizeof(pointer_type_t),
 471                 [TYPE_ARRAY]           = sizeof(array_type_t),
 472                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
 473                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
 474                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
 475         };
 476         assert(sizeof(sizes) / sizeof(sizes[0]) == (int) TYPE_TYPEOF + 1);
 477         assert(kind <= TYPE_TYPEOF);
 478         assert(sizes[kind] != 0);
 479         return sizes[kind];
 480 }
 481
 482 /**
 483  * Allocate a type node of given kind and initialize all
 484  * fields with zero.
 485  *
 486  * @param kind             type kind to allocate
 487  */
 488 static type_t *allocate_type_zero(type_kind_t kind)
 489 {
 490         size_t  size = get_type_struct_size(kind);
 491         type_t *res  = obstack_alloc(type_obst, size);
 492         memset(res, 0, size);
 493         res->base.kind = kind;
 494
 495         return res;
 496 }
 497
 498 /**
 499  * Returns the size of an initializer node.
 500  *
 501  * @param kind  the initializer kind
 502  */
 503 static size_t get_initializer_size(initializer_kind_t kind)
 504 {
 505         static const size_t sizes[] = {
 506                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 507                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 508                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 509                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 510                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 511         };
 512         assert(kind < sizeof(sizes) / sizeof(*sizes));
 513         assert(sizes[kind] != 0);
 514         return sizes[kind];
 515 }
 516
 517 /**
 518  * Allocate an initializer node of given kind and initialize all
 519  * fields with zero.
 520  */
 521 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 522 {
 523         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 524         result->kind          = kind;
 525
 526         return result;
 527 }
 528
 529 /**
 530  * Free a type from the type obstack.
 531  */
 532 static void free_type(void *type)
 533 {
 534         obstack_free(type_obst, type);
 535 }
 536
 537 /**
 538  * Returns the index of the top element of the environment stack.
 539  */
 540 static size_t environment_top(void)
 541 {
 542         return ARR_LEN(environment_stack);
 543 }
 544
 545 /**
 546  * Returns the index of the top element of the global label stack.
 547  */
 548 static size_t label_top(void)
 549 {
 550         return ARR_LEN(label_stack);
 551 }
 552
 553 /**
 554  * Returns the index of the top element of the local label stack.
 555  */
 556 static size_t local_label_top(void)
 557 {
 558         return ARR_LEN(local_label_stack);
 559 }
 560
 561 /**
 562  * Return the next token.
 563  */
 564 static inline void next_token(void)
 565 {
 566         token                              = lookahead_buffer[lookahead_bufpos];
 567         lookahead_buffer[lookahead_bufpos] = lexer_token;
 568         lexer_next_token();
 569
 570         lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
 571
 572 #ifdef PRINT_TOKENS
 573         print_token(stderr, &token);
 574         fprintf(stderr, "\n");
 575 #endif
 576 }
 577
 578 /**
 579  * Return the next token with a given lookahead.
 580  */
 581 static inline const token_t *look_ahead(int num)
 582 {
 583         assert(num > 0 && num <= MAX_LOOKAHEAD);
 584         int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
 585         return &lookahead_buffer[pos];
 586 }
 587
 588 /**
 589  * Adds a token to the token anchor set (a multi-set).
 590  */
 591 static void add_anchor_token(int token_type)
 592 {
 593         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 594         ++token_anchor_set[token_type];
 595 }
 596
 597 static int save_and_reset_anchor_state(int token_type)
 598 {
 599         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 600         int count = token_anchor_set[token_type];
 601         token_anchor_set[token_type] = 0;
 602         return count;
 603 }
 604
 605 static void restore_anchor_state(int token_type, int count)
 606 {
 607         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 608         token_anchor_set[token_type] = count;
 609 }
 610
 611 /**
 612  * Remove a token from the token anchor set (a multi-set).
 613  */
 614 static void rem_anchor_token(int token_type)
 615 {
 616         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 617         assert(token_anchor_set[token_type] != 0);
 618         --token_anchor_set[token_type];
 619 }
 620
 621 static bool at_anchor(void)
 622 {
 623         if (token.type < 0)
 624                 return false;
 625         return token_anchor_set[token.type];
 626 }
 627
 628 /**
 629  * Eat tokens until a matching token is found.
 630  */
 631 static void eat_until_matching_token(int type)
 632 {
 633         int end_token;
 634         switch (type) {
 635                 case '(': end_token = ')';  break;
 636                 case '{': end_token = '}';  break;
 637                 case '[': end_token = ']';  break;
 638                 default:  end_token = type; break;
 639         }
 640
 641         unsigned parenthesis_count = 0;
 642         unsigned brace_count       = 0;
 643         unsigned bracket_count     = 0;
 644         while (token.type        != end_token ||
 645                parenthesis_count != 0         ||
 646                brace_count       != 0         ||
 647                bracket_count     != 0) {
 648                 switch (token.type) {
 649                 case T_EOF: return;
 650                 case '(': ++parenthesis_count; break;
 651                 case '{': ++brace_count;       break;
 652                 case '[': ++bracket_count;     break;
 653
 654                 case ')':
 655                         if (parenthesis_count > 0)
 656                                 --parenthesis_count;
 657                         goto check_stop;
 658
 659                 case '}':
 660                         if (brace_count > 0)
 661                                 --brace_count;
 662                         goto check_stop;
 663
 664                 case ']':
 665                         if (bracket_count > 0)
 666                                 --bracket_count;
 667 check_stop:
 668                         if (token.type        == end_token &&
 669                             parenthesis_count == 0         &&
 670                             brace_count       == 0         &&
 671                             bracket_count     == 0)
 672                                 return;
 673                         break;
 674
 675                 default:
 676                         break;
 677                 }
 678                 next_token();
 679         }
 680 }
 681
 682 /**
 683  * Eat input tokens until an anchor is found.
 684  */
 685 static void eat_until_anchor(void)
 686 {
 687         while (token_anchor_set[token.type] == 0) {
 688                 if (token.type == '(' || token.type == '{' || token.type == '[')
 689                         eat_until_matching_token(token.type);
 690                 next_token();
 691         }
 692 }
 693
 694 static void eat_block(void)
 695 {
 696         eat_until_matching_token('{');
 697         if (token.type == '}')
 698                 next_token();
 699 }
 700
 701 #define eat(token_type)  do { assert(token.type == token_type); next_token(); } while (0)
 702
 703 /**
 704  * Report a parse error because an expected token was not found.
 705  */
 706 static
 707 #if defined __GNUC__ && __GNUC__ >= 4
 708 __attribute__((sentinel))
 709 #endif
 710 void parse_error_expected(const char *message, ...)
 711 {
 712         if (message != NULL) {
 713                 errorf(HERE, "%s", message);
 714         }
 715         va_list ap;
 716         va_start(ap, message);
 717         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 718         va_end(ap);
 719 }
 720
 721 /**
 722  * Report a type error.
 723  */
 724 static void type_error(const char *msg, const source_position_t *source_position,
 725                        type_t *type)
 726 {
 727         errorf(source_position, "%s, but found type '%T'", msg, type);
 728 }
 729
 730 /**
 731  * Report an incompatible type.
 732  */
 733 static void type_error_incompatible(const char *msg,
 734                 const source_position_t *source_position, type_t *type1, type_t *type2)
 735 {
 736         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 737                msg, type1, type2);
 738 }
 739
 740 /**
 741  * Expect the the current token is the expected token.
 742  * If not, generate an error, eat the current statement,
 743  * and goto the end_error label.
 744  */
 745 #define expect(expected)                                  \
 746         do {                                                  \
 747                 if (UNLIKELY(token.type != (expected))) {         \
 748                         parse_error_expected(NULL, (expected), NULL); \
 749                         add_anchor_token(expected);                   \
 750                         eat_until_anchor();                           \
 751                         if (token.type == expected)                   \
 752                                 next_token();                             \
 753                         rem_anchor_token(expected);                   \
 754                         goto end_error;                               \
 755                 }                                                 \
 756                 next_token();                                     \
 757         } while (0)
 758
 759 static void scope_push(scope_t *new_scope)
 760 {
 761         if (scope != NULL) {
 762                 scope->last_declaration = last_declaration;
 763                 new_scope->depth        = scope->depth + 1;
 764         }
 765         new_scope->parent = scope;
 766         scope             = new_scope;
 767
 768         last_declaration = new_scope->last_declaration;
 769 }
 770
 771 static void scope_pop(void)
 772 {
 773         scope->last_declaration = last_declaration;
 774         scope = scope->parent;
 775         last_declaration = scope->last_declaration;
 776 }
 777
 778 /**
 779  * Search a symbol in a given namespace and returns its declaration or
 780  * NULL if this symbol was not found.
 781  */
 782 static declaration_t *get_declaration(const symbol_t *const symbol,
 783                                       const namespace_t namespc)
 784 {
 785         declaration_t *declaration = symbol->declaration;
 786         for( ; declaration != NULL; declaration = declaration->symbol_next) {
 787                 if (declaration->namespc == namespc)
 788                         return declaration;
 789         }
 790
 791         return NULL;
 792 }
 793
 794 /**
 795  * pushs an environment_entry on the environment stack and links the
 796  * corresponding symbol to the new entry
 797  */
 798 static void stack_push(stack_entry_t **stack_ptr, declaration_t *declaration)
 799 {
 800         symbol_t    *symbol  = declaration->symbol;
 801         namespace_t  namespc = (namespace_t) declaration->namespc;
 802
 803         /* replace/add declaration into declaration list of the symbol */
 804         declaration_t **anchor;
 805         declaration_t  *iter;
 806         for (anchor = &symbol->declaration;; anchor = &iter->symbol_next) {
 807                 iter = *anchor;
 808                 if (iter == NULL)
 809                         break;
 810
 811                 /* replace an entry? */
 812                 if (iter->namespc == namespc) {
 813                         declaration->symbol_next = iter->symbol_next;
 814                         break;
 815                 }
 816         }
 817         *anchor = declaration;
 818
 819         /* remember old declaration */
 820         stack_entry_t entry;
 821         entry.symbol          = symbol;
 822         entry.old_declaration = iter;
 823         entry.namespc         = (unsigned short) namespc;
 824         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 825 }
 826
 827 /**
 828  * Push a declaration on the environment stack.
 829  *
 830  * @param declaration  the declaration
 831  */
 832 static void environment_push(declaration_t *declaration)
 833 {
 834         assert(declaration->source_position.input_name != NULL);
 835         assert(declaration->parent_scope != NULL);
 836         stack_push(&environment_stack, declaration);
 837 }
 838
 839 /**
 840  * Push a declaration on the global label stack.
 841  *
 842  * @param declaration  the declaration
 843  */
 844 static void label_push(declaration_t *declaration)
 845 {
 846         declaration->parent_scope = &current_function->scope;
 847         stack_push(&label_stack, declaration);
 848 }
 849
 850 /**
 851  * Push a declaration of the local label stack.
 852  *
 853  * @param declaration  the declaration
 854  */
 855 static void local_label_push(declaration_t *declaration)
 856 {
 857         assert(declaration->parent_scope != NULL);
 858         stack_push(&local_label_stack, declaration);
 859 }
 860
 861 /**
 862  * pops symbols from the environment stack until @p new_top is the top element
 863  */
 864 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 865 {
 866         stack_entry_t *stack = *stack_ptr;
 867         size_t         top   = ARR_LEN(stack);
 868         size_t         i;
 869
 870         assert(new_top <= top);
 871         if (new_top == top)
 872                 return;
 873
 874         for(i = top; i > new_top; --i) {
 875                 stack_entry_t *entry = &stack[i - 1];
 876
 877                 declaration_t *old_declaration = entry->old_declaration;
 878                 symbol_t      *symbol          = entry->symbol;
 879                 namespace_t    namespc         = (namespace_t)entry->namespc;
 880
 881                 /* replace/remove declaration */
 882                 declaration_t **anchor;
 883                 declaration_t  *iter;
 884                 for (anchor = &symbol->declaration;; anchor = &iter->symbol_next) {
 885                         iter = *anchor;
 886                         assert(iter != NULL);
 887                         /* replace an entry? */
 888                         if (iter->namespc == namespc)
 889                                 break;
 890                 }
 891
 892                 /* Not all declarations adhere scopes (e.g. jump labels), so this
 893                  * correction is necessary */
 894                 if (old_declaration != NULL) {
 895                         old_declaration->symbol_next = iter->symbol_next;
 896                         *anchor = old_declaration;
 897                 } else {
 898                         *anchor = iter->symbol_next;
 899                 }
 900         }
 901
 902         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
 903 }
 904
 905 /**
 906  * Pop all entries from the environment stack until the new_top
 907  * is reached.
 908  *
 909  * @param new_top  the new stack top
 910  */
 911 static void environment_pop_to(size_t new_top)
 912 {
 913         stack_pop_to(&environment_stack, new_top);
 914 }
 915
 916 /**
 917  * Pop all entries from the global label stack until the new_top
 918  * is reached.
 919  *
 920  * @param new_top  the new stack top
 921  */
 922 static void label_pop_to(size_t new_top)
 923 {
 924         stack_pop_to(&label_stack, new_top);
 925 }
 926
 927 /**
 928  * Pop all entries from the local label stack until the new_top
 929  * is reached.
 930  *
 931  * @param new_top  the new stack top
 932  */
 933 static void local_label_pop_to(size_t new_top)
 934 {
 935         stack_pop_to(&local_label_stack, new_top);
 936 }
 937
 938
 939 static int get_akind_rank(atomic_type_kind_t akind)
 940 {
 941         return (int) akind;
 942 }
 943
 944 static int get_rank(const type_t *type)
 945 {
 946         assert(!is_typeref(type));
 947         /* The C-standard allows promoting enums to int or unsigned int (see § 7.2.2
 948          * and esp. footnote 108). However we can't fold constants (yet), so we
 949          * can't decide whether unsigned int is possible, while int always works.
 950          * (unsigned int would be preferable when possible... for stuff like
 951          *  struct { enum { ... } bla : 4; } ) */
 952         if (type->kind == TYPE_ENUM)
 953                 return get_akind_rank(ATOMIC_TYPE_INT);
 954
 955         assert(type->kind == TYPE_ATOMIC);
 956         return get_akind_rank(type->atomic.akind);
 957 }
 958
 959 static type_t *promote_integer(type_t *type)
 960 {
 961         if (type->kind == TYPE_BITFIELD)
 962                 type = type->bitfield.base_type;
 963
 964         if (get_rank(type) < get_akind_rank(ATOMIC_TYPE_INT))
 965                 type = type_int;
 966
 967         return type;
 968 }
 969
 970 /**
 971  * Create a cast expression.
 972  *
 973  * @param expression  the expression to cast
 974  * @param dest_type   the destination type
 975  */
 976 static expression_t *create_cast_expression(expression_t *expression,
 977                                             type_t *dest_type)
 978 {
 979         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
 980
 981         cast->unary.value = expression;
 982         cast->base.type   = dest_type;
 983
 984         return cast;
 985 }
 986
 987 /**
 988  * Check if a given expression represents the 0 pointer constant.
 989  */
 990 static bool is_null_pointer_constant(const expression_t *expression)
 991 {
 992         /* skip void* cast */
 993         if (expression->kind == EXPR_UNARY_CAST
 994                         || expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
 995                 expression = expression->unary.value;
 996         }
 997
 998         /* TODO: not correct yet, should be any constant integer expression
 999          * which evaluates to 0 */
1000         if (expression->kind != EXPR_CONST)
1001                 return false;
1002
1003         type_t *const type = skip_typeref(expression->base.type);
1004         if (!is_type_integer(type))
1005                 return false;
1006
1007         return expression->conste.v.int_value == 0;
1008 }
1009
1010 /**
1011  * Create an implicit cast expression.
1012  *
1013  * @param expression  the expression to cast
1014  * @param dest_type   the destination type
1015  */
1016 static expression_t *create_implicit_cast(expression_t *expression,
1017                                           type_t *dest_type)
1018 {
1019         type_t *const source_type = expression->base.type;
1020
1021         if (source_type == dest_type)
1022                 return expression;
1023
1024         return create_cast_expression(expression, dest_type);
1025 }
1026
1027 typedef enum assign_error_t {
1028         ASSIGN_SUCCESS,
1029         ASSIGN_ERROR_INCOMPATIBLE,
1030         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
1031         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
1032         ASSIGN_WARNING_POINTER_FROM_INT,
1033         ASSIGN_WARNING_INT_FROM_POINTER
1034 } assign_error_t;
1035
1036 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
1037                                 const expression_t *const right,
1038                                 const char *context,
1039                                 const source_position_t *source_position)
1040 {
1041         type_t *const orig_type_right = right->base.type;
1042         type_t *const type_left       = skip_typeref(orig_type_left);
1043         type_t *const type_right      = skip_typeref(orig_type_right);
1044
1045         switch (error) {
1046         case ASSIGN_SUCCESS:
1047                 return;
1048         case ASSIGN_ERROR_INCOMPATIBLE:
1049                 errorf(source_position,
1050                        "destination type '%T' in %s is incompatible with type '%T'",
1051                        orig_type_left, context, orig_type_right);
1052                 return;
1053
1054         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
1055                 if (warning.other) {
1056                         type_t *points_to_left  = skip_typeref(type_left->pointer.points_to);
1057                         type_t *points_to_right = skip_typeref(type_right->pointer.points_to);
1058
1059                         /* the left type has all qualifiers from the right type */
1060                         unsigned missing_qualifiers
1061                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1062                         warningf(source_position,
1063                                         "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
1064                                         orig_type_left, context, orig_type_right, missing_qualifiers);
1065                 }
1066                 return;
1067         }
1068
1069         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
1070                 if (warning.other) {
1071                         warningf(source_position,
1072                                         "destination type '%T' in %s is incompatible with '%E' of type '%T'",
1073                                         orig_type_left, context, right, orig_type_right);
1074                 }
1075                 return;
1076
1077         case ASSIGN_WARNING_POINTER_FROM_INT:
1078                 if (warning.other) {
1079                         warningf(source_position,
1080                                         "%s makes pointer '%T' from integer '%T' without a cast",
1081                                         context, orig_type_left, orig_type_right);
1082                 }
1083                 return;
1084
1085         case ASSIGN_WARNING_INT_FROM_POINTER:
1086                 if (warning.other) {
1087                         warningf(source_position,
1088                                         "%s makes integer '%T' from pointer '%T' without a cast",
1089                                         context, orig_type_left, orig_type_right);
1090                 }
1091                 return;
1092
1093         default:
1094                 panic("invalid error value");
1095         }
1096 }
1097
1098 /** Implements the rules from § 6.5.16.1 */
1099 static assign_error_t semantic_assign(type_t *orig_type_left,
1100                                       const expression_t *const right)
1101 {
1102         type_t *const orig_type_right = right->base.type;
1103         type_t *const type_left       = skip_typeref(orig_type_left);
1104         type_t *const type_right      = skip_typeref(orig_type_right);
1105
1106         if (is_type_pointer(type_left)) {
1107                 if (is_null_pointer_constant(right)) {
1108                         return ASSIGN_SUCCESS;
1109                 } else if (is_type_pointer(type_right)) {
1110                         type_t *points_to_left
1111                                 = skip_typeref(type_left->pointer.points_to);
1112                         type_t *points_to_right
1113                                 = skip_typeref(type_right->pointer.points_to);
1114                         assign_error_t res = ASSIGN_SUCCESS;
1115
1116                         /* the left type has all qualifiers from the right type */
1117                         unsigned missing_qualifiers
1118                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1119                         if (missing_qualifiers != 0) {
1120                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1121                         }
1122
1123                         points_to_left  = get_unqualified_type(points_to_left);
1124                         points_to_right = get_unqualified_type(points_to_right);
1125
1126                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID) ||
1127                                         is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1128                                 return res;
1129                         }
1130
1131                         if (!types_compatible(points_to_left, points_to_right)) {
1132                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1133                         }
1134
1135                         return res;
1136                 } else if (is_type_integer(type_right)) {
1137                         return ASSIGN_WARNING_POINTER_FROM_INT;
1138                 }
1139         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1140             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1141                 && is_type_pointer(type_right))) {
1142                 return ASSIGN_SUCCESS;
1143         } else if ((is_type_compound(type_left)  && is_type_compound(type_right))
1144                         || (is_type_builtin(type_left) && is_type_builtin(type_right))) {
1145                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1146                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1147                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1148                         return ASSIGN_SUCCESS;
1149                 }
1150         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1151                 return ASSIGN_WARNING_INT_FROM_POINTER;
1152         }
1153
1154         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1155                 return ASSIGN_SUCCESS;
1156
1157         return ASSIGN_ERROR_INCOMPATIBLE;
1158 }
1159
1160 static expression_t *parse_constant_expression(void)
1161 {
1162         expression_t *result = parse_sub_expression(PREC_CONDITIONAL);
1163
1164         if (!is_constant_expression(result)) {
1165                 errorf(&result->base.source_position,
1166                        "expression '%E' is not constant\n", result);
1167         }
1168
1169         return result;
1170 }
1171
1172 static expression_t *parse_assignment_expression(void)
1173 {
1174         return parse_sub_expression(PREC_ASSIGNMENT);
1175 }
1176
1177 static type_t *make_global_typedef(const char *name, type_t *type)
1178 {
1179         symbol_t *const symbol       = symbol_table_insert(name);
1180
1181         declaration_t *const declaration = allocate_declaration_zero();
1182         declaration->namespc                = NAMESPACE_NORMAL;
1183         declaration->storage_class          = STORAGE_CLASS_TYPEDEF;
1184         declaration->declared_storage_class = STORAGE_CLASS_TYPEDEF;
1185         declaration->type                   = type;
1186         declaration->symbol                 = symbol;
1187         declaration->source_position        = builtin_source_position;
1188         declaration->implicit               = true;
1189
1190         record_declaration(declaration, false);
1191
1192         type_t *typedef_type               = allocate_type_zero(TYPE_TYPEDEF);
1193         typedef_type->typedeft.declaration = declaration;
1194
1195         return typedef_type;
1196 }
1197
1198 static string_t parse_string_literals(void)
1199 {
1200         assert(token.type == T_STRING_LITERAL);
1201         string_t result = token.v.string;
1202
1203         next_token();
1204
1205         while (token.type == T_STRING_LITERAL) {
1206                 result = concat_strings(&result, &token.v.string);
1207                 next_token();
1208         }
1209
1210         return result;
1211 }
1212
1213 static const char *const gnu_attribute_names[GNU_AK_LAST] = {
1214         [GNU_AK_CONST]                  = "const",
1215         [GNU_AK_VOLATILE]               = "volatile",
1216         [GNU_AK_CDECL]                  = "cdecl",
1217         [GNU_AK_STDCALL]                = "stdcall",
1218         [GNU_AK_FASTCALL]               = "fastcall",
1219         [GNU_AK_DEPRECATED]             = "deprecated",
1220         [GNU_AK_NOINLINE]               = "noinline",
1221         [GNU_AK_NORETURN]               = "noreturn",
1222         [GNU_AK_NAKED]                  = "naked",
1223         [GNU_AK_PURE]                   = "pure",
1224         [GNU_AK_ALWAYS_INLINE]          = "always_inline",
1225         [GNU_AK_MALLOC]                 = "malloc",
1226         [GNU_AK_WEAK]                   = "weak",
1227         [GNU_AK_CONSTRUCTOR]            = "constructor",
1228         [GNU_AK_DESTRUCTOR]             = "destructor",
1229         [GNU_AK_NOTHROW]                = "nothrow",
1230         [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
1231         [GNU_AK_COMMON]                 = "common",
1232         [GNU_AK_NOCOMMON]               = "nocommon",
1233         [GNU_AK_PACKED]                 = "packed",
1234         [GNU_AK_SHARED]                 = "shared",
1235         [GNU_AK_NOTSHARED]              = "notshared",
1236         [GNU_AK_USED]                   = "used",
1237         [GNU_AK_UNUSED]                 = "unused",
1238         [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
1239         [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
1240         [GNU_AK_LONGCALL]               = "longcall",
1241         [GNU_AK_SHORTCALL]              = "shortcall",
1242         [GNU_AK_LONG_CALL]              = "long_call",
1243         [GNU_AK_SHORT_CALL]             = "short_call",
1244         [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
1245         [GNU_AK_INTERRUPT]              = "interrupt",
1246         [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
1247         [GNU_AK_NMI_HANDLER]            = "nmi_handler",
1248         [GNU_AK_NESTING]                = "nesting",
1249         [GNU_AK_NEAR]                   = "near",
1250         [GNU_AK_FAR]                    = "far",
1251         [GNU_AK_SIGNAL]                 = "signal",
1252         [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
1253         [GNU_AK_TINY_DATA]              = "tiny_data",
1254         [GNU_AK_SAVEALL]                = "saveall",
1255         [GNU_AK_FLATTEN]                = "flatten",
1256         [GNU_AK_SSEREGPARM]             = "sseregparm",
1257         [GNU_AK_EXTERNALLY_VISIBLE]     = "externally_visible",
1258         [GNU_AK_RETURN_TWICE]           = "return_twice",
1259         [GNU_AK_MAY_ALIAS]              = "may_alias",
1260         [GNU_AK_MS_STRUCT]              = "ms_struct",
1261         [GNU_AK_GCC_STRUCT]             = "gcc_struct",
1262         [GNU_AK_DLLIMPORT]              = "dllimport",
1263         [GNU_AK_DLLEXPORT]              = "dllexport",
1264         [GNU_AK_ALIGNED]                = "aligned",
1265         [GNU_AK_ALIAS]                  = "alias",
1266         [GNU_AK_SECTION]                = "section",
1267         [GNU_AK_FORMAT]                 = "format",
1268         [GNU_AK_FORMAT_ARG]             = "format_arg",
1269         [GNU_AK_WEAKREF]                = "weakref",
1270         [GNU_AK_NONNULL]                = "nonnull",
1271         [GNU_AK_TLS_MODEL]              = "tls_model",
1272         [GNU_AK_VISIBILITY]             = "visibility",
1273         [GNU_AK_REGPARM]                = "regparm",
1274         [GNU_AK_MODE]                   = "mode",
1275         [GNU_AK_MODEL]                  = "model",
1276         [GNU_AK_TRAP_EXIT]              = "trap_exit",
1277         [GNU_AK_SP_SWITCH]              = "sp_switch",
1278         [GNU_AK_SENTINEL]               = "sentinel"
1279 };
1280
1281 /**
1282  * compare two string, ignoring double underscores on the second.
1283  */
1284 static int strcmp_underscore(const char *s1, const char *s2)
1285 {
1286         if (s2[0] == '_' && s2[1] == '_') {
1287                 size_t len2 = strlen(s2);
1288                 size_t len1 = strlen(s1);
1289                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1290                         return strncmp(s1, s2+2, len2-4);
1291                 }
1292         }
1293
1294         return strcmp(s1, s2);
1295 }
1296
1297 /**
1298  * Allocate a new gnu temporal attribute.
1299  */
1300 static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
1301 {
1302         gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
1303         attribute->kind            = kind;
1304         attribute->next            = NULL;
1305         attribute->invalid         = false;
1306         attribute->have_arguments  = false;
1307
1308         return attribute;
1309 }
1310
1311 /**
1312  * parse one constant expression argument.
1313  */
1314 static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
1315 {
1316         expression_t *expression;
1317         add_anchor_token(')');
1318         expression = parse_constant_expression();
1319         rem_anchor_token(')');
1320         expect(')');
1321         attribute->u.argument = fold_constant(expression);
1322         return;
1323 end_error:
1324         attribute->invalid = true;
1325 }
1326
1327 /**
1328  * parse a list of constant expressions arguments.
1329  */
1330 static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
1331 {
1332         argument_list_t **list = &attribute->u.arguments;
1333         argument_list_t  *entry;
1334         expression_t     *expression;
1335         add_anchor_token(')');
1336         add_anchor_token(',');
1337         while (true) {
1338                 expression = parse_constant_expression();
1339                 entry = obstack_alloc(&temp_obst, sizeof(entry));
1340                 entry->argument = fold_constant(expression);
1341                 entry->next     = NULL;
1342                 *list = entry;
1343                 list = &entry->next;
1344                 if (token.type != ',')
1345                         break;
1346                 next_token();
1347         }
1348         rem_anchor_token(',');
1349         rem_anchor_token(')');
1350         expect(')');
1351         return;
1352 end_error:
1353         attribute->invalid = true;
1354 }
1355
1356 /**
1357  * parse one string literal argument.
1358  */
1359 static void parse_gnu_attribute_string_arg(gnu_attribute_t *attribute,
1360                                            string_t *string)
1361 {
1362         add_anchor_token('(');
1363         if (token.type != T_STRING_LITERAL) {
1364                 parse_error_expected("while parsing attribute directive",
1365                                      T_STRING_LITERAL, NULL);
1366                 goto end_error;
1367         }
1368         *string = parse_string_literals();
1369         rem_anchor_token('(');
1370         expect(')');
1371         return;
1372 end_error:
1373         attribute->invalid = true;
1374 }
1375
1376 /**
1377  * parse one tls model.
1378  */
1379 static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
1380 {
1381         static const char *const tls_models[] = {
1382                 "global-dynamic",
1383                 "local-dynamic",
1384                 "initial-exec",
1385                 "local-exec"
1386         };
1387         string_t string = { NULL, 0 };
1388         parse_gnu_attribute_string_arg(attribute, &string);
1389         if (string.begin != NULL) {
1390                 for(size_t i = 0; i < 4; ++i) {
1391                         if (strcmp(tls_models[i], string.begin) == 0) {
1392                                 attribute->u.value = i;
1393                                 return;
1394                         }
1395                 }
1396                 errorf(HERE, "'%s' is an unrecognized tls model", string.begin);
1397         }
1398         attribute->invalid = true;
1399 }
1400
1401 /**
1402  * parse one tls model.
1403  */
1404 static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
1405 {
1406         static const char *const visibilities[] = {
1407                 "default",
1408                 "protected",
1409                 "hidden",
1410                 "internal"
1411         };
1412         string_t string = { NULL, 0 };
1413         parse_gnu_attribute_string_arg(attribute, &string);
1414         if (string.begin != NULL) {
1415                 for(size_t i = 0; i < 4; ++i) {
1416                         if (strcmp(visibilities[i], string.begin) == 0) {
1417                                 attribute->u.value = i;
1418                                 return;
1419                         }
1420                 }
1421                 errorf(HERE, "'%s' is an unrecognized visibility", string.begin);
1422         }
1423         attribute->invalid = true;
1424 }
1425
1426 /**
1427  * parse one (code) model.
1428  */
1429 static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
1430 {
1431         static const char *const visibilities[] = {
1432                 "small",
1433                 "medium",
1434                 "large"
1435         };
1436         string_t string = { NULL, 0 };
1437         parse_gnu_attribute_string_arg(attribute, &string);
1438         if (string.begin != NULL) {
1439                 for(int i = 0; i < 3; ++i) {
1440                         if (strcmp(visibilities[i], string.begin) == 0) {
1441                                 attribute->u.value = i;
1442                                 return;
1443                         }
1444                 }
1445                 errorf(HERE, "'%s' is an unrecognized model", string.begin);
1446         }
1447         attribute->invalid = true;
1448 }
1449
1450 static void parse_gnu_attribute_mode_arg(gnu_attribute_t *attribute)
1451 {
1452         /* TODO: find out what is allowed here... */
1453
1454         /* at least: byte, word, pointer, list of machine modes
1455          * __XXX___ is interpreted as XXX */
1456         add_anchor_token(')');
1457
1458         if (token.type != T_IDENTIFIER) {
1459                 expect(T_IDENTIFIER);
1460         }
1461
1462         /* This isn't really correct, the backend should provide a list of machine
1463          * specific modes (according to gcc philosophy that is...) */
1464         const char *symbol_str = token.v.symbol->string;
1465         if (strcmp_underscore("QI",   symbol_str) == 0 ||
1466             strcmp_underscore("byte", symbol_str) == 0) {
1467                 attribute->u.akind = ATOMIC_TYPE_CHAR;
1468         } else if (strcmp_underscore("HI", symbol_str) == 0) {
1469                 attribute->u.akind = ATOMIC_TYPE_SHORT;
1470         } else if (strcmp_underscore("SI",      symbol_str) == 0
1471                 || strcmp_underscore("word",    symbol_str) == 0
1472                 || strcmp_underscore("pointer", symbol_str) == 0) {
1473                 attribute->u.akind = ATOMIC_TYPE_INT;
1474         } else if (strcmp_underscore("DI", symbol_str) == 0) {
1475                 attribute->u.akind = ATOMIC_TYPE_LONGLONG;
1476         } else {
1477                 if (warning.other)
1478                         warningf(HERE, "ignoring unknown mode '%s'", symbol_str);
1479                 attribute->invalid = true;
1480         }
1481         next_token();
1482
1483         rem_anchor_token(')');
1484         expect(')');
1485         return;
1486 end_error:
1487         attribute->invalid = true;
1488 }
1489
1490 /**
1491  * parse one interrupt argument.
1492  */
1493 static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
1494 {
1495         static const char *const interrupts[] = {
1496                 "IRQ",
1497                 "FIQ",
1498                 "SWI",
1499                 "ABORT",
1500                 "UNDEF"
1501         };
1502         string_t string = { NULL, 0 };
1503         parse_gnu_attribute_string_arg(attribute, &string);
1504         if (string.begin != NULL) {
1505                 for(size_t i = 0; i < 5; ++i) {
1506                         if (strcmp(interrupts[i], string.begin) == 0) {
1507                                 attribute->u.value = i;
1508                                 return;
1509                         }
1510                 }
1511                 errorf(HERE, "'%s' is not an interrupt", string.begin);
1512         }
1513         attribute->invalid = true;
1514 }
1515
1516 /**
1517  * parse ( identifier, const expression, const expression )
1518  */
1519 static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
1520 {
1521         static const char *const format_names[] = {
1522                 "printf",
1523                 "scanf",
1524                 "strftime",
1525                 "strfmon"
1526         };
1527         int i;
1528
1529         if (token.type != T_IDENTIFIER) {
1530                 parse_error_expected("while parsing format attribute directive", T_IDENTIFIER, NULL);
1531                 goto end_error;
1532         }
1533         const char *name = token.v.symbol->string;
1534         for(i = 0; i < 4; ++i) {
1535                 if (strcmp_underscore(format_names[i], name) == 0)
1536                         break;
1537         }
1538         if (i >= 4) {
1539                 if (warning.attribute)
1540                         warningf(HERE, "'%s' is an unrecognized format function type", name);
1541         }
1542         next_token();
1543
1544         expect(',');
1545         add_anchor_token(')');
1546         add_anchor_token(',');
1547         parse_constant_expression();
1548         rem_anchor_token(',');
1549         rem_anchor_token(')');
1550
1551         expect(',');
1552         add_anchor_token(')');
1553         parse_constant_expression();
1554         rem_anchor_token(')');
1555         expect(')');
1556         return;
1557 end_error:
1558         attribute->u.value = true;
1559 }
1560
1561 static void check_no_argument(gnu_attribute_t *attribute, const char *name)
1562 {
1563         if (!attribute->have_arguments)
1564                 return;
1565
1566         /* should have no arguments */
1567         errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1568         eat_until_matching_token('(');
1569         /* we have already consumed '(', so we stop before ')', eat it */
1570         eat(')');
1571         attribute->invalid = true;
1572 }
1573
1574 /**
1575  * Parse one GNU attribute.
1576  *
1577  * Note that attribute names can be specified WITH or WITHOUT
1578  * double underscores, ie const or __const__.
1579  *
1580  * The following attributes are parsed without arguments
1581  *  const
1582  *  volatile
1583  *  cdecl
1584  *  stdcall
1585  *  fastcall
1586  *  deprecated
1587  *  noinline
1588  *  noreturn
1589  *  naked
1590  *  pure
1591  *  always_inline
1592  *  malloc
1593  *  weak
1594  *  constructor
1595  *  destructor
1596  *  nothrow
1597  *  transparent_union
1598  *  common
1599  *  nocommon
1600  *  packed
1601  *  shared
1602  *  notshared
1603  *  used
1604  *  unused
1605  *  no_instrument_function
1606  *  warn_unused_result
1607  *  longcall
1608  *  shortcall
1609  *  long_call
1610  *  short_call
1611  *  function_vector
1612  *  interrupt_handler
1613  *  nmi_handler
1614  *  nesting
1615  *  near
1616  *  far
1617  *  signal
1618  *  eightbit_data
1619  *  tiny_data
1620  *  saveall
1621  *  flatten
1622  *  sseregparm
1623  *  externally_visible
1624  *  return_twice
1625  *  may_alias
1626  *  ms_struct
1627  *  gcc_struct
1628  *  dllimport
1629  *  dllexport
1630  *
1631  * The following attributes are parsed with arguments
1632  *  aligned( const expression )
1633  *  alias( string literal )
1634  *  section( string literal )
1635  *  format( identifier, const expression, const expression )
1636  *  format_arg( const expression )
1637  *  tls_model( string literal )
1638  *  visibility( string literal )
1639  *  regparm( const expression )
1640  *  model( string leteral )
1641  *  trap_exit( const expression )
1642  *  sp_switch( string literal )
1643  *
1644  * The following attributes might have arguments
1645  *  weak_ref( string literal )
1646  *  non_null( const expression // ',' )
1647  *  interrupt( string literal )
1648  *  sentinel( constant expression )
1649  */
1650 static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
1651 {
1652         gnu_attribute_t *head      = *attributes;
1653         gnu_attribute_t *last      = *attributes;
1654         decl_modifiers_t modifiers = 0;
1655         gnu_attribute_t *attribute;
1656
1657         eat(T___attribute__);
1658         expect('(');
1659         expect('(');
1660
1661         if (token.type != ')') {
1662                 /* find the end of the list */
1663                 if (last != NULL) {
1664                         while (last->next != NULL)
1665                                 last = last->next;
1666                 }
1667
1668                 /* non-empty attribute list */
1669                 while (true) {
1670                         const char *name;
1671                         if (token.type == T_const) {
1672                                 name = "const";
1673                         } else if (token.type == T_volatile) {
1674                                 name = "volatile";
1675                         } else if (token.type == T_cdecl) {
1676                                 /* __attribute__((cdecl)), WITH ms mode */
1677                                 name = "cdecl";
1678                         } else if (token.type == T_IDENTIFIER) {
1679                                 const symbol_t *sym = token.v.symbol;
1680                                 name = sym->string;
1681                         } else {
1682                                 parse_error_expected("while parsing GNU attribute", T_IDENTIFIER, NULL);
1683                                 break;
1684                         }
1685
1686                         next_token();
1687
1688                         int i;
1689                         for(i = 0; i < GNU_AK_LAST; ++i) {
1690                                 if (strcmp_underscore(gnu_attribute_names[i], name) == 0)
1691                                         break;
1692                         }
1693                         gnu_attribute_kind_t kind = (gnu_attribute_kind_t)i;
1694
1695                         attribute = NULL;
1696                         if (kind == GNU_AK_LAST) {
1697                                 if (warning.attribute)
1698                                         warningf(HERE, "'%s' attribute directive ignored", name);
1699
1700                                 /* skip possible arguments */
1701                                 if (token.type == '(') {
1702                                         eat_until_matching_token(')');
1703                                 }
1704                         } else {
1705                                 /* check for arguments */
1706                                 attribute = allocate_gnu_attribute(kind);
1707                                 if (token.type == '(') {
1708                                         next_token();
1709                                         if (token.type == ')') {
1710                                                 /* empty args are allowed */
1711                                                 next_token();
1712                                         } else
1713                                                 attribute->have_arguments = true;
1714                                 }
1715
1716                                 switch(kind) {
1717                                 case GNU_AK_VOLATILE:
1718                                 case GNU_AK_NAKED:
1719                                 case GNU_AK_MALLOC:
1720                                 case GNU_AK_WEAK:
1721                                 case GNU_AK_COMMON:
1722                                 case GNU_AK_NOCOMMON:
1723                                 case GNU_AK_SHARED:
1724                                 case GNU_AK_NOTSHARED:
1725                                 case GNU_AK_NO_INSTRUMENT_FUNCTION:
1726                                 case GNU_AK_WARN_UNUSED_RESULT:
1727                                 case GNU_AK_LONGCALL:
1728                                 case GNU_AK_SHORTCALL:
1729                                 case GNU_AK_LONG_CALL:
1730                                 case GNU_AK_SHORT_CALL:
1731                                 case GNU_AK_FUNCTION_VECTOR:
1732                                 case GNU_AK_INTERRUPT_HANDLER:
1733                                 case GNU_AK_NMI_HANDLER:
1734                                 case GNU_AK_NESTING:
1735                                 case GNU_AK_NEAR:
1736                                 case GNU_AK_FAR:
1737                                 case GNU_AK_SIGNAL:
1738                                 case GNU_AK_EIGTHBIT_DATA:
1739                                 case GNU_AK_TINY_DATA:
1740                                 case GNU_AK_SAVEALL:
1741                                 case GNU_AK_FLATTEN:
1742                                 case GNU_AK_SSEREGPARM:
1743                                 case GNU_AK_EXTERNALLY_VISIBLE:
1744                                 case GNU_AK_RETURN_TWICE:
1745                                 case GNU_AK_MAY_ALIAS:
1746                                 case GNU_AK_MS_STRUCT:
1747                                 case GNU_AK_GCC_STRUCT:
1748                                         goto no_arg;
1749
1750                                 case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
1751                                 case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
1752                                 case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
1753                                 case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
1754                                 case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
1755                                 case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
1756                                 case GNU_AK_CONST:             modifiers |= DM_CONST;             goto no_arg;
1757                                 case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
1758                                 case GNU_AK_DLLIMPORT:         modifiers |= DM_DLLIMPORT;         goto no_arg;
1759                                 case GNU_AK_DLLEXPORT:         modifiers |= DM_DLLEXPORT;         goto no_arg;
1760                                 case GNU_AK_PACKED:            modifiers |= DM_PACKED;            goto no_arg;
1761                                 case GNU_AK_NOINLINE:          modifiers |= DM_NOINLINE;          goto no_arg;
1762                                 case GNU_AK_NORETURN:          modifiers |= DM_NORETURN;          goto no_arg;
1763                                 case GNU_AK_NOTHROW:           modifiers |= DM_NOTHROW;           goto no_arg;
1764                                 case GNU_AK_TRANSPARENT_UNION: modifiers |= DM_TRANSPARENT_UNION; goto no_arg;
1765                                 case GNU_AK_CONSTRUCTOR:       modifiers |= DM_CONSTRUCTOR;       goto no_arg;
1766                                 case GNU_AK_DESTRUCTOR:        modifiers |= DM_DESTRUCTOR;        goto no_arg;
1767                                 case GNU_AK_DEPRECATED:        modifiers |= DM_DEPRECATED;        goto no_arg;
1768
1769                                 case GNU_AK_ALIGNED:
1770                                         /* __align__ may be used without an argument */
1771                                         if (attribute->have_arguments) {
1772                                                 parse_gnu_attribute_const_arg(attribute);
1773                                         }
1774                                         break;
1775
1776                                 case GNU_AK_FORMAT_ARG:
1777                                 case GNU_AK_REGPARM:
1778                                 case GNU_AK_TRAP_EXIT:
1779                                         if (!attribute->have_arguments) {
1780                                                 /* should have arguments */
1781                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1782                                                 attribute->invalid = true;
1783                                         } else
1784                                                 parse_gnu_attribute_const_arg(attribute);
1785                                         break;
1786                                 case GNU_AK_ALIAS:
1787                                 case GNU_AK_SECTION:
1788                                 case GNU_AK_SP_SWITCH:
1789                                         if (!attribute->have_arguments) {
1790                                                 /* should have arguments */
1791                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1792                                                 attribute->invalid = true;
1793                                         } else
1794                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1795                                         break;
1796                                 case GNU_AK_FORMAT:
1797                                         if (!attribute->have_arguments) {
1798                                                 /* should have arguments */
1799                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1800                                                 attribute->invalid = true;
1801                                         } else
1802                                                 parse_gnu_attribute_format_args(attribute);
1803                                         break;
1804                                 case GNU_AK_WEAKREF:
1805                                         /* may have one string argument */
1806                                         if (attribute->have_arguments)
1807                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1808                                         break;
1809                                 case GNU_AK_NONNULL:
1810                                         if (attribute->have_arguments)
1811                                                 parse_gnu_attribute_const_arg_list(attribute);
1812                                         break;
1813                                 case GNU_AK_TLS_MODEL:
1814                                         if (!attribute->have_arguments) {
1815                                                 /* should have arguments */
1816                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1817                                         } else
1818                                                 parse_gnu_attribute_tls_model_arg(attribute);
1819                                         break;
1820                                 case GNU_AK_VISIBILITY:
1821                                         if (!attribute->have_arguments) {
1822                                                 /* should have arguments */
1823                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1824                                         } else
1825                                                 parse_gnu_attribute_visibility_arg(attribute);
1826                                         break;
1827                                 case GNU_AK_MODEL:
1828                                         if (!attribute->have_arguments) {
1829                                                 /* should have arguments */
1830                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1831                                         } else {
1832                                                 parse_gnu_attribute_model_arg(attribute);
1833                                         }
1834                                         break;
1835                                 case GNU_AK_MODE:
1836                                         if (!attribute->have_arguments) {
1837                                                 /* should have arguments */
1838                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1839                                         } else {
1840                                                 parse_gnu_attribute_mode_arg(attribute);
1841                                         }
1842                                         break;
1843                                 case GNU_AK_INTERRUPT:
1844                                         /* may have one string argument */
1845                                         if (attribute->have_arguments)
1846                                                 parse_gnu_attribute_interrupt_arg(attribute);
1847                                         break;
1848                                 case GNU_AK_SENTINEL:
1849                                         /* may have one string argument */
1850                                         if (attribute->have_arguments)
1851                                                 parse_gnu_attribute_const_arg(attribute);
1852                                         break;
1853                                 case GNU_AK_LAST:
1854                                         /* already handled */
1855                                         break;
1856
1857 no_arg:
1858                                         check_no_argument(attribute, name);
1859                                 }
1860                         }
1861                         if (attribute != NULL) {
1862                                 if (last != NULL) {
1863                                         last->next = attribute;
1864                                         last       = attribute;
1865                                 } else {
1866                                         head = last = attribute;
1867                                 }
1868                         }
1869
1870                         if (token.type != ',')
1871                                 break;
1872                         next_token();
1873                 }
1874         }
1875         expect(')');
1876         expect(')');
1877 end_error:
1878         *attributes = head;
1879
1880         return modifiers;
1881 }
1882
1883 /**
1884  * Parse GNU attributes.
1885  */
1886 static decl_modifiers_t parse_attributes(gnu_attribute_t **attributes)
1887 {
1888         decl_modifiers_t modifiers = 0;
1889
1890         while (true) {
1891                 switch(token.type) {
1892                 case T___attribute__:
1893                         modifiers |= parse_gnu_attribute(attributes);
1894                         continue;
1895
1896                 case T_asm:
1897                         next_token();
1898                         expect('(');
1899                         if (token.type != T_STRING_LITERAL) {
1900                                 parse_error_expected("while parsing assembler attribute",
1901                                                      T_STRING_LITERAL, NULL);
1902                                 eat_until_matching_token('(');
1903                                 break;
1904                         } else {
1905                                 parse_string_literals();
1906                         }
1907                         expect(')');
1908                         continue;
1909
1910                 case T_cdecl:     modifiers |= DM_CDECL;    break;
1911                 case T__fastcall: modifiers |= DM_FASTCALL; break;
1912                 case T__stdcall:  modifiers |= DM_STDCALL;  break;
1913
1914                 case T___thiscall:
1915                         /* TODO record modifier */
1916                         if (warning.other)
1917                                 warningf(HERE, "Ignoring declaration modifier %K", &token);
1918                         break;
1919
1920 end_error:
1921                 default: return modifiers;
1922                 }
1923
1924                 next_token();
1925         }
1926 }
1927
1928 static void mark_decls_read(expression_t *expr, declaration_t *lhs_decl);
1929
1930 static declaration_t *determine_lhs_decl(expression_t *const expr, declaration_t *lhs_decl)
1931 {
1932         switch (expr->kind) {
1933                 case EXPR_REFERENCE: {
1934                         declaration_t *const decl = expr->reference.declaration;
1935                         return decl;
1936                 }
1937
1938                 case EXPR_ARRAY_ACCESS: {
1939                         expression_t  *const ref  = expr->array_access.array_ref;
1940                         declaration_t *      decl = NULL;
1941                         if (is_type_array(skip_typeref(revert_automatic_type_conversion(ref)))) {
1942                                 decl     = determine_lhs_decl(ref, lhs_decl);
1943                                 lhs_decl = decl;
1944                         } else {
1945                                 mark_decls_read(expr->select.compound, lhs_decl);
1946                         }
1947                         mark_decls_read(expr->array_access.index, lhs_decl);
1948                         return decl;
1949                 }
1950
1951                 case EXPR_SELECT: {
1952                         if (is_type_compound(skip_typeref(expr->base.type))) {
1953                                 return determine_lhs_decl(expr->select.compound, lhs_decl);
1954                         } else {
1955                                 mark_decls_read(expr->select.compound, lhs_decl);
1956                                 return NULL;
1957                         }
1958                 }
1959
1960                 case EXPR_UNARY_DEREFERENCE: {
1961                         expression_t *const val = expr->unary.value;
1962                         if (val->kind == EXPR_UNARY_TAKE_ADDRESS) {
1963                                 /* *&x is a NOP */
1964                                 return determine_lhs_decl(val->unary.value, lhs_decl);
1965                         } else {
1966                                 mark_decls_read(val, NULL);
1967                                 return NULL;
1968                         }
1969                 }
1970
1971                 default:
1972                         mark_decls_read(expr, NULL);
1973                         return NULL;
1974         }
1975 }
1976
1977 #define DECL_ANY ((declaration_t*)-1)
1978
1979 /**
1980  * Mark declarations, which are read.  This is used to deted variables, which
1981  * are never read.
1982  * Example:
1983  * x = x + 1;
1984  *   x is not marked as "read", because it is only read to calculate its own new
1985  *   value.
1986  *
1987  * x += y; y += x;
1988  *   x and y are not detected as "not read", because multiple variables are
1989  *   involved.
1990  */
1991 static void mark_decls_read(expression_t *const expr, declaration_t *lhs_decl)
1992 {
1993         switch (expr->kind) {
1994                 case EXPR_REFERENCE: {
1995                         declaration_t *const decl = expr->reference.declaration;
1996                         if (lhs_decl != decl && lhs_decl != DECL_ANY)
1997                                 decl->read = true;
1998                         return;
1999                 }
2000
2001                 case EXPR_CALL:
2002                         // TODO respect pure/const
2003                         mark_decls_read(expr->call.function, NULL);
2004                         for (call_argument_t *arg = expr->call.arguments; arg != NULL; arg = arg->next) {
2005                                 mark_decls_read(arg->expression, NULL);
2006                         }
2007                         return;
2008
2009                 case EXPR_CONDITIONAL:
2010                         // TODO lhs_decl should depend on whether true/false have an effect
2011                         mark_decls_read(expr->conditional.condition, NULL);
2012                         if (expr->conditional.true_expression != NULL)
2013                                 mark_decls_read(expr->conditional.true_expression, lhs_decl);
2014                         mark_decls_read(expr->conditional.false_expression, lhs_decl);
2015                         return;
2016
2017                 case EXPR_SELECT:
2018                         if (lhs_decl == DECL_ANY && !is_type_compound(skip_typeref(expr->base.type)))
2019                                 lhs_decl = NULL;
2020                         mark_decls_read(expr->select.compound, lhs_decl);
2021                         return;
2022
2023                 case EXPR_ARRAY_ACCESS: {
2024                         expression_t *const ref = expr->array_access.array_ref;
2025                         mark_decls_read(ref, lhs_decl);
2026                         lhs_decl = determine_lhs_decl(ref, lhs_decl);
2027                         mark_decls_read(expr->array_access.index, lhs_decl);
2028                         return;
2029                 }
2030
2031                 case EXPR_VA_ARG:
2032                         mark_decls_read(expr->va_arge.ap, lhs_decl);
2033                         return;
2034
2035                 case EXPR_UNARY_CAST:
2036                         /* Special case: Use void cast to mark a variable as "read" */
2037                         if (is_type_atomic(skip_typeref(expr->base.type), ATOMIC_TYPE_VOID))
2038                                 lhs_decl = NULL;
2039                         goto unary;
2040
2041                 case EXPR_UNARY_DEREFERENCE:
2042                         if (lhs_decl == DECL_ANY)
2043                                 lhs_decl = NULL;
2044                         goto unary;
2045
2046                 case EXPR_UNARY_THROW:
2047                         if (expr->unary.value == NULL)
2048                                 return;
2049                         goto unary;
2050
2051                 case EXPR_UNARY_NEGATE:
2052                 case EXPR_UNARY_PLUS:
2053                 case EXPR_UNARY_BITWISE_NEGATE:
2054                 case EXPR_UNARY_NOT:
2055                 case EXPR_UNARY_TAKE_ADDRESS:
2056                 case EXPR_UNARY_POSTFIX_INCREMENT:
2057                 case EXPR_UNARY_POSTFIX_DECREMENT:
2058                 case EXPR_UNARY_PREFIX_INCREMENT:
2059                 case EXPR_UNARY_PREFIX_DECREMENT:
2060                 case EXPR_UNARY_CAST_IMPLICIT:
2061                 case EXPR_UNARY_ASSUME:
2062 unary:
2063                         mark_decls_read(expr->unary.value, lhs_decl);
2064                         return;
2065
2066                 case EXPR_BINARY_ADD:
2067                 case EXPR_BINARY_SUB:
2068                 case EXPR_BINARY_MUL:
2069                 case EXPR_BINARY_DIV:
2070                 case EXPR_BINARY_MOD:
2071                 case EXPR_BINARY_EQUAL:
2072                 case EXPR_BINARY_NOTEQUAL:
2073                 case EXPR_BINARY_LESS:
2074                 case EXPR_BINARY_LESSEQUAL:
2075                 case EXPR_BINARY_GREATER:
2076                 case EXPR_BINARY_GREATEREQUAL:
2077                 case EXPR_BINARY_BITWISE_AND:
2078                 case EXPR_BINARY_BITWISE_OR:
2079                 case EXPR_BINARY_BITWISE_XOR:
2080                 case EXPR_BINARY_LOGICAL_AND:
2081                 case EXPR_BINARY_LOGICAL_OR:
2082                 case EXPR_BINARY_SHIFTLEFT:
2083                 case EXPR_BINARY_SHIFTRIGHT:
2084                 case EXPR_BINARY_COMMA:
2085                 case EXPR_BINARY_ISGREATER:
2086                 case EXPR_BINARY_ISGREATEREQUAL:
2087                 case EXPR_BINARY_ISLESS:
2088                 case EXPR_BINARY_ISLESSEQUAL:
2089                 case EXPR_BINARY_ISLESSGREATER:
2090                 case EXPR_BINARY_ISUNORDERED:
2091                         mark_decls_read(expr->binary.left,  lhs_decl);
2092                         mark_decls_read(expr->binary.right, lhs_decl);
2093                         return;
2094
2095                 case EXPR_BINARY_ASSIGN:
2096                 case EXPR_BINARY_MUL_ASSIGN:
2097                 case EXPR_BINARY_DIV_ASSIGN:
2098                 case EXPR_BINARY_MOD_ASSIGN:
2099                 case EXPR_BINARY_ADD_ASSIGN:
2100                 case EXPR_BINARY_SUB_ASSIGN:
2101                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:
2102                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:
2103                 case EXPR_BINARY_BITWISE_AND_ASSIGN:
2104                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:
2105                 case EXPR_BINARY_BITWISE_OR_ASSIGN: {
2106                         if (lhs_decl == DECL_ANY)
2107                                 lhs_decl = NULL;
2108                         lhs_decl = determine_lhs_decl(expr->binary.left, lhs_decl);
2109                         mark_decls_read(expr->binary.right, lhs_decl);
2110                         return;
2111                 }
2112
2113                 case EXPR_VA_START:
2114                         determine_lhs_decl(expr->va_starte.ap, lhs_decl);
2115                         return;
2116
2117                 case EXPR_UNKNOWN:
2118                 case EXPR_INVALID:
2119                 case EXPR_CONST:
2120                 case EXPR_CHARACTER_CONSTANT:
2121                 case EXPR_WIDE_CHARACTER_CONSTANT:
2122                 case EXPR_STRING_LITERAL:
2123                 case EXPR_WIDE_STRING_LITERAL:
2124                 case EXPR_COMPOUND_LITERAL: // TODO init?
2125                 case EXPR_SIZEOF:
2126                 case EXPR_CLASSIFY_TYPE:
2127                 case EXPR_ALIGNOF:
2128                 case EXPR_FUNCNAME:
2129                 case EXPR_BUILTIN_SYMBOL:
2130                 case EXPR_BUILTIN_CONSTANT_P:
2131                 case EXPR_BUILTIN_PREFETCH:
2132                 case EXPR_OFFSETOF:
2133                 case EXPR_STATEMENT: // TODO
2134                 case EXPR_LABEL_ADDRESS:
2135                 case EXPR_BINARY_BUILTIN_EXPECT:
2136                         return;
2137         }
2138
2139         panic("unhandled expression");
2140 }
2141
2142 static designator_t *parse_designation(void)
2143 {
2144         designator_t *result = NULL;
2145         designator_t *last   = NULL;
2146
2147         while (true) {
2148                 designator_t *designator;
2149                 switch(token.type) {
2150                 case '[':
2151                         designator = allocate_ast_zero(sizeof(designator[0]));
2152                         designator->source_position = token.source_position;
2153                         next_token();
2154                         add_anchor_token(']');
2155                         designator->array_index = parse_constant_expression();
2156                         rem_anchor_token(']');
2157                         expect(']');
2158                         break;
2159                 case '.':
2160                         designator = allocate_ast_zero(sizeof(designator[0]));
2161                         designator->source_position = token.source_position;
2162                         next_token();
2163                         if (token.type != T_IDENTIFIER) {
2164                                 parse_error_expected("while parsing designator",
2165                                                      T_IDENTIFIER, NULL);
2166                                 return NULL;
2167                         }
2168                         designator->symbol = token.v.symbol;
2169                         next_token();
2170                         break;
2171                 default:
2172                         expect('=');
2173                         return result;
2174                 }
2175
2176                 assert(designator != NULL);
2177                 if (last != NULL) {
2178                         last->next = designator;
2179                 } else {
2180                         result = designator;
2181                 }
2182                 last = designator;
2183         }
2184 end_error:
2185         return NULL;
2186 }
2187
2188 static initializer_t *initializer_from_string(array_type_t *type,
2189                                               const string_t *const string)
2190 {
2191         /* TODO: check len vs. size of array type */
2192         (void) type;
2193
2194         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
2195         initializer->string.string = *string;
2196
2197         return initializer;
2198 }
2199
2200 static initializer_t *initializer_from_wide_string(array_type_t *const type,
2201                                                    wide_string_t *const string)
2202 {
2203         /* TODO: check len vs. size of array type */
2204         (void) type;
2205
2206         initializer_t *const initializer =
2207                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
2208         initializer->wide_string.string = *string;
2209
2210         return initializer;
2211 }
2212
2213 /**
2214  * Build an initializer from a given expression.
2215  */
2216 static initializer_t *initializer_from_expression(type_t *orig_type,
2217                                                   expression_t *expression)
2218 {
2219         /* TODO check that expression is a constant expression */
2220
2221         /* § 6.7.8.14/15 char array may be initialized by string literals */
2222         type_t *type           = skip_typeref(orig_type);
2223         type_t *expr_type_orig = expression->base.type;
2224         type_t *expr_type      = skip_typeref(expr_type_orig);
2225         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
2226                 array_type_t *const array_type   = &type->array;
2227                 type_t       *const element_type = skip_typeref(array_type->element_type);
2228
2229                 if (element_type->kind == TYPE_ATOMIC) {
2230                         atomic_type_kind_t akind = element_type->atomic.akind;
2231                         switch (expression->kind) {
2232                                 case EXPR_STRING_LITERAL:
2233                                         if (akind == ATOMIC_TYPE_CHAR
2234                                                         || akind == ATOMIC_TYPE_SCHAR
2235                                                         || akind == ATOMIC_TYPE_UCHAR) {
2236                                                 return initializer_from_string(array_type,
2237                                                         &expression->string.value);
2238                                         }
2239
2240                                 case EXPR_WIDE_STRING_LITERAL: {
2241                                         type_t *bare_wchar_type = skip_typeref(type_wchar_t);
2242                                         if (get_unqualified_type(element_type) == bare_wchar_type) {
2243                                                 return initializer_from_wide_string(array_type,
2244                                                         &expression->wide_string.value);
2245                                         }
2246                                 }
2247
2248                                 default:
2249                                         break;
2250                         }
2251                 }
2252         }
2253
2254         assign_error_t error = semantic_assign(type, expression);
2255         if (error == ASSIGN_ERROR_INCOMPATIBLE)
2256                 return NULL;
2257         report_assign_error(error, type, expression, "initializer",
2258                             &expression->base.source_position);
2259
2260         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
2261 #if 0
2262         if (type->kind == TYPE_BITFIELD) {
2263                 type = type->bitfield.base_type;
2264         }
2265 #endif
2266         result->value.value = create_implicit_cast(expression, type);
2267
2268         return result;
2269 }
2270
2271 /**
2272  * Checks if a given expression can be used as an constant initializer.
2273  */
2274 static bool is_initializer_constant(const expression_t *expression)
2275 {
2276         return is_constant_expression(expression)
2277                 || is_address_constant(expression);
2278 }
2279
2280 /**
2281  * Parses an scalar initializer.
2282  *
2283  * § 6.7.8.11; eat {} without warning
2284  */
2285 static initializer_t *parse_scalar_initializer(type_t *type,
2286                                                bool must_be_constant)
2287 {
2288         /* there might be extra {} hierarchies */
2289         int braces = 0;
2290         if (token.type == '{') {
2291                 if (warning.other)
2292                         warningf(HERE, "extra curly braces around scalar initializer");
2293                 do {
2294                         ++braces;
2295                         next_token();
2296                 } while (token.type == '{');
2297         }
2298
2299         expression_t *expression = parse_assignment_expression();
2300         mark_decls_read(expression, NULL);
2301         if (must_be_constant && !is_initializer_constant(expression)) {
2302                 errorf(&expression->base.source_position,
2303                        "Initialisation expression '%E' is not constant\n",
2304                        expression);
2305         }
2306
2307         initializer_t *initializer = initializer_from_expression(type, expression);
2308
2309         if (initializer == NULL) {
2310                 errorf(&expression->base.source_position,
2311                        "expression '%E' (type '%T') doesn't match expected type '%T'",
2312                        expression, expression->base.type, type);
2313                 /* TODO */
2314                 return NULL;
2315         }
2316
2317         bool additional_warning_displayed = false;
2318         while (braces > 0) {
2319                 if (token.type == ',') {
2320                         next_token();
2321                 }
2322                 if (token.type != '}') {
2323                         if (!additional_warning_displayed && warning.other) {
2324                                 warningf(HERE, "additional elements in scalar initializer");
2325                                 additional_warning_displayed = true;
2326                         }
2327                 }
2328                 eat_block();
2329                 braces--;
2330         }
2331
2332         return initializer;
2333 }
2334
2335 /**
2336  * An entry in the type path.
2337  */
2338 typedef struct type_path_entry_t type_path_entry_t;
2339 struct type_path_entry_t {
2340         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
2341         union {
2342                 size_t         index;          /**< For array types: the current index. */
2343                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
2344         } v;
2345 };
2346
2347 /**
2348  * A type path expression a position inside compound or array types.
2349  */
2350 typedef struct type_path_t type_path_t;
2351 struct type_path_t {
2352         type_path_entry_t *path;         /**< An flexible array containing the current path. */
2353         type_t            *top_type;     /**< type of the element the path points */
2354         size_t             max_index;    /**< largest index in outermost array */
2355 };
2356
2357 /**
2358  * Prints a type path for debugging.
2359  */
2360 static __attribute__((unused)) void debug_print_type_path(
2361                 const type_path_t *path)
2362 {
2363         size_t len = ARR_LEN(path->path);
2364
2365         for(size_t i = 0; i < len; ++i) {
2366                 const type_path_entry_t *entry = & path->path[i];
2367
2368                 type_t *type = skip_typeref(entry->type);
2369                 if (is_type_compound(type)) {
2370                         /* in gcc mode structs can have no members */
2371                         if (entry->v.compound_entry == NULL) {
2372                                 assert(i == len-1);
2373                                 continue;
2374                         }
2375                         fprintf(stderr, ".%s", entry->v.compound_entry->symbol->string);
2376                 } else if (is_type_array(type)) {
2377                         fprintf(stderr, "[%zu]", entry->v.index);
2378                 } else {
2379                         fprintf(stderr, "-INVALID-");
2380                 }
2381         }
2382         if (path->top_type != NULL) {
2383                 fprintf(stderr, "  (");
2384                 print_type(path->top_type);
2385                 fprintf(stderr, ")");
2386         }
2387 }
2388
2389 /**
2390  * Return the top type path entry, ie. in a path
2391  * (type).a.b returns the b.
2392  */
2393 static type_path_entry_t *get_type_path_top(const type_path_t *path)
2394 {
2395         size_t len = ARR_LEN(path->path);
2396         assert(len > 0);
2397         return &path->path[len-1];
2398 }
2399
2400 /**
2401  * Enlarge the type path by an (empty) element.
2402  */
2403 static type_path_entry_t *append_to_type_path(type_path_t *path)
2404 {
2405         size_t len = ARR_LEN(path->path);
2406         ARR_RESIZE(type_path_entry_t, path->path, len+1);
2407
2408         type_path_entry_t *result = & path->path[len];
2409         memset(result, 0, sizeof(result[0]));
2410         return result;
2411 }
2412
2413 /**
2414  * Descending into a sub-type. Enter the scope of the current
2415  * top_type.
2416  */
2417 static void descend_into_subtype(type_path_t *path)
2418 {
2419         type_t *orig_top_type = path->top_type;
2420         type_t *top_type      = skip_typeref(orig_top_type);
2421
2422         type_path_entry_t *top = append_to_type_path(path);
2423         top->type              = top_type;
2424
2425         if (is_type_compound(top_type)) {
2426                 declaration_t *declaration = top_type->compound.declaration;
2427                 declaration_t *entry       = declaration->scope.declarations;
2428                 top->v.compound_entry      = entry;
2429
2430                 if (entry != NULL) {
2431                         path->top_type         = entry->type;
2432                 } else {
2433                         path->top_type         = NULL;
2434                 }
2435         } else if (is_type_array(top_type)) {
2436                 top->v.index   = 0;
2437                 path->top_type = top_type->array.element_type;
2438         } else {
2439                 assert(!is_type_valid(top_type));
2440         }
2441 }
2442
2443 /**
2444  * Pop an entry from the given type path, ie. returning from
2445  * (type).a.b to (type).a
2446  */
2447 static void ascend_from_subtype(type_path_t *path)
2448 {
2449         type_path_entry_t *top = get_type_path_top(path);
2450
2451         path->top_type = top->type;
2452
2453         size_t len = ARR_LEN(path->path);
2454         ARR_RESIZE(type_path_entry_t, path->path, len-1);
2455 }
2456
2457 /**
2458  * Pop entries from the given type path until the given
2459  * path level is reached.
2460  */
2461 static void ascend_to(type_path_t *path, size_t top_path_level)
2462 {
2463         size_t len = ARR_LEN(path->path);
2464
2465         while (len > top_path_level) {
2466                 ascend_from_subtype(path);
2467                 len = ARR_LEN(path->path);
2468         }
2469 }
2470
2471 static bool walk_designator(type_path_t *path, const designator_t *designator,
2472                             bool used_in_offsetof)
2473 {
2474         for( ; designator != NULL; designator = designator->next) {
2475                 type_path_entry_t *top       = get_type_path_top(path);
2476                 type_t            *orig_type = top->type;
2477
2478                 type_t *type = skip_typeref(orig_type);
2479
2480                 if (designator->symbol != NULL) {
2481                         symbol_t *symbol = designator->symbol;
2482                         if (!is_type_compound(type)) {
2483                                 if (is_type_valid(type)) {
2484                                         errorf(&designator->source_position,
2485                                                "'.%Y' designator used for non-compound type '%T'",
2486                                                symbol, orig_type);
2487                                 }
2488
2489                                 top->type             = type_error_type;
2490                                 top->v.compound_entry = NULL;
2491                                 orig_type             = type_error_type;
2492                         } else {
2493                                 declaration_t *declaration = type->compound.declaration;
2494                                 declaration_t *iter        = declaration->scope.declarations;
2495                                 for( ; iter != NULL; iter = iter->next) {
2496                                         if (iter->symbol == symbol) {
2497                                                 break;
2498                                         }
2499                                 }
2500                                 if (iter == NULL) {
2501                                         errorf(&designator->source_position,
2502                                                "'%T' has no member named '%Y'", orig_type, symbol);
2503                                         goto failed;
2504                                 }
2505                                 if (used_in_offsetof) {
2506                                         type_t *real_type = skip_typeref(iter->type);
2507                                         if (real_type->kind == TYPE_BITFIELD) {
2508                                                 errorf(&designator->source_position,
2509                                                        "offsetof designator '%Y' may not specify bitfield",
2510                                                        symbol);
2511                                                 goto failed;
2512                                         }
2513                                 }
2514
2515                                 top->type             = orig_type;
2516                                 top->v.compound_entry = iter;
2517                                 orig_type             = iter->type;
2518                         }
2519                 } else {
2520                         expression_t *array_index = designator->array_index;
2521                         assert(designator->array_index != NULL);
2522
2523                         if (!is_type_array(type)) {
2524                                 if (is_type_valid(type)) {
2525                                         errorf(&designator->source_position,
2526                                                "[%E] designator used for non-array type '%T'",
2527                                                array_index, orig_type);
2528                                 }
2529                                 goto failed;
2530                         }
2531
2532                         long index = fold_constant(array_index);
2533                         if (!used_in_offsetof) {
2534                                 if (index < 0) {
2535                                         errorf(&designator->source_position,
2536                                                "array index [%E] must be positive", array_index);
2537                                 } else if (type->array.size_constant) {
2538                                         long array_size = type->array.size;
2539                                         if (index >= array_size) {
2540                                                 errorf(&designator->source_position,
2541                                                        "designator [%E] (%d) exceeds array size %d",
2542                                                        array_index, index, array_size);
2543                                         }
2544                                 }
2545                         }
2546
2547                         top->type    = orig_type;
2548                         top->v.index = (size_t) index;
2549                         orig_type    = type->array.element_type;
2550                 }
2551                 path->top_type = orig_type;
2552
2553                 if (designator->next != NULL) {
2554                         descend_into_subtype(path);
2555                 }
2556         }
2557         return true;
2558
2559 failed:
2560         return false;
2561 }
2562
2563 static void advance_current_object(type_path_t *path, size_t top_path_level)
2564 {
2565         type_path_entry_t *top = get_type_path_top(path);
2566
2567         type_t *type = skip_typeref(top->type);
2568         if (is_type_union(type)) {
2569                 /* in unions only the first element is initialized */
2570                 top->v.compound_entry = NULL;
2571         } else if (is_type_struct(type)) {
2572                 declaration_t *entry = top->v.compound_entry;
2573
2574                 entry                 = entry->next;
2575                 top->v.compound_entry = entry;
2576                 if (entry != NULL) {
2577                         path->top_type = entry->type;
2578                         return;
2579                 }
2580         } else if (is_type_array(type)) {
2581                 assert(is_type_array(type));
2582
2583                 top->v.index++;
2584
2585                 if (!type->array.size_constant || top->v.index < type->array.size) {
2586                         return;
2587                 }
2588         } else {
2589                 assert(!is_type_valid(type));
2590                 return;
2591         }
2592
2593         /* we're past the last member of the current sub-aggregate, try if we
2594          * can ascend in the type hierarchy and continue with another subobject */
2595         size_t len = ARR_LEN(path->path);
2596
2597         if (len > top_path_level) {
2598                 ascend_from_subtype(path);
2599                 advance_current_object(path, top_path_level);
2600         } else {
2601                 path->top_type = NULL;
2602         }
2603 }
2604
2605 /**
2606  * skip until token is found.
2607  */
2608 static void skip_until(int type)
2609 {
2610         while (token.type != type) {
2611                 if (token.type == T_EOF)
2612                         return;
2613                 next_token();
2614         }
2615 }
2616
2617 /**
2618  * skip any {...} blocks until a closing bracket is reached.
2619  */
2620 static void skip_initializers(void)
2621 {
2622         if (token.type == '{')
2623                 next_token();
2624
2625         while (token.type != '}') {
2626                 if (token.type == T_EOF)
2627                         return;
2628                 if (token.type == '{') {
2629                         eat_block();
2630                         continue;
2631                 }
2632                 next_token();
2633         }
2634 }
2635
2636 static initializer_t *create_empty_initializer(void)
2637 {
2638         static initializer_t empty_initializer
2639                 = { .list = { { INITIALIZER_LIST }, 0 } };
2640         return &empty_initializer;
2641 }
2642
2643 /**
2644  * Parse a part of an initialiser for a struct or union,
2645  */
2646 static initializer_t *parse_sub_initializer(type_path_t *path,
2647                 type_t *outer_type, size_t top_path_level,
2648                 parse_initializer_env_t *env)
2649 {
2650         if (token.type == '}') {
2651                 /* empty initializer */
2652                 return create_empty_initializer();
2653         }
2654
2655         type_t *orig_type = path->top_type;
2656         type_t *type      = NULL;
2657
2658         if (orig_type == NULL) {
2659                 /* We are initializing an empty compound. */
2660         } else {
2661                 type = skip_typeref(orig_type);
2662         }
2663
2664         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2665
2666         while (true) {
2667                 designator_t *designator = NULL;
2668                 if (token.type == '.' || token.type == '[') {
2669                         designator = parse_designation();
2670                         goto finish_designator;
2671                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2672                         /* GNU-style designator ("identifier: value") */
2673                         designator = allocate_ast_zero(sizeof(designator[0]));
2674                         designator->source_position = token.source_position;
2675                         designator->symbol          = token.v.symbol;
2676                         eat(T_IDENTIFIER);
2677                         eat(':');
2678
2679 finish_designator:
2680                         /* reset path to toplevel, evaluate designator from there */
2681                         ascend_to(path, top_path_level);
2682                         if (!walk_designator(path, designator, false)) {
2683                                 /* can't continue after designation error */
2684                                 goto end_error;
2685                         }
2686
2687                         initializer_t *designator_initializer
2688                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2689                         designator_initializer->designator.designator = designator;
2690                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2691
2692                         orig_type = path->top_type;
2693                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2694                 }
2695
2696                 initializer_t *sub;
2697
2698                 if (token.type == '{') {
2699                         if (type != NULL && is_type_scalar(type)) {
2700                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2701                         } else {
2702                                 eat('{');
2703                                 if (type == NULL) {
2704                                         if (env->declaration != NULL) {
2705                                                 errorf(HERE, "extra brace group at end of initializer for '%Y'",
2706                                                        env->declaration->symbol);
2707                                         } else {
2708                                                 errorf(HERE, "extra brace group at end of initializer");
2709                                         }
2710                                 } else
2711                                         descend_into_subtype(path);
2712
2713                                 add_anchor_token('}');
2714                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2715                                                             env);
2716                                 rem_anchor_token('}');
2717
2718                                 if (type != NULL) {
2719                                         ascend_from_subtype(path);
2720                                         expect('}');
2721                                 } else {
2722                                         expect('}');
2723                                         goto error_parse_next;
2724                                 }
2725                         }
2726                 } else {
2727                         /* must be an expression */
2728                         expression_t *expression = parse_assignment_expression();
2729
2730                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2731                                 errorf(&expression->base.source_position,
2732                                        "Initialisation expression '%E' is not constant\n",
2733                                        expression);
2734                         }
2735
2736                         if (type == NULL) {
2737                                 /* we are already outside, ... */
2738                                 type_t *const outer_type_skip = skip_typeref(outer_type);
2739                                 if (is_type_compound(outer_type_skip) &&
2740                                     !outer_type_skip->compound.declaration->init.complete) {
2741                                         goto error_parse_next;
2742                                 }
2743                                 goto error_excess;
2744                         }
2745
2746                         /* handle { "string" } special case */
2747                         if ((expression->kind == EXPR_STRING_LITERAL
2748                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2749                                         && outer_type != NULL) {
2750                                 sub = initializer_from_expression(outer_type, expression);
2751                                 if (sub != NULL) {
2752                                         if (token.type == ',') {
2753                                                 next_token();
2754                                         }
2755                                         if (token.type != '}' && warning.other) {
2756                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2757                                                                  orig_type);
2758                                         }
2759                                         /* TODO: eat , ... */
2760                                         return sub;
2761                                 }
2762                         }
2763
2764                         /* descend into subtypes until expression matches type */
2765                         while (true) {
2766                                 orig_type = path->top_type;
2767                                 type      = skip_typeref(orig_type);
2768
2769                                 sub = initializer_from_expression(orig_type, expression);
2770                                 if (sub != NULL) {
2771                                         break;
2772                                 }
2773                                 if (!is_type_valid(type)) {
2774                                         goto end_error;
2775                                 }
2776                                 if (is_type_scalar(type)) {
2777                                         errorf(&expression->base.source_position,
2778                                                         "expression '%E' doesn't match expected type '%T'",
2779                                                         expression, orig_type);
2780                                         goto end_error;
2781                                 }
2782
2783                                 descend_into_subtype(path);
2784                         }
2785                 }
2786
2787                 /* update largest index of top array */
2788                 const type_path_entry_t *first      = &path->path[0];
2789                 type_t                  *first_type = first->type;
2790                 first_type                          = skip_typeref(first_type);
2791                 if (is_type_array(first_type)) {
2792                         size_t index = first->v.index;
2793                         if (index > path->max_index)
2794                                 path->max_index = index;
2795                 }
2796
2797                 if (type != NULL) {
2798                         /* append to initializers list */
2799                         ARR_APP1(initializer_t*, initializers, sub);
2800                 } else {
2801 error_excess:
2802                         if (warning.other) {
2803                                 if (env->declaration != NULL) {
2804                                         warningf(HERE, "excess elements in struct initializer for '%Y'",
2805                                            env->declaration->symbol);
2806                                 } else {
2807                                         warningf(HERE, "excess elements in struct initializer");
2808                                 }
2809                         }
2810                 }
2811
2812 error_parse_next:
2813                 if (token.type == '}') {
2814                         break;
2815                 }
2816                 expect(',');
2817                 if (token.type == '}') {
2818                         break;
2819                 }
2820
2821                 if (type != NULL) {
2822                         /* advance to the next declaration if we are not at the end */
2823                         advance_current_object(path, top_path_level);
2824                         orig_type = path->top_type;
2825                         if (orig_type != NULL)
2826                                 type = skip_typeref(orig_type);
2827                         else
2828                                 type = NULL;
2829                 }
2830         }
2831
2832         size_t len  = ARR_LEN(initializers);
2833         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2834         initializer_t *result = allocate_ast_zero(size);
2835         result->kind          = INITIALIZER_LIST;
2836         result->list.len      = len;
2837         memcpy(&result->list.initializers, initializers,
2838                len * sizeof(initializers[0]));
2839
2840         DEL_ARR_F(initializers);
2841         ascend_to(path, top_path_level+1);
2842
2843         return result;
2844
2845 end_error:
2846         skip_initializers();
2847         DEL_ARR_F(initializers);
2848         ascend_to(path, top_path_level+1);
2849         return NULL;
2850 }
2851
2852 /**
2853  * Parses an initializer. Parsers either a compound literal
2854  * (env->declaration == NULL) or an initializer of a declaration.
2855  */
2856 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2857 {
2858         type_t        *type   = skip_typeref(env->type);
2859         initializer_t *result = NULL;
2860         size_t         max_index;
2861
2862         if (is_type_scalar(type)) {
2863                 result = parse_scalar_initializer(type, env->must_be_constant);
2864         } else if (token.type == '{') {
2865                 eat('{');
2866
2867                 type_path_t path;
2868                 memset(&path, 0, sizeof(path));
2869                 path.top_type = env->type;
2870                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2871
2872                 descend_into_subtype(&path);
2873
2874                 add_anchor_token('}');
2875                 result = parse_sub_initializer(&path, env->type, 1, env);
2876                 rem_anchor_token('}');
2877
2878                 max_index = path.max_index;
2879                 DEL_ARR_F(path.path);
2880
2881                 expect('}');
2882         } else {
2883                 /* parse_scalar_initializer() also works in this case: we simply
2884                  * have an expression without {} around it */
2885                 result = parse_scalar_initializer(type, env->must_be_constant);
2886         }
2887
2888         /* § 6.7.5 (22)  array initializers for arrays with unknown size determine
2889          * the array type size */
2890         if (is_type_array(type) && type->array.size_expression == NULL
2891                         && result != NULL) {
2892                 size_t size;
2893                 switch (result->kind) {
2894                 case INITIALIZER_LIST:
2895                         size = max_index + 1;
2896                         break;
2897
2898                 case INITIALIZER_STRING:
2899                         size = result->string.string.size;
2900                         break;
2901
2902                 case INITIALIZER_WIDE_STRING:
2903                         size = result->wide_string.string.size;
2904                         break;
2905
2906                 case INITIALIZER_DESIGNATOR:
2907                 case INITIALIZER_VALUE:
2908                         /* can happen for parse errors */
2909                         size = 0;
2910                         break;
2911
2912                 default:
2913                         internal_errorf(HERE, "invalid initializer type");
2914                 }
2915
2916                 expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2917                 cnst->base.type          = type_size_t;
2918                 cnst->conste.v.int_value = size;
2919
2920                 type_t *new_type = duplicate_type(type);
2921
2922                 new_type->array.size_expression = cnst;
2923                 new_type->array.size_constant   = true;
2924                 new_type->array.size            = size;
2925                 env->type = new_type;
2926         }
2927
2928         return result;
2929 end_error:
2930         return NULL;
2931 }
2932
2933 static declaration_t *append_declaration(declaration_t *declaration);
2934
2935 static declaration_t *parse_compound_type_specifier(bool is_struct)
2936 {
2937         gnu_attribute_t  *attributes = NULL;
2938         decl_modifiers_t  modifiers  = 0;
2939         if (is_struct) {
2940                 eat(T_struct);
2941         } else {
2942                 eat(T_union);
2943         }
2944
2945         symbol_t      *symbol      = NULL;
2946         declaration_t *declaration = NULL;
2947
2948         if (token.type == T___attribute__) {
2949                 modifiers |= parse_attributes(&attributes);
2950         }
2951
2952         if (token.type == T_IDENTIFIER) {
2953                 symbol = token.v.symbol;
2954                 next_token();
2955
2956                 namespace_t const namespc =
2957                         is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION;
2958                 declaration = get_declaration(symbol, namespc);
2959                 if (declaration != NULL) {
2960                         if (declaration->parent_scope != scope &&
2961                             (token.type == '{' || token.type == ';')) {
2962                                 declaration = NULL;
2963                         } else if (declaration->init.complete &&
2964                                    token.type == '{') {
2965                                 assert(symbol != NULL);
2966                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition at %P)",
2967                                        is_struct ? "struct" : "union", symbol,
2968                                        &declaration->source_position);
2969                                 declaration->scope.declarations = NULL;
2970                         }
2971                 }
2972         } else if (token.type != '{') {
2973                 if (is_struct) {
2974                         parse_error_expected("while parsing struct type specifier",
2975                                              T_IDENTIFIER, '{', NULL);
2976                 } else {
2977                         parse_error_expected("while parsing union type specifier",
2978                                              T_IDENTIFIER, '{', NULL);
2979                 }
2980
2981                 return NULL;
2982         }
2983
2984         if (declaration == NULL) {
2985                 declaration = allocate_declaration_zero();
2986                 declaration->namespc         =
2987                         (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
2988                 declaration->source_position = token.source_position;
2989                 declaration->symbol          = symbol;
2990                 declaration->parent_scope    = scope;
2991                 if (symbol != NULL) {
2992                         environment_push(declaration);
2993                 }
2994                 append_declaration(declaration);
2995         }
2996
2997         if (token.type == '{') {
2998                 declaration->init.complete = true;
2999
3000                 parse_compound_type_entries(declaration);
3001                 modifiers |= parse_attributes(&attributes);
3002         }
3003
3004         declaration->modifiers |= modifiers;
3005         return declaration;
3006 }
3007
3008 static void parse_enum_entries(type_t *const enum_type)
3009 {
3010         eat('{');
3011
3012         if (token.type == '}') {
3013                 next_token();
3014                 errorf(HERE, "empty enum not allowed");
3015                 return;
3016         }
3017
3018         add_anchor_token('}');
3019         do {
3020                 if (token.type != T_IDENTIFIER) {
3021                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
3022                         eat_block();
3023                         rem_anchor_token('}');
3024                         return;
3025                 }
3026
3027                 declaration_t *const entry = allocate_declaration_zero();
3028                 entry->storage_class   = STORAGE_CLASS_ENUM_ENTRY;
3029                 entry->type            = enum_type;
3030                 entry->symbol          = token.v.symbol;
3031                 entry->source_position = token.source_position;
3032                 next_token();
3033
3034                 if (token.type == '=') {
3035                         next_token();
3036                         expression_t *value = parse_constant_expression();
3037
3038                         value = create_implicit_cast(value, enum_type);
3039                         entry->init.enum_value = value;
3040
3041                         /* TODO semantic */
3042                 }
3043
3044                 record_declaration(entry, false);
3045
3046                 if (token.type != ',')
3047                         break;
3048                 next_token();
3049         } while (token.type != '}');
3050         rem_anchor_token('}');
3051
3052         expect('}');
3053
3054 end_error:
3055         ;
3056 }
3057
3058 static type_t *parse_enum_specifier(void)
3059 {
3060         gnu_attribute_t *attributes = NULL;
3061         declaration_t   *declaration;
3062         symbol_t        *symbol;
3063
3064         eat(T_enum);
3065         if (token.type == T_IDENTIFIER) {
3066                 symbol = token.v.symbol;
3067                 next_token();
3068
3069                 declaration = get_declaration(symbol, NAMESPACE_ENUM);
3070         } else if (token.type != '{') {
3071                 parse_error_expected("while parsing enum type specifier",
3072                                      T_IDENTIFIER, '{', NULL);
3073                 return NULL;
3074         } else {
3075                 declaration = NULL;
3076                 symbol      = NULL;
3077         }
3078
3079         if (declaration == NULL) {
3080                 declaration = allocate_declaration_zero();
3081                 declaration->namespc         = NAMESPACE_ENUM;
3082                 declaration->source_position = token.source_position;
3083                 declaration->symbol          = symbol;
3084                 declaration->parent_scope  = scope;
3085         }
3086
3087         type_t *const type      = allocate_type_zero(TYPE_ENUM);
3088         type->enumt.declaration = declaration;
3089
3090         if (token.type == '{') {
3091                 if (declaration->init.complete) {
3092                         errorf(HERE, "multiple definitions of enum %Y", symbol);
3093                 }
3094                 if (symbol != NULL) {
3095                         environment_push(declaration);
3096                 }
3097                 append_declaration(declaration);
3098                 declaration->init.complete = true;
3099
3100                 parse_enum_entries(type);
3101                 parse_attributes(&attributes);
3102         }
3103
3104         return type;
3105 }
3106
3107 /**
3108  * if a symbol is a typedef to another type, return true
3109  */
3110 static bool is_typedef_symbol(symbol_t *symbol)
3111 {
3112         const declaration_t *const declaration =
3113                 get_declaration(symbol, NAMESPACE_NORMAL);
3114         return
3115                 declaration != NULL &&
3116                 declaration->storage_class == STORAGE_CLASS_TYPEDEF;
3117 }
3118
3119 static type_t *parse_typeof(void)
3120 {
3121         eat(T___typeof__);
3122
3123         type_t *type;
3124
3125         expect('(');
3126         add_anchor_token(')');
3127
3128         expression_t *expression  = NULL;
3129
3130         bool old_type_prop     = in_type_prop;
3131         bool old_gcc_extension = in_gcc_extension;
3132         in_type_prop           = true;
3133
3134         while (token.type == T___extension__) {
3135                 /* This can be a prefix to a typename or an expression. */
3136                 next_token();
3137                 in_gcc_extension = true;
3138         }
3139         switch (token.type) {
3140         case T_IDENTIFIER:
3141                 if (is_typedef_symbol(token.v.symbol)) {
3142                         type = parse_typename();
3143                 } else {
3144                         expression = parse_expression();
3145                         type       = expression->base.type;
3146                 }
3147                 break;
3148
3149         TYPENAME_START
3150                 type = parse_typename();
3151                 break;
3152
3153         default:
3154                 expression = parse_expression();
3155                 type       = expression->base.type;
3156                 break;
3157         }
3158         in_type_prop     = old_type_prop;
3159         in_gcc_extension = old_gcc_extension;
3160
3161         rem_anchor_token(')');
3162         expect(')');
3163
3164         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF);
3165         typeof_type->typeoft.expression  = expression;
3166         typeof_type->typeoft.typeof_type = type;
3167
3168         return typeof_type;
3169 end_error:
3170         return NULL;
3171 }
3172
3173 typedef enum specifiers_t {
3174         SPECIFIER_SIGNED    = 1 << 0,
3175         SPECIFIER_UNSIGNED  = 1 << 1,
3176         SPECIFIER_LONG      = 1 << 2,
3177         SPECIFIER_INT       = 1 << 3,
3178         SPECIFIER_DOUBLE    = 1 << 4,
3179         SPECIFIER_CHAR      = 1 << 5,
3180         SPECIFIER_SHORT     = 1 << 6,
3181         SPECIFIER_LONG_LONG = 1 << 7,
3182         SPECIFIER_FLOAT     = 1 << 8,
3183         SPECIFIER_BOOL      = 1 << 9,
3184         SPECIFIER_VOID      = 1 << 10,
3185         SPECIFIER_INT8      = 1 << 11,
3186         SPECIFIER_INT16     = 1 << 12,
3187         SPECIFIER_INT32     = 1 << 13,
3188         SPECIFIER_INT64     = 1 << 14,
3189         SPECIFIER_INT128    = 1 << 15,
3190         SPECIFIER_COMPLEX   = 1 << 16,
3191         SPECIFIER_IMAGINARY = 1 << 17,
3192 } specifiers_t;
3193
3194 static type_t *create_builtin_type(symbol_t *const symbol,
3195                                    type_t *const real_type)
3196 {
3197         type_t *type            = allocate_type_zero(TYPE_BUILTIN);
3198         type->builtin.symbol    = symbol;
3199         type->builtin.real_type = real_type;
3200
3201         type_t *result = typehash_insert(type);
3202         if (type != result) {
3203                 free_type(type);
3204         }
3205
3206         return result;
3207 }
3208
3209 static type_t *get_typedef_type(symbol_t *symbol)
3210 {
3211         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
3212         if (declaration == NULL ||
3213            declaration->storage_class != STORAGE_CLASS_TYPEDEF)
3214                 return NULL;
3215
3216         type_t *type               = allocate_type_zero(TYPE_TYPEDEF);
3217         type->typedeft.declaration = declaration;
3218
3219         return type;
3220 }
3221
3222 /**
3223  * check for the allowed MS alignment values.
3224  */
3225 static bool check_alignment_value(long long intvalue)
3226 {
3227         if (intvalue < 1 || intvalue > 8192) {
3228                 errorf(HERE, "illegal alignment value");
3229                 return false;
3230         }
3231         unsigned v = (unsigned)intvalue;
3232         for (unsigned i = 1; i <= 8192; i += i) {
3233                 if (i == v)
3234                         return true;
3235         }
3236         errorf(HERE, "alignment must be power of two");
3237         return false;
3238 }
3239
3240 #define DET_MOD(name, tag) do { \
3241         if (*modifiers & tag && warning.other) warningf(HERE, #name " used more than once"); \
3242         *modifiers |= tag; \
3243 } while (0)
3244
3245 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
3246 {
3247         decl_modifiers_t *modifiers = &specifiers->modifiers;
3248
3249         while (true) {
3250                 if (token.type == T_restrict) {
3251                         next_token();
3252                         DET_MOD(restrict, DM_RESTRICT);
3253                         goto end_loop;
3254                 } else if (token.type != T_IDENTIFIER)
3255                         break;
3256                 symbol_t *symbol = token.v.symbol;
3257                 if (symbol == sym_align) {
3258                         next_token();
3259                         expect('(');
3260                         if (token.type != T_INTEGER)
3261                                 goto end_error;
3262                         if (check_alignment_value(token.v.intvalue)) {
3263                                 if (specifiers->alignment != 0 && warning.other)
3264                                         warningf(HERE, "align used more than once");
3265                                 specifiers->alignment = (unsigned char)token.v.intvalue;
3266                         }
3267                         next_token();
3268                         expect(')');
3269                 } else if (symbol == sym_allocate) {
3270                         next_token();
3271                         expect('(');
3272                         if (token.type != T_IDENTIFIER)
3273                                 goto end_error;
3274                         (void)token.v.symbol;
3275                         expect(')');
3276                 } else if (symbol == sym_dllimport) {
3277                         next_token();
3278                         DET_MOD(dllimport, DM_DLLIMPORT);
3279                 } else if (symbol == sym_dllexport) {
3280                         next_token();
3281                         DET_MOD(dllexport, DM_DLLEXPORT);
3282                 } else if (symbol == sym_thread) {
3283                         next_token();
3284                         DET_MOD(thread, DM_THREAD);
3285                 } else if (symbol == sym_naked) {
3286                         next_token();
3287                         DET_MOD(naked, DM_NAKED);
3288                 } else if (symbol == sym_noinline) {
3289                         next_token();
3290                         DET_MOD(noinline, DM_NOINLINE);
3291                 } else if (symbol == sym_noreturn) {
3292                         next_token();
3293                         DET_MOD(noreturn, DM_NORETURN);
3294                 } else if (symbol == sym_nothrow) {
3295                         next_token();
3296                         DET_MOD(nothrow, DM_NOTHROW);
3297                 } else if (symbol == sym_novtable) {
3298                         next_token();
3299                         DET_MOD(novtable, DM_NOVTABLE);
3300                 } else if (symbol == sym_property) {
3301                         next_token();
3302                         expect('(');
3303                         for (;;) {
3304                                 bool is_get = false;
3305                                 if (token.type != T_IDENTIFIER)
3306                                         goto end_error;
3307                                 if (token.v.symbol == sym_get) {
3308                                         is_get = true;
3309                                 } else if (token.v.symbol == sym_put) {
3310                                 } else {
3311                                         errorf(HERE, "Bad property name '%Y'", token.v.symbol);
3312                                         goto end_error;
3313                                 }
3314                                 next_token();
3315                                 expect('=');
3316                                 if (token.type != T_IDENTIFIER)
3317                                         goto end_error;
3318                                 if (is_get) {
3319                                         if (specifiers->get_property_sym != NULL) {
3320                                                 errorf(HERE, "get property name already specified");
3321                                         } else {
3322                                                 specifiers->get_property_sym = token.v.symbol;
3323                                         }
3324                                 } else {
3325                                         if (specifiers->put_property_sym != NULL) {
3326                                                 errorf(HERE, "put property name already specified");
3327                                         } else {
3328                                                 specifiers->put_property_sym = token.v.symbol;
3329                                         }
3330                                 }
3331                                 next_token();
3332                                 if (token.type == ',') {
3333                                         next_token();
3334                                         continue;
3335                                 }
3336                                 break;
3337                         }
3338                         expect(')');
3339                 } else if (symbol == sym_selectany) {
3340                         next_token();
3341                         DET_MOD(selectany, DM_SELECTANY);
3342                 } else if (symbol == sym_uuid) {
3343                         next_token();
3344                         expect('(');
3345                         if (token.type != T_STRING_LITERAL)
3346                                 goto end_error;
3347                         next_token();
3348                         expect(')');
3349                 } else if (symbol == sym_deprecated) {
3350                         next_token();
3351                         if (specifiers->deprecated != 0 && warning.other)
3352                                 warningf(HERE, "deprecated used more than once");
3353                         specifiers->deprecated = 1;
3354                         if (token.type == '(') {
3355                                 next_token();
3356                                 if (token.type == T_STRING_LITERAL) {
3357                                         specifiers->deprecated_string = token.v.string.begin;
3358                                         next_token();
3359                                 } else {
3360                                         errorf(HERE, "string literal expected");
3361                                 }
3362                                 expect(')');
3363                         }
3364                 } else if (symbol == sym_noalias) {
3365                         next_token();
3366                         DET_MOD(noalias, DM_NOALIAS);
3367                 } else {
3368                         if (warning.other)
3369                                 warningf(HERE, "Unknown modifier %Y ignored", token.v.symbol);
3370                         next_token();
3371                         if (token.type == '(')
3372                                 skip_until(')');
3373                 }
3374 end_loop:
3375                 if (token.type == ',')
3376                         next_token();
3377         }
3378 end_error:
3379         return;
3380 }
3381
3382 static declaration_t *create_error_declaration(symbol_t *symbol, storage_class_tag_t storage_class)
3383 {
3384         declaration_t *const decl    = allocate_declaration_zero();
3385         decl->source_position        = *HERE;
3386         decl->declared_storage_class = storage_class;
3387         decl->storage_class          =
3388                 storage_class != STORAGE_CLASS_NONE || scope == file_scope ?
3389                         storage_class : STORAGE_CLASS_AUTO;
3390         decl->symbol                 = symbol;
3391         decl->implicit               = true;
3392         record_declaration(decl, false);
3393         return decl;
3394 }
3395
3396 /**
3397  * Finish the construction of a struct type by calculating
3398  * its size, offsets, alignment.
3399  */
3400 static void finish_struct_type(compound_type_t *type) {
3401         if (type->declaration == NULL)
3402                 return;
3403         declaration_t *struct_decl = type->declaration;
3404         if (! struct_decl->init.complete)
3405                 return;
3406
3407         il_size_t      size           = 0;
3408         il_size_t      offset;
3409         il_alignment_t alignment      = 1;
3410         bool           need_pad       = false;
3411
3412         declaration_t *entry = struct_decl->scope.declarations;
3413         for (; entry != NULL; entry = entry->next) {
3414                 if (entry->namespc != NAMESPACE_NORMAL)
3415                         continue;
3416
3417                 type_t *m_type = skip_typeref(entry->type);
3418                 if (! is_type_valid(m_type)) {
3419                         /* simply ignore errors here */
3420                         continue;
3421                 }
3422                 il_alignment_t m_alignment = m_type->base.alignment;
3423                 if (m_alignment > alignment)
3424                         alignment = m_alignment;
3425
3426                 offset = (size + m_alignment - 1) & -m_alignment;
3427
3428                 if (offset > size)
3429                         need_pad = true;
3430                 entry->offset = offset;
3431                 size = offset + m_type->base.size;
3432         }
3433         if (type->base.alignment != 0) {
3434                 alignment = type->base.alignment;
3435         }
3436
3437         offset = (size + alignment - 1) & -alignment;
3438         if (offset > size)
3439                 need_pad = true;
3440
3441         if (warning.padded && need_pad) {
3442                 warningf(&struct_decl->source_position,
3443                         "'%#T' needs padding", type, struct_decl->symbol);
3444         }
3445         if (warning.packed && !need_pad) {
3446                 warningf(&struct_decl->source_position,
3447                         "superfluous packed attribute on '%#T'",
3448                         type, struct_decl->symbol);
3449         }
3450
3451         type->base.size      = offset;
3452         type->base.alignment = alignment;
3453 }
3454
3455 /**
3456  * Finish the construction of an union type by calculating
3457  * its size and alignment.
3458  */
3459 static void finish_union_type(compound_type_t *type) {
3460         if (type->declaration == NULL)
3461                 return;
3462         declaration_t *union_decl = type->declaration;
3463         if (! union_decl->init.complete)
3464                 return;
3465
3466         il_size_t      size      = 0;
3467         il_alignment_t alignment = 1;
3468
3469         declaration_t *entry = union_decl->scope.declarations;
3470         for (; entry != NULL; entry = entry->next) {
3471                 if (entry->namespc != NAMESPACE_NORMAL)
3472                         continue;
3473
3474                 type_t *m_type = skip_typeref(entry->type);
3475                 if (! is_type_valid(m_type))
3476                         continue;
3477
3478                 entry->offset = 0;
3479                 if (m_type->base.size > size)
3480                         size = m_type->base.size;
3481                 if (m_type->base.alignment > alignment)
3482                         alignment = m_type->base.alignment;
3483         }
3484         if (type->base.alignment != 0) {
3485                 alignment = type->base.alignment;
3486         }
3487         size = (size + alignment - 1) & -alignment;
3488         type->base.size      = size;
3489         type->base.alignment = alignment;
3490 }
3491
3492 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
3493 {
3494         type_t            *type              = NULL;
3495         type_qualifiers_t  qualifiers        = TYPE_QUALIFIER_NONE;
3496         type_modifiers_t   modifiers         = TYPE_MODIFIER_NONE;
3497         unsigned           type_specifiers   = 0;
3498         bool               newtype           = false;
3499         bool               saw_error         = false;
3500         bool               old_gcc_extension = in_gcc_extension;
3501
3502         specifiers->source_position = token.source_position;
3503
3504         while (true) {
3505                 specifiers->modifiers
3506                         |= parse_attributes(&specifiers->gnu_attributes);
3507                 if (specifiers->modifiers & DM_TRANSPARENT_UNION)
3508                         modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3509
3510                 switch (token.type) {
3511
3512                 /* storage class */
3513 #define MATCH_STORAGE_CLASS(token, class)                                  \
3514                 case token:                                                        \
3515                         if (specifiers->declared_storage_class != STORAGE_CLASS_NONE) { \
3516                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3517                         }                                                              \
3518                         specifiers->declared_storage_class = class;                    \
3519                         next_token();                                                  \
3520                         break;
3521
3522                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3523                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3524                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3525                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3526                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3527
3528                 case T__declspec:
3529                         next_token();
3530                         expect('(');
3531                         add_anchor_token(')');
3532                         parse_microsoft_extended_decl_modifier(specifiers);
3533                         rem_anchor_token(')');
3534                         expect(')');
3535                         break;
3536
3537                 case T___thread:
3538                         switch (specifiers->declared_storage_class) {
3539                         case STORAGE_CLASS_NONE:
3540                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD;
3541                                 break;
3542
3543                         case STORAGE_CLASS_EXTERN:
3544                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_EXTERN;
3545                                 break;
3546
3547                         case STORAGE_CLASS_STATIC:
3548                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_STATIC;
3549                                 break;
3550
3551                         default:
3552                                 errorf(HERE, "multiple storage classes in declaration specifiers");
3553                                 break;
3554                         }
3555                         next_token();
3556                         break;
3557
3558                 /* type qualifiers */
3559 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3560                 case token:                                                     \
3561                         qualifiers |= qualifier;                                    \
3562                         next_token();                                               \
3563                         break
3564
3565                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3566                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3567                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3568                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3569                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3570                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3571                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3572                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3573
3574                 case T___extension__:
3575                         next_token();
3576                         in_gcc_extension = true;
3577                         break;
3578
3579                 /* type specifiers */
3580 #define MATCH_SPECIFIER(token, specifier, name)                         \
3581                 case token:                                                     \
3582                         next_token();                                               \
3583                         if (type_specifiers & specifier) {                           \
3584                                 errorf(HERE, "multiple " name " type specifiers given"); \
3585                         } else {                                                    \
3586                                 type_specifiers |= specifier;                           \
3587                         }                                                           \
3588                         break
3589
3590                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3591                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3592                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3593                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3594                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3595                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3596                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3597                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3598                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3599                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3600                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3601                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3602                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3603                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3604                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3605                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3606
3607                 case T__forceinline:
3608                         /* only in microsoft mode */
3609                         specifiers->modifiers |= DM_FORCEINLINE;
3610                         /* FALLTHROUGH */
3611
3612                 case T_inline:
3613                         next_token();
3614                         specifiers->is_inline = true;
3615                         break;
3616
3617                 case T_long:
3618                         next_token();
3619                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3620                                 errorf(HERE, "multiple type specifiers given");
3621                         } else if (type_specifiers & SPECIFIER_LONG) {
3622                                 type_specifiers |= SPECIFIER_LONG_LONG;
3623                         } else {
3624                                 type_specifiers |= SPECIFIER_LONG;
3625                         }
3626                         break;
3627
3628                 case T_struct: {
3629                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT);
3630
3631                         type->compound.declaration = parse_compound_type_specifier(true);
3632                         finish_struct_type(&type->compound);
3633                         break;
3634                 }
3635                 case T_union: {
3636                         type = allocate_type_zero(TYPE_COMPOUND_UNION);
3637                         type->compound.declaration = parse_compound_type_specifier(false);
3638                         if (type->compound.declaration->modifiers & DM_TRANSPARENT_UNION)
3639                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3640                         finish_union_type(&type->compound);
3641                         break;
3642                 }
3643                 case T_enum:
3644                         type = parse_enum_specifier();
3645                         break;
3646                 case T___typeof__:
3647                         type = parse_typeof();
3648                         break;
3649                 case T___builtin_va_list:
3650                         type = duplicate_type(type_valist);
3651                         next_token();
3652                         break;
3653
3654                 case T_IDENTIFIER: {
3655                         /* only parse identifier if we haven't found a type yet */
3656                         if (type != NULL || type_specifiers != 0) {
3657                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
3658                                  * declaration, so it doesn't generate errors about expecting '(' or
3659                                  * '{' later on. */
3660                                 switch (look_ahead(1)->type) {
3661                                         STORAGE_CLASSES
3662                                         TYPE_SPECIFIERS
3663                                         case T_const:
3664                                         case T_restrict:
3665                                         case T_volatile:
3666                                         case T_inline:
3667                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
3668                                         case T_IDENTIFIER:
3669                                         case '*':
3670                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
3671                                                 next_token();
3672                                                 continue;
3673
3674                                         default:
3675                                                 goto finish_specifiers;
3676                                 }
3677                         }
3678
3679                         type_t *const typedef_type = get_typedef_type(token.v.symbol);
3680                         if (typedef_type == NULL) {
3681                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3682                                  * declaration, so it doesn't generate 'implicit int' followed by more
3683                                  * errors later on. */
3684                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3685                                 switch (la1_type) {
3686                                         DECLARATION_START
3687                                         case T_IDENTIFIER:
3688                                         case '*': {
3689                                                 errorf(HERE, "%K does not name a type", &token);
3690
3691                                                 declaration_t *const decl =
3692                                                         create_error_declaration(token.v.symbol, STORAGE_CLASS_TYPEDEF);
3693
3694                                                 type = allocate_type_zero(TYPE_TYPEDEF);
3695                                                 type->typedeft.declaration = decl;
3696
3697                                                 next_token();
3698                                                 saw_error = true;
3699                                                 if (la1_type == '*')
3700                                                         goto finish_specifiers;
3701                                                 continue;
3702                                         }
3703
3704                                         default:
3705                                                 goto finish_specifiers;
3706                                 }
3707                         }
3708
3709                         next_token();
3710                         type = typedef_type;
3711                         break;
3712                 }
3713
3714                 /* function specifier */
3715                 default:
3716                         goto finish_specifiers;
3717                 }
3718         }
3719
3720 finish_specifiers:
3721         in_gcc_extension = old_gcc_extension;
3722
3723         if (type == NULL || (saw_error && type_specifiers != 0)) {
3724                 atomic_type_kind_t atomic_type;
3725
3726                 /* match valid basic types */
3727                 switch(type_specifiers) {
3728                 case SPECIFIER_VOID:
3729                         atomic_type = ATOMIC_TYPE_VOID;
3730                         break;
3731                 case SPECIFIER_CHAR:
3732                         atomic_type = ATOMIC_TYPE_CHAR;
3733                         break;
3734                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3735                         atomic_type = ATOMIC_TYPE_SCHAR;
3736                         break;
3737                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3738                         atomic_type = ATOMIC_TYPE_UCHAR;
3739                         break;
3740                 case SPECIFIER_SHORT:
3741                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3742                 case SPECIFIER_SHORT | SPECIFIER_INT:
3743                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3744                         atomic_type = ATOMIC_TYPE_SHORT;
3745                         break;
3746                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3747                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3748                         atomic_type = ATOMIC_TYPE_USHORT;
3749                         break;
3750                 case SPECIFIER_INT:
3751                 case SPECIFIER_SIGNED:
3752                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3753                         atomic_type = ATOMIC_TYPE_INT;
3754                         break;
3755                 case SPECIFIER_UNSIGNED:
3756                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3757                         atomic_type = ATOMIC_TYPE_UINT;
3758                         break;
3759                 case SPECIFIER_LONG:
3760                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3761                 case SPECIFIER_LONG | SPECIFIER_INT:
3762                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3763                         atomic_type = ATOMIC_TYPE_LONG;
3764                         break;
3765                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3766                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3767                         atomic_type = ATOMIC_TYPE_ULONG;
3768                         break;
3769
3770                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3771                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3772                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3773                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3774                         | SPECIFIER_INT:
3775                         atomic_type = ATOMIC_TYPE_LONGLONG;
3776                         goto warn_about_long_long;
3777
3778                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3779                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3780                         | SPECIFIER_INT:
3781                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3782 warn_about_long_long:
3783                         if (warning.long_long) {
3784                                 warningf(&specifiers->source_position,
3785                                          "ISO C90 does not support 'long long'");
3786                         }
3787                         break;
3788
3789                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3790                         atomic_type = unsigned_int8_type_kind;
3791                         break;
3792
3793                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3794                         atomic_type = unsigned_int16_type_kind;
3795                         break;
3796
3797                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3798                         atomic_type = unsigned_int32_type_kind;
3799                         break;
3800
3801                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3802                         atomic_type = unsigned_int64_type_kind;
3803                         break;
3804
3805                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3806                         atomic_type = unsigned_int128_type_kind;
3807                         break;
3808
3809                 case SPECIFIER_INT8:
3810                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3811                         atomic_type = int8_type_kind;
3812                         break;
3813
3814                 case SPECIFIER_INT16:
3815                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3816                         atomic_type = int16_type_kind;
3817                         break;
3818
3819                 case SPECIFIER_INT32:
3820                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3821                         atomic_type = int32_type_kind;
3822                         break;
3823
3824                 case SPECIFIER_INT64:
3825                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3826                         atomic_type = int64_type_kind;
3827                         break;
3828
3829                 case SPECIFIER_INT128:
3830                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3831                         atomic_type = int128_type_kind;
3832                         break;
3833
3834                 case SPECIFIER_FLOAT:
3835                         atomic_type = ATOMIC_TYPE_FLOAT;
3836                         break;
3837                 case SPECIFIER_DOUBLE:
3838                         atomic_type = ATOMIC_TYPE_DOUBLE;
3839                         break;
3840                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3841                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3842                         break;
3843                 case SPECIFIER_BOOL:
3844                         atomic_type = ATOMIC_TYPE_BOOL;
3845                         break;
3846                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3847                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3848                         atomic_type = ATOMIC_TYPE_FLOAT;
3849                         break;
3850                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3851                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3852                         atomic_type = ATOMIC_TYPE_DOUBLE;
3853                         break;
3854                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3855                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3856                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3857                         break;
3858                 default:
3859                         /* invalid specifier combination, give an error message */
3860                         if (type_specifiers == 0) {
3861                                 if (saw_error)
3862                                         goto end_error;
3863
3864                                 if (!strict_mode) {
3865                                         if (warning.implicit_int) {
3866                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
3867                                         }
3868                                         atomic_type = ATOMIC_TYPE_INT;
3869                                         break;
3870                                 } else {
3871                                         errorf(HERE, "no type specifiers given in declaration");
3872                                 }
3873                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
3874                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
3875                                 errorf(HERE, "signed and unsigned specifiers given");
3876                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
3877                                 errorf(HERE, "only integer types can be signed or unsigned");
3878                         } else {
3879                                 errorf(HERE, "multiple datatypes in declaration");
3880                         }
3881                         goto end_error;
3882                 }
3883
3884                 if (type_specifiers & SPECIFIER_COMPLEX) {
3885                         type                = allocate_type_zero(TYPE_COMPLEX);
3886                         type->complex.akind = atomic_type;
3887                 } else if (type_specifiers & SPECIFIER_IMAGINARY) {
3888                         type                  = allocate_type_zero(TYPE_IMAGINARY);
3889                         type->imaginary.akind = atomic_type;
3890                 } else {
3891                         type               = allocate_type_zero(TYPE_ATOMIC);
3892                         type->atomic.akind = atomic_type;
3893                 }
3894                 newtype = true;
3895         } else if (type_specifiers != 0) {
3896                 errorf(HERE, "multiple datatypes in declaration");
3897         }
3898
3899         /* FIXME: check type qualifiers here */
3900
3901         type->base.qualifiers = qualifiers;
3902         type->base.modifiers  = modifiers;
3903
3904         type_t *result = typehash_insert(type);
3905         if (newtype && result != type) {
3906                 free_type(type);
3907         }
3908
3909         specifiers->type = result;
3910         return;
3911
3912 end_error:
3913         specifiers->type = type_error_type;
3914         return;
3915 }
3916
3917 static type_qualifiers_t parse_type_qualifiers(void)
3918 {
3919         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
3920
3921         while (true) {
3922                 switch(token.type) {
3923                 /* type qualifiers */
3924                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3925                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3926                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3927                 /* microsoft extended type modifiers */
3928                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3929                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3930                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3931                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3932                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3933
3934                 default:
3935                         return qualifiers;
3936                 }
3937         }
3938 }
3939
3940 /**
3941  * Parses an K&R identifier list and return a list of declarations.
3942  *
3943  * @param last  points to the last declaration in the list
3944  * @return the list of declarations
3945  */
3946 static declaration_t *parse_identifier_list(declaration_t **last)
3947 {
3948         declaration_t *declarations     = NULL;
3949         declaration_t *last_declaration = NULL;
3950         do {
3951                 declaration_t *const declaration = allocate_declaration_zero();
3952                 declaration->type            = NULL; /* a K&R parameter list has no types, yet */
3953                 declaration->source_position = token.source_position;
3954                 declaration->symbol          = token.v.symbol;
3955                 next_token();
3956
3957                 if (last_declaration != NULL) {
3958                         last_declaration->next = declaration;
3959                 } else {
3960                         declarations = declaration;
3961                 }
3962                 last_declaration = declaration;
3963
3964                 if (token.type != ',') {
3965                         break;
3966                 }
3967                 next_token();
3968         } while (token.type == T_IDENTIFIER);
3969
3970         *last = last_declaration;
3971         return declarations;
3972 }
3973
3974 static type_t *automatic_type_conversion(type_t *orig_type);
3975
3976 static void semantic_parameter(declaration_t *declaration)
3977 {
3978         /* TODO: improve error messages */
3979         source_position_t const* const pos = &declaration->source_position;
3980
3981         switch (declaration->declared_storage_class) {
3982                 case STORAGE_CLASS_TYPEDEF:
3983                         errorf(pos, "typedef not allowed in parameter list");
3984                         break;
3985
3986                 /* Allowed storage classes */
3987                 case STORAGE_CLASS_NONE:
3988                 case STORAGE_CLASS_REGISTER:
3989                         break;
3990
3991                 default:
3992                         errorf(pos, "parameter may only have none or register storage class");
3993                         break;
3994         }
3995
3996         type_t *const orig_type = declaration->type;
3997         /* §6.7.5.3(7): Array as last part of a parameter type is just syntactic
3998          * sugar.  Turn it into a pointer.
3999          * §6.7.5.3(8): A declaration of a parameter as ``function returning type''
4000          * shall be adjusted to ``pointer to function returning type'', as in 6.3.2.1.
4001          */
4002         type_t *const type = automatic_type_conversion(orig_type);
4003         declaration->type = type;
4004
4005         if (is_type_incomplete(skip_typeref(type))) {
4006                 errorf(pos, "parameter '%#T' is of incomplete type",
4007                        orig_type, declaration->symbol);
4008         }
4009 }
4010
4011 static declaration_t *parse_parameter(void)
4012 {
4013         declaration_specifiers_t specifiers;
4014         memset(&specifiers, 0, sizeof(specifiers));
4015
4016         parse_declaration_specifiers(&specifiers);
4017
4018         declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/true);
4019
4020         return declaration;
4021 }
4022
4023 /**
4024  * Parses a function type parameter list and return a list of declarations.
4025  *
4026  * @param last  point to the last element of the list
4027  * @return the parameter list
4028  */
4029 static declaration_t *parse_parameters(function_type_t *type, declaration_t **last)
4030 {
4031         declaration_t *declarations = NULL;
4032
4033         eat('(');
4034         add_anchor_token(')');
4035         int saved_comma_state = save_and_reset_anchor_state(',');
4036
4037         if (token.type == T_IDENTIFIER &&
4038             !is_typedef_symbol(token.v.symbol)) {
4039                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
4040                 if (la1_type == ',' || la1_type == ')') {
4041                         type->kr_style_parameters = true;
4042                         declarations = parse_identifier_list(last);
4043                         goto parameters_finished;
4044                 }
4045         }
4046
4047         if (token.type == ')') {
4048                 type->unspecified_parameters = 1;
4049                 goto parameters_finished;
4050         }
4051
4052         declaration_t        *declaration;
4053         declaration_t        *last_declaration = NULL;
4054         function_parameter_t *parameter;
4055         function_parameter_t *last_parameter = NULL;
4056
4057         while (true) {
4058                 switch(token.type) {
4059                 case T_DOTDOTDOT:
4060                         next_token();
4061                         type->variadic = 1;
4062                         goto parameters_finished;
4063
4064                 case T_IDENTIFIER:
4065                 case T___extension__:
4066                 DECLARATION_START
4067                         declaration = parse_parameter();
4068
4069                         /* func(void) is not a parameter */
4070                         if (last_parameter == NULL
4071                                         && token.type == ')'
4072                                         && declaration->symbol == NULL
4073                                         && skip_typeref(declaration->type) == type_void) {
4074                                 goto parameters_finished;
4075                         }
4076                         semantic_parameter(declaration);
4077
4078                         parameter       = obstack_alloc(type_obst, sizeof(parameter[0]));
4079                         memset(parameter, 0, sizeof(parameter[0]));
4080                         parameter->type = declaration->type;
4081
4082                         if (last_parameter != NULL) {
4083                                 last_declaration->next = declaration;
4084                                 last_parameter->next   = parameter;
4085                         } else {
4086                                 type->parameters = parameter;
4087                                 declarations     = declaration;
4088                         }
4089                         last_parameter   = parameter;
4090                         last_declaration = declaration;
4091                         break;
4092
4093                 default:
4094                         goto parameters_finished;
4095                 }
4096                 if (token.type != ',') {
4097                         goto parameters_finished;
4098                 }
4099                 next_token();
4100         }
4101
4102
4103 parameters_finished:
4104         rem_anchor_token(')');
4105         expect(')');
4106
4107         restore_anchor_state(',', saved_comma_state);
4108         *last = last_declaration;
4109         return declarations;
4110
4111 end_error:
4112         restore_anchor_state(',', saved_comma_state);
4113         *last = NULL;
4114         return NULL;
4115 }
4116
4117 typedef enum construct_type_kind_t {
4118         CONSTRUCT_INVALID,
4119         CONSTRUCT_POINTER,
4120         CONSTRUCT_FUNCTION,
4121         CONSTRUCT_ARRAY
4122 } construct_type_kind_t;
4123
4124 typedef struct construct_type_t construct_type_t;
4125 struct construct_type_t {
4126         construct_type_kind_t  kind;
4127         construct_type_t      *next;
4128 };
4129
4130 typedef struct parsed_pointer_t parsed_pointer_t;
4131 struct parsed_pointer_t {
4132         construct_type_t  construct_type;
4133         type_qualifiers_t type_qualifiers;
4134 };
4135
4136 typedef struct construct_function_type_t construct_function_type_t;
4137 struct construct_function_type_t {
4138         construct_type_t  construct_type;
4139         type_t           *function_type;
4140 };
4141
4142 typedef struct parsed_array_t parsed_array_t;
4143 struct parsed_array_t {
4144         construct_type_t  construct_type;
4145         type_qualifiers_t type_qualifiers;
4146         bool              is_static;
4147         bool              is_variable;
4148         expression_t     *size;
4149 };
4150
4151 typedef struct construct_base_type_t construct_base_type_t;
4152 struct construct_base_type_t {
4153         construct_type_t  construct_type;
4154         type_t           *type;
4155 };
4156
4157 static construct_type_t *parse_pointer_declarator(void)
4158 {
4159         eat('*');
4160
4161         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
4162         memset(pointer, 0, sizeof(pointer[0]));
4163         pointer->construct_type.kind = CONSTRUCT_POINTER;
4164         pointer->type_qualifiers     = parse_type_qualifiers();
4165
4166         return (construct_type_t*) pointer;
4167 }
4168
4169 static construct_type_t *parse_array_declarator(void)
4170 {
4171         eat('[');
4172         add_anchor_token(']');
4173
4174         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
4175         memset(array, 0, sizeof(array[0]));
4176         array->construct_type.kind = CONSTRUCT_ARRAY;
4177
4178         if (token.type == T_static) {
4179                 array->is_static = true;
4180                 next_token();
4181         }
4182
4183         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
4184         if (type_qualifiers != 0) {
4185                 if (token.type == T_static) {
4186                         array->is_static = true;
4187                         next_token();
4188                 }
4189         }
4190         array->type_qualifiers = type_qualifiers;
4191
4192         if (token.type == '*' && look_ahead(1)->type == ']') {
4193                 array->is_variable = true;
4194                 next_token();
4195         } else if (token.type != ']') {
4196                 array->size = parse_assignment_expression();
4197         }
4198
4199         rem_anchor_token(']');
4200         expect(']');
4201
4202 end_error:
4203         return (construct_type_t*) array;
4204 }
4205
4206 static construct_type_t *parse_function_declarator(declaration_t *declaration)
4207 {
4208         type_t *type;
4209         if (declaration != NULL) {
4210                 type = allocate_type_zero(TYPE_FUNCTION);
4211
4212                 unsigned mask = declaration->modifiers & (DM_CDECL|DM_STDCALL|DM_FASTCALL|DM_THISCALL);
4213
4214                 if (mask & (mask-1)) {
4215                         const char *first = NULL, *second = NULL;
4216
4217                         /* more than one calling convention set */
4218                         if (declaration->modifiers & DM_CDECL) {
4219                                 if (first == NULL)       first = "cdecl";
4220                                 else if (second == NULL) second = "cdecl";
4221                         }
4222                         if (declaration->modifiers & DM_STDCALL) {
4223                                 if (first == NULL)       first = "stdcall";
4224                                 else if (second == NULL) second = "stdcall";
4225                         }
4226                         if (declaration->modifiers & DM_FASTCALL) {
4227                                 if (first == NULL)       first = "fastcall";
4228                                 else if (second == NULL) second = "fastcall";
4229                         }
4230                         if (declaration->modifiers & DM_THISCALL) {
4231                                 if (first == NULL)       first = "thiscall";
4232                                 else if (second == NULL) second = "thiscall";
4233                         }
4234                         errorf(&declaration->source_position, "%s and %s attributes are not compatible", first, second);
4235                 }
4236
4237                 if (declaration->modifiers & DM_CDECL)
4238                         type->function.calling_convention = CC_CDECL;
4239                 else if (declaration->modifiers & DM_STDCALL)
4240                         type->function.calling_convention = CC_STDCALL;
4241                 else if (declaration->modifiers & DM_FASTCALL)
4242                         type->function.calling_convention = CC_FASTCALL;
4243                 else if (declaration->modifiers & DM_THISCALL)
4244                         type->function.calling_convention = CC_THISCALL;
4245         } else {
4246                 type = allocate_type_zero(TYPE_FUNCTION);
4247         }
4248
4249         declaration_t *last;
4250         declaration_t *parameters = parse_parameters(&type->function, &last);
4251         if (declaration != NULL) {
4252                 declaration->scope.declarations     = parameters;
4253                 declaration->scope.last_declaration = last;
4254         }
4255
4256         construct_function_type_t *construct_function_type =
4257                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
4258         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
4259         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
4260         construct_function_type->function_type       = type;
4261
4262         return &construct_function_type->construct_type;
4263 }
4264
4265 static void fix_declaration_type(declaration_t *declaration)
4266 {
4267         decl_modifiers_t declaration_modifiers = declaration->modifiers;
4268         type_modifiers_t type_modifiers        = declaration->type->base.modifiers;
4269
4270         if (declaration_modifiers & DM_TRANSPARENT_UNION)
4271                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
4272
4273         if (declaration->type->base.modifiers == type_modifiers)
4274                 return;
4275
4276         type_t *copy = duplicate_type(declaration->type);
4277         copy->base.modifiers = type_modifiers;
4278
4279         type_t *result = typehash_insert(copy);
4280         if (result != copy) {
4281                 obstack_free(type_obst, copy);
4282         }
4283
4284         declaration->type = result;
4285 }
4286
4287 static construct_type_t *parse_inner_declarator(declaration_t *declaration,
4288                 bool may_be_abstract)
4289 {
4290         /* construct a single linked list of construct_type_t's which describe
4291          * how to construct the final declarator type */
4292         construct_type_t *first = NULL;
4293         construct_type_t *last  = NULL;
4294         gnu_attribute_t  *attributes = NULL;
4295
4296         decl_modifiers_t modifiers = parse_attributes(&attributes);
4297
4298         /* pointers */
4299         while (token.type == '*') {
4300                 construct_type_t *type = parse_pointer_declarator();
4301
4302                 if (last == NULL) {
4303                         first = type;
4304                         last  = type;
4305                 } else {
4306                         last->next = type;
4307                         last       = type;
4308                 }
4309
4310                 /* TODO: find out if this is correct */
4311                 modifiers |= parse_attributes(&attributes);
4312         }
4313
4314         if (declaration != NULL)
4315                 declaration->modifiers |= modifiers;
4316
4317         construct_type_t *inner_types = NULL;
4318
4319         switch(token.type) {
4320         case T_IDENTIFIER:
4321                 if (declaration == NULL) {
4322                         errorf(HERE, "no identifier expected in typename");
4323                 } else {
4324                         declaration->symbol          = token.v.symbol;
4325                         declaration->source_position = token.source_position;
4326                 }
4327                 next_token();
4328                 break;
4329         case '(':
4330                 next_token();
4331                 add_anchor_token(')');
4332                 inner_types = parse_inner_declarator(declaration, may_be_abstract);
4333                 if (inner_types != NULL) {
4334                         /* All later declarators only modify the return type, not declaration */
4335                         declaration = NULL;
4336                 }
4337                 rem_anchor_token(')');
4338                 expect(')');
4339                 break;
4340         default:
4341                 if (may_be_abstract)
4342                         break;
4343                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
4344                 eat_until_anchor();
4345                 return NULL;
4346         }
4347
4348         construct_type_t *p = last;
4349
4350         while(true) {
4351                 construct_type_t *type;
4352                 switch(token.type) {
4353                 case '(':
4354                         type = parse_function_declarator(declaration);
4355                         break;
4356                 case '[':
4357                         type = parse_array_declarator();
4358                         break;
4359                 default:
4360                         goto declarator_finished;
4361                 }
4362
4363                 /* insert in the middle of the list (behind p) */
4364                 if (p != NULL) {
4365                         type->next = p->next;
4366                         p->next    = type;
4367                 } else {
4368                         type->next = first;
4369                         first      = type;
4370                 }
4371                 if (last == p) {
4372                         last = type;
4373                 }
4374         }
4375
4376 declarator_finished:
4377         /* append inner_types at the end of the list, we don't to set last anymore
4378          * as it's not needed anymore */
4379         if (last == NULL) {
4380                 assert(first == NULL);
4381                 first = inner_types;
4382         } else {
4383                 last->next = inner_types;
4384         }
4385
4386         return first;
4387 end_error:
4388         return NULL;
4389 }
4390
4391 static void parse_declaration_attributes(declaration_t *declaration)
4392 {
4393         gnu_attribute_t  *attributes = NULL;
4394         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
4395
4396         if (declaration == NULL)
4397                 return;
4398
4399         declaration->modifiers |= modifiers;
4400         /* check if we have these stupid mode attributes... */
4401         type_t *old_type = declaration->type;
4402         if (old_type == NULL)
4403                 return;
4404
4405         gnu_attribute_t *attribute = attributes;
4406         for ( ; attribute != NULL; attribute = attribute->next) {
4407                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
4408                         continue;
4409
4410                 atomic_type_kind_t  akind = attribute->u.akind;
4411                 if (!is_type_signed(old_type)) {
4412                         switch(akind) {
4413                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
4414                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
4415                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
4416                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
4417                         default:
4418                                 panic("invalid akind in mode attribute");
4419                         }
4420                 }
4421                 declaration->type
4422                         = make_atomic_type(akind, old_type->base.qualifiers);
4423         }
4424 }
4425
4426 static type_t *construct_declarator_type(construct_type_t *construct_list,
4427                                          type_t *type)
4428 {
4429         construct_type_t *iter = construct_list;
4430         for( ; iter != NULL; iter = iter->next) {
4431                 switch(iter->kind) {
4432                 case CONSTRUCT_INVALID:
4433                         internal_errorf(HERE, "invalid type construction found");
4434                 case CONSTRUCT_FUNCTION: {
4435                         construct_function_type_t *construct_function_type
4436                                 = (construct_function_type_t*) iter;
4437
4438                         type_t *function_type = construct_function_type->function_type;
4439
4440                         function_type->function.return_type = type;
4441
4442                         type_t *skipped_return_type = skip_typeref(type);
4443                         /* §6.7.5.3(1) */
4444                         if (is_type_function(skipped_return_type)) {
4445                                 errorf(HERE, "function returning function is not allowed");
4446                         } else if (is_type_array(skipped_return_type)) {
4447                                 errorf(HERE, "function returning array is not allowed");
4448                         } else {
4449                                 if (skipped_return_type->base.qualifiers != 0 && warning.other) {
4450                                         warningf(HERE,
4451                                                 "type qualifiers in return type of function type are meaningless");
4452                                 }
4453                         }
4454
4455                         type = function_type;
4456                         break;
4457                 }
4458
4459                 case CONSTRUCT_POINTER: {
4460                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
4461                         type = make_pointer_type(type, parsed_pointer->type_qualifiers);
4462                         continue;
4463                 }
4464
4465                 case CONSTRUCT_ARRAY: {
4466                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
4467                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY);
4468
4469                         expression_t *size_expression = parsed_array->size;
4470                         if (size_expression != NULL) {
4471                                 size_expression
4472                                         = create_implicit_cast(size_expression, type_size_t);
4473                         }
4474
4475                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
4476                         array_type->array.element_type    = type;
4477                         array_type->array.is_static       = parsed_array->is_static;
4478                         array_type->array.is_variable     = parsed_array->is_variable;
4479                         array_type->array.size_expression = size_expression;
4480
4481                         if (size_expression != NULL) {
4482                                 if (is_constant_expression(size_expression)) {
4483                                         array_type->array.size_constant = true;
4484                                         array_type->array.size
4485                                                 = fold_constant(size_expression);
4486                                 } else {
4487                                         array_type->array.is_vla = true;
4488                                 }
4489                         }
4490
4491                         type_t *skipped_type = skip_typeref(type);
4492                         /* §6.7.5.2(1) */
4493                         if (is_type_incomplete(skipped_type)) {
4494                                 errorf(HERE, "array of incomplete type '%T' is not allowed", type);
4495                         } else if (is_type_function(skipped_type)) {
4496                                 errorf(HERE, "array of functions is not allowed");
4497                         }
4498                         type = array_type;
4499                         break;
4500                 }
4501                 }
4502
4503                 type_t *hashed_type = typehash_insert(type);
4504                 if (hashed_type != type) {
4505                         /* the function type was constructed earlier freeing it here will
4506                          * destroy other types... */
4507                         if (iter->kind != CONSTRUCT_FUNCTION) {
4508                                 free_type(type);
4509                         }
4510                         type = hashed_type;
4511                 }
4512         }
4513
4514         return type;
4515 }
4516
4517 static declaration_t *parse_declarator(
4518                 const declaration_specifiers_t *specifiers, bool may_be_abstract)
4519 {
4520         declaration_t *const declaration    = allocate_declaration_zero();
4521         declaration->source_position        = specifiers->source_position;
4522         declaration->declared_storage_class = specifiers->declared_storage_class;
4523         declaration->modifiers              = specifiers->modifiers;
4524         declaration->deprecated_string      = specifiers->deprecated_string;
4525         declaration->get_property_sym       = specifiers->get_property_sym;
4526         declaration->put_property_sym       = specifiers->put_property_sym;
4527         declaration->is_inline              = specifiers->is_inline;
4528
4529         declaration->storage_class          = specifiers->declared_storage_class;
4530         if (declaration->storage_class == STORAGE_CLASS_NONE &&
4531             scope != file_scope) {
4532                 declaration->storage_class = STORAGE_CLASS_AUTO;
4533         }
4534
4535         if (specifiers->alignment != 0) {
4536                 /* TODO: add checks here */
4537                 declaration->alignment = specifiers->alignment;
4538         }
4539
4540         construct_type_t *construct_type
4541                 = parse_inner_declarator(declaration, may_be_abstract);
4542         type_t *const type = specifiers->type;
4543         declaration->type = construct_declarator_type(construct_type, type);
4544
4545         parse_declaration_attributes(declaration);
4546
4547         fix_declaration_type(declaration);
4548
4549         if (construct_type != NULL) {
4550                 obstack_free(&temp_obst, construct_type);
4551         }
4552
4553         return declaration;
4554 }
4555
4556 static type_t *parse_abstract_declarator(type_t *base_type)
4557 {
4558         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4559
4560         type_t *result = construct_declarator_type(construct_type, base_type);
4561         if (construct_type != NULL) {
4562                 obstack_free(&temp_obst, construct_type);
4563         }
4564
4565         return result;
4566 }
4567
4568 static declaration_t *append_declaration(declaration_t* const declaration)
4569 {
4570         if (last_declaration != NULL) {
4571                 last_declaration->next = declaration;
4572         } else {
4573                 scope->declarations = declaration;
4574         }
4575         last_declaration = declaration;
4576         return declaration;
4577 }
4578
4579 /**
4580  * Check if the declaration of main is suspicious.  main should be a
4581  * function with external linkage, returning int, taking either zero
4582  * arguments, two, or three arguments of appropriate types, ie.
4583  *
4584  * int main([ int argc, char **argv [, char **env ] ]).
4585  *
4586  * @param decl    the declaration to check
4587  * @param type    the function type of the declaration
4588  */
4589 static void check_type_of_main(const declaration_t *const decl, const function_type_t *const func_type)
4590 {
4591         if (decl->storage_class == STORAGE_CLASS_STATIC) {
4592                 warningf(&decl->source_position,
4593                          "'main' is normally a non-static function");
4594         }
4595         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4596                 warningf(&decl->source_position,
4597                          "return type of 'main' should be 'int', but is '%T'",
4598                          func_type->return_type);
4599         }
4600         const function_parameter_t *parm = func_type->parameters;
4601         if (parm != NULL) {
4602                 type_t *const first_type = parm->type;
4603                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4604                         warningf(&decl->source_position,
4605                                  "first argument of 'main' should be 'int', but is '%T'", first_type);
4606                 }
4607                 parm = parm->next;
4608                 if (parm != NULL) {
4609                         type_t *const second_type = parm->type;
4610                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4611                                 warningf(&decl->source_position,
4612                                          "second argument of 'main' should be 'char**', but is '%T'", second_type);
4613                         }
4614                         parm = parm->next;
4615                         if (parm != NULL) {
4616                                 type_t *const third_type = parm->type;
4617                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4618                                         warningf(&decl->source_position,
4619                                                  "third argument of 'main' should be 'char**', but is '%T'", third_type);
4620                                 }
4621                                 parm = parm->next;
4622                                 if (parm != NULL)
4623                                         goto warn_arg_count;
4624                         }
4625                 } else {
4626 warn_arg_count:
4627                         warningf(&decl->source_position, "'main' takes only zero, two or three arguments");
4628                 }
4629         }
4630 }
4631
4632 /**
4633  * Check if a symbol is the equal to "main".
4634  */
4635 static bool is_sym_main(const symbol_t *const sym)
4636 {
4637         return strcmp(sym->string, "main") == 0;
4638 }
4639
4640 static declaration_t *record_declaration(
4641         declaration_t *const declaration,
4642         const bool is_definition)
4643 {
4644         const symbol_t *const symbol  = declaration->symbol;
4645         const namespace_t     namespc = (namespace_t)declaration->namespc;
4646
4647         assert(symbol != NULL);
4648         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4649
4650         type_t *const orig_type = declaration->type;
4651         type_t *const type      = skip_typeref(orig_type);
4652         if (is_type_function(type) &&
4653                         type->function.unspecified_parameters &&
4654                         warning.strict_prototypes &&
4655                         previous_declaration == NULL) {
4656                 warningf(&declaration->source_position,
4657                          "function declaration '%#T' is not a prototype",
4658                          orig_type, symbol);
4659         }
4660
4661         if (warning.main && is_type_function(type) && is_sym_main(symbol)) {
4662                 check_type_of_main(declaration, &type->function);
4663         }
4664
4665         if (warning.nested_externs                             &&
4666             declaration->storage_class == STORAGE_CLASS_EXTERN &&
4667             scope                      != file_scope) {
4668                 warningf(&declaration->source_position,
4669                          "nested extern declaration of '%#T'", declaration->type, symbol);
4670         }
4671
4672         assert(declaration != previous_declaration);
4673         if (previous_declaration != NULL &&
4674             previous_declaration->parent_scope == &current_function->scope &&
4675             scope->depth == previous_declaration->parent_scope->depth + 1) {
4676                 errorf(&declaration->source_position,
4677                         "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
4678                         orig_type, symbol, previous_declaration->type, symbol,
4679                         &previous_declaration->source_position);
4680                 goto finish;
4681         }
4682         if (previous_declaration != NULL &&
4683             previous_declaration->parent_scope == scope) {
4684                 /* can happen for K&R style declarations */
4685                 if (previous_declaration->type == NULL) {
4686                         previous_declaration->type = declaration->type;
4687                 }
4688
4689                 const type_t *prev_type = skip_typeref(previous_declaration->type);
4690                 if (!types_compatible(type, prev_type)) {
4691                         errorf(&declaration->source_position,
4692                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
4693                                    orig_type, symbol, previous_declaration->type, symbol,
4694                                    &previous_declaration->source_position);
4695                 } else {
4696                         unsigned old_storage_class = previous_declaration->storage_class;
4697                         if (old_storage_class == STORAGE_CLASS_ENUM_ENTRY) {
4698                                 errorf(&declaration->source_position,
4699                                            "redeclaration of enum entry '%Y' (declared %P)",
4700                                            symbol, &previous_declaration->source_position);
4701                                 return previous_declaration;
4702                         }
4703
4704                         if (warning.redundant_decls                                     &&
4705                             is_definition                                               &&
4706                             previous_declaration->storage_class == STORAGE_CLASS_STATIC &&
4707                             !(previous_declaration->modifiers & DM_USED)                &&
4708                             !previous_declaration->used) {
4709                                 warningf(&previous_declaration->source_position,
4710                                          "unnecessary static forward declaration for '%#T'",
4711                                          previous_declaration->type, symbol);
4712                         }
4713
4714                         unsigned new_storage_class = declaration->storage_class;
4715
4716                         if (is_type_incomplete(prev_type)) {
4717                                 previous_declaration->type = type;
4718                                 prev_type                  = type;
4719                         }
4720
4721                         /* pretend no storage class means extern for function
4722                          * declarations (except if the previous declaration is neither
4723                          * none nor extern) */
4724                         if (is_type_function(type)) {
4725                                 if (prev_type->function.unspecified_parameters) {
4726                                         previous_declaration->type = type;
4727                                         prev_type                  = type;
4728                                 }
4729
4730                                 switch (old_storage_class) {
4731                                 case STORAGE_CLASS_NONE:
4732                                         old_storage_class = STORAGE_CLASS_EXTERN;
4733                                         /* FALLTHROUGH */
4734
4735                                 case STORAGE_CLASS_EXTERN:
4736                                         if (is_definition) {
4737                                                 if (warning.missing_prototypes &&
4738                                                     prev_type->function.unspecified_parameters &&
4739                                                     !is_sym_main(symbol)) {
4740                                                         warningf(&declaration->source_position,
4741                                                                          "no previous prototype for '%#T'",
4742                                                                          orig_type, symbol);
4743                                                 }
4744                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4745                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4746                                         }
4747                                         break;
4748
4749                                 default:
4750                                         break;
4751                                 }
4752                         }
4753
4754                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
4755                                         new_storage_class == STORAGE_CLASS_EXTERN) {
4756 warn_redundant_declaration:
4757                                 if (!is_definition           &&
4758                                     warning.redundant_decls  &&
4759                                     is_type_valid(prev_type) &&
4760                                     strcmp(previous_declaration->source_position.input_name, "<builtin>") != 0) {
4761                                         warningf(&declaration->source_position,
4762                                                  "redundant declaration for '%Y' (declared %P)",
4763                                                  symbol, &previous_declaration->source_position);
4764                                 }
4765                         } else if (current_function == NULL) {
4766                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
4767                                     new_storage_class == STORAGE_CLASS_STATIC) {
4768                                         errorf(&declaration->source_position,
4769                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
4770                                                symbol, &previous_declaration->source_position);
4771                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4772                                         previous_declaration->storage_class          = STORAGE_CLASS_NONE;
4773                                         previous_declaration->declared_storage_class = STORAGE_CLASS_NONE;
4774                                 } else {
4775                                         goto warn_redundant_declaration;
4776                                 }
4777                         } else if (is_type_valid(prev_type)) {
4778                                 if (old_storage_class == new_storage_class) {
4779                                         errorf(&declaration->source_position,
4780                                                "redeclaration of '%Y' (declared %P)",
4781                                                symbol, &previous_declaration->source_position);
4782                                 } else {
4783                                         errorf(&declaration->source_position,
4784                                                "redeclaration of '%Y' with different linkage (declared %P)",
4785                                                symbol, &previous_declaration->source_position);
4786                                 }
4787                         }
4788                 }
4789
4790                 previous_declaration->modifiers |= declaration->modifiers;
4791                 previous_declaration->is_inline |= declaration->is_inline;
4792                 return previous_declaration;
4793         } else if (is_type_function(type)) {
4794                 if (is_definition &&
4795                     declaration->storage_class != STORAGE_CLASS_STATIC) {
4796                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4797                                 warningf(&declaration->source_position,
4798                                          "no previous prototype for '%#T'", orig_type, symbol);
4799                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4800                                 warningf(&declaration->source_position,
4801                                          "no previous declaration for '%#T'", orig_type,
4802                                          symbol);
4803                         }
4804                 }
4805         } else {
4806                 if (warning.missing_declarations &&
4807                     scope == file_scope && (
4808                       declaration->storage_class == STORAGE_CLASS_NONE ||
4809                       declaration->storage_class == STORAGE_CLASS_THREAD
4810                     )) {
4811                         warningf(&declaration->source_position,
4812                                  "no previous declaration for '%#T'", orig_type, symbol);
4813                 }
4814         }
4815 finish:
4816         assert(declaration->parent_scope == NULL);
4817         assert(scope != NULL);
4818
4819         declaration->parent_scope = scope;
4820
4821         environment_push(declaration);
4822         return append_declaration(declaration);
4823 }
4824
4825 static void parser_error_multiple_definition(declaration_t *declaration,
4826                 const source_position_t *source_position)
4827 {
4828         errorf(source_position, "multiple definition of symbol '%Y' (declared %P)",
4829                declaration->symbol, &declaration->source_position);
4830 }
4831
4832 static bool is_declaration_specifier(const token_t *token,
4833                                      bool only_specifiers_qualifiers)
4834 {
4835         switch (token->type) {
4836                 TYPE_SPECIFIERS
4837                 TYPE_QUALIFIERS
4838                         return true;
4839                 case T_IDENTIFIER:
4840                         return is_typedef_symbol(token->v.symbol);
4841
4842                 case T___extension__:
4843                 STORAGE_CLASSES
4844                         return !only_specifiers_qualifiers;
4845
4846                 default:
4847                         return false;
4848         }
4849 }
4850
4851 static void parse_init_declarator_rest(declaration_t *declaration)
4852 {
4853         eat('=');
4854
4855         type_t *orig_type = declaration->type;
4856         type_t *type      = skip_typeref(orig_type);
4857
4858         if (declaration->init.initializer != NULL) {
4859                 parser_error_multiple_definition(declaration, HERE);
4860         }
4861
4862         bool must_be_constant = false;
4863         if (declaration->storage_class == STORAGE_CLASS_STATIC        ||
4864             declaration->storage_class == STORAGE_CLASS_THREAD_STATIC ||
4865             declaration->parent_scope  == file_scope) {
4866                 must_be_constant = true;
4867         }
4868
4869         if (is_type_function(type)) {
4870                 errorf(&declaration->source_position,
4871                        "function '%#T' is initialized like a variable",
4872                        orig_type, declaration->symbol);
4873                 orig_type = type_error_type;
4874         }
4875
4876         parse_initializer_env_t env;
4877         env.type             = orig_type;
4878         env.must_be_constant = must_be_constant;
4879         env.declaration      = current_init_decl = declaration;
4880
4881         initializer_t *initializer = parse_initializer(&env);
4882         current_init_decl = NULL;
4883
4884         if (!is_type_function(type)) {
4885                 /* § 6.7.5 (22)  array initializers for arrays with unknown size determine
4886                  * the array type size */
4887                 declaration->type             = env.type;
4888                 declaration->init.initializer = initializer;
4889         }
4890 }
4891
4892 /* parse rest of a declaration without any declarator */
4893 static void parse_anonymous_declaration_rest(
4894                 const declaration_specifiers_t *specifiers)
4895 {
4896         eat(';');
4897
4898         if (warning.other) {
4899                 if (specifiers->declared_storage_class != STORAGE_CLASS_NONE) {
4900                         warningf(&specifiers->source_position,
4901                                  "useless storage class in empty declaration");
4902                 }
4903
4904                 type_t *type = specifiers->type;
4905                 switch (type->kind) {
4906                         case TYPE_COMPOUND_STRUCT:
4907                         case TYPE_COMPOUND_UNION: {
4908                                 if (type->compound.declaration->symbol == NULL) {
4909                                         warningf(&specifiers->source_position,
4910                                                  "unnamed struct/union that defines no instances");
4911                                 }
4912                                 break;
4913                         }
4914
4915                         case TYPE_ENUM:
4916                                 break;
4917
4918                         default:
4919                                 warningf(&specifiers->source_position, "empty declaration");
4920                                 break;
4921                 }
4922         }
4923
4924 #ifdef RECORD_EMPTY_DECLARATIONS
4925         declaration_t *const declaration    = allocate_declaration_zero();
4926         declaration->type                   = specifiers->type;
4927         declaration->declared_storage_class = specifiers->declared_storage_class;
4928         declaration->source_position        = specifiers->source_position;
4929         declaration->modifiers              = specifiers->modifiers;
4930         declaration->storage_class          = STORAGE_CLASS_NONE;
4931
4932         append_declaration(declaration);
4933 #endif
4934 }
4935
4936 static void parse_declaration_rest(declaration_t *ndeclaration,
4937                 const declaration_specifiers_t *specifiers,
4938                 parsed_declaration_func finished_declaration)
4939 {
4940         add_anchor_token(';');
4941         add_anchor_token(',');
4942         while(true) {
4943                 declaration_t *declaration =
4944                         finished_declaration(ndeclaration, token.type == '=');
4945
4946                 type_t *orig_type = declaration->type;
4947                 type_t *type      = skip_typeref(orig_type);
4948
4949                 if (warning.other               &&
4950                                 type->kind != TYPE_FUNCTION &&
4951                     declaration->is_inline      &&
4952                     is_type_valid(type)) {
4953                         warningf(&declaration->source_position,
4954                                  "variable '%Y' declared 'inline'\n", declaration->symbol);
4955                 }
4956
4957                 if (token.type == '=') {
4958                         parse_init_declarator_rest(declaration);
4959                 }
4960
4961                 if (token.type != ',')
4962                         break;
4963                 eat(',');
4964
4965                 add_anchor_token('=');
4966                 ndeclaration = parse_declarator(specifiers, /*may_be_abstract=*/false);
4967                 rem_anchor_token('=');
4968         }
4969         expect(';');
4970
4971 end_error:
4972         rem_anchor_token(';');
4973         rem_anchor_token(',');
4974 }
4975
4976 static declaration_t *finished_kr_declaration(declaration_t *declaration, bool is_definition)
4977 {
4978         symbol_t *symbol  = declaration->symbol;
4979         if (symbol == NULL) {
4980                 errorf(HERE, "anonymous declaration not valid as function parameter");
4981                 return declaration;
4982         }
4983         namespace_t namespc = (namespace_t) declaration->namespc;
4984         if (namespc != NAMESPACE_NORMAL) {
4985                 return record_declaration(declaration, false);
4986         }
4987
4988         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4989         if (previous_declaration == NULL ||
4990                         previous_declaration->parent_scope != scope) {
4991                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
4992                        symbol);
4993                 return declaration;
4994         }
4995
4996         if (is_definition) {
4997                 errorf(HERE, "parameter %Y is initialised", declaration->symbol);
4998         }
4999
5000         if (previous_declaration->type == NULL) {
5001                 previous_declaration->type          = declaration->type;
5002                 previous_declaration->declared_storage_class = declaration->declared_storage_class;
5003                 previous_declaration->storage_class = declaration->storage_class;
5004                 previous_declaration->parent_scope  = scope;
5005                 return previous_declaration;
5006         } else {
5007                 return record_declaration(declaration, false);
5008         }
5009 }
5010
5011 static void parse_declaration(parsed_declaration_func finished_declaration)
5012 {
5013         declaration_specifiers_t specifiers;
5014         memset(&specifiers, 0, sizeof(specifiers));
5015
5016         add_anchor_token(';');
5017         parse_declaration_specifiers(&specifiers);
5018         rem_anchor_token(';');
5019
5020         if (token.type == ';') {
5021                 parse_anonymous_declaration_rest(&specifiers);
5022         } else {
5023                 declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
5024                 parse_declaration_rest(declaration, &specifiers, finished_declaration);
5025         }
5026 }
5027
5028 static type_t *get_default_promoted_type(type_t *orig_type)
5029 {
5030         type_t *result = orig_type;
5031
5032         type_t *type = skip_typeref(orig_type);
5033         if (is_type_integer(type)) {
5034                 result = promote_integer(type);
5035         } else if (type == type_float) {
5036                 result = type_double;
5037         }
5038
5039         return result;
5040 }
5041
5042 static void parse_kr_declaration_list(declaration_t *declaration)
5043 {
5044         type_t *type = skip_typeref(declaration->type);
5045         if (!is_type_function(type))
5046                 return;
5047
5048         if (!type->function.kr_style_parameters)
5049                 return;
5050
5051         add_anchor_token('{');
5052
5053         /* push function parameters */
5054         size_t const top = environment_top();
5055         scope_push(&declaration->scope);
5056
5057         declaration_t *parameter = declaration->scope.declarations;
5058         for ( ; parameter != NULL; parameter = parameter->next) {
5059                 assert(parameter->parent_scope == NULL);
5060                 parameter->parent_scope = scope;
5061                 environment_push(parameter);
5062         }
5063
5064         /* parse declaration list */
5065         while (is_declaration_specifier(&token, false)) {
5066                 parse_declaration(finished_kr_declaration);
5067         }
5068
5069         /* pop function parameters */
5070         assert(scope == &declaration->scope);
5071         scope_pop();
5072         environment_pop_to(top);
5073
5074         /* update function type */
5075         type_t *new_type = duplicate_type(type);
5076
5077         function_parameter_t *parameters     = NULL;
5078         function_parameter_t *last_parameter = NULL;
5079
5080         declaration_t *parameter_declaration = declaration->scope.declarations;
5081         for( ; parameter_declaration != NULL;
5082                         parameter_declaration = parameter_declaration->next) {
5083                 type_t *parameter_type = parameter_declaration->type;
5084                 if (parameter_type == NULL) {
5085                         if (strict_mode) {
5086                                 errorf(HERE, "no type specified for function parameter '%Y'",
5087                                        parameter_declaration->symbol);
5088                         } else {
5089                                 if (warning.implicit_int) {
5090                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
5091                                                 parameter_declaration->symbol);
5092                                 }
5093                                 parameter_type              = type_int;
5094                                 parameter_declaration->type = parameter_type;
5095                         }
5096                 }
5097
5098                 semantic_parameter(parameter_declaration);
5099                 parameter_type = parameter_declaration->type;
5100
5101                 /*
5102                  * we need the default promoted types for the function type
5103                  */
5104                 parameter_type = get_default_promoted_type(parameter_type);
5105
5106                 function_parameter_t *function_parameter
5107                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
5108                 memset(function_parameter, 0, sizeof(function_parameter[0]));
5109
5110                 function_parameter->type = parameter_type;
5111                 if (last_parameter != NULL) {
5112                         last_parameter->next = function_parameter;
5113                 } else {
5114                         parameters = function_parameter;
5115                 }
5116                 last_parameter = function_parameter;
5117         }
5118
5119         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
5120          * prototype */
5121         new_type->function.parameters             = parameters;
5122         new_type->function.unspecified_parameters = true;
5123
5124         type = typehash_insert(new_type);
5125         if (type != new_type) {
5126                 obstack_free(type_obst, new_type);
5127         }
5128
5129         declaration->type = type;
5130
5131         rem_anchor_token('{');
5132 }
5133
5134 static bool first_err = true;
5135
5136 /**
5137  * When called with first_err set, prints the name of the current function,
5138  * else does noting.
5139  */
5140 static void print_in_function(void)
5141 {
5142         if (first_err) {
5143                 first_err = false;
5144                 diagnosticf("%s: In function '%Y':\n",
5145                         current_function->source_position.input_name,
5146                         current_function->symbol);
5147         }
5148 }
5149
5150 /**
5151  * Check if all labels are defined in the current function.
5152  * Check if all labels are used in the current function.
5153  */
5154 static void check_labels(void)
5155 {
5156         for (const goto_statement_t *goto_statement = goto_first;
5157             goto_statement != NULL;
5158             goto_statement = goto_statement->next) {
5159                 /* skip computed gotos */
5160                 if (goto_statement->expression != NULL)
5161                         continue;
5162
5163                 declaration_t *label = goto_statement->label;
5164
5165                 label->used = true;
5166                 if (label->source_position.input_name == NULL) {
5167                         print_in_function();
5168                         errorf(&goto_statement->base.source_position,
5169                                "label '%Y' used but not defined", label->symbol);
5170                  }
5171         }
5172         goto_first = goto_last = NULL;
5173
5174         if (warning.unused_label) {
5175                 for (const label_statement_t *label_statement = label_first;
5176                          label_statement != NULL;
5177                          label_statement = label_statement->next) {
5178                         const declaration_t *label = label_statement->label;
5179
5180                         if (! label->used) {
5181                                 print_in_function();
5182                                 warningf(&label_statement->base.source_position,
5183                                         "label '%Y' defined but not used", label->symbol);
5184                         }
5185                 }
5186         }
5187         label_first = label_last = NULL;
5188 }
5189
5190 static void warn_unused_decl(declaration_t *decl, declaration_t *end, char const *const what)
5191 {
5192         for (; decl != NULL; decl = decl->next) {
5193                 if (decl->implicit)
5194                         continue;
5195
5196                 if (!decl->used) {
5197                         print_in_function();
5198                         warningf(&decl->source_position, "%s '%Y' is unused", what, decl->symbol);
5199                 } else if (!decl->read) {
5200                         print_in_function();
5201                         warningf(&decl->source_position, "%s '%Y' is never read", what, decl->symbol);
5202                 }
5203
5204                 if (decl == end)
5205                         break;
5206         }
5207 }
5208
5209 static void check_unused_variables(statement_t *const stmt, void *const env)
5210 {
5211         (void)env;
5212
5213         switch (stmt->kind) {
5214                 case STATEMENT_DECLARATION: {
5215                         declaration_statement_t const *const decls = &stmt->declaration;
5216                         warn_unused_decl(decls->declarations_begin, decls->declarations_end, "variable");
5217                         return;
5218                 }
5219
5220                 case STATEMENT_FOR:
5221                         warn_unused_decl(stmt->fors.scope.declarations, NULL, "variable");
5222                         return;
5223
5224                 default:
5225                         return;
5226         }
5227 }
5228
5229 /**
5230  * Check declarations of current_function for unused entities.
5231  */
5232 static void check_declarations(void)
5233 {
5234         if (warning.unused_parameter) {
5235                 const scope_t *scope = &current_function->scope;
5236
5237                 /* do not issue unused warnings for main */
5238                 if (!is_sym_main(current_function->symbol)) {
5239                         warn_unused_decl(scope->declarations, NULL, "parameter");
5240                 }
5241         }
5242         if (warning.unused_variable) {
5243                 walk_statements(current_function->init.statement, check_unused_variables, NULL);
5244         }
5245 }
5246
5247 static int determine_truth(expression_t const* const cond)
5248 {
5249         return
5250                 !is_constant_expression(cond) ? 0 :
5251                 fold_constant(cond) != 0      ? 1 :
5252                 -1;
5253 }
5254
5255 static bool expression_returns(expression_t const *const expr)
5256 {
5257         switch (expr->kind) {
5258                 case EXPR_CALL: {
5259                         expression_t const *const func = expr->call.function;
5260                         if (func->kind == EXPR_REFERENCE) {
5261                                 declaration_t const *const decl = func->reference.declaration;
5262                                 if (decl != NULL && decl->modifiers & DM_NORETURN)
5263                                         return false;
5264                         }
5265
5266                         if (!expression_returns(func))
5267                                 return false;
5268
5269                         for (call_argument_t const* arg = expr->call.arguments; arg != NULL; arg = arg->next) {
5270                                 if (!expression_returns(arg->expression))
5271                                         return false;
5272                         }
5273
5274                         return true;
5275                 }
5276
5277                 case EXPR_REFERENCE:
5278                 case EXPR_CONST:
5279                 case EXPR_CHARACTER_CONSTANT:
5280                 case EXPR_WIDE_CHARACTER_CONSTANT:
5281                 case EXPR_STRING_LITERAL:
5282                 case EXPR_WIDE_STRING_LITERAL:
5283                 case EXPR_COMPOUND_LITERAL: // TODO descend into initialisers
5284                 case EXPR_LABEL_ADDRESS:
5285                 case EXPR_CLASSIFY_TYPE:
5286                 case EXPR_SIZEOF: // TODO handle obscure VLA case
5287                 case EXPR_ALIGNOF:
5288                 case EXPR_FUNCNAME:
5289                 case EXPR_BUILTIN_SYMBOL:
5290                 case EXPR_BUILTIN_CONSTANT_P:
5291                 case EXPR_BUILTIN_PREFETCH:
5292                 case EXPR_OFFSETOF:
5293                 case EXPR_STATEMENT: // TODO implement
5294                         return true;
5295
5296                 case EXPR_CONDITIONAL:
5297                         // TODO handle constant expression
5298                         return
5299                                 expression_returns(expr->conditional.condition) && (
5300                                         expression_returns(expr->conditional.true_expression) ||
5301                                         expression_returns(expr->conditional.false_expression)
5302                                 );
5303
5304                 case EXPR_SELECT:
5305                         return expression_returns(expr->select.compound);
5306
5307                 case EXPR_ARRAY_ACCESS:
5308                         return
5309                                 expression_returns(expr->array_access.array_ref) &&
5310                                 expression_returns(expr->array_access.index);
5311
5312                 case EXPR_VA_START:
5313                         return expression_returns(expr->va_starte.ap);
5314
5315                 case EXPR_VA_ARG:
5316                         return expression_returns(expr->va_arge.ap);
5317
5318                 EXPR_UNARY_CASES_MANDATORY
5319                         return expression_returns(expr->unary.value);
5320
5321                 case EXPR_UNARY_THROW:
5322                         return false;
5323
5324                 EXPR_BINARY_CASES
5325                         // TODO handle constant lhs of && and ||
5326                         return
5327                                 expression_returns(expr->binary.left) &&
5328                                 expression_returns(expr->binary.right);
5329
5330                 case EXPR_UNKNOWN:
5331                 case EXPR_INVALID:
5332                         break;
5333         }
5334
5335         panic("unhandled expression");
5336 }
5337
5338 static bool noreturn_candidate;
5339
5340 static void check_reachable(statement_t *const stmt)
5341 {
5342         if (stmt->base.reachable)
5343                 return;
5344         if (stmt->kind != STATEMENT_DO_WHILE)
5345                 stmt->base.reachable = true;
5346
5347         statement_t *last = stmt;
5348         statement_t *next;
5349         switch (stmt->kind) {
5350                 case STATEMENT_INVALID:
5351                 case STATEMENT_EMPTY:
5352                 case STATEMENT_DECLARATION:
5353                 case STATEMENT_ASM:
5354                         next = stmt->base.next;
5355                         break;
5356
5357                 case STATEMENT_COMPOUND:
5358                         next = stmt->compound.statements;
5359                         break;
5360
5361                 case STATEMENT_RETURN:
5362                         noreturn_candidate = false;
5363                         return;
5364
5365                 case STATEMENT_IF: {
5366                         if_statement_t const* const ifs = &stmt->ifs;
5367                         int            const        val = determine_truth(ifs->condition);
5368
5369                         if (val >= 0)
5370                                 check_reachable(ifs->true_statement);
5371
5372                         if (val > 0)
5373                                 return;
5374
5375                         if (ifs->false_statement != NULL) {
5376                                 check_reachable(ifs->false_statement);
5377                                 return;
5378                         }
5379
5380                         next = stmt->base.next;
5381                         break;
5382                 }
5383
5384                 case STATEMENT_SWITCH: {
5385                         switch_statement_t const *const switchs = &stmt->switchs;
5386                         expression_t       const *const expr    = switchs->expression;
5387
5388                         if (is_constant_expression(expr)) {
5389                                 long                    const val      = fold_constant(expr);
5390                                 case_label_statement_t *      defaults = NULL;
5391                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5392                                         if (i->expression == NULL) {
5393                                                 defaults = i;
5394                                                 continue;
5395                                         }
5396
5397                                         if (i->first_case <= val && val <= i->last_case) {
5398                                                 check_reachable((statement_t*)i);
5399                                                 return;
5400                                         }
5401                                 }
5402
5403                                 if (defaults != NULL) {
5404                                         check_reachable((statement_t*)defaults);
5405                                         return;
5406                                 }
5407                         } else {
5408                                 bool has_default = false;
5409                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5410                                         if (i->expression == NULL)
5411                                                 has_default = true;
5412
5413                                         check_reachable((statement_t*)i);
5414                                 }
5415
5416                                 if (has_default)
5417                                         return;
5418                         }
5419
5420                         next = stmt->base.next;
5421                         break;
5422                 }
5423
5424                 case STATEMENT_EXPRESSION: {
5425                         /* Check for noreturn function call */
5426                         expression_t const *const expr = stmt->expression.expression;
5427                         if (!expression_returns(expr))
5428                                 return;
5429
5430                         next = stmt->base.next;
5431                         break;
5432                 }
5433
5434                 case STATEMENT_CONTINUE: {
5435                         statement_t *parent = stmt;
5436                         for (;;) {
5437                                 parent = parent->base.parent;
5438                                 if (parent == NULL) /* continue not within loop */
5439                                         return;
5440
5441                                 next = parent;
5442                                 switch (parent->kind) {
5443                                         case STATEMENT_WHILE:    goto continue_while;
5444                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5445                                         case STATEMENT_FOR:      goto continue_for;
5446
5447                                         default: break;
5448                                 }
5449                         }
5450                 }
5451
5452                 case STATEMENT_BREAK: {
5453                         statement_t *parent = stmt;
5454                         for (;;) {
5455                                 parent = parent->base.parent;
5456                                 if (parent == NULL) /* break not within loop/switch */
5457                                         return;
5458
5459                                 switch (parent->kind) {
5460                                         case STATEMENT_SWITCH:
5461                                         case STATEMENT_WHILE:
5462                                         case STATEMENT_DO_WHILE:
5463                                         case STATEMENT_FOR:
5464                                                 last = parent;
5465                                                 next = parent->base.next;
5466                                                 goto found_break_parent;
5467
5468                                         default: break;
5469                                 }
5470                         }
5471 found_break_parent:
5472                         break;
5473                 }
5474
5475                 case STATEMENT_GOTO:
5476                         if (stmt->gotos.expression) {
5477                                 statement_t *parent = stmt->base.parent;
5478                                 if (parent == NULL) /* top level goto */
5479                                         return;
5480                                 next = parent;
5481                         } else {
5482                                 next = stmt->gotos.label->init.statement;
5483                                 if (next == NULL) /* missing label */
5484                                         return;
5485                         }
5486                         break;
5487
5488                 case STATEMENT_LABEL:
5489                         next = stmt->label.statement;
5490                         break;
5491
5492                 case STATEMENT_CASE_LABEL:
5493                         next = stmt->case_label.statement;
5494                         break;
5495
5496                 case STATEMENT_WHILE: {
5497                         while_statement_t const *const whiles = &stmt->whiles;
5498                         int                      const val    = determine_truth(whiles->condition);
5499
5500                         if (val >= 0)
5501                                 check_reachable(whiles->body);
5502
5503                         if (val > 0)
5504                                 return;
5505
5506                         next = stmt->base.next;
5507                         break;
5508                 }
5509
5510                 case STATEMENT_DO_WHILE:
5511                         next = stmt->do_while.body;
5512                         break;
5513
5514                 case STATEMENT_FOR: {
5515                         for_statement_t *const fors = &stmt->fors;
5516
5517                         if (fors->condition_reachable)
5518                                 return;
5519                         fors->condition_reachable = true;
5520
5521                         expression_t const *const cond = fors->condition;
5522                         int          const        val  =
5523                                 cond == NULL ? 1 : determine_truth(cond);
5524
5525                         if (val >= 0)
5526                                 check_reachable(fors->body);
5527
5528                         if (val > 0)
5529                                 return;
5530
5531                         next = stmt->base.next;
5532                         break;
5533                 }
5534
5535                 case STATEMENT_MS_TRY: {
5536                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
5537                         check_reachable(ms_try->try_statement);
5538                         next = ms_try->final_statement;
5539                         break;
5540                 }
5541
5542                 case STATEMENT_LEAVE: {
5543                         statement_t *parent = stmt;
5544                         for (;;) {
5545                                 parent = parent->base.parent;
5546                                 if (parent == NULL) /* __leave not within __try */
5547                                         return;
5548
5549                                 if (parent->kind == STATEMENT_MS_TRY) {
5550                                         last = parent;
5551                                         next = parent->ms_try.final_statement;
5552                                         break;
5553                                 }
5554                         }
5555                         break;
5556                 }
5557         }
5558
5559         while (next == NULL) {
5560                 next = last->base.parent;
5561                 if (next == NULL) {
5562                         noreturn_candidate = false;
5563
5564                         type_t *const type = current_function->type;
5565                         assert(is_type_function(type));
5566                         type_t *const ret  = skip_typeref(type->function.return_type);
5567                         if (warning.return_type                    &&
5568                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
5569                             is_type_valid(ret)                     &&
5570                             !is_sym_main(current_function->symbol)) {
5571                                 warningf(&stmt->base.source_position,
5572                                          "control reaches end of non-void function");
5573                         }
5574                         return;
5575                 }
5576
5577                 switch (next->kind) {
5578                         case STATEMENT_INVALID:
5579                         case STATEMENT_EMPTY:
5580                         case STATEMENT_DECLARATION:
5581                         case STATEMENT_EXPRESSION:
5582                         case STATEMENT_ASM:
5583                         case STATEMENT_RETURN:
5584                         case STATEMENT_CONTINUE:
5585                         case STATEMENT_BREAK:
5586                         case STATEMENT_GOTO:
5587                         case STATEMENT_LEAVE:
5588                                 panic("invalid control flow in function");
5589
5590                         case STATEMENT_COMPOUND:
5591                         case STATEMENT_IF:
5592                         case STATEMENT_SWITCH:
5593                         case STATEMENT_LABEL:
5594                         case STATEMENT_CASE_LABEL:
5595                                 last = next;
5596                                 next = next->base.next;
5597                                 break;
5598
5599                         case STATEMENT_WHILE: {
5600 continue_while:
5601                                 if (next->base.reachable)
5602                                         return;
5603                                 next->base.reachable = true;
5604
5605                                 while_statement_t const *const whiles = &next->whiles;
5606                                 int                      const val    = determine_truth(whiles->condition);
5607
5608                                 if (val >= 0)
5609                                         check_reachable(whiles->body);
5610
5611                                 if (val > 0)
5612                                         return;
5613
5614                                 last = next;
5615                                 next = next->base.next;
5616                                 break;
5617                         }
5618
5619                         case STATEMENT_DO_WHILE: {
5620 continue_do_while:
5621                                 if (next->base.reachable)
5622                                         return;
5623                                 next->base.reachable = true;
5624
5625                                 do_while_statement_t const *const dw  = &next->do_while;
5626                                 int                  const        val = determine_truth(dw->condition);
5627
5628                                 if (val >= 0)
5629                                         check_reachable(dw->body);
5630
5631                                 if (val > 0)
5632                                         return;
5633
5634                                 last = next;
5635                                 next = next->base.next;
5636                                 break;
5637                         }
5638
5639                         case STATEMENT_FOR: {
5640 continue_for:;
5641                                 for_statement_t *const fors = &next->fors;
5642
5643                                 fors->step_reachable = true;
5644
5645                                 if (fors->condition_reachable)
5646                                         return;
5647                                 fors->condition_reachable = true;
5648
5649                                 expression_t const *const cond = fors->condition;
5650                                 int          const        val  =
5651                                         cond == NULL ? 1 : determine_truth(cond);
5652
5653                                 if (val >= 0)
5654                                         check_reachable(fors->body);
5655
5656                                 if (val > 0)
5657                                         return;
5658
5659                                 last = next;
5660                                 next = next->base.next;
5661                                 break;
5662                         }
5663
5664                         case STATEMENT_MS_TRY:
5665                                 last = next;
5666                                 next = next->ms_try.final_statement;
5667                                 break;
5668                 }
5669         }
5670
5671         check_reachable(next);
5672 }
5673
5674 static void check_unreachable(statement_t* const stmt, void *const env)
5675 {
5676         (void)env;
5677
5678         switch (stmt->kind) {
5679                 case STATEMENT_DO_WHILE:
5680                         if (!stmt->base.reachable) {
5681                                 expression_t const *const cond = stmt->do_while.condition;
5682                                 if (determine_truth(cond) >= 0) {
5683                                         warningf(&cond->base.source_position,
5684                                                  "condition of do-while-loop is unreachable");
5685                                 }
5686                         }
5687                         return;
5688
5689                 case STATEMENT_FOR: {
5690                         for_statement_t const* const fors = &stmt->fors;
5691
5692                         // if init and step are unreachable, cond is unreachable, too
5693                         if (!stmt->base.reachable && !fors->step_reachable) {
5694                                 warningf(&stmt->base.source_position, "statement is unreachable");
5695                         } else {
5696                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
5697                                         warningf(&fors->initialisation->base.source_position,
5698                                                  "initialisation of for-statement is unreachable");
5699                                 }
5700
5701                                 if (!fors->condition_reachable && fors->condition != NULL) {
5702                                         warningf(&fors->condition->base.source_position,
5703                                                  "condition of for-statement is unreachable");
5704                                 }
5705
5706                                 if (!fors->step_reachable && fors->step != NULL) {
5707                                         warningf(&fors->step->base.source_position,
5708                                                  "step of for-statement is unreachable");
5709                                 }
5710                         }
5711                         return;
5712                 }
5713
5714                 case STATEMENT_COMPOUND:
5715                         if (stmt->compound.statements != NULL)
5716                                 return;
5717                         /* FALLTHROUGH*/
5718
5719                 default:
5720                         if (!stmt->base.reachable)
5721                                 warningf(&stmt->base.source_position, "statement is unreachable");
5722                         return;
5723         }
5724 }
5725
5726 static void parse_external_declaration(void)
5727 {
5728         /* function-definitions and declarations both start with declaration
5729          * specifiers */
5730         declaration_specifiers_t specifiers;
5731         memset(&specifiers, 0, sizeof(specifiers));
5732
5733         add_anchor_token(';');
5734         parse_declaration_specifiers(&specifiers);
5735         rem_anchor_token(';');
5736
5737         /* must be a declaration */
5738         if (token.type == ';') {
5739                 parse_anonymous_declaration_rest(&specifiers);
5740                 return;
5741         }
5742
5743         add_anchor_token(',');
5744         add_anchor_token('=');
5745         add_anchor_token(';');
5746         add_anchor_token('{');
5747
5748         /* declarator is common to both function-definitions and declarations */
5749         declaration_t *ndeclaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
5750
5751         rem_anchor_token('{');
5752         rem_anchor_token(';');
5753         rem_anchor_token('=');
5754         rem_anchor_token(',');
5755
5756         /* must be a declaration */
5757         switch (token.type) {
5758                 case ',':
5759                 case ';':
5760                 case '=':
5761                         parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
5762                         return;
5763         }
5764
5765         /* must be a function definition */
5766         parse_kr_declaration_list(ndeclaration);
5767
5768         if (token.type != '{') {
5769                 parse_error_expected("while parsing function definition", '{', NULL);
5770                 eat_until_matching_token(';');
5771                 return;
5772         }
5773
5774         type_t *type = ndeclaration->type;
5775
5776         /* note that we don't skip typerefs: the standard doesn't allow them here
5777          * (so we can't use is_type_function here) */
5778         if (type->kind != TYPE_FUNCTION) {
5779                 if (is_type_valid(type)) {
5780                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5781                                type, ndeclaration->symbol);
5782                 }
5783                 eat_block();
5784                 return;
5785         }
5786
5787         if (warning.aggregate_return &&
5788             is_type_compound(skip_typeref(type->function.return_type))) {
5789                 warningf(HERE, "function '%Y' returns an aggregate",
5790                          ndeclaration->symbol);
5791         }
5792         if (warning.traditional && !type->function.unspecified_parameters) {
5793                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
5794                         ndeclaration->symbol);
5795         }
5796         if (warning.old_style_definition && type->function.unspecified_parameters) {
5797                 warningf(HERE, "old-style function definition '%Y'",
5798                         ndeclaration->symbol);
5799         }
5800
5801         /* § 6.7.5.3 (14) a function definition with () means no
5802          * parameters (and not unspecified parameters) */
5803         if (type->function.unspecified_parameters
5804                         && type->function.parameters == NULL
5805                         && !type->function.kr_style_parameters) {
5806                 type_t *duplicate = duplicate_type(type);
5807                 duplicate->function.unspecified_parameters = false;
5808
5809                 type = typehash_insert(duplicate);
5810                 if (type != duplicate) {
5811                         obstack_free(type_obst, duplicate);
5812                 }
5813                 ndeclaration->type = type;
5814         }
5815
5816         declaration_t *const declaration = record_declaration(ndeclaration, true);
5817         if (ndeclaration != declaration) {
5818                 declaration->scope = ndeclaration->scope;
5819         }
5820         type = skip_typeref(declaration->type);
5821
5822         /* push function parameters and switch scope */
5823         size_t const top = environment_top();
5824         scope_push(&declaration->scope);
5825
5826         declaration_t *parameter = declaration->scope.declarations;
5827         for( ; parameter != NULL; parameter = parameter->next) {
5828                 if (parameter->parent_scope == &ndeclaration->scope) {
5829                         parameter->parent_scope = scope;
5830                 }
5831                 assert(parameter->parent_scope == NULL
5832                                 || parameter->parent_scope == scope);
5833                 parameter->parent_scope = scope;
5834                 if (parameter->symbol == NULL) {
5835                         errorf(&parameter->source_position, "parameter name omitted");
5836                         continue;
5837                 }
5838                 environment_push(parameter);
5839         }
5840
5841         if (declaration->init.statement != NULL) {
5842                 parser_error_multiple_definition(declaration, HERE);
5843                 eat_block();
5844         } else {
5845                 /* parse function body */
5846                 int            label_stack_top      = label_top();
5847                 declaration_t *old_current_function = current_function;
5848                 current_function                    = declaration;
5849                 current_parent                      = NULL;
5850
5851                 statement_t *const body = parse_compound_statement(false);
5852                 declaration->init.statement = body;
5853                 first_err = true;
5854                 check_labels();
5855                 check_declarations();
5856                 if (warning.return_type      ||
5857                     warning.unreachable_code ||
5858                     (warning.missing_noreturn && !(declaration->modifiers & DM_NORETURN))) {
5859                         noreturn_candidate = true;
5860                         check_reachable(body);
5861                         if (warning.unreachable_code)
5862                                 walk_statements(body, check_unreachable, NULL);
5863                         if (warning.missing_noreturn &&
5864                             noreturn_candidate       &&
5865                             !(declaration->modifiers & DM_NORETURN)) {
5866                                 warningf(&body->base.source_position,
5867                                          "function '%#T' is candidate for attribute 'noreturn'",
5868                                          type, declaration->symbol);
5869                         }
5870                 }
5871
5872                 assert(current_parent   == NULL);
5873                 assert(current_function == declaration);
5874                 current_function = old_current_function;
5875                 label_pop_to(label_stack_top);
5876         }
5877
5878         assert(scope == &declaration->scope);
5879         scope_pop();
5880         environment_pop_to(top);
5881 }
5882
5883 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5884                                   source_position_t *source_position,
5885                                   const symbol_t *symbol)
5886 {
5887         type_t *type = allocate_type_zero(TYPE_BITFIELD);
5888
5889         type->bitfield.base_type       = base_type;
5890         type->bitfield.size_expression = size;
5891
5892         il_size_t bit_size;
5893         type_t *skipped_type = skip_typeref(base_type);
5894         if (!is_type_integer(skipped_type)) {
5895                 errorf(HERE, "bitfield base type '%T' is not an integer type",
5896                         base_type);
5897                 bit_size = 0;
5898         } else {
5899                 bit_size = skipped_type->base.size * 8;
5900         }
5901
5902         if (is_constant_expression(size)) {
5903                 long v = fold_constant(size);
5904
5905                 if (v < 0) {
5906                         errorf(source_position, "negative width in bit-field '%Y'",
5907                                 symbol);
5908                 } else if (v == 0) {
5909                         errorf(source_position, "zero width for bit-field '%Y'",
5910                                 symbol);
5911                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
5912                         errorf(source_position, "width of '%Y' exceeds its type",
5913                                 symbol);
5914                 } else {
5915                         type->bitfield.bit_size = v;
5916                 }
5917         }
5918
5919         return type;
5920 }
5921
5922 static declaration_t *find_compound_entry(declaration_t *compound_declaration,
5923                                           symbol_t *symbol)
5924 {
5925         declaration_t *iter = compound_declaration->scope.declarations;
5926         for( ; iter != NULL; iter = iter->next) {
5927                 if (iter->namespc != NAMESPACE_NORMAL)
5928                         continue;
5929
5930                 if (iter->symbol == NULL) {
5931                         type_t *type = skip_typeref(iter->type);
5932                         if (is_type_compound(type)) {
5933                                 declaration_t *result
5934                                         = find_compound_entry(type->compound.declaration, symbol);
5935                                 if (result != NULL)
5936                                         return result;
5937                         }
5938                         continue;
5939                 }
5940
5941                 if (iter->symbol == symbol) {
5942                         return iter;
5943                 }
5944         }
5945
5946         return NULL;
5947 }
5948
5949 static void parse_compound_declarators(declaration_t *struct_declaration,
5950                 const declaration_specifiers_t *specifiers)
5951 {
5952         declaration_t *last_declaration = struct_declaration->scope.declarations;
5953         if (last_declaration != NULL) {
5954                 while (last_declaration->next != NULL) {
5955                         last_declaration = last_declaration->next;
5956                 }
5957         }
5958
5959         while (true) {
5960                 declaration_t *declaration;
5961
5962                 if (token.type == ':') {
5963                         source_position_t source_position = *HERE;
5964                         next_token();
5965
5966                         type_t *base_type = specifiers->type;
5967                         expression_t *size = parse_constant_expression();
5968
5969                         type_t *type = make_bitfield_type(base_type, size,
5970                                         &source_position, sym_anonymous);
5971
5972                         declaration                         = allocate_declaration_zero();
5973                         declaration->namespc                = NAMESPACE_NORMAL;
5974                         declaration->declared_storage_class = STORAGE_CLASS_NONE;
5975                         declaration->storage_class          = STORAGE_CLASS_NONE;
5976                         declaration->source_position        = source_position;
5977                         declaration->modifiers              = specifiers->modifiers;
5978                         declaration->type                   = type;
5979                 } else {
5980                         declaration = parse_declarator(specifiers,/*may_be_abstract=*/true);
5981
5982                         type_t *orig_type = declaration->type;
5983                         type_t *type      = skip_typeref(orig_type);
5984
5985                         if (token.type == ':') {
5986                                 source_position_t source_position = *HERE;
5987                                 next_token();
5988                                 expression_t *size = parse_constant_expression();
5989
5990                                 type_t *bitfield_type = make_bitfield_type(orig_type, size,
5991                                                 &source_position, declaration->symbol);
5992                                 declaration->type = bitfield_type;
5993                         } else {
5994                                 /* TODO we ignore arrays for now... what is missing is a check
5995                                  * that they're at the end of the struct */
5996                                 if (is_type_incomplete(type) && !is_type_array(type)) {
5997                                         errorf(HERE,
5998                                                "compound member '%Y' has incomplete type '%T'",
5999                                                declaration->symbol, orig_type);
6000                                 } else if (is_type_function(type)) {
6001                                         errorf(HERE, "compound member '%Y' must not have function type '%T'",
6002                                                declaration->symbol, orig_type);
6003                                 }
6004                         }
6005                 }
6006
6007                 /* make sure we don't define a symbol multiple times */
6008                 symbol_t *symbol = declaration->symbol;
6009                 if (symbol != NULL) {
6010                         declaration_t *prev_decl
6011                                 = find_compound_entry(struct_declaration, symbol);
6012
6013                         if (prev_decl != NULL) {
6014                                 assert(prev_decl->symbol == symbol);
6015                                 errorf(&declaration->source_position,
6016                                        "multiple declarations of symbol '%Y' (declared %P)",
6017                                        symbol, &prev_decl->source_position);
6018                         }
6019                 }
6020
6021                 /* append declaration */
6022                 if (last_declaration != NULL) {
6023                         last_declaration->next = declaration;
6024                 } else {
6025                         struct_declaration->scope.declarations = declaration;
6026                 }
6027                 last_declaration = declaration;
6028
6029                 if (token.type != ',')
6030                         break;
6031                 next_token();
6032         }
6033         expect(';');
6034
6035 end_error:
6036         ;
6037 }
6038
6039 static void parse_compound_type_entries(declaration_t *compound_declaration)
6040 {
6041         eat('{');
6042         add_anchor_token('}');
6043
6044         while (token.type != '}') {
6045                 if (token.type == T_EOF) {
6046                         errorf(HERE, "EOF while parsing struct");
6047                         break;
6048                 }
6049                 declaration_specifiers_t specifiers;
6050                 memset(&specifiers, 0, sizeof(specifiers));
6051                 parse_declaration_specifiers(&specifiers);
6052
6053                 parse_compound_declarators(compound_declaration, &specifiers);
6054         }
6055         rem_anchor_token('}');
6056         next_token();
6057 }
6058
6059 static type_t *parse_typename(void)
6060 {
6061         declaration_specifiers_t specifiers;
6062         memset(&specifiers, 0, sizeof(specifiers));
6063         parse_declaration_specifiers(&specifiers);
6064         if (specifiers.declared_storage_class != STORAGE_CLASS_NONE) {
6065                 /* TODO: improve error message, user does probably not know what a
6066                  * storage class is...
6067                  */
6068                 errorf(HERE, "typename may not have a storage class");
6069         }
6070
6071         type_t *result = parse_abstract_declarator(specifiers.type);
6072
6073         return result;
6074 }
6075
6076
6077
6078
6079 typedef expression_t* (*parse_expression_function)(void);
6080 typedef expression_t* (*parse_expression_infix_function)(expression_t *left);
6081
6082 typedef struct expression_parser_function_t expression_parser_function_t;
6083 struct expression_parser_function_t {
6084         parse_expression_function        parser;
6085         unsigned                         infix_precedence;
6086         parse_expression_infix_function  infix_parser;
6087 };
6088
6089 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
6090
6091 /**
6092  * Prints an error message if an expression was expected but not read
6093  */
6094 static expression_t *expected_expression_error(void)
6095 {
6096         /* skip the error message if the error token was read */
6097         if (token.type != T_ERROR) {
6098                 errorf(HERE, "expected expression, got token '%K'", &token);
6099         }
6100         next_token();
6101
6102         return create_invalid_expression();
6103 }
6104
6105 /**
6106  * Parse a string constant.
6107  */
6108 static expression_t *parse_string_const(void)
6109 {
6110         wide_string_t wres;
6111         if (token.type == T_STRING_LITERAL) {
6112                 string_t res = token.v.string;
6113                 next_token();
6114                 while (token.type == T_STRING_LITERAL) {
6115                         res = concat_strings(&res, &token.v.string);
6116                         next_token();
6117                 }
6118                 if (token.type != T_WIDE_STRING_LITERAL) {
6119                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
6120                         /* note: that we use type_char_ptr here, which is already the
6121                          * automatic converted type. revert_automatic_type_conversion
6122                          * will construct the array type */
6123                         cnst->base.type    = warning.write_strings ? type_const_char_ptr : type_char_ptr;
6124                         cnst->string.value = res;
6125                         return cnst;
6126                 }
6127
6128                 wres = concat_string_wide_string(&res, &token.v.wide_string);
6129         } else {
6130                 wres = token.v.wide_string;
6131         }
6132         next_token();
6133
6134         for (;;) {
6135                 switch (token.type) {
6136                         case T_WIDE_STRING_LITERAL:
6137                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
6138                                 break;
6139
6140                         case T_STRING_LITERAL:
6141                                 wres = concat_wide_string_string(&wres, &token.v.string);
6142                                 break;
6143
6144                         default: {
6145                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
6146                                 cnst->base.type         = warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
6147                                 cnst->wide_string.value = wres;
6148                                 return cnst;
6149                         }
6150                 }
6151                 next_token();
6152         }
6153 }
6154
6155 /**
6156  * Parse an integer constant.
6157  */
6158 static expression_t *parse_int_const(void)
6159 {
6160         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6161         cnst->base.source_position = *HERE;
6162         cnst->base.type            = token.datatype;
6163         cnst->conste.v.int_value   = token.v.intvalue;
6164
6165         next_token();
6166
6167         return cnst;
6168 }
6169
6170 /**
6171  * Parse a character constant.
6172  */
6173 static expression_t *parse_character_constant(void)
6174 {
6175         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
6176
6177         cnst->base.source_position = *HERE;
6178         cnst->base.type            = token.datatype;
6179         cnst->conste.v.character   = token.v.string;
6180
6181         if (cnst->conste.v.character.size != 1) {
6182                 if (warning.multichar && GNU_MODE) {
6183                         warningf(HERE, "multi-character character constant");
6184                 } else {
6185                         errorf(HERE, "more than 1 characters in character constant");
6186                 }
6187         }
6188         next_token();
6189
6190         return cnst;
6191 }
6192
6193 /**
6194  * Parse a wide character constant.
6195  */
6196 static expression_t *parse_wide_character_constant(void)
6197 {
6198         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
6199
6200         cnst->base.source_position    = *HERE;
6201         cnst->base.type               = token.datatype;
6202         cnst->conste.v.wide_character = token.v.wide_string;
6203
6204         if (cnst->conste.v.wide_character.size != 1) {
6205                 if (warning.multichar && GNU_MODE) {
6206                         warningf(HERE, "multi-character character constant");
6207                 } else {
6208                         errorf(HERE, "more than 1 characters in character constant");
6209                 }
6210         }
6211         next_token();
6212
6213         return cnst;
6214 }
6215
6216 /**
6217  * Parse a float constant.
6218  */
6219 static expression_t *parse_float_const(void)
6220 {
6221         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6222         cnst->base.type            = token.datatype;
6223         cnst->conste.v.float_value = token.v.floatvalue;
6224
6225         next_token();
6226
6227         return cnst;
6228 }
6229
6230 static declaration_t *create_implicit_function(symbol_t *symbol,
6231                 const source_position_t *source_position)
6232 {
6233         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION);
6234         ntype->function.return_type            = type_int;
6235         ntype->function.unspecified_parameters = true;
6236
6237         type_t *type = typehash_insert(ntype);
6238         if (type != ntype) {
6239                 free_type(ntype);
6240         }
6241
6242         declaration_t *const declaration    = allocate_declaration_zero();
6243         declaration->storage_class          = STORAGE_CLASS_EXTERN;
6244         declaration->declared_storage_class = STORAGE_CLASS_EXTERN;
6245         declaration->type                   = type;
6246         declaration->symbol                 = symbol;
6247         declaration->source_position        = *source_position;
6248         declaration->implicit               = true;
6249
6250         bool strict_prototypes_old = warning.strict_prototypes;
6251         warning.strict_prototypes  = false;
6252         record_declaration(declaration, false);
6253         warning.strict_prototypes = strict_prototypes_old;
6254
6255         return declaration;
6256 }
6257
6258 /**
6259  * Creates a return_type (func)(argument_type) function type if not
6260  * already exists.
6261  */
6262 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
6263                                     type_t *argument_type2)
6264 {
6265         function_parameter_t *parameter2
6266                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
6267         memset(parameter2, 0, sizeof(parameter2[0]));
6268         parameter2->type = argument_type2;
6269
6270         function_parameter_t *parameter1
6271                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
6272         memset(parameter1, 0, sizeof(parameter1[0]));
6273         parameter1->type = argument_type1;
6274         parameter1->next = parameter2;
6275
6276         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6277         type->function.return_type = return_type;
6278         type->function.parameters  = parameter1;
6279
6280         type_t *result = typehash_insert(type);
6281         if (result != type) {
6282                 free_type(type);
6283         }
6284
6285         return result;
6286 }
6287
6288 /**
6289  * Creates a return_type (func)(argument_type) function type if not
6290  * already exists.
6291  *
6292  * @param return_type    the return type
6293  * @param argument_type  the argument type
6294  */
6295 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
6296 {
6297         function_parameter_t *parameter
6298                 = obstack_alloc(type_obst, sizeof(parameter[0]));
6299         memset(parameter, 0, sizeof(parameter[0]));
6300         parameter->type = argument_type;
6301
6302         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6303         type->function.return_type = return_type;
6304         type->function.parameters  = parameter;
6305
6306         type_t *result = typehash_insert(type);
6307         if (result != type) {
6308                 free_type(type);
6309         }
6310
6311         return result;
6312 }
6313
6314 static type_t *make_function_0_type(type_t *return_type)
6315 {
6316         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6317         type->function.return_type = return_type;
6318         type->function.parameters  = NULL;
6319
6320         type_t *result = typehash_insert(type);
6321         if (result != type) {
6322                 free_type(type);
6323         }
6324
6325         return result;
6326 }
6327
6328 /**
6329  * Creates a function type for some function like builtins.
6330  *
6331  * @param symbol   the symbol describing the builtin
6332  */
6333 static type_t *get_builtin_symbol_type(symbol_t *symbol)
6334 {
6335         switch(symbol->ID) {
6336         case T___builtin_alloca:
6337                 return make_function_1_type(type_void_ptr, type_size_t);
6338         case T___builtin_huge_val:
6339                 return make_function_0_type(type_double);
6340         case T___builtin_inf:
6341                 return make_function_0_type(type_double);
6342         case T___builtin_inff:
6343                 return make_function_0_type(type_float);
6344         case T___builtin_infl:
6345                 return make_function_0_type(type_long_double);
6346         case T___builtin_nan:
6347                 return make_function_1_type(type_double, type_char_ptr);
6348         case T___builtin_nanf:
6349                 return make_function_1_type(type_float, type_char_ptr);
6350         case T___builtin_nanl:
6351                 return make_function_1_type(type_long_double, type_char_ptr);
6352         case T___builtin_va_end:
6353                 return make_function_1_type(type_void, type_valist);
6354         case T___builtin_expect:
6355                 return make_function_2_type(type_long, type_long, type_long);
6356         default:
6357                 internal_errorf(HERE, "not implemented builtin symbol found");
6358         }
6359 }
6360
6361 /**
6362  * Performs automatic type cast as described in § 6.3.2.1.
6363  *
6364  * @param orig_type  the original type
6365  */
6366 static type_t *automatic_type_conversion(type_t *orig_type)
6367 {
6368         type_t *type = skip_typeref(orig_type);
6369         if (is_type_array(type)) {
6370                 array_type_t *array_type   = &type->array;
6371                 type_t       *element_type = array_type->element_type;
6372                 unsigned      qualifiers   = array_type->base.qualifiers;
6373
6374                 return make_pointer_type(element_type, qualifiers);
6375         }
6376
6377         if (is_type_function(type)) {
6378                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6379         }
6380
6381         return orig_type;
6382 }
6383
6384 /**
6385  * reverts the automatic casts of array to pointer types and function
6386  * to function-pointer types as defined § 6.3.2.1
6387  */
6388 type_t *revert_automatic_type_conversion(const expression_t *expression)
6389 {
6390         switch (expression->kind) {
6391                 case EXPR_REFERENCE: return expression->reference.declaration->type;
6392
6393                 case EXPR_SELECT:
6394                         return get_qualified_type(expression->select.compound_entry->type,
6395                                                   expression->base.type->base.qualifiers);
6396
6397                 case EXPR_UNARY_DEREFERENCE: {
6398                         const expression_t *const value = expression->unary.value;
6399                         type_t             *const type  = skip_typeref(value->base.type);
6400                         assert(is_type_pointer(type));
6401                         return type->pointer.points_to;
6402                 }
6403
6404                 case EXPR_BUILTIN_SYMBOL:
6405                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
6406
6407                 case EXPR_ARRAY_ACCESS: {
6408                         const expression_t *array_ref = expression->array_access.array_ref;
6409                         type_t             *type_left = skip_typeref(array_ref->base.type);
6410                         if (!is_type_valid(type_left))
6411                                 return type_left;
6412                         assert(is_type_pointer(type_left));
6413                         return type_left->pointer.points_to;
6414                 }
6415
6416                 case EXPR_STRING_LITERAL: {
6417                         size_t size = expression->string.value.size;
6418                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
6419                 }
6420
6421                 case EXPR_WIDE_STRING_LITERAL: {
6422                         size_t size = expression->wide_string.value.size;
6423                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
6424                 }
6425
6426                 case EXPR_COMPOUND_LITERAL:
6427                         return expression->compound_literal.type;
6428
6429                 default: break;
6430         }
6431
6432         return expression->base.type;
6433 }
6434
6435 static expression_t *parse_reference(void)
6436 {
6437         expression_t *expression = allocate_expression_zero(EXPR_REFERENCE);
6438
6439         reference_expression_t *ref = &expression->reference;
6440         symbol_t *const symbol = token.v.symbol;
6441
6442         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
6443
6444         if (declaration == NULL) {
6445                 if (!strict_mode && look_ahead(1)->type == '(') {
6446                         /* an implicitly declared function */
6447                         if (warning.implicit_function_declaration) {
6448                                 warningf(HERE, "implicit declaration of function '%Y'",
6449                                         symbol);
6450                         }
6451
6452                         declaration = create_implicit_function(symbol, HERE);
6453                 } else {
6454                         errorf(HERE, "unknown symbol '%Y' found.", symbol);
6455                         declaration = create_error_declaration(symbol, STORAGE_CLASS_NONE);
6456                 }
6457         }
6458
6459         type_t *orig_type = declaration->type;
6460
6461         /* we always do the auto-type conversions; the & and sizeof parser contains
6462          * code to revert this! */
6463         type_t *type = automatic_type_conversion(orig_type);
6464
6465         ref->declaration = declaration;
6466         ref->base.type   = type;
6467
6468         /* this declaration is used */
6469         declaration->used = true;
6470
6471         if (declaration->parent_scope != file_scope                          &&
6472             declaration->parent_scope->depth < current_function->scope.depth &&
6473             is_type_valid(orig_type) && !is_type_function(orig_type)) {
6474                 /* access of a variable from an outer function */
6475                 declaration->address_taken     = true;
6476                 current_function->need_closure = true;
6477         }
6478
6479         /* check for deprecated functions */
6480         if (warning.deprecated_declarations &&
6481             declaration->modifiers & DM_DEPRECATED) {
6482                 char const *const prefix = is_type_function(declaration->type) ?
6483                         "function" : "variable";
6484
6485                 if (declaration->deprecated_string != NULL) {
6486                         warningf(HERE, "%s '%Y' is deprecated (declared %P): \"%s\"",
6487                                 prefix, declaration->symbol, &declaration->source_position,
6488                                 declaration->deprecated_string);
6489                 } else {
6490                         warningf(HERE, "%s '%Y' is deprecated (declared %P)", prefix,
6491                                 declaration->symbol, &declaration->source_position);
6492                 }
6493         }
6494         if (warning.init_self && declaration == current_init_decl && !in_type_prop) {
6495                 current_init_decl = NULL;
6496                 warningf(HERE, "variable '%#T' is initialized by itself",
6497                         declaration->type, declaration->symbol);
6498         }
6499
6500         next_token();
6501         return expression;
6502 }
6503
6504 static bool semantic_cast(expression_t *cast)
6505 {
6506         expression_t            *expression      = cast->unary.value;
6507         type_t                  *orig_dest_type  = cast->base.type;
6508         type_t                  *orig_type_right = expression->base.type;
6509         type_t            const *dst_type        = skip_typeref(orig_dest_type);
6510         type_t            const *src_type        = skip_typeref(orig_type_right);
6511         source_position_t const *pos             = &cast->base.source_position;
6512
6513         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
6514         if (dst_type == type_void)
6515                 return true;
6516
6517         /* only integer and pointer can be casted to pointer */
6518         if (is_type_pointer(dst_type)  &&
6519             !is_type_pointer(src_type) &&
6520             !is_type_integer(src_type) &&
6521             is_type_valid(src_type)) {
6522                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
6523                 return false;
6524         }
6525
6526         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
6527                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
6528                 return false;
6529         }
6530
6531         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
6532                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
6533                 return false;
6534         }
6535
6536         if (warning.cast_qual &&
6537             is_type_pointer(src_type) &&
6538             is_type_pointer(dst_type)) {
6539                 type_t *src = skip_typeref(src_type->pointer.points_to);
6540                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
6541                 unsigned missing_qualifiers =
6542                         src->base.qualifiers & ~dst->base.qualifiers;
6543                 if (missing_qualifiers != 0) {
6544                         warningf(pos,
6545                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
6546                                  missing_qualifiers, orig_type_right);
6547                 }
6548         }
6549         return true;
6550 }
6551
6552 static expression_t *parse_compound_literal(type_t *type)
6553 {
6554         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
6555
6556         parse_initializer_env_t env;
6557         env.type             = type;
6558         env.declaration      = NULL;
6559         env.must_be_constant = false;
6560         initializer_t *initializer = parse_initializer(&env);
6561         type = env.type;
6562
6563         expression->compound_literal.initializer = initializer;
6564         expression->compound_literal.type        = type;
6565         expression->base.type                    = automatic_type_conversion(type);
6566
6567         return expression;
6568 }
6569
6570 /**
6571  * Parse a cast expression.
6572  */
6573 static expression_t *parse_cast(void)
6574 {
6575         add_anchor_token(')');
6576
6577         source_position_t source_position = token.source_position;
6578
6579         type_t *type  = parse_typename();
6580
6581         rem_anchor_token(')');
6582         expect(')');
6583
6584         if (token.type == '{') {
6585                 return parse_compound_literal(type);
6586         }
6587
6588         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
6589         cast->base.source_position = source_position;
6590
6591         expression_t *value = parse_sub_expression(PREC_CAST);
6592         cast->base.type   = type;
6593         cast->unary.value = value;
6594
6595         if (! semantic_cast(cast)) {
6596                 /* TODO: record the error in the AST. else it is impossible to detect it */
6597         }
6598
6599         return cast;
6600 end_error:
6601         return create_invalid_expression();
6602 }
6603
6604 /**
6605  * Parse a statement expression.
6606  */
6607 static expression_t *parse_statement_expression(void)
6608 {
6609         add_anchor_token(')');
6610
6611         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
6612
6613         statement_t *statement           = parse_compound_statement(true);
6614         expression->statement.statement  = statement;
6615         expression->base.source_position = statement->base.source_position;
6616
6617         /* find last statement and use its type */
6618         type_t *type = type_void;
6619         const statement_t *stmt = statement->compound.statements;
6620         if (stmt != NULL) {
6621                 while (stmt->base.next != NULL)
6622                         stmt = stmt->base.next;
6623
6624                 if (stmt->kind == STATEMENT_EXPRESSION) {
6625                         type = stmt->expression.expression->base.type;
6626                 }
6627         } else if (warning.other) {
6628                 warningf(&expression->base.source_position, "empty statement expression ({})");
6629         }
6630         expression->base.type = type;
6631
6632         rem_anchor_token(')');
6633         expect(')');
6634
6635 end_error:
6636         return expression;
6637 }
6638
6639 /**
6640  * Parse a parenthesized expression.
6641  */
6642 static expression_t *parse_parenthesized_expression(void)
6643 {
6644         eat('(');
6645
6646         switch(token.type) {
6647         case '{':
6648                 /* gcc extension: a statement expression */
6649                 return parse_statement_expression();
6650
6651         TYPE_QUALIFIERS
6652         TYPE_SPECIFIERS
6653                 return parse_cast();
6654         case T_IDENTIFIER:
6655                 if (is_typedef_symbol(token.v.symbol)) {
6656                         return parse_cast();
6657                 }
6658         }
6659
6660         add_anchor_token(')');
6661         expression_t *result = parse_expression();
6662         rem_anchor_token(')');
6663         expect(')');
6664
6665 end_error:
6666         return result;
6667 }
6668
6669 static expression_t *parse_function_keyword(void)
6670 {
6671         next_token();
6672         /* TODO */
6673
6674         if (current_function == NULL) {
6675                 errorf(HERE, "'__func__' used outside of a function");
6676         }
6677
6678         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6679         expression->base.type     = type_char_ptr;
6680         expression->funcname.kind = FUNCNAME_FUNCTION;
6681
6682         return expression;
6683 }
6684
6685 static expression_t *parse_pretty_function_keyword(void)
6686 {
6687         eat(T___PRETTY_FUNCTION__);
6688
6689         if (current_function == NULL) {
6690                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
6691         }
6692
6693         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6694         expression->base.type     = type_char_ptr;
6695         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
6696
6697         return expression;
6698 }
6699
6700 static expression_t *parse_funcsig_keyword(void)
6701 {
6702         eat(T___FUNCSIG__);
6703
6704         if (current_function == NULL) {
6705                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
6706         }
6707
6708         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6709         expression->base.type     = type_char_ptr;
6710         expression->funcname.kind = FUNCNAME_FUNCSIG;
6711
6712         return expression;
6713 }
6714
6715 static expression_t *parse_funcdname_keyword(void)
6716 {
6717         eat(T___FUNCDNAME__);
6718
6719         if (current_function == NULL) {
6720                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
6721         }
6722
6723         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6724         expression->base.type     = type_char_ptr;
6725         expression->funcname.kind = FUNCNAME_FUNCDNAME;
6726
6727         return expression;
6728 }
6729
6730 static designator_t *parse_designator(void)
6731 {
6732         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
6733         result->source_position = *HERE;
6734
6735         if (token.type != T_IDENTIFIER) {
6736                 parse_error_expected("while parsing member designator",
6737                                      T_IDENTIFIER, NULL);
6738                 return NULL;
6739         }
6740         result->symbol = token.v.symbol;
6741         next_token();
6742
6743         designator_t *last_designator = result;
6744         while(true) {
6745                 if (token.type == '.') {
6746                         next_token();
6747                         if (token.type != T_IDENTIFIER) {
6748                                 parse_error_expected("while parsing member designator",
6749                                                      T_IDENTIFIER, NULL);
6750                                 return NULL;
6751                         }
6752                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6753                         designator->source_position = *HERE;
6754                         designator->symbol          = token.v.symbol;
6755                         next_token();
6756
6757                         last_designator->next = designator;
6758                         last_designator       = designator;
6759                         continue;
6760                 }
6761                 if (token.type == '[') {
6762                         next_token();
6763                         add_anchor_token(']');
6764                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6765                         designator->source_position = *HERE;
6766                         designator->array_index     = parse_expression();
6767                         rem_anchor_token(']');
6768                         expect(']');
6769                         if (designator->array_index == NULL) {
6770                                 return NULL;
6771                         }
6772
6773                         last_designator->next = designator;
6774                         last_designator       = designator;
6775                         continue;
6776                 }
6777                 break;
6778         }
6779
6780         return result;
6781 end_error:
6782         return NULL;
6783 }
6784
6785 /**
6786  * Parse the __builtin_offsetof() expression.
6787  */
6788 static expression_t *parse_offsetof(void)
6789 {
6790         eat(T___builtin_offsetof);
6791
6792         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6793         expression->base.type    = type_size_t;
6794
6795         expect('(');
6796         add_anchor_token(',');
6797         type_t *type = parse_typename();
6798         rem_anchor_token(',');
6799         expect(',');
6800         add_anchor_token(')');
6801         designator_t *designator = parse_designator();
6802         rem_anchor_token(')');
6803         expect(')');
6804
6805         expression->offsetofe.type       = type;
6806         expression->offsetofe.designator = designator;
6807
6808         type_path_t path;
6809         memset(&path, 0, sizeof(path));
6810         path.top_type = type;
6811         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6812
6813         descend_into_subtype(&path);
6814
6815         if (!walk_designator(&path, designator, true)) {
6816                 return create_invalid_expression();
6817         }
6818
6819         DEL_ARR_F(path.path);
6820
6821         return expression;
6822 end_error:
6823         return create_invalid_expression();
6824 }
6825
6826 /**
6827  * Parses a _builtin_va_start() expression.
6828  */
6829 static expression_t *parse_va_start(void)
6830 {
6831         eat(T___builtin_va_start);
6832
6833         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6834
6835         expect('(');
6836         add_anchor_token(',');
6837         expression->va_starte.ap = parse_assignment_expression();
6838         rem_anchor_token(',');
6839         expect(',');
6840         expression_t *const expr = parse_assignment_expression();
6841         if (expr->kind == EXPR_REFERENCE) {
6842                 declaration_t *const decl = expr->reference.declaration;
6843                 if (decl->parent_scope != &current_function->scope || decl->next != NULL) {
6844                         errorf(&expr->base.source_position,
6845                                "second argument of 'va_start' must be last parameter of the current function");
6846                 }
6847                 expression->va_starte.parameter = decl;
6848                 expect(')');
6849                 return expression;
6850         }
6851         expect(')');
6852 end_error:
6853         return create_invalid_expression();
6854 }
6855
6856 /**
6857  * Parses a _builtin_va_arg() expression.
6858  */
6859 static expression_t *parse_va_arg(void)
6860 {
6861         eat(T___builtin_va_arg);
6862
6863         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6864
6865         expect('(');
6866         expression->va_arge.ap = parse_assignment_expression();
6867         expect(',');
6868         expression->base.type = parse_typename();
6869         expect(')');
6870
6871         return expression;
6872 end_error:
6873         return create_invalid_expression();
6874 }
6875
6876 static expression_t *parse_builtin_symbol(void)
6877 {
6878         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
6879
6880         symbol_t *symbol = token.v.symbol;
6881
6882         expression->builtin_symbol.symbol = symbol;
6883         next_token();
6884
6885         type_t *type = get_builtin_symbol_type(symbol);
6886         type = automatic_type_conversion(type);
6887
6888         expression->base.type = type;
6889         return expression;
6890 }
6891
6892 /**
6893  * Parses a __builtin_constant() expression.
6894  */
6895 static expression_t *parse_builtin_constant(void)
6896 {
6897         eat(T___builtin_constant_p);
6898
6899         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6900
6901         expect('(');
6902         add_anchor_token(')');
6903         expression->builtin_constant.value = parse_assignment_expression();
6904         rem_anchor_token(')');
6905         expect(')');
6906         expression->base.type = type_int;
6907
6908         return expression;
6909 end_error:
6910         return create_invalid_expression();
6911 }
6912
6913 /**
6914  * Parses a __builtin_prefetch() expression.
6915  */
6916 static expression_t *parse_builtin_prefetch(void)
6917 {
6918         eat(T___builtin_prefetch);
6919
6920         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
6921
6922         expect('(');
6923         add_anchor_token(')');
6924         expression->builtin_prefetch.adr = parse_assignment_expression();
6925         if (token.type == ',') {
6926                 next_token();
6927                 expression->builtin_prefetch.rw = parse_assignment_expression();
6928         }
6929         if (token.type == ',') {
6930                 next_token();
6931                 expression->builtin_prefetch.locality = parse_assignment_expression();
6932         }
6933         rem_anchor_token(')');
6934         expect(')');
6935         expression->base.type = type_void;
6936
6937         return expression;
6938 end_error:
6939         return create_invalid_expression();
6940 }
6941
6942 /**
6943  * Parses a __builtin_is_*() compare expression.
6944  */
6945 static expression_t *parse_compare_builtin(void)
6946 {
6947         expression_t *expression;
6948
6949         switch(token.type) {
6950         case T___builtin_isgreater:
6951                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6952                 break;
6953         case T___builtin_isgreaterequal:
6954                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6955                 break;
6956         case T___builtin_isless:
6957                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6958                 break;
6959         case T___builtin_islessequal:
6960                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6961                 break;
6962         case T___builtin_islessgreater:
6963                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6964                 break;
6965         case T___builtin_isunordered:
6966                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6967                 break;
6968         default:
6969                 internal_errorf(HERE, "invalid compare builtin found");
6970         }
6971         expression->base.source_position = *HERE;
6972         next_token();
6973
6974         expect('(');
6975         expression->binary.left = parse_assignment_expression();
6976         expect(',');
6977         expression->binary.right = parse_assignment_expression();
6978         expect(')');
6979
6980         type_t *const orig_type_left  = expression->binary.left->base.type;
6981         type_t *const orig_type_right = expression->binary.right->base.type;
6982
6983         type_t *const type_left  = skip_typeref(orig_type_left);
6984         type_t *const type_right = skip_typeref(orig_type_right);
6985         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6986                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6987                         type_error_incompatible("invalid operands in comparison",
6988                                 &expression->base.source_position, orig_type_left, orig_type_right);
6989                 }
6990         } else {
6991                 semantic_comparison(&expression->binary);
6992         }
6993
6994         return expression;
6995 end_error:
6996         return create_invalid_expression();
6997 }
6998
6999 #if 0
7000 /**
7001  * Parses a __builtin_expect() expression.
7002  */
7003 static expression_t *parse_builtin_expect(void)
7004 {
7005         eat(T___builtin_expect);
7006
7007         expression_t *expression
7008                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
7009
7010         expect('(');
7011         expression->binary.left = parse_assignment_expression();
7012         expect(',');
7013         expression->binary.right = parse_constant_expression();
7014         expect(')');
7015
7016         expression->base.type = expression->binary.left->base.type;
7017
7018         return expression;
7019 end_error:
7020         return create_invalid_expression();
7021 }
7022 #endif
7023
7024 /**
7025  * Parses a MS assume() expression.
7026  */
7027 static expression_t *parse_assume(void)
7028 {
7029         eat(T__assume);
7030
7031         expression_t *expression
7032                 = allocate_expression_zero(EXPR_UNARY_ASSUME);
7033
7034         expect('(');
7035         add_anchor_token(')');
7036         expression->unary.value = parse_assignment_expression();
7037         rem_anchor_token(')');
7038         expect(')');
7039
7040         expression->base.type = type_void;
7041         return expression;
7042 end_error:
7043         return create_invalid_expression();
7044 }
7045
7046 /**
7047  * Return the declaration for a given label symbol or create a new one.
7048  *
7049  * @param symbol  the symbol of the label
7050  */
7051 static declaration_t *get_label(symbol_t *symbol)
7052 {
7053         declaration_t *candidate;
7054         assert(current_function != NULL);
7055
7056         candidate = get_declaration(symbol, NAMESPACE_LOCAL_LABEL);
7057         /* if we found a local label, we already created the declaration */
7058         if (candidate != NULL) {
7059                 if (candidate->parent_scope != scope) {
7060                         assert(candidate->parent_scope->depth < scope->depth);
7061                         current_function->goto_to_outer = true;
7062                 }
7063                 return candidate;
7064         }
7065
7066         candidate = get_declaration(symbol, NAMESPACE_LABEL);
7067         /* if we found a label in the same function, then we already created the
7068          * declaration */
7069         if (candidate != NULL
7070                         && candidate->parent_scope == &current_function->scope) {
7071                 return candidate;
7072         }
7073
7074         /* otherwise we need to create a new one */
7075         declaration_t *const declaration = allocate_declaration_zero();
7076         declaration->namespc       = NAMESPACE_LABEL;
7077         declaration->symbol        = symbol;
7078
7079         label_push(declaration);
7080
7081         return declaration;
7082 }
7083
7084 /**
7085  * Parses a GNU && label address expression.
7086  */
7087 static expression_t *parse_label_address(void)
7088 {
7089         source_position_t source_position = token.source_position;
7090         eat(T_ANDAND);
7091         if (token.type != T_IDENTIFIER) {
7092                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
7093                 goto end_error;
7094         }
7095         symbol_t *symbol = token.v.symbol;
7096         next_token();
7097
7098         declaration_t *label = get_label(symbol);
7099
7100         label->used          = true;
7101         label->address_taken = true;
7102
7103         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
7104         expression->base.source_position = source_position;
7105
7106         /* label address is threaten as a void pointer */
7107         expression->base.type                 = type_void_ptr;
7108         expression->label_address.declaration = label;
7109         return expression;
7110 end_error:
7111         return create_invalid_expression();
7112 }
7113
7114 /**
7115  * Parse a microsoft __noop expression.
7116  */
7117 static expression_t *parse_noop_expression(void)
7118 {
7119         source_position_t source_position = *HERE;
7120         eat(T___noop);
7121
7122         if (token.type == '(') {
7123                 /* parse arguments */
7124                 eat('(');
7125                 add_anchor_token(')');
7126                 add_anchor_token(',');
7127
7128                 if (token.type != ')') {
7129                         while(true) {
7130                                 (void)parse_assignment_expression();
7131                                 if (token.type != ',')
7132                                         break;
7133                                 next_token();
7134                         }
7135                 }
7136         }
7137         rem_anchor_token(',');
7138         rem_anchor_token(')');
7139         expect(')');
7140
7141         /* the result is a (int)0 */
7142         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
7143         cnst->base.source_position = source_position;
7144         cnst->base.type            = type_int;
7145         cnst->conste.v.int_value   = 0;
7146         cnst->conste.is_ms_noop    = true;
7147
7148         return cnst;
7149
7150 end_error:
7151         return create_invalid_expression();
7152 }
7153
7154 /**
7155  * Parses a primary expression.
7156  */
7157 static expression_t *parse_primary_expression(void)
7158 {
7159         switch (token.type) {
7160                 case T_INTEGER:                  return parse_int_const();
7161                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
7162                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
7163                 case T_FLOATINGPOINT:            return parse_float_const();
7164                 case T_STRING_LITERAL:
7165                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
7166                 case T_IDENTIFIER:               return parse_reference();
7167                 case T___FUNCTION__:
7168                 case T___func__:                 return parse_function_keyword();
7169                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
7170                 case T___FUNCSIG__:              return parse_funcsig_keyword();
7171                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
7172                 case T___builtin_offsetof:       return parse_offsetof();
7173                 case T___builtin_va_start:       return parse_va_start();
7174                 case T___builtin_va_arg:         return parse_va_arg();
7175                 case T___builtin_expect:
7176                 case T___builtin_alloca:
7177                 case T___builtin_inf:
7178                 case T___builtin_inff:
7179                 case T___builtin_infl:
7180                 case T___builtin_nan:
7181                 case T___builtin_nanf:
7182                 case T___builtin_nanl:
7183                 case T___builtin_huge_val:
7184                 case T___builtin_va_end:         return parse_builtin_symbol();
7185                 case T___builtin_isgreater:
7186                 case T___builtin_isgreaterequal:
7187                 case T___builtin_isless:
7188                 case T___builtin_islessequal:
7189                 case T___builtin_islessgreater:
7190                 case T___builtin_isunordered:    return parse_compare_builtin();
7191                 case T___builtin_constant_p:     return parse_builtin_constant();
7192                 case T___builtin_prefetch:       return parse_builtin_prefetch();
7193                 case T__assume:                  return parse_assume();
7194                 case T_ANDAND:
7195                         if (GNU_MODE)
7196                                 return parse_label_address();
7197                         break;
7198
7199                 case '(':                        return parse_parenthesized_expression();
7200                 case T___noop:                   return parse_noop_expression();
7201         }
7202
7203         errorf(HERE, "unexpected token %K, expected an expression", &token);
7204         return create_invalid_expression();
7205 }
7206
7207 /**
7208  * Check if the expression has the character type and issue a warning then.
7209  */
7210 static void check_for_char_index_type(const expression_t *expression)
7211 {
7212         type_t       *const type      = expression->base.type;
7213         const type_t *const base_type = skip_typeref(type);
7214
7215         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
7216                         warning.char_subscripts) {
7217                 warningf(&expression->base.source_position,
7218                          "array subscript has type '%T'", type);
7219         }
7220 }
7221
7222 static expression_t *parse_array_expression(expression_t *left)
7223 {
7224         eat('[');
7225         add_anchor_token(']');
7226
7227         expression_t *inside = parse_expression();
7228
7229         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
7230
7231         array_access_expression_t *array_access = &expression->array_access;
7232
7233         type_t *const orig_type_left   = left->base.type;
7234         type_t *const orig_type_inside = inside->base.type;
7235
7236         type_t *const type_left   = skip_typeref(orig_type_left);
7237         type_t *const type_inside = skip_typeref(orig_type_inside);
7238
7239         type_t *return_type;
7240         if (is_type_pointer(type_left)) {
7241                 return_type             = type_left->pointer.points_to;
7242                 array_access->array_ref = left;
7243                 array_access->index     = inside;
7244                 check_for_char_index_type(inside);
7245         } else if (is_type_pointer(type_inside)) {
7246                 return_type             = type_inside->pointer.points_to;
7247                 array_access->array_ref = inside;
7248                 array_access->index     = left;
7249                 array_access->flipped   = true;
7250                 check_for_char_index_type(left);
7251         } else {
7252                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
7253                         errorf(HERE,
7254                                 "array access on object with non-pointer types '%T', '%T'",
7255                                 orig_type_left, orig_type_inside);
7256                 }
7257                 return_type             = type_error_type;
7258                 array_access->array_ref = left;
7259                 array_access->index     = inside;
7260         }
7261
7262         expression->base.type = automatic_type_conversion(return_type);
7263
7264         rem_anchor_token(']');
7265         if (token.type == ']') {
7266                 next_token();
7267         } else {
7268                 parse_error_expected("Problem while parsing array access", ']', NULL);
7269         }
7270         return expression;
7271 }
7272
7273 static expression_t *parse_typeprop(expression_kind_t const kind,
7274                                     source_position_t const pos)
7275 {
7276         expression_t  *tp_expression = allocate_expression_zero(kind);
7277         tp_expression->base.type            = type_size_t;
7278         tp_expression->base.source_position = pos;
7279
7280         char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7281
7282         /* we only refer to a type property, mark this case */
7283         bool old     = in_type_prop;
7284         in_type_prop = true;
7285         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
7286                 next_token();
7287                 add_anchor_token(')');
7288                 type_t* const orig_type = parse_typename();
7289                 tp_expression->typeprop.type = orig_type;
7290
7291                 type_t const* const type = skip_typeref(orig_type);
7292                 char const* const wrong_type =
7293                         is_type_incomplete(type)    ? "incomplete"          :
7294                         type->kind == TYPE_FUNCTION ? "function designator" :
7295                         type->kind == TYPE_BITFIELD ? "bitfield"            :
7296                         NULL;
7297                 if (wrong_type != NULL) {
7298                         errorf(&pos, "operand of %s expression must not be %s type '%T'",
7299                                what, wrong_type, type);
7300                 }
7301
7302                 rem_anchor_token(')');
7303                 expect(')');
7304         } else {
7305                 expression_t *expression = parse_sub_expression(PREC_UNARY);
7306
7307                 type_t* const orig_type = revert_automatic_type_conversion(expression);
7308                 expression->base.type = orig_type;
7309
7310                 type_t const* const type = skip_typeref(orig_type);
7311                 char const* const wrong_type =
7312                         is_type_incomplete(type)    ? "incomplete"          :
7313                         type->kind == TYPE_FUNCTION ? "function designator" :
7314                         type->kind == TYPE_BITFIELD ? "bitfield"            :
7315                         NULL;
7316                 if (wrong_type != NULL) {
7317                         errorf(&pos, "operand of %s expression must not be expression of %s type '%T'", what, wrong_type, type);
7318                 }
7319
7320                 tp_expression->typeprop.type          = expression->base.type;
7321                 tp_expression->typeprop.tp_expression = expression;
7322         }
7323
7324 end_error:
7325         in_type_prop = old;
7326         return tp_expression;
7327 }
7328
7329 static expression_t *parse_sizeof(void)
7330 {
7331         source_position_t pos = *HERE;
7332         eat(T_sizeof);
7333         return parse_typeprop(EXPR_SIZEOF, pos);
7334 }
7335
7336 static expression_t *parse_alignof(void)
7337 {
7338         source_position_t pos = *HERE;
7339         eat(T___alignof__);
7340         return parse_typeprop(EXPR_ALIGNOF, pos);
7341 }
7342
7343 static expression_t *parse_select_expression(expression_t *compound)
7344 {
7345         assert(token.type == '.' || token.type == T_MINUSGREATER);
7346
7347         bool is_pointer = (token.type == T_MINUSGREATER);
7348         next_token();
7349
7350         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
7351         select->select.compound = compound;
7352
7353         if (token.type != T_IDENTIFIER) {
7354                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
7355                 return select;
7356         }
7357         symbol_t *symbol = token.v.symbol;
7358         next_token();
7359
7360         type_t *const orig_type = compound->base.type;
7361         type_t *const type      = skip_typeref(orig_type);
7362
7363         type_t *type_left;
7364         bool    saw_error = false;
7365         if (is_type_pointer(type)) {
7366                 if (!is_pointer) {
7367                         errorf(HERE,
7368                                "request for member '%Y' in something not a struct or union, but '%T'",
7369                                symbol, orig_type);
7370                         saw_error = true;
7371                 }
7372                 type_left = skip_typeref(type->pointer.points_to);
7373         } else {
7374                 if (is_pointer && is_type_valid(type)) {
7375                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7376                         saw_error = true;
7377                 }
7378                 type_left = type;
7379         }
7380
7381         declaration_t *entry;
7382         if (type_left->kind == TYPE_COMPOUND_STRUCT ||
7383             type_left->kind == TYPE_COMPOUND_UNION) {
7384                 declaration_t *const declaration = type_left->compound.declaration;
7385
7386                 if (!declaration->init.complete) {
7387                         errorf(HERE, "request for member '%Y' of incomplete type '%T'",
7388                                symbol, type_left);
7389                         goto create_error_entry;
7390                 }
7391
7392                 entry = find_compound_entry(declaration, symbol);
7393                 if (entry == NULL) {
7394                         errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
7395                         goto create_error_entry;
7396                 }
7397         } else {
7398                 if (is_type_valid(type_left) && !saw_error) {
7399                         errorf(HERE,
7400                                "request for member '%Y' in something not a struct or union, but '%T'",
7401                                symbol, type_left);
7402                 }
7403 create_error_entry:
7404                 entry         = allocate_declaration_zero();
7405                 entry->symbol = symbol;
7406         }
7407
7408         select->select.compound_entry = entry;
7409
7410         type_t *const res_type =
7411                 get_qualified_type(entry->type, type_left->base.qualifiers);
7412
7413         /* we always do the auto-type conversions; the & and sizeof parser contains
7414          * code to revert this! */
7415         select->base.type = automatic_type_conversion(res_type);
7416
7417         type_t *skipped = skip_typeref(res_type);
7418         if (skipped->kind == TYPE_BITFIELD) {
7419                 select->base.type = skipped->bitfield.base_type;
7420         }
7421
7422         return select;
7423 }
7424
7425 static void check_call_argument(const function_parameter_t *parameter,
7426                                 call_argument_t *argument, unsigned pos)
7427 {
7428         type_t         *expected_type      = parameter->type;
7429         type_t         *expected_type_skip = skip_typeref(expected_type);
7430         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
7431         expression_t   *arg_expr           = argument->expression;
7432         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
7433
7434         /* handle transparent union gnu extension */
7435         if (is_type_union(expected_type_skip)
7436                         && (expected_type_skip->base.modifiers
7437                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
7438                 declaration_t  *union_decl = expected_type_skip->compound.declaration;
7439
7440                 declaration_t *declaration = union_decl->scope.declarations;
7441                 type_t        *best_type   = NULL;
7442                 for ( ; declaration != NULL; declaration = declaration->next) {
7443                         type_t *decl_type = declaration->type;
7444                         error = semantic_assign(decl_type, arg_expr);
7445                         if (error == ASSIGN_ERROR_INCOMPATIBLE
7446                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
7447                                 continue;
7448
7449                         if (error == ASSIGN_SUCCESS) {
7450                                 best_type = decl_type;
7451                         } else if (best_type == NULL) {
7452                                 best_type = decl_type;
7453                         }
7454                 }
7455
7456                 if (best_type != NULL) {
7457                         expected_type = best_type;
7458                 }
7459         }
7460
7461         error                = semantic_assign(expected_type, arg_expr);
7462         argument->expression = create_implicit_cast(argument->expression,
7463                                                     expected_type);
7464
7465         if (error != ASSIGN_SUCCESS) {
7466                 /* report exact scope in error messages (like "in argument 3") */
7467                 char buf[64];
7468                 snprintf(buf, sizeof(buf), "call argument %u", pos);
7469                 report_assign_error(error, expected_type, arg_expr,     buf,
7470                                                         &arg_expr->base.source_position);
7471         } else if (warning.traditional || warning.conversion) {
7472                 type_t *const promoted_type = get_default_promoted_type(arg_type);
7473                 if (!types_compatible(expected_type_skip, promoted_type) &&
7474                     !types_compatible(expected_type_skip, type_void_ptr) &&
7475                     !types_compatible(type_void_ptr,      promoted_type)) {
7476                         /* Deliberately show the skipped types in this warning */
7477                         warningf(&arg_expr->base.source_position,
7478                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
7479                                 pos, expected_type_skip, promoted_type);
7480                 }
7481         }
7482 }
7483
7484 /**
7485  * Parse a call expression, ie. expression '( ... )'.
7486  *
7487  * @param expression  the function address
7488  */
7489 static expression_t *parse_call_expression(expression_t *expression)
7490 {
7491         expression_t *result = allocate_expression_zero(EXPR_CALL);
7492         result->base.source_position = expression->base.source_position;
7493
7494         call_expression_t *call = &result->call;
7495         call->function          = expression;
7496
7497         type_t *const orig_type = expression->base.type;
7498         type_t *const type      = skip_typeref(orig_type);
7499
7500         function_type_t *function_type = NULL;
7501         if (is_type_pointer(type)) {
7502                 type_t *const to_type = skip_typeref(type->pointer.points_to);
7503
7504                 if (is_type_function(to_type)) {
7505                         function_type   = &to_type->function;
7506                         call->base.type = function_type->return_type;
7507                 }
7508         }
7509
7510         if (function_type == NULL && is_type_valid(type)) {
7511                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
7512         }
7513
7514         /* parse arguments */
7515         eat('(');
7516         add_anchor_token(')');
7517         add_anchor_token(',');
7518
7519         if (token.type != ')') {
7520                 call_argument_t *last_argument = NULL;
7521
7522                 while (true) {
7523                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
7524
7525                         argument->expression = parse_assignment_expression();
7526                         if (last_argument == NULL) {
7527                                 call->arguments = argument;
7528                         } else {
7529                                 last_argument->next = argument;
7530                         }
7531                         last_argument = argument;
7532
7533                         if (token.type != ',')
7534                                 break;
7535                         next_token();
7536                 }
7537         }
7538         rem_anchor_token(',');
7539         rem_anchor_token(')');
7540         expect(')');
7541
7542         if (function_type == NULL)
7543                 return result;
7544
7545         function_parameter_t *parameter = function_type->parameters;
7546         call_argument_t      *argument  = call->arguments;
7547         if (!function_type->unspecified_parameters) {
7548                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
7549                                 parameter = parameter->next, argument = argument->next) {
7550                         check_call_argument(parameter, argument, ++pos);
7551                 }
7552
7553                 if (parameter != NULL) {
7554                         errorf(HERE, "too few arguments to function '%E'", expression);
7555                 } else if (argument != NULL && !function_type->variadic) {
7556                         errorf(HERE, "too many arguments to function '%E'", expression);
7557                 }
7558         }
7559
7560         /* do default promotion */
7561         for( ; argument != NULL; argument = argument->next) {
7562                 type_t *type = argument->expression->base.type;
7563
7564                 type = get_default_promoted_type(type);
7565
7566                 argument->expression
7567                         = create_implicit_cast(argument->expression, type);
7568         }
7569
7570         check_format(&result->call);
7571
7572         if (warning.aggregate_return &&
7573             is_type_compound(skip_typeref(function_type->return_type))) {
7574                 warningf(&result->base.source_position,
7575                          "function call has aggregate value");
7576         }
7577
7578 end_error:
7579         return result;
7580 }
7581
7582 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
7583
7584 static bool same_compound_type(const type_t *type1, const type_t *type2)
7585 {
7586         return
7587                 is_type_compound(type1) &&
7588                 type1->kind == type2->kind &&
7589                 type1->compound.declaration == type2->compound.declaration;
7590 }
7591
7592 /**
7593  * Parse a conditional expression, ie. 'expression ? ... : ...'.
7594  *
7595  * @param expression  the conditional expression
7596  */
7597 static expression_t *parse_conditional_expression(expression_t *expression)
7598 {
7599         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
7600
7601         conditional_expression_t *conditional = &result->conditional;
7602         conditional->base.source_position = *HERE;
7603         conditional->condition            = expression;
7604
7605         eat('?');
7606         add_anchor_token(':');
7607
7608         /* 6.5.15.2 */
7609         type_t *const condition_type_orig = expression->base.type;
7610         type_t *const condition_type      = skip_typeref(condition_type_orig);
7611         if (!is_type_scalar(condition_type) && is_type_valid(condition_type)) {
7612                 type_error("expected a scalar type in conditional condition",
7613                            &expression->base.source_position, condition_type_orig);
7614         }
7615
7616         expression_t *true_expression = expression;
7617         bool          gnu_cond = false;
7618         if (GNU_MODE && token.type == ':') {
7619                 gnu_cond = true;
7620         } else
7621                 true_expression = parse_expression();
7622         rem_anchor_token(':');
7623         expect(':');
7624         expression_t *false_expression =
7625                 parse_sub_expression(c_mode & _CXX ? PREC_ASSIGNMENT : PREC_CONDITIONAL);
7626
7627         type_t *const orig_true_type  = true_expression->base.type;
7628         type_t *const orig_false_type = false_expression->base.type;
7629         type_t *const true_type       = skip_typeref(orig_true_type);
7630         type_t *const false_type      = skip_typeref(orig_false_type);
7631
7632         /* 6.5.15.3 */
7633         type_t *result_type;
7634         if (is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
7635                         is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7636                 /* ISO/IEC 14882:1998(E) §5.16:2 */
7637                 if (true_expression->kind == EXPR_UNARY_THROW) {
7638                         result_type = false_type;
7639                 } else if (false_expression->kind == EXPR_UNARY_THROW) {
7640                         result_type = true_type;
7641                 } else {
7642                         if (warning.other && (
7643                                                 !is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
7644                                                 !is_type_atomic(false_type, ATOMIC_TYPE_VOID)
7645                                         )) {
7646                                 warningf(&conditional->base.source_position,
7647                                                 "ISO C forbids conditional expression with only one void side");
7648                         }
7649                         result_type = type_void;
7650                 }
7651         } else if (is_type_arithmetic(true_type)
7652                    && is_type_arithmetic(false_type)) {
7653                 result_type = semantic_arithmetic(true_type, false_type);
7654
7655                 true_expression  = create_implicit_cast(true_expression, result_type);
7656                 false_expression = create_implicit_cast(false_expression, result_type);
7657
7658                 conditional->true_expression  = true_expression;
7659                 conditional->false_expression = false_expression;
7660                 conditional->base.type        = result_type;
7661         } else if (same_compound_type(true_type, false_type)) {
7662                 /* just take 1 of the 2 types */
7663                 result_type = true_type;
7664         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
7665                 type_t *pointer_type;
7666                 type_t *other_type;
7667                 expression_t *other_expression;
7668                 if (is_type_pointer(true_type) &&
7669                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
7670                         pointer_type     = true_type;
7671                         other_type       = false_type;
7672                         other_expression = false_expression;
7673                 } else {
7674                         pointer_type     = false_type;
7675                         other_type       = true_type;
7676                         other_expression = true_expression;
7677                 }
7678
7679                 if (is_null_pointer_constant(other_expression)) {
7680                         result_type = pointer_type;
7681                 } else if (is_type_pointer(other_type)) {
7682                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
7683                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
7684
7685                         type_t *to;
7686                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
7687                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
7688                                 to = type_void;
7689                         } else if (types_compatible(get_unqualified_type(to1),
7690                                                     get_unqualified_type(to2))) {
7691                                 to = to1;
7692                         } else {
7693                                 if (warning.other) {
7694                                         warningf(&conditional->base.source_position,
7695                                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
7696                                                         true_type, false_type);
7697                                 }
7698                                 to = type_void;
7699                         }
7700
7701                         type_t *const type =
7702                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
7703                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
7704                 } else if (is_type_integer(other_type)) {
7705                         if (warning.other) {
7706                                 warningf(&conditional->base.source_position,
7707                                                 "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
7708                         }
7709                         result_type = pointer_type;
7710                 } else {
7711                         if (is_type_valid(other_type)) {
7712                                 type_error_incompatible("while parsing conditional",
7713                                                 &expression->base.source_position, true_type, false_type);
7714                         }
7715                         result_type = type_error_type;
7716                 }
7717         } else {
7718                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
7719                         type_error_incompatible("while parsing conditional",
7720                                                 &conditional->base.source_position, true_type,
7721                                                 false_type);
7722                 }
7723                 result_type = type_error_type;
7724         }
7725
7726         conditional->true_expression
7727                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
7728         conditional->false_expression
7729                 = create_implicit_cast(false_expression, result_type);
7730         conditional->base.type = result_type;
7731         return result;
7732 end_error:
7733         return create_invalid_expression();
7734 }
7735
7736 /**
7737  * Parse an extension expression.
7738  */
7739 static expression_t *parse_extension(void)
7740 {
7741         eat(T___extension__);
7742
7743         bool old_gcc_extension   = in_gcc_extension;
7744         in_gcc_extension         = true;
7745         expression_t *expression = parse_sub_expression(PREC_UNARY);
7746         in_gcc_extension         = old_gcc_extension;
7747         return expression;
7748 }
7749
7750 /**
7751  * Parse a __builtin_classify_type() expression.
7752  */
7753 static expression_t *parse_builtin_classify_type(void)
7754 {
7755         eat(T___builtin_classify_type);
7756
7757         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
7758         result->base.type    = type_int;
7759
7760         expect('(');
7761         add_anchor_token(')');
7762         expression_t *expression = parse_expression();
7763         rem_anchor_token(')');
7764         expect(')');
7765         result->classify_type.type_expression = expression;
7766
7767         return result;
7768 end_error:
7769         return create_invalid_expression();
7770 }
7771
7772 /**
7773  * Parse a throw expression
7774  * ISO/IEC 14882:1998(E) §15:1
7775  */
7776 static expression_t *parse_throw(void)
7777 {
7778         expression_t *const result = allocate_expression_zero(EXPR_UNARY_THROW);
7779         result->base.source_position = *HERE;
7780         result->base.type            = type_void;
7781
7782         eat(T_throw);
7783
7784         expression_t *value = NULL;
7785         switch (token.type) {
7786                 EXPRESSION_START {
7787                         value = parse_assignment_expression();
7788                         /* ISO/IEC 14882:1998(E) §15.1:3 */
7789                         type_t *const orig_type = value->base.type;
7790                         type_t *const type      = skip_typeref(orig_type);
7791                         if (is_type_incomplete(type)) {
7792                                 errorf(&value->base.source_position,
7793                                                 "cannot throw object of incomplete type '%T'", orig_type);
7794                         } else if (is_type_pointer(type)) {
7795                                 type_t *const points_to = skip_typeref(type->pointer.points_to);
7796                                 if (is_type_incomplete(points_to) &&
7797                                                 !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7798                                         errorf(&value->base.source_position,
7799                                                         "cannot throw pointer to incomplete type '%T'", orig_type);
7800                                 }
7801                         }
7802                 }
7803
7804                 default:
7805                         break;
7806         }
7807         result->unary.value = value;
7808
7809         return result;
7810 }
7811
7812 static bool check_pointer_arithmetic(const source_position_t *source_position,
7813                                      type_t *pointer_type,
7814                                      type_t *orig_pointer_type)
7815 {
7816         type_t *points_to = pointer_type->pointer.points_to;
7817         points_to = skip_typeref(points_to);
7818
7819         if (is_type_incomplete(points_to)) {
7820                 if (!GNU_MODE || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7821                         errorf(source_position,
7822                                "arithmetic with pointer to incomplete type '%T' not allowed",
7823                                orig_pointer_type);
7824                         return false;
7825                 } else if (warning.pointer_arith) {
7826                         warningf(source_position,
7827                                  "pointer of type '%T' used in arithmetic",
7828                                  orig_pointer_type);
7829                 }
7830         } else if (is_type_function(points_to)) {
7831                 if (!GNU_MODE) {
7832                         errorf(source_position,
7833                                "arithmetic with pointer to function type '%T' not allowed",
7834                                orig_pointer_type);
7835                         return false;
7836                 } else if (warning.pointer_arith) {
7837                         warningf(source_position,
7838                                  "pointer to a function '%T' used in arithmetic",
7839                                  orig_pointer_type);
7840                 }
7841         }
7842         return true;
7843 }
7844
7845 static bool is_lvalue(const expression_t *expression)
7846 {
7847         switch (expression->kind) {
7848         case EXPR_REFERENCE:
7849         case EXPR_ARRAY_ACCESS:
7850         case EXPR_SELECT:
7851         case EXPR_UNARY_DEREFERENCE:
7852                 return true;
7853
7854         default:
7855                 /* Claim it is an lvalue, if the type is invalid.  There was a parse
7856                  * error before, which maybe prevented properly recognizing it as
7857                  * lvalue. */
7858                 return !is_type_valid(skip_typeref(expression->base.type));
7859         }
7860 }
7861
7862 static void semantic_incdec(unary_expression_t *expression)
7863 {
7864         type_t *const orig_type = expression->value->base.type;
7865         type_t *const type      = skip_typeref(orig_type);
7866         if (is_type_pointer(type)) {
7867                 if (!check_pointer_arithmetic(&expression->base.source_position,
7868                                               type, orig_type)) {
7869                         return;
7870                 }
7871         } else if (!is_type_real(type) && is_type_valid(type)) {
7872                 /* TODO: improve error message */
7873                 errorf(&expression->base.source_position,
7874                        "operation needs an arithmetic or pointer type");
7875                 return;
7876         }
7877         if (!is_lvalue(expression->value)) {
7878                 /* TODO: improve error message */
7879                 errorf(&expression->base.source_position, "lvalue required as operand");
7880         }
7881         expression->base.type = orig_type;
7882 }
7883
7884 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
7885 {
7886         type_t *const orig_type = expression->value->base.type;
7887         type_t *const type      = skip_typeref(orig_type);
7888         if (!is_type_arithmetic(type)) {
7889                 if (is_type_valid(type)) {
7890                         /* TODO: improve error message */
7891                         errorf(&expression->base.source_position,
7892                                 "operation needs an arithmetic type");
7893                 }
7894                 return;
7895         }
7896
7897         expression->base.type = orig_type;
7898 }
7899
7900 static void semantic_unexpr_plus(unary_expression_t *expression)
7901 {
7902         semantic_unexpr_arithmetic(expression);
7903         if (warning.traditional)
7904                 warningf(&expression->base.source_position,
7905                         "traditional C rejects the unary plus operator");
7906 }
7907
7908 static expression_t const *get_reference_address(expression_t const *expr)
7909 {
7910         bool regular_take_address = true;
7911         for (;;) {
7912                 if (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
7913                         expr = expr->unary.value;
7914                 } else {
7915                         regular_take_address = false;
7916                 }
7917
7918                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
7919                         break;
7920
7921                 expr = expr->unary.value;
7922         }
7923
7924         if (expr->kind != EXPR_REFERENCE)
7925                 return NULL;
7926
7927         if (!regular_take_address &&
7928             !is_type_function(skip_typeref(expr->reference.declaration->type))) {
7929                 return NULL;
7930         }
7931
7932         return expr;
7933 }
7934
7935 static void warn_function_address_as_bool(expression_t const* expr)
7936 {
7937         if (!warning.address)
7938                 return;
7939
7940         expr = get_reference_address(expr);
7941         if (expr != NULL) {
7942                 warningf(&expr->base.source_position,
7943                         "the address of '%Y' will always evaluate as 'true'",
7944                         expr->reference.declaration->symbol);
7945         }
7946 }
7947
7948 static void semantic_not(unary_expression_t *expression)
7949 {
7950         type_t *const orig_type = expression->value->base.type;
7951         type_t *const type      = skip_typeref(orig_type);
7952         if (!is_type_scalar(type) && is_type_valid(type)) {
7953                 errorf(&expression->base.source_position,
7954                        "operand of ! must be of scalar type");
7955         }
7956
7957         warn_function_address_as_bool(expression->value);
7958
7959         expression->base.type = type_int;
7960 }
7961
7962 static void semantic_unexpr_integer(unary_expression_t *expression)
7963 {
7964         type_t *const orig_type = expression->value->base.type;
7965         type_t *const type      = skip_typeref(orig_type);
7966         if (!is_type_integer(type)) {
7967                 if (is_type_valid(type)) {
7968                         errorf(&expression->base.source_position,
7969                                "operand of ~ must be of integer type");
7970                 }
7971                 return;
7972         }
7973
7974         expression->base.type = orig_type;
7975 }
7976
7977 static void semantic_dereference(unary_expression_t *expression)
7978 {
7979         type_t *const orig_type = expression->value->base.type;
7980         type_t *const type      = skip_typeref(orig_type);
7981         if (!is_type_pointer(type)) {
7982                 if (is_type_valid(type)) {
7983                         errorf(&expression->base.source_position,
7984                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
7985                 }
7986                 return;
7987         }
7988
7989         type_t *result_type   = type->pointer.points_to;
7990         result_type           = automatic_type_conversion(result_type);
7991         expression->base.type = result_type;
7992 }
7993
7994 /**
7995  * Record that an address is taken (expression represents an lvalue).
7996  *
7997  * @param expression       the expression
7998  * @param may_be_register  if true, the expression might be an register
7999  */
8000 static void set_address_taken(expression_t *expression, bool may_be_register)
8001 {
8002         if (expression->kind != EXPR_REFERENCE)
8003                 return;
8004
8005         declaration_t *const declaration = expression->reference.declaration;
8006         /* happens for parse errors */
8007         if (declaration == NULL)
8008                 return;
8009
8010         if (declaration->storage_class == STORAGE_CLASS_REGISTER && !may_be_register) {
8011                 errorf(&expression->base.source_position,
8012                                 "address of register variable '%Y' requested",
8013                                 declaration->symbol);
8014         } else {
8015                 declaration->address_taken = 1;
8016         }
8017 }
8018
8019 /**
8020  * Check the semantic of the address taken expression.
8021  */
8022 static void semantic_take_addr(unary_expression_t *expression)
8023 {
8024         expression_t *value = expression->value;
8025         value->base.type    = revert_automatic_type_conversion(value);
8026
8027         type_t *orig_type = value->base.type;
8028         if (!is_type_valid(skip_typeref(orig_type)))
8029                 return;
8030
8031         set_address_taken(value, false);
8032
8033         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
8034 }
8035
8036 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc) \
8037 static expression_t *parse_##unexpression_type(void)                         \
8038 {                                                                            \
8039         expression_t *unary_expression                                           \
8040                 = allocate_expression_zero(unexpression_type);                       \
8041         unary_expression->base.source_position = *HERE;                          \
8042         eat(token_type);                                                         \
8043         unary_expression->unary.value = parse_sub_expression(PREC_UNARY);        \
8044                                                                                  \
8045         sfunc(&unary_expression->unary);                                         \
8046                                                                                  \
8047         return unary_expression;                                                 \
8048 }
8049
8050 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
8051                                semantic_unexpr_arithmetic)
8052 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
8053                                semantic_unexpr_plus)
8054 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
8055                                semantic_not)
8056 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
8057                                semantic_dereference)
8058 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
8059                                semantic_take_addr)
8060 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
8061                                semantic_unexpr_integer)
8062 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
8063                                semantic_incdec)
8064 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
8065                                semantic_incdec)
8066
8067 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
8068                                                sfunc)                         \
8069 static expression_t *parse_##unexpression_type(expression_t *left)            \
8070 {                                                                             \
8071         expression_t *unary_expression                                            \
8072                 = allocate_expression_zero(unexpression_type);                        \
8073         unary_expression->base.source_position = *HERE;                           \
8074         eat(token_type);                                                          \
8075         unary_expression->unary.value          = left;                            \
8076                                                                                   \
8077         sfunc(&unary_expression->unary);                                          \
8078                                                                               \
8079         return unary_expression;                                                  \
8080 }
8081
8082 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
8083                                        EXPR_UNARY_POSTFIX_INCREMENT,
8084                                        semantic_incdec)
8085 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
8086                                        EXPR_UNARY_POSTFIX_DECREMENT,
8087                                        semantic_incdec)
8088
8089 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
8090 {
8091         /* TODO: handle complex + imaginary types */
8092
8093         type_left  = get_unqualified_type(type_left);
8094         type_right = get_unqualified_type(type_right);
8095
8096         /* § 6.3.1.8 Usual arithmetic conversions */
8097         if (type_left == type_long_double || type_right == type_long_double) {
8098                 return type_long_double;
8099         } else if (type_left == type_double || type_right == type_double) {
8100                 return type_double;
8101         } else if (type_left == type_float || type_right == type_float) {
8102                 return type_float;
8103         }
8104
8105         type_left  = promote_integer(type_left);
8106         type_right = promote_integer(type_right);
8107
8108         if (type_left == type_right)
8109                 return type_left;
8110
8111         bool const signed_left  = is_type_signed(type_left);
8112         bool const signed_right = is_type_signed(type_right);
8113         int const  rank_left    = get_rank(type_left);
8114         int const  rank_right   = get_rank(type_right);
8115
8116         if (signed_left == signed_right)
8117                 return rank_left >= rank_right ? type_left : type_right;
8118
8119         int     s_rank;
8120         int     u_rank;
8121         type_t *s_type;
8122         type_t *u_type;
8123         if (signed_left) {
8124                 s_rank = rank_left;
8125                 s_type = type_left;
8126                 u_rank = rank_right;
8127                 u_type = type_right;
8128         } else {
8129                 s_rank = rank_right;
8130                 s_type = type_right;
8131                 u_rank = rank_left;
8132                 u_type = type_left;
8133         }
8134
8135         if (u_rank >= s_rank)
8136                 return u_type;
8137
8138         /* casting rank to atomic_type_kind is a bit hacky, but makes things
8139          * easier here... */
8140         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
8141                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
8142                 return s_type;
8143
8144         switch (s_rank) {
8145                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
8146                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
8147                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
8148
8149                 default: panic("invalid atomic type");
8150         }
8151 }
8152
8153 /**
8154  * Check the semantic restrictions for a binary expression.
8155  */
8156 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
8157 {
8158         expression_t *const left            = expression->left;
8159         expression_t *const right           = expression->right;
8160         type_t       *const orig_type_left  = left->base.type;
8161         type_t       *const orig_type_right = right->base.type;
8162         type_t       *const type_left       = skip_typeref(orig_type_left);
8163         type_t       *const type_right      = skip_typeref(orig_type_right);
8164
8165         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8166                 /* TODO: improve error message */
8167                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8168                         errorf(&expression->base.source_position,
8169                                "operation needs arithmetic types");
8170                 }
8171                 return;
8172         }
8173
8174         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8175         expression->left      = create_implicit_cast(left, arithmetic_type);
8176         expression->right     = create_implicit_cast(right, arithmetic_type);
8177         expression->base.type = arithmetic_type;
8178 }
8179
8180 static void warn_div_by_zero(binary_expression_t const *const expression)
8181 {
8182         if (!warning.div_by_zero ||
8183             !is_type_integer(expression->base.type))
8184                 return;
8185
8186         expression_t const *const right = expression->right;
8187         /* The type of the right operand can be different for /= */
8188         if (is_type_integer(right->base.type) &&
8189             is_constant_expression(right)     &&
8190             fold_constant(right) == 0) {
8191                 warningf(&expression->base.source_position, "division by zero");
8192         }
8193 }
8194
8195 /**
8196  * Check the semantic restrictions for a div/mod expression.
8197  */
8198 static void semantic_divmod_arithmetic(binary_expression_t *expression) {
8199         semantic_binexpr_arithmetic(expression);
8200         warn_div_by_zero(expression);
8201 }
8202
8203 static void semantic_shift_op(binary_expression_t *expression)
8204 {
8205         expression_t *const left            = expression->left;
8206         expression_t *const right           = expression->right;
8207         type_t       *const orig_type_left  = left->base.type;
8208         type_t       *const orig_type_right = right->base.type;
8209         type_t       *      type_left       = skip_typeref(orig_type_left);
8210         type_t       *      type_right      = skip_typeref(orig_type_right);
8211
8212         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8213                 /* TODO: improve error message */
8214                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8215                         errorf(&expression->base.source_position,
8216                                "operands of shift operation must have integer types");
8217                 }
8218                 return;
8219         }
8220
8221         type_left  = promote_integer(type_left);
8222         type_right = promote_integer(type_right);
8223
8224         expression->left      = create_implicit_cast(left, type_left);
8225         expression->right     = create_implicit_cast(right, type_right);
8226         expression->base.type = type_left;
8227 }
8228
8229 static void semantic_add(binary_expression_t *expression)
8230 {
8231         expression_t *const left            = expression->left;
8232         expression_t *const right           = expression->right;
8233         type_t       *const orig_type_left  = left->base.type;
8234         type_t       *const orig_type_right = right->base.type;
8235         type_t       *const type_left       = skip_typeref(orig_type_left);
8236         type_t       *const type_right      = skip_typeref(orig_type_right);
8237
8238         /* § 6.5.6 */
8239         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8240                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8241                 expression->left  = create_implicit_cast(left, arithmetic_type);
8242                 expression->right = create_implicit_cast(right, arithmetic_type);
8243                 expression->base.type = arithmetic_type;
8244                 return;
8245         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8246                 check_pointer_arithmetic(&expression->base.source_position,
8247                                          type_left, orig_type_left);
8248                 expression->base.type = type_left;
8249         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
8250                 check_pointer_arithmetic(&expression->base.source_position,
8251                                          type_right, orig_type_right);
8252                 expression->base.type = type_right;
8253         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8254                 errorf(&expression->base.source_position,
8255                        "invalid operands to binary + ('%T', '%T')",
8256                        orig_type_left, orig_type_right);
8257         }
8258 }
8259
8260 static void semantic_sub(binary_expression_t *expression)
8261 {
8262         expression_t            *const left            = expression->left;
8263         expression_t            *const right           = expression->right;
8264         type_t                  *const orig_type_left  = left->base.type;
8265         type_t                  *const orig_type_right = right->base.type;
8266         type_t                  *const type_left       = skip_typeref(orig_type_left);
8267         type_t                  *const type_right      = skip_typeref(orig_type_right);
8268         source_position_t const *const pos             = &expression->base.source_position;
8269
8270         /* § 5.6.5 */
8271         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8272                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8273                 expression->left        = create_implicit_cast(left, arithmetic_type);
8274                 expression->right       = create_implicit_cast(right, arithmetic_type);
8275                 expression->base.type =  arithmetic_type;
8276                 return;
8277         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8278                 check_pointer_arithmetic(&expression->base.source_position,
8279                                          type_left, orig_type_left);
8280                 expression->base.type = type_left;
8281         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8282                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
8283                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
8284                 if (!types_compatible(unqual_left, unqual_right)) {
8285                         errorf(pos,
8286                                "subtracting pointers to incompatible types '%T' and '%T'",
8287                                orig_type_left, orig_type_right);
8288                 } else if (!is_type_object(unqual_left)) {
8289                         if (!is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
8290                                 errorf(pos, "subtracting pointers to non-object types '%T'",
8291                                        orig_type_left);
8292                         } else if (warning.other) {
8293                                 warningf(pos, "subtracting pointers to void");
8294                         }
8295                 }
8296                 expression->base.type = type_ptrdiff_t;
8297         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8298                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
8299                        orig_type_left, orig_type_right);
8300         }
8301 }
8302
8303 static void warn_string_literal_address(expression_t const* expr)
8304 {
8305         while (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8306                 expr = expr->unary.value;
8307                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8308                         return;
8309                 expr = expr->unary.value;
8310         }
8311
8312         if (expr->kind == EXPR_STRING_LITERAL ||
8313             expr->kind == EXPR_WIDE_STRING_LITERAL) {
8314                 warningf(&expr->base.source_position,
8315                         "comparison with string literal results in unspecified behaviour");
8316         }
8317 }
8318
8319 /**
8320  * Check the semantics of comparison expressions.
8321  *
8322  * @param expression   The expression to check.
8323  */
8324 static void semantic_comparison(binary_expression_t *expression)
8325 {
8326         expression_t *left  = expression->left;
8327         expression_t *right = expression->right;
8328
8329         if (warning.address) {
8330                 warn_string_literal_address(left);
8331                 warn_string_literal_address(right);
8332
8333                 expression_t const* const func_left = get_reference_address(left);
8334                 if (func_left != NULL && is_null_pointer_constant(right)) {
8335                         warningf(&expression->base.source_position,
8336                                 "the address of '%Y' will never be NULL",
8337                                 func_left->reference.declaration->symbol);
8338                 }
8339
8340                 expression_t const* const func_right = get_reference_address(right);
8341                 if (func_right != NULL && is_null_pointer_constant(right)) {
8342                         warningf(&expression->base.source_position,
8343                                 "the address of '%Y' will never be NULL",
8344                                 func_right->reference.declaration->symbol);
8345                 }
8346         }
8347
8348         type_t *orig_type_left  = left->base.type;
8349         type_t *orig_type_right = right->base.type;
8350         type_t *type_left       = skip_typeref(orig_type_left);
8351         type_t *type_right      = skip_typeref(orig_type_right);
8352
8353         /* TODO non-arithmetic types */
8354         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8355                 /* test for signed vs unsigned compares */
8356                 if (warning.sign_compare &&
8357                     (expression->base.kind != EXPR_BINARY_EQUAL &&
8358                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
8359                     (is_type_signed(type_left) != is_type_signed(type_right))) {
8360
8361                         /* check if 1 of the operands is a constant, in this case we just
8362                          * check wether we can safely represent the resulting constant in
8363                          * the type of the other operand. */
8364                         expression_t *const_expr = NULL;
8365                         expression_t *other_expr = NULL;
8366
8367                         if (is_constant_expression(left)) {
8368                                 const_expr = left;
8369                                 other_expr = right;
8370                         } else if (is_constant_expression(right)) {
8371                                 const_expr = right;
8372                                 other_expr = left;
8373                         }
8374
8375                         if (const_expr != NULL) {
8376                                 type_t *other_type = skip_typeref(other_expr->base.type);
8377                                 long    val        = fold_constant(const_expr);
8378                                 /* TODO: check if val can be represented by other_type */
8379                                 (void) other_type;
8380                                 (void) val;
8381                         }
8382                         warningf(&expression->base.source_position,
8383                                  "comparison between signed and unsigned");
8384                 }
8385                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8386                 expression->left        = create_implicit_cast(left, arithmetic_type);
8387                 expression->right       = create_implicit_cast(right, arithmetic_type);
8388                 expression->base.type   = arithmetic_type;
8389                 if (warning.float_equal &&
8390                     (expression->base.kind == EXPR_BINARY_EQUAL ||
8391                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
8392                     is_type_float(arithmetic_type)) {
8393                         warningf(&expression->base.source_position,
8394                                  "comparing floating point with == or != is unsafe");
8395                 }
8396         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8397                 /* TODO check compatibility */
8398         } else if (is_type_pointer(type_left)) {
8399                 expression->right = create_implicit_cast(right, type_left);
8400         } else if (is_type_pointer(type_right)) {
8401                 expression->left = create_implicit_cast(left, type_right);
8402         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8403                 type_error_incompatible("invalid operands in comparison",
8404                                         &expression->base.source_position,
8405                                         type_left, type_right);
8406         }
8407         expression->base.type = type_int;
8408 }
8409
8410 /**
8411  * Checks if a compound type has constant fields.
8412  */
8413 static bool has_const_fields(const compound_type_t *type)
8414 {
8415         const scope_t       *scope       = &type->declaration->scope;
8416         const declaration_t *declaration = scope->declarations;
8417
8418         for (; declaration != NULL; declaration = declaration->next) {
8419                 if (declaration->namespc != NAMESPACE_NORMAL)
8420                         continue;
8421
8422                 const type_t *decl_type = skip_typeref(declaration->type);
8423                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
8424                         return true;
8425         }
8426         /* TODO */
8427         return false;
8428 }
8429
8430 static bool is_valid_assignment_lhs(expression_t const* const left)
8431 {
8432         type_t *const orig_type_left = revert_automatic_type_conversion(left);
8433         type_t *const type_left      = skip_typeref(orig_type_left);
8434
8435         if (!is_lvalue(left)) {
8436                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
8437                        left);
8438                 return false;
8439         }
8440
8441         if (is_type_array(type_left)) {
8442                 errorf(HERE, "cannot assign to arrays ('%E')", left);
8443                 return false;
8444         }
8445         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
8446                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
8447                        orig_type_left);
8448                 return false;
8449         }
8450         if (is_type_incomplete(type_left)) {
8451                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
8452                        left, orig_type_left);
8453                 return false;
8454         }
8455         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
8456                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
8457                        left, orig_type_left);
8458                 return false;
8459         }
8460
8461         return true;
8462 }
8463
8464 static void semantic_arithmetic_assign(binary_expression_t *expression)
8465 {
8466         expression_t *left            = expression->left;
8467         expression_t *right           = expression->right;
8468         type_t       *orig_type_left  = left->base.type;
8469         type_t       *orig_type_right = right->base.type;
8470
8471         if (!is_valid_assignment_lhs(left))
8472                 return;
8473
8474         type_t *type_left  = skip_typeref(orig_type_left);
8475         type_t *type_right = skip_typeref(orig_type_right);
8476
8477         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8478                 /* TODO: improve error message */
8479                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8480                         errorf(&expression->base.source_position,
8481                                "operation needs arithmetic types");
8482                 }
8483                 return;
8484         }
8485
8486         /* combined instructions are tricky. We can't create an implicit cast on
8487          * the left side, because we need the uncasted form for the store.
8488          * The ast2firm pass has to know that left_type must be right_type
8489          * for the arithmetic operation and create a cast by itself */
8490         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8491         expression->right       = create_implicit_cast(right, arithmetic_type);
8492         expression->base.type   = type_left;
8493 }
8494
8495 static void semantic_divmod_assign(binary_expression_t *expression)
8496 {
8497         semantic_arithmetic_assign(expression);
8498         warn_div_by_zero(expression);
8499 }
8500
8501 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
8502 {
8503         expression_t *const left            = expression->left;
8504         expression_t *const right           = expression->right;
8505         type_t       *const orig_type_left  = left->base.type;
8506         type_t       *const orig_type_right = right->base.type;
8507         type_t       *const type_left       = skip_typeref(orig_type_left);
8508         type_t       *const type_right      = skip_typeref(orig_type_right);
8509
8510         if (!is_valid_assignment_lhs(left))
8511                 return;
8512
8513         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8514                 /* combined instructions are tricky. We can't create an implicit cast on
8515                  * the left side, because we need the uncasted form for the store.
8516                  * The ast2firm pass has to know that left_type must be right_type
8517                  * for the arithmetic operation and create a cast by itself */
8518                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
8519                 expression->right     = create_implicit_cast(right, arithmetic_type);
8520                 expression->base.type = type_left;
8521         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8522                 check_pointer_arithmetic(&expression->base.source_position,
8523                                          type_left, orig_type_left);
8524                 expression->base.type = type_left;
8525         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8526                 errorf(&expression->base.source_position,
8527                        "incompatible types '%T' and '%T' in assignment",
8528                        orig_type_left, orig_type_right);
8529         }
8530 }
8531
8532 /**
8533  * Check the semantic restrictions of a logical expression.
8534  */
8535 static void semantic_logical_op(binary_expression_t *expression)
8536 {
8537         expression_t *const left            = expression->left;
8538         expression_t *const right           = expression->right;
8539         type_t       *const orig_type_left  = left->base.type;
8540         type_t       *const orig_type_right = right->base.type;
8541         type_t       *const type_left       = skip_typeref(orig_type_left);
8542         type_t       *const type_right      = skip_typeref(orig_type_right);
8543
8544         warn_function_address_as_bool(left);
8545         warn_function_address_as_bool(right);
8546
8547         if (!is_type_scalar(type_left) || !is_type_scalar(type_right)) {
8548                 /* TODO: improve error message */
8549                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8550                         errorf(&expression->base.source_position,
8551                                "operation needs scalar types");
8552                 }
8553                 return;
8554         }
8555
8556         expression->base.type = type_int;
8557 }
8558
8559 /**
8560  * Check the semantic restrictions of a binary assign expression.
8561  */
8562 static void semantic_binexpr_assign(binary_expression_t *expression)
8563 {
8564         expression_t *left           = expression->left;
8565         type_t       *orig_type_left = left->base.type;
8566
8567         if (!is_valid_assignment_lhs(left))
8568                 return;
8569
8570         assign_error_t error = semantic_assign(orig_type_left, expression->right);
8571         report_assign_error(error, orig_type_left, expression->right,
8572                         "assignment", &left->base.source_position);
8573         expression->right = create_implicit_cast(expression->right, orig_type_left);
8574         expression->base.type = orig_type_left;
8575 }
8576
8577 /**
8578  * Determine if the outermost operation (or parts thereof) of the given
8579  * expression has no effect in order to generate a warning about this fact.
8580  * Therefore in some cases this only examines some of the operands of the
8581  * expression (see comments in the function and examples below).
8582  * Examples:
8583  *   f() + 23;    // warning, because + has no effect
8584  *   x || f();    // no warning, because x controls execution of f()
8585  *   x ? y : f(); // warning, because y has no effect
8586  *   (void)x;     // no warning to be able to suppress the warning
8587  * This function can NOT be used for an "expression has definitely no effect"-
8588  * analysis. */
8589 static bool expression_has_effect(const expression_t *const expr)
8590 {
8591         switch (expr->kind) {
8592                 case EXPR_UNKNOWN:                   break;
8593                 case EXPR_INVALID:                   return true; /* do NOT warn */
8594                 case EXPR_REFERENCE:                 return false;
8595                 /* suppress the warning for microsoft __noop operations */
8596                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
8597                 case EXPR_CHARACTER_CONSTANT:        return false;
8598                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
8599                 case EXPR_STRING_LITERAL:            return false;
8600                 case EXPR_WIDE_STRING_LITERAL:       return false;
8601                 case EXPR_LABEL_ADDRESS:             return false;
8602
8603                 case EXPR_CALL: {
8604                         const call_expression_t *const call = &expr->call;
8605                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
8606                                 return true;
8607
8608                         switch (call->function->builtin_symbol.symbol->ID) {
8609                                 case T___builtin_va_end: return true;
8610                                 default:                 return false;
8611                         }
8612                 }
8613
8614                 /* Generate the warning if either the left or right hand side of a
8615                  * conditional expression has no effect */
8616                 case EXPR_CONDITIONAL: {
8617                         const conditional_expression_t *const cond = &expr->conditional;
8618                         return
8619                                 expression_has_effect(cond->true_expression) &&
8620                                 expression_has_effect(cond->false_expression);
8621                 }
8622
8623                 case EXPR_SELECT:                    return false;
8624                 case EXPR_ARRAY_ACCESS:              return false;
8625                 case EXPR_SIZEOF:                    return false;
8626                 case EXPR_CLASSIFY_TYPE:             return false;
8627                 case EXPR_ALIGNOF:                   return false;
8628
8629                 case EXPR_FUNCNAME:                  return false;
8630                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
8631                 case EXPR_BUILTIN_CONSTANT_P:        return false;
8632                 case EXPR_BUILTIN_PREFETCH:          return true;
8633                 case EXPR_OFFSETOF:                  return false;
8634                 case EXPR_VA_START:                  return true;
8635                 case EXPR_VA_ARG:                    return true;
8636                 case EXPR_STATEMENT:                 return true; // TODO
8637                 case EXPR_COMPOUND_LITERAL:          return false;
8638
8639                 case EXPR_UNARY_NEGATE:              return false;
8640                 case EXPR_UNARY_PLUS:                return false;
8641                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
8642                 case EXPR_UNARY_NOT:                 return false;
8643                 case EXPR_UNARY_DEREFERENCE:         return false;
8644                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
8645                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
8646                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
8647                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
8648                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
8649
8650                 /* Treat void casts as if they have an effect in order to being able to
8651                  * suppress the warning */
8652                 case EXPR_UNARY_CAST: {
8653                         type_t *const type = skip_typeref(expr->base.type);
8654                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
8655                 }
8656
8657                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
8658                 case EXPR_UNARY_ASSUME:              return true;
8659                 case EXPR_UNARY_THROW:               return true;
8660
8661                 case EXPR_BINARY_ADD:                return false;
8662                 case EXPR_BINARY_SUB:                return false;
8663                 case EXPR_BINARY_MUL:                return false;
8664                 case EXPR_BINARY_DIV:                return false;
8665                 case EXPR_BINARY_MOD:                return false;
8666                 case EXPR_BINARY_EQUAL:              return false;
8667                 case EXPR_BINARY_NOTEQUAL:           return false;
8668                 case EXPR_BINARY_LESS:               return false;
8669                 case EXPR_BINARY_LESSEQUAL:          return false;
8670                 case EXPR_BINARY_GREATER:            return false;
8671                 case EXPR_BINARY_GREATEREQUAL:       return false;
8672                 case EXPR_BINARY_BITWISE_AND:        return false;
8673                 case EXPR_BINARY_BITWISE_OR:         return false;
8674                 case EXPR_BINARY_BITWISE_XOR:        return false;
8675                 case EXPR_BINARY_SHIFTLEFT:          return false;
8676                 case EXPR_BINARY_SHIFTRIGHT:         return false;
8677                 case EXPR_BINARY_ASSIGN:             return true;
8678                 case EXPR_BINARY_MUL_ASSIGN:         return true;
8679                 case EXPR_BINARY_DIV_ASSIGN:         return true;
8680                 case EXPR_BINARY_MOD_ASSIGN:         return true;
8681                 case EXPR_BINARY_ADD_ASSIGN:         return true;
8682                 case EXPR_BINARY_SUB_ASSIGN:         return true;
8683                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
8684                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
8685                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
8686                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
8687                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
8688
8689                 /* Only examine the right hand side of && and ||, because the left hand
8690                  * side already has the effect of controlling the execution of the right
8691                  * hand side */
8692                 case EXPR_BINARY_LOGICAL_AND:
8693                 case EXPR_BINARY_LOGICAL_OR:
8694                 /* Only examine the right hand side of a comma expression, because the left
8695                  * hand side has a separate warning */
8696                 case EXPR_BINARY_COMMA:
8697                         return expression_has_effect(expr->binary.right);
8698
8699                 case EXPR_BINARY_BUILTIN_EXPECT:     return true;
8700                 case EXPR_BINARY_ISGREATER:          return false;
8701                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
8702                 case EXPR_BINARY_ISLESS:             return false;
8703                 case EXPR_BINARY_ISLESSEQUAL:        return false;
8704                 case EXPR_BINARY_ISLESSGREATER:      return false;
8705                 case EXPR_BINARY_ISUNORDERED:        return false;
8706         }
8707
8708         internal_errorf(HERE, "unexpected expression");
8709 }
8710
8711 static void semantic_comma(binary_expression_t *expression)
8712 {
8713         if (warning.unused_value) {
8714                 const expression_t *const left = expression->left;
8715                 if (!expression_has_effect(left)) {
8716                         warningf(&left->base.source_position,
8717                                  "left-hand operand of comma expression has no effect");
8718                 }
8719         }
8720         expression->base.type = expression->right->base.type;
8721 }
8722
8723 /**
8724  * @param prec_r precedence of the right operand
8725  */
8726 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, prec_r, sfunc) \
8727 static expression_t *parse_##binexpression_type(expression_t *left)          \
8728 {                                                                            \
8729         expression_t *binexpr = allocate_expression_zero(binexpression_type);    \
8730         binexpr->base.source_position = *HERE;                                   \
8731         binexpr->binary.left          = left;                                    \
8732         eat(token_type);                                                         \
8733                                                                              \
8734         expression_t *right = parse_sub_expression(prec_r);                      \
8735                                                                              \
8736         binexpr->binary.right = right;                                           \
8737         sfunc(&binexpr->binary);                                                 \
8738                                                                              \
8739         return binexpr;                                                          \
8740 }
8741
8742 CREATE_BINEXPR_PARSER('*',                    EXPR_BINARY_MUL,                PREC_CAST,           semantic_binexpr_arithmetic)
8743 CREATE_BINEXPR_PARSER('/',                    EXPR_BINARY_DIV,                PREC_CAST,           semantic_divmod_arithmetic)
8744 CREATE_BINEXPR_PARSER('%',                    EXPR_BINARY_MOD,                PREC_CAST,           semantic_divmod_arithmetic)
8745 CREATE_BINEXPR_PARSER('+',                    EXPR_BINARY_ADD,                PREC_MULTIPLICATIVE, semantic_add)
8746 CREATE_BINEXPR_PARSER('-',                    EXPR_BINARY_SUB,                PREC_MULTIPLICATIVE, semantic_sub)
8747 CREATE_BINEXPR_PARSER(T_LESSLESS,             EXPR_BINARY_SHIFTLEFT,          PREC_ADDITIVE,       semantic_shift_op)
8748 CREATE_BINEXPR_PARSER(T_GREATERGREATER,       EXPR_BINARY_SHIFTRIGHT,         PREC_ADDITIVE,       semantic_shift_op)
8749 CREATE_BINEXPR_PARSER('<',                    EXPR_BINARY_LESS,               PREC_SHIFT,          semantic_comparison)
8750 CREATE_BINEXPR_PARSER('>',                    EXPR_BINARY_GREATER,            PREC_SHIFT,          semantic_comparison)
8751 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,          PREC_SHIFT,          semantic_comparison)
8752 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,       PREC_SHIFT,          semantic_comparison)
8753 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,           PREC_RELATIONAL,     semantic_comparison)
8754 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,              PREC_RELATIONAL,     semantic_comparison)
8755 CREATE_BINEXPR_PARSER('&',                    EXPR_BINARY_BITWISE_AND,        PREC_EQUALITY,       semantic_binexpr_arithmetic)
8756 CREATE_BINEXPR_PARSER('^',                    EXPR_BINARY_BITWISE_XOR,        PREC_AND,            semantic_binexpr_arithmetic)
8757 CREATE_BINEXPR_PARSER('|',                    EXPR_BINARY_BITWISE_OR,         PREC_XOR,            semantic_binexpr_arithmetic)
8758 CREATE_BINEXPR_PARSER(T_ANDAND,               EXPR_BINARY_LOGICAL_AND,        PREC_OR,             semantic_logical_op)
8759 CREATE_BINEXPR_PARSER(T_PIPEPIPE,             EXPR_BINARY_LOGICAL_OR,         PREC_LOGICAL_AND,    semantic_logical_op)
8760 CREATE_BINEXPR_PARSER('=',                    EXPR_BINARY_ASSIGN,             PREC_ASSIGNMENT,     semantic_binexpr_assign)
8761 CREATE_BINEXPR_PARSER(T_PLUSEQUAL,            EXPR_BINARY_ADD_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
8762 CREATE_BINEXPR_PARSER(T_MINUSEQUAL,           EXPR_BINARY_SUB_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
8763 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL,        EXPR_BINARY_MUL_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_assign)
8764 CREATE_BINEXPR_PARSER(T_SLASHEQUAL,           EXPR_BINARY_DIV_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
8765 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL,         EXPR_BINARY_MOD_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
8766 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL,        EXPR_BINARY_SHIFTLEFT_ASSIGN,   PREC_ASSIGNMENT,     semantic_arithmetic_assign)
8767 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL,  EXPR_BINARY_SHIFTRIGHT_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
8768 CREATE_BINEXPR_PARSER(T_ANDEQUAL,             EXPR_BINARY_BITWISE_AND_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
8769 CREATE_BINEXPR_PARSER(T_PIPEEQUAL,            EXPR_BINARY_BITWISE_OR_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
8770 CREATE_BINEXPR_PARSER(T_CARETEQUAL,           EXPR_BINARY_BITWISE_XOR_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
8771 CREATE_BINEXPR_PARSER(',',                    EXPR_BINARY_COMMA,              PREC_ASSIGNMENT,     semantic_comma)
8772
8773
8774 static expression_t *parse_sub_expression(precedence_t precedence)
8775 {
8776         if (token.type < 0) {
8777                 return expected_expression_error();
8778         }
8779
8780         expression_parser_function_t *parser
8781                 = &expression_parsers[token.type];
8782         source_position_t             source_position = token.source_position;
8783         expression_t                 *left;
8784
8785         if (parser->parser != NULL) {
8786                 left = parser->parser();
8787         } else {
8788                 left = parse_primary_expression();
8789         }
8790         assert(left != NULL);
8791         left->base.source_position = source_position;
8792
8793         while(true) {
8794                 if (token.type < 0) {
8795                         return expected_expression_error();
8796                 }
8797
8798                 parser = &expression_parsers[token.type];
8799                 if (parser->infix_parser == NULL)
8800                         break;
8801                 if (parser->infix_precedence < precedence)
8802                         break;
8803
8804                 left = parser->infix_parser(left);
8805
8806                 assert(left != NULL);
8807                 assert(left->kind != EXPR_UNKNOWN);
8808                 left->base.source_position = source_position;
8809         }
8810
8811         return left;
8812 }
8813
8814 /**
8815  * Parse an expression.
8816  */
8817 static expression_t *parse_expression(void)
8818 {
8819         return parse_sub_expression(PREC_EXPRESSION);
8820 }
8821
8822 /**
8823  * Register a parser for a prefix-like operator.
8824  *
8825  * @param parser      the parser function
8826  * @param token_type  the token type of the prefix token
8827  */
8828 static void register_expression_parser(parse_expression_function parser,
8829                                        int token_type)
8830 {
8831         expression_parser_function_t *entry = &expression_parsers[token_type];
8832
8833         if (entry->parser != NULL) {
8834                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
8835                 panic("trying to register multiple expression parsers for a token");
8836         }
8837         entry->parser = parser;
8838 }
8839
8840 /**
8841  * Register a parser for an infix operator with given precedence.
8842  *
8843  * @param parser      the parser function
8844  * @param token_type  the token type of the infix operator
8845  * @param precedence  the precedence of the operator
8846  */
8847 static void register_infix_parser(parse_expression_infix_function parser,
8848                 int token_type, unsigned precedence)
8849 {
8850         expression_parser_function_t *entry = &expression_parsers[token_type];
8851
8852         if (entry->infix_parser != NULL) {
8853                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
8854                 panic("trying to register multiple infix expression parsers for a "
8855                       "token");
8856         }
8857         entry->infix_parser     = parser;
8858         entry->infix_precedence = precedence;
8859 }
8860
8861 /**
8862  * Initialize the expression parsers.
8863  */
8864 static void init_expression_parsers(void)
8865 {
8866         memset(&expression_parsers, 0, sizeof(expression_parsers));
8867
8868         register_infix_parser(parse_array_expression,               '[',                    PREC_POSTFIX);
8869         register_infix_parser(parse_call_expression,                '(',                    PREC_POSTFIX);
8870         register_infix_parser(parse_select_expression,              '.',                    PREC_POSTFIX);
8871         register_infix_parser(parse_select_expression,              T_MINUSGREATER,         PREC_POSTFIX);
8872         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,   T_PLUSPLUS,             PREC_POSTFIX);
8873         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,   T_MINUSMINUS,           PREC_POSTFIX);
8874         register_infix_parser(parse_EXPR_BINARY_MUL,                '*',                    PREC_MULTIPLICATIVE);
8875         register_infix_parser(parse_EXPR_BINARY_DIV,                '/',                    PREC_MULTIPLICATIVE);
8876         register_infix_parser(parse_EXPR_BINARY_MOD,                '%',                    PREC_MULTIPLICATIVE);
8877         register_infix_parser(parse_EXPR_BINARY_ADD,                '+',                    PREC_ADDITIVE);
8878         register_infix_parser(parse_EXPR_BINARY_SUB,                '-',                    PREC_ADDITIVE);
8879         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,          T_LESSLESS,             PREC_SHIFT);
8880         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,         T_GREATERGREATER,       PREC_SHIFT);
8881         register_infix_parser(parse_EXPR_BINARY_LESS,               '<',                    PREC_RELATIONAL);
8882         register_infix_parser(parse_EXPR_BINARY_GREATER,            '>',                    PREC_RELATIONAL);
8883         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,          T_LESSEQUAL,            PREC_RELATIONAL);
8884         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL,       T_GREATEREQUAL,         PREC_RELATIONAL);
8885         register_infix_parser(parse_EXPR_BINARY_EQUAL,              T_EQUALEQUAL,           PREC_EQUALITY);
8886         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,           T_EXCLAMATIONMARKEQUAL, PREC_EQUALITY);
8887         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,        '&',                    PREC_AND);
8888         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,        '^',                    PREC_XOR);
8889         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,         '|',                    PREC_OR);
8890         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,        T_ANDAND,               PREC_LOGICAL_AND);
8891         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,         T_PIPEPIPE,             PREC_LOGICAL_OR);
8892         register_infix_parser(parse_conditional_expression,         '?',                    PREC_CONDITIONAL);
8893         register_infix_parser(parse_EXPR_BINARY_ASSIGN,             '=',                    PREC_ASSIGNMENT);
8894         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,         T_PLUSEQUAL,            PREC_ASSIGNMENT);
8895         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,         T_MINUSEQUAL,           PREC_ASSIGNMENT);
8896         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,         T_ASTERISKEQUAL,        PREC_ASSIGNMENT);
8897         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,         T_SLASHEQUAL,           PREC_ASSIGNMENT);
8898         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,         T_PERCENTEQUAL,         PREC_ASSIGNMENT);
8899         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,   T_LESSLESSEQUAL,        PREC_ASSIGNMENT);
8900         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,  T_GREATERGREATEREQUAL,  PREC_ASSIGNMENT);
8901         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN, T_ANDEQUAL,             PREC_ASSIGNMENT);
8902         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,  T_PIPEEQUAL,            PREC_ASSIGNMENT);
8903         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN, T_CARETEQUAL,           PREC_ASSIGNMENT);
8904         register_infix_parser(parse_EXPR_BINARY_COMMA,              ',',                    PREC_EXPRESSION);
8905
8906         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-');
8907         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+');
8908         register_expression_parser(parse_EXPR_UNARY_NOT,              '!');
8909         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~');
8910         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*');
8911         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&');
8912         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT, T_PLUSPLUS);
8913         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT, T_MINUSMINUS);
8914         register_expression_parser(parse_sizeof,                      T_sizeof);
8915         register_expression_parser(parse_alignof,                     T___alignof__);
8916         register_expression_parser(parse_extension,                   T___extension__);
8917         register_expression_parser(parse_builtin_classify_type,       T___builtin_classify_type);
8918         register_expression_parser(parse_throw,                       T_throw);
8919 }
8920
8921 /**
8922  * Parse a asm statement arguments specification.
8923  */
8924 static asm_argument_t *parse_asm_arguments(bool is_out)
8925 {
8926         asm_argument_t *result = NULL;
8927         asm_argument_t *last   = NULL;
8928
8929         while (token.type == T_STRING_LITERAL || token.type == '[') {
8930                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
8931                 memset(argument, 0, sizeof(argument[0]));
8932
8933                 if (token.type == '[') {
8934                         eat('[');
8935                         if (token.type != T_IDENTIFIER) {
8936                                 parse_error_expected("while parsing asm argument",
8937                                                      T_IDENTIFIER, NULL);
8938                                 return NULL;
8939                         }
8940                         argument->symbol = token.v.symbol;
8941
8942                         expect(']');
8943                 }
8944
8945                 argument->constraints = parse_string_literals();
8946                 expect('(');
8947                 add_anchor_token(')');
8948                 expression_t *expression = parse_expression();
8949                 rem_anchor_token(')');
8950                 if (is_out) {
8951                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
8952                          * change size or type representation (e.g. int -> long is ok, but
8953                          * int -> float is not) */
8954                         if (expression->kind == EXPR_UNARY_CAST) {
8955                                 type_t      *const type = expression->base.type;
8956                                 type_kind_t  const kind = type->kind;
8957                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
8958                                         unsigned flags;
8959                                         unsigned size;
8960                                         if (kind == TYPE_ATOMIC) {
8961                                                 atomic_type_kind_t const akind = type->atomic.akind;
8962                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8963                                                 size  = get_atomic_type_size(akind);
8964                                         } else {
8965                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8966                                                 size  = get_atomic_type_size(get_intptr_kind());
8967                                         }
8968
8969                                         do {
8970                                                 expression_t *const value      = expression->unary.value;
8971                                                 type_t       *const value_type = value->base.type;
8972                                                 type_kind_t   const value_kind = value_type->kind;
8973
8974                                                 unsigned value_flags;
8975                                                 unsigned value_size;
8976                                                 if (value_kind == TYPE_ATOMIC) {
8977                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
8978                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8979                                                         value_size  = get_atomic_type_size(value_akind);
8980                                                 } else if (value_kind == TYPE_POINTER) {
8981                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8982                                                         value_size  = get_atomic_type_size(get_intptr_kind());
8983                                                 } else {
8984                                                         break;
8985                                                 }
8986
8987                                                 if (value_flags != flags || value_size != size)
8988                                                         break;
8989
8990                                                 expression = value;
8991                                         } while (expression->kind == EXPR_UNARY_CAST);
8992                                 }
8993                         }
8994
8995                         if (!is_lvalue(expression)) {
8996                                 errorf(&expression->base.source_position,
8997                                        "asm output argument is not an lvalue");
8998                         }
8999
9000                         if (argument->constraints.begin[0] == '+')
9001                                 mark_decls_read(expression, NULL);
9002                 } else {
9003                         mark_decls_read(expression, NULL);
9004                 }
9005                 argument->expression = expression;
9006                 expect(')');
9007
9008                 set_address_taken(expression, true);
9009
9010                 if (last != NULL) {
9011                         last->next = argument;
9012                 } else {
9013                         result = argument;
9014                 }
9015                 last = argument;
9016
9017                 if (token.type != ',')
9018                         break;
9019                 eat(',');
9020         }
9021
9022         return result;
9023 end_error:
9024         return NULL;
9025 }
9026
9027 /**
9028  * Parse a asm statement clobber specification.
9029  */
9030 static asm_clobber_t *parse_asm_clobbers(void)
9031 {
9032         asm_clobber_t *result = NULL;
9033         asm_clobber_t *last   = NULL;
9034
9035         while(token.type == T_STRING_LITERAL) {
9036                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
9037                 clobber->clobber       = parse_string_literals();
9038
9039                 if (last != NULL) {
9040                         last->next = clobber;
9041                 } else {
9042                         result = clobber;
9043                 }
9044                 last = clobber;
9045
9046                 if (token.type != ',')
9047                         break;
9048                 eat(',');
9049         }
9050
9051         return result;
9052 }
9053
9054 /**
9055  * Parse an asm statement.
9056  */
9057 static statement_t *parse_asm_statement(void)
9058 {
9059         statement_t     *statement     = allocate_statement_zero(STATEMENT_ASM);
9060         asm_statement_t *asm_statement = &statement->asms;
9061
9062         eat(T_asm);
9063
9064         if (token.type == T_volatile) {
9065                 next_token();
9066                 asm_statement->is_volatile = true;
9067         }
9068
9069         expect('(');
9070         add_anchor_token(')');
9071         add_anchor_token(':');
9072         asm_statement->asm_text = parse_string_literals();
9073
9074         if (token.type != ':') {
9075                 rem_anchor_token(':');
9076                 goto end_of_asm;
9077         }
9078         eat(':');
9079
9080         asm_statement->outputs = parse_asm_arguments(true);
9081         if (token.type != ':') {
9082                 rem_anchor_token(':');
9083                 goto end_of_asm;
9084         }
9085         eat(':');
9086
9087         asm_statement->inputs = parse_asm_arguments(false);
9088         if (token.type != ':') {
9089                 rem_anchor_token(':');
9090                 goto end_of_asm;
9091         }
9092         rem_anchor_token(':');
9093         eat(':');
9094
9095         asm_statement->clobbers = parse_asm_clobbers();
9096
9097 end_of_asm:
9098         rem_anchor_token(')');
9099         expect(')');
9100         expect(';');
9101
9102         if (asm_statement->outputs == NULL) {
9103                 /* GCC: An 'asm' instruction without any output operands will be treated
9104                  * identically to a volatile 'asm' instruction. */
9105                 asm_statement->is_volatile = true;
9106         }
9107
9108         return statement;
9109 end_error:
9110         return create_invalid_statement();
9111 }
9112
9113 /**
9114  * Parse a case statement.
9115  */
9116 static statement_t *parse_case_statement(void)
9117 {
9118         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9119         source_position_t *const pos       = &statement->base.source_position;
9120
9121         eat(T_case);
9122
9123         expression_t *const expression   = parse_expression();
9124         statement->case_label.expression = expression;
9125         if (!is_constant_expression(expression)) {
9126                 /* This check does not prevent the error message in all cases of an
9127                  * prior error while parsing the expression.  At least it catches the
9128                  * common case of a mistyped enum entry. */
9129                 if (is_type_valid(skip_typeref(expression->base.type))) {
9130                         errorf(pos, "case label does not reduce to an integer constant");
9131                 }
9132                 statement->case_label.is_bad = true;
9133         } else {
9134                 long const val = fold_constant(expression);
9135                 statement->case_label.first_case = val;
9136                 statement->case_label.last_case  = val;
9137         }
9138
9139         if (GNU_MODE) {
9140                 if (token.type == T_DOTDOTDOT) {
9141                         next_token();
9142                         expression_t *const end_range   = parse_expression();
9143                         statement->case_label.end_range = end_range;
9144                         if (!is_constant_expression(end_range)) {
9145                                 /* This check does not prevent the error message in all cases of an
9146                                  * prior error while parsing the expression.  At least it catches the
9147                                  * common case of a mistyped enum entry. */
9148                                 if (is_type_valid(skip_typeref(end_range->base.type))) {
9149                                         errorf(pos, "case range does not reduce to an integer constant");
9150                                 }
9151                                 statement->case_label.is_bad = true;
9152                         } else {
9153                                 long const val = fold_constant(end_range);
9154                                 statement->case_label.last_case = val;
9155
9156                                 if (warning.other && val < statement->case_label.first_case) {
9157                                         statement->case_label.is_empty_range = true;
9158                                         warningf(pos, "empty range specified");
9159                                 }
9160                         }
9161                 }
9162         }
9163
9164         PUSH_PARENT(statement);
9165
9166         expect(':');
9167
9168         if (current_switch != NULL) {
9169                 if (! statement->case_label.is_bad) {
9170                         /* Check for duplicate case values */
9171                         case_label_statement_t *c = &statement->case_label;
9172                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
9173                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
9174                                         continue;
9175
9176                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
9177                                         continue;
9178
9179                                 errorf(pos, "duplicate case value (previously used %P)",
9180                                        &l->base.source_position);
9181                                 break;
9182                         }
9183                 }
9184                 /* link all cases into the switch statement */
9185                 if (current_switch->last_case == NULL) {
9186                         current_switch->first_case      = &statement->case_label;
9187                 } else {
9188                         current_switch->last_case->next = &statement->case_label;
9189                 }
9190                 current_switch->last_case = &statement->case_label;
9191         } else {
9192                 errorf(pos, "case label not within a switch statement");
9193         }
9194
9195         statement_t *const inner_stmt = parse_statement();
9196         statement->case_label.statement = inner_stmt;
9197         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9198                 errorf(&inner_stmt->base.source_position, "declaration after case label");
9199         }
9200
9201         POP_PARENT;
9202         return statement;
9203 end_error:
9204         POP_PARENT;
9205         return create_invalid_statement();
9206 }
9207
9208 /**
9209  * Parse a default statement.
9210  */
9211 static statement_t *parse_default_statement(void)
9212 {
9213         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9214
9215         eat(T_default);
9216
9217         PUSH_PARENT(statement);
9218
9219         expect(':');
9220         if (current_switch != NULL) {
9221                 const case_label_statement_t *def_label = current_switch->default_label;
9222                 if (def_label != NULL) {
9223                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
9224                                &def_label->base.source_position);
9225                 } else {
9226                         current_switch->default_label = &statement->case_label;
9227
9228                         /* link all cases into the switch statement */
9229                         if (current_switch->last_case == NULL) {
9230                                 current_switch->first_case      = &statement->case_label;
9231                         } else {
9232                                 current_switch->last_case->next = &statement->case_label;
9233                         }
9234                         current_switch->last_case = &statement->case_label;
9235                 }
9236         } else {
9237                 errorf(&statement->base.source_position,
9238                         "'default' label not within a switch statement");
9239         }
9240
9241         statement_t *const inner_stmt = parse_statement();
9242         statement->case_label.statement = inner_stmt;
9243         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9244                 errorf(&inner_stmt->base.source_position, "declaration after default label");
9245         }
9246
9247         POP_PARENT;
9248         return statement;
9249 end_error:
9250         POP_PARENT;
9251         return create_invalid_statement();
9252 }
9253
9254 /**
9255  * Parse a label statement.
9256  */
9257 static statement_t *parse_label_statement(void)
9258 {
9259         assert(token.type == T_IDENTIFIER);
9260         symbol_t      *symbol = token.v.symbol;
9261         declaration_t *label  = get_label(symbol);
9262
9263         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
9264         statement->label.label       = label;
9265
9266         next_token();
9267
9268         PUSH_PARENT(statement);
9269
9270         /* if statement is already set then the label is defined twice,
9271          * otherwise it was just mentioned in a goto/local label declaration so far */
9272         if (label->init.statement != NULL) {
9273                 errorf(HERE, "duplicate label '%Y' (declared %P)",
9274                        symbol, &label->source_position);
9275         } else {
9276                 label->source_position = token.source_position;
9277                 label->init.statement  = statement;
9278         }
9279
9280         eat(':');
9281
9282         if (token.type == '}') {
9283                 /* TODO only warn? */
9284                 if (warning.other && false) {
9285                         warningf(HERE, "label at end of compound statement");
9286                         statement->label.statement = create_empty_statement();
9287                 } else {
9288                         errorf(HERE, "label at end of compound statement");
9289                         statement->label.statement = create_invalid_statement();
9290                 }
9291         } else if (token.type == ';') {
9292                 /* Eat an empty statement here, to avoid the warning about an empty
9293                  * statement after a label.  label:; is commonly used to have a label
9294                  * before a closing brace. */
9295                 statement->label.statement = create_empty_statement();
9296                 next_token();
9297         } else {
9298                 statement_t *const inner_stmt = parse_statement();
9299                 statement->label.statement = inner_stmt;
9300                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
9301                         errorf(&inner_stmt->base.source_position, "declaration after label");
9302                 }
9303         }
9304
9305         /* remember the labels in a list for later checking */
9306         if (label_last == NULL) {
9307                 label_first = &statement->label;
9308         } else {
9309                 label_last->next = &statement->label;
9310         }
9311         label_last = &statement->label;
9312
9313         POP_PARENT;
9314         return statement;
9315 }
9316
9317 /**
9318  * Parse an if statement.
9319  */
9320 static statement_t *parse_if(void)
9321 {
9322         statement_t *statement = allocate_statement_zero(STATEMENT_IF);
9323
9324         eat(T_if);
9325
9326         PUSH_PARENT(statement);
9327
9328         add_anchor_token('{');
9329
9330         expect('(');
9331         add_anchor_token(')');
9332         expression_t *const expr = parse_expression();
9333         statement->ifs.condition = expr;
9334         mark_decls_read(expr, NULL);
9335         rem_anchor_token(')');
9336         expect(')');
9337
9338 end_error:
9339         rem_anchor_token('{');
9340
9341         add_anchor_token(T_else);
9342         statement->ifs.true_statement = parse_statement();
9343         rem_anchor_token(T_else);
9344
9345         if (token.type == T_else) {
9346                 next_token();
9347                 statement->ifs.false_statement = parse_statement();
9348         }
9349
9350         POP_PARENT;
9351         return statement;
9352 }
9353
9354 /**
9355  * Check that all enums are handled in a switch.
9356  *
9357  * @param statement  the switch statement to check
9358  */
9359 static void check_enum_cases(const switch_statement_t *statement) {
9360         const type_t *type = skip_typeref(statement->expression->base.type);
9361         if (! is_type_enum(type))
9362                 return;
9363         const enum_type_t *enumt = &type->enumt;
9364
9365         /* if we have a default, no warnings */
9366         if (statement->default_label != NULL)
9367                 return;
9368
9369         /* FIXME: calculation of value should be done while parsing */
9370         const declaration_t *declaration;
9371         long last_value = -1;
9372         for (declaration = enumt->declaration->next;
9373              declaration != NULL && declaration->storage_class == STORAGE_CLASS_ENUM_ENTRY;
9374                  declaration = declaration->next) {
9375                 const expression_t *expression = declaration->init.enum_value;
9376                 long                value      = expression != NULL ? fold_constant(expression) : last_value + 1;
9377                 bool                found      = false;
9378                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
9379                         if (l->expression == NULL)
9380                                 continue;
9381                         if (l->first_case <= value && value <= l->last_case) {
9382                                 found = true;
9383                                 break;
9384                         }
9385                 }
9386                 if (! found) {
9387                         warningf(&statement->base.source_position,
9388                                 "enumeration value '%Y' not handled in switch", declaration->symbol);
9389                 }
9390                 last_value = value;
9391         }
9392 }
9393
9394 /**
9395  * Parse a switch statement.
9396  */
9397 static statement_t *parse_switch(void)
9398 {
9399         statement_t *statement = allocate_statement_zero(STATEMENT_SWITCH);
9400
9401         eat(T_switch);
9402
9403         PUSH_PARENT(statement);
9404
9405         expect('(');
9406         add_anchor_token(')');
9407         expression_t *const expr = parse_expression();
9408         mark_decls_read(expr, NULL);
9409         type_t       *      type = skip_typeref(expr->base.type);
9410         if (is_type_integer(type)) {
9411                 type = promote_integer(type);
9412                 if (warning.traditional) {
9413                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
9414                                 warningf(&expr->base.source_position,
9415                                         "'%T' switch expression not converted to '%T' in ISO C",
9416                                         type, type_int);
9417                         }
9418                 }
9419         } else if (is_type_valid(type)) {
9420                 errorf(&expr->base.source_position,
9421                        "switch quantity is not an integer, but '%T'", type);
9422                 type = type_error_type;
9423         }
9424         statement->switchs.expression = create_implicit_cast(expr, type);
9425         expect(')');
9426         rem_anchor_token(')');
9427
9428         switch_statement_t *rem = current_switch;
9429         current_switch          = &statement->switchs;
9430         statement->switchs.body = parse_statement();
9431         current_switch          = rem;
9432
9433         if (warning.switch_default &&
9434             statement->switchs.default_label == NULL) {
9435                 warningf(&statement->base.source_position, "switch has no default case");
9436         }
9437         if (warning.switch_enum)
9438                 check_enum_cases(&statement->switchs);
9439
9440         POP_PARENT;
9441         return statement;
9442 end_error:
9443         POP_PARENT;
9444         return create_invalid_statement();
9445 }
9446
9447 static statement_t *parse_loop_body(statement_t *const loop)
9448 {
9449         statement_t *const rem = current_loop;
9450         current_loop = loop;
9451
9452         statement_t *const body = parse_statement();
9453
9454         current_loop = rem;
9455         return body;
9456 }
9457
9458 /**
9459  * Parse a while statement.
9460  */
9461 static statement_t *parse_while(void)
9462 {
9463         statement_t *statement = allocate_statement_zero(STATEMENT_WHILE);
9464
9465         eat(T_while);
9466
9467         PUSH_PARENT(statement);
9468
9469         expect('(');
9470         add_anchor_token(')');
9471         expression_t *const cond = parse_expression();
9472         statement->whiles.condition = cond;
9473         mark_decls_read(cond, NULL);
9474         rem_anchor_token(')');
9475         expect(')');
9476
9477         statement->whiles.body = parse_loop_body(statement);
9478
9479         POP_PARENT;
9480         return statement;
9481 end_error:
9482         POP_PARENT;
9483         return create_invalid_statement();
9484 }
9485
9486 /**
9487  * Parse a do statement.
9488  */
9489 static statement_t *parse_do(void)
9490 {
9491         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
9492
9493         eat(T_do);
9494
9495         PUSH_PARENT(statement);
9496
9497         add_anchor_token(T_while);
9498         statement->do_while.body = parse_loop_body(statement);
9499         rem_anchor_token(T_while);
9500
9501         expect(T_while);
9502         expect('(');
9503         add_anchor_token(')');
9504         expression_t *const cond = parse_expression();
9505         statement->do_while.condition = cond;
9506         mark_decls_read(cond, NULL);
9507         rem_anchor_token(')');
9508         expect(')');
9509         expect(';');
9510
9511         POP_PARENT;
9512         return statement;
9513 end_error:
9514         POP_PARENT;
9515         return create_invalid_statement();
9516 }
9517
9518 /**
9519  * Parse a for statement.
9520  */
9521 static statement_t *parse_for(void)
9522 {
9523         statement_t *statement = allocate_statement_zero(STATEMENT_FOR);
9524
9525         eat(T_for);
9526
9527         PUSH_PARENT(statement);
9528
9529         size_t const top = environment_top();
9530         scope_push(&statement->fors.scope);
9531
9532         expect('(');
9533         add_anchor_token(')');
9534
9535         if (token.type != ';') {
9536                 if (is_declaration_specifier(&token, false)) {
9537                         parse_declaration(record_declaration);
9538                 } else {
9539                         add_anchor_token(';');
9540                         expression_t *const init = parse_expression();
9541                         statement->fors.initialisation = init;
9542                         mark_decls_read(init, DECL_ANY);
9543                         if (warning.unused_value && !expression_has_effect(init)) {
9544                                 warningf(&init->base.source_position,
9545                                          "initialisation of 'for'-statement has no effect");
9546                         }
9547                         rem_anchor_token(';');
9548                         expect(';');
9549                 }
9550         } else {
9551                 expect(';');
9552         }
9553
9554         if (token.type != ';') {
9555                 add_anchor_token(';');
9556                 expression_t *const cond = parse_expression();
9557                 statement->fors.condition = cond;
9558                 mark_decls_read(cond, NULL);
9559                 rem_anchor_token(';');
9560         }
9561         expect(';');
9562         if (token.type != ')') {
9563                 expression_t *const step = parse_expression();
9564                 statement->fors.step = step;
9565                 mark_decls_read(step, DECL_ANY);
9566                 if (warning.unused_value && !expression_has_effect(step)) {
9567                         warningf(&step->base.source_position,
9568                                  "step of 'for'-statement has no effect");
9569                 }
9570         }
9571         rem_anchor_token(')');
9572         expect(')');
9573         statement->fors.body = parse_loop_body(statement);
9574
9575         assert(scope == &statement->fors.scope);
9576         scope_pop();
9577         environment_pop_to(top);
9578
9579         POP_PARENT;
9580         return statement;
9581
9582 end_error:
9583         POP_PARENT;
9584         rem_anchor_token(')');
9585         assert(scope == &statement->fors.scope);
9586         scope_pop();
9587         environment_pop_to(top);
9588
9589         return create_invalid_statement();
9590 }
9591
9592 /**
9593  * Parse a goto statement.
9594  */
9595 static statement_t *parse_goto(void)
9596 {
9597         statement_t *statement = allocate_statement_zero(STATEMENT_GOTO);
9598         eat(T_goto);
9599
9600         if (GNU_MODE && token.type == '*') {
9601                 next_token();
9602                 expression_t *expression = parse_expression();
9603                 mark_decls_read(expression, NULL);
9604
9605                 /* Argh: although documentation say the expression must be of type void *,
9606                  * gcc excepts anything that can be casted into void * without error */
9607                 type_t *type = expression->base.type;
9608
9609                 if (type != type_error_type) {
9610                         if (!is_type_pointer(type) && !is_type_integer(type)) {
9611                                 errorf(&expression->base.source_position,
9612                                         "cannot convert to a pointer type");
9613                         } else if (warning.other && type != type_void_ptr) {
9614                                 warningf(&expression->base.source_position,
9615                                         "type of computed goto expression should be 'void*' not '%T'", type);
9616                         }
9617                         expression = create_implicit_cast(expression, type_void_ptr);
9618                 }
9619
9620                 statement->gotos.expression = expression;
9621         } else {
9622                 if (token.type != T_IDENTIFIER) {
9623                         if (GNU_MODE)
9624                                 parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
9625                         else
9626                                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
9627                         eat_until_anchor();
9628                         goto end_error;
9629                 }
9630                 symbol_t *symbol = token.v.symbol;
9631                 next_token();
9632
9633                 statement->gotos.label = get_label(symbol);
9634         }
9635
9636         /* remember the goto's in a list for later checking */
9637         if (goto_last == NULL) {
9638                 goto_first = &statement->gotos;
9639         } else {
9640                 goto_last->next = &statement->gotos;
9641         }
9642         goto_last = &statement->gotos;
9643
9644         expect(';');
9645
9646         return statement;
9647 end_error:
9648         return create_invalid_statement();
9649 }
9650
9651 /**
9652  * Parse a continue statement.
9653  */
9654 static statement_t *parse_continue(void)
9655 {
9656         if (current_loop == NULL) {
9657                 errorf(HERE, "continue statement not within loop");
9658         }
9659
9660         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
9661
9662         eat(T_continue);
9663         expect(';');
9664
9665 end_error:
9666         return statement;
9667 }
9668
9669 /**
9670  * Parse a break statement.
9671  */
9672 static statement_t *parse_break(void)
9673 {
9674         if (current_switch == NULL && current_loop == NULL) {
9675                 errorf(HERE, "break statement not within loop or switch");
9676         }
9677
9678         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
9679
9680         eat(T_break);
9681         expect(';');
9682
9683 end_error:
9684         return statement;
9685 }
9686
9687 /**
9688  * Parse a __leave statement.
9689  */
9690 static statement_t *parse_leave_statement(void)
9691 {
9692         if (current_try == NULL) {
9693                 errorf(HERE, "__leave statement not within __try");
9694         }
9695
9696         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
9697
9698         eat(T___leave);
9699         expect(';');
9700
9701 end_error:
9702         return statement;
9703 }
9704
9705 /**
9706  * Check if a given declaration represents a local variable.
9707  */
9708 static bool is_local_var_declaration(const declaration_t *declaration)
9709 {
9710         switch ((storage_class_tag_t) declaration->storage_class) {
9711         case STORAGE_CLASS_AUTO:
9712         case STORAGE_CLASS_REGISTER: {
9713                 const type_t *type = skip_typeref(declaration->type);
9714                 if (is_type_function(type)) {
9715                         return false;
9716                 } else {
9717                         return true;
9718                 }
9719         }
9720         default:
9721                 return false;
9722         }
9723 }
9724
9725 /**
9726  * Check if a given declaration represents a variable.
9727  */
9728 static bool is_var_declaration(const declaration_t *declaration)
9729 {
9730         if (declaration->storage_class == STORAGE_CLASS_TYPEDEF)
9731                 return false;
9732
9733         const type_t *type = skip_typeref(declaration->type);
9734         return !is_type_function(type);
9735 }
9736
9737 /**
9738  * Check if a given expression represents a local variable.
9739  */
9740 static bool is_local_variable(const expression_t *expression)
9741 {
9742         if (expression->base.kind != EXPR_REFERENCE) {
9743                 return false;
9744         }
9745         const declaration_t *declaration = expression->reference.declaration;
9746         return is_local_var_declaration(declaration);
9747 }
9748
9749 /**
9750  * Check if a given expression represents a local variable and
9751  * return its declaration then, else return NULL.
9752  */
9753 declaration_t *expr_is_variable(const expression_t *expression)
9754 {
9755         if (expression->base.kind != EXPR_REFERENCE) {
9756                 return NULL;
9757         }
9758         declaration_t *declaration = expression->reference.declaration;
9759         if (is_var_declaration(declaration))
9760                 return declaration;
9761         return NULL;
9762 }
9763
9764 /**
9765  * Parse a return statement.
9766  */
9767 static statement_t *parse_return(void)
9768 {
9769         eat(T_return);
9770
9771         statement_t *statement = allocate_statement_zero(STATEMENT_RETURN);
9772
9773         expression_t *return_value = NULL;
9774         if (token.type != ';') {
9775                 return_value = parse_expression();
9776                 mark_decls_read(return_value, NULL);
9777         }
9778
9779         const type_t *const func_type = current_function->type;
9780         assert(is_type_function(func_type));
9781         type_t *const return_type = skip_typeref(func_type->function.return_type);
9782
9783         if (return_value != NULL) {
9784                 type_t *return_value_type = skip_typeref(return_value->base.type);
9785
9786                 if (is_type_atomic(return_type,        ATOMIC_TYPE_VOID) &&
9787                                 !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
9788                         if (warning.other) {
9789                                 warningf(&statement->base.source_position,
9790                                                 "'return' with a value, in function returning void");
9791                         }
9792                         return_value = NULL;
9793                 } else {
9794                         assign_error_t error = semantic_assign(return_type, return_value);
9795                         report_assign_error(error, return_type, return_value, "'return'",
9796                                             &statement->base.source_position);
9797                         return_value = create_implicit_cast(return_value, return_type);
9798                 }
9799                 /* check for returning address of a local var */
9800                 if (warning.other        &&
9801                                 return_value != NULL &&
9802                                 return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
9803                         const expression_t *expression = return_value->unary.value;
9804                         if (is_local_variable(expression)) {
9805                                 warningf(&statement->base.source_position,
9806                                          "function returns address of local variable");
9807                         }
9808                 }
9809         } else if (warning.other && !is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
9810                 warningf(&statement->base.source_position,
9811                                 "'return' without value, in function returning non-void");
9812         }
9813         statement->returns.value = return_value;
9814
9815         expect(';');
9816
9817 end_error:
9818         return statement;
9819 }
9820
9821 /**
9822  * Parse a declaration statement.
9823  */
9824 static statement_t *parse_declaration_statement(void)
9825 {
9826         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
9827
9828         declaration_t *before = last_declaration;
9829         if (GNU_MODE)
9830                 parse_external_declaration();
9831         else
9832                 parse_declaration(record_declaration);
9833
9834         if (before == NULL) {
9835                 statement->declaration.declarations_begin = scope->declarations;
9836         } else {
9837                 statement->declaration.declarations_begin = before->next;
9838         }
9839         statement->declaration.declarations_end = last_declaration;
9840
9841         return statement;
9842 }
9843
9844 /**
9845  * Parse an expression statement, ie. expr ';'.
9846  */
9847 static statement_t *parse_expression_statement(void)
9848 {
9849         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
9850
9851         expression_t *const expr         = parse_expression();
9852         statement->expression.expression = expr;
9853         mark_decls_read(expr, DECL_ANY);
9854
9855         expect(';');
9856
9857 end_error:
9858         return statement;
9859 }
9860
9861 /**
9862  * Parse a microsoft __try { } __finally { } or
9863  * __try{ } __except() { }
9864  */
9865 static statement_t *parse_ms_try_statment(void)
9866 {
9867         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
9868         eat(T___try);
9869
9870         PUSH_PARENT(statement);
9871
9872         ms_try_statement_t *rem = current_try;
9873         current_try = &statement->ms_try;
9874         statement->ms_try.try_statement = parse_compound_statement(false);
9875         current_try = rem;
9876
9877         POP_PARENT;
9878
9879         if (token.type == T___except) {
9880                 eat(T___except);
9881                 expect('(');
9882                 add_anchor_token(')');
9883                 expression_t *const expr = parse_expression();
9884                 mark_decls_read(expr, NULL);
9885                 type_t       *      type = skip_typeref(expr->base.type);
9886                 if (is_type_integer(type)) {
9887                         type = promote_integer(type);
9888                 } else if (is_type_valid(type)) {
9889                         errorf(&expr->base.source_position,
9890                                "__expect expression is not an integer, but '%T'", type);
9891                         type = type_error_type;
9892                 }
9893                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
9894                 rem_anchor_token(')');
9895                 expect(')');
9896                 statement->ms_try.final_statement = parse_compound_statement(false);
9897         } else if (token.type == T__finally) {
9898                 eat(T___finally);
9899                 statement->ms_try.final_statement = parse_compound_statement(false);
9900         } else {
9901                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
9902                 return create_invalid_statement();
9903         }
9904         return statement;
9905 end_error:
9906         return create_invalid_statement();
9907 }
9908
9909 static statement_t *parse_empty_statement(void)
9910 {
9911         if (warning.empty_statement) {
9912                 warningf(HERE, "statement is empty");
9913         }
9914         statement_t *const statement = create_empty_statement();
9915         eat(';');
9916         return statement;
9917 }
9918
9919 static statement_t *parse_local_label_declaration(void) {
9920         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
9921
9922         eat(T___label__);
9923
9924         declaration_t *begin = NULL, *end = NULL;
9925
9926         while (true) {
9927                 if (token.type != T_IDENTIFIER) {
9928                         parse_error_expected("while parsing local label declaration",
9929                                 T_IDENTIFIER, NULL);
9930                         goto end_error;
9931                 }
9932                 symbol_t      *symbol      = token.v.symbol;
9933                 declaration_t *declaration = get_declaration(symbol, NAMESPACE_LOCAL_LABEL);
9934                 if (declaration != NULL) {
9935                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition at %P)",
9936                                 symbol, &declaration->source_position);
9937                 } else {
9938                         declaration = allocate_declaration_zero();
9939                         declaration->namespc         = NAMESPACE_LOCAL_LABEL;
9940                         declaration->source_position = token.source_position;
9941                         declaration->symbol          = symbol;
9942                         declaration->parent_scope    = scope;
9943                         declaration->init.statement  = NULL;
9944
9945                         if (end != NULL)
9946                                 end->next = declaration;
9947                         end = declaration;
9948                         if (begin == NULL)
9949                                 begin = declaration;
9950
9951                         local_label_push(declaration);
9952                 }
9953                 next_token();
9954
9955                 if (token.type != ',')
9956                         break;
9957                 next_token();
9958         }
9959         eat(';');
9960 end_error:
9961         statement->declaration.declarations_begin = begin;
9962         statement->declaration.declarations_end   = end;
9963         return statement;
9964 }
9965
9966 /**
9967  * Parse a statement.
9968  * There's also parse_statement() which additionally checks for
9969  * "statement has no effect" warnings
9970  */
9971 static statement_t *intern_parse_statement(void)
9972 {
9973         statement_t *statement = NULL;
9974
9975         /* declaration or statement */
9976         add_anchor_token(';');
9977         switch (token.type) {
9978         case T_IDENTIFIER: {
9979                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
9980                 if (la1_type == ':') {
9981                         statement = parse_label_statement();
9982                 } else if (is_typedef_symbol(token.v.symbol)) {
9983                         statement = parse_declaration_statement();
9984                 } else switch (la1_type) {
9985                         case '*':
9986                                 if (get_declaration(token.v.symbol, NAMESPACE_NORMAL) != NULL)
9987                                         goto expression_statment;
9988                                 /* FALLTHROUGH */
9989
9990                         DECLARATION_START
9991                         case T_IDENTIFIER:
9992                                 statement = parse_declaration_statement();
9993                                 break;
9994
9995                         default:
9996 expression_statment:
9997                                 statement = parse_expression_statement();
9998                                 break;
9999                 }
10000                 break;
10001         }
10002
10003         case T___extension__:
10004                 /* This can be a prefix to a declaration or an expression statement.
10005                  * We simply eat it now and parse the rest with tail recursion. */
10006                 do {
10007                         next_token();
10008                 } while (token.type == T___extension__);
10009                 bool old_gcc_extension = in_gcc_extension;
10010                 in_gcc_extension       = true;
10011                 statement = parse_statement();
10012                 in_gcc_extension = old_gcc_extension;
10013                 break;
10014
10015         DECLARATION_START
10016                 statement = parse_declaration_statement();
10017                 break;
10018
10019         case T___label__:
10020                 statement = parse_local_label_declaration();
10021                 break;
10022
10023         case ';':        statement = parse_empty_statement();         break;
10024         case '{':        statement = parse_compound_statement(false); break;
10025         case T___leave:  statement = parse_leave_statement();         break;
10026         case T___try:    statement = parse_ms_try_statment();         break;
10027         case T_asm:      statement = parse_asm_statement();           break;
10028         case T_break:    statement = parse_break();                   break;
10029         case T_case:     statement = parse_case_statement();          break;
10030         case T_continue: statement = parse_continue();                break;
10031         case T_default:  statement = parse_default_statement();       break;
10032         case T_do:       statement = parse_do();                      break;
10033         case T_for:      statement = parse_for();                     break;
10034         case T_goto:     statement = parse_goto();                    break;
10035         case T_if:       statement = parse_if();                      break;
10036         case T_return:   statement = parse_return();                  break;
10037         case T_switch:   statement = parse_switch();                  break;
10038         case T_while:    statement = parse_while();                   break;
10039
10040         EXPRESSION_START
10041                 statement = parse_expression_statement();
10042                 break;
10043
10044         default:
10045                 errorf(HERE, "unexpected token %K while parsing statement", &token);
10046                 statement = create_invalid_statement();
10047                 if (!at_anchor())
10048                         next_token();
10049                 break;
10050         }
10051         rem_anchor_token(';');
10052
10053         assert(statement != NULL
10054                         && statement->base.source_position.input_name != NULL);
10055
10056         return statement;
10057 }
10058
10059 /**
10060  * parse a statement and emits "statement has no effect" warning if needed
10061  * (This is really a wrapper around intern_parse_statement with check for 1
10062  *  single warning. It is needed, because for statement expressions we have
10063  *  to avoid the warning on the last statement)
10064  */
10065 static statement_t *parse_statement(void)
10066 {
10067         statement_t *statement = intern_parse_statement();
10068
10069         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
10070                 expression_t *expression = statement->expression.expression;
10071                 if (!expression_has_effect(expression)) {
10072                         warningf(&expression->base.source_position,
10073                                         "statement has no effect");
10074                 }
10075         }
10076
10077         return statement;
10078 }
10079
10080 /**
10081  * Parse a compound statement.
10082  */
10083 static statement_t *parse_compound_statement(bool inside_expression_statement)
10084 {
10085         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
10086
10087         PUSH_PARENT(statement);
10088
10089         eat('{');
10090         add_anchor_token('}');
10091
10092         size_t const top       = environment_top();
10093         size_t const top_local = local_label_top();
10094         scope_push(&statement->compound.scope);
10095
10096         statement_t **anchor            = &statement->compound.statements;
10097         bool          only_decls_so_far = true;
10098         while (token.type != '}') {
10099                 if (token.type == T_EOF) {
10100                         errorf(&statement->base.source_position,
10101                                "EOF while parsing compound statement");
10102                         break;
10103                 }
10104                 statement_t *sub_statement = intern_parse_statement();
10105                 if (is_invalid_statement(sub_statement)) {
10106                         /* an error occurred. if we are at an anchor, return */
10107                         if (at_anchor())
10108                                 goto end_error;
10109                         continue;
10110                 }
10111
10112                 if (warning.declaration_after_statement) {
10113                         if (sub_statement->kind != STATEMENT_DECLARATION) {
10114                                 only_decls_so_far = false;
10115                         } else if (!only_decls_so_far) {
10116                                 warningf(&sub_statement->base.source_position,
10117                                          "ISO C90 forbids mixed declarations and code");
10118                         }
10119                 }
10120
10121                 *anchor = sub_statement;
10122
10123                 while (sub_statement->base.next != NULL)
10124                         sub_statement = sub_statement->base.next;
10125
10126                 anchor = &sub_statement->base.next;
10127         }
10128         next_token();
10129
10130         /* look over all statements again to produce no effect warnings */
10131         if (warning.unused_value) {
10132                 statement_t *sub_statement = statement->compound.statements;
10133                 for( ; sub_statement != NULL; sub_statement = sub_statement->base.next) {
10134                         if (sub_statement->kind != STATEMENT_EXPRESSION)
10135                                 continue;
10136                         /* don't emit a warning for the last expression in an expression
10137                          * statement as it has always an effect */
10138                         if (inside_expression_statement && sub_statement->base.next == NULL)
10139                                 continue;
10140
10141                         expression_t *expression = sub_statement->expression.expression;
10142                         if (!expression_has_effect(expression)) {
10143                                 warningf(&expression->base.source_position,
10144                                          "statement has no effect");
10145                         }
10146                 }
10147         }
10148
10149 end_error:
10150         rem_anchor_token('}');
10151         assert(scope == &statement->compound.scope);
10152         scope_pop();
10153         environment_pop_to(top);
10154         local_label_pop_to(top_local);
10155
10156         POP_PARENT;
10157         return statement;
10158 }
10159
10160 /**
10161  * Initialize builtin types.
10162  */
10163 static void initialize_builtin_types(void)
10164 {
10165         type_intmax_t    = make_global_typedef("__intmax_t__",      type_long_long);
10166         type_size_t      = make_global_typedef("__SIZE_TYPE__",     type_unsigned_long);
10167         type_ssize_t     = make_global_typedef("__SSIZE_TYPE__",    type_long);
10168         type_ptrdiff_t   = make_global_typedef("__PTRDIFF_TYPE__",  type_long);
10169         type_uintmax_t   = make_global_typedef("__uintmax_t__",     type_unsigned_long_long);
10170         type_uptrdiff_t  = make_global_typedef("__UPTRDIFF_TYPE__", type_unsigned_long);
10171         type_wchar_t     = make_global_typedef("__WCHAR_TYPE__",    opt_short_wchar_t ? type_unsigned_short : type_int);
10172         type_wint_t      = make_global_typedef("__WINT_TYPE__",     type_int);
10173
10174         type_intmax_t_ptr  = make_pointer_type(type_intmax_t,  TYPE_QUALIFIER_NONE);
10175         type_ptrdiff_t_ptr = make_pointer_type(type_ptrdiff_t, TYPE_QUALIFIER_NONE);
10176         type_ssize_t_ptr   = make_pointer_type(type_ssize_t,   TYPE_QUALIFIER_NONE);
10177         type_wchar_t_ptr   = make_pointer_type(type_wchar_t,   TYPE_QUALIFIER_NONE);
10178
10179         /* const version of wchar_t */
10180         type_const_wchar_t = allocate_type_zero(TYPE_TYPEDEF);
10181         type_const_wchar_t->typedeft.declaration  = type_wchar_t->typedeft.declaration;
10182         type_const_wchar_t->base.qualifiers      |= TYPE_QUALIFIER_CONST;
10183
10184         type_const_wchar_t_ptr = make_pointer_type(type_const_wchar_t, TYPE_QUALIFIER_NONE);
10185 }
10186
10187 /**
10188  * Check for unused global static functions and variables
10189  */
10190 static void check_unused_globals(void)
10191 {
10192         if (!warning.unused_function && !warning.unused_variable)
10193                 return;
10194
10195         for (const declaration_t *decl = file_scope->declarations; decl != NULL; decl = decl->next) {
10196                 if (decl->used                  ||
10197                     decl->modifiers & DM_UNUSED ||
10198                     decl->modifiers & DM_USED   ||
10199                     decl->storage_class != STORAGE_CLASS_STATIC)
10200                         continue;
10201
10202                 type_t *const type = decl->type;
10203                 const char *s;
10204                 if (is_type_function(skip_typeref(type))) {
10205                         if (!warning.unused_function || decl->is_inline)
10206                                 continue;
10207
10208                         s = (decl->init.statement != NULL ? "defined" : "declared");
10209                 } else {
10210                         if (!warning.unused_variable)
10211                                 continue;
10212
10213                         s = "defined";
10214                 }
10215
10216                 warningf(&decl->source_position, "'%#T' %s but not used",
10217                         type, decl->symbol, s);
10218         }
10219 }
10220
10221 static void parse_global_asm(void)
10222 {
10223         statement_t *statement = allocate_statement_zero(STATEMENT_ASM);
10224
10225         eat(T_asm);
10226         expect('(');
10227
10228         statement->asms.asm_text = parse_string_literals();
10229         statement->base.next     = unit->global_asm;
10230         unit->global_asm         = statement;
10231
10232         expect(')');
10233         expect(';');
10234
10235 end_error:;
10236 }
10237
10238 /**
10239  * Parse a translation unit.
10240  */
10241 static void parse_translation_unit(void)
10242 {
10243         add_anchor_token(T_EOF);
10244
10245 #ifndef NDEBUG
10246         unsigned char token_anchor_copy[T_LAST_TOKEN];
10247         memcpy(token_anchor_copy, token_anchor_set, sizeof(token_anchor_copy));
10248 #endif
10249         for (;;) {
10250 #ifndef NDEBUG
10251                 bool anchor_leak = false;
10252                 for (int i = 0; i != T_LAST_TOKEN; ++i) {
10253                         unsigned char count = token_anchor_set[i] - token_anchor_copy[i];
10254                         if (count != 0) {
10255                                 errorf(HERE, "Leaked anchor token %k %d times", i, count);
10256                                 anchor_leak = true;
10257                         }
10258                 }
10259                 if (in_gcc_extension) {
10260                         errorf(HERE, "Leaked __extension__");
10261                         anchor_leak = true;
10262                 }
10263
10264                 if (anchor_leak)
10265                         abort();
10266 #endif
10267
10268                 switch (token.type) {
10269                         DECLARATION_START
10270                         case T_IDENTIFIER:
10271                         case T___extension__:
10272                                 parse_external_declaration();
10273                                 break;
10274
10275                         case T_asm:
10276                                 parse_global_asm();
10277                                 break;
10278
10279                         case T_EOF:
10280                                 rem_anchor_token(T_EOF);
10281                                 return;
10282
10283                         case ';':
10284                                 if (!strict_mode) {
10285                                         if (warning.other)
10286                                                 warningf(HERE, "stray ';' outside of function");
10287                                         next_token();
10288                                         break;
10289                                 }
10290                                 /* FALLTHROUGH */
10291
10292                         default:
10293                                 errorf(HERE, "stray %K outside of function", &token);
10294                                 if (token.type == '(' || token.type == '{' || token.type == '[')
10295                                         eat_until_matching_token(token.type);
10296                                 next_token();
10297                                 break;
10298                 }
10299         }
10300 }
10301
10302 /**
10303  * Parse the input.
10304  *
10305  * @return  the translation unit or NULL if errors occurred.
10306  */
10307 void start_parsing(void)
10308 {
10309         environment_stack = NEW_ARR_F(stack_entry_t, 0);
10310         label_stack       = NEW_ARR_F(stack_entry_t, 0);
10311         local_label_stack = NEW_ARR_F(stack_entry_t, 0);
10312         diagnostic_count  = 0;
10313         error_count       = 0;
10314         warning_count     = 0;
10315
10316         type_set_output(stderr);
10317         ast_set_output(stderr);
10318
10319         assert(unit == NULL);
10320         unit = allocate_ast_zero(sizeof(unit[0]));
10321
10322         assert(file_scope == NULL);
10323         file_scope = &unit->scope;
10324
10325         assert(scope == NULL);
10326         scope_push(&unit->scope);
10327
10328         initialize_builtin_types();
10329 }
10330
10331 translation_unit_t *finish_parsing(void)
10332 {
10333         /* do NOT use scope_pop() here, this will crash, will it by hand */
10334         assert(scope == &unit->scope);
10335         scope            = NULL;
10336         last_declaration = NULL;
10337
10338         assert(file_scope == &unit->scope);
10339         check_unused_globals();
10340         file_scope = NULL;
10341
10342         DEL_ARR_F(environment_stack);
10343         DEL_ARR_F(label_stack);
10344         DEL_ARR_F(local_label_stack);
10345
10346         translation_unit_t *result = unit;
10347         unit = NULL;
10348         return result;
10349 }
10350
10351 void parse(void)
10352 {
10353         lookahead_bufpos = 0;
10354         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
10355                 next_token();
10356         }
10357         parse_translation_unit();
10358 }
10359
10360 /**
10361  * Initialize the parser.
10362  */
10363 void init_parser(void)
10364 {
10365         sym_anonymous = symbol_table_insert("<anonymous>");
10366
10367         if (c_mode & _MS) {
10368                 /* add predefined symbols for extended-decl-modifier */
10369                 sym_align      = symbol_table_insert("align");
10370                 sym_allocate   = symbol_table_insert("allocate");
10371                 sym_dllimport  = symbol_table_insert("dllimport");
10372                 sym_dllexport  = symbol_table_insert("dllexport");
10373                 sym_naked      = symbol_table_insert("naked");
10374                 sym_noinline   = symbol_table_insert("noinline");
10375                 sym_noreturn   = symbol_table_insert("noreturn");
10376                 sym_nothrow    = symbol_table_insert("nothrow");
10377                 sym_novtable   = symbol_table_insert("novtable");
10378                 sym_property   = symbol_table_insert("property");
10379                 sym_get        = symbol_table_insert("get");
10380                 sym_put        = symbol_table_insert("put");
10381                 sym_selectany  = symbol_table_insert("selectany");
10382                 sym_thread     = symbol_table_insert("thread");
10383                 sym_uuid       = symbol_table_insert("uuid");
10384                 sym_deprecated = symbol_table_insert("deprecated");
10385                 sym_restrict   = symbol_table_insert("restrict");
10386                 sym_noalias    = symbol_table_insert("noalias");
10387         }
10388         memset(token_anchor_set, 0, sizeof(token_anchor_set));
10389
10390         init_expression_parsers();
10391         obstack_init(&temp_obst);
10392
10393         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
10394         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
10395 }
10396
10397 /**
10398  * Terminate the parser.
10399  */
10400 void exit_parser(void)
10401 {
10402         obstack_free(&temp_obst, NULL);
10403 }