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 "entity_t.h"
  37 #include "lang_features.h"
  38 #include "walk_statements.h"
  39 #include "warning.h"
  40 #include "adt/bitfiddle.h"
  41 #include "adt/error.h"
  42 #include "adt/array.h"
  43
  44 //#define PRINT_TOKENS
  45 #define MAX_LOOKAHEAD 1
  46
  47 typedef struct {
  48         entity_t           *old_entity;
  49         symbol_t           *symbol;
  50         entity_namespace_t  namespc;
  51 } stack_entry_t;
  52
  53 typedef struct argument_list_t argument_list_t;
  54 struct argument_list_t {
  55         long              argument;
  56         argument_list_t  *next;
  57 };
  58
  59 typedef struct gnu_attribute_t gnu_attribute_t;
  60 struct gnu_attribute_t {
  61         gnu_attribute_kind_t kind;          /**< The kind of the GNU attribute. */
  62         gnu_attribute_t     *next;
  63         bool                 invalid;       /**< Set if this attribute had argument errors, */
  64         bool                 has_arguments; /**< True, if this attribute has arguments. */
  65         union {
  66                 size_t              value;
  67                 string_t            string;
  68                 symbol_t           *symbol;
  69                 long                argument;  /**< Single argument. */
  70                 argument_list_t    *arguments; /**< List of argument expressions. */
  71         } u;
  72 };
  73
  74 typedef struct declaration_specifiers_t  declaration_specifiers_t;
  75 struct declaration_specifiers_t {
  76         source_position_t  source_position;
  77         storage_class_t    storage_class;
  78         unsigned char      alignment;         /**< Alignment, 0 if not set. */
  79         bool               is_inline    : 1;
  80         bool               thread_local : 1;  /**< GCC __thread */
  81         bool               deprecated   : 1;
  82         decl_modifiers_t   modifiers;         /**< declaration modifiers */
  83         gnu_attribute_t   *gnu_attributes;    /**< list of GNU attributes */
  84         const char        *deprecated_string; /**< can be set if declaration was marked deprecated. */
  85         symbol_t          *get_property_sym;  /**< the name of the get property if set. */
  86         symbol_t          *put_property_sym;  /**< the name of the put property if set. */
  87         type_t            *type;
  88 };
  89
  90 /**
  91  * An environment for parsing initializers (and compound literals).
  92  */
  93 typedef struct parse_initializer_env_t {
  94         type_t     *type;   /**< the type of the initializer. In case of an
  95                                  array type with unspecified size this gets
  96                                  adjusted to the actual size. */
  97         entity_t   *entity; /**< the variable that is initialized if any */
  98         bool        must_be_constant;
  99 } parse_initializer_env_t;
 100
 101 typedef entity_t* (*parsed_declaration_func) (entity_t *declaration, bool is_definition);
 102
 103 /** The current token. */
 104 static token_t              token;
 105 /** The lookahead ring-buffer. */
 106 static token_t              lookahead_buffer[MAX_LOOKAHEAD];
 107 /** Position of the next token in the lookahead buffer. */
 108 static size_t               lookahead_bufpos;
 109 static stack_entry_t       *environment_stack = NULL;
 110 static stack_entry_t       *label_stack       = NULL;
 111 static scope_t             *file_scope        = NULL;
 112 static scope_t             *current_scope     = NULL;
 113 /** Point to the current function declaration if inside a function. */
 114 static function_t          *current_function  = NULL;
 115 static entity_t            *current_init_decl = NULL;
 116 static switch_statement_t  *current_switch    = NULL;
 117 static statement_t         *current_loop      = NULL;
 118 static statement_t         *current_parent    = NULL;
 119 static ms_try_statement_t  *current_try       = NULL;
 120 static linkage_kind_t       current_linkage   = LINKAGE_INVALID;
 121 static goto_statement_t    *goto_first        = NULL;
 122 static goto_statement_t   **goto_anchor       = NULL;
 123 static label_statement_t   *label_first       = NULL;
 124 static label_statement_t  **label_anchor      = NULL;
 125 /** current translation unit. */
 126 static translation_unit_t  *unit              = NULL;
 127 /** true if we are in a type property context (evaluation only for type. */
 128 static bool                 in_type_prop      = false;
 129 /** true in we are in a __extension__ context. */
 130 static bool                 in_gcc_extension  = false;
 131 static struct obstack       temp_obst;
 132 static entity_t            *anonymous_entity;
 133 static declaration_t      **incomplete_arrays;
 134
 135
 136 #define PUSH_PARENT(stmt)                          \
 137         statement_t *const prev_parent = current_parent; \
 138         ((void)(current_parent = (stmt)))
 139 #define POP_PARENT ((void)(current_parent = prev_parent))
 140
 141 /** special symbol used for anonymous entities. */
 142 static const symbol_t *sym_anonymous = NULL;
 143
 144 /* symbols for Microsoft extended-decl-modifier */
 145 static const symbol_t *sym_align         = NULL;
 146 static const symbol_t *sym_allocate      = NULL;
 147 static const symbol_t *sym_dllimport     = NULL;
 148 static const symbol_t *sym_dllexport     = NULL;
 149 static const symbol_t *sym_naked         = NULL;
 150 static const symbol_t *sym_noinline      = NULL;
 151 static const symbol_t *sym_returns_twice = NULL;
 152 static const symbol_t *sym_noreturn      = NULL;
 153 static const symbol_t *sym_nothrow       = NULL;
 154 static const symbol_t *sym_novtable      = NULL;
 155 static const symbol_t *sym_property      = NULL;
 156 static const symbol_t *sym_get           = NULL;
 157 static const symbol_t *sym_put           = NULL;
 158 static const symbol_t *sym_selectany     = NULL;
 159 static const symbol_t *sym_thread        = NULL;
 160 static const symbol_t *sym_uuid          = NULL;
 161 static const symbol_t *sym_deprecated    = NULL;
 162 static const symbol_t *sym_restrict      = NULL;
 163 static const symbol_t *sym_noalias       = NULL;
 164
 165 /** The token anchor set */
 166 static unsigned char token_anchor_set[T_LAST_TOKEN];
 167
 168 /** The current source position. */
 169 #define HERE (&token.source_position)
 170
 171 /** true if we are in GCC mode. */
 172 #define GNU_MODE ((c_mode & _GNUC) || in_gcc_extension)
 173
 174 static statement_t *parse_compound_statement(bool inside_expression_statement);
 175 static statement_t *parse_statement(void);
 176
 177 static expression_t *parse_sub_expression(precedence_t);
 178 static expression_t *parse_expression(void);
 179 static type_t       *parse_typename(void);
 180 static void          parse_externals(void);
 181 static void          parse_external(void);
 182
 183 static void parse_compound_type_entries(compound_t *compound_declaration);
 184
 185 static void check_call_argument(type_t          *expected_type,
 186                                                                 call_argument_t *argument, unsigned pos);
 187
 188 typedef enum declarator_flags_t {
 189         DECL_FLAGS_NONE             = 0,
 190         DECL_MAY_BE_ABSTRACT        = 1U << 0,
 191         DECL_CREATE_COMPOUND_MEMBER = 1U << 1,
 192         DECL_IS_PARAMETER           = 1U << 2
 193 } declarator_flags_t;
 194
 195 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
 196                                   declarator_flags_t flags);
 197
 198 static entity_t *record_entity(entity_t *entity, bool is_definition);
 199
 200 static void semantic_comparison(binary_expression_t *expression);
 201
 202 static void create_gnu_builtins(void);
 203 static void create_microsoft_intrinsics(void);
 204
 205 #define STORAGE_CLASSES       \
 206         STORAGE_CLASSES_NO_EXTERN \
 207         case T_extern:
 208
 209 #define STORAGE_CLASSES_NO_EXTERN \
 210         case T_typedef:         \
 211         case T_static:          \
 212         case T_auto:            \
 213         case T_register:        \
 214         case T___thread:
 215
 216 #define TYPE_QUALIFIERS     \
 217         case T_const:           \
 218         case T_restrict:        \
 219         case T_volatile:        \
 220         case T_inline:          \
 221         case T__forceinline:    \
 222         case T___attribute__:
 223
 224 #define COMPLEX_SPECIFIERS  \
 225         case T__Complex:
 226 #define IMAGINARY_SPECIFIERS \
 227         case T__Imaginary:
 228
 229 #define TYPE_SPECIFIERS       \
 230         case T__Bool:             \
 231         case T___builtin_va_list: \
 232         case T___typeof__:        \
 233         case T__declspec:         \
 234         case T_bool:              \
 235         case T_char:              \
 236         case T_double:            \
 237         case T_enum:              \
 238         case T_float:             \
 239         case T_int:               \
 240         case T_long:              \
 241         case T_short:             \
 242         case T_signed:            \
 243         case T_struct:            \
 244         case T_union:             \
 245         case T_unsigned:          \
 246         case T_void:              \
 247         case T_wchar_t:           \
 248         COMPLEX_SPECIFIERS        \
 249         IMAGINARY_SPECIFIERS
 250
 251 #define DECLARATION_START   \
 252         STORAGE_CLASSES         \
 253         TYPE_QUALIFIERS         \
 254         TYPE_SPECIFIERS
 255
 256 #define DECLARATION_START_NO_EXTERN \
 257         STORAGE_CLASSES_NO_EXTERN       \
 258         TYPE_QUALIFIERS                 \
 259         TYPE_SPECIFIERS
 260
 261 #define TYPENAME_START      \
 262         TYPE_QUALIFIERS         \
 263         TYPE_SPECIFIERS
 264
 265 #define EXPRESSION_START           \
 266         case '!':                        \
 267         case '&':                        \
 268         case '(':                        \
 269         case '*':                        \
 270         case '+':                        \
 271         case '-':                        \
 272         case '~':                        \
 273         case T_ANDAND:                   \
 274         case T_CHARACTER_CONSTANT:       \
 275         case T_FLOATINGPOINT:            \
 276         case T_INTEGER:                  \
 277         case T_MINUSMINUS:               \
 278         case T_PLUSPLUS:                 \
 279         case T_STRING_LITERAL:           \
 280         case T_WIDE_CHARACTER_CONSTANT:  \
 281         case T_WIDE_STRING_LITERAL:      \
 282         case T___FUNCDNAME__:            \
 283         case T___FUNCSIG__:              \
 284         case T___FUNCTION__:             \
 285         case T___PRETTY_FUNCTION__:      \
 286         case T___alignof__:              \
 287         case T___builtin_classify_type:  \
 288         case T___builtin_constant_p:     \
 289         case T___builtin_isgreater:      \
 290         case T___builtin_isgreaterequal: \
 291         case T___builtin_isless:         \
 292         case T___builtin_islessequal:    \
 293         case T___builtin_islessgreater:  \
 294         case T___builtin_isunordered:    \
 295         case T___builtin_offsetof:       \
 296         case T___builtin_va_arg:         \
 297         case T___builtin_va_start:       \
 298         case T___builtin_va_copy:        \
 299         case T___func__:                 \
 300         case T___noop:                   \
 301         case T__assume:                  \
 302         case T_delete:                   \
 303         case T_false:                    \
 304         case T_sizeof:                   \
 305         case T_throw:                    \
 306         case T_true:
 307
 308 /**
 309  * Allocate an AST node with given size and
 310  * initialize all fields with zero.
 311  */
 312 static void *allocate_ast_zero(size_t size)
 313 {
 314         void *res = allocate_ast(size);
 315         memset(res, 0, size);
 316         return res;
 317 }
 318
 319 /**
 320  * Returns the size of an entity node.
 321  *
 322  * @param kind  the entity kind
 323  */
 324 static size_t get_entity_struct_size(entity_kind_t kind)
 325 {
 326         static const size_t sizes[] = {
 327                 [ENTITY_VARIABLE]        = sizeof(variable_t),
 328                 [ENTITY_PARAMETER]       = sizeof(parameter_t),
 329                 [ENTITY_COMPOUND_MEMBER] = sizeof(compound_member_t),
 330                 [ENTITY_FUNCTION]        = sizeof(function_t),
 331                 [ENTITY_TYPEDEF]         = sizeof(typedef_t),
 332                 [ENTITY_STRUCT]          = sizeof(compound_t),
 333                 [ENTITY_UNION]           = sizeof(compound_t),
 334                 [ENTITY_ENUM]            = sizeof(enum_t),
 335                 [ENTITY_ENUM_VALUE]      = sizeof(enum_value_t),
 336                 [ENTITY_LABEL]           = sizeof(label_t),
 337                 [ENTITY_LOCAL_LABEL]     = sizeof(label_t),
 338                 [ENTITY_NAMESPACE]       = sizeof(namespace_t)
 339         };
 340         assert(kind < lengthof(sizes));
 341         assert(sizes[kind] != 0);
 342         return sizes[kind];
 343 }
 344
 345 /**
 346  * Allocate an entity of given kind and initialize all
 347  * fields with zero.
 348  *
 349  * @param kind   the kind of the entity to allocate
 350  */
 351 static entity_t *allocate_entity_zero(entity_kind_t kind)
 352 {
 353         size_t    size   = get_entity_struct_size(kind);
 354         entity_t *entity = allocate_ast_zero(size);
 355         entity->kind     = kind;
 356         return entity;
 357 }
 358
 359 /**
 360  * Returns the size of a statement node.
 361  *
 362  * @param kind  the statement kind
 363  */
 364 static size_t get_statement_struct_size(statement_kind_t kind)
 365 {
 366         static const size_t sizes[] = {
 367                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 368                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 369                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 370                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 371                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 372                 [STATEMENT_IF]          = sizeof(if_statement_t),
 373                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 374                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 375                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 376                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 377                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 378                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 379                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 380                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 381                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 382                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 383                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 384                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 385                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 386         };
 387         assert(kind < lengthof(sizes));
 388         assert(sizes[kind] != 0);
 389         return sizes[kind];
 390 }
 391
 392 /**
 393  * Returns the size of an expression node.
 394  *
 395  * @param kind  the expression kind
 396  */
 397 static size_t get_expression_struct_size(expression_kind_t kind)
 398 {
 399         static const size_t sizes[] = {
 400                 [EXPR_INVALID]                    = sizeof(expression_base_t),
 401                 [EXPR_REFERENCE]                  = sizeof(reference_expression_t),
 402                 [EXPR_REFERENCE_ENUM_VALUE]       = sizeof(reference_expression_t),
 403                 [EXPR_CONST]                      = sizeof(const_expression_t),
 404                 [EXPR_CHARACTER_CONSTANT]         = sizeof(const_expression_t),
 405                 [EXPR_WIDE_CHARACTER_CONSTANT]    = sizeof(const_expression_t),
 406                 [EXPR_STRING_LITERAL]             = sizeof(string_literal_expression_t),
 407                 [EXPR_WIDE_STRING_LITERAL]        = sizeof(wide_string_literal_expression_t),
 408                 [EXPR_COMPOUND_LITERAL]           = sizeof(compound_literal_expression_t),
 409                 [EXPR_CALL]                       = sizeof(call_expression_t),
 410                 [EXPR_UNARY_FIRST]                = sizeof(unary_expression_t),
 411                 [EXPR_BINARY_FIRST]               = sizeof(binary_expression_t),
 412                 [EXPR_CONDITIONAL]                = sizeof(conditional_expression_t),
 413                 [EXPR_SELECT]                     = sizeof(select_expression_t),
 414                 [EXPR_ARRAY_ACCESS]               = sizeof(array_access_expression_t),
 415                 [EXPR_SIZEOF]                     = sizeof(typeprop_expression_t),
 416                 [EXPR_ALIGNOF]                    = sizeof(typeprop_expression_t),
 417                 [EXPR_CLASSIFY_TYPE]              = sizeof(classify_type_expression_t),
 418                 [EXPR_FUNCNAME]                   = sizeof(funcname_expression_t),
 419                 [EXPR_BUILTIN_CONSTANT_P]         = sizeof(builtin_constant_expression_t),
 420                 [EXPR_BUILTIN_TYPES_COMPATIBLE_P] = sizeof(builtin_types_compatible_expression_t),
 421                 [EXPR_OFFSETOF]                   = sizeof(offsetof_expression_t),
 422                 [EXPR_VA_START]                   = sizeof(va_start_expression_t),
 423                 [EXPR_VA_ARG]                     = sizeof(va_arg_expression_t),
 424                 [EXPR_VA_COPY]                    = sizeof(va_copy_expression_t),
 425                 [EXPR_STATEMENT]                  = sizeof(statement_expression_t),
 426                 [EXPR_LABEL_ADDRESS]              = sizeof(label_address_expression_t),
 427         };
 428         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 429                 return sizes[EXPR_UNARY_FIRST];
 430         }
 431         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 432                 return sizes[EXPR_BINARY_FIRST];
 433         }
 434         assert(kind < lengthof(sizes));
 435         assert(sizes[kind] != 0);
 436         return sizes[kind];
 437 }
 438
 439 /**
 440  * Allocate a statement node of given kind and initialize all
 441  * fields with zero. Sets its source position to the position
 442  * of the current token.
 443  */
 444 static statement_t *allocate_statement_zero(statement_kind_t kind)
 445 {
 446         size_t       size = get_statement_struct_size(kind);
 447         statement_t *res  = allocate_ast_zero(size);
 448
 449         res->base.kind            = kind;
 450         res->base.parent          = current_parent;
 451         res->base.source_position = token.source_position;
 452         return res;
 453 }
 454
 455 /**
 456  * Allocate an expression node of given kind and initialize all
 457  * fields with zero.
 458  *
 459  * @param kind  the kind of the expression to allocate
 460  */
 461 static expression_t *allocate_expression_zero(expression_kind_t kind)
 462 {
 463         size_t        size = get_expression_struct_size(kind);
 464         expression_t *res  = allocate_ast_zero(size);
 465
 466         res->base.kind            = kind;
 467         res->base.type            = type_error_type;
 468         res->base.source_position = token.source_position;
 469         return res;
 470 }
 471
 472 /**
 473  * Creates a new invalid expression at the source position
 474  * of the current token.
 475  */
 476 static expression_t *create_invalid_expression(void)
 477 {
 478         return allocate_expression_zero(EXPR_INVALID);
 479 }
 480
 481 /**
 482  * Creates a new invalid statement.
 483  */
 484 static statement_t *create_invalid_statement(void)
 485 {
 486         return allocate_statement_zero(STATEMENT_INVALID);
 487 }
 488
 489 /**
 490  * Allocate a new empty statement.
 491  */
 492 static statement_t *create_empty_statement(void)
 493 {
 494         return allocate_statement_zero(STATEMENT_EMPTY);
 495 }
 496
 497 /**
 498  * Returns the size of a type node.
 499  *
 500  * @param kind  the type kind
 501  */
 502 static size_t get_type_struct_size(type_kind_t kind)
 503 {
 504         static const size_t sizes[] = {
 505                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
 506                 [TYPE_COMPLEX]         = sizeof(complex_type_t),
 507                 [TYPE_IMAGINARY]       = sizeof(imaginary_type_t),
 508                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
 509                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
 510                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
 511                 [TYPE_ENUM]            = sizeof(enum_type_t),
 512                 [TYPE_FUNCTION]        = sizeof(function_type_t),
 513                 [TYPE_POINTER]         = sizeof(pointer_type_t),
 514                 [TYPE_ARRAY]           = sizeof(array_type_t),
 515                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
 516                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
 517                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
 518         };
 519         assert(lengthof(sizes) == (int)TYPE_TYPEOF + 1);
 520         assert(kind <= TYPE_TYPEOF);
 521         assert(sizes[kind] != 0);
 522         return sizes[kind];
 523 }
 524
 525 /**
 526  * Allocate a type node of given kind and initialize all
 527  * fields with zero.
 528  *
 529  * @param kind             type kind to allocate
 530  */
 531 static type_t *allocate_type_zero(type_kind_t kind)
 532 {
 533         size_t  size = get_type_struct_size(kind);
 534         type_t *res  = obstack_alloc(type_obst, size);
 535         memset(res, 0, size);
 536         res->base.kind = kind;
 537
 538         return res;
 539 }
 540
 541 static function_parameter_t *allocate_parameter(type_t *const type)
 542 {
 543         function_parameter_t *const param = obstack_alloc(type_obst, sizeof(*param));
 544         memset(param, 0, sizeof(*param));
 545         param->type = type;
 546         return param;
 547 }
 548
 549 /**
 550  * Returns the size of an initializer node.
 551  *
 552  * @param kind  the initializer kind
 553  */
 554 static size_t get_initializer_size(initializer_kind_t kind)
 555 {
 556         static const size_t sizes[] = {
 557                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 558                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 559                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 560                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 561                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 562         };
 563         assert(kind < lengthof(sizes));
 564         assert(sizes[kind] != 0);
 565         return sizes[kind];
 566 }
 567
 568 /**
 569  * Allocate an initializer node of given kind and initialize all
 570  * fields with zero.
 571  */
 572 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 573 {
 574         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 575         result->kind          = kind;
 576
 577         return result;
 578 }
 579
 580 /**
 581  * Returns the index of the top element of the environment stack.
 582  */
 583 static size_t environment_top(void)
 584 {
 585         return ARR_LEN(environment_stack);
 586 }
 587
 588 /**
 589  * Returns the index of the top element of the global label stack.
 590  */
 591 static size_t label_top(void)
 592 {
 593         return ARR_LEN(label_stack);
 594 }
 595
 596 /**
 597  * Return the next token.
 598  */
 599 static inline void next_token(void)
 600 {
 601         token                              = lookahead_buffer[lookahead_bufpos];
 602         lookahead_buffer[lookahead_bufpos] = lexer_token;
 603         lexer_next_token();
 604
 605         lookahead_bufpos = (lookahead_bufpos + 1) % MAX_LOOKAHEAD;
 606
 607 #ifdef PRINT_TOKENS
 608         print_token(stderr, &token);
 609         fprintf(stderr, "\n");
 610 #endif
 611 }
 612
 613 /**
 614  * Return the next token with a given lookahead.
 615  */
 616 static inline const token_t *look_ahead(size_t num)
 617 {
 618         assert(0 < num && num <= MAX_LOOKAHEAD);
 619         size_t pos = (lookahead_bufpos + num - 1) % MAX_LOOKAHEAD;
 620         return &lookahead_buffer[pos];
 621 }
 622
 623 /**
 624  * Adds a token type to the token type anchor set (a multi-set).
 625  */
 626 static void add_anchor_token(int token_type)
 627 {
 628         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 629         ++token_anchor_set[token_type];
 630 }
 631
 632 /**
 633  * Set the number of tokens types of the given type
 634  * to zero and return the old count.
 635  */
 636 static int save_and_reset_anchor_state(int token_type)
 637 {
 638         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 639         int count = token_anchor_set[token_type];
 640         token_anchor_set[token_type] = 0;
 641         return count;
 642 }
 643
 644 /**
 645  * Restore the number of token types to the given count.
 646  */
 647 static void restore_anchor_state(int token_type, int count)
 648 {
 649         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 650         token_anchor_set[token_type] = count;
 651 }
 652
 653 /**
 654  * Remove a token type from the token type anchor set (a multi-set).
 655  */
 656 static void rem_anchor_token(int token_type)
 657 {
 658         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 659         assert(token_anchor_set[token_type] != 0);
 660         --token_anchor_set[token_type];
 661 }
 662
 663 /**
 664  * Return true if the token type of the current token is
 665  * in the anchor set.
 666  */
 667 static bool at_anchor(void)
 668 {
 669         if (token.type < 0)
 670                 return false;
 671         return token_anchor_set[token.type];
 672 }
 673
 674 /**
 675  * Eat tokens until a matching token type is found.
 676  */
 677 static void eat_until_matching_token(int type)
 678 {
 679         int end_token;
 680         switch (type) {
 681                 case '(': end_token = ')';  break;
 682                 case '{': end_token = '}';  break;
 683                 case '[': end_token = ']';  break;
 684                 default:  end_token = type; break;
 685         }
 686
 687         unsigned parenthesis_count = 0;
 688         unsigned brace_count       = 0;
 689         unsigned bracket_count     = 0;
 690         while (token.type        != end_token ||
 691                parenthesis_count != 0         ||
 692                brace_count       != 0         ||
 693                bracket_count     != 0) {
 694                 switch (token.type) {
 695                 case T_EOF: return;
 696                 case '(': ++parenthesis_count; break;
 697                 case '{': ++brace_count;       break;
 698                 case '[': ++bracket_count;     break;
 699
 700                 case ')':
 701                         if (parenthesis_count > 0)
 702                                 --parenthesis_count;
 703                         goto check_stop;
 704
 705                 case '}':
 706                         if (brace_count > 0)
 707                                 --brace_count;
 708                         goto check_stop;
 709
 710                 case ']':
 711                         if (bracket_count > 0)
 712                                 --bracket_count;
 713 check_stop:
 714                         if (token.type        == end_token &&
 715                             parenthesis_count == 0         &&
 716                             brace_count       == 0         &&
 717                             bracket_count     == 0)
 718                                 return;
 719                         break;
 720
 721                 default:
 722                         break;
 723                 }
 724                 next_token();
 725         }
 726 }
 727
 728 /**
 729  * Eat input tokens until an anchor is found.
 730  */
 731 static void eat_until_anchor(void)
 732 {
 733         while (token_anchor_set[token.type] == 0) {
 734                 if (token.type == '(' || token.type == '{' || token.type == '[')
 735                         eat_until_matching_token(token.type);
 736                 next_token();
 737         }
 738 }
 739
 740 /**
 741  * Eat a whole block from input tokens.
 742  */
 743 static void eat_block(void)
 744 {
 745         eat_until_matching_token('{');
 746         if (token.type == '}')
 747                 next_token();
 748 }
 749
 750 #define eat(token_type) (assert(token.type == (token_type)), next_token())
 751
 752 /**
 753  * Report a parse error because an expected token was not found.
 754  */
 755 static
 756 #if defined __GNUC__ && __GNUC__ >= 4
 757 __attribute__((sentinel))
 758 #endif
 759 void parse_error_expected(const char *message, ...)
 760 {
 761         if (message != NULL) {
 762                 errorf(HERE, "%s", message);
 763         }
 764         va_list ap;
 765         va_start(ap, message);
 766         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 767         va_end(ap);
 768 }
 769
 770 /**
 771  * Report an incompatible type.
 772  */
 773 static void type_error_incompatible(const char *msg,
 774                 const source_position_t *source_position, type_t *type1, type_t *type2)
 775 {
 776         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 777                msg, type1, type2);
 778 }
 779
 780 /**
 781  * Expect the current token is the expected token.
 782  * If not, generate an error, eat the current statement,
 783  * and goto the end_error label.
 784  */
 785 #define expect(expected, error_label)                     \
 786         do {                                                  \
 787                 if (UNLIKELY(token.type != (expected))) {         \
 788                         parse_error_expected(NULL, (expected), NULL); \
 789                         add_anchor_token(expected);                   \
 790                         eat_until_anchor();                           \
 791                         if (token.type == expected)                   \
 792                                 next_token();                             \
 793                         rem_anchor_token(expected);                   \
 794                         goto error_label;                             \
 795                 }                                                 \
 796                 next_token();                                     \
 797         } while (0)
 798
 799 /**
 800  * Push a given scope on the scope stack and make it the
 801  * current scope
 802  */
 803 static scope_t *scope_push(scope_t *new_scope)
 804 {
 805         if (current_scope != NULL) {
 806                 new_scope->depth = current_scope->depth + 1;
 807         }
 808
 809         scope_t *old_scope = current_scope;
 810         current_scope      = new_scope;
 811         return old_scope;
 812 }
 813
 814 /**
 815  * Pop the current scope from the scope stack.
 816  */
 817 static void scope_pop(scope_t *old_scope)
 818 {
 819         current_scope = old_scope;
 820 }
 821
 822 /**
 823  * Search an entity by its symbol in a given namespace.
 824  */
 825 static entity_t *get_entity(const symbol_t *const symbol,
 826                             namespace_tag_t namespc)
 827 {
 828         entity_t *entity = symbol->entity;
 829         for (; entity != NULL; entity = entity->base.symbol_next) {
 830                 if (entity->base.namespc == namespc)
 831                         return entity;
 832         }
 833
 834         return NULL;
 835 }
 836
 837 /* §6.2.3:1 24)  There is only one name space for tags even though three are
 838  * possible. */
 839 static entity_t *get_tag(symbol_t const *const symbol,
 840                 entity_kind_tag_t const kind)
 841 {
 842         entity_t *entity = get_entity(symbol, NAMESPACE_TAG);
 843         if (entity != NULL && entity->kind != kind) {
 844                 errorf(HERE,
 845                                 "'%Y' defined as wrong kind of tag (previous definition %P)",
 846                                 symbol, &entity->base.source_position);
 847                 entity = NULL;
 848         }
 849         return entity;
 850 }
 851
 852 /**
 853  * pushs an entity on the environment stack and links the corresponding symbol
 854  * it.
 855  */
 856 static void stack_push(stack_entry_t **stack_ptr, entity_t *entity)
 857 {
 858         symbol_t           *symbol  = entity->base.symbol;
 859         entity_namespace_t  namespc = entity->base.namespc;
 860         assert(namespc != NAMESPACE_INVALID);
 861
 862         /* replace/add entity into entity list of the symbol */
 863         entity_t **anchor;
 864         entity_t  *iter;
 865         for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 866                 iter = *anchor;
 867                 if (iter == NULL)
 868                         break;
 869
 870                 /* replace an entry? */
 871                 if (iter->base.namespc == namespc) {
 872                         entity->base.symbol_next = iter->base.symbol_next;
 873                         break;
 874                 }
 875         }
 876         *anchor = entity;
 877
 878         /* remember old declaration */
 879         stack_entry_t entry;
 880         entry.symbol     = symbol;
 881         entry.old_entity = iter;
 882         entry.namespc    = namespc;
 883         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 884 }
 885
 886 /**
 887  * Push an entity on the environment stack.
 888  */
 889 static void environment_push(entity_t *entity)
 890 {
 891         assert(entity->base.source_position.input_name != NULL);
 892         assert(entity->base.parent_scope != NULL);
 893         stack_push(&environment_stack, entity);
 894 }
 895
 896 /**
 897  * Push a declaration on the global label stack.
 898  *
 899  * @param declaration  the declaration
 900  */
 901 static void label_push(entity_t *label)
 902 {
 903         /* we abuse the parameters scope as parent for the labels */
 904         label->base.parent_scope = &current_function->parameters;
 905         stack_push(&label_stack, label);
 906 }
 907
 908 /**
 909  * pops symbols from the environment stack until @p new_top is the top element
 910  */
 911 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 912 {
 913         stack_entry_t *stack = *stack_ptr;
 914         size_t         top   = ARR_LEN(stack);
 915         size_t         i;
 916
 917         assert(new_top <= top);
 918         if (new_top == top)
 919                 return;
 920
 921         for (i = top; i > new_top; --i) {
 922                 stack_entry_t *entry = &stack[i - 1];
 923
 924                 entity_t           *old_entity = entry->old_entity;
 925                 symbol_t           *symbol     = entry->symbol;
 926                 entity_namespace_t  namespc    = entry->namespc;
 927
 928                 /* replace with old_entity/remove */
 929                 entity_t **anchor;
 930                 entity_t  *iter;
 931                 for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 932                         iter = *anchor;
 933                         assert(iter != NULL);
 934                         /* replace an entry? */
 935                         if (iter->base.namespc == namespc)
 936                                 break;
 937                 }
 938
 939                 /* restore definition from outer scopes (if there was one) */
 940                 if (old_entity != NULL) {
 941                         old_entity->base.symbol_next = iter->base.symbol_next;
 942                         *anchor                      = old_entity;
 943                 } else {
 944                         /* remove entry from list */
 945                         *anchor = iter->base.symbol_next;
 946                 }
 947         }
 948
 949         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
 950 }
 951
 952 /**
 953  * Pop all entries from the environment stack until the new_top
 954  * is reached.
 955  *
 956  * @param new_top  the new stack top
 957  */
 958 static void environment_pop_to(size_t new_top)
 959 {
 960         stack_pop_to(&environment_stack, new_top);
 961 }
 962
 963 /**
 964  * Pop all entries from the global label stack until the new_top
 965  * is reached.
 966  *
 967  * @param new_top  the new stack top
 968  */
 969 static void label_pop_to(size_t new_top)
 970 {
 971         stack_pop_to(&label_stack, new_top);
 972 }
 973
 974 static int get_akind_rank(atomic_type_kind_t akind)
 975 {
 976         return (int) akind;
 977 }
 978
 979 /**
 980  * Return the type rank for an atomic type.
 981  */
 982 static int get_rank(const type_t *type)
 983 {
 984         assert(!is_typeref(type));
 985         if (type->kind == TYPE_ENUM)
 986                 return get_akind_rank(type->enumt.akind);
 987
 988         assert(type->kind == TYPE_ATOMIC);
 989         return get_akind_rank(type->atomic.akind);
 990 }
 991
 992 /**
 993  * Do integer promotion for a given type.
 994  *
 995  * @param type  the type to promote
 996  * @return the promoted type
 997  */
 998 static type_t *promote_integer(type_t *type)
 999 {
1000         if (type->kind == TYPE_BITFIELD)
1001                 type = type->bitfield.base_type;
1002
1003         if (get_rank(type) < get_akind_rank(ATOMIC_TYPE_INT))
1004                 type = type_int;
1005
1006         return type;
1007 }
1008
1009 /**
1010  * Create a cast expression.
1011  *
1012  * @param expression  the expression to cast
1013  * @param dest_type   the destination type
1014  */
1015 static expression_t *create_cast_expression(expression_t *expression,
1016                                             type_t *dest_type)
1017 {
1018         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
1019
1020         cast->unary.value = expression;
1021         cast->base.type   = dest_type;
1022
1023         return cast;
1024 }
1025
1026 /**
1027  * Check if a given expression represents a null pointer constant.
1028  *
1029  * @param expression  the expression to check
1030  */
1031 static bool is_null_pointer_constant(const expression_t *expression)
1032 {
1033         /* skip void* cast */
1034         if (expression->kind == EXPR_UNARY_CAST ||
1035                         expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
1036                 type_t *const type = skip_typeref(expression->base.type);
1037                 if (types_compatible(type, type_void_ptr))
1038                         expression = expression->unary.value;
1039         }
1040
1041         type_t *const type = skip_typeref(expression->base.type);
1042         return
1043                 is_type_integer(type)              &&
1044                 is_constant_expression(expression) &&
1045                 fold_constant(expression) == 0;
1046 }
1047
1048 /**
1049  * Create an implicit cast expression.
1050  *
1051  * @param expression  the expression to cast
1052  * @param dest_type   the destination type
1053  */
1054 static expression_t *create_implicit_cast(expression_t *expression,
1055                                           type_t *dest_type)
1056 {
1057         type_t *const source_type = expression->base.type;
1058
1059         if (source_type == dest_type)
1060                 return expression;
1061
1062         return create_cast_expression(expression, dest_type);
1063 }
1064
1065 typedef enum assign_error_t {
1066         ASSIGN_SUCCESS,
1067         ASSIGN_ERROR_INCOMPATIBLE,
1068         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
1069         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
1070         ASSIGN_WARNING_POINTER_FROM_INT,
1071         ASSIGN_WARNING_INT_FROM_POINTER
1072 } assign_error_t;
1073
1074 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
1075                                 const expression_t *const right,
1076                                 const char *context,
1077                                 const source_position_t *source_position)
1078 {
1079         type_t *const orig_type_right = right->base.type;
1080         type_t *const type_left       = skip_typeref(orig_type_left);
1081         type_t *const type_right      = skip_typeref(orig_type_right);
1082
1083         switch (error) {
1084         case ASSIGN_SUCCESS:
1085                 return;
1086         case ASSIGN_ERROR_INCOMPATIBLE:
1087                 errorf(source_position,
1088                        "destination type '%T' in %s is incompatible with type '%T'",
1089                        orig_type_left, context, orig_type_right);
1090                 return;
1091
1092         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
1093                 if (warning.other) {
1094                         type_t *points_to_left  = skip_typeref(type_left->pointer.points_to);
1095                         type_t *points_to_right = skip_typeref(type_right->pointer.points_to);
1096
1097                         /* the left type has all qualifiers from the right type */
1098                         unsigned missing_qualifiers
1099                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1100                         warningf(source_position,
1101                                         "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
1102                                         orig_type_left, context, orig_type_right, missing_qualifiers);
1103                 }
1104                 return;
1105         }
1106
1107         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
1108                 if (warning.other) {
1109                         warningf(source_position,
1110                                         "destination type '%T' in %s is incompatible with '%E' of type '%T'",
1111                                         orig_type_left, context, right, orig_type_right);
1112                 }
1113                 return;
1114
1115         case ASSIGN_WARNING_POINTER_FROM_INT:
1116                 if (warning.other) {
1117                         warningf(source_position,
1118                                         "%s makes pointer '%T' from integer '%T' without a cast",
1119                                         context, orig_type_left, orig_type_right);
1120                 }
1121                 return;
1122
1123         case ASSIGN_WARNING_INT_FROM_POINTER:
1124                 if (warning.other) {
1125                         warningf(source_position,
1126                                         "%s makes integer '%T' from pointer '%T' without a cast",
1127                                         context, orig_type_left, orig_type_right);
1128                 }
1129                 return;
1130
1131         default:
1132                 panic("invalid error value");
1133         }
1134 }
1135
1136 /** Implements the rules from §6.5.16.1 */
1137 static assign_error_t semantic_assign(type_t *orig_type_left,
1138                                       const expression_t *const right)
1139 {
1140         type_t *const orig_type_right = right->base.type;
1141         type_t *const type_left       = skip_typeref(orig_type_left);
1142         type_t *const type_right      = skip_typeref(orig_type_right);
1143
1144         if (is_type_pointer(type_left)) {
1145                 if (is_null_pointer_constant(right)) {
1146                         return ASSIGN_SUCCESS;
1147                 } else if (is_type_pointer(type_right)) {
1148                         type_t *points_to_left
1149                                 = skip_typeref(type_left->pointer.points_to);
1150                         type_t *points_to_right
1151                                 = skip_typeref(type_right->pointer.points_to);
1152                         assign_error_t res = ASSIGN_SUCCESS;
1153
1154                         /* the left type has all qualifiers from the right type */
1155                         unsigned missing_qualifiers
1156                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1157                         if (missing_qualifiers != 0) {
1158                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1159                         }
1160
1161                         points_to_left  = get_unqualified_type(points_to_left);
1162                         points_to_right = get_unqualified_type(points_to_right);
1163
1164                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID))
1165                                 return res;
1166
1167                         if (is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1168                                 /* ISO/IEC 14882:1998(E) §C.1.2:6 */
1169                                 return c_mode & _CXX ? ASSIGN_ERROR_INCOMPATIBLE : res;
1170                         }
1171
1172                         if (!types_compatible(points_to_left, points_to_right)) {
1173                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1174                         }
1175
1176                         return res;
1177                 } else if (is_type_integer(type_right)) {
1178                         return ASSIGN_WARNING_POINTER_FROM_INT;
1179                 }
1180         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1181             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1182                 && is_type_pointer(type_right))) {
1183                 return ASSIGN_SUCCESS;
1184         } else if ((is_type_compound(type_left)  && is_type_compound(type_right))
1185                         || (is_type_builtin(type_left) && is_type_builtin(type_right))) {
1186                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1187                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1188                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1189                         return ASSIGN_SUCCESS;
1190                 }
1191         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1192                 return ASSIGN_WARNING_INT_FROM_POINTER;
1193         }
1194
1195         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1196                 return ASSIGN_SUCCESS;
1197
1198         return ASSIGN_ERROR_INCOMPATIBLE;
1199 }
1200
1201 static expression_t *parse_constant_expression(void)
1202 {
1203         expression_t *result = parse_sub_expression(PREC_CONDITIONAL);
1204
1205         if (!is_constant_expression(result)) {
1206                 errorf(&result->base.source_position,
1207                        "expression '%E' is not constant", result);
1208         }
1209
1210         return result;
1211 }
1212
1213 static expression_t *parse_assignment_expression(void)
1214 {
1215         return parse_sub_expression(PREC_ASSIGNMENT);
1216 }
1217
1218 static string_t parse_string_literals(void)
1219 {
1220         assert(token.type == T_STRING_LITERAL);
1221         string_t result = token.v.string;
1222
1223         next_token();
1224
1225         while (token.type == T_STRING_LITERAL) {
1226                 result = concat_strings(&result, &token.v.string);
1227                 next_token();
1228         }
1229
1230         return result;
1231 }
1232
1233 static const char *const gnu_attribute_names[GNU_AK_LAST] = {
1234         [GNU_AK_CONST]                  = "const",
1235         [GNU_AK_VOLATILE]               = "volatile",
1236         [GNU_AK_CDECL]                  = "cdecl",
1237         [GNU_AK_STDCALL]                = "stdcall",
1238         [GNU_AK_FASTCALL]               = "fastcall",
1239         [GNU_AK_DEPRECATED]             = "deprecated",
1240         [GNU_AK_NOINLINE]               = "noinline",
1241         [GNU_AK_RETURNS_TWICE]          = "returns_twice",
1242         [GNU_AK_NORETURN]               = "noreturn",
1243         [GNU_AK_NAKED]                  = "naked",
1244         [GNU_AK_PURE]                   = "pure",
1245         [GNU_AK_ALWAYS_INLINE]          = "always_inline",
1246         [GNU_AK_MALLOC]                 = "malloc",
1247         [GNU_AK_WEAK]                   = "weak",
1248         [GNU_AK_CONSTRUCTOR]            = "constructor",
1249         [GNU_AK_DESTRUCTOR]             = "destructor",
1250         [GNU_AK_NOTHROW]                = "nothrow",
1251         [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
1252         [GNU_AK_COMMON]                 = "common",
1253         [GNU_AK_NOCOMMON]               = "nocommon",
1254         [GNU_AK_PACKED]                 = "packed",
1255         [GNU_AK_SHARED]                 = "shared",
1256         [GNU_AK_NOTSHARED]              = "notshared",
1257         [GNU_AK_USED]                   = "used",
1258         [GNU_AK_UNUSED]                 = "unused",
1259         [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
1260         [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
1261         [GNU_AK_LONGCALL]               = "longcall",
1262         [GNU_AK_SHORTCALL]              = "shortcall",
1263         [GNU_AK_LONG_CALL]              = "long_call",
1264         [GNU_AK_SHORT_CALL]             = "short_call",
1265         [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
1266         [GNU_AK_INTERRUPT]              = "interrupt",
1267         [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
1268         [GNU_AK_NMI_HANDLER]            = "nmi_handler",
1269         [GNU_AK_NESTING]                = "nesting",
1270         [GNU_AK_NEAR]                   = "near",
1271         [GNU_AK_FAR]                    = "far",
1272         [GNU_AK_SIGNAL]                 = "signal",
1273         [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
1274         [GNU_AK_TINY_DATA]              = "tiny_data",
1275         [GNU_AK_SAVEALL]                = "saveall",
1276         [GNU_AK_FLATTEN]                = "flatten",
1277         [GNU_AK_SSEREGPARM]             = "sseregparm",
1278         [GNU_AK_EXTERNALLY_VISIBLE]     = "externally_visible",
1279         [GNU_AK_RETURN_TWICE]           = "return_twice",
1280         [GNU_AK_MAY_ALIAS]              = "may_alias",
1281         [GNU_AK_MS_STRUCT]              = "ms_struct",
1282         [GNU_AK_GCC_STRUCT]             = "gcc_struct",
1283         [GNU_AK_DLLIMPORT]              = "dllimport",
1284         [GNU_AK_DLLEXPORT]              = "dllexport",
1285         [GNU_AK_ALIGNED]                = "aligned",
1286         [GNU_AK_ALIAS]                  = "alias",
1287         [GNU_AK_SECTION]                = "section",
1288         [GNU_AK_FORMAT]                 = "format",
1289         [GNU_AK_FORMAT_ARG]             = "format_arg",
1290         [GNU_AK_WEAKREF]                = "weakref",
1291         [GNU_AK_NONNULL]                = "nonnull",
1292         [GNU_AK_TLS_MODEL]              = "tls_model",
1293         [GNU_AK_VISIBILITY]             = "visibility",
1294         [GNU_AK_REGPARM]                = "regparm",
1295         [GNU_AK_MODE]                   = "mode",
1296         [GNU_AK_MODEL]                  = "model",
1297         [GNU_AK_TRAP_EXIT]              = "trap_exit",
1298         [GNU_AK_SP_SWITCH]              = "sp_switch",
1299         [GNU_AK_SENTINEL]               = "sentinel"
1300 };
1301
1302 /**
1303  * compare two string, ignoring double underscores on the second.
1304  */
1305 static int strcmp_underscore(const char *s1, const char *s2)
1306 {
1307         if (s2[0] == '_' && s2[1] == '_') {
1308                 size_t len2 = strlen(s2);
1309                 size_t len1 = strlen(s1);
1310                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1311                         return strncmp(s1, s2+2, len2-4);
1312                 }
1313         }
1314
1315         return strcmp(s1, s2);
1316 }
1317
1318 /**
1319  * Allocate a new gnu temporal attribute of given kind.
1320  */
1321 static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
1322 {
1323         gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
1324         attribute->kind            = kind;
1325         attribute->next            = NULL;
1326         attribute->invalid         = false;
1327         attribute->has_arguments   = false;
1328
1329         return attribute;
1330 }
1331
1332 /**
1333  * Parse one constant expression argument of the given attribute.
1334  */
1335 static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
1336 {
1337         expression_t *expression;
1338         add_anchor_token(')');
1339         expression = parse_constant_expression();
1340         rem_anchor_token(')');
1341         expect(')', end_error);
1342         attribute->u.argument = fold_constant(expression);
1343         return;
1344 end_error:
1345         attribute->invalid = true;
1346 }
1347
1348 /**
1349  * Parse a list of constant expressions arguments of the given attribute.
1350  */
1351 static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
1352 {
1353         argument_list_t **list = &attribute->u.arguments;
1354         argument_list_t  *entry;
1355         expression_t     *expression;
1356         add_anchor_token(')');
1357         add_anchor_token(',');
1358         while (true) {
1359                 expression = parse_constant_expression();
1360                 entry = obstack_alloc(&temp_obst, sizeof(entry));
1361                 entry->argument = fold_constant(expression);
1362                 entry->next     = NULL;
1363                 *list = entry;
1364                 list = &entry->next;
1365                 if (token.type != ',')
1366                         break;
1367                 next_token();
1368         }
1369         rem_anchor_token(',');
1370         rem_anchor_token(')');
1371         expect(')', end_error);
1372         return;
1373 end_error:
1374         attribute->invalid = true;
1375 }
1376
1377 /**
1378  * Parse one string literal argument of the given attribute.
1379  */
1380 static void parse_gnu_attribute_string_arg(gnu_attribute_t *attribute,
1381                                            string_t *string)
1382 {
1383         add_anchor_token('(');
1384         if (token.type != T_STRING_LITERAL) {
1385                 parse_error_expected("while parsing attribute directive",
1386                                      T_STRING_LITERAL, NULL);
1387                 goto end_error;
1388         }
1389         *string = parse_string_literals();
1390         rem_anchor_token('(');
1391         expect(')', end_error);
1392         return;
1393 end_error:
1394         attribute->invalid = true;
1395 }
1396
1397 /**
1398  * Parse one tls model of the given attribute.
1399  */
1400 static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
1401 {
1402         static const char *const tls_models[] = {
1403                 "global-dynamic",
1404                 "local-dynamic",
1405                 "initial-exec",
1406                 "local-exec"
1407         };
1408         string_t string = { NULL, 0 };
1409         parse_gnu_attribute_string_arg(attribute, &string);
1410         if (string.begin != NULL) {
1411                 for (size_t i = 0; i < 4; ++i) {
1412                         if (strcmp(tls_models[i], string.begin) == 0) {
1413                                 attribute->u.value = i;
1414                                 return;
1415                         }
1416                 }
1417                 errorf(HERE, "'%s' is an unrecognized tls model", string.begin);
1418         }
1419         attribute->invalid = true;
1420 }
1421
1422 /**
1423  * Parse one tls model of the given attribute.
1424  */
1425 static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
1426 {
1427         static const char *const visibilities[] = {
1428                 "default",
1429                 "protected",
1430                 "hidden",
1431                 "internal"
1432         };
1433         string_t string = { NULL, 0 };
1434         parse_gnu_attribute_string_arg(attribute, &string);
1435         if (string.begin != NULL) {
1436                 for (size_t i = 0; i < 4; ++i) {
1437                         if (strcmp(visibilities[i], string.begin) == 0) {
1438                                 attribute->u.value = i;
1439                                 return;
1440                         }
1441                 }
1442                 errorf(HERE, "'%s' is an unrecognized visibility", string.begin);
1443         }
1444         attribute->invalid = true;
1445 }
1446
1447 /**
1448  * Parse one (code) model of the given attribute.
1449  */
1450 static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
1451 {
1452         static const char *const visibilities[] = {
1453                 "small",
1454                 "medium",
1455                 "large"
1456         };
1457         string_t string = { NULL, 0 };
1458         parse_gnu_attribute_string_arg(attribute, &string);
1459         if (string.begin != NULL) {
1460                 for (int i = 0; i < 3; ++i) {
1461                         if (strcmp(visibilities[i], string.begin) == 0) {
1462                                 attribute->u.value = i;
1463                                 return;
1464                         }
1465                 }
1466                 errorf(HERE, "'%s' is an unrecognized model", string.begin);
1467         }
1468         attribute->invalid = true;
1469 }
1470
1471 /**
1472  * Parse one mode of the given attribute.
1473  */
1474 static void parse_gnu_attribute_mode_arg(gnu_attribute_t *attribute)
1475 {
1476         add_anchor_token(')');
1477
1478         if (token.type != T_IDENTIFIER) {
1479                 expect(T_IDENTIFIER, end_error);
1480         }
1481
1482         attribute->u.symbol = token.v.symbol;
1483         next_token();
1484
1485         rem_anchor_token(')');
1486         expect(')', end_error);
1487         return;
1488 end_error:
1489         attribute->invalid = true;
1490 }
1491
1492 /**
1493  * Parse one interrupt argument of the given attribute.
1494  */
1495 static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
1496 {
1497         static const char *const interrupts[] = {
1498                 "IRQ",
1499                 "FIQ",
1500                 "SWI",
1501                 "ABORT",
1502                 "UNDEF"
1503         };
1504         string_t string = { NULL, 0 };
1505         parse_gnu_attribute_string_arg(attribute, &string);
1506         if (string.begin != NULL) {
1507                 for (size_t i = 0; i < 5; ++i) {
1508                         if (strcmp(interrupts[i], string.begin) == 0) {
1509                                 attribute->u.value = i;
1510                                 return;
1511                         }
1512                 }
1513                 errorf(HERE, "'%s' is not an interrupt", string.begin);
1514         }
1515         attribute->invalid = true;
1516 }
1517
1518 /**
1519  * Parse ( identifier, const expression, const expression )
1520  */
1521 static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
1522 {
1523         static const char *const format_names[] = {
1524                 "printf",
1525                 "scanf",
1526                 "strftime",
1527                 "strfmon"
1528         };
1529         int i;
1530
1531         if (token.type != T_IDENTIFIER) {
1532                 parse_error_expected("while parsing format attribute directive", T_IDENTIFIER, NULL);
1533                 goto end_error;
1534         }
1535         const char *name = token.v.symbol->string;
1536         for (i = 0; i < 4; ++i) {
1537                 if (strcmp_underscore(format_names[i], name) == 0)
1538                         break;
1539         }
1540         if (i >= 4) {
1541                 if (warning.attribute)
1542                         warningf(HERE, "'%s' is an unrecognized format function type", name);
1543         }
1544         next_token();
1545
1546         expect(',', end_error);
1547         add_anchor_token(')');
1548         add_anchor_token(',');
1549         parse_constant_expression();
1550         rem_anchor_token(',');
1551         rem_anchor_token(')');
1552
1553         expect(',', end_error);
1554         add_anchor_token(')');
1555         parse_constant_expression();
1556         rem_anchor_token(')');
1557         expect(')', end_error);
1558         return;
1559 end_error:
1560         attribute->u.value = true;
1561 }
1562
1563 /**
1564  * Check that a given GNU attribute has no arguments.
1565  */
1566 static void check_no_argument(gnu_attribute_t *attribute, const char *name)
1567 {
1568         if (!attribute->has_arguments)
1569                 return;
1570
1571         /* should have no arguments */
1572         errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1573         eat_until_matching_token('(');
1574         /* we have already consumed '(', so we stop before ')', eat it */
1575         next_token();
1576         attribute->invalid = true;
1577 }
1578
1579 /**
1580  * Parse one GNU attribute.
1581  *
1582  * Note that attribute names can be specified WITH or WITHOUT
1583  * double underscores, ie const or __const__.
1584  *
1585  * The following attributes are parsed without arguments
1586  *  const
1587  *  volatile
1588  *  cdecl
1589  *  stdcall
1590  *  fastcall
1591  *  deprecated
1592  *  noinline
1593  *  noreturn
1594  *  naked
1595  *  pure
1596  *  always_inline
1597  *  malloc
1598  *  weak
1599  *  constructor
1600  *  destructor
1601  *  nothrow
1602  *  transparent_union
1603  *  common
1604  *  nocommon
1605  *  packed
1606  *  shared
1607  *  notshared
1608  *  used
1609  *  unused
1610  *  no_instrument_function
1611  *  warn_unused_result
1612  *  longcall
1613  *  shortcall
1614  *  long_call
1615  *  short_call
1616  *  function_vector
1617  *  interrupt_handler
1618  *  nmi_handler
1619  *  nesting
1620  *  near
1621  *  far
1622  *  signal
1623  *  eightbit_data
1624  *  tiny_data
1625  *  saveall
1626  *  flatten
1627  *  sseregparm
1628  *  externally_visible
1629  *  return_twice
1630  *  may_alias
1631  *  ms_struct
1632  *  gcc_struct
1633  *  dllimport
1634  *  dllexport
1635  *
1636  * The following attributes are parsed with arguments
1637  *  aligned( const expression )
1638  *  alias( string literal )
1639  *  section( string literal )
1640  *  format( identifier, const expression, const expression )
1641  *  format_arg( const expression )
1642  *  tls_model( string literal )
1643  *  visibility( string literal )
1644  *  regparm( const expression )
1645  *  model( string leteral )
1646  *  trap_exit( const expression )
1647  *  sp_switch( string literal )
1648  *
1649  * The following attributes might have arguments
1650  *  weak_ref( string literal )
1651  *  non_null( const expression // ',' )
1652  *  interrupt( string literal )
1653  *  sentinel( constant expression )
1654  */
1655 static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
1656 {
1657         gnu_attribute_t *head      = *attributes;
1658         gnu_attribute_t *last      = *attributes;
1659         decl_modifiers_t modifiers = 0;
1660         gnu_attribute_t *attribute;
1661
1662         eat(T___attribute__);
1663         expect('(', end_error);
1664         expect('(', end_error);
1665
1666         if (token.type != ')') {
1667                 /* find the end of the list */
1668                 if (last != NULL) {
1669                         while (last->next != NULL)
1670                                 last = last->next;
1671                 }
1672
1673                 /* non-empty attribute list */
1674                 while (true) {
1675                         const char *name;
1676                         if (token.type == T_const) {
1677                                 name = "const";
1678                         } else if (token.type == T_volatile) {
1679                                 name = "volatile";
1680                         } else if (token.type == T_cdecl) {
1681                                 /* __attribute__((cdecl)), WITH ms mode */
1682                                 name = "cdecl";
1683                         } else if (token.type == T_IDENTIFIER) {
1684                                 const symbol_t *sym = token.v.symbol;
1685                                 name = sym->string;
1686                         } else {
1687                                 parse_error_expected("while parsing GNU attribute", T_IDENTIFIER, NULL);
1688                                 break;
1689                         }
1690
1691                         next_token();
1692
1693                         int i;
1694                         for (i = 0; i < GNU_AK_LAST; ++i) {
1695                                 if (strcmp_underscore(gnu_attribute_names[i], name) == 0)
1696                                         break;
1697                         }
1698                         gnu_attribute_kind_t kind = (gnu_attribute_kind_t)i;
1699
1700                         attribute = NULL;
1701                         if (kind == GNU_AK_LAST) {
1702                                 if (warning.attribute)
1703                                         warningf(HERE, "'%s' attribute directive ignored", name);
1704
1705                                 /* skip possible arguments */
1706                                 if (token.type == '(') {
1707                                         eat_until_matching_token(')');
1708                                         next_token(); /* skip the ')' */
1709                                 }
1710                         } else {
1711                                 /* check for arguments */
1712                                 attribute = allocate_gnu_attribute(kind);
1713                                 if (token.type == '(') {
1714                                         next_token();
1715                                         if (token.type == ')') {
1716                                                 /* empty args are allowed */
1717                                                 next_token();
1718                                         } else
1719                                                 attribute->has_arguments = true;
1720                                 }
1721
1722                                 switch (kind) {
1723                                 case GNU_AK_VOLATILE:
1724                                 case GNU_AK_NAKED:
1725                                 case GNU_AK_MALLOC:
1726                                 case GNU_AK_WEAK:
1727                                 case GNU_AK_COMMON:
1728                                 case GNU_AK_NOCOMMON:
1729                                 case GNU_AK_SHARED:
1730                                 case GNU_AK_NOTSHARED:
1731                                 case GNU_AK_NO_INSTRUMENT_FUNCTION:
1732                                 case GNU_AK_WARN_UNUSED_RESULT:
1733                                 case GNU_AK_LONGCALL:
1734                                 case GNU_AK_SHORTCALL:
1735                                 case GNU_AK_LONG_CALL:
1736                                 case GNU_AK_SHORT_CALL:
1737                                 case GNU_AK_FUNCTION_VECTOR:
1738                                 case GNU_AK_INTERRUPT_HANDLER:
1739                                 case GNU_AK_NMI_HANDLER:
1740                                 case GNU_AK_NESTING:
1741                                 case GNU_AK_NEAR:
1742                                 case GNU_AK_FAR:
1743                                 case GNU_AK_SIGNAL:
1744                                 case GNU_AK_EIGTHBIT_DATA:
1745                                 case GNU_AK_TINY_DATA:
1746                                 case GNU_AK_SAVEALL:
1747                                 case GNU_AK_FLATTEN:
1748                                 case GNU_AK_SSEREGPARM:
1749                                 case GNU_AK_EXTERNALLY_VISIBLE:
1750                                 case GNU_AK_RETURN_TWICE:
1751                                 case GNU_AK_MAY_ALIAS:
1752                                 case GNU_AK_MS_STRUCT:
1753                                 case GNU_AK_GCC_STRUCT:
1754                                         goto no_arg;
1755
1756                                 case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
1757                                 case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
1758                                 case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
1759                                 case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
1760                                 case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
1761                                 case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
1762                                 case GNU_AK_CONST:             modifiers |= DM_CONST;             goto no_arg;
1763                                 case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
1764                                 case GNU_AK_DLLIMPORT:         modifiers |= DM_DLLIMPORT;         goto no_arg;
1765                                 case GNU_AK_DLLEXPORT:         modifiers |= DM_DLLEXPORT;         goto no_arg;
1766                                 case GNU_AK_PACKED:            modifiers |= DM_PACKED;            goto no_arg;
1767                                 case GNU_AK_NOINLINE:          modifiers |= DM_NOINLINE;          goto no_arg;
1768                                 case GNU_AK_RETURNS_TWICE:     modifiers |= DM_RETURNS_TWICE;     goto no_arg;
1769                                 case GNU_AK_NORETURN:          modifiers |= DM_NORETURN;          goto no_arg;
1770                                 case GNU_AK_NOTHROW:           modifiers |= DM_NOTHROW;           goto no_arg;
1771                                 case GNU_AK_TRANSPARENT_UNION: modifiers |= DM_TRANSPARENT_UNION; goto no_arg;
1772                                 case GNU_AK_CONSTRUCTOR:       modifiers |= DM_CONSTRUCTOR;       goto no_arg;
1773                                 case GNU_AK_DESTRUCTOR:        modifiers |= DM_DESTRUCTOR;        goto no_arg;
1774                                 case GNU_AK_DEPRECATED:        modifiers |= DM_DEPRECATED;        goto no_arg;
1775
1776                                 case GNU_AK_ALIGNED:
1777                                         /* __align__ may be used without an argument */
1778                                         if (attribute->has_arguments) {
1779                                                 parse_gnu_attribute_const_arg(attribute);
1780                                         }
1781                                         break;
1782
1783                                 case GNU_AK_FORMAT_ARG:
1784                                 case GNU_AK_REGPARM:
1785                                 case GNU_AK_TRAP_EXIT:
1786                                         if (!attribute->has_arguments) {
1787                                                 /* should have arguments */
1788                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1789                                                 attribute->invalid = true;
1790                                         } else
1791                                                 parse_gnu_attribute_const_arg(attribute);
1792                                         break;
1793                                 case GNU_AK_ALIAS:
1794                                 case GNU_AK_SECTION:
1795                                 case GNU_AK_SP_SWITCH:
1796                                         if (!attribute->has_arguments) {
1797                                                 /* should have arguments */
1798                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1799                                                 attribute->invalid = true;
1800                                         } else
1801                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1802                                         break;
1803                                 case GNU_AK_FORMAT:
1804                                         if (!attribute->has_arguments) {
1805                                                 /* should have arguments */
1806                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1807                                                 attribute->invalid = true;
1808                                         } else
1809                                                 parse_gnu_attribute_format_args(attribute);
1810                                         break;
1811                                 case GNU_AK_WEAKREF:
1812                                         /* may have one string argument */
1813                                         if (attribute->has_arguments)
1814                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1815                                         break;
1816                                 case GNU_AK_NONNULL:
1817                                         if (attribute->has_arguments)
1818                                                 parse_gnu_attribute_const_arg_list(attribute);
1819                                         break;
1820                                 case GNU_AK_TLS_MODEL:
1821                                         if (!attribute->has_arguments) {
1822                                                 /* should have arguments */
1823                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1824                                         } else
1825                                                 parse_gnu_attribute_tls_model_arg(attribute);
1826                                         break;
1827                                 case GNU_AK_VISIBILITY:
1828                                         if (!attribute->has_arguments) {
1829                                                 /* should have arguments */
1830                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1831                                         } else
1832                                                 parse_gnu_attribute_visibility_arg(attribute);
1833                                         break;
1834                                 case GNU_AK_MODEL:
1835                                         if (!attribute->has_arguments) {
1836                                                 /* should have arguments */
1837                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1838                                         } else {
1839                                                 parse_gnu_attribute_model_arg(attribute);
1840                                         }
1841                                         break;
1842                                 case GNU_AK_MODE:
1843                                         if (!attribute->has_arguments) {
1844                                                 /* should have arguments */
1845                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1846                                         } else {
1847                                                 parse_gnu_attribute_mode_arg(attribute);
1848                                         }
1849                                         break;
1850                                 case GNU_AK_INTERRUPT:
1851                                         /* may have one string argument */
1852                                         if (attribute->has_arguments)
1853                                                 parse_gnu_attribute_interrupt_arg(attribute);
1854                                         break;
1855                                 case GNU_AK_SENTINEL:
1856                                         /* may have one string argument */
1857                                         if (attribute->has_arguments)
1858                                                 parse_gnu_attribute_const_arg(attribute);
1859                                         break;
1860                                 case GNU_AK_LAST:
1861                                         /* already handled */
1862                                         break;
1863
1864 no_arg:
1865                                         check_no_argument(attribute, name);
1866                                 }
1867                         }
1868                         if (attribute != NULL) {
1869                                 if (last != NULL) {
1870                                         last->next = attribute;
1871                                         last       = attribute;
1872                                 } else {
1873                                         head = last = attribute;
1874                                 }
1875                         }
1876
1877                         if (token.type != ',')
1878                                 break;
1879                         next_token();
1880                 }
1881         }
1882         expect(')', end_error);
1883         expect(')', end_error);
1884 end_error:
1885         *attributes = head;
1886
1887         return modifiers;
1888 }
1889
1890 /**
1891  * Parse GNU attributes.
1892  */
1893 static decl_modifiers_t parse_attributes(gnu_attribute_t **attributes)
1894 {
1895         decl_modifiers_t modifiers = 0;
1896
1897         while (true) {
1898                 switch (token.type) {
1899                 case T___attribute__:
1900                         modifiers |= parse_gnu_attribute(attributes);
1901                         continue;
1902
1903                 case T_asm:
1904                         next_token();
1905                         expect('(', end_error);
1906                         if (token.type != T_STRING_LITERAL) {
1907                                 parse_error_expected("while parsing assembler attribute",
1908                                                      T_STRING_LITERAL, NULL);
1909                                 eat_until_matching_token('(');
1910                                 break;
1911                         } else {
1912                                 parse_string_literals();
1913                         }
1914                         expect(')', end_error);
1915                         continue;
1916
1917                 case T_cdecl:     modifiers |= DM_CDECL;    break;
1918                 case T__fastcall: modifiers |= DM_FASTCALL; break;
1919                 case T__stdcall:  modifiers |= DM_STDCALL;  break;
1920
1921                 case T___thiscall:
1922                         /* TODO record modifier */
1923                         if (warning.other)
1924                                 warningf(HERE, "Ignoring declaration modifier %K", &token);
1925                         break;
1926
1927 end_error:
1928                 default: return modifiers;
1929                 }
1930
1931                 next_token();
1932         }
1933 }
1934
1935 static void mark_vars_read(expression_t *expr, entity_t *lhs_ent);
1936
1937 static entity_t *determine_lhs_ent(expression_t *const expr,
1938                                    entity_t *lhs_ent)
1939 {
1940         switch (expr->kind) {
1941                 case EXPR_REFERENCE: {
1942                         entity_t *const entity = expr->reference.entity;
1943                         /* we should only find variables as lvalues... */
1944                         if (entity->base.kind != ENTITY_VARIABLE
1945                                         && entity->base.kind != ENTITY_PARAMETER)
1946                                 return NULL;
1947
1948                         return entity;
1949                 }
1950
1951                 case EXPR_ARRAY_ACCESS: {
1952                         expression_t *const ref = expr->array_access.array_ref;
1953                         entity_t     *      ent = NULL;
1954                         if (is_type_array(skip_typeref(revert_automatic_type_conversion(ref)))) {
1955                                 ent     = determine_lhs_ent(ref, lhs_ent);
1956                                 lhs_ent = ent;
1957                         } else {
1958                                 mark_vars_read(expr->select.compound, lhs_ent);
1959                         }
1960                         mark_vars_read(expr->array_access.index, lhs_ent);
1961                         return ent;
1962                 }
1963
1964                 case EXPR_SELECT: {
1965                         if (is_type_compound(skip_typeref(expr->base.type))) {
1966                                 return determine_lhs_ent(expr->select.compound, lhs_ent);
1967                         } else {
1968                                 mark_vars_read(expr->select.compound, lhs_ent);
1969                                 return NULL;
1970                         }
1971                 }
1972
1973                 case EXPR_UNARY_DEREFERENCE: {
1974                         expression_t *const val = expr->unary.value;
1975                         if (val->kind == EXPR_UNARY_TAKE_ADDRESS) {
1976                                 /* *&x is a NOP */
1977                                 return determine_lhs_ent(val->unary.value, lhs_ent);
1978                         } else {
1979                                 mark_vars_read(val, NULL);
1980                                 return NULL;
1981                         }
1982                 }
1983
1984                 default:
1985                         mark_vars_read(expr, NULL);
1986                         return NULL;
1987         }
1988 }
1989
1990 #define ENT_ANY ((entity_t*)-1)
1991
1992 /**
1993  * Mark declarations, which are read.  This is used to detect variables, which
1994  * are never read.
1995  * Example:
1996  * x = x + 1;
1997  *   x is not marked as "read", because it is only read to calculate its own new
1998  *   value.
1999  *
2000  * x += y; y += x;
2001  *   x and y are not detected as "not read", because multiple variables are
2002  *   involved.
2003  */
2004 static void mark_vars_read(expression_t *const expr, entity_t *lhs_ent)
2005 {
2006         switch (expr->kind) {
2007                 case EXPR_REFERENCE: {
2008                         entity_t *const entity = expr->reference.entity;
2009                         if (entity->kind != ENTITY_VARIABLE
2010                                         && entity->kind != ENTITY_PARAMETER)
2011                                 return;
2012
2013                         if (lhs_ent != entity && lhs_ent != ENT_ANY) {
2014                                 if (entity->kind == ENTITY_VARIABLE) {
2015                                         entity->variable.read = true;
2016                                 } else {
2017                                         entity->parameter.read = true;
2018                                 }
2019                         }
2020                         return;
2021                 }
2022
2023                 case EXPR_CALL:
2024                         // TODO respect pure/const
2025                         mark_vars_read(expr->call.function, NULL);
2026                         for (call_argument_t *arg = expr->call.arguments; arg != NULL; arg = arg->next) {
2027                                 mark_vars_read(arg->expression, NULL);
2028                         }
2029                         return;
2030
2031                 case EXPR_CONDITIONAL:
2032                         // TODO lhs_decl should depend on whether true/false have an effect
2033                         mark_vars_read(expr->conditional.condition, NULL);
2034                         if (expr->conditional.true_expression != NULL)
2035                                 mark_vars_read(expr->conditional.true_expression, lhs_ent);
2036                         mark_vars_read(expr->conditional.false_expression, lhs_ent);
2037                         return;
2038
2039                 case EXPR_SELECT:
2040                         if (lhs_ent == ENT_ANY
2041                                         && !is_type_compound(skip_typeref(expr->base.type)))
2042                                 lhs_ent = NULL;
2043                         mark_vars_read(expr->select.compound, lhs_ent);
2044                         return;
2045
2046                 case EXPR_ARRAY_ACCESS: {
2047                         expression_t *const ref = expr->array_access.array_ref;
2048                         mark_vars_read(ref, lhs_ent);
2049                         lhs_ent = determine_lhs_ent(ref, lhs_ent);
2050                         mark_vars_read(expr->array_access.index, lhs_ent);
2051                         return;
2052                 }
2053
2054                 case EXPR_VA_ARG:
2055                         mark_vars_read(expr->va_arge.ap, lhs_ent);
2056                         return;
2057
2058                 case EXPR_VA_COPY:
2059                         mark_vars_read(expr->va_copye.src, lhs_ent);
2060                         return;
2061
2062                 case EXPR_UNARY_CAST:
2063                         /* Special case: Use void cast to mark a variable as "read" */
2064                         if (is_type_atomic(skip_typeref(expr->base.type), ATOMIC_TYPE_VOID))
2065                                 lhs_ent = NULL;
2066                         goto unary;
2067
2068
2069                 case EXPR_UNARY_THROW:
2070                         if (expr->unary.value == NULL)
2071                                 return;
2072                         /* FALLTHROUGH */
2073                 case EXPR_UNARY_DEREFERENCE:
2074                 case EXPR_UNARY_DELETE:
2075                 case EXPR_UNARY_DELETE_ARRAY:
2076                         if (lhs_ent == ENT_ANY)
2077                                 lhs_ent = NULL;
2078                         goto unary;
2079
2080                 case EXPR_UNARY_NEGATE:
2081                 case EXPR_UNARY_PLUS:
2082                 case EXPR_UNARY_BITWISE_NEGATE:
2083                 case EXPR_UNARY_NOT:
2084                 case EXPR_UNARY_TAKE_ADDRESS:
2085                 case EXPR_UNARY_POSTFIX_INCREMENT:
2086                 case EXPR_UNARY_POSTFIX_DECREMENT:
2087                 case EXPR_UNARY_PREFIX_INCREMENT:
2088                 case EXPR_UNARY_PREFIX_DECREMENT:
2089                 case EXPR_UNARY_CAST_IMPLICIT:
2090                 case EXPR_UNARY_ASSUME:
2091 unary:
2092                         mark_vars_read(expr->unary.value, lhs_ent);
2093                         return;
2094
2095                 case EXPR_BINARY_ADD:
2096                 case EXPR_BINARY_SUB:
2097                 case EXPR_BINARY_MUL:
2098                 case EXPR_BINARY_DIV:
2099                 case EXPR_BINARY_MOD:
2100                 case EXPR_BINARY_EQUAL:
2101                 case EXPR_BINARY_NOTEQUAL:
2102                 case EXPR_BINARY_LESS:
2103                 case EXPR_BINARY_LESSEQUAL:
2104                 case EXPR_BINARY_GREATER:
2105                 case EXPR_BINARY_GREATEREQUAL:
2106                 case EXPR_BINARY_BITWISE_AND:
2107                 case EXPR_BINARY_BITWISE_OR:
2108                 case EXPR_BINARY_BITWISE_XOR:
2109                 case EXPR_BINARY_LOGICAL_AND:
2110                 case EXPR_BINARY_LOGICAL_OR:
2111                 case EXPR_BINARY_SHIFTLEFT:
2112                 case EXPR_BINARY_SHIFTRIGHT:
2113                 case EXPR_BINARY_COMMA:
2114                 case EXPR_BINARY_ISGREATER:
2115                 case EXPR_BINARY_ISGREATEREQUAL:
2116                 case EXPR_BINARY_ISLESS:
2117                 case EXPR_BINARY_ISLESSEQUAL:
2118                 case EXPR_BINARY_ISLESSGREATER:
2119                 case EXPR_BINARY_ISUNORDERED:
2120                         mark_vars_read(expr->binary.left,  lhs_ent);
2121                         mark_vars_read(expr->binary.right, lhs_ent);
2122                         return;
2123
2124                 case EXPR_BINARY_ASSIGN:
2125                 case EXPR_BINARY_MUL_ASSIGN:
2126                 case EXPR_BINARY_DIV_ASSIGN:
2127                 case EXPR_BINARY_MOD_ASSIGN:
2128                 case EXPR_BINARY_ADD_ASSIGN:
2129                 case EXPR_BINARY_SUB_ASSIGN:
2130                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:
2131                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:
2132                 case EXPR_BINARY_BITWISE_AND_ASSIGN:
2133                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:
2134                 case EXPR_BINARY_BITWISE_OR_ASSIGN: {
2135                         if (lhs_ent == ENT_ANY)
2136                                 lhs_ent = NULL;
2137                         lhs_ent = determine_lhs_ent(expr->binary.left, lhs_ent);
2138                         mark_vars_read(expr->binary.right, lhs_ent);
2139                         return;
2140                 }
2141
2142                 case EXPR_VA_START:
2143                         determine_lhs_ent(expr->va_starte.ap, lhs_ent);
2144                         return;
2145
2146                 case EXPR_UNKNOWN:
2147                 case EXPR_INVALID:
2148                 case EXPR_CONST:
2149                 case EXPR_CHARACTER_CONSTANT:
2150                 case EXPR_WIDE_CHARACTER_CONSTANT:
2151                 case EXPR_STRING_LITERAL:
2152                 case EXPR_WIDE_STRING_LITERAL:
2153                 case EXPR_COMPOUND_LITERAL: // TODO init?
2154                 case EXPR_SIZEOF:
2155                 case EXPR_CLASSIFY_TYPE:
2156                 case EXPR_ALIGNOF:
2157                 case EXPR_FUNCNAME:
2158                 case EXPR_BUILTIN_CONSTANT_P:
2159                 case EXPR_BUILTIN_TYPES_COMPATIBLE_P:
2160                 case EXPR_OFFSETOF:
2161                 case EXPR_STATEMENT: // TODO
2162                 case EXPR_LABEL_ADDRESS:
2163                 case EXPR_REFERENCE_ENUM_VALUE:
2164                         return;
2165         }
2166
2167         panic("unhandled expression");
2168 }
2169
2170 static designator_t *parse_designation(void)
2171 {
2172         designator_t *result = NULL;
2173         designator_t *last   = NULL;
2174
2175         while (true) {
2176                 designator_t *designator;
2177                 switch (token.type) {
2178                 case '[':
2179                         designator = allocate_ast_zero(sizeof(designator[0]));
2180                         designator->source_position = token.source_position;
2181                         next_token();
2182                         add_anchor_token(']');
2183                         designator->array_index = parse_constant_expression();
2184                         rem_anchor_token(']');
2185                         expect(']', end_error);
2186                         break;
2187                 case '.':
2188                         designator = allocate_ast_zero(sizeof(designator[0]));
2189                         designator->source_position = token.source_position;
2190                         next_token();
2191                         if (token.type != T_IDENTIFIER) {
2192                                 parse_error_expected("while parsing designator",
2193                                                      T_IDENTIFIER, NULL);
2194                                 return NULL;
2195                         }
2196                         designator->symbol = token.v.symbol;
2197                         next_token();
2198                         break;
2199                 default:
2200                         expect('=', end_error);
2201                         return result;
2202                 }
2203
2204                 assert(designator != NULL);
2205                 if (last != NULL) {
2206                         last->next = designator;
2207                 } else {
2208                         result = designator;
2209                 }
2210                 last = designator;
2211         }
2212 end_error:
2213         return NULL;
2214 }
2215
2216 static initializer_t *initializer_from_string(array_type_t *type,
2217                                               const string_t *const string)
2218 {
2219         /* TODO: check len vs. size of array type */
2220         (void) type;
2221
2222         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
2223         initializer->string.string = *string;
2224
2225         return initializer;
2226 }
2227
2228 static initializer_t *initializer_from_wide_string(array_type_t *const type,
2229                                                    wide_string_t *const string)
2230 {
2231         /* TODO: check len vs. size of array type */
2232         (void) type;
2233
2234         initializer_t *const initializer =
2235                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
2236         initializer->wide_string.string = *string;
2237
2238         return initializer;
2239 }
2240
2241 /**
2242  * Build an initializer from a given expression.
2243  */
2244 static initializer_t *initializer_from_expression(type_t *orig_type,
2245                                                   expression_t *expression)
2246 {
2247         /* TODO check that expression is a constant expression */
2248
2249         /* §6.7.8.14/15 char array may be initialized by string literals */
2250         type_t *type           = skip_typeref(orig_type);
2251         type_t *expr_type_orig = expression->base.type;
2252         type_t *expr_type      = skip_typeref(expr_type_orig);
2253         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
2254                 array_type_t *const array_type   = &type->array;
2255                 type_t       *const element_type = skip_typeref(array_type->element_type);
2256
2257                 if (element_type->kind == TYPE_ATOMIC) {
2258                         atomic_type_kind_t akind = element_type->atomic.akind;
2259                         switch (expression->kind) {
2260                                 case EXPR_STRING_LITERAL:
2261                                         if (akind == ATOMIC_TYPE_CHAR
2262                                                         || akind == ATOMIC_TYPE_SCHAR
2263                                                         || akind == ATOMIC_TYPE_UCHAR) {
2264                                                 return initializer_from_string(array_type,
2265                                                         &expression->string.value);
2266                                         }
2267                                         break;
2268
2269                                 case EXPR_WIDE_STRING_LITERAL: {
2270                                         type_t *bare_wchar_type = skip_typeref(type_wchar_t);
2271                                         if (get_unqualified_type(element_type) == bare_wchar_type) {
2272                                                 return initializer_from_wide_string(array_type,
2273                                                         &expression->wide_string.value);
2274                                         }
2275                                         break;
2276                                 }
2277
2278                                 default:
2279                                         break;
2280                         }
2281                 }
2282         }
2283
2284         assign_error_t error = semantic_assign(type, expression);
2285         if (error == ASSIGN_ERROR_INCOMPATIBLE)
2286                 return NULL;
2287         report_assign_error(error, type, expression, "initializer",
2288                             &expression->base.source_position);
2289
2290         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
2291 #if 0
2292         if (type->kind == TYPE_BITFIELD) {
2293                 type = type->bitfield.base_type;
2294         }
2295 #endif
2296         result->value.value = create_implicit_cast(expression, type);
2297
2298         return result;
2299 }
2300
2301 /**
2302  * Checks if a given expression can be used as an constant initializer.
2303  */
2304 static bool is_initializer_constant(const expression_t *expression)
2305 {
2306         return is_constant_expression(expression)
2307                 || is_address_constant(expression);
2308 }
2309
2310 /**
2311  * Parses an scalar initializer.
2312  *
2313  * §6.7.8.11; eat {} without warning
2314  */
2315 static initializer_t *parse_scalar_initializer(type_t *type,
2316                                                bool must_be_constant)
2317 {
2318         /* there might be extra {} hierarchies */
2319         int braces = 0;
2320         if (token.type == '{') {
2321                 if (warning.other)
2322                         warningf(HERE, "extra curly braces around scalar initializer");
2323                 do {
2324                         ++braces;
2325                         next_token();
2326                 } while (token.type == '{');
2327         }
2328
2329         expression_t *expression = parse_assignment_expression();
2330         mark_vars_read(expression, NULL);
2331         if (must_be_constant && !is_initializer_constant(expression)) {
2332                 errorf(&expression->base.source_position,
2333                        "Initialisation expression '%E' is not constant",
2334                        expression);
2335         }
2336
2337         initializer_t *initializer = initializer_from_expression(type, expression);
2338
2339         if (initializer == NULL) {
2340                 errorf(&expression->base.source_position,
2341                        "expression '%E' (type '%T') doesn't match expected type '%T'",
2342                        expression, expression->base.type, type);
2343                 /* TODO */
2344                 return NULL;
2345         }
2346
2347         bool additional_warning_displayed = false;
2348         while (braces > 0) {
2349                 if (token.type == ',') {
2350                         next_token();
2351                 }
2352                 if (token.type != '}') {
2353                         if (!additional_warning_displayed && warning.other) {
2354                                 warningf(HERE, "additional elements in scalar initializer");
2355                                 additional_warning_displayed = true;
2356                         }
2357                 }
2358                 eat_block();
2359                 braces--;
2360         }
2361
2362         return initializer;
2363 }
2364
2365 /**
2366  * An entry in the type path.
2367  */
2368 typedef struct type_path_entry_t type_path_entry_t;
2369 struct type_path_entry_t {
2370         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
2371         union {
2372                 size_t         index;          /**< For array types: the current index. */
2373                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
2374         } v;
2375 };
2376
2377 /**
2378  * A type path expression a position inside compound or array types.
2379  */
2380 typedef struct type_path_t type_path_t;
2381 struct type_path_t {
2382         type_path_entry_t *path;         /**< An flexible array containing the current path. */
2383         type_t            *top_type;     /**< type of the element the path points */
2384         size_t             max_index;    /**< largest index in outermost array */
2385 };
2386
2387 /**
2388  * Prints a type path for debugging.
2389  */
2390 static __attribute__((unused)) void debug_print_type_path(
2391                 const type_path_t *path)
2392 {
2393         size_t len = ARR_LEN(path->path);
2394
2395         for (size_t i = 0; i < len; ++i) {
2396                 const type_path_entry_t *entry = & path->path[i];
2397
2398                 type_t *type = skip_typeref(entry->type);
2399                 if (is_type_compound(type)) {
2400                         /* in gcc mode structs can have no members */
2401                         if (entry->v.compound_entry == NULL) {
2402                                 assert(i == len-1);
2403                                 continue;
2404                         }
2405                         fprintf(stderr, ".%s",
2406                                 entry->v.compound_entry->base.symbol->string);
2407                 } else if (is_type_array(type)) {
2408                         fprintf(stderr, "[%u]", (unsigned) entry->v.index);
2409                 } else {
2410                         fprintf(stderr, "-INVALID-");
2411                 }
2412         }
2413         if (path->top_type != NULL) {
2414                 fprintf(stderr, "  (");
2415                 print_type(path->top_type);
2416                 fprintf(stderr, ")");
2417         }
2418 }
2419
2420 /**
2421  * Return the top type path entry, ie. in a path
2422  * (type).a.b returns the b.
2423  */
2424 static type_path_entry_t *get_type_path_top(const type_path_t *path)
2425 {
2426         size_t len = ARR_LEN(path->path);
2427         assert(len > 0);
2428         return &path->path[len-1];
2429 }
2430
2431 /**
2432  * Enlarge the type path by an (empty) element.
2433  */
2434 static type_path_entry_t *append_to_type_path(type_path_t *path)
2435 {
2436         size_t len = ARR_LEN(path->path);
2437         ARR_RESIZE(type_path_entry_t, path->path, len+1);
2438
2439         type_path_entry_t *result = & path->path[len];
2440         memset(result, 0, sizeof(result[0]));
2441         return result;
2442 }
2443
2444 /**
2445  * Descending into a sub-type. Enter the scope of the current top_type.
2446  */
2447 static void descend_into_subtype(type_path_t *path)
2448 {
2449         type_t *orig_top_type = path->top_type;
2450         type_t *top_type      = skip_typeref(orig_top_type);
2451
2452         type_path_entry_t *top = append_to_type_path(path);
2453         top->type              = top_type;
2454
2455         if (is_type_compound(top_type)) {
2456                 compound_t *compound  = top_type->compound.compound;
2457                 entity_t   *entry     = compound->members.entities;
2458
2459                 if (entry != NULL) {
2460                         assert(entry->kind == ENTITY_COMPOUND_MEMBER);
2461                         top->v.compound_entry = &entry->declaration;
2462                         path->top_type = entry->declaration.type;
2463                 } else {
2464                         path->top_type = NULL;
2465                 }
2466         } else if (is_type_array(top_type)) {
2467                 top->v.index   = 0;
2468                 path->top_type = top_type->array.element_type;
2469         } else {
2470                 assert(!is_type_valid(top_type));
2471         }
2472 }
2473
2474 /**
2475  * Pop an entry from the given type path, ie. returning from
2476  * (type).a.b to (type).a
2477  */
2478 static void ascend_from_subtype(type_path_t *path)
2479 {
2480         type_path_entry_t *top = get_type_path_top(path);
2481
2482         path->top_type = top->type;
2483
2484         size_t len = ARR_LEN(path->path);
2485         ARR_RESIZE(type_path_entry_t, path->path, len-1);
2486 }
2487
2488 /**
2489  * Pop entries from the given type path until the given
2490  * path level is reached.
2491  */
2492 static void ascend_to(type_path_t *path, size_t top_path_level)
2493 {
2494         size_t len = ARR_LEN(path->path);
2495
2496         while (len > top_path_level) {
2497                 ascend_from_subtype(path);
2498                 len = ARR_LEN(path->path);
2499         }
2500 }
2501
2502 static bool walk_designator(type_path_t *path, const designator_t *designator,
2503                             bool used_in_offsetof)
2504 {
2505         for (; designator != NULL; designator = designator->next) {
2506                 type_path_entry_t *top       = get_type_path_top(path);
2507                 type_t            *orig_type = top->type;
2508
2509                 type_t *type = skip_typeref(orig_type);
2510
2511                 if (designator->symbol != NULL) {
2512                         symbol_t *symbol = designator->symbol;
2513                         if (!is_type_compound(type)) {
2514                                 if (is_type_valid(type)) {
2515                                         errorf(&designator->source_position,
2516                                                "'.%Y' designator used for non-compound type '%T'",
2517                                                symbol, orig_type);
2518                                 }
2519
2520                                 top->type             = type_error_type;
2521                                 top->v.compound_entry = NULL;
2522                                 orig_type             = type_error_type;
2523                         } else {
2524                                 compound_t *compound = type->compound.compound;
2525                                 entity_t   *iter     = compound->members.entities;
2526                                 for (; iter != NULL; iter = iter->base.next) {
2527                                         if (iter->base.symbol == symbol) {
2528                                                 break;
2529                                         }
2530                                 }
2531                                 if (iter == NULL) {
2532                                         errorf(&designator->source_position,
2533                                                "'%T' has no member named '%Y'", orig_type, symbol);
2534                                         goto failed;
2535                                 }
2536                                 assert(iter->kind == ENTITY_COMPOUND_MEMBER);
2537                                 if (used_in_offsetof) {
2538                                         type_t *real_type = skip_typeref(iter->declaration.type);
2539                                         if (real_type->kind == TYPE_BITFIELD) {
2540                                                 errorf(&designator->source_position,
2541                                                        "offsetof designator '%Y' may not specify bitfield",
2542                                                        symbol);
2543                                                 goto failed;
2544                                         }
2545                                 }
2546
2547                                 top->type             = orig_type;
2548                                 top->v.compound_entry = &iter->declaration;
2549                                 orig_type             = iter->declaration.type;
2550                         }
2551                 } else {
2552                         expression_t *array_index = designator->array_index;
2553                         assert(designator->array_index != NULL);
2554
2555                         if (!is_type_array(type)) {
2556                                 if (is_type_valid(type)) {
2557                                         errorf(&designator->source_position,
2558                                                "[%E] designator used for non-array type '%T'",
2559                                                array_index, orig_type);
2560                                 }
2561                                 goto failed;
2562                         }
2563
2564                         long index = fold_constant(array_index);
2565                         if (!used_in_offsetof) {
2566                                 if (index < 0) {
2567                                         errorf(&designator->source_position,
2568                                                "array index [%E] must be positive", array_index);
2569                                 } else if (type->array.size_constant) {
2570                                         long array_size = type->array.size;
2571                                         if (index >= array_size) {
2572                                                 errorf(&designator->source_position,
2573                                                        "designator [%E] (%d) exceeds array size %d",
2574                                                        array_index, index, array_size);
2575                                         }
2576                                 }
2577                         }
2578
2579                         top->type    = orig_type;
2580                         top->v.index = (size_t) index;
2581                         orig_type    = type->array.element_type;
2582                 }
2583                 path->top_type = orig_type;
2584
2585                 if (designator->next != NULL) {
2586                         descend_into_subtype(path);
2587                 }
2588         }
2589         return true;
2590
2591 failed:
2592         return false;
2593 }
2594
2595 static void advance_current_object(type_path_t *path, size_t top_path_level)
2596 {
2597         type_path_entry_t *top = get_type_path_top(path);
2598
2599         type_t *type = skip_typeref(top->type);
2600         if (is_type_union(type)) {
2601                 /* in unions only the first element is initialized */
2602                 top->v.compound_entry = NULL;
2603         } else if (is_type_struct(type)) {
2604                 declaration_t *entry = top->v.compound_entry;
2605
2606                 entity_t *next_entity = entry->base.next;
2607                 if (next_entity != NULL) {
2608                         assert(is_declaration(next_entity));
2609                         entry = &next_entity->declaration;
2610                 } else {
2611                         entry = NULL;
2612                 }
2613
2614                 top->v.compound_entry = entry;
2615                 if (entry != NULL) {
2616                         path->top_type = entry->type;
2617                         return;
2618                 }
2619         } else if (is_type_array(type)) {
2620                 assert(is_type_array(type));
2621
2622                 top->v.index++;
2623
2624                 if (!type->array.size_constant || top->v.index < type->array.size) {
2625                         return;
2626                 }
2627         } else {
2628                 assert(!is_type_valid(type));
2629                 return;
2630         }
2631
2632         /* we're past the last member of the current sub-aggregate, try if we
2633          * can ascend in the type hierarchy and continue with another subobject */
2634         size_t len = ARR_LEN(path->path);
2635
2636         if (len > top_path_level) {
2637                 ascend_from_subtype(path);
2638                 advance_current_object(path, top_path_level);
2639         } else {
2640                 path->top_type = NULL;
2641         }
2642 }
2643
2644 /**
2645  * skip until token is found.
2646  */
2647 static void skip_until(int type)
2648 {
2649         while (token.type != type) {
2650                 if (token.type == T_EOF)
2651                         return;
2652                 next_token();
2653         }
2654 }
2655
2656 /**
2657  * skip any {...} blocks until a closing bracket is reached.
2658  */
2659 static void skip_initializers(void)
2660 {
2661         if (token.type == '{')
2662                 next_token();
2663
2664         while (token.type != '}') {
2665                 if (token.type == T_EOF)
2666                         return;
2667                 if (token.type == '{') {
2668                         eat_block();
2669                         continue;
2670                 }
2671                 next_token();
2672         }
2673 }
2674
2675 static initializer_t *create_empty_initializer(void)
2676 {
2677         static initializer_t empty_initializer
2678                 = { .list = { { INITIALIZER_LIST }, 0 } };
2679         return &empty_initializer;
2680 }
2681
2682 /**
2683  * Parse a part of an initialiser for a struct or union,
2684  */
2685 static initializer_t *parse_sub_initializer(type_path_t *path,
2686                 type_t *outer_type, size_t top_path_level,
2687                 parse_initializer_env_t *env)
2688 {
2689         if (token.type == '}') {
2690                 /* empty initializer */
2691                 return create_empty_initializer();
2692         }
2693
2694         type_t *orig_type = path->top_type;
2695         type_t *type      = NULL;
2696
2697         if (orig_type == NULL) {
2698                 /* We are initializing an empty compound. */
2699         } else {
2700                 type = skip_typeref(orig_type);
2701         }
2702
2703         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2704
2705         while (true) {
2706                 designator_t *designator = NULL;
2707                 if (token.type == '.' || token.type == '[') {
2708                         designator = parse_designation();
2709                         goto finish_designator;
2710                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2711                         /* GNU-style designator ("identifier: value") */
2712                         designator = allocate_ast_zero(sizeof(designator[0]));
2713                         designator->source_position = token.source_position;
2714                         designator->symbol          = token.v.symbol;
2715                         eat(T_IDENTIFIER);
2716                         eat(':');
2717
2718 finish_designator:
2719                         /* reset path to toplevel, evaluate designator from there */
2720                         ascend_to(path, top_path_level);
2721                         if (!walk_designator(path, designator, false)) {
2722                                 /* can't continue after designation error */
2723                                 goto end_error;
2724                         }
2725
2726                         initializer_t *designator_initializer
2727                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2728                         designator_initializer->designator.designator = designator;
2729                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2730
2731                         orig_type = path->top_type;
2732                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2733                 }
2734
2735                 initializer_t *sub;
2736
2737                 if (token.type == '{') {
2738                         if (type != NULL && is_type_scalar(type)) {
2739                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2740                         } else {
2741                                 eat('{');
2742                                 if (type == NULL) {
2743                                         if (env->entity != NULL) {
2744                                                 errorf(HERE,
2745                                                      "extra brace group at end of initializer for '%Y'",
2746                                                      env->entity->base.symbol);
2747                                         } else {
2748                                                 errorf(HERE, "extra brace group at end of initializer");
2749                                         }
2750                                 } else
2751                                         descend_into_subtype(path);
2752
2753                                 add_anchor_token('}');
2754                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2755                                                             env);
2756                                 rem_anchor_token('}');
2757
2758                                 if (type != NULL) {
2759                                         ascend_from_subtype(path);
2760                                         expect('}', end_error);
2761                                 } else {
2762                                         expect('}', end_error);
2763                                         goto error_parse_next;
2764                                 }
2765                         }
2766                 } else {
2767                         /* must be an expression */
2768                         expression_t *expression = parse_assignment_expression();
2769                         mark_vars_read(expression, NULL);
2770
2771                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2772                                 errorf(&expression->base.source_position,
2773                                        "Initialisation expression '%E' is not constant",
2774                                        expression);
2775                         }
2776
2777                         if (type == NULL) {
2778                                 /* we are already outside, ... */
2779                                 type_t *const outer_type_skip = skip_typeref(outer_type);
2780                                 if (is_type_compound(outer_type_skip) &&
2781                                     !outer_type_skip->compound.compound->complete) {
2782                                         goto error_parse_next;
2783                                 }
2784                                 goto error_excess;
2785                         }
2786
2787                         /* handle { "string" } special case */
2788                         if ((expression->kind == EXPR_STRING_LITERAL
2789                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2790                                         && outer_type != NULL) {
2791                                 sub = initializer_from_expression(outer_type, expression);
2792                                 if (sub != NULL) {
2793                                         if (token.type == ',') {
2794                                                 next_token();
2795                                         }
2796                                         if (token.type != '}' && warning.other) {
2797                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2798                                                                  orig_type);
2799                                         }
2800                                         /* TODO: eat , ... */
2801                                         return sub;
2802                                 }
2803                         }
2804
2805                         /* descend into subtypes until expression matches type */
2806                         while (true) {
2807                                 orig_type = path->top_type;
2808                                 type      = skip_typeref(orig_type);
2809
2810                                 sub = initializer_from_expression(orig_type, expression);
2811                                 if (sub != NULL) {
2812                                         break;
2813                                 }
2814                                 if (!is_type_valid(type)) {
2815                                         goto end_error;
2816                                 }
2817                                 if (is_type_scalar(type)) {
2818                                         errorf(&expression->base.source_position,
2819                                                         "expression '%E' doesn't match expected type '%T'",
2820                                                         expression, orig_type);
2821                                         goto end_error;
2822                                 }
2823
2824                                 descend_into_subtype(path);
2825                         }
2826                 }
2827
2828                 /* update largest index of top array */
2829                 const type_path_entry_t *first      = &path->path[0];
2830                 type_t                  *first_type = first->type;
2831                 first_type                          = skip_typeref(first_type);
2832                 if (is_type_array(first_type)) {
2833                         size_t index = first->v.index;
2834                         if (index > path->max_index)
2835                                 path->max_index = index;
2836                 }
2837
2838                 if (type != NULL) {
2839                         /* append to initializers list */
2840                         ARR_APP1(initializer_t*, initializers, sub);
2841                 } else {
2842 error_excess:
2843                         if (warning.other) {
2844                                 if (env->entity != NULL) {
2845                                         warningf(HERE, "excess elements in struct initializer for '%Y'",
2846                                            env->entity->base.symbol);
2847                                 } else {
2848                                         warningf(HERE, "excess elements in struct initializer");
2849                                 }
2850                         }
2851                 }
2852
2853 error_parse_next:
2854                 if (token.type == '}') {
2855                         break;
2856                 }
2857                 expect(',', end_error);
2858                 if (token.type == '}') {
2859                         break;
2860                 }
2861
2862                 if (type != NULL) {
2863                         /* advance to the next declaration if we are not at the end */
2864                         advance_current_object(path, top_path_level);
2865                         orig_type = path->top_type;
2866                         if (orig_type != NULL)
2867                                 type = skip_typeref(orig_type);
2868                         else
2869                                 type = NULL;
2870                 }
2871         }
2872
2873         size_t len  = ARR_LEN(initializers);
2874         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2875         initializer_t *result = allocate_ast_zero(size);
2876         result->kind          = INITIALIZER_LIST;
2877         result->list.len      = len;
2878         memcpy(&result->list.initializers, initializers,
2879                len * sizeof(initializers[0]));
2880
2881         DEL_ARR_F(initializers);
2882         ascend_to(path, top_path_level+1);
2883
2884         return result;
2885
2886 end_error:
2887         skip_initializers();
2888         DEL_ARR_F(initializers);
2889         ascend_to(path, top_path_level+1);
2890         return NULL;
2891 }
2892
2893 /**
2894  * Parses an initializer. Parsers either a compound literal
2895  * (env->declaration == NULL) or an initializer of a declaration.
2896  */
2897 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2898 {
2899         type_t        *type      = skip_typeref(env->type);
2900         size_t         max_index = 0xdeadbeaf;   // TODO: Resolve this uninitialized variable problem
2901         initializer_t *result;
2902
2903         if (is_type_scalar(type)) {
2904                 result = parse_scalar_initializer(type, env->must_be_constant);
2905         } else if (token.type == '{') {
2906                 eat('{');
2907
2908                 type_path_t path;
2909                 memset(&path, 0, sizeof(path));
2910                 path.top_type = env->type;
2911                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2912
2913                 descend_into_subtype(&path);
2914
2915                 add_anchor_token('}');
2916                 result = parse_sub_initializer(&path, env->type, 1, env);
2917                 rem_anchor_token('}');
2918
2919                 max_index = path.max_index;
2920                 DEL_ARR_F(path.path);
2921
2922                 expect('}', end_error);
2923         } else {
2924                 /* parse_scalar_initializer() also works in this case: we simply
2925                  * have an expression without {} around it */
2926                 result = parse_scalar_initializer(type, env->must_be_constant);
2927         }
2928
2929         /* §6.7.8:22 array initializers for arrays with unknown size determine
2930          * the array type size */
2931         if (is_type_array(type) && type->array.size_expression == NULL
2932                         && result != NULL) {
2933                 size_t size;
2934                 switch (result->kind) {
2935                 case INITIALIZER_LIST:
2936                         assert(max_index != 0xdeadbeaf);
2937                         size = max_index + 1;
2938                         break;
2939
2940                 case INITIALIZER_STRING:
2941                         size = result->string.string.size;
2942                         break;
2943
2944                 case INITIALIZER_WIDE_STRING:
2945                         size = result->wide_string.string.size;
2946                         break;
2947
2948                 case INITIALIZER_DESIGNATOR:
2949                 case INITIALIZER_VALUE:
2950                         /* can happen for parse errors */
2951                         size = 0;
2952                         break;
2953
2954                 default:
2955                         internal_errorf(HERE, "invalid initializer type");
2956                 }
2957
2958                 expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2959                 cnst->base.type          = type_size_t;
2960                 cnst->conste.v.int_value = size;
2961
2962                 type_t *new_type = duplicate_type(type);
2963
2964                 new_type->array.size_expression   = cnst;
2965                 new_type->array.size_constant     = true;
2966                 new_type->array.has_implicit_size = true;
2967                 new_type->array.size              = size;
2968                 env->type = new_type;
2969         }
2970
2971         return result;
2972 end_error:
2973         return NULL;
2974 }
2975
2976 static void append_entity(scope_t *scope, entity_t *entity)
2977 {
2978         if (scope->last_entity != NULL) {
2979                 scope->last_entity->base.next = entity;
2980         } else {
2981                 scope->entities = entity;
2982         }
2983         scope->last_entity = entity;
2984 }
2985
2986
2987 static compound_t *parse_compound_type_specifier(bool is_struct)
2988 {
2989         gnu_attribute_t  *attributes = NULL;
2990         decl_modifiers_t  modifiers  = 0;
2991         if (is_struct) {
2992                 eat(T_struct);
2993         } else {
2994                 eat(T_union);
2995         }
2996
2997         symbol_t   *symbol   = NULL;
2998         compound_t *compound = NULL;
2999
3000         if (token.type == T___attribute__) {
3001                 modifiers |= parse_attributes(&attributes);
3002         }
3003
3004         entity_kind_tag_t const kind = is_struct ? ENTITY_STRUCT : ENTITY_UNION;
3005         if (token.type == T_IDENTIFIER) {
3006                 /* the compound has a name, check if we have seen it already */
3007                 symbol = token.v.symbol;
3008                 next_token();
3009
3010                 entity_t *entity = get_tag(symbol, kind);
3011                 if (entity != NULL) {
3012                         compound = &entity->compound;
3013                         if (compound->base.parent_scope != current_scope &&
3014                             (token.type == '{' || token.type == ';')) {
3015                                 /* we're in an inner scope and have a definition. Shadow
3016                                  * existing definition in outer scope */
3017                                 compound = NULL;
3018                         } else if (compound->complete && token.type == '{') {
3019                                 assert(symbol != NULL);
3020                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition %P)",
3021                                        is_struct ? "struct" : "union", symbol,
3022                                        &compound->base.source_position);
3023                                 /* clear members in the hope to avoid further errors */
3024                                 compound->members.entities = NULL;
3025                         }
3026                 }
3027         } else if (token.type != '{') {
3028                 if (is_struct) {
3029                         parse_error_expected("while parsing struct type specifier",
3030                                              T_IDENTIFIER, '{', NULL);
3031                 } else {
3032                         parse_error_expected("while parsing union type specifier",
3033                                              T_IDENTIFIER, '{', NULL);
3034                 }
3035
3036                 return NULL;
3037         }
3038
3039         if (compound == NULL) {
3040                 entity_t *entity = allocate_entity_zero(kind);
3041                 compound         = &entity->compound;
3042
3043                 compound->base.namespc         = NAMESPACE_TAG;
3044                 compound->base.source_position = token.source_position;
3045                 compound->base.symbol          = symbol;
3046                 compound->base.parent_scope    = current_scope;
3047                 if (symbol != NULL) {
3048                         environment_push(entity);
3049                 }
3050                 append_entity(current_scope, entity);
3051         }
3052
3053         if (token.type == '{') {
3054                 parse_compound_type_entries(compound);
3055                 modifiers |= parse_attributes(&attributes);
3056
3057                 /* ISO/IEC 14882:1998(E) §7.1.3:5 */
3058                 if (symbol == NULL) {
3059                         assert(anonymous_entity == NULL);
3060                         anonymous_entity = (entity_t*)compound;
3061                 }
3062         }
3063
3064         compound->modifiers |= modifiers;
3065         return compound;
3066 }
3067
3068 static void parse_enum_entries(type_t *const enum_type)
3069 {
3070         eat('{');
3071
3072         if (token.type == '}') {
3073                 errorf(HERE, "empty enum not allowed");
3074                 next_token();
3075                 return;
3076         }
3077
3078         add_anchor_token('}');
3079         do {
3080                 if (token.type != T_IDENTIFIER) {
3081                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
3082                         eat_block();
3083                         rem_anchor_token('}');
3084                         return;
3085                 }
3086
3087                 entity_t *entity             = allocate_entity_zero(ENTITY_ENUM_VALUE);
3088                 entity->enum_value.enum_type = enum_type;
3089                 entity->base.symbol          = token.v.symbol;
3090                 entity->base.source_position = token.source_position;
3091                 next_token();
3092
3093                 if (token.type == '=') {
3094                         next_token();
3095                         expression_t *value = parse_constant_expression();
3096
3097                         value = create_implicit_cast(value, enum_type);
3098                         entity->enum_value.value = value;
3099
3100                         /* TODO semantic */
3101                 }
3102
3103                 record_entity(entity, false);
3104
3105                 if (token.type != ',')
3106                         break;
3107                 next_token();
3108         } while (token.type != '}');
3109         rem_anchor_token('}');
3110
3111         expect('}', end_error);
3112
3113 end_error:
3114         ;
3115 }
3116
3117 static type_t *parse_enum_specifier(void)
3118 {
3119         gnu_attribute_t *attributes = NULL;
3120         entity_t        *entity;
3121         symbol_t        *symbol;
3122
3123         eat(T_enum);
3124         if (token.type == T_IDENTIFIER) {
3125                 symbol = token.v.symbol;
3126                 next_token();
3127
3128                 entity = get_tag(symbol, ENTITY_ENUM);
3129                 if (entity != NULL) {
3130                         if (entity->base.parent_scope != current_scope &&
3131                                         (token.type == '{' || token.type == ';')) {
3132                                 /* we're in an inner scope and have a definition. Shadow
3133                                  * existing definition in outer scope */
3134                                 entity = NULL;
3135                         } else if (entity->enume.complete && token.type == '{') {
3136                                 errorf(HERE, "multiple definitions of 'enum %Y' (previous definition %P)",
3137                                                 symbol, &entity->base.source_position);
3138                         }
3139                 }
3140         } else if (token.type != '{') {
3141                 parse_error_expected("while parsing enum type specifier",
3142                                      T_IDENTIFIER, '{', NULL);
3143                 return NULL;
3144         } else {
3145                 entity  = NULL;
3146                 symbol  = NULL;
3147         }
3148
3149         if (entity == NULL) {
3150                 entity                       = allocate_entity_zero(ENTITY_ENUM);
3151                 entity->base.namespc         = NAMESPACE_TAG;
3152                 entity->base.source_position = token.source_position;
3153                 entity->base.symbol          = symbol;
3154                 entity->base.parent_scope    = current_scope;
3155         }
3156
3157         type_t *const type = allocate_type_zero(TYPE_ENUM);
3158         type->enumt.enume  = &entity->enume;
3159         type->enumt.akind  = ATOMIC_TYPE_INT;
3160
3161         if (token.type == '{') {
3162                 if (symbol != NULL) {
3163                         environment_push(entity);
3164                 }
3165                 append_entity(current_scope, entity);
3166                 entity->enume.complete = true;
3167
3168                 parse_enum_entries(type);
3169                 parse_attributes(&attributes);
3170
3171                 /* ISO/IEC 14882:1998(E) §7.1.3:5 */
3172                 if (symbol == NULL) {
3173                         assert(anonymous_entity == NULL);
3174                         anonymous_entity = entity;
3175                 }
3176         } else if (!entity->enume.complete && !(c_mode & _GNUC)) {
3177                 errorf(HERE, "'enum %Y' used before definition (incomplete enums are a GNU extension)",
3178                        symbol);
3179         }
3180
3181         return type;
3182 }
3183
3184 /**
3185  * if a symbol is a typedef to another type, return true
3186  */
3187 static bool is_typedef_symbol(symbol_t *symbol)
3188 {
3189         const entity_t *const entity = get_entity(symbol, NAMESPACE_NORMAL);
3190         return entity != NULL && entity->kind == ENTITY_TYPEDEF;
3191 }
3192
3193 static type_t *parse_typeof(void)
3194 {
3195         eat(T___typeof__);
3196
3197         type_t *type;
3198
3199         expect('(', end_error);
3200         add_anchor_token(')');
3201
3202         expression_t *expression  = NULL;
3203
3204         bool old_type_prop     = in_type_prop;
3205         bool old_gcc_extension = in_gcc_extension;
3206         in_type_prop           = true;
3207
3208         while (token.type == T___extension__) {
3209                 /* This can be a prefix to a typename or an expression. */
3210                 next_token();
3211                 in_gcc_extension = true;
3212         }
3213         switch (token.type) {
3214         case T_IDENTIFIER:
3215                 if (is_typedef_symbol(token.v.symbol)) {
3216                         type = parse_typename();
3217                 } else {
3218                         expression = parse_expression();
3219                         type       = revert_automatic_type_conversion(expression);
3220                 }
3221                 break;
3222
3223         TYPENAME_START
3224                 type = parse_typename();
3225                 break;
3226
3227         default:
3228                 expression = parse_expression();
3229                 type       = expression->base.type;
3230                 break;
3231         }
3232         in_type_prop     = old_type_prop;
3233         in_gcc_extension = old_gcc_extension;
3234
3235         rem_anchor_token(')');
3236         expect(')', end_error);
3237
3238         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF);
3239         typeof_type->typeoft.expression  = expression;
3240         typeof_type->typeoft.typeof_type = type;
3241
3242         return typeof_type;
3243 end_error:
3244         return NULL;
3245 }
3246
3247 typedef enum specifiers_t {
3248         SPECIFIER_SIGNED    = 1 << 0,
3249         SPECIFIER_UNSIGNED  = 1 << 1,
3250         SPECIFIER_LONG      = 1 << 2,
3251         SPECIFIER_INT       = 1 << 3,
3252         SPECIFIER_DOUBLE    = 1 << 4,
3253         SPECIFIER_CHAR      = 1 << 5,
3254         SPECIFIER_WCHAR_T   = 1 << 6,
3255         SPECIFIER_SHORT     = 1 << 7,
3256         SPECIFIER_LONG_LONG = 1 << 8,
3257         SPECIFIER_FLOAT     = 1 << 9,
3258         SPECIFIER_BOOL      = 1 << 10,
3259         SPECIFIER_VOID      = 1 << 11,
3260         SPECIFIER_INT8      = 1 << 12,
3261         SPECIFIER_INT16     = 1 << 13,
3262         SPECIFIER_INT32     = 1 << 14,
3263         SPECIFIER_INT64     = 1 << 15,
3264         SPECIFIER_INT128    = 1 << 16,
3265         SPECIFIER_COMPLEX   = 1 << 17,
3266         SPECIFIER_IMAGINARY = 1 << 18,
3267 } specifiers_t;
3268
3269 static type_t *create_builtin_type(symbol_t *const symbol,
3270                                    type_t *const real_type)
3271 {
3272         type_t *type            = allocate_type_zero(TYPE_BUILTIN);
3273         type->builtin.symbol    = symbol;
3274         type->builtin.real_type = real_type;
3275         return identify_new_type(type);
3276 }
3277
3278 static type_t *get_typedef_type(symbol_t *symbol)
3279 {
3280         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
3281         if (entity == NULL || entity->kind != ENTITY_TYPEDEF)
3282                 return NULL;
3283
3284         type_t *type            = allocate_type_zero(TYPE_TYPEDEF);
3285         type->typedeft.typedefe = &entity->typedefe;
3286
3287         return type;
3288 }
3289
3290 /**
3291  * check for the allowed MS alignment values.
3292  */
3293 static bool check_alignment_value(long long intvalue)
3294 {
3295         if (intvalue < 1 || intvalue > 8192) {
3296                 errorf(HERE, "illegal alignment value");
3297                 return false;
3298         }
3299         unsigned v = (unsigned)intvalue;
3300         for (unsigned i = 1; i <= 8192; i += i) {
3301                 if (i == v)
3302                         return true;
3303         }
3304         errorf(HERE, "alignment must be power of two");
3305         return false;
3306 }
3307
3308 #define DET_MOD(name, tag) do { \
3309         if (*modifiers & tag && warning.other) warningf(HERE, #name " used more than once"); \
3310         *modifiers |= tag; \
3311 } while (0)
3312
3313 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
3314 {
3315         decl_modifiers_t *modifiers = &specifiers->modifiers;
3316
3317         while (true) {
3318                 if (token.type == T_restrict) {
3319                         next_token();
3320                         DET_MOD(restrict, DM_RESTRICT);
3321                         goto end_loop;
3322                 } else if (token.type != T_IDENTIFIER)
3323                         break;
3324                 symbol_t *symbol = token.v.symbol;
3325                 if (symbol == sym_align) {
3326                         next_token();
3327                         expect('(', end_error);
3328                         if (token.type != T_INTEGER)
3329                                 goto end_error;
3330                         if (check_alignment_value(token.v.intvalue)) {
3331                                 if (specifiers->alignment != 0 && warning.other)
3332                                         warningf(HERE, "align used more than once");
3333                                 specifiers->alignment = (unsigned char)token.v.intvalue;
3334                         }
3335                         next_token();
3336                         expect(')', end_error);
3337                 } else if (symbol == sym_allocate) {
3338                         next_token();
3339                         expect('(', end_error);
3340                         if (token.type != T_IDENTIFIER)
3341                                 goto end_error;
3342                         (void)token.v.symbol;
3343                         expect(')', end_error);
3344                 } else if (symbol == sym_dllimport) {
3345                         next_token();
3346                         DET_MOD(dllimport, DM_DLLIMPORT);
3347                 } else if (symbol == sym_dllexport) {
3348                         next_token();
3349                         DET_MOD(dllexport, DM_DLLEXPORT);
3350                 } else if (symbol == sym_thread) {
3351                         next_token();
3352                         DET_MOD(thread, DM_THREAD);
3353                 } else if (symbol == sym_naked) {
3354                         next_token();
3355                         DET_MOD(naked, DM_NAKED);
3356                 } else if (symbol == sym_noinline) {
3357                         next_token();
3358                         DET_MOD(noinline, DM_NOINLINE);
3359                 } else if (symbol == sym_returns_twice) {
3360                         next_token();
3361                         DET_MOD(returns_twice, DM_RETURNS_TWICE);
3362                 } else if (symbol == sym_noreturn) {
3363                         next_token();
3364                         DET_MOD(noreturn, DM_NORETURN);
3365                 } else if (symbol == sym_nothrow) {
3366                         next_token();
3367                         DET_MOD(nothrow, DM_NOTHROW);
3368                 } else if (symbol == sym_novtable) {
3369                         next_token();
3370                         DET_MOD(novtable, DM_NOVTABLE);
3371                 } else if (symbol == sym_property) {
3372                         next_token();
3373                         expect('(', end_error);
3374                         for (;;) {
3375                                 bool is_get = false;
3376                                 if (token.type != T_IDENTIFIER)
3377                                         goto end_error;
3378                                 if (token.v.symbol == sym_get) {
3379                                         is_get = true;
3380                                 } else if (token.v.symbol == sym_put) {
3381                                 } else {
3382                                         errorf(HERE, "Bad property name '%Y'", token.v.symbol);
3383                                         goto end_error;
3384                                 }
3385                                 next_token();
3386                                 expect('=', end_error);
3387                                 if (token.type != T_IDENTIFIER)
3388                                         goto end_error;
3389                                 if (is_get) {
3390                                         if (specifiers->get_property_sym != NULL) {
3391                                                 errorf(HERE, "get property name already specified");
3392                                         } else {
3393                                                 specifiers->get_property_sym = token.v.symbol;
3394                                         }
3395                                 } else {
3396                                         if (specifiers->put_property_sym != NULL) {
3397                                                 errorf(HERE, "put property name already specified");
3398                                         } else {
3399                                                 specifiers->put_property_sym = token.v.symbol;
3400                                         }
3401                                 }
3402                                 next_token();
3403                                 if (token.type == ',') {
3404                                         next_token();
3405                                         continue;
3406                                 }
3407                                 break;
3408                         }
3409                         expect(')', end_error);
3410                 } else if (symbol == sym_selectany) {
3411                         next_token();
3412                         DET_MOD(selectany, DM_SELECTANY);
3413                 } else if (symbol == sym_uuid) {
3414                         next_token();
3415                         expect('(', end_error);
3416                         if (token.type != T_STRING_LITERAL)
3417                                 goto end_error;
3418                         next_token();
3419                         expect(')', end_error);
3420                 } else if (symbol == sym_deprecated) {
3421                         next_token();
3422                         if (specifiers->deprecated != 0 && warning.other)
3423                                 warningf(HERE, "deprecated used more than once");
3424                         specifiers->deprecated = true;
3425                         if (token.type == '(') {
3426                                 next_token();
3427                                 if (token.type == T_STRING_LITERAL) {
3428                                         specifiers->deprecated_string = token.v.string.begin;
3429                                         next_token();
3430                                 } else {
3431                                         errorf(HERE, "string literal expected");
3432                                 }
3433                                 expect(')', end_error);
3434                         }
3435                 } else if (symbol == sym_noalias) {
3436                         next_token();
3437                         DET_MOD(noalias, DM_NOALIAS);
3438                 } else {
3439                         if (warning.other)
3440                                 warningf(HERE, "Unknown modifier '%Y' ignored", token.v.symbol);
3441                         next_token();
3442                         if (token.type == '(')
3443                                 skip_until(')');
3444                 }
3445 end_loop:
3446                 if (token.type == ',')
3447                         next_token();
3448         }
3449 end_error:
3450         return;
3451 }
3452
3453 static entity_t *create_error_entity(symbol_t *symbol, entity_kind_tag_t kind)
3454 {
3455         entity_t *entity             = allocate_entity_zero(kind);
3456         entity->base.source_position = *HERE;
3457         entity->base.symbol          = symbol;
3458         if (is_declaration(entity)) {
3459                 entity->declaration.type     = type_error_type;
3460                 entity->declaration.implicit = true;
3461         } else if (kind == ENTITY_TYPEDEF) {
3462                 entity->typedefe.type    = type_error_type;
3463                 entity->typedefe.builtin = true;
3464         }
3465         if (kind != ENTITY_COMPOUND_MEMBER)
3466                 record_entity(entity, false);
3467         return entity;
3468 }
3469
3470 static variable_t *parse_microsoft_based(void)
3471 {
3472         if (token.type != T_IDENTIFIER) {
3473                 parse_error_expected("while parsing __based", T_IDENTIFIER, NULL);
3474                 return NULL;
3475         }
3476         symbol_t *symbol = token.v.symbol;
3477         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
3478
3479         variable_t *variable;
3480         if (entity == NULL || entity->base.kind != ENTITY_VARIABLE) {
3481                 errorf(HERE, "'%Y' is not a variable name.", symbol);
3482                 variable = &create_error_entity(symbol, ENTITY_VARIABLE)->variable;
3483         } else {
3484                 variable = &entity->variable;
3485
3486                 type_t *const type = variable->base.type;
3487                 if (is_type_valid(type)) {
3488                         if (! is_type_pointer(skip_typeref(type))) {
3489                                 errorf(HERE, "variable in __based modifier must have pointer type instead of '%T'", type);
3490                         }
3491                         if (variable->base.base.parent_scope != file_scope) {
3492                                 errorf(HERE, "a nonstatic local variable may not be used in a __based specification");
3493                         }
3494                 }
3495         }
3496         next_token();
3497         return variable;
3498 }
3499
3500 /**
3501  * Finish the construction of a struct type by calculating
3502  * its size, offsets, alignment.
3503  */
3504 static void finish_struct_type(compound_type_t *type)
3505 {
3506         assert(type->compound != NULL);
3507
3508         compound_t *compound = type->compound;
3509         if (!compound->complete)
3510                 return;
3511
3512         il_size_t      size           = 0;
3513         il_size_t      offset;
3514         il_alignment_t alignment      = 1;
3515         bool           need_pad       = false;
3516
3517         entity_t *entry = compound->members.entities;
3518         for (; entry != NULL; entry = entry->base.next) {
3519                 if (entry->kind != ENTITY_COMPOUND_MEMBER)
3520                         continue;
3521
3522                 type_t *m_type = skip_typeref(entry->declaration.type);
3523                 if (! is_type_valid(m_type)) {
3524                         /* simply ignore errors here */
3525                         continue;
3526                 }
3527                 il_alignment_t m_alignment = m_type->base.alignment;
3528                 if (m_alignment > alignment)
3529                         alignment = m_alignment;
3530
3531                 offset = (size + m_alignment - 1) & -m_alignment;
3532
3533                 if (offset > size)
3534                         need_pad = true;
3535                 entry->compound_member.offset = offset;
3536                 size = offset + m_type->base.size;
3537         }
3538         if (type->base.alignment != 0) {
3539                 alignment = type->base.alignment;
3540         }
3541
3542         offset = (size + alignment - 1) & -alignment;
3543         if (offset > size)
3544                 need_pad = true;
3545
3546         if (need_pad) {
3547                 if (warning.padded) {
3548                         warningf(&compound->base.source_position, "'%T' needs padding", type);
3549                 }
3550         } else {
3551                 if (compound->modifiers & DM_PACKED && warning.packed) {
3552                         warningf(&compound->base.source_position,
3553                                         "superfluous packed attribute on '%T'", type);
3554                 }
3555         }
3556
3557         type->base.size      = offset;
3558         type->base.alignment = alignment;
3559 }
3560
3561 /**
3562  * Finish the construction of an union type by calculating
3563  * its size and alignment.
3564  */
3565 static void finish_union_type(compound_type_t *type)
3566 {
3567         assert(type->compound != NULL);
3568
3569         compound_t *compound = type->compound;
3570         if (! compound->complete)
3571                 return;
3572
3573         il_size_t      size      = 0;
3574         il_alignment_t alignment = 1;
3575
3576         entity_t *entry = compound->members.entities;
3577         for (; entry != NULL; entry = entry->base.next) {
3578                 if (entry->kind != ENTITY_COMPOUND_MEMBER)
3579                         continue;
3580
3581                 type_t *m_type = skip_typeref(entry->declaration.type);
3582                 if (! is_type_valid(m_type))
3583                         continue;
3584
3585                 entry->compound_member.offset = 0;
3586                 if (m_type->base.size > size)
3587                         size = m_type->base.size;
3588                 if (m_type->base.alignment > alignment)
3589                         alignment = m_type->base.alignment;
3590         }
3591         if (type->base.alignment != 0) {
3592                 alignment = type->base.alignment;
3593         }
3594         size = (size + alignment - 1) & -alignment;
3595         type->base.size      = size;
3596         type->base.alignment = alignment;
3597 }
3598
3599 static type_t *handle_attribute_mode(const gnu_attribute_t *attribute,
3600                                      type_t *orig_type)
3601 {
3602         type_t *type = skip_typeref(orig_type);
3603
3604         /* at least: byte, word, pointer, list of machine modes
3605          * __XXX___ is interpreted as XXX */
3606
3607         /* This isn't really correct, the backend should provide a list of machine
3608          * specific modes (according to gcc philosophy that is...) */
3609         const char         *symbol_str = attribute->u.symbol->string;
3610         bool                sign       = is_type_signed(type);
3611         atomic_type_kind_t  akind;
3612         if (strcmp_underscore("QI",   symbol_str) == 0 ||
3613             strcmp_underscore("byte", symbol_str) == 0) {
3614                 akind = sign ? ATOMIC_TYPE_CHAR : ATOMIC_TYPE_UCHAR;
3615         } else if (strcmp_underscore("HI", symbol_str) == 0) {
3616                 akind = sign ? ATOMIC_TYPE_SHORT : ATOMIC_TYPE_USHORT;
3617         } else if (strcmp_underscore("SI",      symbol_str) == 0
3618                 || strcmp_underscore("word",    symbol_str) == 0
3619                 || strcmp_underscore("pointer", symbol_str) == 0) {
3620                 akind = sign ? ATOMIC_TYPE_INT : ATOMIC_TYPE_UINT;
3621         } else if (strcmp_underscore("DI", symbol_str) == 0) {
3622                 akind = sign ? ATOMIC_TYPE_LONGLONG : ATOMIC_TYPE_ULONGLONG;
3623         } else {
3624                 if (warning.other)
3625                         warningf(HERE, "ignoring unknown mode '%s'", symbol_str);
3626                 return orig_type;
3627         }
3628
3629         if (type->kind == TYPE_ATOMIC) {
3630                 type_t *copy       = duplicate_type(type);
3631                 copy->atomic.akind = akind;
3632                 return identify_new_type(copy);
3633         } else if (type->kind == TYPE_ENUM) {
3634                 type_t *copy      = duplicate_type(type);
3635                 copy->enumt.akind = akind;
3636                 return identify_new_type(copy);
3637         } else if (is_type_pointer(type)) {
3638                 warningf(HERE, "__attribute__((mode)) on pointers not implemented yet (ignored)");
3639                 return type;
3640         }
3641
3642         errorf(HERE, "__attribute__((mode)) only allowed on integer, enum or pointer type");
3643         return orig_type;
3644 }
3645
3646 static type_t *handle_type_attributes(const gnu_attribute_t *attributes,
3647                                       type_t *type)
3648 {
3649         const gnu_attribute_t *attribute = attributes;
3650         for ( ; attribute != NULL; attribute = attribute->next) {
3651                 if (attribute->invalid)
3652                         continue;
3653
3654                 if (attribute->kind == GNU_AK_MODE) {
3655                         type = handle_attribute_mode(attribute, type);
3656                 } else if (attribute->kind == GNU_AK_ALIGNED) {
3657                         int alignment = 32; /* TODO: fill in maximum useful alignment for
3658                                                target machine */
3659                         if (attribute->has_arguments)
3660                                 alignment = attribute->u.argument;
3661
3662                         type_t *copy         = duplicate_type(type);
3663                         copy->base.alignment = attribute->u.argument;
3664                         type                 = identify_new_type(copy);
3665                 }
3666         }
3667
3668         return type;
3669 }
3670
3671 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
3672 {
3673         type_t            *type              = NULL;
3674         type_qualifiers_t  qualifiers        = TYPE_QUALIFIER_NONE;
3675         type_modifiers_t   modifiers         = TYPE_MODIFIER_NONE;
3676         unsigned           type_specifiers   = 0;
3677         bool               newtype           = false;
3678         bool               saw_error         = false;
3679         bool               old_gcc_extension = in_gcc_extension;
3680
3681         specifiers->source_position = token.source_position;
3682
3683         while (true) {
3684                 specifiers->modifiers
3685                         |= parse_attributes(&specifiers->gnu_attributes);
3686
3687                 switch (token.type) {
3688                 /* storage class */
3689 #define MATCH_STORAGE_CLASS(token, class)                                  \
3690                 case token:                                                        \
3691                         if (specifiers->storage_class != STORAGE_CLASS_NONE) {         \
3692                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3693                         }                                                              \
3694                         specifiers->storage_class = class;                             \
3695                         if (specifiers->thread_local)                                  \
3696                                 goto check_thread_storage_class;                           \
3697                         next_token();                                                  \
3698                         break;
3699
3700                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3701                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3702                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3703                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3704                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3705
3706                 case T__declspec:
3707                         next_token();
3708                         expect('(', end_error);
3709                         add_anchor_token(')');
3710                         parse_microsoft_extended_decl_modifier(specifiers);
3711                         rem_anchor_token(')');
3712                         expect(')', end_error);
3713                         break;
3714
3715                 case T___thread:
3716                         if (specifiers->thread_local) {
3717                                 errorf(HERE, "duplicate '__thread'");
3718                         } else {
3719                                 specifiers->thread_local = true;
3720 check_thread_storage_class:
3721                                 switch (specifiers->storage_class) {
3722                                         case STORAGE_CLASS_EXTERN:
3723                                         case STORAGE_CLASS_NONE:
3724                                         case STORAGE_CLASS_STATIC:
3725                                                 break;
3726
3727                                                 char const* wrong;
3728                                         case STORAGE_CLASS_AUTO:     wrong = "auto";     goto wrong_thread_stoarge_class;
3729                                         case STORAGE_CLASS_REGISTER: wrong = "register"; goto wrong_thread_stoarge_class;
3730                                         case STORAGE_CLASS_TYPEDEF:  wrong = "typedef";  goto wrong_thread_stoarge_class;
3731 wrong_thread_stoarge_class:
3732                                                 errorf(HERE, "'__thread' used with '%s'", wrong);
3733                                                 break;
3734                                 }
3735                         }
3736                         next_token();
3737                         break;
3738
3739                 /* type qualifiers */
3740 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3741                 case token:                                                     \
3742                         qualifiers |= qualifier;                                    \
3743                         next_token();                                               \
3744                         break
3745
3746                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3747                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3748                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3749                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3750                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3751                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3752                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3753                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3754
3755                 case T___extension__:
3756                         next_token();
3757                         in_gcc_extension = true;
3758                         break;
3759
3760                 /* type specifiers */
3761 #define MATCH_SPECIFIER(token, specifier, name)                         \
3762                 case token:                                                     \
3763                         if (type_specifiers & specifier) {                           \
3764                                 errorf(HERE, "multiple " name " type specifiers given"); \
3765                         } else {                                                    \
3766                                 type_specifiers |= specifier;                           \
3767                         }                                                           \
3768                         next_token();                                               \
3769                         break
3770
3771                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3772                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3773                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3774                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3775                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3776                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3777                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3778                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3779                 MATCH_SPECIFIER(T_bool,       SPECIFIER_BOOL,      "bool");
3780                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3781                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3782                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3783                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3784                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3785                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3786                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3787                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3788                 MATCH_SPECIFIER(T_wchar_t,    SPECIFIER_WCHAR_T,   "wchar_t");
3789
3790                 case T__forceinline:
3791                         /* only in microsoft mode */
3792                         specifiers->modifiers |= DM_FORCEINLINE;
3793                         /* FALLTHROUGH */
3794
3795                 case T_inline:
3796                         next_token();
3797                         specifiers->is_inline = true;
3798                         break;
3799
3800                 case T_long:
3801                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3802                                 errorf(HERE, "multiple type specifiers given");
3803                         } else if (type_specifiers & SPECIFIER_LONG) {
3804                                 type_specifiers |= SPECIFIER_LONG_LONG;
3805                         } else {
3806                                 type_specifiers |= SPECIFIER_LONG;
3807                         }
3808                         next_token();
3809                         break;
3810
3811                 case T_struct: {
3812                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT);
3813
3814                         type->compound.compound = parse_compound_type_specifier(true);
3815                         finish_struct_type(&type->compound);
3816                         break;
3817                 }
3818                 case T_union: {
3819                         type = allocate_type_zero(TYPE_COMPOUND_UNION);
3820                         type->compound.compound = parse_compound_type_specifier(false);
3821                         if (type->compound.compound->modifiers & DM_TRANSPARENT_UNION)
3822                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3823                         finish_union_type(&type->compound);
3824                         break;
3825                 }
3826                 case T_enum:
3827                         type = parse_enum_specifier();
3828                         break;
3829                 case T___typeof__:
3830                         type = parse_typeof();
3831                         break;
3832                 case T___builtin_va_list:
3833                         type = duplicate_type(type_valist);
3834                         next_token();
3835                         break;
3836
3837                 case T_IDENTIFIER: {
3838                         /* only parse identifier if we haven't found a type yet */
3839                         if (type != NULL || type_specifiers != 0) {
3840                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
3841                                  * declaration, so it doesn't generate errors about expecting '(' or
3842                                  * '{' later on. */
3843                                 switch (look_ahead(1)->type) {
3844                                         STORAGE_CLASSES
3845                                         TYPE_SPECIFIERS
3846                                         case T_const:
3847                                         case T_restrict:
3848                                         case T_volatile:
3849                                         case T_inline:
3850                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
3851                                         case T_IDENTIFIER:
3852                                         case '&':
3853                                         case '*':
3854                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
3855                                                 next_token();
3856                                                 continue;
3857
3858                                         default:
3859                                                 goto finish_specifiers;
3860                                 }
3861                         }
3862
3863                         type_t *const typedef_type = get_typedef_type(token.v.symbol);
3864                         if (typedef_type == NULL) {
3865                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3866                                  * declaration, so it doesn't generate 'implicit int' followed by more
3867                                  * errors later on. */
3868                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3869                                 switch (la1_type) {
3870                                         DECLARATION_START
3871                                         case T_IDENTIFIER:
3872                                         case '&':
3873                                         case '*': {
3874                                                 errorf(HERE, "%K does not name a type", &token);
3875
3876                                                 entity_t *entity =
3877                                                         create_error_entity(token.v.symbol, ENTITY_TYPEDEF);
3878
3879                                                 type = allocate_type_zero(TYPE_TYPEDEF);
3880                                                 type->typedeft.typedefe = &entity->typedefe;
3881
3882                                                 next_token();
3883                                                 saw_error = true;
3884                                                 if (la1_type == '&' || la1_type == '*')
3885                                                         goto finish_specifiers;
3886                                                 continue;
3887                                         }
3888
3889                                         default:
3890                                                 goto finish_specifiers;
3891                                 }
3892                         }
3893
3894                         next_token();
3895                         type = typedef_type;
3896                         break;
3897                 }
3898
3899                 /* function specifier */
3900                 default:
3901                         goto finish_specifiers;
3902                 }
3903         }
3904
3905 finish_specifiers:
3906         specifiers->modifiers
3907                 |= parse_attributes(&specifiers->gnu_attributes);
3908
3909         in_gcc_extension = old_gcc_extension;
3910
3911         if (type == NULL || (saw_error && type_specifiers != 0)) {
3912                 atomic_type_kind_t atomic_type;
3913
3914                 /* match valid basic types */
3915                 switch (type_specifiers) {
3916                 case SPECIFIER_VOID:
3917                         atomic_type = ATOMIC_TYPE_VOID;
3918                         break;
3919                 case SPECIFIER_WCHAR_T:
3920                         atomic_type = ATOMIC_TYPE_WCHAR_T;
3921                         break;
3922                 case SPECIFIER_CHAR:
3923                         atomic_type = ATOMIC_TYPE_CHAR;
3924                         break;
3925                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3926                         atomic_type = ATOMIC_TYPE_SCHAR;
3927                         break;
3928                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3929                         atomic_type = ATOMIC_TYPE_UCHAR;
3930                         break;
3931                 case SPECIFIER_SHORT:
3932                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3933                 case SPECIFIER_SHORT | SPECIFIER_INT:
3934                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3935                         atomic_type = ATOMIC_TYPE_SHORT;
3936                         break;
3937                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3938                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3939                         atomic_type = ATOMIC_TYPE_USHORT;
3940                         break;
3941                 case SPECIFIER_INT:
3942                 case SPECIFIER_SIGNED:
3943                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3944                         atomic_type = ATOMIC_TYPE_INT;
3945                         break;
3946                 case SPECIFIER_UNSIGNED:
3947                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3948                         atomic_type = ATOMIC_TYPE_UINT;
3949                         break;
3950                 case SPECIFIER_LONG:
3951                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3952                 case SPECIFIER_LONG | SPECIFIER_INT:
3953                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3954                         atomic_type = ATOMIC_TYPE_LONG;
3955                         break;
3956                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3957                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3958                         atomic_type = ATOMIC_TYPE_ULONG;
3959                         break;
3960
3961                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3962                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3963                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3964                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3965                         | SPECIFIER_INT:
3966                         atomic_type = ATOMIC_TYPE_LONGLONG;
3967                         goto warn_about_long_long;
3968
3969                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3970                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3971                         | SPECIFIER_INT:
3972                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3973 warn_about_long_long:
3974                         if (warning.long_long) {
3975                                 warningf(&specifiers->source_position,
3976                                          "ISO C90 does not support 'long long'");
3977                         }
3978                         break;
3979
3980                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3981                         atomic_type = unsigned_int8_type_kind;
3982                         break;
3983
3984                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3985                         atomic_type = unsigned_int16_type_kind;
3986                         break;
3987
3988                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3989                         atomic_type = unsigned_int32_type_kind;
3990                         break;
3991
3992                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3993                         atomic_type = unsigned_int64_type_kind;
3994                         break;
3995
3996                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3997                         atomic_type = unsigned_int128_type_kind;
3998                         break;
3999
4000                 case SPECIFIER_INT8:
4001                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
4002                         atomic_type = int8_type_kind;
4003                         break;
4004
4005                 case SPECIFIER_INT16:
4006                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
4007                         atomic_type = int16_type_kind;
4008                         break;
4009
4010                 case SPECIFIER_INT32:
4011                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
4012                         atomic_type = int32_type_kind;
4013                         break;
4014
4015                 case SPECIFIER_INT64:
4016                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
4017                         atomic_type = int64_type_kind;
4018                         break;
4019
4020                 case SPECIFIER_INT128:
4021                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
4022                         atomic_type = int128_type_kind;
4023                         break;
4024
4025                 case SPECIFIER_FLOAT:
4026                         atomic_type = ATOMIC_TYPE_FLOAT;
4027                         break;
4028                 case SPECIFIER_DOUBLE:
4029                         atomic_type = ATOMIC_TYPE_DOUBLE;
4030                         break;
4031                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
4032                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
4033                         break;
4034                 case SPECIFIER_BOOL:
4035                         atomic_type = ATOMIC_TYPE_BOOL;
4036                         break;
4037                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
4038                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
4039                         atomic_type = ATOMIC_TYPE_FLOAT;
4040                         break;
4041                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
4042                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
4043                         atomic_type = ATOMIC_TYPE_DOUBLE;
4044                         break;
4045                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
4046                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
4047                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
4048                         break;
4049                 default:
4050                         /* invalid specifier combination, give an error message */
4051                         if (type_specifiers == 0) {
4052                                 if (saw_error)
4053                                         goto end_error;
4054
4055                                 /* ISO/IEC 14882:1998(E) §C.1.5:4 */
4056                                 if (!(c_mode & _CXX) && !strict_mode) {
4057                                         if (warning.implicit_int) {
4058                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
4059                                         }
4060                                         atomic_type = ATOMIC_TYPE_INT;
4061                                         break;
4062                                 } else {
4063                                         errorf(HERE, "no type specifiers given in declaration");
4064                                 }
4065                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
4066                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
4067                                 errorf(HERE, "signed and unsigned specifiers given");
4068                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
4069                                 errorf(HERE, "only integer types can be signed or unsigned");
4070                         } else {
4071                                 errorf(HERE, "multiple datatypes in declaration");
4072                         }
4073                         goto end_error;
4074                 }
4075
4076                 if (type_specifiers & SPECIFIER_COMPLEX) {
4077                         type                = allocate_type_zero(TYPE_COMPLEX);
4078                         type->complex.akind = atomic_type;
4079                 } else if (type_specifiers & SPECIFIER_IMAGINARY) {
4080                         type                  = allocate_type_zero(TYPE_IMAGINARY);
4081                         type->imaginary.akind = atomic_type;
4082                 } else {
4083                         type                 = allocate_type_zero(TYPE_ATOMIC);
4084                         type->atomic.akind   = atomic_type;
4085                 }
4086                 type->base.alignment = get_atomic_type_alignment(atomic_type);
4087                 unsigned const size  = get_atomic_type_size(atomic_type);
4088                 type->base.size      =
4089                         type_specifiers & SPECIFIER_COMPLEX ? size * 2 : size;
4090                 newtype = true;
4091         } else if (type_specifiers != 0) {
4092                 errorf(HERE, "multiple datatypes in declaration");
4093         }
4094
4095         /* FIXME: check type qualifiers here */
4096
4097         if (specifiers->modifiers & DM_TRANSPARENT_UNION)
4098                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
4099         type->base.qualifiers = qualifiers;
4100         type->base.modifiers  = modifiers;
4101
4102         if (newtype) {
4103                 type = identify_new_type(type);
4104         } else {
4105                 type = typehash_insert(type);
4106         }
4107
4108         type = handle_type_attributes(specifiers->gnu_attributes, type);
4109         specifiers->type = type;
4110         return;
4111
4112 end_error:
4113         specifiers->type = type_error_type;
4114         return;
4115 }
4116
4117 static type_qualifiers_t parse_type_qualifiers(void)
4118 {
4119         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
4120
4121         while (true) {
4122                 switch (token.type) {
4123                 /* type qualifiers */
4124                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
4125                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
4126                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
4127                 /* microsoft extended type modifiers */
4128                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
4129                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
4130                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
4131                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
4132                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
4133
4134                 default:
4135                         return qualifiers;
4136                 }
4137         }
4138 }
4139
4140 /**
4141  * Parses an K&R identifier list
4142  */
4143 static void parse_identifier_list(scope_t *scope)
4144 {
4145         do {
4146                 entity_t *entity = allocate_entity_zero(ENTITY_PARAMETER);
4147                 entity->base.source_position = token.source_position;
4148                 entity->base.namespc         = NAMESPACE_NORMAL;
4149                 entity->base.symbol          = token.v.symbol;
4150                 /* a K&R parameter has no type, yet */
4151                 next_token();
4152
4153                 if (scope != NULL)
4154                         append_entity(scope, entity);
4155
4156                 if (token.type != ',') {
4157                         break;
4158                 }
4159                 next_token();
4160         } while (token.type == T_IDENTIFIER);
4161 }
4162
4163 static entity_t *parse_parameter(void)
4164 {
4165         declaration_specifiers_t specifiers;
4166         memset(&specifiers, 0, sizeof(specifiers));
4167
4168         parse_declaration_specifiers(&specifiers);
4169
4170         entity_t *entity = parse_declarator(&specifiers,
4171                         DECL_MAY_BE_ABSTRACT | DECL_IS_PARAMETER);
4172         anonymous_entity = NULL;
4173         return entity;
4174 }
4175
4176 static void semantic_parameter_incomplete(const entity_t *entity)
4177 {
4178         assert(entity->kind == ENTITY_PARAMETER);
4179
4180         /* §6.7.5.3:4  After adjustment, the parameters in a parameter type
4181          *             list in a function declarator that is part of a
4182          *             definition of that function shall not have
4183          *             incomplete type. */
4184         type_t *type = skip_typeref(entity->declaration.type);
4185         if (is_type_incomplete(type)) {
4186                 errorf(&entity->base.source_position,
4187                                 "parameter '%#T' has incomplete type",
4188                                 entity->declaration.type, entity->base.symbol);
4189         }
4190 }
4191
4192 static bool has_parameters(void)
4193 {
4194         /* func(void) is not a parameter */
4195         if (token.type == T_IDENTIFIER) {
4196                 entity_t const *const entity = get_entity(token.v.symbol, NAMESPACE_NORMAL);
4197                 if (entity->kind != ENTITY_TYPEDEF)
4198                         return true;
4199                 if (skip_typeref(entity->typedefe.type) != type_void)
4200                         return true;
4201         } else if (token.type != T_void) {
4202                 return true;
4203         }
4204         if (look_ahead(1)->type != ')')
4205                 return true;
4206         next_token();
4207         return false;
4208 }
4209
4210 /**
4211  * Parses function type parameters (and optionally creates variable_t entities
4212  * for them in a scope)
4213  */
4214 static void parse_parameters(function_type_t *type, scope_t *scope)
4215 {
4216         eat('(');
4217         add_anchor_token(')');
4218         int saved_comma_state = save_and_reset_anchor_state(',');
4219
4220         if (token.type == T_IDENTIFIER &&
4221             !is_typedef_symbol(token.v.symbol)) {
4222                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
4223                 if (la1_type == ',' || la1_type == ')') {
4224                         type->kr_style_parameters    = true;
4225                         type->unspecified_parameters = true;
4226                         parse_identifier_list(scope);
4227                         goto parameters_finished;
4228                 }
4229         }
4230
4231         if (token.type == ')') {
4232                 /* ISO/IEC 14882:1998(E) §C.1.6:1 */
4233                 if (!(c_mode & _CXX))
4234                         type->unspecified_parameters = true;
4235                 goto parameters_finished;
4236         }
4237
4238         if (has_parameters()) {
4239                 function_parameter_t **anchor = &type->parameters;
4240                 for (;;) {
4241                         switch (token.type) {
4242                         case T_DOTDOTDOT:
4243                                 next_token();
4244                                 type->variadic = true;
4245                                 goto parameters_finished;
4246
4247                         case T_IDENTIFIER:
4248                         case T___extension__:
4249                         DECLARATION_START
4250                         {
4251                                 entity_t *entity = parse_parameter();
4252                                 if (entity->kind == ENTITY_TYPEDEF) {
4253                                         errorf(&entity->base.source_position,
4254                                                         "typedef not allowed as function parameter");
4255                                         break;
4256                                 }
4257                                 assert(is_declaration(entity));
4258
4259                                 semantic_parameter_incomplete(entity);
4260
4261                                 function_parameter_t *const parameter =
4262                                         allocate_parameter(entity->declaration.type);
4263
4264                                 if (scope != NULL) {
4265                                         append_entity(scope, entity);
4266                                 }
4267
4268                                 *anchor = parameter;
4269                                 anchor  = &parameter->next;
4270                                 break;
4271                         }
4272
4273                         default:
4274                                 goto parameters_finished;
4275                         }
4276                         if (token.type != ',') {
4277                                 goto parameters_finished;
4278                         }
4279                         next_token();
4280                 }
4281         }
4282
4283
4284 parameters_finished:
4285         rem_anchor_token(')');
4286         expect(')', end_error);
4287
4288 end_error:
4289         restore_anchor_state(',', saved_comma_state);
4290 }
4291
4292 typedef enum construct_type_kind_t {
4293         CONSTRUCT_INVALID,
4294         CONSTRUCT_POINTER,
4295         CONSTRUCT_REFERENCE,
4296         CONSTRUCT_FUNCTION,
4297         CONSTRUCT_ARRAY
4298 } construct_type_kind_t;
4299
4300 typedef union construct_type_t construct_type_t;
4301
4302 typedef struct construct_type_base_t {
4303         construct_type_kind_t  kind;
4304         construct_type_t      *next;
4305 } construct_type_base_t;
4306
4307 typedef struct parsed_pointer_t {
4308         construct_type_base_t  base;
4309         type_qualifiers_t      type_qualifiers;
4310         variable_t             *base_variable;  /**< MS __based extension. */
4311 } parsed_pointer_t;
4312
4313 typedef struct parsed_reference_t {
4314         construct_type_base_t base;
4315 } parsed_reference_t;
4316
4317 typedef struct construct_function_type_t {
4318         construct_type_base_t  base;
4319         type_t                *function_type;
4320 } construct_function_type_t;
4321
4322 typedef struct parsed_array_t {
4323         construct_type_base_t  base;
4324         type_qualifiers_t      type_qualifiers;
4325         bool                   is_static;
4326         bool                   is_variable;
4327         expression_t          *size;
4328 } parsed_array_t;
4329
4330 union construct_type_t {
4331         construct_type_kind_t     kind;
4332         construct_type_base_t     base;
4333         parsed_pointer_t          pointer;
4334         parsed_reference_t        reference;
4335         construct_function_type_t function;
4336         parsed_array_t            array;
4337 };
4338
4339 static construct_type_t *parse_pointer_declarator(variable_t *base_variable)
4340 {
4341         eat('*');
4342
4343         construct_type_t *cons    = obstack_alloc(&temp_obst, sizeof(cons->pointer));
4344         parsed_pointer_t *pointer = &cons->pointer;
4345         memset(pointer, 0, sizeof(*pointer));
4346         cons->kind               = CONSTRUCT_POINTER;
4347         pointer->type_qualifiers = parse_type_qualifiers();
4348         pointer->base_variable   = base_variable;
4349
4350         return cons;
4351 }
4352
4353 static construct_type_t *parse_reference_declarator(void)
4354 {
4355         eat('&');
4356
4357         construct_type_t   *cons      = obstack_alloc(&temp_obst, sizeof(cons->reference));
4358         parsed_reference_t *reference = &cons->reference;
4359         memset(reference, 0, sizeof(*reference));
4360         cons->kind = CONSTRUCT_REFERENCE;
4361
4362         return cons;
4363 }
4364
4365 static construct_type_t *parse_array_declarator(void)
4366 {
4367         eat('[');
4368         add_anchor_token(']');
4369
4370         construct_type_t *cons  = obstack_alloc(&temp_obst, sizeof(cons->array));
4371         parsed_array_t   *array = &cons->array;
4372         memset(array, 0, sizeof(*array));
4373         cons->kind = CONSTRUCT_ARRAY;
4374
4375         if (token.type == T_static) {
4376                 array->is_static = true;
4377                 next_token();
4378         }
4379
4380         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
4381         if (type_qualifiers != 0) {
4382                 if (token.type == T_static) {
4383                         array->is_static = true;
4384                         next_token();
4385                 }
4386         }
4387         array->type_qualifiers = type_qualifiers;
4388
4389         if (token.type == '*' && look_ahead(1)->type == ']') {
4390                 array->is_variable = true;
4391                 next_token();
4392         } else if (token.type != ']') {
4393                 expression_t *const size = parse_assignment_expression();
4394                 array->size = size;
4395                 mark_vars_read(size, NULL);
4396         }
4397
4398         rem_anchor_token(']');
4399         expect(']', end_error);
4400
4401 end_error:
4402         return cons;
4403 }
4404
4405 static construct_type_t *parse_function_declarator(scope_t *scope,
4406                                                    decl_modifiers_t modifiers)
4407 {
4408         type_t          *type  = allocate_type_zero(TYPE_FUNCTION);
4409         function_type_t *ftype = &type->function;
4410
4411         ftype->linkage = current_linkage;
4412
4413         switch (modifiers & (DM_CDECL | DM_STDCALL | DM_FASTCALL | DM_THISCALL)) {
4414                 case DM_NONE:     break;
4415                 case DM_CDECL:    ftype->calling_convention = CC_CDECL;    break;
4416                 case DM_STDCALL:  ftype->calling_convention = CC_STDCALL;  break;
4417                 case DM_FASTCALL: ftype->calling_convention = CC_FASTCALL; break;
4418                 case DM_THISCALL: ftype->calling_convention = CC_THISCALL; break;
4419
4420                 default:
4421                         errorf(HERE, "multiple calling conventions in declaration");
4422                         break;
4423         }
4424
4425         parse_parameters(ftype, scope);
4426
4427         construct_type_t          *cons     = obstack_alloc(&temp_obst, sizeof(cons->function));
4428         construct_function_type_t *function = &cons->function;
4429         memset(function, 0, sizeof(*function));
4430         cons->kind              = CONSTRUCT_FUNCTION;
4431         function->function_type = type;
4432
4433         return cons;
4434 }
4435
4436 typedef struct parse_declarator_env_t {
4437         decl_modifiers_t   modifiers;
4438         symbol_t          *symbol;
4439         source_position_t  source_position;
4440         scope_t            parameters;
4441 } parse_declarator_env_t;
4442
4443 static construct_type_t *parse_inner_declarator(parse_declarator_env_t *env,
4444                 bool may_be_abstract)
4445 {
4446         /* construct a single linked list of construct_type_t's which describe
4447          * how to construct the final declarator type */
4448         construct_type_t  *first      = NULL;
4449         construct_type_t **anchor     = &first;
4450         gnu_attribute_t   *attributes = NULL;
4451
4452         decl_modifiers_t modifiers = parse_attributes(&attributes);
4453
4454         for (;;) {
4455                 construct_type_t *type;
4456                 variable_t       *based = NULL; /* MS __based extension */
4457                 switch (token.type) {
4458                         case '&':
4459                                 if (!(c_mode & _CXX))
4460                                         errorf(HERE, "references are only available for C++");
4461                                 type = parse_reference_declarator();
4462                                 break;
4463
4464                         case T__based: {
4465                                 source_position_t const pos = *HERE;
4466                                 next_token();
4467                                 expect('(', end_error);
4468                                 add_anchor_token(')');
4469                                 based = parse_microsoft_based();
4470                                 rem_anchor_token(')');
4471                                 expect(')', end_error);
4472                                 if (token.type != '*') {
4473                                         if (token.type == T__based) {
4474                                                 errorf(&pos, "__based type modifier specified more than once");
4475                                         } else if (warning.other) {
4476                                                 warningf(&pos,
4477                                                                 "__based does not precede a pointer declarator, ignored");
4478                                         }
4479                                         continue;
4480                                 }
4481                                 /* FALLTHROUGH */
4482                         }
4483
4484                         case '*':
4485                                 type = parse_pointer_declarator(based);
4486                                 break;
4487
4488                         default:
4489                                 goto ptr_operator_end;
4490                 }
4491
4492                 *anchor = type;
4493                 anchor  = &type->base.next;
4494
4495                 /* TODO: find out if this is correct */
4496                 modifiers |= parse_attributes(&attributes);
4497         }
4498 ptr_operator_end:
4499
4500         if (env != NULL) {
4501                 modifiers      |= env->modifiers;
4502                 env->modifiers  = modifiers;
4503         }
4504
4505         construct_type_t *inner_types = NULL;
4506
4507         switch (token.type) {
4508         case T_IDENTIFIER:
4509                 if (env == NULL) {
4510                         errorf(HERE, "no identifier expected in typename");
4511                 } else {
4512                         env->symbol          = token.v.symbol;
4513                         env->source_position = token.source_position;
4514                 }
4515                 next_token();
4516                 break;
4517         case '(':
4518                 /* §6.7.6:2 footnote 126:  Empty parentheses in a type name are
4519                  * interpreted as ``function with no parameter specification'', rather
4520                  * than redundant parentheses around the omitted identifier. */
4521                 if (look_ahead(1)->type != ')') {
4522                         next_token();
4523                         add_anchor_token(')');
4524                         inner_types = parse_inner_declarator(env, may_be_abstract);
4525                         if (inner_types != NULL) {
4526                                 /* All later declarators only modify the return type */
4527                                 env = NULL;
4528                         }
4529                         rem_anchor_token(')');
4530                         expect(')', end_error);
4531                 }
4532                 break;
4533         default:
4534                 if (may_be_abstract)
4535                         break;
4536                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
4537                 eat_until_anchor();
4538                 return NULL;
4539         }
4540
4541         construct_type_t **const p = anchor;
4542
4543         for (;;) {
4544                 construct_type_t *type;
4545                 switch (token.type) {
4546                 case '(': {
4547                         scope_t *scope = NULL;
4548                         if (env != NULL)
4549                                 scope = &env->parameters;
4550
4551                         type = parse_function_declarator(scope, modifiers);
4552                         break;
4553                 }
4554                 case '[':
4555                         type = parse_array_declarator();
4556                         break;
4557                 default:
4558                         goto declarator_finished;
4559                 }
4560
4561                 /* insert in the middle of the list (at p) */
4562                 type->base.next = *p;
4563                 *p              = type;
4564                 if (anchor == p)
4565                         anchor = &type->base.next;
4566         }
4567
4568 declarator_finished:
4569         /* append inner_types at the end of the list, we don't to set anchor anymore
4570          * as it's not needed anymore */
4571         *anchor = inner_types;
4572
4573         return first;
4574 end_error:
4575         return NULL;
4576 }
4577
4578 static void parse_declaration_attributes(entity_t *entity)
4579 {
4580         gnu_attribute_t  *attributes = NULL;
4581         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
4582
4583         if (entity == NULL)
4584                 return;
4585
4586         type_t *type;
4587         if (entity->kind == ENTITY_TYPEDEF) {
4588                 modifiers |= entity->typedefe.modifiers;
4589                 type       = entity->typedefe.type;
4590         } else {
4591                 assert(is_declaration(entity));
4592                 modifiers |= entity->declaration.modifiers;
4593                 type       = entity->declaration.type;
4594         }
4595         if (type == NULL)
4596                 return;
4597
4598         gnu_attribute_t *attribute = attributes;
4599         for ( ; attribute != NULL; attribute = attribute->next) {
4600                 if (attribute->invalid)
4601                         continue;
4602
4603                 if (attribute->kind == GNU_AK_MODE) {
4604                         type = handle_attribute_mode(attribute, type);
4605                 } else if (attribute->kind == GNU_AK_ALIGNED) {
4606                         int alignment = 32; /* TODO: fill in maximum usefull alignment for target machine */
4607                         if (attribute->has_arguments)
4608                                 alignment = attribute->u.argument;
4609
4610                         if (entity->kind == ENTITY_TYPEDEF) {
4611                                 type_t *copy         = duplicate_type(type);
4612                                 copy->base.alignment = attribute->u.argument;
4613                                 type                 = identify_new_type(copy);
4614                         } else if(entity->kind == ENTITY_VARIABLE) {
4615                                 entity->variable.alignment = alignment;
4616                         } else if(entity->kind == ENTITY_COMPOUND_MEMBER) {
4617                                 entity->compound_member.alignment = alignment;
4618                         }
4619                 }
4620         }
4621
4622         type_modifiers_t type_modifiers = type->base.modifiers;
4623         if (modifiers & DM_TRANSPARENT_UNION)
4624                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
4625
4626         if (type->base.modifiers != type_modifiers) {
4627                 type_t *copy         = duplicate_type(type);
4628                 copy->base.modifiers = type_modifiers;
4629                 type                 = identify_new_type(copy);
4630         }
4631
4632         if (entity->kind == ENTITY_TYPEDEF) {
4633                 entity->typedefe.type      = type;
4634                 entity->typedefe.modifiers = modifiers;
4635         } else {
4636                 entity->declaration.type      = type;
4637                 entity->declaration.modifiers = modifiers;
4638         }
4639 }
4640
4641 static type_t *construct_declarator_type(construct_type_t *construct_list, type_t *type)
4642 {
4643         construct_type_t *iter = construct_list;
4644         for (; iter != NULL; iter = iter->base.next) {
4645                 switch (iter->kind) {
4646                 case CONSTRUCT_INVALID:
4647                         break;
4648                 case CONSTRUCT_FUNCTION: {
4649                         construct_function_type_t *function      = &iter->function;
4650                         type_t                    *function_type = function->function_type;
4651
4652                         function_type->function.return_type = type;
4653
4654                         type_t *skipped_return_type = skip_typeref(type);
4655                         /* §6.7.5.3:1 */
4656                         if (is_type_function(skipped_return_type)) {
4657                                 errorf(HERE, "function returning function is not allowed");
4658                         } else if (is_type_array(skipped_return_type)) {
4659                                 errorf(HERE, "function returning array is not allowed");
4660                         } else {
4661                                 if (skipped_return_type->base.qualifiers != 0 && warning.other) {
4662                                         warningf(HERE,
4663                                                 "type qualifiers in return type of function type are meaningless");
4664                                 }
4665                         }
4666
4667                         /* The function type was constructed earlier.  Freeing it here will
4668                          * destroy other types. */
4669                         type = typehash_insert(function_type);
4670                         continue;
4671                 }
4672
4673                 case CONSTRUCT_POINTER: {
4674                         if (is_type_reference(skip_typeref(type)))
4675                                 errorf(HERE, "cannot declare a pointer to reference");
4676
4677                         parsed_pointer_t *pointer = &iter->pointer;
4678                         type = make_based_pointer_type(type, pointer->type_qualifiers, pointer->base_variable);
4679                         continue;
4680                 }
4681
4682                 case CONSTRUCT_REFERENCE:
4683                         if (is_type_reference(skip_typeref(type)))
4684                                 errorf(HERE, "cannot declare a reference to reference");
4685
4686                         type = make_reference_type(type);
4687                         continue;
4688
4689                 case CONSTRUCT_ARRAY: {
4690                         if (is_type_reference(skip_typeref(type)))
4691                                 errorf(HERE, "cannot declare an array of references");
4692
4693                         parsed_array_t *array      = &iter->array;
4694                         type_t         *array_type = allocate_type_zero(TYPE_ARRAY);
4695
4696                         expression_t *size_expression = array->size;
4697                         if (size_expression != NULL) {
4698                                 size_expression
4699                                         = create_implicit_cast(size_expression, type_size_t);
4700                         }
4701
4702                         array_type->base.qualifiers       = array->type_qualifiers;
4703                         array_type->array.element_type    = type;
4704                         array_type->array.is_static       = array->is_static;
4705                         array_type->array.is_variable     = array->is_variable;
4706                         array_type->array.size_expression = size_expression;
4707
4708                         if (size_expression != NULL) {
4709                                 if (is_constant_expression(size_expression)) {
4710                                         long const size                 = fold_constant(size_expression);
4711                                         array_type->array.size          = size;
4712                                         array_type->array.size_constant = true;
4713                                         /* §6.7.5.2:1  If the expression is a constant expression, it shall
4714                                          * have a value greater than zero. */
4715                                         if (size <= 0) {
4716                                                 if (size < 0 || !GNU_MODE) {
4717                                                         errorf(&size_expression->base.source_position,
4718                                                                         "size of array must be greater than zero");
4719                                                 } else if (warning.other) {
4720                                                         warningf(&size_expression->base.source_position,
4721                                                                         "zero length arrays are a GCC extension");
4722                                                 }
4723                                         }
4724                                 } else {
4725                                         array_type->array.is_vla = true;
4726                                 }
4727                         }
4728
4729                         type_t *skipped_type = skip_typeref(type);
4730                         /* §6.7.5.2:1 */
4731                         if (is_type_incomplete(skipped_type)) {
4732                                 errorf(HERE, "array of incomplete type '%T' is not allowed", type);
4733                         } else if (is_type_function(skipped_type)) {
4734                                 errorf(HERE, "array of functions is not allowed");
4735                         }
4736                         type = identify_new_type(array_type);
4737                         continue;
4738                 }
4739                 }
4740                 internal_errorf(HERE, "invalid type construction found");
4741         }
4742
4743         return type;
4744 }
4745
4746 static type_t *automatic_type_conversion(type_t *orig_type);
4747
4748 static type_t *semantic_parameter(const source_position_t *pos,
4749                                   type_t *type,
4750                                   const declaration_specifiers_t *specifiers,
4751                                   symbol_t *symbol)
4752 {
4753         /* §6.7.5.3:7  A declaration of a parameter as ``array of type''
4754          *             shall be adjusted to ``qualified pointer to type'',
4755          *             [...]
4756          * §6.7.5.3:8  A declaration of a parameter as ``function returning
4757          *             type'' shall be adjusted to ``pointer to function
4758          *             returning type'', as in 6.3.2.1. */
4759         type = automatic_type_conversion(type);
4760
4761         if (specifiers->is_inline && is_type_valid(type)) {
4762                 errorf(pos, "parameter '%#T' declared 'inline'", type, symbol);
4763         }
4764
4765         /* §6.9.1:6  The declarations in the declaration list shall contain
4766          *           no storage-class specifier other than register and no
4767          *           initializations. */
4768         if (specifiers->thread_local || (
4769                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4770                         specifiers->storage_class != STORAGE_CLASS_REGISTER)
4771            ) {
4772                 errorf(pos, "invalid storage class for parameter '%#T'", type, symbol);
4773         }
4774
4775         /* delay test for incomplete type, because we might have (void)
4776          * which is legal but incomplete... */
4777
4778         return type;
4779 }
4780
4781 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
4782                                   declarator_flags_t flags)
4783 {
4784         parse_declarator_env_t env;
4785         memset(&env, 0, sizeof(env));
4786         env.modifiers = specifiers->modifiers;
4787
4788         construct_type_t *construct_type =
4789                 parse_inner_declarator(&env, (flags & DECL_MAY_BE_ABSTRACT) != 0);
4790         type_t           *orig_type      =
4791                 construct_declarator_type(construct_type, specifiers->type);
4792         type_t           *type           = skip_typeref(orig_type);
4793
4794         if (construct_type != NULL) {
4795                 obstack_free(&temp_obst, construct_type);
4796         }
4797
4798         entity_t *entity;
4799         if (specifiers->storage_class == STORAGE_CLASS_TYPEDEF) {
4800                 entity                       = allocate_entity_zero(ENTITY_TYPEDEF);
4801                 entity->base.symbol          = env.symbol;
4802                 entity->base.source_position = env.source_position;
4803                 entity->typedefe.type        = orig_type;
4804
4805                 if (anonymous_entity != NULL) {
4806                         if (is_type_compound(type)) {
4807                                 assert(anonymous_entity->compound.alias == NULL);
4808                                 assert(anonymous_entity->kind == ENTITY_STRUCT ||
4809                                        anonymous_entity->kind == ENTITY_UNION);
4810                                 anonymous_entity->compound.alias = entity;
4811                                 anonymous_entity = NULL;
4812                         } else if (is_type_enum(type)) {
4813                                 assert(anonymous_entity->enume.alias == NULL);
4814                                 assert(anonymous_entity->kind == ENTITY_ENUM);
4815                                 anonymous_entity->enume.alias = entity;
4816                                 anonymous_entity = NULL;
4817                         }
4818                 }
4819         } else {
4820                 /* create a declaration type entity */
4821                 if (flags & DECL_CREATE_COMPOUND_MEMBER) {
4822                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
4823
4824                         if (env.symbol != NULL) {
4825                                 if (specifiers->is_inline && is_type_valid(type)) {
4826                                         errorf(&env.source_position,
4827                                                         "compound member '%Y' declared 'inline'", env.symbol);
4828                                 }
4829
4830                                 if (specifiers->thread_local ||
4831                                                 specifiers->storage_class != STORAGE_CLASS_NONE) {
4832                                         errorf(&env.source_position,
4833                                                         "compound member '%Y' must have no storage class",
4834                                                         env.symbol);
4835                                 }
4836                         }
4837                 } else if (flags & DECL_IS_PARAMETER) {
4838                         orig_type = semantic_parameter(&env.source_position, orig_type,
4839                                                        specifiers, env.symbol);
4840
4841                         entity = allocate_entity_zero(ENTITY_PARAMETER);
4842                 } else if (is_type_function(type)) {
4843                         entity = allocate_entity_zero(ENTITY_FUNCTION);
4844
4845                         entity->function.is_inline  = specifiers->is_inline;
4846                         entity->function.parameters = env.parameters;
4847
4848                         if (env.symbol != NULL) {
4849                                 if (specifiers->thread_local || (
4850                                                         specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4851                                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4852                                                         specifiers->storage_class != STORAGE_CLASS_STATIC
4853                                                 )) {
4854                                         errorf(&env.source_position,
4855                                                         "invalid storage class for function '%Y'", env.symbol);
4856                                 }
4857                         }
4858                 } else {
4859                         entity = allocate_entity_zero(ENTITY_VARIABLE);
4860
4861                         entity->variable.get_property_sym = specifiers->get_property_sym;
4862                         entity->variable.put_property_sym = specifiers->put_property_sym;
4863
4864                         entity->variable.thread_local = specifiers->thread_local;
4865
4866                         if (env.symbol != NULL) {
4867                                 if (specifiers->is_inline && is_type_valid(type)) {
4868                                         errorf(&env.source_position,
4869                                                         "variable '%Y' declared 'inline'", env.symbol);
4870                                 }
4871
4872                                 bool invalid_storage_class = false;
4873                                 if (current_scope == file_scope) {
4874                                         if (specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4875                                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4876                                                         specifiers->storage_class != STORAGE_CLASS_STATIC) {
4877                                                 invalid_storage_class = true;
4878                                         }
4879                                 } else {
4880                                         if (specifiers->thread_local &&
4881                                                         specifiers->storage_class == STORAGE_CLASS_NONE) {
4882                                                 invalid_storage_class = true;
4883                                         }
4884                                 }
4885                                 if (invalid_storage_class) {
4886                                         errorf(&env.source_position,
4887                                                         "invalid storage class for variable '%Y'", env.symbol);
4888                                 }
4889                         }
4890                 }
4891
4892                 if (env.symbol != NULL) {
4893                         entity->base.symbol          = env.symbol;
4894                         entity->base.source_position = env.source_position;
4895                 } else {
4896                         entity->base.source_position = specifiers->source_position;
4897                 }
4898                 entity->base.namespc                  = NAMESPACE_NORMAL;
4899                 entity->declaration.type              = orig_type;
4900                 entity->declaration.modifiers         = env.modifiers;
4901                 entity->declaration.deprecated_string = specifiers->deprecated_string;
4902
4903                 storage_class_t storage_class = specifiers->storage_class;
4904                 entity->declaration.declared_storage_class = storage_class;
4905
4906                 if (storage_class == STORAGE_CLASS_NONE && current_scope != file_scope)
4907                         storage_class = STORAGE_CLASS_AUTO;
4908                 entity->declaration.storage_class = storage_class;
4909         }
4910
4911         parse_declaration_attributes(entity);
4912
4913         return entity;
4914 }
4915
4916 static type_t *parse_abstract_declarator(type_t *base_type)
4917 {
4918         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4919
4920         type_t *result = construct_declarator_type(construct_type, base_type);
4921         if (construct_type != NULL) {
4922                 obstack_free(&temp_obst, construct_type);
4923         }
4924
4925         return result;
4926 }
4927
4928 /**
4929  * Check if the declaration of main is suspicious.  main should be a
4930  * function with external linkage, returning int, taking either zero
4931  * arguments, two, or three arguments of appropriate types, ie.
4932  *
4933  * int main([ int argc, char **argv [, char **env ] ]).
4934  *
4935  * @param decl    the declaration to check
4936  * @param type    the function type of the declaration
4937  */
4938 static void check_type_of_main(const entity_t *entity)
4939 {
4940         const source_position_t *pos = &entity->base.source_position;
4941         if (entity->kind != ENTITY_FUNCTION) {
4942                 warningf(pos, "'main' is not a function");
4943                 return;
4944         }
4945
4946         if (entity->declaration.storage_class == STORAGE_CLASS_STATIC) {
4947                 warningf(pos, "'main' is normally a non-static function");
4948         }
4949
4950         type_t *type = skip_typeref(entity->declaration.type);
4951         assert(is_type_function(type));
4952
4953         function_type_t *func_type = &type->function;
4954         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4955                 warningf(pos, "return type of 'main' should be 'int', but is '%T'",
4956                          func_type->return_type);
4957         }
4958         const function_parameter_t *parm = func_type->parameters;
4959         if (parm != NULL) {
4960                 type_t *const first_type = parm->type;
4961                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4962                         warningf(pos,
4963                                  "first argument of 'main' should be 'int', but is '%T'",
4964                                  first_type);
4965                 }
4966                 parm = parm->next;
4967                 if (parm != NULL) {
4968                         type_t *const second_type = parm->type;
4969                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4970                                 warningf(pos, "second argument of 'main' should be 'char**', but is '%T'", second_type);
4971                         }
4972                         parm = parm->next;
4973                         if (parm != NULL) {
4974                                 type_t *const third_type = parm->type;
4975                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4976                                         warningf(pos, "third argument of 'main' should be 'char**', but is '%T'", third_type);
4977                                 }
4978                                 parm = parm->next;
4979                                 if (parm != NULL)
4980                                         goto warn_arg_count;
4981                         }
4982                 } else {
4983 warn_arg_count:
4984                         warningf(pos, "'main' takes only zero, two or three arguments");
4985                 }
4986         }
4987 }
4988
4989 /**
4990  * Check if a symbol is the equal to "main".
4991  */
4992 static bool is_sym_main(const symbol_t *const sym)
4993 {
4994         return strcmp(sym->string, "main") == 0;
4995 }
4996
4997 static void error_redefined_as_different_kind(const source_position_t *pos,
4998                 const entity_t *old, entity_kind_t new_kind)
4999 {
5000         errorf(pos, "redeclaration of %s '%Y' as %s (declared %P)",
5001                get_entity_kind_name(old->kind), old->base.symbol,
5002                get_entity_kind_name(new_kind), &old->base.source_position);
5003 }
5004
5005 static bool is_error_entity(entity_t *const ent)
5006 {
5007         if (is_declaration(ent)) {
5008                 return is_type_valid(skip_typeref(ent->declaration.type));
5009         } else if (ent->kind == ENTITY_TYPEDEF) {
5010                 return is_type_valid(skip_typeref(ent->typedefe.type));
5011         }
5012         return false;
5013 }
5014
5015 /**
5016  * record entities for the NAMESPACE_NORMAL, and produce error messages/warnings
5017  * for various problems that occur for multiple definitions
5018  */
5019 static entity_t *record_entity(entity_t *entity, const bool is_definition)
5020 {
5021         const symbol_t *const    symbol  = entity->base.symbol;
5022         const namespace_tag_t    namespc = (namespace_tag_t)entity->base.namespc;
5023         const source_position_t *pos     = &entity->base.source_position;
5024
5025         /* can happen in error cases */
5026         if (symbol == NULL)
5027                 return entity;
5028
5029         entity_t *const previous_entity = get_entity(symbol, namespc);
5030         /* pushing the same entity twice will break the stack structure */
5031         assert(previous_entity != entity);
5032
5033         if (entity->kind == ENTITY_FUNCTION) {
5034                 type_t *const orig_type = entity->declaration.type;
5035                 type_t *const type      = skip_typeref(orig_type);
5036
5037                 assert(is_type_function(type));
5038                 if (type->function.unspecified_parameters &&
5039                                 warning.strict_prototypes &&
5040                                 previous_entity == NULL) {
5041                         warningf(pos, "function declaration '%#T' is not a prototype",
5042                                          orig_type, symbol);
5043                 }
5044
5045                 if (warning.main && current_scope == file_scope
5046                                 && is_sym_main(symbol)) {
5047                         check_type_of_main(entity);
5048                 }
5049         }
5050
5051         if (is_declaration(entity) &&
5052                         warning.nested_externs &&
5053                         entity->declaration.storage_class == STORAGE_CLASS_EXTERN &&
5054                         current_scope != file_scope) {
5055                 warningf(pos, "nested extern declaration of '%#T'",
5056                          entity->declaration.type, symbol);
5057         }
5058
5059         if (previous_entity != NULL) {
5060                 if (previous_entity->base.parent_scope == &current_function->parameters &&
5061                                 previous_entity->base.parent_scope->depth + 1 == current_scope->depth) {
5062                         assert(previous_entity->kind == ENTITY_PARAMETER);
5063                         errorf(pos,
5064                                         "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
5065                                         entity->declaration.type, symbol,
5066                                         previous_entity->declaration.type, symbol,
5067                                         &previous_entity->base.source_position);
5068                         goto finish;
5069                 }
5070
5071                 if (previous_entity->base.parent_scope == current_scope) {
5072                         if (previous_entity->kind != entity->kind) {
5073                                 if (!is_error_entity(previous_entity) && !is_error_entity(entity)) {
5074                                         error_redefined_as_different_kind(pos, previous_entity,
5075                                                         entity->kind);
5076                                 }
5077                                 goto finish;
5078                         }
5079                         if (previous_entity->kind == ENTITY_ENUM_VALUE) {
5080                                 errorf(pos, "redeclaration of enum entry '%Y' (declared %P)",
5081                                                 symbol, &previous_entity->base.source_position);
5082                                 goto finish;
5083                         }
5084                         if (previous_entity->kind == ENTITY_TYPEDEF) {
5085                                 /* TODO: C++ allows this for exactly the same type */
5086                                 errorf(pos, "redefinition of typedef '%Y' (declared %P)",
5087                                                 symbol, &previous_entity->base.source_position);
5088                                 goto finish;
5089                         }
5090
5091                         /* at this point we should have only VARIABLES or FUNCTIONS */
5092                         assert(is_declaration(previous_entity) && is_declaration(entity));
5093
5094                         declaration_t *const prev_decl = &previous_entity->declaration;
5095                         declaration_t *const decl      = &entity->declaration;
5096
5097                         /* can happen for K&R style declarations */
5098                         if (prev_decl->type       == NULL             &&
5099                                         previous_entity->kind == ENTITY_PARAMETER &&
5100                                         entity->kind          == ENTITY_PARAMETER) {
5101                                 prev_decl->type                   = decl->type;
5102                                 prev_decl->storage_class          = decl->storage_class;
5103                                 prev_decl->declared_storage_class = decl->declared_storage_class;
5104                                 prev_decl->modifiers              = decl->modifiers;
5105                                 prev_decl->deprecated_string      = decl->deprecated_string;
5106                                 return previous_entity;
5107                         }
5108
5109                         type_t *const orig_type = decl->type;
5110                         assert(orig_type != NULL);
5111                         type_t *const type      = skip_typeref(orig_type);
5112                         type_t *const prev_type = skip_typeref(prev_decl->type);
5113
5114                         if (!types_compatible(type, prev_type)) {
5115                                 errorf(pos,
5116                                                 "declaration '%#T' is incompatible with '%#T' (declared %P)",
5117                                                 orig_type, symbol, prev_decl->type, symbol,
5118                                                 &previous_entity->base.source_position);
5119                         } else {
5120                                 unsigned old_storage_class = prev_decl->storage_class;
5121                                 if (warning.redundant_decls               &&
5122                                                 is_definition                     &&
5123                                                 !prev_decl->used                  &&
5124                                                 !(prev_decl->modifiers & DM_USED) &&
5125                                                 prev_decl->storage_class == STORAGE_CLASS_STATIC) {
5126                                         warningf(&previous_entity->base.source_position,
5127                                                         "unnecessary static forward declaration for '%#T'",
5128                                                         prev_decl->type, symbol);
5129                                 }
5130
5131                                 storage_class_t new_storage_class = decl->storage_class;
5132
5133                                 /* pretend no storage class means extern for function
5134                                  * declarations (except if the previous declaration is neither
5135                                  * none nor extern) */
5136                                 if (entity->kind == ENTITY_FUNCTION) {
5137                                         /* the previous declaration could have unspecified parameters or
5138                                          * be a typedef, so use the new type */
5139                                         if (prev_type->function.unspecified_parameters || is_definition)
5140                                                 prev_decl->type = type;
5141
5142                                         switch (old_storage_class) {
5143                                                 case STORAGE_CLASS_NONE:
5144                                                         old_storage_class = STORAGE_CLASS_EXTERN;
5145                                                         /* FALLTHROUGH */
5146
5147                                                 case STORAGE_CLASS_EXTERN:
5148                                                         if (is_definition) {
5149                                                                 if (warning.missing_prototypes &&
5150                                                                                 prev_type->function.unspecified_parameters &&
5151                                                                                 !is_sym_main(symbol)) {
5152                                                                         warningf(pos, "no previous prototype for '%#T'",
5153                                                                                         orig_type, symbol);
5154                                                                 }
5155                                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
5156                                                                 new_storage_class = STORAGE_CLASS_EXTERN;
5157                                                         }
5158                                                         break;
5159
5160                                                 default:
5161                                                         break;
5162                                         }
5163                                 } else if (is_type_incomplete(prev_type)) {
5164                                         prev_decl->type = type;
5165                                 }
5166
5167                                 if (old_storage_class == STORAGE_CLASS_EXTERN &&
5168                                                 new_storage_class == STORAGE_CLASS_EXTERN) {
5169 warn_redundant_declaration:
5170                                         if (!is_definition           &&
5171                                                         warning.redundant_decls  &&
5172                                                         is_type_valid(prev_type) &&
5173                                                         strcmp(previous_entity->base.source_position.input_name,
5174                                                                 "<builtin>") != 0) {
5175                                                 warningf(pos,
5176                                                                 "redundant declaration for '%Y' (declared %P)",
5177                                                                 symbol, &previous_entity->base.source_position);
5178                                         }
5179                                 } else if (current_function == NULL) {
5180                                         if (old_storage_class != STORAGE_CLASS_STATIC &&
5181                                                         new_storage_class == STORAGE_CLASS_STATIC) {
5182                                                 errorf(pos,
5183                                                                 "static declaration of '%Y' follows non-static declaration (declared %P)",
5184                                                                 symbol, &previous_entity->base.source_position);
5185                                         } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
5186                                                 prev_decl->storage_class          = STORAGE_CLASS_NONE;
5187                                                 prev_decl->declared_storage_class = STORAGE_CLASS_NONE;
5188                                         } else {
5189                                                 /* ISO/IEC 14882:1998(E) §C.1.2:1 */
5190                                                 if (c_mode & _CXX)
5191                                                         goto error_redeclaration;
5192                                                 goto warn_redundant_declaration;
5193                                         }
5194                                 } else if (is_type_valid(prev_type)) {
5195                                         if (old_storage_class == new_storage_class) {
5196 error_redeclaration:
5197                                                 errorf(pos, "redeclaration of '%Y' (declared %P)",
5198                                                                 symbol, &previous_entity->base.source_position);
5199                                         } else {
5200                                                 errorf(pos,
5201                                                                 "redeclaration of '%Y' with different linkage (declared %P)",
5202                                                                 symbol, &previous_entity->base.source_position);
5203                                         }
5204                                 }
5205                         }
5206
5207                         prev_decl->modifiers |= decl->modifiers;
5208                         if (entity->kind == ENTITY_FUNCTION) {
5209                                 previous_entity->function.is_inline |= entity->function.is_inline;
5210                         }
5211                         return previous_entity;
5212                 }
5213
5214                 if (warning.shadow) {
5215                         warningf(pos, "%s '%Y' shadows %s (declared %P)",
5216                                         get_entity_kind_name(entity->kind), symbol,
5217                                         get_entity_kind_name(previous_entity->kind),
5218                                         &previous_entity->base.source_position);
5219                 }
5220         }
5221
5222         if (entity->kind == ENTITY_FUNCTION) {
5223                 if (is_definition &&
5224                                 entity->declaration.storage_class != STORAGE_CLASS_STATIC) {
5225                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
5226                                 warningf(pos, "no previous prototype for '%#T'",
5227                                          entity->declaration.type, symbol);
5228                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
5229                                 warningf(pos, "no previous declaration for '%#T'",
5230                                          entity->declaration.type, symbol);
5231                         }
5232                 }
5233         } else if (warning.missing_declarations &&
5234                         entity->kind == ENTITY_VARIABLE &&
5235                         current_scope == file_scope) {
5236                 declaration_t *declaration = &entity->declaration;
5237                 if (declaration->storage_class == STORAGE_CLASS_NONE) {
5238                         warningf(pos, "no previous declaration for '%#T'",
5239                                  declaration->type, symbol);
5240                 }
5241         }
5242
5243 finish:
5244         assert(entity->base.parent_scope == NULL);
5245         assert(current_scope != NULL);
5246
5247         entity->base.parent_scope = current_scope;
5248         entity->base.namespc      = NAMESPACE_NORMAL;
5249         environment_push(entity);
5250         append_entity(current_scope, entity);
5251
5252         return entity;
5253 }
5254
5255 static void parser_error_multiple_definition(entity_t *entity,
5256                 const source_position_t *source_position)
5257 {
5258         errorf(source_position, "multiple definition of '%Y' (declared %P)",
5259                entity->base.symbol, &entity->base.source_position);
5260 }
5261
5262 static bool is_declaration_specifier(const token_t *token,
5263                                      bool only_specifiers_qualifiers)
5264 {
5265         switch (token->type) {
5266                 TYPE_SPECIFIERS
5267                 TYPE_QUALIFIERS
5268                         return true;
5269                 case T_IDENTIFIER:
5270                         return is_typedef_symbol(token->v.symbol);
5271
5272                 case T___extension__:
5273                 STORAGE_CLASSES
5274                         return !only_specifiers_qualifiers;
5275
5276                 default:
5277                         return false;
5278         }
5279 }
5280
5281 static void parse_init_declarator_rest(entity_t *entity)
5282 {
5283         assert(is_declaration(entity));
5284         declaration_t *const declaration = &entity->declaration;
5285
5286         eat('=');
5287
5288         type_t *orig_type = declaration->type;
5289         type_t *type      = skip_typeref(orig_type);
5290
5291         if (entity->kind == ENTITY_VARIABLE
5292                         && entity->variable.initializer != NULL) {
5293                 parser_error_multiple_definition(entity, HERE);
5294         }
5295
5296         bool must_be_constant = false;
5297         if (declaration->storage_class == STORAGE_CLASS_STATIC ||
5298             entity->base.parent_scope  == file_scope) {
5299                 must_be_constant = true;
5300         }
5301
5302         if (is_type_function(type)) {
5303                 errorf(&entity->base.source_position,
5304                        "function '%#T' is initialized like a variable",
5305                        orig_type, entity->base.symbol);
5306                 orig_type = type_error_type;
5307         }
5308
5309         parse_initializer_env_t env;
5310         env.type             = orig_type;
5311         env.must_be_constant = must_be_constant;
5312         env.entity           = entity;
5313         current_init_decl    = entity;
5314
5315         initializer_t *initializer = parse_initializer(&env);
5316         current_init_decl = NULL;
5317
5318         if (entity->kind == ENTITY_VARIABLE) {
5319                 /* §6.7.5:22  array initializers for arrays with unknown size
5320                  * determine the array type size */
5321                 declaration->type            = env.type;
5322                 entity->variable.initializer = initializer;
5323         }
5324 }
5325
5326 /* parse rest of a declaration without any declarator */
5327 static void parse_anonymous_declaration_rest(
5328                 const declaration_specifiers_t *specifiers)
5329 {
5330         eat(';');
5331         anonymous_entity = NULL;
5332
5333         if (warning.other) {
5334                 if (specifiers->storage_class != STORAGE_CLASS_NONE ||
5335                                 specifiers->thread_local) {
5336                         warningf(&specifiers->source_position,
5337                                  "useless storage class in empty declaration");
5338                 }
5339
5340                 type_t *type = specifiers->type;
5341                 switch (type->kind) {
5342                         case TYPE_COMPOUND_STRUCT:
5343                         case TYPE_COMPOUND_UNION: {
5344                                 if (type->compound.compound->base.symbol == NULL) {
5345                                         warningf(&specifiers->source_position,
5346                                                  "unnamed struct/union that defines no instances");
5347                                 }
5348                                 break;
5349                         }
5350
5351                         case TYPE_ENUM:
5352                                 break;
5353
5354                         default:
5355                                 warningf(&specifiers->source_position, "empty declaration");
5356                                 break;
5357                 }
5358         }
5359 }
5360
5361 static void check_variable_type_complete(entity_t *ent)
5362 {
5363         if (ent->kind != ENTITY_VARIABLE)
5364                 return;
5365
5366         /* §6.7:7  If an identifier for an object is declared with no linkage, the
5367          *         type for the object shall be complete [...] */
5368         declaration_t *decl = &ent->declaration;
5369         if (decl->storage_class == STORAGE_CLASS_EXTERN ||
5370                         decl->storage_class == STORAGE_CLASS_STATIC)
5371                 return;
5372
5373         type_t *const orig_type = decl->type;
5374         type_t *const type      = skip_typeref(orig_type);
5375         if (!is_type_incomplete(type))
5376                 return;
5377
5378         /* §6.9.2:2 and §6.9.2:5: At the end of the translation incomplete arrays
5379          * are given length one. */
5380         if (is_type_array(type) && ent->base.parent_scope == file_scope) {
5381                 ARR_APP1(declaration_t*, incomplete_arrays, decl);
5382                 return;
5383         }
5384
5385         errorf(&ent->base.source_position, "variable '%#T' has incomplete type",
5386                         orig_type, ent->base.symbol);
5387 }
5388
5389
5390 static void parse_declaration_rest(entity_t *ndeclaration,
5391                 const declaration_specifiers_t *specifiers,
5392                 parsed_declaration_func         finished_declaration,
5393                 declarator_flags_t              flags)
5394 {
5395         add_anchor_token(';');
5396         add_anchor_token(',');
5397         while (true) {
5398                 entity_t *entity = finished_declaration(ndeclaration, token.type == '=');
5399
5400                 if (token.type == '=') {
5401                         parse_init_declarator_rest(entity);
5402                 } else if (entity->kind == ENTITY_VARIABLE) {
5403                         /* ISO/IEC 14882:1998(E) §8.5.3:3  The initializer can be omitted
5404                          * [...] where the extern specifier is explicitly used. */
5405                         declaration_t *decl = &entity->declaration;
5406                         if (decl->storage_class != STORAGE_CLASS_EXTERN) {
5407                                 type_t *type = decl->type;
5408                                 if (is_type_reference(skip_typeref(type))) {
5409                                         errorf(&entity->base.source_position,
5410                                                         "reference '%#T' must be initialized",
5411                                                         type, entity->base.symbol);
5412                                 }
5413                         }
5414                 }
5415
5416                 check_variable_type_complete(entity);
5417
5418                 if (token.type != ',')
5419                         break;
5420                 eat(',');
5421
5422                 add_anchor_token('=');
5423                 ndeclaration = parse_declarator(specifiers, flags);
5424                 rem_anchor_token('=');
5425         }
5426         expect(';', end_error);
5427
5428 end_error:
5429         anonymous_entity = NULL;
5430         rem_anchor_token(';');
5431         rem_anchor_token(',');
5432 }
5433
5434 static entity_t *finished_kr_declaration(entity_t *entity, bool is_definition)
5435 {
5436         symbol_t *symbol = entity->base.symbol;
5437         if (symbol == NULL) {
5438                 errorf(HERE, "anonymous declaration not valid as function parameter");
5439                 return entity;
5440         }
5441
5442         assert(entity->base.namespc == NAMESPACE_NORMAL);
5443         entity_t *previous_entity = get_entity(symbol, NAMESPACE_NORMAL);
5444         if (previous_entity == NULL
5445                         || previous_entity->base.parent_scope != current_scope) {
5446                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
5447                        symbol);
5448                 return entity;
5449         }
5450
5451         if (is_definition) {
5452                 errorf(HERE, "parameter '%Y' is initialised", entity->base.symbol);
5453         }
5454
5455         return record_entity(entity, false);
5456 }
5457
5458 static void parse_declaration(parsed_declaration_func finished_declaration,
5459                               declarator_flags_t      flags)
5460 {
5461         declaration_specifiers_t specifiers;
5462         memset(&specifiers, 0, sizeof(specifiers));
5463
5464         add_anchor_token(';');
5465         parse_declaration_specifiers(&specifiers);
5466         rem_anchor_token(';');
5467
5468         if (token.type == ';') {
5469                 parse_anonymous_declaration_rest(&specifiers);
5470         } else {
5471                 entity_t *entity = parse_declarator(&specifiers, flags);
5472                 parse_declaration_rest(entity, &specifiers, finished_declaration, flags);
5473         }
5474 }
5475
5476 static type_t *get_default_promoted_type(type_t *orig_type)
5477 {
5478         type_t *result = orig_type;
5479
5480         type_t *type = skip_typeref(orig_type);
5481         if (is_type_integer(type)) {
5482                 result = promote_integer(type);
5483         } else if (is_type_atomic(type, ATOMIC_TYPE_FLOAT)) {
5484                 result = type_double;
5485         }
5486
5487         return result;
5488 }
5489
5490 static void parse_kr_declaration_list(entity_t *entity)
5491 {
5492         if (entity->kind != ENTITY_FUNCTION)
5493                 return;
5494
5495         type_t *type = skip_typeref(entity->declaration.type);
5496         assert(is_type_function(type));
5497         if (!type->function.kr_style_parameters)
5498                 return;
5499
5500
5501         add_anchor_token('{');
5502
5503         /* push function parameters */
5504         size_t const  top       = environment_top();
5505         scope_t      *old_scope = scope_push(&entity->function.parameters);
5506
5507         entity_t *parameter = entity->function.parameters.entities;
5508         for ( ; parameter != NULL; parameter = parameter->base.next) {
5509                 assert(parameter->base.parent_scope == NULL);
5510                 parameter->base.parent_scope = current_scope;
5511                 environment_push(parameter);
5512         }
5513
5514         /* parse declaration list */
5515         for (;;) {
5516                 switch (token.type) {
5517                         DECLARATION_START
5518                         case T___extension__:
5519                         /* This covers symbols, which are no type, too, and results in
5520                          * better error messages.  The typical cases are misspelled type
5521                          * names and missing includes. */
5522                         case T_IDENTIFIER:
5523                                 parse_declaration(finished_kr_declaration, DECL_IS_PARAMETER);
5524                                 break;
5525                         default:
5526                                 goto decl_list_end;
5527                 }
5528         }
5529 decl_list_end:
5530
5531         /* pop function parameters */
5532         assert(current_scope == &entity->function.parameters);
5533         scope_pop(old_scope);
5534         environment_pop_to(top);
5535
5536         /* update function type */
5537         type_t *new_type = duplicate_type(type);
5538
5539         function_parameter_t  *parameters = NULL;
5540         function_parameter_t **anchor     = &parameters;
5541
5542         parameter = entity->function.parameters.entities;
5543         for (; parameter != NULL; parameter = parameter->base.next) {
5544                 if (parameter->kind != ENTITY_PARAMETER)
5545                         continue;
5546
5547                 type_t *parameter_type = parameter->declaration.type;
5548                 if (parameter_type == NULL) {
5549                         if (strict_mode) {
5550                                 errorf(HERE, "no type specified for function parameter '%Y'",
5551                                        parameter->base.symbol);
5552                         } else {
5553                                 if (warning.implicit_int) {
5554                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
5555                                                  parameter->base.symbol);
5556                                 }
5557                                 parameter_type              = type_int;
5558                                 parameter->declaration.type = parameter_type;
5559                         }
5560                 }
5561
5562                 semantic_parameter_incomplete(parameter);
5563                 parameter_type = parameter->declaration.type;
5564
5565                 /*
5566                  * we need the default promoted types for the function type
5567                  */
5568                 parameter_type = get_default_promoted_type(parameter_type);
5569
5570                 function_parameter_t *const parameter =
5571                         allocate_parameter(parameter_type);
5572
5573                 *anchor = parameter;
5574                 anchor  = &parameter->next;
5575         }
5576
5577         /* §6.9.1.7: A K&R style parameter list does NOT act as a function
5578          * prototype */
5579         new_type->function.parameters             = parameters;
5580         new_type->function.unspecified_parameters = true;
5581
5582         new_type = identify_new_type(new_type);
5583
5584         entity->declaration.type = new_type;
5585
5586         rem_anchor_token('{');
5587 }
5588
5589 static bool first_err = true;
5590
5591 /**
5592  * When called with first_err set, prints the name of the current function,
5593  * else does noting.
5594  */
5595 static void print_in_function(void)
5596 {
5597         if (first_err) {
5598                 first_err = false;
5599                 diagnosticf("%s: In function '%Y':\n",
5600                             current_function->base.base.source_position.input_name,
5601                             current_function->base.base.symbol);
5602         }
5603 }
5604
5605 /**
5606  * Check if all labels are defined in the current function.
5607  * Check if all labels are used in the current function.
5608  */
5609 static void check_labels(void)
5610 {
5611         for (const goto_statement_t *goto_statement = goto_first;
5612             goto_statement != NULL;
5613             goto_statement = goto_statement->next) {
5614                 /* skip computed gotos */
5615                 if (goto_statement->expression != NULL)
5616                         continue;
5617
5618                 label_t *label = goto_statement->label;
5619
5620                 label->used = true;
5621                 if (label->base.source_position.input_name == NULL) {
5622                         print_in_function();
5623                         errorf(&goto_statement->base.source_position,
5624                                "label '%Y' used but not defined", label->base.symbol);
5625                  }
5626         }
5627
5628         if (warning.unused_label) {
5629                 for (const label_statement_t *label_statement = label_first;
5630                          label_statement != NULL;
5631                          label_statement = label_statement->next) {
5632                         label_t *label = label_statement->label;
5633
5634                         if (! label->used) {
5635                                 print_in_function();
5636                                 warningf(&label_statement->base.source_position,
5637                                          "label '%Y' defined but not used", label->base.symbol);
5638                         }
5639                 }
5640         }
5641 }
5642
5643 static void warn_unused_entity(entity_t *entity, entity_t *last)
5644 {
5645         entity_t const *const end = last != NULL ? last->base.next : NULL;
5646         for (; entity != end; entity = entity->base.next) {
5647                 if (!is_declaration(entity))
5648                         continue;
5649
5650                 declaration_t *declaration = &entity->declaration;
5651                 if (declaration->implicit)
5652                         continue;
5653
5654                 if (!declaration->used) {
5655                         print_in_function();
5656                         const char *what = get_entity_kind_name(entity->kind);
5657                         warningf(&entity->base.source_position, "%s '%Y' is unused",
5658                                  what, entity->base.symbol);
5659                 } else if (entity->kind == ENTITY_VARIABLE && !entity->variable.read) {
5660                         print_in_function();
5661                         const char *what = get_entity_kind_name(entity->kind);
5662                         warningf(&entity->base.source_position, "%s '%Y' is never read",
5663                                  what, entity->base.symbol);
5664                 }
5665         }
5666 }
5667
5668 static void check_unused_variables(statement_t *const stmt, void *const env)
5669 {
5670         (void)env;
5671
5672         switch (stmt->kind) {
5673                 case STATEMENT_DECLARATION: {
5674                         declaration_statement_t const *const decls = &stmt->declaration;
5675                         warn_unused_entity(decls->declarations_begin,
5676                                            decls->declarations_end);
5677                         return;
5678                 }
5679
5680                 case STATEMENT_FOR:
5681                         warn_unused_entity(stmt->fors.scope.entities, NULL);
5682                         return;
5683
5684                 default:
5685                         return;
5686         }
5687 }
5688
5689 /**
5690  * Check declarations of current_function for unused entities.
5691  */
5692 static void check_declarations(void)
5693 {
5694         if (warning.unused_parameter) {
5695                 const scope_t *scope = &current_function->parameters;
5696
5697                 /* do not issue unused warnings for main */
5698                 if (!is_sym_main(current_function->base.base.symbol)) {
5699                         warn_unused_entity(scope->entities, NULL);
5700                 }
5701         }
5702         if (warning.unused_variable) {
5703                 walk_statements(current_function->statement, check_unused_variables,
5704                                 NULL);
5705         }
5706 }
5707
5708 static int determine_truth(expression_t const* const cond)
5709 {
5710         return
5711                 !is_constant_expression(cond) ? 0 :
5712                 fold_constant(cond) != 0      ? 1 :
5713                 -1;
5714 }
5715
5716 static void check_reachable(statement_t *);
5717 static bool reaches_end;
5718
5719 static bool expression_returns(expression_t const *const expr)
5720 {
5721         switch (expr->kind) {
5722                 case EXPR_CALL: {
5723                         expression_t const *const func = expr->call.function;
5724                         if (func->kind == EXPR_REFERENCE) {
5725                                 entity_t *entity = func->reference.entity;
5726                                 if (entity->kind == ENTITY_FUNCTION
5727                                                 && entity->declaration.modifiers & DM_NORETURN)
5728                                         return false;
5729                         }
5730
5731                         if (!expression_returns(func))
5732                                 return false;
5733
5734                         for (call_argument_t const* arg = expr->call.arguments; arg != NULL; arg = arg->next) {
5735                                 if (!expression_returns(arg->expression))
5736                                         return false;
5737                         }
5738
5739                         return true;
5740                 }
5741
5742                 case EXPR_REFERENCE:
5743                 case EXPR_REFERENCE_ENUM_VALUE:
5744                 case EXPR_CONST:
5745                 case EXPR_CHARACTER_CONSTANT:
5746                 case EXPR_WIDE_CHARACTER_CONSTANT:
5747                 case EXPR_STRING_LITERAL:
5748                 case EXPR_WIDE_STRING_LITERAL:
5749                 case EXPR_COMPOUND_LITERAL: // TODO descend into initialisers
5750                 case EXPR_LABEL_ADDRESS:
5751                 case EXPR_CLASSIFY_TYPE:
5752                 case EXPR_SIZEOF: // TODO handle obscure VLA case
5753                 case EXPR_ALIGNOF:
5754                 case EXPR_FUNCNAME:
5755                 case EXPR_BUILTIN_CONSTANT_P:
5756                 case EXPR_BUILTIN_TYPES_COMPATIBLE_P:
5757                 case EXPR_OFFSETOF:
5758                 case EXPR_INVALID:
5759                         return true;
5760
5761                 case EXPR_STATEMENT: {
5762                         bool old_reaches_end = reaches_end;
5763                         reaches_end = false;
5764                         check_reachable(expr->statement.statement);
5765                         bool returns = reaches_end;
5766                         reaches_end = old_reaches_end;
5767                         return returns;
5768                 }
5769
5770                 case EXPR_CONDITIONAL:
5771                         // TODO handle constant expression
5772
5773                         if (!expression_returns(expr->conditional.condition))
5774                                 return false;
5775
5776                         if (expr->conditional.true_expression != NULL
5777                                         && expression_returns(expr->conditional.true_expression))
5778                                 return true;
5779
5780                         return expression_returns(expr->conditional.false_expression);
5781
5782                 case EXPR_SELECT:
5783                         return expression_returns(expr->select.compound);
5784
5785                 case EXPR_ARRAY_ACCESS:
5786                         return
5787                                 expression_returns(expr->array_access.array_ref) &&
5788                                 expression_returns(expr->array_access.index);
5789
5790                 case EXPR_VA_START:
5791                         return expression_returns(expr->va_starte.ap);
5792
5793                 case EXPR_VA_ARG:
5794                         return expression_returns(expr->va_arge.ap);
5795
5796                 case EXPR_VA_COPY:
5797                         return expression_returns(expr->va_copye.src);
5798
5799                 EXPR_UNARY_CASES_MANDATORY
5800                         return expression_returns(expr->unary.value);
5801
5802                 case EXPR_UNARY_THROW:
5803                         return false;
5804
5805                 EXPR_BINARY_CASES
5806                         // TODO handle constant lhs of && and ||
5807                         return
5808                                 expression_returns(expr->binary.left) &&
5809                                 expression_returns(expr->binary.right);
5810
5811                 case EXPR_UNKNOWN:
5812                         break;
5813         }
5814
5815         panic("unhandled expression");
5816 }
5817
5818 static bool initializer_returns(initializer_t const *const init)
5819 {
5820         switch (init->kind) {
5821                 case INITIALIZER_VALUE:
5822                         return expression_returns(init->value.value);
5823
5824                 case INITIALIZER_LIST: {
5825                         initializer_t * const*       i       = init->list.initializers;
5826                         initializer_t * const* const end     = i + init->list.len;
5827                         bool                         returns = true;
5828                         for (; i != end; ++i) {
5829                                 if (!initializer_returns(*i))
5830                                         returns = false;
5831                         }
5832                         return returns;
5833                 }
5834
5835                 case INITIALIZER_STRING:
5836                 case INITIALIZER_WIDE_STRING:
5837                 case INITIALIZER_DESIGNATOR: // designators have no payload
5838                         return true;
5839         }
5840         panic("unhandled initializer");
5841 }
5842
5843 static bool noreturn_candidate;
5844
5845 static void check_reachable(statement_t *const stmt)
5846 {
5847         if (stmt->base.reachable)
5848                 return;
5849         if (stmt->kind != STATEMENT_DO_WHILE)
5850                 stmt->base.reachable = true;
5851
5852         statement_t *last = stmt;
5853         statement_t *next;
5854         switch (stmt->kind) {
5855                 case STATEMENT_INVALID:
5856                 case STATEMENT_EMPTY:
5857                 case STATEMENT_ASM:
5858                         next = stmt->base.next;
5859                         break;
5860
5861                 case STATEMENT_DECLARATION: {
5862                         declaration_statement_t const *const decl = &stmt->declaration;
5863                         entity_t                const *      ent  = decl->declarations_begin;
5864                         entity_t                const *const last = decl->declarations_end;
5865                         if (ent != NULL) {
5866                                 for (;; ent = ent->base.next) {
5867                                         if (ent->kind                 == ENTITY_VARIABLE &&
5868                                                         ent->variable.initializer != NULL            &&
5869                                                         !initializer_returns(ent->variable.initializer)) {
5870                                                 return;
5871                                         }
5872                                         if (ent == last)
5873                                                 break;
5874                                 }
5875                         }
5876                         next = stmt->base.next;
5877                         break;
5878                 }
5879
5880                 case STATEMENT_COMPOUND:
5881                         next = stmt->compound.statements;
5882                         if (next == NULL)
5883                                 next = stmt->base.next;
5884                         break;
5885
5886                 case STATEMENT_RETURN: {
5887                         expression_t const *const val = stmt->returns.value;
5888                         if (val == NULL || expression_returns(val))
5889                                 noreturn_candidate = false;
5890                         return;
5891                 }
5892
5893                 case STATEMENT_IF: {
5894                         if_statement_t const *const ifs  = &stmt->ifs;
5895                         expression_t   const *const cond = ifs->condition;
5896
5897                         if (!expression_returns(cond))
5898                                 return;
5899
5900                         int const val = determine_truth(cond);
5901
5902                         if (val >= 0)
5903                                 check_reachable(ifs->true_statement);
5904
5905                         if (val > 0)
5906                                 return;
5907
5908                         if (ifs->false_statement != NULL) {
5909                                 check_reachable(ifs->false_statement);
5910                                 return;
5911                         }
5912
5913                         next = stmt->base.next;
5914                         break;
5915                 }
5916
5917                 case STATEMENT_SWITCH: {
5918                         switch_statement_t const *const switchs = &stmt->switchs;
5919                         expression_t       const *const expr    = switchs->expression;
5920
5921                         if (!expression_returns(expr))
5922                                 return;
5923
5924                         if (is_constant_expression(expr)) {
5925                                 long                    const val      = fold_constant(expr);
5926                                 case_label_statement_t *      defaults = NULL;
5927                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5928                                         if (i->expression == NULL) {
5929                                                 defaults = i;
5930                                                 continue;
5931                                         }
5932
5933                                         if (i->first_case <= val && val <= i->last_case) {
5934                                                 check_reachable((statement_t*)i);
5935                                                 return;
5936                                         }
5937                                 }
5938
5939                                 if (defaults != NULL) {
5940                                         check_reachable((statement_t*)defaults);
5941                                         return;
5942                                 }
5943                         } else {
5944                                 bool has_default = false;
5945                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5946                                         if (i->expression == NULL)
5947                                                 has_default = true;
5948
5949                                         check_reachable((statement_t*)i);
5950                                 }
5951
5952                                 if (has_default)
5953                                         return;
5954                         }
5955
5956                         next = stmt->base.next;
5957                         break;
5958                 }
5959
5960                 case STATEMENT_EXPRESSION: {
5961                         /* Check for noreturn function call */
5962                         expression_t const *const expr = stmt->expression.expression;
5963                         if (!expression_returns(expr))
5964                                 return;
5965
5966                         next = stmt->base.next;
5967                         break;
5968                 }
5969
5970                 case STATEMENT_CONTINUE: {
5971                         statement_t *parent = stmt;
5972                         for (;;) {
5973                                 parent = parent->base.parent;
5974                                 if (parent == NULL) /* continue not within loop */
5975                                         return;
5976
5977                                 next = parent;
5978                                 switch (parent->kind) {
5979                                         case STATEMENT_WHILE:    goto continue_while;
5980                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5981                                         case STATEMENT_FOR:      goto continue_for;
5982
5983                                         default: break;
5984                                 }
5985                         }
5986                 }
5987
5988                 case STATEMENT_BREAK: {
5989                         statement_t *parent = stmt;
5990                         for (;;) {
5991                                 parent = parent->base.parent;
5992                                 if (parent == NULL) /* break not within loop/switch */
5993                                         return;
5994
5995                                 switch (parent->kind) {
5996                                         case STATEMENT_SWITCH:
5997                                         case STATEMENT_WHILE:
5998                                         case STATEMENT_DO_WHILE:
5999                                         case STATEMENT_FOR:
6000                                                 last = parent;
6001                                                 next = parent->base.next;
6002                                                 goto found_break_parent;
6003
6004                                         default: break;
6005                                 }
6006                         }
6007 found_break_parent:
6008                         break;
6009                 }
6010
6011                 case STATEMENT_GOTO:
6012                         if (stmt->gotos.expression) {
6013                                 if (!expression_returns(stmt->gotos.expression))
6014                                         return;
6015
6016                                 statement_t *parent = stmt->base.parent;
6017                                 if (parent == NULL) /* top level goto */
6018                                         return;
6019                                 next = parent;
6020                         } else {
6021                                 next = stmt->gotos.label->statement;
6022                                 if (next == NULL) /* missing label */
6023                                         return;
6024                         }
6025                         break;
6026
6027                 case STATEMENT_LABEL:
6028                         next = stmt->label.statement;
6029                         break;
6030
6031                 case STATEMENT_CASE_LABEL:
6032                         next = stmt->case_label.statement;
6033                         break;
6034
6035                 case STATEMENT_WHILE: {
6036                         while_statement_t const *const whiles = &stmt->whiles;
6037                         expression_t      const *const cond   = whiles->condition;
6038
6039                         if (!expression_returns(cond))
6040                                 return;
6041
6042                         int const val = determine_truth(cond);
6043
6044                         if (val >= 0)
6045                                 check_reachable(whiles->body);
6046
6047                         if (val > 0)
6048                                 return;
6049
6050                         next = stmt->base.next;
6051                         break;
6052                 }
6053
6054                 case STATEMENT_DO_WHILE:
6055                         next = stmt->do_while.body;
6056                         break;
6057
6058                 case STATEMENT_FOR: {
6059                         for_statement_t *const fors = &stmt->fors;
6060
6061                         if (fors->condition_reachable)
6062                                 return;
6063                         fors->condition_reachable = true;
6064
6065                         expression_t const *const cond = fors->condition;
6066
6067                         int val;
6068                         if (cond == NULL) {
6069                                 val = 1;
6070                         } else if (expression_returns(cond)) {
6071                                 val = determine_truth(cond);
6072                         } else {
6073                                 return;
6074                         }
6075
6076                         if (val >= 0)
6077                                 check_reachable(fors->body);
6078
6079                         if (val > 0)
6080                                 return;
6081
6082                         next = stmt->base.next;
6083                         break;
6084                 }
6085
6086                 case STATEMENT_MS_TRY: {
6087                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
6088                         check_reachable(ms_try->try_statement);
6089                         next = ms_try->final_statement;
6090                         break;
6091                 }
6092
6093                 case STATEMENT_LEAVE: {
6094                         statement_t *parent = stmt;
6095                         for (;;) {
6096                                 parent = parent->base.parent;
6097                                 if (parent == NULL) /* __leave not within __try */
6098                                         return;
6099
6100                                 if (parent->kind == STATEMENT_MS_TRY) {
6101                                         last = parent;
6102                                         next = parent->ms_try.final_statement;
6103                                         break;
6104                                 }
6105                         }
6106                         break;
6107                 }
6108
6109                 default:
6110                         panic("invalid statement kind");
6111         }
6112
6113         while (next == NULL) {
6114                 next = last->base.parent;
6115                 if (next == NULL) {
6116                         noreturn_candidate = false;
6117
6118                         type_t *const type = skip_typeref(current_function->base.type);
6119                         assert(is_type_function(type));
6120                         type_t *const ret  = skip_typeref(type->function.return_type);
6121                         if (warning.return_type                    &&
6122                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
6123                             is_type_valid(ret)                     &&
6124                             !is_sym_main(current_function->base.base.symbol)) {
6125                                 warningf(&stmt->base.source_position,
6126                                          "control reaches end of non-void function");
6127                         }
6128                         return;
6129                 }
6130
6131                 switch (next->kind) {
6132                         case STATEMENT_INVALID:
6133                         case STATEMENT_EMPTY:
6134                         case STATEMENT_DECLARATION:
6135                         case STATEMENT_EXPRESSION:
6136                         case STATEMENT_ASM:
6137                         case STATEMENT_RETURN:
6138                         case STATEMENT_CONTINUE:
6139                         case STATEMENT_BREAK:
6140                         case STATEMENT_GOTO:
6141                         case STATEMENT_LEAVE:
6142                                 panic("invalid control flow in function");
6143
6144                         case STATEMENT_COMPOUND:
6145                                 if (next->compound.stmt_expr) {
6146                                         reaches_end = true;
6147                                         return;
6148                                 }
6149                                 /* FALLTHROUGH */
6150                         case STATEMENT_IF:
6151                         case STATEMENT_SWITCH:
6152                         case STATEMENT_LABEL:
6153                         case STATEMENT_CASE_LABEL:
6154                                 last = next;
6155                                 next = next->base.next;
6156                                 break;
6157
6158                         case STATEMENT_WHILE: {
6159 continue_while:
6160                                 if (next->base.reachable)
6161                                         return;
6162                                 next->base.reachable = true;
6163
6164                                 while_statement_t const *const whiles = &next->whiles;
6165                                 expression_t      const *const cond   = whiles->condition;
6166
6167                                 if (!expression_returns(cond))
6168                                         return;
6169
6170                                 int const val = determine_truth(cond);
6171
6172                                 if (val >= 0)
6173                                         check_reachable(whiles->body);
6174
6175                                 if (val > 0)
6176                                         return;
6177
6178                                 last = next;
6179                                 next = next->base.next;
6180                                 break;
6181                         }
6182
6183                         case STATEMENT_DO_WHILE: {
6184 continue_do_while:
6185                                 if (next->base.reachable)
6186                                         return;
6187                                 next->base.reachable = true;
6188
6189                                 do_while_statement_t const *const dw   = &next->do_while;
6190                                 expression_t         const *const cond = dw->condition;
6191
6192                                 if (!expression_returns(cond))
6193                                         return;
6194
6195                                 int const val = determine_truth(cond);
6196
6197                                 if (val >= 0)
6198                                         check_reachable(dw->body);
6199
6200                                 if (val > 0)
6201                                         return;
6202
6203                                 last = next;
6204                                 next = next->base.next;
6205                                 break;
6206                         }
6207
6208                         case STATEMENT_FOR: {
6209 continue_for:;
6210                                 for_statement_t *const fors = &next->fors;
6211
6212                                 fors->step_reachable = true;
6213
6214                                 if (fors->condition_reachable)
6215                                         return;
6216                                 fors->condition_reachable = true;
6217
6218                                 expression_t const *const cond = fors->condition;
6219
6220                                 int val;
6221                                 if (cond == NULL) {
6222                                         val = 1;
6223                                 } else if (expression_returns(cond)) {
6224                                         val = determine_truth(cond);
6225                                 } else {
6226                                         return;
6227                                 }
6228
6229                                 if (val >= 0)
6230                                         check_reachable(fors->body);
6231
6232                                 if (val > 0)
6233                                         return;
6234
6235                                 last = next;
6236                                 next = next->base.next;
6237                                 break;
6238                         }
6239
6240                         case STATEMENT_MS_TRY:
6241                                 last = next;
6242                                 next = next->ms_try.final_statement;
6243                                 break;
6244                 }
6245         }
6246
6247         check_reachable(next);
6248 }
6249
6250 static void check_unreachable(statement_t* const stmt, void *const env)
6251 {
6252         (void)env;
6253
6254         switch (stmt->kind) {
6255                 case STATEMENT_DO_WHILE:
6256                         if (!stmt->base.reachable) {
6257                                 expression_t const *const cond = stmt->do_while.condition;
6258                                 if (determine_truth(cond) >= 0) {
6259                                         warningf(&cond->base.source_position,
6260                                                  "condition of do-while-loop is unreachable");
6261                                 }
6262                         }
6263                         return;
6264
6265                 case STATEMENT_FOR: {
6266                         for_statement_t const* const fors = &stmt->fors;
6267
6268                         // if init and step are unreachable, cond is unreachable, too
6269                         if (!stmt->base.reachable && !fors->step_reachable) {
6270                                 warningf(&stmt->base.source_position, "statement is unreachable");
6271                         } else {
6272                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
6273                                         warningf(&fors->initialisation->base.source_position,
6274                                                  "initialisation of for-statement is unreachable");
6275                                 }
6276
6277                                 if (!fors->condition_reachable && fors->condition != NULL) {
6278                                         warningf(&fors->condition->base.source_position,
6279                                                  "condition of for-statement is unreachable");
6280                                 }
6281
6282                                 if (!fors->step_reachable && fors->step != NULL) {
6283                                         warningf(&fors->step->base.source_position,
6284                                                  "step of for-statement is unreachable");
6285                                 }
6286                         }
6287                         return;
6288                 }
6289
6290                 case STATEMENT_COMPOUND:
6291                         if (stmt->compound.statements != NULL)
6292                                 return;
6293                         goto warn_unreachable;
6294
6295                 case STATEMENT_DECLARATION: {
6296                         /* Only warn if there is at least one declarator with an initializer.
6297                          * This typically occurs in switch statements. */
6298                         declaration_statement_t const *const decl = &stmt->declaration;
6299                         entity_t                const *      ent  = decl->declarations_begin;
6300                         entity_t                const *const last = decl->declarations_end;
6301                         if (ent != NULL) {
6302                                 for (;; ent = ent->base.next) {
6303                                         if (ent->kind                 == ENTITY_VARIABLE &&
6304                                                         ent->variable.initializer != NULL) {
6305                                                 goto warn_unreachable;
6306                                         }
6307                                         if (ent == last)
6308                                                 return;
6309                                 }
6310                         }
6311                 }
6312
6313                 default:
6314 warn_unreachable:
6315                         if (!stmt->base.reachable)
6316                                 warningf(&stmt->base.source_position, "statement is unreachable");
6317                         return;
6318         }
6319 }
6320
6321 static void parse_external_declaration(void)
6322 {
6323         /* function-definitions and declarations both start with declaration
6324          * specifiers */
6325         declaration_specifiers_t specifiers;
6326         memset(&specifiers, 0, sizeof(specifiers));
6327
6328         add_anchor_token(';');
6329         parse_declaration_specifiers(&specifiers);
6330         rem_anchor_token(';');
6331
6332         /* must be a declaration */
6333         if (token.type == ';') {
6334                 parse_anonymous_declaration_rest(&specifiers);
6335                 return;
6336         }
6337
6338         add_anchor_token(',');
6339         add_anchor_token('=');
6340         add_anchor_token(';');
6341         add_anchor_token('{');
6342
6343         /* declarator is common to both function-definitions and declarations */
6344         entity_t *ndeclaration = parse_declarator(&specifiers, DECL_FLAGS_NONE);
6345
6346         rem_anchor_token('{');
6347         rem_anchor_token(';');
6348         rem_anchor_token('=');
6349         rem_anchor_token(',');
6350
6351         /* must be a declaration */
6352         switch (token.type) {
6353                 case ',':
6354                 case ';':
6355                 case '=':
6356                         parse_declaration_rest(ndeclaration, &specifiers, record_entity,
6357                                         DECL_FLAGS_NONE);
6358                         return;
6359         }
6360
6361         /* must be a function definition */
6362         parse_kr_declaration_list(ndeclaration);
6363
6364         if (token.type != '{') {
6365                 parse_error_expected("while parsing function definition", '{', NULL);
6366                 eat_until_matching_token(';');
6367                 return;
6368         }
6369
6370         assert(is_declaration(ndeclaration));
6371         type_t *const orig_type = ndeclaration->declaration.type;
6372         type_t *      type      = skip_typeref(orig_type);
6373
6374         if (!is_type_function(type)) {
6375                 if (is_type_valid(type)) {
6376                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
6377                                type, ndeclaration->base.symbol);
6378                 }
6379                 eat_block();
6380                 return;
6381         } else if (is_typeref(orig_type)) {
6382                 /* §6.9.1:2 */
6383                 errorf(&ndeclaration->base.source_position,
6384                                 "type of function definition '%#T' is a typedef",
6385                                 orig_type, ndeclaration->base.symbol);
6386         }
6387
6388         if (warning.aggregate_return &&
6389             is_type_compound(skip_typeref(type->function.return_type))) {
6390                 warningf(HERE, "function '%Y' returns an aggregate",
6391                          ndeclaration->base.symbol);
6392         }
6393         if (warning.traditional && !type->function.unspecified_parameters) {
6394                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
6395                         ndeclaration->base.symbol);
6396         }
6397         if (warning.old_style_definition && type->function.unspecified_parameters) {
6398                 warningf(HERE, "old-style function definition '%Y'",
6399                         ndeclaration->base.symbol);
6400         }
6401
6402         /* §6.7.5.3:14 a function definition with () means no
6403          * parameters (and not unspecified parameters) */
6404         if (type->function.unspecified_parameters &&
6405                         type->function.parameters == NULL     &&
6406                         !type->function.kr_style_parameters) {
6407                 type_t *copy                          = duplicate_type(type);
6408                 copy->function.unspecified_parameters = false;
6409                 type                                  = identify_new_type(copy);
6410
6411                 ndeclaration->declaration.type = type;
6412         }
6413
6414         entity_t *const entity = record_entity(ndeclaration, true);
6415         assert(entity->kind == ENTITY_FUNCTION);
6416         assert(ndeclaration->kind == ENTITY_FUNCTION);
6417
6418         function_t *function = &entity->function;
6419         if (ndeclaration != entity) {
6420                 function->parameters = ndeclaration->function.parameters;
6421         }
6422         assert(is_declaration(entity));
6423         type = skip_typeref(entity->declaration.type);
6424
6425         /* push function parameters and switch scope */
6426         size_t const  top       = environment_top();
6427         scope_t      *old_scope = scope_push(&function->parameters);
6428
6429         entity_t *parameter = function->parameters.entities;
6430         for (; parameter != NULL; parameter = parameter->base.next) {
6431                 if (parameter->base.parent_scope == &ndeclaration->function.parameters) {
6432                         parameter->base.parent_scope = current_scope;
6433                 }
6434                 assert(parameter->base.parent_scope == NULL
6435                                 || parameter->base.parent_scope == current_scope);
6436                 parameter->base.parent_scope = current_scope;
6437                 if (parameter->base.symbol == NULL) {
6438                         errorf(&parameter->base.source_position, "parameter name omitted");
6439                         continue;
6440                 }
6441                 environment_push(parameter);
6442         }
6443
6444         if (function->statement != NULL) {
6445                 parser_error_multiple_definition(entity, HERE);
6446                 eat_block();
6447         } else {
6448                 /* parse function body */
6449                 int         label_stack_top      = label_top();
6450                 function_t *old_current_function = current_function;
6451                 current_function                 = function;
6452                 current_parent                   = NULL;
6453
6454                 goto_first   = NULL;
6455                 goto_anchor  = &goto_first;
6456                 label_first  = NULL;
6457                 label_anchor = &label_first;
6458
6459                 statement_t *const body = parse_compound_statement(false);
6460                 function->statement = body;
6461                 first_err = true;
6462                 check_labels();
6463                 check_declarations();
6464                 if (warning.return_type      ||
6465                     warning.unreachable_code ||
6466                     (warning.missing_noreturn
6467                      && !(function->base.modifiers & DM_NORETURN))) {
6468                         noreturn_candidate = true;
6469                         check_reachable(body);
6470                         if (warning.unreachable_code)
6471                                 walk_statements(body, check_unreachable, NULL);
6472                         if (warning.missing_noreturn &&
6473                             noreturn_candidate       &&
6474                             !(function->base.modifiers & DM_NORETURN)) {
6475                                 warningf(&body->base.source_position,
6476                                          "function '%#T' is candidate for attribute 'noreturn'",
6477                                          type, entity->base.symbol);
6478                         }
6479                 }
6480
6481                 assert(current_parent   == NULL);
6482                 assert(current_function == function);
6483                 current_function = old_current_function;
6484                 label_pop_to(label_stack_top);
6485         }
6486
6487         assert(current_scope == &function->parameters);
6488         scope_pop(old_scope);
6489         environment_pop_to(top);
6490 }
6491
6492 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
6493                                   source_position_t *source_position,
6494                                   const symbol_t *symbol)
6495 {
6496         type_t *type = allocate_type_zero(TYPE_BITFIELD);
6497
6498         type->bitfield.base_type       = base_type;
6499         type->bitfield.size_expression = size;
6500
6501         il_size_t bit_size;
6502         type_t *skipped_type = skip_typeref(base_type);
6503         if (!is_type_integer(skipped_type)) {
6504                 errorf(HERE, "bitfield base type '%T' is not an integer type",
6505                         base_type);
6506                 bit_size = 0;
6507         } else {
6508                 bit_size = skipped_type->base.size * 8;
6509         }
6510
6511         if (is_constant_expression(size)) {
6512                 long v = fold_constant(size);
6513
6514                 if (v < 0) {
6515                         errorf(source_position, "negative width in bit-field '%Y'", symbol);
6516                 } else if (v == 0) {
6517                         errorf(source_position, "zero width for bit-field '%Y'", symbol);
6518                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
6519                         errorf(source_position, "width of '%Y' exceeds its type", symbol);
6520                 } else {
6521                         type->bitfield.bit_size = v;
6522                 }
6523         }
6524
6525         return type;
6526 }
6527
6528 static entity_t *find_compound_entry(compound_t *compound, symbol_t *symbol)
6529 {
6530         entity_t *iter = compound->members.entities;
6531         for (; iter != NULL; iter = iter->base.next) {
6532                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
6533                         continue;
6534
6535                 if (iter->base.symbol == symbol) {
6536                         return iter;
6537                 } else if (iter->base.symbol == NULL) {
6538                         type_t *type = skip_typeref(iter->declaration.type);
6539                         if (is_type_compound(type)) {
6540                                 entity_t *result
6541                                         = find_compound_entry(type->compound.compound, symbol);
6542                                 if (result != NULL)
6543                                         return result;
6544                         }
6545                         continue;
6546                 }
6547         }
6548
6549         return NULL;
6550 }
6551
6552 static void parse_compound_declarators(compound_t *compound,
6553                 const declaration_specifiers_t *specifiers)
6554 {
6555         while (true) {
6556                 entity_t *entity;
6557
6558                 if (token.type == ':') {
6559                         source_position_t source_position = *HERE;
6560                         next_token();
6561
6562                         type_t *base_type = specifiers->type;
6563                         expression_t *size = parse_constant_expression();
6564
6565                         type_t *type = make_bitfield_type(base_type, size,
6566                                         &source_position, sym_anonymous);
6567
6568                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
6569                         entity->base.namespc                       = NAMESPACE_NORMAL;
6570                         entity->base.source_position               = source_position;
6571                         entity->declaration.declared_storage_class = STORAGE_CLASS_NONE;
6572                         entity->declaration.storage_class          = STORAGE_CLASS_NONE;
6573                         entity->declaration.modifiers              = specifiers->modifiers;
6574                         entity->declaration.type                   = type;
6575                         append_entity(&compound->members, entity);
6576                 } else {
6577                         entity = parse_declarator(specifiers,
6578                                         DECL_MAY_BE_ABSTRACT | DECL_CREATE_COMPOUND_MEMBER);
6579                         if (entity->kind == ENTITY_TYPEDEF) {
6580                                 errorf(&entity->base.source_position,
6581                                                 "typedef not allowed as compound member");
6582                         } else {
6583                                 assert(entity->kind == ENTITY_COMPOUND_MEMBER);
6584
6585                                 /* make sure we don't define a symbol multiple times */
6586                                 symbol_t *symbol = entity->base.symbol;
6587                                 if (symbol != NULL) {
6588                                         entity_t *prev = find_compound_entry(compound, symbol);
6589                                         if (prev != NULL) {
6590                                                 errorf(&entity->base.source_position,
6591                                                                 "multiple declarations of symbol '%Y' (declared %P)",
6592                                                                 symbol, &prev->base.source_position);
6593                                         }
6594                                 }
6595
6596                                 if (token.type == ':') {
6597                                         source_position_t source_position = *HERE;
6598                                         next_token();
6599                                         expression_t *size = parse_constant_expression();
6600
6601                                         type_t *type          = entity->declaration.type;
6602                                         type_t *bitfield_type = make_bitfield_type(type, size,
6603                                                         &source_position, entity->base.symbol);
6604                                         entity->declaration.type = bitfield_type;
6605                                 } else {
6606                                         type_t *orig_type = entity->declaration.type;
6607                                         type_t *type      = skip_typeref(orig_type);
6608                                         if (is_type_function(type)) {
6609                                                 errorf(&entity->base.source_position,
6610                                                                 "compound member '%Y' must not have function type '%T'",
6611                                                                 entity->base.symbol, orig_type);
6612                                         } else if (is_type_incomplete(type)) {
6613                                                 /* §6.7.2.1:16 flexible array member */
6614                                                 if (!is_type_array(type)       ||
6615                                                                 token.type          != ';' ||
6616                                                                 look_ahead(1)->type != '}') {
6617                                                         errorf(&entity->base.source_position,
6618                                                                         "compound member '%Y' has incomplete type '%T'",
6619                                                                         entity->base.symbol, orig_type);
6620                                                 }
6621                                         }
6622                                 }
6623
6624                                 append_entity(&compound->members, entity);
6625                         }
6626                 }
6627
6628                 if (token.type != ',')
6629                         break;
6630                 next_token();
6631         }
6632         expect(';', end_error);
6633
6634 end_error:
6635         anonymous_entity = NULL;
6636 }
6637
6638 static void parse_compound_type_entries(compound_t *compound)
6639 {
6640         eat('{');
6641         add_anchor_token('}');
6642
6643         while (token.type != '}') {
6644                 if (token.type == T_EOF) {
6645                         errorf(HERE, "EOF while parsing struct");
6646                         break;
6647                 }
6648                 declaration_specifiers_t specifiers;
6649                 memset(&specifiers, 0, sizeof(specifiers));
6650                 parse_declaration_specifiers(&specifiers);
6651
6652                 parse_compound_declarators(compound, &specifiers);
6653         }
6654         rem_anchor_token('}');
6655         next_token();
6656
6657         /* §6.7.2.1:7 */
6658         compound->complete = true;
6659 }
6660
6661 static type_t *parse_typename(void)
6662 {
6663         declaration_specifiers_t specifiers;
6664         memset(&specifiers, 0, sizeof(specifiers));
6665         parse_declaration_specifiers(&specifiers);
6666         if (specifiers.storage_class != STORAGE_CLASS_NONE ||
6667                         specifiers.thread_local) {
6668                 /* TODO: improve error message, user does probably not know what a
6669                  * storage class is...
6670                  */
6671                 errorf(HERE, "typename may not have a storage class");
6672         }
6673
6674         type_t *result = parse_abstract_declarator(specifiers.type);
6675
6676         return result;
6677 }
6678
6679
6680
6681
6682 typedef expression_t* (*parse_expression_function)(void);
6683 typedef expression_t* (*parse_expression_infix_function)(expression_t *left);
6684
6685 typedef struct expression_parser_function_t expression_parser_function_t;
6686 struct expression_parser_function_t {
6687         parse_expression_function        parser;
6688         precedence_t                     infix_precedence;
6689         parse_expression_infix_function  infix_parser;
6690 };
6691
6692 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
6693
6694 /**
6695  * Prints an error message if an expression was expected but not read
6696  */
6697 static expression_t *expected_expression_error(void)
6698 {
6699         /* skip the error message if the error token was read */
6700         if (token.type != T_ERROR) {
6701                 errorf(HERE, "expected expression, got token %K", &token);
6702         }
6703         next_token();
6704
6705         return create_invalid_expression();
6706 }
6707
6708 /**
6709  * Parse a string constant.
6710  */
6711 static expression_t *parse_string_const(void)
6712 {
6713         wide_string_t wres;
6714         if (token.type == T_STRING_LITERAL) {
6715                 string_t res = token.v.string;
6716                 next_token();
6717                 while (token.type == T_STRING_LITERAL) {
6718                         res = concat_strings(&res, &token.v.string);
6719                         next_token();
6720                 }
6721                 if (token.type != T_WIDE_STRING_LITERAL) {
6722                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
6723                         /* note: that we use type_char_ptr here, which is already the
6724                          * automatic converted type. revert_automatic_type_conversion
6725                          * will construct the array type */
6726                         cnst->base.type    = warning.write_strings ? type_const_char_ptr : type_char_ptr;
6727                         cnst->string.value = res;
6728                         return cnst;
6729                 }
6730
6731                 wres = concat_string_wide_string(&res, &token.v.wide_string);
6732         } else {
6733                 wres = token.v.wide_string;
6734         }
6735         next_token();
6736
6737         for (;;) {
6738                 switch (token.type) {
6739                         case T_WIDE_STRING_LITERAL:
6740                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
6741                                 break;
6742
6743                         case T_STRING_LITERAL:
6744                                 wres = concat_wide_string_string(&wres, &token.v.string);
6745                                 break;
6746
6747                         default: {
6748                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
6749                                 cnst->base.type         = warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
6750                                 cnst->wide_string.value = wres;
6751                                 return cnst;
6752                         }
6753                 }
6754                 next_token();
6755         }
6756 }
6757
6758 /**
6759  * Parse a boolean constant.
6760  */
6761 static expression_t *parse_bool_const(bool value)
6762 {
6763         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6764         cnst->base.type          = type_bool;
6765         cnst->conste.v.int_value = value;
6766
6767         next_token();
6768
6769         return cnst;
6770 }
6771
6772 /**
6773  * Parse an integer constant.
6774  */
6775 static expression_t *parse_int_const(void)
6776 {
6777         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6778         cnst->base.type          = token.datatype;
6779         cnst->conste.v.int_value = token.v.intvalue;
6780
6781         next_token();
6782
6783         return cnst;
6784 }
6785
6786 /**
6787  * Parse a character constant.
6788  */
6789 static expression_t *parse_character_constant(void)
6790 {
6791         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
6792         cnst->base.type          = token.datatype;
6793         cnst->conste.v.character = token.v.string;
6794
6795         if (cnst->conste.v.character.size != 1) {
6796                 if (!GNU_MODE) {
6797                         errorf(HERE, "more than 1 character in character constant");
6798                 } else if (warning.multichar) {
6799                         warningf(HERE, "multi-character character constant");
6800                 }
6801         }
6802         next_token();
6803
6804         return cnst;
6805 }
6806
6807 /**
6808  * Parse a wide character constant.
6809  */
6810 static expression_t *parse_wide_character_constant(void)
6811 {
6812         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
6813         cnst->base.type               = token.datatype;
6814         cnst->conste.v.wide_character = token.v.wide_string;
6815
6816         if (cnst->conste.v.wide_character.size != 1) {
6817                 if (!GNU_MODE) {
6818                         errorf(HERE, "more than 1 character in character constant");
6819                 } else if (warning.multichar) {
6820                         warningf(HERE, "multi-character character constant");
6821                 }
6822         }
6823         next_token();
6824
6825         return cnst;
6826 }
6827
6828 /**
6829  * Parse a float constant.
6830  */
6831 static expression_t *parse_float_const(void)
6832 {
6833         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6834         cnst->base.type            = token.datatype;
6835         cnst->conste.v.float_value = token.v.floatvalue;
6836
6837         next_token();
6838
6839         return cnst;
6840 }
6841
6842 static entity_t *create_implicit_function(symbol_t *symbol,
6843                 const source_position_t *source_position)
6844 {
6845         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION);
6846         ntype->function.return_type            = type_int;
6847         ntype->function.unspecified_parameters = true;
6848         ntype->function.linkage                = LINKAGE_C;
6849         type_t *type                           = identify_new_type(ntype);
6850
6851         entity_t *entity = allocate_entity_zero(ENTITY_FUNCTION);
6852         entity->declaration.storage_class          = STORAGE_CLASS_EXTERN;
6853         entity->declaration.declared_storage_class = STORAGE_CLASS_EXTERN;
6854         entity->declaration.type                   = type;
6855         entity->declaration.implicit               = true;
6856         entity->base.symbol                        = symbol;
6857         entity->base.source_position               = *source_position;
6858
6859         bool strict_prototypes_old = warning.strict_prototypes;
6860         warning.strict_prototypes  = false;
6861         record_entity(entity, false);
6862         warning.strict_prototypes = strict_prototypes_old;
6863
6864         return entity;
6865 }
6866
6867 /**
6868  * Creates a return_type (func)(argument_type) function type if not
6869  * already exists.
6870  */
6871 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
6872                                     type_t *argument_type2)
6873 {
6874         function_parameter_t *const parameter2 = allocate_parameter(argument_type2);
6875         function_parameter_t *const parameter1 = allocate_parameter(argument_type1);
6876         parameter1->next = parameter2;
6877
6878         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6879         type->function.return_type = return_type;
6880         type->function.parameters  = parameter1;
6881
6882         return identify_new_type(type);
6883 }
6884
6885 /**
6886  * Creates a return_type (func)(argument_type) function type if not
6887  * already exists.
6888  *
6889  * @param return_type    the return type
6890  * @param argument_type  the argument type
6891  */
6892 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
6893 {
6894         function_parameter_t *const parameter = allocate_parameter(argument_type);
6895
6896         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6897         type->function.return_type = return_type;
6898         type->function.parameters  = parameter;
6899
6900         return identify_new_type(type);
6901 }
6902
6903 static type_t *make_function_1_type_variadic(type_t *return_type, type_t *argument_type)
6904 {
6905         type_t *res = make_function_1_type(return_type, argument_type);
6906         res->function.variadic = 1;
6907         return res;
6908 }
6909
6910 /**
6911  * Creates a return_type (func)(void) function type if not
6912  * already exists.
6913  *
6914  * @param return_type    the return type
6915  */
6916 static type_t *make_function_0_type(type_t *return_type)
6917 {
6918         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6919         type->function.return_type = return_type;
6920         type->function.parameters  = NULL;
6921
6922         return identify_new_type(type);
6923 }
6924
6925 /**
6926  * Creates a NO_RETURN return_type (func)(void) function type if not
6927  * already exists.
6928  *
6929  * @param return_type    the return type
6930  */
6931 static type_t *make_function_0_type_noreturn(type_t *return_type)
6932 {
6933         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6934         type->function.return_type = return_type;
6935         type->function.parameters  = NULL;
6936         type->function.base.modifiers |= DM_NORETURN;
6937         return type;
6938
6939         return identify_new_type(type);
6940 }
6941
6942 /**
6943  * Performs automatic type cast as described in §6.3.2.1.
6944  *
6945  * @param orig_type  the original type
6946  */
6947 static type_t *automatic_type_conversion(type_t *orig_type)
6948 {
6949         type_t *type = skip_typeref(orig_type);
6950         if (is_type_array(type)) {
6951                 array_type_t *array_type   = &type->array;
6952                 type_t       *element_type = array_type->element_type;
6953                 unsigned      qualifiers   = array_type->base.qualifiers;
6954
6955                 return make_pointer_type(element_type, qualifiers);
6956         }
6957
6958         if (is_type_function(type)) {
6959                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6960         }
6961
6962         return orig_type;
6963 }
6964
6965 /**
6966  * reverts the automatic casts of array to pointer types and function
6967  * to function-pointer types as defined §6.3.2.1
6968  */
6969 type_t *revert_automatic_type_conversion(const expression_t *expression)
6970 {
6971         switch (expression->kind) {
6972                 case EXPR_REFERENCE: {
6973                         entity_t *entity = expression->reference.entity;
6974                         if (is_declaration(entity)) {
6975                                 return entity->declaration.type;
6976                         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6977                                 return entity->enum_value.enum_type;
6978                         } else {
6979                                 panic("no declaration or enum in reference");
6980                         }
6981                 }
6982
6983                 case EXPR_SELECT: {
6984                         entity_t *entity = expression->select.compound_entry;
6985                         assert(is_declaration(entity));
6986                         type_t   *type   = entity->declaration.type;
6987                         return get_qualified_type(type,
6988                                         expression->base.type->base.qualifiers);
6989                 }
6990
6991                 case EXPR_UNARY_DEREFERENCE: {
6992                         const expression_t *const value = expression->unary.value;
6993                         type_t             *const type  = skip_typeref(value->base.type);
6994                         if (!is_type_pointer(type))
6995                                 return type_error_type;
6996                         return type->pointer.points_to;
6997                 }
6998
6999                 case EXPR_ARRAY_ACCESS: {
7000                         const expression_t *array_ref = expression->array_access.array_ref;
7001                         type_t             *type_left = skip_typeref(array_ref->base.type);
7002                         if (!is_type_pointer(type_left))
7003                                 return type_error_type;
7004                         return type_left->pointer.points_to;
7005                 }
7006
7007                 case EXPR_STRING_LITERAL: {
7008                         size_t size = expression->string.value.size;
7009                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
7010                 }
7011
7012                 case EXPR_WIDE_STRING_LITERAL: {
7013                         size_t size = expression->wide_string.value.size;
7014                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
7015                 }
7016
7017                 case EXPR_COMPOUND_LITERAL:
7018                         return expression->compound_literal.type;
7019
7020                 default:
7021                         return expression->base.type;
7022         }
7023 }
7024
7025 static expression_t *parse_reference(void)
7026 {
7027         symbol_t *const symbol = token.v.symbol;
7028
7029         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
7030
7031         if (entity == NULL) {
7032                 if (!strict_mode && look_ahead(1)->type == '(') {
7033                         /* an implicitly declared function */
7034                         if (warning.error_implicit_function_declaration) {
7035                                 errorf(HERE, "implicit declaration of function '%Y'", symbol);
7036                         } else if (warning.implicit_function_declaration) {
7037                                 warningf(HERE, "implicit declaration of function '%Y'", symbol);
7038                         }
7039
7040                         entity = create_implicit_function(symbol, HERE);
7041                 } else {
7042                         errorf(HERE, "unknown identifier '%Y' found.", symbol);
7043                         entity = create_error_entity(symbol, ENTITY_VARIABLE);
7044                 }
7045         }
7046
7047         type_t *orig_type;
7048
7049         if (is_declaration(entity)) {
7050                 orig_type = entity->declaration.type;
7051         } else if (entity->kind == ENTITY_ENUM_VALUE) {
7052                 orig_type = entity->enum_value.enum_type;
7053         } else if (entity->kind == ENTITY_TYPEDEF) {
7054                 errorf(HERE, "encountered typedef name '%Y' while parsing expression",
7055                         symbol);
7056                 next_token();
7057                 return create_invalid_expression();
7058         } else {
7059                 panic("expected declaration or enum value in reference");
7060         }
7061
7062         /* we always do the auto-type conversions; the & and sizeof parser contains
7063          * code to revert this! */
7064         type_t *type = automatic_type_conversion(orig_type);
7065
7066         expression_kind_t kind = EXPR_REFERENCE;
7067         if (entity->kind == ENTITY_ENUM_VALUE)
7068                 kind = EXPR_REFERENCE_ENUM_VALUE;
7069
7070         expression_t *expression     = allocate_expression_zero(kind);
7071         expression->reference.entity = entity;
7072         expression->base.type        = type;
7073
7074         /* this declaration is used */
7075         if (is_declaration(entity)) {
7076                 entity->declaration.used = true;
7077         }
7078
7079         if (entity->base.parent_scope != file_scope
7080                 && entity->base.parent_scope->depth < current_function->parameters.depth
7081                 && is_type_valid(orig_type) && !is_type_function(orig_type)) {
7082                 if (entity->kind == ENTITY_VARIABLE) {
7083                         /* access of a variable from an outer function */
7084                         entity->variable.address_taken = true;
7085                 } else if (entity->kind == ENTITY_PARAMETER) {
7086                         entity->parameter.address_taken = true;
7087                 }
7088                 current_function->need_closure = true;
7089         }
7090
7091         /* check for deprecated functions */
7092         if (warning.deprecated_declarations
7093                 && is_declaration(entity)
7094                 && entity->declaration.modifiers & DM_DEPRECATED) {
7095                 declaration_t *declaration = &entity->declaration;
7096
7097                 char const *const prefix = entity->kind == ENTITY_FUNCTION ?
7098                         "function" : "variable";
7099
7100                 if (declaration->deprecated_string != NULL) {
7101                         warningf(HERE, "%s '%Y' is deprecated (declared %P): \"%s\"",
7102                                  prefix, entity->base.symbol, &entity->base.source_position,
7103                                  declaration->deprecated_string);
7104                 } else {
7105                         warningf(HERE, "%s '%Y' is deprecated (declared %P)", prefix,
7106                                  entity->base.symbol, &entity->base.source_position);
7107                 }
7108         }
7109
7110         if (warning.init_self && entity == current_init_decl && !in_type_prop
7111             && entity->kind == ENTITY_VARIABLE) {
7112                 current_init_decl = NULL;
7113                 warningf(HERE, "variable '%#T' is initialized by itself",
7114                          entity->declaration.type, entity->base.symbol);
7115         }
7116
7117         next_token();
7118         return expression;
7119 }
7120
7121 static bool semantic_cast(expression_t *cast)
7122 {
7123         expression_t            *expression      = cast->unary.value;
7124         type_t                  *orig_dest_type  = cast->base.type;
7125         type_t                  *orig_type_right = expression->base.type;
7126         type_t            const *dst_type        = skip_typeref(orig_dest_type);
7127         type_t            const *src_type        = skip_typeref(orig_type_right);
7128         source_position_t const *pos             = &cast->base.source_position;
7129
7130         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
7131         if (dst_type == type_void)
7132                 return true;
7133
7134         /* only integer and pointer can be casted to pointer */
7135         if (is_type_pointer(dst_type)  &&
7136             !is_type_pointer(src_type) &&
7137             !is_type_integer(src_type) &&
7138             is_type_valid(src_type)) {
7139                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
7140                 return false;
7141         }
7142
7143         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
7144                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
7145                 return false;
7146         }
7147
7148         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
7149                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
7150                 return false;
7151         }
7152
7153         if (warning.cast_qual &&
7154             is_type_pointer(src_type) &&
7155             is_type_pointer(dst_type)) {
7156                 type_t *src = skip_typeref(src_type->pointer.points_to);
7157                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
7158                 unsigned missing_qualifiers =
7159                         src->base.qualifiers & ~dst->base.qualifiers;
7160                 if (missing_qualifiers != 0) {
7161                         warningf(pos,
7162                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
7163                                  missing_qualifiers, orig_type_right);
7164                 }
7165         }
7166         return true;
7167 }
7168
7169 static expression_t *parse_compound_literal(type_t *type)
7170 {
7171         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
7172
7173         parse_initializer_env_t env;
7174         env.type             = type;
7175         env.entity           = NULL;
7176         env.must_be_constant = false;
7177         initializer_t *initializer = parse_initializer(&env);
7178         type = env.type;
7179
7180         expression->compound_literal.initializer = initializer;
7181         expression->compound_literal.type        = type;
7182         expression->base.type                    = automatic_type_conversion(type);
7183
7184         return expression;
7185 }
7186
7187 /**
7188  * Parse a cast expression.
7189  */
7190 static expression_t *parse_cast(void)
7191 {
7192         add_anchor_token(')');
7193
7194         source_position_t source_position = token.source_position;
7195
7196         type_t *type = parse_typename();
7197
7198         rem_anchor_token(')');
7199         expect(')', end_error);
7200
7201         if (token.type == '{') {
7202                 return parse_compound_literal(type);
7203         }
7204
7205         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
7206         cast->base.source_position = source_position;
7207
7208         expression_t *value = parse_sub_expression(PREC_CAST);
7209         cast->base.type   = type;
7210         cast->unary.value = value;
7211
7212         if (! semantic_cast(cast)) {
7213                 /* TODO: record the error in the AST. else it is impossible to detect it */
7214         }
7215
7216         return cast;
7217 end_error:
7218         return create_invalid_expression();
7219 }
7220
7221 /**
7222  * Parse a statement expression.
7223  */
7224 static expression_t *parse_statement_expression(void)
7225 {
7226         add_anchor_token(')');
7227
7228         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
7229
7230         statement_t *statement          = parse_compound_statement(true);
7231         statement->compound.stmt_expr   = true;
7232         expression->statement.statement = statement;
7233
7234         /* find last statement and use its type */
7235         type_t *type = type_void;
7236         const statement_t *stmt = statement->compound.statements;
7237         if (stmt != NULL) {
7238                 while (stmt->base.next != NULL)
7239                         stmt = stmt->base.next;
7240
7241                 if (stmt->kind == STATEMENT_EXPRESSION) {
7242                         type = stmt->expression.expression->base.type;
7243                 }
7244         } else if (warning.other) {
7245                 warningf(&expression->base.source_position, "empty statement expression ({})");
7246         }
7247         expression->base.type = type;
7248
7249         rem_anchor_token(')');
7250         expect(')', end_error);
7251
7252 end_error:
7253         return expression;
7254 }
7255
7256 /**
7257  * Parse a parenthesized expression.
7258  */
7259 static expression_t *parse_parenthesized_expression(void)
7260 {
7261         eat('(');
7262
7263         switch (token.type) {
7264         case '{':
7265                 /* gcc extension: a statement expression */
7266                 return parse_statement_expression();
7267
7268         TYPE_QUALIFIERS
7269         TYPE_SPECIFIERS
7270                 return parse_cast();
7271         case T_IDENTIFIER:
7272                 if (is_typedef_symbol(token.v.symbol)) {
7273                         return parse_cast();
7274                 }
7275         }
7276
7277         add_anchor_token(')');
7278         expression_t *result = parse_expression();
7279         result->base.parenthesized = true;
7280         rem_anchor_token(')');
7281         expect(')', end_error);
7282
7283 end_error:
7284         return result;
7285 }
7286
7287 static expression_t *parse_function_keyword(void)
7288 {
7289         /* TODO */
7290
7291         if (current_function == NULL) {
7292                 errorf(HERE, "'__func__' used outside of a function");
7293         }
7294
7295         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7296         expression->base.type     = type_char_ptr;
7297         expression->funcname.kind = FUNCNAME_FUNCTION;
7298
7299         next_token();
7300
7301         return expression;
7302 }
7303
7304 static expression_t *parse_pretty_function_keyword(void)
7305 {
7306         if (current_function == NULL) {
7307                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
7308         }
7309
7310         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7311         expression->base.type     = type_char_ptr;
7312         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
7313
7314         eat(T___PRETTY_FUNCTION__);
7315
7316         return expression;
7317 }
7318
7319 static expression_t *parse_funcsig_keyword(void)
7320 {
7321         if (current_function == NULL) {
7322                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
7323         }
7324
7325         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7326         expression->base.type     = type_char_ptr;
7327         expression->funcname.kind = FUNCNAME_FUNCSIG;
7328
7329         eat(T___FUNCSIG__);
7330
7331         return expression;
7332 }
7333
7334 static expression_t *parse_funcdname_keyword(void)
7335 {
7336         if (current_function == NULL) {
7337                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
7338         }
7339
7340         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7341         expression->base.type     = type_char_ptr;
7342         expression->funcname.kind = FUNCNAME_FUNCDNAME;
7343
7344         eat(T___FUNCDNAME__);
7345
7346         return expression;
7347 }
7348
7349 static designator_t *parse_designator(void)
7350 {
7351         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
7352         result->source_position = *HERE;
7353
7354         if (token.type != T_IDENTIFIER) {
7355                 parse_error_expected("while parsing member designator",
7356                                      T_IDENTIFIER, NULL);
7357                 return NULL;
7358         }
7359         result->symbol = token.v.symbol;
7360         next_token();
7361
7362         designator_t *last_designator = result;
7363         while (true) {
7364                 if (token.type == '.') {
7365                         next_token();
7366                         if (token.type != T_IDENTIFIER) {
7367                                 parse_error_expected("while parsing member designator",
7368                                                      T_IDENTIFIER, NULL);
7369                                 return NULL;
7370                         }
7371                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7372                         designator->source_position = *HERE;
7373                         designator->symbol          = token.v.symbol;
7374                         next_token();
7375
7376                         last_designator->next = designator;
7377                         last_designator       = designator;
7378                         continue;
7379                 }
7380                 if (token.type == '[') {
7381                         next_token();
7382                         add_anchor_token(']');
7383                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7384                         designator->source_position = *HERE;
7385                         designator->array_index     = parse_expression();
7386                         rem_anchor_token(']');
7387                         expect(']', end_error);
7388                         if (designator->array_index == NULL) {
7389                                 return NULL;
7390                         }
7391
7392                         last_designator->next = designator;
7393                         last_designator       = designator;
7394                         continue;
7395                 }
7396                 break;
7397         }
7398
7399         return result;
7400 end_error:
7401         return NULL;
7402 }
7403
7404 /**
7405  * Parse the __builtin_offsetof() expression.
7406  */
7407 static expression_t *parse_offsetof(void)
7408 {
7409         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
7410         expression->base.type    = type_size_t;
7411
7412         eat(T___builtin_offsetof);
7413
7414         expect('(', end_error);
7415         add_anchor_token(',');
7416         type_t *type = parse_typename();
7417         rem_anchor_token(',');
7418         expect(',', end_error);
7419         add_anchor_token(')');
7420         designator_t *designator = parse_designator();
7421         rem_anchor_token(')');
7422         expect(')', end_error);
7423
7424         expression->offsetofe.type       = type;
7425         expression->offsetofe.designator = designator;
7426
7427         type_path_t path;
7428         memset(&path, 0, sizeof(path));
7429         path.top_type = type;
7430         path.path     = NEW_ARR_F(type_path_entry_t, 0);
7431
7432         descend_into_subtype(&path);
7433
7434         if (!walk_designator(&path, designator, true)) {
7435                 return create_invalid_expression();
7436         }
7437
7438         DEL_ARR_F(path.path);
7439
7440         return expression;
7441 end_error:
7442         return create_invalid_expression();
7443 }
7444
7445 /**
7446  * Parses a _builtin_va_start() expression.
7447  */
7448 static expression_t *parse_va_start(void)
7449 {
7450         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
7451
7452         eat(T___builtin_va_start);
7453
7454         expect('(', end_error);
7455         add_anchor_token(',');
7456         expression->va_starte.ap = parse_assignment_expression();
7457         rem_anchor_token(',');
7458         expect(',', end_error);
7459         expression_t *const expr = parse_assignment_expression();
7460         if (expr->kind == EXPR_REFERENCE) {
7461                 entity_t *const entity = expr->reference.entity;
7462                 if (entity->base.parent_scope != &current_function->parameters
7463                                 || entity->base.next != NULL
7464                                 || entity->kind != ENTITY_PARAMETER) {
7465                         errorf(&expr->base.source_position,
7466                                "second argument of 'va_start' must be last parameter of the current function");
7467                 } else {
7468                         expression->va_starte.parameter = &entity->variable;
7469                 }
7470                 expect(')', end_error);
7471                 return expression;
7472         }
7473         expect(')', end_error);
7474 end_error:
7475         return create_invalid_expression();
7476 }
7477
7478 /**
7479  * Parses a __builtin_va_arg() expression.
7480  */
7481 static expression_t *parse_va_arg(void)
7482 {
7483         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
7484
7485         eat(T___builtin_va_arg);
7486
7487         expect('(', end_error);
7488         call_argument_t ap;
7489         ap.expression = parse_assignment_expression();
7490         expression->va_arge.ap = ap.expression;
7491         check_call_argument(type_valist, &ap, 1);
7492
7493         expect(',', end_error);
7494         expression->base.type = parse_typename();
7495         expect(')', end_error);
7496
7497         return expression;
7498 end_error:
7499         return create_invalid_expression();
7500 }
7501
7502 /**
7503  * Parses a __builtin_va_copy() expression.
7504  */
7505 static expression_t *parse_va_copy(void)
7506 {
7507         expression_t *expression = allocate_expression_zero(EXPR_VA_COPY);
7508
7509         eat(T___builtin_va_copy);
7510
7511         expect('(', end_error);
7512         expression_t *dst = parse_assignment_expression();
7513         assign_error_t error = semantic_assign(type_valist, dst);
7514         report_assign_error(error, type_valist, dst, "call argument 1",
7515                             &dst->base.source_position);
7516         expression->va_copye.dst = dst;
7517
7518         expect(',', end_error);
7519
7520         call_argument_t src;
7521         src.expression = parse_assignment_expression();
7522         check_call_argument(type_valist, &src, 2);
7523         expression->va_copye.src = src.expression;
7524         expect(')', end_error);
7525
7526         return expression;
7527 end_error:
7528         return create_invalid_expression();
7529 }
7530
7531 /**
7532  * Parses a __builtin_constant_p() expression.
7533  */
7534 static expression_t *parse_builtin_constant(void)
7535 {
7536         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
7537
7538         eat(T___builtin_constant_p);
7539
7540         expect('(', end_error);
7541         add_anchor_token(')');
7542         expression->builtin_constant.value = parse_assignment_expression();
7543         rem_anchor_token(')');
7544         expect(')', end_error);
7545         expression->base.type = type_int;
7546
7547         return expression;
7548 end_error:
7549         return create_invalid_expression();
7550 }
7551
7552 /**
7553  * Parses a __builtin_types_compatible_p() expression.
7554  */
7555 static expression_t *parse_builtin_types_compatible(void)
7556 {
7557         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_TYPES_COMPATIBLE_P);
7558
7559         eat(T___builtin_types_compatible_p);
7560
7561         expect('(', end_error);
7562         add_anchor_token(')');
7563         add_anchor_token(',');
7564         expression->builtin_types_compatible.left = parse_typename();
7565         rem_anchor_token(',');
7566         expect(',', end_error);
7567         expression->builtin_types_compatible.right = parse_typename();
7568         rem_anchor_token(')');
7569         expect(')', end_error);
7570         expression->base.type = type_int;
7571
7572         return expression;
7573 end_error:
7574         return create_invalid_expression();
7575 }
7576
7577 /**
7578  * Parses a __builtin_is_*() compare expression.
7579  */
7580 static expression_t *parse_compare_builtin(void)
7581 {
7582         expression_t *expression;
7583
7584         switch (token.type) {
7585         case T___builtin_isgreater:
7586                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
7587                 break;
7588         case T___builtin_isgreaterequal:
7589                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
7590                 break;
7591         case T___builtin_isless:
7592                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
7593                 break;
7594         case T___builtin_islessequal:
7595                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
7596                 break;
7597         case T___builtin_islessgreater:
7598                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
7599                 break;
7600         case T___builtin_isunordered:
7601                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
7602                 break;
7603         default:
7604                 internal_errorf(HERE, "invalid compare builtin found");
7605         }
7606         expression->base.source_position = *HERE;
7607         next_token();
7608
7609         expect('(', end_error);
7610         expression->binary.left = parse_assignment_expression();
7611         expect(',', end_error);
7612         expression->binary.right = parse_assignment_expression();
7613         expect(')', end_error);
7614
7615         type_t *const orig_type_left  = expression->binary.left->base.type;
7616         type_t *const orig_type_right = expression->binary.right->base.type;
7617
7618         type_t *const type_left  = skip_typeref(orig_type_left);
7619         type_t *const type_right = skip_typeref(orig_type_right);
7620         if (!is_type_float(type_left) && !is_type_float(type_right)) {
7621                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7622                         type_error_incompatible("invalid operands in comparison",
7623                                 &expression->base.source_position, orig_type_left, orig_type_right);
7624                 }
7625         } else {
7626                 semantic_comparison(&expression->binary);
7627         }
7628
7629         return expression;
7630 end_error:
7631         return create_invalid_expression();
7632 }
7633
7634 #if 0
7635 /**
7636  * Parses a __builtin_expect(, end_error) expression.
7637  */
7638 static expression_t *parse_builtin_expect(void, end_error)
7639 {
7640         expression_t *expression
7641                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
7642
7643         eat(T___builtin_expect);
7644
7645         expect('(', end_error);
7646         expression->binary.left = parse_assignment_expression();
7647         expect(',', end_error);
7648         expression->binary.right = parse_constant_expression();
7649         expect(')', end_error);
7650
7651         expression->base.type = expression->binary.left->base.type;
7652
7653         return expression;
7654 end_error:
7655         return create_invalid_expression();
7656 }
7657 #endif
7658
7659 /**
7660  * Parses a MS assume() expression.
7661  */
7662 static expression_t *parse_assume(void)
7663 {
7664         expression_t *expression = allocate_expression_zero(EXPR_UNARY_ASSUME);
7665
7666         eat(T__assume);
7667
7668         expect('(', end_error);
7669         add_anchor_token(')');
7670         expression->unary.value = parse_assignment_expression();
7671         rem_anchor_token(')');
7672         expect(')', end_error);
7673
7674         expression->base.type = type_void;
7675         return expression;
7676 end_error:
7677         return create_invalid_expression();
7678 }
7679
7680 /**
7681  * Return the declaration for a given label symbol or create a new one.
7682  *
7683  * @param symbol  the symbol of the label
7684  */
7685 static label_t *get_label(symbol_t *symbol)
7686 {
7687         entity_t *label;
7688         assert(current_function != NULL);
7689
7690         label = get_entity(symbol, NAMESPACE_LABEL);
7691         /* if we found a local label, we already created the declaration */
7692         if (label != NULL && label->kind == ENTITY_LOCAL_LABEL) {
7693                 if (label->base.parent_scope != current_scope) {
7694                         assert(label->base.parent_scope->depth < current_scope->depth);
7695                         current_function->goto_to_outer = true;
7696                 }
7697                 return &label->label;
7698         }
7699
7700         label = get_entity(symbol, NAMESPACE_LABEL);
7701         /* if we found a label in the same function, then we already created the
7702          * declaration */
7703         if (label != NULL
7704                         && label->base.parent_scope == &current_function->parameters) {
7705                 return &label->label;
7706         }
7707
7708         /* otherwise we need to create a new one */
7709         label               = allocate_entity_zero(ENTITY_LABEL);
7710         label->base.namespc = NAMESPACE_LABEL;
7711         label->base.symbol  = symbol;
7712
7713         label_push(label);
7714
7715         return &label->label;
7716 }
7717
7718 /**
7719  * Parses a GNU && label address expression.
7720  */
7721 static expression_t *parse_label_address(void)
7722 {
7723         source_position_t source_position = token.source_position;
7724         eat(T_ANDAND);
7725         if (token.type != T_IDENTIFIER) {
7726                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
7727                 goto end_error;
7728         }
7729         symbol_t *symbol = token.v.symbol;
7730         next_token();
7731
7732         label_t *label       = get_label(symbol);
7733         label->used          = true;
7734         label->address_taken = true;
7735
7736         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
7737         expression->base.source_position = source_position;
7738
7739         /* label address is threaten as a void pointer */
7740         expression->base.type           = type_void_ptr;
7741         expression->label_address.label = label;
7742         return expression;
7743 end_error:
7744         return create_invalid_expression();
7745 }
7746
7747 /**
7748  * Parse a microsoft __noop expression.
7749  */
7750 static expression_t *parse_noop_expression(void)
7751 {
7752         /* the result is a (int)0 */
7753         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
7754         cnst->base.type            = type_int;
7755         cnst->conste.v.int_value   = 0;
7756         cnst->conste.is_ms_noop    = true;
7757
7758         eat(T___noop);
7759
7760         if (token.type == '(') {
7761                 /* parse arguments */
7762                 eat('(');
7763                 add_anchor_token(')');
7764                 add_anchor_token(',');
7765
7766                 if (token.type != ')') {
7767                         while (true) {
7768                                 (void)parse_assignment_expression();
7769                                 if (token.type != ',')
7770                                         break;
7771                                 next_token();
7772                         }
7773                 }
7774         }
7775         rem_anchor_token(',');
7776         rem_anchor_token(')');
7777         expect(')', end_error);
7778
7779 end_error:
7780         return cnst;
7781 }
7782
7783 /**
7784  * Parses a primary expression.
7785  */
7786 static expression_t *parse_primary_expression(void)
7787 {
7788         switch (token.type) {
7789                 case T_false:                        return parse_bool_const(false);
7790                 case T_true:                         return parse_bool_const(true);
7791                 case T_INTEGER:                      return parse_int_const();
7792                 case T_CHARACTER_CONSTANT:           return parse_character_constant();
7793                 case T_WIDE_CHARACTER_CONSTANT:      return parse_wide_character_constant();
7794                 case T_FLOATINGPOINT:                return parse_float_const();
7795                 case T_STRING_LITERAL:
7796                 case T_WIDE_STRING_LITERAL:          return parse_string_const();
7797                 case T_IDENTIFIER:                   return parse_reference();
7798                 case T___FUNCTION__:
7799                 case T___func__:                     return parse_function_keyword();
7800                 case T___PRETTY_FUNCTION__:          return parse_pretty_function_keyword();
7801                 case T___FUNCSIG__:                  return parse_funcsig_keyword();
7802                 case T___FUNCDNAME__:                return parse_funcdname_keyword();
7803                 case T___builtin_offsetof:           return parse_offsetof();
7804                 case T___builtin_va_start:           return parse_va_start();
7805                 case T___builtin_va_arg:             return parse_va_arg();
7806                 case T___builtin_va_copy:            return parse_va_copy();
7807                 case T___builtin_isgreater:
7808                 case T___builtin_isgreaterequal:
7809                 case T___builtin_isless:
7810                 case T___builtin_islessequal:
7811                 case T___builtin_islessgreater:
7812                 case T___builtin_isunordered:        return parse_compare_builtin();
7813                 case T___builtin_constant_p:         return parse_builtin_constant();
7814                 case T___builtin_types_compatible_p: return parse_builtin_types_compatible();
7815                 case T__assume:                      return parse_assume();
7816                 case T_ANDAND:
7817                         if (GNU_MODE)
7818                                 return parse_label_address();
7819                         break;
7820
7821                 case '(':                            return parse_parenthesized_expression();
7822                 case T___noop:                       return parse_noop_expression();
7823         }
7824
7825         errorf(HERE, "unexpected token %K, expected an expression", &token);
7826         return create_invalid_expression();
7827 }
7828
7829 /**
7830  * Check if the expression has the character type and issue a warning then.
7831  */
7832 static void check_for_char_index_type(const expression_t *expression)
7833 {
7834         type_t       *const type      = expression->base.type;
7835         const type_t *const base_type = skip_typeref(type);
7836
7837         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
7838                         warning.char_subscripts) {
7839                 warningf(&expression->base.source_position,
7840                          "array subscript has type '%T'", type);
7841         }
7842 }
7843
7844 static expression_t *parse_array_expression(expression_t *left)
7845 {
7846         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
7847
7848         eat('[');
7849         add_anchor_token(']');
7850
7851         expression_t *inside = parse_expression();
7852
7853         type_t *const orig_type_left   = left->base.type;
7854         type_t *const orig_type_inside = inside->base.type;
7855
7856         type_t *const type_left   = skip_typeref(orig_type_left);
7857         type_t *const type_inside = skip_typeref(orig_type_inside);
7858
7859         type_t                    *return_type;
7860         array_access_expression_t *array_access = &expression->array_access;
7861         if (is_type_pointer(type_left)) {
7862                 return_type             = type_left->pointer.points_to;
7863                 array_access->array_ref = left;
7864                 array_access->index     = inside;
7865                 check_for_char_index_type(inside);
7866         } else if (is_type_pointer(type_inside)) {
7867                 return_type             = type_inside->pointer.points_to;
7868                 array_access->array_ref = inside;
7869                 array_access->index     = left;
7870                 array_access->flipped   = true;
7871                 check_for_char_index_type(left);
7872         } else {
7873                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
7874                         errorf(HERE,
7875                                 "array access on object with non-pointer types '%T', '%T'",
7876                                 orig_type_left, orig_type_inside);
7877                 }
7878                 return_type             = type_error_type;
7879                 array_access->array_ref = left;
7880                 array_access->index     = inside;
7881         }
7882
7883         expression->base.type = automatic_type_conversion(return_type);
7884
7885         rem_anchor_token(']');
7886         expect(']', end_error);
7887 end_error:
7888         return expression;
7889 }
7890
7891 static expression_t *parse_typeprop(expression_kind_t const kind)
7892 {
7893         expression_t  *tp_expression = allocate_expression_zero(kind);
7894         tp_expression->base.type     = type_size_t;
7895
7896         eat(kind == EXPR_SIZEOF ? T_sizeof : T___alignof__);
7897
7898         /* we only refer to a type property, mark this case */
7899         bool old     = in_type_prop;
7900         in_type_prop = true;
7901
7902         type_t       *orig_type;
7903         expression_t *expression;
7904         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
7905                 next_token();
7906                 add_anchor_token(')');
7907                 orig_type = parse_typename();
7908                 rem_anchor_token(')');
7909                 expect(')', end_error);
7910
7911                 if (token.type == '{') {
7912                         /* It was not sizeof(type) after all.  It is sizeof of an expression
7913                          * starting with a compound literal */
7914                         expression = parse_compound_literal(orig_type);
7915                         goto typeprop_expression;
7916                 }
7917         } else {
7918                 expression = parse_sub_expression(PREC_UNARY);
7919
7920 typeprop_expression:
7921                 tp_expression->typeprop.tp_expression = expression;
7922
7923                 orig_type = revert_automatic_type_conversion(expression);
7924                 expression->base.type = orig_type;
7925         }
7926
7927         tp_expression->typeprop.type   = orig_type;
7928         type_t const* const type       = skip_typeref(orig_type);
7929         char   const* const wrong_type =
7930                 GNU_MODE && is_type_atomic(type, ATOMIC_TYPE_VOID) ? NULL                  :
7931                 is_type_incomplete(type)                           ? "incomplete"          :
7932                 type->kind == TYPE_FUNCTION                        ? "function designator" :
7933                 type->kind == TYPE_BITFIELD                        ? "bitfield"            :
7934                 NULL;
7935         if (wrong_type != NULL) {
7936                 char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7937                 errorf(&tp_expression->base.source_position,
7938                                 "operand of %s expression must not be of %s type '%T'",
7939                                 what, wrong_type, orig_type);
7940         }
7941
7942 end_error:
7943         in_type_prop = old;
7944         return tp_expression;
7945 }
7946
7947 static expression_t *parse_sizeof(void)
7948 {
7949         return parse_typeprop(EXPR_SIZEOF);
7950 }
7951
7952 static expression_t *parse_alignof(void)
7953 {
7954         return parse_typeprop(EXPR_ALIGNOF);
7955 }
7956
7957 static expression_t *parse_select_expression(expression_t *compound)
7958 {
7959         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
7960         select->select.compound = compound;
7961
7962         assert(token.type == '.' || token.type == T_MINUSGREATER);
7963         bool is_pointer = (token.type == T_MINUSGREATER);
7964         next_token();
7965
7966         if (token.type != T_IDENTIFIER) {
7967                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
7968                 return select;
7969         }
7970         symbol_t *symbol = token.v.symbol;
7971         next_token();
7972
7973         type_t *const orig_type = compound->base.type;
7974         type_t *const type      = skip_typeref(orig_type);
7975
7976         type_t *type_left;
7977         bool    saw_error = false;
7978         if (is_type_pointer(type)) {
7979                 if (!is_pointer) {
7980                         errorf(HERE,
7981                                "request for member '%Y' in something not a struct or union, but '%T'",
7982                                symbol, orig_type);
7983                         saw_error = true;
7984                 }
7985                 type_left = skip_typeref(type->pointer.points_to);
7986         } else {
7987                 if (is_pointer && is_type_valid(type)) {
7988                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7989                         saw_error = true;
7990                 }
7991                 type_left = type;
7992         }
7993
7994         entity_t *entry;
7995         if (type_left->kind == TYPE_COMPOUND_STRUCT ||
7996             type_left->kind == TYPE_COMPOUND_UNION) {
7997                 compound_t *compound = type_left->compound.compound;
7998
7999                 if (!compound->complete) {
8000                         errorf(HERE, "request for member '%Y' of incomplete type '%T'",
8001                                symbol, type_left);
8002                         goto create_error_entry;
8003                 }
8004
8005                 entry = find_compound_entry(compound, symbol);
8006                 if (entry == NULL) {
8007                         errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
8008                         goto create_error_entry;
8009                 }
8010         } else {
8011                 if (is_type_valid(type_left) && !saw_error) {
8012                         errorf(HERE,
8013                                "request for member '%Y' in something not a struct or union, but '%T'",
8014                                symbol, type_left);
8015                 }
8016 create_error_entry:
8017                 entry = create_error_entity(symbol, ENTITY_COMPOUND_MEMBER);
8018         }
8019
8020         assert(is_declaration(entry));
8021         select->select.compound_entry = entry;
8022
8023         type_t *entry_type = entry->declaration.type;
8024         type_t *res_type
8025                 = get_qualified_type(entry_type, type_left->base.qualifiers);
8026
8027         /* we always do the auto-type conversions; the & and sizeof parser contains
8028          * code to revert this! */
8029         select->base.type = automatic_type_conversion(res_type);
8030
8031         type_t *skipped = skip_typeref(res_type);
8032         if (skipped->kind == TYPE_BITFIELD) {
8033                 select->base.type = skipped->bitfield.base_type;
8034         }
8035
8036         return select;
8037 }
8038
8039 static void check_call_argument(type_t          *expected_type,
8040                                 call_argument_t *argument, unsigned pos)
8041 {
8042         type_t         *expected_type_skip = skip_typeref(expected_type);
8043         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
8044         expression_t   *arg_expr           = argument->expression;
8045         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
8046
8047         /* handle transparent union gnu extension */
8048         if (is_type_union(expected_type_skip)
8049                         && (expected_type_skip->base.modifiers
8050                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
8051                 compound_t *union_decl  = expected_type_skip->compound.compound;
8052                 type_t     *best_type   = NULL;
8053                 entity_t   *entry       = union_decl->members.entities;
8054                 for ( ; entry != NULL; entry = entry->base.next) {
8055                         assert(is_declaration(entry));
8056                         type_t *decl_type = entry->declaration.type;
8057                         error = semantic_assign(decl_type, arg_expr);
8058                         if (error == ASSIGN_ERROR_INCOMPATIBLE
8059                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
8060                                 continue;
8061
8062                         if (error == ASSIGN_SUCCESS) {
8063                                 best_type = decl_type;
8064                         } else if (best_type == NULL) {
8065                                 best_type = decl_type;
8066                         }
8067                 }
8068
8069                 if (best_type != NULL) {
8070                         expected_type = best_type;
8071                 }
8072         }
8073
8074         error                = semantic_assign(expected_type, arg_expr);
8075         argument->expression = create_implicit_cast(arg_expr, expected_type);
8076
8077         if (error != ASSIGN_SUCCESS) {
8078                 /* report exact scope in error messages (like "in argument 3") */
8079                 char buf[64];
8080                 snprintf(buf, sizeof(buf), "call argument %u", pos);
8081                 report_assign_error(error, expected_type, arg_expr,     buf,
8082                                                         &arg_expr->base.source_position);
8083         } else if (warning.traditional || warning.conversion) {
8084                 type_t *const promoted_type = get_default_promoted_type(arg_type);
8085                 if (!types_compatible(expected_type_skip, promoted_type) &&
8086                     !types_compatible(expected_type_skip, type_void_ptr) &&
8087                     !types_compatible(type_void_ptr,      promoted_type)) {
8088                         /* Deliberately show the skipped types in this warning */
8089                         warningf(&arg_expr->base.source_position,
8090                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
8091                                 pos, expected_type_skip, promoted_type);
8092                 }
8093         }
8094 }
8095
8096 /**
8097  * Handle the semantic restrictions of builtin calls
8098  */
8099 static void handle_builtin_argument_restrictions(call_expression_t *call) {
8100         switch (call->function->reference.entity->function.btk) {
8101                 case bk_gnu_builtin_return_address:
8102                 case bk_gnu_builtin_frame_address: {
8103                         /* argument must be constant */
8104                         call_argument_t *argument = call->arguments;
8105
8106                         if (! is_constant_expression(argument->expression)) {
8107                                 errorf(&call->base.source_position,
8108                                        "argument of '%Y' must be a constant expression",
8109                                        call->function->reference.entity->base.symbol);
8110                         }
8111                         break;
8112                 }
8113                 case bk_gnu_builtin_prefetch: {
8114                         /* second and third argument must be constant if existent */
8115                         call_argument_t *rw = call->arguments->next;
8116                         call_argument_t *locality = NULL;
8117
8118                         if (rw != NULL) {
8119                                 if (! is_constant_expression(rw->expression)) {
8120                                         errorf(&call->base.source_position,
8121                                                "second argument of '%Y' must be a constant expression",
8122                                                call->function->reference.entity->base.symbol);
8123                                 }
8124                                 locality = rw->next;
8125                         }
8126                         if (locality != NULL) {
8127                                 if (! is_constant_expression(locality->expression)) {
8128                                         errorf(&call->base.source_position,
8129                                                "third argument of '%Y' must be a constant expression",
8130                                                call->function->reference.entity->base.symbol);
8131                                 }
8132                                 locality = rw->next;
8133                         }
8134                         break;
8135                 }
8136                 default:
8137                         break;
8138         }
8139 }
8140
8141 /**
8142  * Parse a call expression, ie. expression '( ... )'.
8143  *
8144  * @param expression  the function address
8145  */
8146 static expression_t *parse_call_expression(expression_t *expression)
8147 {
8148         expression_t      *result = allocate_expression_zero(EXPR_CALL);
8149         call_expression_t *call   = &result->call;
8150         call->function            = expression;
8151
8152         type_t *const orig_type = expression->base.type;
8153         type_t *const type      = skip_typeref(orig_type);
8154
8155         function_type_t *function_type = NULL;
8156         if (is_type_pointer(type)) {
8157                 type_t *const to_type = skip_typeref(type->pointer.points_to);
8158
8159                 if (is_type_function(to_type)) {
8160                         function_type   = &to_type->function;
8161                         call->base.type = function_type->return_type;
8162                 }
8163         }
8164
8165         if (function_type == NULL && is_type_valid(type)) {
8166                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
8167         }
8168
8169         /* parse arguments */
8170         eat('(');
8171         add_anchor_token(')');
8172         add_anchor_token(',');
8173
8174         if (token.type != ')') {
8175                 call_argument_t **anchor = &call->arguments;
8176                 for (;;) {
8177                         call_argument_t *argument = allocate_ast_zero(sizeof(*argument));
8178                         argument->expression = parse_assignment_expression();
8179
8180                         *anchor = argument;
8181                         anchor  = &argument->next;
8182
8183                         if (token.type != ',')
8184                                 break;
8185                         next_token();
8186                 }
8187         }
8188         rem_anchor_token(',');
8189         rem_anchor_token(')');
8190         expect(')', end_error);
8191
8192         if (function_type == NULL)
8193                 return result;
8194
8195         function_parameter_t *parameter = function_type->parameters;
8196         call_argument_t      *argument  = call->arguments;
8197         if (!function_type->unspecified_parameters) {
8198                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
8199                                 parameter = parameter->next, argument = argument->next) {
8200                         check_call_argument(parameter->type, argument, ++pos);
8201                 }
8202
8203                 if (parameter != NULL) {
8204                         errorf(HERE, "too few arguments to function '%E'", expression);
8205                 } else if (argument != NULL && !function_type->variadic) {
8206                         errorf(HERE, "too many arguments to function '%E'", expression);
8207                 }
8208         }
8209
8210         /* do default promotion */
8211         for (; argument != NULL; argument = argument->next) {
8212                 type_t *type = argument->expression->base.type;
8213
8214                 type = get_default_promoted_type(type);
8215
8216                 argument->expression
8217                         = create_implicit_cast(argument->expression, type);
8218         }
8219
8220         check_format(&result->call);
8221
8222         if (warning.aggregate_return &&
8223             is_type_compound(skip_typeref(function_type->return_type))) {
8224                 warningf(&result->base.source_position,
8225                          "function call has aggregate value");
8226         }
8227
8228         if (call->function->kind == EXPR_REFERENCE) {
8229                 reference_expression_t *reference = &call->function->reference;
8230                 if (reference->entity->kind == ENTITY_FUNCTION &&
8231                     reference->entity->function.btk != bk_none)
8232                         handle_builtin_argument_restrictions(call);
8233         }
8234
8235 end_error:
8236         return result;
8237 }
8238
8239 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
8240
8241 static bool same_compound_type(const type_t *type1, const type_t *type2)
8242 {
8243         return
8244                 is_type_compound(type1) &&
8245                 type1->kind == type2->kind &&
8246                 type1->compound.compound == type2->compound.compound;
8247 }
8248
8249 static expression_t const *get_reference_address(expression_t const *expr)
8250 {
8251         bool regular_take_address = true;
8252         for (;;) {
8253                 if (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8254                         expr = expr->unary.value;
8255                 } else {
8256                         regular_take_address = false;
8257                 }
8258
8259                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8260                         break;
8261
8262                 expr = expr->unary.value;
8263         }
8264
8265         if (expr->kind != EXPR_REFERENCE)
8266                 return NULL;
8267
8268         /* special case for functions which are automatically converted to a
8269          * pointer to function without an extra TAKE_ADDRESS operation */
8270         if (!regular_take_address &&
8271                         expr->reference.entity->kind != ENTITY_FUNCTION) {
8272                 return NULL;
8273         }
8274
8275         return expr;
8276 }
8277
8278 static void warn_reference_address_as_bool(expression_t const* expr)
8279 {
8280         if (!warning.address)
8281                 return;
8282
8283         expr = get_reference_address(expr);
8284         if (expr != NULL) {
8285                 warningf(&expr->base.source_position,
8286                          "the address of '%Y' will always evaluate as 'true'",
8287                          expr->reference.entity->base.symbol);
8288         }
8289 }
8290
8291 static void warn_assignment_in_condition(const expression_t *const expr)
8292 {
8293         if (!warning.parentheses)
8294                 return;
8295         if (expr->base.kind != EXPR_BINARY_ASSIGN)
8296                 return;
8297         if (expr->base.parenthesized)
8298                 return;
8299         warningf(&expr->base.source_position,
8300                         "suggest parentheses around assignment used as truth value");
8301 }
8302
8303 static void semantic_condition(expression_t const *const expr,
8304                                char const *const context)
8305 {
8306         type_t *const type = skip_typeref(expr->base.type);
8307         if (is_type_scalar(type)) {
8308                 warn_reference_address_as_bool(expr);
8309                 warn_assignment_in_condition(expr);
8310         } else if (is_type_valid(type)) {
8311                 errorf(&expr->base.source_position,
8312                                 "%s must have scalar type", context);
8313         }
8314 }
8315
8316 /**
8317  * Parse a conditional expression, ie. 'expression ? ... : ...'.
8318  *
8319  * @param expression  the conditional expression
8320  */
8321 static expression_t *parse_conditional_expression(expression_t *expression)
8322 {
8323         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
8324
8325         conditional_expression_t *conditional = &result->conditional;
8326         conditional->condition                = expression;
8327
8328         eat('?');
8329         add_anchor_token(':');
8330
8331         /* §6.5.15:2  The first operand shall have scalar type. */
8332         semantic_condition(expression, "condition of conditional operator");
8333
8334         expression_t *true_expression = expression;
8335         bool          gnu_cond = false;
8336         if (GNU_MODE && token.type == ':') {
8337                 gnu_cond = true;
8338         } else {
8339                 true_expression = parse_expression();
8340         }
8341         rem_anchor_token(':');
8342         expect(':', end_error);
8343 end_error:;
8344         expression_t *false_expression =
8345                 parse_sub_expression(c_mode & _CXX ? PREC_ASSIGNMENT : PREC_CONDITIONAL);
8346
8347         type_t *const orig_true_type  = true_expression->base.type;
8348         type_t *const orig_false_type = false_expression->base.type;
8349         type_t *const true_type       = skip_typeref(orig_true_type);
8350         type_t *const false_type      = skip_typeref(orig_false_type);
8351
8352         /* 6.5.15.3 */
8353         type_t *result_type;
8354         if (is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8355                         is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
8356                 /* ISO/IEC 14882:1998(E) §5.16:2 */
8357                 if (true_expression->kind == EXPR_UNARY_THROW) {
8358                         result_type = false_type;
8359                 } else if (false_expression->kind == EXPR_UNARY_THROW) {
8360                         result_type = true_type;
8361                 } else {
8362                         if (warning.other && (
8363                                                 !is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8364                                                 !is_type_atomic(false_type, ATOMIC_TYPE_VOID)
8365                                         )) {
8366                                 warningf(&conditional->base.source_position,
8367                                                 "ISO C forbids conditional expression with only one void side");
8368                         }
8369                         result_type = type_void;
8370                 }
8371         } else if (is_type_arithmetic(true_type)
8372                    && is_type_arithmetic(false_type)) {
8373                 result_type = semantic_arithmetic(true_type, false_type);
8374
8375                 true_expression  = create_implicit_cast(true_expression, result_type);
8376                 false_expression = create_implicit_cast(false_expression, result_type);
8377
8378                 conditional->true_expression  = true_expression;
8379                 conditional->false_expression = false_expression;
8380                 conditional->base.type        = result_type;
8381         } else if (same_compound_type(true_type, false_type)) {
8382                 /* just take 1 of the 2 types */
8383                 result_type = true_type;
8384         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
8385                 type_t *pointer_type;
8386                 type_t *other_type;
8387                 expression_t *other_expression;
8388                 if (is_type_pointer(true_type) &&
8389                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
8390                         pointer_type     = true_type;
8391                         other_type       = false_type;
8392                         other_expression = false_expression;
8393                 } else {
8394                         pointer_type     = false_type;
8395                         other_type       = true_type;
8396                         other_expression = true_expression;
8397                 }
8398
8399                 if (is_null_pointer_constant(other_expression)) {
8400                         result_type = pointer_type;
8401                 } else if (is_type_pointer(other_type)) {
8402                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
8403                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
8404
8405                         type_t *to;
8406                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
8407                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
8408                                 to = type_void;
8409                         } else if (types_compatible(get_unqualified_type(to1),
8410                                                     get_unqualified_type(to2))) {
8411                                 to = to1;
8412                         } else {
8413                                 if (warning.other) {
8414                                         warningf(&conditional->base.source_position,
8415                                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
8416                                                         true_type, false_type);
8417                                 }
8418                                 to = type_void;
8419                         }
8420
8421                         type_t *const type =
8422                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
8423                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
8424                 } else if (is_type_integer(other_type)) {
8425                         if (warning.other) {
8426                                 warningf(&conditional->base.source_position,
8427                                                 "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
8428                         }
8429                         result_type = pointer_type;
8430                 } else {
8431                         if (is_type_valid(other_type)) {
8432                                 type_error_incompatible("while parsing conditional",
8433                                                 &expression->base.source_position, true_type, false_type);
8434                         }
8435                         result_type = type_error_type;
8436                 }
8437         } else {
8438                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
8439                         type_error_incompatible("while parsing conditional",
8440                                                 &conditional->base.source_position, true_type,
8441                                                 false_type);
8442                 }
8443                 result_type = type_error_type;
8444         }
8445
8446         conditional->true_expression
8447                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
8448         conditional->false_expression
8449                 = create_implicit_cast(false_expression, result_type);
8450         conditional->base.type = result_type;
8451         return result;
8452 }
8453
8454 /**
8455  * Parse an extension expression.
8456  */
8457 static expression_t *parse_extension(void)
8458 {
8459         eat(T___extension__);
8460
8461         bool old_gcc_extension   = in_gcc_extension;
8462         in_gcc_extension         = true;
8463         expression_t *expression = parse_sub_expression(PREC_UNARY);
8464         in_gcc_extension         = old_gcc_extension;
8465         return expression;
8466 }
8467
8468 /**
8469  * Parse a __builtin_classify_type() expression.
8470  */
8471 static expression_t *parse_builtin_classify_type(void)
8472 {
8473         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
8474         result->base.type    = type_int;
8475
8476         eat(T___builtin_classify_type);
8477
8478         expect('(', end_error);
8479         add_anchor_token(')');
8480         expression_t *expression = parse_expression();
8481         rem_anchor_token(')');
8482         expect(')', end_error);
8483         result->classify_type.type_expression = expression;
8484
8485         return result;
8486 end_error:
8487         return create_invalid_expression();
8488 }
8489
8490 /**
8491  * Parse a delete expression
8492  * ISO/IEC 14882:1998(E) §5.3.5
8493  */
8494 static expression_t *parse_delete(void)
8495 {
8496         expression_t *const result = allocate_expression_zero(EXPR_UNARY_DELETE);
8497         result->base.type          = type_void;
8498
8499         eat(T_delete);
8500
8501         if (token.type == '[') {
8502                 next_token();
8503                 result->kind = EXPR_UNARY_DELETE_ARRAY;
8504                 expect(']', end_error);
8505 end_error:;
8506         }
8507
8508         expression_t *const value = parse_sub_expression(PREC_CAST);
8509         result->unary.value = value;
8510
8511         type_t *const type = skip_typeref(value->base.type);
8512         if (!is_type_pointer(type)) {
8513                 if (is_type_valid(type)) {
8514                         errorf(&value->base.source_position,
8515                                         "operand of delete must have pointer type");
8516                 }
8517         } else if (warning.other &&
8518                         is_type_atomic(skip_typeref(type->pointer.points_to), ATOMIC_TYPE_VOID)) {
8519                 warningf(&value->base.source_position,
8520                                 "deleting 'void*' is undefined");
8521         }
8522
8523         return result;
8524 }
8525
8526 /**
8527  * Parse a throw expression
8528  * ISO/IEC 14882:1998(E) §15:1
8529  */
8530 static expression_t *parse_throw(void)
8531 {
8532         expression_t *const result = allocate_expression_zero(EXPR_UNARY_THROW);
8533         result->base.type          = type_void;
8534
8535         eat(T_throw);
8536
8537         expression_t *value = NULL;
8538         switch (token.type) {
8539                 EXPRESSION_START {
8540                         value = parse_assignment_expression();
8541                         /* ISO/IEC 14882:1998(E) §15.1:3 */
8542                         type_t *const orig_type = value->base.type;
8543                         type_t *const type      = skip_typeref(orig_type);
8544                         if (is_type_incomplete(type)) {
8545                                 errorf(&value->base.source_position,
8546                                                 "cannot throw object of incomplete type '%T'", orig_type);
8547                         } else if (is_type_pointer(type)) {
8548                                 type_t *const points_to = skip_typeref(type->pointer.points_to);
8549                                 if (is_type_incomplete(points_to) &&
8550                                                 !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8551                                         errorf(&value->base.source_position,
8552                                                         "cannot throw pointer to incomplete type '%T'", orig_type);
8553                                 }
8554                         }
8555                 }
8556
8557                 default:
8558                         break;
8559         }
8560         result->unary.value = value;
8561
8562         return result;
8563 }
8564
8565 static bool check_pointer_arithmetic(const source_position_t *source_position,
8566                                      type_t *pointer_type,
8567                                      type_t *orig_pointer_type)
8568 {
8569         type_t *points_to = pointer_type->pointer.points_to;
8570         points_to = skip_typeref(points_to);
8571
8572         if (is_type_incomplete(points_to)) {
8573                 if (!GNU_MODE || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8574                         errorf(source_position,
8575                                "arithmetic with pointer to incomplete type '%T' not allowed",
8576                                orig_pointer_type);
8577                         return false;
8578                 } else if (warning.pointer_arith) {
8579                         warningf(source_position,
8580                                  "pointer of type '%T' used in arithmetic",
8581                                  orig_pointer_type);
8582                 }
8583         } else if (is_type_function(points_to)) {
8584                 if (!GNU_MODE) {
8585                         errorf(source_position,
8586                                "arithmetic with pointer to function type '%T' not allowed",
8587                                orig_pointer_type);
8588                         return false;
8589                 } else if (warning.pointer_arith) {
8590                         warningf(source_position,
8591                                  "pointer to a function '%T' used in arithmetic",
8592                                  orig_pointer_type);
8593                 }
8594         }
8595         return true;
8596 }
8597
8598 static bool is_lvalue(const expression_t *expression)
8599 {
8600         /* TODO: doesn't seem to be consistent with §6.3.2.1:1 */
8601         switch (expression->kind) {
8602         case EXPR_ARRAY_ACCESS:
8603         case EXPR_COMPOUND_LITERAL:
8604         case EXPR_REFERENCE:
8605         case EXPR_SELECT:
8606         case EXPR_UNARY_DEREFERENCE:
8607                 return true;
8608
8609         default: {
8610           type_t *type = skip_typeref(expression->base.type);
8611           return
8612                 /* ISO/IEC 14882:1998(E) §3.10:3 */
8613                 is_type_reference(type) ||
8614                 /* Claim it is an lvalue, if the type is invalid.  There was a parse
8615                  * error before, which maybe prevented properly recognizing it as
8616                  * lvalue. */
8617                 !is_type_valid(type);
8618         }
8619         }
8620 }
8621
8622 static void semantic_incdec(unary_expression_t *expression)
8623 {
8624         type_t *const orig_type = expression->value->base.type;
8625         type_t *const type      = skip_typeref(orig_type);
8626         if (is_type_pointer(type)) {
8627                 if (!check_pointer_arithmetic(&expression->base.source_position,
8628                                               type, orig_type)) {
8629                         return;
8630                 }
8631         } else if (!is_type_real(type) && is_type_valid(type)) {
8632                 /* TODO: improve error message */
8633                 errorf(&expression->base.source_position,
8634                        "operation needs an arithmetic or pointer type");
8635                 return;
8636         }
8637         if (!is_lvalue(expression->value)) {
8638                 /* TODO: improve error message */
8639                 errorf(&expression->base.source_position, "lvalue required as operand");
8640         }
8641         expression->base.type = orig_type;
8642 }
8643
8644 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
8645 {
8646         type_t *const orig_type = expression->value->base.type;
8647         type_t *const type      = skip_typeref(orig_type);
8648         if (!is_type_arithmetic(type)) {
8649                 if (is_type_valid(type)) {
8650                         /* TODO: improve error message */
8651                         errorf(&expression->base.source_position,
8652                                 "operation needs an arithmetic type");
8653                 }
8654                 return;
8655         }
8656
8657         expression->base.type = orig_type;
8658 }
8659
8660 static void semantic_unexpr_plus(unary_expression_t *expression)
8661 {
8662         semantic_unexpr_arithmetic(expression);
8663         if (warning.traditional)
8664                 warningf(&expression->base.source_position,
8665                         "traditional C rejects the unary plus operator");
8666 }
8667
8668 static void semantic_not(unary_expression_t *expression)
8669 {
8670         /* §6.5.3.3:1  The operand [...] of the ! operator, scalar type. */
8671         semantic_condition(expression->value, "operand of !");
8672         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8673 }
8674
8675 static void semantic_unexpr_integer(unary_expression_t *expression)
8676 {
8677         type_t *const orig_type = expression->value->base.type;
8678         type_t *const type      = skip_typeref(orig_type);
8679         if (!is_type_integer(type)) {
8680                 if (is_type_valid(type)) {
8681                         errorf(&expression->base.source_position,
8682                                "operand of ~ must be of integer type");
8683                 }
8684                 return;
8685         }
8686
8687         expression->base.type = orig_type;
8688 }
8689
8690 static void semantic_dereference(unary_expression_t *expression)
8691 {
8692         type_t *const orig_type = expression->value->base.type;
8693         type_t *const type      = skip_typeref(orig_type);
8694         if (!is_type_pointer(type)) {
8695                 if (is_type_valid(type)) {
8696                         errorf(&expression->base.source_position,
8697                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
8698                 }
8699                 return;
8700         }
8701
8702         type_t *result_type   = type->pointer.points_to;
8703         result_type           = automatic_type_conversion(result_type);
8704         expression->base.type = result_type;
8705 }
8706
8707 /**
8708  * Record that an address is taken (expression represents an lvalue).
8709  *
8710  * @param expression       the expression
8711  * @param may_be_register  if true, the expression might be an register
8712  */
8713 static void set_address_taken(expression_t *expression, bool may_be_register)
8714 {
8715         if (expression->kind != EXPR_REFERENCE)
8716                 return;
8717
8718         entity_t *const entity = expression->reference.entity;
8719
8720         if (entity->kind != ENTITY_VARIABLE && entity->kind != ENTITY_PARAMETER)
8721                 return;
8722
8723         if (entity->declaration.storage_class == STORAGE_CLASS_REGISTER
8724                         && !may_be_register) {
8725                 errorf(&expression->base.source_position,
8726                                 "address of register %s '%Y' requested",
8727                                 get_entity_kind_name(entity->kind),     entity->base.symbol);
8728         }
8729
8730         if (entity->kind == ENTITY_VARIABLE) {
8731                 entity->variable.address_taken = true;
8732         } else {
8733                 assert(entity->kind == ENTITY_PARAMETER);
8734                 entity->parameter.address_taken = true;
8735         }
8736 }
8737
8738 /**
8739  * Check the semantic of the address taken expression.
8740  */
8741 static void semantic_take_addr(unary_expression_t *expression)
8742 {
8743         expression_t *value = expression->value;
8744         value->base.type    = revert_automatic_type_conversion(value);
8745
8746         type_t *orig_type = value->base.type;
8747         type_t *type      = skip_typeref(orig_type);
8748         if (!is_type_valid(type))
8749                 return;
8750
8751         /* §6.5.3.2 */
8752         if (!is_lvalue(value)) {
8753                 errorf(&expression->base.source_position, "'&' requires an lvalue");
8754         }
8755         if (type->kind == TYPE_BITFIELD) {
8756                 errorf(&expression->base.source_position,
8757                        "'&' not allowed on object with bitfield type '%T'",
8758                        type);
8759         }
8760
8761         set_address_taken(value, false);
8762
8763         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
8764 }
8765
8766 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc) \
8767 static expression_t *parse_##unexpression_type(void)                         \
8768 {                                                                            \
8769         expression_t *unary_expression                                           \
8770                 = allocate_expression_zero(unexpression_type);                       \
8771         eat(token_type);                                                         \
8772         unary_expression->unary.value = parse_sub_expression(PREC_UNARY);        \
8773                                                                                  \
8774         sfunc(&unary_expression->unary);                                         \
8775                                                                                  \
8776         return unary_expression;                                                 \
8777 }
8778
8779 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
8780                                semantic_unexpr_arithmetic)
8781 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
8782                                semantic_unexpr_plus)
8783 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
8784                                semantic_not)
8785 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
8786                                semantic_dereference)
8787 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
8788                                semantic_take_addr)
8789 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
8790                                semantic_unexpr_integer)
8791 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
8792                                semantic_incdec)
8793 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
8794                                semantic_incdec)
8795
8796 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
8797                                                sfunc)                         \
8798 static expression_t *parse_##unexpression_type(expression_t *left)            \
8799 {                                                                             \
8800         expression_t *unary_expression                                            \
8801                 = allocate_expression_zero(unexpression_type);                        \
8802         eat(token_type);                                                          \
8803         unary_expression->unary.value = left;                                     \
8804                                                                                   \
8805         sfunc(&unary_expression->unary);                                          \
8806                                                                               \
8807         return unary_expression;                                                  \
8808 }
8809
8810 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
8811                                        EXPR_UNARY_POSTFIX_INCREMENT,
8812                                        semantic_incdec)
8813 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
8814                                        EXPR_UNARY_POSTFIX_DECREMENT,
8815                                        semantic_incdec)
8816
8817 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
8818 {
8819         /* TODO: handle complex + imaginary types */
8820
8821         type_left  = get_unqualified_type(type_left);
8822         type_right = get_unqualified_type(type_right);
8823
8824         /* §6.3.1.8 Usual arithmetic conversions */
8825         if (type_left == type_long_double || type_right == type_long_double) {
8826                 return type_long_double;
8827         } else if (type_left == type_double || type_right == type_double) {
8828                 return type_double;
8829         } else if (type_left == type_float || type_right == type_float) {
8830                 return type_float;
8831         }
8832
8833         type_left  = promote_integer(type_left);
8834         type_right = promote_integer(type_right);
8835
8836         if (type_left == type_right)
8837                 return type_left;
8838
8839         bool const signed_left  = is_type_signed(type_left);
8840         bool const signed_right = is_type_signed(type_right);
8841         int const  rank_left    = get_rank(type_left);
8842         int const  rank_right   = get_rank(type_right);
8843
8844         if (signed_left == signed_right)
8845                 return rank_left >= rank_right ? type_left : type_right;
8846
8847         int     s_rank;
8848         int     u_rank;
8849         type_t *s_type;
8850         type_t *u_type;
8851         if (signed_left) {
8852                 s_rank = rank_left;
8853                 s_type = type_left;
8854                 u_rank = rank_right;
8855                 u_type = type_right;
8856         } else {
8857                 s_rank = rank_right;
8858                 s_type = type_right;
8859                 u_rank = rank_left;
8860                 u_type = type_left;
8861         }
8862
8863         if (u_rank >= s_rank)
8864                 return u_type;
8865
8866         /* casting rank to atomic_type_kind is a bit hacky, but makes things
8867          * easier here... */
8868         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
8869                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
8870                 return s_type;
8871
8872         switch (s_rank) {
8873                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
8874                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
8875                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
8876
8877                 default: panic("invalid atomic type");
8878         }
8879 }
8880
8881 /**
8882  * Check the semantic restrictions for a binary expression.
8883  */
8884 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
8885 {
8886         expression_t *const left            = expression->left;
8887         expression_t *const right           = expression->right;
8888         type_t       *const orig_type_left  = left->base.type;
8889         type_t       *const orig_type_right = right->base.type;
8890         type_t       *const type_left       = skip_typeref(orig_type_left);
8891         type_t       *const type_right      = skip_typeref(orig_type_right);
8892
8893         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8894                 /* TODO: improve error message */
8895                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8896                         errorf(&expression->base.source_position,
8897                                "operation needs arithmetic types");
8898                 }
8899                 return;
8900         }
8901
8902         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8903         expression->left      = create_implicit_cast(left, arithmetic_type);
8904         expression->right     = create_implicit_cast(right, arithmetic_type);
8905         expression->base.type = arithmetic_type;
8906 }
8907
8908 static void warn_div_by_zero(binary_expression_t const *const expression)
8909 {
8910         if (!warning.div_by_zero ||
8911             !is_type_integer(expression->base.type))
8912                 return;
8913
8914         expression_t const *const right = expression->right;
8915         /* The type of the right operand can be different for /= */
8916         if (is_type_integer(right->base.type) &&
8917             is_constant_expression(right)     &&
8918             fold_constant(right) == 0) {
8919                 warningf(&expression->base.source_position, "division by zero");
8920         }
8921 }
8922
8923 /**
8924  * Check the semantic restrictions for a div/mod expression.
8925  */
8926 static void semantic_divmod_arithmetic(binary_expression_t *expression)
8927 {
8928         semantic_binexpr_arithmetic(expression);
8929         warn_div_by_zero(expression);
8930 }
8931
8932 static void warn_addsub_in_shift(const expression_t *const expr)
8933 {
8934         if (expr->base.parenthesized)
8935                 return;
8936
8937         char op;
8938         switch (expr->kind) {
8939                 case EXPR_BINARY_ADD: op = '+'; break;
8940                 case EXPR_BINARY_SUB: op = '-'; break;
8941                 default:              return;
8942         }
8943
8944         warningf(&expr->base.source_position,
8945                         "suggest parentheses around '%c' inside shift", op);
8946 }
8947
8948 static void semantic_shift_op(binary_expression_t *expression)
8949 {
8950         expression_t *const left            = expression->left;
8951         expression_t *const right           = expression->right;
8952         type_t       *const orig_type_left  = left->base.type;
8953         type_t       *const orig_type_right = right->base.type;
8954         type_t       *      type_left       = skip_typeref(orig_type_left);
8955         type_t       *      type_right      = skip_typeref(orig_type_right);
8956
8957         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8958                 /* TODO: improve error message */
8959                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8960                         errorf(&expression->base.source_position,
8961                                "operands of shift operation must have integer types");
8962                 }
8963                 return;
8964         }
8965
8966         if (warning.parentheses) {
8967                 warn_addsub_in_shift(left);
8968                 warn_addsub_in_shift(right);
8969         }
8970
8971         type_left  = promote_integer(type_left);
8972         type_right = promote_integer(type_right);
8973
8974         expression->left      = create_implicit_cast(left, type_left);
8975         expression->right     = create_implicit_cast(right, type_right);
8976         expression->base.type = type_left;
8977 }
8978
8979 static void semantic_add(binary_expression_t *expression)
8980 {
8981         expression_t *const left            = expression->left;
8982         expression_t *const right           = expression->right;
8983         type_t       *const orig_type_left  = left->base.type;
8984         type_t       *const orig_type_right = right->base.type;
8985         type_t       *const type_left       = skip_typeref(orig_type_left);
8986         type_t       *const type_right      = skip_typeref(orig_type_right);
8987
8988         /* §6.5.6 */
8989         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8990                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8991                 expression->left  = create_implicit_cast(left, arithmetic_type);
8992                 expression->right = create_implicit_cast(right, arithmetic_type);
8993                 expression->base.type = arithmetic_type;
8994         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8995                 check_pointer_arithmetic(&expression->base.source_position,
8996                                          type_left, orig_type_left);
8997                 expression->base.type = type_left;
8998         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
8999                 check_pointer_arithmetic(&expression->base.source_position,
9000                                          type_right, orig_type_right);
9001                 expression->base.type = type_right;
9002         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9003                 errorf(&expression->base.source_position,
9004                        "invalid operands to binary + ('%T', '%T')",
9005                        orig_type_left, orig_type_right);
9006         }
9007 }
9008
9009 static void semantic_sub(binary_expression_t *expression)
9010 {
9011         expression_t            *const left            = expression->left;
9012         expression_t            *const right           = expression->right;
9013         type_t                  *const orig_type_left  = left->base.type;
9014         type_t                  *const orig_type_right = right->base.type;
9015         type_t                  *const type_left       = skip_typeref(orig_type_left);
9016         type_t                  *const type_right      = skip_typeref(orig_type_right);
9017         source_position_t const *const pos             = &expression->base.source_position;
9018
9019         /* §5.6.5 */
9020         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
9021                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
9022                 expression->left        = create_implicit_cast(left, arithmetic_type);
9023                 expression->right       = create_implicit_cast(right, arithmetic_type);
9024                 expression->base.type =  arithmetic_type;
9025         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
9026                 check_pointer_arithmetic(&expression->base.source_position,
9027                                          type_left, orig_type_left);
9028                 expression->base.type = type_left;
9029         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
9030                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
9031                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
9032                 if (!types_compatible(unqual_left, unqual_right)) {
9033                         errorf(pos,
9034                                "subtracting pointers to incompatible types '%T' and '%T'",
9035                                orig_type_left, orig_type_right);
9036                 } else if (!is_type_object(unqual_left)) {
9037                         if (!is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
9038                                 errorf(pos, "subtracting pointers to non-object types '%T'",
9039                                        orig_type_left);
9040                         } else if (warning.other) {
9041                                 warningf(pos, "subtracting pointers to void");
9042                         }
9043                 }
9044                 expression->base.type = type_ptrdiff_t;
9045         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9046                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
9047                        orig_type_left, orig_type_right);
9048         }
9049 }
9050
9051 static void warn_string_literal_address(expression_t const* expr)
9052 {
9053         while (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
9054                 expr = expr->unary.value;
9055                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
9056                         return;
9057                 expr = expr->unary.value;
9058         }
9059
9060         if (expr->kind == EXPR_STRING_LITERAL ||
9061             expr->kind == EXPR_WIDE_STRING_LITERAL) {
9062                 warningf(&expr->base.source_position,
9063                         "comparison with string literal results in unspecified behaviour");
9064         }
9065 }
9066
9067 static void warn_comparison_in_comparison(const expression_t *const expr)
9068 {
9069         if (expr->base.parenthesized)
9070                 return;
9071         switch (expr->base.kind) {
9072                 case EXPR_BINARY_LESS:
9073                 case EXPR_BINARY_GREATER:
9074                 case EXPR_BINARY_LESSEQUAL:
9075                 case EXPR_BINARY_GREATEREQUAL:
9076                 case EXPR_BINARY_NOTEQUAL:
9077                 case EXPR_BINARY_EQUAL:
9078                         warningf(&expr->base.source_position,
9079                                         "comparisons like 'x <= y < z' do not have their mathematical meaning");
9080                         break;
9081                 default:
9082                         break;
9083         }
9084 }
9085
9086 static bool maybe_negative(expression_t const *const expr)
9087 {
9088         return
9089                 !is_constant_expression(expr) ||
9090                 fold_constant(expr) < 0;
9091 }
9092
9093 /**
9094  * Check the semantics of comparison expressions.
9095  *
9096  * @param expression   The expression to check.
9097  */
9098 static void semantic_comparison(binary_expression_t *expression)
9099 {
9100         expression_t *left  = expression->left;
9101         expression_t *right = expression->right;
9102
9103         if (warning.address) {
9104                 warn_string_literal_address(left);
9105                 warn_string_literal_address(right);
9106
9107                 expression_t const* const func_left = get_reference_address(left);
9108                 if (func_left != NULL && is_null_pointer_constant(right)) {
9109                         warningf(&expression->base.source_position,
9110                                  "the address of '%Y' will never be NULL",
9111                                  func_left->reference.entity->base.symbol);
9112                 }
9113
9114                 expression_t const* const func_right = get_reference_address(right);
9115                 if (func_right != NULL && is_null_pointer_constant(right)) {
9116                         warningf(&expression->base.source_position,
9117                                  "the address of '%Y' will never be NULL",
9118                                  func_right->reference.entity->base.symbol);
9119                 }
9120         }
9121
9122         if (warning.parentheses) {
9123                 warn_comparison_in_comparison(left);
9124                 warn_comparison_in_comparison(right);
9125         }
9126
9127         type_t *orig_type_left  = left->base.type;
9128         type_t *orig_type_right = right->base.type;
9129         type_t *type_left       = skip_typeref(orig_type_left);
9130         type_t *type_right      = skip_typeref(orig_type_right);
9131
9132         /* TODO non-arithmetic types */
9133         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
9134                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
9135
9136                 /* test for signed vs unsigned compares */
9137                 if (warning.sign_compare && is_type_integer(arithmetic_type)) {
9138                         bool const signed_left  = is_type_signed(type_left);
9139                         bool const signed_right = is_type_signed(type_right);
9140                         if (signed_left != signed_right) {
9141                                 /* FIXME long long needs better const folding magic */
9142                                 /* TODO check whether constant value can be represented by other type */
9143                                 if ((signed_left  && maybe_negative(left)) ||
9144                                                 (signed_right && maybe_negative(right))) {
9145                                         warningf(&expression->base.source_position,
9146                                                         "comparison between signed and unsigned");
9147                                 }
9148                         }
9149                 }
9150
9151                 expression->left        = create_implicit_cast(left, arithmetic_type);
9152                 expression->right       = create_implicit_cast(right, arithmetic_type);
9153                 expression->base.type   = arithmetic_type;
9154                 if (warning.float_equal &&
9155                     (expression->base.kind == EXPR_BINARY_EQUAL ||
9156                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
9157                     is_type_float(arithmetic_type)) {
9158                         warningf(&expression->base.source_position,
9159                                  "comparing floating point with == or != is unsafe");
9160                 }
9161         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
9162                 /* TODO check compatibility */
9163         } else if (is_type_pointer(type_left)) {
9164                 expression->right = create_implicit_cast(right, type_left);
9165         } else if (is_type_pointer(type_right)) {
9166                 expression->left = create_implicit_cast(left, type_right);
9167         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9168                 type_error_incompatible("invalid operands in comparison",
9169                                         &expression->base.source_position,
9170                                         type_left, type_right);
9171         }
9172         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9173 }
9174
9175 /**
9176  * Checks if a compound type has constant fields.
9177  */
9178 static bool has_const_fields(const compound_type_t *type)
9179 {
9180         compound_t *compound = type->compound;
9181         entity_t   *entry    = compound->members.entities;
9182
9183         for (; entry != NULL; entry = entry->base.next) {
9184                 if (!is_declaration(entry))
9185                         continue;
9186
9187                 const type_t *decl_type = skip_typeref(entry->declaration.type);
9188                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
9189                         return true;
9190         }
9191
9192         return false;
9193 }
9194
9195 static bool is_valid_assignment_lhs(expression_t const* const left)
9196 {
9197         type_t *const orig_type_left = revert_automatic_type_conversion(left);
9198         type_t *const type_left      = skip_typeref(orig_type_left);
9199
9200         if (!is_lvalue(left)) {
9201                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
9202                        left);
9203                 return false;
9204         }
9205
9206         if (left->kind == EXPR_REFERENCE
9207                         && left->reference.entity->kind == ENTITY_FUNCTION) {
9208                 errorf(HERE, "cannot assign to function '%E'", left);
9209                 return false;
9210         }
9211
9212         if (is_type_array(type_left)) {
9213                 errorf(HERE, "cannot assign to array '%E'", left);
9214                 return false;
9215         }
9216         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
9217                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
9218                        orig_type_left);
9219                 return false;
9220         }
9221         if (is_type_incomplete(type_left)) {
9222                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
9223                        left, orig_type_left);
9224                 return false;
9225         }
9226         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
9227                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
9228                        left, orig_type_left);
9229                 return false;
9230         }
9231
9232         return true;
9233 }
9234
9235 static void semantic_arithmetic_assign(binary_expression_t *expression)
9236 {
9237         expression_t *left            = expression->left;
9238         expression_t *right           = expression->right;
9239         type_t       *orig_type_left  = left->base.type;
9240         type_t       *orig_type_right = right->base.type;
9241
9242         if (!is_valid_assignment_lhs(left))
9243                 return;
9244
9245         type_t *type_left  = skip_typeref(orig_type_left);
9246         type_t *type_right = skip_typeref(orig_type_right);
9247
9248         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
9249                 /* TODO: improve error message */
9250                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
9251                         errorf(&expression->base.source_position,
9252                                "operation needs arithmetic types");
9253                 }
9254                 return;
9255         }
9256
9257         /* combined instructions are tricky. We can't create an implicit cast on
9258          * the left side, because we need the uncasted form for the store.
9259          * The ast2firm pass has to know that left_type must be right_type
9260          * for the arithmetic operation and create a cast by itself */
9261         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
9262         expression->right       = create_implicit_cast(right, arithmetic_type);
9263         expression->base.type   = type_left;
9264 }
9265
9266 static void semantic_divmod_assign(binary_expression_t *expression)
9267 {
9268         semantic_arithmetic_assign(expression);
9269         warn_div_by_zero(expression);
9270 }
9271
9272 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
9273 {
9274         expression_t *const left            = expression->left;
9275         expression_t *const right           = expression->right;
9276         type_t       *const orig_type_left  = left->base.type;
9277         type_t       *const orig_type_right = right->base.type;
9278         type_t       *const type_left       = skip_typeref(orig_type_left);
9279         type_t       *const type_right      = skip_typeref(orig_type_right);
9280
9281         if (!is_valid_assignment_lhs(left))
9282                 return;
9283
9284         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
9285                 /* combined instructions are tricky. We can't create an implicit cast on
9286                  * the left side, because we need the uncasted form for the store.
9287                  * The ast2firm pass has to know that left_type must be right_type
9288                  * for the arithmetic operation and create a cast by itself */
9289                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
9290                 expression->right     = create_implicit_cast(right, arithmetic_type);
9291                 expression->base.type = type_left;
9292         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
9293                 check_pointer_arithmetic(&expression->base.source_position,
9294                                          type_left, orig_type_left);
9295                 expression->base.type = type_left;
9296         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9297                 errorf(&expression->base.source_position,
9298                        "incompatible types '%T' and '%T' in assignment",
9299                        orig_type_left, orig_type_right);
9300         }
9301 }
9302
9303 static void warn_logical_and_within_or(const expression_t *const expr)
9304 {
9305         if (expr->base.kind != EXPR_BINARY_LOGICAL_AND)
9306                 return;
9307         if (expr->base.parenthesized)
9308                 return;
9309         warningf(&expr->base.source_position,
9310                         "suggest parentheses around && within ||");
9311 }
9312
9313 /**
9314  * Check the semantic restrictions of a logical expression.
9315  */
9316 static void semantic_logical_op(binary_expression_t *expression)
9317 {
9318         /* §6.5.13:2  Each of the operands shall have scalar type.
9319          * §6.5.14:2  Each of the operands shall have scalar type. */
9320         semantic_condition(expression->left,   "left operand of logical operator");
9321         semantic_condition(expression->right, "right operand of logical operator");
9322         if (expression->base.kind == EXPR_BINARY_LOGICAL_OR &&
9323                         warning.parentheses) {
9324                 warn_logical_and_within_or(expression->left);
9325                 warn_logical_and_within_or(expression->right);
9326         }
9327         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9328 }
9329
9330 /**
9331  * Check the semantic restrictions of a binary assign expression.
9332  */
9333 static void semantic_binexpr_assign(binary_expression_t *expression)
9334 {
9335         expression_t *left           = expression->left;
9336         type_t       *orig_type_left = left->base.type;
9337
9338         if (!is_valid_assignment_lhs(left))
9339                 return;
9340
9341         assign_error_t error = semantic_assign(orig_type_left, expression->right);
9342         report_assign_error(error, orig_type_left, expression->right,
9343                         "assignment", &left->base.source_position);
9344         expression->right = create_implicit_cast(expression->right, orig_type_left);
9345         expression->base.type = orig_type_left;
9346 }
9347
9348 /**
9349  * Determine if the outermost operation (or parts thereof) of the given
9350  * expression has no effect in order to generate a warning about this fact.
9351  * Therefore in some cases this only examines some of the operands of the
9352  * expression (see comments in the function and examples below).
9353  * Examples:
9354  *   f() + 23;    // warning, because + has no effect
9355  *   x || f();    // no warning, because x controls execution of f()
9356  *   x ? y : f(); // warning, because y has no effect
9357  *   (void)x;     // no warning to be able to suppress the warning
9358  * This function can NOT be used for an "expression has definitely no effect"-
9359  * analysis. */
9360 static bool expression_has_effect(const expression_t *const expr)
9361 {
9362         switch (expr->kind) {
9363                 case EXPR_UNKNOWN:                    break;
9364                 case EXPR_INVALID:                    return true; /* do NOT warn */
9365                 case EXPR_REFERENCE:                  return false;
9366                 case EXPR_REFERENCE_ENUM_VALUE:       return false;
9367                 /* suppress the warning for microsoft __noop operations */
9368                 case EXPR_CONST:                      return expr->conste.is_ms_noop;
9369                 case EXPR_CHARACTER_CONSTANT:         return false;
9370                 case EXPR_WIDE_CHARACTER_CONSTANT:    return false;
9371                 case EXPR_STRING_LITERAL:             return false;
9372                 case EXPR_WIDE_STRING_LITERAL:        return false;
9373                 case EXPR_LABEL_ADDRESS:              return false;
9374
9375                 case EXPR_CALL: {
9376                         const call_expression_t *const call = &expr->call;
9377                         if (call->function->kind != EXPR_REFERENCE)
9378                                 return true;
9379
9380                         switch (call->function->reference.entity->function.btk) {
9381                                 /* FIXME: which builtins have no effect? */
9382                                 default:                      return true;
9383                         }
9384                 }
9385
9386                 /* Generate the warning if either the left or right hand side of a
9387                  * conditional expression has no effect */
9388                 case EXPR_CONDITIONAL: {
9389                         conditional_expression_t const *const cond = &expr->conditional;
9390                         expression_t             const *const t    = cond->true_expression;
9391                         return
9392                                 (t == NULL || expression_has_effect(t)) &&
9393                                 expression_has_effect(cond->false_expression);
9394                 }
9395
9396                 case EXPR_SELECT:                     return false;
9397                 case EXPR_ARRAY_ACCESS:               return false;
9398                 case EXPR_SIZEOF:                     return false;
9399                 case EXPR_CLASSIFY_TYPE:              return false;
9400                 case EXPR_ALIGNOF:                    return false;
9401
9402                 case EXPR_FUNCNAME:                   return false;
9403                 case EXPR_BUILTIN_CONSTANT_P:         return false;
9404                 case EXPR_BUILTIN_TYPES_COMPATIBLE_P: return false;
9405                 case EXPR_OFFSETOF:                   return false;
9406                 case EXPR_VA_START:                   return true;
9407                 case EXPR_VA_ARG:                     return true;
9408                 case EXPR_VA_COPY:                    return true;
9409                 case EXPR_STATEMENT:                  return true; // TODO
9410                 case EXPR_COMPOUND_LITERAL:           return false;
9411
9412                 case EXPR_UNARY_NEGATE:               return false;
9413                 case EXPR_UNARY_PLUS:                 return false;
9414                 case EXPR_UNARY_BITWISE_NEGATE:       return false;
9415                 case EXPR_UNARY_NOT:                  return false;
9416                 case EXPR_UNARY_DEREFERENCE:          return false;
9417                 case EXPR_UNARY_TAKE_ADDRESS:         return false;
9418                 case EXPR_UNARY_POSTFIX_INCREMENT:    return true;
9419                 case EXPR_UNARY_POSTFIX_DECREMENT:    return true;
9420                 case EXPR_UNARY_PREFIX_INCREMENT:     return true;
9421                 case EXPR_UNARY_PREFIX_DECREMENT:     return true;
9422
9423                 /* Treat void casts as if they have an effect in order to being able to
9424                  * suppress the warning */
9425                 case EXPR_UNARY_CAST: {
9426                         type_t *const type = skip_typeref(expr->base.type);
9427                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
9428                 }
9429
9430                 case EXPR_UNARY_CAST_IMPLICIT:        return true;
9431                 case EXPR_UNARY_ASSUME:               return true;
9432                 case EXPR_UNARY_DELETE:               return true;
9433                 case EXPR_UNARY_DELETE_ARRAY:         return true;
9434                 case EXPR_UNARY_THROW:                return true;
9435
9436                 case EXPR_BINARY_ADD:                 return false;
9437                 case EXPR_BINARY_SUB:                 return false;
9438                 case EXPR_BINARY_MUL:                 return false;
9439                 case EXPR_BINARY_DIV:                 return false;
9440                 case EXPR_BINARY_MOD:                 return false;
9441                 case EXPR_BINARY_EQUAL:               return false;
9442                 case EXPR_BINARY_NOTEQUAL:            return false;
9443                 case EXPR_BINARY_LESS:                return false;
9444                 case EXPR_BINARY_LESSEQUAL:           return false;
9445                 case EXPR_BINARY_GREATER:             return false;
9446                 case EXPR_BINARY_GREATEREQUAL:        return false;
9447                 case EXPR_BINARY_BITWISE_AND:         return false;
9448                 case EXPR_BINARY_BITWISE_OR:          return false;
9449                 case EXPR_BINARY_BITWISE_XOR:         return false;
9450                 case EXPR_BINARY_SHIFTLEFT:           return false;
9451                 case EXPR_BINARY_SHIFTRIGHT:          return false;
9452                 case EXPR_BINARY_ASSIGN:              return true;
9453                 case EXPR_BINARY_MUL_ASSIGN:          return true;
9454                 case EXPR_BINARY_DIV_ASSIGN:          return true;
9455                 case EXPR_BINARY_MOD_ASSIGN:          return true;
9456                 case EXPR_BINARY_ADD_ASSIGN:          return true;
9457                 case EXPR_BINARY_SUB_ASSIGN:          return true;
9458                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:    return true;
9459                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:   return true;
9460                 case EXPR_BINARY_BITWISE_AND_ASSIGN:  return true;
9461                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:  return true;
9462                 case EXPR_BINARY_BITWISE_OR_ASSIGN:   return true;
9463
9464                 /* Only examine the right hand side of && and ||, because the left hand
9465                  * side already has the effect of controlling the execution of the right
9466                  * hand side */
9467                 case EXPR_BINARY_LOGICAL_AND:
9468                 case EXPR_BINARY_LOGICAL_OR:
9469                 /* Only examine the right hand side of a comma expression, because the left
9470                  * hand side has a separate warning */
9471                 case EXPR_BINARY_COMMA:
9472                         return expression_has_effect(expr->binary.right);
9473
9474                 case EXPR_BINARY_ISGREATER:           return false;
9475                 case EXPR_BINARY_ISGREATEREQUAL:      return false;
9476                 case EXPR_BINARY_ISLESS:              return false;
9477                 case EXPR_BINARY_ISLESSEQUAL:         return false;
9478                 case EXPR_BINARY_ISLESSGREATER:       return false;
9479                 case EXPR_BINARY_ISUNORDERED:         return false;
9480         }
9481
9482         internal_errorf(HERE, "unexpected expression");
9483 }
9484
9485 static void semantic_comma(binary_expression_t *expression)
9486 {
9487         if (warning.unused_value) {
9488                 const expression_t *const left = expression->left;
9489                 if (!expression_has_effect(left)) {
9490                         warningf(&left->base.source_position,
9491                                  "left-hand operand of comma expression has no effect");
9492                 }
9493         }
9494         expression->base.type = expression->right->base.type;
9495 }
9496
9497 /**
9498  * @param prec_r precedence of the right operand
9499  */
9500 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, prec_r, sfunc) \
9501 static expression_t *parse_##binexpression_type(expression_t *left)          \
9502 {                                                                            \
9503         expression_t *binexpr = allocate_expression_zero(binexpression_type);    \
9504         binexpr->binary.left  = left;                                            \
9505         eat(token_type);                                                         \
9506                                                                              \
9507         expression_t *right = parse_sub_expression(prec_r);                      \
9508                                                                              \
9509         binexpr->binary.right = right;                                           \
9510         sfunc(&binexpr->binary);                                                 \
9511                                                                              \
9512         return binexpr;                                                          \
9513 }
9514
9515 CREATE_BINEXPR_PARSER('*',                    EXPR_BINARY_MUL,                PREC_CAST,           semantic_binexpr_arithmetic)
9516 CREATE_BINEXPR_PARSER('/',                    EXPR_BINARY_DIV,                PREC_CAST,           semantic_divmod_arithmetic)
9517 CREATE_BINEXPR_PARSER('%',                    EXPR_BINARY_MOD,                PREC_CAST,           semantic_divmod_arithmetic)
9518 CREATE_BINEXPR_PARSER('+',                    EXPR_BINARY_ADD,                PREC_MULTIPLICATIVE, semantic_add)
9519 CREATE_BINEXPR_PARSER('-',                    EXPR_BINARY_SUB,                PREC_MULTIPLICATIVE, semantic_sub)
9520 CREATE_BINEXPR_PARSER(T_LESSLESS,             EXPR_BINARY_SHIFTLEFT,          PREC_ADDITIVE,       semantic_shift_op)
9521 CREATE_BINEXPR_PARSER(T_GREATERGREATER,       EXPR_BINARY_SHIFTRIGHT,         PREC_ADDITIVE,       semantic_shift_op)
9522 CREATE_BINEXPR_PARSER('<',                    EXPR_BINARY_LESS,               PREC_SHIFT,          semantic_comparison)
9523 CREATE_BINEXPR_PARSER('>',                    EXPR_BINARY_GREATER,            PREC_SHIFT,          semantic_comparison)
9524 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,          PREC_SHIFT,          semantic_comparison)
9525 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,       PREC_SHIFT,          semantic_comparison)
9526 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,           PREC_RELATIONAL,     semantic_comparison)
9527 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,              PREC_RELATIONAL,     semantic_comparison)
9528 CREATE_BINEXPR_PARSER('&',                    EXPR_BINARY_BITWISE_AND,        PREC_EQUALITY,       semantic_binexpr_arithmetic)
9529 CREATE_BINEXPR_PARSER('^',                    EXPR_BINARY_BITWISE_XOR,        PREC_AND,            semantic_binexpr_arithmetic)
9530 CREATE_BINEXPR_PARSER('|',                    EXPR_BINARY_BITWISE_OR,         PREC_XOR,            semantic_binexpr_arithmetic)
9531 CREATE_BINEXPR_PARSER(T_ANDAND,               EXPR_BINARY_LOGICAL_AND,        PREC_OR,             semantic_logical_op)
9532 CREATE_BINEXPR_PARSER(T_PIPEPIPE,             EXPR_BINARY_LOGICAL_OR,         PREC_LOGICAL_AND,    semantic_logical_op)
9533 CREATE_BINEXPR_PARSER('=',                    EXPR_BINARY_ASSIGN,             PREC_ASSIGNMENT,     semantic_binexpr_assign)
9534 CREATE_BINEXPR_PARSER(T_PLUSEQUAL,            EXPR_BINARY_ADD_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9535 CREATE_BINEXPR_PARSER(T_MINUSEQUAL,           EXPR_BINARY_SUB_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9536 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL,        EXPR_BINARY_MUL_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9537 CREATE_BINEXPR_PARSER(T_SLASHEQUAL,           EXPR_BINARY_DIV_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9538 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL,         EXPR_BINARY_MOD_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9539 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL,        EXPR_BINARY_SHIFTLEFT_ASSIGN,   PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9540 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL,  EXPR_BINARY_SHIFTRIGHT_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9541 CREATE_BINEXPR_PARSER(T_ANDEQUAL,             EXPR_BINARY_BITWISE_AND_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9542 CREATE_BINEXPR_PARSER(T_PIPEEQUAL,            EXPR_BINARY_BITWISE_OR_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9543 CREATE_BINEXPR_PARSER(T_CARETEQUAL,           EXPR_BINARY_BITWISE_XOR_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9544 CREATE_BINEXPR_PARSER(',',                    EXPR_BINARY_COMMA,              PREC_ASSIGNMENT,     semantic_comma)
9545
9546
9547 static expression_t *parse_sub_expression(precedence_t precedence)
9548 {
9549         if (token.type < 0) {
9550                 return expected_expression_error();
9551         }
9552
9553         expression_parser_function_t *parser
9554                 = &expression_parsers[token.type];
9555         source_position_t             source_position = token.source_position;
9556         expression_t                 *left;
9557
9558         if (parser->parser != NULL) {
9559                 left = parser->parser();
9560         } else {
9561                 left = parse_primary_expression();
9562         }
9563         assert(left != NULL);
9564         left->base.source_position = source_position;
9565
9566         while (true) {
9567                 if (token.type < 0) {
9568                         return expected_expression_error();
9569                 }
9570
9571                 parser = &expression_parsers[token.type];
9572                 if (parser->infix_parser == NULL)
9573                         break;
9574                 if (parser->infix_precedence < precedence)
9575                         break;
9576
9577                 left = parser->infix_parser(left);
9578
9579                 assert(left != NULL);
9580                 assert(left->kind != EXPR_UNKNOWN);
9581                 left->base.source_position = source_position;
9582         }
9583
9584         return left;
9585 }
9586
9587 /**
9588  * Parse an expression.
9589  */
9590 static expression_t *parse_expression(void)
9591 {
9592         return parse_sub_expression(PREC_EXPRESSION);
9593 }
9594
9595 /**
9596  * Register a parser for a prefix-like operator.
9597  *
9598  * @param parser      the parser function
9599  * @param token_type  the token type of the prefix token
9600  */
9601 static void register_expression_parser(parse_expression_function parser,
9602                                        int token_type)
9603 {
9604         expression_parser_function_t *entry = &expression_parsers[token_type];
9605
9606         if (entry->parser != NULL) {
9607                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9608                 panic("trying to register multiple expression parsers for a token");
9609         }
9610         entry->parser = parser;
9611 }
9612
9613 /**
9614  * Register a parser for an infix operator with given precedence.
9615  *
9616  * @param parser      the parser function
9617  * @param token_type  the token type of the infix operator
9618  * @param precedence  the precedence of the operator
9619  */
9620 static void register_infix_parser(parse_expression_infix_function parser,
9621                 int token_type, precedence_t precedence)
9622 {
9623         expression_parser_function_t *entry = &expression_parsers[token_type];
9624
9625         if (entry->infix_parser != NULL) {
9626                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9627                 panic("trying to register multiple infix expression parsers for a "
9628                       "token");
9629         }
9630         entry->infix_parser     = parser;
9631         entry->infix_precedence = precedence;
9632 }
9633
9634 /**
9635  * Initialize the expression parsers.
9636  */
9637 static void init_expression_parsers(void)
9638 {
9639         memset(&expression_parsers, 0, sizeof(expression_parsers));
9640
9641         register_infix_parser(parse_array_expression,               '[',                    PREC_POSTFIX);
9642         register_infix_parser(parse_call_expression,                '(',                    PREC_POSTFIX);
9643         register_infix_parser(parse_select_expression,              '.',                    PREC_POSTFIX);
9644         register_infix_parser(parse_select_expression,              T_MINUSGREATER,         PREC_POSTFIX);
9645         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,   T_PLUSPLUS,             PREC_POSTFIX);
9646         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,   T_MINUSMINUS,           PREC_POSTFIX);
9647         register_infix_parser(parse_EXPR_BINARY_MUL,                '*',                    PREC_MULTIPLICATIVE);
9648         register_infix_parser(parse_EXPR_BINARY_DIV,                '/',                    PREC_MULTIPLICATIVE);
9649         register_infix_parser(parse_EXPR_BINARY_MOD,                '%',                    PREC_MULTIPLICATIVE);
9650         register_infix_parser(parse_EXPR_BINARY_ADD,                '+',                    PREC_ADDITIVE);
9651         register_infix_parser(parse_EXPR_BINARY_SUB,                '-',                    PREC_ADDITIVE);
9652         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,          T_LESSLESS,             PREC_SHIFT);
9653         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,         T_GREATERGREATER,       PREC_SHIFT);
9654         register_infix_parser(parse_EXPR_BINARY_LESS,               '<',                    PREC_RELATIONAL);
9655         register_infix_parser(parse_EXPR_BINARY_GREATER,            '>',                    PREC_RELATIONAL);
9656         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,          T_LESSEQUAL,            PREC_RELATIONAL);
9657         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL,       T_GREATEREQUAL,         PREC_RELATIONAL);
9658         register_infix_parser(parse_EXPR_BINARY_EQUAL,              T_EQUALEQUAL,           PREC_EQUALITY);
9659         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,           T_EXCLAMATIONMARKEQUAL, PREC_EQUALITY);
9660         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,        '&',                    PREC_AND);
9661         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,        '^',                    PREC_XOR);
9662         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,         '|',                    PREC_OR);
9663         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,        T_ANDAND,               PREC_LOGICAL_AND);
9664         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,         T_PIPEPIPE,             PREC_LOGICAL_OR);
9665         register_infix_parser(parse_conditional_expression,         '?',                    PREC_CONDITIONAL);
9666         register_infix_parser(parse_EXPR_BINARY_ASSIGN,             '=',                    PREC_ASSIGNMENT);
9667         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,         T_PLUSEQUAL,            PREC_ASSIGNMENT);
9668         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,         T_MINUSEQUAL,           PREC_ASSIGNMENT);
9669         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,         T_ASTERISKEQUAL,        PREC_ASSIGNMENT);
9670         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,         T_SLASHEQUAL,           PREC_ASSIGNMENT);
9671         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,         T_PERCENTEQUAL,         PREC_ASSIGNMENT);
9672         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,   T_LESSLESSEQUAL,        PREC_ASSIGNMENT);
9673         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,  T_GREATERGREATEREQUAL,  PREC_ASSIGNMENT);
9674         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN, T_ANDEQUAL,             PREC_ASSIGNMENT);
9675         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,  T_PIPEEQUAL,            PREC_ASSIGNMENT);
9676         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN, T_CARETEQUAL,           PREC_ASSIGNMENT);
9677         register_infix_parser(parse_EXPR_BINARY_COMMA,              ',',                    PREC_EXPRESSION);
9678
9679         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-');
9680         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+');
9681         register_expression_parser(parse_EXPR_UNARY_NOT,              '!');
9682         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~');
9683         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*');
9684         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&');
9685         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT, T_PLUSPLUS);
9686         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT, T_MINUSMINUS);
9687         register_expression_parser(parse_sizeof,                      T_sizeof);
9688         register_expression_parser(parse_alignof,                     T___alignof__);
9689         register_expression_parser(parse_extension,                   T___extension__);
9690         register_expression_parser(parse_builtin_classify_type,       T___builtin_classify_type);
9691         register_expression_parser(parse_delete,                      T_delete);
9692         register_expression_parser(parse_throw,                       T_throw);
9693 }
9694
9695 /**
9696  * Parse a asm statement arguments specification.
9697  */
9698 static asm_argument_t *parse_asm_arguments(bool is_out)
9699 {
9700         asm_argument_t  *result = NULL;
9701         asm_argument_t **anchor = &result;
9702
9703         while (token.type == T_STRING_LITERAL || token.type == '[') {
9704                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
9705                 memset(argument, 0, sizeof(argument[0]));
9706
9707                 if (token.type == '[') {
9708                         eat('[');
9709                         if (token.type != T_IDENTIFIER) {
9710                                 parse_error_expected("while parsing asm argument",
9711                                                      T_IDENTIFIER, NULL);
9712                                 return NULL;
9713                         }
9714                         argument->symbol = token.v.symbol;
9715
9716                         expect(']', end_error);
9717                 }
9718
9719                 argument->constraints = parse_string_literals();
9720                 expect('(', end_error);
9721                 add_anchor_token(')');
9722                 expression_t *expression = parse_expression();
9723                 rem_anchor_token(')');
9724                 if (is_out) {
9725                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
9726                          * change size or type representation (e.g. int -> long is ok, but
9727                          * int -> float is not) */
9728                         if (expression->kind == EXPR_UNARY_CAST) {
9729                                 type_t      *const type = expression->base.type;
9730                                 type_kind_t  const kind = type->kind;
9731                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
9732                                         unsigned flags;
9733                                         unsigned size;
9734                                         if (kind == TYPE_ATOMIC) {
9735                                                 atomic_type_kind_t const akind = type->atomic.akind;
9736                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9737                                                 size  = get_atomic_type_size(akind);
9738                                         } else {
9739                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9740                                                 size  = get_atomic_type_size(get_intptr_kind());
9741                                         }
9742
9743                                         do {
9744                                                 expression_t *const value      = expression->unary.value;
9745                                                 type_t       *const value_type = value->base.type;
9746                                                 type_kind_t   const value_kind = value_type->kind;
9747
9748                                                 unsigned value_flags;
9749                                                 unsigned value_size;
9750                                                 if (value_kind == TYPE_ATOMIC) {
9751                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
9752                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9753                                                         value_size  = get_atomic_type_size(value_akind);
9754                                                 } else if (value_kind == TYPE_POINTER) {
9755                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9756                                                         value_size  = get_atomic_type_size(get_intptr_kind());
9757                                                 } else {
9758                                                         break;
9759                                                 }
9760
9761                                                 if (value_flags != flags || value_size != size)
9762                                                         break;
9763
9764                                                 expression = value;
9765                                         } while (expression->kind == EXPR_UNARY_CAST);
9766                                 }
9767                         }
9768
9769                         if (!is_lvalue(expression)) {
9770                                 errorf(&expression->base.source_position,
9771                                        "asm output argument is not an lvalue");
9772                         }
9773
9774                         if (argument->constraints.begin[0] == '+')
9775                                 mark_vars_read(expression, NULL);
9776                 } else {
9777                         mark_vars_read(expression, NULL);
9778                 }
9779                 argument->expression = expression;
9780                 expect(')', end_error);
9781
9782                 set_address_taken(expression, true);
9783
9784                 *anchor = argument;
9785                 anchor  = &argument->next;
9786
9787                 if (token.type != ',')
9788                         break;
9789                 eat(',');
9790         }
9791
9792         return result;
9793 end_error:
9794         return NULL;
9795 }
9796
9797 /**
9798  * Parse a asm statement clobber specification.
9799  */
9800 static asm_clobber_t *parse_asm_clobbers(void)
9801 {
9802         asm_clobber_t *result = NULL;
9803         asm_clobber_t *last   = NULL;
9804
9805         while (token.type == T_STRING_LITERAL) {
9806                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
9807                 clobber->clobber       = parse_string_literals();
9808
9809                 if (last != NULL) {
9810                         last->next = clobber;
9811                 } else {
9812                         result = clobber;
9813                 }
9814                 last = clobber;
9815
9816                 if (token.type != ',')
9817                         break;
9818                 eat(',');
9819         }
9820
9821         return result;
9822 }
9823
9824 /**
9825  * Parse an asm statement.
9826  */
9827 static statement_t *parse_asm_statement(void)
9828 {
9829         statement_t     *statement     = allocate_statement_zero(STATEMENT_ASM);
9830         asm_statement_t *asm_statement = &statement->asms;
9831
9832         eat(T_asm);
9833
9834         if (token.type == T_volatile) {
9835                 next_token();
9836                 asm_statement->is_volatile = true;
9837         }
9838
9839         expect('(', end_error);
9840         add_anchor_token(')');
9841         add_anchor_token(':');
9842         asm_statement->asm_text = parse_string_literals();
9843
9844         if (token.type != ':') {
9845                 rem_anchor_token(':');
9846                 goto end_of_asm;
9847         }
9848         eat(':');
9849
9850         asm_statement->outputs = parse_asm_arguments(true);
9851         if (token.type != ':') {
9852                 rem_anchor_token(':');
9853                 goto end_of_asm;
9854         }
9855         eat(':');
9856
9857         asm_statement->inputs = parse_asm_arguments(false);
9858         if (token.type != ':') {
9859                 rem_anchor_token(':');
9860                 goto end_of_asm;
9861         }
9862         rem_anchor_token(':');
9863         eat(':');
9864
9865         asm_statement->clobbers = parse_asm_clobbers();
9866
9867 end_of_asm:
9868         rem_anchor_token(')');
9869         expect(')', end_error);
9870         expect(';', end_error);
9871
9872         if (asm_statement->outputs == NULL) {
9873                 /* GCC: An 'asm' instruction without any output operands will be treated
9874                  * identically to a volatile 'asm' instruction. */
9875                 asm_statement->is_volatile = true;
9876         }
9877
9878         return statement;
9879 end_error:
9880         return create_invalid_statement();
9881 }
9882
9883 /**
9884  * Parse a case statement.
9885  */
9886 static statement_t *parse_case_statement(void)
9887 {
9888         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9889         source_position_t *const pos       = &statement->base.source_position;
9890
9891         eat(T_case);
9892
9893         expression_t *const expression   = parse_expression();
9894         statement->case_label.expression = expression;
9895         if (!is_constant_expression(expression)) {
9896                 /* This check does not prevent the error message in all cases of an
9897                  * prior error while parsing the expression.  At least it catches the
9898                  * common case of a mistyped enum entry. */
9899                 if (is_type_valid(skip_typeref(expression->base.type))) {
9900                         errorf(pos, "case label does not reduce to an integer constant");
9901                 }
9902                 statement->case_label.is_bad = true;
9903         } else {
9904                 long const val = fold_constant(expression);
9905                 statement->case_label.first_case = val;
9906                 statement->case_label.last_case  = val;
9907         }
9908
9909         if (GNU_MODE) {
9910                 if (token.type == T_DOTDOTDOT) {
9911                         next_token();
9912                         expression_t *const end_range   = parse_expression();
9913                         statement->case_label.end_range = end_range;
9914                         if (!is_constant_expression(end_range)) {
9915                                 /* This check does not prevent the error message in all cases of an
9916                                  * prior error while parsing the expression.  At least it catches the
9917                                  * common case of a mistyped enum entry. */
9918                                 if (is_type_valid(skip_typeref(end_range->base.type))) {
9919                                         errorf(pos, "case range does not reduce to an integer constant");
9920                                 }
9921                                 statement->case_label.is_bad = true;
9922                         } else {
9923                                 long const val = fold_constant(end_range);
9924                                 statement->case_label.last_case = val;
9925
9926                                 if (warning.other && val < statement->case_label.first_case) {
9927                                         statement->case_label.is_empty_range = true;
9928                                         warningf(pos, "empty range specified");
9929                                 }
9930                         }
9931                 }
9932         }
9933
9934         PUSH_PARENT(statement);
9935
9936         expect(':', end_error);
9937 end_error:
9938
9939         if (current_switch != NULL) {
9940                 if (! statement->case_label.is_bad) {
9941                         /* Check for duplicate case values */
9942                         case_label_statement_t *c = &statement->case_label;
9943                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
9944                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
9945                                         continue;
9946
9947                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
9948                                         continue;
9949
9950                                 errorf(pos, "duplicate case value (previously used %P)",
9951                                        &l->base.source_position);
9952                                 break;
9953                         }
9954                 }
9955                 /* link all cases into the switch statement */
9956                 if (current_switch->last_case == NULL) {
9957                         current_switch->first_case      = &statement->case_label;
9958                 } else {
9959                         current_switch->last_case->next = &statement->case_label;
9960                 }
9961                 current_switch->last_case = &statement->case_label;
9962         } else {
9963                 errorf(pos, "case label not within a switch statement");
9964         }
9965
9966         statement_t *const inner_stmt = parse_statement();
9967         statement->case_label.statement = inner_stmt;
9968         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9969                 errorf(&inner_stmt->base.source_position, "declaration after case label");
9970         }
9971
9972         POP_PARENT;
9973         return statement;
9974 }
9975
9976 /**
9977  * Parse a default statement.
9978  */
9979 static statement_t *parse_default_statement(void)
9980 {
9981         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9982
9983         eat(T_default);
9984
9985         PUSH_PARENT(statement);
9986
9987         expect(':', end_error);
9988         if (current_switch != NULL) {
9989                 const case_label_statement_t *def_label = current_switch->default_label;
9990                 if (def_label != NULL) {
9991                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
9992                                &def_label->base.source_position);
9993                 } else {
9994                         current_switch->default_label = &statement->case_label;
9995
9996                         /* link all cases into the switch statement */
9997                         if (current_switch->last_case == NULL) {
9998                                 current_switch->first_case      = &statement->case_label;
9999                         } else {
10000                                 current_switch->last_case->next = &statement->case_label;
10001                         }
10002                         current_switch->last_case = &statement->case_label;
10003                 }
10004         } else {
10005                 errorf(&statement->base.source_position,
10006                         "'default' label not within a switch statement");
10007         }
10008
10009         statement_t *const inner_stmt = parse_statement();
10010         statement->case_label.statement = inner_stmt;
10011         if (inner_stmt->kind == STATEMENT_DECLARATION) {
10012                 errorf(&inner_stmt->base.source_position, "declaration after default label");
10013         }
10014
10015         POP_PARENT;
10016         return statement;
10017 end_error:
10018         POP_PARENT;
10019         return create_invalid_statement();
10020 }
10021
10022 /**
10023  * Parse a label statement.
10024  */
10025 static statement_t *parse_label_statement(void)
10026 {
10027         assert(token.type == T_IDENTIFIER);
10028         symbol_t *symbol = token.v.symbol;
10029         label_t  *label  = get_label(symbol);
10030
10031         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
10032         statement->label.label       = label;
10033
10034         next_token();
10035
10036         PUSH_PARENT(statement);
10037
10038         /* if statement is already set then the label is defined twice,
10039          * otherwise it was just mentioned in a goto/local label declaration so far
10040          */
10041         if (label->statement != NULL) {
10042                 errorf(HERE, "duplicate label '%Y' (declared %P)",
10043                        symbol, &label->base.source_position);
10044         } else {
10045                 label->base.source_position = token.source_position;
10046                 label->statement            = statement;
10047         }
10048
10049         eat(':');
10050
10051         if (token.type == '}') {
10052                 /* TODO only warn? */
10053                 if (warning.other && false) {
10054                         warningf(HERE, "label at end of compound statement");
10055                         statement->label.statement = create_empty_statement();
10056                 } else {
10057                         errorf(HERE, "label at end of compound statement");
10058                         statement->label.statement = create_invalid_statement();
10059                 }
10060         } else if (token.type == ';') {
10061                 /* Eat an empty statement here, to avoid the warning about an empty
10062                  * statement after a label.  label:; is commonly used to have a label
10063                  * before a closing brace. */
10064                 statement->label.statement = create_empty_statement();
10065                 next_token();
10066         } else {
10067                 statement_t *const inner_stmt = parse_statement();
10068                 statement->label.statement = inner_stmt;
10069                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
10070                         errorf(&inner_stmt->base.source_position, "declaration after label");
10071                 }
10072         }
10073
10074         /* remember the labels in a list for later checking */
10075         *label_anchor = &statement->label;
10076         label_anchor  = &statement->label.next;
10077
10078         POP_PARENT;
10079         return statement;
10080 }
10081
10082 /**
10083  * Parse an if statement.
10084  */
10085 static statement_t *parse_if(void)
10086 {
10087         statement_t *statement = allocate_statement_zero(STATEMENT_IF);
10088
10089         eat(T_if);
10090
10091         PUSH_PARENT(statement);
10092
10093         add_anchor_token('{');
10094
10095         expect('(', end_error);
10096         add_anchor_token(')');
10097         expression_t *const expr = parse_expression();
10098         statement->ifs.condition = expr;
10099         /* §6.8.4.1:1  The controlling expression of an if statement shall have
10100          *             scalar type. */
10101         semantic_condition(expr, "condition of 'if'-statment");
10102         mark_vars_read(expr, NULL);
10103         rem_anchor_token(')');
10104         expect(')', end_error);
10105
10106 end_error:
10107         rem_anchor_token('{');
10108
10109         add_anchor_token(T_else);
10110         statement_t *const true_stmt = parse_statement();
10111         statement->ifs.true_statement = true_stmt;
10112         rem_anchor_token(T_else);
10113
10114         if (token.type == T_else) {
10115                 next_token();
10116                 statement->ifs.false_statement = parse_statement();
10117         } else if (warning.parentheses &&
10118                         true_stmt->kind == STATEMENT_IF &&
10119                         true_stmt->ifs.false_statement != NULL) {
10120                 warningf(&true_stmt->base.source_position,
10121                                 "suggest explicit braces to avoid ambiguous 'else'");
10122         }
10123
10124         POP_PARENT;
10125         return statement;
10126 }
10127
10128 /**
10129  * Check that all enums are handled in a switch.
10130  *
10131  * @param statement  the switch statement to check
10132  */
10133 static void check_enum_cases(const switch_statement_t *statement)
10134 {
10135         const type_t *type = skip_typeref(statement->expression->base.type);
10136         if (! is_type_enum(type))
10137                 return;
10138         const enum_type_t *enumt = &type->enumt;
10139
10140         /* if we have a default, no warnings */
10141         if (statement->default_label != NULL)
10142                 return;
10143
10144         /* FIXME: calculation of value should be done while parsing */
10145         /* TODO: quadratic algorithm here. Change to an n log n one */
10146         long            last_value = -1;
10147         const entity_t *entry      = enumt->enume->base.next;
10148         for (; entry != NULL && entry->kind == ENTITY_ENUM_VALUE;
10149              entry = entry->base.next) {
10150                 const expression_t *expression = entry->enum_value.value;
10151                 long                value      = expression != NULL ? fold_constant(expression) : last_value + 1;
10152                 bool                found      = false;
10153                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
10154                         if (l->expression == NULL)
10155                                 continue;
10156                         if (l->first_case <= value && value <= l->last_case) {
10157                                 found = true;
10158                                 break;
10159                         }
10160                 }
10161                 if (! found) {
10162                         warningf(&statement->base.source_position,
10163                                  "enumeration value '%Y' not handled in switch",
10164                                  entry->base.symbol);
10165                 }
10166                 last_value = value;
10167         }
10168 }
10169
10170 /**
10171  * Parse a switch statement.
10172  */
10173 static statement_t *parse_switch(void)
10174 {
10175         statement_t *statement = allocate_statement_zero(STATEMENT_SWITCH);
10176
10177         eat(T_switch);
10178
10179         PUSH_PARENT(statement);
10180
10181         expect('(', end_error);
10182         add_anchor_token(')');
10183         expression_t *const expr = parse_expression();
10184         mark_vars_read(expr, NULL);
10185         type_t       *      type = skip_typeref(expr->base.type);
10186         if (is_type_integer(type)) {
10187                 type = promote_integer(type);
10188                 if (warning.traditional) {
10189                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
10190                                 warningf(&expr->base.source_position,
10191                                         "'%T' switch expression not converted to '%T' in ISO C",
10192                                         type, type_int);
10193                         }
10194                 }
10195         } else if (is_type_valid(type)) {
10196                 errorf(&expr->base.source_position,
10197                        "switch quantity is not an integer, but '%T'", type);
10198                 type = type_error_type;
10199         }
10200         statement->switchs.expression = create_implicit_cast(expr, type);
10201         expect(')', end_error);
10202         rem_anchor_token(')');
10203
10204         switch_statement_t *rem = current_switch;
10205         current_switch          = &statement->switchs;
10206         statement->switchs.body = parse_statement();
10207         current_switch          = rem;
10208
10209         if (warning.switch_default &&
10210             statement->switchs.default_label == NULL) {
10211                 warningf(&statement->base.source_position, "switch has no default case");
10212         }
10213         if (warning.switch_enum)
10214                 check_enum_cases(&statement->switchs);
10215
10216         POP_PARENT;
10217         return statement;
10218 end_error:
10219         POP_PARENT;
10220         return create_invalid_statement();
10221 }
10222
10223 static statement_t *parse_loop_body(statement_t *const loop)
10224 {
10225         statement_t *const rem = current_loop;
10226         current_loop = loop;
10227
10228         statement_t *const body = parse_statement();
10229
10230         current_loop = rem;
10231         return body;
10232 }
10233
10234 /**
10235  * Parse a while statement.
10236  */
10237 static statement_t *parse_while(void)
10238 {
10239         statement_t *statement = allocate_statement_zero(STATEMENT_WHILE);
10240
10241         eat(T_while);
10242
10243         PUSH_PARENT(statement);
10244
10245         expect('(', end_error);
10246         add_anchor_token(')');
10247         expression_t *const cond = parse_expression();
10248         statement->whiles.condition = cond;
10249         /* §6.8.5:2    The controlling expression of an iteration statement shall
10250          *             have scalar type. */
10251         semantic_condition(cond, "condition of 'while'-statement");
10252         mark_vars_read(cond, NULL);
10253         rem_anchor_token(')');
10254         expect(')', end_error);
10255
10256         statement->whiles.body = parse_loop_body(statement);
10257
10258         POP_PARENT;
10259         return statement;
10260 end_error:
10261         POP_PARENT;
10262         return create_invalid_statement();
10263 }
10264
10265 /**
10266  * Parse a do statement.
10267  */
10268 static statement_t *parse_do(void)
10269 {
10270         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
10271
10272         eat(T_do);
10273
10274         PUSH_PARENT(statement);
10275
10276         add_anchor_token(T_while);
10277         statement->do_while.body = parse_loop_body(statement);
10278         rem_anchor_token(T_while);
10279
10280         expect(T_while, end_error);
10281         expect('(', end_error);
10282         add_anchor_token(')');
10283         expression_t *const cond = parse_expression();
10284         statement->do_while.condition = cond;
10285         /* §6.8.5:2    The controlling expression of an iteration statement shall
10286          *             have scalar type. */
10287         semantic_condition(cond, "condition of 'do-while'-statement");
10288         mark_vars_read(cond, NULL);
10289         rem_anchor_token(')');
10290         expect(')', end_error);
10291         expect(';', end_error);
10292
10293         POP_PARENT;
10294         return statement;
10295 end_error:
10296         POP_PARENT;
10297         return create_invalid_statement();
10298 }
10299
10300 /**
10301  * Parse a for statement.
10302  */
10303 static statement_t *parse_for(void)
10304 {
10305         statement_t *statement = allocate_statement_zero(STATEMENT_FOR);
10306
10307         eat(T_for);
10308
10309         expect('(', end_error1);
10310         add_anchor_token(')');
10311
10312         PUSH_PARENT(statement);
10313
10314         size_t const  top       = environment_top();
10315         scope_t      *old_scope = scope_push(&statement->fors.scope);
10316
10317         if (token.type == ';') {
10318                 next_token();
10319         } else if (is_declaration_specifier(&token, false)) {
10320                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10321         } else {
10322                 add_anchor_token(';');
10323                 expression_t *const init = parse_expression();
10324                 statement->fors.initialisation = init;
10325                 mark_vars_read(init, ENT_ANY);
10326                 if (warning.unused_value && !expression_has_effect(init)) {
10327                         warningf(&init->base.source_position,
10328                                         "initialisation of 'for'-statement has no effect");
10329                 }
10330                 rem_anchor_token(';');
10331                 expect(';', end_error2);
10332         }
10333
10334         if (token.type != ';') {
10335                 add_anchor_token(';');
10336                 expression_t *const cond = parse_expression();
10337                 statement->fors.condition = cond;
10338                 /* §6.8.5:2    The controlling expression of an iteration statement
10339                  *             shall have scalar type. */
10340                 semantic_condition(cond, "condition of 'for'-statement");
10341                 mark_vars_read(cond, NULL);
10342                 rem_anchor_token(';');
10343         }
10344         expect(';', end_error2);
10345         if (token.type != ')') {
10346                 expression_t *const step = parse_expression();
10347                 statement->fors.step = step;
10348                 mark_vars_read(step, ENT_ANY);
10349                 if (warning.unused_value && !expression_has_effect(step)) {
10350                         warningf(&step->base.source_position,
10351                                  "step of 'for'-statement has no effect");
10352                 }
10353         }
10354         expect(')', end_error2);
10355         rem_anchor_token(')');
10356         statement->fors.body = parse_loop_body(statement);
10357
10358         assert(current_scope == &statement->fors.scope);
10359         scope_pop(old_scope);
10360         environment_pop_to(top);
10361
10362         POP_PARENT;
10363         return statement;
10364
10365 end_error2:
10366         POP_PARENT;
10367         rem_anchor_token(')');
10368         assert(current_scope == &statement->fors.scope);
10369         scope_pop(old_scope);
10370         environment_pop_to(top);
10371         /* fallthrough */
10372
10373 end_error1:
10374         return create_invalid_statement();
10375 }
10376
10377 /**
10378  * Parse a goto statement.
10379  */
10380 static statement_t *parse_goto(void)
10381 {
10382         statement_t *statement = allocate_statement_zero(STATEMENT_GOTO);
10383         eat(T_goto);
10384
10385         if (GNU_MODE && token.type == '*') {
10386                 next_token();
10387                 expression_t *expression = parse_expression();
10388                 mark_vars_read(expression, NULL);
10389
10390                 /* Argh: although documentation says the expression must be of type void*,
10391                  * gcc accepts anything that can be casted into void* without error */
10392                 type_t *type = expression->base.type;
10393
10394                 if (type != type_error_type) {
10395                         if (!is_type_pointer(type) && !is_type_integer(type)) {
10396                                 errorf(&expression->base.source_position,
10397                                         "cannot convert to a pointer type");
10398                         } else if (warning.other && type != type_void_ptr) {
10399                                 warningf(&expression->base.source_position,
10400                                         "type of computed goto expression should be 'void*' not '%T'", type);
10401                         }
10402                         expression = create_implicit_cast(expression, type_void_ptr);
10403                 }
10404
10405                 statement->gotos.expression = expression;
10406         } else {
10407                 if (token.type != T_IDENTIFIER) {
10408                         if (GNU_MODE)
10409                                 parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
10410                         else
10411                                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
10412                         eat_until_anchor();
10413                         goto end_error;
10414                 }
10415                 symbol_t *symbol = token.v.symbol;
10416                 next_token();
10417
10418                 statement->gotos.label = get_label(symbol);
10419         }
10420
10421         /* remember the goto's in a list for later checking */
10422         *goto_anchor = &statement->gotos;
10423         goto_anchor  = &statement->gotos.next;
10424
10425         expect(';', end_error);
10426
10427         return statement;
10428 end_error:
10429         return create_invalid_statement();
10430 }
10431
10432 /**
10433  * Parse a continue statement.
10434  */
10435 static statement_t *parse_continue(void)
10436 {
10437         if (current_loop == NULL) {
10438                 errorf(HERE, "continue statement not within loop");
10439         }
10440
10441         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
10442
10443         eat(T_continue);
10444         expect(';', end_error);
10445
10446 end_error:
10447         return statement;
10448 }
10449
10450 /**
10451  * Parse a break statement.
10452  */
10453 static statement_t *parse_break(void)
10454 {
10455         if (current_switch == NULL && current_loop == NULL) {
10456                 errorf(HERE, "break statement not within loop or switch");
10457         }
10458
10459         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
10460
10461         eat(T_break);
10462         expect(';', end_error);
10463
10464 end_error:
10465         return statement;
10466 }
10467
10468 /**
10469  * Parse a __leave statement.
10470  */
10471 static statement_t *parse_leave_statement(void)
10472 {
10473         if (current_try == NULL) {
10474                 errorf(HERE, "__leave statement not within __try");
10475         }
10476
10477         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
10478
10479         eat(T___leave);
10480         expect(';', end_error);
10481
10482 end_error:
10483         return statement;
10484 }
10485
10486 /**
10487  * Check if a given entity represents a local variable.
10488  */
10489 static bool is_local_variable(const entity_t *entity)
10490 {
10491         if (entity->kind != ENTITY_VARIABLE)
10492                 return false;
10493
10494         switch ((storage_class_tag_t) entity->declaration.storage_class) {
10495         case STORAGE_CLASS_AUTO:
10496         case STORAGE_CLASS_REGISTER: {
10497                 const type_t *type = skip_typeref(entity->declaration.type);
10498                 if (is_type_function(type)) {
10499                         return false;
10500                 } else {
10501                         return true;
10502                 }
10503         }
10504         default:
10505                 return false;
10506         }
10507 }
10508
10509 /**
10510  * Check if a given expression represents a local variable.
10511  */
10512 static bool expression_is_local_variable(const expression_t *expression)
10513 {
10514         if (expression->base.kind != EXPR_REFERENCE) {
10515                 return false;
10516         }
10517         const entity_t *entity = expression->reference.entity;
10518         return is_local_variable(entity);
10519 }
10520
10521 /**
10522  * Check if a given expression represents a local variable and
10523  * return its declaration then, else return NULL.
10524  */
10525 entity_t *expression_is_variable(const expression_t *expression)
10526 {
10527         if (expression->base.kind != EXPR_REFERENCE) {
10528                 return NULL;
10529         }
10530         entity_t *entity = expression->reference.entity;
10531         if (entity->kind != ENTITY_VARIABLE)
10532                 return NULL;
10533
10534         return entity;
10535 }
10536
10537 /**
10538  * Parse a return statement.
10539  */
10540 static statement_t *parse_return(void)
10541 {
10542         eat(T_return);
10543
10544         statement_t *statement = allocate_statement_zero(STATEMENT_RETURN);
10545
10546         expression_t *return_value = NULL;
10547         if (token.type != ';') {
10548                 return_value = parse_expression();
10549                 mark_vars_read(return_value, NULL);
10550         }
10551
10552         const type_t *const func_type = skip_typeref(current_function->base.type);
10553         assert(is_type_function(func_type));
10554         type_t *const return_type = skip_typeref(func_type->function.return_type);
10555
10556         source_position_t const *const pos = &statement->base.source_position;
10557         if (return_value != NULL) {
10558                 type_t *return_value_type = skip_typeref(return_value->base.type);
10559
10560                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10561                         if (is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
10562                                 /* ISO/IEC 14882:1998(E) §6.6.3:2 */
10563                                 /* Only warn in C mode, because GCC does the same */
10564                                 if (c_mode & _CXX || strict_mode) {
10565                                         errorf(pos,
10566                                                         "'return' with a value, in function returning 'void'");
10567                                 } else if (warning.other) {
10568                                         warningf(pos,
10569                                                         "'return' with a value, in function returning 'void'");
10570                                 }
10571                         } else if (!(c_mode & _CXX)) { /* ISO/IEC 14882:1998(E) §6.6.3:3 */
10572                                 /* Only warn in C mode, because GCC does the same */
10573                                 if (strict_mode) {
10574                                         errorf(pos,
10575                                                         "'return' with expression in function return 'void'");
10576                                 } else if (warning.other) {
10577                                         warningf(pos,
10578                                                         "'return' with expression in function return 'void'");
10579                                 }
10580                         }
10581                 } else {
10582                         assign_error_t error = semantic_assign(return_type, return_value);
10583                         report_assign_error(error, return_type, return_value, "'return'",
10584                                         pos);
10585                 }
10586                 return_value = create_implicit_cast(return_value, return_type);
10587                 /* check for returning address of a local var */
10588                 if (warning.other && return_value != NULL
10589                                 && return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
10590                         const expression_t *expression = return_value->unary.value;
10591                         if (expression_is_local_variable(expression)) {
10592                                 warningf(pos, "function returns address of local variable");
10593                         }
10594                 }
10595         } else if (warning.other && !is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10596                 /* ISO/IEC 14882:1998(E) §6.6.3:3 */
10597                 if (c_mode & _CXX || strict_mode) {
10598                         errorf(pos,
10599                                         "'return' without value, in function returning non-void");
10600                 } else {
10601                         warningf(pos,
10602                                         "'return' without value, in function returning non-void");
10603                 }
10604         }
10605         statement->returns.value = return_value;
10606
10607         expect(';', end_error);
10608
10609 end_error:
10610         return statement;
10611 }
10612
10613 /**
10614  * Parse a declaration statement.
10615  */
10616 static statement_t *parse_declaration_statement(void)
10617 {
10618         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10619
10620         entity_t *before = current_scope->last_entity;
10621         if (GNU_MODE) {
10622                 parse_external_declaration();
10623         } else {
10624                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10625         }
10626
10627         declaration_statement_t *const decl  = &statement->declaration;
10628         entity_t                *const begin =
10629                 before != NULL ? before->base.next : current_scope->entities;
10630         decl->declarations_begin = begin;
10631         decl->declarations_end   = begin != NULL ? current_scope->last_entity : NULL;
10632
10633         return statement;
10634 }
10635
10636 /**
10637  * Parse an expression statement, ie. expr ';'.
10638  */
10639 static statement_t *parse_expression_statement(void)
10640 {
10641         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10642
10643         expression_t *const expr         = parse_expression();
10644         statement->expression.expression = expr;
10645         mark_vars_read(expr, ENT_ANY);
10646
10647         expect(';', end_error);
10648
10649 end_error:
10650         return statement;
10651 }
10652
10653 /**
10654  * Parse a microsoft __try { } __finally { } or
10655  * __try{ } __except() { }
10656  */
10657 static statement_t *parse_ms_try_statment(void)
10658 {
10659         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
10660         eat(T___try);
10661
10662         PUSH_PARENT(statement);
10663
10664         ms_try_statement_t *rem = current_try;
10665         current_try = &statement->ms_try;
10666         statement->ms_try.try_statement = parse_compound_statement(false);
10667         current_try = rem;
10668
10669         POP_PARENT;
10670
10671         if (token.type == T___except) {
10672                 eat(T___except);
10673                 expect('(', end_error);
10674                 add_anchor_token(')');
10675                 expression_t *const expr = parse_expression();
10676                 mark_vars_read(expr, NULL);
10677                 type_t       *      type = skip_typeref(expr->base.type);
10678                 if (is_type_integer(type)) {
10679                         type = promote_integer(type);
10680                 } else if (is_type_valid(type)) {
10681                         errorf(&expr->base.source_position,
10682                                "__expect expression is not an integer, but '%T'", type);
10683                         type = type_error_type;
10684                 }
10685                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
10686                 rem_anchor_token(')');
10687                 expect(')', end_error);
10688                 statement->ms_try.final_statement = parse_compound_statement(false);
10689         } else if (token.type == T__finally) {
10690                 eat(T___finally);
10691                 statement->ms_try.final_statement = parse_compound_statement(false);
10692         } else {
10693                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
10694                 return create_invalid_statement();
10695         }
10696         return statement;
10697 end_error:
10698         return create_invalid_statement();
10699 }
10700
10701 static statement_t *parse_empty_statement(void)
10702 {
10703         if (warning.empty_statement) {
10704                 warningf(HERE, "statement is empty");
10705         }
10706         statement_t *const statement = create_empty_statement();
10707         eat(';');
10708         return statement;
10709 }
10710
10711 static statement_t *parse_local_label_declaration(void)
10712 {
10713         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10714
10715         eat(T___label__);
10716
10717         entity_t *begin = NULL, *end = NULL;
10718
10719         while (true) {
10720                 if (token.type != T_IDENTIFIER) {
10721                         parse_error_expected("while parsing local label declaration",
10722                                 T_IDENTIFIER, NULL);
10723                         goto end_error;
10724                 }
10725                 symbol_t *symbol = token.v.symbol;
10726                 entity_t *entity = get_entity(symbol, NAMESPACE_LABEL);
10727                 if (entity != NULL && entity->base.parent_scope == current_scope) {
10728                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition %P)",
10729                                symbol, &entity->base.source_position);
10730                 } else {
10731                         entity = allocate_entity_zero(ENTITY_LOCAL_LABEL);
10732
10733                         entity->base.parent_scope    = current_scope;
10734                         entity->base.namespc         = NAMESPACE_LABEL;
10735                         entity->base.source_position = token.source_position;
10736                         entity->base.symbol          = symbol;
10737
10738                         if (end != NULL)
10739                                 end->base.next = entity;
10740                         end = entity;
10741                         if (begin == NULL)
10742                                 begin = entity;
10743
10744                         environment_push(entity);
10745                 }
10746                 next_token();
10747
10748                 if (token.type != ',')
10749                         break;
10750                 next_token();
10751         }
10752         eat(';');
10753 end_error:
10754         statement->declaration.declarations_begin = begin;
10755         statement->declaration.declarations_end   = end;
10756         return statement;
10757 }
10758
10759 static void parse_namespace_definition(void)
10760 {
10761         eat(T_namespace);
10762
10763         entity_t *entity = NULL;
10764         symbol_t *symbol = NULL;
10765
10766         if (token.type == T_IDENTIFIER) {
10767                 symbol = token.v.symbol;
10768                 next_token();
10769
10770                 entity = get_entity(symbol, NAMESPACE_NORMAL);
10771                 if (entity       != NULL             &&
10772                                 entity->kind != ENTITY_NAMESPACE &&
10773                                 entity->base.parent_scope == current_scope) {
10774                         if (!is_error_entity(entity)) {
10775                                 error_redefined_as_different_kind(&token.source_position,
10776                                                 entity, ENTITY_NAMESPACE);
10777                         }
10778                         entity = NULL;
10779                 }
10780         }
10781
10782         if (entity == NULL) {
10783                 entity                       = allocate_entity_zero(ENTITY_NAMESPACE);
10784                 entity->base.symbol          = symbol;
10785                 entity->base.source_position = token.source_position;
10786                 entity->base.namespc         = NAMESPACE_NORMAL;
10787                 entity->base.parent_scope    = current_scope;
10788         }
10789
10790         if (token.type == '=') {
10791                 /* TODO: parse namespace alias */
10792                 panic("namespace alias definition not supported yet");
10793         }
10794
10795         environment_push(entity);
10796         append_entity(current_scope, entity);
10797
10798         size_t const  top       = environment_top();
10799         scope_t      *old_scope = scope_push(&entity->namespacee.members);
10800
10801         expect('{', end_error);
10802         parse_externals();
10803         expect('}', end_error);
10804
10805 end_error:
10806         assert(current_scope == &entity->namespacee.members);
10807         scope_pop(old_scope);
10808         environment_pop_to(top);
10809 }
10810
10811 /**
10812  * Parse a statement.
10813  * There's also parse_statement() which additionally checks for
10814  * "statement has no effect" warnings
10815  */
10816 static statement_t *intern_parse_statement(void)
10817 {
10818         statement_t *statement = NULL;
10819
10820         /* declaration or statement */
10821         add_anchor_token(';');
10822         switch (token.type) {
10823         case T_IDENTIFIER: {
10824                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
10825                 if (la1_type == ':') {
10826                         statement = parse_label_statement();
10827                 } else if (is_typedef_symbol(token.v.symbol)) {
10828                         statement = parse_declaration_statement();
10829                 } else {
10830                         /* it's an identifier, the grammar says this must be an
10831                          * expression statement. However it is common that users mistype
10832                          * declaration types, so we guess a bit here to improve robustness
10833                          * for incorrect programs */
10834                         switch (la1_type) {
10835                         case '&':
10836                         case '*':
10837                                 if (get_entity(token.v.symbol, NAMESPACE_NORMAL) != NULL)
10838                                         goto expression_statment;
10839                                 /* FALLTHROUGH */
10840
10841                         DECLARATION_START
10842                         case T_IDENTIFIER:
10843                                 statement = parse_declaration_statement();
10844                                 break;
10845
10846                         default:
10847 expression_statment:
10848                                 statement = parse_expression_statement();
10849                                 break;
10850                         }
10851                 }
10852                 break;
10853         }
10854
10855         case T___extension__:
10856                 /* This can be a prefix to a declaration or an expression statement.
10857                  * We simply eat it now and parse the rest with tail recursion. */
10858                 do {
10859                         next_token();
10860                 } while (token.type == T___extension__);
10861                 bool old_gcc_extension = in_gcc_extension;
10862                 in_gcc_extension       = true;
10863                 statement = intern_parse_statement();
10864                 in_gcc_extension = old_gcc_extension;
10865                 break;
10866
10867         DECLARATION_START
10868                 statement = parse_declaration_statement();
10869                 break;
10870
10871         case T___label__:
10872                 statement = parse_local_label_declaration();
10873                 break;
10874
10875         case ';':         statement = parse_empty_statement();         break;
10876         case '{':         statement = parse_compound_statement(false); break;
10877         case T___leave:   statement = parse_leave_statement();         break;
10878         case T___try:     statement = parse_ms_try_statment();         break;
10879         case T_asm:       statement = parse_asm_statement();           break;
10880         case T_break:     statement = parse_break();                   break;
10881         case T_case:      statement = parse_case_statement();          break;
10882         case T_continue:  statement = parse_continue();                break;
10883         case T_default:   statement = parse_default_statement();       break;
10884         case T_do:        statement = parse_do();                      break;
10885         case T_for:       statement = parse_for();                     break;
10886         case T_goto:      statement = parse_goto();                    break;
10887         case T_if:        statement = parse_if();                      break;
10888         case T_return:    statement = parse_return();                  break;
10889         case T_switch:    statement = parse_switch();                  break;
10890         case T_while:     statement = parse_while();                   break;
10891
10892         EXPRESSION_START
10893                 statement = parse_expression_statement();
10894                 break;
10895
10896         default:
10897                 errorf(HERE, "unexpected token %K while parsing statement", &token);
10898                 statement = create_invalid_statement();
10899                 if (!at_anchor())
10900                         next_token();
10901                 break;
10902         }
10903         rem_anchor_token(';');
10904
10905         assert(statement != NULL
10906                         && statement->base.source_position.input_name != NULL);
10907
10908         return statement;
10909 }
10910
10911 /**
10912  * parse a statement and emits "statement has no effect" warning if needed
10913  * (This is really a wrapper around intern_parse_statement with check for 1
10914  *  single warning. It is needed, because for statement expressions we have
10915  *  to avoid the warning on the last statement)
10916  */
10917 static statement_t *parse_statement(void)
10918 {
10919         statement_t *statement = intern_parse_statement();
10920
10921         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
10922                 expression_t *expression = statement->expression.expression;
10923                 if (!expression_has_effect(expression)) {
10924                         warningf(&expression->base.source_position,
10925                                         "statement has no effect");
10926                 }
10927         }
10928
10929         return statement;
10930 }
10931
10932 /**
10933  * Parse a compound statement.
10934  */
10935 static statement_t *parse_compound_statement(bool inside_expression_statement)
10936 {
10937         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
10938
10939         PUSH_PARENT(statement);
10940
10941         eat('{');
10942         add_anchor_token('}');
10943         /* tokens, which can start a statement */
10944         /* TODO MS, __builtin_FOO */
10945         add_anchor_token('!');
10946         add_anchor_token('&');
10947         add_anchor_token('(');
10948         add_anchor_token('*');
10949         add_anchor_token('+');
10950         add_anchor_token('-');
10951         add_anchor_token('{');
10952         add_anchor_token('~');
10953         add_anchor_token(T_CHARACTER_CONSTANT);
10954         add_anchor_token(T_COLONCOLON);
10955         add_anchor_token(T_FLOATINGPOINT);
10956         add_anchor_token(T_IDENTIFIER);
10957         add_anchor_token(T_INTEGER);
10958         add_anchor_token(T_MINUSMINUS);
10959         add_anchor_token(T_PLUSPLUS);
10960         add_anchor_token(T_STRING_LITERAL);
10961         add_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10962         add_anchor_token(T_WIDE_STRING_LITERAL);
10963         add_anchor_token(T__Bool);
10964         add_anchor_token(T__Complex);
10965         add_anchor_token(T__Imaginary);
10966         add_anchor_token(T___FUNCTION__);
10967         add_anchor_token(T___PRETTY_FUNCTION__);
10968         add_anchor_token(T___alignof__);
10969         add_anchor_token(T___attribute__);
10970         add_anchor_token(T___builtin_va_start);
10971         add_anchor_token(T___extension__);
10972         add_anchor_token(T___func__);
10973         add_anchor_token(T___imag__);
10974         add_anchor_token(T___label__);
10975         add_anchor_token(T___real__);
10976         add_anchor_token(T___thread);
10977         add_anchor_token(T_asm);
10978         add_anchor_token(T_auto);
10979         add_anchor_token(T_bool);
10980         add_anchor_token(T_break);
10981         add_anchor_token(T_case);
10982         add_anchor_token(T_char);
10983         add_anchor_token(T_class);
10984         add_anchor_token(T_const);
10985         add_anchor_token(T_const_cast);
10986         add_anchor_token(T_continue);
10987         add_anchor_token(T_default);
10988         add_anchor_token(T_delete);
10989         add_anchor_token(T_double);
10990         add_anchor_token(T_do);
10991         add_anchor_token(T_dynamic_cast);
10992         add_anchor_token(T_enum);
10993         add_anchor_token(T_extern);
10994         add_anchor_token(T_false);
10995         add_anchor_token(T_float);
10996         add_anchor_token(T_for);
10997         add_anchor_token(T_goto);
10998         add_anchor_token(T_if);
10999         add_anchor_token(T_inline);
11000         add_anchor_token(T_int);
11001         add_anchor_token(T_long);
11002         add_anchor_token(T_new);
11003         add_anchor_token(T_operator);
11004         add_anchor_token(T_register);
11005         add_anchor_token(T_reinterpret_cast);
11006         add_anchor_token(T_restrict);
11007         add_anchor_token(T_return);
11008         add_anchor_token(T_short);
11009         add_anchor_token(T_signed);
11010         add_anchor_token(T_sizeof);
11011         add_anchor_token(T_static);
11012         add_anchor_token(T_static_cast);
11013         add_anchor_token(T_struct);
11014         add_anchor_token(T_switch);
11015         add_anchor_token(T_template);
11016         add_anchor_token(T_this);
11017         add_anchor_token(T_throw);
11018         add_anchor_token(T_true);
11019         add_anchor_token(T_try);
11020         add_anchor_token(T_typedef);
11021         add_anchor_token(T_typeid);
11022         add_anchor_token(T_typename);
11023         add_anchor_token(T_typeof);
11024         add_anchor_token(T_union);
11025         add_anchor_token(T_unsigned);
11026         add_anchor_token(T_using);
11027         add_anchor_token(T_void);
11028         add_anchor_token(T_volatile);
11029         add_anchor_token(T_wchar_t);
11030         add_anchor_token(T_while);
11031
11032         size_t const  top       = environment_top();
11033         scope_t      *old_scope = scope_push(&statement->compound.scope);
11034
11035         statement_t **anchor            = &statement->compound.statements;
11036         bool          only_decls_so_far = true;
11037         while (token.type != '}') {
11038                 if (token.type == T_EOF) {
11039                         errorf(&statement->base.source_position,
11040                                "EOF while parsing compound statement");
11041                         break;
11042                 }
11043                 statement_t *sub_statement = intern_parse_statement();
11044                 if (is_invalid_statement(sub_statement)) {
11045                         /* an error occurred. if we are at an anchor, return */
11046                         if (at_anchor())
11047                                 goto end_error;
11048                         continue;
11049                 }
11050
11051                 if (warning.declaration_after_statement) {
11052                         if (sub_statement->kind != STATEMENT_DECLARATION) {
11053                                 only_decls_so_far = false;
11054                         } else if (!only_decls_so_far) {
11055                                 warningf(&sub_statement->base.source_position,
11056                                          "ISO C90 forbids mixed declarations and code");
11057                         }
11058                 }
11059
11060                 *anchor = sub_statement;
11061
11062                 while (sub_statement->base.next != NULL)
11063                         sub_statement = sub_statement->base.next;
11064
11065                 anchor = &sub_statement->base.next;
11066         }
11067         next_token();
11068
11069         /* look over all statements again to produce no effect warnings */
11070         if (warning.unused_value) {
11071                 statement_t *sub_statement = statement->compound.statements;
11072                 for (; sub_statement != NULL; sub_statement = sub_statement->base.next) {
11073                         if (sub_statement->kind != STATEMENT_EXPRESSION)
11074                                 continue;
11075                         /* don't emit a warning for the last expression in an expression
11076                          * statement as it has always an effect */
11077                         if (inside_expression_statement && sub_statement->base.next == NULL)
11078                                 continue;
11079
11080                         expression_t *expression = sub_statement->expression.expression;
11081                         if (!expression_has_effect(expression)) {
11082                                 warningf(&expression->base.source_position,
11083                                          "statement has no effect");
11084                         }
11085                 }
11086         }
11087
11088 end_error:
11089         rem_anchor_token(T_while);
11090         rem_anchor_token(T_wchar_t);
11091         rem_anchor_token(T_volatile);
11092         rem_anchor_token(T_void);
11093         rem_anchor_token(T_using);
11094         rem_anchor_token(T_unsigned);
11095         rem_anchor_token(T_union);
11096         rem_anchor_token(T_typeof);
11097         rem_anchor_token(T_typename);
11098         rem_anchor_token(T_typeid);
11099         rem_anchor_token(T_typedef);
11100         rem_anchor_token(T_try);
11101         rem_anchor_token(T_true);
11102         rem_anchor_token(T_throw);
11103         rem_anchor_token(T_this);
11104         rem_anchor_token(T_template);
11105         rem_anchor_token(T_switch);
11106         rem_anchor_token(T_struct);
11107         rem_anchor_token(T_static_cast);
11108         rem_anchor_token(T_static);
11109         rem_anchor_token(T_sizeof);
11110         rem_anchor_token(T_signed);
11111         rem_anchor_token(T_short);
11112         rem_anchor_token(T_return);
11113         rem_anchor_token(T_restrict);
11114         rem_anchor_token(T_reinterpret_cast);
11115         rem_anchor_token(T_register);
11116         rem_anchor_token(T_operator);
11117         rem_anchor_token(T_new);
11118         rem_anchor_token(T_long);
11119         rem_anchor_token(T_int);
11120         rem_anchor_token(T_inline);
11121         rem_anchor_token(T_if);
11122         rem_anchor_token(T_goto);
11123         rem_anchor_token(T_for);
11124         rem_anchor_token(T_float);
11125         rem_anchor_token(T_false);
11126         rem_anchor_token(T_extern);
11127         rem_anchor_token(T_enum);
11128         rem_anchor_token(T_dynamic_cast);
11129         rem_anchor_token(T_do);
11130         rem_anchor_token(T_double);
11131         rem_anchor_token(T_delete);
11132         rem_anchor_token(T_default);
11133         rem_anchor_token(T_continue);
11134         rem_anchor_token(T_const_cast);
11135         rem_anchor_token(T_const);
11136         rem_anchor_token(T_class);
11137         rem_anchor_token(T_char);
11138         rem_anchor_token(T_case);
11139         rem_anchor_token(T_break);
11140         rem_anchor_token(T_bool);
11141         rem_anchor_token(T_auto);
11142         rem_anchor_token(T_asm);
11143         rem_anchor_token(T___thread);
11144         rem_anchor_token(T___real__);
11145         rem_anchor_token(T___label__);
11146         rem_anchor_token(T___imag__);
11147         rem_anchor_token(T___func__);
11148         rem_anchor_token(T___extension__);
11149         rem_anchor_token(T___builtin_va_start);
11150         rem_anchor_token(T___attribute__);
11151         rem_anchor_token(T___alignof__);
11152         rem_anchor_token(T___PRETTY_FUNCTION__);
11153         rem_anchor_token(T___FUNCTION__);
11154         rem_anchor_token(T__Imaginary);
11155         rem_anchor_token(T__Complex);
11156         rem_anchor_token(T__Bool);
11157         rem_anchor_token(T_WIDE_STRING_LITERAL);
11158         rem_anchor_token(T_WIDE_CHARACTER_CONSTANT);
11159         rem_anchor_token(T_STRING_LITERAL);
11160         rem_anchor_token(T_PLUSPLUS);
11161         rem_anchor_token(T_MINUSMINUS);
11162         rem_anchor_token(T_INTEGER);
11163         rem_anchor_token(T_IDENTIFIER);
11164         rem_anchor_token(T_FLOATINGPOINT);
11165         rem_anchor_token(T_COLONCOLON);
11166         rem_anchor_token(T_CHARACTER_CONSTANT);
11167         rem_anchor_token('~');
11168         rem_anchor_token('{');
11169         rem_anchor_token('-');
11170         rem_anchor_token('+');
11171         rem_anchor_token('*');
11172         rem_anchor_token('(');
11173         rem_anchor_token('&');
11174         rem_anchor_token('!');
11175         rem_anchor_token('}');
11176         assert(current_scope == &statement->compound.scope);
11177         scope_pop(old_scope);
11178         environment_pop_to(top);
11179
11180         POP_PARENT;
11181         return statement;
11182 }
11183
11184 /**
11185  * Check for unused global static functions and variables
11186  */
11187 static void check_unused_globals(void)
11188 {
11189         if (!warning.unused_function && !warning.unused_variable)
11190                 return;
11191
11192         for (const entity_t *entity = file_scope->entities; entity != NULL;
11193              entity = entity->base.next) {
11194                 if (!is_declaration(entity))
11195                         continue;
11196
11197                 const declaration_t *declaration = &entity->declaration;
11198                 if (declaration->used                  ||
11199                     declaration->modifiers & DM_UNUSED ||
11200                     declaration->modifiers & DM_USED   ||
11201                     declaration->storage_class != STORAGE_CLASS_STATIC)
11202                         continue;
11203
11204                 type_t *const type = declaration->type;
11205                 const char *s;
11206                 if (entity->kind == ENTITY_FUNCTION) {
11207                         /* inhibit warning for static inline functions */
11208                         if (entity->function.is_inline)
11209                                 continue;
11210
11211                         s = entity->function.statement != NULL ? "defined" : "declared";
11212                 } else {
11213                         s = "defined";
11214                 }
11215
11216                 warningf(&declaration->base.source_position, "'%#T' %s but not used",
11217                         type, declaration->base.symbol, s);
11218         }
11219 }
11220
11221 static void parse_global_asm(void)
11222 {
11223         statement_t *statement = allocate_statement_zero(STATEMENT_ASM);
11224
11225         eat(T_asm);
11226         expect('(', end_error);
11227
11228         statement->asms.asm_text = parse_string_literals();
11229         statement->base.next     = unit->global_asm;
11230         unit->global_asm         = statement;
11231
11232         expect(')', end_error);
11233         expect(';', end_error);
11234
11235 end_error:;
11236 }
11237
11238 static void parse_linkage_specification(void)
11239 {
11240         eat(T_extern);
11241         assert(token.type == T_STRING_LITERAL);
11242
11243         const char *linkage = parse_string_literals().begin;
11244
11245         linkage_kind_t old_linkage = current_linkage;
11246         linkage_kind_t new_linkage;
11247         if (strcmp(linkage, "C") == 0) {
11248                 new_linkage = LINKAGE_C;
11249         } else if (strcmp(linkage, "C++") == 0) {
11250                 new_linkage = LINKAGE_CXX;
11251         } else {
11252                 errorf(HERE, "linkage string \"%s\" not recognized", linkage);
11253                 new_linkage = LINKAGE_INVALID;
11254         }
11255         current_linkage = new_linkage;
11256
11257         if (token.type == '{') {
11258                 next_token();
11259                 parse_externals();
11260                 expect('}', end_error);
11261         } else {
11262                 parse_external();
11263         }
11264
11265 end_error:
11266         assert(current_linkage == new_linkage);
11267         current_linkage = old_linkage;
11268 }
11269
11270 static void parse_external(void)
11271 {
11272         switch (token.type) {
11273                 DECLARATION_START_NO_EXTERN
11274                 case T_IDENTIFIER:
11275                 case T___extension__:
11276                 /* tokens below are for implicit int */
11277                 case '&': /* & x; -> int& x; (and error later, because C++ has no
11278                              implicit int) */
11279                 case '*': /* * x; -> int* x; */
11280                 case '(': /* (x); -> int (x); */
11281                         parse_external_declaration();
11282                         return;
11283
11284                 case T_extern:
11285                         if (look_ahead(1)->type == T_STRING_LITERAL) {
11286                                 parse_linkage_specification();
11287                         } else {
11288                                 parse_external_declaration();
11289                         }
11290                         return;
11291
11292                 case T_asm:
11293                         parse_global_asm();
11294                         return;
11295
11296                 case T_namespace:
11297                         parse_namespace_definition();
11298                         return;
11299
11300                 case ';':
11301                         if (!strict_mode) {
11302                                 if (warning.other)
11303                                         warningf(HERE, "stray ';' outside of function");
11304                                 next_token();
11305                                 return;
11306                         }
11307                         /* FALLTHROUGH */
11308
11309                 default:
11310                         errorf(HERE, "stray %K outside of function", &token);
11311                         if (token.type == '(' || token.type == '{' || token.type == '[')
11312                                 eat_until_matching_token(token.type);
11313                         next_token();
11314                         return;
11315         }
11316 }
11317
11318 static void parse_externals(void)
11319 {
11320         add_anchor_token('}');
11321         add_anchor_token(T_EOF);
11322
11323 #ifndef NDEBUG
11324         unsigned char token_anchor_copy[T_LAST_TOKEN];
11325         memcpy(token_anchor_copy, token_anchor_set, sizeof(token_anchor_copy));
11326 #endif
11327
11328         while (token.type != T_EOF && token.type != '}') {
11329 #ifndef NDEBUG
11330                 bool anchor_leak = false;
11331                 for (int i = 0; i != T_LAST_TOKEN; ++i) {
11332                         unsigned char count = token_anchor_set[i] - token_anchor_copy[i];
11333                         if (count != 0) {
11334                                 errorf(HERE, "Leaked anchor token %k %d times", i, count);
11335                                 anchor_leak = true;
11336                         }
11337                 }
11338                 if (in_gcc_extension) {
11339                         errorf(HERE, "Leaked __extension__");
11340                         anchor_leak = true;
11341                 }
11342
11343                 if (anchor_leak)
11344                         abort();
11345 #endif
11346
11347                 parse_external();
11348         }
11349
11350         rem_anchor_token(T_EOF);
11351         rem_anchor_token('}');
11352 }
11353
11354 /**
11355  * Parse a translation unit.
11356  */
11357 static void parse_translation_unit(void)
11358 {
11359         add_anchor_token(T_EOF);
11360
11361         while (true) {
11362                 parse_externals();
11363
11364                 if (token.type == T_EOF)
11365                         break;
11366
11367                 errorf(HERE, "stray %K outside of function", &token);
11368                 if (token.type == '(' || token.type == '{' || token.type == '[')
11369                         eat_until_matching_token(token.type);
11370                 next_token();
11371         }
11372 }
11373
11374 /**
11375  * Parse the input.
11376  *
11377  * @return  the translation unit or NULL if errors occurred.
11378  */
11379 void start_parsing(void)
11380 {
11381         environment_stack = NEW_ARR_F(stack_entry_t, 0);
11382         label_stack       = NEW_ARR_F(stack_entry_t, 0);
11383         diagnostic_count  = 0;
11384         error_count       = 0;
11385         warning_count     = 0;
11386
11387         type_set_output(stderr);
11388         ast_set_output(stderr);
11389
11390         assert(unit == NULL);
11391         unit = allocate_ast_zero(sizeof(unit[0]));
11392
11393         assert(file_scope == NULL);
11394         file_scope = &unit->scope;
11395
11396         assert(current_scope == NULL);
11397         scope_push(&unit->scope);
11398
11399         create_gnu_builtins();
11400         if (c_mode & _MS)
11401                 create_microsoft_intrinsics();
11402 }
11403
11404 translation_unit_t *finish_parsing(void)
11405 {
11406         assert(current_scope == &unit->scope);
11407         scope_pop(NULL);
11408
11409         assert(file_scope == &unit->scope);
11410         check_unused_globals();
11411         file_scope = NULL;
11412
11413         DEL_ARR_F(environment_stack);
11414         DEL_ARR_F(label_stack);
11415
11416         translation_unit_t *result = unit;
11417         unit = NULL;
11418         return result;
11419 }
11420
11421 /* §6.9.2:2 and §6.9.2:5: At the end of the translation incomplete arrays
11422  * are given length one. */
11423 static void complete_incomplete_arrays(void)
11424 {
11425         size_t n = ARR_LEN(incomplete_arrays);
11426         for (size_t i = 0; i != n; ++i) {
11427                 declaration_t *const decl      = incomplete_arrays[i];
11428                 type_t        *const orig_type = decl->type;
11429                 type_t        *const type      = skip_typeref(orig_type);
11430
11431                 if (!is_type_incomplete(type))
11432                         continue;
11433
11434                 if (warning.other) {
11435                         warningf(&decl->base.source_position,
11436                                         "array '%#T' assumed to have one element",
11437                                         orig_type, decl->base.symbol);
11438                 }
11439
11440                 type_t *const new_type = duplicate_type(type);
11441                 new_type->array.size_constant     = true;
11442                 new_type->array.has_implicit_size = true;
11443                 new_type->array.size              = 1;
11444
11445                 type_t *const result = identify_new_type(new_type);
11446
11447                 decl->type = result;
11448         }
11449 }
11450
11451 void parse(void)
11452 {
11453         lookahead_bufpos = 0;
11454         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
11455                 next_token();
11456         }
11457         current_linkage   = c_mode & _CXX ? LINKAGE_CXX : LINKAGE_C;
11458         incomplete_arrays = NEW_ARR_F(declaration_t*, 0);
11459         parse_translation_unit();
11460         complete_incomplete_arrays();
11461         DEL_ARR_F(incomplete_arrays);
11462         incomplete_arrays = NULL;
11463 }
11464
11465 /**
11466  * create a builtin function.
11467  */
11468 static entity_t *create_builtin_function(builtin_kind_t kind, const char *name, type_t *function_type)
11469 {
11470         symbol_t *symbol = symbol_table_insert(name);
11471         entity_t *entity = allocate_entity_zero(ENTITY_FUNCTION);
11472         entity->declaration.storage_class          = STORAGE_CLASS_EXTERN;
11473         entity->declaration.declared_storage_class = STORAGE_CLASS_EXTERN;
11474         entity->declaration.type                   = function_type;
11475         entity->declaration.implicit               = true;
11476         entity->base.symbol                        = symbol;
11477         entity->base.source_position               = builtin_source_position;
11478
11479         entity->function.btk                       = kind;
11480
11481         record_entity(entity, /*is_definition=*/false);
11482         return entity;
11483 }
11484
11485
11486 /**
11487  * Create predefined gnu builtins.
11488  */
11489 static void create_gnu_builtins(void)
11490 {
11491 #define GNU_BUILTIN(a, b) create_builtin_function(bk_gnu_builtin_##a, "__builtin_" #a, b)
11492
11493         GNU_BUILTIN(alloca,         make_function_1_type(type_void_ptr, type_size_t));
11494         GNU_BUILTIN(huge_val,       make_function_0_type(type_double));
11495         GNU_BUILTIN(inf,            make_function_0_type(type_double));
11496         GNU_BUILTIN(inff,           make_function_0_type(type_float));
11497         GNU_BUILTIN(infl,           make_function_0_type(type_long_double));
11498         GNU_BUILTIN(nan,            make_function_1_type(type_double, type_char_ptr));
11499         GNU_BUILTIN(nanf,           make_function_1_type(type_float, type_char_ptr));
11500         GNU_BUILTIN(nanl,           make_function_1_type(type_long_double, type_char_ptr));
11501         GNU_BUILTIN(va_end,         make_function_1_type(type_void, type_valist));
11502         GNU_BUILTIN(expect,         make_function_2_type(type_long, type_long, type_long));
11503         GNU_BUILTIN(return_address, make_function_1_type(type_void_ptr, type_unsigned_int));
11504         GNU_BUILTIN(frame_address,  make_function_1_type(type_void_ptr, type_unsigned_int));
11505         GNU_BUILTIN(ffs,            make_function_1_type(type_int, type_unsigned_int));
11506         GNU_BUILTIN(clz,            make_function_1_type(type_int, type_unsigned_int));
11507         GNU_BUILTIN(ctz,            make_function_1_type(type_int, type_unsigned_int));
11508         GNU_BUILTIN(popcount,       make_function_1_type(type_int, type_unsigned_int));
11509         GNU_BUILTIN(parity,         make_function_1_type(type_int, type_unsigned_int));
11510         GNU_BUILTIN(prefetch,       make_function_1_type_variadic(type_float, type_void_ptr));
11511         GNU_BUILTIN(trap,           make_function_0_type_noreturn(type_void));
11512
11513 #undef GNU_BUILTIN
11514 }
11515
11516 /**
11517  * Create predefined MS intrinsics.
11518  */
11519 static void create_microsoft_intrinsics(void)
11520 {
11521 #define MS_BUILTIN(a, b) create_builtin_function(bk_ms##a, #a, b)
11522
11523         /* intrinsics for all architectures */
11524         MS_BUILTIN(_rotl,                  make_function_2_type(type_unsigned_int,   type_unsigned_int, type_int));
11525         MS_BUILTIN(_rotr,                  make_function_2_type(type_unsigned_int,   type_unsigned_int, type_int));
11526         MS_BUILTIN(_rotl64,                make_function_2_type(type_unsigned_int64, type_unsigned_int64, type_int));
11527         MS_BUILTIN(_rotr64,                make_function_2_type(type_unsigned_int64, type_unsigned_int64, type_int));
11528         MS_BUILTIN(_byteswap_ushort,       make_function_1_type(type_unsigned_short, type_unsigned_short));
11529         MS_BUILTIN(_byteswap_ulong,        make_function_1_type(type_unsigned_long,  type_unsigned_long));
11530         MS_BUILTIN(_byteswap_uint64,       make_function_1_type(type_unsigned_int64, type_unsigned_int64));
11531
11532         MS_BUILTIN(__debugbreak,            make_function_0_type(type_void));
11533         MS_BUILTIN(_ReturnAddress,          make_function_0_type(type_void_ptr));
11534         MS_BUILTIN(_AddressOfReturnAddress, make_function_0_type(type_void_ptr));
11535         MS_BUILTIN(__popcount,              make_function_1_type(type_unsigned_int, type_unsigned_int));
11536
11537         /* x86/x64 only */
11538         MS_BUILTIN(_enable,                make_function_0_type(type_void));
11539         MS_BUILTIN(_disable,               make_function_0_type(type_void));
11540         MS_BUILTIN(__inbyte,               make_function_1_type(type_unsigned_char, type_unsigned_short));
11541         MS_BUILTIN(__inword,               make_function_1_type(type_unsigned_short, type_unsigned_short));
11542         MS_BUILTIN(__indword,              make_function_1_type(type_unsigned_long, type_unsigned_short));
11543         MS_BUILTIN(__outbyte,              make_function_2_type(type_void, type_unsigned_short, type_unsigned_char));
11544         MS_BUILTIN(__outword,              make_function_2_type(type_void, type_unsigned_short, type_unsigned_short));
11545         MS_BUILTIN(__outdword,             make_function_2_type(type_void, type_unsigned_short, type_unsigned_long));
11546         MS_BUILTIN(__ud2,                  make_function_0_type_noreturn(type_void));
11547         MS_BUILTIN(_BitScanForward,        make_function_2_type(type_unsigned_char, type_unsigned_long_ptr, type_unsigned_long));
11548         MS_BUILTIN(_BitScanReverse,        make_function_2_type(type_unsigned_char, type_unsigned_long_ptr, type_unsigned_long));
11549         MS_BUILTIN(_InterlockedExchange,   make_function_2_type(type_long, type_long_ptr, type_long));
11550         MS_BUILTIN(_InterlockedExchange64, make_function_2_type(type_int64, type_int64_ptr, type_int64));
11551
11552         if (machine_size <= 32) {
11553                 MS_BUILTIN(__readeflags,           make_function_0_type(type_unsigned_int));
11554                 MS_BUILTIN(__writeeflags,          make_function_1_type(type_void, type_unsigned_int));
11555         } else {
11556                 MS_BUILTIN(__readeflags,           make_function_0_type(type_unsigned_int64));
11557                 MS_BUILTIN(__writeeflags,          make_function_1_type(type_void, type_unsigned_int64));
11558         }
11559
11560 #undef MS_BUILTIN
11561 }
11562
11563 /**
11564  * Initialize the parser.
11565  */
11566 void init_parser(void)
11567 {
11568         sym_anonymous = symbol_table_insert("<anonymous>");
11569
11570         if (c_mode & _MS) {
11571                 /* add predefined symbols for extended-decl-modifier */
11572                 sym_align         = symbol_table_insert("align");
11573                 sym_allocate      = symbol_table_insert("allocate");
11574                 sym_dllimport     = symbol_table_insert("dllimport");
11575                 sym_dllexport     = symbol_table_insert("dllexport");
11576                 sym_naked         = symbol_table_insert("naked");
11577                 sym_noinline      = symbol_table_insert("noinline");
11578                 sym_returns_twice = symbol_table_insert("returns_twice");
11579                 sym_noreturn      = symbol_table_insert("noreturn");
11580                 sym_nothrow       = symbol_table_insert("nothrow");
11581                 sym_novtable      = symbol_table_insert("novtable");
11582                 sym_property      = symbol_table_insert("property");
11583                 sym_get           = symbol_table_insert("get");
11584                 sym_put           = symbol_table_insert("put");
11585                 sym_selectany     = symbol_table_insert("selectany");
11586                 sym_thread        = symbol_table_insert("thread");
11587                 sym_uuid          = symbol_table_insert("uuid");
11588                 sym_deprecated    = symbol_table_insert("deprecated");
11589                 sym_restrict      = symbol_table_insert("restrict");
11590                 sym_noalias       = symbol_table_insert("noalias");
11591         }
11592         memset(token_anchor_set, 0, sizeof(token_anchor_set));
11593
11594         init_expression_parsers();
11595         obstack_init(&temp_obst);
11596
11597         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
11598         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
11599 }
11600
11601 /**
11602  * Terminate the parser.
11603  */
11604 void exit_parser(void)
11605 {
11606         obstack_free(&temp_obst, NULL);
11607 }