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 2
  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                 have_arguments; /**< True, if this attribute has arguments. */
  65         union {
  66                 size_t              value;
  67                 string_t            string;
  68                 atomic_type_kind_t  akind;
  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 /**
 102  * Capture a MS __base extension.
 103  */
 104 typedef struct based_spec_t {
 105         source_position_t  source_position;
 106         variable_t        *base_variable;
 107 } based_spec_t;
 108
 109 typedef entity_t* (*parsed_declaration_func) (entity_t *declaration, bool is_definition);
 110
 111 /** The current token. */
 112 static token_t              token;
 113 /** The lookahead ring-buffer. */
 114 static token_t              lookahead_buffer[MAX_LOOKAHEAD];
 115 /** Position of the next token in the lookahead buffer. */
 116 static int                  lookahead_bufpos;
 117 static stack_entry_t       *environment_stack = NULL;
 118 static stack_entry_t       *label_stack       = NULL;
 119 static scope_t             *file_scope        = NULL;
 120 static scope_t             *current_scope     = NULL;
 121 /** Point to the current function declaration if inside a function. */
 122 static function_t          *current_function  = NULL;
 123 static entity_t            *current_init_decl = NULL;
 124 static switch_statement_t  *current_switch    = NULL;
 125 static statement_t         *current_loop      = NULL;
 126 static statement_t         *current_parent    = NULL;
 127 static ms_try_statement_t  *current_try       = NULL;
 128 static linkage_kind_t       current_linkage   = LINKAGE_INVALID;
 129 static goto_statement_t    *goto_first        = NULL;
 130 static goto_statement_t   **goto_anchor       = NULL;
 131 static label_statement_t   *label_first       = NULL;
 132 static label_statement_t  **label_anchor      = NULL;
 133 /** current translation unit. */
 134 static translation_unit_t  *unit              = NULL;
 135 /** true if we are in a type property context (evaluation only for type. */
 136 static bool                 in_type_prop      = false;
 137 /** true in we are in a __extension__ context. */
 138 static bool                 in_gcc_extension  = false;
 139 static struct obstack       temp_obst;
 140 static entity_t            *anonymous_entity;
 141 static declaration_t      **incomplete_arrays;
 142
 143
 144 #define PUSH_PARENT(stmt)                          \
 145         statement_t *const prev_parent = current_parent; \
 146         ((void)(current_parent = (stmt)))
 147 #define POP_PARENT ((void)(current_parent = prev_parent))
 148
 149 /** special symbol used for anonymous entities. */
 150 static const symbol_t *sym_anonymous = NULL;
 151
 152 /* symbols for Microsoft extended-decl-modifier */
 153 static const symbol_t *sym_align         = NULL;
 154 static const symbol_t *sym_allocate      = NULL;
 155 static const symbol_t *sym_dllimport     = NULL;
 156 static const symbol_t *sym_dllexport     = NULL;
 157 static const symbol_t *sym_naked         = NULL;
 158 static const symbol_t *sym_noinline      = NULL;
 159 static const symbol_t *sym_returns_twice = NULL;
 160 static const symbol_t *sym_noreturn      = NULL;
 161 static const symbol_t *sym_nothrow       = NULL;
 162 static const symbol_t *sym_novtable      = NULL;
 163 static const symbol_t *sym_property      = NULL;
 164 static const symbol_t *sym_get           = NULL;
 165 static const symbol_t *sym_put           = NULL;
 166 static const symbol_t *sym_selectany     = NULL;
 167 static const symbol_t *sym_thread        = NULL;
 168 static const symbol_t *sym_uuid          = NULL;
 169 static const symbol_t *sym_deprecated    = NULL;
 170 static const symbol_t *sym_restrict      = NULL;
 171 static const symbol_t *sym_noalias       = NULL;
 172
 173 /** The token anchor set */
 174 static unsigned char token_anchor_set[T_LAST_TOKEN];
 175
 176 /** The current source position. */
 177 #define HERE (&token.source_position)
 178
 179 /** true if we are in GCC mode. */
 180 #define GNU_MODE ((c_mode & _GNUC) || in_gcc_extension)
 181
 182 static type_t *type_valist;
 183
 184 static statement_t *parse_compound_statement(bool inside_expression_statement);
 185 static statement_t *parse_statement(void);
 186
 187 static expression_t *parse_sub_expression(precedence_t);
 188 static expression_t *parse_expression(void);
 189 static type_t       *parse_typename(void);
 190 static void          parse_externals(void);
 191 static void          parse_external(void);
 192
 193 static void parse_compound_type_entries(compound_t *compound_declaration);
 194
 195 typedef enum declarator_flags_t {
 196         DECL_FLAGS_NONE             = 0,
 197         DECL_MAY_BE_ABSTRACT        = 1U << 0,
 198         DECL_CREATE_COMPOUND_MEMBER = 1U << 1,
 199         DECL_IS_PARAMETER           = 1U << 2
 200 } declarator_flags_t;
 201
 202 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
 203                                   declarator_flags_t flags);
 204
 205 static entity_t *record_entity(entity_t *entity, bool is_definition);
 206
 207 static void semantic_comparison(binary_expression_t *expression);
 208
 209 #define STORAGE_CLASSES       \
 210         STORAGE_CLASSES_NO_EXTERN \
 211         case T_extern:
 212
 213 #define STORAGE_CLASSES_NO_EXTERN \
 214         case T_typedef:         \
 215         case T_static:          \
 216         case T_auto:            \
 217         case T_register:        \
 218         case T___thread:
 219
 220 #define TYPE_QUALIFIERS     \
 221         case T_const:           \
 222         case T_restrict:        \
 223         case T_volatile:        \
 224         case T_inline:          \
 225         case T__forceinline:    \
 226         case T___attribute__:
 227
 228 #define COMPLEX_SPECIFIERS  \
 229         case T__Complex:
 230 #define IMAGINARY_SPECIFIERS \
 231         case T__Imaginary:
 232
 233 #define TYPE_SPECIFIERS       \
 234         case T__Bool:             \
 235         case T___builtin_va_list: \
 236         case T___typeof__:        \
 237         case T__declspec:         \
 238         case T_bool:              \
 239         case T_char:              \
 240         case T_double:            \
 241         case T_enum:              \
 242         case T_float:             \
 243         case T_int:               \
 244         case T_long:              \
 245         case T_short:             \
 246         case T_signed:            \
 247         case T_struct:            \
 248         case T_union:             \
 249         case T_unsigned:          \
 250         case T_void:              \
 251         case T_wchar_t:           \
 252         COMPLEX_SPECIFIERS        \
 253         IMAGINARY_SPECIFIERS
 254
 255 #define DECLARATION_START   \
 256         STORAGE_CLASSES         \
 257         TYPE_QUALIFIERS         \
 258         TYPE_SPECIFIERS
 259
 260 #define DECLARATION_START_NO_EXTERN \
 261         STORAGE_CLASSES_NO_EXTERN       \
 262         TYPE_QUALIFIERS                 \
 263         TYPE_SPECIFIERS
 264
 265 #define TYPENAME_START      \
 266         TYPE_QUALIFIERS         \
 267         TYPE_SPECIFIERS
 268
 269 #define EXPRESSION_START           \
 270         case '!':                        \
 271         case '&':                        \
 272         case '(':                        \
 273         case '*':                        \
 274         case '+':                        \
 275         case '-':                        \
 276         case '~':                        \
 277         case T_ANDAND:                   \
 278         case T_CHARACTER_CONSTANT:       \
 279         case T_FLOATINGPOINT:            \
 280         case T_INTEGER:                  \
 281         case T_MINUSMINUS:               \
 282         case T_PLUSPLUS:                 \
 283         case T_STRING_LITERAL:           \
 284         case T_WIDE_CHARACTER_CONSTANT:  \
 285         case T_WIDE_STRING_LITERAL:      \
 286         case T___FUNCDNAME__:            \
 287         case T___FUNCSIG__:              \
 288         case T___FUNCTION__:             \
 289         case T___PRETTY_FUNCTION__:      \
 290         case T___alignof__:              \
 291         case T___builtin_alloca:         \
 292         case T___builtin_classify_type:  \
 293         case T___builtin_constant_p:     \
 294         case T___builtin_expect:         \
 295         case T___builtin_huge_val:       \
 296         case T___builtin_inf:            \
 297         case T___builtin_inff:           \
 298         case T___builtin_infl:           \
 299         case T___builtin_isgreater:      \
 300         case T___builtin_isgreaterequal: \
 301         case T___builtin_isless:         \
 302         case T___builtin_islessequal:    \
 303         case T___builtin_islessgreater:  \
 304         case T___builtin_isunordered:    \
 305         case T___builtin_nan:            \
 306         case T___builtin_nanf:           \
 307         case T___builtin_nanl:           \
 308         case T___builtin_offsetof:       \
 309         case T___builtin_prefetch:       \
 310         case T___builtin_va_arg:         \
 311         case T___builtin_va_end:         \
 312         case T___builtin_va_start:       \
 313         case T___func__:                 \
 314         case T___noop:                   \
 315         case T__assume:                  \
 316         case T_delete:                   \
 317         case T_false:                    \
 318         case T_sizeof:                   \
 319         case T_throw:                    \
 320         case T_true:
 321
 322 /**
 323  * Allocate an AST node with given size and
 324  * initialize all fields with zero.
 325  */
 326 static void *allocate_ast_zero(size_t size)
 327 {
 328         void *res = allocate_ast(size);
 329         memset(res, 0, size);
 330         return res;
 331 }
 332
 333 /**
 334  * Returns the size of an entity node.
 335  *
 336  * @param kind  the entity kind
 337  */
 338 static size_t get_entity_struct_size(entity_kind_t kind)
 339 {
 340         static const size_t sizes[] = {
 341                 [ENTITY_VARIABLE]        = sizeof(variable_t),
 342                 [ENTITY_PARAMETER]       = sizeof(parameter_t),
 343                 [ENTITY_COMPOUND_MEMBER] = sizeof(compound_member_t),
 344                 [ENTITY_FUNCTION]        = sizeof(function_t),
 345                 [ENTITY_TYPEDEF]         = sizeof(typedef_t),
 346                 [ENTITY_STRUCT]          = sizeof(compound_t),
 347                 [ENTITY_UNION]           = sizeof(compound_t),
 348                 [ENTITY_ENUM]            = sizeof(enum_t),
 349                 [ENTITY_ENUM_VALUE]      = sizeof(enum_value_t),
 350                 [ENTITY_LABEL]           = sizeof(label_t),
 351                 [ENTITY_LOCAL_LABEL]     = sizeof(label_t),
 352                 [ENTITY_NAMESPACE]       = sizeof(namespace_t)
 353         };
 354         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 355         assert(sizes[kind] != 0);
 356         return sizes[kind];
 357 }
 358
 359 /**
 360  * Allocate an entity of given kind and initialize all
 361  * fields with zero.
 362  */
 363 static entity_t *allocate_entity_zero(entity_kind_t kind)
 364 {
 365         size_t    size   = get_entity_struct_size(kind);
 366         entity_t *entity = allocate_ast_zero(size);
 367         entity->kind     = kind;
 368         return entity;
 369 }
 370
 371 /**
 372  * Returns the size of a statement node.
 373  *
 374  * @param kind  the statement kind
 375  */
 376 static size_t get_statement_struct_size(statement_kind_t kind)
 377 {
 378         static const size_t sizes[] = {
 379                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 380                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 381                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 382                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 383                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 384                 [STATEMENT_IF]          = sizeof(if_statement_t),
 385                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 386                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 387                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 388                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 389                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 390                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 391                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 392                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 393                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 394                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 395                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 396                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 397                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 398         };
 399         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 400         assert(sizes[kind] != 0);
 401         return sizes[kind];
 402 }
 403
 404 /**
 405  * Returns the size of an expression node.
 406  *
 407  * @param kind  the expression kind
 408  */
 409 static size_t get_expression_struct_size(expression_kind_t kind)
 410 {
 411         static const size_t sizes[] = {
 412                 [EXPR_INVALID]                 = sizeof(expression_base_t),
 413                 [EXPR_REFERENCE]               = sizeof(reference_expression_t),
 414                 [EXPR_REFERENCE_ENUM_VALUE]    = sizeof(reference_expression_t),
 415                 [EXPR_CONST]                   = sizeof(const_expression_t),
 416                 [EXPR_CHARACTER_CONSTANT]      = sizeof(const_expression_t),
 417                 [EXPR_WIDE_CHARACTER_CONSTANT] = sizeof(const_expression_t),
 418                 [EXPR_STRING_LITERAL]          = sizeof(string_literal_expression_t),
 419                 [EXPR_WIDE_STRING_LITERAL]     = sizeof(wide_string_literal_expression_t),
 420                 [EXPR_COMPOUND_LITERAL]        = sizeof(compound_literal_expression_t),
 421                 [EXPR_CALL]                    = sizeof(call_expression_t),
 422                 [EXPR_UNARY_FIRST]             = sizeof(unary_expression_t),
 423                 [EXPR_BINARY_FIRST]            = sizeof(binary_expression_t),
 424                 [EXPR_CONDITIONAL]             = sizeof(conditional_expression_t),
 425                 [EXPR_SELECT]                  = sizeof(select_expression_t),
 426                 [EXPR_ARRAY_ACCESS]            = sizeof(array_access_expression_t),
 427                 [EXPR_SIZEOF]                  = sizeof(typeprop_expression_t),
 428                 [EXPR_ALIGNOF]                 = sizeof(typeprop_expression_t),
 429                 [EXPR_CLASSIFY_TYPE]           = sizeof(classify_type_expression_t),
 430                 [EXPR_FUNCNAME]                = sizeof(funcname_expression_t),
 431                 [EXPR_BUILTIN_SYMBOL]          = sizeof(builtin_symbol_expression_t),
 432                 [EXPR_BUILTIN_CONSTANT_P]      = sizeof(builtin_constant_expression_t),
 433                 [EXPR_BUILTIN_PREFETCH]        = sizeof(builtin_prefetch_expression_t),
 434                 [EXPR_OFFSETOF]                = sizeof(offsetof_expression_t),
 435                 [EXPR_VA_START]                = sizeof(va_start_expression_t),
 436                 [EXPR_VA_ARG]                  = sizeof(va_arg_expression_t),
 437                 [EXPR_STATEMENT]               = sizeof(statement_expression_t),
 438                 [EXPR_LABEL_ADDRESS]           = sizeof(label_address_expression_t),
 439         };
 440         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 441                 return sizes[EXPR_UNARY_FIRST];
 442         }
 443         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 444                 return sizes[EXPR_BINARY_FIRST];
 445         }
 446         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 447         assert(sizes[kind] != 0);
 448         return sizes[kind];
 449 }
 450
 451 /**
 452  * Allocate a statement node of given kind and initialize all
 453  * fields with zero. Sets its source position to the position
 454  * of the current token.
 455  */
 456 static statement_t *allocate_statement_zero(statement_kind_t kind)
 457 {
 458         size_t       size = get_statement_struct_size(kind);
 459         statement_t *res  = allocate_ast_zero(size);
 460
 461         res->base.kind            = kind;
 462         res->base.parent          = current_parent;
 463         res->base.source_position = token.source_position;
 464         return res;
 465 }
 466
 467 /**
 468  * Allocate an expression node of given kind and initialize all
 469  * fields with zero.
 470  */
 471 static expression_t *allocate_expression_zero(expression_kind_t kind)
 472 {
 473         size_t        size = get_expression_struct_size(kind);
 474         expression_t *res  = allocate_ast_zero(size);
 475
 476         res->base.kind            = kind;
 477         res->base.type            = type_error_type;
 478         res->base.source_position = token.source_position;
 479         return res;
 480 }
 481
 482 /**
 483  * Creates a new invalid expression at the source position
 484  * of the current token.
 485  */
 486 static expression_t *create_invalid_expression(void)
 487 {
 488         return allocate_expression_zero(EXPR_INVALID);
 489 }
 490
 491 /**
 492  * Creates a new invalid statement.
 493  */
 494 static statement_t *create_invalid_statement(void)
 495 {
 496         return allocate_statement_zero(STATEMENT_INVALID);
 497 }
 498
 499 /**
 500  * Allocate a new empty statement.
 501  */
 502 static statement_t *create_empty_statement(void)
 503 {
 504         return allocate_statement_zero(STATEMENT_EMPTY);
 505 }
 506
 507 /**
 508  * Returns the size of a type node.
 509  *
 510  * @param kind  the type kind
 511  */
 512 static size_t get_type_struct_size(type_kind_t kind)
 513 {
 514         static const size_t sizes[] = {
 515                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
 516                 [TYPE_COMPLEX]         = sizeof(complex_type_t),
 517                 [TYPE_IMAGINARY]       = sizeof(imaginary_type_t),
 518                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
 519                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
 520                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
 521                 [TYPE_ENUM]            = sizeof(enum_type_t),
 522                 [TYPE_FUNCTION]        = sizeof(function_type_t),
 523                 [TYPE_POINTER]         = sizeof(pointer_type_t),
 524                 [TYPE_ARRAY]           = sizeof(array_type_t),
 525                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
 526                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
 527                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
 528         };
 529         assert(sizeof(sizes) / sizeof(sizes[0]) == (int) TYPE_TYPEOF + 1);
 530         assert(kind <= TYPE_TYPEOF);
 531         assert(sizes[kind] != 0);
 532         return sizes[kind];
 533 }
 534
 535 /**
 536  * Allocate a type node of given kind and initialize all
 537  * fields with zero.
 538  *
 539  * @param kind             type kind to allocate
 540  */
 541 static type_t *allocate_type_zero(type_kind_t kind)
 542 {
 543         size_t  size = get_type_struct_size(kind);
 544         type_t *res  = obstack_alloc(type_obst, size);
 545         memset(res, 0, size);
 546         res->base.kind = kind;
 547
 548         return res;
 549 }
 550
 551 /**
 552  * Returns the size of an initializer node.
 553  *
 554  * @param kind  the initializer kind
 555  */
 556 static size_t get_initializer_size(initializer_kind_t kind)
 557 {
 558         static const size_t sizes[] = {
 559                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 560                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 561                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 562                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 563                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 564         };
 565         assert(kind < sizeof(sizes) / sizeof(*sizes));
 566         assert(sizes[kind] != 0);
 567         return sizes[kind];
 568 }
 569
 570 /**
 571  * Allocate an initializer node of given kind and initialize all
 572  * fields with zero.
 573  */
 574 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 575 {
 576         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 577         result->kind          = kind;
 578
 579         return result;
 580 }
 581
 582 /**
 583  * Free a type from the type obstack.
 584  */
 585 static void free_type(void *type)
 586 {
 587         obstack_free(type_obst, type);
 588 }
 589
 590 /**
 591  * Returns the index of the top element of the environment stack.
 592  */
 593 static size_t environment_top(void)
 594 {
 595         return ARR_LEN(environment_stack);
 596 }
 597
 598 /**
 599  * Returns the index of the top element of the global label stack.
 600  */
 601 static size_t label_top(void)
 602 {
 603         return ARR_LEN(label_stack);
 604 }
 605
 606 /**
 607  * Return the next token.
 608  */
 609 static inline void next_token(void)
 610 {
 611         token                              = lookahead_buffer[lookahead_bufpos];
 612         lookahead_buffer[lookahead_bufpos] = lexer_token;
 613         lexer_next_token();
 614
 615         lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
 616
 617 #ifdef PRINT_TOKENS
 618         print_token(stderr, &token);
 619         fprintf(stderr, "\n");
 620 #endif
 621 }
 622
 623 /**
 624  * Return the next token with a given lookahead.
 625  */
 626 static inline const token_t *look_ahead(int num)
 627 {
 628         assert(num > 0 && num <= MAX_LOOKAHEAD);
 629         int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
 630         return &lookahead_buffer[pos];
 631 }
 632
 633 /**
 634  * Adds a token type to the token type anchor set (a multi-set).
 635  */
 636 static void add_anchor_token(int token_type)
 637 {
 638         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 639         ++token_anchor_set[token_type];
 640 }
 641
 642 /**
 643  * Set the number of tokens types of the given type
 644  * to zero and return the old count.
 645  */
 646 static int save_and_reset_anchor_state(int token_type)
 647 {
 648         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 649         int count = token_anchor_set[token_type];
 650         token_anchor_set[token_type] = 0;
 651         return count;
 652 }
 653
 654 /**
 655  * Restore the number of token types to the given count.
 656  */
 657 static void restore_anchor_state(int token_type, int count)
 658 {
 659         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 660         token_anchor_set[token_type] = count;
 661 }
 662
 663 /**
 664  * Remove a token type from the token type anchor set (a multi-set).
 665  */
 666 static void rem_anchor_token(int token_type)
 667 {
 668         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 669         assert(token_anchor_set[token_type] != 0);
 670         --token_anchor_set[token_type];
 671 }
 672
 673 /**
 674  * Return true if the token type of the current token is
 675  * in the anchor set.
 676  */
 677 static bool at_anchor(void)
 678 {
 679         if (token.type < 0)
 680                 return false;
 681         return token_anchor_set[token.type];
 682 }
 683
 684 /**
 685  * Eat tokens until a matching token type is found.
 686  */
 687 static void eat_until_matching_token(int type)
 688 {
 689         int end_token;
 690         switch (type) {
 691                 case '(': end_token = ')';  break;
 692                 case '{': end_token = '}';  break;
 693                 case '[': end_token = ']';  break;
 694                 default:  end_token = type; break;
 695         }
 696
 697         unsigned parenthesis_count = 0;
 698         unsigned brace_count       = 0;
 699         unsigned bracket_count     = 0;
 700         while (token.type        != end_token ||
 701                parenthesis_count != 0         ||
 702                brace_count       != 0         ||
 703                bracket_count     != 0) {
 704                 switch (token.type) {
 705                 case T_EOF: return;
 706                 case '(': ++parenthesis_count; break;
 707                 case '{': ++brace_count;       break;
 708                 case '[': ++bracket_count;     break;
 709
 710                 case ')':
 711                         if (parenthesis_count > 0)
 712                                 --parenthesis_count;
 713                         goto check_stop;
 714
 715                 case '}':
 716                         if (brace_count > 0)
 717                                 --brace_count;
 718                         goto check_stop;
 719
 720                 case ']':
 721                         if (bracket_count > 0)
 722                                 --bracket_count;
 723 check_stop:
 724                         if (token.type        == end_token &&
 725                             parenthesis_count == 0         &&
 726                             brace_count       == 0         &&
 727                             bracket_count     == 0)
 728                                 return;
 729                         break;
 730
 731                 default:
 732                         break;
 733                 }
 734                 next_token();
 735         }
 736 }
 737
 738 /**
 739  * Eat input tokens until an anchor is found.
 740  */
 741 static void eat_until_anchor(void)
 742 {
 743         while (token_anchor_set[token.type] == 0) {
 744                 if (token.type == '(' || token.type == '{' || token.type == '[')
 745                         eat_until_matching_token(token.type);
 746                 next_token();
 747         }
 748 }
 749
 750 /**
 751  * Eat a whole block from input tokens.
 752  */
 753 static void eat_block(void)
 754 {
 755         eat_until_matching_token('{');
 756         if (token.type == '}')
 757                 next_token();
 758 }
 759
 760 #define eat(token_type)  do { assert(token.type == (token_type)); next_token(); } while (0)
 761
 762 /**
 763  * Report a parse error because an expected token was not found.
 764  */
 765 static
 766 #if defined __GNUC__ && __GNUC__ >= 4
 767 __attribute__((sentinel))
 768 #endif
 769 void parse_error_expected(const char *message, ...)
 770 {
 771         if (message != NULL) {
 772                 errorf(HERE, "%s", message);
 773         }
 774         va_list ap;
 775         va_start(ap, message);
 776         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 777         va_end(ap);
 778 }
 779
 780 /**
 781  * Report an incompatible type.
 782  */
 783 static void type_error_incompatible(const char *msg,
 784                 const source_position_t *source_position, type_t *type1, type_t *type2)
 785 {
 786         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 787                msg, type1, type2);
 788 }
 789
 790 /**
 791  * Expect the current token is the expected token.
 792  * If not, generate an error, eat the current statement,
 793  * and goto the end_error label.
 794  */
 795 #define expect(expected, error_label)                     \
 796         do {                                                  \
 797                 if (UNLIKELY(token.type != (expected))) {         \
 798                         parse_error_expected(NULL, (expected), NULL); \
 799                         add_anchor_token(expected);                   \
 800                         eat_until_anchor();                           \
 801                         if (token.type == expected)                   \
 802                                 next_token();                             \
 803                         rem_anchor_token(expected);                   \
 804                         goto error_label;                             \
 805                 }                                                 \
 806                 next_token();                                     \
 807         } while (0)
 808
 809 /**
 810  * Push a given scope on the scope stack and make it the
 811  * current scope
 812  */
 813 static scope_t *scope_push(scope_t *new_scope)
 814 {
 815         if (current_scope != NULL) {
 816                 new_scope->depth = current_scope->depth + 1;
 817         }
 818
 819         scope_t *old_scope = current_scope;
 820         current_scope      = new_scope;
 821         return old_scope;
 822 }
 823
 824 /**
 825  * Pop the current scope from the scope stack.
 826  */
 827 static void scope_pop(scope_t *old_scope)
 828 {
 829         current_scope = old_scope;
 830 }
 831
 832 /**
 833  * Search an entity by its symbol in a given namespace.
 834  */
 835 static entity_t *get_entity(const symbol_t *const symbol,
 836                             namespace_tag_t namespc)
 837 {
 838         entity_t *entity = symbol->entity;
 839         for (; entity != NULL; entity = entity->base.symbol_next) {
 840                 if (entity->base.namespc == namespc)
 841                         return entity;
 842         }
 843
 844         return NULL;
 845 }
 846
 847 /**
 848  * pushs an entity on the environment stack and links the corresponding symbol
 849  * it.
 850  */
 851 static void stack_push(stack_entry_t **stack_ptr, entity_t *entity)
 852 {
 853         symbol_t           *symbol  = entity->base.symbol;
 854         entity_namespace_t  namespc = entity->base.namespc;
 855         assert(namespc != NAMESPACE_INVALID);
 856
 857         /* replace/add entity into entity list of the symbol */
 858         entity_t **anchor;
 859         entity_t  *iter;
 860         for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 861                 iter = *anchor;
 862                 if (iter == NULL)
 863                         break;
 864
 865                 /* replace an entry? */
 866                 if (iter->base.namespc == namespc) {
 867                         entity->base.symbol_next = iter->base.symbol_next;
 868                         break;
 869                 }
 870         }
 871         *anchor = entity;
 872
 873         /* remember old declaration */
 874         stack_entry_t entry;
 875         entry.symbol     = symbol;
 876         entry.old_entity = iter;
 877         entry.namespc    = namespc;
 878         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 879 }
 880
 881 /**
 882  * Push an entity on the environment stack.
 883  */
 884 static void environment_push(entity_t *entity)
 885 {
 886         assert(entity->base.source_position.input_name != NULL);
 887         assert(entity->base.parent_scope != NULL);
 888         stack_push(&environment_stack, entity);
 889 }
 890
 891 /**
 892  * Push a declaration on the global label stack.
 893  *
 894  * @param declaration  the declaration
 895  */
 896 static void label_push(entity_t *label)
 897 {
 898         /* we abuse the parameters scope as parent for the labels */
 899         label->base.parent_scope = &current_function->parameters;
 900         stack_push(&label_stack, label);
 901 }
 902
 903 /**
 904  * pops symbols from the environment stack until @p new_top is the top element
 905  */
 906 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 907 {
 908         stack_entry_t *stack = *stack_ptr;
 909         size_t         top   = ARR_LEN(stack);
 910         size_t         i;
 911
 912         assert(new_top <= top);
 913         if (new_top == top)
 914                 return;
 915
 916         for (i = top; i > new_top; --i) {
 917                 stack_entry_t *entry = &stack[i - 1];
 918
 919                 entity_t           *old_entity = entry->old_entity;
 920                 symbol_t           *symbol     = entry->symbol;
 921                 entity_namespace_t  namespc    = entry->namespc;
 922
 923                 /* replace with old_entity/remove */
 924                 entity_t **anchor;
 925                 entity_t  *iter;
 926                 for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 927                         iter = *anchor;
 928                         assert(iter != NULL);
 929                         /* replace an entry? */
 930                         if (iter->base.namespc == namespc)
 931                                 break;
 932                 }
 933
 934                 /* restore definition from outer scopes (if there was one) */
 935                 if (old_entity != NULL) {
 936                         old_entity->base.symbol_next = iter->base.symbol_next;
 937                         *anchor                      = old_entity;
 938                 } else {
 939                         /* remove entry from list */
 940                         *anchor = iter->base.symbol_next;
 941                 }
 942         }
 943
 944         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
 945 }
 946
 947 /**
 948  * Pop all entries from the environment stack until the new_top
 949  * is reached.
 950  *
 951  * @param new_top  the new stack top
 952  */
 953 static void environment_pop_to(size_t new_top)
 954 {
 955         stack_pop_to(&environment_stack, new_top);
 956 }
 957
 958 /**
 959  * Pop all entries from the global label stack until the new_top
 960  * is reached.
 961  *
 962  * @param new_top  the new stack top
 963  */
 964 static void label_pop_to(size_t new_top)
 965 {
 966         stack_pop_to(&label_stack, new_top);
 967 }
 968
 969 static int get_akind_rank(atomic_type_kind_t akind)
 970 {
 971         return (int) akind;
 972 }
 973
 974 /**
 975  * Return the type rank for an atomic type.
 976  */
 977 static int get_rank(const type_t *type)
 978 {
 979         assert(!is_typeref(type));
 980         /* The C-standard allows promoting enums to int or unsigned int (see § 7.2.2
 981          * and esp. footnote 108). However we can't fold constants (yet), so we
 982          * can't decide whether unsigned int is possible, while int always works.
 983          * (unsigned int would be preferable when possible... for stuff like
 984          *  struct { enum { ... } bla : 4; } ) */
 985         if (type->kind == TYPE_ENUM)
 986                 return get_akind_rank(ATOMIC_TYPE_INT);
 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                 expression = expression->unary.value;
1037         }
1038
1039         /* TODO: not correct yet, should be any constant integer expression
1040          * which evaluates to 0 */
1041         if (expression->kind != EXPR_CONST)
1042                 return false;
1043
1044         type_t *const type = skip_typeref(expression->base.type);
1045         if (!is_type_integer(type))
1046                 return false;
1047
1048         return expression->conste.v.int_value == 0;
1049 }
1050
1051 /**
1052  * Create an implicit cast expression.
1053  *
1054  * @param expression  the expression to cast
1055  * @param dest_type   the destination type
1056  */
1057 static expression_t *create_implicit_cast(expression_t *expression,
1058                                           type_t *dest_type)
1059 {
1060         type_t *const source_type = expression->base.type;
1061
1062         if (source_type == dest_type)
1063                 return expression;
1064
1065         return create_cast_expression(expression, dest_type);
1066 }
1067
1068 typedef enum assign_error_t {
1069         ASSIGN_SUCCESS,
1070         ASSIGN_ERROR_INCOMPATIBLE,
1071         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
1072         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
1073         ASSIGN_WARNING_POINTER_FROM_INT,
1074         ASSIGN_WARNING_INT_FROM_POINTER
1075 } assign_error_t;
1076
1077 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
1078                                 const expression_t *const right,
1079                                 const char *context,
1080                                 const source_position_t *source_position)
1081 {
1082         type_t *const orig_type_right = right->base.type;
1083         type_t *const type_left       = skip_typeref(orig_type_left);
1084         type_t *const type_right      = skip_typeref(orig_type_right);
1085
1086         switch (error) {
1087         case ASSIGN_SUCCESS:
1088                 return;
1089         case ASSIGN_ERROR_INCOMPATIBLE:
1090                 errorf(source_position,
1091                        "destination type '%T' in %s is incompatible with type '%T'",
1092                        orig_type_left, context, orig_type_right);
1093                 return;
1094
1095         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
1096                 if (warning.other) {
1097                         type_t *points_to_left  = skip_typeref(type_left->pointer.points_to);
1098                         type_t *points_to_right = skip_typeref(type_right->pointer.points_to);
1099
1100                         /* the left type has all qualifiers from the right type */
1101                         unsigned missing_qualifiers
1102                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1103                         warningf(source_position,
1104                                         "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
1105                                         orig_type_left, context, orig_type_right, missing_qualifiers);
1106                 }
1107                 return;
1108         }
1109
1110         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
1111                 if (warning.other) {
1112                         warningf(source_position,
1113                                         "destination type '%T' in %s is incompatible with '%E' of type '%T'",
1114                                         orig_type_left, context, right, orig_type_right);
1115                 }
1116                 return;
1117
1118         case ASSIGN_WARNING_POINTER_FROM_INT:
1119                 if (warning.other) {
1120                         warningf(source_position,
1121                                         "%s makes pointer '%T' from integer '%T' without a cast",
1122                                         context, orig_type_left, orig_type_right);
1123                 }
1124                 return;
1125
1126         case ASSIGN_WARNING_INT_FROM_POINTER:
1127                 if (warning.other) {
1128                         warningf(source_position,
1129                                         "%s makes integer '%T' from pointer '%T' without a cast",
1130                                         context, orig_type_left, orig_type_right);
1131                 }
1132                 return;
1133
1134         default:
1135                 panic("invalid error value");
1136         }
1137 }
1138
1139 /** Implements the rules from § 6.5.16.1 */
1140 static assign_error_t semantic_assign(type_t *orig_type_left,
1141                                       const expression_t *const right)
1142 {
1143         type_t *const orig_type_right = right->base.type;
1144         type_t *const type_left       = skip_typeref(orig_type_left);
1145         type_t *const type_right      = skip_typeref(orig_type_right);
1146
1147         if (is_type_pointer(type_left)) {
1148                 if (is_null_pointer_constant(right)) {
1149                         return ASSIGN_SUCCESS;
1150                 } else if (is_type_pointer(type_right)) {
1151                         type_t *points_to_left
1152                                 = skip_typeref(type_left->pointer.points_to);
1153                         type_t *points_to_right
1154                                 = skip_typeref(type_right->pointer.points_to);
1155                         assign_error_t res = ASSIGN_SUCCESS;
1156
1157                         /* the left type has all qualifiers from the right type */
1158                         unsigned missing_qualifiers
1159                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1160                         if (missing_qualifiers != 0) {
1161                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1162                         }
1163
1164                         points_to_left  = get_unqualified_type(points_to_left);
1165                         points_to_right = get_unqualified_type(points_to_right);
1166
1167                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID))
1168                                 return res;
1169
1170                         if (is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1171                                 /* ISO/IEC 14882:1998(E) §C.1.2:6 */
1172                                 return c_mode & _CXX ? ASSIGN_ERROR_INCOMPATIBLE : res;
1173                         }
1174
1175                         if (!types_compatible(points_to_left, points_to_right)) {
1176                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1177                         }
1178
1179                         return res;
1180                 } else if (is_type_integer(type_right)) {
1181                         return ASSIGN_WARNING_POINTER_FROM_INT;
1182                 }
1183         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1184             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1185                 && is_type_pointer(type_right))) {
1186                 return ASSIGN_SUCCESS;
1187         } else if ((is_type_compound(type_left)  && is_type_compound(type_right))
1188                         || (is_type_builtin(type_left) && is_type_builtin(type_right))) {
1189                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1190                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1191                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1192                         return ASSIGN_SUCCESS;
1193                 }
1194         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1195                 return ASSIGN_WARNING_INT_FROM_POINTER;
1196         }
1197
1198         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1199                 return ASSIGN_SUCCESS;
1200
1201         return ASSIGN_ERROR_INCOMPATIBLE;
1202 }
1203
1204 static expression_t *parse_constant_expression(void)
1205 {
1206         expression_t *result = parse_sub_expression(PREC_CONDITIONAL);
1207
1208         if (!is_constant_expression(result)) {
1209                 errorf(&result->base.source_position,
1210                        "expression '%E' is not constant", result);
1211         }
1212
1213         return result;
1214 }
1215
1216 static expression_t *parse_assignment_expression(void)
1217 {
1218         return parse_sub_expression(PREC_ASSIGNMENT);
1219 }
1220
1221 static string_t parse_string_literals(void)
1222 {
1223         assert(token.type == T_STRING_LITERAL);
1224         string_t result = token.v.string;
1225
1226         next_token();
1227
1228         while (token.type == T_STRING_LITERAL) {
1229                 result = concat_strings(&result, &token.v.string);
1230                 next_token();
1231         }
1232
1233         return result;
1234 }
1235
1236 static const char *const gnu_attribute_names[GNU_AK_LAST] = {
1237         [GNU_AK_CONST]                  = "const",
1238         [GNU_AK_VOLATILE]               = "volatile",
1239         [GNU_AK_CDECL]                  = "cdecl",
1240         [GNU_AK_STDCALL]                = "stdcall",
1241         [GNU_AK_FASTCALL]               = "fastcall",
1242         [GNU_AK_DEPRECATED]             = "deprecated",
1243         [GNU_AK_NOINLINE]               = "noinline",
1244         [GNU_AK_RETURNS_TWICE]          = "returns_twice",
1245         [GNU_AK_NORETURN]               = "noreturn",
1246         [GNU_AK_NAKED]                  = "naked",
1247         [GNU_AK_PURE]                   = "pure",
1248         [GNU_AK_ALWAYS_INLINE]          = "always_inline",
1249         [GNU_AK_MALLOC]                 = "malloc",
1250         [GNU_AK_WEAK]                   = "weak",
1251         [GNU_AK_CONSTRUCTOR]            = "constructor",
1252         [GNU_AK_DESTRUCTOR]             = "destructor",
1253         [GNU_AK_NOTHROW]                = "nothrow",
1254         [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
1255         [GNU_AK_COMMON]                 = "common",
1256         [GNU_AK_NOCOMMON]               = "nocommon",
1257         [GNU_AK_PACKED]                 = "packed",
1258         [GNU_AK_SHARED]                 = "shared",
1259         [GNU_AK_NOTSHARED]              = "notshared",
1260         [GNU_AK_USED]                   = "used",
1261         [GNU_AK_UNUSED]                 = "unused",
1262         [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
1263         [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
1264         [GNU_AK_LONGCALL]               = "longcall",
1265         [GNU_AK_SHORTCALL]              = "shortcall",
1266         [GNU_AK_LONG_CALL]              = "long_call",
1267         [GNU_AK_SHORT_CALL]             = "short_call",
1268         [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
1269         [GNU_AK_INTERRUPT]              = "interrupt",
1270         [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
1271         [GNU_AK_NMI_HANDLER]            = "nmi_handler",
1272         [GNU_AK_NESTING]                = "nesting",
1273         [GNU_AK_NEAR]                   = "near",
1274         [GNU_AK_FAR]                    = "far",
1275         [GNU_AK_SIGNAL]                 = "signal",
1276         [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
1277         [GNU_AK_TINY_DATA]              = "tiny_data",
1278         [GNU_AK_SAVEALL]                = "saveall",
1279         [GNU_AK_FLATTEN]                = "flatten",
1280         [GNU_AK_SSEREGPARM]             = "sseregparm",
1281         [GNU_AK_EXTERNALLY_VISIBLE]     = "externally_visible",
1282         [GNU_AK_RETURN_TWICE]           = "return_twice",
1283         [GNU_AK_MAY_ALIAS]              = "may_alias",
1284         [GNU_AK_MS_STRUCT]              = "ms_struct",
1285         [GNU_AK_GCC_STRUCT]             = "gcc_struct",
1286         [GNU_AK_DLLIMPORT]              = "dllimport",
1287         [GNU_AK_DLLEXPORT]              = "dllexport",
1288         [GNU_AK_ALIGNED]                = "aligned",
1289         [GNU_AK_ALIAS]                  = "alias",
1290         [GNU_AK_SECTION]                = "section",
1291         [GNU_AK_FORMAT]                 = "format",
1292         [GNU_AK_FORMAT_ARG]             = "format_arg",
1293         [GNU_AK_WEAKREF]                = "weakref",
1294         [GNU_AK_NONNULL]                = "nonnull",
1295         [GNU_AK_TLS_MODEL]              = "tls_model",
1296         [GNU_AK_VISIBILITY]             = "visibility",
1297         [GNU_AK_REGPARM]                = "regparm",
1298         [GNU_AK_MODE]                   = "mode",
1299         [GNU_AK_MODEL]                  = "model",
1300         [GNU_AK_TRAP_EXIT]              = "trap_exit",
1301         [GNU_AK_SP_SWITCH]              = "sp_switch",
1302         [GNU_AK_SENTINEL]               = "sentinel"
1303 };
1304
1305 /**
1306  * compare two string, ignoring double underscores on the second.
1307  */
1308 static int strcmp_underscore(const char *s1, const char *s2)
1309 {
1310         if (s2[0] == '_' && s2[1] == '_') {
1311                 size_t len2 = strlen(s2);
1312                 size_t len1 = strlen(s1);
1313                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1314                         return strncmp(s1, s2+2, len2-4);
1315                 }
1316         }
1317
1318         return strcmp(s1, s2);
1319 }
1320
1321 /**
1322  * Allocate a new gnu temporal attribute of given kind.
1323  */
1324 static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
1325 {
1326         gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
1327         attribute->kind            = kind;
1328         attribute->next            = NULL;
1329         attribute->invalid         = false;
1330         attribute->have_arguments  = false;
1331
1332         return attribute;
1333 }
1334
1335 /**
1336  * Parse one constant expression argument of the given attribute.
1337  */
1338 static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
1339 {
1340         expression_t *expression;
1341         add_anchor_token(')');
1342         expression = parse_constant_expression();
1343         rem_anchor_token(')');
1344         expect(')', end_error);
1345         attribute->u.argument = fold_constant(expression);
1346         return;
1347 end_error:
1348         attribute->invalid = true;
1349 }
1350
1351 /**
1352  * Parse a list of constant expressions arguments of the given attribute.
1353  */
1354 static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
1355 {
1356         argument_list_t **list = &attribute->u.arguments;
1357         argument_list_t  *entry;
1358         expression_t     *expression;
1359         add_anchor_token(')');
1360         add_anchor_token(',');
1361         while (true) {
1362                 expression = parse_constant_expression();
1363                 entry = obstack_alloc(&temp_obst, sizeof(entry));
1364                 entry->argument = fold_constant(expression);
1365                 entry->next     = NULL;
1366                 *list = entry;
1367                 list = &entry->next;
1368                 if (token.type != ',')
1369                         break;
1370                 next_token();
1371         }
1372         rem_anchor_token(',');
1373         rem_anchor_token(')');
1374         expect(')', end_error);
1375         return;
1376 end_error:
1377         attribute->invalid = true;
1378 }
1379
1380 /**
1381  * Parse one string literal argument of the given attribute.
1382  */
1383 static void parse_gnu_attribute_string_arg(gnu_attribute_t *attribute,
1384                                            string_t *string)
1385 {
1386         add_anchor_token('(');
1387         if (token.type != T_STRING_LITERAL) {
1388                 parse_error_expected("while parsing attribute directive",
1389                                      T_STRING_LITERAL, NULL);
1390                 goto end_error;
1391         }
1392         *string = parse_string_literals();
1393         rem_anchor_token('(');
1394         expect(')', end_error);
1395         return;
1396 end_error:
1397         attribute->invalid = true;
1398 }
1399
1400 /**
1401  * Parse one tls model of the given attribute.
1402  */
1403 static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
1404 {
1405         static const char *const tls_models[] = {
1406                 "global-dynamic",
1407                 "local-dynamic",
1408                 "initial-exec",
1409                 "local-exec"
1410         };
1411         string_t string = { NULL, 0 };
1412         parse_gnu_attribute_string_arg(attribute, &string);
1413         if (string.begin != NULL) {
1414                 for (size_t i = 0; i < 4; ++i) {
1415                         if (strcmp(tls_models[i], string.begin) == 0) {
1416                                 attribute->u.value = i;
1417                                 return;
1418                         }
1419                 }
1420                 errorf(HERE, "'%s' is an unrecognized tls model", string.begin);
1421         }
1422         attribute->invalid = true;
1423 }
1424
1425 /**
1426  * Parse one tls model of the given attribute.
1427  */
1428 static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
1429 {
1430         static const char *const visibilities[] = {
1431                 "default",
1432                 "protected",
1433                 "hidden",
1434                 "internal"
1435         };
1436         string_t string = { NULL, 0 };
1437         parse_gnu_attribute_string_arg(attribute, &string);
1438         if (string.begin != NULL) {
1439                 for (size_t i = 0; i < 4; ++i) {
1440                         if (strcmp(visibilities[i], string.begin) == 0) {
1441                                 attribute->u.value = i;
1442                                 return;
1443                         }
1444                 }
1445                 errorf(HERE, "'%s' is an unrecognized visibility", string.begin);
1446         }
1447         attribute->invalid = true;
1448 }
1449
1450 /**
1451  * Parse one (code) model of the given attribute.
1452  */
1453 static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
1454 {
1455         static const char *const visibilities[] = {
1456                 "small",
1457                 "medium",
1458                 "large"
1459         };
1460         string_t string = { NULL, 0 };
1461         parse_gnu_attribute_string_arg(attribute, &string);
1462         if (string.begin != NULL) {
1463                 for (int i = 0; i < 3; ++i) {
1464                         if (strcmp(visibilities[i], string.begin) == 0) {
1465                                 attribute->u.value = i;
1466                                 return;
1467                         }
1468                 }
1469                 errorf(HERE, "'%s' is an unrecognized model", string.begin);
1470         }
1471         attribute->invalid = true;
1472 }
1473
1474 /**
1475  * Parse one mode of the given attribute.
1476  */
1477 static void parse_gnu_attribute_mode_arg(gnu_attribute_t *attribute)
1478 {
1479         /* TODO: find out what is allowed here... */
1480
1481         /* at least: byte, word, pointer, list of machine modes
1482          * __XXX___ is interpreted as XXX */
1483         add_anchor_token(')');
1484
1485         if (token.type != T_IDENTIFIER) {
1486                 expect(T_IDENTIFIER, end_error);
1487         }
1488
1489         /* This isn't really correct, the backend should provide a list of machine
1490          * specific modes (according to gcc philosophy that is...) */
1491         const char *symbol_str = token.v.symbol->string;
1492         if (strcmp_underscore("QI",   symbol_str) == 0 ||
1493             strcmp_underscore("byte", symbol_str) == 0) {
1494                 attribute->u.akind = ATOMIC_TYPE_CHAR;
1495         } else if (strcmp_underscore("HI", symbol_str) == 0) {
1496                 attribute->u.akind = ATOMIC_TYPE_SHORT;
1497         } else if (strcmp_underscore("SI",      symbol_str) == 0
1498                 || strcmp_underscore("word",    symbol_str) == 0
1499                 || strcmp_underscore("pointer", symbol_str) == 0) {
1500                 attribute->u.akind = ATOMIC_TYPE_INT;
1501         } else if (strcmp_underscore("DI", symbol_str) == 0) {
1502                 attribute->u.akind = ATOMIC_TYPE_LONGLONG;
1503         } else {
1504                 if (warning.other)
1505                         warningf(HERE, "ignoring unknown mode '%s'", symbol_str);
1506                 attribute->invalid = true;
1507         }
1508         next_token();
1509
1510         rem_anchor_token(')');
1511         expect(')', end_error);
1512         return;
1513 end_error:
1514         attribute->invalid = true;
1515 }
1516
1517 /**
1518  * Parse one interrupt argument of the given attribute.
1519  */
1520 static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
1521 {
1522         static const char *const interrupts[] = {
1523                 "IRQ",
1524                 "FIQ",
1525                 "SWI",
1526                 "ABORT",
1527                 "UNDEF"
1528         };
1529         string_t string = { NULL, 0 };
1530         parse_gnu_attribute_string_arg(attribute, &string);
1531         if (string.begin != NULL) {
1532                 for (size_t i = 0; i < 5; ++i) {
1533                         if (strcmp(interrupts[i], string.begin) == 0) {
1534                                 attribute->u.value = i;
1535                                 return;
1536                         }
1537                 }
1538                 errorf(HERE, "'%s' is not an interrupt", string.begin);
1539         }
1540         attribute->invalid = true;
1541 }
1542
1543 /**
1544  * Parse ( identifier, const expression, const expression )
1545  */
1546 static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
1547 {
1548         static const char *const format_names[] = {
1549                 "printf",
1550                 "scanf",
1551                 "strftime",
1552                 "strfmon"
1553         };
1554         int i;
1555
1556         if (token.type != T_IDENTIFIER) {
1557                 parse_error_expected("while parsing format attribute directive", T_IDENTIFIER, NULL);
1558                 goto end_error;
1559         }
1560         const char *name = token.v.symbol->string;
1561         for (i = 0; i < 4; ++i) {
1562                 if (strcmp_underscore(format_names[i], name) == 0)
1563                         break;
1564         }
1565         if (i >= 4) {
1566                 if (warning.attribute)
1567                         warningf(HERE, "'%s' is an unrecognized format function type", name);
1568         }
1569         next_token();
1570
1571         expect(',', end_error);
1572         add_anchor_token(')');
1573         add_anchor_token(',');
1574         parse_constant_expression();
1575         rem_anchor_token(',');
1576         rem_anchor_token(')');
1577
1578         expect(',', end_error);
1579         add_anchor_token(')');
1580         parse_constant_expression();
1581         rem_anchor_token(')');
1582         expect(')', end_error);
1583         return;
1584 end_error:
1585         attribute->u.value = true;
1586 }
1587
1588 /**
1589  * Check that a given GNU attribute has no arguments.
1590  */
1591 static void check_no_argument(gnu_attribute_t *attribute, const char *name)
1592 {
1593         if (!attribute->have_arguments)
1594                 return;
1595
1596         /* should have no arguments */
1597         errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1598         eat_until_matching_token('(');
1599         /* we have already consumed '(', so we stop before ')', eat it */
1600         eat(')');
1601         attribute->invalid = true;
1602 }
1603
1604 /**
1605  * Parse one GNU attribute.
1606  *
1607  * Note that attribute names can be specified WITH or WITHOUT
1608  * double underscores, ie const or __const__.
1609  *
1610  * The following attributes are parsed without arguments
1611  *  const
1612  *  volatile
1613  *  cdecl
1614  *  stdcall
1615  *  fastcall
1616  *  deprecated
1617  *  noinline
1618  *  noreturn
1619  *  naked
1620  *  pure
1621  *  always_inline
1622  *  malloc
1623  *  weak
1624  *  constructor
1625  *  destructor
1626  *  nothrow
1627  *  transparent_union
1628  *  common
1629  *  nocommon
1630  *  packed
1631  *  shared
1632  *  notshared
1633  *  used
1634  *  unused
1635  *  no_instrument_function
1636  *  warn_unused_result
1637  *  longcall
1638  *  shortcall
1639  *  long_call
1640  *  short_call
1641  *  function_vector
1642  *  interrupt_handler
1643  *  nmi_handler
1644  *  nesting
1645  *  near
1646  *  far
1647  *  signal
1648  *  eightbit_data
1649  *  tiny_data
1650  *  saveall
1651  *  flatten
1652  *  sseregparm
1653  *  externally_visible
1654  *  return_twice
1655  *  may_alias
1656  *  ms_struct
1657  *  gcc_struct
1658  *  dllimport
1659  *  dllexport
1660  *
1661  * The following attributes are parsed with arguments
1662  *  aligned( const expression )
1663  *  alias( string literal )
1664  *  section( string literal )
1665  *  format( identifier, const expression, const expression )
1666  *  format_arg( const expression )
1667  *  tls_model( string literal )
1668  *  visibility( string literal )
1669  *  regparm( const expression )
1670  *  model( string leteral )
1671  *  trap_exit( const expression )
1672  *  sp_switch( string literal )
1673  *
1674  * The following attributes might have arguments
1675  *  weak_ref( string literal )
1676  *  non_null( const expression // ',' )
1677  *  interrupt( string literal )
1678  *  sentinel( constant expression )
1679  */
1680 static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
1681 {
1682         gnu_attribute_t *head      = *attributes;
1683         gnu_attribute_t *last      = *attributes;
1684         decl_modifiers_t modifiers = 0;
1685         gnu_attribute_t *attribute;
1686
1687         eat(T___attribute__);
1688         expect('(', end_error);
1689         expect('(', end_error);
1690
1691         if (token.type != ')') {
1692                 /* find the end of the list */
1693                 if (last != NULL) {
1694                         while (last->next != NULL)
1695                                 last = last->next;
1696                 }
1697
1698                 /* non-empty attribute list */
1699                 while (true) {
1700                         const char *name;
1701                         if (token.type == T_const) {
1702                                 name = "const";
1703                         } else if (token.type == T_volatile) {
1704                                 name = "volatile";
1705                         } else if (token.type == T_cdecl) {
1706                                 /* __attribute__((cdecl)), WITH ms mode */
1707                                 name = "cdecl";
1708                         } else if (token.type == T_IDENTIFIER) {
1709                                 const symbol_t *sym = token.v.symbol;
1710                                 name = sym->string;
1711                         } else {
1712                                 parse_error_expected("while parsing GNU attribute", T_IDENTIFIER, NULL);
1713                                 break;
1714                         }
1715
1716                         next_token();
1717
1718                         int i;
1719                         for (i = 0; i < GNU_AK_LAST; ++i) {
1720                                 if (strcmp_underscore(gnu_attribute_names[i], name) == 0)
1721                                         break;
1722                         }
1723                         gnu_attribute_kind_t kind = (gnu_attribute_kind_t)i;
1724
1725                         attribute = NULL;
1726                         if (kind == GNU_AK_LAST) {
1727                                 if (warning.attribute)
1728                                         warningf(HERE, "'%s' attribute directive ignored", name);
1729
1730                                 /* skip possible arguments */
1731                                 if (token.type == '(') {
1732                                         eat_until_matching_token(')');
1733                                 }
1734                         } else {
1735                                 /* check for arguments */
1736                                 attribute = allocate_gnu_attribute(kind);
1737                                 if (token.type == '(') {
1738                                         next_token();
1739                                         if (token.type == ')') {
1740                                                 /* empty args are allowed */
1741                                                 next_token();
1742                                         } else
1743                                                 attribute->have_arguments = true;
1744                                 }
1745
1746                                 switch (kind) {
1747                                 case GNU_AK_VOLATILE:
1748                                 case GNU_AK_NAKED:
1749                                 case GNU_AK_MALLOC:
1750                                 case GNU_AK_WEAK:
1751                                 case GNU_AK_COMMON:
1752                                 case GNU_AK_NOCOMMON:
1753                                 case GNU_AK_SHARED:
1754                                 case GNU_AK_NOTSHARED:
1755                                 case GNU_AK_NO_INSTRUMENT_FUNCTION:
1756                                 case GNU_AK_WARN_UNUSED_RESULT:
1757                                 case GNU_AK_LONGCALL:
1758                                 case GNU_AK_SHORTCALL:
1759                                 case GNU_AK_LONG_CALL:
1760                                 case GNU_AK_SHORT_CALL:
1761                                 case GNU_AK_FUNCTION_VECTOR:
1762                                 case GNU_AK_INTERRUPT_HANDLER:
1763                                 case GNU_AK_NMI_HANDLER:
1764                                 case GNU_AK_NESTING:
1765                                 case GNU_AK_NEAR:
1766                                 case GNU_AK_FAR:
1767                                 case GNU_AK_SIGNAL:
1768                                 case GNU_AK_EIGTHBIT_DATA:
1769                                 case GNU_AK_TINY_DATA:
1770                                 case GNU_AK_SAVEALL:
1771                                 case GNU_AK_FLATTEN:
1772                                 case GNU_AK_SSEREGPARM:
1773                                 case GNU_AK_EXTERNALLY_VISIBLE:
1774                                 case GNU_AK_RETURN_TWICE:
1775                                 case GNU_AK_MAY_ALIAS:
1776                                 case GNU_AK_MS_STRUCT:
1777                                 case GNU_AK_GCC_STRUCT:
1778                                         goto no_arg;
1779
1780                                 case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
1781                                 case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
1782                                 case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
1783                                 case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
1784                                 case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
1785                                 case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
1786                                 case GNU_AK_CONST:             modifiers |= DM_CONST;             goto no_arg;
1787                                 case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
1788                                 case GNU_AK_DLLIMPORT:         modifiers |= DM_DLLIMPORT;         goto no_arg;
1789                                 case GNU_AK_DLLEXPORT:         modifiers |= DM_DLLEXPORT;         goto no_arg;
1790                                 case GNU_AK_PACKED:            modifiers |= DM_PACKED;            goto no_arg;
1791                                 case GNU_AK_NOINLINE:          modifiers |= DM_NOINLINE;          goto no_arg;
1792                                 case GNU_AK_RETURNS_TWICE:     modifiers |= DM_RETURNS_TWICE;     goto no_arg;
1793                                 case GNU_AK_NORETURN:          modifiers |= DM_NORETURN;          goto no_arg;
1794                                 case GNU_AK_NOTHROW:           modifiers |= DM_NOTHROW;           goto no_arg;
1795                                 case GNU_AK_TRANSPARENT_UNION: modifiers |= DM_TRANSPARENT_UNION; goto no_arg;
1796                                 case GNU_AK_CONSTRUCTOR:       modifiers |= DM_CONSTRUCTOR;       goto no_arg;
1797                                 case GNU_AK_DESTRUCTOR:        modifiers |= DM_DESTRUCTOR;        goto no_arg;
1798                                 case GNU_AK_DEPRECATED:        modifiers |= DM_DEPRECATED;        goto no_arg;
1799
1800                                 case GNU_AK_ALIGNED:
1801                                         /* __align__ may be used without an argument */
1802                                         if (attribute->have_arguments) {
1803                                                 parse_gnu_attribute_const_arg(attribute);
1804                                         }
1805                                         break;
1806
1807                                 case GNU_AK_FORMAT_ARG:
1808                                 case GNU_AK_REGPARM:
1809                                 case GNU_AK_TRAP_EXIT:
1810                                         if (!attribute->have_arguments) {
1811                                                 /* should have arguments */
1812                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1813                                                 attribute->invalid = true;
1814                                         } else
1815                                                 parse_gnu_attribute_const_arg(attribute);
1816                                         break;
1817                                 case GNU_AK_ALIAS:
1818                                 case GNU_AK_SECTION:
1819                                 case GNU_AK_SP_SWITCH:
1820                                         if (!attribute->have_arguments) {
1821                                                 /* should have arguments */
1822                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1823                                                 attribute->invalid = true;
1824                                         } else
1825                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1826                                         break;
1827                                 case GNU_AK_FORMAT:
1828                                         if (!attribute->have_arguments) {
1829                                                 /* should have arguments */
1830                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1831                                                 attribute->invalid = true;
1832                                         } else
1833                                                 parse_gnu_attribute_format_args(attribute);
1834                                         break;
1835                                 case GNU_AK_WEAKREF:
1836                                         /* may have one string argument */
1837                                         if (attribute->have_arguments)
1838                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1839                                         break;
1840                                 case GNU_AK_NONNULL:
1841                                         if (attribute->have_arguments)
1842                                                 parse_gnu_attribute_const_arg_list(attribute);
1843                                         break;
1844                                 case GNU_AK_TLS_MODEL:
1845                                         if (!attribute->have_arguments) {
1846                                                 /* should have arguments */
1847                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1848                                         } else
1849                                                 parse_gnu_attribute_tls_model_arg(attribute);
1850                                         break;
1851                                 case GNU_AK_VISIBILITY:
1852                                         if (!attribute->have_arguments) {
1853                                                 /* should have arguments */
1854                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1855                                         } else
1856                                                 parse_gnu_attribute_visibility_arg(attribute);
1857                                         break;
1858                                 case GNU_AK_MODEL:
1859                                         if (!attribute->have_arguments) {
1860                                                 /* should have arguments */
1861                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1862                                         } else {
1863                                                 parse_gnu_attribute_model_arg(attribute);
1864                                         }
1865                                         break;
1866                                 case GNU_AK_MODE:
1867                                         if (!attribute->have_arguments) {
1868                                                 /* should have arguments */
1869                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1870                                         } else {
1871                                                 parse_gnu_attribute_mode_arg(attribute);
1872                                         }
1873                                         break;
1874                                 case GNU_AK_INTERRUPT:
1875                                         /* may have one string argument */
1876                                         if (attribute->have_arguments)
1877                                                 parse_gnu_attribute_interrupt_arg(attribute);
1878                                         break;
1879                                 case GNU_AK_SENTINEL:
1880                                         /* may have one string argument */
1881                                         if (attribute->have_arguments)
1882                                                 parse_gnu_attribute_const_arg(attribute);
1883                                         break;
1884                                 case GNU_AK_LAST:
1885                                         /* already handled */
1886                                         break;
1887
1888 no_arg:
1889                                         check_no_argument(attribute, name);
1890                                 }
1891                         }
1892                         if (attribute != NULL) {
1893                                 if (last != NULL) {
1894                                         last->next = attribute;
1895                                         last       = attribute;
1896                                 } else {
1897                                         head = last = attribute;
1898                                 }
1899                         }
1900
1901                         if (token.type != ',')
1902                                 break;
1903                         next_token();
1904                 }
1905         }
1906         expect(')', end_error);
1907         expect(')', end_error);
1908 end_error:
1909         *attributes = head;
1910
1911         return modifiers;
1912 }
1913
1914 /**
1915  * Parse GNU attributes.
1916  */
1917 static decl_modifiers_t parse_attributes(gnu_attribute_t **attributes)
1918 {
1919         decl_modifiers_t modifiers = 0;
1920
1921         while (true) {
1922                 switch (token.type) {
1923                 case T___attribute__:
1924                         modifiers |= parse_gnu_attribute(attributes);
1925                         continue;
1926
1927                 case T_asm:
1928                         next_token();
1929                         expect('(', end_error);
1930                         if (token.type != T_STRING_LITERAL) {
1931                                 parse_error_expected("while parsing assembler attribute",
1932                                                      T_STRING_LITERAL, NULL);
1933                                 eat_until_matching_token('(');
1934                                 break;
1935                         } else {
1936                                 parse_string_literals();
1937                         }
1938                         expect(')', end_error);
1939                         continue;
1940
1941                 case T_cdecl:     modifiers |= DM_CDECL;    break;
1942                 case T__fastcall: modifiers |= DM_FASTCALL; break;
1943                 case T__stdcall:  modifiers |= DM_STDCALL;  break;
1944
1945                 case T___thiscall:
1946                         /* TODO record modifier */
1947                         if (warning.other)
1948                                 warningf(HERE, "Ignoring declaration modifier %K", &token);
1949                         break;
1950
1951 end_error:
1952                 default: return modifiers;
1953                 }
1954
1955                 next_token();
1956         }
1957 }
1958
1959 static void mark_vars_read(expression_t *expr, entity_t *lhs_ent);
1960
1961 static entity_t *determine_lhs_ent(expression_t *const expr,
1962                                    entity_t *lhs_ent)
1963 {
1964         switch (expr->kind) {
1965                 case EXPR_REFERENCE: {
1966                         entity_t *const entity = expr->reference.entity;
1967                         /* we should only find variables as lvalues... */
1968                         if (entity->base.kind != ENTITY_VARIABLE
1969                                         && entity->base.kind != ENTITY_PARAMETER)
1970                                 return NULL;
1971
1972                         return entity;
1973                 }
1974
1975                 case EXPR_ARRAY_ACCESS: {
1976                         expression_t *const ref = expr->array_access.array_ref;
1977                         entity_t     *      ent = NULL;
1978                         if (is_type_array(skip_typeref(revert_automatic_type_conversion(ref)))) {
1979                                 ent     = determine_lhs_ent(ref, lhs_ent);
1980                                 lhs_ent = ent;
1981                         } else {
1982                                 mark_vars_read(expr->select.compound, lhs_ent);
1983                         }
1984                         mark_vars_read(expr->array_access.index, lhs_ent);
1985                         return ent;
1986                 }
1987
1988                 case EXPR_SELECT: {
1989                         if (is_type_compound(skip_typeref(expr->base.type))) {
1990                                 return determine_lhs_ent(expr->select.compound, lhs_ent);
1991                         } else {
1992                                 mark_vars_read(expr->select.compound, lhs_ent);
1993                                 return NULL;
1994                         }
1995                 }
1996
1997                 case EXPR_UNARY_DEREFERENCE: {
1998                         expression_t *const val = expr->unary.value;
1999                         if (val->kind == EXPR_UNARY_TAKE_ADDRESS) {
2000                                 /* *&x is a NOP */
2001                                 return determine_lhs_ent(val->unary.value, lhs_ent);
2002                         } else {
2003                                 mark_vars_read(val, NULL);
2004                                 return NULL;
2005                         }
2006                 }
2007
2008                 default:
2009                         mark_vars_read(expr, NULL);
2010                         return NULL;
2011         }
2012 }
2013
2014 #define ENT_ANY ((entity_t*)-1)
2015
2016 /**
2017  * Mark declarations, which are read.  This is used to detect variables, which
2018  * are never read.
2019  * Example:
2020  * x = x + 1;
2021  *   x is not marked as "read", because it is only read to calculate its own new
2022  *   value.
2023  *
2024  * x += y; y += x;
2025  *   x and y are not detected as "not read", because multiple variables are
2026  *   involved.
2027  */
2028 static void mark_vars_read(expression_t *const expr, entity_t *lhs_ent)
2029 {
2030         switch (expr->kind) {
2031                 case EXPR_REFERENCE: {
2032                         entity_t *const entity = expr->reference.entity;
2033                         if (entity->kind != ENTITY_VARIABLE
2034                                         && entity->kind != ENTITY_PARAMETER)
2035                                 return;
2036
2037                         if (lhs_ent != entity && lhs_ent != ENT_ANY) {
2038                                 if (entity->kind == ENTITY_VARIABLE) {
2039                                         entity->variable.read = true;
2040                                 } else {
2041                                         entity->parameter.read = true;
2042                                 }
2043                         }
2044                         return;
2045                 }
2046
2047                 case EXPR_CALL:
2048                         // TODO respect pure/const
2049                         mark_vars_read(expr->call.function, NULL);
2050                         for (call_argument_t *arg = expr->call.arguments; arg != NULL; arg = arg->next) {
2051                                 mark_vars_read(arg->expression, NULL);
2052                         }
2053                         return;
2054
2055                 case EXPR_CONDITIONAL:
2056                         // TODO lhs_decl should depend on whether true/false have an effect
2057                         mark_vars_read(expr->conditional.condition, NULL);
2058                         if (expr->conditional.true_expression != NULL)
2059                                 mark_vars_read(expr->conditional.true_expression, lhs_ent);
2060                         mark_vars_read(expr->conditional.false_expression, lhs_ent);
2061                         return;
2062
2063                 case EXPR_SELECT:
2064                         if (lhs_ent == ENT_ANY
2065                                         && !is_type_compound(skip_typeref(expr->base.type)))
2066                                 lhs_ent = NULL;
2067                         mark_vars_read(expr->select.compound, lhs_ent);
2068                         return;
2069
2070                 case EXPR_ARRAY_ACCESS: {
2071                         expression_t *const ref = expr->array_access.array_ref;
2072                         mark_vars_read(ref, lhs_ent);
2073                         lhs_ent = determine_lhs_ent(ref, lhs_ent);
2074                         mark_vars_read(expr->array_access.index, lhs_ent);
2075                         return;
2076                 }
2077
2078                 case EXPR_VA_ARG:
2079                         mark_vars_read(expr->va_arge.ap, lhs_ent);
2080                         return;
2081
2082                 case EXPR_UNARY_CAST:
2083                         /* Special case: Use void cast to mark a variable as "read" */
2084                         if (is_type_atomic(skip_typeref(expr->base.type), ATOMIC_TYPE_VOID))
2085                                 lhs_ent = NULL;
2086                         goto unary;
2087
2088
2089                 case EXPR_UNARY_THROW:
2090                         if (expr->unary.value == NULL)
2091                                 return;
2092                         /* FALLTHROUGH */
2093                 case EXPR_UNARY_DEREFERENCE:
2094                 case EXPR_UNARY_DELETE:
2095                 case EXPR_UNARY_DELETE_ARRAY:
2096                         if (lhs_ent == ENT_ANY)
2097                                 lhs_ent = NULL;
2098                         goto unary;
2099
2100                 case EXPR_UNARY_NEGATE:
2101                 case EXPR_UNARY_PLUS:
2102                 case EXPR_UNARY_BITWISE_NEGATE:
2103                 case EXPR_UNARY_NOT:
2104                 case EXPR_UNARY_TAKE_ADDRESS:
2105                 case EXPR_UNARY_POSTFIX_INCREMENT:
2106                 case EXPR_UNARY_POSTFIX_DECREMENT:
2107                 case EXPR_UNARY_PREFIX_INCREMENT:
2108                 case EXPR_UNARY_PREFIX_DECREMENT:
2109                 case EXPR_UNARY_CAST_IMPLICIT:
2110                 case EXPR_UNARY_ASSUME:
2111 unary:
2112                         mark_vars_read(expr->unary.value, lhs_ent);
2113                         return;
2114
2115                 case EXPR_BINARY_ADD:
2116                 case EXPR_BINARY_SUB:
2117                 case EXPR_BINARY_MUL:
2118                 case EXPR_BINARY_DIV:
2119                 case EXPR_BINARY_MOD:
2120                 case EXPR_BINARY_EQUAL:
2121                 case EXPR_BINARY_NOTEQUAL:
2122                 case EXPR_BINARY_LESS:
2123                 case EXPR_BINARY_LESSEQUAL:
2124                 case EXPR_BINARY_GREATER:
2125                 case EXPR_BINARY_GREATEREQUAL:
2126                 case EXPR_BINARY_BITWISE_AND:
2127                 case EXPR_BINARY_BITWISE_OR:
2128                 case EXPR_BINARY_BITWISE_XOR:
2129                 case EXPR_BINARY_LOGICAL_AND:
2130                 case EXPR_BINARY_LOGICAL_OR:
2131                 case EXPR_BINARY_SHIFTLEFT:
2132                 case EXPR_BINARY_SHIFTRIGHT:
2133                 case EXPR_BINARY_COMMA:
2134                 case EXPR_BINARY_ISGREATER:
2135                 case EXPR_BINARY_ISGREATEREQUAL:
2136                 case EXPR_BINARY_ISLESS:
2137                 case EXPR_BINARY_ISLESSEQUAL:
2138                 case EXPR_BINARY_ISLESSGREATER:
2139                 case EXPR_BINARY_ISUNORDERED:
2140                         mark_vars_read(expr->binary.left,  lhs_ent);
2141                         mark_vars_read(expr->binary.right, lhs_ent);
2142                         return;
2143
2144                 case EXPR_BINARY_ASSIGN:
2145                 case EXPR_BINARY_MUL_ASSIGN:
2146                 case EXPR_BINARY_DIV_ASSIGN:
2147                 case EXPR_BINARY_MOD_ASSIGN:
2148                 case EXPR_BINARY_ADD_ASSIGN:
2149                 case EXPR_BINARY_SUB_ASSIGN:
2150                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:
2151                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:
2152                 case EXPR_BINARY_BITWISE_AND_ASSIGN:
2153                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:
2154                 case EXPR_BINARY_BITWISE_OR_ASSIGN: {
2155                         if (lhs_ent == ENT_ANY)
2156                                 lhs_ent = NULL;
2157                         lhs_ent = determine_lhs_ent(expr->binary.left, lhs_ent);
2158                         mark_vars_read(expr->binary.right, lhs_ent);
2159                         return;
2160                 }
2161
2162                 case EXPR_VA_START:
2163                         determine_lhs_ent(expr->va_starte.ap, lhs_ent);
2164                         return;
2165
2166                 case EXPR_UNKNOWN:
2167                 case EXPR_INVALID:
2168                 case EXPR_CONST:
2169                 case EXPR_CHARACTER_CONSTANT:
2170                 case EXPR_WIDE_CHARACTER_CONSTANT:
2171                 case EXPR_STRING_LITERAL:
2172                 case EXPR_WIDE_STRING_LITERAL:
2173                 case EXPR_COMPOUND_LITERAL: // TODO init?
2174                 case EXPR_SIZEOF:
2175                 case EXPR_CLASSIFY_TYPE:
2176                 case EXPR_ALIGNOF:
2177                 case EXPR_FUNCNAME:
2178                 case EXPR_BUILTIN_SYMBOL:
2179                 case EXPR_BUILTIN_CONSTANT_P:
2180                 case EXPR_BUILTIN_PREFETCH:
2181                 case EXPR_OFFSETOF:
2182                 case EXPR_STATEMENT: // TODO
2183                 case EXPR_LABEL_ADDRESS:
2184                 case EXPR_REFERENCE_ENUM_VALUE:
2185                         return;
2186         }
2187
2188         panic("unhandled expression");
2189 }
2190
2191 static designator_t *parse_designation(void)
2192 {
2193         designator_t *result = NULL;
2194         designator_t *last   = NULL;
2195
2196         while (true) {
2197                 designator_t *designator;
2198                 switch (token.type) {
2199                 case '[':
2200                         designator = allocate_ast_zero(sizeof(designator[0]));
2201                         designator->source_position = token.source_position;
2202                         next_token();
2203                         add_anchor_token(']');
2204                         designator->array_index = parse_constant_expression();
2205                         rem_anchor_token(']');
2206                         expect(']', end_error);
2207                         break;
2208                 case '.':
2209                         designator = allocate_ast_zero(sizeof(designator[0]));
2210                         designator->source_position = token.source_position;
2211                         next_token();
2212                         if (token.type != T_IDENTIFIER) {
2213                                 parse_error_expected("while parsing designator",
2214                                                      T_IDENTIFIER, NULL);
2215                                 return NULL;
2216                         }
2217                         designator->symbol = token.v.symbol;
2218                         next_token();
2219                         break;
2220                 default:
2221                         expect('=', end_error);
2222                         return result;
2223                 }
2224
2225                 assert(designator != NULL);
2226                 if (last != NULL) {
2227                         last->next = designator;
2228                 } else {
2229                         result = designator;
2230                 }
2231                 last = designator;
2232         }
2233 end_error:
2234         return NULL;
2235 }
2236
2237 static initializer_t *initializer_from_string(array_type_t *type,
2238                                               const string_t *const string)
2239 {
2240         /* TODO: check len vs. size of array type */
2241         (void) type;
2242
2243         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
2244         initializer->string.string = *string;
2245
2246         return initializer;
2247 }
2248
2249 static initializer_t *initializer_from_wide_string(array_type_t *const type,
2250                                                    wide_string_t *const string)
2251 {
2252         /* TODO: check len vs. size of array type */
2253         (void) type;
2254
2255         initializer_t *const initializer =
2256                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
2257         initializer->wide_string.string = *string;
2258
2259         return initializer;
2260 }
2261
2262 /**
2263  * Build an initializer from a given expression.
2264  */
2265 static initializer_t *initializer_from_expression(type_t *orig_type,
2266                                                   expression_t *expression)
2267 {
2268         /* TODO check that expression is a constant expression */
2269
2270         /* § 6.7.8.14/15 char array may be initialized by string literals */
2271         type_t *type           = skip_typeref(orig_type);
2272         type_t *expr_type_orig = expression->base.type;
2273         type_t *expr_type      = skip_typeref(expr_type_orig);
2274         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
2275                 array_type_t *const array_type   = &type->array;
2276                 type_t       *const element_type = skip_typeref(array_type->element_type);
2277
2278                 if (element_type->kind == TYPE_ATOMIC) {
2279                         atomic_type_kind_t akind = element_type->atomic.akind;
2280                         switch (expression->kind) {
2281                                 case EXPR_STRING_LITERAL:
2282                                         if (akind == ATOMIC_TYPE_CHAR
2283                                                         || akind == ATOMIC_TYPE_SCHAR
2284                                                         || akind == ATOMIC_TYPE_UCHAR) {
2285                                                 return initializer_from_string(array_type,
2286                                                         &expression->string.value);
2287                                         }
2288
2289                                 case EXPR_WIDE_STRING_LITERAL: {
2290                                         type_t *bare_wchar_type = skip_typeref(type_wchar_t);
2291                                         if (get_unqualified_type(element_type) == bare_wchar_type) {
2292                                                 return initializer_from_wide_string(array_type,
2293                                                         &expression->wide_string.value);
2294                                         }
2295                                 }
2296
2297                                 default:
2298                                         break;
2299                         }
2300                 }
2301         }
2302
2303         assign_error_t error = semantic_assign(type, expression);
2304         if (error == ASSIGN_ERROR_INCOMPATIBLE)
2305                 return NULL;
2306         report_assign_error(error, type, expression, "initializer",
2307                             &expression->base.source_position);
2308
2309         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
2310 #if 0
2311         if (type->kind == TYPE_BITFIELD) {
2312                 type = type->bitfield.base_type;
2313         }
2314 #endif
2315         result->value.value = create_implicit_cast(expression, type);
2316
2317         return result;
2318 }
2319
2320 /**
2321  * Checks if a given expression can be used as an constant initializer.
2322  */
2323 static bool is_initializer_constant(const expression_t *expression)
2324 {
2325         return is_constant_expression(expression)
2326                 || is_address_constant(expression);
2327 }
2328
2329 /**
2330  * Parses an scalar initializer.
2331  *
2332  * § 6.7.8.11; eat {} without warning
2333  */
2334 static initializer_t *parse_scalar_initializer(type_t *type,
2335                                                bool must_be_constant)
2336 {
2337         /* there might be extra {} hierarchies */
2338         int braces = 0;
2339         if (token.type == '{') {
2340                 if (warning.other)
2341                         warningf(HERE, "extra curly braces around scalar initializer");
2342                 do {
2343                         ++braces;
2344                         next_token();
2345                 } while (token.type == '{');
2346         }
2347
2348         expression_t *expression = parse_assignment_expression();
2349         mark_vars_read(expression, NULL);
2350         if (must_be_constant && !is_initializer_constant(expression)) {
2351                 errorf(&expression->base.source_position,
2352                        "Initialisation expression '%E' is not constant",
2353                        expression);
2354         }
2355
2356         initializer_t *initializer = initializer_from_expression(type, expression);
2357
2358         if (initializer == NULL) {
2359                 errorf(&expression->base.source_position,
2360                        "expression '%E' (type '%T') doesn't match expected type '%T'",
2361                        expression, expression->base.type, type);
2362                 /* TODO */
2363                 return NULL;
2364         }
2365
2366         bool additional_warning_displayed = false;
2367         while (braces > 0) {
2368                 if (token.type == ',') {
2369                         next_token();
2370                 }
2371                 if (token.type != '}') {
2372                         if (!additional_warning_displayed && warning.other) {
2373                                 warningf(HERE, "additional elements in scalar initializer");
2374                                 additional_warning_displayed = true;
2375                         }
2376                 }
2377                 eat_block();
2378                 braces--;
2379         }
2380
2381         return initializer;
2382 }
2383
2384 /**
2385  * An entry in the type path.
2386  */
2387 typedef struct type_path_entry_t type_path_entry_t;
2388 struct type_path_entry_t {
2389         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
2390         union {
2391                 size_t         index;          /**< For array types: the current index. */
2392                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
2393         } v;
2394 };
2395
2396 /**
2397  * A type path expression a position inside compound or array types.
2398  */
2399 typedef struct type_path_t type_path_t;
2400 struct type_path_t {
2401         type_path_entry_t *path;         /**< An flexible array containing the current path. */
2402         type_t            *top_type;     /**< type of the element the path points */
2403         size_t             max_index;    /**< largest index in outermost array */
2404 };
2405
2406 /**
2407  * Prints a type path for debugging.
2408  */
2409 static __attribute__((unused)) void debug_print_type_path(
2410                 const type_path_t *path)
2411 {
2412         size_t len = ARR_LEN(path->path);
2413
2414         for (size_t i = 0; i < len; ++i) {
2415                 const type_path_entry_t *entry = & path->path[i];
2416
2417                 type_t *type = skip_typeref(entry->type);
2418                 if (is_type_compound(type)) {
2419                         /* in gcc mode structs can have no members */
2420                         if (entry->v.compound_entry == NULL) {
2421                                 assert(i == len-1);
2422                                 continue;
2423                         }
2424                         fprintf(stderr, ".%s",
2425                                 entry->v.compound_entry->base.symbol->string);
2426                 } else if (is_type_array(type)) {
2427                         fprintf(stderr, "[%u]", (unsigned) entry->v.index);
2428                 } else {
2429                         fprintf(stderr, "-INVALID-");
2430                 }
2431         }
2432         if (path->top_type != NULL) {
2433                 fprintf(stderr, "  (");
2434                 print_type(path->top_type);
2435                 fprintf(stderr, ")");
2436         }
2437 }
2438
2439 /**
2440  * Return the top type path entry, ie. in a path
2441  * (type).a.b returns the b.
2442  */
2443 static type_path_entry_t *get_type_path_top(const type_path_t *path)
2444 {
2445         size_t len = ARR_LEN(path->path);
2446         assert(len > 0);
2447         return &path->path[len-1];
2448 }
2449
2450 /**
2451  * Enlarge the type path by an (empty) element.
2452  */
2453 static type_path_entry_t *append_to_type_path(type_path_t *path)
2454 {
2455         size_t len = ARR_LEN(path->path);
2456         ARR_RESIZE(type_path_entry_t, path->path, len+1);
2457
2458         type_path_entry_t *result = & path->path[len];
2459         memset(result, 0, sizeof(result[0]));
2460         return result;
2461 }
2462
2463 /**
2464  * Descending into a sub-type. Enter the scope of the current top_type.
2465  */
2466 static void descend_into_subtype(type_path_t *path)
2467 {
2468         type_t *orig_top_type = path->top_type;
2469         type_t *top_type      = skip_typeref(orig_top_type);
2470
2471         type_path_entry_t *top = append_to_type_path(path);
2472         top->type              = top_type;
2473
2474         if (is_type_compound(top_type)) {
2475                 compound_t *compound  = top_type->compound.compound;
2476                 entity_t   *entry     = compound->members.entities;
2477
2478                 if (entry != NULL) {
2479                         assert(entry->kind == ENTITY_COMPOUND_MEMBER);
2480                         top->v.compound_entry = &entry->declaration;
2481                         path->top_type = entry->declaration.type;
2482                 } else {
2483                         path->top_type = NULL;
2484                 }
2485         } else if (is_type_array(top_type)) {
2486                 top->v.index   = 0;
2487                 path->top_type = top_type->array.element_type;
2488         } else {
2489                 assert(!is_type_valid(top_type));
2490         }
2491 }
2492
2493 /**
2494  * Pop an entry from the given type path, ie. returning from
2495  * (type).a.b to (type).a
2496  */
2497 static void ascend_from_subtype(type_path_t *path)
2498 {
2499         type_path_entry_t *top = get_type_path_top(path);
2500
2501         path->top_type = top->type;
2502
2503         size_t len = ARR_LEN(path->path);
2504         ARR_RESIZE(type_path_entry_t, path->path, len-1);
2505 }
2506
2507 /**
2508  * Pop entries from the given type path until the given
2509  * path level is reached.
2510  */
2511 static void ascend_to(type_path_t *path, size_t top_path_level)
2512 {
2513         size_t len = ARR_LEN(path->path);
2514
2515         while (len > top_path_level) {
2516                 ascend_from_subtype(path);
2517                 len = ARR_LEN(path->path);
2518         }
2519 }
2520
2521 static bool walk_designator(type_path_t *path, const designator_t *designator,
2522                             bool used_in_offsetof)
2523 {
2524         for (; designator != NULL; designator = designator->next) {
2525                 type_path_entry_t *top       = get_type_path_top(path);
2526                 type_t            *orig_type = top->type;
2527
2528                 type_t *type = skip_typeref(orig_type);
2529
2530                 if (designator->symbol != NULL) {
2531                         symbol_t *symbol = designator->symbol;
2532                         if (!is_type_compound(type)) {
2533                                 if (is_type_valid(type)) {
2534                                         errorf(&designator->source_position,
2535                                                "'.%Y' designator used for non-compound type '%T'",
2536                                                symbol, orig_type);
2537                                 }
2538
2539                                 top->type             = type_error_type;
2540                                 top->v.compound_entry = NULL;
2541                                 orig_type             = type_error_type;
2542                         } else {
2543                                 compound_t *compound = type->compound.compound;
2544                                 entity_t   *iter     = compound->members.entities;
2545                                 for (; iter != NULL; iter = iter->base.next) {
2546                                         if (iter->base.symbol == symbol) {
2547                                                 break;
2548                                         }
2549                                 }
2550                                 if (iter == NULL) {
2551                                         errorf(&designator->source_position,
2552                                                "'%T' has no member named '%Y'", orig_type, symbol);
2553                                         goto failed;
2554                                 }
2555                                 assert(iter->kind == ENTITY_COMPOUND_MEMBER);
2556                                 if (used_in_offsetof) {
2557                                         type_t *real_type = skip_typeref(iter->declaration.type);
2558                                         if (real_type->kind == TYPE_BITFIELD) {
2559                                                 errorf(&designator->source_position,
2560                                                        "offsetof designator '%Y' may not specify bitfield",
2561                                                        symbol);
2562                                                 goto failed;
2563                                         }
2564                                 }
2565
2566                                 top->type             = orig_type;
2567                                 top->v.compound_entry = &iter->declaration;
2568                                 orig_type             = iter->declaration.type;
2569                         }
2570                 } else {
2571                         expression_t *array_index = designator->array_index;
2572                         assert(designator->array_index != NULL);
2573
2574                         if (!is_type_array(type)) {
2575                                 if (is_type_valid(type)) {
2576                                         errorf(&designator->source_position,
2577                                                "[%E] designator used for non-array type '%T'",
2578                                                array_index, orig_type);
2579                                 }
2580                                 goto failed;
2581                         }
2582
2583                         long index = fold_constant(array_index);
2584                         if (!used_in_offsetof) {
2585                                 if (index < 0) {
2586                                         errorf(&designator->source_position,
2587                                                "array index [%E] must be positive", array_index);
2588                                 } else if (type->array.size_constant) {
2589                                         long array_size = type->array.size;
2590                                         if (index >= array_size) {
2591                                                 errorf(&designator->source_position,
2592                                                        "designator [%E] (%d) exceeds array size %d",
2593                                                        array_index, index, array_size);
2594                                         }
2595                                 }
2596                         }
2597
2598                         top->type    = orig_type;
2599                         top->v.index = (size_t) index;
2600                         orig_type    = type->array.element_type;
2601                 }
2602                 path->top_type = orig_type;
2603
2604                 if (designator->next != NULL) {
2605                         descend_into_subtype(path);
2606                 }
2607         }
2608         return true;
2609
2610 failed:
2611         return false;
2612 }
2613
2614 static void advance_current_object(type_path_t *path, size_t top_path_level)
2615 {
2616         type_path_entry_t *top = get_type_path_top(path);
2617
2618         type_t *type = skip_typeref(top->type);
2619         if (is_type_union(type)) {
2620                 /* in unions only the first element is initialized */
2621                 top->v.compound_entry = NULL;
2622         } else if (is_type_struct(type)) {
2623                 declaration_t *entry = top->v.compound_entry;
2624
2625                 entity_t *next_entity = entry->base.next;
2626                 if (next_entity != NULL) {
2627                         assert(is_declaration(next_entity));
2628                         entry = &next_entity->declaration;
2629                 } else {
2630                         entry = NULL;
2631                 }
2632
2633                 top->v.compound_entry = entry;
2634                 if (entry != NULL) {
2635                         path->top_type = entry->type;
2636                         return;
2637                 }
2638         } else if (is_type_array(type)) {
2639                 assert(is_type_array(type));
2640
2641                 top->v.index++;
2642
2643                 if (!type->array.size_constant || top->v.index < type->array.size) {
2644                         return;
2645                 }
2646         } else {
2647                 assert(!is_type_valid(type));
2648                 return;
2649         }
2650
2651         /* we're past the last member of the current sub-aggregate, try if we
2652          * can ascend in the type hierarchy and continue with another subobject */
2653         size_t len = ARR_LEN(path->path);
2654
2655         if (len > top_path_level) {
2656                 ascend_from_subtype(path);
2657                 advance_current_object(path, top_path_level);
2658         } else {
2659                 path->top_type = NULL;
2660         }
2661 }
2662
2663 /**
2664  * skip until token is found.
2665  */
2666 static void skip_until(int type)
2667 {
2668         while (token.type != type) {
2669                 if (token.type == T_EOF)
2670                         return;
2671                 next_token();
2672         }
2673 }
2674
2675 /**
2676  * skip any {...} blocks until a closing bracket is reached.
2677  */
2678 static void skip_initializers(void)
2679 {
2680         if (token.type == '{')
2681                 next_token();
2682
2683         while (token.type != '}') {
2684                 if (token.type == T_EOF)
2685                         return;
2686                 if (token.type == '{') {
2687                         eat_block();
2688                         continue;
2689                 }
2690                 next_token();
2691         }
2692 }
2693
2694 static initializer_t *create_empty_initializer(void)
2695 {
2696         static initializer_t empty_initializer
2697                 = { .list = { { INITIALIZER_LIST }, 0 } };
2698         return &empty_initializer;
2699 }
2700
2701 /**
2702  * Parse a part of an initialiser for a struct or union,
2703  */
2704 static initializer_t *parse_sub_initializer(type_path_t *path,
2705                 type_t *outer_type, size_t top_path_level,
2706                 parse_initializer_env_t *env)
2707 {
2708         if (token.type == '}') {
2709                 /* empty initializer */
2710                 return create_empty_initializer();
2711         }
2712
2713         type_t *orig_type = path->top_type;
2714         type_t *type      = NULL;
2715
2716         if (orig_type == NULL) {
2717                 /* We are initializing an empty compound. */
2718         } else {
2719                 type = skip_typeref(orig_type);
2720         }
2721
2722         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2723
2724         while (true) {
2725                 designator_t *designator = NULL;
2726                 if (token.type == '.' || token.type == '[') {
2727                         designator = parse_designation();
2728                         goto finish_designator;
2729                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2730                         /* GNU-style designator ("identifier: value") */
2731                         designator = allocate_ast_zero(sizeof(designator[0]));
2732                         designator->source_position = token.source_position;
2733                         designator->symbol          = token.v.symbol;
2734                         eat(T_IDENTIFIER);
2735                         eat(':');
2736
2737 finish_designator:
2738                         /* reset path to toplevel, evaluate designator from there */
2739                         ascend_to(path, top_path_level);
2740                         if (!walk_designator(path, designator, false)) {
2741                                 /* can't continue after designation error */
2742                                 goto end_error;
2743                         }
2744
2745                         initializer_t *designator_initializer
2746                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2747                         designator_initializer->designator.designator = designator;
2748                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2749
2750                         orig_type = path->top_type;
2751                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2752                 }
2753
2754                 initializer_t *sub;
2755
2756                 if (token.type == '{') {
2757                         if (type != NULL && is_type_scalar(type)) {
2758                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2759                         } else {
2760                                 eat('{');
2761                                 if (type == NULL) {
2762                                         if (env->entity != NULL) {
2763                                                 errorf(HERE,
2764                                                      "extra brace group at end of initializer for '%Y'",
2765                                                      env->entity->base.symbol);
2766                                         } else {
2767                                                 errorf(HERE, "extra brace group at end of initializer");
2768                                         }
2769                                 } else
2770                                         descend_into_subtype(path);
2771
2772                                 add_anchor_token('}');
2773                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2774                                                             env);
2775                                 rem_anchor_token('}');
2776
2777                                 if (type != NULL) {
2778                                         ascend_from_subtype(path);
2779                                         expect('}', end_error);
2780                                 } else {
2781                                         expect('}', end_error);
2782                                         goto error_parse_next;
2783                                 }
2784                         }
2785                 } else {
2786                         /* must be an expression */
2787                         expression_t *expression = parse_assignment_expression();
2788                         mark_vars_read(expression, NULL);
2789
2790                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2791                                 errorf(&expression->base.source_position,
2792                                        "Initialisation expression '%E' is not constant",
2793                                        expression);
2794                         }
2795
2796                         if (type == NULL) {
2797                                 /* we are already outside, ... */
2798                                 type_t *const outer_type_skip = skip_typeref(outer_type);
2799                                 if (is_type_compound(outer_type_skip) &&
2800                                     !outer_type_skip->compound.compound->complete) {
2801                                         goto error_parse_next;
2802                                 }
2803                                 goto error_excess;
2804                         }
2805
2806                         /* handle { "string" } special case */
2807                         if ((expression->kind == EXPR_STRING_LITERAL
2808                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2809                                         && outer_type != NULL) {
2810                                 sub = initializer_from_expression(outer_type, expression);
2811                                 if (sub != NULL) {
2812                                         if (token.type == ',') {
2813                                                 next_token();
2814                                         }
2815                                         if (token.type != '}' && warning.other) {
2816                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2817                                                                  orig_type);
2818                                         }
2819                                         /* TODO: eat , ... */
2820                                         return sub;
2821                                 }
2822                         }
2823
2824                         /* descend into subtypes until expression matches type */
2825                         while (true) {
2826                                 orig_type = path->top_type;
2827                                 type      = skip_typeref(orig_type);
2828
2829                                 sub = initializer_from_expression(orig_type, expression);
2830                                 if (sub != NULL) {
2831                                         break;
2832                                 }
2833                                 if (!is_type_valid(type)) {
2834                                         goto end_error;
2835                                 }
2836                                 if (is_type_scalar(type)) {
2837                                         errorf(&expression->base.source_position,
2838                                                         "expression '%E' doesn't match expected type '%T'",
2839                                                         expression, orig_type);
2840                                         goto end_error;
2841                                 }
2842
2843                                 descend_into_subtype(path);
2844                         }
2845                 }
2846
2847                 /* update largest index of top array */
2848                 const type_path_entry_t *first      = &path->path[0];
2849                 type_t                  *first_type = first->type;
2850                 first_type                          = skip_typeref(first_type);
2851                 if (is_type_array(first_type)) {
2852                         size_t index = first->v.index;
2853                         if (index > path->max_index)
2854                                 path->max_index = index;
2855                 }
2856
2857                 if (type != NULL) {
2858                         /* append to initializers list */
2859                         ARR_APP1(initializer_t*, initializers, sub);
2860                 } else {
2861 error_excess:
2862                         if (warning.other) {
2863                                 if (env->entity != NULL) {
2864                                         warningf(HERE, "excess elements in struct initializer for '%Y'",
2865                                            env->entity->base.symbol);
2866                                 } else {
2867                                         warningf(HERE, "excess elements in struct initializer");
2868                                 }
2869                         }
2870                 }
2871
2872 error_parse_next:
2873                 if (token.type == '}') {
2874                         break;
2875                 }
2876                 expect(',', end_error);
2877                 if (token.type == '}') {
2878                         break;
2879                 }
2880
2881                 if (type != NULL) {
2882                         /* advance to the next declaration if we are not at the end */
2883                         advance_current_object(path, top_path_level);
2884                         orig_type = path->top_type;
2885                         if (orig_type != NULL)
2886                                 type = skip_typeref(orig_type);
2887                         else
2888                                 type = NULL;
2889                 }
2890         }
2891
2892         size_t len  = ARR_LEN(initializers);
2893         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2894         initializer_t *result = allocate_ast_zero(size);
2895         result->kind          = INITIALIZER_LIST;
2896         result->list.len      = len;
2897         memcpy(&result->list.initializers, initializers,
2898                len * sizeof(initializers[0]));
2899
2900         DEL_ARR_F(initializers);
2901         ascend_to(path, top_path_level+1);
2902
2903         return result;
2904
2905 end_error:
2906         skip_initializers();
2907         DEL_ARR_F(initializers);
2908         ascend_to(path, top_path_level+1);
2909         return NULL;
2910 }
2911
2912 /**
2913  * Parses an initializer. Parsers either a compound literal
2914  * (env->declaration == NULL) or an initializer of a declaration.
2915  */
2916 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2917 {
2918         type_t        *type      = skip_typeref(env->type);
2919         size_t         max_index = 0xdeadbeaf;   // TODO: Resolve this uninitialized variable problem
2920         initializer_t *result;
2921
2922         if (is_type_scalar(type)) {
2923                 result = parse_scalar_initializer(type, env->must_be_constant);
2924         } else if (token.type == '{') {
2925                 eat('{');
2926
2927                 type_path_t path;
2928                 memset(&path, 0, sizeof(path));
2929                 path.top_type = env->type;
2930                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2931
2932                 descend_into_subtype(&path);
2933
2934                 add_anchor_token('}');
2935                 result = parse_sub_initializer(&path, env->type, 1, env);
2936                 rem_anchor_token('}');
2937
2938                 max_index = path.max_index;
2939                 DEL_ARR_F(path.path);
2940
2941                 expect('}', end_error);
2942         } else {
2943                 /* parse_scalar_initializer() also works in this case: we simply
2944                  * have an expression without {} around it */
2945                 result = parse_scalar_initializer(type, env->must_be_constant);
2946         }
2947
2948         /* § 6.7.8 (22) array initializers for arrays with unknown size determine
2949          * the array type size */
2950         if (is_type_array(type) && type->array.size_expression == NULL
2951                         && result != NULL) {
2952                 size_t size;
2953                 switch (result->kind) {
2954                 case INITIALIZER_LIST:
2955                         assert(max_index != 0xdeadbeaf);
2956                         size = max_index + 1;
2957                         break;
2958
2959                 case INITIALIZER_STRING:
2960                         size = result->string.string.size;
2961                         break;
2962
2963                 case INITIALIZER_WIDE_STRING:
2964                         size = result->wide_string.string.size;
2965                         break;
2966
2967                 case INITIALIZER_DESIGNATOR:
2968                 case INITIALIZER_VALUE:
2969                         /* can happen for parse errors */
2970                         size = 0;
2971                         break;
2972
2973                 default:
2974                         internal_errorf(HERE, "invalid initializer type");
2975                 }
2976
2977                 expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2978                 cnst->base.type          = type_size_t;
2979                 cnst->conste.v.int_value = size;
2980
2981                 type_t *new_type = duplicate_type(type);
2982
2983                 new_type->array.size_expression   = cnst;
2984                 new_type->array.size_constant     = true;
2985                 new_type->array.has_implicit_size = true;
2986                 new_type->array.size              = size;
2987                 env->type = new_type;
2988         }
2989
2990         return result;
2991 end_error:
2992         return NULL;
2993 }
2994
2995 static void append_entity(scope_t *scope, entity_t *entity)
2996 {
2997         if (scope->last_entity != NULL) {
2998                 scope->last_entity->base.next = entity;
2999         } else {
3000                 scope->entities = entity;
3001         }
3002         scope->last_entity = entity;
3003 }
3004
3005
3006 static compound_t *parse_compound_type_specifier(bool is_struct)
3007 {
3008         gnu_attribute_t  *attributes = NULL;
3009         decl_modifiers_t  modifiers  = 0;
3010         if (is_struct) {
3011                 eat(T_struct);
3012         } else {
3013                 eat(T_union);
3014         }
3015
3016         symbol_t   *symbol   = NULL;
3017         compound_t *compound = NULL;
3018
3019         if (token.type == T___attribute__) {
3020                 modifiers |= parse_attributes(&attributes);
3021         }
3022
3023         if (token.type == T_IDENTIFIER) {
3024                 symbol = token.v.symbol;
3025                 next_token();
3026
3027                 namespace_tag_t const namespc =
3028                         is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION;
3029                 entity_t *entity = get_entity(symbol, namespc);
3030                 if (entity != NULL) {
3031                         assert(entity->kind == (is_struct ? ENTITY_STRUCT : ENTITY_UNION));
3032                         compound = &entity->compound;
3033                         if (compound->base.parent_scope != current_scope &&
3034                             (token.type == '{' || token.type == ';')) {
3035                                 /* we're in an inner scope and have a definition. Override
3036                                    existing definition in outer scope */
3037                                 compound = NULL;
3038                         } else if (compound->complete && token.type == '{') {
3039                                 assert(symbol != NULL);
3040                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition %P)",
3041                                        is_struct ? "struct" : "union", symbol,
3042                                        &compound->base.source_position);
3043                                 /* clear members in the hope to avoid further errors */
3044                                 compound->members.entities = NULL;
3045                         }
3046                 }
3047         } else if (token.type != '{') {
3048                 if (is_struct) {
3049                         parse_error_expected("while parsing struct type specifier",
3050                                              T_IDENTIFIER, '{', NULL);
3051                 } else {
3052                         parse_error_expected("while parsing union type specifier",
3053                                              T_IDENTIFIER, '{', NULL);
3054                 }
3055
3056                 return NULL;
3057         }
3058
3059         if (compound == NULL) {
3060                 entity_kind_t  kind   = is_struct ? ENTITY_STRUCT : ENTITY_UNION;
3061                 entity_t      *entity = allocate_entity_zero(kind);
3062                 compound              = &entity->compound;
3063
3064                 compound->base.namespc =
3065                         (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
3066                 compound->base.source_position = token.source_position;
3067                 compound->base.symbol          = symbol;
3068                 compound->base.parent_scope    = current_scope;
3069                 if (symbol != NULL) {
3070                         environment_push(entity);
3071                 }
3072                 append_entity(current_scope, entity);
3073         }
3074
3075         if (token.type == '{') {
3076                 parse_compound_type_entries(compound);
3077                 modifiers |= parse_attributes(&attributes);
3078
3079                 if (symbol == NULL) {
3080                         assert(anonymous_entity == NULL);
3081                         anonymous_entity = (entity_t*)compound;
3082                 }
3083         }
3084
3085         compound->modifiers |= modifiers;
3086         return compound;
3087 }
3088
3089 static void parse_enum_entries(type_t *const enum_type)
3090 {
3091         eat('{');
3092
3093         if (token.type == '}') {
3094                 errorf(HERE, "empty enum not allowed");
3095                 next_token();
3096                 return;
3097         }
3098
3099         add_anchor_token('}');
3100         do {
3101                 if (token.type != T_IDENTIFIER) {
3102                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
3103                         eat_block();
3104                         rem_anchor_token('}');
3105                         return;
3106                 }
3107
3108                 entity_t *entity             = allocate_entity_zero(ENTITY_ENUM_VALUE);
3109                 entity->enum_value.enum_type = enum_type;
3110                 entity->base.symbol          = token.v.symbol;
3111                 entity->base.source_position = token.source_position;
3112                 next_token();
3113
3114                 if (token.type == '=') {
3115                         next_token();
3116                         expression_t *value = parse_constant_expression();
3117
3118                         value = create_implicit_cast(value, enum_type);
3119                         entity->enum_value.value = value;
3120
3121                         /* TODO semantic */
3122                 }
3123
3124                 record_entity(entity, false);
3125
3126                 if (token.type != ',')
3127                         break;
3128                 next_token();
3129         } while (token.type != '}');
3130         rem_anchor_token('}');
3131
3132         expect('}', end_error);
3133
3134 end_error:
3135         ;
3136 }
3137
3138 static type_t *parse_enum_specifier(void)
3139 {
3140         gnu_attribute_t *attributes = NULL;
3141         entity_t        *entity;
3142         symbol_t        *symbol;
3143
3144         eat(T_enum);
3145         if (token.type == T_IDENTIFIER) {
3146                 symbol = token.v.symbol;
3147                 next_token();
3148
3149                 entity = get_entity(symbol, NAMESPACE_ENUM);
3150                 assert(entity == NULL || entity->kind == ENTITY_ENUM);
3151         } else if (token.type != '{') {
3152                 parse_error_expected("while parsing enum type specifier",
3153                                      T_IDENTIFIER, '{', NULL);
3154                 return NULL;
3155         } else {
3156                 entity  = NULL;
3157                 symbol  = NULL;
3158         }
3159
3160         if (entity == NULL) {
3161                 entity                       = allocate_entity_zero(ENTITY_ENUM);
3162                 entity->base.namespc         = NAMESPACE_ENUM;
3163                 entity->base.source_position = token.source_position;
3164                 entity->base.symbol          = symbol;
3165                 entity->base.parent_scope    = current_scope;
3166         }
3167
3168         type_t *const type = allocate_type_zero(TYPE_ENUM);
3169         type->enumt.enume  = &entity->enume;
3170
3171         if (token.type == '{') {
3172                 if (entity->enume.complete) {
3173                         errorf(HERE, "multiple definitions of 'enum %Y' (previous definition %P)",
3174                                symbol, &entity->base.source_position);
3175                 }
3176                 if (symbol != NULL) {
3177                         environment_push(entity);
3178                 }
3179                 append_entity(current_scope, entity);
3180                 entity->enume.complete = true;
3181
3182                 parse_enum_entries(type);
3183                 parse_attributes(&attributes);
3184
3185                 if (symbol == NULL) {
3186                         assert(anonymous_entity == NULL);
3187                         anonymous_entity = entity;
3188                 }
3189         } else if (!entity->enume.complete && !(c_mode & _GNUC)) {
3190                 errorf(HERE, "'enum %Y' used before definition (incomplete enums are a GNU extension)",
3191                        symbol);
3192         }
3193
3194         return type;
3195 }
3196
3197 /**
3198  * if a symbol is a typedef to another type, return true
3199  */
3200 static bool is_typedef_symbol(symbol_t *symbol)
3201 {
3202         const entity_t *const entity = get_entity(symbol, NAMESPACE_NORMAL);
3203         return entity != NULL && entity->kind == ENTITY_TYPEDEF;
3204 }
3205
3206 static type_t *parse_typeof(void)
3207 {
3208         eat(T___typeof__);
3209
3210         type_t *type;
3211
3212         expect('(', end_error);
3213         add_anchor_token(')');
3214
3215         expression_t *expression  = NULL;
3216
3217         bool old_type_prop     = in_type_prop;
3218         bool old_gcc_extension = in_gcc_extension;
3219         in_type_prop           = true;
3220
3221         while (token.type == T___extension__) {
3222                 /* This can be a prefix to a typename or an expression. */
3223                 next_token();
3224                 in_gcc_extension = true;
3225         }
3226         switch (token.type) {
3227         case T_IDENTIFIER:
3228                 if (is_typedef_symbol(token.v.symbol)) {
3229                         type = parse_typename();
3230                 } else {
3231                         expression = parse_expression();
3232                         type       = expression->base.type;
3233                 }
3234                 break;
3235
3236         TYPENAME_START
3237                 type = parse_typename();
3238                 break;
3239
3240         default:
3241                 expression = parse_expression();
3242                 type       = expression->base.type;
3243                 break;
3244         }
3245         in_type_prop     = old_type_prop;
3246         in_gcc_extension = old_gcc_extension;
3247
3248         rem_anchor_token(')');
3249         expect(')', end_error);
3250
3251         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF);
3252         typeof_type->typeoft.expression  = expression;
3253         typeof_type->typeoft.typeof_type = type;
3254
3255         return typeof_type;
3256 end_error:
3257         return NULL;
3258 }
3259
3260 typedef enum specifiers_t {
3261         SPECIFIER_SIGNED    = 1 << 0,
3262         SPECIFIER_UNSIGNED  = 1 << 1,
3263         SPECIFIER_LONG      = 1 << 2,
3264         SPECIFIER_INT       = 1 << 3,
3265         SPECIFIER_DOUBLE    = 1 << 4,
3266         SPECIFIER_CHAR      = 1 << 5,
3267         SPECIFIER_WCHAR_T   = 1 << 6,
3268         SPECIFIER_SHORT     = 1 << 7,
3269         SPECIFIER_LONG_LONG = 1 << 8,
3270         SPECIFIER_FLOAT     = 1 << 9,
3271         SPECIFIER_BOOL      = 1 << 10,
3272         SPECIFIER_VOID      = 1 << 11,
3273         SPECIFIER_INT8      = 1 << 12,
3274         SPECIFIER_INT16     = 1 << 13,
3275         SPECIFIER_INT32     = 1 << 14,
3276         SPECIFIER_INT64     = 1 << 15,
3277         SPECIFIER_INT128    = 1 << 16,
3278         SPECIFIER_COMPLEX   = 1 << 17,
3279         SPECIFIER_IMAGINARY = 1 << 18,
3280 } specifiers_t;
3281
3282 static type_t *create_builtin_type(symbol_t *const symbol,
3283                                    type_t *const real_type)
3284 {
3285         type_t *type            = allocate_type_zero(TYPE_BUILTIN);
3286         type->builtin.symbol    = symbol;
3287         type->builtin.real_type = real_type;
3288
3289         type_t *result = typehash_insert(type);
3290         if (type != result) {
3291                 free_type(type);
3292         }
3293
3294         return result;
3295 }
3296
3297 static type_t *get_typedef_type(symbol_t *symbol)
3298 {
3299         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
3300         if (entity == NULL || entity->kind != ENTITY_TYPEDEF)
3301                 return NULL;
3302
3303         type_t *type            = allocate_type_zero(TYPE_TYPEDEF);
3304         type->typedeft.typedefe = &entity->typedefe;
3305
3306         return type;
3307 }
3308
3309 /**
3310  * check for the allowed MS alignment values.
3311  */
3312 static bool check_alignment_value(long long intvalue)
3313 {
3314         if (intvalue < 1 || intvalue > 8192) {
3315                 errorf(HERE, "illegal alignment value");
3316                 return false;
3317         }
3318         unsigned v = (unsigned)intvalue;
3319         for (unsigned i = 1; i <= 8192; i += i) {
3320                 if (i == v)
3321                         return true;
3322         }
3323         errorf(HERE, "alignment must be power of two");
3324         return false;
3325 }
3326
3327 #define DET_MOD(name, tag) do { \
3328         if (*modifiers & tag && warning.other) warningf(HERE, #name " used more than once"); \
3329         *modifiers |= tag; \
3330 } while (0)
3331
3332 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
3333 {
3334         decl_modifiers_t *modifiers = &specifiers->modifiers;
3335
3336         while (true) {
3337                 if (token.type == T_restrict) {
3338                         next_token();
3339                         DET_MOD(restrict, DM_RESTRICT);
3340                         goto end_loop;
3341                 } else if (token.type != T_IDENTIFIER)
3342                         break;
3343                 symbol_t *symbol = token.v.symbol;
3344                 if (symbol == sym_align) {
3345                         next_token();
3346                         expect('(', end_error);
3347                         if (token.type != T_INTEGER)
3348                                 goto end_error;
3349                         if (check_alignment_value(token.v.intvalue)) {
3350                                 if (specifiers->alignment != 0 && warning.other)
3351                                         warningf(HERE, "align used more than once");
3352                                 specifiers->alignment = (unsigned char)token.v.intvalue;
3353                         }
3354                         next_token();
3355                         expect(')', end_error);
3356                 } else if (symbol == sym_allocate) {
3357                         next_token();
3358                         expect('(', end_error);
3359                         if (token.type != T_IDENTIFIER)
3360                                 goto end_error;
3361                         (void)token.v.symbol;
3362                         expect(')', end_error);
3363                 } else if (symbol == sym_dllimport) {
3364                         next_token();
3365                         DET_MOD(dllimport, DM_DLLIMPORT);
3366                 } else if (symbol == sym_dllexport) {
3367                         next_token();
3368                         DET_MOD(dllexport, DM_DLLEXPORT);
3369                 } else if (symbol == sym_thread) {
3370                         next_token();
3371                         DET_MOD(thread, DM_THREAD);
3372                 } else if (symbol == sym_naked) {
3373                         next_token();
3374                         DET_MOD(naked, DM_NAKED);
3375                 } else if (symbol == sym_noinline) {
3376                         next_token();
3377                         DET_MOD(noinline, DM_NOINLINE);
3378                 } else if (symbol == sym_returns_twice) {
3379                         next_token();
3380                         DET_MOD(returns_twice, DM_RETURNS_TWICE);
3381                 } else if (symbol == sym_noreturn) {
3382                         next_token();
3383                         DET_MOD(noreturn, DM_NORETURN);
3384                 } else if (symbol == sym_nothrow) {
3385                         next_token();
3386                         DET_MOD(nothrow, DM_NOTHROW);
3387                 } else if (symbol == sym_novtable) {
3388                         next_token();
3389                         DET_MOD(novtable, DM_NOVTABLE);
3390                 } else if (symbol == sym_property) {
3391                         next_token();
3392                         expect('(', end_error);
3393                         for (;;) {
3394                                 bool is_get = false;
3395                                 if (token.type != T_IDENTIFIER)
3396                                         goto end_error;
3397                                 if (token.v.symbol == sym_get) {
3398                                         is_get = true;
3399                                 } else if (token.v.symbol == sym_put) {
3400                                 } else {
3401                                         errorf(HERE, "Bad property name '%Y'", token.v.symbol);
3402                                         goto end_error;
3403                                 }
3404                                 next_token();
3405                                 expect('=', end_error);
3406                                 if (token.type != T_IDENTIFIER)
3407                                         goto end_error;
3408                                 if (is_get) {
3409                                         if (specifiers->get_property_sym != NULL) {
3410                                                 errorf(HERE, "get property name already specified");
3411                                         } else {
3412                                                 specifiers->get_property_sym = token.v.symbol;
3413                                         }
3414                                 } else {
3415                                         if (specifiers->put_property_sym != NULL) {
3416                                                 errorf(HERE, "put property name already specified");
3417                                         } else {
3418                                                 specifiers->put_property_sym = token.v.symbol;
3419                                         }
3420                                 }
3421                                 next_token();
3422                                 if (token.type == ',') {
3423                                         next_token();
3424                                         continue;
3425                                 }
3426                                 break;
3427                         }
3428                         expect(')', end_error);
3429                 } else if (symbol == sym_selectany) {
3430                         next_token();
3431                         DET_MOD(selectany, DM_SELECTANY);
3432                 } else if (symbol == sym_uuid) {
3433                         next_token();
3434                         expect('(', end_error);
3435                         if (token.type != T_STRING_LITERAL)
3436                                 goto end_error;
3437                         next_token();
3438                         expect(')', end_error);
3439                 } else if (symbol == sym_deprecated) {
3440                         next_token();
3441                         if (specifiers->deprecated != 0 && warning.other)
3442                                 warningf(HERE, "deprecated used more than once");
3443                         specifiers->deprecated = true;
3444                         if (token.type == '(') {
3445                                 next_token();
3446                                 if (token.type == T_STRING_LITERAL) {
3447                                         specifiers->deprecated_string = token.v.string.begin;
3448                                         next_token();
3449                                 } else {
3450                                         errorf(HERE, "string literal expected");
3451                                 }
3452                                 expect(')', end_error);
3453                         }
3454                 } else if (symbol == sym_noalias) {
3455                         next_token();
3456                         DET_MOD(noalias, DM_NOALIAS);
3457                 } else {
3458                         if (warning.other)
3459                                 warningf(HERE, "Unknown modifier '%Y' ignored", token.v.symbol);
3460                         next_token();
3461                         if (token.type == '(')
3462                                 skip_until(')');
3463                 }
3464 end_loop:
3465                 if (token.type == ',')
3466                         next_token();
3467         }
3468 end_error:
3469         return;
3470 }
3471
3472 static entity_t *create_error_entity(symbol_t *symbol, entity_kind_tag_t kind)
3473 {
3474         entity_t *entity             = allocate_entity_zero(kind);
3475         entity->base.source_position = *HERE;
3476         entity->base.symbol          = symbol;
3477         if (is_declaration(entity)) {
3478                 entity->declaration.type     = type_error_type;
3479                 entity->declaration.implicit = true;
3480         } else if (kind == ENTITY_TYPEDEF) {
3481                 entity->typedefe.type    = type_error_type;
3482                 entity->typedefe.builtin = true;
3483         }
3484         if (kind != ENTITY_COMPOUND_MEMBER)
3485                 record_entity(entity, false);
3486         return entity;
3487 }
3488
3489 static void parse_microsoft_based(based_spec_t *based_spec)
3490 {
3491         if (token.type != T_IDENTIFIER) {
3492                 parse_error_expected("while parsing __based", T_IDENTIFIER, NULL);
3493                 return;
3494         }
3495         symbol_t *symbol = token.v.symbol;
3496         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
3497
3498         if (entity == NULL || entity->base.kind != ENTITY_VARIABLE) {
3499                 errorf(HERE, "'%Y' is not a variable name.", symbol);
3500                 entity = create_error_entity(symbol, ENTITY_VARIABLE);
3501         } else {
3502                 variable_t *variable = &entity->variable;
3503
3504                 if (based_spec->base_variable != NULL) {
3505                         errorf(HERE, "__based type qualifier specified more than once");
3506                 }
3507                 based_spec->source_position = token.source_position;
3508                 based_spec->base_variable   = variable;
3509
3510                 type_t *const type = variable->base.type;
3511
3512                 if (is_type_valid(type)) {
3513                         if (! is_type_pointer(skip_typeref(type))) {
3514                                 errorf(HERE, "variable in __based modifier must have pointer type instead of '%T'", type);
3515                         }
3516                         if (variable->base.base.parent_scope != file_scope) {
3517                                 errorf(HERE, "a nonstatic local variable may not be used in a __based specification");
3518                         }
3519                 }
3520         }
3521         next_token();
3522 }
3523
3524 /**
3525  * Finish the construction of a struct type by calculating
3526  * its size, offsets, alignment.
3527  */
3528 static void finish_struct_type(compound_type_t *type)
3529 {
3530         assert(type->compound != NULL);
3531
3532         compound_t *compound = type->compound;
3533         if (!compound->complete)
3534                 return;
3535
3536         il_size_t      size           = 0;
3537         il_size_t      offset;
3538         il_alignment_t alignment      = 1;
3539         bool           need_pad       = false;
3540
3541         entity_t *entry = compound->members.entities;
3542         for (; entry != NULL; entry = entry->base.next) {
3543                 if (entry->kind != ENTITY_COMPOUND_MEMBER)
3544                         continue;
3545
3546                 type_t *m_type = skip_typeref(entry->declaration.type);
3547                 if (! is_type_valid(m_type)) {
3548                         /* simply ignore errors here */
3549                         continue;
3550                 }
3551                 il_alignment_t m_alignment = m_type->base.alignment;
3552                 if (m_alignment > alignment)
3553                         alignment = m_alignment;
3554
3555                 offset = (size + m_alignment - 1) & -m_alignment;
3556
3557                 if (offset > size)
3558                         need_pad = true;
3559                 entry->compound_member.offset = offset;
3560                 size = offset + m_type->base.size;
3561         }
3562         if (type->base.alignment != 0) {
3563                 alignment = type->base.alignment;
3564         }
3565
3566         offset = (size + alignment - 1) & -alignment;
3567         if (offset > size)
3568                 need_pad = true;
3569
3570         if (need_pad) {
3571                 if (warning.padded) {
3572                         warningf(&compound->base.source_position, "'%T' needs padding", type);
3573                 }
3574         } else {
3575                 if (compound->modifiers & DM_PACKED && warning.packed) {
3576                         warningf(&compound->base.source_position,
3577                                         "superfluous packed attribute on '%T'", type);
3578                 }
3579         }
3580
3581         type->base.size      = offset;
3582         type->base.alignment = alignment;
3583 }
3584
3585 /**
3586  * Finish the construction of an union type by calculating
3587  * its size and alignment.
3588  */
3589 static void finish_union_type(compound_type_t *type)
3590 {
3591         assert(type->compound != NULL);
3592
3593         compound_t *compound = type->compound;
3594         if (! compound->complete)
3595                 return;
3596
3597         il_size_t      size      = 0;
3598         il_alignment_t alignment = 1;
3599
3600         entity_t *entry = compound->members.entities;
3601         for (; entry != NULL; entry = entry->base.next) {
3602                 if (entry->kind != ENTITY_COMPOUND_MEMBER)
3603                         continue;
3604
3605                 type_t *m_type = skip_typeref(entry->declaration.type);
3606                 if (! is_type_valid(m_type))
3607                         continue;
3608
3609                 entry->compound_member.offset = 0;
3610                 if (m_type->base.size > size)
3611                         size = m_type->base.size;
3612                 if (m_type->base.alignment > alignment)
3613                         alignment = m_type->base.alignment;
3614         }
3615         if (type->base.alignment != 0) {
3616                 alignment = type->base.alignment;
3617         }
3618         size = (size + alignment - 1) & -alignment;
3619         type->base.size      = size;
3620         type->base.alignment = alignment;
3621 }
3622
3623 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
3624 {
3625         type_t            *type              = NULL;
3626         type_qualifiers_t  qualifiers        = TYPE_QUALIFIER_NONE;
3627         type_modifiers_t   modifiers         = TYPE_MODIFIER_NONE;
3628         unsigned           type_specifiers   = 0;
3629         bool               newtype           = false;
3630         bool               saw_error         = false;
3631         bool               old_gcc_extension = in_gcc_extension;
3632
3633         specifiers->source_position = token.source_position;
3634
3635         while (true) {
3636                 specifiers->modifiers
3637                         |= parse_attributes(&specifiers->gnu_attributes);
3638                 if (specifiers->modifiers & DM_TRANSPARENT_UNION)
3639                         modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3640
3641                 switch (token.type) {
3642                 /* storage class */
3643 #define MATCH_STORAGE_CLASS(token, class)                                  \
3644                 case token:                                                        \
3645                         if (specifiers->storage_class != STORAGE_CLASS_NONE) {         \
3646                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3647                         }                                                              \
3648                         specifiers->storage_class = class;                             \
3649                         if (specifiers->thread_local)                                  \
3650                                 goto check_thread_storage_class;                           \
3651                         next_token();                                                  \
3652                         break;
3653
3654                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3655                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3656                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3657                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3658                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3659
3660                 case T__declspec:
3661                         next_token();
3662                         expect('(', end_error);
3663                         add_anchor_token(')');
3664                         parse_microsoft_extended_decl_modifier(specifiers);
3665                         rem_anchor_token(')');
3666                         expect(')', end_error);
3667                         break;
3668
3669                 case T___thread:
3670                         if (specifiers->thread_local) {
3671                                 errorf(HERE, "duplicate '__thread'");
3672                         } else {
3673                                 specifiers->thread_local = true;
3674 check_thread_storage_class:
3675                                 switch (specifiers->storage_class) {
3676                                         case STORAGE_CLASS_EXTERN:
3677                                         case STORAGE_CLASS_NONE:
3678                                         case STORAGE_CLASS_STATIC:
3679                                                 break;
3680
3681                                                 char const* wrong;
3682                                         case STORAGE_CLASS_AUTO:     wrong = "auto";     goto wrong_thread_stoarge_class;
3683                                         case STORAGE_CLASS_REGISTER: wrong = "register"; goto wrong_thread_stoarge_class;
3684                                         case STORAGE_CLASS_TYPEDEF:  wrong = "typedef";  goto wrong_thread_stoarge_class;
3685 wrong_thread_stoarge_class:
3686                                                 errorf(HERE, "'__thread' used with '%s'", wrong);
3687                                                 break;
3688                                 }
3689                         }
3690                         next_token();
3691                         break;
3692
3693                 /* type qualifiers */
3694 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3695                 case token:                                                     \
3696                         qualifiers |= qualifier;                                    \
3697                         next_token();                                               \
3698                         break
3699
3700                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3701                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3702                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3703                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3704                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3705                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3706                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3707                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3708
3709                 case T___extension__:
3710                         next_token();
3711                         in_gcc_extension = true;
3712                         break;
3713
3714                 /* type specifiers */
3715 #define MATCH_SPECIFIER(token, specifier, name)                         \
3716                 case token:                                                     \
3717                         if (type_specifiers & specifier) {                           \
3718                                 errorf(HERE, "multiple " name " type specifiers given"); \
3719                         } else {                                                    \
3720                                 type_specifiers |= specifier;                           \
3721                         }                                                           \
3722                         next_token();                                               \
3723                         break
3724
3725                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3726                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3727                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3728                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3729                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3730                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3731                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3732                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3733                 MATCH_SPECIFIER(T_bool,       SPECIFIER_BOOL,      "bool");
3734                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3735                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3736                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3737                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3738                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3739                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3740                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3741                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3742                 MATCH_SPECIFIER(T_wchar_t,    SPECIFIER_WCHAR_T,   "wchar_t");
3743
3744                 case T__forceinline:
3745                         /* only in microsoft mode */
3746                         specifiers->modifiers |= DM_FORCEINLINE;
3747                         /* FALLTHROUGH */
3748
3749                 case T_inline:
3750                         next_token();
3751                         specifiers->is_inline = true;
3752                         break;
3753
3754                 case T_long:
3755                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3756                                 errorf(HERE, "multiple type specifiers given");
3757                         } else if (type_specifiers & SPECIFIER_LONG) {
3758                                 type_specifiers |= SPECIFIER_LONG_LONG;
3759                         } else {
3760                                 type_specifiers |= SPECIFIER_LONG;
3761                         }
3762                         next_token();
3763                         break;
3764
3765                 case T_struct: {
3766                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT);
3767
3768                         type->compound.compound = parse_compound_type_specifier(true);
3769                         finish_struct_type(&type->compound);
3770                         break;
3771                 }
3772                 case T_union: {
3773                         type = allocate_type_zero(TYPE_COMPOUND_UNION);
3774                         type->compound.compound = parse_compound_type_specifier(false);
3775                         if (type->compound.compound->modifiers & DM_TRANSPARENT_UNION)
3776                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3777                         finish_union_type(&type->compound);
3778                         break;
3779                 }
3780                 case T_enum:
3781                         type = parse_enum_specifier();
3782                         break;
3783                 case T___typeof__:
3784                         type = parse_typeof();
3785                         break;
3786                 case T___builtin_va_list:
3787                         type = duplicate_type(type_valist);
3788                         next_token();
3789                         break;
3790
3791                 case T_IDENTIFIER: {
3792                         /* only parse identifier if we haven't found a type yet */
3793                         if (type != NULL || type_specifiers != 0) {
3794                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
3795                                  * declaration, so it doesn't generate errors about expecting '(' or
3796                                  * '{' later on. */
3797                                 switch (look_ahead(1)->type) {
3798                                         STORAGE_CLASSES
3799                                         TYPE_SPECIFIERS
3800                                         case T_const:
3801                                         case T_restrict:
3802                                         case T_volatile:
3803                                         case T_inline:
3804                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
3805                                         case T_IDENTIFIER:
3806                                         case '&':
3807                                         case '*':
3808                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
3809                                                 next_token();
3810                                                 continue;
3811
3812                                         default:
3813                                                 goto finish_specifiers;
3814                                 }
3815                         }
3816
3817                         type_t *const typedef_type = get_typedef_type(token.v.symbol);
3818                         if (typedef_type == NULL) {
3819                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3820                                  * declaration, so it doesn't generate 'implicit int' followed by more
3821                                  * errors later on. */
3822                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3823                                 switch (la1_type) {
3824                                         DECLARATION_START
3825                                         case T_IDENTIFIER:
3826                                         case '&':
3827                                         case '*': {
3828                                                 errorf(HERE, "%K does not name a type", &token);
3829
3830                                                 entity_t *entity =
3831                                                         create_error_entity(token.v.symbol, ENTITY_TYPEDEF);
3832
3833                                                 type = allocate_type_zero(TYPE_TYPEDEF);
3834                                                 type->typedeft.typedefe = &entity->typedefe;
3835
3836                                                 next_token();
3837                                                 saw_error = true;
3838                                                 if (la1_type == '&' || la1_type == '*')
3839                                                         goto finish_specifiers;
3840                                                 continue;
3841                                         }
3842
3843                                         default:
3844                                                 goto finish_specifiers;
3845                                 }
3846                         }
3847
3848                         next_token();
3849                         type = typedef_type;
3850                         break;
3851                 }
3852
3853                 /* function specifier */
3854                 default:
3855                         goto finish_specifiers;
3856                 }
3857         }
3858
3859 finish_specifiers:
3860         in_gcc_extension = old_gcc_extension;
3861
3862         if (type == NULL || (saw_error && type_specifiers != 0)) {
3863                 atomic_type_kind_t atomic_type;
3864
3865                 /* match valid basic types */
3866                 switch (type_specifiers) {
3867                 case SPECIFIER_VOID:
3868                         atomic_type = ATOMIC_TYPE_VOID;
3869                         break;
3870                 case SPECIFIER_WCHAR_T:
3871                         atomic_type = ATOMIC_TYPE_WCHAR_T;
3872                         break;
3873                 case SPECIFIER_CHAR:
3874                         atomic_type = ATOMIC_TYPE_CHAR;
3875                         break;
3876                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3877                         atomic_type = ATOMIC_TYPE_SCHAR;
3878                         break;
3879                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3880                         atomic_type = ATOMIC_TYPE_UCHAR;
3881                         break;
3882                 case SPECIFIER_SHORT:
3883                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3884                 case SPECIFIER_SHORT | SPECIFIER_INT:
3885                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3886                         atomic_type = ATOMIC_TYPE_SHORT;
3887                         break;
3888                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3889                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3890                         atomic_type = ATOMIC_TYPE_USHORT;
3891                         break;
3892                 case SPECIFIER_INT:
3893                 case SPECIFIER_SIGNED:
3894                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3895                         atomic_type = ATOMIC_TYPE_INT;
3896                         break;
3897                 case SPECIFIER_UNSIGNED:
3898                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3899                         atomic_type = ATOMIC_TYPE_UINT;
3900                         break;
3901                 case SPECIFIER_LONG:
3902                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3903                 case SPECIFIER_LONG | SPECIFIER_INT:
3904                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3905                         atomic_type = ATOMIC_TYPE_LONG;
3906                         break;
3907                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3908                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3909                         atomic_type = ATOMIC_TYPE_ULONG;
3910                         break;
3911
3912                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3913                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3914                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3915                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3916                         | SPECIFIER_INT:
3917                         atomic_type = ATOMIC_TYPE_LONGLONG;
3918                         goto warn_about_long_long;
3919
3920                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3921                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3922                         | SPECIFIER_INT:
3923                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3924 warn_about_long_long:
3925                         if (warning.long_long) {
3926                                 warningf(&specifiers->source_position,
3927                                          "ISO C90 does not support 'long long'");
3928                         }
3929                         break;
3930
3931                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3932                         atomic_type = unsigned_int8_type_kind;
3933                         break;
3934
3935                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3936                         atomic_type = unsigned_int16_type_kind;
3937                         break;
3938
3939                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3940                         atomic_type = unsigned_int32_type_kind;
3941                         break;
3942
3943                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3944                         atomic_type = unsigned_int64_type_kind;
3945                         break;
3946
3947                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3948                         atomic_type = unsigned_int128_type_kind;
3949                         break;
3950
3951                 case SPECIFIER_INT8:
3952                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3953                         atomic_type = int8_type_kind;
3954                         break;
3955
3956                 case SPECIFIER_INT16:
3957                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3958                         atomic_type = int16_type_kind;
3959                         break;
3960
3961                 case SPECIFIER_INT32:
3962                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3963                         atomic_type = int32_type_kind;
3964                         break;
3965
3966                 case SPECIFIER_INT64:
3967                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3968                         atomic_type = int64_type_kind;
3969                         break;
3970
3971                 case SPECIFIER_INT128:
3972                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3973                         atomic_type = int128_type_kind;
3974                         break;
3975
3976                 case SPECIFIER_FLOAT:
3977                         atomic_type = ATOMIC_TYPE_FLOAT;
3978                         break;
3979                 case SPECIFIER_DOUBLE:
3980                         atomic_type = ATOMIC_TYPE_DOUBLE;
3981                         break;
3982                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3983                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3984                         break;
3985                 case SPECIFIER_BOOL:
3986                         atomic_type = ATOMIC_TYPE_BOOL;
3987                         break;
3988                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3989                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3990                         atomic_type = ATOMIC_TYPE_FLOAT;
3991                         break;
3992                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3993                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3994                         atomic_type = ATOMIC_TYPE_DOUBLE;
3995                         break;
3996                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3997                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3998                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3999                         break;
4000                 default:
4001                         /* invalid specifier combination, give an error message */
4002                         if (type_specifiers == 0) {
4003                                 if (saw_error)
4004                                         goto end_error;
4005
4006                                 /* ISO/IEC 14882:1998(E) §C.1.5:4 */
4007                                 if (!(c_mode & _CXX) && !strict_mode) {
4008                                         if (warning.implicit_int) {
4009                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
4010                                         }
4011                                         atomic_type = ATOMIC_TYPE_INT;
4012                                         break;
4013                                 } else {
4014                                         errorf(HERE, "no type specifiers given in declaration");
4015                                 }
4016                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
4017                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
4018                                 errorf(HERE, "signed and unsigned specifiers given");
4019                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
4020                                 errorf(HERE, "only integer types can be signed or unsigned");
4021                         } else {
4022                                 errorf(HERE, "multiple datatypes in declaration");
4023                         }
4024                         goto end_error;
4025                 }
4026
4027                 if (type_specifiers & SPECIFIER_COMPLEX) {
4028                         type                = allocate_type_zero(TYPE_COMPLEX);
4029                         type->complex.akind = atomic_type;
4030                 } else if (type_specifiers & SPECIFIER_IMAGINARY) {
4031                         type                  = allocate_type_zero(TYPE_IMAGINARY);
4032                         type->imaginary.akind = atomic_type;
4033                 } else {
4034                         type               = allocate_type_zero(TYPE_ATOMIC);
4035                         type->atomic.akind = atomic_type;
4036                 }
4037                 newtype = true;
4038         } else if (type_specifiers != 0) {
4039                 errorf(HERE, "multiple datatypes in declaration");
4040         }
4041
4042         /* FIXME: check type qualifiers here */
4043
4044         type->base.qualifiers = qualifiers;
4045         type->base.modifiers  = modifiers;
4046
4047         type_t *result = typehash_insert(type);
4048         if (newtype && result != type) {
4049                 free_type(type);
4050         }
4051
4052         specifiers->type = result;
4053         return;
4054
4055 end_error:
4056         specifiers->type = type_error_type;
4057         return;
4058 }
4059
4060 static type_qualifiers_t parse_type_qualifiers(void)
4061 {
4062         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
4063
4064         while (true) {
4065                 switch (token.type) {
4066                 /* type qualifiers */
4067                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
4068                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
4069                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
4070                 /* microsoft extended type modifiers */
4071                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
4072                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
4073                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
4074                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
4075                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
4076
4077                 default:
4078                         return qualifiers;
4079                 }
4080         }
4081 }
4082
4083 /**
4084  * Parses an K&R identifier list
4085  */
4086 static void parse_identifier_list(scope_t *scope)
4087 {
4088         do {
4089                 entity_t *entity = allocate_entity_zero(ENTITY_PARAMETER);
4090                 entity->base.source_position = token.source_position;
4091                 entity->base.namespc         = NAMESPACE_NORMAL;
4092                 entity->base.symbol          = token.v.symbol;
4093                 /* a K&R parameter has no type, yet */
4094                 next_token();
4095
4096                 if (scope != NULL)
4097                         append_entity(scope, entity);
4098
4099                 if (token.type != ',') {
4100                         break;
4101                 }
4102                 next_token();
4103         } while (token.type == T_IDENTIFIER);
4104 }
4105
4106 static entity_t *parse_parameter(void)
4107 {
4108         declaration_specifiers_t specifiers;
4109         memset(&specifiers, 0, sizeof(specifiers));
4110
4111         parse_declaration_specifiers(&specifiers);
4112
4113         entity_t *entity = parse_declarator(&specifiers,
4114                         DECL_MAY_BE_ABSTRACT | DECL_IS_PARAMETER);
4115         anonymous_entity = NULL;
4116         return entity;
4117 }
4118
4119 static void semantic_parameter_incomplete(const entity_t *entity)
4120 {
4121         assert(entity->kind == ENTITY_PARAMETER);
4122
4123         /* §6.7.5.3:4  After adjustment, the parameters in a parameter type
4124          *             list in a function declarator that is part of a
4125          *             definition of that function shall not have
4126          *             incomplete type. */
4127         type_t *type = skip_typeref(entity->declaration.type);
4128         if (is_type_incomplete(type)) {
4129                 errorf(&entity->base.source_position,
4130                        "parameter '%Y' has incomplete type '%T'", entity->base.symbol,
4131                        entity->declaration.type);
4132         }
4133 }
4134
4135 /**
4136  * Parses function type parameters (and optionally creates variable_t entities
4137  * for them in a scope)
4138  */
4139 static void parse_parameters(function_type_t *type, scope_t *scope)
4140 {
4141         eat('(');
4142         add_anchor_token(')');
4143         int saved_comma_state = save_and_reset_anchor_state(',');
4144
4145         if (token.type == T_IDENTIFIER &&
4146             !is_typedef_symbol(token.v.symbol)) {
4147                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
4148                 if (la1_type == ',' || la1_type == ')') {
4149                         type->kr_style_parameters    = true;
4150                         type->unspecified_parameters = true;
4151                         parse_identifier_list(scope);
4152                         goto parameters_finished;
4153                 }
4154         }
4155
4156         if (token.type == ')') {
4157                 /* ISO/IEC 14882:1998(E) §C.1.6:1 */
4158                 if (!(c_mode & _CXX))
4159                         type->unspecified_parameters = true;
4160                 goto parameters_finished;
4161         }
4162
4163         function_parameter_t *parameter;
4164         function_parameter_t *last_parameter = NULL;
4165
4166         while (true) {
4167                 switch (token.type) {
4168                 case T_DOTDOTDOT:
4169                         next_token();
4170                         type->variadic = true;
4171                         goto parameters_finished;
4172
4173                 case T_IDENTIFIER:
4174                 case T___extension__:
4175                 DECLARATION_START
4176                 {
4177                         entity_t *entity = parse_parameter();
4178                         if (entity->kind == ENTITY_TYPEDEF) {
4179                                 errorf(&entity->base.source_position,
4180                                        "typedef not allowed as function parameter");
4181                                 break;
4182                         }
4183                         assert(is_declaration(entity));
4184
4185                         /* func(void) is not a parameter */
4186                         if (last_parameter == NULL
4187                                         && token.type == ')'
4188                                         && entity->base.symbol == NULL
4189                                         && skip_typeref(entity->declaration.type) == type_void) {
4190                                 goto parameters_finished;
4191                         }
4192                         semantic_parameter_incomplete(entity);
4193
4194                         parameter = obstack_alloc(type_obst, sizeof(parameter[0]));
4195                         memset(parameter, 0, sizeof(parameter[0]));
4196                         parameter->type = entity->declaration.type;
4197
4198                         if (scope != NULL) {
4199                                 append_entity(scope, entity);
4200                         }
4201
4202                         if (last_parameter != NULL) {
4203                                 last_parameter->next = parameter;
4204                         } else {
4205                                 type->parameters = parameter;
4206                         }
4207                         last_parameter   = parameter;
4208                         break;
4209                 }
4210
4211                 default:
4212                         goto parameters_finished;
4213                 }
4214                 if (token.type != ',') {
4215                         goto parameters_finished;
4216                 }
4217                 next_token();
4218         }
4219
4220
4221 parameters_finished:
4222         rem_anchor_token(')');
4223         expect(')', end_error);
4224
4225 end_error:
4226         restore_anchor_state(',', saved_comma_state);
4227 }
4228
4229 typedef enum construct_type_kind_t {
4230         CONSTRUCT_INVALID,
4231         CONSTRUCT_POINTER,
4232         CONSTRUCT_REFERENCE,
4233         CONSTRUCT_FUNCTION,
4234         CONSTRUCT_ARRAY
4235 } construct_type_kind_t;
4236
4237 typedef struct construct_type_t construct_type_t;
4238 struct construct_type_t {
4239         construct_type_kind_t  kind;
4240         construct_type_t      *next;
4241 };
4242
4243 typedef struct parsed_pointer_t parsed_pointer_t;
4244 struct parsed_pointer_t {
4245         construct_type_t  construct_type;
4246         type_qualifiers_t type_qualifiers;
4247         variable_t        *base_variable;  /**< MS __based extension. */
4248 };
4249
4250 typedef struct parsed_reference_t parsed_reference_t;
4251 struct parsed_reference_t {
4252         construct_type_t construct_type;
4253 };
4254
4255 typedef struct construct_function_type_t construct_function_type_t;
4256 struct construct_function_type_t {
4257         construct_type_t  construct_type;
4258         type_t           *function_type;
4259 };
4260
4261 typedef struct parsed_array_t parsed_array_t;
4262 struct parsed_array_t {
4263         construct_type_t  construct_type;
4264         type_qualifiers_t type_qualifiers;
4265         bool              is_static;
4266         bool              is_variable;
4267         expression_t     *size;
4268 };
4269
4270 typedef struct construct_base_type_t construct_base_type_t;
4271 struct construct_base_type_t {
4272         construct_type_t  construct_type;
4273         type_t           *type;
4274 };
4275
4276 static construct_type_t *parse_pointer_declarator(variable_t *base_variable)
4277 {
4278         eat('*');
4279
4280         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
4281         memset(pointer, 0, sizeof(pointer[0]));
4282         pointer->construct_type.kind = CONSTRUCT_POINTER;
4283         pointer->type_qualifiers     = parse_type_qualifiers();
4284         pointer->base_variable       = base_variable;
4285
4286         return &pointer->construct_type;
4287 }
4288
4289 static construct_type_t *parse_reference_declarator(void)
4290 {
4291         eat('&');
4292
4293         parsed_reference_t *reference = obstack_alloc(&temp_obst, sizeof(reference[0]));
4294         memset(reference, 0, sizeof(reference[0]));
4295         reference->construct_type.kind = CONSTRUCT_REFERENCE;
4296
4297         return (construct_type_t*)reference;
4298 }
4299
4300 static construct_type_t *parse_array_declarator(void)
4301 {
4302         eat('[');
4303         add_anchor_token(']');
4304
4305         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
4306         memset(array, 0, sizeof(array[0]));
4307         array->construct_type.kind = CONSTRUCT_ARRAY;
4308
4309         if (token.type == T_static) {
4310                 array->is_static = true;
4311                 next_token();
4312         }
4313
4314         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
4315         if (type_qualifiers != 0) {
4316                 if (token.type == T_static) {
4317                         array->is_static = true;
4318                         next_token();
4319                 }
4320         }
4321         array->type_qualifiers = type_qualifiers;
4322
4323         if (token.type == '*' && look_ahead(1)->type == ']') {
4324                 array->is_variable = true;
4325                 next_token();
4326         } else if (token.type != ']') {
4327                 expression_t *const size = parse_assignment_expression();
4328                 array->size = size;
4329                 mark_vars_read(size, NULL);
4330         }
4331
4332         rem_anchor_token(']');
4333         expect(']', end_error);
4334
4335 end_error:
4336         return &array->construct_type;
4337 }
4338
4339 static construct_type_t *parse_function_declarator(scope_t *scope,
4340                                                    decl_modifiers_t modifiers)
4341 {
4342         type_t          *type  = allocate_type_zero(TYPE_FUNCTION);
4343         function_type_t *ftype = &type->function;
4344
4345         ftype->linkage = current_linkage;
4346
4347         switch (modifiers & (DM_CDECL | DM_STDCALL | DM_FASTCALL | DM_THISCALL)) {
4348                 case DM_NONE:     break;
4349                 case DM_CDECL:    ftype->calling_convention = CC_CDECL;    break;
4350                 case DM_STDCALL:  ftype->calling_convention = CC_STDCALL;  break;
4351                 case DM_FASTCALL: ftype->calling_convention = CC_FASTCALL; break;
4352                 case DM_THISCALL: ftype->calling_convention = CC_THISCALL; break;
4353
4354                 default:
4355                         errorf(HERE, "multiple calling conventions in declaration");
4356                         break;
4357         }
4358
4359         parse_parameters(ftype, scope);
4360
4361         construct_function_type_t *construct_function_type =
4362                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
4363         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
4364         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
4365         construct_function_type->function_type       = type;
4366
4367         return &construct_function_type->construct_type;
4368 }
4369
4370 typedef struct parse_declarator_env_t {
4371         decl_modifiers_t   modifiers;
4372         symbol_t          *symbol;
4373         source_position_t  source_position;
4374         scope_t            parameters;
4375 } parse_declarator_env_t;
4376
4377 static construct_type_t *parse_inner_declarator(parse_declarator_env_t *env,
4378                 bool may_be_abstract)
4379 {
4380         /* construct a single linked list of construct_type_t's which describe
4381          * how to construct the final declarator type */
4382         construct_type_t *first      = NULL;
4383         construct_type_t *last       = NULL;
4384         gnu_attribute_t  *attributes = NULL;
4385
4386         decl_modifiers_t modifiers = parse_attributes(&attributes);
4387
4388         /* MS __based extension */
4389         based_spec_t base_spec;
4390         base_spec.base_variable = NULL;
4391
4392         for (;;) {
4393                 construct_type_t *type;
4394                 switch (token.type) {
4395                         case '&':
4396                                 if (!(c_mode & _CXX))
4397                                         errorf(HERE, "references are only available for C++");
4398                                 if (base_spec.base_variable != NULL && warning.other) {
4399                                         warningf(&base_spec.source_position,
4400                                                  "__based does not precede a pointer operator, ignored");
4401                                 }
4402                                 type = parse_reference_declarator();
4403                                 /* consumed */
4404                                 base_spec.base_variable = NULL;
4405                                 break;
4406
4407                         case '*':
4408                                 type = parse_pointer_declarator(base_spec.base_variable);
4409                                 /* consumed */
4410                                 base_spec.base_variable = NULL;
4411                                 break;
4412
4413                         case T__based:
4414                                 next_token();
4415                                 expect('(', end_error);
4416                                 add_anchor_token(')');
4417                                 parse_microsoft_based(&base_spec);
4418                                 rem_anchor_token(')');
4419                                 expect(')', end_error);
4420                                 continue;
4421
4422                         default:
4423                                 goto ptr_operator_end;
4424                 }
4425
4426                 if (last == NULL) {
4427                         first = type;
4428                         last  = type;
4429                 } else {
4430                         last->next = type;
4431                         last       = type;
4432                 }
4433
4434                 /* TODO: find out if this is correct */
4435                 modifiers |= parse_attributes(&attributes);
4436         }
4437 ptr_operator_end:
4438         if (base_spec.base_variable != NULL && warning.other) {
4439                 warningf(&base_spec.source_position,
4440                          "__based does not precede a pointer operator, ignored");
4441         }
4442
4443         if (env != NULL) {
4444                 modifiers      |= env->modifiers;
4445                 env->modifiers  = modifiers;
4446         }
4447
4448         construct_type_t *inner_types = NULL;
4449
4450         switch (token.type) {
4451         case T_IDENTIFIER:
4452                 if (env == NULL) {
4453                         errorf(HERE, "no identifier expected in typename");
4454                 } else {
4455                         env->symbol          = token.v.symbol;
4456                         env->source_position = token.source_position;
4457                 }
4458                 next_token();
4459                 break;
4460         case '(':
4461                 /* §6.7.6:2 footnote 126:  Empty parentheses in a type name are
4462                  * interpreted as ``function with no parameter specification'', rather
4463                  * than redundant parentheses around the omitted identifier. */
4464                 if (look_ahead(1)->type != ')') {
4465                         next_token();
4466                         add_anchor_token(')');
4467                         inner_types = parse_inner_declarator(env, may_be_abstract);
4468                         if (inner_types != NULL) {
4469                                 /* All later declarators only modify the return type */
4470                                 env = NULL;
4471                         }
4472                         rem_anchor_token(')');
4473                         expect(')', end_error);
4474                 }
4475                 break;
4476         default:
4477                 if (may_be_abstract)
4478                         break;
4479                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
4480                 eat_until_anchor();
4481                 return NULL;
4482         }
4483
4484         construct_type_t *p = last;
4485
4486         while (true) {
4487                 construct_type_t *type;
4488                 switch (token.type) {
4489                 case '(': {
4490                         scope_t *scope = NULL;
4491                         if (env != NULL)
4492                                 scope = &env->parameters;
4493
4494                         type = parse_function_declarator(scope, modifiers);
4495                         break;
4496                 }
4497                 case '[':
4498                         type = parse_array_declarator();
4499                         break;
4500                 default:
4501                         goto declarator_finished;
4502                 }
4503
4504                 /* insert in the middle of the list (behind p) */
4505                 if (p != NULL) {
4506                         type->next = p->next;
4507                         p->next    = type;
4508                 } else {
4509                         type->next = first;
4510                         first      = type;
4511                 }
4512                 if (last == p) {
4513                         last = type;
4514                 }
4515         }
4516
4517 declarator_finished:
4518         /* append inner_types at the end of the list, we don't to set last anymore
4519          * as it's not needed anymore */
4520         if (last == NULL) {
4521                 assert(first == NULL);
4522                 first = inner_types;
4523         } else {
4524                 last->next = inner_types;
4525         }
4526
4527         return first;
4528 end_error:
4529         return NULL;
4530 }
4531
4532 static void parse_declaration_attributes(entity_t *entity)
4533 {
4534         gnu_attribute_t  *attributes = NULL;
4535         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
4536
4537         if (entity == NULL)
4538                 return;
4539
4540         type_t *type;
4541         if (entity->kind == ENTITY_TYPEDEF) {
4542                 modifiers |= entity->typedefe.modifiers;
4543                 type       = entity->typedefe.type;
4544         } else {
4545                 assert(is_declaration(entity));
4546                 modifiers |= entity->declaration.modifiers;
4547                 type       = entity->declaration.type;
4548         }
4549         if (type == NULL)
4550                 return;
4551
4552         /* handle these strange/stupid mode attributes */
4553         gnu_attribute_t *attribute = attributes;
4554         for ( ; attribute != NULL; attribute = attribute->next) {
4555                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
4556                         continue;
4557
4558                 atomic_type_kind_t  akind = attribute->u.akind;
4559                 if (!is_type_signed(type)) {
4560                         switch (akind) {
4561                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
4562                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
4563                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
4564                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
4565                         default:
4566                                 panic("invalid akind in mode attribute");
4567                         }
4568                 } else {
4569                         switch (akind) {
4570                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_SCHAR; break;
4571                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_SHORT; break;
4572                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_INT; break;
4573                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_LONGLONG; break;
4574                         default:
4575                                 panic("invalid akind in mode attribute");
4576                         }
4577                 }
4578
4579                 type = make_atomic_type(akind, type->base.qualifiers);
4580         }
4581
4582         type_modifiers_t type_modifiers = type->base.modifiers;
4583         if (modifiers & DM_TRANSPARENT_UNION)
4584                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
4585
4586         if (type->base.modifiers != type_modifiers) {
4587                 type_t *copy = duplicate_type(type);
4588                 copy->base.modifiers = type_modifiers;
4589
4590                 type = typehash_insert(copy);
4591                 if (type != copy) {
4592                         obstack_free(type_obst, copy);
4593                 }
4594         }
4595
4596         if (entity->kind == ENTITY_TYPEDEF) {
4597                 entity->typedefe.type      = type;
4598                 entity->typedefe.modifiers = modifiers;
4599         } else {
4600                 entity->declaration.type      = type;
4601                 entity->declaration.modifiers = modifiers;
4602         }
4603 }
4604
4605 static type_t *construct_declarator_type(construct_type_t *construct_list, type_t *type)
4606 {
4607         construct_type_t *iter = construct_list;
4608         for (; iter != NULL; iter = iter->next) {
4609                 switch (iter->kind) {
4610                 case CONSTRUCT_INVALID:
4611                         internal_errorf(HERE, "invalid type construction found");
4612                 case CONSTRUCT_FUNCTION: {
4613                         construct_function_type_t *construct_function_type
4614                                 = (construct_function_type_t*) iter;
4615
4616                         type_t *function_type = construct_function_type->function_type;
4617
4618                         function_type->function.return_type = type;
4619
4620                         type_t *skipped_return_type = skip_typeref(type);
4621                         /* §6.7.5.3(1) */
4622                         if (is_type_function(skipped_return_type)) {
4623                                 errorf(HERE, "function returning function is not allowed");
4624                         } else if (is_type_array(skipped_return_type)) {
4625                                 errorf(HERE, "function returning array is not allowed");
4626                         } else {
4627                                 if (skipped_return_type->base.qualifiers != 0 && warning.other) {
4628                                         warningf(HERE,
4629                                                 "type qualifiers in return type of function type are meaningless");
4630                                 }
4631                         }
4632
4633                         type = function_type;
4634                         break;
4635                 }
4636
4637                 case CONSTRUCT_POINTER: {
4638                         if (is_type_reference(skip_typeref(type)))
4639                                 errorf(HERE, "cannot declare a pointer to reference");
4640
4641                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
4642                         type = make_based_pointer_type(type, parsed_pointer->type_qualifiers, parsed_pointer->base_variable);
4643                         continue;
4644                 }
4645
4646                 case CONSTRUCT_REFERENCE:
4647                         if (is_type_reference(skip_typeref(type)))
4648                                 errorf(HERE, "cannot declare a reference to reference");
4649
4650                         type = make_reference_type(type);
4651                         continue;
4652
4653                 case CONSTRUCT_ARRAY: {
4654                         if (is_type_reference(skip_typeref(type)))
4655                                 errorf(HERE, "cannot declare an array of references");
4656
4657                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
4658                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY);
4659
4660                         expression_t *size_expression = parsed_array->size;
4661                         if (size_expression != NULL) {
4662                                 size_expression
4663                                         = create_implicit_cast(size_expression, type_size_t);
4664                         }
4665
4666                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
4667                         array_type->array.element_type    = type;
4668                         array_type->array.is_static       = parsed_array->is_static;
4669                         array_type->array.is_variable     = parsed_array->is_variable;
4670                         array_type->array.size_expression = size_expression;
4671
4672                         if (size_expression != NULL) {
4673                                 if (is_constant_expression(size_expression)) {
4674                                         array_type->array.size_constant = true;
4675                                         array_type->array.size
4676                                                 = fold_constant(size_expression);
4677                                 } else {
4678                                         array_type->array.is_vla = true;
4679                                 }
4680                         }
4681
4682                         type_t *skipped_type = skip_typeref(type);
4683                         /* §6.7.5.2(1) */
4684                         if (is_type_incomplete(skipped_type)) {
4685                                 errorf(HERE, "array of incomplete type '%T' is not allowed", type);
4686                         } else if (is_type_function(skipped_type)) {
4687                                 errorf(HERE, "array of functions is not allowed");
4688                         }
4689                         type = array_type;
4690                         break;
4691                 }
4692                 }
4693
4694                 type_t *hashed_type = typehash_insert(type);
4695                 if (hashed_type != type) {
4696                         /* the function type was constructed earlier freeing it here will
4697                          * destroy other types... */
4698                         if (iter->kind != CONSTRUCT_FUNCTION) {
4699                                 free_type(type);
4700                         }
4701                         type = hashed_type;
4702                 }
4703         }
4704
4705         return type;
4706 }
4707
4708 static type_t *automatic_type_conversion(type_t *orig_type);
4709
4710 static type_t *semantic_parameter(const source_position_t *pos,
4711                                   type_t *type,
4712                                   const declaration_specifiers_t *specifiers,
4713                                   symbol_t *symbol)
4714 {
4715         /* §6.7.5.3:7  A declaration of a parameter as ``array of type''
4716          *             shall be adjusted to ``qualified pointer to type'',
4717          *             [...]
4718          * §6.7.5.3:8  A declaration of a parameter as ``function returning
4719          *             type'' shall be adjusted to ``pointer to function
4720          *             returning type'', as in 6.3.2.1. */
4721         type = automatic_type_conversion(type);
4722
4723         if (specifiers->is_inline && is_type_valid(type)) {
4724                 errorf(pos, "parameter '%Y' declared 'inline'", symbol);
4725         }
4726
4727         /* §6.9.1:6  The declarations in the declaration list shall contain
4728          *           no storage-class specifier other than register and no
4729          *           initializations. */
4730         if (specifiers->thread_local || (
4731                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4732                         specifiers->storage_class != STORAGE_CLASS_REGISTER)
4733            ) {
4734                 errorf(pos, "invalid storage class for parameter '%Y'", symbol);
4735         }
4736
4737         /* delay test for incomplete type, because we might have (void)
4738          * which is legal but incomplete... */
4739
4740         return type;
4741 }
4742
4743 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
4744                                   declarator_flags_t flags)
4745 {
4746         parse_declarator_env_t env;
4747         memset(&env, 0, sizeof(env));
4748         env.modifiers = specifiers->modifiers;
4749
4750         construct_type_t *construct_type =
4751                 parse_inner_declarator(&env, (flags & DECL_MAY_BE_ABSTRACT) != 0);
4752         type_t           *orig_type      =
4753                 construct_declarator_type(construct_type, specifiers->type);
4754         type_t           *type           = skip_typeref(orig_type);
4755
4756         if (construct_type != NULL) {
4757                 obstack_free(&temp_obst, construct_type);
4758         }
4759
4760         entity_t *entity;
4761         if (specifiers->storage_class == STORAGE_CLASS_TYPEDEF) {
4762                 entity                       = allocate_entity_zero(ENTITY_TYPEDEF);
4763                 entity->base.symbol          = env.symbol;
4764                 entity->base.source_position = env.source_position;
4765                 entity->typedefe.type        = orig_type;
4766
4767                 if (anonymous_entity != NULL) {
4768                         if (is_type_compound(type)) {
4769                                 assert(anonymous_entity->compound.alias == NULL);
4770                                 assert(anonymous_entity->kind == ENTITY_STRUCT ||
4771                                        anonymous_entity->kind == ENTITY_UNION);
4772                                 anonymous_entity->compound.alias = entity;
4773                                 anonymous_entity = NULL;
4774                         } else if (is_type_enum(type)) {
4775                                 assert(anonymous_entity->enume.alias == NULL);
4776                                 assert(anonymous_entity->kind == ENTITY_ENUM);
4777                                 anonymous_entity->enume.alias = entity;
4778                                 anonymous_entity = NULL;
4779                         }
4780                 }
4781         } else {
4782                 /* create a declaration type entity */
4783                 if (flags & DECL_CREATE_COMPOUND_MEMBER) {
4784                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
4785
4786                         if (env.symbol != NULL) {
4787                                 if (specifiers->is_inline && is_type_valid(type)) {
4788                                         errorf(&env.source_position,
4789                                                         "compound member '%Y' declared 'inline'", env.symbol);
4790                                 }
4791
4792                                 if (specifiers->thread_local ||
4793                                                 specifiers->storage_class != STORAGE_CLASS_NONE) {
4794                                         errorf(&env.source_position,
4795                                                         "compound member '%Y' must have no storage class",
4796                                                         env.symbol);
4797                                 }
4798                         }
4799                 } else if (flags & DECL_IS_PARAMETER) {
4800                         orig_type = semantic_parameter(&env.source_position, orig_type,
4801                                                        specifiers, env.symbol);
4802
4803                         entity = allocate_entity_zero(ENTITY_PARAMETER);
4804                 } else if (is_type_function(type)) {
4805                         entity = allocate_entity_zero(ENTITY_FUNCTION);
4806
4807                         entity->function.is_inline  = specifiers->is_inline;
4808                         entity->function.parameters = env.parameters;
4809
4810                         if (env.symbol != NULL) {
4811                                 if (specifiers->thread_local || (
4812                                                         specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4813                                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4814                                                         specifiers->storage_class != STORAGE_CLASS_STATIC
4815                                                 )) {
4816                                         errorf(&env.source_position,
4817                                                         "invalid storage class for function '%Y'", env.symbol);
4818                                 }
4819                         }
4820                 } else {
4821                         entity = allocate_entity_zero(ENTITY_VARIABLE);
4822
4823                         entity->variable.get_property_sym = specifiers->get_property_sym;
4824                         entity->variable.put_property_sym = specifiers->put_property_sym;
4825                         if (specifiers->alignment != 0) {
4826                                 /* TODO: add checks here */
4827                                 entity->variable.alignment = specifiers->alignment;
4828                         }
4829
4830                         entity->variable.thread_local = specifiers->thread_local;
4831
4832                         if (env.symbol != NULL) {
4833                                 if (specifiers->is_inline && is_type_valid(type)) {
4834                                         errorf(&env.source_position,
4835                                                         "variable '%Y' declared 'inline'", env.symbol);
4836                                 }
4837
4838                                 bool invalid_storage_class = false;
4839                                 if (current_scope == file_scope) {
4840                                         if (specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4841                                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4842                                                         specifiers->storage_class != STORAGE_CLASS_STATIC) {
4843                                                 invalid_storage_class = true;
4844                                         }
4845                                 } else {
4846                                         if (specifiers->thread_local &&
4847                                                         specifiers->storage_class == STORAGE_CLASS_NONE) {
4848                                                 invalid_storage_class = true;
4849                                         }
4850                                 }
4851                                 if (invalid_storage_class) {
4852                                         errorf(&env.source_position,
4853                                                         "invalid storage class for variable '%Y'", env.symbol);
4854                                 }
4855                         }
4856                 }
4857
4858                 if (env.symbol != NULL) {
4859                         entity->base.symbol          = env.symbol;
4860                         entity->base.source_position = env.source_position;
4861                 } else {
4862                         entity->base.source_position = specifiers->source_position;
4863                 }
4864                 entity->base.namespc                  = NAMESPACE_NORMAL;
4865                 entity->declaration.type              = orig_type;
4866                 entity->declaration.modifiers         = env.modifiers;
4867                 entity->declaration.deprecated_string = specifiers->deprecated_string;
4868
4869                 storage_class_t storage_class = specifiers->storage_class;
4870                 entity->declaration.declared_storage_class = storage_class;
4871
4872                 if (storage_class == STORAGE_CLASS_NONE && current_scope != file_scope)
4873                         storage_class = STORAGE_CLASS_AUTO;
4874                 entity->declaration.storage_class = storage_class;
4875         }
4876
4877         parse_declaration_attributes(entity);
4878
4879         return entity;
4880 }
4881
4882 static type_t *parse_abstract_declarator(type_t *base_type)
4883 {
4884         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4885
4886         type_t *result = construct_declarator_type(construct_type, base_type);
4887         if (construct_type != NULL) {
4888                 obstack_free(&temp_obst, construct_type);
4889         }
4890
4891         return result;
4892 }
4893
4894 /**
4895  * Check if the declaration of main is suspicious.  main should be a
4896  * function with external linkage, returning int, taking either zero
4897  * arguments, two, or three arguments of appropriate types, ie.
4898  *
4899  * int main([ int argc, char **argv [, char **env ] ]).
4900  *
4901  * @param decl    the declaration to check
4902  * @param type    the function type of the declaration
4903  */
4904 static void check_type_of_main(const entity_t *entity)
4905 {
4906         const source_position_t *pos = &entity->base.source_position;
4907         if (entity->kind != ENTITY_FUNCTION) {
4908                 warningf(pos, "'main' is not a function");
4909                 return;
4910         }
4911
4912         if (entity->declaration.storage_class == STORAGE_CLASS_STATIC) {
4913                 warningf(pos, "'main' is normally a non-static function");
4914         }
4915
4916         type_t *type = skip_typeref(entity->declaration.type);
4917         assert(is_type_function(type));
4918
4919         function_type_t *func_type = &type->function;
4920         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4921                 warningf(pos, "return type of 'main' should be 'int', but is '%T'",
4922                          func_type->return_type);
4923         }
4924         const function_parameter_t *parm = func_type->parameters;
4925         if (parm != NULL) {
4926                 type_t *const first_type = parm->type;
4927                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4928                         warningf(pos,
4929                                  "first argument of 'main' should be 'int', but is '%T'",
4930                                  first_type);
4931                 }
4932                 parm = parm->next;
4933                 if (parm != NULL) {
4934                         type_t *const second_type = parm->type;
4935                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4936                                 warningf(pos, "second argument of 'main' should be 'char**', but is '%T'", second_type);
4937                         }
4938                         parm = parm->next;
4939                         if (parm != NULL) {
4940                                 type_t *const third_type = parm->type;
4941                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4942                                         warningf(pos, "third argument of 'main' should be 'char**', but is '%T'", third_type);
4943                                 }
4944                                 parm = parm->next;
4945                                 if (parm != NULL)
4946                                         goto warn_arg_count;
4947                         }
4948                 } else {
4949 warn_arg_count:
4950                         warningf(pos, "'main' takes only zero, two or three arguments");
4951                 }
4952         }
4953 }
4954
4955 /**
4956  * Check if a symbol is the equal to "main".
4957  */
4958 static bool is_sym_main(const symbol_t *const sym)
4959 {
4960         return strcmp(sym->string, "main") == 0;
4961 }
4962
4963 static void error_redefined_as_different_kind(const source_position_t *pos,
4964                 const entity_t *old, entity_kind_t new_kind)
4965 {
4966         errorf(pos, "redeclaration of %s '%Y' as %s (declared %P)",
4967                get_entity_kind_name(old->kind), old->base.symbol,
4968                get_entity_kind_name(new_kind), &old->base.source_position);
4969 }
4970
4971 /**
4972  * record entities for the NAMESPACE_NORMAL, and produce error messages/warnings
4973  * for various problems that occur for multiple definitions
4974  */
4975 static entity_t *record_entity(entity_t *entity, const bool is_definition)
4976 {
4977         const symbol_t *const    symbol  = entity->base.symbol;
4978         const namespace_tag_t    namespc = (namespace_tag_t)entity->base.namespc;
4979         const source_position_t *pos     = &entity->base.source_position;
4980
4981         /* can happen in error cases */
4982         if (symbol == NULL)
4983                 return entity;
4984
4985         entity_t *previous_entity = get_entity(symbol, namespc);
4986         /* pushing the same entity twice will break the stack structure */
4987         assert(previous_entity != entity);
4988
4989         if (entity->kind == ENTITY_FUNCTION) {
4990                 type_t *const orig_type = entity->declaration.type;
4991                 type_t *const type      = skip_typeref(orig_type);
4992
4993                 assert(is_type_function(type));
4994                 if (type->function.unspecified_parameters &&
4995                                 warning.strict_prototypes &&
4996                                 previous_entity == NULL) {
4997                         warningf(pos, "function declaration '%#T' is not a prototype",
4998                                          orig_type, symbol);
4999                 }
5000
5001                 if (warning.main && current_scope == file_scope
5002                                 && is_sym_main(symbol)) {
5003                         check_type_of_main(entity);
5004                 }
5005         }
5006
5007         if (is_declaration(entity) &&
5008                         warning.nested_externs &&
5009                         entity->declaration.storage_class == STORAGE_CLASS_EXTERN &&
5010                         current_scope != file_scope) {
5011                 warningf(pos, "nested extern declaration of '%#T'",
5012                          entity->declaration.type, symbol);
5013         }
5014
5015         if (previous_entity != NULL &&
5016                         previous_entity->base.parent_scope == &current_function->parameters &&
5017                         previous_entity->base.parent_scope->depth + 1 == current_scope->depth) {
5018                 assert(previous_entity->kind == ENTITY_PARAMETER);
5019                 errorf(pos,
5020                        "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
5021                                          entity->declaration.type, symbol,
5022                                          previous_entity->declaration.type, symbol,
5023                                          &previous_entity->base.source_position);
5024                 goto finish;
5025         }
5026
5027         if (previous_entity != NULL &&
5028                         previous_entity->base.parent_scope == current_scope) {
5029                 if (previous_entity->kind != entity->kind) {
5030                         error_redefined_as_different_kind(pos, previous_entity,
5031                                                           entity->kind);
5032                         goto finish;
5033                 }
5034                 if (previous_entity->kind == ENTITY_ENUM_VALUE) {
5035                         errorf(pos, "redeclaration of enum entry '%Y' (declared %P)",
5036                                    symbol, &previous_entity->base.source_position);
5037                         goto finish;
5038                 }
5039                 if (previous_entity->kind == ENTITY_TYPEDEF) {
5040                         /* TODO: C++ allows this for exactly the same type */
5041                         errorf(pos, "redefinition of typedef '%Y' (declared %P)",
5042                                symbol, &previous_entity->base.source_position);
5043                         goto finish;
5044                 }
5045
5046                 /* at this point we should have only VARIABLES or FUNCTIONS */
5047                 assert(is_declaration(previous_entity) && is_declaration(entity));
5048
5049                 declaration_t *const prev_decl = &previous_entity->declaration;
5050                 declaration_t *const decl      = &entity->declaration;
5051
5052                 /* can happen for K&R style declarations */
5053                 if (prev_decl->type       == NULL             &&
5054                                 previous_entity->kind == ENTITY_PARAMETER &&
5055                                 entity->kind          == ENTITY_PARAMETER) {
5056                         prev_decl->type                   = decl->type;
5057                         prev_decl->storage_class          = decl->storage_class;
5058                         prev_decl->declared_storage_class = decl->declared_storage_class;
5059                         prev_decl->modifiers              = decl->modifiers;
5060                         prev_decl->deprecated_string      = decl->deprecated_string;
5061                         return previous_entity;
5062                 }
5063
5064                 type_t *const orig_type = decl->type;
5065                 assert(orig_type != NULL);
5066                 type_t *const type      = skip_typeref(orig_type);
5067                 type_t *      prev_type = skip_typeref(prev_decl->type);
5068
5069                 if (!types_compatible(type, prev_type)) {
5070                         errorf(pos,
5071                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
5072                                    orig_type, symbol, prev_decl->type, symbol,
5073                                    &previous_entity->base.source_position);
5074                 } else {
5075                         unsigned old_storage_class = prev_decl->storage_class;
5076                         if (warning.redundant_decls               &&
5077                                         is_definition                     &&
5078                                         !prev_decl->used                  &&
5079                                         !(prev_decl->modifiers & DM_USED) &&
5080                                         prev_decl->storage_class == STORAGE_CLASS_STATIC) {
5081                                 warningf(&previous_entity->base.source_position,
5082                                          "unnecessary static forward declaration for '%#T'",
5083                                          prev_decl->type, symbol);
5084                         }
5085
5086                         unsigned new_storage_class = decl->storage_class;
5087                         if (is_type_incomplete(prev_type)) {
5088                                 prev_decl->type = type;
5089                                 prev_type       = type;
5090                         }
5091
5092                         /* pretend no storage class means extern for function
5093                          * declarations (except if the previous declaration is neither
5094                          * none nor extern) */
5095                         if (entity->kind == ENTITY_FUNCTION) {
5096                                 if (prev_type->function.unspecified_parameters) {
5097                                         prev_decl->type = type;
5098                                         prev_type       = type;
5099                                 }
5100
5101                                 switch (old_storage_class) {
5102                                 case STORAGE_CLASS_NONE:
5103                                         old_storage_class = STORAGE_CLASS_EXTERN;
5104                                         /* FALLTHROUGH */
5105
5106                                 case STORAGE_CLASS_EXTERN:
5107                                         if (is_definition) {
5108                                                 if (warning.missing_prototypes &&
5109                                                     prev_type->function.unspecified_parameters &&
5110                                                     !is_sym_main(symbol)) {
5111                                                         warningf(pos, "no previous prototype for '%#T'",
5112                                                                          orig_type, symbol);
5113                                                 }
5114                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
5115                                                 new_storage_class = STORAGE_CLASS_EXTERN;
5116                                         }
5117                                         break;
5118
5119                                 default:
5120                                         break;
5121                                 }
5122                         }
5123
5124                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
5125                                         new_storage_class == STORAGE_CLASS_EXTERN) {
5126 warn_redundant_declaration:
5127                                 if (!is_definition           &&
5128                                     warning.redundant_decls  &&
5129                                     is_type_valid(prev_type) &&
5130                                     strcmp(previous_entity->base.source_position.input_name,
5131                                            "<builtin>") != 0) {
5132                                         warningf(pos,
5133                                                  "redundant declaration for '%Y' (declared %P)",
5134                                                  symbol, &previous_entity->base.source_position);
5135                                 }
5136                         } else if (current_function == NULL) {
5137                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
5138                                     new_storage_class == STORAGE_CLASS_STATIC) {
5139                                         errorf(pos,
5140                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
5141                                                symbol, &previous_entity->base.source_position);
5142                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
5143                                         prev_decl->storage_class          = STORAGE_CLASS_NONE;
5144                                         prev_decl->declared_storage_class = STORAGE_CLASS_NONE;
5145                                 } else {
5146                                         /* ISO/IEC 14882:1998(E) §C.1.2:1 */
5147                                         if (c_mode & _CXX)
5148                                                 goto error_redeclaration;
5149                                         goto warn_redundant_declaration;
5150                                 }
5151                         } else if (is_type_valid(prev_type)) {
5152                                 if (old_storage_class == new_storage_class) {
5153 error_redeclaration:
5154                                         errorf(pos, "redeclaration of '%Y' (declared %P)",
5155                                                symbol, &previous_entity->base.source_position);
5156                                 } else {
5157                                         errorf(pos,
5158                                                "redeclaration of '%Y' with different linkage (declared %P)",
5159                                                symbol, &previous_entity->base.source_position);
5160                                 }
5161                         }
5162                 }
5163
5164                 prev_decl->modifiers |= decl->modifiers;
5165                 if (entity->kind == ENTITY_FUNCTION) {
5166                         previous_entity->function.is_inline |= entity->function.is_inline;
5167                 }
5168                 return previous_entity;
5169         }
5170
5171         if (entity->kind == ENTITY_FUNCTION) {
5172                 if (is_definition &&
5173                                 entity->declaration.storage_class != STORAGE_CLASS_STATIC) {
5174                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
5175                                 warningf(pos, "no previous prototype for '%#T'",
5176                                          entity->declaration.type, symbol);
5177                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
5178                                 warningf(pos, "no previous declaration for '%#T'",
5179                                          entity->declaration.type, symbol);
5180                         }
5181                 }
5182         } else if (warning.missing_declarations &&
5183                         entity->kind == ENTITY_VARIABLE &&
5184                         current_scope == file_scope) {
5185                 declaration_t *declaration = &entity->declaration;
5186                 if (declaration->storage_class == STORAGE_CLASS_NONE) {
5187                         warningf(pos, "no previous declaration for '%#T'",
5188                                  declaration->type, symbol);
5189                 }
5190         }
5191
5192 finish:
5193         assert(entity->base.parent_scope == NULL);
5194         assert(current_scope != NULL);
5195
5196         entity->base.parent_scope = current_scope;
5197         entity->base.namespc      = NAMESPACE_NORMAL;
5198         environment_push(entity);
5199         append_entity(current_scope, entity);
5200
5201         return entity;
5202 }
5203
5204 static void parser_error_multiple_definition(entity_t *entity,
5205                 const source_position_t *source_position)
5206 {
5207         errorf(source_position, "multiple definition of '%Y' (declared %P)",
5208                entity->base.symbol, &entity->base.source_position);
5209 }
5210
5211 static bool is_declaration_specifier(const token_t *token,
5212                                      bool only_specifiers_qualifiers)
5213 {
5214         switch (token->type) {
5215                 TYPE_SPECIFIERS
5216                 TYPE_QUALIFIERS
5217                         return true;
5218                 case T_IDENTIFIER:
5219                         return is_typedef_symbol(token->v.symbol);
5220
5221                 case T___extension__:
5222                 STORAGE_CLASSES
5223                         return !only_specifiers_qualifiers;
5224
5225                 default:
5226                         return false;
5227         }
5228 }
5229
5230 static void parse_init_declarator_rest(entity_t *entity)
5231 {
5232         assert(is_declaration(entity));
5233         declaration_t *const declaration = &entity->declaration;
5234
5235         eat('=');
5236
5237         type_t *orig_type = declaration->type;
5238         type_t *type      = skip_typeref(orig_type);
5239
5240         if (entity->kind == ENTITY_VARIABLE
5241                         && entity->variable.initializer != NULL) {
5242                 parser_error_multiple_definition(entity, HERE);
5243         }
5244
5245         bool must_be_constant = false;
5246         if (declaration->storage_class == STORAGE_CLASS_STATIC ||
5247             entity->base.parent_scope  == file_scope) {
5248                 must_be_constant = true;
5249         }
5250
5251         if (is_type_function(type)) {
5252                 errorf(&entity->base.source_position,
5253                        "function '%#T' is initialized like a variable",
5254                        orig_type, entity->base.symbol);
5255                 orig_type = type_error_type;
5256         }
5257
5258         parse_initializer_env_t env;
5259         env.type             = orig_type;
5260         env.must_be_constant = must_be_constant;
5261         env.entity           = entity;
5262         current_init_decl    = entity;
5263
5264         initializer_t *initializer = parse_initializer(&env);
5265         current_init_decl = NULL;
5266
5267         if (entity->kind == ENTITY_VARIABLE) {
5268                 /* § 6.7.5 (22)  array initializers for arrays with unknown size
5269                  * determine the array type size */
5270                 declaration->type            = env.type;
5271                 entity->variable.initializer = initializer;
5272         }
5273 }
5274
5275 /* parse rest of a declaration without any declarator */
5276 static void parse_anonymous_declaration_rest(
5277                 const declaration_specifiers_t *specifiers)
5278 {
5279         eat(';');
5280         anonymous_entity = NULL;
5281
5282         if (warning.other) {
5283                 if (specifiers->storage_class != STORAGE_CLASS_NONE ||
5284                                 specifiers->thread_local) {
5285                         warningf(&specifiers->source_position,
5286                                  "useless storage class in empty declaration");
5287                 }
5288
5289                 type_t *type = specifiers->type;
5290                 switch (type->kind) {
5291                         case TYPE_COMPOUND_STRUCT:
5292                         case TYPE_COMPOUND_UNION: {
5293                                 if (type->compound.compound->base.symbol == NULL) {
5294                                         warningf(&specifiers->source_position,
5295                                                  "unnamed struct/union that defines no instances");
5296                                 }
5297                                 break;
5298                         }
5299
5300                         case TYPE_ENUM:
5301                                 break;
5302
5303                         default:
5304                                 warningf(&specifiers->source_position, "empty declaration");
5305                                 break;
5306                 }
5307         }
5308 }
5309
5310 static void check_variable_type_complete(entity_t *ent)
5311 {
5312         if (ent->kind != ENTITY_VARIABLE)
5313                 return;
5314
5315         /* §6.7:7  If an identifier for an object is declared with no linkage, the
5316          *         type for the object shall be complete [...] */
5317         declaration_t *decl = &ent->declaration;
5318         if (decl->storage_class != STORAGE_CLASS_NONE)
5319                 return;
5320
5321         type_t *const orig_type = decl->type;
5322         type_t *const type      = skip_typeref(orig_type);
5323         if (!is_type_incomplete(type))
5324                 return;
5325
5326         /* GCC allows global arrays without size and assigns them a length of one,
5327          * if no different declaration follows */
5328         if (is_type_array(type) &&
5329                         c_mode & _GNUC      &&
5330                         ent->base.parent_scope == file_scope) {
5331                 ARR_APP1(declaration_t*, incomplete_arrays, decl);
5332                 return;
5333         }
5334
5335         errorf(&ent->base.source_position, "variable '%#T' has incomplete type",
5336                         orig_type, ent->base.symbol);
5337 }
5338
5339
5340 static void parse_declaration_rest(entity_t *ndeclaration,
5341                 const declaration_specifiers_t *specifiers,
5342                 parsed_declaration_func         finished_declaration,
5343                 declarator_flags_t              flags)
5344 {
5345         add_anchor_token(';');
5346         add_anchor_token(',');
5347         while (true) {
5348                 entity_t *entity = finished_declaration(ndeclaration, token.type == '=');
5349
5350                 if (token.type == '=') {
5351                         parse_init_declarator_rest(entity);
5352                 } else if (entity->kind == ENTITY_VARIABLE) {
5353                         /* ISO/IEC 14882:1998(E) §8.5.3:3  The initializer can be omitted
5354                          * [...] where the extern specifier is explicitly used. */
5355                         declaration_t *decl = &entity->declaration;
5356                         if (decl->storage_class != STORAGE_CLASS_EXTERN) {
5357                                 type_t *type = decl->type;
5358                                 if (is_type_reference(skip_typeref(type))) {
5359                                         errorf(&entity->base.source_position,
5360                                                         "reference '%#T' must be initialized",
5361                                                         type, entity->base.symbol);
5362                                 }
5363                         }
5364                 }
5365
5366                 check_variable_type_complete(entity);
5367
5368                 if (token.type != ',')
5369                         break;
5370                 eat(',');
5371
5372                 add_anchor_token('=');
5373                 ndeclaration = parse_declarator(specifiers, flags);
5374                 rem_anchor_token('=');
5375         }
5376         expect(';', end_error);
5377
5378 end_error:
5379         anonymous_entity = NULL;
5380         rem_anchor_token(';');
5381         rem_anchor_token(',');
5382 }
5383
5384 static entity_t *finished_kr_declaration(entity_t *entity, bool is_definition)
5385 {
5386         symbol_t *symbol = entity->base.symbol;
5387         if (symbol == NULL) {
5388                 errorf(HERE, "anonymous declaration not valid as function parameter");
5389                 return entity;
5390         }
5391
5392         assert(entity->base.namespc == NAMESPACE_NORMAL);
5393         entity_t *previous_entity = get_entity(symbol, NAMESPACE_NORMAL);
5394         if (previous_entity == NULL
5395                         || previous_entity->base.parent_scope != current_scope) {
5396                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
5397                        symbol);
5398                 return entity;
5399         }
5400
5401         if (is_definition) {
5402                 errorf(HERE, "parameter '%Y' is initialised", entity->base.symbol);
5403         }
5404
5405         return record_entity(entity, false);
5406 }
5407
5408 static void parse_declaration(parsed_declaration_func finished_declaration,
5409                               declarator_flags_t      flags)
5410 {
5411         declaration_specifiers_t specifiers;
5412         memset(&specifiers, 0, sizeof(specifiers));
5413
5414         add_anchor_token(';');
5415         parse_declaration_specifiers(&specifiers);
5416         rem_anchor_token(';');
5417
5418         if (token.type == ';') {
5419                 parse_anonymous_declaration_rest(&specifiers);
5420         } else {
5421                 entity_t *entity = parse_declarator(&specifiers, flags);
5422                 parse_declaration_rest(entity, &specifiers, finished_declaration, flags);
5423         }
5424 }
5425
5426 static type_t *get_default_promoted_type(type_t *orig_type)
5427 {
5428         type_t *result = orig_type;
5429
5430         type_t *type = skip_typeref(orig_type);
5431         if (is_type_integer(type)) {
5432                 result = promote_integer(type);
5433         } else if (type == type_float) {
5434                 result = type_double;
5435         }
5436
5437         return result;
5438 }
5439
5440 static void parse_kr_declaration_list(entity_t *entity)
5441 {
5442         if (entity->kind != ENTITY_FUNCTION)
5443                 return;
5444
5445         type_t *type = skip_typeref(entity->declaration.type);
5446         assert(is_type_function(type));
5447         if (!type->function.kr_style_parameters)
5448                 return;
5449
5450
5451         add_anchor_token('{');
5452
5453         /* push function parameters */
5454         size_t const  top       = environment_top();
5455         scope_t      *old_scope = scope_push(&entity->function.parameters);
5456
5457         entity_t *parameter = entity->function.parameters.entities;
5458         for ( ; parameter != NULL; parameter = parameter->base.next) {
5459                 assert(parameter->base.parent_scope == NULL);
5460                 parameter->base.parent_scope = current_scope;
5461                 environment_push(parameter);
5462         }
5463
5464         /* parse declaration list */
5465         for (;;) {
5466                 switch (token.type) {
5467                         DECLARATION_START
5468                         case T___extension__:
5469                         /* This covers symbols, which are no type, too, and results in
5470                          * better error messages.  The typical cases are misspelled type
5471                          * names and missing includes. */
5472                         case T_IDENTIFIER:
5473                                 parse_declaration(finished_kr_declaration, DECL_IS_PARAMETER);
5474                                 break;
5475                         default:
5476                                 goto decl_list_end;
5477                 }
5478         }
5479 decl_list_end:
5480
5481         /* pop function parameters */
5482         assert(current_scope == &entity->function.parameters);
5483         scope_pop(old_scope);
5484         environment_pop_to(top);
5485
5486         /* update function type */
5487         type_t *new_type = duplicate_type(type);
5488
5489         function_parameter_t *parameters     = NULL;
5490         function_parameter_t *last_parameter = NULL;
5491
5492         parameter = entity->function.parameters.entities;
5493         for (; parameter != NULL; parameter = parameter->base.next) {
5494                 type_t *parameter_type = parameter->declaration.type;
5495                 if (parameter_type == NULL) {
5496                         if (strict_mode) {
5497                                 errorf(HERE, "no type specified for function parameter '%Y'",
5498                                        parameter->base.symbol);
5499                         } else {
5500                                 if (warning.implicit_int) {
5501                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
5502                                                  parameter->base.symbol);
5503                                 }
5504                                 parameter_type              = type_int;
5505                                 parameter->declaration.type = parameter_type;
5506                         }
5507                 }
5508
5509                 semantic_parameter_incomplete(parameter);
5510                 parameter_type = parameter->declaration.type;
5511
5512                 /*
5513                  * we need the default promoted types for the function type
5514                  */
5515                 parameter_type = get_default_promoted_type(parameter_type);
5516
5517                 function_parameter_t *function_parameter
5518                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
5519                 memset(function_parameter, 0, sizeof(function_parameter[0]));
5520
5521                 function_parameter->type = parameter_type;
5522                 if (last_parameter != NULL) {
5523                         last_parameter->next = function_parameter;
5524                 } else {
5525                         parameters = function_parameter;
5526                 }
5527                 last_parameter = function_parameter;
5528         }
5529
5530         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
5531          * prototype */
5532         new_type->function.parameters             = parameters;
5533         new_type->function.unspecified_parameters = true;
5534
5535         type = typehash_insert(new_type);
5536         if (type != new_type) {
5537                 obstack_free(type_obst, new_type);
5538         }
5539
5540         entity->declaration.type = type;
5541
5542         rem_anchor_token('{');
5543 }
5544
5545 static bool first_err = true;
5546
5547 /**
5548  * When called with first_err set, prints the name of the current function,
5549  * else does noting.
5550  */
5551 static void print_in_function(void)
5552 {
5553         if (first_err) {
5554                 first_err = false;
5555                 diagnosticf("%s: In function '%Y':\n",
5556                             current_function->base.base.source_position.input_name,
5557                             current_function->base.base.symbol);
5558         }
5559 }
5560
5561 /**
5562  * Check if all labels are defined in the current function.
5563  * Check if all labels are used in the current function.
5564  */
5565 static void check_labels(void)
5566 {
5567         for (const goto_statement_t *goto_statement = goto_first;
5568             goto_statement != NULL;
5569             goto_statement = goto_statement->next) {
5570                 /* skip computed gotos */
5571                 if (goto_statement->expression != NULL)
5572                         continue;
5573
5574                 label_t *label = goto_statement->label;
5575
5576                 label->used = true;
5577                 if (label->base.source_position.input_name == NULL) {
5578                         print_in_function();
5579                         errorf(&goto_statement->base.source_position,
5580                                "label '%Y' used but not defined", label->base.symbol);
5581                  }
5582         }
5583
5584         if (warning.unused_label) {
5585                 for (const label_statement_t *label_statement = label_first;
5586                          label_statement != NULL;
5587                          label_statement = label_statement->next) {
5588                         label_t *label = label_statement->label;
5589
5590                         if (! label->used) {
5591                                 print_in_function();
5592                                 warningf(&label_statement->base.source_position,
5593                                          "label '%Y' defined but not used", label->base.symbol);
5594                         }
5595                 }
5596         }
5597 }
5598
5599 static void warn_unused_entity(entity_t *entity, entity_t *last)
5600 {
5601         entity_t const *const end = last != NULL ? last->base.next : NULL;
5602         for (; entity != end; entity = entity->base.next) {
5603                 if (!is_declaration(entity))
5604                         continue;
5605
5606                 declaration_t *declaration = &entity->declaration;
5607                 if (declaration->implicit)
5608                         continue;
5609
5610                 if (!declaration->used) {
5611                         print_in_function();
5612                         const char *what = get_entity_kind_name(entity->kind);
5613                         warningf(&entity->base.source_position, "%s '%Y' is unused",
5614                                  what, entity->base.symbol);
5615                 } else if (entity->kind == ENTITY_VARIABLE && !entity->variable.read) {
5616                         print_in_function();
5617                         const char *what = get_entity_kind_name(entity->kind);
5618                         warningf(&entity->base.source_position, "%s '%Y' is never read",
5619                                  what, entity->base.symbol);
5620                 }
5621         }
5622 }
5623
5624 static void check_unused_variables(statement_t *const stmt, void *const env)
5625 {
5626         (void)env;
5627
5628         switch (stmt->kind) {
5629                 case STATEMENT_DECLARATION: {
5630                         declaration_statement_t const *const decls = &stmt->declaration;
5631                         warn_unused_entity(decls->declarations_begin,
5632                                            decls->declarations_end);
5633                         return;
5634                 }
5635
5636                 case STATEMENT_FOR:
5637                         warn_unused_entity(stmt->fors.scope.entities, NULL);
5638                         return;
5639
5640                 default:
5641                         return;
5642         }
5643 }
5644
5645 /**
5646  * Check declarations of current_function for unused entities.
5647  */
5648 static void check_declarations(void)
5649 {
5650         if (warning.unused_parameter) {
5651                 const scope_t *scope = &current_function->parameters;
5652
5653                 /* do not issue unused warnings for main */
5654                 if (!is_sym_main(current_function->base.base.symbol)) {
5655                         warn_unused_entity(scope->entities, NULL);
5656                 }
5657         }
5658         if (warning.unused_variable) {
5659                 walk_statements(current_function->statement, check_unused_variables,
5660                                 NULL);
5661         }
5662 }
5663
5664 static int determine_truth(expression_t const* const cond)
5665 {
5666         return
5667                 !is_constant_expression(cond) ? 0 :
5668                 fold_constant(cond) != 0      ? 1 :
5669                 -1;
5670 }
5671
5672 static void check_reachable(statement_t *);
5673 static bool reaches_end;
5674
5675 static bool expression_returns(expression_t const *const expr)
5676 {
5677         switch (expr->kind) {
5678                 case EXPR_CALL: {
5679                         expression_t const *const func = expr->call.function;
5680                         if (func->kind == EXPR_REFERENCE) {
5681                                 entity_t *entity = func->reference.entity;
5682                                 if (entity->kind == ENTITY_FUNCTION
5683                                                 && entity->declaration.modifiers & DM_NORETURN)
5684                                         return false;
5685                         }
5686
5687                         if (!expression_returns(func))
5688                                 return false;
5689
5690                         for (call_argument_t const* arg = expr->call.arguments; arg != NULL; arg = arg->next) {
5691                                 if (!expression_returns(arg->expression))
5692                                         return false;
5693                         }
5694
5695                         return true;
5696                 }
5697
5698                 case EXPR_REFERENCE:
5699                 case EXPR_REFERENCE_ENUM_VALUE:
5700                 case EXPR_CONST:
5701                 case EXPR_CHARACTER_CONSTANT:
5702                 case EXPR_WIDE_CHARACTER_CONSTANT:
5703                 case EXPR_STRING_LITERAL:
5704                 case EXPR_WIDE_STRING_LITERAL:
5705                 case EXPR_COMPOUND_LITERAL: // TODO descend into initialisers
5706                 case EXPR_LABEL_ADDRESS:
5707                 case EXPR_CLASSIFY_TYPE:
5708                 case EXPR_SIZEOF: // TODO handle obscure VLA case
5709                 case EXPR_ALIGNOF:
5710                 case EXPR_FUNCNAME:
5711                 case EXPR_BUILTIN_SYMBOL:
5712                 case EXPR_BUILTIN_CONSTANT_P:
5713                 case EXPR_BUILTIN_PREFETCH:
5714                 case EXPR_OFFSETOF:
5715                 case EXPR_INVALID:
5716                         return true;
5717
5718                 case EXPR_STATEMENT: {
5719                         bool old_reaches_end = reaches_end;
5720                         reaches_end = false;
5721                         check_reachable(expr->statement.statement);
5722                         bool returns = reaches_end;
5723                         reaches_end = old_reaches_end;
5724                         return returns;
5725                 }
5726
5727                 case EXPR_CONDITIONAL:
5728                         // TODO handle constant expression
5729
5730                         if (!expression_returns(expr->conditional.condition))
5731                                 return false;
5732
5733                         if (expr->conditional.true_expression != NULL
5734                                         && expression_returns(expr->conditional.true_expression))
5735                                 return true;
5736
5737                         return expression_returns(expr->conditional.false_expression);
5738
5739                 case EXPR_SELECT:
5740                         return expression_returns(expr->select.compound);
5741
5742                 case EXPR_ARRAY_ACCESS:
5743                         return
5744                                 expression_returns(expr->array_access.array_ref) &&
5745                                 expression_returns(expr->array_access.index);
5746
5747                 case EXPR_VA_START:
5748                         return expression_returns(expr->va_starte.ap);
5749
5750                 case EXPR_VA_ARG:
5751                         return expression_returns(expr->va_arge.ap);
5752
5753                 EXPR_UNARY_CASES_MANDATORY
5754                         return expression_returns(expr->unary.value);
5755
5756                 case EXPR_UNARY_THROW:
5757                         return false;
5758
5759                 EXPR_BINARY_CASES
5760                         // TODO handle constant lhs of && and ||
5761                         return
5762                                 expression_returns(expr->binary.left) &&
5763                                 expression_returns(expr->binary.right);
5764
5765                 case EXPR_UNKNOWN:
5766                         break;
5767         }
5768
5769         panic("unhandled expression");
5770 }
5771
5772 static bool initializer_returns(initializer_t const *const init)
5773 {
5774         switch (init->kind) {
5775                 case INITIALIZER_VALUE:
5776                         return expression_returns(init->value.value);
5777
5778                 case INITIALIZER_LIST: {
5779                         initializer_t * const*       i       = init->list.initializers;
5780                         initializer_t * const* const end     = i + init->list.len;
5781                         bool                         returns = true;
5782                         for (; i != end; ++i) {
5783                                 if (!initializer_returns(*i))
5784                                         returns = false;
5785                         }
5786                         return returns;
5787                 }
5788
5789                 case INITIALIZER_STRING:
5790                 case INITIALIZER_WIDE_STRING:
5791                 case INITIALIZER_DESIGNATOR: // designators have no payload
5792                         return true;
5793         }
5794         panic("unhandled initializer");
5795 }
5796
5797 static bool noreturn_candidate;
5798
5799 static void check_reachable(statement_t *const stmt)
5800 {
5801         if (stmt->base.reachable)
5802                 return;
5803         if (stmt->kind != STATEMENT_DO_WHILE)
5804                 stmt->base.reachable = true;
5805
5806         statement_t *last = stmt;
5807         statement_t *next;
5808         switch (stmt->kind) {
5809                 case STATEMENT_INVALID:
5810                 case STATEMENT_EMPTY:
5811                 case STATEMENT_ASM:
5812                         next = stmt->base.next;
5813                         break;
5814
5815                 case STATEMENT_DECLARATION: {
5816                         declaration_statement_t const *const decl = &stmt->declaration;
5817                         entity_t                const *      ent  = decl->declarations_begin;
5818                         entity_t                const *const last = decl->declarations_end;
5819                         if (ent != NULL) {
5820                                 for (;; ent = ent->base.next) {
5821                                         if (ent->kind                 == ENTITY_VARIABLE &&
5822                                                         ent->variable.initializer != NULL            &&
5823                                                         !initializer_returns(ent->variable.initializer)) {
5824                                                 return;
5825                                         }
5826                                         if (ent == last)
5827                                                 break;
5828                                 }
5829                         }
5830                         next = stmt->base.next;
5831                         break;
5832                 }
5833
5834                 case STATEMENT_COMPOUND:
5835                         next = stmt->compound.statements;
5836                         if (next == NULL)
5837                                 next = stmt->base.next;
5838                         break;
5839
5840                 case STATEMENT_RETURN: {
5841                         expression_t const *const val = stmt->returns.value;
5842                         if (val == NULL || expression_returns(val))
5843                                 noreturn_candidate = false;
5844                         return;
5845                 }
5846
5847                 case STATEMENT_IF: {
5848                         if_statement_t const *const ifs  = &stmt->ifs;
5849                         expression_t   const *const cond = ifs->condition;
5850
5851                         if (!expression_returns(cond))
5852                                 return;
5853
5854                         int const val = determine_truth(cond);
5855
5856                         if (val >= 0)
5857                                 check_reachable(ifs->true_statement);
5858
5859                         if (val > 0)
5860                                 return;
5861
5862                         if (ifs->false_statement != NULL) {
5863                                 check_reachable(ifs->false_statement);
5864                                 return;
5865                         }
5866
5867                         next = stmt->base.next;
5868                         break;
5869                 }
5870
5871                 case STATEMENT_SWITCH: {
5872                         switch_statement_t const *const switchs = &stmt->switchs;
5873                         expression_t       const *const expr    = switchs->expression;
5874
5875                         if (!expression_returns(expr))
5876                                 return;
5877
5878                         if (is_constant_expression(expr)) {
5879                                 long                    const val      = fold_constant(expr);
5880                                 case_label_statement_t *      defaults = NULL;
5881                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5882                                         if (i->expression == NULL) {
5883                                                 defaults = i;
5884                                                 continue;
5885                                         }
5886
5887                                         if (i->first_case <= val && val <= i->last_case) {
5888                                                 check_reachable((statement_t*)i);
5889                                                 return;
5890                                         }
5891                                 }
5892
5893                                 if (defaults != NULL) {
5894                                         check_reachable((statement_t*)defaults);
5895                                         return;
5896                                 }
5897                         } else {
5898                                 bool has_default = false;
5899                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5900                                         if (i->expression == NULL)
5901                                                 has_default = true;
5902
5903                                         check_reachable((statement_t*)i);
5904                                 }
5905
5906                                 if (has_default)
5907                                         return;
5908                         }
5909
5910                         next = stmt->base.next;
5911                         break;
5912                 }
5913
5914                 case STATEMENT_EXPRESSION: {
5915                         /* Check for noreturn function call */
5916                         expression_t const *const expr = stmt->expression.expression;
5917                         if (!expression_returns(expr))
5918                                 return;
5919
5920                         next = stmt->base.next;
5921                         break;
5922                 }
5923
5924                 case STATEMENT_CONTINUE: {
5925                         statement_t *parent = stmt;
5926                         for (;;) {
5927                                 parent = parent->base.parent;
5928                                 if (parent == NULL) /* continue not within loop */
5929                                         return;
5930
5931                                 next = parent;
5932                                 switch (parent->kind) {
5933                                         case STATEMENT_WHILE:    goto continue_while;
5934                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5935                                         case STATEMENT_FOR:      goto continue_for;
5936
5937                                         default: break;
5938                                 }
5939                         }
5940                 }
5941
5942                 case STATEMENT_BREAK: {
5943                         statement_t *parent = stmt;
5944                         for (;;) {
5945                                 parent = parent->base.parent;
5946                                 if (parent == NULL) /* break not within loop/switch */
5947                                         return;
5948
5949                                 switch (parent->kind) {
5950                                         case STATEMENT_SWITCH:
5951                                         case STATEMENT_WHILE:
5952                                         case STATEMENT_DO_WHILE:
5953                                         case STATEMENT_FOR:
5954                                                 last = parent;
5955                                                 next = parent->base.next;
5956                                                 goto found_break_parent;
5957
5958                                         default: break;
5959                                 }
5960                         }
5961 found_break_parent:
5962                         break;
5963                 }
5964
5965                 case STATEMENT_GOTO:
5966                         if (stmt->gotos.expression) {
5967                                 if (!expression_returns(stmt->gotos.expression))
5968                                         return;
5969
5970                                 statement_t *parent = stmt->base.parent;
5971                                 if (parent == NULL) /* top level goto */
5972                                         return;
5973                                 next = parent;
5974                         } else {
5975                                 next = stmt->gotos.label->statement;
5976                                 if (next == NULL) /* missing label */
5977                                         return;
5978                         }
5979                         break;
5980
5981                 case STATEMENT_LABEL:
5982                         next = stmt->label.statement;
5983                         break;
5984
5985                 case STATEMENT_CASE_LABEL:
5986                         next = stmt->case_label.statement;
5987                         break;
5988
5989                 case STATEMENT_WHILE: {
5990                         while_statement_t const *const whiles = &stmt->whiles;
5991                         expression_t      const *const cond   = whiles->condition;
5992
5993                         if (!expression_returns(cond))
5994                                 return;
5995
5996                         int const val = determine_truth(cond);
5997
5998                         if (val >= 0)
5999                                 check_reachable(whiles->body);
6000
6001                         if (val > 0)
6002                                 return;
6003
6004                         next = stmt->base.next;
6005                         break;
6006                 }
6007
6008                 case STATEMENT_DO_WHILE:
6009                         next = stmt->do_while.body;
6010                         break;
6011
6012                 case STATEMENT_FOR: {
6013                         for_statement_t *const fors = &stmt->fors;
6014
6015                         if (fors->condition_reachable)
6016                                 return;
6017                         fors->condition_reachable = true;
6018
6019                         expression_t const *const cond = fors->condition;
6020
6021                         int val;
6022                         if (cond == NULL) {
6023                                 val = 1;
6024                         } else if (expression_returns(cond)) {
6025                                 val = determine_truth(cond);
6026                         } else {
6027                                 return;
6028                         }
6029
6030                         if (val >= 0)
6031                                 check_reachable(fors->body);
6032
6033                         if (val > 0)
6034                                 return;
6035
6036                         next = stmt->base.next;
6037                         break;
6038                 }
6039
6040                 case STATEMENT_MS_TRY: {
6041                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
6042                         check_reachable(ms_try->try_statement);
6043                         next = ms_try->final_statement;
6044                         break;
6045                 }
6046
6047                 case STATEMENT_LEAVE: {
6048                         statement_t *parent = stmt;
6049                         for (;;) {
6050                                 parent = parent->base.parent;
6051                                 if (parent == NULL) /* __leave not within __try */
6052                                         return;
6053
6054                                 if (parent->kind == STATEMENT_MS_TRY) {
6055                                         last = parent;
6056                                         next = parent->ms_try.final_statement;
6057                                         break;
6058                                 }
6059                         }
6060                         break;
6061                 }
6062
6063                 default:
6064                         panic("invalid statement kind");
6065         }
6066
6067         while (next == NULL) {
6068                 next = last->base.parent;
6069                 if (next == NULL) {
6070                         noreturn_candidate = false;
6071
6072                         type_t *const type = current_function->base.type;
6073                         assert(is_type_function(type));
6074                         type_t *const ret  = skip_typeref(type->function.return_type);
6075                         if (warning.return_type                    &&
6076                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
6077                             is_type_valid(ret)                     &&
6078                             !is_sym_main(current_function->base.base.symbol)) {
6079                                 warningf(&stmt->base.source_position,
6080                                          "control reaches end of non-void function");
6081                         }
6082                         return;
6083                 }
6084
6085                 switch (next->kind) {
6086                         case STATEMENT_INVALID:
6087                         case STATEMENT_EMPTY:
6088                         case STATEMENT_DECLARATION:
6089                         case STATEMENT_EXPRESSION:
6090                         case STATEMENT_ASM:
6091                         case STATEMENT_RETURN:
6092                         case STATEMENT_CONTINUE:
6093                         case STATEMENT_BREAK:
6094                         case STATEMENT_GOTO:
6095                         case STATEMENT_LEAVE:
6096                                 panic("invalid control flow in function");
6097
6098                         case STATEMENT_COMPOUND:
6099                                 if (next->compound.stmt_expr) {
6100                                         reaches_end = true;
6101                                         return;
6102                                 }
6103                                 /* FALLTHROUGH */
6104                         case STATEMENT_IF:
6105                         case STATEMENT_SWITCH:
6106                         case STATEMENT_LABEL:
6107                         case STATEMENT_CASE_LABEL:
6108                                 last = next;
6109                                 next = next->base.next;
6110                                 break;
6111
6112                         case STATEMENT_WHILE: {
6113 continue_while:
6114                                 if (next->base.reachable)
6115                                         return;
6116                                 next->base.reachable = true;
6117
6118                                 while_statement_t const *const whiles = &next->whiles;
6119                                 expression_t      const *const cond   = whiles->condition;
6120
6121                                 if (!expression_returns(cond))
6122                                         return;
6123
6124                                 int const val = determine_truth(cond);
6125
6126                                 if (val >= 0)
6127                                         check_reachable(whiles->body);
6128
6129                                 if (val > 0)
6130                                         return;
6131
6132                                 last = next;
6133                                 next = next->base.next;
6134                                 break;
6135                         }
6136
6137                         case STATEMENT_DO_WHILE: {
6138 continue_do_while:
6139                                 if (next->base.reachable)
6140                                         return;
6141                                 next->base.reachable = true;
6142
6143                                 do_while_statement_t const *const dw   = &next->do_while;
6144                                 expression_t         const *const cond = dw->condition;
6145
6146                                 if (!expression_returns(cond))
6147                                         return;
6148
6149                                 int const val = determine_truth(cond);
6150
6151                                 if (val >= 0)
6152                                         check_reachable(dw->body);
6153
6154                                 if (val > 0)
6155                                         return;
6156
6157                                 last = next;
6158                                 next = next->base.next;
6159                                 break;
6160                         }
6161
6162                         case STATEMENT_FOR: {
6163 continue_for:;
6164                                 for_statement_t *const fors = &next->fors;
6165
6166                                 fors->step_reachable = true;
6167
6168                                 if (fors->condition_reachable)
6169                                         return;
6170                                 fors->condition_reachable = true;
6171
6172                                 expression_t const *const cond = fors->condition;
6173
6174                                 int val;
6175                                 if (cond == NULL) {
6176                                         val = 1;
6177                                 } else if (expression_returns(cond)) {
6178                                         val = determine_truth(cond);
6179                                 } else {
6180                                         return;
6181                                 }
6182
6183                                 if (val >= 0)
6184                                         check_reachable(fors->body);
6185
6186                                 if (val > 0)
6187                                         return;
6188
6189                                 last = next;
6190                                 next = next->base.next;
6191                                 break;
6192                         }
6193
6194                         case STATEMENT_MS_TRY:
6195                                 last = next;
6196                                 next = next->ms_try.final_statement;
6197                                 break;
6198                 }
6199         }
6200
6201         check_reachable(next);
6202 }
6203
6204 static void check_unreachable(statement_t* const stmt, void *const env)
6205 {
6206         (void)env;
6207
6208         switch (stmt->kind) {
6209                 case STATEMENT_DO_WHILE:
6210                         if (!stmt->base.reachable) {
6211                                 expression_t const *const cond = stmt->do_while.condition;
6212                                 if (determine_truth(cond) >= 0) {
6213                                         warningf(&cond->base.source_position,
6214                                                  "condition of do-while-loop is unreachable");
6215                                 }
6216                         }
6217                         return;
6218
6219                 case STATEMENT_FOR: {
6220                         for_statement_t const* const fors = &stmt->fors;
6221
6222                         // if init and step are unreachable, cond is unreachable, too
6223                         if (!stmt->base.reachable && !fors->step_reachable) {
6224                                 warningf(&stmt->base.source_position, "statement is unreachable");
6225                         } else {
6226                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
6227                                         warningf(&fors->initialisation->base.source_position,
6228                                                  "initialisation of for-statement is unreachable");
6229                                 }
6230
6231                                 if (!fors->condition_reachable && fors->condition != NULL) {
6232                                         warningf(&fors->condition->base.source_position,
6233                                                  "condition of for-statement is unreachable");
6234                                 }
6235
6236                                 if (!fors->step_reachable && fors->step != NULL) {
6237                                         warningf(&fors->step->base.source_position,
6238                                                  "step of for-statement is unreachable");
6239                                 }
6240                         }
6241                         return;
6242                 }
6243
6244                 case STATEMENT_COMPOUND:
6245                         if (stmt->compound.statements != NULL)
6246                                 return;
6247                         goto warn_unreachable;
6248
6249                 case STATEMENT_DECLARATION: {
6250                         /* Only warn if there is at least one declarator with an initializer.
6251                          * This typically occurs in switch statements. */
6252                         declaration_statement_t const *const decl = &stmt->declaration;
6253                         entity_t                const *      ent  = decl->declarations_begin;
6254                         entity_t                const *const last = decl->declarations_end;
6255                         if (ent != NULL) {
6256                                 for (;; ent = ent->base.next) {
6257                                         if (ent->kind                 == ENTITY_VARIABLE &&
6258                                                         ent->variable.initializer != NULL) {
6259                                                 goto warn_unreachable;
6260                                         }
6261                                         if (ent == last)
6262                                                 return;
6263                                 }
6264                         }
6265                 }
6266
6267                 default:
6268 warn_unreachable:
6269                         if (!stmt->base.reachable)
6270                                 warningf(&stmt->base.source_position, "statement is unreachable");
6271                         return;
6272         }
6273 }
6274
6275 static void parse_external_declaration(void)
6276 {
6277         /* function-definitions and declarations both start with declaration
6278          * specifiers */
6279         declaration_specifiers_t specifiers;
6280         memset(&specifiers, 0, sizeof(specifiers));
6281
6282         add_anchor_token(';');
6283         parse_declaration_specifiers(&specifiers);
6284         rem_anchor_token(';');
6285
6286         /* must be a declaration */
6287         if (token.type == ';') {
6288                 parse_anonymous_declaration_rest(&specifiers);
6289                 return;
6290         }
6291
6292         add_anchor_token(',');
6293         add_anchor_token('=');
6294         add_anchor_token(';');
6295         add_anchor_token('{');
6296
6297         /* declarator is common to both function-definitions and declarations */
6298         entity_t *ndeclaration = parse_declarator(&specifiers, DECL_FLAGS_NONE);
6299
6300         rem_anchor_token('{');
6301         rem_anchor_token(';');
6302         rem_anchor_token('=');
6303         rem_anchor_token(',');
6304
6305         /* must be a declaration */
6306         switch (token.type) {
6307                 case ',':
6308                 case ';':
6309                 case '=':
6310                         parse_declaration_rest(ndeclaration, &specifiers, record_entity,
6311                                         DECL_FLAGS_NONE);
6312                         return;
6313         }
6314
6315         /* must be a function definition */
6316         parse_kr_declaration_list(ndeclaration);
6317
6318         if (token.type != '{') {
6319                 parse_error_expected("while parsing function definition", '{', NULL);
6320                 eat_until_matching_token(';');
6321                 return;
6322         }
6323
6324         assert(is_declaration(ndeclaration));
6325         type_t *type = skip_typeref(ndeclaration->declaration.type);
6326
6327         if (!is_type_function(type)) {
6328                 if (is_type_valid(type)) {
6329                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
6330                                type, ndeclaration->base.symbol);
6331                 }
6332                 eat_block();
6333                 return;
6334         }
6335
6336         if (warning.aggregate_return &&
6337             is_type_compound(skip_typeref(type->function.return_type))) {
6338                 warningf(HERE, "function '%Y' returns an aggregate",
6339                          ndeclaration->base.symbol);
6340         }
6341         if (warning.traditional && !type->function.unspecified_parameters) {
6342                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
6343                         ndeclaration->base.symbol);
6344         }
6345         if (warning.old_style_definition && type->function.unspecified_parameters) {
6346                 warningf(HERE, "old-style function definition '%Y'",
6347                         ndeclaration->base.symbol);
6348         }
6349
6350         /* § 6.7.5.3 (14) a function definition with () means no
6351          * parameters (and not unspecified parameters) */
6352         if (type->function.unspecified_parameters
6353                         && type->function.parameters == NULL
6354                         && !type->function.kr_style_parameters) {
6355                 type_t *duplicate = duplicate_type(type);
6356                 duplicate->function.unspecified_parameters = false;
6357
6358                 type = typehash_insert(duplicate);
6359                 if (type != duplicate) {
6360                         obstack_free(type_obst, duplicate);
6361                 }
6362                 ndeclaration->declaration.type = type;
6363         }
6364
6365         entity_t *const entity = record_entity(ndeclaration, true);
6366         assert(entity->kind == ENTITY_FUNCTION);
6367         assert(ndeclaration->kind == ENTITY_FUNCTION);
6368
6369         function_t *function = &entity->function;
6370         if (ndeclaration != entity) {
6371                 function->parameters = ndeclaration->function.parameters;
6372         }
6373         assert(is_declaration(entity));
6374         type = skip_typeref(entity->declaration.type);
6375
6376         /* push function parameters and switch scope */
6377         size_t const  top       = environment_top();
6378         scope_t      *old_scope = scope_push(&function->parameters);
6379
6380         entity_t *parameter = function->parameters.entities;
6381         for (; parameter != NULL; parameter = parameter->base.next) {
6382                 if (parameter->base.parent_scope == &ndeclaration->function.parameters) {
6383                         parameter->base.parent_scope = current_scope;
6384                 }
6385                 assert(parameter->base.parent_scope == NULL
6386                                 || parameter->base.parent_scope == current_scope);
6387                 parameter->base.parent_scope = current_scope;
6388                 if (parameter->base.symbol == NULL) {
6389                         errorf(&parameter->base.source_position, "parameter name omitted");
6390                         continue;
6391                 }
6392                 environment_push(parameter);
6393         }
6394
6395         if (function->statement != NULL) {
6396                 parser_error_multiple_definition(entity, HERE);
6397                 eat_block();
6398         } else {
6399                 /* parse function body */
6400                 int         label_stack_top      = label_top();
6401                 function_t *old_current_function = current_function;
6402                 current_function                 = function;
6403                 current_parent                   = NULL;
6404
6405                 goto_first   = NULL;
6406                 goto_anchor  = &goto_first;
6407                 label_first  = NULL;
6408                 label_anchor = &label_first;
6409
6410                 statement_t *const body = parse_compound_statement(false);
6411                 function->statement = body;
6412                 first_err = true;
6413                 check_labels();
6414                 check_declarations();
6415                 if (warning.return_type      ||
6416                     warning.unreachable_code ||
6417                     (warning.missing_noreturn
6418                      && !(function->base.modifiers & DM_NORETURN))) {
6419                         noreturn_candidate = true;
6420                         check_reachable(body);
6421                         if (warning.unreachable_code)
6422                                 walk_statements(body, check_unreachable, NULL);
6423                         if (warning.missing_noreturn &&
6424                             noreturn_candidate       &&
6425                             !(function->base.modifiers & DM_NORETURN)) {
6426                                 warningf(&body->base.source_position,
6427                                          "function '%#T' is candidate for attribute 'noreturn'",
6428                                          type, entity->base.symbol);
6429                         }
6430                 }
6431
6432                 assert(current_parent   == NULL);
6433                 assert(current_function == function);
6434                 current_function = old_current_function;
6435                 label_pop_to(label_stack_top);
6436         }
6437
6438         assert(current_scope == &function->parameters);
6439         scope_pop(old_scope);
6440         environment_pop_to(top);
6441 }
6442
6443 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
6444                                   source_position_t *source_position,
6445                                   const symbol_t *symbol)
6446 {
6447         type_t *type = allocate_type_zero(TYPE_BITFIELD);
6448
6449         type->bitfield.base_type       = base_type;
6450         type->bitfield.size_expression = size;
6451
6452         il_size_t bit_size;
6453         type_t *skipped_type = skip_typeref(base_type);
6454         if (!is_type_integer(skipped_type)) {
6455                 errorf(HERE, "bitfield base type '%T' is not an integer type",
6456                         base_type);
6457                 bit_size = 0;
6458         } else {
6459                 bit_size = skipped_type->base.size * 8;
6460         }
6461
6462         if (is_constant_expression(size)) {
6463                 long v = fold_constant(size);
6464
6465                 if (v < 0) {
6466                         errorf(source_position, "negative width in bit-field '%Y'", symbol);
6467                 } else if (v == 0) {
6468                         errorf(source_position, "zero width for bit-field '%Y'", symbol);
6469                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
6470                         errorf(source_position, "width of '%Y' exceeds its type", symbol);
6471                 } else {
6472                         type->bitfield.bit_size = v;
6473                 }
6474         }
6475
6476         return type;
6477 }
6478
6479 static entity_t *find_compound_entry(compound_t *compound, symbol_t *symbol)
6480 {
6481         entity_t *iter = compound->members.entities;
6482         for (; iter != NULL; iter = iter->base.next) {
6483                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
6484                         continue;
6485
6486                 if (iter->base.symbol == symbol) {
6487                         return iter;
6488                 } else if (iter->base.symbol == NULL) {
6489                         type_t *type = skip_typeref(iter->declaration.type);
6490                         if (is_type_compound(type)) {
6491                                 entity_t *result
6492                                         = find_compound_entry(type->compound.compound, symbol);
6493                                 if (result != NULL)
6494                                         return result;
6495                         }
6496                         continue;
6497                 }
6498         }
6499
6500         return NULL;
6501 }
6502
6503 static void parse_compound_declarators(compound_t *compound,
6504                 const declaration_specifiers_t *specifiers)
6505 {
6506         while (true) {
6507                 entity_t *entity;
6508
6509                 if (token.type == ':') {
6510                         source_position_t source_position = *HERE;
6511                         next_token();
6512
6513                         type_t *base_type = specifiers->type;
6514                         expression_t *size = parse_constant_expression();
6515
6516                         type_t *type = make_bitfield_type(base_type, size,
6517                                         &source_position, sym_anonymous);
6518
6519                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
6520                         entity->base.namespc                       = NAMESPACE_NORMAL;
6521                         entity->base.source_position               = source_position;
6522                         entity->declaration.declared_storage_class = STORAGE_CLASS_NONE;
6523                         entity->declaration.storage_class          = STORAGE_CLASS_NONE;
6524                         entity->declaration.modifiers              = specifiers->modifiers;
6525                         entity->declaration.type                   = type;
6526                         append_entity(&compound->members, entity);
6527                 } else {
6528                         entity = parse_declarator(specifiers,
6529                                         DECL_MAY_BE_ABSTRACT | DECL_CREATE_COMPOUND_MEMBER);
6530                         if (entity->kind == ENTITY_TYPEDEF) {
6531                                 errorf(&entity->base.source_position,
6532                                                 "typedef not allowed as compound member");
6533                         } else {
6534                                 assert(entity->kind == ENTITY_COMPOUND_MEMBER);
6535
6536                                 /* make sure we don't define a symbol multiple times */
6537                                 symbol_t *symbol = entity->base.symbol;
6538                                 if (symbol != NULL) {
6539                                         entity_t *prev = find_compound_entry(compound, symbol);
6540                                         if (prev != NULL) {
6541                                                 errorf(&entity->base.source_position,
6542                                                                 "multiple declarations of symbol '%Y' (declared %P)",
6543                                                                 symbol, &prev->base.source_position);
6544                                         }
6545                                 }
6546
6547                                 if (token.type == ':') {
6548                                         source_position_t source_position = *HERE;
6549                                         next_token();
6550                                         expression_t *size = parse_constant_expression();
6551
6552                                         type_t *type          = entity->declaration.type;
6553                                         type_t *bitfield_type = make_bitfield_type(type, size,
6554                                                         &source_position, entity->base.symbol);
6555                                         entity->declaration.type = bitfield_type;
6556                                 } else {
6557                                         type_t *orig_type = entity->declaration.type;
6558                                         type_t *type      = skip_typeref(orig_type);
6559                                         if (is_type_function(type)) {
6560                                                 errorf(&entity->base.source_position,
6561                                                                 "compound member '%Y' must not have function type '%T'",
6562                                                                 entity->base.symbol, orig_type);
6563                                         } else if (is_type_incomplete(type)) {
6564                                                 /* §6.7.2.1:16 flexible array member */
6565                                                 if (is_type_array(type) &&
6566                                                                 token.type == ';'   &&
6567                                                                 look_ahead(1)->type == '}') {
6568                                                         compound->has_flexible_member = true;
6569                                                 } else {
6570                                                         errorf(&entity->base.source_position,
6571                                                                         "compound member '%Y' has incomplete type '%T'",
6572                                                                         entity->base.symbol, orig_type);
6573                                                 }
6574                                         }
6575                                 }
6576
6577                                 append_entity(&compound->members, entity);
6578                         }
6579                 }
6580
6581                 if (token.type != ',')
6582                         break;
6583                 next_token();
6584         }
6585         expect(';', end_error);
6586
6587 end_error:
6588         anonymous_entity = NULL;
6589 }
6590
6591 static void parse_compound_type_entries(compound_t *compound)
6592 {
6593         eat('{');
6594         add_anchor_token('}');
6595
6596         while (token.type != '}') {
6597                 if (token.type == T_EOF) {
6598                         errorf(HERE, "EOF while parsing struct");
6599                         break;
6600                 }
6601                 declaration_specifiers_t specifiers;
6602                 memset(&specifiers, 0, sizeof(specifiers));
6603                 parse_declaration_specifiers(&specifiers);
6604
6605                 parse_compound_declarators(compound, &specifiers);
6606         }
6607         rem_anchor_token('}');
6608         next_token();
6609
6610         /* §6.7.2.1:7 */
6611         compound->complete = true;
6612 }
6613
6614 static type_t *parse_typename(void)
6615 {
6616         declaration_specifiers_t specifiers;
6617         memset(&specifiers, 0, sizeof(specifiers));
6618         parse_declaration_specifiers(&specifiers);
6619         if (specifiers.storage_class != STORAGE_CLASS_NONE ||
6620                         specifiers.thread_local) {
6621                 /* TODO: improve error message, user does probably not know what a
6622                  * storage class is...
6623                  */
6624                 errorf(HERE, "typename may not have a storage class");
6625         }
6626
6627         type_t *result = parse_abstract_declarator(specifiers.type);
6628
6629         return result;
6630 }
6631
6632
6633
6634
6635 typedef expression_t* (*parse_expression_function)(void);
6636 typedef expression_t* (*parse_expression_infix_function)(expression_t *left);
6637
6638 typedef struct expression_parser_function_t expression_parser_function_t;
6639 struct expression_parser_function_t {
6640         parse_expression_function        parser;
6641         precedence_t                     infix_precedence;
6642         parse_expression_infix_function  infix_parser;
6643 };
6644
6645 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
6646
6647 /**
6648  * Prints an error message if an expression was expected but not read
6649  */
6650 static expression_t *expected_expression_error(void)
6651 {
6652         /* skip the error message if the error token was read */
6653         if (token.type != T_ERROR) {
6654                 errorf(HERE, "expected expression, got token %K", &token);
6655         }
6656         next_token();
6657
6658         return create_invalid_expression();
6659 }
6660
6661 /**
6662  * Parse a string constant.
6663  */
6664 static expression_t *parse_string_const(void)
6665 {
6666         wide_string_t wres;
6667         if (token.type == T_STRING_LITERAL) {
6668                 string_t res = token.v.string;
6669                 next_token();
6670                 while (token.type == T_STRING_LITERAL) {
6671                         res = concat_strings(&res, &token.v.string);
6672                         next_token();
6673                 }
6674                 if (token.type != T_WIDE_STRING_LITERAL) {
6675                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
6676                         /* note: that we use type_char_ptr here, which is already the
6677                          * automatic converted type. revert_automatic_type_conversion
6678                          * will construct the array type */
6679                         cnst->base.type    = warning.write_strings ? type_const_char_ptr : type_char_ptr;
6680                         cnst->string.value = res;
6681                         return cnst;
6682                 }
6683
6684                 wres = concat_string_wide_string(&res, &token.v.wide_string);
6685         } else {
6686                 wres = token.v.wide_string;
6687         }
6688         next_token();
6689
6690         for (;;) {
6691                 switch (token.type) {
6692                         case T_WIDE_STRING_LITERAL:
6693                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
6694                                 break;
6695
6696                         case T_STRING_LITERAL:
6697                                 wres = concat_wide_string_string(&wres, &token.v.string);
6698                                 break;
6699
6700                         default: {
6701                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
6702                                 cnst->base.type         = warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
6703                                 cnst->wide_string.value = wres;
6704                                 return cnst;
6705                         }
6706                 }
6707                 next_token();
6708         }
6709 }
6710
6711 /**
6712  * Parse a boolean constant.
6713  */
6714 static expression_t *parse_bool_const(bool value)
6715 {
6716         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6717         cnst->base.type          = type_bool;
6718         cnst->conste.v.int_value = value;
6719
6720         next_token();
6721
6722         return cnst;
6723 }
6724
6725 /**
6726  * Parse an integer constant.
6727  */
6728 static expression_t *parse_int_const(void)
6729 {
6730         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6731         cnst->base.type          = token.datatype;
6732         cnst->conste.v.int_value = token.v.intvalue;
6733
6734         next_token();
6735
6736         return cnst;
6737 }
6738
6739 /**
6740  * Parse a character constant.
6741  */
6742 static expression_t *parse_character_constant(void)
6743 {
6744         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
6745         cnst->base.type          = token.datatype;
6746         cnst->conste.v.character = token.v.string;
6747
6748         if (cnst->conste.v.character.size != 1) {
6749                 if (!GNU_MODE) {
6750                         errorf(HERE, "more than 1 character in character constant");
6751                 } else if (warning.multichar) {
6752                         warningf(HERE, "multi-character character constant");
6753                 }
6754         }
6755         next_token();
6756
6757         return cnst;
6758 }
6759
6760 /**
6761  * Parse a wide character constant.
6762  */
6763 static expression_t *parse_wide_character_constant(void)
6764 {
6765         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
6766         cnst->base.type               = token.datatype;
6767         cnst->conste.v.wide_character = token.v.wide_string;
6768
6769         if (cnst->conste.v.wide_character.size != 1) {
6770                 if (!GNU_MODE) {
6771                         errorf(HERE, "more than 1 character in character constant");
6772                 } else if (warning.multichar) {
6773                         warningf(HERE, "multi-character character constant");
6774                 }
6775         }
6776         next_token();
6777
6778         return cnst;
6779 }
6780
6781 /**
6782  * Parse a float constant.
6783  */
6784 static expression_t *parse_float_const(void)
6785 {
6786         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6787         cnst->base.type            = token.datatype;
6788         cnst->conste.v.float_value = token.v.floatvalue;
6789
6790         next_token();
6791
6792         return cnst;
6793 }
6794
6795 static entity_t *create_implicit_function(symbol_t *symbol,
6796                 const source_position_t *source_position)
6797 {
6798         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION);
6799         ntype->function.return_type            = type_int;
6800         ntype->function.unspecified_parameters = true;
6801         ntype->function.linkage                = LINKAGE_C;
6802
6803         type_t *type = typehash_insert(ntype);
6804         if (type != ntype) {
6805                 free_type(ntype);
6806         }
6807
6808         entity_t *entity = allocate_entity_zero(ENTITY_FUNCTION);
6809         entity->declaration.storage_class          = STORAGE_CLASS_EXTERN;
6810         entity->declaration.declared_storage_class = STORAGE_CLASS_EXTERN;
6811         entity->declaration.type                   = type;
6812         entity->declaration.implicit               = true;
6813         entity->base.symbol                        = symbol;
6814         entity->base.source_position               = *source_position;
6815
6816         bool strict_prototypes_old = warning.strict_prototypes;
6817         warning.strict_prototypes  = false;
6818         record_entity(entity, false);
6819         warning.strict_prototypes = strict_prototypes_old;
6820
6821         return entity;
6822 }
6823
6824 /**
6825  * Creates a return_type (func)(argument_type) function type if not
6826  * already exists.
6827  */
6828 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
6829                                     type_t *argument_type2)
6830 {
6831         function_parameter_t *parameter2
6832                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
6833         memset(parameter2, 0, sizeof(parameter2[0]));
6834         parameter2->type = argument_type2;
6835
6836         function_parameter_t *parameter1
6837                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
6838         memset(parameter1, 0, sizeof(parameter1[0]));
6839         parameter1->type = argument_type1;
6840         parameter1->next = parameter2;
6841
6842         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6843         type->function.return_type = return_type;
6844         type->function.parameters  = parameter1;
6845
6846         type_t *result = typehash_insert(type);
6847         if (result != type) {
6848                 free_type(type);
6849         }
6850
6851         return result;
6852 }
6853
6854 /**
6855  * Creates a return_type (func)(argument_type) function type if not
6856  * already exists.
6857  *
6858  * @param return_type    the return type
6859  * @param argument_type  the argument type
6860  */
6861 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
6862 {
6863         function_parameter_t *parameter
6864                 = obstack_alloc(type_obst, sizeof(parameter[0]));
6865         memset(parameter, 0, sizeof(parameter[0]));
6866         parameter->type = argument_type;
6867
6868         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6869         type->function.return_type = return_type;
6870         type->function.parameters  = parameter;
6871
6872         type_t *result = typehash_insert(type);
6873         if (result != type) {
6874                 free_type(type);
6875         }
6876
6877         return result;
6878 }
6879
6880 static type_t *make_function_0_type(type_t *return_type)
6881 {
6882         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6883         type->function.return_type = return_type;
6884         type->function.parameters  = NULL;
6885
6886         type_t *result = typehash_insert(type);
6887         if (result != type) {
6888                 free_type(type);
6889         }
6890
6891         return result;
6892 }
6893
6894 /**
6895  * Creates a function type for some function like builtins.
6896  *
6897  * @param symbol   the symbol describing the builtin
6898  */
6899 static type_t *get_builtin_symbol_type(symbol_t *symbol)
6900 {
6901         switch (symbol->ID) {
6902         case T___builtin_alloca:
6903                 return make_function_1_type(type_void_ptr, type_size_t);
6904         case T___builtin_huge_val:
6905                 return make_function_0_type(type_double);
6906         case T___builtin_inf:
6907                 return make_function_0_type(type_double);
6908         case T___builtin_inff:
6909                 return make_function_0_type(type_float);
6910         case T___builtin_infl:
6911                 return make_function_0_type(type_long_double);
6912         case T___builtin_nan:
6913                 return make_function_1_type(type_double, type_char_ptr);
6914         case T___builtin_nanf:
6915                 return make_function_1_type(type_float, type_char_ptr);
6916         case T___builtin_nanl:
6917                 return make_function_1_type(type_long_double, type_char_ptr);
6918         case T___builtin_va_end:
6919                 return make_function_1_type(type_void, type_valist);
6920         case T___builtin_expect:
6921                 return make_function_2_type(type_long, type_long, type_long);
6922         default:
6923                 internal_errorf(HERE, "not implemented builtin identifier found");
6924         }
6925 }
6926
6927 /**
6928  * Performs automatic type cast as described in § 6.3.2.1.
6929  *
6930  * @param orig_type  the original type
6931  */
6932 static type_t *automatic_type_conversion(type_t *orig_type)
6933 {
6934         type_t *type = skip_typeref(orig_type);
6935         if (is_type_array(type)) {
6936                 array_type_t *array_type   = &type->array;
6937                 type_t       *element_type = array_type->element_type;
6938                 unsigned      qualifiers   = array_type->base.qualifiers;
6939
6940                 return make_pointer_type(element_type, qualifiers);
6941         }
6942
6943         if (is_type_function(type)) {
6944                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6945         }
6946
6947         return orig_type;
6948 }
6949
6950 /**
6951  * reverts the automatic casts of array to pointer types and function
6952  * to function-pointer types as defined § 6.3.2.1
6953  */
6954 type_t *revert_automatic_type_conversion(const expression_t *expression)
6955 {
6956         switch (expression->kind) {
6957                 case EXPR_REFERENCE: {
6958                         entity_t *entity = expression->reference.entity;
6959                         if (is_declaration(entity)) {
6960                                 return entity->declaration.type;
6961                         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6962                                 return entity->enum_value.enum_type;
6963                         } else {
6964                                 panic("no declaration or enum in reference");
6965                         }
6966                 }
6967
6968                 case EXPR_SELECT: {
6969                         entity_t *entity = expression->select.compound_entry;
6970                         assert(is_declaration(entity));
6971                         type_t   *type   = entity->declaration.type;
6972                         return get_qualified_type(type,
6973                                         expression->base.type->base.qualifiers);
6974                 }
6975
6976                 case EXPR_UNARY_DEREFERENCE: {
6977                         const expression_t *const value = expression->unary.value;
6978                         type_t             *const type  = skip_typeref(value->base.type);
6979                         if (!is_type_pointer(type))
6980                                 return type_error_type;
6981                         return type->pointer.points_to;
6982                 }
6983
6984                 case EXPR_BUILTIN_SYMBOL:
6985                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
6986
6987                 case EXPR_ARRAY_ACCESS: {
6988                         const expression_t *array_ref = expression->array_access.array_ref;
6989                         type_t             *type_left = skip_typeref(array_ref->base.type);
6990                         if (!is_type_pointer(type_left))
6991                                 return type_error_type;
6992                         return type_left->pointer.points_to;
6993                 }
6994
6995                 case EXPR_STRING_LITERAL: {
6996                         size_t size = expression->string.value.size;
6997                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
6998                 }
6999
7000                 case EXPR_WIDE_STRING_LITERAL: {
7001                         size_t size = expression->wide_string.value.size;
7002                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
7003                 }
7004
7005                 case EXPR_COMPOUND_LITERAL:
7006                         return expression->compound_literal.type;
7007
7008                 default:
7009                         return expression->base.type;
7010         }
7011 }
7012
7013 static expression_t *parse_reference(void)
7014 {
7015         symbol_t *const symbol = token.v.symbol;
7016
7017         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
7018
7019         if (entity == NULL) {
7020                 if (!strict_mode && look_ahead(1)->type == '(') {
7021                         /* an implicitly declared function */
7022                         if (warning.error_implicit_function_declaration) {
7023                                 errorf(HERE, "implicit declaration of function '%Y'", symbol);
7024                         } else if (warning.implicit_function_declaration) {
7025                                 warningf(HERE, "implicit declaration of function '%Y'", symbol);
7026                         }
7027
7028                         entity = create_implicit_function(symbol, HERE);
7029                 } else {
7030                         errorf(HERE, "unknown identifier '%Y' found.", symbol);
7031                         entity = create_error_entity(symbol, ENTITY_VARIABLE);
7032                 }
7033         }
7034
7035         type_t *orig_type;
7036
7037         if (is_declaration(entity)) {
7038                 orig_type = entity->declaration.type;
7039         } else if (entity->kind == ENTITY_ENUM_VALUE) {
7040                 orig_type = entity->enum_value.enum_type;
7041         } else if (entity->kind == ENTITY_TYPEDEF) {
7042                 errorf(HERE, "encountered typedef name '%Y' while parsing expression",
7043                         symbol);
7044                 next_token();
7045                 return create_invalid_expression();
7046         } else {
7047                 panic("expected declaration or enum value in reference");
7048         }
7049
7050         /* we always do the auto-type conversions; the & and sizeof parser contains
7051          * code to revert this! */
7052         type_t *type = automatic_type_conversion(orig_type);
7053
7054         expression_kind_t kind = EXPR_REFERENCE;
7055         if (entity->kind == ENTITY_ENUM_VALUE)
7056                 kind = EXPR_REFERENCE_ENUM_VALUE;
7057
7058         expression_t *expression     = allocate_expression_zero(kind);
7059         expression->reference.entity = entity;
7060         expression->base.type        = type;
7061
7062         /* this declaration is used */
7063         if (is_declaration(entity)) {
7064                 entity->declaration.used = true;
7065         }
7066
7067         if (entity->base.parent_scope != file_scope
7068                 && entity->base.parent_scope->depth < current_function->parameters.depth
7069                 && is_type_valid(orig_type) && !is_type_function(orig_type)) {
7070                 if (entity->kind == ENTITY_VARIABLE) {
7071                         /* access of a variable from an outer function */
7072                         entity->variable.address_taken = true;
7073                 } else if (entity->kind == ENTITY_PARAMETER) {
7074                         entity->parameter.address_taken = true;
7075                 }
7076                 current_function->need_closure = true;
7077         }
7078
7079         /* check for deprecated functions */
7080         if (warning.deprecated_declarations
7081                 && is_declaration(entity)
7082                 && entity->declaration.modifiers & DM_DEPRECATED) {
7083                 declaration_t *declaration = &entity->declaration;
7084
7085                 char const *const prefix = entity->kind == ENTITY_FUNCTION ?
7086                         "function" : "variable";
7087
7088                 if (declaration->deprecated_string != NULL) {
7089                         warningf(HERE, "%s '%Y' is deprecated (declared %P): \"%s\"",
7090                                  prefix, entity->base.symbol, &entity->base.source_position,
7091                                  declaration->deprecated_string);
7092                 } else {
7093                         warningf(HERE, "%s '%Y' is deprecated (declared %P)", prefix,
7094                                  entity->base.symbol, &entity->base.source_position);
7095                 }
7096         }
7097
7098         if (warning.init_self && entity == current_init_decl && !in_type_prop
7099             && entity->kind == ENTITY_VARIABLE) {
7100                 current_init_decl = NULL;
7101                 warningf(HERE, "variable '%#T' is initialized by itself",
7102                          entity->declaration.type, entity->base.symbol);
7103         }
7104
7105         next_token();
7106         return expression;
7107 }
7108
7109 static bool semantic_cast(expression_t *cast)
7110 {
7111         expression_t            *expression      = cast->unary.value;
7112         type_t                  *orig_dest_type  = cast->base.type;
7113         type_t                  *orig_type_right = expression->base.type;
7114         type_t            const *dst_type        = skip_typeref(orig_dest_type);
7115         type_t            const *src_type        = skip_typeref(orig_type_right);
7116         source_position_t const *pos             = &cast->base.source_position;
7117
7118         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
7119         if (dst_type == type_void)
7120                 return true;
7121
7122         /* only integer and pointer can be casted to pointer */
7123         if (is_type_pointer(dst_type)  &&
7124             !is_type_pointer(src_type) &&
7125             !is_type_integer(src_type) &&
7126             is_type_valid(src_type)) {
7127                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
7128                 return false;
7129         }
7130
7131         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
7132                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
7133                 return false;
7134         }
7135
7136         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
7137                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
7138                 return false;
7139         }
7140
7141         if (warning.cast_qual &&
7142             is_type_pointer(src_type) &&
7143             is_type_pointer(dst_type)) {
7144                 type_t *src = skip_typeref(src_type->pointer.points_to);
7145                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
7146                 unsigned missing_qualifiers =
7147                         src->base.qualifiers & ~dst->base.qualifiers;
7148                 if (missing_qualifiers != 0) {
7149                         warningf(pos,
7150                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
7151                                  missing_qualifiers, orig_type_right);
7152                 }
7153         }
7154         return true;
7155 }
7156
7157 static expression_t *parse_compound_literal(type_t *type)
7158 {
7159         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
7160
7161         parse_initializer_env_t env;
7162         env.type             = type;
7163         env.entity           = NULL;
7164         env.must_be_constant = false;
7165         initializer_t *initializer = parse_initializer(&env);
7166         type = env.type;
7167
7168         expression->compound_literal.initializer = initializer;
7169         expression->compound_literal.type        = type;
7170         expression->base.type                    = automatic_type_conversion(type);
7171
7172         return expression;
7173 }
7174
7175 /**
7176  * Parse a cast expression.
7177  */
7178 static expression_t *parse_cast(void)
7179 {
7180         add_anchor_token(')');
7181
7182         source_position_t source_position = token.source_position;
7183
7184         type_t *type = parse_typename();
7185
7186         rem_anchor_token(')');
7187         expect(')', end_error);
7188
7189         if (token.type == '{') {
7190                 return parse_compound_literal(type);
7191         }
7192
7193         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
7194         cast->base.source_position = source_position;
7195
7196         expression_t *value = parse_sub_expression(PREC_CAST);
7197         cast->base.type   = type;
7198         cast->unary.value = value;
7199
7200         if (! semantic_cast(cast)) {
7201                 /* TODO: record the error in the AST. else it is impossible to detect it */
7202         }
7203
7204         return cast;
7205 end_error:
7206         return create_invalid_expression();
7207 }
7208
7209 /**
7210  * Parse a statement expression.
7211  */
7212 static expression_t *parse_statement_expression(void)
7213 {
7214         add_anchor_token(')');
7215
7216         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
7217
7218         statement_t *statement          = parse_compound_statement(true);
7219         statement->compound.stmt_expr   = true;
7220         expression->statement.statement = statement;
7221
7222         /* find last statement and use its type */
7223         type_t *type = type_void;
7224         const statement_t *stmt = statement->compound.statements;
7225         if (stmt != NULL) {
7226                 while (stmt->base.next != NULL)
7227                         stmt = stmt->base.next;
7228
7229                 if (stmt->kind == STATEMENT_EXPRESSION) {
7230                         type = stmt->expression.expression->base.type;
7231                 }
7232         } else if (warning.other) {
7233                 warningf(&expression->base.source_position, "empty statement expression ({})");
7234         }
7235         expression->base.type = type;
7236
7237         rem_anchor_token(')');
7238         expect(')', end_error);
7239
7240 end_error:
7241         return expression;
7242 }
7243
7244 /**
7245  * Parse a parenthesized expression.
7246  */
7247 static expression_t *parse_parenthesized_expression(void)
7248 {
7249         eat('(');
7250
7251         switch (token.type) {
7252         case '{':
7253                 /* gcc extension: a statement expression */
7254                 return parse_statement_expression();
7255
7256         TYPE_QUALIFIERS
7257         TYPE_SPECIFIERS
7258                 return parse_cast();
7259         case T_IDENTIFIER:
7260                 if (is_typedef_symbol(token.v.symbol)) {
7261                         return parse_cast();
7262                 }
7263         }
7264
7265         add_anchor_token(')');
7266         expression_t *result = parse_expression();
7267         result->base.parenthesized = true;
7268         rem_anchor_token(')');
7269         expect(')', end_error);
7270
7271 end_error:
7272         return result;
7273 }
7274
7275 static expression_t *parse_function_keyword(void)
7276 {
7277         /* TODO */
7278
7279         if (current_function == NULL) {
7280                 errorf(HERE, "'__func__' used outside of a function");
7281         }
7282
7283         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7284         expression->base.type     = type_char_ptr;
7285         expression->funcname.kind = FUNCNAME_FUNCTION;
7286
7287         next_token();
7288
7289         return expression;
7290 }
7291
7292 static expression_t *parse_pretty_function_keyword(void)
7293 {
7294         if (current_function == NULL) {
7295                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
7296         }
7297
7298         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7299         expression->base.type     = type_char_ptr;
7300         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
7301
7302         eat(T___PRETTY_FUNCTION__);
7303
7304         return expression;
7305 }
7306
7307 static expression_t *parse_funcsig_keyword(void)
7308 {
7309         if (current_function == NULL) {
7310                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
7311         }
7312
7313         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7314         expression->base.type     = type_char_ptr;
7315         expression->funcname.kind = FUNCNAME_FUNCSIG;
7316
7317         eat(T___FUNCSIG__);
7318
7319         return expression;
7320 }
7321
7322 static expression_t *parse_funcdname_keyword(void)
7323 {
7324         if (current_function == NULL) {
7325                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
7326         }
7327
7328         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7329         expression->base.type     = type_char_ptr;
7330         expression->funcname.kind = FUNCNAME_FUNCDNAME;
7331
7332         eat(T___FUNCDNAME__);
7333
7334         return expression;
7335 }
7336
7337 static designator_t *parse_designator(void)
7338 {
7339         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
7340         result->source_position = *HERE;
7341
7342         if (token.type != T_IDENTIFIER) {
7343                 parse_error_expected("while parsing member designator",
7344                                      T_IDENTIFIER, NULL);
7345                 return NULL;
7346         }
7347         result->symbol = token.v.symbol;
7348         next_token();
7349
7350         designator_t *last_designator = result;
7351         while (true) {
7352                 if (token.type == '.') {
7353                         next_token();
7354                         if (token.type != T_IDENTIFIER) {
7355                                 parse_error_expected("while parsing member designator",
7356                                                      T_IDENTIFIER, NULL);
7357                                 return NULL;
7358                         }
7359                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7360                         designator->source_position = *HERE;
7361                         designator->symbol          = token.v.symbol;
7362                         next_token();
7363
7364                         last_designator->next = designator;
7365                         last_designator       = designator;
7366                         continue;
7367                 }
7368                 if (token.type == '[') {
7369                         next_token();
7370                         add_anchor_token(']');
7371                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7372                         designator->source_position = *HERE;
7373                         designator->array_index     = parse_expression();
7374                         rem_anchor_token(']');
7375                         expect(']', end_error);
7376                         if (designator->array_index == NULL) {
7377                                 return NULL;
7378                         }
7379
7380                         last_designator->next = designator;
7381                         last_designator       = designator;
7382                         continue;
7383                 }
7384                 break;
7385         }
7386
7387         return result;
7388 end_error:
7389         return NULL;
7390 }
7391
7392 /**
7393  * Parse the __builtin_offsetof() expression.
7394  */
7395 static expression_t *parse_offsetof(void)
7396 {
7397         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
7398         expression->base.type    = type_size_t;
7399
7400         eat(T___builtin_offsetof);
7401
7402         expect('(', end_error);
7403         add_anchor_token(',');
7404         type_t *type = parse_typename();
7405         rem_anchor_token(',');
7406         expect(',', end_error);
7407         add_anchor_token(')');
7408         designator_t *designator = parse_designator();
7409         rem_anchor_token(')');
7410         expect(')', end_error);
7411
7412         expression->offsetofe.type       = type;
7413         expression->offsetofe.designator = designator;
7414
7415         type_path_t path;
7416         memset(&path, 0, sizeof(path));
7417         path.top_type = type;
7418         path.path     = NEW_ARR_F(type_path_entry_t, 0);
7419
7420         descend_into_subtype(&path);
7421
7422         if (!walk_designator(&path, designator, true)) {
7423                 return create_invalid_expression();
7424         }
7425
7426         DEL_ARR_F(path.path);
7427
7428         return expression;
7429 end_error:
7430         return create_invalid_expression();
7431 }
7432
7433 /**
7434  * Parses a _builtin_va_start() expression.
7435  */
7436 static expression_t *parse_va_start(void)
7437 {
7438         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
7439
7440         eat(T___builtin_va_start);
7441
7442         expect('(', end_error);
7443         add_anchor_token(',');
7444         expression->va_starte.ap = parse_assignment_expression();
7445         rem_anchor_token(',');
7446         expect(',', end_error);
7447         expression_t *const expr = parse_assignment_expression();
7448         if (expr->kind == EXPR_REFERENCE) {
7449                 entity_t *const entity = expr->reference.entity;
7450                 if (entity->base.parent_scope != &current_function->parameters
7451                                 || entity->base.next != NULL
7452                                 || entity->kind != ENTITY_PARAMETER) {
7453                         errorf(&expr->base.source_position,
7454                                "second argument of 'va_start' must be last parameter of the current function");
7455                 } else {
7456                         expression->va_starte.parameter = &entity->variable;
7457                 }
7458                 expect(')', end_error);
7459                 return expression;
7460         }
7461         expect(')', end_error);
7462 end_error:
7463         return create_invalid_expression();
7464 }
7465
7466 /**
7467  * Parses a _builtin_va_arg() expression.
7468  */
7469 static expression_t *parse_va_arg(void)
7470 {
7471         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
7472
7473         eat(T___builtin_va_arg);
7474
7475         expect('(', end_error);
7476         expression->va_arge.ap = parse_assignment_expression();
7477         expect(',', end_error);
7478         expression->base.type = parse_typename();
7479         expect(')', end_error);
7480
7481         return expression;
7482 end_error:
7483         return create_invalid_expression();
7484 }
7485
7486 static expression_t *parse_builtin_symbol(void)
7487 {
7488         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
7489
7490         symbol_t *symbol = token.v.symbol;
7491
7492         expression->builtin_symbol.symbol = symbol;
7493         next_token();
7494
7495         type_t *type = get_builtin_symbol_type(symbol);
7496         type = automatic_type_conversion(type);
7497
7498         expression->base.type = type;
7499         return expression;
7500 }
7501
7502 /**
7503  * Parses a __builtin_constant() expression.
7504  */
7505 static expression_t *parse_builtin_constant(void)
7506 {
7507         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
7508
7509         eat(T___builtin_constant_p);
7510
7511         expect('(', end_error);
7512         add_anchor_token(')');
7513         expression->builtin_constant.value = parse_assignment_expression();
7514         rem_anchor_token(')');
7515         expect(')', end_error);
7516         expression->base.type = type_int;
7517
7518         return expression;
7519 end_error:
7520         return create_invalid_expression();
7521 }
7522
7523 /**
7524  * Parses a __builtin_prefetch() expression.
7525  */
7526 static expression_t *parse_builtin_prefetch(void)
7527 {
7528         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
7529
7530         eat(T___builtin_prefetch);
7531
7532         expect('(', end_error);
7533         add_anchor_token(')');
7534         expression->builtin_prefetch.adr = parse_assignment_expression();
7535         if (token.type == ',') {
7536                 next_token();
7537                 expression->builtin_prefetch.rw = parse_assignment_expression();
7538         }
7539         if (token.type == ',') {
7540                 next_token();
7541                 expression->builtin_prefetch.locality = parse_assignment_expression();
7542         }
7543         rem_anchor_token(')');
7544         expect(')', end_error);
7545         expression->base.type = type_void;
7546
7547         return expression;
7548 end_error:
7549         return create_invalid_expression();
7550 }
7551
7552 /**
7553  * Parses a __builtin_is_*() compare expression.
7554  */
7555 static expression_t *parse_compare_builtin(void)
7556 {
7557         expression_t *expression;
7558
7559         switch (token.type) {
7560         case T___builtin_isgreater:
7561                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
7562                 break;
7563         case T___builtin_isgreaterequal:
7564                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
7565                 break;
7566         case T___builtin_isless:
7567                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
7568                 break;
7569         case T___builtin_islessequal:
7570                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
7571                 break;
7572         case T___builtin_islessgreater:
7573                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
7574                 break;
7575         case T___builtin_isunordered:
7576                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
7577                 break;
7578         default:
7579                 internal_errorf(HERE, "invalid compare builtin found");
7580         }
7581         expression->base.source_position = *HERE;
7582         next_token();
7583
7584         expect('(', end_error);
7585         expression->binary.left = parse_assignment_expression();
7586         expect(',', end_error);
7587         expression->binary.right = parse_assignment_expression();
7588         expect(')', end_error);
7589
7590         type_t *const orig_type_left  = expression->binary.left->base.type;
7591         type_t *const orig_type_right = expression->binary.right->base.type;
7592
7593         type_t *const type_left  = skip_typeref(orig_type_left);
7594         type_t *const type_right = skip_typeref(orig_type_right);
7595         if (!is_type_float(type_left) && !is_type_float(type_right)) {
7596                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7597                         type_error_incompatible("invalid operands in comparison",
7598                                 &expression->base.source_position, orig_type_left, orig_type_right);
7599                 }
7600         } else {
7601                 semantic_comparison(&expression->binary);
7602         }
7603
7604         return expression;
7605 end_error:
7606         return create_invalid_expression();
7607 }
7608
7609 #if 0
7610 /**
7611  * Parses a __builtin_expect(, end_error) expression.
7612  */
7613 static expression_t *parse_builtin_expect(void, end_error)
7614 {
7615         expression_t *expression
7616                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
7617
7618         eat(T___builtin_expect);
7619
7620         expect('(', end_error);
7621         expression->binary.left = parse_assignment_expression();
7622         expect(',', end_error);
7623         expression->binary.right = parse_constant_expression();
7624         expect(')', end_error);
7625
7626         expression->base.type = expression->binary.left->base.type;
7627
7628         return expression;
7629 end_error:
7630         return create_invalid_expression();
7631 }
7632 #endif
7633
7634 /**
7635  * Parses a MS assume() expression.
7636  */
7637 static expression_t *parse_assume(void)
7638 {
7639         expression_t *expression = allocate_expression_zero(EXPR_UNARY_ASSUME);
7640
7641         eat(T__assume);
7642
7643         expect('(', end_error);
7644         add_anchor_token(')');
7645         expression->unary.value = parse_assignment_expression();
7646         rem_anchor_token(')');
7647         expect(')', end_error);
7648
7649         expression->base.type = type_void;
7650         return expression;
7651 end_error:
7652         return create_invalid_expression();
7653 }
7654
7655 /**
7656  * Return the declaration for a given label symbol or create a new one.
7657  *
7658  * @param symbol  the symbol of the label
7659  */
7660 static label_t *get_label(symbol_t *symbol)
7661 {
7662         entity_t *label;
7663         assert(current_function != NULL);
7664
7665         label = get_entity(symbol, NAMESPACE_LABEL);
7666         /* if we found a local label, we already created the declaration */
7667         if (label != NULL && label->kind == ENTITY_LOCAL_LABEL) {
7668                 if (label->base.parent_scope != current_scope) {
7669                         assert(label->base.parent_scope->depth < current_scope->depth);
7670                         current_function->goto_to_outer = true;
7671                 }
7672                 return &label->label;
7673         }
7674
7675         label = get_entity(symbol, NAMESPACE_LABEL);
7676         /* if we found a label in the same function, then we already created the
7677          * declaration */
7678         if (label != NULL
7679                         && label->base.parent_scope == &current_function->parameters) {
7680                 return &label->label;
7681         }
7682
7683         /* otherwise we need to create a new one */
7684         label               = allocate_entity_zero(ENTITY_LABEL);
7685         label->base.namespc = NAMESPACE_LABEL;
7686         label->base.symbol  = symbol;
7687
7688         label_push(label);
7689
7690         return &label->label;
7691 }
7692
7693 /**
7694  * Parses a GNU && label address expression.
7695  */
7696 static expression_t *parse_label_address(void)
7697 {
7698         source_position_t source_position = token.source_position;
7699         eat(T_ANDAND);
7700         if (token.type != T_IDENTIFIER) {
7701                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
7702                 goto end_error;
7703         }
7704         symbol_t *symbol = token.v.symbol;
7705         next_token();
7706
7707         label_t *label       = get_label(symbol);
7708         label->used          = true;
7709         label->address_taken = true;
7710
7711         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
7712         expression->base.source_position = source_position;
7713
7714         /* label address is threaten as a void pointer */
7715         expression->base.type           = type_void_ptr;
7716         expression->label_address.label = label;
7717         return expression;
7718 end_error:
7719         return create_invalid_expression();
7720 }
7721
7722 /**
7723  * Parse a microsoft __noop expression.
7724  */
7725 static expression_t *parse_noop_expression(void)
7726 {
7727         /* the result is a (int)0 */
7728         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
7729         cnst->base.type            = type_int;
7730         cnst->conste.v.int_value   = 0;
7731         cnst->conste.is_ms_noop    = true;
7732
7733         eat(T___noop);
7734
7735         if (token.type == '(') {
7736                 /* parse arguments */
7737                 eat('(');
7738                 add_anchor_token(')');
7739                 add_anchor_token(',');
7740
7741                 if (token.type != ')') {
7742                         while (true) {
7743                                 (void)parse_assignment_expression();
7744                                 if (token.type != ',')
7745                                         break;
7746                                 next_token();
7747                         }
7748                 }
7749         }
7750         rem_anchor_token(',');
7751         rem_anchor_token(')');
7752         expect(')', end_error);
7753
7754 end_error:
7755         return cnst;
7756 }
7757
7758 /**
7759  * Parses a primary expression.
7760  */
7761 static expression_t *parse_primary_expression(void)
7762 {
7763         switch (token.type) {
7764                 case T_false:                    return parse_bool_const(false);
7765                 case T_true:                     return parse_bool_const(true);
7766                 case T_INTEGER:                  return parse_int_const();
7767                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
7768                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
7769                 case T_FLOATINGPOINT:            return parse_float_const();
7770                 case T_STRING_LITERAL:
7771                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
7772                 case T_IDENTIFIER:               return parse_reference();
7773                 case T___FUNCTION__:
7774                 case T___func__:                 return parse_function_keyword();
7775                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
7776                 case T___FUNCSIG__:              return parse_funcsig_keyword();
7777                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
7778                 case T___builtin_offsetof:       return parse_offsetof();
7779                 case T___builtin_va_start:       return parse_va_start();
7780                 case T___builtin_va_arg:         return parse_va_arg();
7781                 case T___builtin_expect:
7782                 case T___builtin_alloca:
7783                 case T___builtin_inf:
7784                 case T___builtin_inff:
7785                 case T___builtin_infl:
7786                 case T___builtin_nan:
7787                 case T___builtin_nanf:
7788                 case T___builtin_nanl:
7789                 case T___builtin_huge_val:
7790                 case T___builtin_va_end:         return parse_builtin_symbol();
7791                 case T___builtin_isgreater:
7792                 case T___builtin_isgreaterequal:
7793                 case T___builtin_isless:
7794                 case T___builtin_islessequal:
7795                 case T___builtin_islessgreater:
7796                 case T___builtin_isunordered:    return parse_compare_builtin();
7797                 case T___builtin_constant_p:     return parse_builtin_constant();
7798                 case T___builtin_prefetch:       return parse_builtin_prefetch();
7799                 case T__assume:                  return parse_assume();
7800                 case T_ANDAND:
7801                         if (GNU_MODE)
7802                                 return parse_label_address();
7803                         break;
7804
7805                 case '(':                        return parse_parenthesized_expression();
7806                 case T___noop:                   return parse_noop_expression();
7807         }
7808
7809         errorf(HERE, "unexpected token %K, expected an expression", &token);
7810         return create_invalid_expression();
7811 }
7812
7813 /**
7814  * Check if the expression has the character type and issue a warning then.
7815  */
7816 static void check_for_char_index_type(const expression_t *expression)
7817 {
7818         type_t       *const type      = expression->base.type;
7819         const type_t *const base_type = skip_typeref(type);
7820
7821         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
7822                         warning.char_subscripts) {
7823                 warningf(&expression->base.source_position,
7824                          "array subscript has type '%T'", type);
7825         }
7826 }
7827
7828 static expression_t *parse_array_expression(expression_t *left)
7829 {
7830         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
7831
7832         eat('[');
7833         add_anchor_token(']');
7834
7835         expression_t *inside = parse_expression();
7836
7837         type_t *const orig_type_left   = left->base.type;
7838         type_t *const orig_type_inside = inside->base.type;
7839
7840         type_t *const type_left   = skip_typeref(orig_type_left);
7841         type_t *const type_inside = skip_typeref(orig_type_inside);
7842
7843         type_t                    *return_type;
7844         array_access_expression_t *array_access = &expression->array_access;
7845         if (is_type_pointer(type_left)) {
7846                 return_type             = type_left->pointer.points_to;
7847                 array_access->array_ref = left;
7848                 array_access->index     = inside;
7849                 check_for_char_index_type(inside);
7850         } else if (is_type_pointer(type_inside)) {
7851                 return_type             = type_inside->pointer.points_to;
7852                 array_access->array_ref = inside;
7853                 array_access->index     = left;
7854                 array_access->flipped   = true;
7855                 check_for_char_index_type(left);
7856         } else {
7857                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
7858                         errorf(HERE,
7859                                 "array access on object with non-pointer types '%T', '%T'",
7860                                 orig_type_left, orig_type_inside);
7861                 }
7862                 return_type             = type_error_type;
7863                 array_access->array_ref = left;
7864                 array_access->index     = inside;
7865         }
7866
7867         expression->base.type = automatic_type_conversion(return_type);
7868
7869         rem_anchor_token(']');
7870         expect(']', end_error);
7871 end_error:
7872         return expression;
7873 }
7874
7875 static expression_t *parse_typeprop(expression_kind_t const kind)
7876 {
7877         expression_t  *tp_expression = allocate_expression_zero(kind);
7878         tp_expression->base.type     = type_size_t;
7879
7880         eat(kind == EXPR_SIZEOF ? T_sizeof : T___alignof__);
7881
7882         /* we only refer to a type property, mark this case */
7883         bool old     = in_type_prop;
7884         in_type_prop = true;
7885
7886         type_t       *orig_type;
7887         expression_t *expression;
7888         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
7889                 next_token();
7890                 add_anchor_token(')');
7891                 orig_type = parse_typename();
7892                 rem_anchor_token(')');
7893                 expect(')', end_error);
7894
7895                 if (token.type == '{') {
7896                         /* It was not sizeof(type) after all.  It is sizeof of an expression
7897                          * starting with a compound literal */
7898                         expression = parse_compound_literal(orig_type);
7899                         goto typeprop_expression;
7900                 }
7901         } else {
7902                 expression = parse_sub_expression(PREC_UNARY);
7903
7904 typeprop_expression:
7905                 tp_expression->typeprop.tp_expression = expression;
7906
7907                 orig_type = revert_automatic_type_conversion(expression);
7908                 expression->base.type = orig_type;
7909         }
7910
7911         tp_expression->typeprop.type   = orig_type;
7912         type_t const* const type       = skip_typeref(orig_type);
7913         char   const* const wrong_type =
7914                 GNU_MODE && is_type_atomic(type, ATOMIC_TYPE_VOID) ? NULL                  :
7915                 is_type_incomplete(type)                           ? "incomplete"          :
7916                 type->kind == TYPE_FUNCTION                        ? "function designator" :
7917                 type->kind == TYPE_BITFIELD                        ? "bitfield"            :
7918                 NULL;
7919         if (wrong_type != NULL) {
7920                 char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7921                 errorf(&tp_expression->base.source_position,
7922                                 "operand of %s expression must not be of %s type '%T'",
7923                                 what, wrong_type, orig_type);
7924         }
7925
7926 end_error:
7927         in_type_prop = old;
7928         return tp_expression;
7929 }
7930
7931 static expression_t *parse_sizeof(void)
7932 {
7933         return parse_typeprop(EXPR_SIZEOF);
7934 }
7935
7936 static expression_t *parse_alignof(void)
7937 {
7938         return parse_typeprop(EXPR_ALIGNOF);
7939 }
7940
7941 static expression_t *parse_select_expression(expression_t *compound)
7942 {
7943         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
7944         select->select.compound = compound;
7945
7946         assert(token.type == '.' || token.type == T_MINUSGREATER);
7947         bool is_pointer = (token.type == T_MINUSGREATER);
7948         next_token();
7949
7950         if (token.type != T_IDENTIFIER) {
7951                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
7952                 return select;
7953         }
7954         symbol_t *symbol = token.v.symbol;
7955         next_token();
7956
7957         type_t *const orig_type = compound->base.type;
7958         type_t *const type      = skip_typeref(orig_type);
7959
7960         type_t *type_left;
7961         bool    saw_error = false;
7962         if (is_type_pointer(type)) {
7963                 if (!is_pointer) {
7964                         errorf(HERE,
7965                                "request for member '%Y' in something not a struct or union, but '%T'",
7966                                symbol, orig_type);
7967                         saw_error = true;
7968                 }
7969                 type_left = skip_typeref(type->pointer.points_to);
7970         } else {
7971                 if (is_pointer && is_type_valid(type)) {
7972                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7973                         saw_error = true;
7974                 }
7975                 type_left = type;
7976         }
7977
7978         entity_t *entry;
7979         if (type_left->kind == TYPE_COMPOUND_STRUCT ||
7980             type_left->kind == TYPE_COMPOUND_UNION) {
7981                 compound_t *compound = type_left->compound.compound;
7982
7983                 if (!compound->complete) {
7984                         errorf(HERE, "request for member '%Y' of incomplete type '%T'",
7985                                symbol, type_left);
7986                         goto create_error_entry;
7987                 }
7988
7989                 entry = find_compound_entry(compound, symbol);
7990                 if (entry == NULL) {
7991                         errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
7992                         goto create_error_entry;
7993                 }
7994         } else {
7995                 if (is_type_valid(type_left) && !saw_error) {
7996                         errorf(HERE,
7997                                "request for member '%Y' in something not a struct or union, but '%T'",
7998                                symbol, type_left);
7999                 }
8000 create_error_entry:
8001                 entry = create_error_entity(symbol, ENTITY_COMPOUND_MEMBER);
8002         }
8003
8004         assert(is_declaration(entry));
8005         select->select.compound_entry = entry;
8006
8007         type_t *entry_type = entry->declaration.type;
8008         type_t *res_type
8009                 = get_qualified_type(entry_type, type_left->base.qualifiers);
8010
8011         /* we always do the auto-type conversions; the & and sizeof parser contains
8012          * code to revert this! */
8013         select->base.type = automatic_type_conversion(res_type);
8014
8015         type_t *skipped = skip_typeref(res_type);
8016         if (skipped->kind == TYPE_BITFIELD) {
8017                 select->base.type = skipped->bitfield.base_type;
8018         }
8019
8020         return select;
8021 }
8022
8023 static void check_call_argument(const function_parameter_t *parameter,
8024                                 call_argument_t *argument, unsigned pos)
8025 {
8026         type_t         *expected_type      = parameter->type;
8027         type_t         *expected_type_skip = skip_typeref(expected_type);
8028         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
8029         expression_t   *arg_expr           = argument->expression;
8030         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
8031
8032         /* handle transparent union gnu extension */
8033         if (is_type_union(expected_type_skip)
8034                         && (expected_type_skip->base.modifiers
8035                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
8036                 compound_t *union_decl  = expected_type_skip->compound.compound;
8037                 type_t     *best_type   = NULL;
8038                 entity_t   *entry       = union_decl->members.entities;
8039                 for ( ; entry != NULL; entry = entry->base.next) {
8040                         assert(is_declaration(entry));
8041                         type_t *decl_type = entry->declaration.type;
8042                         error = semantic_assign(decl_type, arg_expr);
8043                         if (error == ASSIGN_ERROR_INCOMPATIBLE
8044                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
8045                                 continue;
8046
8047                         if (error == ASSIGN_SUCCESS) {
8048                                 best_type = decl_type;
8049                         } else if (best_type == NULL) {
8050                                 best_type = decl_type;
8051                         }
8052                 }
8053
8054                 if (best_type != NULL) {
8055                         expected_type = best_type;
8056                 }
8057         }
8058
8059         error                = semantic_assign(expected_type, arg_expr);
8060         argument->expression = create_implicit_cast(argument->expression,
8061                                                     expected_type);
8062
8063         if (error != ASSIGN_SUCCESS) {
8064                 /* report exact scope in error messages (like "in argument 3") */
8065                 char buf[64];
8066                 snprintf(buf, sizeof(buf), "call argument %u", pos);
8067                 report_assign_error(error, expected_type, arg_expr,     buf,
8068                                                         &arg_expr->base.source_position);
8069         } else if (warning.traditional || warning.conversion) {
8070                 type_t *const promoted_type = get_default_promoted_type(arg_type);
8071                 if (!types_compatible(expected_type_skip, promoted_type) &&
8072                     !types_compatible(expected_type_skip, type_void_ptr) &&
8073                     !types_compatible(type_void_ptr,      promoted_type)) {
8074                         /* Deliberately show the skipped types in this warning */
8075                         warningf(&arg_expr->base.source_position,
8076                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
8077                                 pos, expected_type_skip, promoted_type);
8078                 }
8079         }
8080 }
8081
8082 /**
8083  * Parse a call expression, ie. expression '( ... )'.
8084  *
8085  * @param expression  the function address
8086  */
8087 static expression_t *parse_call_expression(expression_t *expression)
8088 {
8089         expression_t      *result = allocate_expression_zero(EXPR_CALL);
8090         call_expression_t *call   = &result->call;
8091         call->function            = expression;
8092
8093         type_t *const orig_type = expression->base.type;
8094         type_t *const type      = skip_typeref(orig_type);
8095
8096         function_type_t *function_type = NULL;
8097         if (is_type_pointer(type)) {
8098                 type_t *const to_type = skip_typeref(type->pointer.points_to);
8099
8100                 if (is_type_function(to_type)) {
8101                         function_type   = &to_type->function;
8102                         call->base.type = function_type->return_type;
8103                 }
8104         }
8105
8106         if (function_type == NULL && is_type_valid(type)) {
8107                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
8108         }
8109
8110         /* parse arguments */
8111         eat('(');
8112         add_anchor_token(')');
8113         add_anchor_token(',');
8114
8115         if (token.type != ')') {
8116                 call_argument_t *last_argument = NULL;
8117
8118                 while (true) {
8119                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
8120
8121                         argument->expression = parse_assignment_expression();
8122                         if (last_argument == NULL) {
8123                                 call->arguments = argument;
8124                         } else {
8125                                 last_argument->next = argument;
8126                         }
8127                         last_argument = argument;
8128
8129                         if (token.type != ',')
8130                                 break;
8131                         next_token();
8132                 }
8133         }
8134         rem_anchor_token(',');
8135         rem_anchor_token(')');
8136         expect(')', end_error);
8137
8138         if (function_type == NULL)
8139                 return result;
8140
8141         function_parameter_t *parameter = function_type->parameters;
8142         call_argument_t      *argument  = call->arguments;
8143         if (!function_type->unspecified_parameters) {
8144                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
8145                                 parameter = parameter->next, argument = argument->next) {
8146                         check_call_argument(parameter, argument, ++pos);
8147                 }
8148
8149                 if (parameter != NULL) {
8150                         errorf(HERE, "too few arguments to function '%E'", expression);
8151                 } else if (argument != NULL && !function_type->variadic) {
8152                         errorf(HERE, "too many arguments to function '%E'", expression);
8153                 }
8154         }
8155
8156         /* do default promotion */
8157         for (; argument != NULL; argument = argument->next) {
8158                 type_t *type = argument->expression->base.type;
8159
8160                 type = get_default_promoted_type(type);
8161
8162                 argument->expression
8163                         = create_implicit_cast(argument->expression, type);
8164         }
8165
8166         check_format(&result->call);
8167
8168         if (warning.aggregate_return &&
8169             is_type_compound(skip_typeref(function_type->return_type))) {
8170                 warningf(&result->base.source_position,
8171                          "function call has aggregate value");
8172         }
8173
8174 end_error:
8175         return result;
8176 }
8177
8178 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
8179
8180 static bool same_compound_type(const type_t *type1, const type_t *type2)
8181 {
8182         return
8183                 is_type_compound(type1) &&
8184                 type1->kind == type2->kind &&
8185                 type1->compound.compound == type2->compound.compound;
8186 }
8187
8188 static expression_t const *get_reference_address(expression_t const *expr)
8189 {
8190         bool regular_take_address = true;
8191         for (;;) {
8192                 if (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8193                         expr = expr->unary.value;
8194                 } else {
8195                         regular_take_address = false;
8196                 }
8197
8198                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8199                         break;
8200
8201                 expr = expr->unary.value;
8202         }
8203
8204         if (expr->kind != EXPR_REFERENCE)
8205                 return NULL;
8206
8207         /* special case for functions which are automatically converted to a
8208          * pointer to function without an extra TAKE_ADDRESS operation */
8209         if (!regular_take_address &&
8210                         expr->reference.entity->kind != ENTITY_FUNCTION) {
8211                 return NULL;
8212         }
8213
8214         return expr;
8215 }
8216
8217 static void warn_reference_address_as_bool(expression_t const* expr)
8218 {
8219         if (!warning.address)
8220                 return;
8221
8222         expr = get_reference_address(expr);
8223         if (expr != NULL) {
8224                 warningf(&expr->base.source_position,
8225                          "the address of '%Y' will always evaluate as 'true'",
8226                          expr->reference.entity->base.symbol);
8227         }
8228 }
8229
8230 static void warn_assignment_in_condition(const expression_t *const expr)
8231 {
8232         if (!warning.parentheses)
8233                 return;
8234         if (expr->base.kind != EXPR_BINARY_ASSIGN)
8235                 return;
8236         if (expr->base.parenthesized)
8237                 return;
8238         warningf(&expr->base.source_position,
8239                         "suggest parentheses around assignment used as truth value");
8240 }
8241
8242 static void semantic_condition(expression_t const *const expr,
8243                                char const *const context)
8244 {
8245         type_t *const type = skip_typeref(expr->base.type);
8246         if (is_type_scalar(type)) {
8247                 warn_reference_address_as_bool(expr);
8248                 warn_assignment_in_condition(expr);
8249         } else if (is_type_valid(type)) {
8250                 errorf(&expr->base.source_position,
8251                                 "%s must have scalar type", context);
8252         }
8253 }
8254
8255 /**
8256  * Parse a conditional expression, ie. 'expression ? ... : ...'.
8257  *
8258  * @param expression  the conditional expression
8259  */
8260 static expression_t *parse_conditional_expression(expression_t *expression)
8261 {
8262         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
8263
8264         conditional_expression_t *conditional = &result->conditional;
8265         conditional->condition                = expression;
8266
8267         eat('?');
8268         add_anchor_token(':');
8269
8270         /* §6.5.15:2  The first operand shall have scalar type. */
8271         semantic_condition(expression, "condition of conditional operator");
8272
8273         expression_t *true_expression = expression;
8274         bool          gnu_cond = false;
8275         if (GNU_MODE && token.type == ':') {
8276                 gnu_cond = true;
8277         } else {
8278                 true_expression = parse_expression();
8279         }
8280         rem_anchor_token(':');
8281         expect(':', end_error);
8282 end_error:;
8283         expression_t *false_expression =
8284                 parse_sub_expression(c_mode & _CXX ? PREC_ASSIGNMENT : PREC_CONDITIONAL);
8285
8286         type_t *const orig_true_type  = true_expression->base.type;
8287         type_t *const orig_false_type = false_expression->base.type;
8288         type_t *const true_type       = skip_typeref(orig_true_type);
8289         type_t *const false_type      = skip_typeref(orig_false_type);
8290
8291         /* 6.5.15.3 */
8292         type_t *result_type;
8293         if (is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8294                         is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
8295                 /* ISO/IEC 14882:1998(E) §5.16:2 */
8296                 if (true_expression->kind == EXPR_UNARY_THROW) {
8297                         result_type = false_type;
8298                 } else if (false_expression->kind == EXPR_UNARY_THROW) {
8299                         result_type = true_type;
8300                 } else {
8301                         if (warning.other && (
8302                                                 !is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8303                                                 !is_type_atomic(false_type, ATOMIC_TYPE_VOID)
8304                                         )) {
8305                                 warningf(&conditional->base.source_position,
8306                                                 "ISO C forbids conditional expression with only one void side");
8307                         }
8308                         result_type = type_void;
8309                 }
8310         } else if (is_type_arithmetic(true_type)
8311                    && is_type_arithmetic(false_type)) {
8312                 result_type = semantic_arithmetic(true_type, false_type);
8313
8314                 true_expression  = create_implicit_cast(true_expression, result_type);
8315                 false_expression = create_implicit_cast(false_expression, result_type);
8316
8317                 conditional->true_expression  = true_expression;
8318                 conditional->false_expression = false_expression;
8319                 conditional->base.type        = result_type;
8320         } else if (same_compound_type(true_type, false_type)) {
8321                 /* just take 1 of the 2 types */
8322                 result_type = true_type;
8323         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
8324                 type_t *pointer_type;
8325                 type_t *other_type;
8326                 expression_t *other_expression;
8327                 if (is_type_pointer(true_type) &&
8328                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
8329                         pointer_type     = true_type;
8330                         other_type       = false_type;
8331                         other_expression = false_expression;
8332                 } else {
8333                         pointer_type     = false_type;
8334                         other_type       = true_type;
8335                         other_expression = true_expression;
8336                 }
8337
8338                 if (is_null_pointer_constant(other_expression)) {
8339                         result_type = pointer_type;
8340                 } else if (is_type_pointer(other_type)) {
8341                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
8342                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
8343
8344                         type_t *to;
8345                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
8346                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
8347                                 to = type_void;
8348                         } else if (types_compatible(get_unqualified_type(to1),
8349                                                     get_unqualified_type(to2))) {
8350                                 to = to1;
8351                         } else {
8352                                 if (warning.other) {
8353                                         warningf(&conditional->base.source_position,
8354                                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
8355                                                         true_type, false_type);
8356                                 }
8357                                 to = type_void;
8358                         }
8359
8360                         type_t *const type =
8361                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
8362                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
8363                 } else if (is_type_integer(other_type)) {
8364                         if (warning.other) {
8365                                 warningf(&conditional->base.source_position,
8366                                                 "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
8367                         }
8368                         result_type = pointer_type;
8369                 } else {
8370                         if (is_type_valid(other_type)) {
8371                                 type_error_incompatible("while parsing conditional",
8372                                                 &expression->base.source_position, true_type, false_type);
8373                         }
8374                         result_type = type_error_type;
8375                 }
8376         } else {
8377                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
8378                         type_error_incompatible("while parsing conditional",
8379                                                 &conditional->base.source_position, true_type,
8380                                                 false_type);
8381                 }
8382                 result_type = type_error_type;
8383         }
8384
8385         conditional->true_expression
8386                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
8387         conditional->false_expression
8388                 = create_implicit_cast(false_expression, result_type);
8389         conditional->base.type = result_type;
8390         return result;
8391 }
8392
8393 /**
8394  * Parse an extension expression.
8395  */
8396 static expression_t *parse_extension(void)
8397 {
8398         eat(T___extension__);
8399
8400         bool old_gcc_extension   = in_gcc_extension;
8401         in_gcc_extension         = true;
8402         expression_t *expression = parse_sub_expression(PREC_UNARY);
8403         in_gcc_extension         = old_gcc_extension;
8404         return expression;
8405 }
8406
8407 /**
8408  * Parse a __builtin_classify_type() expression.
8409  */
8410 static expression_t *parse_builtin_classify_type(void)
8411 {
8412         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
8413         result->base.type    = type_int;
8414
8415         eat(T___builtin_classify_type);
8416
8417         expect('(', end_error);
8418         add_anchor_token(')');
8419         expression_t *expression = parse_expression();
8420         rem_anchor_token(')');
8421         expect(')', end_error);
8422         result->classify_type.type_expression = expression;
8423
8424         return result;
8425 end_error:
8426         return create_invalid_expression();
8427 }
8428
8429 /**
8430  * Parse a delete expression
8431  * ISO/IEC 14882:1998(E) §5.3.5
8432  */
8433 static expression_t *parse_delete(void)
8434 {
8435         expression_t *const result = allocate_expression_zero(EXPR_UNARY_DELETE);
8436         result->base.type          = type_void;
8437
8438         eat(T_delete);
8439
8440         if (token.type == '[') {
8441                 next_token();
8442                 result->kind = EXPR_UNARY_DELETE_ARRAY;
8443                 expect(']', end_error);
8444 end_error:;
8445         }
8446
8447         expression_t *const value = parse_sub_expression(PREC_CAST);
8448         result->unary.value = value;
8449
8450         type_t *const type = skip_typeref(value->base.type);
8451         if (!is_type_pointer(type)) {
8452                 if (is_type_valid(type)) {
8453                         errorf(&value->base.source_position,
8454                                         "operand of delete must have pointer type");
8455                 }
8456         } else if (warning.other &&
8457                         is_type_atomic(skip_typeref(type->pointer.points_to), ATOMIC_TYPE_VOID)) {
8458                 warningf(&value->base.source_position,
8459                                 "deleting 'void*' is undefined");
8460         }
8461
8462         return result;
8463 }
8464
8465 /**
8466  * Parse a throw expression
8467  * ISO/IEC 14882:1998(E) §15:1
8468  */
8469 static expression_t *parse_throw(void)
8470 {
8471         expression_t *const result = allocate_expression_zero(EXPR_UNARY_THROW);
8472         result->base.type          = type_void;
8473
8474         eat(T_throw);
8475
8476         expression_t *value = NULL;
8477         switch (token.type) {
8478                 EXPRESSION_START {
8479                         value = parse_assignment_expression();
8480                         /* ISO/IEC 14882:1998(E) §15.1:3 */
8481                         type_t *const orig_type = value->base.type;
8482                         type_t *const type      = skip_typeref(orig_type);
8483                         if (is_type_incomplete(type)) {
8484                                 errorf(&value->base.source_position,
8485                                                 "cannot throw object of incomplete type '%T'", orig_type);
8486                         } else if (is_type_pointer(type)) {
8487                                 type_t *const points_to = skip_typeref(type->pointer.points_to);
8488                                 if (is_type_incomplete(points_to) &&
8489                                                 !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8490                                         errorf(&value->base.source_position,
8491                                                         "cannot throw pointer to incomplete type '%T'", orig_type);
8492                                 }
8493                         }
8494                 }
8495
8496                 default:
8497                         break;
8498         }
8499         result->unary.value = value;
8500
8501         return result;
8502 }
8503
8504 static bool check_pointer_arithmetic(const source_position_t *source_position,
8505                                      type_t *pointer_type,
8506                                      type_t *orig_pointer_type)
8507 {
8508         type_t *points_to = pointer_type->pointer.points_to;
8509         points_to = skip_typeref(points_to);
8510
8511         if (is_type_incomplete(points_to)) {
8512                 if (!GNU_MODE || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8513                         errorf(source_position,
8514                                "arithmetic with pointer to incomplete type '%T' not allowed",
8515                                orig_pointer_type);
8516                         return false;
8517                 } else if (warning.pointer_arith) {
8518                         warningf(source_position,
8519                                  "pointer of type '%T' used in arithmetic",
8520                                  orig_pointer_type);
8521                 }
8522         } else if (is_type_function(points_to)) {
8523                 if (!GNU_MODE) {
8524                         errorf(source_position,
8525                                "arithmetic with pointer to function type '%T' not allowed",
8526                                orig_pointer_type);
8527                         return false;
8528                 } else if (warning.pointer_arith) {
8529                         warningf(source_position,
8530                                  "pointer to a function '%T' used in arithmetic",
8531                                  orig_pointer_type);
8532                 }
8533         }
8534         return true;
8535 }
8536
8537 static bool is_lvalue(const expression_t *expression)
8538 {
8539         /* TODO: doesn't seem to be consistent with §6.3.2.1 (1) */
8540         switch (expression->kind) {
8541         case EXPR_ARRAY_ACCESS:
8542         case EXPR_COMPOUND_LITERAL:
8543         case EXPR_REFERENCE:
8544         case EXPR_SELECT:
8545         case EXPR_UNARY_DEREFERENCE:
8546                 return true;
8547
8548         default: {
8549           type_t *type = skip_typeref(expression->base.type);
8550           return
8551                 /* ISO/IEC 14882:1998(E) §3.10:3 */
8552                 is_type_reference(type) ||
8553                 /* Claim it is an lvalue, if the type is invalid.  There was a parse
8554                  * error before, which maybe prevented properly recognizing it as
8555                  * lvalue. */
8556                 !is_type_valid(type);
8557         }
8558         }
8559 }
8560
8561 static void semantic_incdec(unary_expression_t *expression)
8562 {
8563         type_t *const orig_type = expression->value->base.type;
8564         type_t *const type      = skip_typeref(orig_type);
8565         if (is_type_pointer(type)) {
8566                 if (!check_pointer_arithmetic(&expression->base.source_position,
8567                                               type, orig_type)) {
8568                         return;
8569                 }
8570         } else if (!is_type_real(type) && is_type_valid(type)) {
8571                 /* TODO: improve error message */
8572                 errorf(&expression->base.source_position,
8573                        "operation needs an arithmetic or pointer type");
8574                 return;
8575         }
8576         if (!is_lvalue(expression->value)) {
8577                 /* TODO: improve error message */
8578                 errorf(&expression->base.source_position, "lvalue required as operand");
8579         }
8580         expression->base.type = orig_type;
8581 }
8582
8583 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
8584 {
8585         type_t *const orig_type = expression->value->base.type;
8586         type_t *const type      = skip_typeref(orig_type);
8587         if (!is_type_arithmetic(type)) {
8588                 if (is_type_valid(type)) {
8589                         /* TODO: improve error message */
8590                         errorf(&expression->base.source_position,
8591                                 "operation needs an arithmetic type");
8592                 }
8593                 return;
8594         }
8595
8596         expression->base.type = orig_type;
8597 }
8598
8599 static void semantic_unexpr_plus(unary_expression_t *expression)
8600 {
8601         semantic_unexpr_arithmetic(expression);
8602         if (warning.traditional)
8603                 warningf(&expression->base.source_position,
8604                         "traditional C rejects the unary plus operator");
8605 }
8606
8607 static void semantic_not(unary_expression_t *expression)
8608 {
8609         /* §6.5.3.3:1  The operand [...] of the ! operator, scalar type. */
8610         semantic_condition(expression->value, "operand of !");
8611         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8612 }
8613
8614 static void semantic_unexpr_integer(unary_expression_t *expression)
8615 {
8616         type_t *const orig_type = expression->value->base.type;
8617         type_t *const type      = skip_typeref(orig_type);
8618         if (!is_type_integer(type)) {
8619                 if (is_type_valid(type)) {
8620                         errorf(&expression->base.source_position,
8621                                "operand of ~ must be of integer type");
8622                 }
8623                 return;
8624         }
8625
8626         expression->base.type = orig_type;
8627 }
8628
8629 static void semantic_dereference(unary_expression_t *expression)
8630 {
8631         type_t *const orig_type = expression->value->base.type;
8632         type_t *const type      = skip_typeref(orig_type);
8633         if (!is_type_pointer(type)) {
8634                 if (is_type_valid(type)) {
8635                         errorf(&expression->base.source_position,
8636                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
8637                 }
8638                 return;
8639         }
8640
8641         type_t *result_type   = type->pointer.points_to;
8642         result_type           = automatic_type_conversion(result_type);
8643         expression->base.type = result_type;
8644 }
8645
8646 /**
8647  * Record that an address is taken (expression represents an lvalue).
8648  *
8649  * @param expression       the expression
8650  * @param may_be_register  if true, the expression might be an register
8651  */
8652 static void set_address_taken(expression_t *expression, bool may_be_register)
8653 {
8654         if (expression->kind != EXPR_REFERENCE)
8655                 return;
8656
8657         entity_t *const entity = expression->reference.entity;
8658
8659         if (entity->kind != ENTITY_VARIABLE && entity->kind != ENTITY_PARAMETER)
8660                 return;
8661
8662         if (entity->declaration.storage_class == STORAGE_CLASS_REGISTER
8663                         && !may_be_register) {
8664                 errorf(&expression->base.source_position,
8665                                 "address of register %s '%Y' requested",
8666                                 get_entity_kind_name(entity->kind),     entity->base.symbol);
8667         }
8668
8669         if (entity->kind == ENTITY_VARIABLE) {
8670                 entity->variable.address_taken = true;
8671         } else {
8672                 assert(entity->kind == ENTITY_PARAMETER);
8673                 entity->parameter.address_taken = true;
8674         }
8675 }
8676
8677 /**
8678  * Check the semantic of the address taken expression.
8679  */
8680 static void semantic_take_addr(unary_expression_t *expression)
8681 {
8682         expression_t *value = expression->value;
8683         value->base.type    = revert_automatic_type_conversion(value);
8684
8685         type_t *orig_type = value->base.type;
8686         type_t *type      = skip_typeref(orig_type);
8687         if (!is_type_valid(type))
8688                 return;
8689
8690         /* §6.5.3.2 */
8691         if (!is_lvalue(value)) {
8692                 errorf(&expression->base.source_position, "'&' requires an lvalue");
8693         }
8694         if (type->kind == TYPE_BITFIELD) {
8695                 errorf(&expression->base.source_position,
8696                        "'&' not allowed on object with bitfield type '%T'",
8697                        type);
8698         }
8699
8700         set_address_taken(value, false);
8701
8702         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
8703 }
8704
8705 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc) \
8706 static expression_t *parse_##unexpression_type(void)                         \
8707 {                                                                            \
8708         expression_t *unary_expression                                           \
8709                 = allocate_expression_zero(unexpression_type);                       \
8710         eat(token_type);                                                         \
8711         unary_expression->unary.value = parse_sub_expression(PREC_UNARY);        \
8712                                                                                  \
8713         sfunc(&unary_expression->unary);                                         \
8714                                                                                  \
8715         return unary_expression;                                                 \
8716 }
8717
8718 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
8719                                semantic_unexpr_arithmetic)
8720 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
8721                                semantic_unexpr_plus)
8722 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
8723                                semantic_not)
8724 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
8725                                semantic_dereference)
8726 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
8727                                semantic_take_addr)
8728 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
8729                                semantic_unexpr_integer)
8730 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
8731                                semantic_incdec)
8732 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
8733                                semantic_incdec)
8734
8735 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
8736                                                sfunc)                         \
8737 static expression_t *parse_##unexpression_type(expression_t *left)            \
8738 {                                                                             \
8739         expression_t *unary_expression                                            \
8740                 = allocate_expression_zero(unexpression_type);                        \
8741         eat(token_type);                                                          \
8742         unary_expression->unary.value = left;                                     \
8743                                                                                   \
8744         sfunc(&unary_expression->unary);                                          \
8745                                                                               \
8746         return unary_expression;                                                  \
8747 }
8748
8749 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
8750                                        EXPR_UNARY_POSTFIX_INCREMENT,
8751                                        semantic_incdec)
8752 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
8753                                        EXPR_UNARY_POSTFIX_DECREMENT,
8754                                        semantic_incdec)
8755
8756 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
8757 {
8758         /* TODO: handle complex + imaginary types */
8759
8760         type_left  = get_unqualified_type(type_left);
8761         type_right = get_unqualified_type(type_right);
8762
8763         /* § 6.3.1.8 Usual arithmetic conversions */
8764         if (type_left == type_long_double || type_right == type_long_double) {
8765                 return type_long_double;
8766         } else if (type_left == type_double || type_right == type_double) {
8767                 return type_double;
8768         } else if (type_left == type_float || type_right == type_float) {
8769                 return type_float;
8770         }
8771
8772         type_left  = promote_integer(type_left);
8773         type_right = promote_integer(type_right);
8774
8775         if (type_left == type_right)
8776                 return type_left;
8777
8778         bool const signed_left  = is_type_signed(type_left);
8779         bool const signed_right = is_type_signed(type_right);
8780         int const  rank_left    = get_rank(type_left);
8781         int const  rank_right   = get_rank(type_right);
8782
8783         if (signed_left == signed_right)
8784                 return rank_left >= rank_right ? type_left : type_right;
8785
8786         int     s_rank;
8787         int     u_rank;
8788         type_t *s_type;
8789         type_t *u_type;
8790         if (signed_left) {
8791                 s_rank = rank_left;
8792                 s_type = type_left;
8793                 u_rank = rank_right;
8794                 u_type = type_right;
8795         } else {
8796                 s_rank = rank_right;
8797                 s_type = type_right;
8798                 u_rank = rank_left;
8799                 u_type = type_left;
8800         }
8801
8802         if (u_rank >= s_rank)
8803                 return u_type;
8804
8805         /* casting rank to atomic_type_kind is a bit hacky, but makes things
8806          * easier here... */
8807         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
8808                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
8809                 return s_type;
8810
8811         switch (s_rank) {
8812                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
8813                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
8814                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
8815
8816                 default: panic("invalid atomic type");
8817         }
8818 }
8819
8820 /**
8821  * Check the semantic restrictions for a binary expression.
8822  */
8823 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
8824 {
8825         expression_t *const left            = expression->left;
8826         expression_t *const right           = expression->right;
8827         type_t       *const orig_type_left  = left->base.type;
8828         type_t       *const orig_type_right = right->base.type;
8829         type_t       *const type_left       = skip_typeref(orig_type_left);
8830         type_t       *const type_right      = skip_typeref(orig_type_right);
8831
8832         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8833                 /* TODO: improve error message */
8834                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8835                         errorf(&expression->base.source_position,
8836                                "operation needs arithmetic types");
8837                 }
8838                 return;
8839         }
8840
8841         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8842         expression->left      = create_implicit_cast(left, arithmetic_type);
8843         expression->right     = create_implicit_cast(right, arithmetic_type);
8844         expression->base.type = arithmetic_type;
8845 }
8846
8847 static void warn_div_by_zero(binary_expression_t const *const expression)
8848 {
8849         if (!warning.div_by_zero ||
8850             !is_type_integer(expression->base.type))
8851                 return;
8852
8853         expression_t const *const right = expression->right;
8854         /* The type of the right operand can be different for /= */
8855         if (is_type_integer(right->base.type) &&
8856             is_constant_expression(right)     &&
8857             fold_constant(right) == 0) {
8858                 warningf(&expression->base.source_position, "division by zero");
8859         }
8860 }
8861
8862 /**
8863  * Check the semantic restrictions for a div/mod expression.
8864  */
8865 static void semantic_divmod_arithmetic(binary_expression_t *expression) {
8866         semantic_binexpr_arithmetic(expression);
8867         warn_div_by_zero(expression);
8868 }
8869
8870 static void warn_addsub_in_shift(const expression_t *const expr)
8871 {
8872         if (expr->base.parenthesized)
8873                 return;
8874
8875         char op;
8876         switch (expr->kind) {
8877                 case EXPR_BINARY_ADD: op = '+'; break;
8878                 case EXPR_BINARY_SUB: op = '-'; break;
8879                 default:              return;
8880         }
8881
8882         warningf(&expr->base.source_position,
8883                         "suggest parentheses around '%c' inside shift", op);
8884 }
8885
8886 static void semantic_shift_op(binary_expression_t *expression)
8887 {
8888         expression_t *const left            = expression->left;
8889         expression_t *const right           = expression->right;
8890         type_t       *const orig_type_left  = left->base.type;
8891         type_t       *const orig_type_right = right->base.type;
8892         type_t       *      type_left       = skip_typeref(orig_type_left);
8893         type_t       *      type_right      = skip_typeref(orig_type_right);
8894
8895         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8896                 /* TODO: improve error message */
8897                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8898                         errorf(&expression->base.source_position,
8899                                "operands of shift operation must have integer types");
8900                 }
8901                 return;
8902         }
8903
8904         if (warning.parentheses) {
8905                 warn_addsub_in_shift(left);
8906                 warn_addsub_in_shift(right);
8907         }
8908
8909         type_left  = promote_integer(type_left);
8910         type_right = promote_integer(type_right);
8911
8912         expression->left      = create_implicit_cast(left, type_left);
8913         expression->right     = create_implicit_cast(right, type_right);
8914         expression->base.type = type_left;
8915 }
8916
8917 static void semantic_add(binary_expression_t *expression)
8918 {
8919         expression_t *const left            = expression->left;
8920         expression_t *const right           = expression->right;
8921         type_t       *const orig_type_left  = left->base.type;
8922         type_t       *const orig_type_right = right->base.type;
8923         type_t       *const type_left       = skip_typeref(orig_type_left);
8924         type_t       *const type_right      = skip_typeref(orig_type_right);
8925
8926         /* § 6.5.6 */
8927         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8928                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8929                 expression->left  = create_implicit_cast(left, arithmetic_type);
8930                 expression->right = create_implicit_cast(right, arithmetic_type);
8931                 expression->base.type = arithmetic_type;
8932         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8933                 check_pointer_arithmetic(&expression->base.source_position,
8934                                          type_left, orig_type_left);
8935                 expression->base.type = type_left;
8936         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
8937                 check_pointer_arithmetic(&expression->base.source_position,
8938                                          type_right, orig_type_right);
8939                 expression->base.type = type_right;
8940         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8941                 errorf(&expression->base.source_position,
8942                        "invalid operands to binary + ('%T', '%T')",
8943                        orig_type_left, orig_type_right);
8944         }
8945 }
8946
8947 static void semantic_sub(binary_expression_t *expression)
8948 {
8949         expression_t            *const left            = expression->left;
8950         expression_t            *const right           = expression->right;
8951         type_t                  *const orig_type_left  = left->base.type;
8952         type_t                  *const orig_type_right = right->base.type;
8953         type_t                  *const type_left       = skip_typeref(orig_type_left);
8954         type_t                  *const type_right      = skip_typeref(orig_type_right);
8955         source_position_t const *const pos             = &expression->base.source_position;
8956
8957         /* § 5.6.5 */
8958         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8959                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8960                 expression->left        = create_implicit_cast(left, arithmetic_type);
8961                 expression->right       = create_implicit_cast(right, arithmetic_type);
8962                 expression->base.type =  arithmetic_type;
8963         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8964                 check_pointer_arithmetic(&expression->base.source_position,
8965                                          type_left, orig_type_left);
8966                 expression->base.type = type_left;
8967         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8968                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
8969                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
8970                 if (!types_compatible(unqual_left, unqual_right)) {
8971                         errorf(pos,
8972                                "subtracting pointers to incompatible types '%T' and '%T'",
8973                                orig_type_left, orig_type_right);
8974                 } else if (!is_type_object(unqual_left)) {
8975                         if (!is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
8976                                 errorf(pos, "subtracting pointers to non-object types '%T'",
8977                                        orig_type_left);
8978                         } else if (warning.other) {
8979                                 warningf(pos, "subtracting pointers to void");
8980                         }
8981                 }
8982                 expression->base.type = type_ptrdiff_t;
8983         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8984                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
8985                        orig_type_left, orig_type_right);
8986         }
8987 }
8988
8989 static void warn_string_literal_address(expression_t const* expr)
8990 {
8991         while (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8992                 expr = expr->unary.value;
8993                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8994                         return;
8995                 expr = expr->unary.value;
8996         }
8997
8998         if (expr->kind == EXPR_STRING_LITERAL ||
8999             expr->kind == EXPR_WIDE_STRING_LITERAL) {
9000                 warningf(&expr->base.source_position,
9001                         "comparison with string literal results in unspecified behaviour");
9002         }
9003 }
9004
9005 static void warn_comparison_in_comparison(const expression_t *const expr)
9006 {
9007         if (expr->base.parenthesized)
9008                 return;
9009         switch (expr->base.kind) {
9010                 case EXPR_BINARY_LESS:
9011                 case EXPR_BINARY_GREATER:
9012                 case EXPR_BINARY_LESSEQUAL:
9013                 case EXPR_BINARY_GREATEREQUAL:
9014                 case EXPR_BINARY_NOTEQUAL:
9015                 case EXPR_BINARY_EQUAL:
9016                         warningf(&expr->base.source_position,
9017                                         "comparisons like 'x <= y < z' do not have their mathematical meaning");
9018                         break;
9019                 default:
9020                         break;
9021         }
9022 }
9023
9024 static bool maybe_negative(expression_t const *const expr)
9025 {
9026         return
9027                 !is_constant_expression(expr) ||
9028                 fold_constant(expr) < 0;
9029 }
9030
9031 /**
9032  * Check the semantics of comparison expressions.
9033  *
9034  * @param expression   The expression to check.
9035  */
9036 static void semantic_comparison(binary_expression_t *expression)
9037 {
9038         expression_t *left  = expression->left;
9039         expression_t *right = expression->right;
9040
9041         if (warning.address) {
9042                 warn_string_literal_address(left);
9043                 warn_string_literal_address(right);
9044
9045                 expression_t const* const func_left = get_reference_address(left);
9046                 if (func_left != NULL && is_null_pointer_constant(right)) {
9047                         warningf(&expression->base.source_position,
9048                                  "the address of '%Y' will never be NULL",
9049                                  func_left->reference.entity->base.symbol);
9050                 }
9051
9052                 expression_t const* const func_right = get_reference_address(right);
9053                 if (func_right != NULL && is_null_pointer_constant(right)) {
9054                         warningf(&expression->base.source_position,
9055                                  "the address of '%Y' will never be NULL",
9056                                  func_right->reference.entity->base.symbol);
9057                 }
9058         }
9059
9060         if (warning.parentheses) {
9061                 warn_comparison_in_comparison(left);
9062                 warn_comparison_in_comparison(right);
9063         }
9064
9065         type_t *orig_type_left  = left->base.type;
9066         type_t *orig_type_right = right->base.type;
9067         type_t *type_left       = skip_typeref(orig_type_left);
9068         type_t *type_right      = skip_typeref(orig_type_right);
9069
9070         /* TODO non-arithmetic types */
9071         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
9072                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
9073
9074                 /* test for signed vs unsigned compares */
9075                 if (warning.sign_compare && is_type_integer(arithmetic_type)) {
9076                         bool const signed_left  = is_type_signed(type_left);
9077                         bool const signed_right = is_type_signed(type_right);
9078                         if (signed_left != signed_right) {
9079                                 /* FIXME long long needs better const folding magic */
9080                                 /* TODO check whether constant value can be represented by other type */
9081                                 if ((signed_left  && maybe_negative(left)) ||
9082                                                 (signed_right && maybe_negative(right))) {
9083                                         warningf(&expression->base.source_position,
9084                                                         "comparison between signed and unsigned");
9085                                 }
9086                         }
9087                 }
9088
9089                 expression->left        = create_implicit_cast(left, arithmetic_type);
9090                 expression->right       = create_implicit_cast(right, arithmetic_type);
9091                 expression->base.type   = arithmetic_type;
9092                 if (warning.float_equal &&
9093                     (expression->base.kind == EXPR_BINARY_EQUAL ||
9094                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
9095                     is_type_float(arithmetic_type)) {
9096                         warningf(&expression->base.source_position,
9097                                  "comparing floating point with == or != is unsafe");
9098                 }
9099         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
9100                 /* TODO check compatibility */
9101         } else if (is_type_pointer(type_left)) {
9102                 expression->right = create_implicit_cast(right, type_left);
9103         } else if (is_type_pointer(type_right)) {
9104                 expression->left = create_implicit_cast(left, type_right);
9105         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9106                 type_error_incompatible("invalid operands in comparison",
9107                                         &expression->base.source_position,
9108                                         type_left, type_right);
9109         }
9110         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9111 }
9112
9113 /**
9114  * Checks if a compound type has constant fields.
9115  */
9116 static bool has_const_fields(const compound_type_t *type)
9117 {
9118         compound_t *compound = type->compound;
9119         entity_t   *entry    = compound->members.entities;
9120
9121         for (; entry != NULL; entry = entry->base.next) {
9122                 if (!is_declaration(entry))
9123                         continue;
9124
9125                 const type_t *decl_type = skip_typeref(entry->declaration.type);
9126                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
9127                         return true;
9128         }
9129
9130         return false;
9131 }
9132
9133 static bool is_valid_assignment_lhs(expression_t const* const left)
9134 {
9135         type_t *const orig_type_left = revert_automatic_type_conversion(left);
9136         type_t *const type_left      = skip_typeref(orig_type_left);
9137
9138         if (!is_lvalue(left)) {
9139                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
9140                        left);
9141                 return false;
9142         }
9143
9144         if (left->kind == EXPR_REFERENCE
9145                         && left->reference.entity->kind == ENTITY_FUNCTION) {
9146                 errorf(HERE, "cannot assign to function '%E'", left);
9147                 return false;
9148         }
9149
9150         if (is_type_array(type_left)) {
9151                 errorf(HERE, "cannot assign to array '%E'", left);
9152                 return false;
9153         }
9154         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
9155                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
9156                        orig_type_left);
9157                 return false;
9158         }
9159         if (is_type_incomplete(type_left)) {
9160                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
9161                        left, orig_type_left);
9162                 return false;
9163         }
9164         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
9165                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
9166                        left, orig_type_left);
9167                 return false;
9168         }
9169
9170         return true;
9171 }
9172
9173 static void semantic_arithmetic_assign(binary_expression_t *expression)
9174 {
9175         expression_t *left            = expression->left;
9176         expression_t *right           = expression->right;
9177         type_t       *orig_type_left  = left->base.type;
9178         type_t       *orig_type_right = right->base.type;
9179
9180         if (!is_valid_assignment_lhs(left))
9181                 return;
9182
9183         type_t *type_left  = skip_typeref(orig_type_left);
9184         type_t *type_right = skip_typeref(orig_type_right);
9185
9186         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
9187                 /* TODO: improve error message */
9188                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
9189                         errorf(&expression->base.source_position,
9190                                "operation needs arithmetic types");
9191                 }
9192                 return;
9193         }
9194
9195         /* combined instructions are tricky. We can't create an implicit cast on
9196          * the left side, because we need the uncasted form for the store.
9197          * The ast2firm pass has to know that left_type must be right_type
9198          * for the arithmetic operation and create a cast by itself */
9199         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
9200         expression->right       = create_implicit_cast(right, arithmetic_type);
9201         expression->base.type   = type_left;
9202 }
9203
9204 static void semantic_divmod_assign(binary_expression_t *expression)
9205 {
9206         semantic_arithmetic_assign(expression);
9207         warn_div_by_zero(expression);
9208 }
9209
9210 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
9211 {
9212         expression_t *const left            = expression->left;
9213         expression_t *const right           = expression->right;
9214         type_t       *const orig_type_left  = left->base.type;
9215         type_t       *const orig_type_right = right->base.type;
9216         type_t       *const type_left       = skip_typeref(orig_type_left);
9217         type_t       *const type_right      = skip_typeref(orig_type_right);
9218
9219         if (!is_valid_assignment_lhs(left))
9220                 return;
9221
9222         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
9223                 /* combined instructions are tricky. We can't create an implicit cast on
9224                  * the left side, because we need the uncasted form for the store.
9225                  * The ast2firm pass has to know that left_type must be right_type
9226                  * for the arithmetic operation and create a cast by itself */
9227                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
9228                 expression->right     = create_implicit_cast(right, arithmetic_type);
9229                 expression->base.type = type_left;
9230         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
9231                 check_pointer_arithmetic(&expression->base.source_position,
9232                                          type_left, orig_type_left);
9233                 expression->base.type = type_left;
9234         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9235                 errorf(&expression->base.source_position,
9236                        "incompatible types '%T' and '%T' in assignment",
9237                        orig_type_left, orig_type_right);
9238         }
9239 }
9240
9241 static void warn_logical_and_within_or(const expression_t *const expr)
9242 {
9243         if (expr->base.kind != EXPR_BINARY_LOGICAL_AND)
9244                 return;
9245         if (expr->base.parenthesized)
9246                 return;
9247         warningf(&expr->base.source_position,
9248                         "suggest parentheses around && within ||");
9249 }
9250
9251 /**
9252  * Check the semantic restrictions of a logical expression.
9253  */
9254 static void semantic_logical_op(binary_expression_t *expression)
9255 {
9256         /* §6.5.13:2  Each of the operands shall have scalar type.
9257          * §6.5.14:2  Each of the operands shall have scalar type. */
9258         semantic_condition(expression->left,   "left operand of logical operator");
9259         semantic_condition(expression->right, "right operand of logical operator");
9260         if (expression->base.kind == EXPR_BINARY_LOGICAL_OR &&
9261                         warning.parentheses) {
9262                 warn_logical_and_within_or(expression->left);
9263                 warn_logical_and_within_or(expression->right);
9264         }
9265         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9266 }
9267
9268 /**
9269  * Check the semantic restrictions of a binary assign expression.
9270  */
9271 static void semantic_binexpr_assign(binary_expression_t *expression)
9272 {
9273         expression_t *left           = expression->left;
9274         type_t       *orig_type_left = left->base.type;
9275
9276         if (!is_valid_assignment_lhs(left))
9277                 return;
9278
9279         assign_error_t error = semantic_assign(orig_type_left, expression->right);
9280         report_assign_error(error, orig_type_left, expression->right,
9281                         "assignment", &left->base.source_position);
9282         expression->right = create_implicit_cast(expression->right, orig_type_left);
9283         expression->base.type = orig_type_left;
9284 }
9285
9286 /**
9287  * Determine if the outermost operation (or parts thereof) of the given
9288  * expression has no effect in order to generate a warning about this fact.
9289  * Therefore in some cases this only examines some of the operands of the
9290  * expression (see comments in the function and examples below).
9291  * Examples:
9292  *   f() + 23;    // warning, because + has no effect
9293  *   x || f();    // no warning, because x controls execution of f()
9294  *   x ? y : f(); // warning, because y has no effect
9295  *   (void)x;     // no warning to be able to suppress the warning
9296  * This function can NOT be used for an "expression has definitely no effect"-
9297  * analysis. */
9298 static bool expression_has_effect(const expression_t *const expr)
9299 {
9300         switch (expr->kind) {
9301                 case EXPR_UNKNOWN:                   break;
9302                 case EXPR_INVALID:                   return true; /* do NOT warn */
9303                 case EXPR_REFERENCE:                 return false;
9304                 case EXPR_REFERENCE_ENUM_VALUE:      return false;
9305                 /* suppress the warning for microsoft __noop operations */
9306                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
9307                 case EXPR_CHARACTER_CONSTANT:        return false;
9308                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
9309                 case EXPR_STRING_LITERAL:            return false;
9310                 case EXPR_WIDE_STRING_LITERAL:       return false;
9311                 case EXPR_LABEL_ADDRESS:             return false;
9312
9313                 case EXPR_CALL: {
9314                         const call_expression_t *const call = &expr->call;
9315                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
9316                                 return true;
9317
9318                         switch (call->function->builtin_symbol.symbol->ID) {
9319                                 case T___builtin_va_end: return true;
9320                                 default:                 return false;
9321                         }
9322                 }
9323
9324                 /* Generate the warning if either the left or right hand side of a
9325                  * conditional expression has no effect */
9326                 case EXPR_CONDITIONAL: {
9327                         const conditional_expression_t *const cond = &expr->conditional;
9328                         return
9329                                 expression_has_effect(cond->true_expression) &&
9330                                 expression_has_effect(cond->false_expression);
9331                 }
9332
9333                 case EXPR_SELECT:                    return false;
9334                 case EXPR_ARRAY_ACCESS:              return false;
9335                 case EXPR_SIZEOF:                    return false;
9336                 case EXPR_CLASSIFY_TYPE:             return false;
9337                 case EXPR_ALIGNOF:                   return false;
9338
9339                 case EXPR_FUNCNAME:                  return false;
9340                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
9341                 case EXPR_BUILTIN_CONSTANT_P:        return false;
9342                 case EXPR_BUILTIN_PREFETCH:          return true;
9343                 case EXPR_OFFSETOF:                  return false;
9344                 case EXPR_VA_START:                  return true;
9345                 case EXPR_VA_ARG:                    return true;
9346                 case EXPR_STATEMENT:                 return true; // TODO
9347                 case EXPR_COMPOUND_LITERAL:          return false;
9348
9349                 case EXPR_UNARY_NEGATE:              return false;
9350                 case EXPR_UNARY_PLUS:                return false;
9351                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
9352                 case EXPR_UNARY_NOT:                 return false;
9353                 case EXPR_UNARY_DEREFERENCE:         return false;
9354                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
9355                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
9356                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
9357                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
9358                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
9359
9360                 /* Treat void casts as if they have an effect in order to being able to
9361                  * suppress the warning */
9362                 case EXPR_UNARY_CAST: {
9363                         type_t *const type = skip_typeref(expr->base.type);
9364                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
9365                 }
9366
9367                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
9368                 case EXPR_UNARY_ASSUME:              return true;
9369                 case EXPR_UNARY_DELETE:              return true;
9370                 case EXPR_UNARY_DELETE_ARRAY:        return true;
9371                 case EXPR_UNARY_THROW:               return true;
9372
9373                 case EXPR_BINARY_ADD:                return false;
9374                 case EXPR_BINARY_SUB:                return false;
9375                 case EXPR_BINARY_MUL:                return false;
9376                 case EXPR_BINARY_DIV:                return false;
9377                 case EXPR_BINARY_MOD:                return false;
9378                 case EXPR_BINARY_EQUAL:              return false;
9379                 case EXPR_BINARY_NOTEQUAL:           return false;
9380                 case EXPR_BINARY_LESS:               return false;
9381                 case EXPR_BINARY_LESSEQUAL:          return false;
9382                 case EXPR_BINARY_GREATER:            return false;
9383                 case EXPR_BINARY_GREATEREQUAL:       return false;
9384                 case EXPR_BINARY_BITWISE_AND:        return false;
9385                 case EXPR_BINARY_BITWISE_OR:         return false;
9386                 case EXPR_BINARY_BITWISE_XOR:        return false;
9387                 case EXPR_BINARY_SHIFTLEFT:          return false;
9388                 case EXPR_BINARY_SHIFTRIGHT:         return false;
9389                 case EXPR_BINARY_ASSIGN:             return true;
9390                 case EXPR_BINARY_MUL_ASSIGN:         return true;
9391                 case EXPR_BINARY_DIV_ASSIGN:         return true;
9392                 case EXPR_BINARY_MOD_ASSIGN:         return true;
9393                 case EXPR_BINARY_ADD_ASSIGN:         return true;
9394                 case EXPR_BINARY_SUB_ASSIGN:         return true;
9395                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
9396                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
9397                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
9398                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
9399                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
9400
9401                 /* Only examine the right hand side of && and ||, because the left hand
9402                  * side already has the effect of controlling the execution of the right
9403                  * hand side */
9404                 case EXPR_BINARY_LOGICAL_AND:
9405                 case EXPR_BINARY_LOGICAL_OR:
9406                 /* Only examine the right hand side of a comma expression, because the left
9407                  * hand side has a separate warning */
9408                 case EXPR_BINARY_COMMA:
9409                         return expression_has_effect(expr->binary.right);
9410
9411                 case EXPR_BINARY_ISGREATER:          return false;
9412                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
9413                 case EXPR_BINARY_ISLESS:             return false;
9414                 case EXPR_BINARY_ISLESSEQUAL:        return false;
9415                 case EXPR_BINARY_ISLESSGREATER:      return false;
9416                 case EXPR_BINARY_ISUNORDERED:        return false;
9417         }
9418
9419         internal_errorf(HERE, "unexpected expression");
9420 }
9421
9422 static void semantic_comma(binary_expression_t *expression)
9423 {
9424         if (warning.unused_value) {
9425                 const expression_t *const left = expression->left;
9426                 if (!expression_has_effect(left)) {
9427                         warningf(&left->base.source_position,
9428                                  "left-hand operand of comma expression has no effect");
9429                 }
9430         }
9431         expression->base.type = expression->right->base.type;
9432 }
9433
9434 /**
9435  * @param prec_r precedence of the right operand
9436  */
9437 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, prec_r, sfunc) \
9438 static expression_t *parse_##binexpression_type(expression_t *left)          \
9439 {                                                                            \
9440         expression_t *binexpr = allocate_expression_zero(binexpression_type);    \
9441         binexpr->binary.left  = left;                                            \
9442         eat(token_type);                                                         \
9443                                                                              \
9444         expression_t *right = parse_sub_expression(prec_r);                      \
9445                                                                              \
9446         binexpr->binary.right = right;                                           \
9447         sfunc(&binexpr->binary);                                                 \
9448                                                                              \
9449         return binexpr;                                                          \
9450 }
9451
9452 CREATE_BINEXPR_PARSER('*',                    EXPR_BINARY_MUL,                PREC_CAST,           semantic_binexpr_arithmetic)
9453 CREATE_BINEXPR_PARSER('/',                    EXPR_BINARY_DIV,                PREC_CAST,           semantic_divmod_arithmetic)
9454 CREATE_BINEXPR_PARSER('%',                    EXPR_BINARY_MOD,                PREC_CAST,           semantic_divmod_arithmetic)
9455 CREATE_BINEXPR_PARSER('+',                    EXPR_BINARY_ADD,                PREC_MULTIPLICATIVE, semantic_add)
9456 CREATE_BINEXPR_PARSER('-',                    EXPR_BINARY_SUB,                PREC_MULTIPLICATIVE, semantic_sub)
9457 CREATE_BINEXPR_PARSER(T_LESSLESS,             EXPR_BINARY_SHIFTLEFT,          PREC_ADDITIVE,       semantic_shift_op)
9458 CREATE_BINEXPR_PARSER(T_GREATERGREATER,       EXPR_BINARY_SHIFTRIGHT,         PREC_ADDITIVE,       semantic_shift_op)
9459 CREATE_BINEXPR_PARSER('<',                    EXPR_BINARY_LESS,               PREC_SHIFT,          semantic_comparison)
9460 CREATE_BINEXPR_PARSER('>',                    EXPR_BINARY_GREATER,            PREC_SHIFT,          semantic_comparison)
9461 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,          PREC_SHIFT,          semantic_comparison)
9462 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,       PREC_SHIFT,          semantic_comparison)
9463 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,           PREC_RELATIONAL,     semantic_comparison)
9464 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,              PREC_RELATIONAL,     semantic_comparison)
9465 CREATE_BINEXPR_PARSER('&',                    EXPR_BINARY_BITWISE_AND,        PREC_EQUALITY,       semantic_binexpr_arithmetic)
9466 CREATE_BINEXPR_PARSER('^',                    EXPR_BINARY_BITWISE_XOR,        PREC_AND,            semantic_binexpr_arithmetic)
9467 CREATE_BINEXPR_PARSER('|',                    EXPR_BINARY_BITWISE_OR,         PREC_XOR,            semantic_binexpr_arithmetic)
9468 CREATE_BINEXPR_PARSER(T_ANDAND,               EXPR_BINARY_LOGICAL_AND,        PREC_OR,             semantic_logical_op)
9469 CREATE_BINEXPR_PARSER(T_PIPEPIPE,             EXPR_BINARY_LOGICAL_OR,         PREC_LOGICAL_AND,    semantic_logical_op)
9470 CREATE_BINEXPR_PARSER('=',                    EXPR_BINARY_ASSIGN,             PREC_ASSIGNMENT,     semantic_binexpr_assign)
9471 CREATE_BINEXPR_PARSER(T_PLUSEQUAL,            EXPR_BINARY_ADD_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9472 CREATE_BINEXPR_PARSER(T_MINUSEQUAL,           EXPR_BINARY_SUB_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9473 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL,        EXPR_BINARY_MUL_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9474 CREATE_BINEXPR_PARSER(T_SLASHEQUAL,           EXPR_BINARY_DIV_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9475 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL,         EXPR_BINARY_MOD_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9476 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL,        EXPR_BINARY_SHIFTLEFT_ASSIGN,   PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9477 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL,  EXPR_BINARY_SHIFTRIGHT_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9478 CREATE_BINEXPR_PARSER(T_ANDEQUAL,             EXPR_BINARY_BITWISE_AND_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9479 CREATE_BINEXPR_PARSER(T_PIPEEQUAL,            EXPR_BINARY_BITWISE_OR_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9480 CREATE_BINEXPR_PARSER(T_CARETEQUAL,           EXPR_BINARY_BITWISE_XOR_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9481 CREATE_BINEXPR_PARSER(',',                    EXPR_BINARY_COMMA,              PREC_ASSIGNMENT,     semantic_comma)
9482
9483
9484 static expression_t *parse_sub_expression(precedence_t precedence)
9485 {
9486         if (token.type < 0) {
9487                 return expected_expression_error();
9488         }
9489
9490         expression_parser_function_t *parser
9491                 = &expression_parsers[token.type];
9492         source_position_t             source_position = token.source_position;
9493         expression_t                 *left;
9494
9495         if (parser->parser != NULL) {
9496                 left = parser->parser();
9497         } else {
9498                 left = parse_primary_expression();
9499         }
9500         assert(left != NULL);
9501         left->base.source_position = source_position;
9502
9503         while (true) {
9504                 if (token.type < 0) {
9505                         return expected_expression_error();
9506                 }
9507
9508                 parser = &expression_parsers[token.type];
9509                 if (parser->infix_parser == NULL)
9510                         break;
9511                 if (parser->infix_precedence < precedence)
9512                         break;
9513
9514                 left = parser->infix_parser(left);
9515
9516                 assert(left != NULL);
9517                 assert(left->kind != EXPR_UNKNOWN);
9518                 left->base.source_position = source_position;
9519         }
9520
9521         return left;
9522 }
9523
9524 /**
9525  * Parse an expression.
9526  */
9527 static expression_t *parse_expression(void)
9528 {
9529         return parse_sub_expression(PREC_EXPRESSION);
9530 }
9531
9532 /**
9533  * Register a parser for a prefix-like operator.
9534  *
9535  * @param parser      the parser function
9536  * @param token_type  the token type of the prefix token
9537  */
9538 static void register_expression_parser(parse_expression_function parser,
9539                                        int token_type)
9540 {
9541         expression_parser_function_t *entry = &expression_parsers[token_type];
9542
9543         if (entry->parser != NULL) {
9544                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9545                 panic("trying to register multiple expression parsers for a token");
9546         }
9547         entry->parser = parser;
9548 }
9549
9550 /**
9551  * Register a parser for an infix operator with given precedence.
9552  *
9553  * @param parser      the parser function
9554  * @param token_type  the token type of the infix operator
9555  * @param precedence  the precedence of the operator
9556  */
9557 static void register_infix_parser(parse_expression_infix_function parser,
9558                 int token_type, precedence_t precedence)
9559 {
9560         expression_parser_function_t *entry = &expression_parsers[token_type];
9561
9562         if (entry->infix_parser != NULL) {
9563                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9564                 panic("trying to register multiple infix expression parsers for a "
9565                       "token");
9566         }
9567         entry->infix_parser     = parser;
9568         entry->infix_precedence = precedence;
9569 }
9570
9571 /**
9572  * Initialize the expression parsers.
9573  */
9574 static void init_expression_parsers(void)
9575 {
9576         memset(&expression_parsers, 0, sizeof(expression_parsers));
9577
9578         register_infix_parser(parse_array_expression,               '[',                    PREC_POSTFIX);
9579         register_infix_parser(parse_call_expression,                '(',                    PREC_POSTFIX);
9580         register_infix_parser(parse_select_expression,              '.',                    PREC_POSTFIX);
9581         register_infix_parser(parse_select_expression,              T_MINUSGREATER,         PREC_POSTFIX);
9582         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,   T_PLUSPLUS,             PREC_POSTFIX);
9583         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,   T_MINUSMINUS,           PREC_POSTFIX);
9584         register_infix_parser(parse_EXPR_BINARY_MUL,                '*',                    PREC_MULTIPLICATIVE);
9585         register_infix_parser(parse_EXPR_BINARY_DIV,                '/',                    PREC_MULTIPLICATIVE);
9586         register_infix_parser(parse_EXPR_BINARY_MOD,                '%',                    PREC_MULTIPLICATIVE);
9587         register_infix_parser(parse_EXPR_BINARY_ADD,                '+',                    PREC_ADDITIVE);
9588         register_infix_parser(parse_EXPR_BINARY_SUB,                '-',                    PREC_ADDITIVE);
9589         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,          T_LESSLESS,             PREC_SHIFT);
9590         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,         T_GREATERGREATER,       PREC_SHIFT);
9591         register_infix_parser(parse_EXPR_BINARY_LESS,               '<',                    PREC_RELATIONAL);
9592         register_infix_parser(parse_EXPR_BINARY_GREATER,            '>',                    PREC_RELATIONAL);
9593         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,          T_LESSEQUAL,            PREC_RELATIONAL);
9594         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL,       T_GREATEREQUAL,         PREC_RELATIONAL);
9595         register_infix_parser(parse_EXPR_BINARY_EQUAL,              T_EQUALEQUAL,           PREC_EQUALITY);
9596         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,           T_EXCLAMATIONMARKEQUAL, PREC_EQUALITY);
9597         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,        '&',                    PREC_AND);
9598         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,        '^',                    PREC_XOR);
9599         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,         '|',                    PREC_OR);
9600         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,        T_ANDAND,               PREC_LOGICAL_AND);
9601         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,         T_PIPEPIPE,             PREC_LOGICAL_OR);
9602         register_infix_parser(parse_conditional_expression,         '?',                    PREC_CONDITIONAL);
9603         register_infix_parser(parse_EXPR_BINARY_ASSIGN,             '=',                    PREC_ASSIGNMENT);
9604         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,         T_PLUSEQUAL,            PREC_ASSIGNMENT);
9605         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,         T_MINUSEQUAL,           PREC_ASSIGNMENT);
9606         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,         T_ASTERISKEQUAL,        PREC_ASSIGNMENT);
9607         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,         T_SLASHEQUAL,           PREC_ASSIGNMENT);
9608         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,         T_PERCENTEQUAL,         PREC_ASSIGNMENT);
9609         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,   T_LESSLESSEQUAL,        PREC_ASSIGNMENT);
9610         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,  T_GREATERGREATEREQUAL,  PREC_ASSIGNMENT);
9611         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN, T_ANDEQUAL,             PREC_ASSIGNMENT);
9612         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,  T_PIPEEQUAL,            PREC_ASSIGNMENT);
9613         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN, T_CARETEQUAL,           PREC_ASSIGNMENT);
9614         register_infix_parser(parse_EXPR_BINARY_COMMA,              ',',                    PREC_EXPRESSION);
9615
9616         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-');
9617         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+');
9618         register_expression_parser(parse_EXPR_UNARY_NOT,              '!');
9619         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~');
9620         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*');
9621         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&');
9622         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT, T_PLUSPLUS);
9623         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT, T_MINUSMINUS);
9624         register_expression_parser(parse_sizeof,                      T_sizeof);
9625         register_expression_parser(parse_alignof,                     T___alignof__);
9626         register_expression_parser(parse_extension,                   T___extension__);
9627         register_expression_parser(parse_builtin_classify_type,       T___builtin_classify_type);
9628         register_expression_parser(parse_delete,                      T_delete);
9629         register_expression_parser(parse_throw,                       T_throw);
9630 }
9631
9632 /**
9633  * Parse a asm statement arguments specification.
9634  */
9635 static asm_argument_t *parse_asm_arguments(bool is_out)
9636 {
9637         asm_argument_t  *result = NULL;
9638         asm_argument_t **anchor = &result;
9639
9640         while (token.type == T_STRING_LITERAL || token.type == '[') {
9641                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
9642                 memset(argument, 0, sizeof(argument[0]));
9643
9644                 if (token.type == '[') {
9645                         eat('[');
9646                         if (token.type != T_IDENTIFIER) {
9647                                 parse_error_expected("while parsing asm argument",
9648                                                      T_IDENTIFIER, NULL);
9649                                 return NULL;
9650                         }
9651                         argument->symbol = token.v.symbol;
9652
9653                         expect(']', end_error);
9654                 }
9655
9656                 argument->constraints = parse_string_literals();
9657                 expect('(', end_error);
9658                 add_anchor_token(')');
9659                 expression_t *expression = parse_expression();
9660                 rem_anchor_token(')');
9661                 if (is_out) {
9662                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
9663                          * change size or type representation (e.g. int -> long is ok, but
9664                          * int -> float is not) */
9665                         if (expression->kind == EXPR_UNARY_CAST) {
9666                                 type_t      *const type = expression->base.type;
9667                                 type_kind_t  const kind = type->kind;
9668                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
9669                                         unsigned flags;
9670                                         unsigned size;
9671                                         if (kind == TYPE_ATOMIC) {
9672                                                 atomic_type_kind_t const akind = type->atomic.akind;
9673                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9674                                                 size  = get_atomic_type_size(akind);
9675                                         } else {
9676                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9677                                                 size  = get_atomic_type_size(get_intptr_kind());
9678                                         }
9679
9680                                         do {
9681                                                 expression_t *const value      = expression->unary.value;
9682                                                 type_t       *const value_type = value->base.type;
9683                                                 type_kind_t   const value_kind = value_type->kind;
9684
9685                                                 unsigned value_flags;
9686                                                 unsigned value_size;
9687                                                 if (value_kind == TYPE_ATOMIC) {
9688                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
9689                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9690                                                         value_size  = get_atomic_type_size(value_akind);
9691                                                 } else if (value_kind == TYPE_POINTER) {
9692                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9693                                                         value_size  = get_atomic_type_size(get_intptr_kind());
9694                                                 } else {
9695                                                         break;
9696                                                 }
9697
9698                                                 if (value_flags != flags || value_size != size)
9699                                                         break;
9700
9701                                                 expression = value;
9702                                         } while (expression->kind == EXPR_UNARY_CAST);
9703                                 }
9704                         }
9705
9706                         if (!is_lvalue(expression)) {
9707                                 errorf(&expression->base.source_position,
9708                                        "asm output argument is not an lvalue");
9709                         }
9710
9711                         if (argument->constraints.begin[0] == '+')
9712                                 mark_vars_read(expression, NULL);
9713                 } else {
9714                         mark_vars_read(expression, NULL);
9715                 }
9716                 argument->expression = expression;
9717                 expect(')', end_error);
9718
9719                 set_address_taken(expression, true);
9720
9721                 *anchor = argument;
9722                 anchor  = &argument->next;
9723
9724                 if (token.type != ',')
9725                         break;
9726                 eat(',');
9727         }
9728
9729         return result;
9730 end_error:
9731         return NULL;
9732 }
9733
9734 /**
9735  * Parse a asm statement clobber specification.
9736  */
9737 static asm_clobber_t *parse_asm_clobbers(void)
9738 {
9739         asm_clobber_t *result = NULL;
9740         asm_clobber_t *last   = NULL;
9741
9742         while (token.type == T_STRING_LITERAL) {
9743                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
9744                 clobber->clobber       = parse_string_literals();
9745
9746                 if (last != NULL) {
9747                         last->next = clobber;
9748                 } else {
9749                         result = clobber;
9750                 }
9751                 last = clobber;
9752
9753                 if (token.type != ',')
9754                         break;
9755                 eat(',');
9756         }
9757
9758         return result;
9759 }
9760
9761 /**
9762  * Parse an asm statement.
9763  */
9764 static statement_t *parse_asm_statement(void)
9765 {
9766         statement_t     *statement     = allocate_statement_zero(STATEMENT_ASM);
9767         asm_statement_t *asm_statement = &statement->asms;
9768
9769         eat(T_asm);
9770
9771         if (token.type == T_volatile) {
9772                 next_token();
9773                 asm_statement->is_volatile = true;
9774         }
9775
9776         expect('(', end_error);
9777         add_anchor_token(')');
9778         add_anchor_token(':');
9779         asm_statement->asm_text = parse_string_literals();
9780
9781         if (token.type != ':') {
9782                 rem_anchor_token(':');
9783                 goto end_of_asm;
9784         }
9785         eat(':');
9786
9787         asm_statement->outputs = parse_asm_arguments(true);
9788         if (token.type != ':') {
9789                 rem_anchor_token(':');
9790                 goto end_of_asm;
9791         }
9792         eat(':');
9793
9794         asm_statement->inputs = parse_asm_arguments(false);
9795         if (token.type != ':') {
9796                 rem_anchor_token(':');
9797                 goto end_of_asm;
9798         }
9799         rem_anchor_token(':');
9800         eat(':');
9801
9802         asm_statement->clobbers = parse_asm_clobbers();
9803
9804 end_of_asm:
9805         rem_anchor_token(')');
9806         expect(')', end_error);
9807         expect(';', end_error);
9808
9809         if (asm_statement->outputs == NULL) {
9810                 /* GCC: An 'asm' instruction without any output operands will be treated
9811                  * identically to a volatile 'asm' instruction. */
9812                 asm_statement->is_volatile = true;
9813         }
9814
9815         return statement;
9816 end_error:
9817         return create_invalid_statement();
9818 }
9819
9820 /**
9821  * Parse a case statement.
9822  */
9823 static statement_t *parse_case_statement(void)
9824 {
9825         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9826         source_position_t *const pos       = &statement->base.source_position;
9827
9828         eat(T_case);
9829
9830         expression_t *const expression   = parse_expression();
9831         statement->case_label.expression = expression;
9832         if (!is_constant_expression(expression)) {
9833                 /* This check does not prevent the error message in all cases of an
9834                  * prior error while parsing the expression.  At least it catches the
9835                  * common case of a mistyped enum entry. */
9836                 if (is_type_valid(skip_typeref(expression->base.type))) {
9837                         errorf(pos, "case label does not reduce to an integer constant");
9838                 }
9839                 statement->case_label.is_bad = true;
9840         } else {
9841                 long const val = fold_constant(expression);
9842                 statement->case_label.first_case = val;
9843                 statement->case_label.last_case  = val;
9844         }
9845
9846         if (GNU_MODE) {
9847                 if (token.type == T_DOTDOTDOT) {
9848                         next_token();
9849                         expression_t *const end_range   = parse_expression();
9850                         statement->case_label.end_range = end_range;
9851                         if (!is_constant_expression(end_range)) {
9852                                 /* This check does not prevent the error message in all cases of an
9853                                  * prior error while parsing the expression.  At least it catches the
9854                                  * common case of a mistyped enum entry. */
9855                                 if (is_type_valid(skip_typeref(end_range->base.type))) {
9856                                         errorf(pos, "case range does not reduce to an integer constant");
9857                                 }
9858                                 statement->case_label.is_bad = true;
9859                         } else {
9860                                 long const val = fold_constant(end_range);
9861                                 statement->case_label.last_case = val;
9862
9863                                 if (warning.other && val < statement->case_label.first_case) {
9864                                         statement->case_label.is_empty_range = true;
9865                                         warningf(pos, "empty range specified");
9866                                 }
9867                         }
9868                 }
9869         }
9870
9871         PUSH_PARENT(statement);
9872
9873         expect(':', end_error);
9874 end_error:
9875
9876         if (current_switch != NULL) {
9877                 if (! statement->case_label.is_bad) {
9878                         /* Check for duplicate case values */
9879                         case_label_statement_t *c = &statement->case_label;
9880                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
9881                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
9882                                         continue;
9883
9884                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
9885                                         continue;
9886
9887                                 errorf(pos, "duplicate case value (previously used %P)",
9888                                        &l->base.source_position);
9889                                 break;
9890                         }
9891                 }
9892                 /* link all cases into the switch statement */
9893                 if (current_switch->last_case == NULL) {
9894                         current_switch->first_case      = &statement->case_label;
9895                 } else {
9896                         current_switch->last_case->next = &statement->case_label;
9897                 }
9898                 current_switch->last_case = &statement->case_label;
9899         } else {
9900                 errorf(pos, "case label not within a switch statement");
9901         }
9902
9903         statement_t *const inner_stmt = parse_statement();
9904         statement->case_label.statement = inner_stmt;
9905         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9906                 errorf(&inner_stmt->base.source_position, "declaration after case label");
9907         }
9908
9909         POP_PARENT;
9910         return statement;
9911 }
9912
9913 /**
9914  * Parse a default statement.
9915  */
9916 static statement_t *parse_default_statement(void)
9917 {
9918         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9919
9920         eat(T_default);
9921
9922         PUSH_PARENT(statement);
9923
9924         expect(':', end_error);
9925         if (current_switch != NULL) {
9926                 const case_label_statement_t *def_label = current_switch->default_label;
9927                 if (def_label != NULL) {
9928                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
9929                                &def_label->base.source_position);
9930                 } else {
9931                         current_switch->default_label = &statement->case_label;
9932
9933                         /* link all cases into the switch statement */
9934                         if (current_switch->last_case == NULL) {
9935                                 current_switch->first_case      = &statement->case_label;
9936                         } else {
9937                                 current_switch->last_case->next = &statement->case_label;
9938                         }
9939                         current_switch->last_case = &statement->case_label;
9940                 }
9941         } else {
9942                 errorf(&statement->base.source_position,
9943                         "'default' label not within a switch statement");
9944         }
9945
9946         statement_t *const inner_stmt = parse_statement();
9947         statement->case_label.statement = inner_stmt;
9948         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9949                 errorf(&inner_stmt->base.source_position, "declaration after default label");
9950         }
9951
9952         POP_PARENT;
9953         return statement;
9954 end_error:
9955         POP_PARENT;
9956         return create_invalid_statement();
9957 }
9958
9959 /**
9960  * Parse a label statement.
9961  */
9962 static statement_t *parse_label_statement(void)
9963 {
9964         assert(token.type == T_IDENTIFIER);
9965         symbol_t *symbol = token.v.symbol;
9966         label_t  *label  = get_label(symbol);
9967
9968         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
9969         statement->label.label       = label;
9970
9971         next_token();
9972
9973         PUSH_PARENT(statement);
9974
9975         /* if statement is already set then the label is defined twice,
9976          * otherwise it was just mentioned in a goto/local label declaration so far
9977          */
9978         if (label->statement != NULL) {
9979                 errorf(HERE, "duplicate label '%Y' (declared %P)",
9980                        symbol, &label->base.source_position);
9981         } else {
9982                 label->base.source_position = token.source_position;
9983                 label->statement            = statement;
9984         }
9985
9986         eat(':');
9987
9988         if (token.type == '}') {
9989                 /* TODO only warn? */
9990                 if (warning.other && false) {
9991                         warningf(HERE, "label at end of compound statement");
9992                         statement->label.statement = create_empty_statement();
9993                 } else {
9994                         errorf(HERE, "label at end of compound statement");
9995                         statement->label.statement = create_invalid_statement();
9996                 }
9997         } else if (token.type == ';') {
9998                 /* Eat an empty statement here, to avoid the warning about an empty
9999                  * statement after a label.  label:; is commonly used to have a label
10000                  * before a closing brace. */
10001                 statement->label.statement = create_empty_statement();
10002                 next_token();
10003         } else {
10004                 statement_t *const inner_stmt = parse_statement();
10005                 statement->label.statement = inner_stmt;
10006                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
10007                         errorf(&inner_stmt->base.source_position, "declaration after label");
10008                 }
10009         }
10010
10011         /* remember the labels in a list for later checking */
10012         *label_anchor = &statement->label;
10013         label_anchor  = &statement->label.next;
10014
10015         POP_PARENT;
10016         return statement;
10017 }
10018
10019 /**
10020  * Parse an if statement.
10021  */
10022 static statement_t *parse_if(void)
10023 {
10024         statement_t *statement = allocate_statement_zero(STATEMENT_IF);
10025
10026         eat(T_if);
10027
10028         PUSH_PARENT(statement);
10029
10030         add_anchor_token('{');
10031
10032         expect('(', end_error);
10033         add_anchor_token(')');
10034         expression_t *const expr = parse_expression();
10035         statement->ifs.condition = expr;
10036         /* §6.8.4.1:1  The controlling expression of an if statement shall have
10037          *             scalar type. */
10038         semantic_condition(expr, "condition of 'if'-statment");
10039         mark_vars_read(expr, NULL);
10040         rem_anchor_token(')');
10041         expect(')', end_error);
10042
10043 end_error:
10044         rem_anchor_token('{');
10045
10046         add_anchor_token(T_else);
10047         statement_t *const true_stmt = parse_statement();
10048         statement->ifs.true_statement = true_stmt;
10049         rem_anchor_token(T_else);
10050
10051         if (token.type == T_else) {
10052                 next_token();
10053                 statement->ifs.false_statement = parse_statement();
10054         } else if (warning.parentheses &&
10055                         true_stmt->kind == STATEMENT_IF &&
10056                         true_stmt->ifs.false_statement != NULL) {
10057                 warningf(&true_stmt->base.source_position,
10058                                 "suggest explicit braces to avoid ambiguous 'else'");
10059         }
10060
10061         POP_PARENT;
10062         return statement;
10063 }
10064
10065 /**
10066  * Check that all enums are handled in a switch.
10067  *
10068  * @param statement  the switch statement to check
10069  */
10070 static void check_enum_cases(const switch_statement_t *statement) {
10071         const type_t *type = skip_typeref(statement->expression->base.type);
10072         if (! is_type_enum(type))
10073                 return;
10074         const enum_type_t *enumt = &type->enumt;
10075
10076         /* if we have a default, no warnings */
10077         if (statement->default_label != NULL)
10078                 return;
10079
10080         /* FIXME: calculation of value should be done while parsing */
10081         /* TODO: quadratic algorithm here. Change to an n log n one */
10082         long            last_value = -1;
10083         const entity_t *entry      = enumt->enume->base.next;
10084         for (; entry != NULL && entry->kind == ENTITY_ENUM_VALUE;
10085              entry = entry->base.next) {
10086                 const expression_t *expression = entry->enum_value.value;
10087                 long                value      = expression != NULL ? fold_constant(expression) : last_value + 1;
10088                 bool                found      = false;
10089                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
10090                         if (l->expression == NULL)
10091                                 continue;
10092                         if (l->first_case <= value && value <= l->last_case) {
10093                                 found = true;
10094                                 break;
10095                         }
10096                 }
10097                 if (! found) {
10098                         warningf(&statement->base.source_position,
10099                                  "enumeration value '%Y' not handled in switch",
10100                                  entry->base.symbol);
10101                 }
10102                 last_value = value;
10103         }
10104 }
10105
10106 /**
10107  * Parse a switch statement.
10108  */
10109 static statement_t *parse_switch(void)
10110 {
10111         statement_t *statement = allocate_statement_zero(STATEMENT_SWITCH);
10112
10113         eat(T_switch);
10114
10115         PUSH_PARENT(statement);
10116
10117         expect('(', end_error);
10118         add_anchor_token(')');
10119         expression_t *const expr = parse_expression();
10120         mark_vars_read(expr, NULL);
10121         type_t       *      type = skip_typeref(expr->base.type);
10122         if (is_type_integer(type)) {
10123                 type = promote_integer(type);
10124                 if (warning.traditional) {
10125                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
10126                                 warningf(&expr->base.source_position,
10127                                         "'%T' switch expression not converted to '%T' in ISO C",
10128                                         type, type_int);
10129                         }
10130                 }
10131         } else if (is_type_valid(type)) {
10132                 errorf(&expr->base.source_position,
10133                        "switch quantity is not an integer, but '%T'", type);
10134                 type = type_error_type;
10135         }
10136         statement->switchs.expression = create_implicit_cast(expr, type);
10137         expect(')', end_error);
10138         rem_anchor_token(')');
10139
10140         switch_statement_t *rem = current_switch;
10141         current_switch          = &statement->switchs;
10142         statement->switchs.body = parse_statement();
10143         current_switch          = rem;
10144
10145         if (warning.switch_default &&
10146             statement->switchs.default_label == NULL) {
10147                 warningf(&statement->base.source_position, "switch has no default case");
10148         }
10149         if (warning.switch_enum)
10150                 check_enum_cases(&statement->switchs);
10151
10152         POP_PARENT;
10153         return statement;
10154 end_error:
10155         POP_PARENT;
10156         return create_invalid_statement();
10157 }
10158
10159 static statement_t *parse_loop_body(statement_t *const loop)
10160 {
10161         statement_t *const rem = current_loop;
10162         current_loop = loop;
10163
10164         statement_t *const body = parse_statement();
10165
10166         current_loop = rem;
10167         return body;
10168 }
10169
10170 /**
10171  * Parse a while statement.
10172  */
10173 static statement_t *parse_while(void)
10174 {
10175         statement_t *statement = allocate_statement_zero(STATEMENT_WHILE);
10176
10177         eat(T_while);
10178
10179         PUSH_PARENT(statement);
10180
10181         expect('(', end_error);
10182         add_anchor_token(')');
10183         expression_t *const cond = parse_expression();
10184         statement->whiles.condition = cond;
10185         /* §6.8.5:2    The controlling expression of an iteration statement shall
10186          *             have scalar type. */
10187         semantic_condition(cond, "condition of 'while'-statement");
10188         mark_vars_read(cond, NULL);
10189         rem_anchor_token(')');
10190         expect(')', end_error);
10191
10192         statement->whiles.body = parse_loop_body(statement);
10193
10194         POP_PARENT;
10195         return statement;
10196 end_error:
10197         POP_PARENT;
10198         return create_invalid_statement();
10199 }
10200
10201 /**
10202  * Parse a do statement.
10203  */
10204 static statement_t *parse_do(void)
10205 {
10206         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
10207
10208         eat(T_do);
10209
10210         PUSH_PARENT(statement);
10211
10212         add_anchor_token(T_while);
10213         statement->do_while.body = parse_loop_body(statement);
10214         rem_anchor_token(T_while);
10215
10216         expect(T_while, end_error);
10217         expect('(', end_error);
10218         add_anchor_token(')');
10219         expression_t *const cond = parse_expression();
10220         statement->do_while.condition = cond;
10221         /* §6.8.5:2    The controlling expression of an iteration statement shall
10222          *             have scalar type. */
10223         semantic_condition(cond, "condition of 'do-while'-statement");
10224         mark_vars_read(cond, NULL);
10225         rem_anchor_token(')');
10226         expect(')', end_error);
10227         expect(';', end_error);
10228
10229         POP_PARENT;
10230         return statement;
10231 end_error:
10232         POP_PARENT;
10233         return create_invalid_statement();
10234 }
10235
10236 /**
10237  * Parse a for statement.
10238  */
10239 static statement_t *parse_for(void)
10240 {
10241         statement_t *statement = allocate_statement_zero(STATEMENT_FOR);
10242
10243         eat(T_for);
10244
10245         expect('(', end_error1);
10246         add_anchor_token(')');
10247
10248         PUSH_PARENT(statement);
10249
10250         size_t const  top       = environment_top();
10251         scope_t      *old_scope = scope_push(&statement->fors.scope);
10252
10253         if (token.type == ';') {
10254                 next_token();
10255         } else if (is_declaration_specifier(&token, false)) {
10256                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10257         } else {
10258                 add_anchor_token(';');
10259                 expression_t *const init = parse_expression();
10260                 statement->fors.initialisation = init;
10261                 mark_vars_read(init, ENT_ANY);
10262                 if (warning.unused_value && !expression_has_effect(init)) {
10263                         warningf(&init->base.source_position,
10264                                         "initialisation of 'for'-statement has no effect");
10265                 }
10266                 rem_anchor_token(';');
10267                 expect(';', end_error2);
10268         }
10269
10270         if (token.type != ';') {
10271                 add_anchor_token(';');
10272                 expression_t *const cond = parse_expression();
10273                 statement->fors.condition = cond;
10274                 /* §6.8.5:2    The controlling expression of an iteration statement
10275                  *             shall have scalar type. */
10276                 semantic_condition(cond, "condition of 'for'-statement");
10277                 mark_vars_read(cond, NULL);
10278                 rem_anchor_token(';');
10279         }
10280         expect(';', end_error2);
10281         if (token.type != ')') {
10282                 expression_t *const step = parse_expression();
10283                 statement->fors.step = step;
10284                 mark_vars_read(step, ENT_ANY);
10285                 if (warning.unused_value && !expression_has_effect(step)) {
10286                         warningf(&step->base.source_position,
10287                                  "step of 'for'-statement has no effect");
10288                 }
10289         }
10290         expect(')', end_error2);
10291         rem_anchor_token(')');
10292         statement->fors.body = parse_loop_body(statement);
10293
10294         assert(current_scope == &statement->fors.scope);
10295         scope_pop(old_scope);
10296         environment_pop_to(top);
10297
10298         POP_PARENT;
10299         return statement;
10300
10301 end_error2:
10302         POP_PARENT;
10303         rem_anchor_token(')');
10304         assert(current_scope == &statement->fors.scope);
10305         scope_pop(old_scope);
10306         environment_pop_to(top);
10307         /* fallthrough */
10308
10309 end_error1:
10310         return create_invalid_statement();
10311 }
10312
10313 /**
10314  * Parse a goto statement.
10315  */
10316 static statement_t *parse_goto(void)
10317 {
10318         statement_t *statement = allocate_statement_zero(STATEMENT_GOTO);
10319         eat(T_goto);
10320
10321         if (GNU_MODE && token.type == '*') {
10322                 next_token();
10323                 expression_t *expression = parse_expression();
10324                 mark_vars_read(expression, NULL);
10325
10326                 /* Argh: although documentation says the expression must be of type void*,
10327                  * gcc accepts anything that can be casted into void* without error */
10328                 type_t *type = expression->base.type;
10329
10330                 if (type != type_error_type) {
10331                         if (!is_type_pointer(type) && !is_type_integer(type)) {
10332                                 errorf(&expression->base.source_position,
10333                                         "cannot convert to a pointer type");
10334                         } else if (warning.other && type != type_void_ptr) {
10335                                 warningf(&expression->base.source_position,
10336                                         "type of computed goto expression should be 'void*' not '%T'", type);
10337                         }
10338                         expression = create_implicit_cast(expression, type_void_ptr);
10339                 }
10340
10341                 statement->gotos.expression = expression;
10342         } else {
10343                 if (token.type != T_IDENTIFIER) {
10344                         if (GNU_MODE)
10345                                 parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
10346                         else
10347                                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
10348                         eat_until_anchor();
10349                         goto end_error;
10350                 }
10351                 symbol_t *symbol = token.v.symbol;
10352                 next_token();
10353
10354                 statement->gotos.label = get_label(symbol);
10355         }
10356
10357         /* remember the goto's in a list for later checking */
10358         *goto_anchor = &statement->gotos;
10359         goto_anchor  = &statement->gotos.next;
10360
10361         expect(';', end_error);
10362
10363         return statement;
10364 end_error:
10365         return create_invalid_statement();
10366 }
10367
10368 /**
10369  * Parse a continue statement.
10370  */
10371 static statement_t *parse_continue(void)
10372 {
10373         if (current_loop == NULL) {
10374                 errorf(HERE, "continue statement not within loop");
10375         }
10376
10377         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
10378
10379         eat(T_continue);
10380         expect(';', end_error);
10381
10382 end_error:
10383         return statement;
10384 }
10385
10386 /**
10387  * Parse a break statement.
10388  */
10389 static statement_t *parse_break(void)
10390 {
10391         if (current_switch == NULL && current_loop == NULL) {
10392                 errorf(HERE, "break statement not within loop or switch");
10393         }
10394
10395         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
10396
10397         eat(T_break);
10398         expect(';', end_error);
10399
10400 end_error:
10401         return statement;
10402 }
10403
10404 /**
10405  * Parse a __leave statement.
10406  */
10407 static statement_t *parse_leave_statement(void)
10408 {
10409         if (current_try == NULL) {
10410                 errorf(HERE, "__leave statement not within __try");
10411         }
10412
10413         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
10414
10415         eat(T___leave);
10416         expect(';', end_error);
10417
10418 end_error:
10419         return statement;
10420 }
10421
10422 /**
10423  * Check if a given entity represents a local variable.
10424  */
10425 static bool is_local_variable(const entity_t *entity)
10426 {
10427         if (entity->kind != ENTITY_VARIABLE)
10428                 return false;
10429
10430         switch ((storage_class_tag_t) entity->declaration.storage_class) {
10431         case STORAGE_CLASS_AUTO:
10432         case STORAGE_CLASS_REGISTER: {
10433                 const type_t *type = skip_typeref(entity->declaration.type);
10434                 if (is_type_function(type)) {
10435                         return false;
10436                 } else {
10437                         return true;
10438                 }
10439         }
10440         default:
10441                 return false;
10442         }
10443 }
10444
10445 /**
10446  * Check if a given expression represents a local variable.
10447  */
10448 static bool expression_is_local_variable(const expression_t *expression)
10449 {
10450         if (expression->base.kind != EXPR_REFERENCE) {
10451                 return false;
10452         }
10453         const entity_t *entity = expression->reference.entity;
10454         return is_local_variable(entity);
10455 }
10456
10457 /**
10458  * Check if a given expression represents a local variable and
10459  * return its declaration then, else return NULL.
10460  */
10461 entity_t *expression_is_variable(const expression_t *expression)
10462 {
10463         if (expression->base.kind != EXPR_REFERENCE) {
10464                 return NULL;
10465         }
10466         entity_t *entity = expression->reference.entity;
10467         if (entity->kind != ENTITY_VARIABLE)
10468                 return NULL;
10469
10470         return entity;
10471 }
10472
10473 /**
10474  * Parse a return statement.
10475  */
10476 static statement_t *parse_return(void)
10477 {
10478         eat(T_return);
10479
10480         statement_t *statement = allocate_statement_zero(STATEMENT_RETURN);
10481
10482         expression_t *return_value = NULL;
10483         if (token.type != ';') {
10484                 return_value = parse_expression();
10485                 mark_vars_read(return_value, NULL);
10486         }
10487
10488         const type_t *const func_type = skip_typeref(current_function->base.type);
10489         assert(is_type_function(func_type));
10490         type_t *const return_type = skip_typeref(func_type->function.return_type);
10491
10492         source_position_t const *const pos = &statement->base.source_position;
10493         if (return_value != NULL) {
10494                 type_t *return_value_type = skip_typeref(return_value->base.type);
10495
10496                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10497                         if (is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
10498                                 /* ISO/IEC 14882:1998(E) §6.6.3:2 */
10499                                 /* Only warn in C mode, because GCC does the same */
10500                                 if (c_mode & _CXX || strict_mode) {
10501                                         errorf(pos,
10502                                                         "'return' with a value, in function returning 'void'");
10503                                 } else if (warning.other) {
10504                                         warningf(pos,
10505                                                         "'return' with a value, in function returning 'void'");
10506                                 }
10507                         } else if (!(c_mode & _CXX)) { /* ISO/IEC 14882:1998(E) §6.6.3:3 */
10508                                 /* Only warn in C mode, because GCC does the same */
10509                                 if (strict_mode) {
10510                                         errorf(pos,
10511                                                         "'return' with expression in function return 'void'");
10512                                 } else if (warning.other) {
10513                                         warningf(pos,
10514                                                         "'return' with expression in function return 'void'");
10515                                 }
10516                         }
10517                 } else {
10518                         assign_error_t error = semantic_assign(return_type, return_value);
10519                         report_assign_error(error, return_type, return_value, "'return'",
10520                                         pos);
10521                 }
10522                 return_value = create_implicit_cast(return_value, return_type);
10523                 /* check for returning address of a local var */
10524                 if (warning.other && return_value != NULL
10525                                 && return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
10526                         const expression_t *expression = return_value->unary.value;
10527                         if (expression_is_local_variable(expression)) {
10528                                 warningf(pos, "function returns address of local variable");
10529                         }
10530                 }
10531         } else if (warning.other && !is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10532                 /* ISO/IEC 14882:1998(E) §6.6.3:3 */
10533                 if (c_mode & _CXX || strict_mode) {
10534                         errorf(pos,
10535                                         "'return' without value, in function returning non-void");
10536                 } else {
10537                         warningf(pos,
10538                                         "'return' without value, in function returning non-void");
10539                 }
10540         }
10541         statement->returns.value = return_value;
10542
10543         expect(';', end_error);
10544
10545 end_error:
10546         return statement;
10547 }
10548
10549 /**
10550  * Parse a declaration statement.
10551  */
10552 static statement_t *parse_declaration_statement(void)
10553 {
10554         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10555
10556         entity_t *before = current_scope->last_entity;
10557         if (GNU_MODE) {
10558                 parse_external_declaration();
10559         } else {
10560                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10561         }
10562
10563         if (before == NULL) {
10564                 statement->declaration.declarations_begin = current_scope->entities;
10565         } else {
10566                 statement->declaration.declarations_begin = before->base.next;
10567         }
10568         statement->declaration.declarations_end = current_scope->last_entity;
10569
10570         return statement;
10571 }
10572
10573 /**
10574  * Parse an expression statement, ie. expr ';'.
10575  */
10576 static statement_t *parse_expression_statement(void)
10577 {
10578         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10579
10580         expression_t *const expr         = parse_expression();
10581         statement->expression.expression = expr;
10582         mark_vars_read(expr, ENT_ANY);
10583
10584         expect(';', end_error);
10585
10586 end_error:
10587         return statement;
10588 }
10589
10590 /**
10591  * Parse a microsoft __try { } __finally { } or
10592  * __try{ } __except() { }
10593  */
10594 static statement_t *parse_ms_try_statment(void)
10595 {
10596         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
10597         eat(T___try);
10598
10599         PUSH_PARENT(statement);
10600
10601         ms_try_statement_t *rem = current_try;
10602         current_try = &statement->ms_try;
10603         statement->ms_try.try_statement = parse_compound_statement(false);
10604         current_try = rem;
10605
10606         POP_PARENT;
10607
10608         if (token.type == T___except) {
10609                 eat(T___except);
10610                 expect('(', end_error);
10611                 add_anchor_token(')');
10612                 expression_t *const expr = parse_expression();
10613                 mark_vars_read(expr, NULL);
10614                 type_t       *      type = skip_typeref(expr->base.type);
10615                 if (is_type_integer(type)) {
10616                         type = promote_integer(type);
10617                 } else if (is_type_valid(type)) {
10618                         errorf(&expr->base.source_position,
10619                                "__expect expression is not an integer, but '%T'", type);
10620                         type = type_error_type;
10621                 }
10622                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
10623                 rem_anchor_token(')');
10624                 expect(')', end_error);
10625                 statement->ms_try.final_statement = parse_compound_statement(false);
10626         } else if (token.type == T__finally) {
10627                 eat(T___finally);
10628                 statement->ms_try.final_statement = parse_compound_statement(false);
10629         } else {
10630                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
10631                 return create_invalid_statement();
10632         }
10633         return statement;
10634 end_error:
10635         return create_invalid_statement();
10636 }
10637
10638 static statement_t *parse_empty_statement(void)
10639 {
10640         if (warning.empty_statement) {
10641                 warningf(HERE, "statement is empty");
10642         }
10643         statement_t *const statement = create_empty_statement();
10644         eat(';');
10645         return statement;
10646 }
10647
10648 static statement_t *parse_local_label_declaration(void)
10649 {
10650         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10651
10652         eat(T___label__);
10653
10654         entity_t *begin = NULL, *end = NULL;
10655
10656         while (true) {
10657                 if (token.type != T_IDENTIFIER) {
10658                         parse_error_expected("while parsing local label declaration",
10659                                 T_IDENTIFIER, NULL);
10660                         goto end_error;
10661                 }
10662                 symbol_t *symbol = token.v.symbol;
10663                 entity_t *entity = get_entity(symbol, NAMESPACE_LABEL);
10664                 if (entity != NULL && entity->base.parent_scope == current_scope) {
10665                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition %P)",
10666                                symbol, &entity->base.source_position);
10667                 } else {
10668                         entity = allocate_entity_zero(ENTITY_LOCAL_LABEL);
10669
10670                         entity->base.parent_scope    = current_scope;
10671                         entity->base.namespc         = NAMESPACE_LABEL;
10672                         entity->base.source_position = token.source_position;
10673                         entity->base.symbol          = symbol;
10674
10675                         if (end != NULL)
10676                                 end->base.next = entity;
10677                         end = entity;
10678                         if (begin == NULL)
10679                                 begin = entity;
10680
10681                         environment_push(entity);
10682                 }
10683                 next_token();
10684
10685                 if (token.type != ',')
10686                         break;
10687                 next_token();
10688         }
10689         eat(';');
10690 end_error:
10691         statement->declaration.declarations_begin = begin;
10692         statement->declaration.declarations_end   = end;
10693         return statement;
10694 }
10695
10696 static void parse_namespace_definition(void)
10697 {
10698         eat(T_namespace);
10699
10700         entity_t *entity = NULL;
10701         symbol_t *symbol = NULL;
10702
10703         if (token.type == T_IDENTIFIER) {
10704                 symbol = token.v.symbol;
10705                 next_token();
10706
10707                 entity = get_entity(symbol, NAMESPACE_NORMAL);
10708                 if (entity != NULL && entity->kind != ENTITY_NAMESPACE
10709                                 && entity->base.parent_scope == current_scope) {
10710                         error_redefined_as_different_kind(&token.source_position,
10711                                                           entity, ENTITY_NAMESPACE);
10712                         entity = NULL;
10713                 }
10714         }
10715
10716         if (entity == NULL) {
10717                 entity                       = allocate_entity_zero(ENTITY_NAMESPACE);
10718                 entity->base.symbol          = symbol;
10719                 entity->base.source_position = token.source_position;
10720                 entity->base.namespc         = NAMESPACE_NORMAL;
10721                 entity->base.parent_scope    = current_scope;
10722         }
10723
10724         if (token.type == '=') {
10725                 /* TODO: parse namespace alias */
10726                 panic("namespace alias definition not supported yet");
10727         }
10728
10729         environment_push(entity);
10730         append_entity(current_scope, entity);
10731
10732         size_t const  top       = environment_top();
10733         scope_t      *old_scope = scope_push(&entity->namespacee.members);
10734
10735         expect('{', end_error);
10736         parse_externals();
10737         expect('}', end_error);
10738
10739 end_error:
10740         assert(current_scope == &entity->namespacee.members);
10741         scope_pop(old_scope);
10742         environment_pop_to(top);
10743 }
10744
10745 /**
10746  * Parse a statement.
10747  * There's also parse_statement() which additionally checks for
10748  * "statement has no effect" warnings
10749  */
10750 static statement_t *intern_parse_statement(void)
10751 {
10752         statement_t *statement = NULL;
10753
10754         /* declaration or statement */
10755         add_anchor_token(';');
10756         switch (token.type) {
10757         case T_IDENTIFIER: {
10758                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
10759                 if (la1_type == ':') {
10760                         statement = parse_label_statement();
10761                 } else if (is_typedef_symbol(token.v.symbol)) {
10762                         statement = parse_declaration_statement();
10763                 } else {
10764                         /* it's an identifier, the grammar says this must be an
10765                          * expression statement. However it is common that users mistype
10766                          * declaration types, so we guess a bit here to improve robustness
10767                          * for incorrect programs */
10768                         switch (la1_type) {
10769                         case '&':
10770                         case '*':
10771                                 if (get_entity(token.v.symbol, NAMESPACE_NORMAL) != NULL)
10772                                         goto expression_statment;
10773                                 /* FALLTHROUGH */
10774
10775                         DECLARATION_START
10776                         case T_IDENTIFIER:
10777                                 statement = parse_declaration_statement();
10778                                 break;
10779
10780                         default:
10781 expression_statment:
10782                                 statement = parse_expression_statement();
10783                                 break;
10784                         }
10785                 }
10786                 break;
10787         }
10788
10789         case T___extension__:
10790                 /* This can be a prefix to a declaration or an expression statement.
10791                  * We simply eat it now and parse the rest with tail recursion. */
10792                 do {
10793                         next_token();
10794                 } while (token.type == T___extension__);
10795                 bool old_gcc_extension = in_gcc_extension;
10796                 in_gcc_extension       = true;
10797                 statement = intern_parse_statement();
10798                 in_gcc_extension = old_gcc_extension;
10799                 break;
10800
10801         DECLARATION_START
10802                 statement = parse_declaration_statement();
10803                 break;
10804
10805         case T___label__:
10806                 statement = parse_local_label_declaration();
10807                 break;
10808
10809         case ';':         statement = parse_empty_statement();         break;
10810         case '{':         statement = parse_compound_statement(false); break;
10811         case T___leave:   statement = parse_leave_statement();         break;
10812         case T___try:     statement = parse_ms_try_statment();         break;
10813         case T_asm:       statement = parse_asm_statement();           break;
10814         case T_break:     statement = parse_break();                   break;
10815         case T_case:      statement = parse_case_statement();          break;
10816         case T_continue:  statement = parse_continue();                break;
10817         case T_default:   statement = parse_default_statement();       break;
10818         case T_do:        statement = parse_do();                      break;
10819         case T_for:       statement = parse_for();                     break;
10820         case T_goto:      statement = parse_goto();                    break;
10821         case T_if:        statement = parse_if();                      break;
10822         case T_return:    statement = parse_return();                  break;
10823         case T_switch:    statement = parse_switch();                  break;
10824         case T_while:     statement = parse_while();                   break;
10825
10826         EXPRESSION_START
10827                 statement = parse_expression_statement();
10828                 break;
10829
10830         default:
10831                 errorf(HERE, "unexpected token %K while parsing statement", &token);
10832                 statement = create_invalid_statement();
10833                 if (!at_anchor())
10834                         next_token();
10835                 break;
10836         }
10837         rem_anchor_token(';');
10838
10839         assert(statement != NULL
10840                         && statement->base.source_position.input_name != NULL);
10841
10842         return statement;
10843 }
10844
10845 /**
10846  * parse a statement and emits "statement has no effect" warning if needed
10847  * (This is really a wrapper around intern_parse_statement with check for 1
10848  *  single warning. It is needed, because for statement expressions we have
10849  *  to avoid the warning on the last statement)
10850  */
10851 static statement_t *parse_statement(void)
10852 {
10853         statement_t *statement = intern_parse_statement();
10854
10855         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
10856                 expression_t *expression = statement->expression.expression;
10857                 if (!expression_has_effect(expression)) {
10858                         warningf(&expression->base.source_position,
10859                                         "statement has no effect");
10860                 }
10861         }
10862
10863         return statement;
10864 }
10865
10866 /**
10867  * Parse a compound statement.
10868  */
10869 static statement_t *parse_compound_statement(bool inside_expression_statement)
10870 {
10871         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
10872
10873         PUSH_PARENT(statement);
10874
10875         eat('{');
10876         add_anchor_token('}');
10877         /* tokens, which can start a statement */
10878         /* TODO MS, __builtin_FOO */
10879         add_anchor_token('!');
10880         add_anchor_token('&');
10881         add_anchor_token('(');
10882         add_anchor_token('*');
10883         add_anchor_token('+');
10884         add_anchor_token('-');
10885         add_anchor_token('{');
10886         add_anchor_token('~');
10887         add_anchor_token(T_CHARACTER_CONSTANT);
10888         add_anchor_token(T_COLONCOLON);
10889         add_anchor_token(T_FLOATINGPOINT);
10890         add_anchor_token(T_IDENTIFIER);
10891         add_anchor_token(T_INTEGER);
10892         add_anchor_token(T_MINUSMINUS);
10893         add_anchor_token(T_PLUSPLUS);
10894         add_anchor_token(T_STRING_LITERAL);
10895         add_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10896         add_anchor_token(T_WIDE_STRING_LITERAL);
10897         add_anchor_token(T__Bool);
10898         add_anchor_token(T__Complex);
10899         add_anchor_token(T__Imaginary);
10900         add_anchor_token(T___FUNCTION__);
10901         add_anchor_token(T___PRETTY_FUNCTION__);
10902         add_anchor_token(T___alignof__);
10903         add_anchor_token(T___attribute__);
10904         add_anchor_token(T___builtin_va_start);
10905         add_anchor_token(T___extension__);
10906         add_anchor_token(T___func__);
10907         add_anchor_token(T___imag__);
10908         add_anchor_token(T___label__);
10909         add_anchor_token(T___real__);
10910         add_anchor_token(T___thread);
10911         add_anchor_token(T_asm);
10912         add_anchor_token(T_auto);
10913         add_anchor_token(T_bool);
10914         add_anchor_token(T_break);
10915         add_anchor_token(T_case);
10916         add_anchor_token(T_char);
10917         add_anchor_token(T_class);
10918         add_anchor_token(T_const);
10919         add_anchor_token(T_const_cast);
10920         add_anchor_token(T_continue);
10921         add_anchor_token(T_default);
10922         add_anchor_token(T_delete);
10923         add_anchor_token(T_double);
10924         add_anchor_token(T_do);
10925         add_anchor_token(T_dynamic_cast);
10926         add_anchor_token(T_enum);
10927         add_anchor_token(T_extern);
10928         add_anchor_token(T_false);
10929         add_anchor_token(T_float);
10930         add_anchor_token(T_for);
10931         add_anchor_token(T_goto);
10932         add_anchor_token(T_if);
10933         add_anchor_token(T_inline);
10934         add_anchor_token(T_int);
10935         add_anchor_token(T_long);
10936         add_anchor_token(T_new);
10937         add_anchor_token(T_operator);
10938         add_anchor_token(T_register);
10939         add_anchor_token(T_reinterpret_cast);
10940         add_anchor_token(T_restrict);
10941         add_anchor_token(T_return);
10942         add_anchor_token(T_short);
10943         add_anchor_token(T_signed);
10944         add_anchor_token(T_sizeof);
10945         add_anchor_token(T_static);
10946         add_anchor_token(T_static_cast);
10947         add_anchor_token(T_struct);
10948         add_anchor_token(T_switch);
10949         add_anchor_token(T_template);
10950         add_anchor_token(T_this);
10951         add_anchor_token(T_throw);
10952         add_anchor_token(T_true);
10953         add_anchor_token(T_try);
10954         add_anchor_token(T_typedef);
10955         add_anchor_token(T_typeid);
10956         add_anchor_token(T_typename);
10957         add_anchor_token(T_typeof);
10958         add_anchor_token(T_union);
10959         add_anchor_token(T_unsigned);
10960         add_anchor_token(T_using);
10961         add_anchor_token(T_void);
10962         add_anchor_token(T_volatile);
10963         add_anchor_token(T_wchar_t);
10964         add_anchor_token(T_while);
10965
10966         size_t const  top       = environment_top();
10967         scope_t      *old_scope = scope_push(&statement->compound.scope);
10968
10969         statement_t **anchor            = &statement->compound.statements;
10970         bool          only_decls_so_far = true;
10971         while (token.type != '}') {
10972                 if (token.type == T_EOF) {
10973                         errorf(&statement->base.source_position,
10974                                "EOF while parsing compound statement");
10975                         break;
10976                 }
10977                 statement_t *sub_statement = intern_parse_statement();
10978                 if (is_invalid_statement(sub_statement)) {
10979                         /* an error occurred. if we are at an anchor, return */
10980                         if (at_anchor())
10981                                 goto end_error;
10982                         continue;
10983                 }
10984
10985                 if (warning.declaration_after_statement) {
10986                         if (sub_statement->kind != STATEMENT_DECLARATION) {
10987                                 only_decls_so_far = false;
10988                         } else if (!only_decls_so_far) {
10989                                 warningf(&sub_statement->base.source_position,
10990                                          "ISO C90 forbids mixed declarations and code");
10991                         }
10992                 }
10993
10994                 *anchor = sub_statement;
10995
10996                 while (sub_statement->base.next != NULL)
10997                         sub_statement = sub_statement->base.next;
10998
10999                 anchor = &sub_statement->base.next;
11000         }
11001         next_token();
11002
11003         /* look over all statements again to produce no effect warnings */
11004         if (warning.unused_value) {
11005                 statement_t *sub_statement = statement->compound.statements;
11006                 for (; sub_statement != NULL; sub_statement = sub_statement->base.next) {
11007                         if (sub_statement->kind != STATEMENT_EXPRESSION)
11008                                 continue;
11009                         /* don't emit a warning for the last expression in an expression
11010                          * statement as it has always an effect */
11011                         if (inside_expression_statement && sub_statement->base.next == NULL)
11012                                 continue;
11013
11014                         expression_t *expression = sub_statement->expression.expression;
11015                         if (!expression_has_effect(expression)) {
11016                                 warningf(&expression->base.source_position,
11017                                          "statement has no effect");
11018                         }
11019                 }
11020         }
11021
11022 end_error:
11023         rem_anchor_token(T_while);
11024         rem_anchor_token(T_wchar_t);
11025         rem_anchor_token(T_volatile);
11026         rem_anchor_token(T_void);
11027         rem_anchor_token(T_using);
11028         rem_anchor_token(T_unsigned);
11029         rem_anchor_token(T_union);
11030         rem_anchor_token(T_typeof);
11031         rem_anchor_token(T_typename);
11032         rem_anchor_token(T_typeid);
11033         rem_anchor_token(T_typedef);
11034         rem_anchor_token(T_try);
11035         rem_anchor_token(T_true);
11036         rem_anchor_token(T_throw);
11037         rem_anchor_token(T_this);
11038         rem_anchor_token(T_template);
11039         rem_anchor_token(T_switch);
11040         rem_anchor_token(T_struct);
11041         rem_anchor_token(T_static_cast);
11042         rem_anchor_token(T_static);
11043         rem_anchor_token(T_sizeof);
11044         rem_anchor_token(T_signed);
11045         rem_anchor_token(T_short);
11046         rem_anchor_token(T_return);
11047         rem_anchor_token(T_restrict);
11048         rem_anchor_token(T_reinterpret_cast);
11049         rem_anchor_token(T_register);
11050         rem_anchor_token(T_operator);
11051         rem_anchor_token(T_new);
11052         rem_anchor_token(T_long);
11053         rem_anchor_token(T_int);
11054         rem_anchor_token(T_inline);
11055         rem_anchor_token(T_if);
11056         rem_anchor_token(T_goto);
11057         rem_anchor_token(T_for);
11058         rem_anchor_token(T_float);
11059         rem_anchor_token(T_false);
11060         rem_anchor_token(T_extern);
11061         rem_anchor_token(T_enum);
11062         rem_anchor_token(T_dynamic_cast);
11063         rem_anchor_token(T_do);
11064         rem_anchor_token(T_double);
11065         rem_anchor_token(T_delete);
11066         rem_anchor_token(T_default);
11067         rem_anchor_token(T_continue);
11068         rem_anchor_token(T_const_cast);
11069         rem_anchor_token(T_const);
11070         rem_anchor_token(T_class);
11071         rem_anchor_token(T_char);
11072         rem_anchor_token(T_case);
11073         rem_anchor_token(T_break);
11074         rem_anchor_token(T_bool);
11075         rem_anchor_token(T_auto);
11076         rem_anchor_token(T_asm);
11077         rem_anchor_token(T___thread);
11078         rem_anchor_token(T___real__);
11079         rem_anchor_token(T___label__);
11080         rem_anchor_token(T___imag__);
11081         rem_anchor_token(T___func__);
11082         rem_anchor_token(T___extension__);
11083         rem_anchor_token(T___builtin_va_start);
11084         rem_anchor_token(T___attribute__);
11085         rem_anchor_token(T___alignof__);
11086         rem_anchor_token(T___PRETTY_FUNCTION__);
11087         rem_anchor_token(T___FUNCTION__);
11088         rem_anchor_token(T__Imaginary);
11089         rem_anchor_token(T__Complex);
11090         rem_anchor_token(T__Bool);
11091         rem_anchor_token(T_WIDE_STRING_LITERAL);
11092         rem_anchor_token(T_WIDE_CHARACTER_CONSTANT);
11093         rem_anchor_token(T_STRING_LITERAL);
11094         rem_anchor_token(T_PLUSPLUS);
11095         rem_anchor_token(T_MINUSMINUS);
11096         rem_anchor_token(T_INTEGER);
11097         rem_anchor_token(T_IDENTIFIER);
11098         rem_anchor_token(T_FLOATINGPOINT);
11099         rem_anchor_token(T_COLONCOLON);
11100         rem_anchor_token(T_CHARACTER_CONSTANT);
11101         rem_anchor_token('~');
11102         rem_anchor_token('{');
11103         rem_anchor_token('-');
11104         rem_anchor_token('+');
11105         rem_anchor_token('*');
11106         rem_anchor_token('(');
11107         rem_anchor_token('&');
11108         rem_anchor_token('!');
11109         rem_anchor_token('}');
11110         assert(current_scope == &statement->compound.scope);
11111         scope_pop(old_scope);
11112         environment_pop_to(top);
11113
11114         POP_PARENT;
11115         return statement;
11116 }
11117
11118 /**
11119  * Check for unused global static functions and variables
11120  */
11121 static void check_unused_globals(void)
11122 {
11123         if (!warning.unused_function && !warning.unused_variable)
11124                 return;
11125
11126         for (const entity_t *entity = file_scope->entities; entity != NULL;
11127              entity = entity->base.next) {
11128                 if (!is_declaration(entity))
11129                         continue;
11130
11131                 const declaration_t *declaration = &entity->declaration;
11132                 if (declaration->used                  ||
11133                     declaration->modifiers & DM_UNUSED ||
11134                     declaration->modifiers & DM_USED   ||
11135                     declaration->storage_class != STORAGE_CLASS_STATIC)
11136                         continue;
11137
11138                 type_t *const type = declaration->type;
11139                 const char *s;
11140                 if (entity->kind == ENTITY_FUNCTION) {
11141                         /* inhibit warning for static inline functions */
11142                         if (entity->function.is_inline)
11143                                 continue;
11144
11145                         s = entity->function.statement != NULL ? "defined" : "declared";
11146                 } else {
11147                         s = "defined";
11148                 }
11149
11150                 warningf(&declaration->base.source_position, "'%#T' %s but not used",
11151                         type, declaration->base.symbol, s);
11152         }
11153 }
11154
11155 static void parse_global_asm(void)
11156 {
11157         statement_t *statement = allocate_statement_zero(STATEMENT_ASM);
11158
11159         eat(T_asm);
11160         expect('(', end_error);
11161
11162         statement->asms.asm_text = parse_string_literals();
11163         statement->base.next     = unit->global_asm;
11164         unit->global_asm         = statement;
11165
11166         expect(')', end_error);
11167         expect(';', end_error);
11168
11169 end_error:;
11170 }
11171
11172 static void parse_linkage_specification(void)
11173 {
11174         eat(T_extern);
11175         assert(token.type == T_STRING_LITERAL);
11176
11177         const char *linkage = parse_string_literals().begin;
11178
11179         linkage_kind_t old_linkage = current_linkage;
11180         linkage_kind_t new_linkage;
11181         if (strcmp(linkage, "C") == 0) {
11182                 new_linkage = LINKAGE_C;
11183         } else if (strcmp(linkage, "C++") == 0) {
11184                 new_linkage = LINKAGE_CXX;
11185         } else {
11186                 errorf(HERE, "linkage string \"%s\" not recognized", linkage);
11187                 new_linkage = LINKAGE_INVALID;
11188         }
11189         current_linkage = new_linkage;
11190
11191         if (token.type == '{') {
11192                 next_token();
11193                 parse_externals();
11194                 expect('}', end_error);
11195         } else {
11196                 parse_external();
11197         }
11198
11199 end_error:
11200         assert(current_linkage == new_linkage);
11201         current_linkage = old_linkage;
11202 }
11203
11204 static void parse_external(void)
11205 {
11206         switch (token.type) {
11207                 DECLARATION_START_NO_EXTERN
11208                 case T_IDENTIFIER:
11209                 case T___extension__:
11210                 /* tokens below are for implicit int */
11211                 case '&': /* & x; -> int& x; (and error later, because C++ has no
11212                              implicit int) */
11213                 case '*': /* * x; -> int* x; */
11214                 case '(': /* (x); -> int (x); */
11215                         parse_external_declaration();
11216                         return;
11217
11218                 case T_extern:
11219                         if (look_ahead(1)->type == T_STRING_LITERAL) {
11220                                 parse_linkage_specification();
11221                         } else {
11222                                 parse_external_declaration();
11223                         }
11224                         return;
11225
11226                 case T_asm:
11227                         parse_global_asm();
11228                         return;
11229
11230                 case T_namespace:
11231                         parse_namespace_definition();
11232                         return;
11233
11234                 case ';':
11235                         if (!strict_mode) {
11236                                 if (warning.other)
11237                                         warningf(HERE, "stray ';' outside of function");
11238                                 next_token();
11239                                 return;
11240                         }
11241                         /* FALLTHROUGH */
11242
11243                 default:
11244                         errorf(HERE, "stray %K outside of function", &token);
11245                         if (token.type == '(' || token.type == '{' || token.type == '[')
11246                                 eat_until_matching_token(token.type);
11247                         next_token();
11248                         return;
11249         }
11250 }
11251
11252 static void parse_externals(void)
11253 {
11254         add_anchor_token('}');
11255         add_anchor_token(T_EOF);
11256
11257 #ifndef NDEBUG
11258         unsigned char token_anchor_copy[T_LAST_TOKEN];
11259         memcpy(token_anchor_copy, token_anchor_set, sizeof(token_anchor_copy));
11260 #endif
11261
11262         while (token.type != T_EOF && token.type != '}') {
11263 #ifndef NDEBUG
11264                 bool anchor_leak = false;
11265                 for (int i = 0; i != T_LAST_TOKEN; ++i) {
11266                         unsigned char count = token_anchor_set[i] - token_anchor_copy[i];
11267                         if (count != 0) {
11268                                 errorf(HERE, "Leaked anchor token %k %d times", i, count);
11269                                 anchor_leak = true;
11270                         }
11271                 }
11272                 if (in_gcc_extension) {
11273                         errorf(HERE, "Leaked __extension__");
11274                         anchor_leak = true;
11275                 }
11276
11277                 if (anchor_leak)
11278                         abort();
11279 #endif
11280
11281                 parse_external();
11282         }
11283
11284         rem_anchor_token(T_EOF);
11285         rem_anchor_token('}');
11286 }
11287
11288 /**
11289  * Parse a translation unit.
11290  */
11291 static void parse_translation_unit(void)
11292 {
11293         add_anchor_token(T_EOF);
11294
11295         while (true) {
11296                 parse_externals();
11297
11298                 if (token.type == T_EOF)
11299                         break;
11300
11301                 errorf(HERE, "stray %K outside of function", &token);
11302                 if (token.type == '(' || token.type == '{' || token.type == '[')
11303                         eat_until_matching_token(token.type);
11304                 next_token();
11305         }
11306 }
11307
11308 /**
11309  * Parse the input.
11310  *
11311  * @return  the translation unit or NULL if errors occurred.
11312  */
11313 void start_parsing(void)
11314 {
11315         environment_stack = NEW_ARR_F(stack_entry_t, 0);
11316         label_stack       = NEW_ARR_F(stack_entry_t, 0);
11317         diagnostic_count  = 0;
11318         error_count       = 0;
11319         warning_count     = 0;
11320
11321         type_set_output(stderr);
11322         ast_set_output(stderr);
11323
11324         assert(unit == NULL);
11325         unit = allocate_ast_zero(sizeof(unit[0]));
11326
11327         assert(file_scope == NULL);
11328         file_scope = &unit->scope;
11329
11330         assert(current_scope == NULL);
11331         scope_push(&unit->scope);
11332 }
11333
11334 translation_unit_t *finish_parsing(void)
11335 {
11336         assert(current_scope == &unit->scope);
11337         scope_pop(NULL);
11338
11339         assert(file_scope == &unit->scope);
11340         check_unused_globals();
11341         file_scope = NULL;
11342
11343         DEL_ARR_F(environment_stack);
11344         DEL_ARR_F(label_stack);
11345
11346         translation_unit_t *result = unit;
11347         unit = NULL;
11348         return result;
11349 }
11350
11351 /* GCC allows global arrays without size and assigns them a length of one,
11352  * if no different declaration follows */
11353 static void complete_incomplete_arrays(void)
11354 {
11355         size_t n = ARR_LEN(incomplete_arrays);
11356         for (size_t i = 0; i != n; ++i) {
11357                 declaration_t *const decl      = incomplete_arrays[i];
11358                 type_t        *const orig_type = decl->type;
11359                 type_t        *const type      = skip_typeref(orig_type);
11360
11361                 if (!is_type_incomplete(type))
11362                         continue;
11363
11364                 if (warning.other) {
11365                         warningf(&decl->base.source_position,
11366                                         "array '%#T' assumed to have one element",
11367                                         orig_type, decl->base.symbol);
11368                 }
11369
11370                 type_t *const new_type = duplicate_type(type);
11371                 new_type->array.size_constant     = true;
11372                 new_type->array.has_implicit_size = true;
11373                 new_type->array.size              = 1;
11374
11375                 type_t *const result = typehash_insert(new_type);
11376                 if (type != result)
11377                         free_type(type);
11378
11379                 decl->type = result;
11380         }
11381 }
11382
11383 void parse(void)
11384 {
11385         lookahead_bufpos = 0;
11386         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
11387                 next_token();
11388         }
11389         current_linkage   = c_mode & _CXX ? LINKAGE_CXX : LINKAGE_C;
11390         incomplete_arrays = NEW_ARR_F(declaration_t*, 0);
11391         parse_translation_unit();
11392         complete_incomplete_arrays();
11393         DEL_ARR_F(incomplete_arrays);
11394         incomplete_arrays = NULL;
11395 }
11396
11397 /**
11398  * Initialize the parser.
11399  */
11400 void init_parser(void)
11401 {
11402         sym_anonymous = symbol_table_insert("<anonymous>");
11403
11404         if (c_mode & _MS) {
11405                 /* add predefined symbols for extended-decl-modifier */
11406                 sym_align         = symbol_table_insert("align");
11407                 sym_allocate      = symbol_table_insert("allocate");
11408                 sym_dllimport     = symbol_table_insert("dllimport");
11409                 sym_dllexport     = symbol_table_insert("dllexport");
11410                 sym_naked         = symbol_table_insert("naked");
11411                 sym_noinline      = symbol_table_insert("noinline");
11412                 sym_returns_twice = symbol_table_insert("returns_twice");
11413                 sym_noreturn      = symbol_table_insert("noreturn");
11414                 sym_nothrow       = symbol_table_insert("nothrow");
11415                 sym_novtable      = symbol_table_insert("novtable");
11416                 sym_property      = symbol_table_insert("property");
11417                 sym_get           = symbol_table_insert("get");
11418                 sym_put           = symbol_table_insert("put");
11419                 sym_selectany     = symbol_table_insert("selectany");
11420                 sym_thread        = symbol_table_insert("thread");
11421                 sym_uuid          = symbol_table_insert("uuid");
11422                 sym_deprecated    = symbol_table_insert("deprecated");
11423                 sym_restrict      = symbol_table_insert("restrict");
11424                 sym_noalias       = symbol_table_insert("noalias");
11425         }
11426         memset(token_anchor_set, 0, sizeof(token_anchor_set));
11427
11428         init_expression_parsers();
11429         obstack_init(&temp_obst);
11430
11431         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
11432         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
11433 }
11434
11435 /**
11436  * Terminate the parser.
11437  */
11438 void exit_parser(void)
11439 {
11440         obstack_free(&temp_obst, NULL);
11441 }