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