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_noreturn   = NULL;
 160 static const symbol_t *sym_nothrow    = NULL;
 161 static const symbol_t *sym_novtable   = NULL;
 162 static const symbol_t *sym_property   = NULL;
 163 static const symbol_t *sym_get        = NULL;
 164 static const symbol_t *sym_put        = NULL;
 165 static const symbol_t *sym_selectany  = NULL;
 166 static const symbol_t *sym_thread     = NULL;
 167 static const symbol_t *sym_uuid       = NULL;
 168 static const symbol_t *sym_deprecated = NULL;
 169 static const symbol_t *sym_restrict   = NULL;
 170 static const symbol_t *sym_noalias    = NULL;
 171
 172 /** The token anchor set */
 173 static unsigned char token_anchor_set[T_LAST_TOKEN];
 174
 175 /** The current source position. */
 176 #define HERE (&token.source_position)
 177
 178 /** true if we are in GCC mode. */
 179 #define GNU_MODE ((c_mode & _GNUC) || in_gcc_extension)
 180
 181 static type_t *type_valist;
 182
 183 static statement_t *parse_compound_statement(bool inside_expression_statement);
 184 static statement_t *parse_statement(void);
 185
 186 static expression_t *parse_sub_expression(precedence_t);
 187 static expression_t *parse_expression(void);
 188 static type_t       *parse_typename(void);
 189 static void          parse_externals(void);
 190 static void          parse_external(void);
 191
 192 static void parse_compound_type_entries(compound_t *compound_declaration);
 193
 194 typedef enum declarator_flags_t {
 195         DECL_FLAGS_NONE             = 0,
 196         DECL_MAY_BE_ABSTRACT        = 1U << 0,
 197         DECL_CREATE_COMPOUND_MEMBER = 1U << 1,
 198         DECL_IS_PARAMETER           = 1U << 2
 199 } declarator_flags_t;
 200
 201 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
 202                                   declarator_flags_t flags);
 203
 204 static entity_t *record_entity(entity_t *entity, bool is_definition);
 205
 206 static void semantic_comparison(binary_expression_t *expression);
 207
 208 #define STORAGE_CLASSES       \
 209         STORAGE_CLASSES_NO_EXTERN \
 210         case T_extern:
 211
 212 #define STORAGE_CLASSES_NO_EXTERN \
 213         case T_typedef:         \
 214         case T_static:          \
 215         case T_auto:            \
 216         case T_register:        \
 217         case T___thread:
 218
 219 #define TYPE_QUALIFIERS     \
 220         case T_const:           \
 221         case T_restrict:        \
 222         case T_volatile:        \
 223         case T_inline:          \
 224         case T__forceinline:    \
 225         case T___attribute__:
 226
 227 #define COMPLEX_SPECIFIERS  \
 228         case T__Complex:
 229 #define IMAGINARY_SPECIFIERS \
 230         case T__Imaginary:
 231
 232 #define TYPE_SPECIFIERS       \
 233         case T__Bool:             \
 234         case T___builtin_va_list: \
 235         case T___typeof__:        \
 236         case T__declspec:         \
 237         case T_bool:              \
 238         case T_char:              \
 239         case T_double:            \
 240         case T_enum:              \
 241         case T_float:             \
 242         case T_int:               \
 243         case T_long:              \
 244         case T_short:             \
 245         case T_signed:            \
 246         case T_struct:            \
 247         case T_union:             \
 248         case T_unsigned:          \
 249         case T_void:              \
 250         COMPLEX_SPECIFIERS        \
 251         IMAGINARY_SPECIFIERS
 252
 253 #define DECLARATION_START   \
 254         STORAGE_CLASSES         \
 255         TYPE_QUALIFIERS         \
 256         TYPE_SPECIFIERS
 257
 258 #define DECLARATION_START_NO_EXTERN \
 259         STORAGE_CLASSES_NO_EXTERN       \
 260         TYPE_QUALIFIERS                 \
 261         TYPE_SPECIFIERS
 262
 263 #define TYPENAME_START      \
 264         TYPE_QUALIFIERS         \
 265         TYPE_SPECIFIERS
 266
 267 #define EXPRESSION_START           \
 268         case '!':                        \
 269         case '&':                        \
 270         case '(':                        \
 271         case '*':                        \
 272         case '+':                        \
 273         case '-':                        \
 274         case '~':                        \
 275         case T_ANDAND:                   \
 276         case T_CHARACTER_CONSTANT:       \
 277         case T_FLOATINGPOINT:            \
 278         case T_INTEGER:                  \
 279         case T_MINUSMINUS:               \
 280         case T_PLUSPLUS:                 \
 281         case T_STRING_LITERAL:           \
 282         case T_WIDE_CHARACTER_CONSTANT:  \
 283         case T_WIDE_STRING_LITERAL:      \
 284         case T___FUNCDNAME__:            \
 285         case T___FUNCSIG__:              \
 286         case T___FUNCTION__:             \
 287         case T___PRETTY_FUNCTION__:      \
 288         case T___alignof__:              \
 289         case T___builtin_alloca:         \
 290         case T___builtin_classify_type:  \
 291         case T___builtin_constant_p:     \
 292         case T___builtin_expect:         \
 293         case T___builtin_huge_val:       \
 294         case T___builtin_inf:            \
 295         case T___builtin_inff:           \
 296         case T___builtin_infl:           \
 297         case T___builtin_isgreater:      \
 298         case T___builtin_isgreaterequal: \
 299         case T___builtin_isless:         \
 300         case T___builtin_islessequal:    \
 301         case T___builtin_islessgreater:  \
 302         case T___builtin_isunordered:    \
 303         case T___builtin_nan:            \
 304         case T___builtin_nanf:           \
 305         case T___builtin_nanl:           \
 306         case T___builtin_offsetof:       \
 307         case T___builtin_prefetch:       \
 308         case T___builtin_va_arg:         \
 309         case T___builtin_va_end:         \
 310         case T___builtin_va_start:       \
 311         case T___func__:                 \
 312         case T___noop:                   \
 313         case T__assume:                  \
 314         case T_delete:                   \
 315         case T_false:                    \
 316         case T_sizeof:                   \
 317         case T_throw:                    \
 318         case T_true:
 319
 320 /**
 321  * Allocate an AST node with given size and
 322  * initialize all fields with zero.
 323  */
 324 static void *allocate_ast_zero(size_t size)
 325 {
 326         void *res = allocate_ast(size);
 327         memset(res, 0, size);
 328         return res;
 329 }
 330
 331 /**
 332  * Returns the size of an entity node.
 333  *
 334  * @param kind  the entity kind
 335  */
 336 static size_t get_entity_struct_size(entity_kind_t kind)
 337 {
 338         static const size_t sizes[] = {
 339                 [ENTITY_VARIABLE]        = sizeof(variable_t),
 340                 [ENTITY_PARAMETER]       = sizeof(parameter_t),
 341                 [ENTITY_COMPOUND_MEMBER] = sizeof(compound_member_t),
 342                 [ENTITY_FUNCTION]        = sizeof(function_t),
 343                 [ENTITY_TYPEDEF]         = sizeof(typedef_t),
 344                 [ENTITY_STRUCT]          = sizeof(compound_t),
 345                 [ENTITY_UNION]           = sizeof(compound_t),
 346                 [ENTITY_ENUM]            = sizeof(enum_t),
 347                 [ENTITY_ENUM_VALUE]      = sizeof(enum_value_t),
 348                 [ENTITY_LABEL]           = sizeof(label_t),
 349                 [ENTITY_LOCAL_LABEL]     = sizeof(label_t),
 350                 [ENTITY_NAMESPACE]       = sizeof(namespace_t)
 351         };
 352         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 353         assert(sizes[kind] != 0);
 354         return sizes[kind];
 355 }
 356
 357 /**
 358  * Allocate an entity of given kind and initialize all
 359  * fields with zero.
 360  */
 361 static entity_t *allocate_entity_zero(entity_kind_t kind)
 362 {
 363         size_t    size   = get_entity_struct_size(kind);
 364         entity_t *entity = allocate_ast_zero(size);
 365         entity->kind     = kind;
 366         return entity;
 367 }
 368
 369 /**
 370  * Returns the size of a statement node.
 371  *
 372  * @param kind  the statement kind
 373  */
 374 static size_t get_statement_struct_size(statement_kind_t kind)
 375 {
 376         static const size_t sizes[] = {
 377                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 378                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 379                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 380                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 381                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 382                 [STATEMENT_LOCAL_LABEL] = sizeof(local_label_statement_t),
 383                 [STATEMENT_IF]          = sizeof(if_statement_t),
 384                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 385                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 386                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 387                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 388                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 389                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 390                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 391                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 392                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 393                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 394                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 395                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 396                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 397         };
 398         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 399         assert(sizes[kind] != 0);
 400         return sizes[kind];
 401 }
 402
 403 /**
 404  * Returns the size of an expression node.
 405  *
 406  * @param kind  the expression kind
 407  */
 408 static size_t get_expression_struct_size(expression_kind_t kind)
 409 {
 410         static const size_t sizes[] = {
 411                 [EXPR_INVALID]                 = sizeof(expression_base_t),
 412                 [EXPR_REFERENCE]               = sizeof(reference_expression_t),
 413                 [EXPR_REFERENCE_ENUM_VALUE]    = sizeof(reference_expression_t),
 414                 [EXPR_CONST]                   = sizeof(const_expression_t),
 415                 [EXPR_CHARACTER_CONSTANT]      = sizeof(const_expression_t),
 416                 [EXPR_WIDE_CHARACTER_CONSTANT] = sizeof(const_expression_t),
 417                 [EXPR_STRING_LITERAL]          = sizeof(string_literal_expression_t),
 418                 [EXPR_WIDE_STRING_LITERAL]     = sizeof(wide_string_literal_expression_t),
 419                 [EXPR_COMPOUND_LITERAL]        = sizeof(compound_literal_expression_t),
 420                 [EXPR_CALL]                    = sizeof(call_expression_t),
 421                 [EXPR_UNARY_FIRST]             = sizeof(unary_expression_t),
 422                 [EXPR_BINARY_FIRST]            = sizeof(binary_expression_t),
 423                 [EXPR_CONDITIONAL]             = sizeof(conditional_expression_t),
 424                 [EXPR_SELECT]                  = sizeof(select_expression_t),
 425                 [EXPR_ARRAY_ACCESS]            = sizeof(array_access_expression_t),
 426                 [EXPR_SIZEOF]                  = sizeof(typeprop_expression_t),
 427                 [EXPR_ALIGNOF]                 = sizeof(typeprop_expression_t),
 428                 [EXPR_CLASSIFY_TYPE]           = sizeof(classify_type_expression_t),
 429                 [EXPR_FUNCNAME]                = sizeof(funcname_expression_t),
 430                 [EXPR_BUILTIN_SYMBOL]          = sizeof(builtin_symbol_expression_t),
 431                 [EXPR_BUILTIN_CONSTANT_P]      = sizeof(builtin_constant_expression_t),
 432                 [EXPR_BUILTIN_PREFETCH]        = sizeof(builtin_prefetch_expression_t),
 433                 [EXPR_OFFSETOF]                = sizeof(offsetof_expression_t),
 434                 [EXPR_VA_START]                = sizeof(va_start_expression_t),
 435                 [EXPR_VA_ARG]                  = sizeof(va_arg_expression_t),
 436                 [EXPR_STATEMENT]               = sizeof(statement_expression_t),
 437                 [EXPR_LABEL_ADDRESS]           = sizeof(label_address_expression_t),
 438         };
 439         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 440                 return sizes[EXPR_UNARY_FIRST];
 441         }
 442         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 443                 return sizes[EXPR_BINARY_FIRST];
 444         }
 445         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 446         assert(sizes[kind] != 0);
 447         return sizes[kind];
 448 }
 449
 450 /**
 451  * Allocate a statement node of given kind and initialize all
 452  * fields with zero. Sets its source position to the position
 453  * of the current token.
 454  */
 455 static statement_t *allocate_statement_zero(statement_kind_t kind)
 456 {
 457         size_t       size = get_statement_struct_size(kind);
 458         statement_t *res  = allocate_ast_zero(size);
 459
 460         res->base.kind            = kind;
 461         res->base.parent          = current_parent;
 462         res->base.source_position = token.source_position;
 463         return res;
 464 }
 465
 466 /**
 467  * Allocate an expression node of given kind and initialize all
 468  * fields with zero.
 469  */
 470 static expression_t *allocate_expression_zero(expression_kind_t kind)
 471 {
 472         size_t        size = get_expression_struct_size(kind);
 473         expression_t *res  = allocate_ast_zero(size);
 474
 475         res->base.kind            = kind;
 476         res->base.type            = type_error_type;
 477         res->base.source_position = token.source_position;
 478         return res;
 479 }
 480
 481 /**
 482  * Creates a new invalid expression at the source position
 483  * of the current token.
 484  */
 485 static expression_t *create_invalid_expression(void)
 486 {
 487         return allocate_expression_zero(EXPR_INVALID);
 488 }
 489
 490 /**
 491  * Creates a new invalid statement.
 492  */
 493 static statement_t *create_invalid_statement(void)
 494 {
 495         return allocate_statement_zero(STATEMENT_INVALID);
 496 }
 497
 498 /**
 499  * Allocate a new empty statement.
 500  */
 501 static statement_t *create_empty_statement(void)
 502 {
 503         return allocate_statement_zero(STATEMENT_EMPTY);
 504 }
 505
 506 /**
 507  * Returns the size of a type node.
 508  *
 509  * @param kind  the type kind
 510  */
 511 static size_t get_type_struct_size(type_kind_t kind)
 512 {
 513         static const size_t sizes[] = {
 514                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
 515                 [TYPE_COMPLEX]         = sizeof(complex_type_t),
 516                 [TYPE_IMAGINARY]       = sizeof(imaginary_type_t),
 517                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
 518                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
 519                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
 520                 [TYPE_ENUM]            = sizeof(enum_type_t),
 521                 [TYPE_FUNCTION]        = sizeof(function_type_t),
 522                 [TYPE_POINTER]         = sizeof(pointer_type_t),
 523                 [TYPE_ARRAY]           = sizeof(array_type_t),
 524                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
 525                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
 526                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
 527         };
 528         assert(sizeof(sizes) / sizeof(sizes[0]) == (int) TYPE_TYPEOF + 1);
 529         assert(kind <= TYPE_TYPEOF);
 530         assert(sizes[kind] != 0);
 531         return sizes[kind];
 532 }
 533
 534 /**
 535  * Allocate a type node of given kind and initialize all
 536  * fields with zero.
 537  *
 538  * @param kind             type kind to allocate
 539  */
 540 static type_t *allocate_type_zero(type_kind_t kind)
 541 {
 542         size_t  size = get_type_struct_size(kind);
 543         type_t *res  = obstack_alloc(type_obst, size);
 544         memset(res, 0, size);
 545         res->base.kind = kind;
 546
 547         return res;
 548 }
 549
 550 /**
 551  * Returns the size of an initializer node.
 552  *
 553  * @param kind  the initializer kind
 554  */
 555 static size_t get_initializer_size(initializer_kind_t kind)
 556 {
 557         static const size_t sizes[] = {
 558                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 559                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 560                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 561                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 562                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 563         };
 564         assert(kind < sizeof(sizes) / sizeof(*sizes));
 565         assert(sizes[kind] != 0);
 566         return sizes[kind];
 567 }
 568
 569 /**
 570  * Allocate an initializer node of given kind and initialize all
 571  * fields with zero.
 572  */
 573 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 574 {
 575         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 576         result->kind          = kind;
 577
 578         return result;
 579 }
 580
 581 /**
 582  * Free a type from the type obstack.
 583  */
 584 static void free_type(void *type)
 585 {
 586         obstack_free(type_obst, type);
 587 }
 588
 589 /**
 590  * Returns the index of the top element of the environment stack.
 591  */
 592 static size_t environment_top(void)
 593 {
 594         return ARR_LEN(environment_stack);
 595 }
 596
 597 /**
 598  * Returns the index of the top element of the global label stack.
 599  */
 600 static size_t label_top(void)
 601 {
 602         return ARR_LEN(label_stack);
 603 }
 604
 605 /**
 606  * Return the next token.
 607  */
 608 static inline void next_token(void)
 609 {
 610         token                              = lookahead_buffer[lookahead_bufpos];
 611         lookahead_buffer[lookahead_bufpos] = lexer_token;
 612         lexer_next_token();
 613
 614         lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
 615
 616 #ifdef PRINT_TOKENS
 617         print_token(stderr, &token);
 618         fprintf(stderr, "\n");
 619 #endif
 620 }
 621
 622 /**
 623  * Return the next token with a given lookahead.
 624  */
 625 static inline const token_t *look_ahead(int num)
 626 {
 627         assert(num > 0 && num <= MAX_LOOKAHEAD);
 628         int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
 629         return &lookahead_buffer[pos];
 630 }
 631
 632 /**
 633  * Adds a token type to the token type anchor set (a multi-set).
 634  */
 635 static void add_anchor_token(int token_type)
 636 {
 637         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 638         ++token_anchor_set[token_type];
 639 }
 640
 641 /**
 642  * Set the number of tokens types of the given type
 643  * to zero and return the old count.
 644  */
 645 static int save_and_reset_anchor_state(int token_type)
 646 {
 647         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 648         int count = token_anchor_set[token_type];
 649         token_anchor_set[token_type] = 0;
 650         return count;
 651 }
 652
 653 /**
 654  * Restore the number of token types to the given count.
 655  */
 656 static void restore_anchor_state(int token_type, int count)
 657 {
 658         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 659         token_anchor_set[token_type] = count;
 660 }
 661
 662 /**
 663  * Remove a token type from the token type anchor set (a multi-set).
 664  */
 665 static void rem_anchor_token(int token_type)
 666 {
 667         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 668         assert(token_anchor_set[token_type] != 0);
 669         --token_anchor_set[token_type];
 670 }
 671
 672 /**
 673  * Return true if the token type of the current token is
 674  * in the anchor set.
 675  */
 676 static bool at_anchor(void)
 677 {
 678         if (token.type < 0)
 679                 return false;
 680         return token_anchor_set[token.type];
 681 }
 682
 683 /**
 684  * Eat tokens until a matching token type is found.
 685  */
 686 static void eat_until_matching_token(int type)
 687 {
 688         int end_token;
 689         switch (type) {
 690                 case '(': end_token = ')';  break;
 691                 case '{': end_token = '}';  break;
 692                 case '[': end_token = ']';  break;
 693                 default:  end_token = type; break;
 694         }
 695
 696         unsigned parenthesis_count = 0;
 697         unsigned brace_count       = 0;
 698         unsigned bracket_count     = 0;
 699         while (token.type        != end_token ||
 700                parenthesis_count != 0         ||
 701                brace_count       != 0         ||
 702                bracket_count     != 0) {
 703                 switch (token.type) {
 704                 case T_EOF: return;
 705                 case '(': ++parenthesis_count; break;
 706                 case '{': ++brace_count;       break;
 707                 case '[': ++bracket_count;     break;
 708
 709                 case ')':
 710                         if (parenthesis_count > 0)
 711                                 --parenthesis_count;
 712                         goto check_stop;
 713
 714                 case '}':
 715                         if (brace_count > 0)
 716                                 --brace_count;
 717                         goto check_stop;
 718
 719                 case ']':
 720                         if (bracket_count > 0)
 721                                 --bracket_count;
 722 check_stop:
 723                         if (token.type        == end_token &&
 724                             parenthesis_count == 0         &&
 725                             brace_count       == 0         &&
 726                             bracket_count     == 0)
 727                                 return;
 728                         break;
 729
 730                 default:
 731                         break;
 732                 }
 733                 next_token();
 734         }
 735 }
 736
 737 /**
 738  * Eat input tokens until an anchor is found.
 739  */
 740 static void eat_until_anchor(void)
 741 {
 742         while (token_anchor_set[token.type] == 0) {
 743                 if (token.type == '(' || token.type == '{' || token.type == '[')
 744                         eat_until_matching_token(token.type);
 745                 next_token();
 746         }
 747 }
 748
 749 /**
 750  * Eat a whole block from input tokens.
 751  */
 752 static void eat_block(void)
 753 {
 754         eat_until_matching_token('{');
 755         if (token.type == '}')
 756                 next_token();
 757 }
 758
 759 #define eat(token_type)  do { assert(token.type == (token_type)); next_token(); } while (0)
 760
 761 /**
 762  * Report a parse error because an expected token was not found.
 763  */
 764 static
 765 #if defined __GNUC__ && __GNUC__ >= 4
 766 __attribute__((sentinel))
 767 #endif
 768 void parse_error_expected(const char *message, ...)
 769 {
 770         if (message != NULL) {
 771                 errorf(HERE, "%s", message);
 772         }
 773         va_list ap;
 774         va_start(ap, message);
 775         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 776         va_end(ap);
 777 }
 778
 779 /**
 780  * Report an incompatible type.
 781  */
 782 static void type_error_incompatible(const char *msg,
 783                 const source_position_t *source_position, type_t *type1, type_t *type2)
 784 {
 785         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 786                msg, type1, type2);
 787 }
 788
 789 /**
 790  * Expect the current token is the expected token.
 791  * If not, generate an error, eat the current statement,
 792  * and goto the end_error label.
 793  */
 794 #define expect(expected)                                  \
 795         do {                                                  \
 796                 if (UNLIKELY(token.type != (expected))) {         \
 797                         parse_error_expected(NULL, (expected), NULL); \
 798                         add_anchor_token(expected);                   \
 799                         eat_until_anchor();                           \
 800                         if (token.type == expected)                   \
 801                                 next_token();                             \
 802                         rem_anchor_token(expected);                   \
 803                         goto end_error;                               \
 804                 }                                                 \
 805                 next_token();                                     \
 806         } while (0)
 807
 808 /**
 809  * Push a given scope on the scope stack and make it the
 810  * current scope
 811  */
 812 static scope_t *scope_push(scope_t *new_scope)
 813 {
 814         if (current_scope != NULL) {
 815                 new_scope->depth = current_scope->depth + 1;
 816         }
 817
 818         scope_t *old_scope = current_scope;
 819         current_scope      = new_scope;
 820         return old_scope;
 821 }
 822
 823 /**
 824  * Pop the current scope from the scope stack.
 825  */
 826 static void scope_pop(scope_t *old_scope)
 827 {
 828         current_scope = old_scope;
 829 }
 830
 831 /**
 832  * Search an entity by its symbol in a given namespace.
 833  */
 834 static entity_t *get_entity(const symbol_t *const symbol,
 835                             namespace_tag_t namespc)
 836 {
 837         entity_t *entity = symbol->entity;
 838         for (; entity != NULL; entity = entity->base.symbol_next) {
 839                 if (entity->base.namespc == namespc)
 840                         return entity;
 841         }
 842
 843         return NULL;
 844 }
 845
 846 /**
 847  * pushs an entity on the environment stack and links the corresponding symbol
 848  * it.
 849  */
 850 static void stack_push(stack_entry_t **stack_ptr, entity_t *entity)
 851 {
 852         symbol_t           *symbol  = entity->base.symbol;
 853         entity_namespace_t  namespc = entity->base.namespc;
 854         assert(namespc != NAMESPACE_INVALID);
 855
 856         /* replace/add entity into entity list of the symbol */
 857         entity_t **anchor;
 858         entity_t  *iter;
 859         for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 860                 iter = *anchor;
 861                 if (iter == NULL)
 862                         break;
 863
 864                 /* replace an entry? */
 865                 if (iter->base.namespc == namespc) {
 866                         entity->base.symbol_next = iter->base.symbol_next;
 867                         break;
 868                 }
 869         }
 870         *anchor = entity;
 871
 872         /* remember old declaration */
 873         stack_entry_t entry;
 874         entry.symbol     = symbol;
 875         entry.old_entity = iter;
 876         entry.namespc    = namespc;
 877         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 878 }
 879
 880 /**
 881  * Push an entity on the environment stack.
 882  */
 883 static void environment_push(entity_t *entity)
 884 {
 885         assert(entity->base.source_position.input_name != NULL);
 886         assert(entity->base.parent_scope != NULL);
 887         stack_push(&environment_stack, entity);
 888 }
 889
 890 /**
 891  * Push a declaration on the global label stack.
 892  *
 893  * @param declaration  the declaration
 894  */
 895 static void label_push(entity_t *label)
 896 {
 897         /* we abuse the parameters scope as parent for the labels */
 898         label->base.parent_scope = &current_function->parameters;
 899         stack_push(&label_stack, label);
 900 }
 901
 902 /**
 903  * pops symbols from the environment stack until @p new_top is the top element
 904  */
 905 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 906 {
 907         stack_entry_t *stack = *stack_ptr;
 908         size_t         top   = ARR_LEN(stack);
 909         size_t         i;
 910
 911         assert(new_top <= top);
 912         if (new_top == top)
 913                 return;
 914
 915         for (i = top; i > new_top; --i) {
 916                 stack_entry_t *entry = &stack[i - 1];
 917
 918                 entity_t           *old_entity = entry->old_entity;
 919                 symbol_t           *symbol     = entry->symbol;
 920                 entity_namespace_t  namespc    = entry->namespc;
 921
 922                 /* replace with old_entity/remove */
 923                 entity_t **anchor;
 924                 entity_t  *iter;
 925                 for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 926                         iter = *anchor;
 927                         assert(iter != NULL);
 928                         /* replace an entry? */
 929                         if (iter->base.namespc == namespc)
 930                                 break;
 931                 }
 932
 933                 /* restore definition from outer scopes (if there was one) */
 934                 if (old_entity != NULL) {
 935                         old_entity->base.symbol_next = iter->base.symbol_next;
 936                         *anchor                      = old_entity;
 937                 } else {
 938                         /* remove entry from list */
 939                         *anchor = iter->base.symbol_next;
 940                 }
 941         }
 942
 943         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
 944 }
 945
 946 /**
 947  * Pop all entries from the environment stack until the new_top
 948  * is reached.
 949  *
 950  * @param new_top  the new stack top
 951  */
 952 static void environment_pop_to(size_t new_top)
 953 {
 954         stack_pop_to(&environment_stack, new_top);
 955 }
 956
 957 /**
 958  * Pop all entries from the global label stack until the new_top
 959  * is reached.
 960  *
 961  * @param new_top  the new stack top
 962  */
 963 static void label_pop_to(size_t new_top)
 964 {
 965         stack_pop_to(&label_stack, new_top);
 966 }
 967
 968 static int get_akind_rank(atomic_type_kind_t akind)
 969 {
 970         return (int) akind;
 971 }
 972
 973 /**
 974  * Return the type rank for an atomic type.
 975  */
 976 static int get_rank(const type_t *type)
 977 {
 978         assert(!is_typeref(type));
 979         /* The C-standard allows promoting enums to int or unsigned int (see § 7.2.2
 980          * and esp. footnote 108). However we can't fold constants (yet), so we
 981          * can't decide whether unsigned int is possible, while int always works.
 982          * (unsigned int would be preferable when possible... for stuff like
 983          *  struct { enum { ... } bla : 4; } ) */
 984         if (type->kind == TYPE_ENUM)
 985                 return get_akind_rank(ATOMIC_TYPE_INT);
 986
 987         assert(type->kind == TYPE_ATOMIC);
 988         return get_akind_rank(type->atomic.akind);
 989 }
 990
 991 /**
 992  * Do integer promotion for a given type.
 993  *
 994  * @param type  the type to promote
 995  * @return the promoted type
 996  */
 997 static type_t *promote_integer(type_t *type)
 998 {
 999         if (type->kind == TYPE_BITFIELD)
1000                 type = type->bitfield.base_type;
1001
1002         if (get_rank(type) < get_akind_rank(ATOMIC_TYPE_INT))
1003                 type = type_int;
1004
1005         return type;
1006 }
1007
1008 /**
1009  * Create a cast expression.
1010  *
1011  * @param expression  the expression to cast
1012  * @param dest_type   the destination type
1013  */
1014 static expression_t *create_cast_expression(expression_t *expression,
1015                                             type_t *dest_type)
1016 {
1017         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
1018
1019         cast->unary.value = expression;
1020         cast->base.type   = dest_type;
1021
1022         return cast;
1023 }
1024
1025 /**
1026  * Check if a given expression represents a null pointer constant.
1027  *
1028  * @param expression  the expression to check
1029  */
1030 static bool is_null_pointer_constant(const expression_t *expression)
1031 {
1032         /* skip void* cast */
1033         if (expression->kind == EXPR_UNARY_CAST
1034                         || expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
1035                 expression = expression->unary.value;
1036         }
1037
1038         /* TODO: not correct yet, should be any constant integer expression
1039          * which evaluates to 0 */
1040         if (expression->kind != EXPR_CONST)
1041                 return false;
1042
1043         type_t *const type = skip_typeref(expression->base.type);
1044         if (!is_type_integer(type))
1045                 return false;
1046
1047         return expression->conste.v.int_value == 0;
1048 }
1049
1050 /**
1051  * Create an implicit cast expression.
1052  *
1053  * @param expression  the expression to cast
1054  * @param dest_type   the destination type
1055  */
1056 static expression_t *create_implicit_cast(expression_t *expression,
1057                                           type_t *dest_type)
1058 {
1059         type_t *const source_type = expression->base.type;
1060
1061         if (source_type == dest_type)
1062                 return expression;
1063
1064         return create_cast_expression(expression, dest_type);
1065 }
1066
1067 typedef enum assign_error_t {
1068         ASSIGN_SUCCESS,
1069         ASSIGN_ERROR_INCOMPATIBLE,
1070         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
1071         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
1072         ASSIGN_WARNING_POINTER_FROM_INT,
1073         ASSIGN_WARNING_INT_FROM_POINTER
1074 } assign_error_t;
1075
1076 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
1077                                 const expression_t *const right,
1078                                 const char *context,
1079                                 const source_position_t *source_position)
1080 {
1081         type_t *const orig_type_right = right->base.type;
1082         type_t *const type_left       = skip_typeref(orig_type_left);
1083         type_t *const type_right      = skip_typeref(orig_type_right);
1084
1085         switch (error) {
1086         case ASSIGN_SUCCESS:
1087                 return;
1088         case ASSIGN_ERROR_INCOMPATIBLE:
1089                 errorf(source_position,
1090                        "destination type '%T' in %s is incompatible with type '%T'",
1091                        orig_type_left, context, orig_type_right);
1092                 return;
1093
1094         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
1095                 if (warning.other) {
1096                         type_t *points_to_left  = skip_typeref(type_left->pointer.points_to);
1097                         type_t *points_to_right = skip_typeref(type_right->pointer.points_to);
1098
1099                         /* the left type has all qualifiers from the right type */
1100                         unsigned missing_qualifiers
1101                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1102                         warningf(source_position,
1103                                         "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
1104                                         orig_type_left, context, orig_type_right, missing_qualifiers);
1105                 }
1106                 return;
1107         }
1108
1109         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
1110                 if (warning.other) {
1111                         warningf(source_position,
1112                                         "destination type '%T' in %s is incompatible with '%E' of type '%T'",
1113                                         orig_type_left, context, right, orig_type_right);
1114                 }
1115                 return;
1116
1117         case ASSIGN_WARNING_POINTER_FROM_INT:
1118                 if (warning.other) {
1119                         warningf(source_position,
1120                                         "%s makes pointer '%T' from integer '%T' without a cast",
1121                                         context, orig_type_left, orig_type_right);
1122                 }
1123                 return;
1124
1125         case ASSIGN_WARNING_INT_FROM_POINTER:
1126                 if (warning.other) {
1127                         warningf(source_position,
1128                                         "%s makes integer '%T' from pointer '%T' without a cast",
1129                                         context, orig_type_left, orig_type_right);
1130                 }
1131                 return;
1132
1133         default:
1134                 panic("invalid error value");
1135         }
1136 }
1137
1138 /** Implements the rules from § 6.5.16.1 */
1139 static assign_error_t semantic_assign(type_t *orig_type_left,
1140                                       const expression_t *const right)
1141 {
1142         type_t *const orig_type_right = right->base.type;
1143         type_t *const type_left       = skip_typeref(orig_type_left);
1144         type_t *const type_right      = skip_typeref(orig_type_right);
1145
1146         if (is_type_pointer(type_left)) {
1147                 if (is_null_pointer_constant(right)) {
1148                         return ASSIGN_SUCCESS;
1149                 } else if (is_type_pointer(type_right)) {
1150                         type_t *points_to_left
1151                                 = skip_typeref(type_left->pointer.points_to);
1152                         type_t *points_to_right
1153                                 = skip_typeref(type_right->pointer.points_to);
1154                         assign_error_t res = ASSIGN_SUCCESS;
1155
1156                         /* the left type has all qualifiers from the right type */
1157                         unsigned missing_qualifiers
1158                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1159                         if (missing_qualifiers != 0) {
1160                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1161                         }
1162
1163                         points_to_left  = get_unqualified_type(points_to_left);
1164                         points_to_right = get_unqualified_type(points_to_right);
1165
1166                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID))
1167                                 return res;
1168
1169                         if (is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1170                                 /* ISO/IEC 14882:1998(E) §C.1.2:6 */
1171                                 return c_mode & _CXX ? ASSIGN_ERROR_INCOMPATIBLE : res;
1172                         }
1173
1174                         if (!types_compatible(points_to_left, points_to_right)) {
1175                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1176                         }
1177
1178                         return res;
1179                 } else if (is_type_integer(type_right)) {
1180                         return ASSIGN_WARNING_POINTER_FROM_INT;
1181                 }
1182         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1183             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1184                 && is_type_pointer(type_right))) {
1185                 return ASSIGN_SUCCESS;
1186         } else if ((is_type_compound(type_left)  && is_type_compound(type_right))
1187                         || (is_type_builtin(type_left) && is_type_builtin(type_right))) {
1188                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1189                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1190                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1191                         return ASSIGN_SUCCESS;
1192                 }
1193         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1194                 return ASSIGN_WARNING_INT_FROM_POINTER;
1195         }
1196
1197         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1198                 return ASSIGN_SUCCESS;
1199
1200         return ASSIGN_ERROR_INCOMPATIBLE;
1201 }
1202
1203 static expression_t *parse_constant_expression(void)
1204 {
1205         expression_t *result = parse_sub_expression(PREC_CONDITIONAL);
1206
1207         if (!is_constant_expression(result)) {
1208                 errorf(&result->base.source_position,
1209                        "expression '%E' is not constant", result);
1210         }
1211
1212         return result;
1213 }
1214
1215 static expression_t *parse_assignment_expression(void)
1216 {
1217         return parse_sub_expression(PREC_ASSIGNMENT);
1218 }
1219
1220 static string_t parse_string_literals(void)
1221 {
1222         assert(token.type == T_STRING_LITERAL);
1223         string_t result = token.v.string;
1224
1225         next_token();
1226
1227         while (token.type == T_STRING_LITERAL) {
1228                 result = concat_strings(&result, &token.v.string);
1229                 next_token();
1230         }
1231
1232         return result;
1233 }
1234
1235 static const char *const gnu_attribute_names[GNU_AK_LAST] = {
1236         [GNU_AK_CONST]                  = "const",
1237         [GNU_AK_VOLATILE]               = "volatile",
1238         [GNU_AK_CDECL]                  = "cdecl",
1239         [GNU_AK_STDCALL]                = "stdcall",
1240         [GNU_AK_FASTCALL]               = "fastcall",
1241         [GNU_AK_DEPRECATED]             = "deprecated",
1242         [GNU_AK_NOINLINE]               = "noinline",
1243         [GNU_AK_NORETURN]               = "noreturn",
1244         [GNU_AK_NAKED]                  = "naked",
1245         [GNU_AK_PURE]                   = "pure",
1246         [GNU_AK_ALWAYS_INLINE]          = "always_inline",
1247         [GNU_AK_MALLOC]                 = "malloc",
1248         [GNU_AK_WEAK]                   = "weak",
1249         [GNU_AK_CONSTRUCTOR]            = "constructor",
1250         [GNU_AK_DESTRUCTOR]             = "destructor",
1251         [GNU_AK_NOTHROW]                = "nothrow",
1252         [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
1253         [GNU_AK_COMMON]                 = "common",
1254         [GNU_AK_NOCOMMON]               = "nocommon",
1255         [GNU_AK_PACKED]                 = "packed",
1256         [GNU_AK_SHARED]                 = "shared",
1257         [GNU_AK_NOTSHARED]              = "notshared",
1258         [GNU_AK_USED]                   = "used",
1259         [GNU_AK_UNUSED]                 = "unused",
1260         [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
1261         [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
1262         [GNU_AK_LONGCALL]               = "longcall",
1263         [GNU_AK_SHORTCALL]              = "shortcall",
1264         [GNU_AK_LONG_CALL]              = "long_call",
1265         [GNU_AK_SHORT_CALL]             = "short_call",
1266         [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
1267         [GNU_AK_INTERRUPT]              = "interrupt",
1268         [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
1269         [GNU_AK_NMI_HANDLER]            = "nmi_handler",
1270         [GNU_AK_NESTING]                = "nesting",
1271         [GNU_AK_NEAR]                   = "near",
1272         [GNU_AK_FAR]                    = "far",
1273         [GNU_AK_SIGNAL]                 = "signal",
1274         [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
1275         [GNU_AK_TINY_DATA]              = "tiny_data",
1276         [GNU_AK_SAVEALL]                = "saveall",
1277         [GNU_AK_FLATTEN]                = "flatten",
1278         [GNU_AK_SSEREGPARM]             = "sseregparm",
1279         [GNU_AK_EXTERNALLY_VISIBLE]     = "externally_visible",
1280         [GNU_AK_RETURN_TWICE]           = "return_twice",
1281         [GNU_AK_MAY_ALIAS]              = "may_alias",
1282         [GNU_AK_MS_STRUCT]              = "ms_struct",
1283         [GNU_AK_GCC_STRUCT]             = "gcc_struct",
1284         [GNU_AK_DLLIMPORT]              = "dllimport",
1285         [GNU_AK_DLLEXPORT]              = "dllexport",
1286         [GNU_AK_ALIGNED]                = "aligned",
1287         [GNU_AK_ALIAS]                  = "alias",
1288         [GNU_AK_SECTION]                = "section",
1289         [GNU_AK_FORMAT]                 = "format",
1290         [GNU_AK_FORMAT_ARG]             = "format_arg",
1291         [GNU_AK_WEAKREF]                = "weakref",
1292         [GNU_AK_NONNULL]                = "nonnull",
1293         [GNU_AK_TLS_MODEL]              = "tls_model",
1294         [GNU_AK_VISIBILITY]             = "visibility",
1295         [GNU_AK_REGPARM]                = "regparm",
1296         [GNU_AK_MODE]                   = "mode",
1297         [GNU_AK_MODEL]                  = "model",
1298         [GNU_AK_TRAP_EXIT]              = "trap_exit",
1299         [GNU_AK_SP_SWITCH]              = "sp_switch",
1300         [GNU_AK_SENTINEL]               = "sentinel"
1301 };
1302
1303 /**
1304  * compare two string, ignoring double underscores on the second.
1305  */
1306 static int strcmp_underscore(const char *s1, const char *s2)
1307 {
1308         if (s2[0] == '_' && s2[1] == '_') {
1309                 size_t len2 = strlen(s2);
1310                 size_t len1 = strlen(s1);
1311                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1312                         return strncmp(s1, s2+2, len2-4);
1313                 }
1314         }
1315
1316         return strcmp(s1, s2);
1317 }
1318
1319 /**
1320  * Allocate a new gnu temporal attribute of given kind.
1321  */
1322 static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
1323 {
1324         gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
1325         attribute->kind            = kind;
1326         attribute->next            = NULL;
1327         attribute->invalid         = false;
1328         attribute->have_arguments  = false;
1329
1330         return attribute;
1331 }
1332
1333 /**
1334  * Parse one constant expression argument of the given attribute.
1335  */
1336 static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
1337 {
1338         expression_t *expression;
1339         add_anchor_token(')');
1340         expression = parse_constant_expression();
1341         rem_anchor_token(')');
1342         expect(')');
1343         attribute->u.argument = fold_constant(expression);
1344         return;
1345 end_error:
1346         attribute->invalid = true;
1347 }
1348
1349 /**
1350  * Parse a list of constant expressions arguments of the given attribute.
1351  */
1352 static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
1353 {
1354         argument_list_t **list = &attribute->u.arguments;
1355         argument_list_t  *entry;
1356         expression_t     *expression;
1357         add_anchor_token(')');
1358         add_anchor_token(',');
1359         while (true) {
1360                 expression = parse_constant_expression();
1361                 entry = obstack_alloc(&temp_obst, sizeof(entry));
1362                 entry->argument = fold_constant(expression);
1363                 entry->next     = NULL;
1364                 *list = entry;
1365                 list = &entry->next;
1366                 if (token.type != ',')
1367                         break;
1368                 next_token();
1369         }
1370         rem_anchor_token(',');
1371         rem_anchor_token(')');
1372         expect(')');
1373         return;
1374 end_error:
1375         attribute->invalid = true;
1376 }
1377
1378 /**
1379  * Parse one string literal argument of the given attribute.
1380  */
1381 static void parse_gnu_attribute_string_arg(gnu_attribute_t *attribute,
1382                                            string_t *string)
1383 {
1384         add_anchor_token('(');
1385         if (token.type != T_STRING_LITERAL) {
1386                 parse_error_expected("while parsing attribute directive",
1387                                      T_STRING_LITERAL, NULL);
1388                 goto end_error;
1389         }
1390         *string = parse_string_literals();
1391         rem_anchor_token('(');
1392         expect(')');
1393         return;
1394 end_error:
1395         attribute->invalid = true;
1396 }
1397
1398 /**
1399  * Parse one tls model of the given attribute.
1400  */
1401 static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
1402 {
1403         static const char *const tls_models[] = {
1404                 "global-dynamic",
1405                 "local-dynamic",
1406                 "initial-exec",
1407                 "local-exec"
1408         };
1409         string_t string = { NULL, 0 };
1410         parse_gnu_attribute_string_arg(attribute, &string);
1411         if (string.begin != NULL) {
1412                 for (size_t i = 0; i < 4; ++i) {
1413                         if (strcmp(tls_models[i], string.begin) == 0) {
1414                                 attribute->u.value = i;
1415                                 return;
1416                         }
1417                 }
1418                 errorf(HERE, "'%s' is an unrecognized tls model", string.begin);
1419         }
1420         attribute->invalid = true;
1421 }
1422
1423 /**
1424  * Parse one tls model of the given attribute.
1425  */
1426 static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
1427 {
1428         static const char *const visibilities[] = {
1429                 "default",
1430                 "protected",
1431                 "hidden",
1432                 "internal"
1433         };
1434         string_t string = { NULL, 0 };
1435         parse_gnu_attribute_string_arg(attribute, &string);
1436         if (string.begin != NULL) {
1437                 for (size_t i = 0; i < 4; ++i) {
1438                         if (strcmp(visibilities[i], string.begin) == 0) {
1439                                 attribute->u.value = i;
1440                                 return;
1441                         }
1442                 }
1443                 errorf(HERE, "'%s' is an unrecognized visibility", string.begin);
1444         }
1445         attribute->invalid = true;
1446 }
1447
1448 /**
1449  * Parse one (code) model of the given attribute.
1450  */
1451 static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
1452 {
1453         static const char *const visibilities[] = {
1454                 "small",
1455                 "medium",
1456                 "large"
1457         };
1458         string_t string = { NULL, 0 };
1459         parse_gnu_attribute_string_arg(attribute, &string);
1460         if (string.begin != NULL) {
1461                 for (int i = 0; i < 3; ++i) {
1462                         if (strcmp(visibilities[i], string.begin) == 0) {
1463                                 attribute->u.value = i;
1464                                 return;
1465                         }
1466                 }
1467                 errorf(HERE, "'%s' is an unrecognized model", string.begin);
1468         }
1469         attribute->invalid = true;
1470 }
1471
1472 /**
1473  * Parse one mode of the given attribute.
1474  */
1475 static void parse_gnu_attribute_mode_arg(gnu_attribute_t *attribute)
1476 {
1477         /* TODO: find out what is allowed here... */
1478
1479         /* at least: byte, word, pointer, list of machine modes
1480          * __XXX___ is interpreted as XXX */
1481         add_anchor_token(')');
1482
1483         if (token.type != T_IDENTIFIER) {
1484                 expect(T_IDENTIFIER);
1485         }
1486
1487         /* This isn't really correct, the backend should provide a list of machine
1488          * specific modes (according to gcc philosophy that is...) */
1489         const char *symbol_str = token.v.symbol->string;
1490         if (strcmp_underscore("QI",   symbol_str) == 0 ||
1491             strcmp_underscore("byte", symbol_str) == 0) {
1492                 attribute->u.akind = ATOMIC_TYPE_CHAR;
1493         } else if (strcmp_underscore("HI", symbol_str) == 0) {
1494                 attribute->u.akind = ATOMIC_TYPE_SHORT;
1495         } else if (strcmp_underscore("SI",      symbol_str) == 0
1496                 || strcmp_underscore("word",    symbol_str) == 0
1497                 || strcmp_underscore("pointer", symbol_str) == 0) {
1498                 attribute->u.akind = ATOMIC_TYPE_INT;
1499         } else if (strcmp_underscore("DI", symbol_str) == 0) {
1500                 attribute->u.akind = ATOMIC_TYPE_LONGLONG;
1501         } else {
1502                 if (warning.other)
1503                         warningf(HERE, "ignoring unknown mode '%s'", symbol_str);
1504                 attribute->invalid = true;
1505         }
1506         next_token();
1507
1508         rem_anchor_token(')');
1509         expect(')');
1510         return;
1511 end_error:
1512         attribute->invalid = true;
1513 }
1514
1515 /**
1516  * Parse one interrupt argument of the given attribute.
1517  */
1518 static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
1519 {
1520         static const char *const interrupts[] = {
1521                 "IRQ",
1522                 "FIQ",
1523                 "SWI",
1524                 "ABORT",
1525                 "UNDEF"
1526         };
1527         string_t string = { NULL, 0 };
1528         parse_gnu_attribute_string_arg(attribute, &string);
1529         if (string.begin != NULL) {
1530                 for (size_t i = 0; i < 5; ++i) {
1531                         if (strcmp(interrupts[i], string.begin) == 0) {
1532                                 attribute->u.value = i;
1533                                 return;
1534                         }
1535                 }
1536                 errorf(HERE, "'%s' is not an interrupt", string.begin);
1537         }
1538         attribute->invalid = true;
1539 }
1540
1541 /**
1542  * Parse ( identifier, const expression, const expression )
1543  */
1544 static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
1545 {
1546         static const char *const format_names[] = {
1547                 "printf",
1548                 "scanf",
1549                 "strftime",
1550                 "strfmon"
1551         };
1552         int i;
1553
1554         if (token.type != T_IDENTIFIER) {
1555                 parse_error_expected("while parsing format attribute directive", T_IDENTIFIER, NULL);
1556                 goto end_error;
1557         }
1558         const char *name = token.v.symbol->string;
1559         for (i = 0; i < 4; ++i) {
1560                 if (strcmp_underscore(format_names[i], name) == 0)
1561                         break;
1562         }
1563         if (i >= 4) {
1564                 if (warning.attribute)
1565                         warningf(HERE, "'%s' is an unrecognized format function type", name);
1566         }
1567         next_token();
1568
1569         expect(',');
1570         add_anchor_token(')');
1571         add_anchor_token(',');
1572         parse_constant_expression();
1573         rem_anchor_token(',');
1574         rem_anchor_token(')');
1575
1576         expect(',');
1577         add_anchor_token(')');
1578         parse_constant_expression();
1579         rem_anchor_token(')');
1580         expect(')');
1581         return;
1582 end_error:
1583         attribute->u.value = true;
1584 }
1585
1586 /**
1587  * Check that a given GNU attribute has no arguments.
1588  */
1589 static void check_no_argument(gnu_attribute_t *attribute, const char *name)
1590 {
1591         if (!attribute->have_arguments)
1592                 return;
1593
1594         /* should have no arguments */
1595         errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1596         eat_until_matching_token('(');
1597         /* we have already consumed '(', so we stop before ')', eat it */
1598         eat(')');
1599         attribute->invalid = true;
1600 }
1601
1602 /**
1603  * Parse one GNU attribute.
1604  *
1605  * Note that attribute names can be specified WITH or WITHOUT
1606  * double underscores, ie const or __const__.
1607  *
1608  * The following attributes are parsed without arguments
1609  *  const
1610  *  volatile
1611  *  cdecl
1612  *  stdcall
1613  *  fastcall
1614  *  deprecated
1615  *  noinline
1616  *  noreturn
1617  *  naked
1618  *  pure
1619  *  always_inline
1620  *  malloc
1621  *  weak
1622  *  constructor
1623  *  destructor
1624  *  nothrow
1625  *  transparent_union
1626  *  common
1627  *  nocommon
1628  *  packed
1629  *  shared
1630  *  notshared
1631  *  used
1632  *  unused
1633  *  no_instrument_function
1634  *  warn_unused_result
1635  *  longcall
1636  *  shortcall
1637  *  long_call
1638  *  short_call
1639  *  function_vector
1640  *  interrupt_handler
1641  *  nmi_handler
1642  *  nesting
1643  *  near
1644  *  far
1645  *  signal
1646  *  eightbit_data
1647  *  tiny_data
1648  *  saveall
1649  *  flatten
1650  *  sseregparm
1651  *  externally_visible
1652  *  return_twice
1653  *  may_alias
1654  *  ms_struct
1655  *  gcc_struct
1656  *  dllimport
1657  *  dllexport
1658  *
1659  * The following attributes are parsed with arguments
1660  *  aligned( const expression )
1661  *  alias( string literal )
1662  *  section( string literal )
1663  *  format( identifier, const expression, const expression )
1664  *  format_arg( const expression )
1665  *  tls_model( string literal )
1666  *  visibility( string literal )
1667  *  regparm( const expression )
1668  *  model( string leteral )
1669  *  trap_exit( const expression )
1670  *  sp_switch( string literal )
1671  *
1672  * The following attributes might have arguments
1673  *  weak_ref( string literal )
1674  *  non_null( const expression // ',' )
1675  *  interrupt( string literal )
1676  *  sentinel( constant expression )
1677  */
1678 static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
1679 {
1680         gnu_attribute_t *head      = *attributes;
1681         gnu_attribute_t *last      = *attributes;
1682         decl_modifiers_t modifiers = 0;
1683         gnu_attribute_t *attribute;
1684
1685         eat(T___attribute__);
1686         expect('(');
1687         expect('(');
1688
1689         if (token.type != ')') {
1690                 /* find the end of the list */
1691                 if (last != NULL) {
1692                         while (last->next != NULL)
1693                                 last = last->next;
1694                 }
1695
1696                 /* non-empty attribute list */
1697                 while (true) {
1698                         const char *name;
1699                         if (token.type == T_const) {
1700                                 name = "const";
1701                         } else if (token.type == T_volatile) {
1702                                 name = "volatile";
1703                         } else if (token.type == T_cdecl) {
1704                                 /* __attribute__((cdecl)), WITH ms mode */
1705                                 name = "cdecl";
1706                         } else if (token.type == T_IDENTIFIER) {
1707                                 const symbol_t *sym = token.v.symbol;
1708                                 name = sym->string;
1709                         } else {
1710                                 parse_error_expected("while parsing GNU attribute", T_IDENTIFIER, NULL);
1711                                 break;
1712                         }
1713
1714                         next_token();
1715
1716                         int i;
1717                         for (i = 0; i < GNU_AK_LAST; ++i) {
1718                                 if (strcmp_underscore(gnu_attribute_names[i], name) == 0)
1719                                         break;
1720                         }
1721                         gnu_attribute_kind_t kind = (gnu_attribute_kind_t)i;
1722
1723                         attribute = NULL;
1724                         if (kind == GNU_AK_LAST) {
1725                                 if (warning.attribute)
1726                                         warningf(HERE, "'%s' attribute directive ignored", name);
1727
1728                                 /* skip possible arguments */
1729                                 if (token.type == '(') {
1730                                         eat_until_matching_token(')');
1731                                 }
1732                         } else {
1733                                 /* check for arguments */
1734                                 attribute = allocate_gnu_attribute(kind);
1735                                 if (token.type == '(') {
1736                                         next_token();
1737                                         if (token.type == ')') {
1738                                                 /* empty args are allowed */
1739                                                 next_token();
1740                                         } else
1741                                                 attribute->have_arguments = true;
1742                                 }
1743
1744                                 switch (kind) {
1745                                 case GNU_AK_VOLATILE:
1746                                 case GNU_AK_NAKED:
1747                                 case GNU_AK_MALLOC:
1748                                 case GNU_AK_WEAK:
1749                                 case GNU_AK_COMMON:
1750                                 case GNU_AK_NOCOMMON:
1751                                 case GNU_AK_SHARED:
1752                                 case GNU_AK_NOTSHARED:
1753                                 case GNU_AK_NO_INSTRUMENT_FUNCTION:
1754                                 case GNU_AK_WARN_UNUSED_RESULT:
1755                                 case GNU_AK_LONGCALL:
1756                                 case GNU_AK_SHORTCALL:
1757                                 case GNU_AK_LONG_CALL:
1758                                 case GNU_AK_SHORT_CALL:
1759                                 case GNU_AK_FUNCTION_VECTOR:
1760                                 case GNU_AK_INTERRUPT_HANDLER:
1761                                 case GNU_AK_NMI_HANDLER:
1762                                 case GNU_AK_NESTING:
1763                                 case GNU_AK_NEAR:
1764                                 case GNU_AK_FAR:
1765                                 case GNU_AK_SIGNAL:
1766                                 case GNU_AK_EIGTHBIT_DATA:
1767                                 case GNU_AK_TINY_DATA:
1768                                 case GNU_AK_SAVEALL:
1769                                 case GNU_AK_FLATTEN:
1770                                 case GNU_AK_SSEREGPARM:
1771                                 case GNU_AK_EXTERNALLY_VISIBLE:
1772                                 case GNU_AK_RETURN_TWICE:
1773                                 case GNU_AK_MAY_ALIAS:
1774                                 case GNU_AK_MS_STRUCT:
1775                                 case GNU_AK_GCC_STRUCT:
1776                                         goto no_arg;
1777
1778                                 case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
1779                                 case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
1780                                 case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
1781                                 case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
1782                                 case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
1783                                 case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
1784                                 case GNU_AK_CONST:             modifiers |= DM_CONST;             goto no_arg;
1785                                 case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
1786                                 case GNU_AK_DLLIMPORT:         modifiers |= DM_DLLIMPORT;         goto no_arg;
1787                                 case GNU_AK_DLLEXPORT:         modifiers |= DM_DLLEXPORT;         goto no_arg;
1788                                 case GNU_AK_PACKED:            modifiers |= DM_PACKED;            goto no_arg;
1789                                 case GNU_AK_NOINLINE:          modifiers |= DM_NOINLINE;          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(')');
1904         expect(')');
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('(');
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(')');
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(']');
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('=');
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('}');
2777                                 } else {
2778                                         expect('}');
2779                                         goto error_parse_next;
2780                                 }
2781                         }
2782                 } else {
2783                         /* must be an expression */
2784                         expression_t *expression = parse_assignment_expression();
2785
2786                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2787                                 errorf(&expression->base.source_position,
2788                                        "Initialisation expression '%E' is not constant",
2789                                        expression);
2790                         }
2791
2792                         if (type == NULL) {
2793                                 /* we are already outside, ... */
2794                                 type_t *const outer_type_skip = skip_typeref(outer_type);
2795                                 if (is_type_compound(outer_type_skip) &&
2796                                     !outer_type_skip->compound.compound->complete) {
2797                                         goto error_parse_next;
2798                                 }
2799                                 goto error_excess;
2800                         }
2801
2802                         /* handle { "string" } special case */
2803                         if ((expression->kind == EXPR_STRING_LITERAL
2804                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2805                                         && outer_type != NULL) {
2806                                 sub = initializer_from_expression(outer_type, expression);
2807                                 if (sub != NULL) {
2808                                         if (token.type == ',') {
2809                                                 next_token();
2810                                         }
2811                                         if (token.type != '}' && warning.other) {
2812                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2813                                                                  orig_type);
2814                                         }
2815                                         /* TODO: eat , ... */
2816                                         return sub;
2817                                 }
2818                         }
2819
2820                         /* descend into subtypes until expression matches type */
2821                         while (true) {
2822                                 orig_type = path->top_type;
2823                                 type      = skip_typeref(orig_type);
2824
2825                                 sub = initializer_from_expression(orig_type, expression);
2826                                 if (sub != NULL) {
2827                                         break;
2828                                 }
2829                                 if (!is_type_valid(type)) {
2830                                         goto end_error;
2831                                 }
2832                                 if (is_type_scalar(type)) {
2833                                         errorf(&expression->base.source_position,
2834                                                         "expression '%E' doesn't match expected type '%T'",
2835                                                         expression, orig_type);
2836                                         goto end_error;
2837                                 }
2838
2839                                 descend_into_subtype(path);
2840                         }
2841                 }
2842
2843                 /* update largest index of top array */
2844                 const type_path_entry_t *first      = &path->path[0];
2845                 type_t                  *first_type = first->type;
2846                 first_type                          = skip_typeref(first_type);
2847                 if (is_type_array(first_type)) {
2848                         size_t index = first->v.index;
2849                         if (index > path->max_index)
2850                                 path->max_index = index;
2851                 }
2852
2853                 if (type != NULL) {
2854                         /* append to initializers list */
2855                         ARR_APP1(initializer_t*, initializers, sub);
2856                 } else {
2857 error_excess:
2858                         if (warning.other) {
2859                                 if (env->entity != NULL) {
2860                                         warningf(HERE, "excess elements in struct initializer for '%Y'",
2861                                            env->entity->base.symbol);
2862                                 } else {
2863                                         warningf(HERE, "excess elements in struct initializer");
2864                                 }
2865                         }
2866                 }
2867
2868 error_parse_next:
2869                 if (token.type == '}') {
2870                         break;
2871                 }
2872                 expect(',');
2873                 if (token.type == '}') {
2874                         break;
2875                 }
2876
2877                 if (type != NULL) {
2878                         /* advance to the next declaration if we are not at the end */
2879                         advance_current_object(path, top_path_level);
2880                         orig_type = path->top_type;
2881                         if (orig_type != NULL)
2882                                 type = skip_typeref(orig_type);
2883                         else
2884                                 type = NULL;
2885                 }
2886         }
2887
2888         size_t len  = ARR_LEN(initializers);
2889         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2890         initializer_t *result = allocate_ast_zero(size);
2891         result->kind          = INITIALIZER_LIST;
2892         result->list.len      = len;
2893         memcpy(&result->list.initializers, initializers,
2894                len * sizeof(initializers[0]));
2895
2896         DEL_ARR_F(initializers);
2897         ascend_to(path, top_path_level+1);
2898
2899         return result;
2900
2901 end_error:
2902         skip_initializers();
2903         DEL_ARR_F(initializers);
2904         ascend_to(path, top_path_level+1);
2905         return NULL;
2906 }
2907
2908 /**
2909  * Parses an initializer. Parsers either a compound literal
2910  * (env->declaration == NULL) or an initializer of a declaration.
2911  */
2912 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2913 {
2914         type_t        *type   = skip_typeref(env->type);
2915         initializer_t *result = NULL;
2916         size_t         max_index;
2917
2918         if (is_type_scalar(type)) {
2919                 result = parse_scalar_initializer(type, env->must_be_constant);
2920         } else if (token.type == '{') {
2921                 eat('{');
2922
2923                 type_path_t path;
2924                 memset(&path, 0, sizeof(path));
2925                 path.top_type = env->type;
2926                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2927
2928                 descend_into_subtype(&path);
2929
2930                 add_anchor_token('}');
2931                 result = parse_sub_initializer(&path, env->type, 1, env);
2932                 rem_anchor_token('}');
2933
2934                 max_index = path.max_index;
2935                 DEL_ARR_F(path.path);
2936
2937                 expect('}');
2938         } else {
2939                 /* parse_scalar_initializer() also works in this case: we simply
2940                  * have an expression without {} around it */
2941                 result = parse_scalar_initializer(type, env->must_be_constant);
2942         }
2943
2944         /* § 6.7.8 (22) array initializers for arrays with unknown size determine
2945          * the array type size */
2946         if (is_type_array(type) && type->array.size_expression == NULL
2947                         && result != NULL) {
2948                 size_t size;
2949                 switch (result->kind) {
2950                 case INITIALIZER_LIST:
2951                         size = max_index + 1;
2952                         break;
2953
2954                 case INITIALIZER_STRING:
2955                         size = result->string.string.size;
2956                         break;
2957
2958                 case INITIALIZER_WIDE_STRING:
2959                         size = result->wide_string.string.size;
2960                         break;
2961
2962                 case INITIALIZER_DESIGNATOR:
2963                 case INITIALIZER_VALUE:
2964                         /* can happen for parse errors */
2965                         size = 0;
2966                         break;
2967
2968                 default:
2969                         internal_errorf(HERE, "invalid initializer type");
2970                 }
2971
2972                 expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2973                 cnst->base.type          = type_size_t;
2974                 cnst->conste.v.int_value = size;
2975
2976                 type_t *new_type = duplicate_type(type);
2977
2978                 new_type->array.size_expression   = cnst;
2979                 new_type->array.size_constant     = true;
2980                 new_type->array.has_implicit_size = true;
2981                 new_type->array.size              = size;
2982                 env->type = new_type;
2983         }
2984
2985         return result;
2986 end_error:
2987         return NULL;
2988 }
2989
2990 static void append_entity(scope_t *scope, entity_t *entity)
2991 {
2992         if (scope->last_entity != NULL) {
2993                 scope->last_entity->base.next = entity;
2994         } else {
2995                 scope->entities = entity;
2996         }
2997         scope->last_entity = entity;
2998 }
2999
3000
3001 static compound_t *parse_compound_type_specifier(bool is_struct)
3002 {
3003         gnu_attribute_t  *attributes = NULL;
3004         decl_modifiers_t  modifiers  = 0;
3005         if (is_struct) {
3006                 eat(T_struct);
3007         } else {
3008                 eat(T_union);
3009         }
3010
3011         symbol_t   *symbol   = NULL;
3012         compound_t *compound = NULL;
3013
3014         if (token.type == T___attribute__) {
3015                 modifiers |= parse_attributes(&attributes);
3016         }
3017
3018         if (token.type == T_IDENTIFIER) {
3019                 symbol = token.v.symbol;
3020                 next_token();
3021
3022                 namespace_tag_t const namespc =
3023                         is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION;
3024                 entity_t *entity = get_entity(symbol, namespc);
3025                 if (entity != NULL) {
3026                         assert(entity->kind == (is_struct ? ENTITY_STRUCT : ENTITY_UNION));
3027                         compound = &entity->compound;
3028                         if (compound->base.parent_scope != current_scope &&
3029                             (token.type == '{' || token.type == ';')) {
3030                                 /* we're in an inner scope and have a definition. Override
3031                                    existing definition in outer scope */
3032                                 compound = NULL;
3033                         } else if (compound->complete && token.type == '{') {
3034                                 assert(symbol != NULL);
3035                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition %P)",
3036                                        is_struct ? "struct" : "union", symbol,
3037                                        &compound->base.source_position);
3038                                 /* clear members in the hope to avoid further errors */
3039                                 compound->members.entities = NULL;
3040                         }
3041                 }
3042         } else if (token.type != '{') {
3043                 if (is_struct) {
3044                         parse_error_expected("while parsing struct type specifier",
3045                                              T_IDENTIFIER, '{', NULL);
3046                 } else {
3047                         parse_error_expected("while parsing union type specifier",
3048                                              T_IDENTIFIER, '{', NULL);
3049                 }
3050
3051                 return NULL;
3052         }
3053
3054         if (compound == NULL) {
3055                 entity_kind_t  kind   = is_struct ? ENTITY_STRUCT : ENTITY_UNION;
3056                 entity_t      *entity = allocate_entity_zero(kind);
3057                 compound              = &entity->compound;
3058
3059                 compound->base.namespc =
3060                         (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
3061                 compound->base.source_position = token.source_position;
3062                 compound->base.symbol          = symbol;
3063                 compound->base.parent_scope    = current_scope;
3064                 if (symbol != NULL) {
3065                         environment_push(entity);
3066                 }
3067                 append_entity(current_scope, entity);
3068         }
3069
3070         if (token.type == '{') {
3071                 parse_compound_type_entries(compound);
3072                 modifiers |= parse_attributes(&attributes);
3073
3074                 if (symbol == NULL) {
3075                         assert(anonymous_entity == NULL);
3076                         anonymous_entity = (entity_t*)compound;
3077                 }
3078         }
3079
3080         compound->modifiers |= modifiers;
3081         return compound;
3082 }
3083
3084 static void parse_enum_entries(type_t *const enum_type)
3085 {
3086         eat('{');
3087
3088         if (token.type == '}') {
3089                 errorf(HERE, "empty enum not allowed");
3090                 next_token();
3091                 return;
3092         }
3093
3094         add_anchor_token('}');
3095         do {
3096                 if (token.type != T_IDENTIFIER) {
3097                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
3098                         eat_block();
3099                         rem_anchor_token('}');
3100                         return;
3101                 }
3102
3103                 entity_t *entity             = allocate_entity_zero(ENTITY_ENUM_VALUE);
3104                 entity->enum_value.enum_type = enum_type;
3105                 entity->base.symbol          = token.v.symbol;
3106                 entity->base.source_position = token.source_position;
3107                 next_token();
3108
3109                 if (token.type == '=') {
3110                         next_token();
3111                         expression_t *value = parse_constant_expression();
3112
3113                         value = create_implicit_cast(value, enum_type);
3114                         entity->enum_value.value = value;
3115
3116                         /* TODO semantic */
3117                 }
3118
3119                 record_entity(entity, false);
3120
3121                 if (token.type != ',')
3122                         break;
3123                 next_token();
3124         } while (token.type != '}');
3125         rem_anchor_token('}');
3126
3127         expect('}');
3128
3129 end_error:
3130         ;
3131 }
3132
3133 static type_t *parse_enum_specifier(void)
3134 {
3135         gnu_attribute_t *attributes = NULL;
3136         entity_t        *entity;
3137         symbol_t        *symbol;
3138
3139         eat(T_enum);
3140         if (token.type == T_IDENTIFIER) {
3141                 symbol = token.v.symbol;
3142                 next_token();
3143
3144                 entity = get_entity(symbol, NAMESPACE_ENUM);
3145                 assert(entity == NULL || entity->kind == ENTITY_ENUM);
3146         } else if (token.type != '{') {
3147                 parse_error_expected("while parsing enum type specifier",
3148                                      T_IDENTIFIER, '{', NULL);
3149                 return NULL;
3150         } else {
3151                 entity  = NULL;
3152                 symbol  = NULL;
3153         }
3154
3155         if (entity == NULL) {
3156                 entity                       = allocate_entity_zero(ENTITY_ENUM);
3157                 entity->base.namespc         = NAMESPACE_ENUM;
3158                 entity->base.source_position = token.source_position;
3159                 entity->base.symbol          = symbol;
3160                 entity->base.parent_scope    = current_scope;
3161         }
3162
3163         type_t *const type = allocate_type_zero(TYPE_ENUM);
3164         type->enumt.enume  = &entity->enume;
3165
3166         if (token.type == '{') {
3167                 if (entity->enume.complete) {
3168                         errorf(HERE, "multiple definitions of enum %Y (previous definition %P)",
3169                                symbol, &entity->base.source_position);
3170                 }
3171                 if (symbol != NULL) {
3172                         environment_push(entity);
3173                 }
3174                 append_entity(current_scope, entity);
3175                 entity->enume.complete = true;
3176
3177                 parse_enum_entries(type);
3178                 parse_attributes(&attributes);
3179
3180                 if (symbol == NULL) {
3181                         assert(anonymous_entity == NULL);
3182                         anonymous_entity = entity;
3183                 }
3184         } else if (!entity->enume.complete && !(c_mode & _GNUC)) {
3185                 errorf(HERE, "enum %Y used before definition (incomplete enumes are a GNU extension)",
3186                        symbol);
3187         }
3188
3189         return type;
3190 }
3191
3192 /**
3193  * if a symbol is a typedef to another type, return true
3194  */
3195 static bool is_typedef_symbol(symbol_t *symbol)
3196 {
3197         const entity_t *const entity = get_entity(symbol, NAMESPACE_NORMAL);
3198         return entity != NULL && entity->kind == ENTITY_TYPEDEF;
3199 }
3200
3201 static type_t *parse_typeof(void)
3202 {
3203         eat(T___typeof__);
3204
3205         type_t *type;
3206
3207         expect('(');
3208         add_anchor_token(')');
3209
3210         expression_t *expression  = NULL;
3211
3212         bool old_type_prop     = in_type_prop;
3213         bool old_gcc_extension = in_gcc_extension;
3214         in_type_prop           = true;
3215
3216         while (token.type == T___extension__) {
3217                 /* This can be a prefix to a typename or an expression. */
3218                 next_token();
3219                 in_gcc_extension = true;
3220         }
3221         switch (token.type) {
3222         case T_IDENTIFIER:
3223                 if (is_typedef_symbol(token.v.symbol)) {
3224                         type = parse_typename();
3225                 } else {
3226                         expression = parse_expression();
3227                         type       = expression->base.type;
3228                 }
3229                 break;
3230
3231         TYPENAME_START
3232                 type = parse_typename();
3233                 break;
3234
3235         default:
3236                 expression = parse_expression();
3237                 type       = expression->base.type;
3238                 break;
3239         }
3240         in_type_prop     = old_type_prop;
3241         in_gcc_extension = old_gcc_extension;
3242
3243         rem_anchor_token(')');
3244         expect(')');
3245
3246         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF);
3247         typeof_type->typeoft.expression  = expression;
3248         typeof_type->typeoft.typeof_type = type;
3249
3250         return typeof_type;
3251 end_error:
3252         return NULL;
3253 }
3254
3255 typedef enum specifiers_t {
3256         SPECIFIER_SIGNED    = 1 << 0,
3257         SPECIFIER_UNSIGNED  = 1 << 1,
3258         SPECIFIER_LONG      = 1 << 2,
3259         SPECIFIER_INT       = 1 << 3,
3260         SPECIFIER_DOUBLE    = 1 << 4,
3261         SPECIFIER_CHAR      = 1 << 5,
3262         SPECIFIER_SHORT     = 1 << 6,
3263         SPECIFIER_LONG_LONG = 1 << 7,
3264         SPECIFIER_FLOAT     = 1 << 8,
3265         SPECIFIER_BOOL      = 1 << 9,
3266         SPECIFIER_VOID      = 1 << 10,
3267         SPECIFIER_INT8      = 1 << 11,
3268         SPECIFIER_INT16     = 1 << 12,
3269         SPECIFIER_INT32     = 1 << 13,
3270         SPECIFIER_INT64     = 1 << 14,
3271         SPECIFIER_INT128    = 1 << 15,
3272         SPECIFIER_COMPLEX   = 1 << 16,
3273         SPECIFIER_IMAGINARY = 1 << 17,
3274 } specifiers_t;
3275
3276 static type_t *create_builtin_type(symbol_t *const symbol,
3277                                    type_t *const real_type)
3278 {
3279         type_t *type            = allocate_type_zero(TYPE_BUILTIN);
3280         type->builtin.symbol    = symbol;
3281         type->builtin.real_type = real_type;
3282
3283         type_t *result = typehash_insert(type);
3284         if (type != result) {
3285                 free_type(type);
3286         }
3287
3288         return result;
3289 }
3290
3291 static type_t *get_typedef_type(symbol_t *symbol)
3292 {
3293         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
3294         if (entity == NULL || entity->kind != ENTITY_TYPEDEF)
3295                 return NULL;
3296
3297         type_t *type            = allocate_type_zero(TYPE_TYPEDEF);
3298         type->typedeft.typedefe = &entity->typedefe;
3299
3300         return type;
3301 }
3302
3303 /**
3304  * check for the allowed MS alignment values.
3305  */
3306 static bool check_alignment_value(long long intvalue)
3307 {
3308         if (intvalue < 1 || intvalue > 8192) {
3309                 errorf(HERE, "illegal alignment value");
3310                 return false;
3311         }
3312         unsigned v = (unsigned)intvalue;
3313         for (unsigned i = 1; i <= 8192; i += i) {
3314                 if (i == v)
3315                         return true;
3316         }
3317         errorf(HERE, "alignment must be power of two");
3318         return false;
3319 }
3320
3321 #define DET_MOD(name, tag) do { \
3322         if (*modifiers & tag && warning.other) warningf(HERE, #name " used more than once"); \
3323         *modifiers |= tag; \
3324 } while (0)
3325
3326 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
3327 {
3328         decl_modifiers_t *modifiers = &specifiers->modifiers;
3329
3330         while (true) {
3331                 if (token.type == T_restrict) {
3332                         next_token();
3333                         DET_MOD(restrict, DM_RESTRICT);
3334                         goto end_loop;
3335                 } else if (token.type != T_IDENTIFIER)
3336                         break;
3337                 symbol_t *symbol = token.v.symbol;
3338                 if (symbol == sym_align) {
3339                         next_token();
3340                         expect('(');
3341                         if (token.type != T_INTEGER)
3342                                 goto end_error;
3343                         if (check_alignment_value(token.v.intvalue)) {
3344                                 if (specifiers->alignment != 0 && warning.other)
3345                                         warningf(HERE, "align used more than once");
3346                                 specifiers->alignment = (unsigned char)token.v.intvalue;
3347                         }
3348                         next_token();
3349                         expect(')');
3350                 } else if (symbol == sym_allocate) {
3351                         next_token();
3352                         expect('(');
3353                         if (token.type != T_IDENTIFIER)
3354                                 goto end_error;
3355                         (void)token.v.symbol;
3356                         expect(')');
3357                 } else if (symbol == sym_dllimport) {
3358                         next_token();
3359                         DET_MOD(dllimport, DM_DLLIMPORT);
3360                 } else if (symbol == sym_dllexport) {
3361                         next_token();
3362                         DET_MOD(dllexport, DM_DLLEXPORT);
3363                 } else if (symbol == sym_thread) {
3364                         next_token();
3365                         DET_MOD(thread, DM_THREAD);
3366                 } else if (symbol == sym_naked) {
3367                         next_token();
3368                         DET_MOD(naked, DM_NAKED);
3369                 } else if (symbol == sym_noinline) {
3370                         next_token();
3371                         DET_MOD(noinline, DM_NOINLINE);
3372                 } else if (symbol == sym_noreturn) {
3373                         next_token();
3374                         DET_MOD(noreturn, DM_NORETURN);
3375                 } else if (symbol == sym_nothrow) {
3376                         next_token();
3377                         DET_MOD(nothrow, DM_NOTHROW);
3378                 } else if (symbol == sym_novtable) {
3379                         next_token();
3380                         DET_MOD(novtable, DM_NOVTABLE);
3381                 } else if (symbol == sym_property) {
3382                         next_token();
3383                         expect('(');
3384                         for (;;) {
3385                                 bool is_get = false;
3386                                 if (token.type != T_IDENTIFIER)
3387                                         goto end_error;
3388                                 if (token.v.symbol == sym_get) {
3389                                         is_get = true;
3390                                 } else if (token.v.symbol == sym_put) {
3391                                 } else {
3392                                         errorf(HERE, "Bad property name '%Y'", token.v.symbol);
3393                                         goto end_error;
3394                                 }
3395                                 next_token();
3396                                 expect('=');
3397                                 if (token.type != T_IDENTIFIER)
3398                                         goto end_error;
3399                                 if (is_get) {
3400                                         if (specifiers->get_property_sym != NULL) {
3401                                                 errorf(HERE, "get property name already specified");
3402                                         } else {
3403                                                 specifiers->get_property_sym = token.v.symbol;
3404                                         }
3405                                 } else {
3406                                         if (specifiers->put_property_sym != NULL) {
3407                                                 errorf(HERE, "put property name already specified");
3408                                         } else {
3409                                                 specifiers->put_property_sym = token.v.symbol;
3410                                         }
3411                                 }
3412                                 next_token();
3413                                 if (token.type == ',') {
3414                                         next_token();
3415                                         continue;
3416                                 }
3417                                 break;
3418                         }
3419                         expect(')');
3420                 } else if (symbol == sym_selectany) {
3421                         next_token();
3422                         DET_MOD(selectany, DM_SELECTANY);
3423                 } else if (symbol == sym_uuid) {
3424                         next_token();
3425                         expect('(');
3426                         if (token.type != T_STRING_LITERAL)
3427                                 goto end_error;
3428                         next_token();
3429                         expect(')');
3430                 } else if (symbol == sym_deprecated) {
3431                         next_token();
3432                         if (specifiers->deprecated != 0 && warning.other)
3433                                 warningf(HERE, "deprecated used more than once");
3434                         specifiers->deprecated = true;
3435                         if (token.type == '(') {
3436                                 next_token();
3437                                 if (token.type == T_STRING_LITERAL) {
3438                                         specifiers->deprecated_string = token.v.string.begin;
3439                                         next_token();
3440                                 } else {
3441                                         errorf(HERE, "string literal expected");
3442                                 }
3443                                 expect(')');
3444                         }
3445                 } else if (symbol == sym_noalias) {
3446                         next_token();
3447                         DET_MOD(noalias, DM_NOALIAS);
3448                 } else {
3449                         if (warning.other)
3450                                 warningf(HERE, "Unknown modifier %Y ignored", token.v.symbol);
3451                         next_token();
3452                         if (token.type == '(')
3453                                 skip_until(')');
3454                 }
3455 end_loop:
3456                 if (token.type == ',')
3457                         next_token();
3458         }
3459 end_error:
3460         return;
3461 }
3462
3463 static entity_t *create_error_entity(symbol_t *symbol, entity_kind_tag_t kind)
3464 {
3465         entity_t *entity             = allocate_entity_zero(kind);
3466         entity->base.source_position = *HERE;
3467         entity->base.symbol          = symbol;
3468         if (is_declaration(entity)) {
3469                 entity->declaration.type     = type_error_type;
3470                 entity->declaration.implicit = true;
3471         } else if (kind == ENTITY_TYPEDEF) {
3472                 entity->typedefe.type = type_error_type;
3473         }
3474         record_entity(entity, false);
3475         return entity;
3476 }
3477
3478 static void parse_microsoft_based(based_spec_t *based_spec)
3479 {
3480         if (token.type != T_IDENTIFIER) {
3481                 parse_error_expected("while parsing __based", T_IDENTIFIER, NULL);
3482                 return;
3483         }
3484         symbol_t *symbol = token.v.symbol;
3485         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
3486
3487         if (entity == NULL || entity->base.kind != ENTITY_VARIABLE) {
3488                 errorf(HERE, "'%Y' is not a variable name.", symbol);
3489                 entity = create_error_entity(symbol, ENTITY_VARIABLE);
3490         } else {
3491                 variable_t *variable = &entity->variable;
3492
3493                 if (based_spec->base_variable != NULL) {
3494                         errorf(HERE, "__based type qualifier specified more than once");
3495                 }
3496                 based_spec->source_position = token.source_position;
3497                 based_spec->base_variable   = variable;
3498
3499                 type_t *const type = variable->base.type;
3500
3501                 if (is_type_valid(type)) {
3502                         if (! is_type_pointer(skip_typeref(type))) {
3503                                 errorf(HERE, "variable in __based modifier must have pointer type instead of '%T'", type);
3504                         }
3505                         if (variable->base.base.parent_scope != file_scope) {
3506                                 errorf(HERE, "a nonstatic local variable may not be used in a __based specification");
3507                         }
3508                 }
3509         }
3510         next_token();
3511 }
3512
3513 /**
3514  * Finish the construction of a struct type by calculating
3515  * its size, offsets, alignment.
3516  */
3517 static void finish_struct_type(compound_type_t *type)
3518 {
3519         assert(type->compound != NULL);
3520
3521         compound_t *compound = type->compound;
3522         if (!compound->complete)
3523                 return;
3524
3525         il_size_t      size           = 0;
3526         il_size_t      offset;
3527         il_alignment_t alignment      = 1;
3528         bool           need_pad       = false;
3529
3530         entity_t *entry = compound->members.entities;
3531         for (; entry != NULL; entry = entry->base.next) {
3532                 if (entry->kind != ENTITY_COMPOUND_MEMBER)
3533                         continue;
3534
3535                 type_t *m_type = skip_typeref(entry->declaration.type);
3536                 if (! is_type_valid(m_type)) {
3537                         /* simply ignore errors here */
3538                         continue;
3539                 }
3540                 il_alignment_t m_alignment = m_type->base.alignment;
3541                 if (m_alignment > alignment)
3542                         alignment = m_alignment;
3543
3544                 offset = (size + m_alignment - 1) & -m_alignment;
3545
3546                 if (offset > size)
3547                         need_pad = true;
3548                 entry->compound_member.offset = offset;
3549                 size = offset + m_type->base.size;
3550         }
3551         if (type->base.alignment != 0) {
3552                 alignment = type->base.alignment;
3553         }
3554
3555         offset = (size + alignment - 1) & -alignment;
3556         if (offset > size)
3557                 need_pad = true;
3558
3559         if (warning.padded && need_pad) {
3560                 warningf(&compound->base.source_position,
3561                         "'%#T' needs padding", type, compound->base.symbol);
3562         }
3563         if (warning.packed && !need_pad) {
3564                 warningf(&compound->base.source_position,
3565                         "superfluous packed attribute on '%#T'",
3566                         type, compound->base.symbol);
3567         }
3568
3569         type->base.size      = offset;
3570         type->base.alignment = alignment;
3571 }
3572
3573 /**
3574  * Finish the construction of an union type by calculating
3575  * its size and alignment.
3576  */
3577 static void finish_union_type(compound_type_t *type)
3578 {
3579         assert(type->compound != NULL);
3580
3581         compound_t *compound = type->compound;
3582         if (! compound->complete)
3583                 return;
3584
3585         il_size_t      size      = 0;
3586         il_alignment_t alignment = 1;
3587
3588         entity_t *entry = compound->members.entities;
3589         for (; entry != NULL; entry = entry->base.next) {
3590                 if (entry->kind != ENTITY_COMPOUND_MEMBER)
3591                         continue;
3592
3593                 type_t *m_type = skip_typeref(entry->declaration.type);
3594                 if (! is_type_valid(m_type))
3595                         continue;
3596
3597                 entry->compound_member.offset = 0;
3598                 if (m_type->base.size > size)
3599                         size = m_type->base.size;
3600                 if (m_type->base.alignment > alignment)
3601                         alignment = m_type->base.alignment;
3602         }
3603         if (type->base.alignment != 0) {
3604                 alignment = type->base.alignment;
3605         }
3606         size = (size + alignment - 1) & -alignment;
3607         type->base.size      = size;
3608         type->base.alignment = alignment;
3609 }
3610
3611 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
3612 {
3613         type_t            *type              = NULL;
3614         type_qualifiers_t  qualifiers        = TYPE_QUALIFIER_NONE;
3615         type_modifiers_t   modifiers         = TYPE_MODIFIER_NONE;
3616         unsigned           type_specifiers   = 0;
3617         bool               newtype           = false;
3618         bool               saw_error         = false;
3619         bool               old_gcc_extension = in_gcc_extension;
3620
3621         specifiers->source_position = token.source_position;
3622
3623         while (true) {
3624                 specifiers->modifiers
3625                         |= parse_attributes(&specifiers->gnu_attributes);
3626                 if (specifiers->modifiers & DM_TRANSPARENT_UNION)
3627                         modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3628
3629                 switch (token.type) {
3630                 /* storage class */
3631 #define MATCH_STORAGE_CLASS(token, class)                                  \
3632                 case token:                                                        \
3633                         if (specifiers->storage_class != STORAGE_CLASS_NONE) {         \
3634                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3635                         }                                                              \
3636                         specifiers->storage_class = class;                             \
3637                         if (specifiers->thread_local)                                  \
3638                                 goto check_thread_storage_class;                           \
3639                         next_token();                                                  \
3640                         break;
3641
3642                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3643                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3644                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3645                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3646                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3647
3648                 case T__declspec:
3649                         next_token();
3650                         expect('(');
3651                         add_anchor_token(')');
3652                         parse_microsoft_extended_decl_modifier(specifiers);
3653                         rem_anchor_token(')');
3654                         expect(')');
3655                         break;
3656
3657                 case T___thread:
3658                         if (specifiers->thread_local) {
3659                                 errorf(HERE, "duplicate '__thread'");
3660                         } else {
3661                                 specifiers->thread_local = true;
3662 check_thread_storage_class:
3663                                 switch (specifiers->storage_class) {
3664                                         case STORAGE_CLASS_EXTERN:
3665                                         case STORAGE_CLASS_NONE:
3666                                         case STORAGE_CLASS_STATIC:
3667                                                 break;
3668
3669                                                 char const* wrong;
3670                                         case STORAGE_CLASS_AUTO:     wrong = "auto";     goto wrong_thread_stoarge_class;
3671                                         case STORAGE_CLASS_REGISTER: wrong = "register"; goto wrong_thread_stoarge_class;
3672                                         case STORAGE_CLASS_TYPEDEF:  wrong = "typedef";  goto wrong_thread_stoarge_class;
3673 wrong_thread_stoarge_class:
3674                                                 errorf(HERE, "'__thread' used with '%s'", wrong);
3675                                                 break;
3676                                 }
3677                         }
3678                         next_token();
3679                         break;
3680
3681                 /* type qualifiers */
3682 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3683                 case token:                                                     \
3684                         qualifiers |= qualifier;                                    \
3685                         next_token();                                               \
3686                         break
3687
3688                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3689                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3690                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3691                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3692                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3693                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3694                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3695                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3696
3697                 case T___extension__:
3698                         next_token();
3699                         in_gcc_extension = true;
3700                         break;
3701
3702                 /* type specifiers */
3703 #define MATCH_SPECIFIER(token, specifier, name)                         \
3704                 case token:                                                     \
3705                         if (type_specifiers & specifier) {                           \
3706                                 errorf(HERE, "multiple " name " type specifiers given"); \
3707                         } else {                                                    \
3708                                 type_specifiers |= specifier;                           \
3709                         }                                                           \
3710                         next_token();                                               \
3711                         break
3712
3713                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3714                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3715                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3716                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3717                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3718                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3719                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3720                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3721                 MATCH_SPECIFIER(T_bool,       SPECIFIER_BOOL,      "bool");
3722                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3723                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3724                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3725                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3726                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3727                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3728                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3729                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3730
3731                 case T__forceinline:
3732                         /* only in microsoft mode */
3733                         specifiers->modifiers |= DM_FORCEINLINE;
3734                         /* FALLTHROUGH */
3735
3736                 case T_inline:
3737                         next_token();
3738                         specifiers->is_inline = true;
3739                         break;
3740
3741                 case T_long:
3742                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3743                                 errorf(HERE, "multiple type specifiers given");
3744                         } else if (type_specifiers & SPECIFIER_LONG) {
3745                                 type_specifiers |= SPECIFIER_LONG_LONG;
3746                         } else {
3747                                 type_specifiers |= SPECIFIER_LONG;
3748                         }
3749                         next_token();
3750                         break;
3751
3752                 case T_struct: {
3753                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT);
3754
3755                         type->compound.compound = parse_compound_type_specifier(true);
3756                         finish_struct_type(&type->compound);
3757                         break;
3758                 }
3759                 case T_union: {
3760                         type = allocate_type_zero(TYPE_COMPOUND_UNION);
3761                         type->compound.compound = parse_compound_type_specifier(false);
3762                         if (type->compound.compound->modifiers & DM_TRANSPARENT_UNION)
3763                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3764                         finish_union_type(&type->compound);
3765                         break;
3766                 }
3767                 case T_enum:
3768                         type = parse_enum_specifier();
3769                         break;
3770                 case T___typeof__:
3771                         type = parse_typeof();
3772                         break;
3773                 case T___builtin_va_list:
3774                         type = duplicate_type(type_valist);
3775                         next_token();
3776                         break;
3777
3778                 case T_IDENTIFIER: {
3779                         /* only parse identifier if we haven't found a type yet */
3780                         if (type != NULL || type_specifiers != 0) {
3781                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
3782                                  * declaration, so it doesn't generate errors about expecting '(' or
3783                                  * '{' later on. */
3784                                 switch (look_ahead(1)->type) {
3785                                         STORAGE_CLASSES
3786                                         TYPE_SPECIFIERS
3787                                         case T_const:
3788                                         case T_restrict:
3789                                         case T_volatile:
3790                                         case T_inline:
3791                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
3792                                         case T_IDENTIFIER:
3793                                         case '&':
3794                                         case '*':
3795                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
3796                                                 next_token();
3797                                                 continue;
3798
3799                                         default:
3800                                                 goto finish_specifiers;
3801                                 }
3802                         }
3803
3804                         type_t *const typedef_type = get_typedef_type(token.v.symbol);
3805                         if (typedef_type == NULL) {
3806                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3807                                  * declaration, so it doesn't generate 'implicit int' followed by more
3808                                  * errors later on. */
3809                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3810                                 switch (la1_type) {
3811                                         DECLARATION_START
3812                                         case T_IDENTIFIER:
3813                                         case '&':
3814                                         case '*': {
3815                                                 errorf(HERE, "%K does not name a type", &token);
3816
3817                                                 entity_t *entity =
3818                                                         create_error_entity(token.v.symbol, ENTITY_TYPEDEF);
3819
3820                                                 type = allocate_type_zero(TYPE_TYPEDEF);
3821                                                 type->typedeft.typedefe = &entity->typedefe;
3822
3823                                                 next_token();
3824                                                 saw_error = true;
3825                                                 if (la1_type == '&' || la1_type == '*')
3826                                                         goto finish_specifiers;
3827                                                 continue;
3828                                         }
3829
3830                                         default:
3831                                                 goto finish_specifiers;
3832                                 }
3833                         }
3834
3835                         next_token();
3836                         type = typedef_type;
3837                         break;
3838                 }
3839
3840                 /* function specifier */
3841                 default:
3842                         goto finish_specifiers;
3843                 }
3844         }
3845
3846 finish_specifiers:
3847         in_gcc_extension = old_gcc_extension;
3848
3849         if (type == NULL || (saw_error && type_specifiers != 0)) {
3850                 atomic_type_kind_t atomic_type;
3851
3852                 /* match valid basic types */
3853                 switch (type_specifiers) {
3854                 case SPECIFIER_VOID:
3855                         atomic_type = ATOMIC_TYPE_VOID;
3856                         break;
3857                 case SPECIFIER_CHAR:
3858                         atomic_type = ATOMIC_TYPE_CHAR;
3859                         break;
3860                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3861                         atomic_type = ATOMIC_TYPE_SCHAR;
3862                         break;
3863                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3864                         atomic_type = ATOMIC_TYPE_UCHAR;
3865                         break;
3866                 case SPECIFIER_SHORT:
3867                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3868                 case SPECIFIER_SHORT | SPECIFIER_INT:
3869                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3870                         atomic_type = ATOMIC_TYPE_SHORT;
3871                         break;
3872                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3873                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3874                         atomic_type = ATOMIC_TYPE_USHORT;
3875                         break;
3876                 case SPECIFIER_INT:
3877                 case SPECIFIER_SIGNED:
3878                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3879                         atomic_type = ATOMIC_TYPE_INT;
3880                         break;
3881                 case SPECIFIER_UNSIGNED:
3882                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3883                         atomic_type = ATOMIC_TYPE_UINT;
3884                         break;
3885                 case SPECIFIER_LONG:
3886                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3887                 case SPECIFIER_LONG | SPECIFIER_INT:
3888                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3889                         atomic_type = ATOMIC_TYPE_LONG;
3890                         break;
3891                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3892                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3893                         atomic_type = ATOMIC_TYPE_ULONG;
3894                         break;
3895
3896                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3897                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3898                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3899                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3900                         | SPECIFIER_INT:
3901                         atomic_type = ATOMIC_TYPE_LONGLONG;
3902                         goto warn_about_long_long;
3903
3904                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3905                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3906                         | SPECIFIER_INT:
3907                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3908 warn_about_long_long:
3909                         if (warning.long_long) {
3910                                 warningf(&specifiers->source_position,
3911                                          "ISO C90 does not support 'long long'");
3912                         }
3913                         break;
3914
3915                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3916                         atomic_type = unsigned_int8_type_kind;
3917                         break;
3918
3919                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3920                         atomic_type = unsigned_int16_type_kind;
3921                         break;
3922
3923                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3924                         atomic_type = unsigned_int32_type_kind;
3925                         break;
3926
3927                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3928                         atomic_type = unsigned_int64_type_kind;
3929                         break;
3930
3931                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3932                         atomic_type = unsigned_int128_type_kind;
3933                         break;
3934
3935                 case SPECIFIER_INT8:
3936                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3937                         atomic_type = int8_type_kind;
3938                         break;
3939
3940                 case SPECIFIER_INT16:
3941                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3942                         atomic_type = int16_type_kind;
3943                         break;
3944
3945                 case SPECIFIER_INT32:
3946                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3947                         atomic_type = int32_type_kind;
3948                         break;
3949
3950                 case SPECIFIER_INT64:
3951                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3952                         atomic_type = int64_type_kind;
3953                         break;
3954
3955                 case SPECIFIER_INT128:
3956                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3957                         atomic_type = int128_type_kind;
3958                         break;
3959
3960                 case SPECIFIER_FLOAT:
3961                         atomic_type = ATOMIC_TYPE_FLOAT;
3962                         break;
3963                 case SPECIFIER_DOUBLE:
3964                         atomic_type = ATOMIC_TYPE_DOUBLE;
3965                         break;
3966                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3967                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3968                         break;
3969                 case SPECIFIER_BOOL:
3970                         atomic_type = ATOMIC_TYPE_BOOL;
3971                         break;
3972                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3973                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3974                         atomic_type = ATOMIC_TYPE_FLOAT;
3975                         break;
3976                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3977                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3978                         atomic_type = ATOMIC_TYPE_DOUBLE;
3979                         break;
3980                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3981                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3982                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3983                         break;
3984                 default:
3985                         /* invalid specifier combination, give an error message */
3986                         if (type_specifiers == 0) {
3987                                 if (saw_error)
3988                                         goto end_error;
3989
3990                                 /* ISO/IEC 14882:1998(E) §C.1.5:4 */
3991                                 if (!(c_mode & _CXX) && !strict_mode) {
3992                                         if (warning.implicit_int) {
3993                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
3994                                         }
3995                                         atomic_type = ATOMIC_TYPE_INT;
3996                                         break;
3997                                 } else {
3998                                         errorf(HERE, "no type specifiers given in declaration");
3999                                 }
4000                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
4001                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
4002                                 errorf(HERE, "signed and unsigned specifiers given");
4003                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
4004                                 errorf(HERE, "only integer types can be signed or unsigned");
4005                         } else {
4006                                 errorf(HERE, "multiple datatypes in declaration");
4007                         }
4008                         goto end_error;
4009                 }
4010
4011                 if (type_specifiers & SPECIFIER_COMPLEX) {
4012                         type                = allocate_type_zero(TYPE_COMPLEX);
4013                         type->complex.akind = atomic_type;
4014                 } else if (type_specifiers & SPECIFIER_IMAGINARY) {
4015                         type                  = allocate_type_zero(TYPE_IMAGINARY);
4016                         type->imaginary.akind = atomic_type;
4017                 } else {
4018                         type               = allocate_type_zero(TYPE_ATOMIC);
4019                         type->atomic.akind = atomic_type;
4020                 }
4021                 newtype = true;
4022         } else if (type_specifiers != 0) {
4023                 errorf(HERE, "multiple datatypes in declaration");
4024         }
4025
4026         /* FIXME: check type qualifiers here */
4027
4028         type->base.qualifiers = qualifiers;
4029         type->base.modifiers  = modifiers;
4030
4031         type_t *result = typehash_insert(type);
4032         if (newtype && result != type) {
4033                 free_type(type);
4034         }
4035
4036         specifiers->type = result;
4037         return;
4038
4039 end_error:
4040         specifiers->type = type_error_type;
4041         return;
4042 }
4043
4044 static type_qualifiers_t parse_type_qualifiers(void)
4045 {
4046         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
4047
4048         while (true) {
4049                 switch (token.type) {
4050                 /* type qualifiers */
4051                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
4052                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
4053                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
4054                 /* microsoft extended type modifiers */
4055                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
4056                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
4057                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
4058                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
4059                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
4060
4061                 default:
4062                         return qualifiers;
4063                 }
4064         }
4065 }
4066
4067 /**
4068  * Parses an K&R identifier list
4069  */
4070 static void parse_identifier_list(scope_t *scope)
4071 {
4072         do {
4073                 entity_t *entity = allocate_entity_zero(ENTITY_PARAMETER);
4074                 entity->base.source_position = token.source_position;
4075                 entity->base.namespc         = NAMESPACE_NORMAL;
4076                 entity->base.symbol          = token.v.symbol;
4077                 /* a K&R parameter has no type, yet */
4078                 next_token();
4079
4080                 append_entity(scope, entity);
4081
4082                 if (token.type != ',') {
4083                         break;
4084                 }
4085                 next_token();
4086         } while (token.type == T_IDENTIFIER);
4087 }
4088
4089 static entity_t *parse_parameter(void)
4090 {
4091         declaration_specifiers_t specifiers;
4092         memset(&specifiers, 0, sizeof(specifiers));
4093
4094         parse_declaration_specifiers(&specifiers);
4095
4096         entity_t *entity = parse_declarator(&specifiers,
4097                         DECL_MAY_BE_ABSTRACT | DECL_IS_PARAMETER);
4098         anonymous_entity = NULL;
4099         return entity;
4100 }
4101
4102 static void semantic_parameter_incomplete(const entity_t *entity)
4103 {
4104         assert(entity->kind == ENTITY_PARAMETER);
4105
4106         /* §6.7.5.3:4  After adjustment, the parameters in a parameter type
4107          *             list in a function declarator that is part of a
4108          *             definition of that function shall not have
4109          *             incomplete type. */
4110         type_t *type = skip_typeref(entity->declaration.type);
4111         if (is_type_incomplete(type)) {
4112                 errorf(&entity->base.source_position,
4113                        "parameter '%Y' has incomplete type %T", entity->base.symbol,
4114                        entity->declaration.type);
4115         }
4116 }
4117
4118 /**
4119  * Parses function type parameters (and optionally creates variable_t entities
4120  * for them in a scope)
4121  */
4122 static void parse_parameters(function_type_t *type, scope_t *scope)
4123 {
4124         eat('(');
4125         add_anchor_token(')');
4126         int saved_comma_state = save_and_reset_anchor_state(',');
4127
4128         if (token.type == T_IDENTIFIER &&
4129             !is_typedef_symbol(token.v.symbol)) {
4130                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
4131                 if (la1_type == ',' || la1_type == ')') {
4132                         type->kr_style_parameters = true;
4133                         parse_identifier_list(scope);
4134                         goto parameters_finished;
4135                 }
4136         }
4137
4138         if (token.type == ')') {
4139                 /* ISO/IEC 14882:1998(E) §C.1.6:1 */
4140                 if (!(c_mode & _CXX))
4141                         type->unspecified_parameters = true;
4142                 goto parameters_finished;
4143         }
4144
4145         function_parameter_t *parameter;
4146         function_parameter_t *last_parameter = NULL;
4147
4148         while (true) {
4149                 switch (token.type) {
4150                 case T_DOTDOTDOT:
4151                         next_token();
4152                         type->variadic = true;
4153                         goto parameters_finished;
4154
4155                 case T_IDENTIFIER:
4156                 case T___extension__:
4157                 DECLARATION_START
4158                 {
4159                         entity_t *entity = parse_parameter();
4160                         if (entity->kind == ENTITY_TYPEDEF) {
4161                                 errorf(&entity->base.source_position,
4162                                        "typedef not allowed as function parameter");
4163                                 break;
4164                         }
4165                         assert(is_declaration(entity));
4166
4167                         /* func(void) is not a parameter */
4168                         if (last_parameter == NULL
4169                                         && token.type == ')'
4170                                         && entity->base.symbol == NULL
4171                                         && skip_typeref(entity->declaration.type) == type_void) {
4172                                 goto parameters_finished;
4173                         }
4174                         semantic_parameter_incomplete(entity);
4175
4176                         parameter = obstack_alloc(type_obst, sizeof(parameter[0]));
4177                         memset(parameter, 0, sizeof(parameter[0]));
4178                         parameter->type = entity->declaration.type;
4179
4180                         if (scope != NULL) {
4181                                 append_entity(scope, entity);
4182                         }
4183
4184                         if (last_parameter != NULL) {
4185                                 last_parameter->next = parameter;
4186                         } else {
4187                                 type->parameters = parameter;
4188                         }
4189                         last_parameter   = parameter;
4190                         break;
4191                 }
4192
4193                 default:
4194                         goto parameters_finished;
4195                 }
4196                 if (token.type != ',') {
4197                         goto parameters_finished;
4198                 }
4199                 next_token();
4200         }
4201
4202
4203 parameters_finished:
4204         rem_anchor_token(')');
4205         expect(')');
4206
4207 end_error:
4208         restore_anchor_state(',', saved_comma_state);
4209 }
4210
4211 typedef enum construct_type_kind_t {
4212         CONSTRUCT_INVALID,
4213         CONSTRUCT_POINTER,
4214         CONSTRUCT_REFERENCE,
4215         CONSTRUCT_FUNCTION,
4216         CONSTRUCT_ARRAY
4217 } construct_type_kind_t;
4218
4219 typedef struct construct_type_t construct_type_t;
4220 struct construct_type_t {
4221         construct_type_kind_t  kind;
4222         construct_type_t      *next;
4223 };
4224
4225 typedef struct parsed_pointer_t parsed_pointer_t;
4226 struct parsed_pointer_t {
4227         construct_type_t  construct_type;
4228         type_qualifiers_t type_qualifiers;
4229         variable_t        *base_variable;  /**< MS __based extension. */
4230 };
4231
4232 typedef struct parsed_reference_t parsed_reference_t;
4233 struct parsed_reference_t {
4234         construct_type_t construct_type;
4235 };
4236
4237 typedef struct construct_function_type_t construct_function_type_t;
4238 struct construct_function_type_t {
4239         construct_type_t  construct_type;
4240         type_t           *function_type;
4241 };
4242
4243 typedef struct parsed_array_t parsed_array_t;
4244 struct parsed_array_t {
4245         construct_type_t  construct_type;
4246         type_qualifiers_t type_qualifiers;
4247         bool              is_static;
4248         bool              is_variable;
4249         expression_t     *size;
4250 };
4251
4252 typedef struct construct_base_type_t construct_base_type_t;
4253 struct construct_base_type_t {
4254         construct_type_t  construct_type;
4255         type_t           *type;
4256 };
4257
4258 static construct_type_t *parse_pointer_declarator(variable_t *base_variable)
4259 {
4260         eat('*');
4261
4262         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
4263         memset(pointer, 0, sizeof(pointer[0]));
4264         pointer->construct_type.kind = CONSTRUCT_POINTER;
4265         pointer->type_qualifiers     = parse_type_qualifiers();
4266         pointer->base_variable       = base_variable;
4267
4268         return &pointer->construct_type;
4269 }
4270
4271 static construct_type_t *parse_reference_declarator(void)
4272 {
4273         eat('&');
4274
4275         parsed_reference_t *reference = obstack_alloc(&temp_obst, sizeof(reference[0]));
4276         memset(reference, 0, sizeof(reference[0]));
4277         reference->construct_type.kind = CONSTRUCT_REFERENCE;
4278
4279         return (construct_type_t*)reference;
4280 }
4281
4282 static construct_type_t *parse_array_declarator(void)
4283 {
4284         eat('[');
4285         add_anchor_token(']');
4286
4287         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
4288         memset(array, 0, sizeof(array[0]));
4289         array->construct_type.kind = CONSTRUCT_ARRAY;
4290
4291         if (token.type == T_static) {
4292                 array->is_static = true;
4293                 next_token();
4294         }
4295
4296         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
4297         if (type_qualifiers != 0) {
4298                 if (token.type == T_static) {
4299                         array->is_static = true;
4300                         next_token();
4301                 }
4302         }
4303         array->type_qualifiers = type_qualifiers;
4304
4305         if (token.type == '*' && look_ahead(1)->type == ']') {
4306                 array->is_variable = true;
4307                 next_token();
4308         } else if (token.type != ']') {
4309                 array->size = parse_assignment_expression();
4310         }
4311
4312         rem_anchor_token(']');
4313         expect(']');
4314
4315 end_error:
4316         return &array->construct_type;
4317 }
4318
4319 static construct_type_t *parse_function_declarator(scope_t *scope,
4320                                                    decl_modifiers_t modifiers)
4321 {
4322         type_t          *type  = allocate_type_zero(TYPE_FUNCTION);
4323         function_type_t *ftype = &type->function;
4324
4325         ftype->linkage = current_linkage;
4326
4327         switch (modifiers & (DM_CDECL | DM_STDCALL | DM_FASTCALL | DM_THISCALL)) {
4328                 case DM_NONE:     break;
4329                 case DM_CDECL:    ftype->calling_convention = CC_CDECL;    break;
4330                 case DM_STDCALL:  ftype->calling_convention = CC_STDCALL;  break;
4331                 case DM_FASTCALL: ftype->calling_convention = CC_FASTCALL; break;
4332                 case DM_THISCALL: ftype->calling_convention = CC_THISCALL; break;
4333
4334                 default:
4335                         errorf(HERE, "multiple calling conventions in declaration");
4336                         break;
4337         }
4338
4339         parse_parameters(ftype, scope);
4340
4341         construct_function_type_t *construct_function_type =
4342                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
4343         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
4344         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
4345         construct_function_type->function_type       = type;
4346
4347         return &construct_function_type->construct_type;
4348 }
4349
4350 typedef struct parse_declarator_env_t {
4351         decl_modifiers_t   modifiers;
4352         symbol_t          *symbol;
4353         source_position_t  source_position;
4354         scope_t            parameters;
4355 } parse_declarator_env_t;
4356
4357 static construct_type_t *parse_inner_declarator(parse_declarator_env_t *env,
4358                 bool may_be_abstract)
4359 {
4360         /* construct a single linked list of construct_type_t's which describe
4361          * how to construct the final declarator type */
4362         construct_type_t *first      = NULL;
4363         construct_type_t *last       = NULL;
4364         gnu_attribute_t  *attributes = NULL;
4365
4366         decl_modifiers_t modifiers = parse_attributes(&attributes);
4367
4368         /* MS __based extension */
4369         based_spec_t base_spec;
4370         base_spec.base_variable = NULL;
4371
4372         for (;;) {
4373                 construct_type_t *type;
4374                 switch (token.type) {
4375                         case '&':
4376                                 if (!(c_mode & _CXX))
4377                                         errorf(HERE, "references are only available for C++");
4378                                 if (base_spec.base_variable != NULL && warning.other) {
4379                                         warningf(&base_spec.source_position,
4380                                                  "__based does not precede a pointer operator, ignored");
4381                                 }
4382                                 type = parse_reference_declarator();
4383                                 /* consumed */
4384                                 base_spec.base_variable = NULL;
4385                                 break;
4386
4387                         case '*':
4388                                 type = parse_pointer_declarator(base_spec.base_variable);
4389                                 /* consumed */
4390                                 base_spec.base_variable = NULL;
4391                                 break;
4392
4393                         case T__based:
4394                                 next_token();
4395                                 expect('(');
4396                                 add_anchor_token(')');
4397                                 parse_microsoft_based(&base_spec);
4398                                 rem_anchor_token(')');
4399                                 expect(')');
4400                                 continue;
4401
4402                         default:
4403                                 goto ptr_operator_end;
4404                 }
4405
4406                 if (last == NULL) {
4407                         first = type;
4408                         last  = type;
4409                 } else {
4410                         last->next = type;
4411                         last       = type;
4412                 }
4413
4414                 /* TODO: find out if this is correct */
4415                 modifiers |= parse_attributes(&attributes);
4416         }
4417 ptr_operator_end:
4418         if (base_spec.base_variable != NULL && warning.other) {
4419                 warningf(&base_spec.source_position,
4420                          "__based does not precede a pointer operator, ignored");
4421         }
4422
4423         if (env != NULL) {
4424                 modifiers      |= env->modifiers;
4425                 env->modifiers  = modifiers;
4426         }
4427
4428         construct_type_t *inner_types = NULL;
4429
4430         switch (token.type) {
4431         case T_IDENTIFIER:
4432                 if (env == NULL) {
4433                         errorf(HERE, "no identifier expected in typename");
4434                 } else {
4435                         env->symbol          = token.v.symbol;
4436                         env->source_position = token.source_position;
4437                 }
4438                 next_token();
4439                 break;
4440         case '(':
4441                 next_token();
4442                 add_anchor_token(')');
4443                 inner_types = parse_inner_declarator(env, may_be_abstract);
4444                 if (inner_types != NULL) {
4445                         /* All later declarators only modify the return type */
4446                         env = NULL;
4447                 }
4448                 rem_anchor_token(')');
4449                 expect(')');
4450                 break;
4451         default:
4452                 if (may_be_abstract)
4453                         break;
4454                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
4455                 eat_until_anchor();
4456                 return NULL;
4457         }
4458
4459         construct_type_t *p = last;
4460
4461         while (true) {
4462                 construct_type_t *type;
4463                 switch (token.type) {
4464                 case '(': {
4465                         scope_t *scope = NULL;
4466                         if (env != NULL)
4467                                 scope = &env->parameters;
4468
4469                         type = parse_function_declarator(scope, modifiers);
4470                         break;
4471                 }
4472                 case '[':
4473                         type = parse_array_declarator();
4474                         break;
4475                 default:
4476                         goto declarator_finished;
4477                 }
4478
4479                 /* insert in the middle of the list (behind p) */
4480                 if (p != NULL) {
4481                         type->next = p->next;
4482                         p->next    = type;
4483                 } else {
4484                         type->next = first;
4485                         first      = type;
4486                 }
4487                 if (last == p) {
4488                         last = type;
4489                 }
4490         }
4491
4492 declarator_finished:
4493         /* append inner_types at the end of the list, we don't to set last anymore
4494          * as it's not needed anymore */
4495         if (last == NULL) {
4496                 assert(first == NULL);
4497                 first = inner_types;
4498         } else {
4499                 last->next = inner_types;
4500         }
4501
4502         return first;
4503 end_error:
4504         return NULL;
4505 }
4506
4507 static void parse_declaration_attributes(entity_t *entity)
4508 {
4509         gnu_attribute_t  *attributes = NULL;
4510         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
4511
4512         if (entity == NULL)
4513                 return;
4514
4515         type_t *type;
4516         if (entity->kind == ENTITY_TYPEDEF) {
4517                 modifiers |= entity->typedefe.modifiers;
4518                 type       = entity->typedefe.type;
4519         } else {
4520                 assert(is_declaration(entity));
4521                 modifiers |= entity->declaration.modifiers;
4522                 type       = entity->declaration.type;
4523         }
4524         if (type == NULL)
4525                 return;
4526
4527         /* handle these strange/stupid mode attributes */
4528         gnu_attribute_t *attribute = attributes;
4529         for ( ; attribute != NULL; attribute = attribute->next) {
4530                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
4531                         continue;
4532
4533                 atomic_type_kind_t  akind = attribute->u.akind;
4534                 if (!is_type_signed(type)) {
4535                         switch (akind) {
4536                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
4537                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
4538                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
4539                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
4540                         default:
4541                                 panic("invalid akind in mode attribute");
4542                         }
4543                 } else {
4544                         switch (akind) {
4545                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_SCHAR; break;
4546                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_SHORT; break;
4547                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_INT; break;
4548                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_LONGLONG; break;
4549                         default:
4550                                 panic("invalid akind in mode attribute");
4551                         }
4552                 }
4553
4554                 type = make_atomic_type(akind, type->base.qualifiers);
4555         }
4556
4557         type_modifiers_t type_modifiers = type->base.modifiers;
4558         if (modifiers & DM_TRANSPARENT_UNION)
4559                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
4560
4561         if (type->base.modifiers != type_modifiers) {
4562                 type_t *copy = duplicate_type(type);
4563                 copy->base.modifiers = type_modifiers;
4564
4565                 type = typehash_insert(copy);
4566                 if (type != copy) {
4567                         obstack_free(type_obst, copy);
4568                 }
4569         }
4570
4571         if (entity->kind == ENTITY_TYPEDEF) {
4572                 entity->typedefe.type      = type;
4573                 entity->typedefe.modifiers = modifiers;
4574         } else {
4575                 entity->declaration.type      = type;
4576                 entity->declaration.modifiers = modifiers;
4577         }
4578 }
4579
4580 static type_t *construct_declarator_type(construct_type_t *construct_list, type_t *type)
4581 {
4582         construct_type_t *iter = construct_list;
4583         for (; iter != NULL; iter = iter->next) {
4584                 switch (iter->kind) {
4585                 case CONSTRUCT_INVALID:
4586                         internal_errorf(HERE, "invalid type construction found");
4587                 case CONSTRUCT_FUNCTION: {
4588                         construct_function_type_t *construct_function_type
4589                                 = (construct_function_type_t*) iter;
4590
4591                         type_t *function_type = construct_function_type->function_type;
4592
4593                         function_type->function.return_type = type;
4594
4595                         type_t *skipped_return_type = skip_typeref(type);
4596                         /* §6.7.5.3(1) */
4597                         if (is_type_function(skipped_return_type)) {
4598                                 errorf(HERE, "function returning function is not allowed");
4599                         } else if (is_type_array(skipped_return_type)) {
4600                                 errorf(HERE, "function returning array is not allowed");
4601                         } else {
4602                                 if (skipped_return_type->base.qualifiers != 0 && warning.other) {
4603                                         warningf(HERE,
4604                                                 "type qualifiers in return type of function type are meaningless");
4605                                 }
4606                         }
4607
4608                         type = function_type;
4609                         break;
4610                 }
4611
4612                 case CONSTRUCT_POINTER: {
4613                         if (is_type_reference(skip_typeref(type)))
4614                                 errorf(HERE, "cannot declare a pointer to reference");
4615
4616                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
4617                         type = make_based_pointer_type(type, parsed_pointer->type_qualifiers, parsed_pointer->base_variable);
4618                         continue;
4619                 }
4620
4621                 case CONSTRUCT_REFERENCE:
4622                         if (is_type_reference(skip_typeref(type)))
4623                                 errorf(HERE, "cannot declare a reference to reference");
4624
4625                         type = make_reference_type(type);
4626                         continue;
4627
4628                 case CONSTRUCT_ARRAY: {
4629                         if (is_type_reference(skip_typeref(type)))
4630                                 errorf(HERE, "cannot declare an array of references");
4631
4632                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
4633                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY);
4634
4635                         expression_t *size_expression = parsed_array->size;
4636                         if (size_expression != NULL) {
4637                                 size_expression
4638                                         = create_implicit_cast(size_expression, type_size_t);
4639                         }
4640
4641                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
4642                         array_type->array.element_type    = type;
4643                         array_type->array.is_static       = parsed_array->is_static;
4644                         array_type->array.is_variable     = parsed_array->is_variable;
4645                         array_type->array.size_expression = size_expression;
4646
4647                         if (size_expression != NULL) {
4648                                 if (is_constant_expression(size_expression)) {
4649                                         array_type->array.size_constant = true;
4650                                         array_type->array.size
4651                                                 = fold_constant(size_expression);
4652                                 } else {
4653                                         array_type->array.is_vla = true;
4654                                 }
4655                         }
4656
4657                         type_t *skipped_type = skip_typeref(type);
4658                         /* §6.7.5.2(1) */
4659                         if (is_type_incomplete(skipped_type)) {
4660                                 errorf(HERE, "array of incomplete type '%T' is not allowed", type);
4661                         } else if (is_type_function(skipped_type)) {
4662                                 errorf(HERE, "array of functions is not allowed");
4663                         }
4664                         type = array_type;
4665                         break;
4666                 }
4667                 }
4668
4669                 type_t *hashed_type = typehash_insert(type);
4670                 if (hashed_type != type) {
4671                         /* the function type was constructed earlier freeing it here will
4672                          * destroy other types... */
4673                         if (iter->kind != CONSTRUCT_FUNCTION) {
4674                                 free_type(type);
4675                         }
4676                         type = hashed_type;
4677                 }
4678         }
4679
4680         return type;
4681 }
4682
4683 static type_t *automatic_type_conversion(type_t *orig_type);
4684
4685 static type_t *semantic_parameter(const source_position_t *pos,
4686                                   type_t *type,
4687                                   const declaration_specifiers_t *specifiers,
4688                                   symbol_t *symbol)
4689 {
4690         /* §6.7.5.3:7  A declaration of a parameter as ``array of type''
4691          *             shall be adjusted to ``qualified pointer to type'',
4692          *             [...]
4693          * §6.7.5.3:8  A declaration of a parameter as ``function returning
4694          *             type'' shall be adjusted to ``pointer to function
4695          *             returning type'', as in 6.3.2.1. */
4696         type = automatic_type_conversion(type);
4697
4698         if (specifiers->is_inline && is_type_valid(type)) {
4699                 errorf(pos, "parameter '%Y' declared 'inline'", symbol);
4700         }
4701
4702         /* §6.9.1:6  The declarations in the declaration list shall contain
4703          *           no storage-class specifier other than register and no
4704          *           initializations. */
4705         if (specifiers->thread_local || (
4706                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4707                         specifiers->storage_class != STORAGE_CLASS_REGISTER)
4708            ) {
4709                 errorf(pos, "invalid storage class for parameter '%Y'", symbol);
4710         }
4711
4712         /* delay test for incomplete type, because we might have (void)
4713          * which is legal but incomplete... */
4714
4715         return type;
4716 }
4717
4718 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
4719                                   declarator_flags_t flags)
4720 {
4721         parse_declarator_env_t env;
4722         memset(&env, 0, sizeof(env));
4723         env.modifiers = specifiers->modifiers;
4724
4725         construct_type_t *construct_type =
4726                 parse_inner_declarator(&env, (flags & DECL_MAY_BE_ABSTRACT) != 0);
4727         type_t           *orig_type      =
4728                 construct_declarator_type(construct_type, specifiers->type);
4729         type_t           *type           = skip_typeref(orig_type);
4730
4731         if (construct_type != NULL) {
4732                 obstack_free(&temp_obst, construct_type);
4733         }
4734
4735         entity_t *entity;
4736         if (specifiers->storage_class == STORAGE_CLASS_TYPEDEF) {
4737                 entity                       = allocate_entity_zero(ENTITY_TYPEDEF);
4738                 entity->base.symbol          = env.symbol;
4739                 entity->base.source_position = env.source_position;
4740                 entity->typedefe.type        = orig_type;
4741
4742                 if (anonymous_entity != NULL) {
4743                         if (is_type_compound(type)) {
4744                                 assert(anonymous_entity->compound.alias == NULL);
4745                                 assert(anonymous_entity->kind == ENTITY_STRUCT ||
4746                                        anonymous_entity->kind == ENTITY_UNION);
4747                                 anonymous_entity->compound.alias = entity;
4748                                 anonymous_entity = NULL;
4749                         } else if (is_type_enum(type)) {
4750                                 assert(anonymous_entity->enume.alias == NULL);
4751                                 assert(anonymous_entity->kind == ENTITY_ENUM);
4752                                 anonymous_entity->enume.alias = entity;
4753                                 anonymous_entity = NULL;
4754                         }
4755                 }
4756         } else {
4757                 /* create a declaration type entity */
4758                 if (flags & DECL_CREATE_COMPOUND_MEMBER) {
4759                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
4760
4761                         if (specifiers->is_inline && is_type_valid(type)) {
4762                                 errorf(&env.source_position,
4763                                                 "compound member '%Y' declared 'inline'", env.symbol);
4764                         }
4765
4766                         if (specifiers->thread_local ||
4767                                 specifiers->storage_class != STORAGE_CLASS_NONE) {
4768                                 errorf(&env.source_position,
4769                                            "compound member '%Y' must have no storage class",
4770                                            env.symbol);
4771                         }
4772                 } else if (flags & DECL_IS_PARAMETER) {
4773                         orig_type = semantic_parameter(&env.source_position, type,
4774                                                        specifiers, env.symbol);
4775
4776                         entity = allocate_entity_zero(ENTITY_PARAMETER);
4777                 } else if (is_type_function(type)) {
4778                         entity = allocate_entity_zero(ENTITY_FUNCTION);
4779
4780                         entity->function.is_inline  = specifiers->is_inline;
4781                         entity->function.parameters = env.parameters;
4782
4783                         if (specifiers->thread_local || (
4784                                         specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4785                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4786                                         specifiers->storage_class != STORAGE_CLASS_STATIC)
4787                            ) {
4788                                 errorf(&env.source_position,
4789                                            "invalid storage class for function '%Y'", env.symbol);
4790                         }
4791                 } else {
4792                         entity = allocate_entity_zero(ENTITY_VARIABLE);
4793
4794                         entity->variable.get_property_sym = specifiers->get_property_sym;
4795                         entity->variable.put_property_sym = specifiers->put_property_sym;
4796                         if (specifiers->alignment != 0) {
4797                                 /* TODO: add checks here */
4798                                 entity->variable.alignment = specifiers->alignment;
4799                         }
4800
4801                         if (specifiers->is_inline && is_type_valid(type)) {
4802                                 errorf(&env.source_position,
4803                                            "variable '%Y' declared 'inline'", env.symbol);
4804                         }
4805
4806                         entity->variable.thread_local = specifiers->thread_local;
4807
4808                         bool invalid_storage_class = false;
4809                         if (current_scope == file_scope) {
4810                                 if (specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4811                                                 specifiers->storage_class != STORAGE_CLASS_NONE   &&
4812                                                 specifiers->storage_class != STORAGE_CLASS_STATIC) {
4813                                         invalid_storage_class = true;
4814                                 }
4815                         } else {
4816                                 if (specifiers->thread_local &&
4817                                                 specifiers->storage_class == STORAGE_CLASS_NONE) {
4818                                         invalid_storage_class = true;
4819                                 }
4820                         }
4821                         if (invalid_storage_class) {
4822                                 errorf(&env.source_position,
4823                                                 "invalid storage class for variable '%Y'", env.symbol);
4824                         }
4825                 }
4826
4827                 entity->base.source_position          = env.source_position;
4828                 entity->base.symbol                   = env.symbol;
4829                 entity->base.namespc                  = NAMESPACE_NORMAL;
4830                 entity->declaration.type              = orig_type;
4831                 entity->declaration.modifiers         = env.modifiers;
4832                 entity->declaration.deprecated_string = specifiers->deprecated_string;
4833
4834                 storage_class_t storage_class = specifiers->storage_class;
4835                 entity->declaration.declared_storage_class = storage_class;
4836
4837                 if (storage_class == STORAGE_CLASS_NONE && current_scope != file_scope)
4838                         storage_class = STORAGE_CLASS_AUTO;
4839                 entity->declaration.storage_class = storage_class;
4840         }
4841
4842         parse_declaration_attributes(entity);
4843
4844         return entity;
4845 }
4846
4847 static type_t *parse_abstract_declarator(type_t *base_type)
4848 {
4849         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4850
4851         type_t *result = construct_declarator_type(construct_type, base_type);
4852         if (construct_type != NULL) {
4853                 obstack_free(&temp_obst, construct_type);
4854         }
4855
4856         return result;
4857 }
4858
4859 /**
4860  * Check if the declaration of main is suspicious.  main should be a
4861  * function with external linkage, returning int, taking either zero
4862  * arguments, two, or three arguments of appropriate types, ie.
4863  *
4864  * int main([ int argc, char **argv [, char **env ] ]).
4865  *
4866  * @param decl    the declaration to check
4867  * @param type    the function type of the declaration
4868  */
4869 static void check_type_of_main(const entity_t *entity)
4870 {
4871         const source_position_t *pos = &entity->base.source_position;
4872         if (entity->kind != ENTITY_FUNCTION) {
4873                 warningf(pos, "'main' is not a function");
4874                 return;
4875         }
4876
4877         if (entity->declaration.storage_class == STORAGE_CLASS_STATIC) {
4878                 warningf(pos, "'main' is normally a non-static function");
4879         }
4880
4881         type_t *type = skip_typeref(entity->declaration.type);
4882         assert(is_type_function(type));
4883
4884         function_type_t *func_type = &type->function;
4885         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4886                 warningf(pos, "return type of 'main' should be 'int', but is '%T'",
4887                          func_type->return_type);
4888         }
4889         const function_parameter_t *parm = func_type->parameters;
4890         if (parm != NULL) {
4891                 type_t *const first_type = parm->type;
4892                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4893                         warningf(pos,
4894                                  "first argument of 'main' should be 'int', but is '%T'",
4895                                  first_type);
4896                 }
4897                 parm = parm->next;
4898                 if (parm != NULL) {
4899                         type_t *const second_type = parm->type;
4900                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4901                                 warningf(pos, "second argument of 'main' should be 'char**', but is '%T'", second_type);
4902                         }
4903                         parm = parm->next;
4904                         if (parm != NULL) {
4905                                 type_t *const third_type = parm->type;
4906                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4907                                         warningf(pos, "third argument of 'main' should be 'char**', but is '%T'", third_type);
4908                                 }
4909                                 parm = parm->next;
4910                                 if (parm != NULL)
4911                                         goto warn_arg_count;
4912                         }
4913                 } else {
4914 warn_arg_count:
4915                         warningf(pos, "'main' takes only zero, two or three arguments");
4916                 }
4917         }
4918 }
4919
4920 /**
4921  * Check if a symbol is the equal to "main".
4922  */
4923 static bool is_sym_main(const symbol_t *const sym)
4924 {
4925         return strcmp(sym->string, "main") == 0;
4926 }
4927
4928 static void error_redefined_as_different_kind(const source_position_t *pos,
4929                 const entity_t *old, entity_kind_t new_kind)
4930 {
4931         errorf(pos, "redeclaration of %s '%Y' as %s (declared %P)",
4932                get_entity_kind_name(old->kind), old->base.symbol,
4933                get_entity_kind_name(new_kind), &old->base.source_position);
4934 }
4935
4936 /**
4937  * record entities for the NAMESPACE_NORMAL, and produce error messages/warnings
4938  * for various problems that occur for multiple definitions
4939  */
4940 static entity_t *record_entity(entity_t *entity, const bool is_definition)
4941 {
4942         const symbol_t *const    symbol  = entity->base.symbol;
4943         const namespace_tag_t    namespc = (namespace_tag_t)entity->base.namespc;
4944         const source_position_t *pos     = &entity->base.source_position;
4945
4946         /* can happen in error cases */
4947         if (symbol == NULL)
4948                 return entity;
4949
4950         entity_t *previous_entity = get_entity(symbol, namespc);
4951         /* pushing the same entity twice will break the stack structure */
4952         assert(previous_entity != entity);
4953
4954         if (entity->kind == ENTITY_FUNCTION) {
4955                 type_t *const orig_type = entity->declaration.type;
4956                 type_t *const type      = skip_typeref(orig_type);
4957
4958                 assert(is_type_function(type));
4959                 if (type->function.unspecified_parameters &&
4960                                 warning.strict_prototypes &&
4961                                 previous_entity == NULL) {
4962                         warningf(pos, "function declaration '%#T' is not a prototype",
4963                                          orig_type, symbol);
4964                 }
4965
4966                 if (warning.main && current_scope == file_scope
4967                                 && is_sym_main(symbol)) {
4968                         check_type_of_main(entity);
4969                 }
4970         }
4971
4972         if (is_declaration(entity) &&
4973                         warning.nested_externs &&
4974                         entity->declaration.storage_class == STORAGE_CLASS_EXTERN &&
4975                         current_scope != file_scope) {
4976                 warningf(pos, "nested extern declaration of '%#T'",
4977                          entity->declaration.type, symbol);
4978         }
4979
4980         if (previous_entity != NULL &&
4981                         previous_entity->base.parent_scope == &current_function->parameters &&
4982                         previous_entity->base.parent_scope->depth + 1 == current_scope->depth) {
4983                 assert(previous_entity->kind == ENTITY_PARAMETER);
4984                 errorf(pos,
4985                        "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
4986                                          entity->declaration.type, symbol,
4987                                          previous_entity->declaration.type, symbol,
4988                                          &previous_entity->base.source_position);
4989                 goto finish;
4990         }
4991
4992         if (previous_entity != NULL &&
4993                         previous_entity->base.parent_scope == current_scope) {
4994                 if (previous_entity->kind != entity->kind) {
4995                         error_redefined_as_different_kind(pos, previous_entity,
4996                                                           entity->kind);
4997                         goto finish;
4998                 }
4999                 if (previous_entity->kind == ENTITY_ENUM_VALUE) {
5000                         errorf(pos, "redeclaration of enum entry '%Y' (declared %P)",
5001                                    symbol, &previous_entity->base.source_position);
5002                         goto finish;
5003                 }
5004                 if (previous_entity->kind == ENTITY_TYPEDEF) {
5005                         /* TODO: C++ allows this for exactly the same type */
5006                         errorf(pos, "redefinition of typedef '%Y' (declared %P)",
5007                                symbol, &previous_entity->base.source_position);
5008                         goto finish;
5009                 }
5010
5011                 /* at this point we should have only VARIABLES or FUNCTIONS */
5012                 assert(is_declaration(previous_entity) && is_declaration(entity));
5013
5014                 declaration_t *const prev_decl = &previous_entity->declaration;
5015                 declaration_t *const decl      = &entity->declaration;
5016
5017                 /* can happen for K&R style declarations */
5018                 if (prev_decl->type       == NULL             &&
5019                                 previous_entity->kind == ENTITY_PARAMETER &&
5020                                 entity->kind          == ENTITY_PARAMETER) {
5021                         prev_decl->type                   = decl->type;
5022                         prev_decl->storage_class          = decl->storage_class;
5023                         prev_decl->declared_storage_class = decl->declared_storage_class;
5024                         prev_decl->modifiers              = decl->modifiers;
5025                         prev_decl->deprecated_string      = decl->deprecated_string;
5026                         return previous_entity;
5027                 }
5028
5029                 type_t *const orig_type = decl->type;
5030                 assert(orig_type != NULL);
5031                 type_t *const type      = skip_typeref(orig_type);
5032                 type_t *      prev_type = skip_typeref(prev_decl->type);
5033
5034                 if (!types_compatible(type, prev_type)) {
5035                         errorf(pos,
5036                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
5037                                    orig_type, symbol, prev_decl->type, symbol,
5038                                    &previous_entity->base.source_position);
5039                 } else {
5040                         unsigned old_storage_class = prev_decl->storage_class;
5041                         if (warning.redundant_decls               &&
5042                                         is_definition                     &&
5043                                         !prev_decl->used                  &&
5044                                         !(prev_decl->modifiers & DM_USED) &&
5045                                         prev_decl->storage_class == STORAGE_CLASS_STATIC) {
5046                                 warningf(&previous_entity->base.source_position,
5047                                          "unnecessary static forward declaration for '%#T'",
5048                                          prev_decl->type, symbol);
5049                         }
5050
5051                         unsigned new_storage_class = decl->storage_class;
5052                         if (is_type_incomplete(prev_type)) {
5053                                 prev_decl->type = type;
5054                                 prev_type       = type;
5055                         }
5056
5057                         /* pretend no storage class means extern for function
5058                          * declarations (except if the previous declaration is neither
5059                          * none nor extern) */
5060                         if (entity->kind == ENTITY_FUNCTION) {
5061                                 if (prev_type->function.unspecified_parameters) {
5062                                         prev_decl->type = type;
5063                                         prev_type       = type;
5064                                 }
5065
5066                                 switch (old_storage_class) {
5067                                 case STORAGE_CLASS_NONE:
5068                                         old_storage_class = STORAGE_CLASS_EXTERN;
5069                                         /* FALLTHROUGH */
5070
5071                                 case STORAGE_CLASS_EXTERN:
5072                                         if (is_definition) {
5073                                                 if (warning.missing_prototypes &&
5074                                                     prev_type->function.unspecified_parameters &&
5075                                                     !is_sym_main(symbol)) {
5076                                                         warningf(pos, "no previous prototype for '%#T'",
5077                                                                          orig_type, symbol);
5078                                                 }
5079                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
5080                                                 new_storage_class = STORAGE_CLASS_EXTERN;
5081                                         }
5082                                         break;
5083
5084                                 default:
5085                                         break;
5086                                 }
5087                         }
5088
5089                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
5090                                         new_storage_class == STORAGE_CLASS_EXTERN) {
5091 warn_redundant_declaration:
5092                                 if (!is_definition           &&
5093                                     warning.redundant_decls  &&
5094                                     is_type_valid(prev_type) &&
5095                                     strcmp(previous_entity->base.source_position.input_name,
5096                                            "<builtin>") != 0) {
5097                                         warningf(pos,
5098                                                  "redundant declaration for '%Y' (declared %P)",
5099                                                  symbol, &previous_entity->base.source_position);
5100                                 }
5101                         } else if (current_function == NULL) {
5102                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
5103                                     new_storage_class == STORAGE_CLASS_STATIC) {
5104                                         errorf(pos,
5105                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
5106                                                symbol, &previous_entity->base.source_position);
5107                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
5108                                         prev_decl->storage_class          = STORAGE_CLASS_NONE;
5109                                         prev_decl->declared_storage_class = STORAGE_CLASS_NONE;
5110                                 } else {
5111                                         /* ISO/IEC 14882:1998(E) §C.1.2:1 */
5112                                         if (c_mode & _CXX)
5113                                                 goto error_redeclaration;
5114                                         goto warn_redundant_declaration;
5115                                 }
5116                         } else if (is_type_valid(prev_type)) {
5117                                 if (old_storage_class == new_storage_class) {
5118 error_redeclaration:
5119                                         errorf(pos, "redeclaration of '%Y' (declared %P)",
5120                                                symbol, &previous_entity->base.source_position);
5121                                 } else {
5122                                         errorf(pos,
5123                                                "redeclaration of '%Y' with different linkage (declared %P)",
5124                                                symbol, &previous_entity->base.source_position);
5125                                 }
5126                         }
5127                 }
5128
5129                 prev_decl->modifiers |= decl->modifiers;
5130                 if (entity->kind == ENTITY_FUNCTION) {
5131                         previous_entity->function.is_inline |= entity->function.is_inline;
5132                 }
5133                 return previous_entity;
5134         }
5135
5136         if (entity->kind == ENTITY_FUNCTION) {
5137                 if (is_definition &&
5138                                 entity->declaration.storage_class != STORAGE_CLASS_STATIC) {
5139                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
5140                                 warningf(pos, "no previous prototype for '%#T'",
5141                                          entity->declaration.type, symbol);
5142                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
5143                                 warningf(pos, "no previous declaration for '%#T'",
5144                                          entity->declaration.type, symbol);
5145                         }
5146                 }
5147         } else if (warning.missing_declarations &&
5148                         entity->kind == ENTITY_VARIABLE &&
5149                         current_scope == file_scope) {
5150                 declaration_t *declaration = &entity->declaration;
5151                 if (declaration->storage_class == STORAGE_CLASS_NONE) {
5152                         warningf(pos, "no previous declaration for '%#T'",
5153                                  declaration->type, symbol);
5154                 }
5155         }
5156
5157 finish:
5158         assert(entity->base.parent_scope == NULL);
5159         assert(current_scope != NULL);
5160
5161         entity->base.parent_scope = current_scope;
5162         entity->base.namespc      = NAMESPACE_NORMAL;
5163         environment_push(entity);
5164         append_entity(current_scope, entity);
5165
5166         return entity;
5167 }
5168
5169 static void parser_error_multiple_definition(entity_t *entity,
5170                 const source_position_t *source_position)
5171 {
5172         errorf(source_position, "multiple definition of symbol '%Y' (declared %P)",
5173                entity->base.symbol, &entity->base.source_position);
5174 }
5175
5176 static bool is_declaration_specifier(const token_t *token,
5177                                      bool only_specifiers_qualifiers)
5178 {
5179         switch (token->type) {
5180                 TYPE_SPECIFIERS
5181                 TYPE_QUALIFIERS
5182                         return true;
5183                 case T_IDENTIFIER:
5184                         return is_typedef_symbol(token->v.symbol);
5185
5186                 case T___extension__:
5187                 STORAGE_CLASSES
5188                         return !only_specifiers_qualifiers;
5189
5190                 default:
5191                         return false;
5192         }
5193 }
5194
5195 static void parse_init_declarator_rest(entity_t *entity)
5196 {
5197         assert(is_declaration(entity));
5198         declaration_t *const declaration = &entity->declaration;
5199
5200         eat('=');
5201
5202         type_t *orig_type = declaration->type;
5203         type_t *type      = skip_typeref(orig_type);
5204
5205         if (entity->kind == ENTITY_VARIABLE
5206                         && entity->variable.initializer != NULL) {
5207                 parser_error_multiple_definition(entity, HERE);
5208         }
5209
5210         bool must_be_constant = false;
5211         if (declaration->storage_class == STORAGE_CLASS_STATIC ||
5212             entity->base.parent_scope  == file_scope) {
5213                 must_be_constant = true;
5214         }
5215
5216         if (is_type_function(type)) {
5217                 errorf(&entity->base.source_position,
5218                        "function '%#T' is initialized like a variable",
5219                        orig_type, entity->base.symbol);
5220                 orig_type = type_error_type;
5221         }
5222
5223         parse_initializer_env_t env;
5224         env.type             = orig_type;
5225         env.must_be_constant = must_be_constant;
5226         env.entity           = entity;
5227         current_init_decl    = entity;
5228
5229         initializer_t *initializer = parse_initializer(&env);
5230         current_init_decl = NULL;
5231
5232         if (entity->kind == ENTITY_VARIABLE) {
5233                 /* § 6.7.5 (22)  array initializers for arrays with unknown size
5234                  * determine the array type size */
5235                 declaration->type            = env.type;
5236                 entity->variable.initializer = initializer;
5237         }
5238 }
5239
5240 /* parse rest of a declaration without any declarator */
5241 static void parse_anonymous_declaration_rest(
5242                 const declaration_specifiers_t *specifiers)
5243 {
5244         eat(';');
5245         anonymous_entity = NULL;
5246
5247         if (warning.other) {
5248                 if (specifiers->storage_class != STORAGE_CLASS_NONE ||
5249                                 specifiers->thread_local) {
5250                         warningf(&specifiers->source_position,
5251                                  "useless storage class in empty declaration");
5252                 }
5253
5254                 type_t *type = specifiers->type;
5255                 switch (type->kind) {
5256                         case TYPE_COMPOUND_STRUCT:
5257                         case TYPE_COMPOUND_UNION: {
5258                                 if (type->compound.compound->base.symbol == NULL) {
5259                                         warningf(&specifiers->source_position,
5260                                                  "unnamed struct/union that defines no instances");
5261                                 }
5262                                 break;
5263                         }
5264
5265                         case TYPE_ENUM:
5266                                 break;
5267
5268                         default:
5269                                 warningf(&specifiers->source_position, "empty declaration");
5270                                 break;
5271                 }
5272         }
5273 }
5274
5275 static void check_variable_type_complete(entity_t *ent)
5276 {
5277         if (ent->kind != ENTITY_VARIABLE)
5278                 return;
5279
5280         /* §6.7:7  If an identifier for an object is declared with no linkage, the
5281          *         type for the object shall be complete [...] */
5282         declaration_t *decl = &ent->declaration;
5283         if (decl->storage_class != STORAGE_CLASS_NONE)
5284                 return;
5285
5286         type_t *const orig_type = decl->type;
5287         type_t *const type      = skip_typeref(orig_type);
5288         if (!is_type_incomplete(type))
5289                 return;
5290
5291         /* GCC allows global arrays without size and assigns them a length of one,
5292          * if no different declaration follows */
5293         if (is_type_array(type) &&
5294                         c_mode & _GNUC      &&
5295                         ent->base.parent_scope == file_scope) {
5296                 ARR_APP1(declaration_t*, incomplete_arrays, decl);
5297                 return;
5298         }
5299
5300         errorf(&ent->base.source_position, "variable '%#T' has incomplete type",
5301                         orig_type, ent->base.symbol);
5302 }
5303
5304
5305 static void parse_declaration_rest(entity_t *ndeclaration,
5306                 const declaration_specifiers_t *specifiers,
5307                 parsed_declaration_func         finished_declaration,
5308                 declarator_flags_t              flags)
5309 {
5310         add_anchor_token(';');
5311         add_anchor_token(',');
5312         while (true) {
5313                 entity_t *entity = finished_declaration(ndeclaration, token.type == '=');
5314
5315                 if (token.type == '=') {
5316                         parse_init_declarator_rest(entity);
5317                 } else if (entity->kind == ENTITY_VARIABLE) {
5318                         /* ISO/IEC 14882:1998(E) §8.5.3:3  The initializer can be omitted
5319                          * [...] where the extern specifier is explicitly used. */
5320                         declaration_t *decl = &entity->declaration;
5321                         if (decl->storage_class != STORAGE_CLASS_EXTERN) {
5322                                 type_t *type = decl->type;
5323                                 if (is_type_reference(skip_typeref(type))) {
5324                                         errorf(&entity->base.source_position,
5325                                                         "reference '%#T' must be initialized",
5326                                                         type, entity->base.symbol);
5327                                 }
5328                         }
5329                 }
5330
5331                 check_variable_type_complete(entity);
5332
5333                 if (token.type != ',')
5334                         break;
5335                 eat(',');
5336
5337                 add_anchor_token('=');
5338                 ndeclaration = parse_declarator(specifiers, flags);
5339                 rem_anchor_token('=');
5340         }
5341         expect(';');
5342
5343 end_error:
5344         anonymous_entity = NULL;
5345         rem_anchor_token(';');
5346         rem_anchor_token(',');
5347 }
5348
5349 static entity_t *finished_kr_declaration(entity_t *entity, bool is_definition)
5350 {
5351         symbol_t *symbol = entity->base.symbol;
5352         if (symbol == NULL) {
5353                 errorf(HERE, "anonymous declaration not valid as function parameter");
5354                 return entity;
5355         }
5356
5357         assert(entity->base.namespc == NAMESPACE_NORMAL);
5358         entity_t *previous_entity = get_entity(symbol, NAMESPACE_NORMAL);
5359         if (previous_entity == NULL
5360                         || previous_entity->base.parent_scope != current_scope) {
5361                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
5362                        symbol);
5363                 return entity;
5364         }
5365
5366         if (is_definition) {
5367                 errorf(HERE, "parameter %Y is initialised", entity->base.symbol);
5368         }
5369
5370         return record_entity(entity, false);
5371 }
5372
5373 static void parse_declaration(parsed_declaration_func finished_declaration,
5374                               declarator_flags_t      flags)
5375 {
5376         declaration_specifiers_t specifiers;
5377         memset(&specifiers, 0, sizeof(specifiers));
5378
5379         add_anchor_token(';');
5380         parse_declaration_specifiers(&specifiers);
5381         rem_anchor_token(';');
5382
5383         if (token.type == ';') {
5384                 parse_anonymous_declaration_rest(&specifiers);
5385         } else {
5386                 entity_t *entity = parse_declarator(&specifiers, flags);
5387                 parse_declaration_rest(entity, &specifiers, finished_declaration, flags);
5388         }
5389 }
5390
5391 static type_t *get_default_promoted_type(type_t *orig_type)
5392 {
5393         type_t *result = orig_type;
5394
5395         type_t *type = skip_typeref(orig_type);
5396         if (is_type_integer(type)) {
5397                 result = promote_integer(type);
5398         } else if (type == type_float) {
5399                 result = type_double;
5400         }
5401
5402         return result;
5403 }
5404
5405 static void parse_kr_declaration_list(entity_t *entity)
5406 {
5407         if (entity->kind != ENTITY_FUNCTION)
5408                 return;
5409
5410         type_t *type = skip_typeref(entity->declaration.type);
5411         assert(is_type_function(type));
5412         if (!type->function.kr_style_parameters)
5413                 return;
5414
5415
5416         add_anchor_token('{');
5417
5418         /* push function parameters */
5419         size_t const  top       = environment_top();
5420         scope_t      *old_scope = scope_push(&entity->function.parameters);
5421
5422         entity_t *parameter = entity->function.parameters.entities;
5423         for ( ; parameter != NULL; parameter = parameter->base.next) {
5424                 assert(parameter->base.parent_scope == NULL);
5425                 parameter->base.parent_scope = current_scope;
5426                 environment_push(parameter);
5427         }
5428
5429         /* parse declaration list */
5430         for (;;) {
5431                 switch (token.type) {
5432                         DECLARATION_START
5433                         case T___extension__:
5434                         /* This covers symbols, which are no type, too, and results in
5435                          * better error messages.  The typical cases are misspelled type
5436                          * names and missing includes. */
5437                         case T_IDENTIFIER:
5438                                 parse_declaration(finished_kr_declaration, DECL_IS_PARAMETER);
5439                                 break;
5440                         default:
5441                                 goto decl_list_end;
5442                 }
5443         }
5444 decl_list_end:
5445
5446         /* pop function parameters */
5447         assert(current_scope == &entity->function.parameters);
5448         scope_pop(old_scope);
5449         environment_pop_to(top);
5450
5451         /* update function type */
5452         type_t *new_type = duplicate_type(type);
5453
5454         function_parameter_t *parameters     = NULL;
5455         function_parameter_t *last_parameter = NULL;
5456
5457         parameter = entity->function.parameters.entities;
5458         for (; parameter != NULL; parameter = parameter->base.next) {
5459                 type_t *parameter_type = parameter->declaration.type;
5460                 if (parameter_type == NULL) {
5461                         if (strict_mode) {
5462                                 errorf(HERE, "no type specified for function parameter '%Y'",
5463                                        parameter->base.symbol);
5464                         } else {
5465                                 if (warning.implicit_int) {
5466                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
5467                                                  parameter->base.symbol);
5468                                 }
5469                                 parameter_type              = type_int;
5470                                 parameter->declaration.type = parameter_type;
5471                         }
5472                 }
5473
5474                 semantic_parameter_incomplete(parameter);
5475                 parameter_type = parameter->declaration.type;
5476
5477                 /*
5478                  * we need the default promoted types for the function type
5479                  */
5480                 parameter_type = get_default_promoted_type(parameter_type);
5481
5482                 function_parameter_t *function_parameter
5483                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
5484                 memset(function_parameter, 0, sizeof(function_parameter[0]));
5485
5486                 function_parameter->type = parameter_type;
5487                 if (last_parameter != NULL) {
5488                         last_parameter->next = function_parameter;
5489                 } else {
5490                         parameters = function_parameter;
5491                 }
5492                 last_parameter = function_parameter;
5493         }
5494
5495         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
5496          * prototype */
5497         new_type->function.parameters             = parameters;
5498         new_type->function.unspecified_parameters = true;
5499
5500         type = typehash_insert(new_type);
5501         if (type != new_type) {
5502                 obstack_free(type_obst, new_type);
5503         }
5504
5505         entity->declaration.type = type;
5506
5507         rem_anchor_token('{');
5508 }
5509
5510 static bool first_err = true;
5511
5512 /**
5513  * When called with first_err set, prints the name of the current function,
5514  * else does noting.
5515  */
5516 static void print_in_function(void)
5517 {
5518         if (first_err) {
5519                 first_err = false;
5520                 diagnosticf("%s: In function '%Y':\n",
5521                             current_function->base.base.source_position.input_name,
5522                             current_function->base.base.symbol);
5523         }
5524 }
5525
5526 /**
5527  * Check if all labels are defined in the current function.
5528  * Check if all labels are used in the current function.
5529  */
5530 static void check_labels(void)
5531 {
5532         for (const goto_statement_t *goto_statement = goto_first;
5533             goto_statement != NULL;
5534             goto_statement = goto_statement->next) {
5535                 /* skip computed gotos */
5536                 if (goto_statement->expression != NULL)
5537                         continue;
5538
5539                 label_t *label = goto_statement->label;
5540
5541                 label->used = true;
5542                 if (label->base.source_position.input_name == NULL) {
5543                         print_in_function();
5544                         errorf(&goto_statement->base.source_position,
5545                                "label '%Y' used but not defined", label->base.symbol);
5546                  }
5547         }
5548
5549         if (warning.unused_label) {
5550                 for (const label_statement_t *label_statement = label_first;
5551                          label_statement != NULL;
5552                          label_statement = label_statement->next) {
5553                         label_t *label = label_statement->label;
5554
5555                         if (! label->used) {
5556                                 print_in_function();
5557                                 warningf(&label_statement->base.source_position,
5558                                          "label '%Y' defined but not used", label->base.symbol);
5559                         }
5560                 }
5561         }
5562 }
5563
5564 static void warn_unused_entity(entity_t *entity, entity_t *end)
5565 {
5566         for (; entity != NULL; entity = entity->base.next) {
5567                 if (!is_declaration(entity))
5568                         continue;
5569
5570                 declaration_t *declaration = &entity->declaration;
5571                 if (declaration->implicit)
5572                         continue;
5573
5574                 if (!declaration->used) {
5575                         print_in_function();
5576                         const char *what = get_entity_kind_name(entity->kind);
5577                         warningf(&entity->base.source_position, "%s '%Y' is unused",
5578                                  what, entity->base.symbol);
5579                 } else if (entity->kind == ENTITY_VARIABLE && !entity->variable.read) {
5580                         print_in_function();
5581                         const char *what = get_entity_kind_name(entity->kind);
5582                         warningf(&entity->base.source_position, "%s '%Y' is never read",
5583                                  what, entity->base.symbol);
5584                 }
5585
5586                 if (entity == end)
5587                         break;
5588         }
5589 }
5590
5591 static void check_unused_variables(statement_t *const stmt, void *const env)
5592 {
5593         (void)env;
5594
5595         switch (stmt->kind) {
5596                 case STATEMENT_DECLARATION: {
5597                         declaration_statement_t const *const decls = &stmt->declaration;
5598                         warn_unused_entity(decls->declarations_begin,
5599                                            decls->declarations_end);
5600                         return;
5601                 }
5602
5603                 case STATEMENT_FOR:
5604                         warn_unused_entity(stmt->fors.scope.entities, NULL);
5605                         return;
5606
5607                 default:
5608                         return;
5609         }
5610 }
5611
5612 /**
5613  * Check declarations of current_function for unused entities.
5614  */
5615 static void check_declarations(void)
5616 {
5617         if (warning.unused_parameter) {
5618                 const scope_t *scope = &current_function->parameters;
5619
5620                 /* do not issue unused warnings for main */
5621                 if (!is_sym_main(current_function->base.base.symbol)) {
5622                         warn_unused_entity(scope->entities, NULL);
5623                 }
5624         }
5625         if (warning.unused_variable) {
5626                 walk_statements(current_function->statement, check_unused_variables,
5627                                 NULL);
5628         }
5629 }
5630
5631 static int determine_truth(expression_t const* const cond)
5632 {
5633         return
5634                 !is_constant_expression(cond) ? 0 :
5635                 fold_constant(cond) != 0      ? 1 :
5636                 -1;
5637 }
5638
5639 static void check_reachable(statement_t *);
5640
5641 static bool expression_returns(expression_t const *const expr)
5642 {
5643         switch (expr->kind) {
5644                 case EXPR_CALL: {
5645                         expression_t const *const func = expr->call.function;
5646                         if (func->kind == EXPR_REFERENCE) {
5647                                 entity_t *entity = func->reference.entity;
5648                                 if (entity->kind == ENTITY_FUNCTION
5649                                                 && entity->declaration.modifiers & DM_NORETURN)
5650                                         return false;
5651                         }
5652
5653                         if (!expression_returns(func))
5654                                 return false;
5655
5656                         for (call_argument_t const* arg = expr->call.arguments; arg != NULL; arg = arg->next) {
5657                                 if (!expression_returns(arg->expression))
5658                                         return false;
5659                         }
5660
5661                         return true;
5662                 }
5663
5664                 case EXPR_REFERENCE:
5665                 case EXPR_REFERENCE_ENUM_VALUE:
5666                 case EXPR_CONST:
5667                 case EXPR_CHARACTER_CONSTANT:
5668                 case EXPR_WIDE_CHARACTER_CONSTANT:
5669                 case EXPR_STRING_LITERAL:
5670                 case EXPR_WIDE_STRING_LITERAL:
5671                 case EXPR_COMPOUND_LITERAL: // TODO descend into initialisers
5672                 case EXPR_LABEL_ADDRESS:
5673                 case EXPR_CLASSIFY_TYPE:
5674                 case EXPR_SIZEOF: // TODO handle obscure VLA case
5675                 case EXPR_ALIGNOF:
5676                 case EXPR_FUNCNAME:
5677                 case EXPR_BUILTIN_SYMBOL:
5678                 case EXPR_BUILTIN_CONSTANT_P:
5679                 case EXPR_BUILTIN_PREFETCH:
5680                 case EXPR_OFFSETOF:
5681                 case EXPR_INVALID:
5682                         return true;
5683
5684                 case EXPR_STATEMENT:
5685                         check_reachable(expr->statement.statement);
5686                         // TODO check if statement can be left
5687                         return true;
5688
5689                 case EXPR_CONDITIONAL:
5690                         // TODO handle constant expression
5691
5692                         if (!expression_returns(expr->conditional.condition))
5693                                 return false;
5694
5695                         if (expr->conditional.true_expression != NULL
5696                                         && expression_returns(expr->conditional.true_expression))
5697                                 return true;
5698
5699                         return expression_returns(expr->conditional.false_expression);
5700
5701                 case EXPR_SELECT:
5702                         return expression_returns(expr->select.compound);
5703
5704                 case EXPR_ARRAY_ACCESS:
5705                         return
5706                                 expression_returns(expr->array_access.array_ref) &&
5707                                 expression_returns(expr->array_access.index);
5708
5709                 case EXPR_VA_START:
5710                         return expression_returns(expr->va_starte.ap);
5711
5712                 case EXPR_VA_ARG:
5713                         return expression_returns(expr->va_arge.ap);
5714
5715                 EXPR_UNARY_CASES_MANDATORY
5716                         return expression_returns(expr->unary.value);
5717
5718                 case EXPR_UNARY_THROW:
5719                         return false;
5720
5721                 EXPR_BINARY_CASES
5722                         // TODO handle constant lhs of && and ||
5723                         return
5724                                 expression_returns(expr->binary.left) &&
5725                                 expression_returns(expr->binary.right);
5726
5727                 case EXPR_UNKNOWN:
5728                         break;
5729         }
5730
5731         panic("unhandled expression");
5732 }
5733
5734 static bool initializer_returns(initializer_t const *const init)
5735 {
5736         switch (init->kind) {
5737                 case INITIALIZER_VALUE:
5738                         return expression_returns(init->value.value);
5739
5740                 case INITIALIZER_LIST: {
5741                         initializer_t * const*       i       = init->list.initializers;
5742                         initializer_t * const* const end     = i + init->list.len;
5743                         bool                         returns = true;
5744                         for (; i != end; ++i) {
5745                                 if (!initializer_returns(*i))
5746                                         returns = false;
5747                         }
5748                         return returns;
5749                 }
5750
5751                 case INITIALIZER_STRING:
5752                 case INITIALIZER_WIDE_STRING:
5753                 case INITIALIZER_DESIGNATOR: // designators have no payload
5754                         return true;
5755         }
5756         panic("unhandled initializer");
5757 }
5758
5759 static bool noreturn_candidate;
5760
5761 static void check_reachable(statement_t *const stmt)
5762 {
5763         if (stmt->base.reachable)
5764                 return;
5765         if (stmt->kind != STATEMENT_DO_WHILE)
5766                 stmt->base.reachable = true;
5767
5768         statement_t *last = stmt;
5769         statement_t *next;
5770         switch (stmt->kind) {
5771                 case STATEMENT_INVALID:
5772                 case STATEMENT_EMPTY:
5773                 case STATEMENT_LOCAL_LABEL:
5774                 case STATEMENT_ASM:
5775                         next = stmt->base.next;
5776                         break;
5777
5778                 case STATEMENT_DECLARATION: {
5779                         declaration_statement_t const *const decl = &stmt->declaration;
5780                         entity_t                const *      ent  = decl->declarations_begin;
5781                         entity_t                const *const last = decl->declarations_end;
5782                         if (ent != NULL) {
5783                                 for (;; ent = ent->base.next) {
5784                                         if (ent->kind                 == ENTITY_VARIABLE &&
5785                                                         ent->variable.initializer != NULL            &&
5786                                                         !initializer_returns(ent->variable.initializer)) {
5787                                                 return;
5788                                         }
5789                                         if (ent == last)
5790                                                 break;
5791                                 }
5792                         }
5793                         next = stmt->base.next;
5794                         break;
5795                 }
5796
5797                 case STATEMENT_COMPOUND:
5798                         next = stmt->compound.statements;
5799                         break;
5800
5801                 case STATEMENT_RETURN: {
5802                         expression_t const *const val = stmt->returns.value;
5803                         if (val == NULL || expression_returns(val))
5804                                 noreturn_candidate = false;
5805                         return;
5806                 }
5807
5808                 case STATEMENT_IF: {
5809                         if_statement_t const *const ifs  = &stmt->ifs;
5810                         expression_t   const *const cond = ifs->condition;
5811
5812                         if (!expression_returns(cond))
5813                                 return;
5814
5815                         int const val = determine_truth(cond);
5816
5817                         if (val >= 0)
5818                                 check_reachable(ifs->true_statement);
5819
5820                         if (val > 0)
5821                                 return;
5822
5823                         if (ifs->false_statement != NULL) {
5824                                 check_reachable(ifs->false_statement);
5825                                 return;
5826                         }
5827
5828                         next = stmt->base.next;
5829                         break;
5830                 }
5831
5832                 case STATEMENT_SWITCH: {
5833                         switch_statement_t const *const switchs = &stmt->switchs;
5834                         expression_t       const *const expr    = switchs->expression;
5835
5836                         if (!expression_returns(expr))
5837                                 return;
5838
5839                         if (is_constant_expression(expr)) {
5840                                 long                    const val      = fold_constant(expr);
5841                                 case_label_statement_t *      defaults = NULL;
5842                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5843                                         if (i->expression == NULL) {
5844                                                 defaults = i;
5845                                                 continue;
5846                                         }
5847
5848                                         if (i->first_case <= val && val <= i->last_case) {
5849                                                 check_reachable((statement_t*)i);
5850                                                 return;
5851                                         }
5852                                 }
5853
5854                                 if (defaults != NULL) {
5855                                         check_reachable((statement_t*)defaults);
5856                                         return;
5857                                 }
5858                         } else {
5859                                 bool has_default = false;
5860                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5861                                         if (i->expression == NULL)
5862                                                 has_default = true;
5863
5864                                         check_reachable((statement_t*)i);
5865                                 }
5866
5867                                 if (has_default)
5868                                         return;
5869                         }
5870
5871                         next = stmt->base.next;
5872                         break;
5873                 }
5874
5875                 case STATEMENT_EXPRESSION: {
5876                         /* Check for noreturn function call */
5877                         expression_t const *const expr = stmt->expression.expression;
5878                         if (!expression_returns(expr))
5879                                 return;
5880
5881                         next = stmt->base.next;
5882                         break;
5883                 }
5884
5885                 case STATEMENT_CONTINUE: {
5886                         statement_t *parent = stmt;
5887                         for (;;) {
5888                                 parent = parent->base.parent;
5889                                 if (parent == NULL) /* continue not within loop */
5890                                         return;
5891
5892                                 next = parent;
5893                                 switch (parent->kind) {
5894                                         case STATEMENT_WHILE:    goto continue_while;
5895                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5896                                         case STATEMENT_FOR:      goto continue_for;
5897
5898                                         default: break;
5899                                 }
5900                         }
5901                 }
5902
5903                 case STATEMENT_BREAK: {
5904                         statement_t *parent = stmt;
5905                         for (;;) {
5906                                 parent = parent->base.parent;
5907                                 if (parent == NULL) /* break not within loop/switch */
5908                                         return;
5909
5910                                 switch (parent->kind) {
5911                                         case STATEMENT_SWITCH:
5912                                         case STATEMENT_WHILE:
5913                                         case STATEMENT_DO_WHILE:
5914                                         case STATEMENT_FOR:
5915                                                 last = parent;
5916                                                 next = parent->base.next;
5917                                                 goto found_break_parent;
5918
5919                                         default: break;
5920                                 }
5921                         }
5922 found_break_parent:
5923                         break;
5924                 }
5925
5926                 case STATEMENT_GOTO:
5927                         if (stmt->gotos.expression) {
5928                                 if (!expression_returns(stmt->gotos.expression))
5929                                         return;
5930
5931                                 statement_t *parent = stmt->base.parent;
5932                                 if (parent == NULL) /* top level goto */
5933                                         return;
5934                                 next = parent;
5935                         } else {
5936                                 next = stmt->gotos.label->statement;
5937                                 if (next == NULL) /* missing label */
5938                                         return;
5939                         }
5940                         break;
5941
5942                 case STATEMENT_LABEL:
5943                         next = stmt->label.statement;
5944                         break;
5945
5946                 case STATEMENT_CASE_LABEL:
5947                         next = stmt->case_label.statement;
5948                         break;
5949
5950                 case STATEMENT_WHILE: {
5951                         while_statement_t const *const whiles = &stmt->whiles;
5952                         expression_t      const *const cond   = whiles->condition;
5953
5954                         if (!expression_returns(cond))
5955                                 return;
5956
5957                         int const val = determine_truth(cond);
5958
5959                         if (val >= 0)
5960                                 check_reachable(whiles->body);
5961
5962                         if (val > 0)
5963                                 return;
5964
5965                         next = stmt->base.next;
5966                         break;
5967                 }
5968
5969                 case STATEMENT_DO_WHILE:
5970                         next = stmt->do_while.body;
5971                         break;
5972
5973                 case STATEMENT_FOR: {
5974                         for_statement_t *const fors = &stmt->fors;
5975
5976                         if (fors->condition_reachable)
5977                                 return;
5978                         fors->condition_reachable = true;
5979
5980                         expression_t const *const cond = fors->condition;
5981
5982                         int val;
5983                         if (cond == NULL) {
5984                                 val = 1;
5985                         } else if (expression_returns(cond)) {
5986                                 val = determine_truth(cond);
5987                         } else {
5988                                 return;
5989                         }
5990
5991                         if (val >= 0)
5992                                 check_reachable(fors->body);
5993
5994                         if (val > 0)
5995                                 return;
5996
5997                         next = stmt->base.next;
5998                         break;
5999                 }
6000
6001                 case STATEMENT_MS_TRY: {
6002                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
6003                         check_reachable(ms_try->try_statement);
6004                         next = ms_try->final_statement;
6005                         break;
6006                 }
6007
6008                 case STATEMENT_LEAVE: {
6009                         statement_t *parent = stmt;
6010                         for (;;) {
6011                                 parent = parent->base.parent;
6012                                 if (parent == NULL) /* __leave not within __try */
6013                                         return;
6014
6015                                 if (parent->kind == STATEMENT_MS_TRY) {
6016                                         last = parent;
6017                                         next = parent->ms_try.final_statement;
6018                                         break;
6019                                 }
6020                         }
6021                         break;
6022                 }
6023         }
6024
6025         while (next == NULL) {
6026                 next = last->base.parent;
6027                 if (next == NULL) {
6028                         noreturn_candidate = false;
6029
6030                         type_t *const type = current_function->base.type;
6031                         assert(is_type_function(type));
6032                         type_t *const ret  = skip_typeref(type->function.return_type);
6033                         if (warning.return_type                    &&
6034                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
6035                             is_type_valid(ret)                     &&
6036                             !is_sym_main(current_function->base.base.symbol)) {
6037                                 warningf(&stmt->base.source_position,
6038                                          "control reaches end of non-void function");
6039                         }
6040                         return;
6041                 }
6042
6043                 switch (next->kind) {
6044                         case STATEMENT_INVALID:
6045                         case STATEMENT_EMPTY:
6046                         case STATEMENT_DECLARATION:
6047                         case STATEMENT_LOCAL_LABEL:
6048                         case STATEMENT_EXPRESSION:
6049                         case STATEMENT_ASM:
6050                         case STATEMENT_RETURN:
6051                         case STATEMENT_CONTINUE:
6052                         case STATEMENT_BREAK:
6053                         case STATEMENT_GOTO:
6054                         case STATEMENT_LEAVE:
6055                                 panic("invalid control flow in function");
6056
6057                         case STATEMENT_COMPOUND:
6058                         case STATEMENT_IF:
6059                         case STATEMENT_SWITCH:
6060                         case STATEMENT_LABEL:
6061                         case STATEMENT_CASE_LABEL:
6062                                 last = next;
6063                                 next = next->base.next;
6064                                 break;
6065
6066                         case STATEMENT_WHILE: {
6067 continue_while:
6068                                 if (next->base.reachable)
6069                                         return;
6070                                 next->base.reachable = true;
6071
6072                                 while_statement_t const *const whiles = &next->whiles;
6073                                 expression_t      const *const cond   = whiles->condition;
6074
6075                                 if (!expression_returns(cond))
6076                                         return;
6077
6078                                 int const val = determine_truth(cond);
6079
6080                                 if (val >= 0)
6081                                         check_reachable(whiles->body);
6082
6083                                 if (val > 0)
6084                                         return;
6085
6086                                 last = next;
6087                                 next = next->base.next;
6088                                 break;
6089                         }
6090
6091                         case STATEMENT_DO_WHILE: {
6092 continue_do_while:
6093                                 if (next->base.reachable)
6094                                         return;
6095                                 next->base.reachable = true;
6096
6097                                 do_while_statement_t const *const dw   = &next->do_while;
6098                                 expression_t         const *const cond = dw->condition;
6099
6100                                 if (!expression_returns(cond))
6101                                         return;
6102
6103                                 int const val = determine_truth(cond);
6104
6105                                 if (val >= 0)
6106                                         check_reachable(dw->body);
6107
6108                                 if (val > 0)
6109                                         return;
6110
6111                                 last = next;
6112                                 next = next->base.next;
6113                                 break;
6114                         }
6115
6116                         case STATEMENT_FOR: {
6117 continue_for:;
6118                                 for_statement_t *const fors = &next->fors;
6119
6120                                 fors->step_reachable = true;
6121
6122                                 if (fors->condition_reachable)
6123                                         return;
6124                                 fors->condition_reachable = true;
6125
6126                                 expression_t const *const cond = fors->condition;
6127
6128                                 int val;
6129                                 if (cond == NULL) {
6130                                         val = 1;
6131                                 } else if (expression_returns(cond)) {
6132                                         val = determine_truth(cond);
6133                                 } else {
6134                                         return;
6135                                 }
6136
6137                                 if (val >= 0)
6138                                         check_reachable(fors->body);
6139
6140                                 if (val > 0)
6141                                         return;
6142
6143                                 last = next;
6144                                 next = next->base.next;
6145                                 break;
6146                         }
6147
6148                         case STATEMENT_MS_TRY:
6149                                 last = next;
6150                                 next = next->ms_try.final_statement;
6151                                 break;
6152                 }
6153         }
6154
6155         check_reachable(next);
6156 }
6157
6158 static void check_unreachable(statement_t* const stmt, void *const env)
6159 {
6160         (void)env;
6161
6162         switch (stmt->kind) {
6163                 case STATEMENT_DO_WHILE:
6164                         if (!stmt->base.reachable) {
6165                                 expression_t const *const cond = stmt->do_while.condition;
6166                                 if (determine_truth(cond) >= 0) {
6167                                         warningf(&cond->base.source_position,
6168                                                  "condition of do-while-loop is unreachable");
6169                                 }
6170                         }
6171                         return;
6172
6173                 case STATEMENT_FOR: {
6174                         for_statement_t const* const fors = &stmt->fors;
6175
6176                         // if init and step are unreachable, cond is unreachable, too
6177                         if (!stmt->base.reachable && !fors->step_reachable) {
6178                                 warningf(&stmt->base.source_position, "statement is unreachable");
6179                         } else {
6180                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
6181                                         warningf(&fors->initialisation->base.source_position,
6182                                                  "initialisation of for-statement is unreachable");
6183                                 }
6184
6185                                 if (!fors->condition_reachable && fors->condition != NULL) {
6186                                         warningf(&fors->condition->base.source_position,
6187                                                  "condition of for-statement is unreachable");
6188                                 }
6189
6190                                 if (!fors->step_reachable && fors->step != NULL) {
6191                                         warningf(&fors->step->base.source_position,
6192                                                  "step of for-statement is unreachable");
6193                                 }
6194                         }
6195                         return;
6196                 }
6197
6198                 case STATEMENT_COMPOUND:
6199                         if (stmt->compound.statements != NULL)
6200                                 return;
6201                         goto warn_unreachable;
6202
6203                 case STATEMENT_DECLARATION: {
6204                         /* Only warn if there is at least one declarator with an initializer.
6205                          * This typically occurs in switch statements. */
6206                         declaration_statement_t const *const decl = &stmt->declaration;
6207                         entity_t                const *      ent  = decl->declarations_begin;
6208                         entity_t                const *const last = decl->declarations_end;
6209                         for (;; ent = ent->base.next) {
6210                                 if (ent->kind                 == ENTITY_VARIABLE &&
6211                                                 ent->variable.initializer != NULL) {
6212                                         goto warn_unreachable;
6213                                 }
6214                                 if (ent == last)
6215                                         return;
6216                         }
6217                 }
6218
6219                 default:
6220 warn_unreachable:
6221                         if (!stmt->base.reachable)
6222                                 warningf(&stmt->base.source_position, "statement is unreachable");
6223                         return;
6224         }
6225 }
6226
6227 static void parse_external_declaration(void)
6228 {
6229         /* function-definitions and declarations both start with declaration
6230          * specifiers */
6231         declaration_specifiers_t specifiers;
6232         memset(&specifiers, 0, sizeof(specifiers));
6233
6234         add_anchor_token(';');
6235         parse_declaration_specifiers(&specifiers);
6236         rem_anchor_token(';');
6237
6238         /* must be a declaration */
6239         if (token.type == ';') {
6240                 parse_anonymous_declaration_rest(&specifiers);
6241                 return;
6242         }
6243
6244         add_anchor_token(',');
6245         add_anchor_token('=');
6246         add_anchor_token(';');
6247         add_anchor_token('{');
6248
6249         /* declarator is common to both function-definitions and declarations */
6250         entity_t *ndeclaration = parse_declarator(&specifiers, DECL_FLAGS_NONE);
6251
6252         rem_anchor_token('{');
6253         rem_anchor_token(';');
6254         rem_anchor_token('=');
6255         rem_anchor_token(',');
6256
6257         /* must be a declaration */
6258         switch (token.type) {
6259                 case ',':
6260                 case ';':
6261                 case '=':
6262                         parse_declaration_rest(ndeclaration, &specifiers, record_entity,
6263                                         DECL_FLAGS_NONE);
6264                         return;
6265         }
6266
6267         /* must be a function definition */
6268         parse_kr_declaration_list(ndeclaration);
6269
6270         if (token.type != '{') {
6271                 parse_error_expected("while parsing function definition", '{', NULL);
6272                 eat_until_matching_token(';');
6273                 return;
6274         }
6275
6276         assert(is_declaration(ndeclaration));
6277         type_t *type = skip_typeref(ndeclaration->declaration.type);
6278
6279         if (!is_type_function(type)) {
6280                 if (is_type_valid(type)) {
6281                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
6282                                type, ndeclaration->base.symbol);
6283                 }
6284                 eat_block();
6285                 return;
6286         }
6287
6288         if (warning.aggregate_return &&
6289             is_type_compound(skip_typeref(type->function.return_type))) {
6290                 warningf(HERE, "function '%Y' returns an aggregate",
6291                          ndeclaration->base.symbol);
6292         }
6293         if (warning.traditional && !type->function.unspecified_parameters) {
6294                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
6295                         ndeclaration->base.symbol);
6296         }
6297         if (warning.old_style_definition && type->function.unspecified_parameters) {
6298                 warningf(HERE, "old-style function definition '%Y'",
6299                         ndeclaration->base.symbol);
6300         }
6301
6302         /* § 6.7.5.3 (14) a function definition with () means no
6303          * parameters (and not unspecified parameters) */
6304         if (type->function.unspecified_parameters
6305                         && type->function.parameters == NULL
6306                         && !type->function.kr_style_parameters) {
6307                 type_t *duplicate = duplicate_type(type);
6308                 duplicate->function.unspecified_parameters = false;
6309
6310                 type = typehash_insert(duplicate);
6311                 if (type != duplicate) {
6312                         obstack_free(type_obst, duplicate);
6313                 }
6314                 ndeclaration->declaration.type = type;
6315         }
6316
6317         entity_t *const entity = record_entity(ndeclaration, true);
6318         assert(entity->kind == ENTITY_FUNCTION);
6319         assert(ndeclaration->kind == ENTITY_FUNCTION);
6320
6321         function_t *function = &entity->function;
6322         if (ndeclaration != entity) {
6323                 function->parameters = ndeclaration->function.parameters;
6324         }
6325         assert(is_declaration(entity));
6326         type = skip_typeref(entity->declaration.type);
6327
6328         /* push function parameters and switch scope */
6329         size_t const  top       = environment_top();
6330         scope_t      *old_scope = scope_push(&function->parameters);
6331
6332         entity_t *parameter = function->parameters.entities;
6333         for (; parameter != NULL; parameter = parameter->base.next) {
6334                 if (parameter->base.parent_scope == &ndeclaration->function.parameters) {
6335                         parameter->base.parent_scope = current_scope;
6336                 }
6337                 assert(parameter->base.parent_scope == NULL
6338                                 || parameter->base.parent_scope == current_scope);
6339                 parameter->base.parent_scope = current_scope;
6340                 if (parameter->base.symbol == NULL) {
6341                         errorf(&parameter->base.source_position, "parameter name omitted");
6342                         continue;
6343                 }
6344                 environment_push(parameter);
6345         }
6346
6347         if (function->statement != NULL) {
6348                 parser_error_multiple_definition(entity, HERE);
6349                 eat_block();
6350         } else {
6351                 /* parse function body */
6352                 int         label_stack_top      = label_top();
6353                 function_t *old_current_function = current_function;
6354                 current_function                 = function;
6355                 current_parent                   = NULL;
6356
6357                 goto_first   = NULL;
6358                 goto_anchor  = &goto_first;
6359                 label_first  = NULL;
6360                 label_anchor = &label_first;
6361
6362                 statement_t *const body = parse_compound_statement(false);
6363                 function->statement = body;
6364                 first_err = true;
6365                 check_labels();
6366                 check_declarations();
6367                 if (warning.return_type      ||
6368                     warning.unreachable_code ||
6369                     (warning.missing_noreturn
6370                      && !(function->base.modifiers & DM_NORETURN))) {
6371                         noreturn_candidate = true;
6372                         check_reachable(body);
6373                         if (warning.unreachable_code)
6374                                 walk_statements(body, check_unreachable, NULL);
6375                         if (warning.missing_noreturn &&
6376                             noreturn_candidate       &&
6377                             !(function->base.modifiers & DM_NORETURN)) {
6378                                 warningf(&body->base.source_position,
6379                                          "function '%#T' is candidate for attribute 'noreturn'",
6380                                          type, entity->base.symbol);
6381                         }
6382                 }
6383
6384                 assert(current_parent   == NULL);
6385                 assert(current_function == function);
6386                 current_function = old_current_function;
6387                 label_pop_to(label_stack_top);
6388         }
6389
6390         assert(current_scope == &function->parameters);
6391         scope_pop(old_scope);
6392         environment_pop_to(top);
6393 }
6394
6395 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
6396                                   source_position_t *source_position,
6397                                   const symbol_t *symbol)
6398 {
6399         type_t *type = allocate_type_zero(TYPE_BITFIELD);
6400
6401         type->bitfield.base_type       = base_type;
6402         type->bitfield.size_expression = size;
6403
6404         il_size_t bit_size;
6405         type_t *skipped_type = skip_typeref(base_type);
6406         if (!is_type_integer(skipped_type)) {
6407                 errorf(HERE, "bitfield base type '%T' is not an integer type",
6408                         base_type);
6409                 bit_size = 0;
6410         } else {
6411                 bit_size = skipped_type->base.size * 8;
6412         }
6413
6414         if (is_constant_expression(size)) {
6415                 long v = fold_constant(size);
6416
6417                 if (v < 0) {
6418                         errorf(source_position, "negative width in bit-field '%Y'", symbol);
6419                 } else if (v == 0) {
6420                         errorf(source_position, "zero width for bit-field '%Y'", symbol);
6421                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
6422                         errorf(source_position, "width of '%Y' exceeds its type", symbol);
6423                 } else {
6424                         type->bitfield.bit_size = v;
6425                 }
6426         }
6427
6428         return type;
6429 }
6430
6431 static entity_t *find_compound_entry(compound_t *compound, symbol_t *symbol)
6432 {
6433         entity_t *iter = compound->members.entities;
6434         for (; iter != NULL; iter = iter->base.next) {
6435                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
6436                         continue;
6437
6438                 if (iter->base.symbol == symbol) {
6439                         return iter;
6440                 } else if (iter->base.symbol == NULL) {
6441                         type_t *type = skip_typeref(iter->declaration.type);
6442                         if (is_type_compound(type)) {
6443                                 entity_t *result
6444                                         = find_compound_entry(type->compound.compound, symbol);
6445                                 if (result != NULL)
6446                                         return result;
6447                         }
6448                         continue;
6449                 }
6450         }
6451
6452         return NULL;
6453 }
6454
6455 static void parse_compound_declarators(compound_t *compound,
6456                 const declaration_specifiers_t *specifiers)
6457 {
6458         while (true) {
6459                 entity_t *entity;
6460
6461                 if (token.type == ':') {
6462                         source_position_t source_position = *HERE;
6463                         next_token();
6464
6465                         type_t *base_type = specifiers->type;
6466                         expression_t *size = parse_constant_expression();
6467
6468                         type_t *type = make_bitfield_type(base_type, size,
6469                                         &source_position, sym_anonymous);
6470
6471                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
6472                         entity->base.namespc                       = NAMESPACE_NORMAL;
6473                         entity->base.source_position               = source_position;
6474                         entity->declaration.declared_storage_class = STORAGE_CLASS_NONE;
6475                         entity->declaration.storage_class          = STORAGE_CLASS_NONE;
6476                         entity->declaration.modifiers              = specifiers->modifiers;
6477                         entity->declaration.type                   = type;
6478                 } else {
6479                         entity = parse_declarator(specifiers,
6480                                         DECL_MAY_BE_ABSTRACT | DECL_CREATE_COMPOUND_MEMBER);
6481                         assert(entity->kind == ENTITY_COMPOUND_MEMBER);
6482
6483                         if (token.type == ':') {
6484                                 source_position_t source_position = *HERE;
6485                                 next_token();
6486                                 expression_t *size = parse_constant_expression();
6487
6488                                 type_t *type = entity->declaration.type;
6489                                 type_t *bitfield_type = make_bitfield_type(type, size,
6490                                                 &source_position, entity->base.symbol);
6491                                 entity->declaration.type = bitfield_type;
6492                         }
6493                 }
6494
6495                 /* make sure we don't define a symbol multiple times */
6496                 symbol_t *symbol = entity->base.symbol;
6497                 if (symbol != NULL) {
6498                         entity_t *prev = find_compound_entry(compound, symbol);
6499
6500                         if (prev != NULL) {
6501                                 errorf(&entity->base.source_position,
6502                                        "multiple declarations of symbol '%Y' (declared %P)",
6503                                        symbol, &prev->base.source_position);
6504                         }
6505                 }
6506
6507                 append_entity(&compound->members, entity);
6508
6509                 type_t *orig_type = entity->declaration.type;
6510                 type_t *type      = skip_typeref(orig_type);
6511                 if (is_type_function(type)) {
6512                         errorf(&entity->base.source_position,
6513                                         "compound member '%Y' must not have function type '%T'",
6514                                         entity->base.symbol, orig_type);
6515                 } else if (is_type_incomplete(type)) {
6516                         /* §6.7.2.1:16 flexible array member */
6517                         if (is_type_array(type) &&
6518                                         token.type == ';'   &&
6519                                         look_ahead(1)->type == '}') {
6520                                 compound->has_flexible_member = true;
6521                         } else {
6522                                 errorf(&entity->base.source_position,
6523                                                 "compound member '%Y' has incomplete type '%T'",
6524                                                 entity->base.symbol, orig_type);
6525                         }
6526                 }
6527
6528                 if (token.type != ',')
6529                         break;
6530                 next_token();
6531         }
6532         expect(';');
6533
6534 end_error:
6535         anonymous_entity = NULL;
6536 }
6537
6538 static void parse_compound_type_entries(compound_t *compound)
6539 {
6540         eat('{');
6541         add_anchor_token('}');
6542
6543         while (token.type != '}') {
6544                 if (token.type == T_EOF) {
6545                         errorf(HERE, "EOF while parsing struct");
6546                         break;
6547                 }
6548                 declaration_specifiers_t specifiers;
6549                 memset(&specifiers, 0, sizeof(specifiers));
6550                 parse_declaration_specifiers(&specifiers);
6551
6552                 parse_compound_declarators(compound, &specifiers);
6553         }
6554         rem_anchor_token('}');
6555         next_token();
6556
6557         /* §6.7.2.1:7 */
6558         compound->complete = true;
6559 }
6560
6561 static type_t *parse_typename(void)
6562 {
6563         declaration_specifiers_t specifiers;
6564         memset(&specifiers, 0, sizeof(specifiers));
6565         parse_declaration_specifiers(&specifiers);
6566         if (specifiers.storage_class != STORAGE_CLASS_NONE ||
6567                         specifiers.thread_local) {
6568                 /* TODO: improve error message, user does probably not know what a
6569                  * storage class is...
6570                  */
6571                 errorf(HERE, "typename may not have a storage class");
6572         }
6573
6574         type_t *result = parse_abstract_declarator(specifiers.type);
6575
6576         return result;
6577 }
6578
6579
6580
6581
6582 typedef expression_t* (*parse_expression_function)(void);
6583 typedef expression_t* (*parse_expression_infix_function)(expression_t *left);
6584
6585 typedef struct expression_parser_function_t expression_parser_function_t;
6586 struct expression_parser_function_t {
6587         parse_expression_function        parser;
6588         unsigned                         infix_precedence;
6589         parse_expression_infix_function  infix_parser;
6590 };
6591
6592 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
6593
6594 /**
6595  * Prints an error message if an expression was expected but not read
6596  */
6597 static expression_t *expected_expression_error(void)
6598 {
6599         /* skip the error message if the error token was read */
6600         if (token.type != T_ERROR) {
6601                 errorf(HERE, "expected expression, got token %K", &token);
6602         }
6603         next_token();
6604
6605         return create_invalid_expression();
6606 }
6607
6608 /**
6609  * Parse a string constant.
6610  */
6611 static expression_t *parse_string_const(void)
6612 {
6613         wide_string_t wres;
6614         if (token.type == T_STRING_LITERAL) {
6615                 string_t res = token.v.string;
6616                 next_token();
6617                 while (token.type == T_STRING_LITERAL) {
6618                         res = concat_strings(&res, &token.v.string);
6619                         next_token();
6620                 }
6621                 if (token.type != T_WIDE_STRING_LITERAL) {
6622                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
6623                         /* note: that we use type_char_ptr here, which is already the
6624                          * automatic converted type. revert_automatic_type_conversion
6625                          * will construct the array type */
6626                         cnst->base.type    = warning.write_strings ? type_const_char_ptr : type_char_ptr;
6627                         cnst->string.value = res;
6628                         return cnst;
6629                 }
6630
6631                 wres = concat_string_wide_string(&res, &token.v.wide_string);
6632         } else {
6633                 wres = token.v.wide_string;
6634         }
6635         next_token();
6636
6637         for (;;) {
6638                 switch (token.type) {
6639                         case T_WIDE_STRING_LITERAL:
6640                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
6641                                 break;
6642
6643                         case T_STRING_LITERAL:
6644                                 wres = concat_wide_string_string(&wres, &token.v.string);
6645                                 break;
6646
6647                         default: {
6648                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
6649                                 cnst->base.type         = warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
6650                                 cnst->wide_string.value = wres;
6651                                 return cnst;
6652                         }
6653                 }
6654                 next_token();
6655         }
6656 }
6657
6658 /**
6659  * Parse a boolean constant.
6660  */
6661 static expression_t *parse_bool_const(bool value)
6662 {
6663         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6664         cnst->base.type          = type_bool;
6665         cnst->conste.v.int_value = value;
6666
6667         next_token();
6668
6669         return cnst;
6670 }
6671
6672 /**
6673  * Parse an integer constant.
6674  */
6675 static expression_t *parse_int_const(void)
6676 {
6677         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6678         cnst->base.type          = token.datatype;
6679         cnst->conste.v.int_value = token.v.intvalue;
6680
6681         next_token();
6682
6683         return cnst;
6684 }
6685
6686 /**
6687  * Parse a character constant.
6688  */
6689 static expression_t *parse_character_constant(void)
6690 {
6691         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
6692         cnst->base.type          = token.datatype;
6693         cnst->conste.v.character = token.v.string;
6694
6695         if (cnst->conste.v.character.size != 1) {
6696                 if (!GNU_MODE) {
6697                         errorf(HERE, "more than 1 character in character constant");
6698                 } else if (warning.multichar) {
6699                         warningf(HERE, "multi-character character constant");
6700                 }
6701         }
6702         next_token();
6703
6704         return cnst;
6705 }
6706
6707 /**
6708  * Parse a wide character constant.
6709  */
6710 static expression_t *parse_wide_character_constant(void)
6711 {
6712         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
6713         cnst->base.type               = token.datatype;
6714         cnst->conste.v.wide_character = token.v.wide_string;
6715
6716         if (cnst->conste.v.wide_character.size != 1) {
6717                 if (!GNU_MODE) {
6718                         errorf(HERE, "more than 1 character in character constant");
6719                 } else if (warning.multichar) {
6720                         warningf(HERE, "multi-character character constant");
6721                 }
6722         }
6723         next_token();
6724
6725         return cnst;
6726 }
6727
6728 /**
6729  * Parse a float constant.
6730  */
6731 static expression_t *parse_float_const(void)
6732 {
6733         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6734         cnst->base.type            = token.datatype;
6735         cnst->conste.v.float_value = token.v.floatvalue;
6736
6737         next_token();
6738
6739         return cnst;
6740 }
6741
6742 static entity_t *create_implicit_function(symbol_t *symbol,
6743                 const source_position_t *source_position)
6744 {
6745         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION);
6746         ntype->function.return_type            = type_int;
6747         ntype->function.unspecified_parameters = true;
6748
6749         type_t *type = typehash_insert(ntype);
6750         if (type != ntype) {
6751                 free_type(ntype);
6752         }
6753
6754         entity_t *entity = allocate_entity_zero(ENTITY_FUNCTION);
6755         entity->declaration.storage_class          = STORAGE_CLASS_EXTERN;
6756         entity->declaration.declared_storage_class = STORAGE_CLASS_EXTERN;
6757         entity->declaration.type                   = type;
6758         entity->declaration.implicit               = true;
6759         entity->base.symbol                        = symbol;
6760         entity->base.source_position               = *source_position;
6761
6762         bool strict_prototypes_old = warning.strict_prototypes;
6763         warning.strict_prototypes  = false;
6764         record_entity(entity, false);
6765         warning.strict_prototypes = strict_prototypes_old;
6766
6767         return entity;
6768 }
6769
6770 /**
6771  * Creates a return_type (func)(argument_type) function type if not
6772  * already exists.
6773  */
6774 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
6775                                     type_t *argument_type2)
6776 {
6777         function_parameter_t *parameter2
6778                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
6779         memset(parameter2, 0, sizeof(parameter2[0]));
6780         parameter2->type = argument_type2;
6781
6782         function_parameter_t *parameter1
6783                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
6784         memset(parameter1, 0, sizeof(parameter1[0]));
6785         parameter1->type = argument_type1;
6786         parameter1->next = parameter2;
6787
6788         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6789         type->function.return_type = return_type;
6790         type->function.parameters  = parameter1;
6791
6792         type_t *result = typehash_insert(type);
6793         if (result != type) {
6794                 free_type(type);
6795         }
6796
6797         return result;
6798 }
6799
6800 /**
6801  * Creates a return_type (func)(argument_type) function type if not
6802  * already exists.
6803  *
6804  * @param return_type    the return type
6805  * @param argument_type  the argument type
6806  */
6807 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
6808 {
6809         function_parameter_t *parameter
6810                 = obstack_alloc(type_obst, sizeof(parameter[0]));
6811         memset(parameter, 0, sizeof(parameter[0]));
6812         parameter->type = argument_type;
6813
6814         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6815         type->function.return_type = return_type;
6816         type->function.parameters  = parameter;
6817
6818         type_t *result = typehash_insert(type);
6819         if (result != type) {
6820                 free_type(type);
6821         }
6822
6823         return result;
6824 }
6825
6826 static type_t *make_function_0_type(type_t *return_type)
6827 {
6828         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6829         type->function.return_type = return_type;
6830         type->function.parameters  = NULL;
6831
6832         type_t *result = typehash_insert(type);
6833         if (result != type) {
6834                 free_type(type);
6835         }
6836
6837         return result;
6838 }
6839
6840 /**
6841  * Creates a function type for some function like builtins.
6842  *
6843  * @param symbol   the symbol describing the builtin
6844  */
6845 static type_t *get_builtin_symbol_type(symbol_t *symbol)
6846 {
6847         switch (symbol->ID) {
6848         case T___builtin_alloca:
6849                 return make_function_1_type(type_void_ptr, type_size_t);
6850         case T___builtin_huge_val:
6851                 return make_function_0_type(type_double);
6852         case T___builtin_inf:
6853                 return make_function_0_type(type_double);
6854         case T___builtin_inff:
6855                 return make_function_0_type(type_float);
6856         case T___builtin_infl:
6857                 return make_function_0_type(type_long_double);
6858         case T___builtin_nan:
6859                 return make_function_1_type(type_double, type_char_ptr);
6860         case T___builtin_nanf:
6861                 return make_function_1_type(type_float, type_char_ptr);
6862         case T___builtin_nanl:
6863                 return make_function_1_type(type_long_double, type_char_ptr);
6864         case T___builtin_va_end:
6865                 return make_function_1_type(type_void, type_valist);
6866         case T___builtin_expect:
6867                 return make_function_2_type(type_long, type_long, type_long);
6868         default:
6869                 internal_errorf(HERE, "not implemented builtin symbol found");
6870         }
6871 }
6872
6873 /**
6874  * Performs automatic type cast as described in § 6.3.2.1.
6875  *
6876  * @param orig_type  the original type
6877  */
6878 static type_t *automatic_type_conversion(type_t *orig_type)
6879 {
6880         type_t *type = skip_typeref(orig_type);
6881         if (is_type_array(type)) {
6882                 array_type_t *array_type   = &type->array;
6883                 type_t       *element_type = array_type->element_type;
6884                 unsigned      qualifiers   = array_type->base.qualifiers;
6885
6886                 return make_pointer_type(element_type, qualifiers);
6887         }
6888
6889         if (is_type_function(type)) {
6890                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6891         }
6892
6893         return orig_type;
6894 }
6895
6896 /**
6897  * reverts the automatic casts of array to pointer types and function
6898  * to function-pointer types as defined § 6.3.2.1
6899  */
6900 type_t *revert_automatic_type_conversion(const expression_t *expression)
6901 {
6902         switch (expression->kind) {
6903                 case EXPR_REFERENCE: {
6904                         entity_t *entity = expression->reference.entity;
6905                         if (is_declaration(entity)) {
6906                                 return entity->declaration.type;
6907                         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6908                                 return entity->enum_value.enum_type;
6909                         } else {
6910                                 panic("no declaration or enum in reference");
6911                         }
6912                 }
6913
6914                 case EXPR_SELECT: {
6915                         entity_t *entity = expression->select.compound_entry;
6916                         assert(is_declaration(entity));
6917                         type_t   *type   = entity->declaration.type;
6918                         return get_qualified_type(type,
6919                                                   expression->base.type->base.qualifiers);
6920                 }
6921
6922                 case EXPR_UNARY_DEREFERENCE: {
6923                         const expression_t *const value = expression->unary.value;
6924                         type_t             *const type  = skip_typeref(value->base.type);
6925                         assert(is_type_pointer(type));
6926                         return type->pointer.points_to;
6927                 }
6928
6929                 case EXPR_BUILTIN_SYMBOL:
6930                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
6931
6932                 case EXPR_ARRAY_ACCESS: {
6933                         const expression_t *array_ref = expression->array_access.array_ref;
6934                         type_t             *type_left = skip_typeref(array_ref->base.type);
6935                         if (!is_type_valid(type_left))
6936                                 return type_left;
6937                         assert(is_type_pointer(type_left));
6938                         return type_left->pointer.points_to;
6939                 }
6940
6941                 case EXPR_STRING_LITERAL: {
6942                         size_t size = expression->string.value.size;
6943                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
6944                 }
6945
6946                 case EXPR_WIDE_STRING_LITERAL: {
6947                         size_t size = expression->wide_string.value.size;
6948                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
6949                 }
6950
6951                 case EXPR_COMPOUND_LITERAL:
6952                         return expression->compound_literal.type;
6953
6954                 default: break;
6955         }
6956
6957         return expression->base.type;
6958 }
6959
6960 static expression_t *parse_reference(void)
6961 {
6962         symbol_t *const symbol = token.v.symbol;
6963
6964         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
6965
6966         if (entity == NULL) {
6967                 if (!strict_mode && look_ahead(1)->type == '(') {
6968                         /* an implicitly declared function */
6969                         if (warning.implicit_function_declaration) {
6970                                 warningf(HERE, "implicit declaration of function '%Y'",
6971                                         symbol);
6972                         }
6973
6974                         entity = create_implicit_function(symbol, HERE);
6975                 } else {
6976                         errorf(HERE, "unknown symbol '%Y' found.", symbol);
6977                         entity = create_error_entity(symbol, ENTITY_VARIABLE);
6978                 }
6979         }
6980
6981         type_t *orig_type;
6982
6983         if (is_declaration(entity)) {
6984                 orig_type = entity->declaration.type;
6985         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6986                 orig_type = entity->enum_value.enum_type;
6987         } else if (entity->kind == ENTITY_TYPEDEF) {
6988                 errorf(HERE, "encountered typedef name '%Y' while parsing expression",
6989                         symbol);
6990                 next_token();
6991                 return create_invalid_expression();
6992         } else {
6993                 panic("expected declaration or enum value in reference");
6994         }
6995
6996         /* we always do the auto-type conversions; the & and sizeof parser contains
6997          * code to revert this! */
6998         type_t *type = automatic_type_conversion(orig_type);
6999
7000         expression_kind_t kind = EXPR_REFERENCE;
7001         if (entity->kind == ENTITY_ENUM_VALUE)
7002                 kind = EXPR_REFERENCE_ENUM_VALUE;
7003
7004         expression_t *expression     = allocate_expression_zero(kind);
7005         expression->reference.entity = entity;
7006         expression->base.type        = type;
7007
7008         /* this declaration is used */
7009         if (is_declaration(entity)) {
7010                 entity->declaration.used = true;
7011         }
7012
7013         if (entity->base.parent_scope != file_scope
7014                 && entity->base.parent_scope->depth < current_function->parameters.depth
7015                 && is_type_valid(orig_type) && !is_type_function(orig_type)) {
7016                 if (entity->kind == ENTITY_VARIABLE) {
7017                         /* access of a variable from an outer function */
7018                         entity->variable.address_taken = true;
7019                 } else if (entity->kind == ENTITY_PARAMETER) {
7020                         entity->parameter.address_taken = true;
7021                 }
7022                 current_function->need_closure = true;
7023         }
7024
7025         /* check for deprecated functions */
7026         if (warning.deprecated_declarations
7027                 && is_declaration(entity)
7028                 && entity->declaration.modifiers & DM_DEPRECATED) {
7029                 declaration_t *declaration = &entity->declaration;
7030
7031                 char const *const prefix = entity->kind == ENTITY_FUNCTION ?
7032                         "function" : "variable";
7033
7034                 if (declaration->deprecated_string != NULL) {
7035                         warningf(HERE, "%s '%Y' is deprecated (declared %P): \"%s\"",
7036                                  prefix, entity->base.symbol, &entity->base.source_position,
7037                                  declaration->deprecated_string);
7038                 } else {
7039                         warningf(HERE, "%s '%Y' is deprecated (declared %P)", prefix,
7040                                  entity->base.symbol, &entity->base.source_position);
7041                 }
7042         }
7043
7044         if (warning.init_self && entity == current_init_decl && !in_type_prop
7045             && entity->kind == ENTITY_VARIABLE) {
7046                 current_init_decl = NULL;
7047                 warningf(HERE, "variable '%#T' is initialized by itself",
7048                          entity->declaration.type, entity->base.symbol);
7049         }
7050
7051         next_token();
7052         return expression;
7053 }
7054
7055 static bool semantic_cast(expression_t *cast)
7056 {
7057         expression_t            *expression      = cast->unary.value;
7058         type_t                  *orig_dest_type  = cast->base.type;
7059         type_t                  *orig_type_right = expression->base.type;
7060         type_t            const *dst_type        = skip_typeref(orig_dest_type);
7061         type_t            const *src_type        = skip_typeref(orig_type_right);
7062         source_position_t const *pos             = &cast->base.source_position;
7063
7064         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
7065         if (dst_type == type_void)
7066                 return true;
7067
7068         /* only integer and pointer can be casted to pointer */
7069         if (is_type_pointer(dst_type)  &&
7070             !is_type_pointer(src_type) &&
7071             !is_type_integer(src_type) &&
7072             is_type_valid(src_type)) {
7073                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
7074                 return false;
7075         }
7076
7077         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
7078                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
7079                 return false;
7080         }
7081
7082         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
7083                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
7084                 return false;
7085         }
7086
7087         if (warning.cast_qual &&
7088             is_type_pointer(src_type) &&
7089             is_type_pointer(dst_type)) {
7090                 type_t *src = skip_typeref(src_type->pointer.points_to);
7091                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
7092                 unsigned missing_qualifiers =
7093                         src->base.qualifiers & ~dst->base.qualifiers;
7094                 if (missing_qualifiers != 0) {
7095                         warningf(pos,
7096                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
7097                                  missing_qualifiers, orig_type_right);
7098                 }
7099         }
7100         return true;
7101 }
7102
7103 static expression_t *parse_compound_literal(type_t *type)
7104 {
7105         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
7106
7107         parse_initializer_env_t env;
7108         env.type             = type;
7109         env.entity           = NULL;
7110         env.must_be_constant = false;
7111         initializer_t *initializer = parse_initializer(&env);
7112         type = env.type;
7113
7114         expression->compound_literal.initializer = initializer;
7115         expression->compound_literal.type        = type;
7116         expression->base.type                    = automatic_type_conversion(type);
7117
7118         return expression;
7119 }
7120
7121 /**
7122  * Parse a cast expression.
7123  */
7124 static expression_t *parse_cast(void)
7125 {
7126         add_anchor_token(')');
7127
7128         source_position_t source_position = token.source_position;
7129
7130         type_t *type = parse_typename();
7131
7132         rem_anchor_token(')');
7133         expect(')');
7134
7135         if (token.type == '{') {
7136                 return parse_compound_literal(type);
7137         }
7138
7139         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
7140         cast->base.source_position = source_position;
7141
7142         expression_t *value = parse_sub_expression(PREC_CAST);
7143         cast->base.type   = type;
7144         cast->unary.value = value;
7145
7146         if (! semantic_cast(cast)) {
7147                 /* TODO: record the error in the AST. else it is impossible to detect it */
7148         }
7149
7150         return cast;
7151 end_error:
7152         return create_invalid_expression();
7153 }
7154
7155 /**
7156  * Parse a statement expression.
7157  */
7158 static expression_t *parse_statement_expression(void)
7159 {
7160         add_anchor_token(')');
7161
7162         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
7163
7164         statement_t *statement          = parse_compound_statement(true);
7165         expression->statement.statement = statement;
7166
7167         /* find last statement and use its type */
7168         type_t *type = type_void;
7169         const statement_t *stmt = statement->compound.statements;
7170         if (stmt != NULL) {
7171                 while (stmt->base.next != NULL)
7172                         stmt = stmt->base.next;
7173
7174                 if (stmt->kind == STATEMENT_EXPRESSION) {
7175                         type = stmt->expression.expression->base.type;
7176                 }
7177         } else if (warning.other) {
7178                 warningf(&expression->base.source_position, "empty statement expression ({})");
7179         }
7180         expression->base.type = type;
7181
7182         rem_anchor_token(')');
7183         expect(')');
7184
7185 end_error:
7186         return expression;
7187 }
7188
7189 /**
7190  * Parse a parenthesized expression.
7191  */
7192 static expression_t *parse_parenthesized_expression(void)
7193 {
7194         eat('(');
7195
7196         switch (token.type) {
7197         case '{':
7198                 /* gcc extension: a statement expression */
7199                 return parse_statement_expression();
7200
7201         TYPE_QUALIFIERS
7202         TYPE_SPECIFIERS
7203                 return parse_cast();
7204         case T_IDENTIFIER:
7205                 if (is_typedef_symbol(token.v.symbol)) {
7206                         return parse_cast();
7207                 }
7208         }
7209
7210         add_anchor_token(')');
7211         expression_t *result = parse_expression();
7212         rem_anchor_token(')');
7213         expect(')');
7214
7215 end_error:
7216         return result;
7217 }
7218
7219 static expression_t *parse_function_keyword(void)
7220 {
7221         /* TODO */
7222
7223         if (current_function == NULL) {
7224                 errorf(HERE, "'__func__' used outside of a function");
7225         }
7226
7227         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7228         expression->base.type     = type_char_ptr;
7229         expression->funcname.kind = FUNCNAME_FUNCTION;
7230
7231         next_token();
7232
7233         return expression;
7234 }
7235
7236 static expression_t *parse_pretty_function_keyword(void)
7237 {
7238         if (current_function == NULL) {
7239                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
7240         }
7241
7242         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7243         expression->base.type     = type_char_ptr;
7244         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
7245
7246         eat(T___PRETTY_FUNCTION__);
7247
7248         return expression;
7249 }
7250
7251 static expression_t *parse_funcsig_keyword(void)
7252 {
7253         if (current_function == NULL) {
7254                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
7255         }
7256
7257         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7258         expression->base.type     = type_char_ptr;
7259         expression->funcname.kind = FUNCNAME_FUNCSIG;
7260
7261         eat(T___FUNCSIG__);
7262
7263         return expression;
7264 }
7265
7266 static expression_t *parse_funcdname_keyword(void)
7267 {
7268         if (current_function == NULL) {
7269                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
7270         }
7271
7272         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7273         expression->base.type     = type_char_ptr;
7274         expression->funcname.kind = FUNCNAME_FUNCDNAME;
7275
7276         eat(T___FUNCDNAME__);
7277
7278         return expression;
7279 }
7280
7281 static designator_t *parse_designator(void)
7282 {
7283         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
7284         result->source_position = *HERE;
7285
7286         if (token.type != T_IDENTIFIER) {
7287                 parse_error_expected("while parsing member designator",
7288                                      T_IDENTIFIER, NULL);
7289                 return NULL;
7290         }
7291         result->symbol = token.v.symbol;
7292         next_token();
7293
7294         designator_t *last_designator = result;
7295         while (true) {
7296                 if (token.type == '.') {
7297                         next_token();
7298                         if (token.type != T_IDENTIFIER) {
7299                                 parse_error_expected("while parsing member designator",
7300                                                      T_IDENTIFIER, NULL);
7301                                 return NULL;
7302                         }
7303                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7304                         designator->source_position = *HERE;
7305                         designator->symbol          = token.v.symbol;
7306                         next_token();
7307
7308                         last_designator->next = designator;
7309                         last_designator       = designator;
7310                         continue;
7311                 }
7312                 if (token.type == '[') {
7313                         next_token();
7314                         add_anchor_token(']');
7315                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7316                         designator->source_position = *HERE;
7317                         designator->array_index     = parse_expression();
7318                         rem_anchor_token(']');
7319                         expect(']');
7320                         if (designator->array_index == NULL) {
7321                                 return NULL;
7322                         }
7323
7324                         last_designator->next = designator;
7325                         last_designator       = designator;
7326                         continue;
7327                 }
7328                 break;
7329         }
7330
7331         return result;
7332 end_error:
7333         return NULL;
7334 }
7335
7336 /**
7337  * Parse the __builtin_offsetof() expression.
7338  */
7339 static expression_t *parse_offsetof(void)
7340 {
7341         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
7342         expression->base.type    = type_size_t;
7343
7344         eat(T___builtin_offsetof);
7345
7346         expect('(');
7347         add_anchor_token(',');
7348         type_t *type = parse_typename();
7349         rem_anchor_token(',');
7350         expect(',');
7351         add_anchor_token(')');
7352         designator_t *designator = parse_designator();
7353         rem_anchor_token(')');
7354         expect(')');
7355
7356         expression->offsetofe.type       = type;
7357         expression->offsetofe.designator = designator;
7358
7359         type_path_t path;
7360         memset(&path, 0, sizeof(path));
7361         path.top_type = type;
7362         path.path     = NEW_ARR_F(type_path_entry_t, 0);
7363
7364         descend_into_subtype(&path);
7365
7366         if (!walk_designator(&path, designator, true)) {
7367                 return create_invalid_expression();
7368         }
7369
7370         DEL_ARR_F(path.path);
7371
7372         return expression;
7373 end_error:
7374         return create_invalid_expression();
7375 }
7376
7377 /**
7378  * Parses a _builtin_va_start() expression.
7379  */
7380 static expression_t *parse_va_start(void)
7381 {
7382         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
7383
7384         eat(T___builtin_va_start);
7385
7386         expect('(');
7387         add_anchor_token(',');
7388         expression->va_starte.ap = parse_assignment_expression();
7389         rem_anchor_token(',');
7390         expect(',');
7391         expression_t *const expr = parse_assignment_expression();
7392         if (expr->kind == EXPR_REFERENCE) {
7393                 entity_t *const entity = expr->reference.entity;
7394                 if (entity->base.parent_scope != &current_function->parameters
7395                                 || entity->base.next != NULL
7396                                 || entity->kind != ENTITY_PARAMETER) {
7397                         errorf(&expr->base.source_position,
7398                                "second argument of 'va_start' must be last parameter of the current function");
7399                 } else {
7400                         expression->va_starte.parameter = &entity->variable;
7401                 }
7402                 expect(')');
7403                 return expression;
7404         }
7405         expect(')');
7406 end_error:
7407         return create_invalid_expression();
7408 }
7409
7410 /**
7411  * Parses a _builtin_va_arg() expression.
7412  */
7413 static expression_t *parse_va_arg(void)
7414 {
7415         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
7416
7417         eat(T___builtin_va_arg);
7418
7419         expect('(');
7420         expression->va_arge.ap = parse_assignment_expression();
7421         expect(',');
7422         expression->base.type = parse_typename();
7423         expect(')');
7424
7425         return expression;
7426 end_error:
7427         return create_invalid_expression();
7428 }
7429
7430 static expression_t *parse_builtin_symbol(void)
7431 {
7432         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
7433
7434         symbol_t *symbol = token.v.symbol;
7435
7436         expression->builtin_symbol.symbol = symbol;
7437         next_token();
7438
7439         type_t *type = get_builtin_symbol_type(symbol);
7440         type = automatic_type_conversion(type);
7441
7442         expression->base.type = type;
7443         return expression;
7444 }
7445
7446 /**
7447  * Parses a __builtin_constant() expression.
7448  */
7449 static expression_t *parse_builtin_constant(void)
7450 {
7451         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
7452
7453         eat(T___builtin_constant_p);
7454
7455         expect('(');
7456         add_anchor_token(')');
7457         expression->builtin_constant.value = parse_assignment_expression();
7458         rem_anchor_token(')');
7459         expect(')');
7460         expression->base.type = type_int;
7461
7462         return expression;
7463 end_error:
7464         return create_invalid_expression();
7465 }
7466
7467 /**
7468  * Parses a __builtin_prefetch() expression.
7469  */
7470 static expression_t *parse_builtin_prefetch(void)
7471 {
7472         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
7473
7474         eat(T___builtin_prefetch);
7475
7476         expect('(');
7477         add_anchor_token(')');
7478         expression->builtin_prefetch.adr = parse_assignment_expression();
7479         if (token.type == ',') {
7480                 next_token();
7481                 expression->builtin_prefetch.rw = parse_assignment_expression();
7482         }
7483         if (token.type == ',') {
7484                 next_token();
7485                 expression->builtin_prefetch.locality = parse_assignment_expression();
7486         }
7487         rem_anchor_token(')');
7488         expect(')');
7489         expression->base.type = type_void;
7490
7491         return expression;
7492 end_error:
7493         return create_invalid_expression();
7494 }
7495
7496 /**
7497  * Parses a __builtin_is_*() compare expression.
7498  */
7499 static expression_t *parse_compare_builtin(void)
7500 {
7501         expression_t *expression;
7502
7503         switch (token.type) {
7504         case T___builtin_isgreater:
7505                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
7506                 break;
7507         case T___builtin_isgreaterequal:
7508                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
7509                 break;
7510         case T___builtin_isless:
7511                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
7512                 break;
7513         case T___builtin_islessequal:
7514                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
7515                 break;
7516         case T___builtin_islessgreater:
7517                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
7518                 break;
7519         case T___builtin_isunordered:
7520                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
7521                 break;
7522         default:
7523                 internal_errorf(HERE, "invalid compare builtin found");
7524         }
7525         expression->base.source_position = *HERE;
7526         next_token();
7527
7528         expect('(');
7529         expression->binary.left = parse_assignment_expression();
7530         expect(',');
7531         expression->binary.right = parse_assignment_expression();
7532         expect(')');
7533
7534         type_t *const orig_type_left  = expression->binary.left->base.type;
7535         type_t *const orig_type_right = expression->binary.right->base.type;
7536
7537         type_t *const type_left  = skip_typeref(orig_type_left);
7538         type_t *const type_right = skip_typeref(orig_type_right);
7539         if (!is_type_float(type_left) && !is_type_float(type_right)) {
7540                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7541                         type_error_incompatible("invalid operands in comparison",
7542                                 &expression->base.source_position, orig_type_left, orig_type_right);
7543                 }
7544         } else {
7545                 semantic_comparison(&expression->binary);
7546         }
7547
7548         return expression;
7549 end_error:
7550         return create_invalid_expression();
7551 }
7552
7553 #if 0
7554 /**
7555  * Parses a __builtin_expect() expression.
7556  */
7557 static expression_t *parse_builtin_expect(void)
7558 {
7559         expression_t *expression
7560                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
7561
7562         eat(T___builtin_expect);
7563
7564         expect('(');
7565         expression->binary.left = parse_assignment_expression();
7566         expect(',');
7567         expression->binary.right = parse_constant_expression();
7568         expect(')');
7569
7570         expression->base.type = expression->binary.left->base.type;
7571
7572         return expression;
7573 end_error:
7574         return create_invalid_expression();
7575 }
7576 #endif
7577
7578 /**
7579  * Parses a MS assume() expression.
7580  */
7581 static expression_t *parse_assume(void)
7582 {
7583         expression_t *expression = allocate_expression_zero(EXPR_UNARY_ASSUME);
7584
7585         eat(T__assume);
7586
7587         expect('(');
7588         add_anchor_token(')');
7589         expression->unary.value = parse_assignment_expression();
7590         rem_anchor_token(')');
7591         expect(')');
7592
7593         expression->base.type = type_void;
7594         return expression;
7595 end_error:
7596         return create_invalid_expression();
7597 }
7598
7599 /**
7600  * Return the declaration for a given label symbol or create a new one.
7601  *
7602  * @param symbol  the symbol of the label
7603  */
7604 static label_t *get_label(symbol_t *symbol)
7605 {
7606         entity_t *label;
7607         assert(current_function != NULL);
7608
7609         label = get_entity(symbol, NAMESPACE_LABEL);
7610         /* if we found a local label, we already created the declaration */
7611         if (label != NULL && label->kind == ENTITY_LOCAL_LABEL) {
7612                 if (label->base.parent_scope != current_scope) {
7613                         assert(label->base.parent_scope->depth < current_scope->depth);
7614                         current_function->goto_to_outer = true;
7615                 }
7616                 return &label->label;
7617         }
7618
7619         label = get_entity(symbol, NAMESPACE_LABEL);
7620         /* if we found a label in the same function, then we already created the
7621          * declaration */
7622         if (label != NULL
7623                         && label->base.parent_scope == &current_function->parameters) {
7624                 return &label->label;
7625         }
7626
7627         /* otherwise we need to create a new one */
7628         label               = allocate_entity_zero(ENTITY_LABEL);
7629         label->base.namespc = NAMESPACE_LABEL;
7630         label->base.symbol  = symbol;
7631
7632         label_push(label);
7633
7634         return &label->label;
7635 }
7636
7637 /**
7638  * Parses a GNU && label address expression.
7639  */
7640 static expression_t *parse_label_address(void)
7641 {
7642         source_position_t source_position = token.source_position;
7643         eat(T_ANDAND);
7644         if (token.type != T_IDENTIFIER) {
7645                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
7646                 goto end_error;
7647         }
7648         symbol_t *symbol = token.v.symbol;
7649         next_token();
7650
7651         label_t *label       = get_label(symbol);
7652         label->used          = true;
7653         label->address_taken = true;
7654
7655         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
7656         expression->base.source_position = source_position;
7657
7658         /* label address is threaten as a void pointer */
7659         expression->base.type           = type_void_ptr;
7660         expression->label_address.label = label;
7661         return expression;
7662 end_error:
7663         return create_invalid_expression();
7664 }
7665
7666 /**
7667  * Parse a microsoft __noop expression.
7668  */
7669 static expression_t *parse_noop_expression(void)
7670 {
7671         /* the result is a (int)0 */
7672         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
7673         cnst->base.type            = type_int;
7674         cnst->conste.v.int_value   = 0;
7675         cnst->conste.is_ms_noop    = true;
7676
7677         eat(T___noop);
7678
7679         if (token.type == '(') {
7680                 /* parse arguments */
7681                 eat('(');
7682                 add_anchor_token(')');
7683                 add_anchor_token(',');
7684
7685                 if (token.type != ')') {
7686                         while (true) {
7687                                 (void)parse_assignment_expression();
7688                                 if (token.type != ',')
7689                                         break;
7690                                 next_token();
7691                         }
7692                 }
7693         }
7694         rem_anchor_token(',');
7695         rem_anchor_token(')');
7696         expect(')');
7697
7698 end_error:
7699         return cnst;
7700 }
7701
7702 /**
7703  * Parses a primary expression.
7704  */
7705 static expression_t *parse_primary_expression(void)
7706 {
7707         switch (token.type) {
7708                 case T_false:                    return parse_bool_const(false);
7709                 case T_true:                     return parse_bool_const(true);
7710                 case T_INTEGER:                  return parse_int_const();
7711                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
7712                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
7713                 case T_FLOATINGPOINT:            return parse_float_const();
7714                 case T_STRING_LITERAL:
7715                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
7716                 case T_IDENTIFIER:               return parse_reference();
7717                 case T___FUNCTION__:
7718                 case T___func__:                 return parse_function_keyword();
7719                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
7720                 case T___FUNCSIG__:              return parse_funcsig_keyword();
7721                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
7722                 case T___builtin_offsetof:       return parse_offsetof();
7723                 case T___builtin_va_start:       return parse_va_start();
7724                 case T___builtin_va_arg:         return parse_va_arg();
7725                 case T___builtin_expect:
7726                 case T___builtin_alloca:
7727                 case T___builtin_inf:
7728                 case T___builtin_inff:
7729                 case T___builtin_infl:
7730                 case T___builtin_nan:
7731                 case T___builtin_nanf:
7732                 case T___builtin_nanl:
7733                 case T___builtin_huge_val:
7734                 case T___builtin_va_end:         return parse_builtin_symbol();
7735                 case T___builtin_isgreater:
7736                 case T___builtin_isgreaterequal:
7737                 case T___builtin_isless:
7738                 case T___builtin_islessequal:
7739                 case T___builtin_islessgreater:
7740                 case T___builtin_isunordered:    return parse_compare_builtin();
7741                 case T___builtin_constant_p:     return parse_builtin_constant();
7742                 case T___builtin_prefetch:       return parse_builtin_prefetch();
7743                 case T__assume:                  return parse_assume();
7744                 case T_ANDAND:
7745                         if (GNU_MODE)
7746                                 return parse_label_address();
7747                         break;
7748
7749                 case '(':                        return parse_parenthesized_expression();
7750                 case T___noop:                   return parse_noop_expression();
7751         }
7752
7753         errorf(HERE, "unexpected token %K, expected an expression", &token);
7754         return create_invalid_expression();
7755 }
7756
7757 /**
7758  * Check if the expression has the character type and issue a warning then.
7759  */
7760 static void check_for_char_index_type(const expression_t *expression)
7761 {
7762         type_t       *const type      = expression->base.type;
7763         const type_t *const base_type = skip_typeref(type);
7764
7765         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
7766                         warning.char_subscripts) {
7767                 warningf(&expression->base.source_position,
7768                          "array subscript has type '%T'", type);
7769         }
7770 }
7771
7772 static expression_t *parse_array_expression(expression_t *left)
7773 {
7774         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
7775
7776         eat('[');
7777         add_anchor_token(']');
7778
7779         expression_t *inside = parse_expression();
7780
7781         type_t *const orig_type_left   = left->base.type;
7782         type_t *const orig_type_inside = inside->base.type;
7783
7784         type_t *const type_left   = skip_typeref(orig_type_left);
7785         type_t *const type_inside = skip_typeref(orig_type_inside);
7786
7787         type_t                    *return_type;
7788         array_access_expression_t *array_access = &expression->array_access;
7789         if (is_type_pointer(type_left)) {
7790                 return_type             = type_left->pointer.points_to;
7791                 array_access->array_ref = left;
7792                 array_access->index     = inside;
7793                 check_for_char_index_type(inside);
7794         } else if (is_type_pointer(type_inside)) {
7795                 return_type             = type_inside->pointer.points_to;
7796                 array_access->array_ref = inside;
7797                 array_access->index     = left;
7798                 array_access->flipped   = true;
7799                 check_for_char_index_type(left);
7800         } else {
7801                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
7802                         errorf(HERE,
7803                                 "array access on object with non-pointer types '%T', '%T'",
7804                                 orig_type_left, orig_type_inside);
7805                 }
7806                 return_type             = type_error_type;
7807                 array_access->array_ref = left;
7808                 array_access->index     = inside;
7809         }
7810
7811         expression->base.type = automatic_type_conversion(return_type);
7812
7813         rem_anchor_token(']');
7814         expect(']');
7815 end_error:
7816         return expression;
7817 }
7818
7819 static expression_t *parse_typeprop(expression_kind_t const kind)
7820 {
7821         expression_t  *tp_expression = allocate_expression_zero(kind);
7822         tp_expression->base.type     = type_size_t;
7823
7824         eat(kind == EXPR_SIZEOF ? T_sizeof : T___alignof__);
7825
7826         /* we only refer to a type property, mark this case */
7827         bool old     = in_type_prop;
7828         in_type_prop = true;
7829
7830         type_t       *orig_type;
7831         expression_t *expression;
7832         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
7833                 next_token();
7834                 add_anchor_token(')');
7835                 orig_type = parse_typename();
7836                 rem_anchor_token(')');
7837                 expect(')');
7838
7839                 if (token.type == '{') {
7840                         /* It was not sizeof(type) after all.  It is sizeof of an expression
7841                          * starting with a compound literal */
7842                         expression = parse_compound_literal(orig_type);
7843                         goto typeprop_expression;
7844                 }
7845         } else {
7846                 expression = parse_sub_expression(PREC_UNARY);
7847
7848 typeprop_expression:
7849                 tp_expression->typeprop.tp_expression = expression;
7850
7851                 orig_type = revert_automatic_type_conversion(expression);
7852                 expression->base.type = orig_type;
7853         }
7854
7855         tp_expression->typeprop.type   = orig_type;
7856         type_t const* const type       = skip_typeref(orig_type);
7857         char   const* const wrong_type =
7858                 is_type_incomplete(type)    ? "incomplete"          :
7859                 type->kind == TYPE_FUNCTION ? "function designator" :
7860                 type->kind == TYPE_BITFIELD ? "bitfield"            :
7861                 NULL;
7862         if (wrong_type != NULL) {
7863                 char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7864                 errorf(&tp_expression->base.source_position,
7865                                 "operand of %s expression must not be of %s type '%T'",
7866                                 what, wrong_type, orig_type);
7867         }
7868
7869 end_error:
7870         in_type_prop = old;
7871         return tp_expression;
7872 }
7873
7874 static expression_t *parse_sizeof(void)
7875 {
7876         return parse_typeprop(EXPR_SIZEOF);
7877 }
7878
7879 static expression_t *parse_alignof(void)
7880 {
7881         return parse_typeprop(EXPR_ALIGNOF);
7882 }
7883
7884 static expression_t *parse_select_expression(expression_t *compound)
7885 {
7886         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
7887         select->select.compound = compound;
7888
7889         assert(token.type == '.' || token.type == T_MINUSGREATER);
7890         bool is_pointer = (token.type == T_MINUSGREATER);
7891         next_token();
7892
7893         if (token.type != T_IDENTIFIER) {
7894                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
7895                 return select;
7896         }
7897         symbol_t *symbol = token.v.symbol;
7898         next_token();
7899
7900         type_t *const orig_type = compound->base.type;
7901         type_t *const type      = skip_typeref(orig_type);
7902
7903         type_t *type_left;
7904         bool    saw_error = false;
7905         if (is_type_pointer(type)) {
7906                 if (!is_pointer) {
7907                         errorf(HERE,
7908                                "request for member '%Y' in something not a struct or union, but '%T'",
7909                                symbol, orig_type);
7910                         saw_error = true;
7911                 }
7912                 type_left = skip_typeref(type->pointer.points_to);
7913         } else {
7914                 if (is_pointer && is_type_valid(type)) {
7915                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7916                         saw_error = true;
7917                 }
7918                 type_left = type;
7919         }
7920
7921         entity_t *entry;
7922         if (type_left->kind == TYPE_COMPOUND_STRUCT ||
7923             type_left->kind == TYPE_COMPOUND_UNION) {
7924                 compound_t *compound = type_left->compound.compound;
7925
7926                 if (!compound->complete) {
7927                         errorf(HERE, "request for member '%Y' of incomplete type '%T'",
7928                                symbol, type_left);
7929                         goto create_error_entry;
7930                 }
7931
7932                 entry = find_compound_entry(compound, symbol);
7933                 if (entry == NULL) {
7934                         errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
7935                         goto create_error_entry;
7936                 }
7937         } else {
7938                 if (is_type_valid(type_left) && !saw_error) {
7939                         errorf(HERE,
7940                                "request for member '%Y' in something not a struct or union, but '%T'",
7941                                symbol, type_left);
7942                 }
7943 create_error_entry:
7944                 return create_invalid_expression();
7945         }
7946
7947         assert(is_declaration(entry));
7948         select->select.compound_entry = entry;
7949
7950         type_t *entry_type = entry->declaration.type;
7951         type_t *res_type
7952                 = get_qualified_type(entry_type, type_left->base.qualifiers);
7953
7954         /* we always do the auto-type conversions; the & and sizeof parser contains
7955          * code to revert this! */
7956         select->base.type = automatic_type_conversion(res_type);
7957
7958         type_t *skipped = skip_typeref(res_type);
7959         if (skipped->kind == TYPE_BITFIELD) {
7960                 select->base.type = skipped->bitfield.base_type;
7961         }
7962
7963         return select;
7964 }
7965
7966 static void check_call_argument(const function_parameter_t *parameter,
7967                                 call_argument_t *argument, unsigned pos)
7968 {
7969         type_t         *expected_type      = parameter->type;
7970         type_t         *expected_type_skip = skip_typeref(expected_type);
7971         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
7972         expression_t   *arg_expr           = argument->expression;
7973         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
7974
7975         /* handle transparent union gnu extension */
7976         if (is_type_union(expected_type_skip)
7977                         && (expected_type_skip->base.modifiers
7978                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
7979                 compound_t *union_decl  = expected_type_skip->compound.compound;
7980                 type_t     *best_type   = NULL;
7981                 entity_t   *entry       = union_decl->members.entities;
7982                 for ( ; entry != NULL; entry = entry->base.next) {
7983                         assert(is_declaration(entry));
7984                         type_t *decl_type = entry->declaration.type;
7985                         error = semantic_assign(decl_type, arg_expr);
7986                         if (error == ASSIGN_ERROR_INCOMPATIBLE
7987                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
7988                                 continue;
7989
7990                         if (error == ASSIGN_SUCCESS) {
7991                                 best_type = decl_type;
7992                         } else if (best_type == NULL) {
7993                                 best_type = decl_type;
7994                         }
7995                 }
7996
7997                 if (best_type != NULL) {
7998                         expected_type = best_type;
7999                 }
8000         }
8001
8002         error                = semantic_assign(expected_type, arg_expr);
8003         argument->expression = create_implicit_cast(argument->expression,
8004                                                     expected_type);
8005
8006         if (error != ASSIGN_SUCCESS) {
8007                 /* report exact scope in error messages (like "in argument 3") */
8008                 char buf[64];
8009                 snprintf(buf, sizeof(buf), "call argument %u", pos);
8010                 report_assign_error(error, expected_type, arg_expr,     buf,
8011                                                         &arg_expr->base.source_position);
8012         } else if (warning.traditional || warning.conversion) {
8013                 type_t *const promoted_type = get_default_promoted_type(arg_type);
8014                 if (!types_compatible(expected_type_skip, promoted_type) &&
8015                     !types_compatible(expected_type_skip, type_void_ptr) &&
8016                     !types_compatible(type_void_ptr,      promoted_type)) {
8017                         /* Deliberately show the skipped types in this warning */
8018                         warningf(&arg_expr->base.source_position,
8019                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
8020                                 pos, expected_type_skip, promoted_type);
8021                 }
8022         }
8023 }
8024
8025 /**
8026  * Parse a call expression, ie. expression '( ... )'.
8027  *
8028  * @param expression  the function address
8029  */
8030 static expression_t *parse_call_expression(expression_t *expression)
8031 {
8032         expression_t      *result = allocate_expression_zero(EXPR_CALL);
8033         call_expression_t *call   = &result->call;
8034         call->function            = expression;
8035
8036         type_t *const orig_type = expression->base.type;
8037         type_t *const type      = skip_typeref(orig_type);
8038
8039         function_type_t *function_type = NULL;
8040         if (is_type_pointer(type)) {
8041                 type_t *const to_type = skip_typeref(type->pointer.points_to);
8042
8043                 if (is_type_function(to_type)) {
8044                         function_type   = &to_type->function;
8045                         call->base.type = function_type->return_type;
8046                 }
8047         }
8048
8049         if (function_type == NULL && is_type_valid(type)) {
8050                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
8051         }
8052
8053         /* parse arguments */
8054         eat('(');
8055         add_anchor_token(')');
8056         add_anchor_token(',');
8057
8058         if (token.type != ')') {
8059                 call_argument_t *last_argument = NULL;
8060
8061                 while (true) {
8062                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
8063
8064                         argument->expression = parse_assignment_expression();
8065                         if (last_argument == NULL) {
8066                                 call->arguments = argument;
8067                         } else {
8068                                 last_argument->next = argument;
8069                         }
8070                         last_argument = argument;
8071
8072                         if (token.type != ',')
8073                                 break;
8074                         next_token();
8075                 }
8076         }
8077         rem_anchor_token(',');
8078         rem_anchor_token(')');
8079         expect(')');
8080
8081         if (function_type == NULL)
8082                 return result;
8083
8084         function_parameter_t *parameter = function_type->parameters;
8085         call_argument_t      *argument  = call->arguments;
8086         if (!function_type->unspecified_parameters) {
8087                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
8088                                 parameter = parameter->next, argument = argument->next) {
8089                         check_call_argument(parameter, argument, ++pos);
8090                 }
8091
8092                 if (parameter != NULL) {
8093                         errorf(HERE, "too few arguments to function '%E'", expression);
8094                 } else if (argument != NULL && !function_type->variadic) {
8095                         errorf(HERE, "too many arguments to function '%E'", expression);
8096                 }
8097         }
8098
8099         /* do default promotion */
8100         for (; argument != NULL; argument = argument->next) {
8101                 type_t *type = argument->expression->base.type;
8102
8103                 type = get_default_promoted_type(type);
8104
8105                 argument->expression
8106                         = create_implicit_cast(argument->expression, type);
8107         }
8108
8109         check_format(&result->call);
8110
8111         if (warning.aggregate_return &&
8112             is_type_compound(skip_typeref(function_type->return_type))) {
8113                 warningf(&result->base.source_position,
8114                          "function call has aggregate value");
8115         }
8116
8117 end_error:
8118         return result;
8119 }
8120
8121 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
8122
8123 static bool same_compound_type(const type_t *type1, const type_t *type2)
8124 {
8125         return
8126                 is_type_compound(type1) &&
8127                 type1->kind == type2->kind &&
8128                 type1->compound.compound == type2->compound.compound;
8129 }
8130
8131 static expression_t const *get_reference_address(expression_t const *expr)
8132 {
8133         bool regular_take_address = true;
8134         for (;;) {
8135                 if (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8136                         expr = expr->unary.value;
8137                 } else {
8138                         regular_take_address = false;
8139                 }
8140
8141                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8142                         break;
8143
8144                 expr = expr->unary.value;
8145         }
8146
8147         if (expr->kind != EXPR_REFERENCE)
8148                 return NULL;
8149
8150         /* special case for functions which are automatically converted to a
8151          * pointer to function without an extra TAKE_ADDRESS operation */
8152         if (!regular_take_address &&
8153                         expr->reference.entity->kind != ENTITY_FUNCTION) {
8154                 return NULL;
8155         }
8156
8157         return expr;
8158 }
8159
8160 static void warn_reference_address_as_bool(expression_t const* expr)
8161 {
8162         if (!warning.address)
8163                 return;
8164
8165         expr = get_reference_address(expr);
8166         if (expr != NULL) {
8167                 warningf(&expr->base.source_position,
8168                          "the address of '%Y' will always evaluate as 'true'",
8169                          expr->reference.entity->base.symbol);
8170         }
8171 }
8172
8173 static void semantic_condition(expression_t const *const expr,
8174                                char const *const context)
8175 {
8176         type_t *const type = skip_typeref(expr->base.type);
8177         if (is_type_scalar(type)) {
8178                 warn_reference_address_as_bool(expr);
8179         } else if (is_type_valid(type)) {
8180                 errorf(&expr->base.source_position,
8181                                 "%s must have scalar type", context);
8182         }
8183 }
8184
8185 /**
8186  * Parse a conditional expression, ie. 'expression ? ... : ...'.
8187  *
8188  * @param expression  the conditional expression
8189  */
8190 static expression_t *parse_conditional_expression(expression_t *expression)
8191 {
8192         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
8193
8194         conditional_expression_t *conditional = &result->conditional;
8195         conditional->condition                = expression;
8196
8197         eat('?');
8198         add_anchor_token(':');
8199
8200         /* §6.5.15:2  The first operand shall have scalar type. */
8201         semantic_condition(expression, "condition of conditional operator");
8202
8203         expression_t *true_expression = expression;
8204         bool          gnu_cond = false;
8205         if (GNU_MODE && token.type == ':') {
8206                 gnu_cond = true;
8207         } else {
8208                 true_expression = parse_expression();
8209         }
8210         rem_anchor_token(':');
8211         expect(':');
8212         expression_t *false_expression =
8213                 parse_sub_expression(c_mode & _CXX ? PREC_ASSIGNMENT : PREC_CONDITIONAL);
8214
8215         type_t *const orig_true_type  = true_expression->base.type;
8216         type_t *const orig_false_type = false_expression->base.type;
8217         type_t *const true_type       = skip_typeref(orig_true_type);
8218         type_t *const false_type      = skip_typeref(orig_false_type);
8219
8220         /* 6.5.15.3 */
8221         type_t *result_type;
8222         if (is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8223                         is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
8224                 /* ISO/IEC 14882:1998(E) §5.16:2 */
8225                 if (true_expression->kind == EXPR_UNARY_THROW) {
8226                         result_type = false_type;
8227                 } else if (false_expression->kind == EXPR_UNARY_THROW) {
8228                         result_type = true_type;
8229                 } else {
8230                         if (warning.other && (
8231                                                 !is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8232                                                 !is_type_atomic(false_type, ATOMIC_TYPE_VOID)
8233                                         )) {
8234                                 warningf(&conditional->base.source_position,
8235                                                 "ISO C forbids conditional expression with only one void side");
8236                         }
8237                         result_type = type_void;
8238                 }
8239         } else if (is_type_arithmetic(true_type)
8240                    && is_type_arithmetic(false_type)) {
8241                 result_type = semantic_arithmetic(true_type, false_type);
8242
8243                 true_expression  = create_implicit_cast(true_expression, result_type);
8244                 false_expression = create_implicit_cast(false_expression, result_type);
8245
8246                 conditional->true_expression  = true_expression;
8247                 conditional->false_expression = false_expression;
8248                 conditional->base.type        = result_type;
8249         } else if (same_compound_type(true_type, false_type)) {
8250                 /* just take 1 of the 2 types */
8251                 result_type = true_type;
8252         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
8253                 type_t *pointer_type;
8254                 type_t *other_type;
8255                 expression_t *other_expression;
8256                 if (is_type_pointer(true_type) &&
8257                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
8258                         pointer_type     = true_type;
8259                         other_type       = false_type;
8260                         other_expression = false_expression;
8261                 } else {
8262                         pointer_type     = false_type;
8263                         other_type       = true_type;
8264                         other_expression = true_expression;
8265                 }
8266
8267                 if (is_null_pointer_constant(other_expression)) {
8268                         result_type = pointer_type;
8269                 } else if (is_type_pointer(other_type)) {
8270                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
8271                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
8272
8273                         type_t *to;
8274                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
8275                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
8276                                 to = type_void;
8277                         } else if (types_compatible(get_unqualified_type(to1),
8278                                                     get_unqualified_type(to2))) {
8279                                 to = to1;
8280                         } else {
8281                                 if (warning.other) {
8282                                         warningf(&conditional->base.source_position,
8283                                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
8284                                                         true_type, false_type);
8285                                 }
8286                                 to = type_void;
8287                         }
8288
8289                         type_t *const type =
8290                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
8291                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
8292                 } else if (is_type_integer(other_type)) {
8293                         if (warning.other) {
8294                                 warningf(&conditional->base.source_position,
8295                                                 "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
8296                         }
8297                         result_type = pointer_type;
8298                 } else {
8299                         if (is_type_valid(other_type)) {
8300                                 type_error_incompatible("while parsing conditional",
8301                                                 &expression->base.source_position, true_type, false_type);
8302                         }
8303                         result_type = type_error_type;
8304                 }
8305         } else {
8306                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
8307                         type_error_incompatible("while parsing conditional",
8308                                                 &conditional->base.source_position, true_type,
8309                                                 false_type);
8310                 }
8311                 result_type = type_error_type;
8312         }
8313
8314         conditional->true_expression
8315                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
8316         conditional->false_expression
8317                 = create_implicit_cast(false_expression, result_type);
8318         conditional->base.type = result_type;
8319         return result;
8320 end_error:
8321         return create_invalid_expression();
8322 }
8323
8324 /**
8325  * Parse an extension expression.
8326  */
8327 static expression_t *parse_extension(void)
8328 {
8329         eat(T___extension__);
8330
8331         bool old_gcc_extension   = in_gcc_extension;
8332         in_gcc_extension         = true;
8333         expression_t *expression = parse_sub_expression(PREC_UNARY);
8334         in_gcc_extension         = old_gcc_extension;
8335         return expression;
8336 }
8337
8338 /**
8339  * Parse a __builtin_classify_type() expression.
8340  */
8341 static expression_t *parse_builtin_classify_type(void)
8342 {
8343         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
8344         result->base.type    = type_int;
8345
8346         eat(T___builtin_classify_type);
8347
8348         expect('(');
8349         add_anchor_token(')');
8350         expression_t *expression = parse_expression();
8351         rem_anchor_token(')');
8352         expect(')');
8353         result->classify_type.type_expression = expression;
8354
8355         return result;
8356 end_error:
8357         return create_invalid_expression();
8358 }
8359
8360 /**
8361  * Parse a delete expression
8362  * ISO/IEC 14882:1998(E) §5.3.5
8363  */
8364 static expression_t *parse_delete(void)
8365 {
8366         expression_t *const result = allocate_expression_zero(EXPR_UNARY_DELETE);
8367         result->base.type          = type_void;
8368
8369         eat(T_delete);
8370
8371         if (token.type == '[') {
8372                 next_token();
8373                 result->kind = EXPR_UNARY_DELETE_ARRAY;
8374                 expect(']');
8375 end_error:;
8376         }
8377
8378         expression_t *const value = parse_sub_expression(PREC_CAST);
8379         result->unary.value = value;
8380
8381         type_t *const type = skip_typeref(value->base.type);
8382         if (!is_type_pointer(type)) {
8383                 errorf(&value->base.source_position,
8384                                 "operand of delete must have pointer type");
8385         } else if (warning.other &&
8386                         is_type_atomic(skip_typeref(type->pointer.points_to), ATOMIC_TYPE_VOID)) {
8387                 warningf(&value->base.source_position,
8388                                 "deleting 'void*' is undefined");
8389         }
8390
8391         return result;
8392 }
8393
8394 /**
8395  * Parse a throw expression
8396  * ISO/IEC 14882:1998(E) §15:1
8397  */
8398 static expression_t *parse_throw(void)
8399 {
8400         expression_t *const result = allocate_expression_zero(EXPR_UNARY_THROW);
8401         result->base.type          = type_void;
8402
8403         eat(T_throw);
8404
8405         expression_t *value = NULL;
8406         switch (token.type) {
8407                 EXPRESSION_START {
8408                         value = parse_assignment_expression();
8409                         /* ISO/IEC 14882:1998(E) §15.1:3 */
8410                         type_t *const orig_type = value->base.type;
8411                         type_t *const type      = skip_typeref(orig_type);
8412                         if (is_type_incomplete(type)) {
8413                                 errorf(&value->base.source_position,
8414                                                 "cannot throw object of incomplete type '%T'", orig_type);
8415                         } else if (is_type_pointer(type)) {
8416                                 type_t *const points_to = skip_typeref(type->pointer.points_to);
8417                                 if (is_type_incomplete(points_to) &&
8418                                                 !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8419                                         errorf(&value->base.source_position,
8420                                                         "cannot throw pointer to incomplete type '%T'", orig_type);
8421                                 }
8422                         }
8423                 }
8424
8425                 default:
8426                         break;
8427         }
8428         result->unary.value = value;
8429
8430         return result;
8431 }
8432
8433 static bool check_pointer_arithmetic(const source_position_t *source_position,
8434                                      type_t *pointer_type,
8435                                      type_t *orig_pointer_type)
8436 {
8437         type_t *points_to = pointer_type->pointer.points_to;
8438         points_to = skip_typeref(points_to);
8439
8440         if (is_type_incomplete(points_to)) {
8441                 if (!GNU_MODE || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8442                         errorf(source_position,
8443                                "arithmetic with pointer to incomplete type '%T' not allowed",
8444                                orig_pointer_type);
8445                         return false;
8446                 } else if (warning.pointer_arith) {
8447                         warningf(source_position,
8448                                  "pointer of type '%T' used in arithmetic",
8449                                  orig_pointer_type);
8450                 }
8451         } else if (is_type_function(points_to)) {
8452                 if (!GNU_MODE) {
8453                         errorf(source_position,
8454                                "arithmetic with pointer to function type '%T' not allowed",
8455                                orig_pointer_type);
8456                         return false;
8457                 } else if (warning.pointer_arith) {
8458                         warningf(source_position,
8459                                  "pointer to a function '%T' used in arithmetic",
8460                                  orig_pointer_type);
8461                 }
8462         }
8463         return true;
8464 }
8465
8466 static bool is_lvalue(const expression_t *expression)
8467 {
8468         /* TODO: doesn't seem to be consistent with §6.3.2.1 (1) */
8469         switch (expression->kind) {
8470         case EXPR_REFERENCE:
8471         case EXPR_ARRAY_ACCESS:
8472         case EXPR_SELECT:
8473         case EXPR_UNARY_DEREFERENCE:
8474                 return true;
8475
8476         default: {
8477           type_t *type = skip_typeref(expression->base.type);
8478           return
8479                 /* ISO/IEC 14882:1998(E) §3.10:3 */
8480                 is_type_reference(type) ||
8481                 /* Claim it is an lvalue, if the type is invalid.  There was a parse
8482                  * error before, which maybe prevented properly recognizing it as
8483                  * lvalue. */
8484                 !is_type_valid(type);
8485         }
8486         }
8487 }
8488
8489 static void semantic_incdec(unary_expression_t *expression)
8490 {
8491         type_t *const orig_type = expression->value->base.type;
8492         type_t *const type      = skip_typeref(orig_type);
8493         if (is_type_pointer(type)) {
8494                 if (!check_pointer_arithmetic(&expression->base.source_position,
8495                                               type, orig_type)) {
8496                         return;
8497                 }
8498         } else if (!is_type_real(type) && is_type_valid(type)) {
8499                 /* TODO: improve error message */
8500                 errorf(&expression->base.source_position,
8501                        "operation needs an arithmetic or pointer type");
8502                 return;
8503         }
8504         if (!is_lvalue(expression->value)) {
8505                 /* TODO: improve error message */
8506                 errorf(&expression->base.source_position, "lvalue required as operand");
8507         }
8508         expression->base.type = orig_type;
8509 }
8510
8511 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
8512 {
8513         type_t *const orig_type = expression->value->base.type;
8514         type_t *const type      = skip_typeref(orig_type);
8515         if (!is_type_arithmetic(type)) {
8516                 if (is_type_valid(type)) {
8517                         /* TODO: improve error message */
8518                         errorf(&expression->base.source_position,
8519                                 "operation needs an arithmetic type");
8520                 }
8521                 return;
8522         }
8523
8524         expression->base.type = orig_type;
8525 }
8526
8527 static void semantic_unexpr_plus(unary_expression_t *expression)
8528 {
8529         semantic_unexpr_arithmetic(expression);
8530         if (warning.traditional)
8531                 warningf(&expression->base.source_position,
8532                         "traditional C rejects the unary plus operator");
8533 }
8534
8535 static void semantic_not(unary_expression_t *expression)
8536 {
8537         /* §6.5.3.3:1  The operand [...] of the ! operator, scalar type. */
8538         semantic_condition(expression->value, "operand of !");
8539         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8540 }
8541
8542 static void semantic_unexpr_integer(unary_expression_t *expression)
8543 {
8544         type_t *const orig_type = expression->value->base.type;
8545         type_t *const type      = skip_typeref(orig_type);
8546         if (!is_type_integer(type)) {
8547                 if (is_type_valid(type)) {
8548                         errorf(&expression->base.source_position,
8549                                "operand of ~ must be of integer type");
8550                 }
8551                 return;
8552         }
8553
8554         expression->base.type = orig_type;
8555 }
8556
8557 static void semantic_dereference(unary_expression_t *expression)
8558 {
8559         type_t *const orig_type = expression->value->base.type;
8560         type_t *const type      = skip_typeref(orig_type);
8561         if (!is_type_pointer(type)) {
8562                 if (is_type_valid(type)) {
8563                         errorf(&expression->base.source_position,
8564                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
8565                 }
8566                 return;
8567         }
8568
8569         type_t *result_type   = type->pointer.points_to;
8570         result_type           = automatic_type_conversion(result_type);
8571         expression->base.type = result_type;
8572 }
8573
8574 /**
8575  * Record that an address is taken (expression represents an lvalue).
8576  *
8577  * @param expression       the expression
8578  * @param may_be_register  if true, the expression might be an register
8579  */
8580 static void set_address_taken(expression_t *expression, bool may_be_register)
8581 {
8582         if (expression->kind != EXPR_REFERENCE)
8583                 return;
8584
8585         entity_t *const entity = expression->reference.entity;
8586
8587         if (entity->kind != ENTITY_VARIABLE && entity->kind != ENTITY_PARAMETER)
8588                 return;
8589
8590         if (entity->declaration.storage_class == STORAGE_CLASS_REGISTER
8591                         && !may_be_register) {
8592                 errorf(&expression->base.source_position,
8593                                 "address of register %s '%Y' requested",
8594                                 get_entity_kind_name(entity->kind),     entity->base.symbol);
8595         }
8596
8597         if (entity->kind == ENTITY_VARIABLE) {
8598                 entity->variable.address_taken = true;
8599         } else {
8600                 assert(entity->kind == ENTITY_PARAMETER);
8601                 entity->parameter.address_taken = true;
8602         }
8603 }
8604
8605 /**
8606  * Check the semantic of the address taken expression.
8607  */
8608 static void semantic_take_addr(unary_expression_t *expression)
8609 {
8610         expression_t *value = expression->value;
8611         value->base.type    = revert_automatic_type_conversion(value);
8612
8613         type_t *orig_type = value->base.type;
8614         type_t *type      = skip_typeref(orig_type);
8615         if (!is_type_valid(type))
8616                 return;
8617
8618         /* §6.5.3.2 */
8619         if (!is_lvalue(value)) {
8620                 errorf(&expression->base.source_position, "'&' requires an lvalue");
8621         }
8622         if (type->kind == TYPE_BITFIELD) {
8623                 errorf(&expression->base.source_position,
8624                        "'&' not allowed on object with bitfield type '%T'",
8625                        type);
8626         }
8627
8628         set_address_taken(value, false);
8629
8630         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
8631 }
8632
8633 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc) \
8634 static expression_t *parse_##unexpression_type(void)                         \
8635 {                                                                            \
8636         expression_t *unary_expression                                           \
8637                 = allocate_expression_zero(unexpression_type);                       \
8638         eat(token_type);                                                         \
8639         unary_expression->unary.value = parse_sub_expression(PREC_UNARY);        \
8640                                                                                  \
8641         sfunc(&unary_expression->unary);                                         \
8642                                                                                  \
8643         return unary_expression;                                                 \
8644 }
8645
8646 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
8647                                semantic_unexpr_arithmetic)
8648 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
8649                                semantic_unexpr_plus)
8650 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
8651                                semantic_not)
8652 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
8653                                semantic_dereference)
8654 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
8655                                semantic_take_addr)
8656 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
8657                                semantic_unexpr_integer)
8658 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
8659                                semantic_incdec)
8660 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
8661                                semantic_incdec)
8662
8663 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
8664                                                sfunc)                         \
8665 static expression_t *parse_##unexpression_type(expression_t *left)            \
8666 {                                                                             \
8667         expression_t *unary_expression                                            \
8668                 = allocate_expression_zero(unexpression_type);                        \
8669         eat(token_type);                                                          \
8670         unary_expression->unary.value = left;                                     \
8671                                                                                   \
8672         sfunc(&unary_expression->unary);                                          \
8673                                                                               \
8674         return unary_expression;                                                  \
8675 }
8676
8677 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
8678                                        EXPR_UNARY_POSTFIX_INCREMENT,
8679                                        semantic_incdec)
8680 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
8681                                        EXPR_UNARY_POSTFIX_DECREMENT,
8682                                        semantic_incdec)
8683
8684 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
8685 {
8686         /* TODO: handle complex + imaginary types */
8687
8688         type_left  = get_unqualified_type(type_left);
8689         type_right = get_unqualified_type(type_right);
8690
8691         /* § 6.3.1.8 Usual arithmetic conversions */
8692         if (type_left == type_long_double || type_right == type_long_double) {
8693                 return type_long_double;
8694         } else if (type_left == type_double || type_right == type_double) {
8695                 return type_double;
8696         } else if (type_left == type_float || type_right == type_float) {
8697                 return type_float;
8698         }
8699
8700         type_left  = promote_integer(type_left);
8701         type_right = promote_integer(type_right);
8702
8703         if (type_left == type_right)
8704                 return type_left;
8705
8706         bool const signed_left  = is_type_signed(type_left);
8707         bool const signed_right = is_type_signed(type_right);
8708         int const  rank_left    = get_rank(type_left);
8709         int const  rank_right   = get_rank(type_right);
8710
8711         if (signed_left == signed_right)
8712                 return rank_left >= rank_right ? type_left : type_right;
8713
8714         int     s_rank;
8715         int     u_rank;
8716         type_t *s_type;
8717         type_t *u_type;
8718         if (signed_left) {
8719                 s_rank = rank_left;
8720                 s_type = type_left;
8721                 u_rank = rank_right;
8722                 u_type = type_right;
8723         } else {
8724                 s_rank = rank_right;
8725                 s_type = type_right;
8726                 u_rank = rank_left;
8727                 u_type = type_left;
8728         }
8729
8730         if (u_rank >= s_rank)
8731                 return u_type;
8732
8733         /* casting rank to atomic_type_kind is a bit hacky, but makes things
8734          * easier here... */
8735         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
8736                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
8737                 return s_type;
8738
8739         switch (s_rank) {
8740                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
8741                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
8742                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
8743
8744                 default: panic("invalid atomic type");
8745         }
8746 }
8747
8748 /**
8749  * Check the semantic restrictions for a binary expression.
8750  */
8751 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
8752 {
8753         expression_t *const left            = expression->left;
8754         expression_t *const right           = expression->right;
8755         type_t       *const orig_type_left  = left->base.type;
8756         type_t       *const orig_type_right = right->base.type;
8757         type_t       *const type_left       = skip_typeref(orig_type_left);
8758         type_t       *const type_right      = skip_typeref(orig_type_right);
8759
8760         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8761                 /* TODO: improve error message */
8762                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8763                         errorf(&expression->base.source_position,
8764                                "operation needs arithmetic types");
8765                 }
8766                 return;
8767         }
8768
8769         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8770         expression->left      = create_implicit_cast(left, arithmetic_type);
8771         expression->right     = create_implicit_cast(right, arithmetic_type);
8772         expression->base.type = arithmetic_type;
8773 }
8774
8775 static void warn_div_by_zero(binary_expression_t const *const expression)
8776 {
8777         if (!warning.div_by_zero ||
8778             !is_type_integer(expression->base.type))
8779                 return;
8780
8781         expression_t const *const right = expression->right;
8782         /* The type of the right operand can be different for /= */
8783         if (is_type_integer(right->base.type) &&
8784             is_constant_expression(right)     &&
8785             fold_constant(right) == 0) {
8786                 warningf(&expression->base.source_position, "division by zero");
8787         }
8788 }
8789
8790 /**
8791  * Check the semantic restrictions for a div/mod expression.
8792  */
8793 static void semantic_divmod_arithmetic(binary_expression_t *expression) {
8794         semantic_binexpr_arithmetic(expression);
8795         warn_div_by_zero(expression);
8796 }
8797
8798 static void semantic_shift_op(binary_expression_t *expression)
8799 {
8800         expression_t *const left            = expression->left;
8801         expression_t *const right           = expression->right;
8802         type_t       *const orig_type_left  = left->base.type;
8803         type_t       *const orig_type_right = right->base.type;
8804         type_t       *      type_left       = skip_typeref(orig_type_left);
8805         type_t       *      type_right      = skip_typeref(orig_type_right);
8806
8807         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8808                 /* TODO: improve error message */
8809                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8810                         errorf(&expression->base.source_position,
8811                                "operands of shift operation must have integer types");
8812                 }
8813                 return;
8814         }
8815
8816         type_left  = promote_integer(type_left);
8817         type_right = promote_integer(type_right);
8818
8819         expression->left      = create_implicit_cast(left, type_left);
8820         expression->right     = create_implicit_cast(right, type_right);
8821         expression->base.type = type_left;
8822 }
8823
8824 static void semantic_add(binary_expression_t *expression)
8825 {
8826         expression_t *const left            = expression->left;
8827         expression_t *const right           = expression->right;
8828         type_t       *const orig_type_left  = left->base.type;
8829         type_t       *const orig_type_right = right->base.type;
8830         type_t       *const type_left       = skip_typeref(orig_type_left);
8831         type_t       *const type_right      = skip_typeref(orig_type_right);
8832
8833         /* § 6.5.6 */
8834         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8835                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8836                 expression->left  = create_implicit_cast(left, arithmetic_type);
8837                 expression->right = create_implicit_cast(right, arithmetic_type);
8838                 expression->base.type = arithmetic_type;
8839                 return;
8840         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8841                 check_pointer_arithmetic(&expression->base.source_position,
8842                                          type_left, orig_type_left);
8843                 expression->base.type = type_left;
8844         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
8845                 check_pointer_arithmetic(&expression->base.source_position,
8846                                          type_right, orig_type_right);
8847                 expression->base.type = type_right;
8848         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8849                 errorf(&expression->base.source_position,
8850                        "invalid operands to binary + ('%T', '%T')",
8851                        orig_type_left, orig_type_right);
8852         }
8853 }
8854
8855 static void semantic_sub(binary_expression_t *expression)
8856 {
8857         expression_t            *const left            = expression->left;
8858         expression_t            *const right           = expression->right;
8859         type_t                  *const orig_type_left  = left->base.type;
8860         type_t                  *const orig_type_right = right->base.type;
8861         type_t                  *const type_left       = skip_typeref(orig_type_left);
8862         type_t                  *const type_right      = skip_typeref(orig_type_right);
8863         source_position_t const *const pos             = &expression->base.source_position;
8864
8865         /* § 5.6.5 */
8866         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8867                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8868                 expression->left        = create_implicit_cast(left, arithmetic_type);
8869                 expression->right       = create_implicit_cast(right, arithmetic_type);
8870                 expression->base.type =  arithmetic_type;
8871                 return;
8872         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8873                 check_pointer_arithmetic(&expression->base.source_position,
8874                                          type_left, orig_type_left);
8875                 expression->base.type = type_left;
8876         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8877                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
8878                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
8879                 if (!types_compatible(unqual_left, unqual_right)) {
8880                         errorf(pos,
8881                                "subtracting pointers to incompatible types '%T' and '%T'",
8882                                orig_type_left, orig_type_right);
8883                 } else if (!is_type_object(unqual_left)) {
8884                         if (!is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
8885                                 errorf(pos, "subtracting pointers to non-object types '%T'",
8886                                        orig_type_left);
8887                         } else if (warning.other) {
8888                                 warningf(pos, "subtracting pointers to void");
8889                         }
8890                 }
8891                 expression->base.type = type_ptrdiff_t;
8892         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8893                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
8894                        orig_type_left, orig_type_right);
8895         }
8896 }
8897
8898 static void warn_string_literal_address(expression_t const* expr)
8899 {
8900         while (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8901                 expr = expr->unary.value;
8902                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8903                         return;
8904                 expr = expr->unary.value;
8905         }
8906
8907         if (expr->kind == EXPR_STRING_LITERAL ||
8908             expr->kind == EXPR_WIDE_STRING_LITERAL) {
8909                 warningf(&expr->base.source_position,
8910                         "comparison with string literal results in unspecified behaviour");
8911         }
8912 }
8913
8914 /**
8915  * Check the semantics of comparison expressions.
8916  *
8917  * @param expression   The expression to check.
8918  */
8919 static void semantic_comparison(binary_expression_t *expression)
8920 {
8921         expression_t *left  = expression->left;
8922         expression_t *right = expression->right;
8923
8924         if (warning.address) {
8925                 warn_string_literal_address(left);
8926                 warn_string_literal_address(right);
8927
8928                 expression_t const* const func_left = get_reference_address(left);
8929                 if (func_left != NULL && is_null_pointer_constant(right)) {
8930                         warningf(&expression->base.source_position,
8931                                  "the address of '%Y' will never be NULL",
8932                                  func_left->reference.entity->base.symbol);
8933                 }
8934
8935                 expression_t const* const func_right = get_reference_address(right);
8936                 if (func_right != NULL && is_null_pointer_constant(right)) {
8937                         warningf(&expression->base.source_position,
8938                                  "the address of '%Y' will never be NULL",
8939                                  func_right->reference.entity->base.symbol);
8940                 }
8941         }
8942
8943         type_t *orig_type_left  = left->base.type;
8944         type_t *orig_type_right = right->base.type;
8945         type_t *type_left       = skip_typeref(orig_type_left);
8946         type_t *type_right      = skip_typeref(orig_type_right);
8947
8948         /* TODO non-arithmetic types */
8949         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8950                 /* test for signed vs unsigned compares */
8951                 if (warning.sign_compare &&
8952                     (expression->base.kind != EXPR_BINARY_EQUAL &&
8953                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
8954                     (is_type_signed(type_left) != is_type_signed(type_right))) {
8955
8956                         /* check if 1 of the operands is a constant, in this case we just
8957                          * check wether we can safely represent the resulting constant in
8958                          * the type of the other operand. */
8959                         expression_t *const_expr = NULL;
8960                         expression_t *other_expr = NULL;
8961
8962                         if (is_constant_expression(left)) {
8963                                 const_expr = left;
8964                                 other_expr = right;
8965                         } else if (is_constant_expression(right)) {
8966                                 const_expr = right;
8967                                 other_expr = left;
8968                         }
8969
8970                         if (const_expr != NULL) {
8971                                 type_t *other_type = skip_typeref(other_expr->base.type);
8972                                 long    val        = fold_constant(const_expr);
8973                                 /* TODO: check if val can be represented by other_type */
8974                                 (void) other_type;
8975                                 (void) val;
8976                         }
8977                         warningf(&expression->base.source_position,
8978                                  "comparison between signed and unsigned");
8979                 }
8980                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8981                 expression->left        = create_implicit_cast(left, arithmetic_type);
8982                 expression->right       = create_implicit_cast(right, arithmetic_type);
8983                 expression->base.type   = arithmetic_type;
8984                 if (warning.float_equal &&
8985                     (expression->base.kind == EXPR_BINARY_EQUAL ||
8986                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
8987                     is_type_float(arithmetic_type)) {
8988                         warningf(&expression->base.source_position,
8989                                  "comparing floating point with == or != is unsafe");
8990                 }
8991         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8992                 /* TODO check compatibility */
8993         } else if (is_type_pointer(type_left)) {
8994                 expression->right = create_implicit_cast(right, type_left);
8995         } else if (is_type_pointer(type_right)) {
8996                 expression->left = create_implicit_cast(left, type_right);
8997         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8998                 type_error_incompatible("invalid operands in comparison",
8999                                         &expression->base.source_position,
9000                                         type_left, type_right);
9001         }
9002         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9003 }
9004
9005 /**
9006  * Checks if a compound type has constant fields.
9007  */
9008 static bool has_const_fields(const compound_type_t *type)
9009 {
9010         compound_t *compound = type->compound;
9011         entity_t   *entry    = compound->members.entities;
9012
9013         for (; entry != NULL; entry = entry->base.next) {
9014                 if (!is_declaration(entry))
9015                         continue;
9016
9017                 const type_t *decl_type = skip_typeref(entry->declaration.type);
9018                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
9019                         return true;
9020         }
9021
9022         return false;
9023 }
9024
9025 static bool is_valid_assignment_lhs(expression_t const* const left)
9026 {
9027         type_t *const orig_type_left = revert_automatic_type_conversion(left);
9028         type_t *const type_left      = skip_typeref(orig_type_left);
9029
9030         if (!is_lvalue(left)) {
9031                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
9032                        left);
9033                 return false;
9034         }
9035
9036         if (left->kind == EXPR_REFERENCE
9037                         && left->reference.entity->kind == ENTITY_FUNCTION) {
9038                 errorf(HERE, "cannot assign to function '%E'", left);
9039                 return false;
9040         }
9041
9042         if (is_type_array(type_left)) {
9043                 errorf(HERE, "cannot assign to array '%E'", left);
9044                 return false;
9045         }
9046         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
9047                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
9048                        orig_type_left);
9049                 return false;
9050         }
9051         if (is_type_incomplete(type_left)) {
9052                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
9053                        left, orig_type_left);
9054                 return false;
9055         }
9056         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
9057                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
9058                        left, orig_type_left);
9059                 return false;
9060         }
9061
9062         return true;
9063 }
9064
9065 static void semantic_arithmetic_assign(binary_expression_t *expression)
9066 {
9067         expression_t *left            = expression->left;
9068         expression_t *right           = expression->right;
9069         type_t       *orig_type_left  = left->base.type;
9070         type_t       *orig_type_right = right->base.type;
9071
9072         if (!is_valid_assignment_lhs(left))
9073                 return;
9074
9075         type_t *type_left  = skip_typeref(orig_type_left);
9076         type_t *type_right = skip_typeref(orig_type_right);
9077
9078         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
9079                 /* TODO: improve error message */
9080                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
9081                         errorf(&expression->base.source_position,
9082                                "operation needs arithmetic types");
9083                 }
9084                 return;
9085         }
9086
9087         /* combined instructions are tricky. We can't create an implicit cast on
9088          * the left side, because we need the uncasted form for the store.
9089          * The ast2firm pass has to know that left_type must be right_type
9090          * for the arithmetic operation and create a cast by itself */
9091         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
9092         expression->right       = create_implicit_cast(right, arithmetic_type);
9093         expression->base.type   = type_left;
9094 }
9095
9096 static void semantic_divmod_assign(binary_expression_t *expression)
9097 {
9098         semantic_arithmetic_assign(expression);
9099         warn_div_by_zero(expression);
9100 }
9101
9102 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
9103 {
9104         expression_t *const left            = expression->left;
9105         expression_t *const right           = expression->right;
9106         type_t       *const orig_type_left  = left->base.type;
9107         type_t       *const orig_type_right = right->base.type;
9108         type_t       *const type_left       = skip_typeref(orig_type_left);
9109         type_t       *const type_right      = skip_typeref(orig_type_right);
9110
9111         if (!is_valid_assignment_lhs(left))
9112                 return;
9113
9114         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
9115                 /* combined instructions are tricky. We can't create an implicit cast on
9116                  * the left side, because we need the uncasted form for the store.
9117                  * The ast2firm pass has to know that left_type must be right_type
9118                  * for the arithmetic operation and create a cast by itself */
9119                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
9120                 expression->right     = create_implicit_cast(right, arithmetic_type);
9121                 expression->base.type = type_left;
9122         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
9123                 check_pointer_arithmetic(&expression->base.source_position,
9124                                          type_left, orig_type_left);
9125                 expression->base.type = type_left;
9126         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9127                 errorf(&expression->base.source_position,
9128                        "incompatible types '%T' and '%T' in assignment",
9129                        orig_type_left, orig_type_right);
9130         }
9131 }
9132
9133 /**
9134  * Check the semantic restrictions of a logical expression.
9135  */
9136 static void semantic_logical_op(binary_expression_t *expression)
9137 {
9138         /* §6.5.13:2  Each of the operands shall have scalar type.
9139          * §6.5.14:2  Each of the operands shall have scalar type. */
9140         semantic_condition(expression->left,   "left operand of logical operator");
9141         semantic_condition(expression->right, "right operand of logical operator");
9142         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9143 }
9144
9145 /**
9146  * Check the semantic restrictions of a binary assign expression.
9147  */
9148 static void semantic_binexpr_assign(binary_expression_t *expression)
9149 {
9150         expression_t *left           = expression->left;
9151         type_t       *orig_type_left = left->base.type;
9152
9153         if (!is_valid_assignment_lhs(left))
9154                 return;
9155
9156         assign_error_t error = semantic_assign(orig_type_left, expression->right);
9157         report_assign_error(error, orig_type_left, expression->right,
9158                         "assignment", &left->base.source_position);
9159         expression->right = create_implicit_cast(expression->right, orig_type_left);
9160         expression->base.type = orig_type_left;
9161 }
9162
9163 /**
9164  * Determine if the outermost operation (or parts thereof) of the given
9165  * expression has no effect in order to generate a warning about this fact.
9166  * Therefore in some cases this only examines some of the operands of the
9167  * expression (see comments in the function and examples below).
9168  * Examples:
9169  *   f() + 23;    // warning, because + has no effect
9170  *   x || f();    // no warning, because x controls execution of f()
9171  *   x ? y : f(); // warning, because y has no effect
9172  *   (void)x;     // no warning to be able to suppress the warning
9173  * This function can NOT be used for an "expression has definitely no effect"-
9174  * analysis. */
9175 static bool expression_has_effect(const expression_t *const expr)
9176 {
9177         switch (expr->kind) {
9178                 case EXPR_UNKNOWN:                   break;
9179                 case EXPR_INVALID:                   return true; /* do NOT warn */
9180                 case EXPR_REFERENCE:                 return false;
9181                 case EXPR_REFERENCE_ENUM_VALUE:      return false;
9182                 /* suppress the warning for microsoft __noop operations */
9183                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
9184                 case EXPR_CHARACTER_CONSTANT:        return false;
9185                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
9186                 case EXPR_STRING_LITERAL:            return false;
9187                 case EXPR_WIDE_STRING_LITERAL:       return false;
9188                 case EXPR_LABEL_ADDRESS:             return false;
9189
9190                 case EXPR_CALL: {
9191                         const call_expression_t *const call = &expr->call;
9192                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
9193                                 return true;
9194
9195                         switch (call->function->builtin_symbol.symbol->ID) {
9196                                 case T___builtin_va_end: return true;
9197                                 default:                 return false;
9198                         }
9199                 }
9200
9201                 /* Generate the warning if either the left or right hand side of a
9202                  * conditional expression has no effect */
9203                 case EXPR_CONDITIONAL: {
9204                         const conditional_expression_t *const cond = &expr->conditional;
9205                         return
9206                                 expression_has_effect(cond->true_expression) &&
9207                                 expression_has_effect(cond->false_expression);
9208                 }
9209
9210                 case EXPR_SELECT:                    return false;
9211                 case EXPR_ARRAY_ACCESS:              return false;
9212                 case EXPR_SIZEOF:                    return false;
9213                 case EXPR_CLASSIFY_TYPE:             return false;
9214                 case EXPR_ALIGNOF:                   return false;
9215
9216                 case EXPR_FUNCNAME:                  return false;
9217                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
9218                 case EXPR_BUILTIN_CONSTANT_P:        return false;
9219                 case EXPR_BUILTIN_PREFETCH:          return true;
9220                 case EXPR_OFFSETOF:                  return false;
9221                 case EXPR_VA_START:                  return true;
9222                 case EXPR_VA_ARG:                    return true;
9223                 case EXPR_STATEMENT:                 return true; // TODO
9224                 case EXPR_COMPOUND_LITERAL:          return false;
9225
9226                 case EXPR_UNARY_NEGATE:              return false;
9227                 case EXPR_UNARY_PLUS:                return false;
9228                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
9229                 case EXPR_UNARY_NOT:                 return false;
9230                 case EXPR_UNARY_DEREFERENCE:         return false;
9231                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
9232                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
9233                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
9234                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
9235                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
9236
9237                 /* Treat void casts as if they have an effect in order to being able to
9238                  * suppress the warning */
9239                 case EXPR_UNARY_CAST: {
9240                         type_t *const type = skip_typeref(expr->base.type);
9241                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
9242                 }
9243
9244                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
9245                 case EXPR_UNARY_ASSUME:              return true;
9246                 case EXPR_UNARY_DELETE:              return true;
9247                 case EXPR_UNARY_DELETE_ARRAY:        return true;
9248                 case EXPR_UNARY_THROW:               return true;
9249
9250                 case EXPR_BINARY_ADD:                return false;
9251                 case EXPR_BINARY_SUB:                return false;
9252                 case EXPR_BINARY_MUL:                return false;
9253                 case EXPR_BINARY_DIV:                return false;
9254                 case EXPR_BINARY_MOD:                return false;
9255                 case EXPR_BINARY_EQUAL:              return false;
9256                 case EXPR_BINARY_NOTEQUAL:           return false;
9257                 case EXPR_BINARY_LESS:               return false;
9258                 case EXPR_BINARY_LESSEQUAL:          return false;
9259                 case EXPR_BINARY_GREATER:            return false;
9260                 case EXPR_BINARY_GREATEREQUAL:       return false;
9261                 case EXPR_BINARY_BITWISE_AND:        return false;
9262                 case EXPR_BINARY_BITWISE_OR:         return false;
9263                 case EXPR_BINARY_BITWISE_XOR:        return false;
9264                 case EXPR_BINARY_SHIFTLEFT:          return false;
9265                 case EXPR_BINARY_SHIFTRIGHT:         return false;
9266                 case EXPR_BINARY_ASSIGN:             return true;
9267                 case EXPR_BINARY_MUL_ASSIGN:         return true;
9268                 case EXPR_BINARY_DIV_ASSIGN:         return true;
9269                 case EXPR_BINARY_MOD_ASSIGN:         return true;
9270                 case EXPR_BINARY_ADD_ASSIGN:         return true;
9271                 case EXPR_BINARY_SUB_ASSIGN:         return true;
9272                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
9273                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
9274                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
9275                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
9276                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
9277
9278                 /* Only examine the right hand side of && and ||, because the left hand
9279                  * side already has the effect of controlling the execution of the right
9280                  * hand side */
9281                 case EXPR_BINARY_LOGICAL_AND:
9282                 case EXPR_BINARY_LOGICAL_OR:
9283                 /* Only examine the right hand side of a comma expression, because the left
9284                  * hand side has a separate warning */
9285                 case EXPR_BINARY_COMMA:
9286                         return expression_has_effect(expr->binary.right);
9287
9288                 case EXPR_BINARY_ISGREATER:          return false;
9289                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
9290                 case EXPR_BINARY_ISLESS:             return false;
9291                 case EXPR_BINARY_ISLESSEQUAL:        return false;
9292                 case EXPR_BINARY_ISLESSGREATER:      return false;
9293                 case EXPR_BINARY_ISUNORDERED:        return false;
9294         }
9295
9296         internal_errorf(HERE, "unexpected expression");
9297 }
9298
9299 static void semantic_comma(binary_expression_t *expression)
9300 {
9301         if (warning.unused_value) {
9302                 const expression_t *const left = expression->left;
9303                 if (!expression_has_effect(left)) {
9304                         warningf(&left->base.source_position,
9305                                  "left-hand operand of comma expression has no effect");
9306                 }
9307         }
9308         expression->base.type = expression->right->base.type;
9309 }
9310
9311 /**
9312  * @param prec_r precedence of the right operand
9313  */
9314 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, prec_r, sfunc) \
9315 static expression_t *parse_##binexpression_type(expression_t *left)          \
9316 {                                                                            \
9317         expression_t *binexpr = allocate_expression_zero(binexpression_type);    \
9318         binexpr->binary.left  = left;                                            \
9319         eat(token_type);                                                         \
9320                                                                              \
9321         expression_t *right = parse_sub_expression(prec_r);                      \
9322                                                                              \
9323         binexpr->binary.right = right;                                           \
9324         sfunc(&binexpr->binary);                                                 \
9325                                                                              \
9326         return binexpr;                                                          \
9327 }
9328
9329 CREATE_BINEXPR_PARSER('*',                    EXPR_BINARY_MUL,                PREC_CAST,           semantic_binexpr_arithmetic)
9330 CREATE_BINEXPR_PARSER('/',                    EXPR_BINARY_DIV,                PREC_CAST,           semantic_divmod_arithmetic)
9331 CREATE_BINEXPR_PARSER('%',                    EXPR_BINARY_MOD,                PREC_CAST,           semantic_divmod_arithmetic)
9332 CREATE_BINEXPR_PARSER('+',                    EXPR_BINARY_ADD,                PREC_MULTIPLICATIVE, semantic_add)
9333 CREATE_BINEXPR_PARSER('-',                    EXPR_BINARY_SUB,                PREC_MULTIPLICATIVE, semantic_sub)
9334 CREATE_BINEXPR_PARSER(T_LESSLESS,             EXPR_BINARY_SHIFTLEFT,          PREC_ADDITIVE,       semantic_shift_op)
9335 CREATE_BINEXPR_PARSER(T_GREATERGREATER,       EXPR_BINARY_SHIFTRIGHT,         PREC_ADDITIVE,       semantic_shift_op)
9336 CREATE_BINEXPR_PARSER('<',                    EXPR_BINARY_LESS,               PREC_SHIFT,          semantic_comparison)
9337 CREATE_BINEXPR_PARSER('>',                    EXPR_BINARY_GREATER,            PREC_SHIFT,          semantic_comparison)
9338 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,          PREC_SHIFT,          semantic_comparison)
9339 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,       PREC_SHIFT,          semantic_comparison)
9340 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,           PREC_RELATIONAL,     semantic_comparison)
9341 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,              PREC_RELATIONAL,     semantic_comparison)
9342 CREATE_BINEXPR_PARSER('&',                    EXPR_BINARY_BITWISE_AND,        PREC_EQUALITY,       semantic_binexpr_arithmetic)
9343 CREATE_BINEXPR_PARSER('^',                    EXPR_BINARY_BITWISE_XOR,        PREC_AND,            semantic_binexpr_arithmetic)
9344 CREATE_BINEXPR_PARSER('|',                    EXPR_BINARY_BITWISE_OR,         PREC_XOR,            semantic_binexpr_arithmetic)
9345 CREATE_BINEXPR_PARSER(T_ANDAND,               EXPR_BINARY_LOGICAL_AND,        PREC_OR,             semantic_logical_op)
9346 CREATE_BINEXPR_PARSER(T_PIPEPIPE,             EXPR_BINARY_LOGICAL_OR,         PREC_LOGICAL_AND,    semantic_logical_op)
9347 CREATE_BINEXPR_PARSER('=',                    EXPR_BINARY_ASSIGN,             PREC_ASSIGNMENT,     semantic_binexpr_assign)
9348 CREATE_BINEXPR_PARSER(T_PLUSEQUAL,            EXPR_BINARY_ADD_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9349 CREATE_BINEXPR_PARSER(T_MINUSEQUAL,           EXPR_BINARY_SUB_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9350 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL,        EXPR_BINARY_MUL_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9351 CREATE_BINEXPR_PARSER(T_SLASHEQUAL,           EXPR_BINARY_DIV_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9352 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL,         EXPR_BINARY_MOD_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9353 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL,        EXPR_BINARY_SHIFTLEFT_ASSIGN,   PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9354 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL,  EXPR_BINARY_SHIFTRIGHT_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9355 CREATE_BINEXPR_PARSER(T_ANDEQUAL,             EXPR_BINARY_BITWISE_AND_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9356 CREATE_BINEXPR_PARSER(T_PIPEEQUAL,            EXPR_BINARY_BITWISE_OR_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9357 CREATE_BINEXPR_PARSER(T_CARETEQUAL,           EXPR_BINARY_BITWISE_XOR_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9358 CREATE_BINEXPR_PARSER(',',                    EXPR_BINARY_COMMA,              PREC_ASSIGNMENT,     semantic_comma)
9359
9360
9361 static expression_t *parse_sub_expression(precedence_t precedence)
9362 {
9363         if (token.type < 0) {
9364                 return expected_expression_error();
9365         }
9366
9367         expression_parser_function_t *parser
9368                 = &expression_parsers[token.type];
9369         source_position_t             source_position = token.source_position;
9370         expression_t                 *left;
9371
9372         if (parser->parser != NULL) {
9373                 left = parser->parser();
9374         } else {
9375                 left = parse_primary_expression();
9376         }
9377         assert(left != NULL);
9378         left->base.source_position = source_position;
9379
9380         while (true) {
9381                 if (token.type < 0) {
9382                         return expected_expression_error();
9383                 }
9384
9385                 parser = &expression_parsers[token.type];
9386                 if (parser->infix_parser == NULL)
9387                         break;
9388                 if (parser->infix_precedence < precedence)
9389                         break;
9390
9391                 left = parser->infix_parser(left);
9392
9393                 assert(left != NULL);
9394                 assert(left->kind != EXPR_UNKNOWN);
9395                 left->base.source_position = source_position;
9396         }
9397
9398         return left;
9399 }
9400
9401 /**
9402  * Parse an expression.
9403  */
9404 static expression_t *parse_expression(void)
9405 {
9406         return parse_sub_expression(PREC_EXPRESSION);
9407 }
9408
9409 /**
9410  * Register a parser for a prefix-like operator.
9411  *
9412  * @param parser      the parser function
9413  * @param token_type  the token type of the prefix token
9414  */
9415 static void register_expression_parser(parse_expression_function parser,
9416                                        int token_type)
9417 {
9418         expression_parser_function_t *entry = &expression_parsers[token_type];
9419
9420         if (entry->parser != NULL) {
9421                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9422                 panic("trying to register multiple expression parsers for a token");
9423         }
9424         entry->parser = parser;
9425 }
9426
9427 /**
9428  * Register a parser for an infix operator with given precedence.
9429  *
9430  * @param parser      the parser function
9431  * @param token_type  the token type of the infix operator
9432  * @param precedence  the precedence of the operator
9433  */
9434 static void register_infix_parser(parse_expression_infix_function parser,
9435                 int token_type, unsigned precedence)
9436 {
9437         expression_parser_function_t *entry = &expression_parsers[token_type];
9438
9439         if (entry->infix_parser != NULL) {
9440                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9441                 panic("trying to register multiple infix expression parsers for a "
9442                       "token");
9443         }
9444         entry->infix_parser     = parser;
9445         entry->infix_precedence = precedence;
9446 }
9447
9448 /**
9449  * Initialize the expression parsers.
9450  */
9451 static void init_expression_parsers(void)
9452 {
9453         memset(&expression_parsers, 0, sizeof(expression_parsers));
9454
9455         register_infix_parser(parse_array_expression,               '[',                    PREC_POSTFIX);
9456         register_infix_parser(parse_call_expression,                '(',                    PREC_POSTFIX);
9457         register_infix_parser(parse_select_expression,              '.',                    PREC_POSTFIX);
9458         register_infix_parser(parse_select_expression,              T_MINUSGREATER,         PREC_POSTFIX);
9459         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,   T_PLUSPLUS,             PREC_POSTFIX);
9460         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,   T_MINUSMINUS,           PREC_POSTFIX);
9461         register_infix_parser(parse_EXPR_BINARY_MUL,                '*',                    PREC_MULTIPLICATIVE);
9462         register_infix_parser(parse_EXPR_BINARY_DIV,                '/',                    PREC_MULTIPLICATIVE);
9463         register_infix_parser(parse_EXPR_BINARY_MOD,                '%',                    PREC_MULTIPLICATIVE);
9464         register_infix_parser(parse_EXPR_BINARY_ADD,                '+',                    PREC_ADDITIVE);
9465         register_infix_parser(parse_EXPR_BINARY_SUB,                '-',                    PREC_ADDITIVE);
9466         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,          T_LESSLESS,             PREC_SHIFT);
9467         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,         T_GREATERGREATER,       PREC_SHIFT);
9468         register_infix_parser(parse_EXPR_BINARY_LESS,               '<',                    PREC_RELATIONAL);
9469         register_infix_parser(parse_EXPR_BINARY_GREATER,            '>',                    PREC_RELATIONAL);
9470         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,          T_LESSEQUAL,            PREC_RELATIONAL);
9471         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL,       T_GREATEREQUAL,         PREC_RELATIONAL);
9472         register_infix_parser(parse_EXPR_BINARY_EQUAL,              T_EQUALEQUAL,           PREC_EQUALITY);
9473         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,           T_EXCLAMATIONMARKEQUAL, PREC_EQUALITY);
9474         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,        '&',                    PREC_AND);
9475         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,        '^',                    PREC_XOR);
9476         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,         '|',                    PREC_OR);
9477         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,        T_ANDAND,               PREC_LOGICAL_AND);
9478         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,         T_PIPEPIPE,             PREC_LOGICAL_OR);
9479         register_infix_parser(parse_conditional_expression,         '?',                    PREC_CONDITIONAL);
9480         register_infix_parser(parse_EXPR_BINARY_ASSIGN,             '=',                    PREC_ASSIGNMENT);
9481         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,         T_PLUSEQUAL,            PREC_ASSIGNMENT);
9482         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,         T_MINUSEQUAL,           PREC_ASSIGNMENT);
9483         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,         T_ASTERISKEQUAL,        PREC_ASSIGNMENT);
9484         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,         T_SLASHEQUAL,           PREC_ASSIGNMENT);
9485         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,         T_PERCENTEQUAL,         PREC_ASSIGNMENT);
9486         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,   T_LESSLESSEQUAL,        PREC_ASSIGNMENT);
9487         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,  T_GREATERGREATEREQUAL,  PREC_ASSIGNMENT);
9488         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN, T_ANDEQUAL,             PREC_ASSIGNMENT);
9489         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,  T_PIPEEQUAL,            PREC_ASSIGNMENT);
9490         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN, T_CARETEQUAL,           PREC_ASSIGNMENT);
9491         register_infix_parser(parse_EXPR_BINARY_COMMA,              ',',                    PREC_EXPRESSION);
9492
9493         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-');
9494         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+');
9495         register_expression_parser(parse_EXPR_UNARY_NOT,              '!');
9496         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~');
9497         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*');
9498         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&');
9499         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT, T_PLUSPLUS);
9500         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT, T_MINUSMINUS);
9501         register_expression_parser(parse_sizeof,                      T_sizeof);
9502         register_expression_parser(parse_alignof,                     T___alignof__);
9503         register_expression_parser(parse_extension,                   T___extension__);
9504         register_expression_parser(parse_builtin_classify_type,       T___builtin_classify_type);
9505         register_expression_parser(parse_delete,                      T_delete);
9506         register_expression_parser(parse_throw,                       T_throw);
9507 }
9508
9509 /**
9510  * Parse a asm statement arguments specification.
9511  */
9512 static asm_argument_t *parse_asm_arguments(bool is_out)
9513 {
9514         asm_argument_t  *result = NULL;
9515         asm_argument_t **anchor = &result;
9516
9517         while (token.type == T_STRING_LITERAL || token.type == '[') {
9518                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
9519                 memset(argument, 0, sizeof(argument[0]));
9520
9521                 if (token.type == '[') {
9522                         eat('[');
9523                         if (token.type != T_IDENTIFIER) {
9524                                 parse_error_expected("while parsing asm argument",
9525                                                      T_IDENTIFIER, NULL);
9526                                 return NULL;
9527                         }
9528                         argument->symbol = token.v.symbol;
9529
9530                         expect(']');
9531                 }
9532
9533                 argument->constraints = parse_string_literals();
9534                 expect('(');
9535                 add_anchor_token(')');
9536                 expression_t *expression = parse_expression();
9537                 rem_anchor_token(')');
9538                 if (is_out) {
9539                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
9540                          * change size or type representation (e.g. int -> long is ok, but
9541                          * int -> float is not) */
9542                         if (expression->kind == EXPR_UNARY_CAST) {
9543                                 type_t      *const type = expression->base.type;
9544                                 type_kind_t  const kind = type->kind;
9545                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
9546                                         unsigned flags;
9547                                         unsigned size;
9548                                         if (kind == TYPE_ATOMIC) {
9549                                                 atomic_type_kind_t const akind = type->atomic.akind;
9550                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9551                                                 size  = get_atomic_type_size(akind);
9552                                         } else {
9553                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9554                                                 size  = get_atomic_type_size(get_intptr_kind());
9555                                         }
9556
9557                                         do {
9558                                                 expression_t *const value      = expression->unary.value;
9559                                                 type_t       *const value_type = value->base.type;
9560                                                 type_kind_t   const value_kind = value_type->kind;
9561
9562                                                 unsigned value_flags;
9563                                                 unsigned value_size;
9564                                                 if (value_kind == TYPE_ATOMIC) {
9565                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
9566                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9567                                                         value_size  = get_atomic_type_size(value_akind);
9568                                                 } else if (value_kind == TYPE_POINTER) {
9569                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9570                                                         value_size  = get_atomic_type_size(get_intptr_kind());
9571                                                 } else {
9572                                                         break;
9573                                                 }
9574
9575                                                 if (value_flags != flags || value_size != size)
9576                                                         break;
9577
9578                                                 expression = value;
9579                                         } while (expression->kind == EXPR_UNARY_CAST);
9580                                 }
9581                         }
9582
9583                         if (!is_lvalue(expression)) {
9584                                 errorf(&expression->base.source_position,
9585                                        "asm output argument is not an lvalue");
9586                         }
9587
9588                         if (argument->constraints.begin[0] == '+')
9589                                 mark_vars_read(expression, NULL);
9590                 } else {
9591                         mark_vars_read(expression, NULL);
9592                 }
9593                 argument->expression = expression;
9594                 expect(')');
9595
9596                 set_address_taken(expression, true);
9597
9598                 *anchor = argument;
9599                 anchor  = &argument->next;
9600
9601                 if (token.type != ',')
9602                         break;
9603                 eat(',');
9604         }
9605
9606         return result;
9607 end_error:
9608         return NULL;
9609 }
9610
9611 /**
9612  * Parse a asm statement clobber specification.
9613  */
9614 static asm_clobber_t *parse_asm_clobbers(void)
9615 {
9616         asm_clobber_t *result = NULL;
9617         asm_clobber_t *last   = NULL;
9618
9619         while (token.type == T_STRING_LITERAL) {
9620                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
9621                 clobber->clobber       = parse_string_literals();
9622
9623                 if (last != NULL) {
9624                         last->next = clobber;
9625                 } else {
9626                         result = clobber;
9627                 }
9628                 last = clobber;
9629
9630                 if (token.type != ',')
9631                         break;
9632                 eat(',');
9633         }
9634
9635         return result;
9636 }
9637
9638 /**
9639  * Parse an asm statement.
9640  */
9641 static statement_t *parse_asm_statement(void)
9642 {
9643         statement_t     *statement     = allocate_statement_zero(STATEMENT_ASM);
9644         asm_statement_t *asm_statement = &statement->asms;
9645
9646         eat(T_asm);
9647
9648         if (token.type == T_volatile) {
9649                 next_token();
9650                 asm_statement->is_volatile = true;
9651         }
9652
9653         expect('(');
9654         add_anchor_token(')');
9655         add_anchor_token(':');
9656         asm_statement->asm_text = parse_string_literals();
9657
9658         if (token.type != ':') {
9659                 rem_anchor_token(':');
9660                 goto end_of_asm;
9661         }
9662         eat(':');
9663
9664         asm_statement->outputs = parse_asm_arguments(true);
9665         if (token.type != ':') {
9666                 rem_anchor_token(':');
9667                 goto end_of_asm;
9668         }
9669         eat(':');
9670
9671         asm_statement->inputs = parse_asm_arguments(false);
9672         if (token.type != ':') {
9673                 rem_anchor_token(':');
9674                 goto end_of_asm;
9675         }
9676         rem_anchor_token(':');
9677         eat(':');
9678
9679         asm_statement->clobbers = parse_asm_clobbers();
9680
9681 end_of_asm:
9682         rem_anchor_token(')');
9683         expect(')');
9684         expect(';');
9685
9686         if (asm_statement->outputs == NULL) {
9687                 /* GCC: An 'asm' instruction without any output operands will be treated
9688                  * identically to a volatile 'asm' instruction. */
9689                 asm_statement->is_volatile = true;
9690         }
9691
9692         return statement;
9693 end_error:
9694         return create_invalid_statement();
9695 }
9696
9697 /**
9698  * Parse a case statement.
9699  */
9700 static statement_t *parse_case_statement(void)
9701 {
9702         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9703         source_position_t *const pos       = &statement->base.source_position;
9704
9705         eat(T_case);
9706
9707         expression_t *const expression   = parse_expression();
9708         statement->case_label.expression = expression;
9709         if (!is_constant_expression(expression)) {
9710                 /* This check does not prevent the error message in all cases of an
9711                  * prior error while parsing the expression.  At least it catches the
9712                  * common case of a mistyped enum entry. */
9713                 if (is_type_valid(skip_typeref(expression->base.type))) {
9714                         errorf(pos, "case label does not reduce to an integer constant");
9715                 }
9716                 statement->case_label.is_bad = true;
9717         } else {
9718                 long const val = fold_constant(expression);
9719                 statement->case_label.first_case = val;
9720                 statement->case_label.last_case  = val;
9721         }
9722
9723         if (GNU_MODE) {
9724                 if (token.type == T_DOTDOTDOT) {
9725                         next_token();
9726                         expression_t *const end_range   = parse_expression();
9727                         statement->case_label.end_range = end_range;
9728                         if (!is_constant_expression(end_range)) {
9729                                 /* This check does not prevent the error message in all cases of an
9730                                  * prior error while parsing the expression.  At least it catches the
9731                                  * common case of a mistyped enum entry. */
9732                                 if (is_type_valid(skip_typeref(end_range->base.type))) {
9733                                         errorf(pos, "case range does not reduce to an integer constant");
9734                                 }
9735                                 statement->case_label.is_bad = true;
9736                         } else {
9737                                 long const val = fold_constant(end_range);
9738                                 statement->case_label.last_case = val;
9739
9740                                 if (warning.other && val < statement->case_label.first_case) {
9741                                         statement->case_label.is_empty_range = true;
9742                                         warningf(pos, "empty range specified");
9743                                 }
9744                         }
9745                 }
9746         }
9747
9748         PUSH_PARENT(statement);
9749
9750         expect(':');
9751 end_error:
9752
9753         if (current_switch != NULL) {
9754                 if (! statement->case_label.is_bad) {
9755                         /* Check for duplicate case values */
9756                         case_label_statement_t *c = &statement->case_label;
9757                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
9758                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
9759                                         continue;
9760
9761                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
9762                                         continue;
9763
9764                                 errorf(pos, "duplicate case value (previously used %P)",
9765                                        &l->base.source_position);
9766                                 break;
9767                         }
9768                 }
9769                 /* link all cases into the switch statement */
9770                 if (current_switch->last_case == NULL) {
9771                         current_switch->first_case      = &statement->case_label;
9772                 } else {
9773                         current_switch->last_case->next = &statement->case_label;
9774                 }
9775                 current_switch->last_case = &statement->case_label;
9776         } else {
9777                 errorf(pos, "case label not within a switch statement");
9778         }
9779
9780         statement_t *const inner_stmt = parse_statement();
9781         statement->case_label.statement = inner_stmt;
9782         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9783                 errorf(&inner_stmt->base.source_position, "declaration after case label");
9784         }
9785
9786         POP_PARENT;
9787         return statement;
9788 }
9789
9790 /**
9791  * Parse a default statement.
9792  */
9793 static statement_t *parse_default_statement(void)
9794 {
9795         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9796
9797         eat(T_default);
9798
9799         PUSH_PARENT(statement);
9800
9801         expect(':');
9802         if (current_switch != NULL) {
9803                 const case_label_statement_t *def_label = current_switch->default_label;
9804                 if (def_label != NULL) {
9805                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
9806                                &def_label->base.source_position);
9807                 } else {
9808                         current_switch->default_label = &statement->case_label;
9809
9810                         /* link all cases into the switch statement */
9811                         if (current_switch->last_case == NULL) {
9812                                 current_switch->first_case      = &statement->case_label;
9813                         } else {
9814                                 current_switch->last_case->next = &statement->case_label;
9815                         }
9816                         current_switch->last_case = &statement->case_label;
9817                 }
9818         } else {
9819                 errorf(&statement->base.source_position,
9820                         "'default' label not within a switch statement");
9821         }
9822
9823         statement_t *const inner_stmt = parse_statement();
9824         statement->case_label.statement = inner_stmt;
9825         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9826                 errorf(&inner_stmt->base.source_position, "declaration after default label");
9827         }
9828
9829         POP_PARENT;
9830         return statement;
9831 end_error:
9832         POP_PARENT;
9833         return create_invalid_statement();
9834 }
9835
9836 /**
9837  * Parse a label statement.
9838  */
9839 static statement_t *parse_label_statement(void)
9840 {
9841         assert(token.type == T_IDENTIFIER);
9842         symbol_t *symbol = token.v.symbol;
9843         label_t  *label  = get_label(symbol);
9844
9845         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
9846         statement->label.label       = label;
9847
9848         next_token();
9849
9850         PUSH_PARENT(statement);
9851
9852         /* if statement is already set then the label is defined twice,
9853          * otherwise it was just mentioned in a goto/local label declaration so far
9854          */
9855         if (label->statement != NULL) {
9856                 errorf(HERE, "duplicate label '%Y' (declared %P)",
9857                        symbol, &label->base.source_position);
9858         } else {
9859                 label->base.source_position = token.source_position;
9860                 label->statement            = statement;
9861         }
9862
9863         eat(':');
9864
9865         if (token.type == '}') {
9866                 /* TODO only warn? */
9867                 if (warning.other && false) {
9868                         warningf(HERE, "label at end of compound statement");
9869                         statement->label.statement = create_empty_statement();
9870                 } else {
9871                         errorf(HERE, "label at end of compound statement");
9872                         statement->label.statement = create_invalid_statement();
9873                 }
9874         } else if (token.type == ';') {
9875                 /* Eat an empty statement here, to avoid the warning about an empty
9876                  * statement after a label.  label:; is commonly used to have a label
9877                  * before a closing brace. */
9878                 statement->label.statement = create_empty_statement();
9879                 next_token();
9880         } else {
9881                 statement_t *const inner_stmt = parse_statement();
9882                 statement->label.statement = inner_stmt;
9883                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
9884                         errorf(&inner_stmt->base.source_position, "declaration after label");
9885                 }
9886         }
9887
9888         /* remember the labels in a list for later checking */
9889         *label_anchor = &statement->label;
9890         label_anchor  = &statement->label.next;
9891
9892         POP_PARENT;
9893         return statement;
9894 }
9895
9896 /**
9897  * Parse an if statement.
9898  */
9899 static statement_t *parse_if(void)
9900 {
9901         statement_t *statement = allocate_statement_zero(STATEMENT_IF);
9902
9903         eat(T_if);
9904
9905         PUSH_PARENT(statement);
9906
9907         add_anchor_token('{');
9908
9909         expect('(');
9910         add_anchor_token(')');
9911         expression_t *const expr = parse_expression();
9912         statement->ifs.condition = expr;
9913         /* §6.8.4.1:1  The controlling expression of an if statement shall have
9914          *             scalar type. */
9915         semantic_condition(expr, "condition of 'if'-statment");
9916         mark_vars_read(expr, NULL);
9917         rem_anchor_token(')');
9918         expect(')');
9919
9920 end_error:
9921         rem_anchor_token('{');
9922
9923         add_anchor_token(T_else);
9924         statement->ifs.true_statement = parse_statement();
9925         rem_anchor_token(T_else);
9926
9927         if (token.type == T_else) {
9928                 next_token();
9929                 statement->ifs.false_statement = parse_statement();
9930         }
9931
9932         POP_PARENT;
9933         return statement;
9934 }
9935
9936 /**
9937  * Check that all enums are handled in a switch.
9938  *
9939  * @param statement  the switch statement to check
9940  */
9941 static void check_enum_cases(const switch_statement_t *statement) {
9942         const type_t *type = skip_typeref(statement->expression->base.type);
9943         if (! is_type_enum(type))
9944                 return;
9945         const enum_type_t *enumt = &type->enumt;
9946
9947         /* if we have a default, no warnings */
9948         if (statement->default_label != NULL)
9949                 return;
9950
9951         /* FIXME: calculation of value should be done while parsing */
9952         /* TODO: quadratic algorithm here. Change to an n log n one */
9953         long            last_value = -1;
9954         const entity_t *entry      = enumt->enume->base.next;
9955         for (; entry != NULL && entry->kind == ENTITY_ENUM_VALUE;
9956              entry = entry->base.next) {
9957                 const expression_t *expression = entry->enum_value.value;
9958                 long                value      = expression != NULL ? fold_constant(expression) : last_value + 1;
9959                 bool                found      = false;
9960                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
9961                         if (l->expression == NULL)
9962                                 continue;
9963                         if (l->first_case <= value && value <= l->last_case) {
9964                                 found = true;
9965                                 break;
9966                         }
9967                 }
9968                 if (! found) {
9969                         warningf(&statement->base.source_position,
9970                                  "enumeration value '%Y' not handled in switch",
9971                                  entry->base.symbol);
9972                 }
9973                 last_value = value;
9974         }
9975 }
9976
9977 /**
9978  * Parse a switch statement.
9979  */
9980 static statement_t *parse_switch(void)
9981 {
9982         statement_t *statement = allocate_statement_zero(STATEMENT_SWITCH);
9983
9984         eat(T_switch);
9985
9986         PUSH_PARENT(statement);
9987
9988         expect('(');
9989         add_anchor_token(')');
9990         expression_t *const expr = parse_expression();
9991         mark_vars_read(expr, NULL);
9992         type_t       *      type = skip_typeref(expr->base.type);
9993         if (is_type_integer(type)) {
9994                 type = promote_integer(type);
9995                 if (warning.traditional) {
9996                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
9997                                 warningf(&expr->base.source_position,
9998                                         "'%T' switch expression not converted to '%T' in ISO C",
9999                                         type, type_int);
10000                         }
10001                 }
10002         } else if (is_type_valid(type)) {
10003                 errorf(&expr->base.source_position,
10004                        "switch quantity is not an integer, but '%T'", type);
10005                 type = type_error_type;
10006         }
10007         statement->switchs.expression = create_implicit_cast(expr, type);
10008         expect(')');
10009         rem_anchor_token(')');
10010
10011         switch_statement_t *rem = current_switch;
10012         current_switch          = &statement->switchs;
10013         statement->switchs.body = parse_statement();
10014         current_switch          = rem;
10015
10016         if (warning.switch_default &&
10017             statement->switchs.default_label == NULL) {
10018                 warningf(&statement->base.source_position, "switch has no default case");
10019         }
10020         if (warning.switch_enum)
10021                 check_enum_cases(&statement->switchs);
10022
10023         POP_PARENT;
10024         return statement;
10025 end_error:
10026         POP_PARENT;
10027         return create_invalid_statement();
10028 }
10029
10030 static statement_t *parse_loop_body(statement_t *const loop)
10031 {
10032         statement_t *const rem = current_loop;
10033         current_loop = loop;
10034
10035         statement_t *const body = parse_statement();
10036
10037         current_loop = rem;
10038         return body;
10039 }
10040
10041 /**
10042  * Parse a while statement.
10043  */
10044 static statement_t *parse_while(void)
10045 {
10046         statement_t *statement = allocate_statement_zero(STATEMENT_WHILE);
10047
10048         eat(T_while);
10049
10050         PUSH_PARENT(statement);
10051
10052         expect('(');
10053         add_anchor_token(')');
10054         expression_t *const cond = parse_expression();
10055         statement->whiles.condition = cond;
10056         /* §6.8.5:2    The controlling expression of an iteration statement shall
10057          *             have scalar type. */
10058         semantic_condition(cond, "condition of 'while'-statement");
10059         mark_vars_read(cond, NULL);
10060         rem_anchor_token(')');
10061         expect(')');
10062
10063         statement->whiles.body = parse_loop_body(statement);
10064
10065         POP_PARENT;
10066         return statement;
10067 end_error:
10068         POP_PARENT;
10069         return create_invalid_statement();
10070 }
10071
10072 /**
10073  * Parse a do statement.
10074  */
10075 static statement_t *parse_do(void)
10076 {
10077         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
10078
10079         eat(T_do);
10080
10081         PUSH_PARENT(statement);
10082
10083         add_anchor_token(T_while);
10084         statement->do_while.body = parse_loop_body(statement);
10085         rem_anchor_token(T_while);
10086
10087         expect(T_while);
10088         expect('(');
10089         add_anchor_token(')');
10090         expression_t *const cond = parse_expression();
10091         statement->do_while.condition = cond;
10092         /* §6.8.5:2    The controlling expression of an iteration statement shall
10093          *             have scalar type. */
10094         semantic_condition(cond, "condition of 'do-while'-statement");
10095         mark_vars_read(cond, NULL);
10096         rem_anchor_token(')');
10097         expect(')');
10098         expect(';');
10099
10100         POP_PARENT;
10101         return statement;
10102 end_error:
10103         POP_PARENT;
10104         return create_invalid_statement();
10105 }
10106
10107 /**
10108  * Parse a for statement.
10109  */
10110 static statement_t *parse_for(void)
10111 {
10112         statement_t *statement = allocate_statement_zero(STATEMENT_FOR);
10113
10114         eat(T_for);
10115
10116         PUSH_PARENT(statement);
10117
10118         size_t const  top       = environment_top();
10119         scope_t      *old_scope = scope_push(&statement->fors.scope);
10120
10121         expect('(');
10122         add_anchor_token(')');
10123
10124         if (token.type == ';') {
10125                 next_token();
10126         } else if (is_declaration_specifier(&token, false)) {
10127                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10128         } else {
10129                 add_anchor_token(';');
10130                 expression_t *const init = parse_expression();
10131                 statement->fors.initialisation = init;
10132                 mark_vars_read(init, ENT_ANY);
10133                 if (warning.unused_value && !expression_has_effect(init)) {
10134                         warningf(&init->base.source_position,
10135                                         "initialisation of 'for'-statement has no effect");
10136                 }
10137                 rem_anchor_token(';');
10138                 expect(';');
10139         }
10140
10141         if (token.type != ';') {
10142                 add_anchor_token(';');
10143                 expression_t *const cond = parse_expression();
10144                 statement->fors.condition = cond;
10145                 /* §6.8.5:2    The controlling expression of an iteration statement
10146                  *             shall have scalar type. */
10147                 semantic_condition(cond, "condition of 'for'-statement");
10148                 mark_vars_read(cond, NULL);
10149                 rem_anchor_token(';');
10150         }
10151         expect(';');
10152         if (token.type != ')') {
10153                 expression_t *const step = parse_expression();
10154                 statement->fors.step = step;
10155                 mark_vars_read(step, ENT_ANY);
10156                 if (warning.unused_value && !expression_has_effect(step)) {
10157                         warningf(&step->base.source_position,
10158                                  "step of 'for'-statement has no effect");
10159                 }
10160         }
10161         expect(')');
10162         rem_anchor_token(')');
10163         statement->fors.body = parse_loop_body(statement);
10164
10165         assert(current_scope == &statement->fors.scope);
10166         scope_pop(old_scope);
10167         environment_pop_to(top);
10168
10169         POP_PARENT;
10170         return statement;
10171
10172 end_error:
10173         POP_PARENT;
10174         rem_anchor_token(')');
10175         assert(current_scope == &statement->fors.scope);
10176         scope_pop(old_scope);
10177         environment_pop_to(top);
10178
10179         return create_invalid_statement();
10180 }
10181
10182 /**
10183  * Parse a goto statement.
10184  */
10185 static statement_t *parse_goto(void)
10186 {
10187         statement_t *statement = allocate_statement_zero(STATEMENT_GOTO);
10188         eat(T_goto);
10189
10190         if (GNU_MODE && token.type == '*') {
10191                 next_token();
10192                 expression_t *expression = parse_expression();
10193                 mark_vars_read(expression, NULL);
10194
10195                 /* Argh: although documentation says the expression must be of type void*,
10196                  * gcc accepts anything that can be casted into void* without error */
10197                 type_t *type = expression->base.type;
10198
10199                 if (type != type_error_type) {
10200                         if (!is_type_pointer(type) && !is_type_integer(type)) {
10201                                 errorf(&expression->base.source_position,
10202                                         "cannot convert to a pointer type");
10203                         } else if (warning.other && type != type_void_ptr) {
10204                                 warningf(&expression->base.source_position,
10205                                         "type of computed goto expression should be 'void*' not '%T'", type);
10206                         }
10207                         expression = create_implicit_cast(expression, type_void_ptr);
10208                 }
10209
10210                 statement->gotos.expression = expression;
10211         } else {
10212                 if (token.type != T_IDENTIFIER) {
10213                         if (GNU_MODE)
10214                                 parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
10215                         else
10216                                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
10217                         eat_until_anchor();
10218                         goto end_error;
10219                 }
10220                 symbol_t *symbol = token.v.symbol;
10221                 next_token();
10222
10223                 statement->gotos.label = get_label(symbol);
10224         }
10225
10226         /* remember the goto's in a list for later checking */
10227         *goto_anchor = &statement->gotos;
10228         goto_anchor  = &statement->gotos.next;
10229
10230         expect(';');
10231
10232         return statement;
10233 end_error:
10234         return create_invalid_statement();
10235 }
10236
10237 /**
10238  * Parse a continue statement.
10239  */
10240 static statement_t *parse_continue(void)
10241 {
10242         if (current_loop == NULL) {
10243                 errorf(HERE, "continue statement not within loop");
10244         }
10245
10246         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
10247
10248         eat(T_continue);
10249         expect(';');
10250
10251 end_error:
10252         return statement;
10253 }
10254
10255 /**
10256  * Parse a break statement.
10257  */
10258 static statement_t *parse_break(void)
10259 {
10260         if (current_switch == NULL && current_loop == NULL) {
10261                 errorf(HERE, "break statement not within loop or switch");
10262         }
10263
10264         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
10265
10266         eat(T_break);
10267         expect(';');
10268
10269 end_error:
10270         return statement;
10271 }
10272
10273 /**
10274  * Parse a __leave statement.
10275  */
10276 static statement_t *parse_leave_statement(void)
10277 {
10278         if (current_try == NULL) {
10279                 errorf(HERE, "__leave statement not within __try");
10280         }
10281
10282         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
10283
10284         eat(T___leave);
10285         expect(';');
10286
10287 end_error:
10288         return statement;
10289 }
10290
10291 /**
10292  * Check if a given entity represents a local variable.
10293  */
10294 static bool is_local_variable(const entity_t *entity)
10295 {
10296         if (entity->kind != ENTITY_VARIABLE)
10297                 return false;
10298
10299         switch ((storage_class_tag_t) entity->declaration.storage_class) {
10300         case STORAGE_CLASS_AUTO:
10301         case STORAGE_CLASS_REGISTER: {
10302                 const type_t *type = skip_typeref(entity->declaration.type);
10303                 if (is_type_function(type)) {
10304                         return false;
10305                 } else {
10306                         return true;
10307                 }
10308         }
10309         default:
10310                 return false;
10311         }
10312 }
10313
10314 /**
10315  * Check if a given expression represents a local variable.
10316  */
10317 static bool expression_is_local_variable(const expression_t *expression)
10318 {
10319         if (expression->base.kind != EXPR_REFERENCE) {
10320                 return false;
10321         }
10322         const entity_t *entity = expression->reference.entity;
10323         return is_local_variable(entity);
10324 }
10325
10326 /**
10327  * Check if a given expression represents a local variable and
10328  * return its declaration then, else return NULL.
10329  */
10330 entity_t *expression_is_variable(const expression_t *expression)
10331 {
10332         if (expression->base.kind != EXPR_REFERENCE) {
10333                 return NULL;
10334         }
10335         entity_t *entity = expression->reference.entity;
10336         if (entity->kind != ENTITY_VARIABLE)
10337                 return NULL;
10338
10339         return entity;
10340 }
10341
10342 /**
10343  * Parse a return statement.
10344  */
10345 static statement_t *parse_return(void)
10346 {
10347         eat(T_return);
10348
10349         statement_t *statement = allocate_statement_zero(STATEMENT_RETURN);
10350
10351         expression_t *return_value = NULL;
10352         if (token.type != ';') {
10353                 return_value = parse_expression();
10354                 mark_vars_read(return_value, NULL);
10355         }
10356
10357         const type_t *const func_type = skip_typeref(current_function->base.type);
10358         assert(is_type_function(func_type));
10359         type_t *const return_type = skip_typeref(func_type->function.return_type);
10360
10361         if (return_value != NULL) {
10362                 type_t *return_value_type = skip_typeref(return_value->base.type);
10363
10364                 if (is_type_atomic(return_type,        ATOMIC_TYPE_VOID) &&
10365                                 !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
10366                         if (warning.other) {
10367                                 warningf(&statement->base.source_position,
10368                                                 "'return' with a value, in function returning void");
10369                         }
10370                         return_value = NULL;
10371                 } else {
10372                         assign_error_t error = semantic_assign(return_type, return_value);
10373                         report_assign_error(error, return_type, return_value, "'return'",
10374                                             &statement->base.source_position);
10375                         return_value = create_implicit_cast(return_value, return_type);
10376                 }
10377                 /* check for returning address of a local var */
10378                 if (warning.other && return_value != NULL
10379                                 && return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
10380                         const expression_t *expression = return_value->unary.value;
10381                         if (expression_is_local_variable(expression)) {
10382                                 warningf(&statement->base.source_position,
10383                                          "function returns address of local variable");
10384                         }
10385                 }
10386         } else if (warning.other && !is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10387                 warningf(&statement->base.source_position,
10388                                 "'return' without value, in function returning non-void");
10389         }
10390         statement->returns.value = return_value;
10391
10392         expect(';');
10393
10394 end_error:
10395         return statement;
10396 }
10397
10398 /**
10399  * Parse a declaration statement.
10400  */
10401 static statement_t *parse_declaration_statement(void)
10402 {
10403         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10404
10405         entity_t *before = current_scope->last_entity;
10406         if (GNU_MODE) {
10407                 parse_external_declaration();
10408         } else {
10409                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10410         }
10411
10412         if (before == NULL) {
10413                 statement->declaration.declarations_begin = current_scope->entities;
10414         } else {
10415                 statement->declaration.declarations_begin = before->base.next;
10416         }
10417         statement->declaration.declarations_end = current_scope->last_entity;
10418
10419         return statement;
10420 }
10421
10422 /**
10423  * Parse an expression statement, ie. expr ';'.
10424  */
10425 static statement_t *parse_expression_statement(void)
10426 {
10427         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10428
10429         expression_t *const expr         = parse_expression();
10430         statement->expression.expression = expr;
10431         mark_vars_read(expr, ENT_ANY);
10432
10433         expect(';');
10434
10435 end_error:
10436         return statement;
10437 }
10438
10439 /**
10440  * Parse a microsoft __try { } __finally { } or
10441  * __try{ } __except() { }
10442  */
10443 static statement_t *parse_ms_try_statment(void)
10444 {
10445         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
10446         eat(T___try);
10447
10448         PUSH_PARENT(statement);
10449
10450         ms_try_statement_t *rem = current_try;
10451         current_try = &statement->ms_try;
10452         statement->ms_try.try_statement = parse_compound_statement(false);
10453         current_try = rem;
10454
10455         POP_PARENT;
10456
10457         if (token.type == T___except) {
10458                 eat(T___except);
10459                 expect('(');
10460                 add_anchor_token(')');
10461                 expression_t *const expr = parse_expression();
10462                 mark_vars_read(expr, NULL);
10463                 type_t       *      type = skip_typeref(expr->base.type);
10464                 if (is_type_integer(type)) {
10465                         type = promote_integer(type);
10466                 } else if (is_type_valid(type)) {
10467                         errorf(&expr->base.source_position,
10468                                "__expect expression is not an integer, but '%T'", type);
10469                         type = type_error_type;
10470                 }
10471                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
10472                 rem_anchor_token(')');
10473                 expect(')');
10474                 statement->ms_try.final_statement = parse_compound_statement(false);
10475         } else if (token.type == T__finally) {
10476                 eat(T___finally);
10477                 statement->ms_try.final_statement = parse_compound_statement(false);
10478         } else {
10479                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
10480                 return create_invalid_statement();
10481         }
10482         return statement;
10483 end_error:
10484         return create_invalid_statement();
10485 }
10486
10487 static statement_t *parse_empty_statement(void)
10488 {
10489         if (warning.empty_statement) {
10490                 warningf(HERE, "statement is empty");
10491         }
10492         statement_t *const statement = create_empty_statement();
10493         eat(';');
10494         return statement;
10495 }
10496
10497 static statement_t *parse_local_label_declaration(void)
10498 {
10499         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10500
10501         eat(T___label__);
10502
10503         entity_t *begin = NULL, *end = NULL;
10504
10505         while (true) {
10506                 if (token.type != T_IDENTIFIER) {
10507                         parse_error_expected("while parsing local label declaration",
10508                                 T_IDENTIFIER, NULL);
10509                         goto end_error;
10510                 }
10511                 symbol_t *symbol = token.v.symbol;
10512                 entity_t *entity = get_entity(symbol, NAMESPACE_LABEL);
10513                 if (entity != NULL && entity->base.parent_scope == current_scope) {
10514                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition %P)",
10515                                symbol, &entity->base.source_position);
10516                 } else {
10517                         entity = allocate_entity_zero(ENTITY_LOCAL_LABEL);
10518
10519                         entity->base.parent_scope    = current_scope;
10520                         entity->base.namespc         = NAMESPACE_LABEL;
10521                         entity->base.source_position = token.source_position;
10522                         entity->base.symbol          = symbol;
10523
10524                         if (end != NULL)
10525                                 end->base.next = entity;
10526                         end = entity;
10527                         if (begin == NULL)
10528                                 begin = entity;
10529
10530                         environment_push(entity);
10531                 }
10532                 next_token();
10533
10534                 if (token.type != ',')
10535                         break;
10536                 next_token();
10537         }
10538         eat(';');
10539 end_error:
10540         statement->declaration.declarations_begin = begin;
10541         statement->declaration.declarations_end   = end;
10542         return statement;
10543 }
10544
10545 static void parse_namespace_definition(void)
10546 {
10547         eat(T_namespace);
10548
10549         entity_t *entity = NULL;
10550         symbol_t *symbol = NULL;
10551
10552         if (token.type == T_IDENTIFIER) {
10553                 symbol = token.v.symbol;
10554                 next_token();
10555
10556                 entity = get_entity(symbol, NAMESPACE_NORMAL);
10557                 if (entity != NULL && entity->kind != ENTITY_NAMESPACE
10558                                 && entity->base.parent_scope == current_scope) {
10559                         error_redefined_as_different_kind(&token.source_position,
10560                                                           entity, ENTITY_NAMESPACE);
10561                         entity = NULL;
10562                 }
10563         }
10564
10565         if (entity == NULL) {
10566                 entity                       = allocate_entity_zero(ENTITY_NAMESPACE);
10567                 entity->base.symbol          = symbol;
10568                 entity->base.source_position = token.source_position;
10569                 entity->base.namespc         = NAMESPACE_NORMAL;
10570                 entity->base.parent_scope    = current_scope;
10571         }
10572
10573         if (token.type == '=') {
10574                 /* TODO: parse namespace alias */
10575                 panic("namespace alias definition not supported yet");
10576         }
10577
10578         environment_push(entity);
10579         append_entity(current_scope, entity);
10580
10581         size_t const  top       = environment_top();
10582         scope_t      *old_scope = scope_push(&entity->namespacee.members);
10583
10584         expect('{');
10585         parse_externals();
10586         expect('}');
10587
10588 end_error:
10589         assert(current_scope == &entity->namespacee.members);
10590         scope_pop(old_scope);
10591         environment_pop_to(top);
10592 }
10593
10594 /**
10595  * Parse a statement.
10596  * There's also parse_statement() which additionally checks for
10597  * "statement has no effect" warnings
10598  */
10599 static statement_t *intern_parse_statement(void)
10600 {
10601         statement_t *statement = NULL;
10602
10603         /* declaration or statement */
10604         add_anchor_token(';');
10605         switch (token.type) {
10606         case T_IDENTIFIER: {
10607                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
10608                 if (la1_type == ':') {
10609                         statement = parse_label_statement();
10610                 } else if (is_typedef_symbol(token.v.symbol)) {
10611                         statement = parse_declaration_statement();
10612                 } else {
10613                         /* it's an identifier, the grammar says this must be an
10614                          * expression statement. However it is common that users mistype
10615                          * declaration types, so we guess a bit here to improve robustness
10616                          * for incorrect programs */
10617                         switch (la1_type) {
10618                         case '&':
10619                         case '*':
10620                                 if (get_entity(token.v.symbol, NAMESPACE_NORMAL) != NULL)
10621                                         goto expression_statment;
10622                                 /* FALLTHROUGH */
10623
10624                         DECLARATION_START
10625                         case T_IDENTIFIER:
10626                                 statement = parse_declaration_statement();
10627                                 break;
10628
10629                         default:
10630 expression_statment:
10631                                 statement = parse_expression_statement();
10632                                 break;
10633                         }
10634                 }
10635                 break;
10636         }
10637
10638         case T___extension__:
10639                 /* This can be a prefix to a declaration or an expression statement.
10640                  * We simply eat it now and parse the rest with tail recursion. */
10641                 do {
10642                         next_token();
10643                 } while (token.type == T___extension__);
10644                 bool old_gcc_extension = in_gcc_extension;
10645                 in_gcc_extension       = true;
10646                 statement = intern_parse_statement();
10647                 in_gcc_extension = old_gcc_extension;
10648                 break;
10649
10650         DECLARATION_START
10651                 statement = parse_declaration_statement();
10652                 break;
10653
10654         case T___label__:
10655                 statement = parse_local_label_declaration();
10656                 break;
10657
10658         case ';':         statement = parse_empty_statement();         break;
10659         case '{':         statement = parse_compound_statement(false); break;
10660         case T___leave:   statement = parse_leave_statement();         break;
10661         case T___try:     statement = parse_ms_try_statment();         break;
10662         case T_asm:       statement = parse_asm_statement();           break;
10663         case T_break:     statement = parse_break();                   break;
10664         case T_case:      statement = parse_case_statement();          break;
10665         case T_continue:  statement = parse_continue();                break;
10666         case T_default:   statement = parse_default_statement();       break;
10667         case T_do:        statement = parse_do();                      break;
10668         case T_for:       statement = parse_for();                     break;
10669         case T_goto:      statement = parse_goto();                    break;
10670         case T_if:        statement = parse_if();                      break;
10671         case T_return:    statement = parse_return();                  break;
10672         case T_switch:    statement = parse_switch();                  break;
10673         case T_while:     statement = parse_while();                   break;
10674
10675         EXPRESSION_START
10676                 statement = parse_expression_statement();
10677                 break;
10678
10679         default:
10680                 errorf(HERE, "unexpected token %K while parsing statement", &token);
10681                 statement = create_invalid_statement();
10682                 if (!at_anchor())
10683                         next_token();
10684                 break;
10685         }
10686         rem_anchor_token(';');
10687
10688         assert(statement != NULL
10689                         && statement->base.source_position.input_name != NULL);
10690
10691         return statement;
10692 }
10693
10694 /**
10695  * parse a statement and emits "statement has no effect" warning if needed
10696  * (This is really a wrapper around intern_parse_statement with check for 1
10697  *  single warning. It is needed, because for statement expressions we have
10698  *  to avoid the warning on the last statement)
10699  */
10700 static statement_t *parse_statement(void)
10701 {
10702         statement_t *statement = intern_parse_statement();
10703
10704         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
10705                 expression_t *expression = statement->expression.expression;
10706                 if (!expression_has_effect(expression)) {
10707                         warningf(&expression->base.source_position,
10708                                         "statement has no effect");
10709                 }
10710         }
10711
10712         return statement;
10713 }
10714
10715 /**
10716  * Parse a compound statement.
10717  */
10718 static statement_t *parse_compound_statement(bool inside_expression_statement)
10719 {
10720         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
10721
10722         PUSH_PARENT(statement);
10723
10724         eat('{');
10725         add_anchor_token('}');
10726
10727         size_t const  top       = environment_top();
10728         scope_t      *old_scope = scope_push(&statement->compound.scope);
10729
10730         statement_t **anchor            = &statement->compound.statements;
10731         bool          only_decls_so_far = true;
10732         while (token.type != '}') {
10733                 if (token.type == T_EOF) {
10734                         errorf(&statement->base.source_position,
10735                                "EOF while parsing compound statement");
10736                         break;
10737                 }
10738                 statement_t *sub_statement = intern_parse_statement();
10739                 if (is_invalid_statement(sub_statement)) {
10740                         /* an error occurred. if we are at an anchor, return */
10741                         if (at_anchor())
10742                                 goto end_error;
10743                         continue;
10744                 }
10745
10746                 if (warning.declaration_after_statement) {
10747                         if (sub_statement->kind != STATEMENT_DECLARATION) {
10748                                 only_decls_so_far = false;
10749                         } else if (!only_decls_so_far) {
10750                                 warningf(&sub_statement->base.source_position,
10751                                          "ISO C90 forbids mixed declarations and code");
10752                         }
10753                 }
10754
10755                 *anchor = sub_statement;
10756
10757                 while (sub_statement->base.next != NULL)
10758                         sub_statement = sub_statement->base.next;
10759
10760                 anchor = &sub_statement->base.next;
10761         }
10762         next_token();
10763
10764         /* look over all statements again to produce no effect warnings */
10765         if (warning.unused_value) {
10766                 statement_t *sub_statement = statement->compound.statements;
10767                 for (; sub_statement != NULL; sub_statement = sub_statement->base.next) {
10768                         if (sub_statement->kind != STATEMENT_EXPRESSION)
10769                                 continue;
10770                         /* don't emit a warning for the last expression in an expression
10771                          * statement as it has always an effect */
10772                         if (inside_expression_statement && sub_statement->base.next == NULL)
10773                                 continue;
10774
10775                         expression_t *expression = sub_statement->expression.expression;
10776                         if (!expression_has_effect(expression)) {
10777                                 warningf(&expression->base.source_position,
10778                                          "statement has no effect");
10779                         }
10780                 }
10781         }
10782
10783 end_error:
10784         rem_anchor_token('}');
10785         assert(current_scope == &statement->compound.scope);
10786         scope_pop(old_scope);
10787         environment_pop_to(top);
10788
10789         POP_PARENT;
10790         return statement;
10791 }
10792
10793 /**
10794  * Check for unused global static functions and variables
10795  */
10796 static void check_unused_globals(void)
10797 {
10798         if (!warning.unused_function && !warning.unused_variable)
10799                 return;
10800
10801         for (const entity_t *entity = file_scope->entities; entity != NULL;
10802              entity = entity->base.next) {
10803                 if (!is_declaration(entity))
10804                         continue;
10805
10806                 const declaration_t *declaration = &entity->declaration;
10807                 if (declaration->used                  ||
10808                     declaration->modifiers & DM_UNUSED ||
10809                     declaration->modifiers & DM_USED   ||
10810                     declaration->storage_class != STORAGE_CLASS_STATIC)
10811                         continue;
10812
10813                 type_t *const type = declaration->type;
10814                 const char *s;
10815                 if (entity->kind == ENTITY_FUNCTION) {
10816                         /* inhibit warning for static inline functions */
10817                         if (entity->function.is_inline)
10818                                 continue;
10819
10820                         s = entity->function.statement != NULL ? "defined" : "declared";
10821                 } else {
10822                         s = "defined";
10823                 }
10824
10825                 warningf(&declaration->base.source_position, "'%#T' %s but not used",
10826                         type, declaration->base.symbol, s);
10827         }
10828 }
10829
10830 static void parse_global_asm(void)
10831 {
10832         statement_t *statement = allocate_statement_zero(STATEMENT_ASM);
10833
10834         eat(T_asm);
10835         expect('(');
10836
10837         statement->asms.asm_text = parse_string_literals();
10838         statement->base.next     = unit->global_asm;
10839         unit->global_asm         = statement;
10840
10841         expect(')');
10842         expect(';');
10843
10844 end_error:;
10845 }
10846
10847 static void parse_linkage_specification(void)
10848 {
10849         eat(T_extern);
10850         assert(token.type == T_STRING_LITERAL);
10851
10852         const char *linkage = parse_string_literals().begin;
10853
10854         linkage_kind_t old_linkage = current_linkage;
10855         linkage_kind_t new_linkage;
10856         if (strcmp(linkage, "C") == 0) {
10857                 new_linkage = LINKAGE_C;
10858         } else if (strcmp(linkage, "C++") == 0) {
10859                 new_linkage = LINKAGE_CXX;
10860         } else {
10861                 errorf(HERE, "linkage string \"%s\" not recognized", linkage);
10862                 new_linkage = LINKAGE_INVALID;
10863         }
10864         current_linkage = new_linkage;
10865
10866         if (token.type == '{') {
10867                 next_token();
10868                 parse_externals();
10869                 expect('}');
10870         } else {
10871                 parse_external();
10872         }
10873
10874 end_error:
10875         assert(current_linkage == new_linkage);
10876         current_linkage = old_linkage;
10877 }
10878
10879 static void parse_external(void)
10880 {
10881         switch (token.type) {
10882                 DECLARATION_START_NO_EXTERN
10883                 case T_IDENTIFIER:
10884                 case T___extension__:
10885                 /* tokens below are for implicit int */
10886                 case '&': /* & x; -> int& x; (and error later, because C++ has no
10887                              implicit int) */
10888                 case '*': /* * x; -> int* x; */
10889                 case '(': /* (x); -> int (x); */
10890                         parse_external_declaration();
10891                         return;
10892
10893                 case T_extern:
10894                         if (look_ahead(1)->type == T_STRING_LITERAL) {
10895                                 parse_linkage_specification();
10896                         } else {
10897                                 parse_external_declaration();
10898                         }
10899                         return;
10900
10901                 case T_asm:
10902                         parse_global_asm();
10903                         return;
10904
10905                 case T_namespace:
10906                         parse_namespace_definition();
10907                         return;
10908
10909                 case ';':
10910                         if (!strict_mode) {
10911                                 if (warning.other)
10912                                         warningf(HERE, "stray ';' outside of function");
10913                                 next_token();
10914                                 return;
10915                         }
10916                         /* FALLTHROUGH */
10917
10918                 default:
10919                         errorf(HERE, "stray %K outside of function", &token);
10920                         if (token.type == '(' || token.type == '{' || token.type == '[')
10921                                 eat_until_matching_token(token.type);
10922                         next_token();
10923                         return;
10924         }
10925 }
10926
10927 static void parse_externals(void)
10928 {
10929         add_anchor_token('}');
10930         add_anchor_token(T_EOF);
10931
10932 #ifndef NDEBUG
10933         unsigned char token_anchor_copy[T_LAST_TOKEN];
10934         memcpy(token_anchor_copy, token_anchor_set, sizeof(token_anchor_copy));
10935 #endif
10936
10937         while (token.type != T_EOF && token.type != '}') {
10938 #ifndef NDEBUG
10939                 bool anchor_leak = false;
10940                 for (int i = 0; i != T_LAST_TOKEN; ++i) {
10941                         unsigned char count = token_anchor_set[i] - token_anchor_copy[i];
10942                         if (count != 0) {
10943                                 errorf(HERE, "Leaked anchor token %k %d times", i, count);
10944                                 anchor_leak = true;
10945                         }
10946                 }
10947                 if (in_gcc_extension) {
10948                         errorf(HERE, "Leaked __extension__");
10949                         anchor_leak = true;
10950                 }
10951
10952                 if (anchor_leak)
10953                         abort();
10954 #endif
10955
10956                 parse_external();
10957         }
10958
10959         rem_anchor_token(T_EOF);
10960         rem_anchor_token('}');
10961 }
10962
10963 /**
10964  * Parse a translation unit.
10965  */
10966 static void parse_translation_unit(void)
10967 {
10968         add_anchor_token(T_EOF);
10969
10970         while (true) {
10971                 parse_externals();
10972
10973                 if (token.type == T_EOF)
10974                         break;
10975
10976                 errorf(HERE, "stray %K outside of function", &token);
10977                 if (token.type == '(' || token.type == '{' || token.type == '[')
10978                         eat_until_matching_token(token.type);
10979                 next_token();
10980         }
10981 }
10982
10983 /**
10984  * Parse the input.
10985  *
10986  * @return  the translation unit or NULL if errors occurred.
10987  */
10988 void start_parsing(void)
10989 {
10990         environment_stack = NEW_ARR_F(stack_entry_t, 0);
10991         label_stack       = NEW_ARR_F(stack_entry_t, 0);
10992         diagnostic_count  = 0;
10993         error_count       = 0;
10994         warning_count     = 0;
10995
10996         type_set_output(stderr);
10997         ast_set_output(stderr);
10998
10999         assert(unit == NULL);
11000         unit = allocate_ast_zero(sizeof(unit[0]));
11001
11002         assert(file_scope == NULL);
11003         file_scope = &unit->scope;
11004
11005         assert(current_scope == NULL);
11006         scope_push(&unit->scope);
11007 }
11008
11009 translation_unit_t *finish_parsing(void)
11010 {
11011         assert(current_scope == &unit->scope);
11012         scope_pop(NULL);
11013
11014         assert(file_scope == &unit->scope);
11015         check_unused_globals();
11016         file_scope = NULL;
11017
11018         DEL_ARR_F(environment_stack);
11019         DEL_ARR_F(label_stack);
11020
11021         translation_unit_t *result = unit;
11022         unit = NULL;
11023         return result;
11024 }
11025
11026 /* GCC allows global arrays without size and assigns them a length of one,
11027  * if no different declaration follows */
11028 static void complete_incomplete_arrays(void)
11029 {
11030         size_t n = ARR_LEN(incomplete_arrays);
11031         for (size_t i = 0; i != n; ++i) {
11032                 declaration_t *const decl      = incomplete_arrays[i];
11033                 type_t        *const orig_type = decl->type;
11034                 type_t        *const type      = skip_typeref(orig_type);
11035
11036                 if (!is_type_incomplete(type))
11037                         continue;
11038
11039                 if (warning.other) {
11040                         warningf(&decl->base.source_position,
11041                                         "array '%#T' assumed to have one element",
11042                                         orig_type, decl->base.symbol);
11043                 }
11044
11045                 type_t *const new_type = duplicate_type(type);
11046                 new_type->array.size_constant     = true;
11047                 new_type->array.has_implicit_size = true;
11048                 new_type->array.size              = 1;
11049
11050                 type_t *const result = typehash_insert(new_type);
11051                 if (type != result)
11052                         free_type(type);
11053
11054                 decl->type = result;
11055         }
11056 }
11057
11058 void parse(void)
11059 {
11060         lookahead_bufpos = 0;
11061         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
11062                 next_token();
11063         }
11064         current_linkage   = c_mode & _CXX ? LINKAGE_CXX : LINKAGE_C;
11065         incomplete_arrays = NEW_ARR_F(declaration_t*, 0);
11066         parse_translation_unit();
11067         complete_incomplete_arrays();
11068         DEL_ARR_F(incomplete_arrays);
11069         incomplete_arrays = NULL;
11070 }
11071
11072 /**
11073  * Initialize the parser.
11074  */
11075 void init_parser(void)
11076 {
11077         sym_anonymous = symbol_table_insert("<anonymous>");
11078
11079         if (c_mode & _MS) {
11080                 /* add predefined symbols for extended-decl-modifier */
11081                 sym_align      = symbol_table_insert("align");
11082                 sym_allocate   = symbol_table_insert("allocate");
11083                 sym_dllimport  = symbol_table_insert("dllimport");
11084                 sym_dllexport  = symbol_table_insert("dllexport");
11085                 sym_naked      = symbol_table_insert("naked");
11086                 sym_noinline   = symbol_table_insert("noinline");
11087                 sym_noreturn   = symbol_table_insert("noreturn");
11088                 sym_nothrow    = symbol_table_insert("nothrow");
11089                 sym_novtable   = symbol_table_insert("novtable");
11090                 sym_property   = symbol_table_insert("property");
11091                 sym_get        = symbol_table_insert("get");
11092                 sym_put        = symbol_table_insert("put");
11093                 sym_selectany  = symbol_table_insert("selectany");
11094                 sym_thread     = symbol_table_insert("thread");
11095                 sym_uuid       = symbol_table_insert("uuid");
11096                 sym_deprecated = symbol_table_insert("deprecated");
11097                 sym_restrict   = symbol_table_insert("restrict");
11098                 sym_noalias    = symbol_table_insert("noalias");
11099         }
11100         memset(token_anchor_set, 0, sizeof(token_anchor_set));
11101
11102         init_expression_parsers();
11103         obstack_init(&temp_obst);
11104
11105         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
11106         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
11107 }
11108
11109 /**
11110  * Terminate the parser.
11111  */
11112 void exit_parser(void)
11113 {
11114         obstack_free(&temp_obst, NULL);
11115 }