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                 has_arguments; /**< True, if this attribute has arguments. */
  65         union {
  66                 size_t              value;
  67                 string_t            string;
  68                 atomic_type_kind_t  akind;
  69                 long                argument;  /**< Single argument. */
  70                 argument_list_t    *arguments; /**< List of argument expressions. */
  71         } u;
  72 };
  73
  74 typedef struct declaration_specifiers_t  declaration_specifiers_t;
  75 struct declaration_specifiers_t {
  76         source_position_t  source_position;
  77         storage_class_t    storage_class;
  78         unsigned char      alignment;         /**< Alignment, 0 if not set. */
  79         bool               is_inline    : 1;
  80         bool               thread_local : 1;  /**< GCC __thread */
  81         bool               deprecated   : 1;
  82         decl_modifiers_t   modifiers;         /**< declaration modifiers */
  83         gnu_attribute_t   *gnu_attributes;    /**< list of GNU attributes */
  84         const char        *deprecated_string; /**< can be set if declaration was marked deprecated. */
  85         symbol_t          *get_property_sym;  /**< the name of the get property if set. */
  86         symbol_t          *put_property_sym;  /**< the name of the put property if set. */
  87         type_t            *type;
  88 };
  89
  90 /**
  91  * An environment for parsing initializers (and compound literals).
  92  */
  93 typedef struct parse_initializer_env_t {
  94         type_t     *type;   /**< the type of the initializer. In case of an
  95                                  array type with unspecified size this gets
  96                                  adjusted to the actual size. */
  97         entity_t   *entity; /**< the variable that is initialized if any */
  98         bool        must_be_constant;
  99 } parse_initializer_env_t;
 100
 101 /**
 102  * Capture a MS __base extension.
 103  */
 104 typedef struct based_spec_t {
 105         source_position_t  source_position;
 106         variable_t        *base_variable;
 107 } based_spec_t;
 108
 109 typedef entity_t* (*parsed_declaration_func) (entity_t *declaration, bool is_definition);
 110
 111 /** The current token. */
 112 static token_t              token;
 113 /** The lookahead ring-buffer. */
 114 static token_t              lookahead_buffer[MAX_LOOKAHEAD];
 115 /** Position of the next token in the lookahead buffer. */
 116 static int                  lookahead_bufpos;
 117 static stack_entry_t       *environment_stack = NULL;
 118 static stack_entry_t       *label_stack       = NULL;
 119 static scope_t             *file_scope        = NULL;
 120 static scope_t             *current_scope     = NULL;
 121 /** Point to the current function declaration if inside a function. */
 122 static function_t          *current_function  = NULL;
 123 static entity_t            *current_init_decl = NULL;
 124 static switch_statement_t  *current_switch    = NULL;
 125 static statement_t         *current_loop      = NULL;
 126 static statement_t         *current_parent    = NULL;
 127 static ms_try_statement_t  *current_try       = NULL;
 128 static linkage_kind_t       current_linkage   = LINKAGE_INVALID;
 129 static goto_statement_t    *goto_first        = NULL;
 130 static goto_statement_t   **goto_anchor       = NULL;
 131 static label_statement_t   *label_first       = NULL;
 132 static label_statement_t  **label_anchor      = NULL;
 133 /** current translation unit. */
 134 static translation_unit_t  *unit              = NULL;
 135 /** true if we are in a type property context (evaluation only for type. */
 136 static bool                 in_type_prop      = false;
 137 /** true in we are in a __extension__ context. */
 138 static bool                 in_gcc_extension  = false;
 139 static struct obstack       temp_obst;
 140 static entity_t            *anonymous_entity;
 141 static declaration_t      **incomplete_arrays;
 142
 143
 144 #define PUSH_PARENT(stmt)                          \
 145         statement_t *const prev_parent = current_parent; \
 146         ((void)(current_parent = (stmt)))
 147 #define POP_PARENT ((void)(current_parent = prev_parent))
 148
 149 /** special symbol used for anonymous entities. */
 150 static const symbol_t *sym_anonymous = NULL;
 151
 152 /* symbols for Microsoft extended-decl-modifier */
 153 static const symbol_t *sym_align         = NULL;
 154 static const symbol_t *sym_allocate      = NULL;
 155 static const symbol_t *sym_dllimport     = NULL;
 156 static const symbol_t *sym_dllexport     = NULL;
 157 static const symbol_t *sym_naked         = NULL;
 158 static const symbol_t *sym_noinline      = NULL;
 159 static const symbol_t *sym_returns_twice = NULL;
 160 static const symbol_t *sym_noreturn      = NULL;
 161 static const symbol_t *sym_nothrow       = NULL;
 162 static const symbol_t *sym_novtable      = NULL;
 163 static const symbol_t *sym_property      = NULL;
 164 static const symbol_t *sym_get           = NULL;
 165 static const symbol_t *sym_put           = NULL;
 166 static const symbol_t *sym_selectany     = NULL;
 167 static const symbol_t *sym_thread        = NULL;
 168 static const symbol_t *sym_uuid          = NULL;
 169 static const symbol_t *sym_deprecated    = NULL;
 170 static const symbol_t *sym_restrict      = NULL;
 171 static const symbol_t *sym_noalias       = NULL;
 172
 173 /** The token anchor set */
 174 static unsigned char token_anchor_set[T_LAST_TOKEN];
 175
 176 /** The current source position. */
 177 #define HERE (&token.source_position)
 178
 179 /** true if we are in GCC mode. */
 180 #define GNU_MODE ((c_mode & _GNUC) || in_gcc_extension)
 181
 182 static type_t *type_valist;
 183
 184 static statement_t *parse_compound_statement(bool inside_expression_statement);
 185 static statement_t *parse_statement(void);
 186
 187 static expression_t *parse_sub_expression(precedence_t);
 188 static expression_t *parse_expression(void);
 189 static type_t       *parse_typename(void);
 190 static void          parse_externals(void);
 191 static void          parse_external(void);
 192
 193 static void parse_compound_type_entries(compound_t *compound_declaration);
 194
 195 typedef enum declarator_flags_t {
 196         DECL_FLAGS_NONE             = 0,
 197         DECL_MAY_BE_ABSTRACT        = 1U << 0,
 198         DECL_CREATE_COMPOUND_MEMBER = 1U << 1,
 199         DECL_IS_PARAMETER           = 1U << 2
 200 } declarator_flags_t;
 201
 202 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
 203                                   declarator_flags_t flags);
 204
 205 static entity_t *record_entity(entity_t *entity, bool is_definition);
 206
 207 static void semantic_comparison(binary_expression_t *expression);
 208
 209 #define STORAGE_CLASSES       \
 210         STORAGE_CLASSES_NO_EXTERN \
 211         case T_extern:
 212
 213 #define STORAGE_CLASSES_NO_EXTERN \
 214         case T_typedef:         \
 215         case T_static:          \
 216         case T_auto:            \
 217         case T_register:        \
 218         case T___thread:
 219
 220 #define TYPE_QUALIFIERS     \
 221         case T_const:           \
 222         case T_restrict:        \
 223         case T_volatile:        \
 224         case T_inline:          \
 225         case T__forceinline:    \
 226         case T___attribute__:
 227
 228 #define COMPLEX_SPECIFIERS  \
 229         case T__Complex:
 230 #define IMAGINARY_SPECIFIERS \
 231         case T__Imaginary:
 232
 233 #define TYPE_SPECIFIERS       \
 234         case T__Bool:             \
 235         case T___builtin_va_list: \
 236         case T___typeof__:        \
 237         case T__declspec:         \
 238         case T_bool:              \
 239         case T_char:              \
 240         case T_double:            \
 241         case T_enum:              \
 242         case T_float:             \
 243         case T_int:               \
 244         case T_long:              \
 245         case T_short:             \
 246         case T_signed:            \
 247         case T_struct:            \
 248         case T_union:             \
 249         case T_unsigned:          \
 250         case T_void:              \
 251         case T_wchar_t:           \
 252         COMPLEX_SPECIFIERS        \
 253         IMAGINARY_SPECIFIERS
 254
 255 #define DECLARATION_START   \
 256         STORAGE_CLASSES         \
 257         TYPE_QUALIFIERS         \
 258         TYPE_SPECIFIERS
 259
 260 #define DECLARATION_START_NO_EXTERN \
 261         STORAGE_CLASSES_NO_EXTERN       \
 262         TYPE_QUALIFIERS                 \
 263         TYPE_SPECIFIERS
 264
 265 #define TYPENAME_START      \
 266         TYPE_QUALIFIERS         \
 267         TYPE_SPECIFIERS
 268
 269 #define EXPRESSION_START           \
 270         case '!':                        \
 271         case '&':                        \
 272         case '(':                        \
 273         case '*':                        \
 274         case '+':                        \
 275         case '-':                        \
 276         case '~':                        \
 277         case T_ANDAND:                   \
 278         case T_CHARACTER_CONSTANT:       \
 279         case T_FLOATINGPOINT:            \
 280         case T_INTEGER:                  \
 281         case T_MINUSMINUS:               \
 282         case T_PLUSPLUS:                 \
 283         case T_STRING_LITERAL:           \
 284         case T_WIDE_CHARACTER_CONSTANT:  \
 285         case T_WIDE_STRING_LITERAL:      \
 286         case T___FUNCDNAME__:            \
 287         case T___FUNCSIG__:              \
 288         case T___FUNCTION__:             \
 289         case T___PRETTY_FUNCTION__:      \
 290         case T___alignof__:              \
 291         case T___builtin_alloca:         \
 292         case T___builtin_classify_type:  \
 293         case T___builtin_constant_p:     \
 294         case T___builtin_expect:         \
 295         case T___builtin_huge_val:       \
 296         case T___builtin_inf:            \
 297         case T___builtin_inff:           \
 298         case T___builtin_infl:           \
 299         case T___builtin_isgreater:      \
 300         case T___builtin_isgreaterequal: \
 301         case T___builtin_isless:         \
 302         case T___builtin_islessequal:    \
 303         case T___builtin_islessgreater:  \
 304         case T___builtin_isunordered:    \
 305         case T___builtin_nan:            \
 306         case T___builtin_nanf:           \
 307         case T___builtin_nanl:           \
 308         case T___builtin_offsetof:       \
 309         case T___builtin_prefetch:       \
 310         case T___builtin_va_arg:         \
 311         case T___builtin_va_end:         \
 312         case T___builtin_va_start:       \
 313         case T___func__:                 \
 314         case T___noop:                   \
 315         case T__assume:                  \
 316         case T_delete:                   \
 317         case T_false:                    \
 318         case T_sizeof:                   \
 319         case T_throw:                    \
 320         case T_true:
 321
 322 /**
 323  * Allocate an AST node with given size and
 324  * initialize all fields with zero.
 325  */
 326 static void *allocate_ast_zero(size_t size)
 327 {
 328         void *res = allocate_ast(size);
 329         memset(res, 0, size);
 330         return res;
 331 }
 332
 333 /**
 334  * Returns the size of an entity node.
 335  *
 336  * @param kind  the entity kind
 337  */
 338 static size_t get_entity_struct_size(entity_kind_t kind)
 339 {
 340         static const size_t sizes[] = {
 341                 [ENTITY_VARIABLE]        = sizeof(variable_t),
 342                 [ENTITY_PARAMETER]       = sizeof(parameter_t),
 343                 [ENTITY_COMPOUND_MEMBER] = sizeof(compound_member_t),
 344                 [ENTITY_FUNCTION]        = sizeof(function_t),
 345                 [ENTITY_TYPEDEF]         = sizeof(typedef_t),
 346                 [ENTITY_STRUCT]          = sizeof(compound_t),
 347                 [ENTITY_UNION]           = sizeof(compound_t),
 348                 [ENTITY_ENUM]            = sizeof(enum_t),
 349                 [ENTITY_ENUM_VALUE]      = sizeof(enum_value_t),
 350                 [ENTITY_LABEL]           = sizeof(label_t),
 351                 [ENTITY_LOCAL_LABEL]     = sizeof(label_t),
 352                 [ENTITY_NAMESPACE]       = sizeof(namespace_t)
 353         };
 354         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 355         assert(sizes[kind] != 0);
 356         return sizes[kind];
 357 }
 358
 359 /**
 360  * Allocate an entity of given kind and initialize all
 361  * fields with zero.
 362  */
 363 static entity_t *allocate_entity_zero(entity_kind_t kind)
 364 {
 365         size_t    size   = get_entity_struct_size(kind);
 366         entity_t *entity = allocate_ast_zero(size);
 367         entity->kind     = kind;
 368         return entity;
 369 }
 370
 371 /**
 372  * Returns the size of a statement node.
 373  *
 374  * @param kind  the statement kind
 375  */
 376 static size_t get_statement_struct_size(statement_kind_t kind)
 377 {
 378         static const size_t sizes[] = {
 379                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 380                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 381                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 382                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 383                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 384                 [STATEMENT_IF]          = sizeof(if_statement_t),
 385                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 386                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 387                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 388                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 389                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 390                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 391                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 392                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 393                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 394                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 395                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 396                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 397                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 398         };
 399         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 400         assert(sizes[kind] != 0);
 401         return sizes[kind];
 402 }
 403
 404 /**
 405  * Returns the size of an expression node.
 406  *
 407  * @param kind  the expression kind
 408  */
 409 static size_t get_expression_struct_size(expression_kind_t kind)
 410 {
 411         static const size_t sizes[] = {
 412                 [EXPR_INVALID]                 = sizeof(expression_base_t),
 413                 [EXPR_REFERENCE]               = sizeof(reference_expression_t),
 414                 [EXPR_REFERENCE_ENUM_VALUE]    = sizeof(reference_expression_t),
 415                 [EXPR_CONST]                   = sizeof(const_expression_t),
 416                 [EXPR_CHARACTER_CONSTANT]      = sizeof(const_expression_t),
 417                 [EXPR_WIDE_CHARACTER_CONSTANT] = sizeof(const_expression_t),
 418                 [EXPR_STRING_LITERAL]          = sizeof(string_literal_expression_t),
 419                 [EXPR_WIDE_STRING_LITERAL]     = sizeof(wide_string_literal_expression_t),
 420                 [EXPR_COMPOUND_LITERAL]        = sizeof(compound_literal_expression_t),
 421                 [EXPR_CALL]                    = sizeof(call_expression_t),
 422                 [EXPR_UNARY_FIRST]             = sizeof(unary_expression_t),
 423                 [EXPR_BINARY_FIRST]            = sizeof(binary_expression_t),
 424                 [EXPR_CONDITIONAL]             = sizeof(conditional_expression_t),
 425                 [EXPR_SELECT]                  = sizeof(select_expression_t),
 426                 [EXPR_ARRAY_ACCESS]            = sizeof(array_access_expression_t),
 427                 [EXPR_SIZEOF]                  = sizeof(typeprop_expression_t),
 428                 [EXPR_ALIGNOF]                 = sizeof(typeprop_expression_t),
 429                 [EXPR_CLASSIFY_TYPE]           = sizeof(classify_type_expression_t),
 430                 [EXPR_FUNCNAME]                = sizeof(funcname_expression_t),
 431                 [EXPR_BUILTIN_SYMBOL]          = sizeof(builtin_symbol_expression_t),
 432                 [EXPR_BUILTIN_CONSTANT_P]      = sizeof(builtin_constant_expression_t),
 433                 [EXPR_BUILTIN_PREFETCH]        = sizeof(builtin_prefetch_expression_t),
 434                 [EXPR_OFFSETOF]                = sizeof(offsetof_expression_t),
 435                 [EXPR_VA_START]                = sizeof(va_start_expression_t),
 436                 [EXPR_VA_ARG]                  = sizeof(va_arg_expression_t),
 437                 [EXPR_STATEMENT]               = sizeof(statement_expression_t),
 438                 [EXPR_LABEL_ADDRESS]           = sizeof(label_address_expression_t),
 439         };
 440         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 441                 return sizes[EXPR_UNARY_FIRST];
 442         }
 443         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 444                 return sizes[EXPR_BINARY_FIRST];
 445         }
 446         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 447         assert(sizes[kind] != 0);
 448         return sizes[kind];
 449 }
 450
 451 /**
 452  * Allocate a statement node of given kind and initialize all
 453  * fields with zero. Sets its source position to the position
 454  * of the current token.
 455  */
 456 static statement_t *allocate_statement_zero(statement_kind_t kind)
 457 {
 458         size_t       size = get_statement_struct_size(kind);
 459         statement_t *res  = allocate_ast_zero(size);
 460
 461         res->base.kind            = kind;
 462         res->base.parent          = current_parent;
 463         res->base.source_position = token.source_position;
 464         return res;
 465 }
 466
 467 /**
 468  * Allocate an expression node of given kind and initialize all
 469  * fields with zero.
 470  */
 471 static expression_t *allocate_expression_zero(expression_kind_t kind)
 472 {
 473         size_t        size = get_expression_struct_size(kind);
 474         expression_t *res  = allocate_ast_zero(size);
 475
 476         res->base.kind            = kind;
 477         res->base.type            = type_error_type;
 478         res->base.source_position = token.source_position;
 479         return res;
 480 }
 481
 482 /**
 483  * Creates a new invalid expression at the source position
 484  * of the current token.
 485  */
 486 static expression_t *create_invalid_expression(void)
 487 {
 488         return allocate_expression_zero(EXPR_INVALID);
 489 }
 490
 491 /**
 492  * Creates a new invalid statement.
 493  */
 494 static statement_t *create_invalid_statement(void)
 495 {
 496         return allocate_statement_zero(STATEMENT_INVALID);
 497 }
 498
 499 /**
 500  * Allocate a new empty statement.
 501  */
 502 static statement_t *create_empty_statement(void)
 503 {
 504         return allocate_statement_zero(STATEMENT_EMPTY);
 505 }
 506
 507 /**
 508  * Returns the size of a type node.
 509  *
 510  * @param kind  the type kind
 511  */
 512 static size_t get_type_struct_size(type_kind_t kind)
 513 {
 514         static const size_t sizes[] = {
 515                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
 516                 [TYPE_COMPLEX]         = sizeof(complex_type_t),
 517                 [TYPE_IMAGINARY]       = sizeof(imaginary_type_t),
 518                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
 519                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
 520                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
 521                 [TYPE_ENUM]            = sizeof(enum_type_t),
 522                 [TYPE_FUNCTION]        = sizeof(function_type_t),
 523                 [TYPE_POINTER]         = sizeof(pointer_type_t),
 524                 [TYPE_ARRAY]           = sizeof(array_type_t),
 525                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
 526                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
 527                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
 528         };
 529         assert(sizeof(sizes) / sizeof(sizes[0]) == (int) TYPE_TYPEOF + 1);
 530         assert(kind <= TYPE_TYPEOF);
 531         assert(sizes[kind] != 0);
 532         return sizes[kind];
 533 }
 534
 535 /**
 536  * Allocate a type node of given kind and initialize all
 537  * fields with zero.
 538  *
 539  * @param kind             type kind to allocate
 540  */
 541 static type_t *allocate_type_zero(type_kind_t kind)
 542 {
 543         size_t  size = get_type_struct_size(kind);
 544         type_t *res  = obstack_alloc(type_obst, size);
 545         memset(res, 0, size);
 546         res->base.kind = kind;
 547
 548         return res;
 549 }
 550
 551 /**
 552  * Returns the size of an initializer node.
 553  *
 554  * @param kind  the initializer kind
 555  */
 556 static size_t get_initializer_size(initializer_kind_t kind)
 557 {
 558         static const size_t sizes[] = {
 559                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 560                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 561                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 562                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 563                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 564         };
 565         assert(kind < sizeof(sizes) / sizeof(*sizes));
 566         assert(sizes[kind] != 0);
 567         return sizes[kind];
 568 }
 569
 570 /**
 571  * Allocate an initializer node of given kind and initialize all
 572  * fields with zero.
 573  */
 574 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 575 {
 576         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 577         result->kind          = kind;
 578
 579         return result;
 580 }
 581
 582 /**
 583  * Returns the index of the top element of the environment stack.
 584  */
 585 static size_t environment_top(void)
 586 {
 587         return ARR_LEN(environment_stack);
 588 }
 589
 590 /**
 591  * Returns the index of the top element of the global label stack.
 592  */
 593 static size_t label_top(void)
 594 {
 595         return ARR_LEN(label_stack);
 596 }
 597
 598 /**
 599  * Return the next token.
 600  */
 601 static inline void next_token(void)
 602 {
 603         token                              = lookahead_buffer[lookahead_bufpos];
 604         lookahead_buffer[lookahead_bufpos] = lexer_token;
 605         lexer_next_token();
 606
 607         lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
 608
 609 #ifdef PRINT_TOKENS
 610         print_token(stderr, &token);
 611         fprintf(stderr, "\n");
 612 #endif
 613 }
 614
 615 /**
 616  * Return the next token with a given lookahead.
 617  */
 618 static inline const token_t *look_ahead(int num)
 619 {
 620         assert(num > 0 && num <= MAX_LOOKAHEAD);
 621         int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
 622         return &lookahead_buffer[pos];
 623 }
 624
 625 /**
 626  * Adds a token type to the token type anchor set (a multi-set).
 627  */
 628 static void add_anchor_token(int token_type)
 629 {
 630         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 631         ++token_anchor_set[token_type];
 632 }
 633
 634 /**
 635  * Set the number of tokens types of the given type
 636  * to zero and return the old count.
 637  */
 638 static int save_and_reset_anchor_state(int token_type)
 639 {
 640         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 641         int count = token_anchor_set[token_type];
 642         token_anchor_set[token_type] = 0;
 643         return count;
 644 }
 645
 646 /**
 647  * Restore the number of token types to the given count.
 648  */
 649 static void restore_anchor_state(int token_type, int count)
 650 {
 651         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 652         token_anchor_set[token_type] = count;
 653 }
 654
 655 /**
 656  * Remove a token type from the token type anchor set (a multi-set).
 657  */
 658 static void rem_anchor_token(int token_type)
 659 {
 660         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 661         assert(token_anchor_set[token_type] != 0);
 662         --token_anchor_set[token_type];
 663 }
 664
 665 /**
 666  * Return true if the token type of the current token is
 667  * in the anchor set.
 668  */
 669 static bool at_anchor(void)
 670 {
 671         if (token.type < 0)
 672                 return false;
 673         return token_anchor_set[token.type];
 674 }
 675
 676 /**
 677  * Eat tokens until a matching token type is found.
 678  */
 679 static void eat_until_matching_token(int type)
 680 {
 681         int end_token;
 682         switch (type) {
 683                 case '(': end_token = ')';  break;
 684                 case '{': end_token = '}';  break;
 685                 case '[': end_token = ']';  break;
 686                 default:  end_token = type; break;
 687         }
 688
 689         unsigned parenthesis_count = 0;
 690         unsigned brace_count       = 0;
 691         unsigned bracket_count     = 0;
 692         while (token.type        != end_token ||
 693                parenthesis_count != 0         ||
 694                brace_count       != 0         ||
 695                bracket_count     != 0) {
 696                 switch (token.type) {
 697                 case T_EOF: return;
 698                 case '(': ++parenthesis_count; break;
 699                 case '{': ++brace_count;       break;
 700                 case '[': ++bracket_count;     break;
 701
 702                 case ')':
 703                         if (parenthesis_count > 0)
 704                                 --parenthesis_count;
 705                         goto check_stop;
 706
 707                 case '}':
 708                         if (brace_count > 0)
 709                                 --brace_count;
 710                         goto check_stop;
 711
 712                 case ']':
 713                         if (bracket_count > 0)
 714                                 --bracket_count;
 715 check_stop:
 716                         if (token.type        == end_token &&
 717                             parenthesis_count == 0         &&
 718                             brace_count       == 0         &&
 719                             bracket_count     == 0)
 720                                 return;
 721                         break;
 722
 723                 default:
 724                         break;
 725                 }
 726                 next_token();
 727         }
 728 }
 729
 730 /**
 731  * Eat input tokens until an anchor is found.
 732  */
 733 static void eat_until_anchor(void)
 734 {
 735         while (token_anchor_set[token.type] == 0) {
 736                 if (token.type == '(' || token.type == '{' || token.type == '[')
 737                         eat_until_matching_token(token.type);
 738                 next_token();
 739         }
 740 }
 741
 742 /**
 743  * Eat a whole block from input tokens.
 744  */
 745 static void eat_block(void)
 746 {
 747         eat_until_matching_token('{');
 748         if (token.type == '}')
 749                 next_token();
 750 }
 751
 752 #define eat(token_type) (assert(token.type == (token_type)), next_token())
 753
 754 /**
 755  * Report a parse error because an expected token was not found.
 756  */
 757 static
 758 #if defined __GNUC__ && __GNUC__ >= 4
 759 __attribute__((sentinel))
 760 #endif
 761 void parse_error_expected(const char *message, ...)
 762 {
 763         if (message != NULL) {
 764                 errorf(HERE, "%s", message);
 765         }
 766         va_list ap;
 767         va_start(ap, message);
 768         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 769         va_end(ap);
 770 }
 771
 772 /**
 773  * Report an incompatible type.
 774  */
 775 static void type_error_incompatible(const char *msg,
 776                 const source_position_t *source_position, type_t *type1, type_t *type2)
 777 {
 778         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 779                msg, type1, type2);
 780 }
 781
 782 /**
 783  * Expect the current token is the expected token.
 784  * If not, generate an error, eat the current statement,
 785  * and goto the end_error label.
 786  */
 787 #define expect(expected, error_label)                     \
 788         do {                                                  \
 789                 if (UNLIKELY(token.type != (expected))) {         \
 790                         parse_error_expected(NULL, (expected), NULL); \
 791                         add_anchor_token(expected);                   \
 792                         eat_until_anchor();                           \
 793                         if (token.type == expected)                   \
 794                                 next_token();                             \
 795                         rem_anchor_token(expected);                   \
 796                         goto error_label;                             \
 797                 }                                                 \
 798                 next_token();                                     \
 799         } while (0)
 800
 801 /**
 802  * Push a given scope on the scope stack and make it the
 803  * current scope
 804  */
 805 static scope_t *scope_push(scope_t *new_scope)
 806 {
 807         if (current_scope != NULL) {
 808                 new_scope->depth = current_scope->depth + 1;
 809         }
 810
 811         scope_t *old_scope = current_scope;
 812         current_scope      = new_scope;
 813         return old_scope;
 814 }
 815
 816 /**
 817  * Pop the current scope from the scope stack.
 818  */
 819 static void scope_pop(scope_t *old_scope)
 820 {
 821         current_scope = old_scope;
 822 }
 823
 824 /**
 825  * Search an entity by its symbol in a given namespace.
 826  */
 827 static entity_t *get_entity(const symbol_t *const symbol,
 828                             namespace_tag_t namespc)
 829 {
 830         entity_t *entity = symbol->entity;
 831         for (; entity != NULL; entity = entity->base.symbol_next) {
 832                 if (entity->base.namespc == namespc)
 833                         return entity;
 834         }
 835
 836         return NULL;
 837 }
 838
 839 /**
 840  * pushs an entity on the environment stack and links the corresponding symbol
 841  * it.
 842  */
 843 static void stack_push(stack_entry_t **stack_ptr, entity_t *entity)
 844 {
 845         symbol_t           *symbol  = entity->base.symbol;
 846         entity_namespace_t  namespc = entity->base.namespc;
 847         assert(namespc != NAMESPACE_INVALID);
 848
 849         /* replace/add entity into entity list of the symbol */
 850         entity_t **anchor;
 851         entity_t  *iter;
 852         for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 853                 iter = *anchor;
 854                 if (iter == NULL)
 855                         break;
 856
 857                 /* replace an entry? */
 858                 if (iter->base.namespc == namespc) {
 859                         entity->base.symbol_next = iter->base.symbol_next;
 860                         break;
 861                 }
 862         }
 863         *anchor = entity;
 864
 865         /* remember old declaration */
 866         stack_entry_t entry;
 867         entry.symbol     = symbol;
 868         entry.old_entity = iter;
 869         entry.namespc    = namespc;
 870         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 871 }
 872
 873 /**
 874  * Push an entity on the environment stack.
 875  */
 876 static void environment_push(entity_t *entity)
 877 {
 878         assert(entity->base.source_position.input_name != NULL);
 879         assert(entity->base.parent_scope != NULL);
 880         stack_push(&environment_stack, entity);
 881 }
 882
 883 /**
 884  * Push a declaration on the global label stack.
 885  *
 886  * @param declaration  the declaration
 887  */
 888 static void label_push(entity_t *label)
 889 {
 890         /* we abuse the parameters scope as parent for the labels */
 891         label->base.parent_scope = &current_function->parameters;
 892         stack_push(&label_stack, label);
 893 }
 894
 895 /**
 896  * pops symbols from the environment stack until @p new_top is the top element
 897  */
 898 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 899 {
 900         stack_entry_t *stack = *stack_ptr;
 901         size_t         top   = ARR_LEN(stack);
 902         size_t         i;
 903
 904         assert(new_top <= top);
 905         if (new_top == top)
 906                 return;
 907
 908         for (i = top; i > new_top; --i) {
 909                 stack_entry_t *entry = &stack[i - 1];
 910
 911                 entity_t           *old_entity = entry->old_entity;
 912                 symbol_t           *symbol     = entry->symbol;
 913                 entity_namespace_t  namespc    = entry->namespc;
 914
 915                 /* replace with old_entity/remove */
 916                 entity_t **anchor;
 917                 entity_t  *iter;
 918                 for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 919                         iter = *anchor;
 920                         assert(iter != NULL);
 921                         /* replace an entry? */
 922                         if (iter->base.namespc == namespc)
 923                                 break;
 924                 }
 925
 926                 /* restore definition from outer scopes (if there was one) */
 927                 if (old_entity != NULL) {
 928                         old_entity->base.symbol_next = iter->base.symbol_next;
 929                         *anchor                      = old_entity;
 930                 } else {
 931                         /* remove entry from list */
 932                         *anchor = iter->base.symbol_next;
 933                 }
 934         }
 935
 936         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
 937 }
 938
 939 /**
 940  * Pop all entries from the environment stack until the new_top
 941  * is reached.
 942  *
 943  * @param new_top  the new stack top
 944  */
 945 static void environment_pop_to(size_t new_top)
 946 {
 947         stack_pop_to(&environment_stack, new_top);
 948 }
 949
 950 /**
 951  * Pop all entries from the global label stack until the new_top
 952  * is reached.
 953  *
 954  * @param new_top  the new stack top
 955  */
 956 static void label_pop_to(size_t new_top)
 957 {
 958         stack_pop_to(&label_stack, new_top);
 959 }
 960
 961 static int get_akind_rank(atomic_type_kind_t akind)
 962 {
 963         return (int) akind;
 964 }
 965
 966 /**
 967  * Return the type rank for an atomic type.
 968  */
 969 static int get_rank(const type_t *type)
 970 {
 971         assert(!is_typeref(type));
 972         /* The C-standard allows promoting enums to int or unsigned int (see § 7.2.2
 973          * and esp. footnote 108). However we can't fold constants (yet), so we
 974          * can't decide whether unsigned int is possible, while int always works.
 975          * (unsigned int would be preferable when possible... for stuff like
 976          *  struct { enum { ... } bla : 4; } ) */
 977         if (type->kind == TYPE_ENUM)
 978                 return get_akind_rank(ATOMIC_TYPE_INT);
 979
 980         assert(type->kind == TYPE_ATOMIC);
 981         return get_akind_rank(type->atomic.akind);
 982 }
 983
 984 /**
 985  * Do integer promotion for a given type.
 986  *
 987  * @param type  the type to promote
 988  * @return the promoted type
 989  */
 990 static type_t *promote_integer(type_t *type)
 991 {
 992         if (type->kind == TYPE_BITFIELD)
 993                 type = type->bitfield.base_type;
 994
 995         if (get_rank(type) < get_akind_rank(ATOMIC_TYPE_INT))
 996                 type = type_int;
 997
 998         return type;
 999 }
1000
1001 /**
1002  * Create a cast expression.
1003  *
1004  * @param expression  the expression to cast
1005  * @param dest_type   the destination type
1006  */
1007 static expression_t *create_cast_expression(expression_t *expression,
1008                                             type_t *dest_type)
1009 {
1010         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
1011
1012         cast->unary.value = expression;
1013         cast->base.type   = dest_type;
1014
1015         return cast;
1016 }
1017
1018 /**
1019  * Check if a given expression represents a null pointer constant.
1020  *
1021  * @param expression  the expression to check
1022  */
1023 static bool is_null_pointer_constant(const expression_t *expression)
1024 {
1025         /* skip void* cast */
1026         if (expression->kind == EXPR_UNARY_CAST ||
1027                         expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
1028                 type_t *const type = skip_typeref(expression->base.type);
1029                 if (types_compatible(type, type_void_ptr))
1030                         expression = expression->unary.value;
1031         }
1032
1033         type_t *const type = skip_typeref(expression->base.type);
1034         return
1035                 is_type_integer(type)              &&
1036                 is_constant_expression(expression) &&
1037                 fold_constant(expression) == 0;
1038 }
1039
1040 /**
1041  * Create an implicit cast expression.
1042  *
1043  * @param expression  the expression to cast
1044  * @param dest_type   the destination type
1045  */
1046 static expression_t *create_implicit_cast(expression_t *expression,
1047                                           type_t *dest_type)
1048 {
1049         type_t *const source_type = expression->base.type;
1050
1051         if (source_type == dest_type)
1052                 return expression;
1053
1054         return create_cast_expression(expression, dest_type);
1055 }
1056
1057 typedef enum assign_error_t {
1058         ASSIGN_SUCCESS,
1059         ASSIGN_ERROR_INCOMPATIBLE,
1060         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
1061         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
1062         ASSIGN_WARNING_POINTER_FROM_INT,
1063         ASSIGN_WARNING_INT_FROM_POINTER
1064 } assign_error_t;
1065
1066 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
1067                                 const expression_t *const right,
1068                                 const char *context,
1069                                 const source_position_t *source_position)
1070 {
1071         type_t *const orig_type_right = right->base.type;
1072         type_t *const type_left       = skip_typeref(orig_type_left);
1073         type_t *const type_right      = skip_typeref(orig_type_right);
1074
1075         switch (error) {
1076         case ASSIGN_SUCCESS:
1077                 return;
1078         case ASSIGN_ERROR_INCOMPATIBLE:
1079                 errorf(source_position,
1080                        "destination type '%T' in %s is incompatible with type '%T'",
1081                        orig_type_left, context, orig_type_right);
1082                 return;
1083
1084         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
1085                 if (warning.other) {
1086                         type_t *points_to_left  = skip_typeref(type_left->pointer.points_to);
1087                         type_t *points_to_right = skip_typeref(type_right->pointer.points_to);
1088
1089                         /* the left type has all qualifiers from the right type */
1090                         unsigned missing_qualifiers
1091                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1092                         warningf(source_position,
1093                                         "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
1094                                         orig_type_left, context, orig_type_right, missing_qualifiers);
1095                 }
1096                 return;
1097         }
1098
1099         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
1100                 if (warning.other) {
1101                         warningf(source_position,
1102                                         "destination type '%T' in %s is incompatible with '%E' of type '%T'",
1103                                         orig_type_left, context, right, orig_type_right);
1104                 }
1105                 return;
1106
1107         case ASSIGN_WARNING_POINTER_FROM_INT:
1108                 if (warning.other) {
1109                         warningf(source_position,
1110                                         "%s makes pointer '%T' from integer '%T' without a cast",
1111                                         context, orig_type_left, orig_type_right);
1112                 }
1113                 return;
1114
1115         case ASSIGN_WARNING_INT_FROM_POINTER:
1116                 if (warning.other) {
1117                         warningf(source_position,
1118                                         "%s makes integer '%T' from pointer '%T' without a cast",
1119                                         context, orig_type_left, orig_type_right);
1120                 }
1121                 return;
1122
1123         default:
1124                 panic("invalid error value");
1125         }
1126 }
1127
1128 /** Implements the rules from § 6.5.16.1 */
1129 static assign_error_t semantic_assign(type_t *orig_type_left,
1130                                       const expression_t *const right)
1131 {
1132         type_t *const orig_type_right = right->base.type;
1133         type_t *const type_left       = skip_typeref(orig_type_left);
1134         type_t *const type_right      = skip_typeref(orig_type_right);
1135
1136         if (is_type_pointer(type_left)) {
1137                 if (is_null_pointer_constant(right)) {
1138                         return ASSIGN_SUCCESS;
1139                 } else if (is_type_pointer(type_right)) {
1140                         type_t *points_to_left
1141                                 = skip_typeref(type_left->pointer.points_to);
1142                         type_t *points_to_right
1143                                 = skip_typeref(type_right->pointer.points_to);
1144                         assign_error_t res = ASSIGN_SUCCESS;
1145
1146                         /* the left type has all qualifiers from the right type */
1147                         unsigned missing_qualifiers
1148                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1149                         if (missing_qualifiers != 0) {
1150                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1151                         }
1152
1153                         points_to_left  = get_unqualified_type(points_to_left);
1154                         points_to_right = get_unqualified_type(points_to_right);
1155
1156                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID))
1157                                 return res;
1158
1159                         if (is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1160                                 /* ISO/IEC 14882:1998(E) §C.1.2:6 */
1161                                 return c_mode & _CXX ? ASSIGN_ERROR_INCOMPATIBLE : res;
1162                         }
1163
1164                         if (!types_compatible(points_to_left, points_to_right)) {
1165                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1166                         }
1167
1168                         return res;
1169                 } else if (is_type_integer(type_right)) {
1170                         return ASSIGN_WARNING_POINTER_FROM_INT;
1171                 }
1172         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1173             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1174                 && is_type_pointer(type_right))) {
1175                 return ASSIGN_SUCCESS;
1176         } else if ((is_type_compound(type_left)  && is_type_compound(type_right))
1177                         || (is_type_builtin(type_left) && is_type_builtin(type_right))) {
1178                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1179                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1180                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1181                         return ASSIGN_SUCCESS;
1182                 }
1183         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1184                 return ASSIGN_WARNING_INT_FROM_POINTER;
1185         }
1186
1187         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1188                 return ASSIGN_SUCCESS;
1189
1190         return ASSIGN_ERROR_INCOMPATIBLE;
1191 }
1192
1193 static expression_t *parse_constant_expression(void)
1194 {
1195         expression_t *result = parse_sub_expression(PREC_CONDITIONAL);
1196
1197         if (!is_constant_expression(result)) {
1198                 errorf(&result->base.source_position,
1199                        "expression '%E' is not constant", result);
1200         }
1201
1202         return result;
1203 }
1204
1205 static expression_t *parse_assignment_expression(void)
1206 {
1207         return parse_sub_expression(PREC_ASSIGNMENT);
1208 }
1209
1210 static string_t parse_string_literals(void)
1211 {
1212         assert(token.type == T_STRING_LITERAL);
1213         string_t result = token.v.string;
1214
1215         next_token();
1216
1217         while (token.type == T_STRING_LITERAL) {
1218                 result = concat_strings(&result, &token.v.string);
1219                 next_token();
1220         }
1221
1222         return result;
1223 }
1224
1225 static const char *const gnu_attribute_names[GNU_AK_LAST] = {
1226         [GNU_AK_CONST]                  = "const",
1227         [GNU_AK_VOLATILE]               = "volatile",
1228         [GNU_AK_CDECL]                  = "cdecl",
1229         [GNU_AK_STDCALL]                = "stdcall",
1230         [GNU_AK_FASTCALL]               = "fastcall",
1231         [GNU_AK_DEPRECATED]             = "deprecated",
1232         [GNU_AK_NOINLINE]               = "noinline",
1233         [GNU_AK_RETURNS_TWICE]          = "returns_twice",
1234         [GNU_AK_NORETURN]               = "noreturn",
1235         [GNU_AK_NAKED]                  = "naked",
1236         [GNU_AK_PURE]                   = "pure",
1237         [GNU_AK_ALWAYS_INLINE]          = "always_inline",
1238         [GNU_AK_MALLOC]                 = "malloc",
1239         [GNU_AK_WEAK]                   = "weak",
1240         [GNU_AK_CONSTRUCTOR]            = "constructor",
1241         [GNU_AK_DESTRUCTOR]             = "destructor",
1242         [GNU_AK_NOTHROW]                = "nothrow",
1243         [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
1244         [GNU_AK_COMMON]                 = "common",
1245         [GNU_AK_NOCOMMON]               = "nocommon",
1246         [GNU_AK_PACKED]                 = "packed",
1247         [GNU_AK_SHARED]                 = "shared",
1248         [GNU_AK_NOTSHARED]              = "notshared",
1249         [GNU_AK_USED]                   = "used",
1250         [GNU_AK_UNUSED]                 = "unused",
1251         [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
1252         [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
1253         [GNU_AK_LONGCALL]               = "longcall",
1254         [GNU_AK_SHORTCALL]              = "shortcall",
1255         [GNU_AK_LONG_CALL]              = "long_call",
1256         [GNU_AK_SHORT_CALL]             = "short_call",
1257         [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
1258         [GNU_AK_INTERRUPT]              = "interrupt",
1259         [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
1260         [GNU_AK_NMI_HANDLER]            = "nmi_handler",
1261         [GNU_AK_NESTING]                = "nesting",
1262         [GNU_AK_NEAR]                   = "near",
1263         [GNU_AK_FAR]                    = "far",
1264         [GNU_AK_SIGNAL]                 = "signal",
1265         [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
1266         [GNU_AK_TINY_DATA]              = "tiny_data",
1267         [GNU_AK_SAVEALL]                = "saveall",
1268         [GNU_AK_FLATTEN]                = "flatten",
1269         [GNU_AK_SSEREGPARM]             = "sseregparm",
1270         [GNU_AK_EXTERNALLY_VISIBLE]     = "externally_visible",
1271         [GNU_AK_RETURN_TWICE]           = "return_twice",
1272         [GNU_AK_MAY_ALIAS]              = "may_alias",
1273         [GNU_AK_MS_STRUCT]              = "ms_struct",
1274         [GNU_AK_GCC_STRUCT]             = "gcc_struct",
1275         [GNU_AK_DLLIMPORT]              = "dllimport",
1276         [GNU_AK_DLLEXPORT]              = "dllexport",
1277         [GNU_AK_ALIGNED]                = "aligned",
1278         [GNU_AK_ALIAS]                  = "alias",
1279         [GNU_AK_SECTION]                = "section",
1280         [GNU_AK_FORMAT]                 = "format",
1281         [GNU_AK_FORMAT_ARG]             = "format_arg",
1282         [GNU_AK_WEAKREF]                = "weakref",
1283         [GNU_AK_NONNULL]                = "nonnull",
1284         [GNU_AK_TLS_MODEL]              = "tls_model",
1285         [GNU_AK_VISIBILITY]             = "visibility",
1286         [GNU_AK_REGPARM]                = "regparm",
1287         [GNU_AK_MODE]                   = "mode",
1288         [GNU_AK_MODEL]                  = "model",
1289         [GNU_AK_TRAP_EXIT]              = "trap_exit",
1290         [GNU_AK_SP_SWITCH]              = "sp_switch",
1291         [GNU_AK_SENTINEL]               = "sentinel"
1292 };
1293
1294 /**
1295  * compare two string, ignoring double underscores on the second.
1296  */
1297 static int strcmp_underscore(const char *s1, const char *s2)
1298 {
1299         if (s2[0] == '_' && s2[1] == '_') {
1300                 size_t len2 = strlen(s2);
1301                 size_t len1 = strlen(s1);
1302                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1303                         return strncmp(s1, s2+2, len2-4);
1304                 }
1305         }
1306
1307         return strcmp(s1, s2);
1308 }
1309
1310 /**
1311  * Allocate a new gnu temporal attribute of given kind.
1312  */
1313 static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
1314 {
1315         gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
1316         attribute->kind            = kind;
1317         attribute->next            = NULL;
1318         attribute->invalid         = false;
1319         attribute->has_arguments   = false;
1320
1321         return attribute;
1322 }
1323
1324 /**
1325  * Parse one constant expression argument of the given attribute.
1326  */
1327 static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
1328 {
1329         expression_t *expression;
1330         add_anchor_token(')');
1331         expression = parse_constant_expression();
1332         rem_anchor_token(')');
1333         expect(')', end_error);
1334         attribute->u.argument = fold_constant(expression);
1335         return;
1336 end_error:
1337         attribute->invalid = true;
1338 }
1339
1340 /**
1341  * Parse a list of constant expressions arguments of the given attribute.
1342  */
1343 static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
1344 {
1345         argument_list_t **list = &attribute->u.arguments;
1346         argument_list_t  *entry;
1347         expression_t     *expression;
1348         add_anchor_token(')');
1349         add_anchor_token(',');
1350         while (true) {
1351                 expression = parse_constant_expression();
1352                 entry = obstack_alloc(&temp_obst, sizeof(entry));
1353                 entry->argument = fold_constant(expression);
1354                 entry->next     = NULL;
1355                 *list = entry;
1356                 list = &entry->next;
1357                 if (token.type != ',')
1358                         break;
1359                 next_token();
1360         }
1361         rem_anchor_token(',');
1362         rem_anchor_token(')');
1363         expect(')', end_error);
1364         return;
1365 end_error:
1366         attribute->invalid = true;
1367 }
1368
1369 /**
1370  * Parse one string literal argument of the given attribute.
1371  */
1372 static void parse_gnu_attribute_string_arg(gnu_attribute_t *attribute,
1373                                            string_t *string)
1374 {
1375         add_anchor_token('(');
1376         if (token.type != T_STRING_LITERAL) {
1377                 parse_error_expected("while parsing attribute directive",
1378                                      T_STRING_LITERAL, NULL);
1379                 goto end_error;
1380         }
1381         *string = parse_string_literals();
1382         rem_anchor_token('(');
1383         expect(')', end_error);
1384         return;
1385 end_error:
1386         attribute->invalid = true;
1387 }
1388
1389 /**
1390  * Parse one tls model of the given attribute.
1391  */
1392 static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
1393 {
1394         static const char *const tls_models[] = {
1395                 "global-dynamic",
1396                 "local-dynamic",
1397                 "initial-exec",
1398                 "local-exec"
1399         };
1400         string_t string = { NULL, 0 };
1401         parse_gnu_attribute_string_arg(attribute, &string);
1402         if (string.begin != NULL) {
1403                 for (size_t i = 0; i < 4; ++i) {
1404                         if (strcmp(tls_models[i], string.begin) == 0) {
1405                                 attribute->u.value = i;
1406                                 return;
1407                         }
1408                 }
1409                 errorf(HERE, "'%s' is an unrecognized tls model", string.begin);
1410         }
1411         attribute->invalid = true;
1412 }
1413
1414 /**
1415  * Parse one tls model of the given attribute.
1416  */
1417 static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
1418 {
1419         static const char *const visibilities[] = {
1420                 "default",
1421                 "protected",
1422                 "hidden",
1423                 "internal"
1424         };
1425         string_t string = { NULL, 0 };
1426         parse_gnu_attribute_string_arg(attribute, &string);
1427         if (string.begin != NULL) {
1428                 for (size_t i = 0; i < 4; ++i) {
1429                         if (strcmp(visibilities[i], string.begin) == 0) {
1430                                 attribute->u.value = i;
1431                                 return;
1432                         }
1433                 }
1434                 errorf(HERE, "'%s' is an unrecognized visibility", string.begin);
1435         }
1436         attribute->invalid = true;
1437 }
1438
1439 /**
1440  * Parse one (code) model of the given attribute.
1441  */
1442 static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
1443 {
1444         static const char *const visibilities[] = {
1445                 "small",
1446                 "medium",
1447                 "large"
1448         };
1449         string_t string = { NULL, 0 };
1450         parse_gnu_attribute_string_arg(attribute, &string);
1451         if (string.begin != NULL) {
1452                 for (int i = 0; i < 3; ++i) {
1453                         if (strcmp(visibilities[i], string.begin) == 0) {
1454                                 attribute->u.value = i;
1455                                 return;
1456                         }
1457                 }
1458                 errorf(HERE, "'%s' is an unrecognized model", string.begin);
1459         }
1460         attribute->invalid = true;
1461 }
1462
1463 /**
1464  * Parse one mode of the given attribute.
1465  */
1466 static void parse_gnu_attribute_mode_arg(gnu_attribute_t *attribute)
1467 {
1468         /* TODO: find out what is allowed here... */
1469
1470         /* at least: byte, word, pointer, list of machine modes
1471          * __XXX___ is interpreted as XXX */
1472         add_anchor_token(')');
1473
1474         if (token.type != T_IDENTIFIER) {
1475                 expect(T_IDENTIFIER, end_error);
1476         }
1477
1478         /* This isn't really correct, the backend should provide a list of machine
1479          * specific modes (according to gcc philosophy that is...) */
1480         const char *symbol_str = token.v.symbol->string;
1481         if (strcmp_underscore("QI",   symbol_str) == 0 ||
1482             strcmp_underscore("byte", symbol_str) == 0) {
1483                 attribute->u.akind = ATOMIC_TYPE_CHAR;
1484         } else if (strcmp_underscore("HI", symbol_str) == 0) {
1485                 attribute->u.akind = ATOMIC_TYPE_SHORT;
1486         } else if (strcmp_underscore("SI",      symbol_str) == 0
1487                 || strcmp_underscore("word",    symbol_str) == 0
1488                 || strcmp_underscore("pointer", symbol_str) == 0) {
1489                 attribute->u.akind = ATOMIC_TYPE_INT;
1490         } else if (strcmp_underscore("DI", symbol_str) == 0) {
1491                 attribute->u.akind = ATOMIC_TYPE_LONGLONG;
1492         } else {
1493                 if (warning.other)
1494                         warningf(HERE, "ignoring unknown mode '%s'", symbol_str);
1495                 attribute->invalid = true;
1496         }
1497         next_token();
1498
1499         rem_anchor_token(')');
1500         expect(')', end_error);
1501         return;
1502 end_error:
1503         attribute->invalid = true;
1504 }
1505
1506 /**
1507  * Parse one interrupt argument of the given attribute.
1508  */
1509 static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
1510 {
1511         static const char *const interrupts[] = {
1512                 "IRQ",
1513                 "FIQ",
1514                 "SWI",
1515                 "ABORT",
1516                 "UNDEF"
1517         };
1518         string_t string = { NULL, 0 };
1519         parse_gnu_attribute_string_arg(attribute, &string);
1520         if (string.begin != NULL) {
1521                 for (size_t i = 0; i < 5; ++i) {
1522                         if (strcmp(interrupts[i], string.begin) == 0) {
1523                                 attribute->u.value = i;
1524                                 return;
1525                         }
1526                 }
1527                 errorf(HERE, "'%s' is not an interrupt", string.begin);
1528         }
1529         attribute->invalid = true;
1530 }
1531
1532 /**
1533  * Parse ( identifier, const expression, const expression )
1534  */
1535 static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
1536 {
1537         static const char *const format_names[] = {
1538                 "printf",
1539                 "scanf",
1540                 "strftime",
1541                 "strfmon"
1542         };
1543         int i;
1544
1545         if (token.type != T_IDENTIFIER) {
1546                 parse_error_expected("while parsing format attribute directive", T_IDENTIFIER, NULL);
1547                 goto end_error;
1548         }
1549         const char *name = token.v.symbol->string;
1550         for (i = 0; i < 4; ++i) {
1551                 if (strcmp_underscore(format_names[i], name) == 0)
1552                         break;
1553         }
1554         if (i >= 4) {
1555                 if (warning.attribute)
1556                         warningf(HERE, "'%s' is an unrecognized format function type", name);
1557         }
1558         next_token();
1559
1560         expect(',', end_error);
1561         add_anchor_token(')');
1562         add_anchor_token(',');
1563         parse_constant_expression();
1564         rem_anchor_token(',');
1565         rem_anchor_token(')');
1566
1567         expect(',', end_error);
1568         add_anchor_token(')');
1569         parse_constant_expression();
1570         rem_anchor_token(')');
1571         expect(')', end_error);
1572         return;
1573 end_error:
1574         attribute->u.value = true;
1575 }
1576
1577 /**
1578  * Check that a given GNU attribute has no arguments.
1579  */
1580 static void check_no_argument(gnu_attribute_t *attribute, const char *name)
1581 {
1582         if (!attribute->has_arguments)
1583                 return;
1584
1585         /* should have no arguments */
1586         errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1587         eat_until_matching_token('(');
1588         /* we have already consumed '(', so we stop before ')', eat it */
1589         eat(')');
1590         attribute->invalid = true;
1591 }
1592
1593 /**
1594  * Parse one GNU attribute.
1595  *
1596  * Note that attribute names can be specified WITH or WITHOUT
1597  * double underscores, ie const or __const__.
1598  *
1599  * The following attributes are parsed without arguments
1600  *  const
1601  *  volatile
1602  *  cdecl
1603  *  stdcall
1604  *  fastcall
1605  *  deprecated
1606  *  noinline
1607  *  noreturn
1608  *  naked
1609  *  pure
1610  *  always_inline
1611  *  malloc
1612  *  weak
1613  *  constructor
1614  *  destructor
1615  *  nothrow
1616  *  transparent_union
1617  *  common
1618  *  nocommon
1619  *  packed
1620  *  shared
1621  *  notshared
1622  *  used
1623  *  unused
1624  *  no_instrument_function
1625  *  warn_unused_result
1626  *  longcall
1627  *  shortcall
1628  *  long_call
1629  *  short_call
1630  *  function_vector
1631  *  interrupt_handler
1632  *  nmi_handler
1633  *  nesting
1634  *  near
1635  *  far
1636  *  signal
1637  *  eightbit_data
1638  *  tiny_data
1639  *  saveall
1640  *  flatten
1641  *  sseregparm
1642  *  externally_visible
1643  *  return_twice
1644  *  may_alias
1645  *  ms_struct
1646  *  gcc_struct
1647  *  dllimport
1648  *  dllexport
1649  *
1650  * The following attributes are parsed with arguments
1651  *  aligned( const expression )
1652  *  alias( string literal )
1653  *  section( string literal )
1654  *  format( identifier, const expression, const expression )
1655  *  format_arg( const expression )
1656  *  tls_model( string literal )
1657  *  visibility( string literal )
1658  *  regparm( const expression )
1659  *  model( string leteral )
1660  *  trap_exit( const expression )
1661  *  sp_switch( string literal )
1662  *
1663  * The following attributes might have arguments
1664  *  weak_ref( string literal )
1665  *  non_null( const expression // ',' )
1666  *  interrupt( string literal )
1667  *  sentinel( constant expression )
1668  */
1669 static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
1670 {
1671         gnu_attribute_t *head      = *attributes;
1672         gnu_attribute_t *last      = *attributes;
1673         decl_modifiers_t modifiers = 0;
1674         gnu_attribute_t *attribute;
1675
1676         eat(T___attribute__);
1677         expect('(', end_error);
1678         expect('(', end_error);
1679
1680         if (token.type != ')') {
1681                 /* find the end of the list */
1682                 if (last != NULL) {
1683                         while (last->next != NULL)
1684                                 last = last->next;
1685                 }
1686
1687                 /* non-empty attribute list */
1688                 while (true) {
1689                         const char *name;
1690                         if (token.type == T_const) {
1691                                 name = "const";
1692                         } else if (token.type == T_volatile) {
1693                                 name = "volatile";
1694                         } else if (token.type == T_cdecl) {
1695                                 /* __attribute__((cdecl)), WITH ms mode */
1696                                 name = "cdecl";
1697                         } else if (token.type == T_IDENTIFIER) {
1698                                 const symbol_t *sym = token.v.symbol;
1699                                 name = sym->string;
1700                         } else {
1701                                 parse_error_expected("while parsing GNU attribute", T_IDENTIFIER, NULL);
1702                                 break;
1703                         }
1704
1705                         next_token();
1706
1707                         int i;
1708                         for (i = 0; i < GNU_AK_LAST; ++i) {
1709                                 if (strcmp_underscore(gnu_attribute_names[i], name) == 0)
1710                                         break;
1711                         }
1712                         gnu_attribute_kind_t kind = (gnu_attribute_kind_t)i;
1713
1714                         attribute = NULL;
1715                         if (kind == GNU_AK_LAST) {
1716                                 if (warning.attribute)
1717                                         warningf(HERE, "'%s' attribute directive ignored", name);
1718
1719                                 /* skip possible arguments */
1720                                 if (token.type == '(') {
1721                                         eat_until_matching_token(')');
1722                                 }
1723                         } else {
1724                                 /* check for arguments */
1725                                 attribute = allocate_gnu_attribute(kind);
1726                                 if (token.type == '(') {
1727                                         next_token();
1728                                         if (token.type == ')') {
1729                                                 /* empty args are allowed */
1730                                                 next_token();
1731                                         } else
1732                                                 attribute->has_arguments = true;
1733                                 }
1734
1735                                 switch (kind) {
1736                                 case GNU_AK_VOLATILE:
1737                                 case GNU_AK_NAKED:
1738                                 case GNU_AK_MALLOC:
1739                                 case GNU_AK_WEAK:
1740                                 case GNU_AK_COMMON:
1741                                 case GNU_AK_NOCOMMON:
1742                                 case GNU_AK_SHARED:
1743                                 case GNU_AK_NOTSHARED:
1744                                 case GNU_AK_NO_INSTRUMENT_FUNCTION:
1745                                 case GNU_AK_WARN_UNUSED_RESULT:
1746                                 case GNU_AK_LONGCALL:
1747                                 case GNU_AK_SHORTCALL:
1748                                 case GNU_AK_LONG_CALL:
1749                                 case GNU_AK_SHORT_CALL:
1750                                 case GNU_AK_FUNCTION_VECTOR:
1751                                 case GNU_AK_INTERRUPT_HANDLER:
1752                                 case GNU_AK_NMI_HANDLER:
1753                                 case GNU_AK_NESTING:
1754                                 case GNU_AK_NEAR:
1755                                 case GNU_AK_FAR:
1756                                 case GNU_AK_SIGNAL:
1757                                 case GNU_AK_EIGTHBIT_DATA:
1758                                 case GNU_AK_TINY_DATA:
1759                                 case GNU_AK_SAVEALL:
1760                                 case GNU_AK_FLATTEN:
1761                                 case GNU_AK_SSEREGPARM:
1762                                 case GNU_AK_EXTERNALLY_VISIBLE:
1763                                 case GNU_AK_RETURN_TWICE:
1764                                 case GNU_AK_MAY_ALIAS:
1765                                 case GNU_AK_MS_STRUCT:
1766                                 case GNU_AK_GCC_STRUCT:
1767                                         goto no_arg;
1768
1769                                 case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
1770                                 case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
1771                                 case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
1772                                 case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
1773                                 case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
1774                                 case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
1775                                 case GNU_AK_CONST:             modifiers |= DM_CONST;             goto no_arg;
1776                                 case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
1777                                 case GNU_AK_DLLIMPORT:         modifiers |= DM_DLLIMPORT;         goto no_arg;
1778                                 case GNU_AK_DLLEXPORT:         modifiers |= DM_DLLEXPORT;         goto no_arg;
1779                                 case GNU_AK_PACKED:            modifiers |= DM_PACKED;            goto no_arg;
1780                                 case GNU_AK_NOINLINE:          modifiers |= DM_NOINLINE;          goto no_arg;
1781                                 case GNU_AK_RETURNS_TWICE:     modifiers |= DM_RETURNS_TWICE;     goto no_arg;
1782                                 case GNU_AK_NORETURN:          modifiers |= DM_NORETURN;          goto no_arg;
1783                                 case GNU_AK_NOTHROW:           modifiers |= DM_NOTHROW;           goto no_arg;
1784                                 case GNU_AK_TRANSPARENT_UNION: modifiers |= DM_TRANSPARENT_UNION; goto no_arg;
1785                                 case GNU_AK_CONSTRUCTOR:       modifiers |= DM_CONSTRUCTOR;       goto no_arg;
1786                                 case GNU_AK_DESTRUCTOR:        modifiers |= DM_DESTRUCTOR;        goto no_arg;
1787                                 case GNU_AK_DEPRECATED:        modifiers |= DM_DEPRECATED;        goto no_arg;
1788
1789                                 case GNU_AK_ALIGNED:
1790                                         /* __align__ may be used without an argument */
1791                                         if (attribute->has_arguments) {
1792                                                 parse_gnu_attribute_const_arg(attribute);
1793                                         }
1794                                         break;
1795
1796                                 case GNU_AK_FORMAT_ARG:
1797                                 case GNU_AK_REGPARM:
1798                                 case GNU_AK_TRAP_EXIT:
1799                                         if (!attribute->has_arguments) {
1800                                                 /* should have arguments */
1801                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1802                                                 attribute->invalid = true;
1803                                         } else
1804                                                 parse_gnu_attribute_const_arg(attribute);
1805                                         break;
1806                                 case GNU_AK_ALIAS:
1807                                 case GNU_AK_SECTION:
1808                                 case GNU_AK_SP_SWITCH:
1809                                         if (!attribute->has_arguments) {
1810                                                 /* should have arguments */
1811                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1812                                                 attribute->invalid = true;
1813                                         } else
1814                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1815                                         break;
1816                                 case GNU_AK_FORMAT:
1817                                         if (!attribute->has_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_format_args(attribute);
1823                                         break;
1824                                 case GNU_AK_WEAKREF:
1825                                         /* may have one string argument */
1826                                         if (attribute->has_arguments)
1827                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1828                                         break;
1829                                 case GNU_AK_NONNULL:
1830                                         if (attribute->has_arguments)
1831                                                 parse_gnu_attribute_const_arg_list(attribute);
1832                                         break;
1833                                 case GNU_AK_TLS_MODEL:
1834                                         if (!attribute->has_arguments) {
1835                                                 /* should have arguments */
1836                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1837                                         } else
1838                                                 parse_gnu_attribute_tls_model_arg(attribute);
1839                                         break;
1840                                 case GNU_AK_VISIBILITY:
1841                                         if (!attribute->has_arguments) {
1842                                                 /* should have arguments */
1843                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1844                                         } else
1845                                                 parse_gnu_attribute_visibility_arg(attribute);
1846                                         break;
1847                                 case GNU_AK_MODEL:
1848                                         if (!attribute->has_arguments) {
1849                                                 /* should have arguments */
1850                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1851                                         } else {
1852                                                 parse_gnu_attribute_model_arg(attribute);
1853                                         }
1854                                         break;
1855                                 case GNU_AK_MODE:
1856                                         if (!attribute->has_arguments) {
1857                                                 /* should have arguments */
1858                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1859                                         } else {
1860                                                 parse_gnu_attribute_mode_arg(attribute);
1861                                         }
1862                                         break;
1863                                 case GNU_AK_INTERRUPT:
1864                                         /* may have one string argument */
1865                                         if (attribute->has_arguments)
1866                                                 parse_gnu_attribute_interrupt_arg(attribute);
1867                                         break;
1868                                 case GNU_AK_SENTINEL:
1869                                         /* may have one string argument */
1870                                         if (attribute->has_arguments)
1871                                                 parse_gnu_attribute_const_arg(attribute);
1872                                         break;
1873                                 case GNU_AK_LAST:
1874                                         /* already handled */
1875                                         break;
1876
1877 no_arg:
1878                                         check_no_argument(attribute, name);
1879                                 }
1880                         }
1881                         if (attribute != NULL) {
1882                                 if (last != NULL) {
1883                                         last->next = attribute;
1884                                         last       = attribute;
1885                                 } else {
1886                                         head = last = attribute;
1887                                 }
1888                         }
1889
1890                         if (token.type != ',')
1891                                 break;
1892                         next_token();
1893                 }
1894         }
1895         expect(')', end_error);
1896         expect(')', end_error);
1897 end_error:
1898         *attributes = head;
1899
1900         return modifiers;
1901 }
1902
1903 /**
1904  * Parse GNU attributes.
1905  */
1906 static decl_modifiers_t parse_attributes(gnu_attribute_t **attributes)
1907 {
1908         decl_modifiers_t modifiers = 0;
1909
1910         while (true) {
1911                 switch (token.type) {
1912                 case T___attribute__:
1913                         modifiers |= parse_gnu_attribute(attributes);
1914                         continue;
1915
1916                 case T_asm:
1917                         next_token();
1918                         expect('(', end_error);
1919                         if (token.type != T_STRING_LITERAL) {
1920                                 parse_error_expected("while parsing assembler attribute",
1921                                                      T_STRING_LITERAL, NULL);
1922                                 eat_until_matching_token('(');
1923                                 break;
1924                         } else {
1925                                 parse_string_literals();
1926                         }
1927                         expect(')', end_error);
1928                         continue;
1929
1930                 case T_cdecl:     modifiers |= DM_CDECL;    break;
1931                 case T__fastcall: modifiers |= DM_FASTCALL; break;
1932                 case T__stdcall:  modifiers |= DM_STDCALL;  break;
1933
1934                 case T___thiscall:
1935                         /* TODO record modifier */
1936                         if (warning.other)
1937                                 warningf(HERE, "Ignoring declaration modifier %K", &token);
1938                         break;
1939
1940 end_error:
1941                 default: return modifiers;
1942                 }
1943
1944                 next_token();
1945         }
1946 }
1947
1948 static void mark_vars_read(expression_t *expr, entity_t *lhs_ent);
1949
1950 static entity_t *determine_lhs_ent(expression_t *const expr,
1951                                    entity_t *lhs_ent)
1952 {
1953         switch (expr->kind) {
1954                 case EXPR_REFERENCE: {
1955                         entity_t *const entity = expr->reference.entity;
1956                         /* we should only find variables as lvalues... */
1957                         if (entity->base.kind != ENTITY_VARIABLE
1958                                         && entity->base.kind != ENTITY_PARAMETER)
1959                                 return NULL;
1960
1961                         return entity;
1962                 }
1963
1964                 case EXPR_ARRAY_ACCESS: {
1965                         expression_t *const ref = expr->array_access.array_ref;
1966                         entity_t     *      ent = NULL;
1967                         if (is_type_array(skip_typeref(revert_automatic_type_conversion(ref)))) {
1968                                 ent     = determine_lhs_ent(ref, lhs_ent);
1969                                 lhs_ent = ent;
1970                         } else {
1971                                 mark_vars_read(expr->select.compound, lhs_ent);
1972                         }
1973                         mark_vars_read(expr->array_access.index, lhs_ent);
1974                         return ent;
1975                 }
1976
1977                 case EXPR_SELECT: {
1978                         if (is_type_compound(skip_typeref(expr->base.type))) {
1979                                 return determine_lhs_ent(expr->select.compound, lhs_ent);
1980                         } else {
1981                                 mark_vars_read(expr->select.compound, lhs_ent);
1982                                 return NULL;
1983                         }
1984                 }
1985
1986                 case EXPR_UNARY_DEREFERENCE: {
1987                         expression_t *const val = expr->unary.value;
1988                         if (val->kind == EXPR_UNARY_TAKE_ADDRESS) {
1989                                 /* *&x is a NOP */
1990                                 return determine_lhs_ent(val->unary.value, lhs_ent);
1991                         } else {
1992                                 mark_vars_read(val, NULL);
1993                                 return NULL;
1994                         }
1995                 }
1996
1997                 default:
1998                         mark_vars_read(expr, NULL);
1999                         return NULL;
2000         }
2001 }
2002
2003 #define ENT_ANY ((entity_t*)-1)
2004
2005 /**
2006  * Mark declarations, which are read.  This is used to detect variables, which
2007  * are never read.
2008  * Example:
2009  * x = x + 1;
2010  *   x is not marked as "read", because it is only read to calculate its own new
2011  *   value.
2012  *
2013  * x += y; y += x;
2014  *   x and y are not detected as "not read", because multiple variables are
2015  *   involved.
2016  */
2017 static void mark_vars_read(expression_t *const expr, entity_t *lhs_ent)
2018 {
2019         switch (expr->kind) {
2020                 case EXPR_REFERENCE: {
2021                         entity_t *const entity = expr->reference.entity;
2022                         if (entity->kind != ENTITY_VARIABLE
2023                                         && entity->kind != ENTITY_PARAMETER)
2024                                 return;
2025
2026                         if (lhs_ent != entity && lhs_ent != ENT_ANY) {
2027                                 if (entity->kind == ENTITY_VARIABLE) {
2028                                         entity->variable.read = true;
2029                                 } else {
2030                                         entity->parameter.read = true;
2031                                 }
2032                         }
2033                         return;
2034                 }
2035
2036                 case EXPR_CALL:
2037                         // TODO respect pure/const
2038                         mark_vars_read(expr->call.function, NULL);
2039                         for (call_argument_t *arg = expr->call.arguments; arg != NULL; arg = arg->next) {
2040                                 mark_vars_read(arg->expression, NULL);
2041                         }
2042                         return;
2043
2044                 case EXPR_CONDITIONAL:
2045                         // TODO lhs_decl should depend on whether true/false have an effect
2046                         mark_vars_read(expr->conditional.condition, NULL);
2047                         if (expr->conditional.true_expression != NULL)
2048                                 mark_vars_read(expr->conditional.true_expression, lhs_ent);
2049                         mark_vars_read(expr->conditional.false_expression, lhs_ent);
2050                         return;
2051
2052                 case EXPR_SELECT:
2053                         if (lhs_ent == ENT_ANY
2054                                         && !is_type_compound(skip_typeref(expr->base.type)))
2055                                 lhs_ent = NULL;
2056                         mark_vars_read(expr->select.compound, lhs_ent);
2057                         return;
2058
2059                 case EXPR_ARRAY_ACCESS: {
2060                         expression_t *const ref = expr->array_access.array_ref;
2061                         mark_vars_read(ref, lhs_ent);
2062                         lhs_ent = determine_lhs_ent(ref, lhs_ent);
2063                         mark_vars_read(expr->array_access.index, lhs_ent);
2064                         return;
2065                 }
2066
2067                 case EXPR_VA_ARG:
2068                         mark_vars_read(expr->va_arge.ap, lhs_ent);
2069                         return;
2070
2071                 case EXPR_UNARY_CAST:
2072                         /* Special case: Use void cast to mark a variable as "read" */
2073                         if (is_type_atomic(skip_typeref(expr->base.type), ATOMIC_TYPE_VOID))
2074                                 lhs_ent = NULL;
2075                         goto unary;
2076
2077
2078                 case EXPR_UNARY_THROW:
2079                         if (expr->unary.value == NULL)
2080                                 return;
2081                         /* FALLTHROUGH */
2082                 case EXPR_UNARY_DEREFERENCE:
2083                 case EXPR_UNARY_DELETE:
2084                 case EXPR_UNARY_DELETE_ARRAY:
2085                         if (lhs_ent == ENT_ANY)
2086                                 lhs_ent = NULL;
2087                         goto unary;
2088
2089                 case EXPR_UNARY_NEGATE:
2090                 case EXPR_UNARY_PLUS:
2091                 case EXPR_UNARY_BITWISE_NEGATE:
2092                 case EXPR_UNARY_NOT:
2093                 case EXPR_UNARY_TAKE_ADDRESS:
2094                 case EXPR_UNARY_POSTFIX_INCREMENT:
2095                 case EXPR_UNARY_POSTFIX_DECREMENT:
2096                 case EXPR_UNARY_PREFIX_INCREMENT:
2097                 case EXPR_UNARY_PREFIX_DECREMENT:
2098                 case EXPR_UNARY_CAST_IMPLICIT:
2099                 case EXPR_UNARY_ASSUME:
2100 unary:
2101                         mark_vars_read(expr->unary.value, lhs_ent);
2102                         return;
2103
2104                 case EXPR_BINARY_ADD:
2105                 case EXPR_BINARY_SUB:
2106                 case EXPR_BINARY_MUL:
2107                 case EXPR_BINARY_DIV:
2108                 case EXPR_BINARY_MOD:
2109                 case EXPR_BINARY_EQUAL:
2110                 case EXPR_BINARY_NOTEQUAL:
2111                 case EXPR_BINARY_LESS:
2112                 case EXPR_BINARY_LESSEQUAL:
2113                 case EXPR_BINARY_GREATER:
2114                 case EXPR_BINARY_GREATEREQUAL:
2115                 case EXPR_BINARY_BITWISE_AND:
2116                 case EXPR_BINARY_BITWISE_OR:
2117                 case EXPR_BINARY_BITWISE_XOR:
2118                 case EXPR_BINARY_LOGICAL_AND:
2119                 case EXPR_BINARY_LOGICAL_OR:
2120                 case EXPR_BINARY_SHIFTLEFT:
2121                 case EXPR_BINARY_SHIFTRIGHT:
2122                 case EXPR_BINARY_COMMA:
2123                 case EXPR_BINARY_ISGREATER:
2124                 case EXPR_BINARY_ISGREATEREQUAL:
2125                 case EXPR_BINARY_ISLESS:
2126                 case EXPR_BINARY_ISLESSEQUAL:
2127                 case EXPR_BINARY_ISLESSGREATER:
2128                 case EXPR_BINARY_ISUNORDERED:
2129                         mark_vars_read(expr->binary.left,  lhs_ent);
2130                         mark_vars_read(expr->binary.right, lhs_ent);
2131                         return;
2132
2133                 case EXPR_BINARY_ASSIGN:
2134                 case EXPR_BINARY_MUL_ASSIGN:
2135                 case EXPR_BINARY_DIV_ASSIGN:
2136                 case EXPR_BINARY_MOD_ASSIGN:
2137                 case EXPR_BINARY_ADD_ASSIGN:
2138                 case EXPR_BINARY_SUB_ASSIGN:
2139                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:
2140                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:
2141                 case EXPR_BINARY_BITWISE_AND_ASSIGN:
2142                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:
2143                 case EXPR_BINARY_BITWISE_OR_ASSIGN: {
2144                         if (lhs_ent == ENT_ANY)
2145                                 lhs_ent = NULL;
2146                         lhs_ent = determine_lhs_ent(expr->binary.left, lhs_ent);
2147                         mark_vars_read(expr->binary.right, lhs_ent);
2148                         return;
2149                 }
2150
2151                 case EXPR_VA_START:
2152                         determine_lhs_ent(expr->va_starte.ap, lhs_ent);
2153                         return;
2154
2155                 case EXPR_UNKNOWN:
2156                 case EXPR_INVALID:
2157                 case EXPR_CONST:
2158                 case EXPR_CHARACTER_CONSTANT:
2159                 case EXPR_WIDE_CHARACTER_CONSTANT:
2160                 case EXPR_STRING_LITERAL:
2161                 case EXPR_WIDE_STRING_LITERAL:
2162                 case EXPR_COMPOUND_LITERAL: // TODO init?
2163                 case EXPR_SIZEOF:
2164                 case EXPR_CLASSIFY_TYPE:
2165                 case EXPR_ALIGNOF:
2166                 case EXPR_FUNCNAME:
2167                 case EXPR_BUILTIN_SYMBOL:
2168                 case EXPR_BUILTIN_CONSTANT_P:
2169                 case EXPR_BUILTIN_PREFETCH:
2170                 case EXPR_OFFSETOF:
2171                 case EXPR_STATEMENT: // TODO
2172                 case EXPR_LABEL_ADDRESS:
2173                 case EXPR_REFERENCE_ENUM_VALUE:
2174                         return;
2175         }
2176
2177         panic("unhandled expression");
2178 }
2179
2180 static designator_t *parse_designation(void)
2181 {
2182         designator_t *result = NULL;
2183         designator_t *last   = NULL;
2184
2185         while (true) {
2186                 designator_t *designator;
2187                 switch (token.type) {
2188                 case '[':
2189                         designator = allocate_ast_zero(sizeof(designator[0]));
2190                         designator->source_position = token.source_position;
2191                         next_token();
2192                         add_anchor_token(']');
2193                         designator->array_index = parse_constant_expression();
2194                         rem_anchor_token(']');
2195                         expect(']', end_error);
2196                         break;
2197                 case '.':
2198                         designator = allocate_ast_zero(sizeof(designator[0]));
2199                         designator->source_position = token.source_position;
2200                         next_token();
2201                         if (token.type != T_IDENTIFIER) {
2202                                 parse_error_expected("while parsing designator",
2203                                                      T_IDENTIFIER, NULL);
2204                                 return NULL;
2205                         }
2206                         designator->symbol = token.v.symbol;
2207                         next_token();
2208                         break;
2209                 default:
2210                         expect('=', end_error);
2211                         return result;
2212                 }
2213
2214                 assert(designator != NULL);
2215                 if (last != NULL) {
2216                         last->next = designator;
2217                 } else {
2218                         result = designator;
2219                 }
2220                 last = designator;
2221         }
2222 end_error:
2223         return NULL;
2224 }
2225
2226 static initializer_t *initializer_from_string(array_type_t *type,
2227                                               const string_t *const string)
2228 {
2229         /* TODO: check len vs. size of array type */
2230         (void) type;
2231
2232         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
2233         initializer->string.string = *string;
2234
2235         return initializer;
2236 }
2237
2238 static initializer_t *initializer_from_wide_string(array_type_t *const type,
2239                                                    wide_string_t *const string)
2240 {
2241         /* TODO: check len vs. size of array type */
2242         (void) type;
2243
2244         initializer_t *const initializer =
2245                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
2246         initializer->wide_string.string = *string;
2247
2248         return initializer;
2249 }
2250
2251 /**
2252  * Build an initializer from a given expression.
2253  */
2254 static initializer_t *initializer_from_expression(type_t *orig_type,
2255                                                   expression_t *expression)
2256 {
2257         /* TODO check that expression is a constant expression */
2258
2259         /* § 6.7.8.14/15 char array may be initialized by string literals */
2260         type_t *type           = skip_typeref(orig_type);
2261         type_t *expr_type_orig = expression->base.type;
2262         type_t *expr_type      = skip_typeref(expr_type_orig);
2263         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
2264                 array_type_t *const array_type   = &type->array;
2265                 type_t       *const element_type = skip_typeref(array_type->element_type);
2266
2267                 if (element_type->kind == TYPE_ATOMIC) {
2268                         atomic_type_kind_t akind = element_type->atomic.akind;
2269                         switch (expression->kind) {
2270                                 case EXPR_STRING_LITERAL:
2271                                         if (akind == ATOMIC_TYPE_CHAR
2272                                                         || akind == ATOMIC_TYPE_SCHAR
2273                                                         || akind == ATOMIC_TYPE_UCHAR) {
2274                                                 return initializer_from_string(array_type,
2275                                                         &expression->string.value);
2276                                         }
2277
2278                                 case EXPR_WIDE_STRING_LITERAL: {
2279                                         type_t *bare_wchar_type = skip_typeref(type_wchar_t);
2280                                         if (get_unqualified_type(element_type) == bare_wchar_type) {
2281                                                 return initializer_from_wide_string(array_type,
2282                                                         &expression->wide_string.value);
2283                                         }
2284                                 }
2285
2286                                 default:
2287                                         break;
2288                         }
2289                 }
2290         }
2291
2292         assign_error_t error = semantic_assign(type, expression);
2293         if (error == ASSIGN_ERROR_INCOMPATIBLE)
2294                 return NULL;
2295         report_assign_error(error, type, expression, "initializer",
2296                             &expression->base.source_position);
2297
2298         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
2299 #if 0
2300         if (type->kind == TYPE_BITFIELD) {
2301                 type = type->bitfield.base_type;
2302         }
2303 #endif
2304         result->value.value = create_implicit_cast(expression, type);
2305
2306         return result;
2307 }
2308
2309 /**
2310  * Checks if a given expression can be used as an constant initializer.
2311  */
2312 static bool is_initializer_constant(const expression_t *expression)
2313 {
2314         return is_constant_expression(expression)
2315                 || is_address_constant(expression);
2316 }
2317
2318 /**
2319  * Parses an scalar initializer.
2320  *
2321  * § 6.7.8.11; eat {} without warning
2322  */
2323 static initializer_t *parse_scalar_initializer(type_t *type,
2324                                                bool must_be_constant)
2325 {
2326         /* there might be extra {} hierarchies */
2327         int braces = 0;
2328         if (token.type == '{') {
2329                 if (warning.other)
2330                         warningf(HERE, "extra curly braces around scalar initializer");
2331                 do {
2332                         ++braces;
2333                         next_token();
2334                 } while (token.type == '{');
2335         }
2336
2337         expression_t *expression = parse_assignment_expression();
2338         mark_vars_read(expression, NULL);
2339         if (must_be_constant && !is_initializer_constant(expression)) {
2340                 errorf(&expression->base.source_position,
2341                        "Initialisation expression '%E' is not constant",
2342                        expression);
2343         }
2344
2345         initializer_t *initializer = initializer_from_expression(type, expression);
2346
2347         if (initializer == NULL) {
2348                 errorf(&expression->base.source_position,
2349                        "expression '%E' (type '%T') doesn't match expected type '%T'",
2350                        expression, expression->base.type, type);
2351                 /* TODO */
2352                 return NULL;
2353         }
2354
2355         bool additional_warning_displayed = false;
2356         while (braces > 0) {
2357                 if (token.type == ',') {
2358                         next_token();
2359                 }
2360                 if (token.type != '}') {
2361                         if (!additional_warning_displayed && warning.other) {
2362                                 warningf(HERE, "additional elements in scalar initializer");
2363                                 additional_warning_displayed = true;
2364                         }
2365                 }
2366                 eat_block();
2367                 braces--;
2368         }
2369
2370         return initializer;
2371 }
2372
2373 /**
2374  * An entry in the type path.
2375  */
2376 typedef struct type_path_entry_t type_path_entry_t;
2377 struct type_path_entry_t {
2378         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
2379         union {
2380                 size_t         index;          /**< For array types: the current index. */
2381                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
2382         } v;
2383 };
2384
2385 /**
2386  * A type path expression a position inside compound or array types.
2387  */
2388 typedef struct type_path_t type_path_t;
2389 struct type_path_t {
2390         type_path_entry_t *path;         /**< An flexible array containing the current path. */
2391         type_t            *top_type;     /**< type of the element the path points */
2392         size_t             max_index;    /**< largest index in outermost array */
2393 };
2394
2395 /**
2396  * Prints a type path for debugging.
2397  */
2398 static __attribute__((unused)) void debug_print_type_path(
2399                 const type_path_t *path)
2400 {
2401         size_t len = ARR_LEN(path->path);
2402
2403         for (size_t i = 0; i < len; ++i) {
2404                 const type_path_entry_t *entry = & path->path[i];
2405
2406                 type_t *type = skip_typeref(entry->type);
2407                 if (is_type_compound(type)) {
2408                         /* in gcc mode structs can have no members */
2409                         if (entry->v.compound_entry == NULL) {
2410                                 assert(i == len-1);
2411                                 continue;
2412                         }
2413                         fprintf(stderr, ".%s",
2414                                 entry->v.compound_entry->base.symbol->string);
2415                 } else if (is_type_array(type)) {
2416                         fprintf(stderr, "[%u]", (unsigned) entry->v.index);
2417                 } else {
2418                         fprintf(stderr, "-INVALID-");
2419                 }
2420         }
2421         if (path->top_type != NULL) {
2422                 fprintf(stderr, "  (");
2423                 print_type(path->top_type);
2424                 fprintf(stderr, ")");
2425         }
2426 }
2427
2428 /**
2429  * Return the top type path entry, ie. in a path
2430  * (type).a.b returns the b.
2431  */
2432 static type_path_entry_t *get_type_path_top(const type_path_t *path)
2433 {
2434         size_t len = ARR_LEN(path->path);
2435         assert(len > 0);
2436         return &path->path[len-1];
2437 }
2438
2439 /**
2440  * Enlarge the type path by an (empty) element.
2441  */
2442 static type_path_entry_t *append_to_type_path(type_path_t *path)
2443 {
2444         size_t len = ARR_LEN(path->path);
2445         ARR_RESIZE(type_path_entry_t, path->path, len+1);
2446
2447         type_path_entry_t *result = & path->path[len];
2448         memset(result, 0, sizeof(result[0]));
2449         return result;
2450 }
2451
2452 /**
2453  * Descending into a sub-type. Enter the scope of the current top_type.
2454  */
2455 static void descend_into_subtype(type_path_t *path)
2456 {
2457         type_t *orig_top_type = path->top_type;
2458         type_t *top_type      = skip_typeref(orig_top_type);
2459
2460         type_path_entry_t *top = append_to_type_path(path);
2461         top->type              = top_type;
2462
2463         if (is_type_compound(top_type)) {
2464                 compound_t *compound  = top_type->compound.compound;
2465                 entity_t   *entry     = compound->members.entities;
2466
2467                 if (entry != NULL) {
2468                         assert(entry->kind == ENTITY_COMPOUND_MEMBER);
2469                         top->v.compound_entry = &entry->declaration;
2470                         path->top_type = entry->declaration.type;
2471                 } else {
2472                         path->top_type = NULL;
2473                 }
2474         } else if (is_type_array(top_type)) {
2475                 top->v.index   = 0;
2476                 path->top_type = top_type->array.element_type;
2477         } else {
2478                 assert(!is_type_valid(top_type));
2479         }
2480 }
2481
2482 /**
2483  * Pop an entry from the given type path, ie. returning from
2484  * (type).a.b to (type).a
2485  */
2486 static void ascend_from_subtype(type_path_t *path)
2487 {
2488         type_path_entry_t *top = get_type_path_top(path);
2489
2490         path->top_type = top->type;
2491
2492         size_t len = ARR_LEN(path->path);
2493         ARR_RESIZE(type_path_entry_t, path->path, len-1);
2494 }
2495
2496 /**
2497  * Pop entries from the given type path until the given
2498  * path level is reached.
2499  */
2500 static void ascend_to(type_path_t *path, size_t top_path_level)
2501 {
2502         size_t len = ARR_LEN(path->path);
2503
2504         while (len > top_path_level) {
2505                 ascend_from_subtype(path);
2506                 len = ARR_LEN(path->path);
2507         }
2508 }
2509
2510 static bool walk_designator(type_path_t *path, const designator_t *designator,
2511                             bool used_in_offsetof)
2512 {
2513         for (; designator != NULL; designator = designator->next) {
2514                 type_path_entry_t *top       = get_type_path_top(path);
2515                 type_t            *orig_type = top->type;
2516
2517                 type_t *type = skip_typeref(orig_type);
2518
2519                 if (designator->symbol != NULL) {
2520                         symbol_t *symbol = designator->symbol;
2521                         if (!is_type_compound(type)) {
2522                                 if (is_type_valid(type)) {
2523                                         errorf(&designator->source_position,
2524                                                "'.%Y' designator used for non-compound type '%T'",
2525                                                symbol, orig_type);
2526                                 }
2527
2528                                 top->type             = type_error_type;
2529                                 top->v.compound_entry = NULL;
2530                                 orig_type             = type_error_type;
2531                         } else {
2532                                 compound_t *compound = type->compound.compound;
2533                                 entity_t   *iter     = compound->members.entities;
2534                                 for (; iter != NULL; iter = iter->base.next) {
2535                                         if (iter->base.symbol == symbol) {
2536                                                 break;
2537                                         }
2538                                 }
2539                                 if (iter == NULL) {
2540                                         errorf(&designator->source_position,
2541                                                "'%T' has no member named '%Y'", orig_type, symbol);
2542                                         goto failed;
2543                                 }
2544                                 assert(iter->kind == ENTITY_COMPOUND_MEMBER);
2545                                 if (used_in_offsetof) {
2546                                         type_t *real_type = skip_typeref(iter->declaration.type);
2547                                         if (real_type->kind == TYPE_BITFIELD) {
2548                                                 errorf(&designator->source_position,
2549                                                        "offsetof designator '%Y' may not specify bitfield",
2550                                                        symbol);
2551                                                 goto failed;
2552                                         }
2553                                 }
2554
2555                                 top->type             = orig_type;
2556                                 top->v.compound_entry = &iter->declaration;
2557                                 orig_type             = iter->declaration.type;
2558                         }
2559                 } else {
2560                         expression_t *array_index = designator->array_index;
2561                         assert(designator->array_index != NULL);
2562
2563                         if (!is_type_array(type)) {
2564                                 if (is_type_valid(type)) {
2565                                         errorf(&designator->source_position,
2566                                                "[%E] designator used for non-array type '%T'",
2567                                                array_index, orig_type);
2568                                 }
2569                                 goto failed;
2570                         }
2571
2572                         long index = fold_constant(array_index);
2573                         if (!used_in_offsetof) {
2574                                 if (index < 0) {
2575                                         errorf(&designator->source_position,
2576                                                "array index [%E] must be positive", array_index);
2577                                 } else if (type->array.size_constant) {
2578                                         long array_size = type->array.size;
2579                                         if (index >= array_size) {
2580                                                 errorf(&designator->source_position,
2581                                                        "designator [%E] (%d) exceeds array size %d",
2582                                                        array_index, index, array_size);
2583                                         }
2584                                 }
2585                         }
2586
2587                         top->type    = orig_type;
2588                         top->v.index = (size_t) index;
2589                         orig_type    = type->array.element_type;
2590                 }
2591                 path->top_type = orig_type;
2592
2593                 if (designator->next != NULL) {
2594                         descend_into_subtype(path);
2595                 }
2596         }
2597         return true;
2598
2599 failed:
2600         return false;
2601 }
2602
2603 static void advance_current_object(type_path_t *path, size_t top_path_level)
2604 {
2605         type_path_entry_t *top = get_type_path_top(path);
2606
2607         type_t *type = skip_typeref(top->type);
2608         if (is_type_union(type)) {
2609                 /* in unions only the first element is initialized */
2610                 top->v.compound_entry = NULL;
2611         } else if (is_type_struct(type)) {
2612                 declaration_t *entry = top->v.compound_entry;
2613
2614                 entity_t *next_entity = entry->base.next;
2615                 if (next_entity != NULL) {
2616                         assert(is_declaration(next_entity));
2617                         entry = &next_entity->declaration;
2618                 } else {
2619                         entry = NULL;
2620                 }
2621
2622                 top->v.compound_entry = entry;
2623                 if (entry != NULL) {
2624                         path->top_type = entry->type;
2625                         return;
2626                 }
2627         } else if (is_type_array(type)) {
2628                 assert(is_type_array(type));
2629
2630                 top->v.index++;
2631
2632                 if (!type->array.size_constant || top->v.index < type->array.size) {
2633                         return;
2634                 }
2635         } else {
2636                 assert(!is_type_valid(type));
2637                 return;
2638         }
2639
2640         /* we're past the last member of the current sub-aggregate, try if we
2641          * can ascend in the type hierarchy and continue with another subobject */
2642         size_t len = ARR_LEN(path->path);
2643
2644         if (len > top_path_level) {
2645                 ascend_from_subtype(path);
2646                 advance_current_object(path, top_path_level);
2647         } else {
2648                 path->top_type = NULL;
2649         }
2650 }
2651
2652 /**
2653  * skip until token is found.
2654  */
2655 static void skip_until(int type)
2656 {
2657         while (token.type != type) {
2658                 if (token.type == T_EOF)
2659                         return;
2660                 next_token();
2661         }
2662 }
2663
2664 /**
2665  * skip any {...} blocks until a closing bracket is reached.
2666  */
2667 static void skip_initializers(void)
2668 {
2669         if (token.type == '{')
2670                 next_token();
2671
2672         while (token.type != '}') {
2673                 if (token.type == T_EOF)
2674                         return;
2675                 if (token.type == '{') {
2676                         eat_block();
2677                         continue;
2678                 }
2679                 next_token();
2680         }
2681 }
2682
2683 static initializer_t *create_empty_initializer(void)
2684 {
2685         static initializer_t empty_initializer
2686                 = { .list = { { INITIALIZER_LIST }, 0 } };
2687         return &empty_initializer;
2688 }
2689
2690 /**
2691  * Parse a part of an initialiser for a struct or union,
2692  */
2693 static initializer_t *parse_sub_initializer(type_path_t *path,
2694                 type_t *outer_type, size_t top_path_level,
2695                 parse_initializer_env_t *env)
2696 {
2697         if (token.type == '}') {
2698                 /* empty initializer */
2699                 return create_empty_initializer();
2700         }
2701
2702         type_t *orig_type = path->top_type;
2703         type_t *type      = NULL;
2704
2705         if (orig_type == NULL) {
2706                 /* We are initializing an empty compound. */
2707         } else {
2708                 type = skip_typeref(orig_type);
2709         }
2710
2711         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2712
2713         while (true) {
2714                 designator_t *designator = NULL;
2715                 if (token.type == '.' || token.type == '[') {
2716                         designator = parse_designation();
2717                         goto finish_designator;
2718                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2719                         /* GNU-style designator ("identifier: value") */
2720                         designator = allocate_ast_zero(sizeof(designator[0]));
2721                         designator->source_position = token.source_position;
2722                         designator->symbol          = token.v.symbol;
2723                         eat(T_IDENTIFIER);
2724                         eat(':');
2725
2726 finish_designator:
2727                         /* reset path to toplevel, evaluate designator from there */
2728                         ascend_to(path, top_path_level);
2729                         if (!walk_designator(path, designator, false)) {
2730                                 /* can't continue after designation error */
2731                                 goto end_error;
2732                         }
2733
2734                         initializer_t *designator_initializer
2735                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2736                         designator_initializer->designator.designator = designator;
2737                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2738
2739                         orig_type = path->top_type;
2740                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2741                 }
2742
2743                 initializer_t *sub;
2744
2745                 if (token.type == '{') {
2746                         if (type != NULL && is_type_scalar(type)) {
2747                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2748                         } else {
2749                                 eat('{');
2750                                 if (type == NULL) {
2751                                         if (env->entity != NULL) {
2752                                                 errorf(HERE,
2753                                                      "extra brace group at end of initializer for '%Y'",
2754                                                      env->entity->base.symbol);
2755                                         } else {
2756                                                 errorf(HERE, "extra brace group at end of initializer");
2757                                         }
2758                                 } else
2759                                         descend_into_subtype(path);
2760
2761                                 add_anchor_token('}');
2762                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2763                                                             env);
2764                                 rem_anchor_token('}');
2765
2766                                 if (type != NULL) {
2767                                         ascend_from_subtype(path);
2768                                         expect('}', end_error);
2769                                 } else {
2770                                         expect('}', end_error);
2771                                         goto error_parse_next;
2772                                 }
2773                         }
2774                 } else {
2775                         /* must be an expression */
2776                         expression_t *expression = parse_assignment_expression();
2777                         mark_vars_read(expression, NULL);
2778
2779                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2780                                 errorf(&expression->base.source_position,
2781                                        "Initialisation expression '%E' is not constant",
2782                                        expression);
2783                         }
2784
2785                         if (type == NULL) {
2786                                 /* we are already outside, ... */
2787                                 type_t *const outer_type_skip = skip_typeref(outer_type);
2788                                 if (is_type_compound(outer_type_skip) &&
2789                                     !outer_type_skip->compound.compound->complete) {
2790                                         goto error_parse_next;
2791                                 }
2792                                 goto error_excess;
2793                         }
2794
2795                         /* handle { "string" } special case */
2796                         if ((expression->kind == EXPR_STRING_LITERAL
2797                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2798                                         && outer_type != NULL) {
2799                                 sub = initializer_from_expression(outer_type, expression);
2800                                 if (sub != NULL) {
2801                                         if (token.type == ',') {
2802                                                 next_token();
2803                                         }
2804                                         if (token.type != '}' && warning.other) {
2805                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2806                                                                  orig_type);
2807                                         }
2808                                         /* TODO: eat , ... */
2809                                         return sub;
2810                                 }
2811                         }
2812
2813                         /* descend into subtypes until expression matches type */
2814                         while (true) {
2815                                 orig_type = path->top_type;
2816                                 type      = skip_typeref(orig_type);
2817
2818                                 sub = initializer_from_expression(orig_type, expression);
2819                                 if (sub != NULL) {
2820                                         break;
2821                                 }
2822                                 if (!is_type_valid(type)) {
2823                                         goto end_error;
2824                                 }
2825                                 if (is_type_scalar(type)) {
2826                                         errorf(&expression->base.source_position,
2827                                                         "expression '%E' doesn't match expected type '%T'",
2828                                                         expression, orig_type);
2829                                         goto end_error;
2830                                 }
2831
2832                                 descend_into_subtype(path);
2833                         }
2834                 }
2835
2836                 /* update largest index of top array */
2837                 const type_path_entry_t *first      = &path->path[0];
2838                 type_t                  *first_type = first->type;
2839                 first_type                          = skip_typeref(first_type);
2840                 if (is_type_array(first_type)) {
2841                         size_t index = first->v.index;
2842                         if (index > path->max_index)
2843                                 path->max_index = index;
2844                 }
2845
2846                 if (type != NULL) {
2847                         /* append to initializers list */
2848                         ARR_APP1(initializer_t*, initializers, sub);
2849                 } else {
2850 error_excess:
2851                         if (warning.other) {
2852                                 if (env->entity != NULL) {
2853                                         warningf(HERE, "excess elements in struct initializer for '%Y'",
2854                                            env->entity->base.symbol);
2855                                 } else {
2856                                         warningf(HERE, "excess elements in struct initializer");
2857                                 }
2858                         }
2859                 }
2860
2861 error_parse_next:
2862                 if (token.type == '}') {
2863                         break;
2864                 }
2865                 expect(',', end_error);
2866                 if (token.type == '}') {
2867                         break;
2868                 }
2869
2870                 if (type != NULL) {
2871                         /* advance to the next declaration if we are not at the end */
2872                         advance_current_object(path, top_path_level);
2873                         orig_type = path->top_type;
2874                         if (orig_type != NULL)
2875                                 type = skip_typeref(orig_type);
2876                         else
2877                                 type = NULL;
2878                 }
2879         }
2880
2881         size_t len  = ARR_LEN(initializers);
2882         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2883         initializer_t *result = allocate_ast_zero(size);
2884         result->kind          = INITIALIZER_LIST;
2885         result->list.len      = len;
2886         memcpy(&result->list.initializers, initializers,
2887                len * sizeof(initializers[0]));
2888
2889         DEL_ARR_F(initializers);
2890         ascend_to(path, top_path_level+1);
2891
2892         return result;
2893
2894 end_error:
2895         skip_initializers();
2896         DEL_ARR_F(initializers);
2897         ascend_to(path, top_path_level+1);
2898         return NULL;
2899 }
2900
2901 /**
2902  * Parses an initializer. Parsers either a compound literal
2903  * (env->declaration == NULL) or an initializer of a declaration.
2904  */
2905 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2906 {
2907         type_t        *type      = skip_typeref(env->type);
2908         size_t         max_index = 0xdeadbeaf;   // TODO: Resolve this uninitialized variable problem
2909         initializer_t *result;
2910
2911         if (is_type_scalar(type)) {
2912                 result = parse_scalar_initializer(type, env->must_be_constant);
2913         } else if (token.type == '{') {
2914                 eat('{');
2915
2916                 type_path_t path;
2917                 memset(&path, 0, sizeof(path));
2918                 path.top_type = env->type;
2919                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2920
2921                 descend_into_subtype(&path);
2922
2923                 add_anchor_token('}');
2924                 result = parse_sub_initializer(&path, env->type, 1, env);
2925                 rem_anchor_token('}');
2926
2927                 max_index = path.max_index;
2928                 DEL_ARR_F(path.path);
2929
2930                 expect('}', end_error);
2931         } else {
2932                 /* parse_scalar_initializer() also works in this case: we simply
2933                  * have an expression without {} around it */
2934                 result = parse_scalar_initializer(type, env->must_be_constant);
2935         }
2936
2937         /* § 6.7.8:22 array initializers for arrays with unknown size determine
2938          * the array type size */
2939         if (is_type_array(type) && type->array.size_expression == NULL
2940                         && result != NULL) {
2941                 size_t size;
2942                 switch (result->kind) {
2943                 case INITIALIZER_LIST:
2944                         assert(max_index != 0xdeadbeaf);
2945                         size = max_index + 1;
2946                         break;
2947
2948                 case INITIALIZER_STRING:
2949                         size = result->string.string.size;
2950                         break;
2951
2952                 case INITIALIZER_WIDE_STRING:
2953                         size = result->wide_string.string.size;
2954                         break;
2955
2956                 case INITIALIZER_DESIGNATOR:
2957                 case INITIALIZER_VALUE:
2958                         /* can happen for parse errors */
2959                         size = 0;
2960                         break;
2961
2962                 default:
2963                         internal_errorf(HERE, "invalid initializer type");
2964                 }
2965
2966                 expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2967                 cnst->base.type          = type_size_t;
2968                 cnst->conste.v.int_value = size;
2969
2970                 type_t *new_type = duplicate_type(type);
2971
2972                 new_type->array.size_expression   = cnst;
2973                 new_type->array.size_constant     = true;
2974                 new_type->array.has_implicit_size = true;
2975                 new_type->array.size              = size;
2976                 env->type = new_type;
2977         }
2978
2979         return result;
2980 end_error:
2981         return NULL;
2982 }
2983
2984 static void append_entity(scope_t *scope, entity_t *entity)
2985 {
2986         if (scope->last_entity != NULL) {
2987                 scope->last_entity->base.next = entity;
2988         } else {
2989                 scope->entities = entity;
2990         }
2991         scope->last_entity = entity;
2992 }
2993
2994
2995 static compound_t *parse_compound_type_specifier(bool is_struct)
2996 {
2997         gnu_attribute_t  *attributes = NULL;
2998         decl_modifiers_t  modifiers  = 0;
2999         if (is_struct) {
3000                 eat(T_struct);
3001         } else {
3002                 eat(T_union);
3003         }
3004
3005         symbol_t   *symbol   = NULL;
3006         compound_t *compound = NULL;
3007
3008         if (token.type == T___attribute__) {
3009                 modifiers |= parse_attributes(&attributes);
3010         }
3011
3012         if (token.type == T_IDENTIFIER) {
3013                 symbol = token.v.symbol;
3014                 next_token();
3015
3016                 namespace_tag_t const namespc =
3017                         is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION;
3018                 entity_t *entity = get_entity(symbol, namespc);
3019                 if (entity != NULL) {
3020                         assert(entity->kind == (is_struct ? ENTITY_STRUCT : ENTITY_UNION));
3021                         compound = &entity->compound;
3022                         if (compound->base.parent_scope != current_scope &&
3023                             (token.type == '{' || token.type == ';')) {
3024                                 /* we're in an inner scope and have a definition. Shadow
3025                                  * existing definition in outer scope */
3026                                 compound = NULL;
3027                         } else if (compound->complete && token.type == '{') {
3028                                 assert(symbol != NULL);
3029                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition %P)",
3030                                        is_struct ? "struct" : "union", symbol,
3031                                        &compound->base.source_position);
3032                                 /* clear members in the hope to avoid further errors */
3033                                 compound->members.entities = NULL;
3034                         }
3035                 }
3036         } else if (token.type != '{') {
3037                 if (is_struct) {
3038                         parse_error_expected("while parsing struct type specifier",
3039                                              T_IDENTIFIER, '{', NULL);
3040                 } else {
3041                         parse_error_expected("while parsing union type specifier",
3042                                              T_IDENTIFIER, '{', NULL);
3043                 }
3044
3045                 return NULL;
3046         }
3047
3048         if (compound == NULL) {
3049                 entity_kind_t  kind   = is_struct ? ENTITY_STRUCT : ENTITY_UNION;
3050                 entity_t      *entity = allocate_entity_zero(kind);
3051                 compound              = &entity->compound;
3052
3053                 compound->base.namespc =
3054                         (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
3055                 compound->base.source_position = token.source_position;
3056                 compound->base.symbol          = symbol;
3057                 compound->base.parent_scope    = current_scope;
3058                 if (symbol != NULL) {
3059                         environment_push(entity);
3060                 }
3061                 append_entity(current_scope, entity);
3062         }
3063
3064         if (token.type == '{') {
3065                 parse_compound_type_entries(compound);
3066                 modifiers |= parse_attributes(&attributes);
3067
3068                 if (symbol == NULL) {
3069                         assert(anonymous_entity == NULL);
3070                         anonymous_entity = (entity_t*)compound;
3071                 }
3072         }
3073
3074         compound->modifiers |= modifiers;
3075         return compound;
3076 }
3077
3078 static void parse_enum_entries(type_t *const enum_type)
3079 {
3080         eat('{');
3081
3082         if (token.type == '}') {
3083                 errorf(HERE, "empty enum not allowed");
3084                 next_token();
3085                 return;
3086         }
3087
3088         add_anchor_token('}');
3089         do {
3090                 if (token.type != T_IDENTIFIER) {
3091                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
3092                         eat_block();
3093                         rem_anchor_token('}');
3094                         return;
3095                 }
3096
3097                 entity_t *entity             = allocate_entity_zero(ENTITY_ENUM_VALUE);
3098                 entity->enum_value.enum_type = enum_type;
3099                 entity->base.symbol          = token.v.symbol;
3100                 entity->base.source_position = token.source_position;
3101                 next_token();
3102
3103                 if (token.type == '=') {
3104                         next_token();
3105                         expression_t *value = parse_constant_expression();
3106
3107                         value = create_implicit_cast(value, enum_type);
3108                         entity->enum_value.value = value;
3109
3110                         /* TODO semantic */
3111                 }
3112
3113                 record_entity(entity, false);
3114
3115                 if (token.type != ',')
3116                         break;
3117                 next_token();
3118         } while (token.type != '}');
3119         rem_anchor_token('}');
3120
3121         expect('}', end_error);
3122
3123 end_error:
3124         ;
3125 }
3126
3127 static type_t *parse_enum_specifier(void)
3128 {
3129         gnu_attribute_t *attributes = NULL;
3130         entity_t        *entity;
3131         symbol_t        *symbol;
3132
3133         eat(T_enum);
3134         if (token.type == T_IDENTIFIER) {
3135                 symbol = token.v.symbol;
3136                 next_token();
3137
3138                 entity = get_entity(symbol, NAMESPACE_ENUM);
3139                 if (entity != NULL) {
3140                         assert(entity->kind == ENTITY_ENUM);
3141                         if (entity->base.parent_scope != current_scope &&
3142                                         (token.type == '{' || token.type == ';')) {
3143                                 /* we're in an inner scope and have a definition. Shadow
3144                                  * existing definition in outer scope */
3145                                 entity = NULL;
3146                         } else if (entity->enume.complete && token.type == '{') {
3147                                 errorf(HERE, "multiple definitions of 'enum %Y' (previous definition %P)",
3148                                                 symbol, &entity->base.source_position);
3149                         }
3150                 }
3151         } else if (token.type != '{') {
3152                 parse_error_expected("while parsing enum type specifier",
3153                                      T_IDENTIFIER, '{', NULL);
3154                 return NULL;
3155         } else {
3156                 entity  = NULL;
3157                 symbol  = NULL;
3158         }
3159
3160         if (entity == NULL) {
3161                 entity                       = allocate_entity_zero(ENTITY_ENUM);
3162                 entity->base.namespc         = NAMESPACE_ENUM;
3163                 entity->base.source_position = token.source_position;
3164                 entity->base.symbol          = symbol;
3165                 entity->base.parent_scope    = current_scope;
3166         }
3167
3168         type_t *const type = allocate_type_zero(TYPE_ENUM);
3169         type->enumt.enume  = &entity->enume;
3170
3171         if (token.type == '{') {
3172                 if (symbol != NULL) {
3173                         environment_push(entity);
3174                 }
3175                 append_entity(current_scope, entity);
3176                 entity->enume.complete = true;
3177
3178                 parse_enum_entries(type);
3179                 parse_attributes(&attributes);
3180
3181                 if (symbol == NULL) {
3182                         assert(anonymous_entity == NULL);
3183                         anonymous_entity = entity;
3184                 }
3185         } else if (!entity->enume.complete && !(c_mode & _GNUC)) {
3186                 errorf(HERE, "'enum %Y' used before definition (incomplete enums are a GNU extension)",
3187                        symbol);
3188         }
3189
3190         return type;
3191 }
3192
3193 /**
3194  * if a symbol is a typedef to another type, return true
3195  */
3196 static bool is_typedef_symbol(symbol_t *symbol)
3197 {
3198         const entity_t *const entity = get_entity(symbol, NAMESPACE_NORMAL);
3199         return entity != NULL && entity->kind == ENTITY_TYPEDEF;
3200 }
3201
3202 static type_t *parse_typeof(void)
3203 {
3204         eat(T___typeof__);
3205
3206         type_t *type;
3207
3208         expect('(', end_error);
3209         add_anchor_token(')');
3210
3211         expression_t *expression  = NULL;
3212
3213         bool old_type_prop     = in_type_prop;
3214         bool old_gcc_extension = in_gcc_extension;
3215         in_type_prop           = true;
3216
3217         while (token.type == T___extension__) {
3218                 /* This can be a prefix to a typename or an expression. */
3219                 next_token();
3220                 in_gcc_extension = true;
3221         }
3222         switch (token.type) {
3223         case T_IDENTIFIER:
3224                 if (is_typedef_symbol(token.v.symbol)) {
3225                         type = parse_typename();
3226                 } else {
3227                         expression = parse_expression();
3228                         type       = expression->base.type;
3229                 }
3230                 break;
3231
3232         TYPENAME_START
3233                 type = parse_typename();
3234                 break;
3235
3236         default:
3237                 expression = parse_expression();
3238                 type       = expression->base.type;
3239                 break;
3240         }
3241         in_type_prop     = old_type_prop;
3242         in_gcc_extension = old_gcc_extension;
3243
3244         rem_anchor_token(')');
3245         expect(')', end_error);
3246
3247         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF);
3248         typeof_type->typeoft.expression  = expression;
3249         typeof_type->typeoft.typeof_type = type;
3250
3251         return typeof_type;
3252 end_error:
3253         return NULL;
3254 }
3255
3256 typedef enum specifiers_t {
3257         SPECIFIER_SIGNED    = 1 << 0,
3258         SPECIFIER_UNSIGNED  = 1 << 1,
3259         SPECIFIER_LONG      = 1 << 2,
3260         SPECIFIER_INT       = 1 << 3,
3261         SPECIFIER_DOUBLE    = 1 << 4,
3262         SPECIFIER_CHAR      = 1 << 5,
3263         SPECIFIER_WCHAR_T   = 1 << 6,
3264         SPECIFIER_SHORT     = 1 << 7,
3265         SPECIFIER_LONG_LONG = 1 << 8,
3266         SPECIFIER_FLOAT     = 1 << 9,
3267         SPECIFIER_BOOL      = 1 << 10,
3268         SPECIFIER_VOID      = 1 << 11,
3269         SPECIFIER_INT8      = 1 << 12,
3270         SPECIFIER_INT16     = 1 << 13,
3271         SPECIFIER_INT32     = 1 << 14,
3272         SPECIFIER_INT64     = 1 << 15,
3273         SPECIFIER_INT128    = 1 << 16,
3274         SPECIFIER_COMPLEX   = 1 << 17,
3275         SPECIFIER_IMAGINARY = 1 << 18,
3276 } specifiers_t;
3277
3278 static type_t *create_builtin_type(symbol_t *const symbol,
3279                                    type_t *const real_type)
3280 {
3281         type_t *type            = allocate_type_zero(TYPE_BUILTIN);
3282         type->builtin.symbol    = symbol;
3283         type->builtin.real_type = real_type;
3284         return identify_new_type(type);
3285 }
3286
3287 static type_t *get_typedef_type(symbol_t *symbol)
3288 {
3289         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
3290         if (entity == NULL || entity->kind != ENTITY_TYPEDEF)
3291                 return NULL;
3292
3293         type_t *type            = allocate_type_zero(TYPE_TYPEDEF);
3294         type->typedeft.typedefe = &entity->typedefe;
3295
3296         return type;
3297 }
3298
3299 /**
3300  * check for the allowed MS alignment values.
3301  */
3302 static bool check_alignment_value(long long intvalue)
3303 {
3304         if (intvalue < 1 || intvalue > 8192) {
3305                 errorf(HERE, "illegal alignment value");
3306                 return false;
3307         }
3308         unsigned v = (unsigned)intvalue;
3309         for (unsigned i = 1; i <= 8192; i += i) {
3310                 if (i == v)
3311                         return true;
3312         }
3313         errorf(HERE, "alignment must be power of two");
3314         return false;
3315 }
3316
3317 #define DET_MOD(name, tag) do { \
3318         if (*modifiers & tag && warning.other) warningf(HERE, #name " used more than once"); \
3319         *modifiers |= tag; \
3320 } while (0)
3321
3322 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
3323 {
3324         decl_modifiers_t *modifiers = &specifiers->modifiers;
3325
3326         while (true) {
3327                 if (token.type == T_restrict) {
3328                         next_token();
3329                         DET_MOD(restrict, DM_RESTRICT);
3330                         goto end_loop;
3331                 } else if (token.type != T_IDENTIFIER)
3332                         break;
3333                 symbol_t *symbol = token.v.symbol;
3334                 if (symbol == sym_align) {
3335                         next_token();
3336                         expect('(', end_error);
3337                         if (token.type != T_INTEGER)
3338                                 goto end_error;
3339                         if (check_alignment_value(token.v.intvalue)) {
3340                                 if (specifiers->alignment != 0 && warning.other)
3341                                         warningf(HERE, "align used more than once");
3342                                 specifiers->alignment = (unsigned char)token.v.intvalue;
3343                         }
3344                         next_token();
3345                         expect(')', end_error);
3346                 } else if (symbol == sym_allocate) {
3347                         next_token();
3348                         expect('(', end_error);
3349                         if (token.type != T_IDENTIFIER)
3350                                 goto end_error;
3351                         (void)token.v.symbol;
3352                         expect(')', end_error);
3353                 } else if (symbol == sym_dllimport) {
3354                         next_token();
3355                         DET_MOD(dllimport, DM_DLLIMPORT);
3356                 } else if (symbol == sym_dllexport) {
3357                         next_token();
3358                         DET_MOD(dllexport, DM_DLLEXPORT);
3359                 } else if (symbol == sym_thread) {
3360                         next_token();
3361                         DET_MOD(thread, DM_THREAD);
3362                 } else if (symbol == sym_naked) {
3363                         next_token();
3364                         DET_MOD(naked, DM_NAKED);
3365                 } else if (symbol == sym_noinline) {
3366                         next_token();
3367                         DET_MOD(noinline, DM_NOINLINE);
3368                 } else if (symbol == sym_returns_twice) {
3369                         next_token();
3370                         DET_MOD(returns_twice, DM_RETURNS_TWICE);
3371                 } else if (symbol == sym_noreturn) {
3372                         next_token();
3373                         DET_MOD(noreturn, DM_NORETURN);
3374                 } else if (symbol == sym_nothrow) {
3375                         next_token();
3376                         DET_MOD(nothrow, DM_NOTHROW);
3377                 } else if (symbol == sym_novtable) {
3378                         next_token();
3379                         DET_MOD(novtable, DM_NOVTABLE);
3380                 } else if (symbol == sym_property) {
3381                         next_token();
3382                         expect('(', end_error);
3383                         for (;;) {
3384                                 bool is_get = false;
3385                                 if (token.type != T_IDENTIFIER)
3386                                         goto end_error;
3387                                 if (token.v.symbol == sym_get) {
3388                                         is_get = true;
3389                                 } else if (token.v.symbol == sym_put) {
3390                                 } else {
3391                                         errorf(HERE, "Bad property name '%Y'", token.v.symbol);
3392                                         goto end_error;
3393                                 }
3394                                 next_token();
3395                                 expect('=', end_error);
3396                                 if (token.type != T_IDENTIFIER)
3397                                         goto end_error;
3398                                 if (is_get) {
3399                                         if (specifiers->get_property_sym != NULL) {
3400                                                 errorf(HERE, "get property name already specified");
3401                                         } else {
3402                                                 specifiers->get_property_sym = token.v.symbol;
3403                                         }
3404                                 } else {
3405                                         if (specifiers->put_property_sym != NULL) {
3406                                                 errorf(HERE, "put property name already specified");
3407                                         } else {
3408                                                 specifiers->put_property_sym = token.v.symbol;
3409                                         }
3410                                 }
3411                                 next_token();
3412                                 if (token.type == ',') {
3413                                         next_token();
3414                                         continue;
3415                                 }
3416                                 break;
3417                         }
3418                         expect(')', end_error);
3419                 } else if (symbol == sym_selectany) {
3420                         next_token();
3421                         DET_MOD(selectany, DM_SELECTANY);
3422                 } else if (symbol == sym_uuid) {
3423                         next_token();
3424                         expect('(', end_error);
3425                         if (token.type != T_STRING_LITERAL)
3426                                 goto end_error;
3427                         next_token();
3428                         expect(')', end_error);
3429                 } else if (symbol == sym_deprecated) {
3430                         next_token();
3431                         if (specifiers->deprecated != 0 && warning.other)
3432                                 warningf(HERE, "deprecated used more than once");
3433                         specifiers->deprecated = true;
3434                         if (token.type == '(') {
3435                                 next_token();
3436                                 if (token.type == T_STRING_LITERAL) {
3437                                         specifiers->deprecated_string = token.v.string.begin;
3438                                         next_token();
3439                                 } else {
3440                                         errorf(HERE, "string literal expected");
3441                                 }
3442                                 expect(')', end_error);
3443                         }
3444                 } else if (symbol == sym_noalias) {
3445                         next_token();
3446                         DET_MOD(noalias, DM_NOALIAS);
3447                 } else {
3448                         if (warning.other)
3449                                 warningf(HERE, "Unknown modifier '%Y' ignored", token.v.symbol);
3450                         next_token();
3451                         if (token.type == '(')
3452                                 skip_until(')');
3453                 }
3454 end_loop:
3455                 if (token.type == ',')
3456                         next_token();
3457         }
3458 end_error:
3459         return;
3460 }
3461
3462 static entity_t *create_error_entity(symbol_t *symbol, entity_kind_tag_t kind)
3463 {
3464         entity_t *entity             = allocate_entity_zero(kind);
3465         entity->base.source_position = *HERE;
3466         entity->base.symbol          = symbol;
3467         if (is_declaration(entity)) {
3468                 entity->declaration.type     = type_error_type;
3469                 entity->declaration.implicit = true;
3470         } else if (kind == ENTITY_TYPEDEF) {
3471                 entity->typedefe.type    = type_error_type;
3472                 entity->typedefe.builtin = true;
3473         }
3474         if (kind != ENTITY_COMPOUND_MEMBER)
3475                 record_entity(entity, false);
3476         return entity;
3477 }
3478
3479 static void parse_microsoft_based(based_spec_t *based_spec)
3480 {
3481         if (token.type != T_IDENTIFIER) {
3482                 parse_error_expected("while parsing __based", T_IDENTIFIER, NULL);
3483                 return;
3484         }
3485         symbol_t *symbol = token.v.symbol;
3486         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
3487
3488         if (entity == NULL || entity->base.kind != ENTITY_VARIABLE) {
3489                 errorf(HERE, "'%Y' is not a variable name.", symbol);
3490                 entity = create_error_entity(symbol, ENTITY_VARIABLE);
3491         } else {
3492                 variable_t *variable = &entity->variable;
3493
3494                 if (based_spec->base_variable != NULL) {
3495                         errorf(HERE, "__based type qualifier specified more than once");
3496                 }
3497                 based_spec->source_position = token.source_position;
3498                 based_spec->base_variable   = variable;
3499
3500                 type_t *const type = variable->base.type;
3501
3502                 if (is_type_valid(type)) {
3503                         if (! is_type_pointer(skip_typeref(type))) {
3504                                 errorf(HERE, "variable in __based modifier must have pointer type instead of '%T'", type);
3505                         }
3506                         if (variable->base.base.parent_scope != file_scope) {
3507                                 errorf(HERE, "a nonstatic local variable may not be used in a __based specification");
3508                         }
3509                 }
3510         }
3511         next_token();
3512 }
3513
3514 /**
3515  * Finish the construction of a struct type by calculating
3516  * its size, offsets, alignment.
3517  */
3518 static void finish_struct_type(compound_type_t *type)
3519 {
3520         assert(type->compound != NULL);
3521
3522         compound_t *compound = type->compound;
3523         if (!compound->complete)
3524                 return;
3525
3526         il_size_t      size           = 0;
3527         il_size_t      offset;
3528         il_alignment_t alignment      = 1;
3529         bool           need_pad       = false;
3530
3531         entity_t *entry = compound->members.entities;
3532         for (; entry != NULL; entry = entry->base.next) {
3533                 if (entry->kind != ENTITY_COMPOUND_MEMBER)
3534                         continue;
3535
3536                 type_t *m_type = skip_typeref(entry->declaration.type);
3537                 if (! is_type_valid(m_type)) {
3538                         /* simply ignore errors here */
3539                         continue;
3540                 }
3541                 il_alignment_t m_alignment = m_type->base.alignment;
3542                 if (m_alignment > alignment)
3543                         alignment = m_alignment;
3544
3545                 offset = (size + m_alignment - 1) & -m_alignment;
3546
3547                 if (offset > size)
3548                         need_pad = true;
3549                 entry->compound_member.offset = offset;
3550                 size = offset + m_type->base.size;
3551         }
3552         if (type->base.alignment != 0) {
3553                 alignment = type->base.alignment;
3554         }
3555
3556         offset = (size + alignment - 1) & -alignment;
3557         if (offset > size)
3558                 need_pad = true;
3559
3560         if (need_pad) {
3561                 if (warning.padded) {
3562                         warningf(&compound->base.source_position, "'%T' needs padding", type);
3563                 }
3564         } else {
3565                 if (compound->modifiers & DM_PACKED && warning.packed) {
3566                         warningf(&compound->base.source_position,
3567                                         "superfluous packed attribute on '%T'", type);
3568                 }
3569         }
3570
3571         type->base.size      = offset;
3572         type->base.alignment = alignment;
3573 }
3574
3575 /**
3576  * Finish the construction of an union type by calculating
3577  * its size and alignment.
3578  */
3579 static void finish_union_type(compound_type_t *type)
3580 {
3581         assert(type->compound != NULL);
3582
3583         compound_t *compound = type->compound;
3584         if (! compound->complete)
3585                 return;
3586
3587         il_size_t      size      = 0;
3588         il_alignment_t alignment = 1;
3589
3590         entity_t *entry = compound->members.entities;
3591         for (; entry != NULL; entry = entry->base.next) {
3592                 if (entry->kind != ENTITY_COMPOUND_MEMBER)
3593                         continue;
3594
3595                 type_t *m_type = skip_typeref(entry->declaration.type);
3596                 if (! is_type_valid(m_type))
3597                         continue;
3598
3599                 entry->compound_member.offset = 0;
3600                 if (m_type->base.size > size)
3601                         size = m_type->base.size;
3602                 if (m_type->base.alignment > alignment)
3603                         alignment = m_type->base.alignment;
3604         }
3605         if (type->base.alignment != 0) {
3606                 alignment = type->base.alignment;
3607         }
3608         size = (size + alignment - 1) & -alignment;
3609         type->base.size      = size;
3610         type->base.alignment = alignment;
3611 }
3612
3613 static type_t *handle_mode_attribute(const gnu_attribute_t *attribute,
3614                                      type_t *orig_type)
3615 {
3616         type_t *type = skip_typeref(orig_type);
3617         if (type->kind != TYPE_ATOMIC) {
3618                 errorf(HERE,
3619                            "__attribute__(mode)) only allowed for atomic types");
3620                 return orig_type;
3621         }
3622         atomic_type_kind_t  akind = attribute->u.akind;
3623         if (!is_type_signed(type)) {
3624                 switch (akind) {
3625                 case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
3626                 case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
3627                 case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
3628                 case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
3629                 default:
3630                         errorf(HERE, "invalid akind in mode attribute");
3631                         return orig_type;
3632                 }
3633         } else {
3634                 switch (akind) {
3635                 case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_SCHAR; break;
3636                 case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_SHORT; break;
3637                 case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_INT; break;
3638                 case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_LONGLONG; break;
3639                 default:
3640                         errorf(HERE, "invalid akind in mode attribute");
3641                         return orig_type;
3642                 }
3643         }
3644
3645         type_t *copy       = duplicate_type(type);
3646         copy->atomic.akind = akind;
3647         return identify_new_type(copy);
3648 }
3649
3650 static type_t *handle_type_attributes(const gnu_attribute_t *attributes,
3651                                       type_t *type)
3652 {
3653         /* handle these strange/stupid mode attributes */
3654         const gnu_attribute_t *attribute = attributes;
3655         for ( ; attribute != NULL; attribute = attribute->next) {
3656                 if (attribute->invalid)
3657                         continue;
3658
3659                 if (attribute->kind == GNU_AK_MODE) {
3660                         type = handle_mode_attribute(attribute, type);
3661                 } else if (attribute->kind == GNU_AK_ALIGNED) {
3662                         int alignment = 32; /* TODO: fill in maximum useful alignment for
3663                                                target machine */
3664                         if (attribute->has_arguments)
3665                                 alignment = attribute->u.argument;
3666
3667                         type_t *copy         = duplicate_type(type);
3668                         copy->base.alignment = attribute->u.argument;
3669                         type                 = identify_new_type(copy);
3670                 }
3671         }
3672
3673         return type;
3674 }
3675
3676 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
3677 {
3678         type_t            *type              = NULL;
3679         type_qualifiers_t  qualifiers        = TYPE_QUALIFIER_NONE;
3680         type_modifiers_t   modifiers         = TYPE_MODIFIER_NONE;
3681         unsigned           type_specifiers   = 0;
3682         bool               newtype           = false;
3683         bool               saw_error         = false;
3684         bool               old_gcc_extension = in_gcc_extension;
3685
3686         specifiers->source_position = token.source_position;
3687
3688         while (true) {
3689                 specifiers->modifiers
3690                         |= parse_attributes(&specifiers->gnu_attributes);
3691
3692                 switch (token.type) {
3693                 /* storage class */
3694 #define MATCH_STORAGE_CLASS(token, class)                                  \
3695                 case token:                                                        \
3696                         if (specifiers->storage_class != STORAGE_CLASS_NONE) {         \
3697                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3698                         }                                                              \
3699                         specifiers->storage_class = class;                             \
3700                         if (specifiers->thread_local)                                  \
3701                                 goto check_thread_storage_class;                           \
3702                         next_token();                                                  \
3703                         break;
3704
3705                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3706                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3707                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3708                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3709                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3710
3711                 case T__declspec:
3712                         next_token();
3713                         expect('(', end_error);
3714                         add_anchor_token(')');
3715                         parse_microsoft_extended_decl_modifier(specifiers);
3716                         rem_anchor_token(')');
3717                         expect(')', end_error);
3718                         break;
3719
3720                 case T___thread:
3721                         if (specifiers->thread_local) {
3722                                 errorf(HERE, "duplicate '__thread'");
3723                         } else {
3724                                 specifiers->thread_local = true;
3725 check_thread_storage_class:
3726                                 switch (specifiers->storage_class) {
3727                                         case STORAGE_CLASS_EXTERN:
3728                                         case STORAGE_CLASS_NONE:
3729                                         case STORAGE_CLASS_STATIC:
3730                                                 break;
3731
3732                                                 char const* wrong;
3733                                         case STORAGE_CLASS_AUTO:     wrong = "auto";     goto wrong_thread_stoarge_class;
3734                                         case STORAGE_CLASS_REGISTER: wrong = "register"; goto wrong_thread_stoarge_class;
3735                                         case STORAGE_CLASS_TYPEDEF:  wrong = "typedef";  goto wrong_thread_stoarge_class;
3736 wrong_thread_stoarge_class:
3737                                                 errorf(HERE, "'__thread' used with '%s'", wrong);
3738                                                 break;
3739                                 }
3740                         }
3741                         next_token();
3742                         break;
3743
3744                 /* type qualifiers */
3745 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3746                 case token:                                                     \
3747                         qualifiers |= qualifier;                                    \
3748                         next_token();                                               \
3749                         break
3750
3751                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3752                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3753                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3754                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3755                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3756                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3757                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3758                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3759
3760                 case T___extension__:
3761                         next_token();
3762                         in_gcc_extension = true;
3763                         break;
3764
3765                 /* type specifiers */
3766 #define MATCH_SPECIFIER(token, specifier, name)                         \
3767                 case token:                                                     \
3768                         if (type_specifiers & specifier) {                           \
3769                                 errorf(HERE, "multiple " name " type specifiers given"); \
3770                         } else {                                                    \
3771                                 type_specifiers |= specifier;                           \
3772                         }                                                           \
3773                         next_token();                                               \
3774                         break
3775
3776                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3777                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3778                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3779                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3780                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3781                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3782                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3783                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3784                 MATCH_SPECIFIER(T_bool,       SPECIFIER_BOOL,      "bool");
3785                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3786                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3787                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3788                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3789                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3790                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3791                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3792                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3793                 MATCH_SPECIFIER(T_wchar_t,    SPECIFIER_WCHAR_T,   "wchar_t");
3794
3795                 case T__forceinline:
3796                         /* only in microsoft mode */
3797                         specifiers->modifiers |= DM_FORCEINLINE;
3798                         /* FALLTHROUGH */
3799
3800                 case T_inline:
3801                         next_token();
3802                         specifiers->is_inline = true;
3803                         break;
3804
3805                 case T_long:
3806                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3807                                 errorf(HERE, "multiple type specifiers given");
3808                         } else if (type_specifiers & SPECIFIER_LONG) {
3809                                 type_specifiers |= SPECIFIER_LONG_LONG;
3810                         } else {
3811                                 type_specifiers |= SPECIFIER_LONG;
3812                         }
3813                         next_token();
3814                         break;
3815
3816                 case T_struct: {
3817                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT);
3818
3819                         type->compound.compound = parse_compound_type_specifier(true);
3820                         finish_struct_type(&type->compound);
3821                         break;
3822                 }
3823                 case T_union: {
3824                         type = allocate_type_zero(TYPE_COMPOUND_UNION);
3825                         type->compound.compound = parse_compound_type_specifier(false);
3826                         if (type->compound.compound->modifiers & DM_TRANSPARENT_UNION)
3827                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3828                         finish_union_type(&type->compound);
3829                         break;
3830                 }
3831                 case T_enum:
3832                         type = parse_enum_specifier();
3833                         break;
3834                 case T___typeof__:
3835                         type = parse_typeof();
3836                         break;
3837                 case T___builtin_va_list:
3838                         type = duplicate_type(type_valist);
3839                         next_token();
3840                         break;
3841
3842                 case T_IDENTIFIER: {
3843                         /* only parse identifier if we haven't found a type yet */
3844                         if (type != NULL || type_specifiers != 0) {
3845                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
3846                                  * declaration, so it doesn't generate errors about expecting '(' or
3847                                  * '{' later on. */
3848                                 switch (look_ahead(1)->type) {
3849                                         STORAGE_CLASSES
3850                                         TYPE_SPECIFIERS
3851                                         case T_const:
3852                                         case T_restrict:
3853                                         case T_volatile:
3854                                         case T_inline:
3855                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
3856                                         case T_IDENTIFIER:
3857                                         case '&':
3858                                         case '*':
3859                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
3860                                                 next_token();
3861                                                 continue;
3862
3863                                         default:
3864                                                 goto finish_specifiers;
3865                                 }
3866                         }
3867
3868                         type_t *const typedef_type = get_typedef_type(token.v.symbol);
3869                         if (typedef_type == NULL) {
3870                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3871                                  * declaration, so it doesn't generate 'implicit int' followed by more
3872                                  * errors later on. */
3873                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3874                                 switch (la1_type) {
3875                                         DECLARATION_START
3876                                         case T_IDENTIFIER:
3877                                         case '&':
3878                                         case '*': {
3879                                                 errorf(HERE, "%K does not name a type", &token);
3880
3881                                                 entity_t *entity =
3882                                                         create_error_entity(token.v.symbol, ENTITY_TYPEDEF);
3883
3884                                                 type = allocate_type_zero(TYPE_TYPEDEF);
3885                                                 type->typedeft.typedefe = &entity->typedefe;
3886
3887                                                 next_token();
3888                                                 saw_error = true;
3889                                                 if (la1_type == '&' || la1_type == '*')
3890                                                         goto finish_specifiers;
3891                                                 continue;
3892                                         }
3893
3894                                         default:
3895                                                 goto finish_specifiers;
3896                                 }
3897                         }
3898
3899                         next_token();
3900                         type = typedef_type;
3901                         break;
3902                 }
3903
3904                 /* function specifier */
3905                 default:
3906                         goto finish_specifiers;
3907                 }
3908         }
3909
3910 finish_specifiers:
3911         specifiers->modifiers
3912                 |= parse_attributes(&specifiers->gnu_attributes);
3913
3914         in_gcc_extension = old_gcc_extension;
3915
3916         if (type == NULL || (saw_error && type_specifiers != 0)) {
3917                 atomic_type_kind_t atomic_type;
3918
3919                 /* match valid basic types */
3920                 switch (type_specifiers) {
3921                 case SPECIFIER_VOID:
3922                         atomic_type = ATOMIC_TYPE_VOID;
3923                         break;
3924                 case SPECIFIER_WCHAR_T:
3925                         atomic_type = ATOMIC_TYPE_WCHAR_T;
3926                         break;
3927                 case SPECIFIER_CHAR:
3928                         atomic_type = ATOMIC_TYPE_CHAR;
3929                         break;
3930                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3931                         atomic_type = ATOMIC_TYPE_SCHAR;
3932                         break;
3933                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3934                         atomic_type = ATOMIC_TYPE_UCHAR;
3935                         break;
3936                 case SPECIFIER_SHORT:
3937                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3938                 case SPECIFIER_SHORT | SPECIFIER_INT:
3939                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3940                         atomic_type = ATOMIC_TYPE_SHORT;
3941                         break;
3942                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3943                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3944                         atomic_type = ATOMIC_TYPE_USHORT;
3945                         break;
3946                 case SPECIFIER_INT:
3947                 case SPECIFIER_SIGNED:
3948                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3949                         atomic_type = ATOMIC_TYPE_INT;
3950                         break;
3951                 case SPECIFIER_UNSIGNED:
3952                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3953                         atomic_type = ATOMIC_TYPE_UINT;
3954                         break;
3955                 case SPECIFIER_LONG:
3956                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3957                 case SPECIFIER_LONG | SPECIFIER_INT:
3958                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3959                         atomic_type = ATOMIC_TYPE_LONG;
3960                         break;
3961                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3962                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3963                         atomic_type = ATOMIC_TYPE_ULONG;
3964                         break;
3965
3966                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3967                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3968                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3969                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3970                         | SPECIFIER_INT:
3971                         atomic_type = ATOMIC_TYPE_LONGLONG;
3972                         goto warn_about_long_long;
3973
3974                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3975                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3976                         | SPECIFIER_INT:
3977                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3978 warn_about_long_long:
3979                         if (warning.long_long) {
3980                                 warningf(&specifiers->source_position,
3981                                          "ISO C90 does not support 'long long'");
3982                         }
3983                         break;
3984
3985                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3986                         atomic_type = unsigned_int8_type_kind;
3987                         break;
3988
3989                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3990                         atomic_type = unsigned_int16_type_kind;
3991                         break;
3992
3993                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3994                         atomic_type = unsigned_int32_type_kind;
3995                         break;
3996
3997                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3998                         atomic_type = unsigned_int64_type_kind;
3999                         break;
4000
4001                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
4002                         atomic_type = unsigned_int128_type_kind;
4003                         break;
4004
4005                 case SPECIFIER_INT8:
4006                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
4007                         atomic_type = int8_type_kind;
4008                         break;
4009
4010                 case SPECIFIER_INT16:
4011                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
4012                         atomic_type = int16_type_kind;
4013                         break;
4014
4015                 case SPECIFIER_INT32:
4016                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
4017                         atomic_type = int32_type_kind;
4018                         break;
4019
4020                 case SPECIFIER_INT64:
4021                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
4022                         atomic_type = int64_type_kind;
4023                         break;
4024
4025                 case SPECIFIER_INT128:
4026                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
4027                         atomic_type = int128_type_kind;
4028                         break;
4029
4030                 case SPECIFIER_FLOAT:
4031                         atomic_type = ATOMIC_TYPE_FLOAT;
4032                         break;
4033                 case SPECIFIER_DOUBLE:
4034                         atomic_type = ATOMIC_TYPE_DOUBLE;
4035                         break;
4036                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
4037                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
4038                         break;
4039                 case SPECIFIER_BOOL:
4040                         atomic_type = ATOMIC_TYPE_BOOL;
4041                         break;
4042                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
4043                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
4044                         atomic_type = ATOMIC_TYPE_FLOAT;
4045                         break;
4046                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
4047                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
4048                         atomic_type = ATOMIC_TYPE_DOUBLE;
4049                         break;
4050                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
4051                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
4052                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
4053                         break;
4054                 default:
4055                         /* invalid specifier combination, give an error message */
4056                         if (type_specifiers == 0) {
4057                                 if (saw_error)
4058                                         goto end_error;
4059
4060                                 /* ISO/IEC 14882:1998(E) §C.1.5:4 */
4061                                 if (!(c_mode & _CXX) && !strict_mode) {
4062                                         if (warning.implicit_int) {
4063                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
4064                                         }
4065                                         atomic_type = ATOMIC_TYPE_INT;
4066                                         break;
4067                                 } else {
4068                                         errorf(HERE, "no type specifiers given in declaration");
4069                                 }
4070                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
4071                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
4072                                 errorf(HERE, "signed and unsigned specifiers given");
4073                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
4074                                 errorf(HERE, "only integer types can be signed or unsigned");
4075                         } else {
4076                                 errorf(HERE, "multiple datatypes in declaration");
4077                         }
4078                         goto end_error;
4079                 }
4080
4081                 if (type_specifiers & SPECIFIER_COMPLEX) {
4082                         type                = allocate_type_zero(TYPE_COMPLEX);
4083                         type->complex.akind = atomic_type;
4084                 } else if (type_specifiers & SPECIFIER_IMAGINARY) {
4085                         type                  = allocate_type_zero(TYPE_IMAGINARY);
4086                         type->imaginary.akind = atomic_type;
4087                 } else {
4088                         type                 = allocate_type_zero(TYPE_ATOMIC);
4089                         type->atomic.akind   = atomic_type;
4090                 }
4091                 type->base.alignment = get_atomic_type_alignment(atomic_type);
4092                 unsigned const size  = get_atomic_type_size(atomic_type);
4093                 type->base.size      =
4094                         type_specifiers & SPECIFIER_COMPLEX ? size * 2 : size;
4095                 newtype = true;
4096         } else if (type_specifiers != 0) {
4097                 errorf(HERE, "multiple datatypes in declaration");
4098         }
4099
4100         /* FIXME: check type qualifiers here */
4101
4102         if (specifiers->modifiers & DM_TRANSPARENT_UNION)
4103                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
4104         type->base.qualifiers = qualifiers;
4105         type->base.modifiers  = modifiers;
4106
4107         type = identify_new_type(type);
4108
4109         type = handle_type_attributes(specifiers->gnu_attributes, type);
4110         specifiers->type = type;
4111         return;
4112
4113 end_error:
4114         specifiers->type = type_error_type;
4115         return;
4116 }
4117
4118 static type_qualifiers_t parse_type_qualifiers(void)
4119 {
4120         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
4121
4122         while (true) {
4123                 switch (token.type) {
4124                 /* type qualifiers */
4125                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
4126                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
4127                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
4128                 /* microsoft extended type modifiers */
4129                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
4130                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
4131                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
4132                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
4133                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
4134
4135                 default:
4136                         return qualifiers;
4137                 }
4138         }
4139 }
4140
4141 /**
4142  * Parses an K&R identifier list
4143  */
4144 static void parse_identifier_list(scope_t *scope)
4145 {
4146         do {
4147                 entity_t *entity = allocate_entity_zero(ENTITY_PARAMETER);
4148                 entity->base.source_position = token.source_position;
4149                 entity->base.namespc         = NAMESPACE_NORMAL;
4150                 entity->base.symbol          = token.v.symbol;
4151                 /* a K&R parameter has no type, yet */
4152                 next_token();
4153
4154                 if (scope != NULL)
4155                         append_entity(scope, entity);
4156
4157                 if (token.type != ',') {
4158                         break;
4159                 }
4160                 next_token();
4161         } while (token.type == T_IDENTIFIER);
4162 }
4163
4164 static entity_t *parse_parameter(void)
4165 {
4166         declaration_specifiers_t specifiers;
4167         memset(&specifiers, 0, sizeof(specifiers));
4168
4169         parse_declaration_specifiers(&specifiers);
4170
4171         entity_t *entity = parse_declarator(&specifiers,
4172                         DECL_MAY_BE_ABSTRACT | DECL_IS_PARAMETER);
4173         anonymous_entity = NULL;
4174         return entity;
4175 }
4176
4177 static void semantic_parameter_incomplete(const entity_t *entity)
4178 {
4179         assert(entity->kind == ENTITY_PARAMETER);
4180
4181         /* §6.7.5.3:4  After adjustment, the parameters in a parameter type
4182          *             list in a function declarator that is part of a
4183          *             definition of that function shall not have
4184          *             incomplete type. */
4185         type_t *type = skip_typeref(entity->declaration.type);
4186         if (is_type_incomplete(type)) {
4187                 errorf(&entity->base.source_position,
4188                        "parameter '%Y' has incomplete type '%T'", entity->base.symbol,
4189                        entity->declaration.type);
4190         }
4191 }
4192
4193 /**
4194  * Parses function type parameters (and optionally creates variable_t entities
4195  * for them in a scope)
4196  */
4197 static void parse_parameters(function_type_t *type, scope_t *scope)
4198 {
4199         eat('(');
4200         add_anchor_token(')');
4201         int saved_comma_state = save_and_reset_anchor_state(',');
4202
4203         if (token.type == T_IDENTIFIER &&
4204             !is_typedef_symbol(token.v.symbol)) {
4205                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
4206                 if (la1_type == ',' || la1_type == ')') {
4207                         type->kr_style_parameters    = true;
4208                         type->unspecified_parameters = true;
4209                         parse_identifier_list(scope);
4210                         goto parameters_finished;
4211                 }
4212         }
4213
4214         if (token.type == ')') {
4215                 /* ISO/IEC 14882:1998(E) §C.1.6:1 */
4216                 if (!(c_mode & _CXX))
4217                         type->unspecified_parameters = true;
4218                 goto parameters_finished;
4219         }
4220
4221         function_parameter_t *parameter;
4222         function_parameter_t *last_parameter = NULL;
4223
4224         while (true) {
4225                 switch (token.type) {
4226                 case T_DOTDOTDOT:
4227                         next_token();
4228                         type->variadic = true;
4229                         goto parameters_finished;
4230
4231                 case T_IDENTIFIER:
4232                 case T___extension__:
4233                 DECLARATION_START
4234                 {
4235                         entity_t *entity = parse_parameter();
4236                         if (entity->kind == ENTITY_TYPEDEF) {
4237                                 errorf(&entity->base.source_position,
4238                                        "typedef not allowed as function parameter");
4239                                 break;
4240                         }
4241                         assert(is_declaration(entity));
4242
4243                         /* func(void) is not a parameter */
4244                         if (last_parameter == NULL
4245                                         && token.type == ')'
4246                                         && entity->base.symbol == NULL
4247                                         && skip_typeref(entity->declaration.type) == type_void) {
4248                                 goto parameters_finished;
4249                         }
4250                         semantic_parameter_incomplete(entity);
4251
4252                         parameter = obstack_alloc(type_obst, sizeof(parameter[0]));
4253                         memset(parameter, 0, sizeof(parameter[0]));
4254                         parameter->type = entity->declaration.type;
4255
4256                         if (scope != NULL) {
4257                                 append_entity(scope, entity);
4258                         }
4259
4260                         if (last_parameter != NULL) {
4261                                 last_parameter->next = parameter;
4262                         } else {
4263                                 type->parameters = parameter;
4264                         }
4265                         last_parameter   = parameter;
4266                         break;
4267                 }
4268
4269                 default:
4270                         goto parameters_finished;
4271                 }
4272                 if (token.type != ',') {
4273                         goto parameters_finished;
4274                 }
4275                 next_token();
4276         }
4277
4278
4279 parameters_finished:
4280         rem_anchor_token(')');
4281         expect(')', end_error);
4282
4283 end_error:
4284         restore_anchor_state(',', saved_comma_state);
4285 }
4286
4287 typedef enum construct_type_kind_t {
4288         CONSTRUCT_INVALID,
4289         CONSTRUCT_POINTER,
4290         CONSTRUCT_REFERENCE,
4291         CONSTRUCT_FUNCTION,
4292         CONSTRUCT_ARRAY
4293 } construct_type_kind_t;
4294
4295 typedef struct construct_type_t construct_type_t;
4296 struct construct_type_t {
4297         construct_type_kind_t  kind;
4298         construct_type_t      *next;
4299 };
4300
4301 typedef struct parsed_pointer_t parsed_pointer_t;
4302 struct parsed_pointer_t {
4303         construct_type_t  construct_type;
4304         type_qualifiers_t type_qualifiers;
4305         variable_t        *base_variable;  /**< MS __based extension. */
4306 };
4307
4308 typedef struct parsed_reference_t parsed_reference_t;
4309 struct parsed_reference_t {
4310         construct_type_t construct_type;
4311 };
4312
4313 typedef struct construct_function_type_t construct_function_type_t;
4314 struct construct_function_type_t {
4315         construct_type_t  construct_type;
4316         type_t           *function_type;
4317 };
4318
4319 typedef struct parsed_array_t parsed_array_t;
4320 struct parsed_array_t {
4321         construct_type_t  construct_type;
4322         type_qualifiers_t type_qualifiers;
4323         bool              is_static;
4324         bool              is_variable;
4325         expression_t     *size;
4326 };
4327
4328 typedef struct construct_base_type_t construct_base_type_t;
4329 struct construct_base_type_t {
4330         construct_type_t  construct_type;
4331         type_t           *type;
4332 };
4333
4334 static construct_type_t *parse_pointer_declarator(variable_t *base_variable)
4335 {
4336         eat('*');
4337
4338         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
4339         memset(pointer, 0, sizeof(pointer[0]));
4340         pointer->construct_type.kind = CONSTRUCT_POINTER;
4341         pointer->type_qualifiers     = parse_type_qualifiers();
4342         pointer->base_variable       = base_variable;
4343
4344         return &pointer->construct_type;
4345 }
4346
4347 static construct_type_t *parse_reference_declarator(void)
4348 {
4349         eat('&');
4350
4351         parsed_reference_t *reference = obstack_alloc(&temp_obst, sizeof(reference[0]));
4352         memset(reference, 0, sizeof(reference[0]));
4353         reference->construct_type.kind = CONSTRUCT_REFERENCE;
4354
4355         return (construct_type_t*)reference;
4356 }
4357
4358 static construct_type_t *parse_array_declarator(void)
4359 {
4360         eat('[');
4361         add_anchor_token(']');
4362
4363         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
4364         memset(array, 0, sizeof(array[0]));
4365         array->construct_type.kind = CONSTRUCT_ARRAY;
4366
4367         if (token.type == T_static) {
4368                 array->is_static = true;
4369                 next_token();
4370         }
4371
4372         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
4373         if (type_qualifiers != 0) {
4374                 if (token.type == T_static) {
4375                         array->is_static = true;
4376                         next_token();
4377                 }
4378         }
4379         array->type_qualifiers = type_qualifiers;
4380
4381         if (token.type == '*' && look_ahead(1)->type == ']') {
4382                 array->is_variable = true;
4383                 next_token();
4384         } else if (token.type != ']') {
4385                 expression_t *const size = parse_assignment_expression();
4386                 array->size = size;
4387                 mark_vars_read(size, NULL);
4388         }
4389
4390         rem_anchor_token(']');
4391         expect(']', end_error);
4392
4393 end_error:
4394         return &array->construct_type;
4395 }
4396
4397 static construct_type_t *parse_function_declarator(scope_t *scope,
4398                                                    decl_modifiers_t modifiers)
4399 {
4400         type_t          *type  = allocate_type_zero(TYPE_FUNCTION);
4401         function_type_t *ftype = &type->function;
4402
4403         ftype->linkage = current_linkage;
4404
4405         switch (modifiers & (DM_CDECL | DM_STDCALL | DM_FASTCALL | DM_THISCALL)) {
4406                 case DM_NONE:     break;
4407                 case DM_CDECL:    ftype->calling_convention = CC_CDECL;    break;
4408                 case DM_STDCALL:  ftype->calling_convention = CC_STDCALL;  break;
4409                 case DM_FASTCALL: ftype->calling_convention = CC_FASTCALL; break;
4410                 case DM_THISCALL: ftype->calling_convention = CC_THISCALL; break;
4411
4412                 default:
4413                         errorf(HERE, "multiple calling conventions in declaration");
4414                         break;
4415         }
4416
4417         parse_parameters(ftype, scope);
4418
4419         construct_function_type_t *construct_function_type =
4420                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
4421         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
4422         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
4423         construct_function_type->function_type       = type;
4424
4425         return &construct_function_type->construct_type;
4426 }
4427
4428 typedef struct parse_declarator_env_t {
4429         decl_modifiers_t   modifiers;
4430         symbol_t          *symbol;
4431         source_position_t  source_position;
4432         scope_t            parameters;
4433 } parse_declarator_env_t;
4434
4435 static construct_type_t *parse_inner_declarator(parse_declarator_env_t *env,
4436                 bool may_be_abstract)
4437 {
4438         /* construct a single linked list of construct_type_t's which describe
4439          * how to construct the final declarator type */
4440         construct_type_t *first      = NULL;
4441         construct_type_t *last       = NULL;
4442         gnu_attribute_t  *attributes = NULL;
4443
4444         decl_modifiers_t modifiers = parse_attributes(&attributes);
4445
4446         /* MS __based extension */
4447         based_spec_t base_spec;
4448         base_spec.base_variable = NULL;
4449
4450         for (;;) {
4451                 construct_type_t *type;
4452                 switch (token.type) {
4453                         case '&':
4454                                 if (!(c_mode & _CXX))
4455                                         errorf(HERE, "references are only available for C++");
4456                                 if (base_spec.base_variable != NULL && warning.other) {
4457                                         warningf(&base_spec.source_position,
4458                                                  "__based does not precede a pointer operator, ignored");
4459                                 }
4460                                 type = parse_reference_declarator();
4461                                 /* consumed */
4462                                 base_spec.base_variable = NULL;
4463                                 break;
4464
4465                         case '*':
4466                                 type = parse_pointer_declarator(base_spec.base_variable);
4467                                 /* consumed */
4468                                 base_spec.base_variable = NULL;
4469                                 break;
4470
4471                         case T__based:
4472                                 next_token();
4473                                 expect('(', end_error);
4474                                 add_anchor_token(')');
4475                                 parse_microsoft_based(&base_spec);
4476                                 rem_anchor_token(')');
4477                                 expect(')', end_error);
4478                                 continue;
4479
4480                         default:
4481                                 goto ptr_operator_end;
4482                 }
4483
4484                 if (last == NULL) {
4485                         first = type;
4486                         last  = type;
4487                 } else {
4488                         last->next = type;
4489                         last       = type;
4490                 }
4491
4492                 /* TODO: find out if this is correct */
4493                 modifiers |= parse_attributes(&attributes);
4494         }
4495 ptr_operator_end:
4496         if (base_spec.base_variable != NULL && warning.other) {
4497                 warningf(&base_spec.source_position,
4498                          "__based does not precede a pointer operator, ignored");
4499         }
4500
4501         if (env != NULL) {
4502                 modifiers      |= env->modifiers;
4503                 env->modifiers  = modifiers;
4504         }
4505
4506         construct_type_t *inner_types = NULL;
4507
4508         switch (token.type) {
4509         case T_IDENTIFIER:
4510                 if (env == NULL) {
4511                         errorf(HERE, "no identifier expected in typename");
4512                 } else {
4513                         env->symbol          = token.v.symbol;
4514                         env->source_position = token.source_position;
4515                 }
4516                 next_token();
4517                 break;
4518         case '(':
4519                 /* §6.7.6:2 footnote 126:  Empty parentheses in a type name are
4520                  * interpreted as ``function with no parameter specification'', rather
4521                  * than redundant parentheses around the omitted identifier. */
4522                 if (look_ahead(1)->type != ')') {
4523                         next_token();
4524                         add_anchor_token(')');
4525                         inner_types = parse_inner_declarator(env, may_be_abstract);
4526                         if (inner_types != NULL) {
4527                                 /* All later declarators only modify the return type */
4528                                 env = NULL;
4529                         }
4530                         rem_anchor_token(')');
4531                         expect(')', end_error);
4532                 }
4533                 break;
4534         default:
4535                 if (may_be_abstract)
4536                         break;
4537                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
4538                 eat_until_anchor();
4539                 return NULL;
4540         }
4541
4542         construct_type_t *p = last;
4543
4544         while (true) {
4545                 construct_type_t *type;
4546                 switch (token.type) {
4547                 case '(': {
4548                         scope_t *scope = NULL;
4549                         if (env != NULL)
4550                                 scope = &env->parameters;
4551
4552                         type = parse_function_declarator(scope, modifiers);
4553                         break;
4554                 }
4555                 case '[':
4556                         type = parse_array_declarator();
4557                         break;
4558                 default:
4559                         goto declarator_finished;
4560                 }
4561
4562                 /* insert in the middle of the list (behind p) */
4563                 if (p != NULL) {
4564                         type->next = p->next;
4565                         p->next    = type;
4566                 } else {
4567                         type->next = first;
4568                         first      = type;
4569                 }
4570                 if (last == p) {
4571                         last = type;
4572                 }
4573         }
4574
4575 declarator_finished:
4576         /* append inner_types at the end of the list, we don't to set last anymore
4577          * as it's not needed anymore */
4578         if (last == NULL) {
4579                 assert(first == NULL);
4580                 first = inner_types;
4581         } else {
4582                 last->next = inner_types;
4583         }
4584
4585         return first;
4586 end_error:
4587         return NULL;
4588 }
4589
4590 static void parse_declaration_attributes(entity_t *entity)
4591 {
4592         gnu_attribute_t  *attributes = NULL;
4593         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
4594
4595         if (entity == NULL)
4596                 return;
4597
4598         type_t *type;
4599         if (entity->kind == ENTITY_TYPEDEF) {
4600                 modifiers |= entity->typedefe.modifiers;
4601                 type       = entity->typedefe.type;
4602         } else {
4603                 assert(is_declaration(entity));
4604                 modifiers |= entity->declaration.modifiers;
4605                 type       = entity->declaration.type;
4606         }
4607         if (type == NULL)
4608                 return;
4609
4610         /* handle these strange/stupid mode attributes */
4611         gnu_attribute_t *attribute = attributes;
4612         for ( ; attribute != NULL; attribute = attribute->next) {
4613                 if (attribute->invalid)
4614                         continue;
4615
4616                 if (attribute->kind == GNU_AK_MODE) {
4617                         type = handle_mode_attribute(attribute, type);
4618                 } else if (attribute->kind == GNU_AK_ALIGNED) {
4619                         int alignment = 32; /* TODO: fill in maximum usefull alignment for target machine */
4620                         if (attribute->has_arguments)
4621                                 alignment = attribute->u.argument;
4622
4623                         if (entity->kind == ENTITY_TYPEDEF) {
4624                                 type_t *copy         = duplicate_type(type);
4625                                 copy->base.alignment = attribute->u.argument;
4626                                 type                 = identify_new_type(copy);
4627                         } else if(entity->kind == ENTITY_VARIABLE) {
4628                                 entity->variable.alignment = alignment;
4629                         } else if(entity->kind == ENTITY_COMPOUND_MEMBER) {
4630                                 entity->compound_member.alignment = alignment;
4631                         }
4632                 }
4633         }
4634
4635         type_modifiers_t type_modifiers = type->base.modifiers;
4636         if (modifiers & DM_TRANSPARENT_UNION)
4637                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
4638
4639         if (type->base.modifiers != type_modifiers) {
4640                 type_t *copy         = duplicate_type(type);
4641                 copy->base.modifiers = type_modifiers;
4642                 type                 = identify_new_type(copy);
4643         }
4644
4645         if (entity->kind == ENTITY_TYPEDEF) {
4646                 entity->typedefe.type      = type;
4647                 entity->typedefe.modifiers = modifiers;
4648         } else {
4649                 entity->declaration.type      = type;
4650                 entity->declaration.modifiers = modifiers;
4651         }
4652 }
4653
4654 static type_t *construct_declarator_type(construct_type_t *construct_list, type_t *type)
4655 {
4656         construct_type_t *iter = construct_list;
4657         for (; iter != NULL; iter = iter->next) {
4658                 switch (iter->kind) {
4659                 case CONSTRUCT_INVALID:
4660                         internal_errorf(HERE, "invalid type construction found");
4661                 case CONSTRUCT_FUNCTION: {
4662                         construct_function_type_t *construct_function_type
4663                                 = (construct_function_type_t*) iter;
4664
4665                         type_t *function_type = construct_function_type->function_type;
4666
4667                         function_type->function.return_type = type;
4668
4669                         type_t *skipped_return_type = skip_typeref(type);
4670                         /* §6.7.5.3:1 */
4671                         if (is_type_function(skipped_return_type)) {
4672                                 errorf(HERE, "function returning function is not allowed");
4673                         } else if (is_type_array(skipped_return_type)) {
4674                                 errorf(HERE, "function returning array is not allowed");
4675                         } else {
4676                                 if (skipped_return_type->base.qualifiers != 0 && warning.other) {
4677                                         warningf(HERE,
4678                                                 "type qualifiers in return type of function type are meaningless");
4679                                 }
4680                         }
4681
4682                         type = function_type;
4683                         break;
4684                 }
4685
4686                 case CONSTRUCT_POINTER: {
4687                         if (is_type_reference(skip_typeref(type)))
4688                                 errorf(HERE, "cannot declare a pointer to reference");
4689
4690                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
4691                         type = make_based_pointer_type(type, parsed_pointer->type_qualifiers, parsed_pointer->base_variable);
4692                         continue;
4693                 }
4694
4695                 case CONSTRUCT_REFERENCE:
4696                         if (is_type_reference(skip_typeref(type)))
4697                                 errorf(HERE, "cannot declare a reference to reference");
4698
4699                         type = make_reference_type(type);
4700                         continue;
4701
4702                 case CONSTRUCT_ARRAY: {
4703                         if (is_type_reference(skip_typeref(type)))
4704                                 errorf(HERE, "cannot declare an array of references");
4705
4706                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
4707                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY);
4708
4709                         expression_t *size_expression = parsed_array->size;
4710                         if (size_expression != NULL) {
4711                                 size_expression
4712                                         = create_implicit_cast(size_expression, type_size_t);
4713                         }
4714
4715                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
4716                         array_type->array.element_type    = type;
4717                         array_type->array.is_static       = parsed_array->is_static;
4718                         array_type->array.is_variable     = parsed_array->is_variable;
4719                         array_type->array.size_expression = size_expression;
4720
4721                         if (size_expression != NULL) {
4722                                 if (is_constant_expression(size_expression)) {
4723                                         array_type->array.size_constant = true;
4724                                         array_type->array.size
4725                                                 = fold_constant(size_expression);
4726                                 } else {
4727                                         array_type->array.is_vla = true;
4728                                 }
4729                         }
4730
4731                         type_t *skipped_type = skip_typeref(type);
4732                         /* §6.7.5.2:1 */
4733                         if (is_type_incomplete(skipped_type)) {
4734                                 errorf(HERE, "array of incomplete type '%T' is not allowed", type);
4735                         } else if (is_type_function(skipped_type)) {
4736                                 errorf(HERE, "array of functions is not allowed");
4737                         }
4738                         type = array_type;
4739                         break;
4740                 }
4741                 }
4742
4743                 /* The function type was constructed earlier.  Freeing it here will
4744                  * destroy other types. */
4745                 if (iter->kind == CONSTRUCT_FUNCTION) {
4746                         type = typehash_insert(type);
4747                 } else {
4748                         type = identify_new_type(type);
4749                 }
4750         }
4751
4752         return type;
4753 }
4754
4755 static type_t *automatic_type_conversion(type_t *orig_type);
4756
4757 static type_t *semantic_parameter(const source_position_t *pos,
4758                                   type_t *type,
4759                                   const declaration_specifiers_t *specifiers,
4760                                   symbol_t *symbol)
4761 {
4762         /* §6.7.5.3:7  A declaration of a parameter as ``array of type''
4763          *             shall be adjusted to ``qualified pointer to type'',
4764          *             [...]
4765          * §6.7.5.3:8  A declaration of a parameter as ``function returning
4766          *             type'' shall be adjusted to ``pointer to function
4767          *             returning type'', as in 6.3.2.1. */
4768         type = automatic_type_conversion(type);
4769
4770         if (specifiers->is_inline && is_type_valid(type)) {
4771                 errorf(pos, "parameter '%Y' declared 'inline'", symbol);
4772         }
4773
4774         /* §6.9.1:6  The declarations in the declaration list shall contain
4775          *           no storage-class specifier other than register and no
4776          *           initializations. */
4777         if (specifiers->thread_local || (
4778                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4779                         specifiers->storage_class != STORAGE_CLASS_REGISTER)
4780            ) {
4781                 errorf(pos, "invalid storage class for parameter '%Y'", symbol);
4782         }
4783
4784         /* delay test for incomplete type, because we might have (void)
4785          * which is legal but incomplete... */
4786
4787         return type;
4788 }
4789
4790 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
4791                                   declarator_flags_t flags)
4792 {
4793         parse_declarator_env_t env;
4794         memset(&env, 0, sizeof(env));
4795         env.modifiers = specifiers->modifiers;
4796
4797         construct_type_t *construct_type =
4798                 parse_inner_declarator(&env, (flags & DECL_MAY_BE_ABSTRACT) != 0);
4799         type_t           *orig_type      =
4800                 construct_declarator_type(construct_type, specifiers->type);
4801         type_t           *type           = skip_typeref(orig_type);
4802
4803         if (construct_type != NULL) {
4804                 obstack_free(&temp_obst, construct_type);
4805         }
4806
4807         entity_t *entity;
4808         if (specifiers->storage_class == STORAGE_CLASS_TYPEDEF) {
4809                 entity                       = allocate_entity_zero(ENTITY_TYPEDEF);
4810                 entity->base.symbol          = env.symbol;
4811                 entity->base.source_position = env.source_position;
4812                 entity->typedefe.type        = orig_type;
4813
4814                 if (anonymous_entity != NULL) {
4815                         if (is_type_compound(type)) {
4816                                 assert(anonymous_entity->compound.alias == NULL);
4817                                 assert(anonymous_entity->kind == ENTITY_STRUCT ||
4818                                        anonymous_entity->kind == ENTITY_UNION);
4819                                 anonymous_entity->compound.alias = entity;
4820                                 anonymous_entity = NULL;
4821                         } else if (is_type_enum(type)) {
4822                                 assert(anonymous_entity->enume.alias == NULL);
4823                                 assert(anonymous_entity->kind == ENTITY_ENUM);
4824                                 anonymous_entity->enume.alias = entity;
4825                                 anonymous_entity = NULL;
4826                         }
4827                 }
4828         } else {
4829                 /* create a declaration type entity */
4830                 if (flags & DECL_CREATE_COMPOUND_MEMBER) {
4831                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
4832
4833                         if (env.symbol != NULL) {
4834                                 if (specifiers->is_inline && is_type_valid(type)) {
4835                                         errorf(&env.source_position,
4836                                                         "compound member '%Y' declared 'inline'", env.symbol);
4837                                 }
4838
4839                                 if (specifiers->thread_local ||
4840                                                 specifiers->storage_class != STORAGE_CLASS_NONE) {
4841                                         errorf(&env.source_position,
4842                                                         "compound member '%Y' must have no storage class",
4843                                                         env.symbol);
4844                                 }
4845                         }
4846                 } else if (flags & DECL_IS_PARAMETER) {
4847                         orig_type = semantic_parameter(&env.source_position, orig_type,
4848                                                        specifiers, env.symbol);
4849
4850                         entity = allocate_entity_zero(ENTITY_PARAMETER);
4851                 } else if (is_type_function(type)) {
4852                         entity = allocate_entity_zero(ENTITY_FUNCTION);
4853
4854                         entity->function.is_inline  = specifiers->is_inline;
4855                         entity->function.parameters = env.parameters;
4856
4857                         if (env.symbol != NULL) {
4858                                 if (specifiers->thread_local || (
4859                                                         specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4860                                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4861                                                         specifiers->storage_class != STORAGE_CLASS_STATIC
4862                                                 )) {
4863                                         errorf(&env.source_position,
4864                                                         "invalid storage class for function '%Y'", env.symbol);
4865                                 }
4866                         }
4867                 } else {
4868                         entity = allocate_entity_zero(ENTITY_VARIABLE);
4869
4870                         entity->variable.get_property_sym = specifiers->get_property_sym;
4871                         entity->variable.put_property_sym = specifiers->put_property_sym;
4872
4873                         entity->variable.thread_local = specifiers->thread_local;
4874
4875                         if (env.symbol != NULL) {
4876                                 if (specifiers->is_inline && is_type_valid(type)) {
4877                                         errorf(&env.source_position,
4878                                                         "variable '%Y' declared 'inline'", env.symbol);
4879                                 }
4880
4881                                 bool invalid_storage_class = false;
4882                                 if (current_scope == file_scope) {
4883                                         if (specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4884                                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4885                                                         specifiers->storage_class != STORAGE_CLASS_STATIC) {
4886                                                 invalid_storage_class = true;
4887                                         }
4888                                 } else {
4889                                         if (specifiers->thread_local &&
4890                                                         specifiers->storage_class == STORAGE_CLASS_NONE) {
4891                                                 invalid_storage_class = true;
4892                                         }
4893                                 }
4894                                 if (invalid_storage_class) {
4895                                         errorf(&env.source_position,
4896                                                         "invalid storage class for variable '%Y'", env.symbol);
4897                                 }
4898                         }
4899                 }
4900
4901                 if (env.symbol != NULL) {
4902                         entity->base.symbol          = env.symbol;
4903                         entity->base.source_position = env.source_position;
4904                 } else {
4905                         entity->base.source_position = specifiers->source_position;
4906                 }
4907                 entity->base.namespc                  = NAMESPACE_NORMAL;
4908                 entity->declaration.type              = orig_type;
4909                 entity->declaration.modifiers         = env.modifiers;
4910                 entity->declaration.deprecated_string = specifiers->deprecated_string;
4911
4912                 storage_class_t storage_class = specifiers->storage_class;
4913                 entity->declaration.declared_storage_class = storage_class;
4914
4915                 if (storage_class == STORAGE_CLASS_NONE && current_scope != file_scope)
4916                         storage_class = STORAGE_CLASS_AUTO;
4917                 entity->declaration.storage_class = storage_class;
4918         }
4919
4920         parse_declaration_attributes(entity);
4921
4922         return entity;
4923 }
4924
4925 static type_t *parse_abstract_declarator(type_t *base_type)
4926 {
4927         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4928
4929         type_t *result = construct_declarator_type(construct_type, base_type);
4930         if (construct_type != NULL) {
4931                 obstack_free(&temp_obst, construct_type);
4932         }
4933
4934         return result;
4935 }
4936
4937 /**
4938  * Check if the declaration of main is suspicious.  main should be a
4939  * function with external linkage, returning int, taking either zero
4940  * arguments, two, or three arguments of appropriate types, ie.
4941  *
4942  * int main([ int argc, char **argv [, char **env ] ]).
4943  *
4944  * @param decl    the declaration to check
4945  * @param type    the function type of the declaration
4946  */
4947 static void check_type_of_main(const entity_t *entity)
4948 {
4949         const source_position_t *pos = &entity->base.source_position;
4950         if (entity->kind != ENTITY_FUNCTION) {
4951                 warningf(pos, "'main' is not a function");
4952                 return;
4953         }
4954
4955         if (entity->declaration.storage_class == STORAGE_CLASS_STATIC) {
4956                 warningf(pos, "'main' is normally a non-static function");
4957         }
4958
4959         type_t *type = skip_typeref(entity->declaration.type);
4960         assert(is_type_function(type));
4961
4962         function_type_t *func_type = &type->function;
4963         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4964                 warningf(pos, "return type of 'main' should be 'int', but is '%T'",
4965                          func_type->return_type);
4966         }
4967         const function_parameter_t *parm = func_type->parameters;
4968         if (parm != NULL) {
4969                 type_t *const first_type = parm->type;
4970                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4971                         warningf(pos,
4972                                  "first argument of 'main' should be 'int', but is '%T'",
4973                                  first_type);
4974                 }
4975                 parm = parm->next;
4976                 if (parm != NULL) {
4977                         type_t *const second_type = parm->type;
4978                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4979                                 warningf(pos, "second argument of 'main' should be 'char**', but is '%T'", second_type);
4980                         }
4981                         parm = parm->next;
4982                         if (parm != NULL) {
4983                                 type_t *const third_type = parm->type;
4984                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4985                                         warningf(pos, "third argument of 'main' should be 'char**', but is '%T'", third_type);
4986                                 }
4987                                 parm = parm->next;
4988                                 if (parm != NULL)
4989                                         goto warn_arg_count;
4990                         }
4991                 } else {
4992 warn_arg_count:
4993                         warningf(pos, "'main' takes only zero, two or three arguments");
4994                 }
4995         }
4996 }
4997
4998 /**
4999  * Check if a symbol is the equal to "main".
5000  */
5001 static bool is_sym_main(const symbol_t *const sym)
5002 {
5003         return strcmp(sym->string, "main") == 0;
5004 }
5005
5006 static void error_redefined_as_different_kind(const source_position_t *pos,
5007                 const entity_t *old, entity_kind_t new_kind)
5008 {
5009         errorf(pos, "redeclaration of %s '%Y' as %s (declared %P)",
5010                get_entity_kind_name(old->kind), old->base.symbol,
5011                get_entity_kind_name(new_kind), &old->base.source_position);
5012 }
5013
5014 /**
5015  * record entities for the NAMESPACE_NORMAL, and produce error messages/warnings
5016  * for various problems that occur for multiple definitions
5017  */
5018 static entity_t *record_entity(entity_t *entity, const bool is_definition)
5019 {
5020         const symbol_t *const    symbol  = entity->base.symbol;
5021         const namespace_tag_t    namespc = (namespace_tag_t)entity->base.namespc;
5022         const source_position_t *pos     = &entity->base.source_position;
5023
5024         /* can happen in error cases */
5025         if (symbol == NULL)
5026                 return entity;
5027
5028         entity_t *previous_entity = get_entity(symbol, namespc);
5029         /* pushing the same entity twice will break the stack structure */
5030         assert(previous_entity != entity);
5031
5032         if (entity->kind == ENTITY_FUNCTION) {
5033                 type_t *const orig_type = entity->declaration.type;
5034                 type_t *const type      = skip_typeref(orig_type);
5035
5036                 assert(is_type_function(type));
5037                 if (type->function.unspecified_parameters &&
5038                                 warning.strict_prototypes &&
5039                                 previous_entity == NULL) {
5040                         warningf(pos, "function declaration '%#T' is not a prototype",
5041                                          orig_type, symbol);
5042                 }
5043
5044                 if (warning.main && current_scope == file_scope
5045                                 && is_sym_main(symbol)) {
5046                         check_type_of_main(entity);
5047                 }
5048         }
5049
5050         if (is_declaration(entity) &&
5051                         warning.nested_externs &&
5052                         entity->declaration.storage_class == STORAGE_CLASS_EXTERN &&
5053                         current_scope != file_scope) {
5054                 warningf(pos, "nested extern declaration of '%#T'",
5055                          entity->declaration.type, symbol);
5056         }
5057
5058         if (previous_entity != NULL &&
5059                         previous_entity->base.parent_scope == &current_function->parameters &&
5060                         previous_entity->base.parent_scope->depth + 1 == current_scope->depth) {
5061                 assert(previous_entity->kind == ENTITY_PARAMETER);
5062                 errorf(pos,
5063                        "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
5064                                          entity->declaration.type, symbol,
5065                                          previous_entity->declaration.type, symbol,
5066                                          &previous_entity->base.source_position);
5067                 goto finish;
5068         }
5069
5070         if (previous_entity != NULL &&
5071                         previous_entity->base.parent_scope == current_scope) {
5072                 if (previous_entity->kind != entity->kind) {
5073                         error_redefined_as_different_kind(pos, previous_entity,
5074                                                           entity->kind);
5075                         goto finish;
5076                 }
5077                 if (previous_entity->kind == ENTITY_ENUM_VALUE) {
5078                         errorf(pos, "redeclaration of enum entry '%Y' (declared %P)",
5079                                    symbol, &previous_entity->base.source_position);
5080                         goto finish;
5081                 }
5082                 if (previous_entity->kind == ENTITY_TYPEDEF) {
5083                         /* TODO: C++ allows this for exactly the same type */
5084                         errorf(pos, "redefinition of typedef '%Y' (declared %P)",
5085                                symbol, &previous_entity->base.source_position);
5086                         goto finish;
5087                 }
5088
5089                 /* at this point we should have only VARIABLES or FUNCTIONS */
5090                 assert(is_declaration(previous_entity) && is_declaration(entity));
5091
5092                 declaration_t *const prev_decl = &previous_entity->declaration;
5093                 declaration_t *const decl      = &entity->declaration;
5094
5095                 /* can happen for K&R style declarations */
5096                 if (prev_decl->type       == NULL             &&
5097                                 previous_entity->kind == ENTITY_PARAMETER &&
5098                                 entity->kind          == ENTITY_PARAMETER) {
5099                         prev_decl->type                   = decl->type;
5100                         prev_decl->storage_class          = decl->storage_class;
5101                         prev_decl->declared_storage_class = decl->declared_storage_class;
5102                         prev_decl->modifiers              = decl->modifiers;
5103                         prev_decl->deprecated_string      = decl->deprecated_string;
5104                         return previous_entity;
5105                 }
5106
5107                 type_t *const orig_type = decl->type;
5108                 assert(orig_type != NULL);
5109                 type_t *const type      = skip_typeref(orig_type);
5110                 type_t *      prev_type = skip_typeref(prev_decl->type);
5111
5112                 if (!types_compatible(type, prev_type)) {
5113                         errorf(pos,
5114                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
5115                                    orig_type, symbol, prev_decl->type, symbol,
5116                                    &previous_entity->base.source_position);
5117                 } else {
5118                         unsigned old_storage_class = prev_decl->storage_class;
5119                         if (warning.redundant_decls               &&
5120                                         is_definition                     &&
5121                                         !prev_decl->used                  &&
5122                                         !(prev_decl->modifiers & DM_USED) &&
5123                                         prev_decl->storage_class == STORAGE_CLASS_STATIC) {
5124                                 warningf(&previous_entity->base.source_position,
5125                                          "unnecessary static forward declaration for '%#T'",
5126                                          prev_decl->type, symbol);
5127                         }
5128
5129                         unsigned new_storage_class = decl->storage_class;
5130                         if (is_type_incomplete(prev_type)) {
5131                                 prev_decl->type = type;
5132                                 prev_type       = type;
5133                         }
5134
5135                         /* pretend no storage class means extern for function
5136                          * declarations (except if the previous declaration is neither
5137                          * none nor extern) */
5138                         if (entity->kind == ENTITY_FUNCTION) {
5139                                 if (prev_type->function.unspecified_parameters) {
5140                                         prev_decl->type = type;
5141                                         prev_type       = type;
5142                                 }
5143
5144                                 switch (old_storage_class) {
5145                                 case STORAGE_CLASS_NONE:
5146                                         old_storage_class = STORAGE_CLASS_EXTERN;
5147                                         /* FALLTHROUGH */
5148
5149                                 case STORAGE_CLASS_EXTERN:
5150                                         if (is_definition) {
5151                                                 if (warning.missing_prototypes &&
5152                                                     prev_type->function.unspecified_parameters &&
5153                                                     !is_sym_main(symbol)) {
5154                                                         warningf(pos, "no previous prototype for '%#T'",
5155                                                                          orig_type, symbol);
5156                                                 }
5157                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
5158                                                 new_storage_class = STORAGE_CLASS_EXTERN;
5159                                         }
5160                                         break;
5161
5162                                 default:
5163                                         break;
5164                                 }
5165                         }
5166
5167                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
5168                                         new_storage_class == STORAGE_CLASS_EXTERN) {
5169 warn_redundant_declaration:
5170                                 if (!is_definition           &&
5171                                     warning.redundant_decls  &&
5172                                     is_type_valid(prev_type) &&
5173                                     strcmp(previous_entity->base.source_position.input_name,
5174                                            "<builtin>") != 0) {
5175                                         warningf(pos,
5176                                                  "redundant declaration for '%Y' (declared %P)",
5177                                                  symbol, &previous_entity->base.source_position);
5178                                 }
5179                         } else if (current_function == NULL) {
5180                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
5181                                     new_storage_class == STORAGE_CLASS_STATIC) {
5182                                         errorf(pos,
5183                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
5184                                                symbol, &previous_entity->base.source_position);
5185                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
5186                                         prev_decl->storage_class          = STORAGE_CLASS_NONE;
5187                                         prev_decl->declared_storage_class = STORAGE_CLASS_NONE;
5188                                 } else {
5189                                         /* ISO/IEC 14882:1998(E) §C.1.2:1 */
5190                                         if (c_mode & _CXX)
5191                                                 goto error_redeclaration;
5192                                         goto warn_redundant_declaration;
5193                                 }
5194                         } else if (is_type_valid(prev_type)) {
5195                                 if (old_storage_class == new_storage_class) {
5196 error_redeclaration:
5197                                         errorf(pos, "redeclaration of '%Y' (declared %P)",
5198                                                symbol, &previous_entity->base.source_position);
5199                                 } else {
5200                                         errorf(pos,
5201                                                "redeclaration of '%Y' with different linkage (declared %P)",
5202                                                symbol, &previous_entity->base.source_position);
5203                                 }
5204                         }
5205                 }
5206
5207                 prev_decl->modifiers |= decl->modifiers;
5208                 if (entity->kind == ENTITY_FUNCTION) {
5209                         previous_entity->function.is_inline |= entity->function.is_inline;
5210                 }
5211                 return previous_entity;
5212         }
5213
5214         if (entity->kind == ENTITY_FUNCTION) {
5215                 if (is_definition &&
5216                                 entity->declaration.storage_class != STORAGE_CLASS_STATIC) {
5217                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
5218                                 warningf(pos, "no previous prototype for '%#T'",
5219                                          entity->declaration.type, symbol);
5220                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
5221                                 warningf(pos, "no previous declaration for '%#T'",
5222                                          entity->declaration.type, symbol);
5223                         }
5224                 }
5225         } else if (warning.missing_declarations &&
5226                         entity->kind == ENTITY_VARIABLE &&
5227                         current_scope == file_scope) {
5228                 declaration_t *declaration = &entity->declaration;
5229                 if (declaration->storage_class == STORAGE_CLASS_NONE) {
5230                         warningf(pos, "no previous declaration for '%#T'",
5231                                  declaration->type, symbol);
5232                 }
5233         }
5234
5235 finish:
5236         assert(entity->base.parent_scope == NULL);
5237         assert(current_scope != NULL);
5238
5239         entity->base.parent_scope = current_scope;
5240         entity->base.namespc      = NAMESPACE_NORMAL;
5241         environment_push(entity);
5242         append_entity(current_scope, entity);
5243
5244         return entity;
5245 }
5246
5247 static void parser_error_multiple_definition(entity_t *entity,
5248                 const source_position_t *source_position)
5249 {
5250         errorf(source_position, "multiple definition of '%Y' (declared %P)",
5251                entity->base.symbol, &entity->base.source_position);
5252 }
5253
5254 static bool is_declaration_specifier(const token_t *token,
5255                                      bool only_specifiers_qualifiers)
5256 {
5257         switch (token->type) {
5258                 TYPE_SPECIFIERS
5259                 TYPE_QUALIFIERS
5260                         return true;
5261                 case T_IDENTIFIER:
5262                         return is_typedef_symbol(token->v.symbol);
5263
5264                 case T___extension__:
5265                 STORAGE_CLASSES
5266                         return !only_specifiers_qualifiers;
5267
5268                 default:
5269                         return false;
5270         }
5271 }
5272
5273 static void parse_init_declarator_rest(entity_t *entity)
5274 {
5275         assert(is_declaration(entity));
5276         declaration_t *const declaration = &entity->declaration;
5277
5278         eat('=');
5279
5280         type_t *orig_type = declaration->type;
5281         type_t *type      = skip_typeref(orig_type);
5282
5283         if (entity->kind == ENTITY_VARIABLE
5284                         && entity->variable.initializer != NULL) {
5285                 parser_error_multiple_definition(entity, HERE);
5286         }
5287
5288         bool must_be_constant = false;
5289         if (declaration->storage_class == STORAGE_CLASS_STATIC ||
5290             entity->base.parent_scope  == file_scope) {
5291                 must_be_constant = true;
5292         }
5293
5294         if (is_type_function(type)) {
5295                 errorf(&entity->base.source_position,
5296                        "function '%#T' is initialized like a variable",
5297                        orig_type, entity->base.symbol);
5298                 orig_type = type_error_type;
5299         }
5300
5301         parse_initializer_env_t env;
5302         env.type             = orig_type;
5303         env.must_be_constant = must_be_constant;
5304         env.entity           = entity;
5305         current_init_decl    = entity;
5306
5307         initializer_t *initializer = parse_initializer(&env);
5308         current_init_decl = NULL;
5309
5310         if (entity->kind == ENTITY_VARIABLE) {
5311                 /* § 6.7.5:22  array initializers for arrays with unknown size
5312                  * determine the array type size */
5313                 declaration->type            = env.type;
5314                 entity->variable.initializer = initializer;
5315         }
5316 }
5317
5318 /* parse rest of a declaration without any declarator */
5319 static void parse_anonymous_declaration_rest(
5320                 const declaration_specifiers_t *specifiers)
5321 {
5322         eat(';');
5323         anonymous_entity = NULL;
5324
5325         if (warning.other) {
5326                 if (specifiers->storage_class != STORAGE_CLASS_NONE ||
5327                                 specifiers->thread_local) {
5328                         warningf(&specifiers->source_position,
5329                                  "useless storage class in empty declaration");
5330                 }
5331
5332                 type_t *type = specifiers->type;
5333                 switch (type->kind) {
5334                         case TYPE_COMPOUND_STRUCT:
5335                         case TYPE_COMPOUND_UNION: {
5336                                 if (type->compound.compound->base.symbol == NULL) {
5337                                         warningf(&specifiers->source_position,
5338                                                  "unnamed struct/union that defines no instances");
5339                                 }
5340                                 break;
5341                         }
5342
5343                         case TYPE_ENUM:
5344                                 break;
5345
5346                         default:
5347                                 warningf(&specifiers->source_position, "empty declaration");
5348                                 break;
5349                 }
5350         }
5351 }
5352
5353 static void check_variable_type_complete(entity_t *ent)
5354 {
5355         if (ent->kind != ENTITY_VARIABLE)
5356                 return;
5357
5358         /* §6.7:7  If an identifier for an object is declared with no linkage, the
5359          *         type for the object shall be complete [...] */
5360         declaration_t *decl = &ent->declaration;
5361         if (decl->storage_class != STORAGE_CLASS_NONE)
5362                 return;
5363
5364         type_t *const orig_type = decl->type;
5365         type_t *const type      = skip_typeref(orig_type);
5366         if (!is_type_incomplete(type))
5367                 return;
5368
5369         /* GCC allows global arrays without size and assigns them a length of one,
5370          * if no different declaration follows */
5371         if (is_type_array(type) &&
5372                         c_mode & _GNUC      &&
5373                         ent->base.parent_scope == file_scope) {
5374                 ARR_APP1(declaration_t*, incomplete_arrays, decl);
5375                 return;
5376         }
5377
5378         errorf(&ent->base.source_position, "variable '%#T' has incomplete type",
5379                         orig_type, ent->base.symbol);
5380 }
5381
5382
5383 static void parse_declaration_rest(entity_t *ndeclaration,
5384                 const declaration_specifiers_t *specifiers,
5385                 parsed_declaration_func         finished_declaration,
5386                 declarator_flags_t              flags)
5387 {
5388         add_anchor_token(';');
5389         add_anchor_token(',');
5390         while (true) {
5391                 entity_t *entity = finished_declaration(ndeclaration, token.type == '=');
5392
5393                 if (token.type == '=') {
5394                         parse_init_declarator_rest(entity);
5395                 } else if (entity->kind == ENTITY_VARIABLE) {
5396                         /* ISO/IEC 14882:1998(E) §8.5.3:3  The initializer can be omitted
5397                          * [...] where the extern specifier is explicitly used. */
5398                         declaration_t *decl = &entity->declaration;
5399                         if (decl->storage_class != STORAGE_CLASS_EXTERN) {
5400                                 type_t *type = decl->type;
5401                                 if (is_type_reference(skip_typeref(type))) {
5402                                         errorf(&entity->base.source_position,
5403                                                         "reference '%#T' must be initialized",
5404                                                         type, entity->base.symbol);
5405                                 }
5406                         }
5407                 }
5408
5409                 check_variable_type_complete(entity);
5410
5411                 if (token.type != ',')
5412                         break;
5413                 eat(',');
5414
5415                 add_anchor_token('=');
5416                 ndeclaration = parse_declarator(specifiers, flags);
5417                 rem_anchor_token('=');
5418         }
5419         expect(';', end_error);
5420
5421 end_error:
5422         anonymous_entity = NULL;
5423         rem_anchor_token(';');
5424         rem_anchor_token(',');
5425 }
5426
5427 static entity_t *finished_kr_declaration(entity_t *entity, bool is_definition)
5428 {
5429         symbol_t *symbol = entity->base.symbol;
5430         if (symbol == NULL) {
5431                 errorf(HERE, "anonymous declaration not valid as function parameter");
5432                 return entity;
5433         }
5434
5435         assert(entity->base.namespc == NAMESPACE_NORMAL);
5436         entity_t *previous_entity = get_entity(symbol, NAMESPACE_NORMAL);
5437         if (previous_entity == NULL
5438                         || previous_entity->base.parent_scope != current_scope) {
5439                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
5440                        symbol);
5441                 return entity;
5442         }
5443
5444         if (is_definition) {
5445                 errorf(HERE, "parameter '%Y' is initialised", entity->base.symbol);
5446         }
5447
5448         return record_entity(entity, false);
5449 }
5450
5451 static void parse_declaration(parsed_declaration_func finished_declaration,
5452                               declarator_flags_t      flags)
5453 {
5454         declaration_specifiers_t specifiers;
5455         memset(&specifiers, 0, sizeof(specifiers));
5456
5457         add_anchor_token(';');
5458         parse_declaration_specifiers(&specifiers);
5459         rem_anchor_token(';');
5460
5461         if (token.type == ';') {
5462                 parse_anonymous_declaration_rest(&specifiers);
5463         } else {
5464                 entity_t *entity = parse_declarator(&specifiers, flags);
5465                 parse_declaration_rest(entity, &specifiers, finished_declaration, flags);
5466         }
5467 }
5468
5469 static type_t *get_default_promoted_type(type_t *orig_type)
5470 {
5471         type_t *result = orig_type;
5472
5473         type_t *type = skip_typeref(orig_type);
5474         if (is_type_integer(type)) {
5475                 result = promote_integer(type);
5476         } else if (type == type_float) {
5477                 result = type_double;
5478         }
5479
5480         return result;
5481 }
5482
5483 static void parse_kr_declaration_list(entity_t *entity)
5484 {
5485         if (entity->kind != ENTITY_FUNCTION)
5486                 return;
5487
5488         type_t *type = skip_typeref(entity->declaration.type);
5489         assert(is_type_function(type));
5490         if (!type->function.kr_style_parameters)
5491                 return;
5492
5493
5494         add_anchor_token('{');
5495
5496         /* push function parameters */
5497         size_t const  top       = environment_top();
5498         scope_t      *old_scope = scope_push(&entity->function.parameters);
5499
5500         entity_t *parameter = entity->function.parameters.entities;
5501         for ( ; parameter != NULL; parameter = parameter->base.next) {
5502                 assert(parameter->base.parent_scope == NULL);
5503                 parameter->base.parent_scope = current_scope;
5504                 environment_push(parameter);
5505         }
5506
5507         /* parse declaration list */
5508         for (;;) {
5509                 switch (token.type) {
5510                         DECLARATION_START
5511                         case T___extension__:
5512                         /* This covers symbols, which are no type, too, and results in
5513                          * better error messages.  The typical cases are misspelled type
5514                          * names and missing includes. */
5515                         case T_IDENTIFIER:
5516                                 parse_declaration(finished_kr_declaration, DECL_IS_PARAMETER);
5517                                 break;
5518                         default:
5519                                 goto decl_list_end;
5520                 }
5521         }
5522 decl_list_end:
5523
5524         /* pop function parameters */
5525         assert(current_scope == &entity->function.parameters);
5526         scope_pop(old_scope);
5527         environment_pop_to(top);
5528
5529         /* update function type */
5530         type_t *new_type = duplicate_type(type);
5531
5532         function_parameter_t *parameters     = NULL;
5533         function_parameter_t *last_parameter = NULL;
5534
5535         parameter = entity->function.parameters.entities;
5536         for (; parameter != NULL; parameter = parameter->base.next) {
5537                 type_t *parameter_type = parameter->declaration.type;
5538                 if (parameter_type == NULL) {
5539                         if (strict_mode) {
5540                                 errorf(HERE, "no type specified for function parameter '%Y'",
5541                                        parameter->base.symbol);
5542                         } else {
5543                                 if (warning.implicit_int) {
5544                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
5545                                                  parameter->base.symbol);
5546                                 }
5547                                 parameter_type              = type_int;
5548                                 parameter->declaration.type = parameter_type;
5549                         }
5550                 }
5551
5552                 semantic_parameter_incomplete(parameter);
5553                 parameter_type = parameter->declaration.type;
5554
5555                 /*
5556                  * we need the default promoted types for the function type
5557                  */
5558                 parameter_type = get_default_promoted_type(parameter_type);
5559
5560                 function_parameter_t *function_parameter
5561                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
5562                 memset(function_parameter, 0, sizeof(function_parameter[0]));
5563
5564                 function_parameter->type = parameter_type;
5565                 if (last_parameter != NULL) {
5566                         last_parameter->next = function_parameter;
5567                 } else {
5568                         parameters = function_parameter;
5569                 }
5570                 last_parameter = function_parameter;
5571         }
5572
5573         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
5574          * prototype */
5575         new_type->function.parameters             = parameters;
5576         new_type->function.unspecified_parameters = true;
5577
5578         new_type = identify_new_type(new_type);
5579
5580         entity->declaration.type = new_type;
5581
5582         rem_anchor_token('{');
5583 }
5584
5585 static bool first_err = true;
5586
5587 /**
5588  * When called with first_err set, prints the name of the current function,
5589  * else does noting.
5590  */
5591 static void print_in_function(void)
5592 {
5593         if (first_err) {
5594                 first_err = false;
5595                 diagnosticf("%s: In function '%Y':\n",
5596                             current_function->base.base.source_position.input_name,
5597                             current_function->base.base.symbol);
5598         }
5599 }
5600
5601 /**
5602  * Check if all labels are defined in the current function.
5603  * Check if all labels are used in the current function.
5604  */
5605 static void check_labels(void)
5606 {
5607         for (const goto_statement_t *goto_statement = goto_first;
5608             goto_statement != NULL;
5609             goto_statement = goto_statement->next) {
5610                 /* skip computed gotos */
5611                 if (goto_statement->expression != NULL)
5612                         continue;
5613
5614                 label_t *label = goto_statement->label;
5615
5616                 label->used = true;
5617                 if (label->base.source_position.input_name == NULL) {
5618                         print_in_function();
5619                         errorf(&goto_statement->base.source_position,
5620                                "label '%Y' used but not defined", label->base.symbol);
5621                  }
5622         }
5623
5624         if (warning.unused_label) {
5625                 for (const label_statement_t *label_statement = label_first;
5626                          label_statement != NULL;
5627                          label_statement = label_statement->next) {
5628                         label_t *label = label_statement->label;
5629
5630                         if (! label->used) {
5631                                 print_in_function();
5632                                 warningf(&label_statement->base.source_position,
5633                                          "label '%Y' defined but not used", label->base.symbol);
5634                         }
5635                 }
5636         }
5637 }
5638
5639 static void warn_unused_entity(entity_t *entity, entity_t *last)
5640 {
5641         entity_t const *const end = last != NULL ? last->base.next : NULL;
5642         for (; entity != end; entity = entity->base.next) {
5643                 if (!is_declaration(entity))
5644                         continue;
5645
5646                 declaration_t *declaration = &entity->declaration;
5647                 if (declaration->implicit)
5648                         continue;
5649
5650                 if (!declaration->used) {
5651                         print_in_function();
5652                         const char *what = get_entity_kind_name(entity->kind);
5653                         warningf(&entity->base.source_position, "%s '%Y' is unused",
5654                                  what, entity->base.symbol);
5655                 } else if (entity->kind == ENTITY_VARIABLE && !entity->variable.read) {
5656                         print_in_function();
5657                         const char *what = get_entity_kind_name(entity->kind);
5658                         warningf(&entity->base.source_position, "%s '%Y' is never read",
5659                                  what, entity->base.symbol);
5660                 }
5661         }
5662 }
5663
5664 static void check_unused_variables(statement_t *const stmt, void *const env)
5665 {
5666         (void)env;
5667
5668         switch (stmt->kind) {
5669                 case STATEMENT_DECLARATION: {
5670                         declaration_statement_t const *const decls = &stmt->declaration;
5671                         warn_unused_entity(decls->declarations_begin,
5672                                            decls->declarations_end);
5673                         return;
5674                 }
5675
5676                 case STATEMENT_FOR:
5677                         warn_unused_entity(stmt->fors.scope.entities, NULL);
5678                         return;
5679
5680                 default:
5681                         return;
5682         }
5683 }
5684
5685 /**
5686  * Check declarations of current_function for unused entities.
5687  */
5688 static void check_declarations(void)
5689 {
5690         if (warning.unused_parameter) {
5691                 const scope_t *scope = &current_function->parameters;
5692
5693                 /* do not issue unused warnings for main */
5694                 if (!is_sym_main(current_function->base.base.symbol)) {
5695                         warn_unused_entity(scope->entities, NULL);
5696                 }
5697         }
5698         if (warning.unused_variable) {
5699                 walk_statements(current_function->statement, check_unused_variables,
5700                                 NULL);
5701         }
5702 }
5703
5704 static int determine_truth(expression_t const* const cond)
5705 {
5706         return
5707                 !is_constant_expression(cond) ? 0 :
5708                 fold_constant(cond) != 0      ? 1 :
5709                 -1;
5710 }
5711
5712 static void check_reachable(statement_t *);
5713 static bool reaches_end;
5714
5715 static bool expression_returns(expression_t const *const expr)
5716 {
5717         switch (expr->kind) {
5718                 case EXPR_CALL: {
5719                         expression_t const *const func = expr->call.function;
5720                         if (func->kind == EXPR_REFERENCE) {
5721                                 entity_t *entity = func->reference.entity;
5722                                 if (entity->kind == ENTITY_FUNCTION
5723                                                 && entity->declaration.modifiers & DM_NORETURN)
5724                                         return false;
5725                         }
5726
5727                         if (!expression_returns(func))
5728                                 return false;
5729
5730                         for (call_argument_t const* arg = expr->call.arguments; arg != NULL; arg = arg->next) {
5731                                 if (!expression_returns(arg->expression))
5732                                         return false;
5733                         }
5734
5735                         return true;
5736                 }
5737
5738                 case EXPR_REFERENCE:
5739                 case EXPR_REFERENCE_ENUM_VALUE:
5740                 case EXPR_CONST:
5741                 case EXPR_CHARACTER_CONSTANT:
5742                 case EXPR_WIDE_CHARACTER_CONSTANT:
5743                 case EXPR_STRING_LITERAL:
5744                 case EXPR_WIDE_STRING_LITERAL:
5745                 case EXPR_COMPOUND_LITERAL: // TODO descend into initialisers
5746                 case EXPR_LABEL_ADDRESS:
5747                 case EXPR_CLASSIFY_TYPE:
5748                 case EXPR_SIZEOF: // TODO handle obscure VLA case
5749                 case EXPR_ALIGNOF:
5750                 case EXPR_FUNCNAME:
5751                 case EXPR_BUILTIN_SYMBOL:
5752                 case EXPR_BUILTIN_CONSTANT_P:
5753                 case EXPR_BUILTIN_PREFETCH:
5754                 case EXPR_OFFSETOF:
5755                 case EXPR_INVALID:
5756                         return true;
5757
5758                 case EXPR_STATEMENT: {
5759                         bool old_reaches_end = reaches_end;
5760                         reaches_end = false;
5761                         check_reachable(expr->statement.statement);
5762                         bool returns = reaches_end;
5763                         reaches_end = old_reaches_end;
5764                         return returns;
5765                 }
5766
5767                 case EXPR_CONDITIONAL:
5768                         // TODO handle constant expression
5769
5770                         if (!expression_returns(expr->conditional.condition))
5771                                 return false;
5772
5773                         if (expr->conditional.true_expression != NULL
5774                                         && expression_returns(expr->conditional.true_expression))
5775                                 return true;
5776
5777                         return expression_returns(expr->conditional.false_expression);
5778
5779                 case EXPR_SELECT:
5780                         return expression_returns(expr->select.compound);
5781
5782                 case EXPR_ARRAY_ACCESS:
5783                         return
5784                                 expression_returns(expr->array_access.array_ref) &&
5785                                 expression_returns(expr->array_access.index);
5786
5787                 case EXPR_VA_START:
5788                         return expression_returns(expr->va_starte.ap);
5789
5790                 case EXPR_VA_ARG:
5791                         return expression_returns(expr->va_arge.ap);
5792
5793                 EXPR_UNARY_CASES_MANDATORY
5794                         return expression_returns(expr->unary.value);
5795
5796                 case EXPR_UNARY_THROW:
5797                         return false;
5798
5799                 EXPR_BINARY_CASES
5800                         // TODO handle constant lhs of && and ||
5801                         return
5802                                 expression_returns(expr->binary.left) &&
5803                                 expression_returns(expr->binary.right);
5804
5805                 case EXPR_UNKNOWN:
5806                         break;
5807         }
5808
5809         panic("unhandled expression");
5810 }
5811
5812 static bool initializer_returns(initializer_t const *const init)
5813 {
5814         switch (init->kind) {
5815                 case INITIALIZER_VALUE:
5816                         return expression_returns(init->value.value);
5817
5818                 case INITIALIZER_LIST: {
5819                         initializer_t * const*       i       = init->list.initializers;
5820                         initializer_t * const* const end     = i + init->list.len;
5821                         bool                         returns = true;
5822                         for (; i != end; ++i) {
5823                                 if (!initializer_returns(*i))
5824                                         returns = false;
5825                         }
5826                         return returns;
5827                 }
5828
5829                 case INITIALIZER_STRING:
5830                 case INITIALIZER_WIDE_STRING:
5831                 case INITIALIZER_DESIGNATOR: // designators have no payload
5832                         return true;
5833         }
5834         panic("unhandled initializer");
5835 }
5836
5837 static bool noreturn_candidate;
5838
5839 static void check_reachable(statement_t *const stmt)
5840 {
5841         if (stmt->base.reachable)
5842                 return;
5843         if (stmt->kind != STATEMENT_DO_WHILE)
5844                 stmt->base.reachable = true;
5845
5846         statement_t *last = stmt;
5847         statement_t *next;
5848         switch (stmt->kind) {
5849                 case STATEMENT_INVALID:
5850                 case STATEMENT_EMPTY:
5851                 case STATEMENT_ASM:
5852                         next = stmt->base.next;
5853                         break;
5854
5855                 case STATEMENT_DECLARATION: {
5856                         declaration_statement_t const *const decl = &stmt->declaration;
5857                         entity_t                const *      ent  = decl->declarations_begin;
5858                         entity_t                const *const last = decl->declarations_end;
5859                         if (ent != NULL) {
5860                                 for (;; ent = ent->base.next) {
5861                                         if (ent->kind                 == ENTITY_VARIABLE &&
5862                                                         ent->variable.initializer != NULL            &&
5863                                                         !initializer_returns(ent->variable.initializer)) {
5864                                                 return;
5865                                         }
5866                                         if (ent == last)
5867                                                 break;
5868                                 }
5869                         }
5870                         next = stmt->base.next;
5871                         break;
5872                 }
5873
5874                 case STATEMENT_COMPOUND:
5875                         next = stmt->compound.statements;
5876                         if (next == NULL)
5877                                 next = stmt->base.next;
5878                         break;
5879
5880                 case STATEMENT_RETURN: {
5881                         expression_t const *const val = stmt->returns.value;
5882                         if (val == NULL || expression_returns(val))
5883                                 noreturn_candidate = false;
5884                         return;
5885                 }
5886
5887                 case STATEMENT_IF: {
5888                         if_statement_t const *const ifs  = &stmt->ifs;
5889                         expression_t   const *const cond = ifs->condition;
5890
5891                         if (!expression_returns(cond))
5892                                 return;
5893
5894                         int const val = determine_truth(cond);
5895
5896                         if (val >= 0)
5897                                 check_reachable(ifs->true_statement);
5898
5899                         if (val > 0)
5900                                 return;
5901
5902                         if (ifs->false_statement != NULL) {
5903                                 check_reachable(ifs->false_statement);
5904                                 return;
5905                         }
5906
5907                         next = stmt->base.next;
5908                         break;
5909                 }
5910
5911                 case STATEMENT_SWITCH: {
5912                         switch_statement_t const *const switchs = &stmt->switchs;
5913                         expression_t       const *const expr    = switchs->expression;
5914
5915                         if (!expression_returns(expr))
5916                                 return;
5917
5918                         if (is_constant_expression(expr)) {
5919                                 long                    const val      = fold_constant(expr);
5920                                 case_label_statement_t *      defaults = NULL;
5921                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5922                                         if (i->expression == NULL) {
5923                                                 defaults = i;
5924                                                 continue;
5925                                         }
5926
5927                                         if (i->first_case <= val && val <= i->last_case) {
5928                                                 check_reachable((statement_t*)i);
5929                                                 return;
5930                                         }
5931                                 }
5932
5933                                 if (defaults != NULL) {
5934                                         check_reachable((statement_t*)defaults);
5935                                         return;
5936                                 }
5937                         } else {
5938                                 bool has_default = false;
5939                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5940                                         if (i->expression == NULL)
5941                                                 has_default = true;
5942
5943                                         check_reachable((statement_t*)i);
5944                                 }
5945
5946                                 if (has_default)
5947                                         return;
5948                         }
5949
5950                         next = stmt->base.next;
5951                         break;
5952                 }
5953
5954                 case STATEMENT_EXPRESSION: {
5955                         /* Check for noreturn function call */
5956                         expression_t const *const expr = stmt->expression.expression;
5957                         if (!expression_returns(expr))
5958                                 return;
5959
5960                         next = stmt->base.next;
5961                         break;
5962                 }
5963
5964                 case STATEMENT_CONTINUE: {
5965                         statement_t *parent = stmt;
5966                         for (;;) {
5967                                 parent = parent->base.parent;
5968                                 if (parent == NULL) /* continue not within loop */
5969                                         return;
5970
5971                                 next = parent;
5972                                 switch (parent->kind) {
5973                                         case STATEMENT_WHILE:    goto continue_while;
5974                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5975                                         case STATEMENT_FOR:      goto continue_for;
5976
5977                                         default: break;
5978                                 }
5979                         }
5980                 }
5981
5982                 case STATEMENT_BREAK: {
5983                         statement_t *parent = stmt;
5984                         for (;;) {
5985                                 parent = parent->base.parent;
5986                                 if (parent == NULL) /* break not within loop/switch */
5987                                         return;
5988
5989                                 switch (parent->kind) {
5990                                         case STATEMENT_SWITCH:
5991                                         case STATEMENT_WHILE:
5992                                         case STATEMENT_DO_WHILE:
5993                                         case STATEMENT_FOR:
5994                                                 last = parent;
5995                                                 next = parent->base.next;
5996                                                 goto found_break_parent;
5997
5998                                         default: break;
5999                                 }
6000                         }
6001 found_break_parent:
6002                         break;
6003                 }
6004
6005                 case STATEMENT_GOTO:
6006                         if (stmt->gotos.expression) {
6007                                 if (!expression_returns(stmt->gotos.expression))
6008                                         return;
6009
6010                                 statement_t *parent = stmt->base.parent;
6011                                 if (parent == NULL) /* top level goto */
6012                                         return;
6013                                 next = parent;
6014                         } else {
6015                                 next = stmt->gotos.label->statement;
6016                                 if (next == NULL) /* missing label */
6017                                         return;
6018                         }
6019                         break;
6020
6021                 case STATEMENT_LABEL:
6022                         next = stmt->label.statement;
6023                         break;
6024
6025                 case STATEMENT_CASE_LABEL:
6026                         next = stmt->case_label.statement;
6027                         break;
6028
6029                 case STATEMENT_WHILE: {
6030                         while_statement_t const *const whiles = &stmt->whiles;
6031                         expression_t      const *const cond   = whiles->condition;
6032
6033                         if (!expression_returns(cond))
6034                                 return;
6035
6036                         int const val = determine_truth(cond);
6037
6038                         if (val >= 0)
6039                                 check_reachable(whiles->body);
6040
6041                         if (val > 0)
6042                                 return;
6043
6044                         next = stmt->base.next;
6045                         break;
6046                 }
6047
6048                 case STATEMENT_DO_WHILE:
6049                         next = stmt->do_while.body;
6050                         break;
6051
6052                 case STATEMENT_FOR: {
6053                         for_statement_t *const fors = &stmt->fors;
6054
6055                         if (fors->condition_reachable)
6056                                 return;
6057                         fors->condition_reachable = true;
6058
6059                         expression_t const *const cond = fors->condition;
6060
6061                         int val;
6062                         if (cond == NULL) {
6063                                 val = 1;
6064                         } else if (expression_returns(cond)) {
6065                                 val = determine_truth(cond);
6066                         } else {
6067                                 return;
6068                         }
6069
6070                         if (val >= 0)
6071                                 check_reachable(fors->body);
6072
6073                         if (val > 0)
6074                                 return;
6075
6076                         next = stmt->base.next;
6077                         break;
6078                 }
6079
6080                 case STATEMENT_MS_TRY: {
6081                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
6082                         check_reachable(ms_try->try_statement);
6083                         next = ms_try->final_statement;
6084                         break;
6085                 }
6086
6087                 case STATEMENT_LEAVE: {
6088                         statement_t *parent = stmt;
6089                         for (;;) {
6090                                 parent = parent->base.parent;
6091                                 if (parent == NULL) /* __leave not within __try */
6092                                         return;
6093
6094                                 if (parent->kind == STATEMENT_MS_TRY) {
6095                                         last = parent;
6096                                         next = parent->ms_try.final_statement;
6097                                         break;
6098                                 }
6099                         }
6100                         break;
6101                 }
6102
6103                 default:
6104                         panic("invalid statement kind");
6105         }
6106
6107         while (next == NULL) {
6108                 next = last->base.parent;
6109                 if (next == NULL) {
6110                         noreturn_candidate = false;
6111
6112                         type_t *const type = current_function->base.type;
6113                         assert(is_type_function(type));
6114                         type_t *const ret  = skip_typeref(type->function.return_type);
6115                         if (warning.return_type                    &&
6116                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
6117                             is_type_valid(ret)                     &&
6118                             !is_sym_main(current_function->base.base.symbol)) {
6119                                 warningf(&stmt->base.source_position,
6120                                          "control reaches end of non-void function");
6121                         }
6122                         return;
6123                 }
6124
6125                 switch (next->kind) {
6126                         case STATEMENT_INVALID:
6127                         case STATEMENT_EMPTY:
6128                         case STATEMENT_DECLARATION:
6129                         case STATEMENT_EXPRESSION:
6130                         case STATEMENT_ASM:
6131                         case STATEMENT_RETURN:
6132                         case STATEMENT_CONTINUE:
6133                         case STATEMENT_BREAK:
6134                         case STATEMENT_GOTO:
6135                         case STATEMENT_LEAVE:
6136                                 panic("invalid control flow in function");
6137
6138                         case STATEMENT_COMPOUND:
6139                                 if (next->compound.stmt_expr) {
6140                                         reaches_end = true;
6141                                         return;
6142                                 }
6143                                 /* FALLTHROUGH */
6144                         case STATEMENT_IF:
6145                         case STATEMENT_SWITCH:
6146                         case STATEMENT_LABEL:
6147                         case STATEMENT_CASE_LABEL:
6148                                 last = next;
6149                                 next = next->base.next;
6150                                 break;
6151
6152                         case STATEMENT_WHILE: {
6153 continue_while:
6154                                 if (next->base.reachable)
6155                                         return;
6156                                 next->base.reachable = true;
6157
6158                                 while_statement_t const *const whiles = &next->whiles;
6159                                 expression_t      const *const cond   = whiles->condition;
6160
6161                                 if (!expression_returns(cond))
6162                                         return;
6163
6164                                 int const val = determine_truth(cond);
6165
6166                                 if (val >= 0)
6167                                         check_reachable(whiles->body);
6168
6169                                 if (val > 0)
6170                                         return;
6171
6172                                 last = next;
6173                                 next = next->base.next;
6174                                 break;
6175                         }
6176
6177                         case STATEMENT_DO_WHILE: {
6178 continue_do_while:
6179                                 if (next->base.reachable)
6180                                         return;
6181                                 next->base.reachable = true;
6182
6183                                 do_while_statement_t const *const dw   = &next->do_while;
6184                                 expression_t         const *const cond = dw->condition;
6185
6186                                 if (!expression_returns(cond))
6187                                         return;
6188
6189                                 int const val = determine_truth(cond);
6190
6191                                 if (val >= 0)
6192                                         check_reachable(dw->body);
6193
6194                                 if (val > 0)
6195                                         return;
6196
6197                                 last = next;
6198                                 next = next->base.next;
6199                                 break;
6200                         }
6201
6202                         case STATEMENT_FOR: {
6203 continue_for:;
6204                                 for_statement_t *const fors = &next->fors;
6205
6206                                 fors->step_reachable = true;
6207
6208                                 if (fors->condition_reachable)
6209                                         return;
6210                                 fors->condition_reachable = true;
6211
6212                                 expression_t const *const cond = fors->condition;
6213
6214                                 int val;
6215                                 if (cond == NULL) {
6216                                         val = 1;
6217                                 } else if (expression_returns(cond)) {
6218                                         val = determine_truth(cond);
6219                                 } else {
6220                                         return;
6221                                 }
6222
6223                                 if (val >= 0)
6224                                         check_reachable(fors->body);
6225
6226                                 if (val > 0)
6227                                         return;
6228
6229                                 last = next;
6230                                 next = next->base.next;
6231                                 break;
6232                         }
6233
6234                         case STATEMENT_MS_TRY:
6235                                 last = next;
6236                                 next = next->ms_try.final_statement;
6237                                 break;
6238                 }
6239         }
6240
6241         check_reachable(next);
6242 }
6243
6244 static void check_unreachable(statement_t* const stmt, void *const env)
6245 {
6246         (void)env;
6247
6248         switch (stmt->kind) {
6249                 case STATEMENT_DO_WHILE:
6250                         if (!stmt->base.reachable) {
6251                                 expression_t const *const cond = stmt->do_while.condition;
6252                                 if (determine_truth(cond) >= 0) {
6253                                         warningf(&cond->base.source_position,
6254                                                  "condition of do-while-loop is unreachable");
6255                                 }
6256                         }
6257                         return;
6258
6259                 case STATEMENT_FOR: {
6260                         for_statement_t const* const fors = &stmt->fors;
6261
6262                         // if init and step are unreachable, cond is unreachable, too
6263                         if (!stmt->base.reachable && !fors->step_reachable) {
6264                                 warningf(&stmt->base.source_position, "statement is unreachable");
6265                         } else {
6266                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
6267                                         warningf(&fors->initialisation->base.source_position,
6268                                                  "initialisation of for-statement is unreachable");
6269                                 }
6270
6271                                 if (!fors->condition_reachable && fors->condition != NULL) {
6272                                         warningf(&fors->condition->base.source_position,
6273                                                  "condition of for-statement is unreachable");
6274                                 }
6275
6276                                 if (!fors->step_reachable && fors->step != NULL) {
6277                                         warningf(&fors->step->base.source_position,
6278                                                  "step of for-statement is unreachable");
6279                                 }
6280                         }
6281                         return;
6282                 }
6283
6284                 case STATEMENT_COMPOUND:
6285                         if (stmt->compound.statements != NULL)
6286                                 return;
6287                         goto warn_unreachable;
6288
6289                 case STATEMENT_DECLARATION: {
6290                         /* Only warn if there is at least one declarator with an initializer.
6291                          * This typically occurs in switch statements. */
6292                         declaration_statement_t const *const decl = &stmt->declaration;
6293                         entity_t                const *      ent  = decl->declarations_begin;
6294                         entity_t                const *const last = decl->declarations_end;
6295                         if (ent != NULL) {
6296                                 for (;; ent = ent->base.next) {
6297                                         if (ent->kind                 == ENTITY_VARIABLE &&
6298                                                         ent->variable.initializer != NULL) {
6299                                                 goto warn_unreachable;
6300                                         }
6301                                         if (ent == last)
6302                                                 return;
6303                                 }
6304                         }
6305                 }
6306
6307                 default:
6308 warn_unreachable:
6309                         if (!stmt->base.reachable)
6310                                 warningf(&stmt->base.source_position, "statement is unreachable");
6311                         return;
6312         }
6313 }
6314
6315 static void parse_external_declaration(void)
6316 {
6317         /* function-definitions and declarations both start with declaration
6318          * specifiers */
6319         declaration_specifiers_t specifiers;
6320         memset(&specifiers, 0, sizeof(specifiers));
6321
6322         add_anchor_token(';');
6323         parse_declaration_specifiers(&specifiers);
6324         rem_anchor_token(';');
6325
6326         /* must be a declaration */
6327         if (token.type == ';') {
6328                 parse_anonymous_declaration_rest(&specifiers);
6329                 return;
6330         }
6331
6332         add_anchor_token(',');
6333         add_anchor_token('=');
6334         add_anchor_token(';');
6335         add_anchor_token('{');
6336
6337         /* declarator is common to both function-definitions and declarations */
6338         entity_t *ndeclaration = parse_declarator(&specifiers, DECL_FLAGS_NONE);
6339
6340         rem_anchor_token('{');
6341         rem_anchor_token(';');
6342         rem_anchor_token('=');
6343         rem_anchor_token(',');
6344
6345         /* must be a declaration */
6346         switch (token.type) {
6347                 case ',':
6348                 case ';':
6349                 case '=':
6350                         parse_declaration_rest(ndeclaration, &specifiers, record_entity,
6351                                         DECL_FLAGS_NONE);
6352                         return;
6353         }
6354
6355         /* must be a function definition */
6356         parse_kr_declaration_list(ndeclaration);
6357
6358         if (token.type != '{') {
6359                 parse_error_expected("while parsing function definition", '{', NULL);
6360                 eat_until_matching_token(';');
6361                 return;
6362         }
6363
6364         assert(is_declaration(ndeclaration));
6365         type_t *type = skip_typeref(ndeclaration->declaration.type);
6366
6367         if (!is_type_function(type)) {
6368                 if (is_type_valid(type)) {
6369                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
6370                                type, ndeclaration->base.symbol);
6371                 }
6372                 eat_block();
6373                 return;
6374         }
6375
6376         if (warning.aggregate_return &&
6377             is_type_compound(skip_typeref(type->function.return_type))) {
6378                 warningf(HERE, "function '%Y' returns an aggregate",
6379                          ndeclaration->base.symbol);
6380         }
6381         if (warning.traditional && !type->function.unspecified_parameters) {
6382                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
6383                         ndeclaration->base.symbol);
6384         }
6385         if (warning.old_style_definition && type->function.unspecified_parameters) {
6386                 warningf(HERE, "old-style function definition '%Y'",
6387                         ndeclaration->base.symbol);
6388         }
6389
6390         /* § 6.7.5.3:14 a function definition with () means no
6391          * parameters (and not unspecified parameters) */
6392         if (type->function.unspecified_parameters &&
6393                         type->function.parameters == NULL     &&
6394                         !type->function.kr_style_parameters) {
6395                 type_t *copy                          = duplicate_type(type);
6396                 copy->function.unspecified_parameters = false;
6397                 type                                  = identify_new_type(copy);
6398
6399                 ndeclaration->declaration.type = type;
6400         }
6401
6402         entity_t *const entity = record_entity(ndeclaration, true);
6403         assert(entity->kind == ENTITY_FUNCTION);
6404         assert(ndeclaration->kind == ENTITY_FUNCTION);
6405
6406         function_t *function = &entity->function;
6407         if (ndeclaration != entity) {
6408                 function->parameters = ndeclaration->function.parameters;
6409         }
6410         assert(is_declaration(entity));
6411         type = skip_typeref(entity->declaration.type);
6412
6413         /* push function parameters and switch scope */
6414         size_t const  top       = environment_top();
6415         scope_t      *old_scope = scope_push(&function->parameters);
6416
6417         entity_t *parameter = function->parameters.entities;
6418         for (; parameter != NULL; parameter = parameter->base.next) {
6419                 if (parameter->base.parent_scope == &ndeclaration->function.parameters) {
6420                         parameter->base.parent_scope = current_scope;
6421                 }
6422                 assert(parameter->base.parent_scope == NULL
6423                                 || parameter->base.parent_scope == current_scope);
6424                 parameter->base.parent_scope = current_scope;
6425                 if (parameter->base.symbol == NULL) {
6426                         errorf(&parameter->base.source_position, "parameter name omitted");
6427                         continue;
6428                 }
6429                 environment_push(parameter);
6430         }
6431
6432         if (function->statement != NULL) {
6433                 parser_error_multiple_definition(entity, HERE);
6434                 eat_block();
6435         } else {
6436                 /* parse function body */
6437                 int         label_stack_top      = label_top();
6438                 function_t *old_current_function = current_function;
6439                 current_function                 = function;
6440                 current_parent                   = NULL;
6441
6442                 goto_first   = NULL;
6443                 goto_anchor  = &goto_first;
6444                 label_first  = NULL;
6445                 label_anchor = &label_first;
6446
6447                 statement_t *const body = parse_compound_statement(false);
6448                 function->statement = body;
6449                 first_err = true;
6450                 check_labels();
6451                 check_declarations();
6452                 if (warning.return_type      ||
6453                     warning.unreachable_code ||
6454                     (warning.missing_noreturn
6455                      && !(function->base.modifiers & DM_NORETURN))) {
6456                         noreturn_candidate = true;
6457                         check_reachable(body);
6458                         if (warning.unreachable_code)
6459                                 walk_statements(body, check_unreachable, NULL);
6460                         if (warning.missing_noreturn &&
6461                             noreturn_candidate       &&
6462                             !(function->base.modifiers & DM_NORETURN)) {
6463                                 warningf(&body->base.source_position,
6464                                          "function '%#T' is candidate for attribute 'noreturn'",
6465                                          type, entity->base.symbol);
6466                         }
6467                 }
6468
6469                 assert(current_parent   == NULL);
6470                 assert(current_function == function);
6471                 current_function = old_current_function;
6472                 label_pop_to(label_stack_top);
6473         }
6474
6475         assert(current_scope == &function->parameters);
6476         scope_pop(old_scope);
6477         environment_pop_to(top);
6478 }
6479
6480 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
6481                                   source_position_t *source_position,
6482                                   const symbol_t *symbol)
6483 {
6484         type_t *type = allocate_type_zero(TYPE_BITFIELD);
6485
6486         type->bitfield.base_type       = base_type;
6487         type->bitfield.size_expression = size;
6488
6489         il_size_t bit_size;
6490         type_t *skipped_type = skip_typeref(base_type);
6491         if (!is_type_integer(skipped_type)) {
6492                 errorf(HERE, "bitfield base type '%T' is not an integer type",
6493                         base_type);
6494                 bit_size = 0;
6495         } else {
6496                 bit_size = skipped_type->base.size * 8;
6497         }
6498
6499         if (is_constant_expression(size)) {
6500                 long v = fold_constant(size);
6501
6502                 if (v < 0) {
6503                         errorf(source_position, "negative width in bit-field '%Y'", symbol);
6504                 } else if (v == 0) {
6505                         errorf(source_position, "zero width for bit-field '%Y'", symbol);
6506                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
6507                         errorf(source_position, "width of '%Y' exceeds its type", symbol);
6508                 } else {
6509                         type->bitfield.bit_size = v;
6510                 }
6511         }
6512
6513         return type;
6514 }
6515
6516 static entity_t *find_compound_entry(compound_t *compound, symbol_t *symbol)
6517 {
6518         entity_t *iter = compound->members.entities;
6519         for (; iter != NULL; iter = iter->base.next) {
6520                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
6521                         continue;
6522
6523                 if (iter->base.symbol == symbol) {
6524                         return iter;
6525                 } else if (iter->base.symbol == NULL) {
6526                         type_t *type = skip_typeref(iter->declaration.type);
6527                         if (is_type_compound(type)) {
6528                                 entity_t *result
6529                                         = find_compound_entry(type->compound.compound, symbol);
6530                                 if (result != NULL)
6531                                         return result;
6532                         }
6533                         continue;
6534                 }
6535         }
6536
6537         return NULL;
6538 }
6539
6540 static void parse_compound_declarators(compound_t *compound,
6541                 const declaration_specifiers_t *specifiers)
6542 {
6543         while (true) {
6544                 entity_t *entity;
6545
6546                 if (token.type == ':') {
6547                         source_position_t source_position = *HERE;
6548                         next_token();
6549
6550                         type_t *base_type = specifiers->type;
6551                         expression_t *size = parse_constant_expression();
6552
6553                         type_t *type = make_bitfield_type(base_type, size,
6554                                         &source_position, sym_anonymous);
6555
6556                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
6557                         entity->base.namespc                       = NAMESPACE_NORMAL;
6558                         entity->base.source_position               = source_position;
6559                         entity->declaration.declared_storage_class = STORAGE_CLASS_NONE;
6560                         entity->declaration.storage_class          = STORAGE_CLASS_NONE;
6561                         entity->declaration.modifiers              = specifiers->modifiers;
6562                         entity->declaration.type                   = type;
6563                         append_entity(&compound->members, entity);
6564                 } else {
6565                         entity = parse_declarator(specifiers,
6566                                         DECL_MAY_BE_ABSTRACT | DECL_CREATE_COMPOUND_MEMBER);
6567                         if (entity->kind == ENTITY_TYPEDEF) {
6568                                 errorf(&entity->base.source_position,
6569                                                 "typedef not allowed as compound member");
6570                         } else {
6571                                 assert(entity->kind == ENTITY_COMPOUND_MEMBER);
6572
6573                                 /* make sure we don't define a symbol multiple times */
6574                                 symbol_t *symbol = entity->base.symbol;
6575                                 if (symbol != NULL) {
6576                                         entity_t *prev = find_compound_entry(compound, symbol);
6577                                         if (prev != NULL) {
6578                                                 errorf(&entity->base.source_position,
6579                                                                 "multiple declarations of symbol '%Y' (declared %P)",
6580                                                                 symbol, &prev->base.source_position);
6581                                         }
6582                                 }
6583
6584                                 if (token.type == ':') {
6585                                         source_position_t source_position = *HERE;
6586                                         next_token();
6587                                         expression_t *size = parse_constant_expression();
6588
6589                                         type_t *type          = entity->declaration.type;
6590                                         type_t *bitfield_type = make_bitfield_type(type, size,
6591                                                         &source_position, entity->base.symbol);
6592                                         entity->declaration.type = bitfield_type;
6593                                 } else {
6594                                         type_t *orig_type = entity->declaration.type;
6595                                         type_t *type      = skip_typeref(orig_type);
6596                                         if (is_type_function(type)) {
6597                                                 errorf(&entity->base.source_position,
6598                                                                 "compound member '%Y' must not have function type '%T'",
6599                                                                 entity->base.symbol, orig_type);
6600                                         } else if (is_type_incomplete(type)) {
6601                                                 /* §6.7.2.1:16 flexible array member */
6602                                                 if (is_type_array(type) &&
6603                                                                 token.type == ';'   &&
6604                                                                 look_ahead(1)->type == '}') {
6605                                                         compound->has_flexible_member = true;
6606                                                 } else {
6607                                                         errorf(&entity->base.source_position,
6608                                                                         "compound member '%Y' has incomplete type '%T'",
6609                                                                         entity->base.symbol, orig_type);
6610                                                 }
6611                                         }
6612                                 }
6613
6614                                 append_entity(&compound->members, entity);
6615                         }
6616                 }
6617
6618                 if (token.type != ',')
6619                         break;
6620                 next_token();
6621         }
6622         expect(';', end_error);
6623
6624 end_error:
6625         anonymous_entity = NULL;
6626 }
6627
6628 static void parse_compound_type_entries(compound_t *compound)
6629 {
6630         eat('{');
6631         add_anchor_token('}');
6632
6633         while (token.type != '}') {
6634                 if (token.type == T_EOF) {
6635                         errorf(HERE, "EOF while parsing struct");
6636                         break;
6637                 }
6638                 declaration_specifiers_t specifiers;
6639                 memset(&specifiers, 0, sizeof(specifiers));
6640                 parse_declaration_specifiers(&specifiers);
6641
6642                 parse_compound_declarators(compound, &specifiers);
6643         }
6644         rem_anchor_token('}');
6645         next_token();
6646
6647         /* §6.7.2.1:7 */
6648         compound->complete = true;
6649 }
6650
6651 static type_t *parse_typename(void)
6652 {
6653         declaration_specifiers_t specifiers;
6654         memset(&specifiers, 0, sizeof(specifiers));
6655         parse_declaration_specifiers(&specifiers);
6656         if (specifiers.storage_class != STORAGE_CLASS_NONE ||
6657                         specifiers.thread_local) {
6658                 /* TODO: improve error message, user does probably not know what a
6659                  * storage class is...
6660                  */
6661                 errorf(HERE, "typename may not have a storage class");
6662         }
6663
6664         type_t *result = parse_abstract_declarator(specifiers.type);
6665
6666         return result;
6667 }
6668
6669
6670
6671
6672 typedef expression_t* (*parse_expression_function)(void);
6673 typedef expression_t* (*parse_expression_infix_function)(expression_t *left);
6674
6675 typedef struct expression_parser_function_t expression_parser_function_t;
6676 struct expression_parser_function_t {
6677         parse_expression_function        parser;
6678         precedence_t                     infix_precedence;
6679         parse_expression_infix_function  infix_parser;
6680 };
6681
6682 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
6683
6684 /**
6685  * Prints an error message if an expression was expected but not read
6686  */
6687 static expression_t *expected_expression_error(void)
6688 {
6689         /* skip the error message if the error token was read */
6690         if (token.type != T_ERROR) {
6691                 errorf(HERE, "expected expression, got token %K", &token);
6692         }
6693         next_token();
6694
6695         return create_invalid_expression();
6696 }
6697
6698 /**
6699  * Parse a string constant.
6700  */
6701 static expression_t *parse_string_const(void)
6702 {
6703         wide_string_t wres;
6704         if (token.type == T_STRING_LITERAL) {
6705                 string_t res = token.v.string;
6706                 next_token();
6707                 while (token.type == T_STRING_LITERAL) {
6708                         res = concat_strings(&res, &token.v.string);
6709                         next_token();
6710                 }
6711                 if (token.type != T_WIDE_STRING_LITERAL) {
6712                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
6713                         /* note: that we use type_char_ptr here, which is already the
6714                          * automatic converted type. revert_automatic_type_conversion
6715                          * will construct the array type */
6716                         cnst->base.type    = warning.write_strings ? type_const_char_ptr : type_char_ptr;
6717                         cnst->string.value = res;
6718                         return cnst;
6719                 }
6720
6721                 wres = concat_string_wide_string(&res, &token.v.wide_string);
6722         } else {
6723                 wres = token.v.wide_string;
6724         }
6725         next_token();
6726
6727         for (;;) {
6728                 switch (token.type) {
6729                         case T_WIDE_STRING_LITERAL:
6730                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
6731                                 break;
6732
6733                         case T_STRING_LITERAL:
6734                                 wres = concat_wide_string_string(&wres, &token.v.string);
6735                                 break;
6736
6737                         default: {
6738                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
6739                                 cnst->base.type         = warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
6740                                 cnst->wide_string.value = wres;
6741                                 return cnst;
6742                         }
6743                 }
6744                 next_token();
6745         }
6746 }
6747
6748 /**
6749  * Parse a boolean constant.
6750  */
6751 static expression_t *parse_bool_const(bool value)
6752 {
6753         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6754         cnst->base.type          = type_bool;
6755         cnst->conste.v.int_value = value;
6756
6757         next_token();
6758
6759         return cnst;
6760 }
6761
6762 /**
6763  * Parse an integer constant.
6764  */
6765 static expression_t *parse_int_const(void)
6766 {
6767         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6768         cnst->base.type          = token.datatype;
6769         cnst->conste.v.int_value = token.v.intvalue;
6770
6771         next_token();
6772
6773         return cnst;
6774 }
6775
6776 /**
6777  * Parse a character constant.
6778  */
6779 static expression_t *parse_character_constant(void)
6780 {
6781         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
6782         cnst->base.type          = token.datatype;
6783         cnst->conste.v.character = token.v.string;
6784
6785         if (cnst->conste.v.character.size != 1) {
6786                 if (!GNU_MODE) {
6787                         errorf(HERE, "more than 1 character in character constant");
6788                 } else if (warning.multichar) {
6789                         warningf(HERE, "multi-character character constant");
6790                 }
6791         }
6792         next_token();
6793
6794         return cnst;
6795 }
6796
6797 /**
6798  * Parse a wide character constant.
6799  */
6800 static expression_t *parse_wide_character_constant(void)
6801 {
6802         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
6803         cnst->base.type               = token.datatype;
6804         cnst->conste.v.wide_character = token.v.wide_string;
6805
6806         if (cnst->conste.v.wide_character.size != 1) {
6807                 if (!GNU_MODE) {
6808                         errorf(HERE, "more than 1 character in character constant");
6809                 } else if (warning.multichar) {
6810                         warningf(HERE, "multi-character character constant");
6811                 }
6812         }
6813         next_token();
6814
6815         return cnst;
6816 }
6817
6818 /**
6819  * Parse a float constant.
6820  */
6821 static expression_t *parse_float_const(void)
6822 {
6823         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6824         cnst->base.type            = token.datatype;
6825         cnst->conste.v.float_value = token.v.floatvalue;
6826
6827         next_token();
6828
6829         return cnst;
6830 }
6831
6832 static entity_t *create_implicit_function(symbol_t *symbol,
6833                 const source_position_t *source_position)
6834 {
6835         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION);
6836         ntype->function.return_type            = type_int;
6837         ntype->function.unspecified_parameters = true;
6838         ntype->function.linkage                = LINKAGE_C;
6839         type_t *type                           = identify_new_type(ntype);
6840
6841         entity_t *entity = allocate_entity_zero(ENTITY_FUNCTION);
6842         entity->declaration.storage_class          = STORAGE_CLASS_EXTERN;
6843         entity->declaration.declared_storage_class = STORAGE_CLASS_EXTERN;
6844         entity->declaration.type                   = type;
6845         entity->declaration.implicit               = true;
6846         entity->base.symbol                        = symbol;
6847         entity->base.source_position               = *source_position;
6848
6849         bool strict_prototypes_old = warning.strict_prototypes;
6850         warning.strict_prototypes  = false;
6851         record_entity(entity, false);
6852         warning.strict_prototypes = strict_prototypes_old;
6853
6854         return entity;
6855 }
6856
6857 /**
6858  * Creates a return_type (func)(argument_type) function type if not
6859  * already exists.
6860  */
6861 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
6862                                     type_t *argument_type2)
6863 {
6864         function_parameter_t *parameter2
6865                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
6866         memset(parameter2, 0, sizeof(parameter2[0]));
6867         parameter2->type = argument_type2;
6868
6869         function_parameter_t *parameter1
6870                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
6871         memset(parameter1, 0, sizeof(parameter1[0]));
6872         parameter1->type = argument_type1;
6873         parameter1->next = parameter2;
6874
6875         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6876         type->function.return_type = return_type;
6877         type->function.parameters  = parameter1;
6878
6879         return identify_new_type(type);
6880 }
6881
6882 /**
6883  * Creates a return_type (func)(argument_type) function type if not
6884  * already exists.
6885  *
6886  * @param return_type    the return type
6887  * @param argument_type  the argument type
6888  */
6889 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
6890 {
6891         function_parameter_t *parameter
6892                 = obstack_alloc(type_obst, sizeof(parameter[0]));
6893         memset(parameter, 0, sizeof(parameter[0]));
6894         parameter->type = argument_type;
6895
6896         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6897         type->function.return_type = return_type;
6898         type->function.parameters  = parameter;
6899
6900         return identify_new_type(type);
6901 }
6902
6903 static type_t *make_function_0_type(type_t *return_type)
6904 {
6905         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6906         type->function.return_type = return_type;
6907         type->function.parameters  = NULL;
6908
6909         return identify_new_type(type);
6910 }
6911
6912 /**
6913  * Creates a function type for some function like builtins.
6914  *
6915  * @param symbol   the symbol describing the builtin
6916  */
6917 static type_t *get_builtin_symbol_type(symbol_t *symbol)
6918 {
6919         switch (symbol->ID) {
6920         case T___builtin_alloca:
6921                 return make_function_1_type(type_void_ptr, type_size_t);
6922         case T___builtin_huge_val:
6923                 return make_function_0_type(type_double);
6924         case T___builtin_inf:
6925                 return make_function_0_type(type_double);
6926         case T___builtin_inff:
6927                 return make_function_0_type(type_float);
6928         case T___builtin_infl:
6929                 return make_function_0_type(type_long_double);
6930         case T___builtin_nan:
6931                 return make_function_1_type(type_double, type_char_ptr);
6932         case T___builtin_nanf:
6933                 return make_function_1_type(type_float, type_char_ptr);
6934         case T___builtin_nanl:
6935                 return make_function_1_type(type_long_double, type_char_ptr);
6936         case T___builtin_va_end:
6937                 return make_function_1_type(type_void, type_valist);
6938         case T___builtin_expect:
6939                 return make_function_2_type(type_long, type_long, type_long);
6940         default:
6941                 internal_errorf(HERE, "not implemented builtin identifier found");
6942         }
6943 }
6944
6945 /**
6946  * Performs automatic type cast as described in § 6.3.2.1.
6947  *
6948  * @param orig_type  the original type
6949  */
6950 static type_t *automatic_type_conversion(type_t *orig_type)
6951 {
6952         type_t *type = skip_typeref(orig_type);
6953         if (is_type_array(type)) {
6954                 array_type_t *array_type   = &type->array;
6955                 type_t       *element_type = array_type->element_type;
6956                 unsigned      qualifiers   = array_type->base.qualifiers;
6957
6958                 return make_pointer_type(element_type, qualifiers);
6959         }
6960
6961         if (is_type_function(type)) {
6962                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6963         }
6964
6965         return orig_type;
6966 }
6967
6968 /**
6969  * reverts the automatic casts of array to pointer types and function
6970  * to function-pointer types as defined § 6.3.2.1
6971  */
6972 type_t *revert_automatic_type_conversion(const expression_t *expression)
6973 {
6974         switch (expression->kind) {
6975                 case EXPR_REFERENCE: {
6976                         entity_t *entity = expression->reference.entity;
6977                         if (is_declaration(entity)) {
6978                                 return entity->declaration.type;
6979                         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6980                                 return entity->enum_value.enum_type;
6981                         } else {
6982                                 panic("no declaration or enum in reference");
6983                         }
6984                 }
6985
6986                 case EXPR_SELECT: {
6987                         entity_t *entity = expression->select.compound_entry;
6988                         assert(is_declaration(entity));
6989                         type_t   *type   = entity->declaration.type;
6990                         return get_qualified_type(type,
6991                                         expression->base.type->base.qualifiers);
6992                 }
6993
6994                 case EXPR_UNARY_DEREFERENCE: {
6995                         const expression_t *const value = expression->unary.value;
6996                         type_t             *const type  = skip_typeref(value->base.type);
6997                         if (!is_type_pointer(type))
6998                                 return type_error_type;
6999                         return type->pointer.points_to;
7000                 }
7001
7002                 case EXPR_BUILTIN_SYMBOL:
7003                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
7004
7005                 case EXPR_ARRAY_ACCESS: {
7006                         const expression_t *array_ref = expression->array_access.array_ref;
7007                         type_t             *type_left = skip_typeref(array_ref->base.type);
7008                         if (!is_type_pointer(type_left))
7009                                 return type_error_type;
7010                         return type_left->pointer.points_to;
7011                 }
7012
7013                 case EXPR_STRING_LITERAL: {
7014                         size_t size = expression->string.value.size;
7015                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
7016                 }
7017
7018                 case EXPR_WIDE_STRING_LITERAL: {
7019                         size_t size = expression->wide_string.value.size;
7020                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
7021                 }
7022
7023                 case EXPR_COMPOUND_LITERAL:
7024                         return expression->compound_literal.type;
7025
7026                 default:
7027                         return expression->base.type;
7028         }
7029 }
7030
7031 static expression_t *parse_reference(void)
7032 {
7033         symbol_t *const symbol = token.v.symbol;
7034
7035         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
7036
7037         if (entity == NULL) {
7038                 if (!strict_mode && look_ahead(1)->type == '(') {
7039                         /* an implicitly declared function */
7040                         if (warning.error_implicit_function_declaration) {
7041                                 errorf(HERE, "implicit declaration of function '%Y'", symbol);
7042                         } else if (warning.implicit_function_declaration) {
7043                                 warningf(HERE, "implicit declaration of function '%Y'", symbol);
7044                         }
7045
7046                         entity = create_implicit_function(symbol, HERE);
7047                 } else {
7048                         errorf(HERE, "unknown identifier '%Y' found.", symbol);
7049                         entity = create_error_entity(symbol, ENTITY_VARIABLE);
7050                 }
7051         }
7052
7053         type_t *orig_type;
7054
7055         if (is_declaration(entity)) {
7056                 orig_type = entity->declaration.type;
7057         } else if (entity->kind == ENTITY_ENUM_VALUE) {
7058                 orig_type = entity->enum_value.enum_type;
7059         } else if (entity->kind == ENTITY_TYPEDEF) {
7060                 errorf(HERE, "encountered typedef name '%Y' while parsing expression",
7061                         symbol);
7062                 next_token();
7063                 return create_invalid_expression();
7064         } else {
7065                 panic("expected declaration or enum value in reference");
7066         }
7067
7068         /* we always do the auto-type conversions; the & and sizeof parser contains
7069          * code to revert this! */
7070         type_t *type = automatic_type_conversion(orig_type);
7071
7072         expression_kind_t kind = EXPR_REFERENCE;
7073         if (entity->kind == ENTITY_ENUM_VALUE)
7074                 kind = EXPR_REFERENCE_ENUM_VALUE;
7075
7076         expression_t *expression     = allocate_expression_zero(kind);
7077         expression->reference.entity = entity;
7078         expression->base.type        = type;
7079
7080         /* this declaration is used */
7081         if (is_declaration(entity)) {
7082                 entity->declaration.used = true;
7083         }
7084
7085         if (entity->base.parent_scope != file_scope
7086                 && entity->base.parent_scope->depth < current_function->parameters.depth
7087                 && is_type_valid(orig_type) && !is_type_function(orig_type)) {
7088                 if (entity->kind == ENTITY_VARIABLE) {
7089                         /* access of a variable from an outer function */
7090                         entity->variable.address_taken = true;
7091                 } else if (entity->kind == ENTITY_PARAMETER) {
7092                         entity->parameter.address_taken = true;
7093                 }
7094                 current_function->need_closure = true;
7095         }
7096
7097         /* check for deprecated functions */
7098         if (warning.deprecated_declarations
7099                 && is_declaration(entity)
7100                 && entity->declaration.modifiers & DM_DEPRECATED) {
7101                 declaration_t *declaration = &entity->declaration;
7102
7103                 char const *const prefix = entity->kind == ENTITY_FUNCTION ?
7104                         "function" : "variable";
7105
7106                 if (declaration->deprecated_string != NULL) {
7107                         warningf(HERE, "%s '%Y' is deprecated (declared %P): \"%s\"",
7108                                  prefix, entity->base.symbol, &entity->base.source_position,
7109                                  declaration->deprecated_string);
7110                 } else {
7111                         warningf(HERE, "%s '%Y' is deprecated (declared %P)", prefix,
7112                                  entity->base.symbol, &entity->base.source_position);
7113                 }
7114         }
7115
7116         if (warning.init_self && entity == current_init_decl && !in_type_prop
7117             && entity->kind == ENTITY_VARIABLE) {
7118                 current_init_decl = NULL;
7119                 warningf(HERE, "variable '%#T' is initialized by itself",
7120                          entity->declaration.type, entity->base.symbol);
7121         }
7122
7123         next_token();
7124         return expression;
7125 }
7126
7127 static bool semantic_cast(expression_t *cast)
7128 {
7129         expression_t            *expression      = cast->unary.value;
7130         type_t                  *orig_dest_type  = cast->base.type;
7131         type_t                  *orig_type_right = expression->base.type;
7132         type_t            const *dst_type        = skip_typeref(orig_dest_type);
7133         type_t            const *src_type        = skip_typeref(orig_type_right);
7134         source_position_t const *pos             = &cast->base.source_position;
7135
7136         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
7137         if (dst_type == type_void)
7138                 return true;
7139
7140         /* only integer and pointer can be casted to pointer */
7141         if (is_type_pointer(dst_type)  &&
7142             !is_type_pointer(src_type) &&
7143             !is_type_integer(src_type) &&
7144             is_type_valid(src_type)) {
7145                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
7146                 return false;
7147         }
7148
7149         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
7150                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
7151                 return false;
7152         }
7153
7154         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
7155                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
7156                 return false;
7157         }
7158
7159         if (warning.cast_qual &&
7160             is_type_pointer(src_type) &&
7161             is_type_pointer(dst_type)) {
7162                 type_t *src = skip_typeref(src_type->pointer.points_to);
7163                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
7164                 unsigned missing_qualifiers =
7165                         src->base.qualifiers & ~dst->base.qualifiers;
7166                 if (missing_qualifiers != 0) {
7167                         warningf(pos,
7168                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
7169                                  missing_qualifiers, orig_type_right);
7170                 }
7171         }
7172         return true;
7173 }
7174
7175 static expression_t *parse_compound_literal(type_t *type)
7176 {
7177         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
7178
7179         parse_initializer_env_t env;
7180         env.type             = type;
7181         env.entity           = NULL;
7182         env.must_be_constant = false;
7183         initializer_t *initializer = parse_initializer(&env);
7184         type = env.type;
7185
7186         expression->compound_literal.initializer = initializer;
7187         expression->compound_literal.type        = type;
7188         expression->base.type                    = automatic_type_conversion(type);
7189
7190         return expression;
7191 }
7192
7193 /**
7194  * Parse a cast expression.
7195  */
7196 static expression_t *parse_cast(void)
7197 {
7198         add_anchor_token(')');
7199
7200         source_position_t source_position = token.source_position;
7201
7202         type_t *type = parse_typename();
7203
7204         rem_anchor_token(')');
7205         expect(')', end_error);
7206
7207         if (token.type == '{') {
7208                 return parse_compound_literal(type);
7209         }
7210
7211         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
7212         cast->base.source_position = source_position;
7213
7214         expression_t *value = parse_sub_expression(PREC_CAST);
7215         cast->base.type   = type;
7216         cast->unary.value = value;
7217
7218         if (! semantic_cast(cast)) {
7219                 /* TODO: record the error in the AST. else it is impossible to detect it */
7220         }
7221
7222         return cast;
7223 end_error:
7224         return create_invalid_expression();
7225 }
7226
7227 /**
7228  * Parse a statement expression.
7229  */
7230 static expression_t *parse_statement_expression(void)
7231 {
7232         add_anchor_token(')');
7233
7234         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
7235
7236         statement_t *statement          = parse_compound_statement(true);
7237         statement->compound.stmt_expr   = true;
7238         expression->statement.statement = statement;
7239
7240         /* find last statement and use its type */
7241         type_t *type = type_void;
7242         const statement_t *stmt = statement->compound.statements;
7243         if (stmt != NULL) {
7244                 while (stmt->base.next != NULL)
7245                         stmt = stmt->base.next;
7246
7247                 if (stmt->kind == STATEMENT_EXPRESSION) {
7248                         type = stmt->expression.expression->base.type;
7249                 }
7250         } else if (warning.other) {
7251                 warningf(&expression->base.source_position, "empty statement expression ({})");
7252         }
7253         expression->base.type = type;
7254
7255         rem_anchor_token(')');
7256         expect(')', end_error);
7257
7258 end_error:
7259         return expression;
7260 }
7261
7262 /**
7263  * Parse a parenthesized expression.
7264  */
7265 static expression_t *parse_parenthesized_expression(void)
7266 {
7267         eat('(');
7268
7269         switch (token.type) {
7270         case '{':
7271                 /* gcc extension: a statement expression */
7272                 return parse_statement_expression();
7273
7274         TYPE_QUALIFIERS
7275         TYPE_SPECIFIERS
7276                 return parse_cast();
7277         case T_IDENTIFIER:
7278                 if (is_typedef_symbol(token.v.symbol)) {
7279                         return parse_cast();
7280                 }
7281         }
7282
7283         add_anchor_token(')');
7284         expression_t *result = parse_expression();
7285         result->base.parenthesized = true;
7286         rem_anchor_token(')');
7287         expect(')', end_error);
7288
7289 end_error:
7290         return result;
7291 }
7292
7293 static expression_t *parse_function_keyword(void)
7294 {
7295         /* TODO */
7296
7297         if (current_function == NULL) {
7298                 errorf(HERE, "'__func__' used outside of a function");
7299         }
7300
7301         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7302         expression->base.type     = type_char_ptr;
7303         expression->funcname.kind = FUNCNAME_FUNCTION;
7304
7305         next_token();
7306
7307         return expression;
7308 }
7309
7310 static expression_t *parse_pretty_function_keyword(void)
7311 {
7312         if (current_function == NULL) {
7313                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
7314         }
7315
7316         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7317         expression->base.type     = type_char_ptr;
7318         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
7319
7320         eat(T___PRETTY_FUNCTION__);
7321
7322         return expression;
7323 }
7324
7325 static expression_t *parse_funcsig_keyword(void)
7326 {
7327         if (current_function == NULL) {
7328                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
7329         }
7330
7331         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7332         expression->base.type     = type_char_ptr;
7333         expression->funcname.kind = FUNCNAME_FUNCSIG;
7334
7335         eat(T___FUNCSIG__);
7336
7337         return expression;
7338 }
7339
7340 static expression_t *parse_funcdname_keyword(void)
7341 {
7342         if (current_function == NULL) {
7343                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
7344         }
7345
7346         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7347         expression->base.type     = type_char_ptr;
7348         expression->funcname.kind = FUNCNAME_FUNCDNAME;
7349
7350         eat(T___FUNCDNAME__);
7351
7352         return expression;
7353 }
7354
7355 static designator_t *parse_designator(void)
7356 {
7357         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
7358         result->source_position = *HERE;
7359
7360         if (token.type != T_IDENTIFIER) {
7361                 parse_error_expected("while parsing member designator",
7362                                      T_IDENTIFIER, NULL);
7363                 return NULL;
7364         }
7365         result->symbol = token.v.symbol;
7366         next_token();
7367
7368         designator_t *last_designator = result;
7369         while (true) {
7370                 if (token.type == '.') {
7371                         next_token();
7372                         if (token.type != T_IDENTIFIER) {
7373                                 parse_error_expected("while parsing member designator",
7374                                                      T_IDENTIFIER, NULL);
7375                                 return NULL;
7376                         }
7377                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7378                         designator->source_position = *HERE;
7379                         designator->symbol          = token.v.symbol;
7380                         next_token();
7381
7382                         last_designator->next = designator;
7383                         last_designator       = designator;
7384                         continue;
7385                 }
7386                 if (token.type == '[') {
7387                         next_token();
7388                         add_anchor_token(']');
7389                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7390                         designator->source_position = *HERE;
7391                         designator->array_index     = parse_expression();
7392                         rem_anchor_token(']');
7393                         expect(']', end_error);
7394                         if (designator->array_index == NULL) {
7395                                 return NULL;
7396                         }
7397
7398                         last_designator->next = designator;
7399                         last_designator       = designator;
7400                         continue;
7401                 }
7402                 break;
7403         }
7404
7405         return result;
7406 end_error:
7407         return NULL;
7408 }
7409
7410 /**
7411  * Parse the __builtin_offsetof() expression.
7412  */
7413 static expression_t *parse_offsetof(void)
7414 {
7415         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
7416         expression->base.type    = type_size_t;
7417
7418         eat(T___builtin_offsetof);
7419
7420         expect('(', end_error);
7421         add_anchor_token(',');
7422         type_t *type = parse_typename();
7423         rem_anchor_token(',');
7424         expect(',', end_error);
7425         add_anchor_token(')');
7426         designator_t *designator = parse_designator();
7427         rem_anchor_token(')');
7428         expect(')', end_error);
7429
7430         expression->offsetofe.type       = type;
7431         expression->offsetofe.designator = designator;
7432
7433         type_path_t path;
7434         memset(&path, 0, sizeof(path));
7435         path.top_type = type;
7436         path.path     = NEW_ARR_F(type_path_entry_t, 0);
7437
7438         descend_into_subtype(&path);
7439
7440         if (!walk_designator(&path, designator, true)) {
7441                 return create_invalid_expression();
7442         }
7443
7444         DEL_ARR_F(path.path);
7445
7446         return expression;
7447 end_error:
7448         return create_invalid_expression();
7449 }
7450
7451 /**
7452  * Parses a _builtin_va_start() expression.
7453  */
7454 static expression_t *parse_va_start(void)
7455 {
7456         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
7457
7458         eat(T___builtin_va_start);
7459
7460         expect('(', end_error);
7461         add_anchor_token(',');
7462         expression->va_starte.ap = parse_assignment_expression();
7463         rem_anchor_token(',');
7464         expect(',', end_error);
7465         expression_t *const expr = parse_assignment_expression();
7466         if (expr->kind == EXPR_REFERENCE) {
7467                 entity_t *const entity = expr->reference.entity;
7468                 if (entity->base.parent_scope != &current_function->parameters
7469                                 || entity->base.next != NULL
7470                                 || entity->kind != ENTITY_PARAMETER) {
7471                         errorf(&expr->base.source_position,
7472                                "second argument of 'va_start' must be last parameter of the current function");
7473                 } else {
7474                         expression->va_starte.parameter = &entity->variable;
7475                 }
7476                 expect(')', end_error);
7477                 return expression;
7478         }
7479         expect(')', end_error);
7480 end_error:
7481         return create_invalid_expression();
7482 }
7483
7484 /**
7485  * Parses a _builtin_va_arg() expression.
7486  */
7487 static expression_t *parse_va_arg(void)
7488 {
7489         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
7490
7491         eat(T___builtin_va_arg);
7492
7493         expect('(', end_error);
7494         expression->va_arge.ap = parse_assignment_expression();
7495         expect(',', end_error);
7496         expression->base.type = parse_typename();
7497         expect(')', end_error);
7498
7499         return expression;
7500 end_error:
7501         return create_invalid_expression();
7502 }
7503
7504 static expression_t *parse_builtin_symbol(void)
7505 {
7506         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
7507
7508         symbol_t *symbol = token.v.symbol;
7509
7510         expression->builtin_symbol.symbol = symbol;
7511         next_token();
7512
7513         type_t *type = get_builtin_symbol_type(symbol);
7514         type = automatic_type_conversion(type);
7515
7516         expression->base.type = type;
7517         return expression;
7518 }
7519
7520 /**
7521  * Parses a __builtin_constant() expression.
7522  */
7523 static expression_t *parse_builtin_constant(void)
7524 {
7525         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
7526
7527         eat(T___builtin_constant_p);
7528
7529         expect('(', end_error);
7530         add_anchor_token(')');
7531         expression->builtin_constant.value = parse_assignment_expression();
7532         rem_anchor_token(')');
7533         expect(')', end_error);
7534         expression->base.type = type_int;
7535
7536         return expression;
7537 end_error:
7538         return create_invalid_expression();
7539 }
7540
7541 /**
7542  * Parses a __builtin_prefetch() expression.
7543  */
7544 static expression_t *parse_builtin_prefetch(void)
7545 {
7546         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
7547
7548         eat(T___builtin_prefetch);
7549
7550         expect('(', end_error);
7551         add_anchor_token(')');
7552         expression->builtin_prefetch.adr = parse_assignment_expression();
7553         if (token.type == ',') {
7554                 next_token();
7555                 expression->builtin_prefetch.rw = parse_assignment_expression();
7556         }
7557         if (token.type == ',') {
7558                 next_token();
7559                 expression->builtin_prefetch.locality = parse_assignment_expression();
7560         }
7561         rem_anchor_token(')');
7562         expect(')', end_error);
7563         expression->base.type = type_void;
7564
7565         return expression;
7566 end_error:
7567         return create_invalid_expression();
7568 }
7569
7570 /**
7571  * Parses a __builtin_is_*() compare expression.
7572  */
7573 static expression_t *parse_compare_builtin(void)
7574 {
7575         expression_t *expression;
7576
7577         switch (token.type) {
7578         case T___builtin_isgreater:
7579                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
7580                 break;
7581         case T___builtin_isgreaterequal:
7582                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
7583                 break;
7584         case T___builtin_isless:
7585                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
7586                 break;
7587         case T___builtin_islessequal:
7588                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
7589                 break;
7590         case T___builtin_islessgreater:
7591                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
7592                 break;
7593         case T___builtin_isunordered:
7594                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
7595                 break;
7596         default:
7597                 internal_errorf(HERE, "invalid compare builtin found");
7598         }
7599         expression->base.source_position = *HERE;
7600         next_token();
7601
7602         expect('(', end_error);
7603         expression->binary.left = parse_assignment_expression();
7604         expect(',', end_error);
7605         expression->binary.right = parse_assignment_expression();
7606         expect(')', end_error);
7607
7608         type_t *const orig_type_left  = expression->binary.left->base.type;
7609         type_t *const orig_type_right = expression->binary.right->base.type;
7610
7611         type_t *const type_left  = skip_typeref(orig_type_left);
7612         type_t *const type_right = skip_typeref(orig_type_right);
7613         if (!is_type_float(type_left) && !is_type_float(type_right)) {
7614                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7615                         type_error_incompatible("invalid operands in comparison",
7616                                 &expression->base.source_position, orig_type_left, orig_type_right);
7617                 }
7618         } else {
7619                 semantic_comparison(&expression->binary);
7620         }
7621
7622         return expression;
7623 end_error:
7624         return create_invalid_expression();
7625 }
7626
7627 #if 0
7628 /**
7629  * Parses a __builtin_expect(, end_error) expression.
7630  */
7631 static expression_t *parse_builtin_expect(void, end_error)
7632 {
7633         expression_t *expression
7634                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
7635
7636         eat(T___builtin_expect);
7637
7638         expect('(', end_error);
7639         expression->binary.left = parse_assignment_expression();
7640         expect(',', end_error);
7641         expression->binary.right = parse_constant_expression();
7642         expect(')', end_error);
7643
7644         expression->base.type = expression->binary.left->base.type;
7645
7646         return expression;
7647 end_error:
7648         return create_invalid_expression();
7649 }
7650 #endif
7651
7652 /**
7653  * Parses a MS assume() expression.
7654  */
7655 static expression_t *parse_assume(void)
7656 {
7657         expression_t *expression = allocate_expression_zero(EXPR_UNARY_ASSUME);
7658
7659         eat(T__assume);
7660
7661         expect('(', end_error);
7662         add_anchor_token(')');
7663         expression->unary.value = parse_assignment_expression();
7664         rem_anchor_token(')');
7665         expect(')', end_error);
7666
7667         expression->base.type = type_void;
7668         return expression;
7669 end_error:
7670         return create_invalid_expression();
7671 }
7672
7673 /**
7674  * Return the declaration for a given label symbol or create a new one.
7675  *
7676  * @param symbol  the symbol of the label
7677  */
7678 static label_t *get_label(symbol_t *symbol)
7679 {
7680         entity_t *label;
7681         assert(current_function != NULL);
7682
7683         label = get_entity(symbol, NAMESPACE_LABEL);
7684         /* if we found a local label, we already created the declaration */
7685         if (label != NULL && label->kind == ENTITY_LOCAL_LABEL) {
7686                 if (label->base.parent_scope != current_scope) {
7687                         assert(label->base.parent_scope->depth < current_scope->depth);
7688                         current_function->goto_to_outer = true;
7689                 }
7690                 return &label->label;
7691         }
7692
7693         label = get_entity(symbol, NAMESPACE_LABEL);
7694         /* if we found a label in the same function, then we already created the
7695          * declaration */
7696         if (label != NULL
7697                         && label->base.parent_scope == &current_function->parameters) {
7698                 return &label->label;
7699         }
7700
7701         /* otherwise we need to create a new one */
7702         label               = allocate_entity_zero(ENTITY_LABEL);
7703         label->base.namespc = NAMESPACE_LABEL;
7704         label->base.symbol  = symbol;
7705
7706         label_push(label);
7707
7708         return &label->label;
7709 }
7710
7711 /**
7712  * Parses a GNU && label address expression.
7713  */
7714 static expression_t *parse_label_address(void)
7715 {
7716         source_position_t source_position = token.source_position;
7717         eat(T_ANDAND);
7718         if (token.type != T_IDENTIFIER) {
7719                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
7720                 goto end_error;
7721         }
7722         symbol_t *symbol = token.v.symbol;
7723         next_token();
7724
7725         label_t *label       = get_label(symbol);
7726         label->used          = true;
7727         label->address_taken = true;
7728
7729         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
7730         expression->base.source_position = source_position;
7731
7732         /* label address is threaten as a void pointer */
7733         expression->base.type           = type_void_ptr;
7734         expression->label_address.label = label;
7735         return expression;
7736 end_error:
7737         return create_invalid_expression();
7738 }
7739
7740 /**
7741  * Parse a microsoft __noop expression.
7742  */
7743 static expression_t *parse_noop_expression(void)
7744 {
7745         /* the result is a (int)0 */
7746         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
7747         cnst->base.type            = type_int;
7748         cnst->conste.v.int_value   = 0;
7749         cnst->conste.is_ms_noop    = true;
7750
7751         eat(T___noop);
7752
7753         if (token.type == '(') {
7754                 /* parse arguments */
7755                 eat('(');
7756                 add_anchor_token(')');
7757                 add_anchor_token(',');
7758
7759                 if (token.type != ')') {
7760                         while (true) {
7761                                 (void)parse_assignment_expression();
7762                                 if (token.type != ',')
7763                                         break;
7764                                 next_token();
7765                         }
7766                 }
7767         }
7768         rem_anchor_token(',');
7769         rem_anchor_token(')');
7770         expect(')', end_error);
7771
7772 end_error:
7773         return cnst;
7774 }
7775
7776 /**
7777  * Parses a primary expression.
7778  */
7779 static expression_t *parse_primary_expression(void)
7780 {
7781         switch (token.type) {
7782                 case T_false:                    return parse_bool_const(false);
7783                 case T_true:                     return parse_bool_const(true);
7784                 case T_INTEGER:                  return parse_int_const();
7785                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
7786                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
7787                 case T_FLOATINGPOINT:            return parse_float_const();
7788                 case T_STRING_LITERAL:
7789                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
7790                 case T_IDENTIFIER:               return parse_reference();
7791                 case T___FUNCTION__:
7792                 case T___func__:                 return parse_function_keyword();
7793                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
7794                 case T___FUNCSIG__:              return parse_funcsig_keyword();
7795                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
7796                 case T___builtin_offsetof:       return parse_offsetof();
7797                 case T___builtin_va_start:       return parse_va_start();
7798                 case T___builtin_va_arg:         return parse_va_arg();
7799                 case T___builtin_expect:
7800                 case T___builtin_alloca:
7801                 case T___builtin_inf:
7802                 case T___builtin_inff:
7803                 case T___builtin_infl:
7804                 case T___builtin_nan:
7805                 case T___builtin_nanf:
7806                 case T___builtin_nanl:
7807                 case T___builtin_huge_val:
7808                 case T___builtin_va_end:         return parse_builtin_symbol();
7809                 case T___builtin_isgreater:
7810                 case T___builtin_isgreaterequal:
7811                 case T___builtin_isless:
7812                 case T___builtin_islessequal:
7813                 case T___builtin_islessgreater:
7814                 case T___builtin_isunordered:    return parse_compare_builtin();
7815                 case T___builtin_constant_p:     return parse_builtin_constant();
7816                 case T___builtin_prefetch:       return parse_builtin_prefetch();
7817                 case T__assume:                  return parse_assume();
7818                 case T_ANDAND:
7819                         if (GNU_MODE)
7820                                 return parse_label_address();
7821                         break;
7822
7823                 case '(':                        return parse_parenthesized_expression();
7824                 case T___noop:                   return parse_noop_expression();
7825         }
7826
7827         errorf(HERE, "unexpected token %K, expected an expression", &token);
7828         return create_invalid_expression();
7829 }
7830
7831 /**
7832  * Check if the expression has the character type and issue a warning then.
7833  */
7834 static void check_for_char_index_type(const expression_t *expression)
7835 {
7836         type_t       *const type      = expression->base.type;
7837         const type_t *const base_type = skip_typeref(type);
7838
7839         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
7840                         warning.char_subscripts) {
7841                 warningf(&expression->base.source_position,
7842                          "array subscript has type '%T'", type);
7843         }
7844 }
7845
7846 static expression_t *parse_array_expression(expression_t *left)
7847 {
7848         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
7849
7850         eat('[');
7851         add_anchor_token(']');
7852
7853         expression_t *inside = parse_expression();
7854
7855         type_t *const orig_type_left   = left->base.type;
7856         type_t *const orig_type_inside = inside->base.type;
7857
7858         type_t *const type_left   = skip_typeref(orig_type_left);
7859         type_t *const type_inside = skip_typeref(orig_type_inside);
7860
7861         type_t                    *return_type;
7862         array_access_expression_t *array_access = &expression->array_access;
7863         if (is_type_pointer(type_left)) {
7864                 return_type             = type_left->pointer.points_to;
7865                 array_access->array_ref = left;
7866                 array_access->index     = inside;
7867                 check_for_char_index_type(inside);
7868         } else if (is_type_pointer(type_inside)) {
7869                 return_type             = type_inside->pointer.points_to;
7870                 array_access->array_ref = inside;
7871                 array_access->index     = left;
7872                 array_access->flipped   = true;
7873                 check_for_char_index_type(left);
7874         } else {
7875                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
7876                         errorf(HERE,
7877                                 "array access on object with non-pointer types '%T', '%T'",
7878                                 orig_type_left, orig_type_inside);
7879                 }
7880                 return_type             = type_error_type;
7881                 array_access->array_ref = left;
7882                 array_access->index     = inside;
7883         }
7884
7885         expression->base.type = automatic_type_conversion(return_type);
7886
7887         rem_anchor_token(']');
7888         expect(']', end_error);
7889 end_error:
7890         return expression;
7891 }
7892
7893 static expression_t *parse_typeprop(expression_kind_t const kind)
7894 {
7895         expression_t  *tp_expression = allocate_expression_zero(kind);
7896         tp_expression->base.type     = type_size_t;
7897
7898         eat(kind == EXPR_SIZEOF ? T_sizeof : T___alignof__);
7899
7900         /* we only refer to a type property, mark this case */
7901         bool old     = in_type_prop;
7902         in_type_prop = true;
7903
7904         type_t       *orig_type;
7905         expression_t *expression;
7906         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
7907                 next_token();
7908                 add_anchor_token(')');
7909                 orig_type = parse_typename();
7910                 rem_anchor_token(')');
7911                 expect(')', end_error);
7912
7913                 if (token.type == '{') {
7914                         /* It was not sizeof(type) after all.  It is sizeof of an expression
7915                          * starting with a compound literal */
7916                         expression = parse_compound_literal(orig_type);
7917                         goto typeprop_expression;
7918                 }
7919         } else {
7920                 expression = parse_sub_expression(PREC_UNARY);
7921
7922 typeprop_expression:
7923                 tp_expression->typeprop.tp_expression = expression;
7924
7925                 orig_type = revert_automatic_type_conversion(expression);
7926                 expression->base.type = orig_type;
7927         }
7928
7929         tp_expression->typeprop.type   = orig_type;
7930         type_t const* const type       = skip_typeref(orig_type);
7931         char   const* const wrong_type =
7932                 GNU_MODE && is_type_atomic(type, ATOMIC_TYPE_VOID) ? NULL                  :
7933                 is_type_incomplete(type)                           ? "incomplete"          :
7934                 type->kind == TYPE_FUNCTION                        ? "function designator" :
7935                 type->kind == TYPE_BITFIELD                        ? "bitfield"            :
7936                 NULL;
7937         if (wrong_type != NULL) {
7938                 char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7939                 errorf(&tp_expression->base.source_position,
7940                                 "operand of %s expression must not be of %s type '%T'",
7941                                 what, wrong_type, orig_type);
7942         }
7943
7944 end_error:
7945         in_type_prop = old;
7946         return tp_expression;
7947 }
7948
7949 static expression_t *parse_sizeof(void)
7950 {
7951         return parse_typeprop(EXPR_SIZEOF);
7952 }
7953
7954 static expression_t *parse_alignof(void)
7955 {
7956         return parse_typeprop(EXPR_ALIGNOF);
7957 }
7958
7959 static expression_t *parse_select_expression(expression_t *compound)
7960 {
7961         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
7962         select->select.compound = compound;
7963
7964         assert(token.type == '.' || token.type == T_MINUSGREATER);
7965         bool is_pointer = (token.type == T_MINUSGREATER);
7966         next_token();
7967
7968         if (token.type != T_IDENTIFIER) {
7969                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
7970                 return select;
7971         }
7972         symbol_t *symbol = token.v.symbol;
7973         next_token();
7974
7975         type_t *const orig_type = compound->base.type;
7976         type_t *const type      = skip_typeref(orig_type);
7977
7978         type_t *type_left;
7979         bool    saw_error = false;
7980         if (is_type_pointer(type)) {
7981                 if (!is_pointer) {
7982                         errorf(HERE,
7983                                "request for member '%Y' in something not a struct or union, but '%T'",
7984                                symbol, orig_type);
7985                         saw_error = true;
7986                 }
7987                 type_left = skip_typeref(type->pointer.points_to);
7988         } else {
7989                 if (is_pointer && is_type_valid(type)) {
7990                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7991                         saw_error = true;
7992                 }
7993                 type_left = type;
7994         }
7995
7996         entity_t *entry;
7997         if (type_left->kind == TYPE_COMPOUND_STRUCT ||
7998             type_left->kind == TYPE_COMPOUND_UNION) {
7999                 compound_t *compound = type_left->compound.compound;
8000
8001                 if (!compound->complete) {
8002                         errorf(HERE, "request for member '%Y' of incomplete type '%T'",
8003                                symbol, type_left);
8004                         goto create_error_entry;
8005                 }
8006
8007                 entry = find_compound_entry(compound, symbol);
8008                 if (entry == NULL) {
8009                         errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
8010                         goto create_error_entry;
8011                 }
8012         } else {
8013                 if (is_type_valid(type_left) && !saw_error) {
8014                         errorf(HERE,
8015                                "request for member '%Y' in something not a struct or union, but '%T'",
8016                                symbol, type_left);
8017                 }
8018 create_error_entry:
8019                 entry = create_error_entity(symbol, ENTITY_COMPOUND_MEMBER);
8020         }
8021
8022         assert(is_declaration(entry));
8023         select->select.compound_entry = entry;
8024
8025         type_t *entry_type = entry->declaration.type;
8026         type_t *res_type
8027                 = get_qualified_type(entry_type, type_left->base.qualifiers);
8028
8029         /* we always do the auto-type conversions; the & and sizeof parser contains
8030          * code to revert this! */
8031         select->base.type = automatic_type_conversion(res_type);
8032
8033         type_t *skipped = skip_typeref(res_type);
8034         if (skipped->kind == TYPE_BITFIELD) {
8035                 select->base.type = skipped->bitfield.base_type;
8036         }
8037
8038         return select;
8039 }
8040
8041 static void check_call_argument(const function_parameter_t *parameter,
8042                                 call_argument_t *argument, unsigned pos)
8043 {
8044         type_t         *expected_type      = parameter->type;
8045         type_t         *expected_type_skip = skip_typeref(expected_type);
8046         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
8047         expression_t   *arg_expr           = argument->expression;
8048         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
8049
8050         /* handle transparent union gnu extension */
8051         if (is_type_union(expected_type_skip)
8052                         && (expected_type_skip->base.modifiers
8053                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
8054                 compound_t *union_decl  = expected_type_skip->compound.compound;
8055                 type_t     *best_type   = NULL;
8056                 entity_t   *entry       = union_decl->members.entities;
8057                 for ( ; entry != NULL; entry = entry->base.next) {
8058                         assert(is_declaration(entry));
8059                         type_t *decl_type = entry->declaration.type;
8060                         error = semantic_assign(decl_type, arg_expr);
8061                         if (error == ASSIGN_ERROR_INCOMPATIBLE
8062                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
8063                                 continue;
8064
8065                         if (error == ASSIGN_SUCCESS) {
8066                                 best_type = decl_type;
8067                         } else if (best_type == NULL) {
8068                                 best_type = decl_type;
8069                         }
8070                 }
8071
8072                 if (best_type != NULL) {
8073                         expected_type = best_type;
8074                 }
8075         }
8076
8077         error                = semantic_assign(expected_type, arg_expr);
8078         argument->expression = create_implicit_cast(argument->expression,
8079                                                     expected_type);
8080
8081         if (error != ASSIGN_SUCCESS) {
8082                 /* report exact scope in error messages (like "in argument 3") */
8083                 char buf[64];
8084                 snprintf(buf, sizeof(buf), "call argument %u", pos);
8085                 report_assign_error(error, expected_type, arg_expr,     buf,
8086                                                         &arg_expr->base.source_position);
8087         } else if (warning.traditional || warning.conversion) {
8088                 type_t *const promoted_type = get_default_promoted_type(arg_type);
8089                 if (!types_compatible(expected_type_skip, promoted_type) &&
8090                     !types_compatible(expected_type_skip, type_void_ptr) &&
8091                     !types_compatible(type_void_ptr,      promoted_type)) {
8092                         /* Deliberately show the skipped types in this warning */
8093                         warningf(&arg_expr->base.source_position,
8094                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
8095                                 pos, expected_type_skip, promoted_type);
8096                 }
8097         }
8098 }
8099
8100 /**
8101  * Parse a call expression, ie. expression '( ... )'.
8102  *
8103  * @param expression  the function address
8104  */
8105 static expression_t *parse_call_expression(expression_t *expression)
8106 {
8107         expression_t      *result = allocate_expression_zero(EXPR_CALL);
8108         call_expression_t *call   = &result->call;
8109         call->function            = expression;
8110
8111         type_t *const orig_type = expression->base.type;
8112         type_t *const type      = skip_typeref(orig_type);
8113
8114         function_type_t *function_type = NULL;
8115         if (is_type_pointer(type)) {
8116                 type_t *const to_type = skip_typeref(type->pointer.points_to);
8117
8118                 if (is_type_function(to_type)) {
8119                         function_type   = &to_type->function;
8120                         call->base.type = function_type->return_type;
8121                 }
8122         }
8123
8124         if (function_type == NULL && is_type_valid(type)) {
8125                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
8126         }
8127
8128         /* parse arguments */
8129         eat('(');
8130         add_anchor_token(')');
8131         add_anchor_token(',');
8132
8133         if (token.type != ')') {
8134                 call_argument_t *last_argument = NULL;
8135
8136                 while (true) {
8137                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
8138
8139                         argument->expression = parse_assignment_expression();
8140                         if (last_argument == NULL) {
8141                                 call->arguments = argument;
8142                         } else {
8143                                 last_argument->next = argument;
8144                         }
8145                         last_argument = argument;
8146
8147                         if (token.type != ',')
8148                                 break;
8149                         next_token();
8150                 }
8151         }
8152         rem_anchor_token(',');
8153         rem_anchor_token(')');
8154         expect(')', end_error);
8155
8156         if (function_type == NULL)
8157                 return result;
8158
8159         function_parameter_t *parameter = function_type->parameters;
8160         call_argument_t      *argument  = call->arguments;
8161         if (!function_type->unspecified_parameters) {
8162                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
8163                                 parameter = parameter->next, argument = argument->next) {
8164                         check_call_argument(parameter, argument, ++pos);
8165                 }
8166
8167                 if (parameter != NULL) {
8168                         errorf(HERE, "too few arguments to function '%E'", expression);
8169                 } else if (argument != NULL && !function_type->variadic) {
8170                         errorf(HERE, "too many arguments to function '%E'", expression);
8171                 }
8172         }
8173
8174         /* do default promotion */
8175         for (; argument != NULL; argument = argument->next) {
8176                 type_t *type = argument->expression->base.type;
8177
8178                 type = get_default_promoted_type(type);
8179
8180                 argument->expression
8181                         = create_implicit_cast(argument->expression, type);
8182         }
8183
8184         check_format(&result->call);
8185
8186         if (warning.aggregate_return &&
8187             is_type_compound(skip_typeref(function_type->return_type))) {
8188                 warningf(&result->base.source_position,
8189                          "function call has aggregate value");
8190         }
8191
8192 end_error:
8193         return result;
8194 }
8195
8196 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
8197
8198 static bool same_compound_type(const type_t *type1, const type_t *type2)
8199 {
8200         return
8201                 is_type_compound(type1) &&
8202                 type1->kind == type2->kind &&
8203                 type1->compound.compound == type2->compound.compound;
8204 }
8205
8206 static expression_t const *get_reference_address(expression_t const *expr)
8207 {
8208         bool regular_take_address = true;
8209         for (;;) {
8210                 if (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8211                         expr = expr->unary.value;
8212                 } else {
8213                         regular_take_address = false;
8214                 }
8215
8216                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8217                         break;
8218
8219                 expr = expr->unary.value;
8220         }
8221
8222         if (expr->kind != EXPR_REFERENCE)
8223                 return NULL;
8224
8225         /* special case for functions which are automatically converted to a
8226          * pointer to function without an extra TAKE_ADDRESS operation */
8227         if (!regular_take_address &&
8228                         expr->reference.entity->kind != ENTITY_FUNCTION) {
8229                 return NULL;
8230         }
8231
8232         return expr;
8233 }
8234
8235 static void warn_reference_address_as_bool(expression_t const* expr)
8236 {
8237         if (!warning.address)
8238                 return;
8239
8240         expr = get_reference_address(expr);
8241         if (expr != NULL) {
8242                 warningf(&expr->base.source_position,
8243                          "the address of '%Y' will always evaluate as 'true'",
8244                          expr->reference.entity->base.symbol);
8245         }
8246 }
8247
8248 static void warn_assignment_in_condition(const expression_t *const expr)
8249 {
8250         if (!warning.parentheses)
8251                 return;
8252         if (expr->base.kind != EXPR_BINARY_ASSIGN)
8253                 return;
8254         if (expr->base.parenthesized)
8255                 return;
8256         warningf(&expr->base.source_position,
8257                         "suggest parentheses around assignment used as truth value");
8258 }
8259
8260 static void semantic_condition(expression_t const *const expr,
8261                                char const *const context)
8262 {
8263         type_t *const type = skip_typeref(expr->base.type);
8264         if (is_type_scalar(type)) {
8265                 warn_reference_address_as_bool(expr);
8266                 warn_assignment_in_condition(expr);
8267         } else if (is_type_valid(type)) {
8268                 errorf(&expr->base.source_position,
8269                                 "%s must have scalar type", context);
8270         }
8271 }
8272
8273 /**
8274  * Parse a conditional expression, ie. 'expression ? ... : ...'.
8275  *
8276  * @param expression  the conditional expression
8277  */
8278 static expression_t *parse_conditional_expression(expression_t *expression)
8279 {
8280         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
8281
8282         conditional_expression_t *conditional = &result->conditional;
8283         conditional->condition                = expression;
8284
8285         eat('?');
8286         add_anchor_token(':');
8287
8288         /* §6.5.15:2  The first operand shall have scalar type. */
8289         semantic_condition(expression, "condition of conditional operator");
8290
8291         expression_t *true_expression = expression;
8292         bool          gnu_cond = false;
8293         if (GNU_MODE && token.type == ':') {
8294                 gnu_cond = true;
8295         } else {
8296                 true_expression = parse_expression();
8297         }
8298         rem_anchor_token(':');
8299         expect(':', end_error);
8300 end_error:;
8301         expression_t *false_expression =
8302                 parse_sub_expression(c_mode & _CXX ? PREC_ASSIGNMENT : PREC_CONDITIONAL);
8303
8304         type_t *const orig_true_type  = true_expression->base.type;
8305         type_t *const orig_false_type = false_expression->base.type;
8306         type_t *const true_type       = skip_typeref(orig_true_type);
8307         type_t *const false_type      = skip_typeref(orig_false_type);
8308
8309         /* 6.5.15.3 */
8310         type_t *result_type;
8311         if (is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8312                         is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
8313                 /* ISO/IEC 14882:1998(E) §5.16:2 */
8314                 if (true_expression->kind == EXPR_UNARY_THROW) {
8315                         result_type = false_type;
8316                 } else if (false_expression->kind == EXPR_UNARY_THROW) {
8317                         result_type = true_type;
8318                 } else {
8319                         if (warning.other && (
8320                                                 !is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8321                                                 !is_type_atomic(false_type, ATOMIC_TYPE_VOID)
8322                                         )) {
8323                                 warningf(&conditional->base.source_position,
8324                                                 "ISO C forbids conditional expression with only one void side");
8325                         }
8326                         result_type = type_void;
8327                 }
8328         } else if (is_type_arithmetic(true_type)
8329                    && is_type_arithmetic(false_type)) {
8330                 result_type = semantic_arithmetic(true_type, false_type);
8331
8332                 true_expression  = create_implicit_cast(true_expression, result_type);
8333                 false_expression = create_implicit_cast(false_expression, result_type);
8334
8335                 conditional->true_expression  = true_expression;
8336                 conditional->false_expression = false_expression;
8337                 conditional->base.type        = result_type;
8338         } else if (same_compound_type(true_type, false_type)) {
8339                 /* just take 1 of the 2 types */
8340                 result_type = true_type;
8341         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
8342                 type_t *pointer_type;
8343                 type_t *other_type;
8344                 expression_t *other_expression;
8345                 if (is_type_pointer(true_type) &&
8346                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
8347                         pointer_type     = true_type;
8348                         other_type       = false_type;
8349                         other_expression = false_expression;
8350                 } else {
8351                         pointer_type     = false_type;
8352                         other_type       = true_type;
8353                         other_expression = true_expression;
8354                 }
8355
8356                 if (is_null_pointer_constant(other_expression)) {
8357                         result_type = pointer_type;
8358                 } else if (is_type_pointer(other_type)) {
8359                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
8360                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
8361
8362                         type_t *to;
8363                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
8364                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
8365                                 to = type_void;
8366                         } else if (types_compatible(get_unqualified_type(to1),
8367                                                     get_unqualified_type(to2))) {
8368                                 to = to1;
8369                         } else {
8370                                 if (warning.other) {
8371                                         warningf(&conditional->base.source_position,
8372                                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
8373                                                         true_type, false_type);
8374                                 }
8375                                 to = type_void;
8376                         }
8377
8378                         type_t *const type =
8379                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
8380                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
8381                 } else if (is_type_integer(other_type)) {
8382                         if (warning.other) {
8383                                 warningf(&conditional->base.source_position,
8384                                                 "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
8385                         }
8386                         result_type = pointer_type;
8387                 } else {
8388                         if (is_type_valid(other_type)) {
8389                                 type_error_incompatible("while parsing conditional",
8390                                                 &expression->base.source_position, true_type, false_type);
8391                         }
8392                         result_type = type_error_type;
8393                 }
8394         } else {
8395                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
8396                         type_error_incompatible("while parsing conditional",
8397                                                 &conditional->base.source_position, true_type,
8398                                                 false_type);
8399                 }
8400                 result_type = type_error_type;
8401         }
8402
8403         conditional->true_expression
8404                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
8405         conditional->false_expression
8406                 = create_implicit_cast(false_expression, result_type);
8407         conditional->base.type = result_type;
8408         return result;
8409 }
8410
8411 /**
8412  * Parse an extension expression.
8413  */
8414 static expression_t *parse_extension(void)
8415 {
8416         eat(T___extension__);
8417
8418         bool old_gcc_extension   = in_gcc_extension;
8419         in_gcc_extension         = true;
8420         expression_t *expression = parse_sub_expression(PREC_UNARY);
8421         in_gcc_extension         = old_gcc_extension;
8422         return expression;
8423 }
8424
8425 /**
8426  * Parse a __builtin_classify_type() expression.
8427  */
8428 static expression_t *parse_builtin_classify_type(void)
8429 {
8430         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
8431         result->base.type    = type_int;
8432
8433         eat(T___builtin_classify_type);
8434
8435         expect('(', end_error);
8436         add_anchor_token(')');
8437         expression_t *expression = parse_expression();
8438         rem_anchor_token(')');
8439         expect(')', end_error);
8440         result->classify_type.type_expression = expression;
8441
8442         return result;
8443 end_error:
8444         return create_invalid_expression();
8445 }
8446
8447 /**
8448  * Parse a delete expression
8449  * ISO/IEC 14882:1998(E) §5.3.5
8450  */
8451 static expression_t *parse_delete(void)
8452 {
8453         expression_t *const result = allocate_expression_zero(EXPR_UNARY_DELETE);
8454         result->base.type          = type_void;
8455
8456         eat(T_delete);
8457
8458         if (token.type == '[') {
8459                 next_token();
8460                 result->kind = EXPR_UNARY_DELETE_ARRAY;
8461                 expect(']', end_error);
8462 end_error:;
8463         }
8464
8465         expression_t *const value = parse_sub_expression(PREC_CAST);
8466         result->unary.value = value;
8467
8468         type_t *const type = skip_typeref(value->base.type);
8469         if (!is_type_pointer(type)) {
8470                 if (is_type_valid(type)) {
8471                         errorf(&value->base.source_position,
8472                                         "operand of delete must have pointer type");
8473                 }
8474         } else if (warning.other &&
8475                         is_type_atomic(skip_typeref(type->pointer.points_to), ATOMIC_TYPE_VOID)) {
8476                 warningf(&value->base.source_position,
8477                                 "deleting 'void*' is undefined");
8478         }
8479
8480         return result;
8481 }
8482
8483 /**
8484  * Parse a throw expression
8485  * ISO/IEC 14882:1998(E) §15:1
8486  */
8487 static expression_t *parse_throw(void)
8488 {
8489         expression_t *const result = allocate_expression_zero(EXPR_UNARY_THROW);
8490         result->base.type          = type_void;
8491
8492         eat(T_throw);
8493
8494         expression_t *value = NULL;
8495         switch (token.type) {
8496                 EXPRESSION_START {
8497                         value = parse_assignment_expression();
8498                         /* ISO/IEC 14882:1998(E) §15.1:3 */
8499                         type_t *const orig_type = value->base.type;
8500                         type_t *const type      = skip_typeref(orig_type);
8501                         if (is_type_incomplete(type)) {
8502                                 errorf(&value->base.source_position,
8503                                                 "cannot throw object of incomplete type '%T'", orig_type);
8504                         } else if (is_type_pointer(type)) {
8505                                 type_t *const points_to = skip_typeref(type->pointer.points_to);
8506                                 if (is_type_incomplete(points_to) &&
8507                                                 !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8508                                         errorf(&value->base.source_position,
8509                                                         "cannot throw pointer to incomplete type '%T'", orig_type);
8510                                 }
8511                         }
8512                 }
8513
8514                 default:
8515                         break;
8516         }
8517         result->unary.value = value;
8518
8519         return result;
8520 }
8521
8522 static bool check_pointer_arithmetic(const source_position_t *source_position,
8523                                      type_t *pointer_type,
8524                                      type_t *orig_pointer_type)
8525 {
8526         type_t *points_to = pointer_type->pointer.points_to;
8527         points_to = skip_typeref(points_to);
8528
8529         if (is_type_incomplete(points_to)) {
8530                 if (!GNU_MODE || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8531                         errorf(source_position,
8532                                "arithmetic with pointer to incomplete type '%T' not allowed",
8533                                orig_pointer_type);
8534                         return false;
8535                 } else if (warning.pointer_arith) {
8536                         warningf(source_position,
8537                                  "pointer of type '%T' used in arithmetic",
8538                                  orig_pointer_type);
8539                 }
8540         } else if (is_type_function(points_to)) {
8541                 if (!GNU_MODE) {
8542                         errorf(source_position,
8543                                "arithmetic with pointer to function type '%T' not allowed",
8544                                orig_pointer_type);
8545                         return false;
8546                 } else if (warning.pointer_arith) {
8547                         warningf(source_position,
8548                                  "pointer to a function '%T' used in arithmetic",
8549                                  orig_pointer_type);
8550                 }
8551         }
8552         return true;
8553 }
8554
8555 static bool is_lvalue(const expression_t *expression)
8556 {
8557         /* TODO: doesn't seem to be consistent with §6.3.2.1:1 */
8558         switch (expression->kind) {
8559         case EXPR_ARRAY_ACCESS:
8560         case EXPR_COMPOUND_LITERAL:
8561         case EXPR_REFERENCE:
8562         case EXPR_SELECT:
8563         case EXPR_UNARY_DEREFERENCE:
8564                 return true;
8565
8566         default: {
8567           type_t *type = skip_typeref(expression->base.type);
8568           return
8569                 /* ISO/IEC 14882:1998(E) §3.10:3 */
8570                 is_type_reference(type) ||
8571                 /* Claim it is an lvalue, if the type is invalid.  There was a parse
8572                  * error before, which maybe prevented properly recognizing it as
8573                  * lvalue. */
8574                 !is_type_valid(type);
8575         }
8576         }
8577 }
8578
8579 static void semantic_incdec(unary_expression_t *expression)
8580 {
8581         type_t *const orig_type = expression->value->base.type;
8582         type_t *const type      = skip_typeref(orig_type);
8583         if (is_type_pointer(type)) {
8584                 if (!check_pointer_arithmetic(&expression->base.source_position,
8585                                               type, orig_type)) {
8586                         return;
8587                 }
8588         } else if (!is_type_real(type) && is_type_valid(type)) {
8589                 /* TODO: improve error message */
8590                 errorf(&expression->base.source_position,
8591                        "operation needs an arithmetic or pointer type");
8592                 return;
8593         }
8594         if (!is_lvalue(expression->value)) {
8595                 /* TODO: improve error message */
8596                 errorf(&expression->base.source_position, "lvalue required as operand");
8597         }
8598         expression->base.type = orig_type;
8599 }
8600
8601 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
8602 {
8603         type_t *const orig_type = expression->value->base.type;
8604         type_t *const type      = skip_typeref(orig_type);
8605         if (!is_type_arithmetic(type)) {
8606                 if (is_type_valid(type)) {
8607                         /* TODO: improve error message */
8608                         errorf(&expression->base.source_position,
8609                                 "operation needs an arithmetic type");
8610                 }
8611                 return;
8612         }
8613
8614         expression->base.type = orig_type;
8615 }
8616
8617 static void semantic_unexpr_plus(unary_expression_t *expression)
8618 {
8619         semantic_unexpr_arithmetic(expression);
8620         if (warning.traditional)
8621                 warningf(&expression->base.source_position,
8622                         "traditional C rejects the unary plus operator");
8623 }
8624
8625 static void semantic_not(unary_expression_t *expression)
8626 {
8627         /* §6.5.3.3:1  The operand [...] of the ! operator, scalar type. */
8628         semantic_condition(expression->value, "operand of !");
8629         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8630 }
8631
8632 static void semantic_unexpr_integer(unary_expression_t *expression)
8633 {
8634         type_t *const orig_type = expression->value->base.type;
8635         type_t *const type      = skip_typeref(orig_type);
8636         if (!is_type_integer(type)) {
8637                 if (is_type_valid(type)) {
8638                         errorf(&expression->base.source_position,
8639                                "operand of ~ must be of integer type");
8640                 }
8641                 return;
8642         }
8643
8644         expression->base.type = orig_type;
8645 }
8646
8647 static void semantic_dereference(unary_expression_t *expression)
8648 {
8649         type_t *const orig_type = expression->value->base.type;
8650         type_t *const type      = skip_typeref(orig_type);
8651         if (!is_type_pointer(type)) {
8652                 if (is_type_valid(type)) {
8653                         errorf(&expression->base.source_position,
8654                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
8655                 }
8656                 return;
8657         }
8658
8659         type_t *result_type   = type->pointer.points_to;
8660         result_type           = automatic_type_conversion(result_type);
8661         expression->base.type = result_type;
8662 }
8663
8664 /**
8665  * Record that an address is taken (expression represents an lvalue).
8666  *
8667  * @param expression       the expression
8668  * @param may_be_register  if true, the expression might be an register
8669  */
8670 static void set_address_taken(expression_t *expression, bool may_be_register)
8671 {
8672         if (expression->kind != EXPR_REFERENCE)
8673                 return;
8674
8675         entity_t *const entity = expression->reference.entity;
8676
8677         if (entity->kind != ENTITY_VARIABLE && entity->kind != ENTITY_PARAMETER)
8678                 return;
8679
8680         if (entity->declaration.storage_class == STORAGE_CLASS_REGISTER
8681                         && !may_be_register) {
8682                 errorf(&expression->base.source_position,
8683                                 "address of register %s '%Y' requested",
8684                                 get_entity_kind_name(entity->kind),     entity->base.symbol);
8685         }
8686
8687         if (entity->kind == ENTITY_VARIABLE) {
8688                 entity->variable.address_taken = true;
8689         } else {
8690                 assert(entity->kind == ENTITY_PARAMETER);
8691                 entity->parameter.address_taken = true;
8692         }
8693 }
8694
8695 /**
8696  * Check the semantic of the address taken expression.
8697  */
8698 static void semantic_take_addr(unary_expression_t *expression)
8699 {
8700         expression_t *value = expression->value;
8701         value->base.type    = revert_automatic_type_conversion(value);
8702
8703         type_t *orig_type = value->base.type;
8704         type_t *type      = skip_typeref(orig_type);
8705         if (!is_type_valid(type))
8706                 return;
8707
8708         /* §6.5.3.2 */
8709         if (!is_lvalue(value)) {
8710                 errorf(&expression->base.source_position, "'&' requires an lvalue");
8711         }
8712         if (type->kind == TYPE_BITFIELD) {
8713                 errorf(&expression->base.source_position,
8714                        "'&' not allowed on object with bitfield type '%T'",
8715                        type);
8716         }
8717
8718         set_address_taken(value, false);
8719
8720         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
8721 }
8722
8723 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc) \
8724 static expression_t *parse_##unexpression_type(void)                         \
8725 {                                                                            \
8726         expression_t *unary_expression                                           \
8727                 = allocate_expression_zero(unexpression_type);                       \
8728         eat(token_type);                                                         \
8729         unary_expression->unary.value = parse_sub_expression(PREC_UNARY);        \
8730                                                                                  \
8731         sfunc(&unary_expression->unary);                                         \
8732                                                                                  \
8733         return unary_expression;                                                 \
8734 }
8735
8736 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
8737                                semantic_unexpr_arithmetic)
8738 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
8739                                semantic_unexpr_plus)
8740 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
8741                                semantic_not)
8742 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
8743                                semantic_dereference)
8744 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
8745                                semantic_take_addr)
8746 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
8747                                semantic_unexpr_integer)
8748 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
8749                                semantic_incdec)
8750 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
8751                                semantic_incdec)
8752
8753 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
8754                                                sfunc)                         \
8755 static expression_t *parse_##unexpression_type(expression_t *left)            \
8756 {                                                                             \
8757         expression_t *unary_expression                                            \
8758                 = allocate_expression_zero(unexpression_type);                        \
8759         eat(token_type);                                                          \
8760         unary_expression->unary.value = left;                                     \
8761                                                                                   \
8762         sfunc(&unary_expression->unary);                                          \
8763                                                                               \
8764         return unary_expression;                                                  \
8765 }
8766
8767 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
8768                                        EXPR_UNARY_POSTFIX_INCREMENT,
8769                                        semantic_incdec)
8770 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
8771                                        EXPR_UNARY_POSTFIX_DECREMENT,
8772                                        semantic_incdec)
8773
8774 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
8775 {
8776         /* TODO: handle complex + imaginary types */
8777
8778         type_left  = get_unqualified_type(type_left);
8779         type_right = get_unqualified_type(type_right);
8780
8781         /* § 6.3.1.8 Usual arithmetic conversions */
8782         if (type_left == type_long_double || type_right == type_long_double) {
8783                 return type_long_double;
8784         } else if (type_left == type_double || type_right == type_double) {
8785                 return type_double;
8786         } else if (type_left == type_float || type_right == type_float) {
8787                 return type_float;
8788         }
8789
8790         type_left  = promote_integer(type_left);
8791         type_right = promote_integer(type_right);
8792
8793         if (type_left == type_right)
8794                 return type_left;
8795
8796         bool const signed_left  = is_type_signed(type_left);
8797         bool const signed_right = is_type_signed(type_right);
8798         int const  rank_left    = get_rank(type_left);
8799         int const  rank_right   = get_rank(type_right);
8800
8801         if (signed_left == signed_right)
8802                 return rank_left >= rank_right ? type_left : type_right;
8803
8804         int     s_rank;
8805         int     u_rank;
8806         type_t *s_type;
8807         type_t *u_type;
8808         if (signed_left) {
8809                 s_rank = rank_left;
8810                 s_type = type_left;
8811                 u_rank = rank_right;
8812                 u_type = type_right;
8813         } else {
8814                 s_rank = rank_right;
8815                 s_type = type_right;
8816                 u_rank = rank_left;
8817                 u_type = type_left;
8818         }
8819
8820         if (u_rank >= s_rank)
8821                 return u_type;
8822
8823         /* casting rank to atomic_type_kind is a bit hacky, but makes things
8824          * easier here... */
8825         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
8826                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
8827                 return s_type;
8828
8829         switch (s_rank) {
8830                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
8831                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
8832                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
8833
8834                 default: panic("invalid atomic type");
8835         }
8836 }
8837
8838 /**
8839  * Check the semantic restrictions for a binary expression.
8840  */
8841 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
8842 {
8843         expression_t *const left            = expression->left;
8844         expression_t *const right           = expression->right;
8845         type_t       *const orig_type_left  = left->base.type;
8846         type_t       *const orig_type_right = right->base.type;
8847         type_t       *const type_left       = skip_typeref(orig_type_left);
8848         type_t       *const type_right      = skip_typeref(orig_type_right);
8849
8850         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8851                 /* TODO: improve error message */
8852                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8853                         errorf(&expression->base.source_position,
8854                                "operation needs arithmetic types");
8855                 }
8856                 return;
8857         }
8858
8859         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8860         expression->left      = create_implicit_cast(left, arithmetic_type);
8861         expression->right     = create_implicit_cast(right, arithmetic_type);
8862         expression->base.type = arithmetic_type;
8863 }
8864
8865 static void warn_div_by_zero(binary_expression_t const *const expression)
8866 {
8867         if (!warning.div_by_zero ||
8868             !is_type_integer(expression->base.type))
8869                 return;
8870
8871         expression_t const *const right = expression->right;
8872         /* The type of the right operand can be different for /= */
8873         if (is_type_integer(right->base.type) &&
8874             is_constant_expression(right)     &&
8875             fold_constant(right) == 0) {
8876                 warningf(&expression->base.source_position, "division by zero");
8877         }
8878 }
8879
8880 /**
8881  * Check the semantic restrictions for a div/mod expression.
8882  */
8883 static void semantic_divmod_arithmetic(binary_expression_t *expression) {
8884         semantic_binexpr_arithmetic(expression);
8885         warn_div_by_zero(expression);
8886 }
8887
8888 static void warn_addsub_in_shift(const expression_t *const expr)
8889 {
8890         if (expr->base.parenthesized)
8891                 return;
8892
8893         char op;
8894         switch (expr->kind) {
8895                 case EXPR_BINARY_ADD: op = '+'; break;
8896                 case EXPR_BINARY_SUB: op = '-'; break;
8897                 default:              return;
8898         }
8899
8900         warningf(&expr->base.source_position,
8901                         "suggest parentheses around '%c' inside shift", op);
8902 }
8903
8904 static void semantic_shift_op(binary_expression_t *expression)
8905 {
8906         expression_t *const left            = expression->left;
8907         expression_t *const right           = expression->right;
8908         type_t       *const orig_type_left  = left->base.type;
8909         type_t       *const orig_type_right = right->base.type;
8910         type_t       *      type_left       = skip_typeref(orig_type_left);
8911         type_t       *      type_right      = skip_typeref(orig_type_right);
8912
8913         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8914                 /* TODO: improve error message */
8915                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8916                         errorf(&expression->base.source_position,
8917                                "operands of shift operation must have integer types");
8918                 }
8919                 return;
8920         }
8921
8922         if (warning.parentheses) {
8923                 warn_addsub_in_shift(left);
8924                 warn_addsub_in_shift(right);
8925         }
8926
8927         type_left  = promote_integer(type_left);
8928         type_right = promote_integer(type_right);
8929
8930         expression->left      = create_implicit_cast(left, type_left);
8931         expression->right     = create_implicit_cast(right, type_right);
8932         expression->base.type = type_left;
8933 }
8934
8935 static void semantic_add(binary_expression_t *expression)
8936 {
8937         expression_t *const left            = expression->left;
8938         expression_t *const right           = expression->right;
8939         type_t       *const orig_type_left  = left->base.type;
8940         type_t       *const orig_type_right = right->base.type;
8941         type_t       *const type_left       = skip_typeref(orig_type_left);
8942         type_t       *const type_right      = skip_typeref(orig_type_right);
8943
8944         /* § 6.5.6 */
8945         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8946                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8947                 expression->left  = create_implicit_cast(left, arithmetic_type);
8948                 expression->right = create_implicit_cast(right, arithmetic_type);
8949                 expression->base.type = arithmetic_type;
8950         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8951                 check_pointer_arithmetic(&expression->base.source_position,
8952                                          type_left, orig_type_left);
8953                 expression->base.type = type_left;
8954         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
8955                 check_pointer_arithmetic(&expression->base.source_position,
8956                                          type_right, orig_type_right);
8957                 expression->base.type = type_right;
8958         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8959                 errorf(&expression->base.source_position,
8960                        "invalid operands to binary + ('%T', '%T')",
8961                        orig_type_left, orig_type_right);
8962         }
8963 }
8964
8965 static void semantic_sub(binary_expression_t *expression)
8966 {
8967         expression_t            *const left            = expression->left;
8968         expression_t            *const right           = expression->right;
8969         type_t                  *const orig_type_left  = left->base.type;
8970         type_t                  *const orig_type_right = right->base.type;
8971         type_t                  *const type_left       = skip_typeref(orig_type_left);
8972         type_t                  *const type_right      = skip_typeref(orig_type_right);
8973         source_position_t const *const pos             = &expression->base.source_position;
8974
8975         /* § 5.6.5 */
8976         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8977                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8978                 expression->left        = create_implicit_cast(left, arithmetic_type);
8979                 expression->right       = create_implicit_cast(right, arithmetic_type);
8980                 expression->base.type =  arithmetic_type;
8981         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8982                 check_pointer_arithmetic(&expression->base.source_position,
8983                                          type_left, orig_type_left);
8984                 expression->base.type = type_left;
8985         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8986                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
8987                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
8988                 if (!types_compatible(unqual_left, unqual_right)) {
8989                         errorf(pos,
8990                                "subtracting pointers to incompatible types '%T' and '%T'",
8991                                orig_type_left, orig_type_right);
8992                 } else if (!is_type_object(unqual_left)) {
8993                         if (!is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
8994                                 errorf(pos, "subtracting pointers to non-object types '%T'",
8995                                        orig_type_left);
8996                         } else if (warning.other) {
8997                                 warningf(pos, "subtracting pointers to void");
8998                         }
8999                 }
9000                 expression->base.type = type_ptrdiff_t;
9001         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9002                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
9003                        orig_type_left, orig_type_right);
9004         }
9005 }
9006
9007 static void warn_string_literal_address(expression_t const* expr)
9008 {
9009         while (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
9010                 expr = expr->unary.value;
9011                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
9012                         return;
9013                 expr = expr->unary.value;
9014         }
9015
9016         if (expr->kind == EXPR_STRING_LITERAL ||
9017             expr->kind == EXPR_WIDE_STRING_LITERAL) {
9018                 warningf(&expr->base.source_position,
9019                         "comparison with string literal results in unspecified behaviour");
9020         }
9021 }
9022
9023 static void warn_comparison_in_comparison(const expression_t *const expr)
9024 {
9025         if (expr->base.parenthesized)
9026                 return;
9027         switch (expr->base.kind) {
9028                 case EXPR_BINARY_LESS:
9029                 case EXPR_BINARY_GREATER:
9030                 case EXPR_BINARY_LESSEQUAL:
9031                 case EXPR_BINARY_GREATEREQUAL:
9032                 case EXPR_BINARY_NOTEQUAL:
9033                 case EXPR_BINARY_EQUAL:
9034                         warningf(&expr->base.source_position,
9035                                         "comparisons like 'x <= y < z' do not have their mathematical meaning");
9036                         break;
9037                 default:
9038                         break;
9039         }
9040 }
9041
9042 static bool maybe_negative(expression_t const *const expr)
9043 {
9044         return
9045                 !is_constant_expression(expr) ||
9046                 fold_constant(expr) < 0;
9047 }
9048
9049 /**
9050  * Check the semantics of comparison expressions.
9051  *
9052  * @param expression   The expression to check.
9053  */
9054 static void semantic_comparison(binary_expression_t *expression)
9055 {
9056         expression_t *left  = expression->left;
9057         expression_t *right = expression->right;
9058
9059         if (warning.address) {
9060                 warn_string_literal_address(left);
9061                 warn_string_literal_address(right);
9062
9063                 expression_t const* const func_left = get_reference_address(left);
9064                 if (func_left != NULL && is_null_pointer_constant(right)) {
9065                         warningf(&expression->base.source_position,
9066                                  "the address of '%Y' will never be NULL",
9067                                  func_left->reference.entity->base.symbol);
9068                 }
9069
9070                 expression_t const* const func_right = get_reference_address(right);
9071                 if (func_right != NULL && is_null_pointer_constant(right)) {
9072                         warningf(&expression->base.source_position,
9073                                  "the address of '%Y' will never be NULL",
9074                                  func_right->reference.entity->base.symbol);
9075                 }
9076         }
9077
9078         if (warning.parentheses) {
9079                 warn_comparison_in_comparison(left);
9080                 warn_comparison_in_comparison(right);
9081         }
9082
9083         type_t *orig_type_left  = left->base.type;
9084         type_t *orig_type_right = right->base.type;
9085         type_t *type_left       = skip_typeref(orig_type_left);
9086         type_t *type_right      = skip_typeref(orig_type_right);
9087
9088         /* TODO non-arithmetic types */
9089         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
9090                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
9091
9092                 /* test for signed vs unsigned compares */
9093                 if (warning.sign_compare && is_type_integer(arithmetic_type)) {
9094                         bool const signed_left  = is_type_signed(type_left);
9095                         bool const signed_right = is_type_signed(type_right);
9096                         if (signed_left != signed_right) {
9097                                 /* FIXME long long needs better const folding magic */
9098                                 /* TODO check whether constant value can be represented by other type */
9099                                 if ((signed_left  && maybe_negative(left)) ||
9100                                                 (signed_right && maybe_negative(right))) {
9101                                         warningf(&expression->base.source_position,
9102                                                         "comparison between signed and unsigned");
9103                                 }
9104                         }
9105                 }
9106
9107                 expression->left        = create_implicit_cast(left, arithmetic_type);
9108                 expression->right       = create_implicit_cast(right, arithmetic_type);
9109                 expression->base.type   = arithmetic_type;
9110                 if (warning.float_equal &&
9111                     (expression->base.kind == EXPR_BINARY_EQUAL ||
9112                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
9113                     is_type_float(arithmetic_type)) {
9114                         warningf(&expression->base.source_position,
9115                                  "comparing floating point with == or != is unsafe");
9116                 }
9117         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
9118                 /* TODO check compatibility */
9119         } else if (is_type_pointer(type_left)) {
9120                 expression->right = create_implicit_cast(right, type_left);
9121         } else if (is_type_pointer(type_right)) {
9122                 expression->left = create_implicit_cast(left, type_right);
9123         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9124                 type_error_incompatible("invalid operands in comparison",
9125                                         &expression->base.source_position,
9126                                         type_left, type_right);
9127         }
9128         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9129 }
9130
9131 /**
9132  * Checks if a compound type has constant fields.
9133  */
9134 static bool has_const_fields(const compound_type_t *type)
9135 {
9136         compound_t *compound = type->compound;
9137         entity_t   *entry    = compound->members.entities;
9138
9139         for (; entry != NULL; entry = entry->base.next) {
9140                 if (!is_declaration(entry))
9141                         continue;
9142
9143                 const type_t *decl_type = skip_typeref(entry->declaration.type);
9144                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
9145                         return true;
9146         }
9147
9148         return false;
9149 }
9150
9151 static bool is_valid_assignment_lhs(expression_t const* const left)
9152 {
9153         type_t *const orig_type_left = revert_automatic_type_conversion(left);
9154         type_t *const type_left      = skip_typeref(orig_type_left);
9155
9156         if (!is_lvalue(left)) {
9157                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
9158                        left);
9159                 return false;
9160         }
9161
9162         if (left->kind == EXPR_REFERENCE
9163                         && left->reference.entity->kind == ENTITY_FUNCTION) {
9164                 errorf(HERE, "cannot assign to function '%E'", left);
9165                 return false;
9166         }
9167
9168         if (is_type_array(type_left)) {
9169                 errorf(HERE, "cannot assign to array '%E'", left);
9170                 return false;
9171         }
9172         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
9173                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
9174                        orig_type_left);
9175                 return false;
9176         }
9177         if (is_type_incomplete(type_left)) {
9178                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
9179                        left, orig_type_left);
9180                 return false;
9181         }
9182         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
9183                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
9184                        left, orig_type_left);
9185                 return false;
9186         }
9187
9188         return true;
9189 }
9190
9191 static void semantic_arithmetic_assign(binary_expression_t *expression)
9192 {
9193         expression_t *left            = expression->left;
9194         expression_t *right           = expression->right;
9195         type_t       *orig_type_left  = left->base.type;
9196         type_t       *orig_type_right = right->base.type;
9197
9198         if (!is_valid_assignment_lhs(left))
9199                 return;
9200
9201         type_t *type_left  = skip_typeref(orig_type_left);
9202         type_t *type_right = skip_typeref(orig_type_right);
9203
9204         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
9205                 /* TODO: improve error message */
9206                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
9207                         errorf(&expression->base.source_position,
9208                                "operation needs arithmetic types");
9209                 }
9210                 return;
9211         }
9212
9213         /* combined instructions are tricky. We can't create an implicit cast on
9214          * the left side, because we need the uncasted form for the store.
9215          * The ast2firm pass has to know that left_type must be right_type
9216          * for the arithmetic operation and create a cast by itself */
9217         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
9218         expression->right       = create_implicit_cast(right, arithmetic_type);
9219         expression->base.type   = type_left;
9220 }
9221
9222 static void semantic_divmod_assign(binary_expression_t *expression)
9223 {
9224         semantic_arithmetic_assign(expression);
9225         warn_div_by_zero(expression);
9226 }
9227
9228 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
9229 {
9230         expression_t *const left            = expression->left;
9231         expression_t *const right           = expression->right;
9232         type_t       *const orig_type_left  = left->base.type;
9233         type_t       *const orig_type_right = right->base.type;
9234         type_t       *const type_left       = skip_typeref(orig_type_left);
9235         type_t       *const type_right      = skip_typeref(orig_type_right);
9236
9237         if (!is_valid_assignment_lhs(left))
9238                 return;
9239
9240         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
9241                 /* combined instructions are tricky. We can't create an implicit cast on
9242                  * the left side, because we need the uncasted form for the store.
9243                  * The ast2firm pass has to know that left_type must be right_type
9244                  * for the arithmetic operation and create a cast by itself */
9245                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
9246                 expression->right     = create_implicit_cast(right, arithmetic_type);
9247                 expression->base.type = type_left;
9248         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
9249                 check_pointer_arithmetic(&expression->base.source_position,
9250                                          type_left, orig_type_left);
9251                 expression->base.type = type_left;
9252         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9253                 errorf(&expression->base.source_position,
9254                        "incompatible types '%T' and '%T' in assignment",
9255                        orig_type_left, orig_type_right);
9256         }
9257 }
9258
9259 static void warn_logical_and_within_or(const expression_t *const expr)
9260 {
9261         if (expr->base.kind != EXPR_BINARY_LOGICAL_AND)
9262                 return;
9263         if (expr->base.parenthesized)
9264                 return;
9265         warningf(&expr->base.source_position,
9266                         "suggest parentheses around && within ||");
9267 }
9268
9269 /**
9270  * Check the semantic restrictions of a logical expression.
9271  */
9272 static void semantic_logical_op(binary_expression_t *expression)
9273 {
9274         /* §6.5.13:2  Each of the operands shall have scalar type.
9275          * §6.5.14:2  Each of the operands shall have scalar type. */
9276         semantic_condition(expression->left,   "left operand of logical operator");
9277         semantic_condition(expression->right, "right operand of logical operator");
9278         if (expression->base.kind == EXPR_BINARY_LOGICAL_OR &&
9279                         warning.parentheses) {
9280                 warn_logical_and_within_or(expression->left);
9281                 warn_logical_and_within_or(expression->right);
9282         }
9283         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9284 }
9285
9286 /**
9287  * Check the semantic restrictions of a binary assign expression.
9288  */
9289 static void semantic_binexpr_assign(binary_expression_t *expression)
9290 {
9291         expression_t *left           = expression->left;
9292         type_t       *orig_type_left = left->base.type;
9293
9294         if (!is_valid_assignment_lhs(left))
9295                 return;
9296
9297         assign_error_t error = semantic_assign(orig_type_left, expression->right);
9298         report_assign_error(error, orig_type_left, expression->right,
9299                         "assignment", &left->base.source_position);
9300         expression->right = create_implicit_cast(expression->right, orig_type_left);
9301         expression->base.type = orig_type_left;
9302 }
9303
9304 /**
9305  * Determine if the outermost operation (or parts thereof) of the given
9306  * expression has no effect in order to generate a warning about this fact.
9307  * Therefore in some cases this only examines some of the operands of the
9308  * expression (see comments in the function and examples below).
9309  * Examples:
9310  *   f() + 23;    // warning, because + has no effect
9311  *   x || f();    // no warning, because x controls execution of f()
9312  *   x ? y : f(); // warning, because y has no effect
9313  *   (void)x;     // no warning to be able to suppress the warning
9314  * This function can NOT be used for an "expression has definitely no effect"-
9315  * analysis. */
9316 static bool expression_has_effect(const expression_t *const expr)
9317 {
9318         switch (expr->kind) {
9319                 case EXPR_UNKNOWN:                   break;
9320                 case EXPR_INVALID:                   return true; /* do NOT warn */
9321                 case EXPR_REFERENCE:                 return false;
9322                 case EXPR_REFERENCE_ENUM_VALUE:      return false;
9323                 /* suppress the warning for microsoft __noop operations */
9324                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
9325                 case EXPR_CHARACTER_CONSTANT:        return false;
9326                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
9327                 case EXPR_STRING_LITERAL:            return false;
9328                 case EXPR_WIDE_STRING_LITERAL:       return false;
9329                 case EXPR_LABEL_ADDRESS:             return false;
9330
9331                 case EXPR_CALL: {
9332                         const call_expression_t *const call = &expr->call;
9333                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
9334                                 return true;
9335
9336                         switch (call->function->builtin_symbol.symbol->ID) {
9337                                 case T___builtin_va_end: return true;
9338                                 default:                 return false;
9339                         }
9340                 }
9341
9342                 /* Generate the warning if either the left or right hand side of a
9343                  * conditional expression has no effect */
9344                 case EXPR_CONDITIONAL: {
9345                         const conditional_expression_t *const cond = &expr->conditional;
9346                         return
9347                                 expression_has_effect(cond->true_expression) &&
9348                                 expression_has_effect(cond->false_expression);
9349                 }
9350
9351                 case EXPR_SELECT:                    return false;
9352                 case EXPR_ARRAY_ACCESS:              return false;
9353                 case EXPR_SIZEOF:                    return false;
9354                 case EXPR_CLASSIFY_TYPE:             return false;
9355                 case EXPR_ALIGNOF:                   return false;
9356
9357                 case EXPR_FUNCNAME:                  return false;
9358                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
9359                 case EXPR_BUILTIN_CONSTANT_P:        return false;
9360                 case EXPR_BUILTIN_PREFETCH:          return true;
9361                 case EXPR_OFFSETOF:                  return false;
9362                 case EXPR_VA_START:                  return true;
9363                 case EXPR_VA_ARG:                    return true;
9364                 case EXPR_STATEMENT:                 return true; // TODO
9365                 case EXPR_COMPOUND_LITERAL:          return false;
9366
9367                 case EXPR_UNARY_NEGATE:              return false;
9368                 case EXPR_UNARY_PLUS:                return false;
9369                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
9370                 case EXPR_UNARY_NOT:                 return false;
9371                 case EXPR_UNARY_DEREFERENCE:         return false;
9372                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
9373                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
9374                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
9375                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
9376                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
9377
9378                 /* Treat void casts as if they have an effect in order to being able to
9379                  * suppress the warning */
9380                 case EXPR_UNARY_CAST: {
9381                         type_t *const type = skip_typeref(expr->base.type);
9382                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
9383                 }
9384
9385                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
9386                 case EXPR_UNARY_ASSUME:              return true;
9387                 case EXPR_UNARY_DELETE:              return true;
9388                 case EXPR_UNARY_DELETE_ARRAY:        return true;
9389                 case EXPR_UNARY_THROW:               return true;
9390
9391                 case EXPR_BINARY_ADD:                return false;
9392                 case EXPR_BINARY_SUB:                return false;
9393                 case EXPR_BINARY_MUL:                return false;
9394                 case EXPR_BINARY_DIV:                return false;
9395                 case EXPR_BINARY_MOD:                return false;
9396                 case EXPR_BINARY_EQUAL:              return false;
9397                 case EXPR_BINARY_NOTEQUAL:           return false;
9398                 case EXPR_BINARY_LESS:               return false;
9399                 case EXPR_BINARY_LESSEQUAL:          return false;
9400                 case EXPR_BINARY_GREATER:            return false;
9401                 case EXPR_BINARY_GREATEREQUAL:       return false;
9402                 case EXPR_BINARY_BITWISE_AND:        return false;
9403                 case EXPR_BINARY_BITWISE_OR:         return false;
9404                 case EXPR_BINARY_BITWISE_XOR:        return false;
9405                 case EXPR_BINARY_SHIFTLEFT:          return false;
9406                 case EXPR_BINARY_SHIFTRIGHT:         return false;
9407                 case EXPR_BINARY_ASSIGN:             return true;
9408                 case EXPR_BINARY_MUL_ASSIGN:         return true;
9409                 case EXPR_BINARY_DIV_ASSIGN:         return true;
9410                 case EXPR_BINARY_MOD_ASSIGN:         return true;
9411                 case EXPR_BINARY_ADD_ASSIGN:         return true;
9412                 case EXPR_BINARY_SUB_ASSIGN:         return true;
9413                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
9414                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
9415                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
9416                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
9417                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
9418
9419                 /* Only examine the right hand side of && and ||, because the left hand
9420                  * side already has the effect of controlling the execution of the right
9421                  * hand side */
9422                 case EXPR_BINARY_LOGICAL_AND:
9423                 case EXPR_BINARY_LOGICAL_OR:
9424                 /* Only examine the right hand side of a comma expression, because the left
9425                  * hand side has a separate warning */
9426                 case EXPR_BINARY_COMMA:
9427                         return expression_has_effect(expr->binary.right);
9428
9429                 case EXPR_BINARY_ISGREATER:          return false;
9430                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
9431                 case EXPR_BINARY_ISLESS:             return false;
9432                 case EXPR_BINARY_ISLESSEQUAL:        return false;
9433                 case EXPR_BINARY_ISLESSGREATER:      return false;
9434                 case EXPR_BINARY_ISUNORDERED:        return false;
9435         }
9436
9437         internal_errorf(HERE, "unexpected expression");
9438 }
9439
9440 static void semantic_comma(binary_expression_t *expression)
9441 {
9442         if (warning.unused_value) {
9443                 const expression_t *const left = expression->left;
9444                 if (!expression_has_effect(left)) {
9445                         warningf(&left->base.source_position,
9446                                  "left-hand operand of comma expression has no effect");
9447                 }
9448         }
9449         expression->base.type = expression->right->base.type;
9450 }
9451
9452 /**
9453  * @param prec_r precedence of the right operand
9454  */
9455 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, prec_r, sfunc) \
9456 static expression_t *parse_##binexpression_type(expression_t *left)          \
9457 {                                                                            \
9458         expression_t *binexpr = allocate_expression_zero(binexpression_type);    \
9459         binexpr->binary.left  = left;                                            \
9460         eat(token_type);                                                         \
9461                                                                              \
9462         expression_t *right = parse_sub_expression(prec_r);                      \
9463                                                                              \
9464         binexpr->binary.right = right;                                           \
9465         sfunc(&binexpr->binary);                                                 \
9466                                                                              \
9467         return binexpr;                                                          \
9468 }
9469
9470 CREATE_BINEXPR_PARSER('*',                    EXPR_BINARY_MUL,                PREC_CAST,           semantic_binexpr_arithmetic)
9471 CREATE_BINEXPR_PARSER('/',                    EXPR_BINARY_DIV,                PREC_CAST,           semantic_divmod_arithmetic)
9472 CREATE_BINEXPR_PARSER('%',                    EXPR_BINARY_MOD,                PREC_CAST,           semantic_divmod_arithmetic)
9473 CREATE_BINEXPR_PARSER('+',                    EXPR_BINARY_ADD,                PREC_MULTIPLICATIVE, semantic_add)
9474 CREATE_BINEXPR_PARSER('-',                    EXPR_BINARY_SUB,                PREC_MULTIPLICATIVE, semantic_sub)
9475 CREATE_BINEXPR_PARSER(T_LESSLESS,             EXPR_BINARY_SHIFTLEFT,          PREC_ADDITIVE,       semantic_shift_op)
9476 CREATE_BINEXPR_PARSER(T_GREATERGREATER,       EXPR_BINARY_SHIFTRIGHT,         PREC_ADDITIVE,       semantic_shift_op)
9477 CREATE_BINEXPR_PARSER('<',                    EXPR_BINARY_LESS,               PREC_SHIFT,          semantic_comparison)
9478 CREATE_BINEXPR_PARSER('>',                    EXPR_BINARY_GREATER,            PREC_SHIFT,          semantic_comparison)
9479 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,          PREC_SHIFT,          semantic_comparison)
9480 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,       PREC_SHIFT,          semantic_comparison)
9481 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,           PREC_RELATIONAL,     semantic_comparison)
9482 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,              PREC_RELATIONAL,     semantic_comparison)
9483 CREATE_BINEXPR_PARSER('&',                    EXPR_BINARY_BITWISE_AND,        PREC_EQUALITY,       semantic_binexpr_arithmetic)
9484 CREATE_BINEXPR_PARSER('^',                    EXPR_BINARY_BITWISE_XOR,        PREC_AND,            semantic_binexpr_arithmetic)
9485 CREATE_BINEXPR_PARSER('|',                    EXPR_BINARY_BITWISE_OR,         PREC_XOR,            semantic_binexpr_arithmetic)
9486 CREATE_BINEXPR_PARSER(T_ANDAND,               EXPR_BINARY_LOGICAL_AND,        PREC_OR,             semantic_logical_op)
9487 CREATE_BINEXPR_PARSER(T_PIPEPIPE,             EXPR_BINARY_LOGICAL_OR,         PREC_LOGICAL_AND,    semantic_logical_op)
9488 CREATE_BINEXPR_PARSER('=',                    EXPR_BINARY_ASSIGN,             PREC_ASSIGNMENT,     semantic_binexpr_assign)
9489 CREATE_BINEXPR_PARSER(T_PLUSEQUAL,            EXPR_BINARY_ADD_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9490 CREATE_BINEXPR_PARSER(T_MINUSEQUAL,           EXPR_BINARY_SUB_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9491 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL,        EXPR_BINARY_MUL_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9492 CREATE_BINEXPR_PARSER(T_SLASHEQUAL,           EXPR_BINARY_DIV_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9493 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL,         EXPR_BINARY_MOD_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9494 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL,        EXPR_BINARY_SHIFTLEFT_ASSIGN,   PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9495 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL,  EXPR_BINARY_SHIFTRIGHT_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9496 CREATE_BINEXPR_PARSER(T_ANDEQUAL,             EXPR_BINARY_BITWISE_AND_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9497 CREATE_BINEXPR_PARSER(T_PIPEEQUAL,            EXPR_BINARY_BITWISE_OR_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9498 CREATE_BINEXPR_PARSER(T_CARETEQUAL,           EXPR_BINARY_BITWISE_XOR_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9499 CREATE_BINEXPR_PARSER(',',                    EXPR_BINARY_COMMA,              PREC_ASSIGNMENT,     semantic_comma)
9500
9501
9502 static expression_t *parse_sub_expression(precedence_t precedence)
9503 {
9504         if (token.type < 0) {
9505                 return expected_expression_error();
9506         }
9507
9508         expression_parser_function_t *parser
9509                 = &expression_parsers[token.type];
9510         source_position_t             source_position = token.source_position;
9511         expression_t                 *left;
9512
9513         if (parser->parser != NULL) {
9514                 left = parser->parser();
9515         } else {
9516                 left = parse_primary_expression();
9517         }
9518         assert(left != NULL);
9519         left->base.source_position = source_position;
9520
9521         while (true) {
9522                 if (token.type < 0) {
9523                         return expected_expression_error();
9524                 }
9525
9526                 parser = &expression_parsers[token.type];
9527                 if (parser->infix_parser == NULL)
9528                         break;
9529                 if (parser->infix_precedence < precedence)
9530                         break;
9531
9532                 left = parser->infix_parser(left);
9533
9534                 assert(left != NULL);
9535                 assert(left->kind != EXPR_UNKNOWN);
9536                 left->base.source_position = source_position;
9537         }
9538
9539         return left;
9540 }
9541
9542 /**
9543  * Parse an expression.
9544  */
9545 static expression_t *parse_expression(void)
9546 {
9547         return parse_sub_expression(PREC_EXPRESSION);
9548 }
9549
9550 /**
9551  * Register a parser for a prefix-like operator.
9552  *
9553  * @param parser      the parser function
9554  * @param token_type  the token type of the prefix token
9555  */
9556 static void register_expression_parser(parse_expression_function parser,
9557                                        int token_type)
9558 {
9559         expression_parser_function_t *entry = &expression_parsers[token_type];
9560
9561         if (entry->parser != NULL) {
9562                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9563                 panic("trying to register multiple expression parsers for a token");
9564         }
9565         entry->parser = parser;
9566 }
9567
9568 /**
9569  * Register a parser for an infix operator with given precedence.
9570  *
9571  * @param parser      the parser function
9572  * @param token_type  the token type of the infix operator
9573  * @param precedence  the precedence of the operator
9574  */
9575 static void register_infix_parser(parse_expression_infix_function parser,
9576                 int token_type, precedence_t precedence)
9577 {
9578         expression_parser_function_t *entry = &expression_parsers[token_type];
9579
9580         if (entry->infix_parser != NULL) {
9581                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9582                 panic("trying to register multiple infix expression parsers for a "
9583                       "token");
9584         }
9585         entry->infix_parser     = parser;
9586         entry->infix_precedence = precedence;
9587 }
9588
9589 /**
9590  * Initialize the expression parsers.
9591  */
9592 static void init_expression_parsers(void)
9593 {
9594         memset(&expression_parsers, 0, sizeof(expression_parsers));
9595
9596         register_infix_parser(parse_array_expression,               '[',                    PREC_POSTFIX);
9597         register_infix_parser(parse_call_expression,                '(',                    PREC_POSTFIX);
9598         register_infix_parser(parse_select_expression,              '.',                    PREC_POSTFIX);
9599         register_infix_parser(parse_select_expression,              T_MINUSGREATER,         PREC_POSTFIX);
9600         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,   T_PLUSPLUS,             PREC_POSTFIX);
9601         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,   T_MINUSMINUS,           PREC_POSTFIX);
9602         register_infix_parser(parse_EXPR_BINARY_MUL,                '*',                    PREC_MULTIPLICATIVE);
9603         register_infix_parser(parse_EXPR_BINARY_DIV,                '/',                    PREC_MULTIPLICATIVE);
9604         register_infix_parser(parse_EXPR_BINARY_MOD,                '%',                    PREC_MULTIPLICATIVE);
9605         register_infix_parser(parse_EXPR_BINARY_ADD,                '+',                    PREC_ADDITIVE);
9606         register_infix_parser(parse_EXPR_BINARY_SUB,                '-',                    PREC_ADDITIVE);
9607         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,          T_LESSLESS,             PREC_SHIFT);
9608         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,         T_GREATERGREATER,       PREC_SHIFT);
9609         register_infix_parser(parse_EXPR_BINARY_LESS,               '<',                    PREC_RELATIONAL);
9610         register_infix_parser(parse_EXPR_BINARY_GREATER,            '>',                    PREC_RELATIONAL);
9611         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,          T_LESSEQUAL,            PREC_RELATIONAL);
9612         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL,       T_GREATEREQUAL,         PREC_RELATIONAL);
9613         register_infix_parser(parse_EXPR_BINARY_EQUAL,              T_EQUALEQUAL,           PREC_EQUALITY);
9614         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,           T_EXCLAMATIONMARKEQUAL, PREC_EQUALITY);
9615         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,        '&',                    PREC_AND);
9616         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,        '^',                    PREC_XOR);
9617         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,         '|',                    PREC_OR);
9618         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,        T_ANDAND,               PREC_LOGICAL_AND);
9619         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,         T_PIPEPIPE,             PREC_LOGICAL_OR);
9620         register_infix_parser(parse_conditional_expression,         '?',                    PREC_CONDITIONAL);
9621         register_infix_parser(parse_EXPR_BINARY_ASSIGN,             '=',                    PREC_ASSIGNMENT);
9622         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,         T_PLUSEQUAL,            PREC_ASSIGNMENT);
9623         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,         T_MINUSEQUAL,           PREC_ASSIGNMENT);
9624         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,         T_ASTERISKEQUAL,        PREC_ASSIGNMENT);
9625         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,         T_SLASHEQUAL,           PREC_ASSIGNMENT);
9626         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,         T_PERCENTEQUAL,         PREC_ASSIGNMENT);
9627         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,   T_LESSLESSEQUAL,        PREC_ASSIGNMENT);
9628         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,  T_GREATERGREATEREQUAL,  PREC_ASSIGNMENT);
9629         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN, T_ANDEQUAL,             PREC_ASSIGNMENT);
9630         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,  T_PIPEEQUAL,            PREC_ASSIGNMENT);
9631         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN, T_CARETEQUAL,           PREC_ASSIGNMENT);
9632         register_infix_parser(parse_EXPR_BINARY_COMMA,              ',',                    PREC_EXPRESSION);
9633
9634         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-');
9635         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+');
9636         register_expression_parser(parse_EXPR_UNARY_NOT,              '!');
9637         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~');
9638         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*');
9639         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&');
9640         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT, T_PLUSPLUS);
9641         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT, T_MINUSMINUS);
9642         register_expression_parser(parse_sizeof,                      T_sizeof);
9643         register_expression_parser(parse_alignof,                     T___alignof__);
9644         register_expression_parser(parse_extension,                   T___extension__);
9645         register_expression_parser(parse_builtin_classify_type,       T___builtin_classify_type);
9646         register_expression_parser(parse_delete,                      T_delete);
9647         register_expression_parser(parse_throw,                       T_throw);
9648 }
9649
9650 /**
9651  * Parse a asm statement arguments specification.
9652  */
9653 static asm_argument_t *parse_asm_arguments(bool is_out)
9654 {
9655         asm_argument_t  *result = NULL;
9656         asm_argument_t **anchor = &result;
9657
9658         while (token.type == T_STRING_LITERAL || token.type == '[') {
9659                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
9660                 memset(argument, 0, sizeof(argument[0]));
9661
9662                 if (token.type == '[') {
9663                         eat('[');
9664                         if (token.type != T_IDENTIFIER) {
9665                                 parse_error_expected("while parsing asm argument",
9666                                                      T_IDENTIFIER, NULL);
9667                                 return NULL;
9668                         }
9669                         argument->symbol = token.v.symbol;
9670
9671                         expect(']', end_error);
9672                 }
9673
9674                 argument->constraints = parse_string_literals();
9675                 expect('(', end_error);
9676                 add_anchor_token(')');
9677                 expression_t *expression = parse_expression();
9678                 rem_anchor_token(')');
9679                 if (is_out) {
9680                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
9681                          * change size or type representation (e.g. int -> long is ok, but
9682                          * int -> float is not) */
9683                         if (expression->kind == EXPR_UNARY_CAST) {
9684                                 type_t      *const type = expression->base.type;
9685                                 type_kind_t  const kind = type->kind;
9686                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
9687                                         unsigned flags;
9688                                         unsigned size;
9689                                         if (kind == TYPE_ATOMIC) {
9690                                                 atomic_type_kind_t const akind = type->atomic.akind;
9691                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9692                                                 size  = get_atomic_type_size(akind);
9693                                         } else {
9694                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9695                                                 size  = get_atomic_type_size(get_intptr_kind());
9696                                         }
9697
9698                                         do {
9699                                                 expression_t *const value      = expression->unary.value;
9700                                                 type_t       *const value_type = value->base.type;
9701                                                 type_kind_t   const value_kind = value_type->kind;
9702
9703                                                 unsigned value_flags;
9704                                                 unsigned value_size;
9705                                                 if (value_kind == TYPE_ATOMIC) {
9706                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
9707                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9708                                                         value_size  = get_atomic_type_size(value_akind);
9709                                                 } else if (value_kind == TYPE_POINTER) {
9710                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9711                                                         value_size  = get_atomic_type_size(get_intptr_kind());
9712                                                 } else {
9713                                                         break;
9714                                                 }
9715
9716                                                 if (value_flags != flags || value_size != size)
9717                                                         break;
9718
9719                                                 expression = value;
9720                                         } while (expression->kind == EXPR_UNARY_CAST);
9721                                 }
9722                         }
9723
9724                         if (!is_lvalue(expression)) {
9725                                 errorf(&expression->base.source_position,
9726                                        "asm output argument is not an lvalue");
9727                         }
9728
9729                         if (argument->constraints.begin[0] == '+')
9730                                 mark_vars_read(expression, NULL);
9731                 } else {
9732                         mark_vars_read(expression, NULL);
9733                 }
9734                 argument->expression = expression;
9735                 expect(')', end_error);
9736
9737                 set_address_taken(expression, true);
9738
9739                 *anchor = argument;
9740                 anchor  = &argument->next;
9741
9742                 if (token.type != ',')
9743                         break;
9744                 eat(',');
9745         }
9746
9747         return result;
9748 end_error:
9749         return NULL;
9750 }
9751
9752 /**
9753  * Parse a asm statement clobber specification.
9754  */
9755 static asm_clobber_t *parse_asm_clobbers(void)
9756 {
9757         asm_clobber_t *result = NULL;
9758         asm_clobber_t *last   = NULL;
9759
9760         while (token.type == T_STRING_LITERAL) {
9761                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
9762                 clobber->clobber       = parse_string_literals();
9763
9764                 if (last != NULL) {
9765                         last->next = clobber;
9766                 } else {
9767                         result = clobber;
9768                 }
9769                 last = clobber;
9770
9771                 if (token.type != ',')
9772                         break;
9773                 eat(',');
9774         }
9775
9776         return result;
9777 }
9778
9779 /**
9780  * Parse an asm statement.
9781  */
9782 static statement_t *parse_asm_statement(void)
9783 {
9784         statement_t     *statement     = allocate_statement_zero(STATEMENT_ASM);
9785         asm_statement_t *asm_statement = &statement->asms;
9786
9787         eat(T_asm);
9788
9789         if (token.type == T_volatile) {
9790                 next_token();
9791                 asm_statement->is_volatile = true;
9792         }
9793
9794         expect('(', end_error);
9795         add_anchor_token(')');
9796         add_anchor_token(':');
9797         asm_statement->asm_text = parse_string_literals();
9798
9799         if (token.type != ':') {
9800                 rem_anchor_token(':');
9801                 goto end_of_asm;
9802         }
9803         eat(':');
9804
9805         asm_statement->outputs = parse_asm_arguments(true);
9806         if (token.type != ':') {
9807                 rem_anchor_token(':');
9808                 goto end_of_asm;
9809         }
9810         eat(':');
9811
9812         asm_statement->inputs = parse_asm_arguments(false);
9813         if (token.type != ':') {
9814                 rem_anchor_token(':');
9815                 goto end_of_asm;
9816         }
9817         rem_anchor_token(':');
9818         eat(':');
9819
9820         asm_statement->clobbers = parse_asm_clobbers();
9821
9822 end_of_asm:
9823         rem_anchor_token(')');
9824         expect(')', end_error);
9825         expect(';', end_error);
9826
9827         if (asm_statement->outputs == NULL) {
9828                 /* GCC: An 'asm' instruction without any output operands will be treated
9829                  * identically to a volatile 'asm' instruction. */
9830                 asm_statement->is_volatile = true;
9831         }
9832
9833         return statement;
9834 end_error:
9835         return create_invalid_statement();
9836 }
9837
9838 /**
9839  * Parse a case statement.
9840  */
9841 static statement_t *parse_case_statement(void)
9842 {
9843         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9844         source_position_t *const pos       = &statement->base.source_position;
9845
9846         eat(T_case);
9847
9848         expression_t *const expression   = parse_expression();
9849         statement->case_label.expression = expression;
9850         if (!is_constant_expression(expression)) {
9851                 /* This check does not prevent the error message in all cases of an
9852                  * prior error while parsing the expression.  At least it catches the
9853                  * common case of a mistyped enum entry. */
9854                 if (is_type_valid(skip_typeref(expression->base.type))) {
9855                         errorf(pos, "case label does not reduce to an integer constant");
9856                 }
9857                 statement->case_label.is_bad = true;
9858         } else {
9859                 long const val = fold_constant(expression);
9860                 statement->case_label.first_case = val;
9861                 statement->case_label.last_case  = val;
9862         }
9863
9864         if (GNU_MODE) {
9865                 if (token.type == T_DOTDOTDOT) {
9866                         next_token();
9867                         expression_t *const end_range   = parse_expression();
9868                         statement->case_label.end_range = end_range;
9869                         if (!is_constant_expression(end_range)) {
9870                                 /* This check does not prevent the error message in all cases of an
9871                                  * prior error while parsing the expression.  At least it catches the
9872                                  * common case of a mistyped enum entry. */
9873                                 if (is_type_valid(skip_typeref(end_range->base.type))) {
9874                                         errorf(pos, "case range does not reduce to an integer constant");
9875                                 }
9876                                 statement->case_label.is_bad = true;
9877                         } else {
9878                                 long const val = fold_constant(end_range);
9879                                 statement->case_label.last_case = val;
9880
9881                                 if (warning.other && val < statement->case_label.first_case) {
9882                                         statement->case_label.is_empty_range = true;
9883                                         warningf(pos, "empty range specified");
9884                                 }
9885                         }
9886                 }
9887         }
9888
9889         PUSH_PARENT(statement);
9890
9891         expect(':', end_error);
9892 end_error:
9893
9894         if (current_switch != NULL) {
9895                 if (! statement->case_label.is_bad) {
9896                         /* Check for duplicate case values */
9897                         case_label_statement_t *c = &statement->case_label;
9898                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
9899                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
9900                                         continue;
9901
9902                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
9903                                         continue;
9904
9905                                 errorf(pos, "duplicate case value (previously used %P)",
9906                                        &l->base.source_position);
9907                                 break;
9908                         }
9909                 }
9910                 /* link all cases into the switch statement */
9911                 if (current_switch->last_case == NULL) {
9912                         current_switch->first_case      = &statement->case_label;
9913                 } else {
9914                         current_switch->last_case->next = &statement->case_label;
9915                 }
9916                 current_switch->last_case = &statement->case_label;
9917         } else {
9918                 errorf(pos, "case label not within a switch statement");
9919         }
9920
9921         statement_t *const inner_stmt = parse_statement();
9922         statement->case_label.statement = inner_stmt;
9923         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9924                 errorf(&inner_stmt->base.source_position, "declaration after case label");
9925         }
9926
9927         POP_PARENT;
9928         return statement;
9929 }
9930
9931 /**
9932  * Parse a default statement.
9933  */
9934 static statement_t *parse_default_statement(void)
9935 {
9936         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9937
9938         eat(T_default);
9939
9940         PUSH_PARENT(statement);
9941
9942         expect(':', end_error);
9943         if (current_switch != NULL) {
9944                 const case_label_statement_t *def_label = current_switch->default_label;
9945                 if (def_label != NULL) {
9946                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
9947                                &def_label->base.source_position);
9948                 } else {
9949                         current_switch->default_label = &statement->case_label;
9950
9951                         /* link all cases into the switch statement */
9952                         if (current_switch->last_case == NULL) {
9953                                 current_switch->first_case      = &statement->case_label;
9954                         } else {
9955                                 current_switch->last_case->next = &statement->case_label;
9956                         }
9957                         current_switch->last_case = &statement->case_label;
9958                 }
9959         } else {
9960                 errorf(&statement->base.source_position,
9961                         "'default' label not within a switch statement");
9962         }
9963
9964         statement_t *const inner_stmt = parse_statement();
9965         statement->case_label.statement = inner_stmt;
9966         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9967                 errorf(&inner_stmt->base.source_position, "declaration after default label");
9968         }
9969
9970         POP_PARENT;
9971         return statement;
9972 end_error:
9973         POP_PARENT;
9974         return create_invalid_statement();
9975 }
9976
9977 /**
9978  * Parse a label statement.
9979  */
9980 static statement_t *parse_label_statement(void)
9981 {
9982         assert(token.type == T_IDENTIFIER);
9983         symbol_t *symbol = token.v.symbol;
9984         label_t  *label  = get_label(symbol);
9985
9986         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
9987         statement->label.label       = label;
9988
9989         next_token();
9990
9991         PUSH_PARENT(statement);
9992
9993         /* if statement is already set then the label is defined twice,
9994          * otherwise it was just mentioned in a goto/local label declaration so far
9995          */
9996         if (label->statement != NULL) {
9997                 errorf(HERE, "duplicate label '%Y' (declared %P)",
9998                        symbol, &label->base.source_position);
9999         } else {
10000                 label->base.source_position = token.source_position;
10001                 label->statement            = statement;
10002         }
10003
10004         eat(':');
10005
10006         if (token.type == '}') {
10007                 /* TODO only warn? */
10008                 if (warning.other && false) {
10009                         warningf(HERE, "label at end of compound statement");
10010                         statement->label.statement = create_empty_statement();
10011                 } else {
10012                         errorf(HERE, "label at end of compound statement");
10013                         statement->label.statement = create_invalid_statement();
10014                 }
10015         } else if (token.type == ';') {
10016                 /* Eat an empty statement here, to avoid the warning about an empty
10017                  * statement after a label.  label:; is commonly used to have a label
10018                  * before a closing brace. */
10019                 statement->label.statement = create_empty_statement();
10020                 next_token();
10021         } else {
10022                 statement_t *const inner_stmt = parse_statement();
10023                 statement->label.statement = inner_stmt;
10024                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
10025                         errorf(&inner_stmt->base.source_position, "declaration after label");
10026                 }
10027         }
10028
10029         /* remember the labels in a list for later checking */
10030         *label_anchor = &statement->label;
10031         label_anchor  = &statement->label.next;
10032
10033         POP_PARENT;
10034         return statement;
10035 }
10036
10037 /**
10038  * Parse an if statement.
10039  */
10040 static statement_t *parse_if(void)
10041 {
10042         statement_t *statement = allocate_statement_zero(STATEMENT_IF);
10043
10044         eat(T_if);
10045
10046         PUSH_PARENT(statement);
10047
10048         add_anchor_token('{');
10049
10050         expect('(', end_error);
10051         add_anchor_token(')');
10052         expression_t *const expr = parse_expression();
10053         statement->ifs.condition = expr;
10054         /* §6.8.4.1:1  The controlling expression of an if statement shall have
10055          *             scalar type. */
10056         semantic_condition(expr, "condition of 'if'-statment");
10057         mark_vars_read(expr, NULL);
10058         rem_anchor_token(')');
10059         expect(')', end_error);
10060
10061 end_error:
10062         rem_anchor_token('{');
10063
10064         add_anchor_token(T_else);
10065         statement_t *const true_stmt = parse_statement();
10066         statement->ifs.true_statement = true_stmt;
10067         rem_anchor_token(T_else);
10068
10069         if (token.type == T_else) {
10070                 next_token();
10071                 statement->ifs.false_statement = parse_statement();
10072         } else if (warning.parentheses &&
10073                         true_stmt->kind == STATEMENT_IF &&
10074                         true_stmt->ifs.false_statement != NULL) {
10075                 warningf(&true_stmt->base.source_position,
10076                                 "suggest explicit braces to avoid ambiguous 'else'");
10077         }
10078
10079         POP_PARENT;
10080         return statement;
10081 }
10082
10083 /**
10084  * Check that all enums are handled in a switch.
10085  *
10086  * @param statement  the switch statement to check
10087  */
10088 static void check_enum_cases(const switch_statement_t *statement) {
10089         const type_t *type = skip_typeref(statement->expression->base.type);
10090         if (! is_type_enum(type))
10091                 return;
10092         const enum_type_t *enumt = &type->enumt;
10093
10094         /* if we have a default, no warnings */
10095         if (statement->default_label != NULL)
10096                 return;
10097
10098         /* FIXME: calculation of value should be done while parsing */
10099         /* TODO: quadratic algorithm here. Change to an n log n one */
10100         long            last_value = -1;
10101         const entity_t *entry      = enumt->enume->base.next;
10102         for (; entry != NULL && entry->kind == ENTITY_ENUM_VALUE;
10103              entry = entry->base.next) {
10104                 const expression_t *expression = entry->enum_value.value;
10105                 long                value      = expression != NULL ? fold_constant(expression) : last_value + 1;
10106                 bool                found      = false;
10107                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
10108                         if (l->expression == NULL)
10109                                 continue;
10110                         if (l->first_case <= value && value <= l->last_case) {
10111                                 found = true;
10112                                 break;
10113                         }
10114                 }
10115                 if (! found) {
10116                         warningf(&statement->base.source_position,
10117                                  "enumeration value '%Y' not handled in switch",
10118                                  entry->base.symbol);
10119                 }
10120                 last_value = value;
10121         }
10122 }
10123
10124 /**
10125  * Parse a switch statement.
10126  */
10127 static statement_t *parse_switch(void)
10128 {
10129         statement_t *statement = allocate_statement_zero(STATEMENT_SWITCH);
10130
10131         eat(T_switch);
10132
10133         PUSH_PARENT(statement);
10134
10135         expect('(', end_error);
10136         add_anchor_token(')');
10137         expression_t *const expr = parse_expression();
10138         mark_vars_read(expr, NULL);
10139         type_t       *      type = skip_typeref(expr->base.type);
10140         if (is_type_integer(type)) {
10141                 type = promote_integer(type);
10142                 if (warning.traditional) {
10143                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
10144                                 warningf(&expr->base.source_position,
10145                                         "'%T' switch expression not converted to '%T' in ISO C",
10146                                         type, type_int);
10147                         }
10148                 }
10149         } else if (is_type_valid(type)) {
10150                 errorf(&expr->base.source_position,
10151                        "switch quantity is not an integer, but '%T'", type);
10152                 type = type_error_type;
10153         }
10154         statement->switchs.expression = create_implicit_cast(expr, type);
10155         expect(')', end_error);
10156         rem_anchor_token(')');
10157
10158         switch_statement_t *rem = current_switch;
10159         current_switch          = &statement->switchs;
10160         statement->switchs.body = parse_statement();
10161         current_switch          = rem;
10162
10163         if (warning.switch_default &&
10164             statement->switchs.default_label == NULL) {
10165                 warningf(&statement->base.source_position, "switch has no default case");
10166         }
10167         if (warning.switch_enum)
10168                 check_enum_cases(&statement->switchs);
10169
10170         POP_PARENT;
10171         return statement;
10172 end_error:
10173         POP_PARENT;
10174         return create_invalid_statement();
10175 }
10176
10177 static statement_t *parse_loop_body(statement_t *const loop)
10178 {
10179         statement_t *const rem = current_loop;
10180         current_loop = loop;
10181
10182         statement_t *const body = parse_statement();
10183
10184         current_loop = rem;
10185         return body;
10186 }
10187
10188 /**
10189  * Parse a while statement.
10190  */
10191 static statement_t *parse_while(void)
10192 {
10193         statement_t *statement = allocate_statement_zero(STATEMENT_WHILE);
10194
10195         eat(T_while);
10196
10197         PUSH_PARENT(statement);
10198
10199         expect('(', end_error);
10200         add_anchor_token(')');
10201         expression_t *const cond = parse_expression();
10202         statement->whiles.condition = cond;
10203         /* §6.8.5:2    The controlling expression of an iteration statement shall
10204          *             have scalar type. */
10205         semantic_condition(cond, "condition of 'while'-statement");
10206         mark_vars_read(cond, NULL);
10207         rem_anchor_token(')');
10208         expect(')', end_error);
10209
10210         statement->whiles.body = parse_loop_body(statement);
10211
10212         POP_PARENT;
10213         return statement;
10214 end_error:
10215         POP_PARENT;
10216         return create_invalid_statement();
10217 }
10218
10219 /**
10220  * Parse a do statement.
10221  */
10222 static statement_t *parse_do(void)
10223 {
10224         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
10225
10226         eat(T_do);
10227
10228         PUSH_PARENT(statement);
10229
10230         add_anchor_token(T_while);
10231         statement->do_while.body = parse_loop_body(statement);
10232         rem_anchor_token(T_while);
10233
10234         expect(T_while, end_error);
10235         expect('(', end_error);
10236         add_anchor_token(')');
10237         expression_t *const cond = parse_expression();
10238         statement->do_while.condition = cond;
10239         /* §6.8.5:2    The controlling expression of an iteration statement shall
10240          *             have scalar type. */
10241         semantic_condition(cond, "condition of 'do-while'-statement");
10242         mark_vars_read(cond, NULL);
10243         rem_anchor_token(')');
10244         expect(')', end_error);
10245         expect(';', end_error);
10246
10247         POP_PARENT;
10248         return statement;
10249 end_error:
10250         POP_PARENT;
10251         return create_invalid_statement();
10252 }
10253
10254 /**
10255  * Parse a for statement.
10256  */
10257 static statement_t *parse_for(void)
10258 {
10259         statement_t *statement = allocate_statement_zero(STATEMENT_FOR);
10260
10261         eat(T_for);
10262
10263         expect('(', end_error1);
10264         add_anchor_token(')');
10265
10266         PUSH_PARENT(statement);
10267
10268         size_t const  top       = environment_top();
10269         scope_t      *old_scope = scope_push(&statement->fors.scope);
10270
10271         if (token.type == ';') {
10272                 next_token();
10273         } else if (is_declaration_specifier(&token, false)) {
10274                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10275         } else {
10276                 add_anchor_token(';');
10277                 expression_t *const init = parse_expression();
10278                 statement->fors.initialisation = init;
10279                 mark_vars_read(init, ENT_ANY);
10280                 if (warning.unused_value && !expression_has_effect(init)) {
10281                         warningf(&init->base.source_position,
10282                                         "initialisation of 'for'-statement has no effect");
10283                 }
10284                 rem_anchor_token(';');
10285                 expect(';', end_error2);
10286         }
10287
10288         if (token.type != ';') {
10289                 add_anchor_token(';');
10290                 expression_t *const cond = parse_expression();
10291                 statement->fors.condition = cond;
10292                 /* §6.8.5:2    The controlling expression of an iteration statement
10293                  *             shall have scalar type. */
10294                 semantic_condition(cond, "condition of 'for'-statement");
10295                 mark_vars_read(cond, NULL);
10296                 rem_anchor_token(';');
10297         }
10298         expect(';', end_error2);
10299         if (token.type != ')') {
10300                 expression_t *const step = parse_expression();
10301                 statement->fors.step = step;
10302                 mark_vars_read(step, ENT_ANY);
10303                 if (warning.unused_value && !expression_has_effect(step)) {
10304                         warningf(&step->base.source_position,
10305                                  "step of 'for'-statement has no effect");
10306                 }
10307         }
10308         expect(')', end_error2);
10309         rem_anchor_token(')');
10310         statement->fors.body = parse_loop_body(statement);
10311
10312         assert(current_scope == &statement->fors.scope);
10313         scope_pop(old_scope);
10314         environment_pop_to(top);
10315
10316         POP_PARENT;
10317         return statement;
10318
10319 end_error2:
10320         POP_PARENT;
10321         rem_anchor_token(')');
10322         assert(current_scope == &statement->fors.scope);
10323         scope_pop(old_scope);
10324         environment_pop_to(top);
10325         /* fallthrough */
10326
10327 end_error1:
10328         return create_invalid_statement();
10329 }
10330
10331 /**
10332  * Parse a goto statement.
10333  */
10334 static statement_t *parse_goto(void)
10335 {
10336         statement_t *statement = allocate_statement_zero(STATEMENT_GOTO);
10337         eat(T_goto);
10338
10339         if (GNU_MODE && token.type == '*') {
10340                 next_token();
10341                 expression_t *expression = parse_expression();
10342                 mark_vars_read(expression, NULL);
10343
10344                 /* Argh: although documentation says the expression must be of type void*,
10345                  * gcc accepts anything that can be casted into void* without error */
10346                 type_t *type = expression->base.type;
10347
10348                 if (type != type_error_type) {
10349                         if (!is_type_pointer(type) && !is_type_integer(type)) {
10350                                 errorf(&expression->base.source_position,
10351                                         "cannot convert to a pointer type");
10352                         } else if (warning.other && type != type_void_ptr) {
10353                                 warningf(&expression->base.source_position,
10354                                         "type of computed goto expression should be 'void*' not '%T'", type);
10355                         }
10356                         expression = create_implicit_cast(expression, type_void_ptr);
10357                 }
10358
10359                 statement->gotos.expression = expression;
10360         } else {
10361                 if (token.type != T_IDENTIFIER) {
10362                         if (GNU_MODE)
10363                                 parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
10364                         else
10365                                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
10366                         eat_until_anchor();
10367                         goto end_error;
10368                 }
10369                 symbol_t *symbol = token.v.symbol;
10370                 next_token();
10371
10372                 statement->gotos.label = get_label(symbol);
10373         }
10374
10375         /* remember the goto's in a list for later checking */
10376         *goto_anchor = &statement->gotos;
10377         goto_anchor  = &statement->gotos.next;
10378
10379         expect(';', end_error);
10380
10381         return statement;
10382 end_error:
10383         return create_invalid_statement();
10384 }
10385
10386 /**
10387  * Parse a continue statement.
10388  */
10389 static statement_t *parse_continue(void)
10390 {
10391         if (current_loop == NULL) {
10392                 errorf(HERE, "continue statement not within loop");
10393         }
10394
10395         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
10396
10397         eat(T_continue);
10398         expect(';', end_error);
10399
10400 end_error:
10401         return statement;
10402 }
10403
10404 /**
10405  * Parse a break statement.
10406  */
10407 static statement_t *parse_break(void)
10408 {
10409         if (current_switch == NULL && current_loop == NULL) {
10410                 errorf(HERE, "break statement not within loop or switch");
10411         }
10412
10413         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
10414
10415         eat(T_break);
10416         expect(';', end_error);
10417
10418 end_error:
10419         return statement;
10420 }
10421
10422 /**
10423  * Parse a __leave statement.
10424  */
10425 static statement_t *parse_leave_statement(void)
10426 {
10427         if (current_try == NULL) {
10428                 errorf(HERE, "__leave statement not within __try");
10429         }
10430
10431         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
10432
10433         eat(T___leave);
10434         expect(';', end_error);
10435
10436 end_error:
10437         return statement;
10438 }
10439
10440 /**
10441  * Check if a given entity represents a local variable.
10442  */
10443 static bool is_local_variable(const entity_t *entity)
10444 {
10445         if (entity->kind != ENTITY_VARIABLE)
10446                 return false;
10447
10448         switch ((storage_class_tag_t) entity->declaration.storage_class) {
10449         case STORAGE_CLASS_AUTO:
10450         case STORAGE_CLASS_REGISTER: {
10451                 const type_t *type = skip_typeref(entity->declaration.type);
10452                 if (is_type_function(type)) {
10453                         return false;
10454                 } else {
10455                         return true;
10456                 }
10457         }
10458         default:
10459                 return false;
10460         }
10461 }
10462
10463 /**
10464  * Check if a given expression represents a local variable.
10465  */
10466 static bool expression_is_local_variable(const expression_t *expression)
10467 {
10468         if (expression->base.kind != EXPR_REFERENCE) {
10469                 return false;
10470         }
10471         const entity_t *entity = expression->reference.entity;
10472         return is_local_variable(entity);
10473 }
10474
10475 /**
10476  * Check if a given expression represents a local variable and
10477  * return its declaration then, else return NULL.
10478  */
10479 entity_t *expression_is_variable(const expression_t *expression)
10480 {
10481         if (expression->base.kind != EXPR_REFERENCE) {
10482                 return NULL;
10483         }
10484         entity_t *entity = expression->reference.entity;
10485         if (entity->kind != ENTITY_VARIABLE)
10486                 return NULL;
10487
10488         return entity;
10489 }
10490
10491 /**
10492  * Parse a return statement.
10493  */
10494 static statement_t *parse_return(void)
10495 {
10496         eat(T_return);
10497
10498         statement_t *statement = allocate_statement_zero(STATEMENT_RETURN);
10499
10500         expression_t *return_value = NULL;
10501         if (token.type != ';') {
10502                 return_value = parse_expression();
10503                 mark_vars_read(return_value, NULL);
10504         }
10505
10506         const type_t *const func_type = skip_typeref(current_function->base.type);
10507         assert(is_type_function(func_type));
10508         type_t *const return_type = skip_typeref(func_type->function.return_type);
10509
10510         source_position_t const *const pos = &statement->base.source_position;
10511         if (return_value != NULL) {
10512                 type_t *return_value_type = skip_typeref(return_value->base.type);
10513
10514                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10515                         if (is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
10516                                 /* ISO/IEC 14882:1998(E) §6.6.3:2 */
10517                                 /* Only warn in C mode, because GCC does the same */
10518                                 if (c_mode & _CXX || strict_mode) {
10519                                         errorf(pos,
10520                                                         "'return' with a value, in function returning 'void'");
10521                                 } else if (warning.other) {
10522                                         warningf(pos,
10523                                                         "'return' with a value, in function returning 'void'");
10524                                 }
10525                         } else if (!(c_mode & _CXX)) { /* ISO/IEC 14882:1998(E) §6.6.3:3 */
10526                                 /* Only warn in C mode, because GCC does the same */
10527                                 if (strict_mode) {
10528                                         errorf(pos,
10529                                                         "'return' with expression in function return 'void'");
10530                                 } else if (warning.other) {
10531                                         warningf(pos,
10532                                                         "'return' with expression in function return 'void'");
10533                                 }
10534                         }
10535                 } else {
10536                         assign_error_t error = semantic_assign(return_type, return_value);
10537                         report_assign_error(error, return_type, return_value, "'return'",
10538                                         pos);
10539                 }
10540                 return_value = create_implicit_cast(return_value, return_type);
10541                 /* check for returning address of a local var */
10542                 if (warning.other && return_value != NULL
10543                                 && return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
10544                         const expression_t *expression = return_value->unary.value;
10545                         if (expression_is_local_variable(expression)) {
10546                                 warningf(pos, "function returns address of local variable");
10547                         }
10548                 }
10549         } else if (warning.other && !is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10550                 /* ISO/IEC 14882:1998(E) §6.6.3:3 */
10551                 if (c_mode & _CXX || strict_mode) {
10552                         errorf(pos,
10553                                         "'return' without value, in function returning non-void");
10554                 } else {
10555                         warningf(pos,
10556                                         "'return' without value, in function returning non-void");
10557                 }
10558         }
10559         statement->returns.value = return_value;
10560
10561         expect(';', end_error);
10562
10563 end_error:
10564         return statement;
10565 }
10566
10567 /**
10568  * Parse a declaration statement.
10569  */
10570 static statement_t *parse_declaration_statement(void)
10571 {
10572         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10573
10574         entity_t *before = current_scope->last_entity;
10575         if (GNU_MODE) {
10576                 parse_external_declaration();
10577         } else {
10578                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10579         }
10580
10581         if (before == NULL) {
10582                 statement->declaration.declarations_begin = current_scope->entities;
10583         } else {
10584                 statement->declaration.declarations_begin = before->base.next;
10585         }
10586         statement->declaration.declarations_end = current_scope->last_entity;
10587
10588         return statement;
10589 }
10590
10591 /**
10592  * Parse an expression statement, ie. expr ';'.
10593  */
10594 static statement_t *parse_expression_statement(void)
10595 {
10596         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10597
10598         expression_t *const expr         = parse_expression();
10599         statement->expression.expression = expr;
10600         mark_vars_read(expr, ENT_ANY);
10601
10602         expect(';', end_error);
10603
10604 end_error:
10605         return statement;
10606 }
10607
10608 /**
10609  * Parse a microsoft __try { } __finally { } or
10610  * __try{ } __except() { }
10611  */
10612 static statement_t *parse_ms_try_statment(void)
10613 {
10614         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
10615         eat(T___try);
10616
10617         PUSH_PARENT(statement);
10618
10619         ms_try_statement_t *rem = current_try;
10620         current_try = &statement->ms_try;
10621         statement->ms_try.try_statement = parse_compound_statement(false);
10622         current_try = rem;
10623
10624         POP_PARENT;
10625
10626         if (token.type == T___except) {
10627                 eat(T___except);
10628                 expect('(', end_error);
10629                 add_anchor_token(')');
10630                 expression_t *const expr = parse_expression();
10631                 mark_vars_read(expr, NULL);
10632                 type_t       *      type = skip_typeref(expr->base.type);
10633                 if (is_type_integer(type)) {
10634                         type = promote_integer(type);
10635                 } else if (is_type_valid(type)) {
10636                         errorf(&expr->base.source_position,
10637                                "__expect expression is not an integer, but '%T'", type);
10638                         type = type_error_type;
10639                 }
10640                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
10641                 rem_anchor_token(')');
10642                 expect(')', end_error);
10643                 statement->ms_try.final_statement = parse_compound_statement(false);
10644         } else if (token.type == T__finally) {
10645                 eat(T___finally);
10646                 statement->ms_try.final_statement = parse_compound_statement(false);
10647         } else {
10648                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
10649                 return create_invalid_statement();
10650         }
10651         return statement;
10652 end_error:
10653         return create_invalid_statement();
10654 }
10655
10656 static statement_t *parse_empty_statement(void)
10657 {
10658         if (warning.empty_statement) {
10659                 warningf(HERE, "statement is empty");
10660         }
10661         statement_t *const statement = create_empty_statement();
10662         eat(';');
10663         return statement;
10664 }
10665
10666 static statement_t *parse_local_label_declaration(void)
10667 {
10668         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10669
10670         eat(T___label__);
10671
10672         entity_t *begin = NULL, *end = NULL;
10673
10674         while (true) {
10675                 if (token.type != T_IDENTIFIER) {
10676                         parse_error_expected("while parsing local label declaration",
10677                                 T_IDENTIFIER, NULL);
10678                         goto end_error;
10679                 }
10680                 symbol_t *symbol = token.v.symbol;
10681                 entity_t *entity = get_entity(symbol, NAMESPACE_LABEL);
10682                 if (entity != NULL && entity->base.parent_scope == current_scope) {
10683                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition %P)",
10684                                symbol, &entity->base.source_position);
10685                 } else {
10686                         entity = allocate_entity_zero(ENTITY_LOCAL_LABEL);
10687
10688                         entity->base.parent_scope    = current_scope;
10689                         entity->base.namespc         = NAMESPACE_LABEL;
10690                         entity->base.source_position = token.source_position;
10691                         entity->base.symbol          = symbol;
10692
10693                         if (end != NULL)
10694                                 end->base.next = entity;
10695                         end = entity;
10696                         if (begin == NULL)
10697                                 begin = entity;
10698
10699                         environment_push(entity);
10700                 }
10701                 next_token();
10702
10703                 if (token.type != ',')
10704                         break;
10705                 next_token();
10706         }
10707         eat(';');
10708 end_error:
10709         statement->declaration.declarations_begin = begin;
10710         statement->declaration.declarations_end   = end;
10711         return statement;
10712 }
10713
10714 static void parse_namespace_definition(void)
10715 {
10716         eat(T_namespace);
10717
10718         entity_t *entity = NULL;
10719         symbol_t *symbol = NULL;
10720
10721         if (token.type == T_IDENTIFIER) {
10722                 symbol = token.v.symbol;
10723                 next_token();
10724
10725                 entity = get_entity(symbol, NAMESPACE_NORMAL);
10726                 if (entity != NULL && entity->kind != ENTITY_NAMESPACE
10727                                 && entity->base.parent_scope == current_scope) {
10728                         error_redefined_as_different_kind(&token.source_position,
10729                                                           entity, ENTITY_NAMESPACE);
10730                         entity = NULL;
10731                 }
10732         }
10733
10734         if (entity == NULL) {
10735                 entity                       = allocate_entity_zero(ENTITY_NAMESPACE);
10736                 entity->base.symbol          = symbol;
10737                 entity->base.source_position = token.source_position;
10738                 entity->base.namespc         = NAMESPACE_NORMAL;
10739                 entity->base.parent_scope    = current_scope;
10740         }
10741
10742         if (token.type == '=') {
10743                 /* TODO: parse namespace alias */
10744                 panic("namespace alias definition not supported yet");
10745         }
10746
10747         environment_push(entity);
10748         append_entity(current_scope, entity);
10749
10750         size_t const  top       = environment_top();
10751         scope_t      *old_scope = scope_push(&entity->namespacee.members);
10752
10753         expect('{', end_error);
10754         parse_externals();
10755         expect('}', end_error);
10756
10757 end_error:
10758         assert(current_scope == &entity->namespacee.members);
10759         scope_pop(old_scope);
10760         environment_pop_to(top);
10761 }
10762
10763 /**
10764  * Parse a statement.
10765  * There's also parse_statement() which additionally checks for
10766  * "statement has no effect" warnings
10767  */
10768 static statement_t *intern_parse_statement(void)
10769 {
10770         statement_t *statement = NULL;
10771
10772         /* declaration or statement */
10773         add_anchor_token(';');
10774         switch (token.type) {
10775         case T_IDENTIFIER: {
10776                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
10777                 if (la1_type == ':') {
10778                         statement = parse_label_statement();
10779                 } else if (is_typedef_symbol(token.v.symbol)) {
10780                         statement = parse_declaration_statement();
10781                 } else {
10782                         /* it's an identifier, the grammar says this must be an
10783                          * expression statement. However it is common that users mistype
10784                          * declaration types, so we guess a bit here to improve robustness
10785                          * for incorrect programs */
10786                         switch (la1_type) {
10787                         case '&':
10788                         case '*':
10789                                 if (get_entity(token.v.symbol, NAMESPACE_NORMAL) != NULL)
10790                                         goto expression_statment;
10791                                 /* FALLTHROUGH */
10792
10793                         DECLARATION_START
10794                         case T_IDENTIFIER:
10795                                 statement = parse_declaration_statement();
10796                                 break;
10797
10798                         default:
10799 expression_statment:
10800                                 statement = parse_expression_statement();
10801                                 break;
10802                         }
10803                 }
10804                 break;
10805         }
10806
10807         case T___extension__:
10808                 /* This can be a prefix to a declaration or an expression statement.
10809                  * We simply eat it now and parse the rest with tail recursion. */
10810                 do {
10811                         next_token();
10812                 } while (token.type == T___extension__);
10813                 bool old_gcc_extension = in_gcc_extension;
10814                 in_gcc_extension       = true;
10815                 statement = intern_parse_statement();
10816                 in_gcc_extension = old_gcc_extension;
10817                 break;
10818
10819         DECLARATION_START
10820                 statement = parse_declaration_statement();
10821                 break;
10822
10823         case T___label__:
10824                 statement = parse_local_label_declaration();
10825                 break;
10826
10827         case ';':         statement = parse_empty_statement();         break;
10828         case '{':         statement = parse_compound_statement(false); break;
10829         case T___leave:   statement = parse_leave_statement();         break;
10830         case T___try:     statement = parse_ms_try_statment();         break;
10831         case T_asm:       statement = parse_asm_statement();           break;
10832         case T_break:     statement = parse_break();                   break;
10833         case T_case:      statement = parse_case_statement();          break;
10834         case T_continue:  statement = parse_continue();                break;
10835         case T_default:   statement = parse_default_statement();       break;
10836         case T_do:        statement = parse_do();                      break;
10837         case T_for:       statement = parse_for();                     break;
10838         case T_goto:      statement = parse_goto();                    break;
10839         case T_if:        statement = parse_if();                      break;
10840         case T_return:    statement = parse_return();                  break;
10841         case T_switch:    statement = parse_switch();                  break;
10842         case T_while:     statement = parse_while();                   break;
10843
10844         EXPRESSION_START
10845                 statement = parse_expression_statement();
10846                 break;
10847
10848         default:
10849                 errorf(HERE, "unexpected token %K while parsing statement", &token);
10850                 statement = create_invalid_statement();
10851                 if (!at_anchor())
10852                         next_token();
10853                 break;
10854         }
10855         rem_anchor_token(';');
10856
10857         assert(statement != NULL
10858                         && statement->base.source_position.input_name != NULL);
10859
10860         return statement;
10861 }
10862
10863 /**
10864  * parse a statement and emits "statement has no effect" warning if needed
10865  * (This is really a wrapper around intern_parse_statement with check for 1
10866  *  single warning. It is needed, because for statement expressions we have
10867  *  to avoid the warning on the last statement)
10868  */
10869 static statement_t *parse_statement(void)
10870 {
10871         statement_t *statement = intern_parse_statement();
10872
10873         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
10874                 expression_t *expression = statement->expression.expression;
10875                 if (!expression_has_effect(expression)) {
10876                         warningf(&expression->base.source_position,
10877                                         "statement has no effect");
10878                 }
10879         }
10880
10881         return statement;
10882 }
10883
10884 /**
10885  * Parse a compound statement.
10886  */
10887 static statement_t *parse_compound_statement(bool inside_expression_statement)
10888 {
10889         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
10890
10891         PUSH_PARENT(statement);
10892
10893         eat('{');
10894         add_anchor_token('}');
10895         /* tokens, which can start a statement */
10896         /* TODO MS, __builtin_FOO */
10897         add_anchor_token('!');
10898         add_anchor_token('&');
10899         add_anchor_token('(');
10900         add_anchor_token('*');
10901         add_anchor_token('+');
10902         add_anchor_token('-');
10903         add_anchor_token('{');
10904         add_anchor_token('~');
10905         add_anchor_token(T_CHARACTER_CONSTANT);
10906         add_anchor_token(T_COLONCOLON);
10907         add_anchor_token(T_FLOATINGPOINT);
10908         add_anchor_token(T_IDENTIFIER);
10909         add_anchor_token(T_INTEGER);
10910         add_anchor_token(T_MINUSMINUS);
10911         add_anchor_token(T_PLUSPLUS);
10912         add_anchor_token(T_STRING_LITERAL);
10913         add_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10914         add_anchor_token(T_WIDE_STRING_LITERAL);
10915         add_anchor_token(T__Bool);
10916         add_anchor_token(T__Complex);
10917         add_anchor_token(T__Imaginary);
10918         add_anchor_token(T___FUNCTION__);
10919         add_anchor_token(T___PRETTY_FUNCTION__);
10920         add_anchor_token(T___alignof__);
10921         add_anchor_token(T___attribute__);
10922         add_anchor_token(T___builtin_va_start);
10923         add_anchor_token(T___extension__);
10924         add_anchor_token(T___func__);
10925         add_anchor_token(T___imag__);
10926         add_anchor_token(T___label__);
10927         add_anchor_token(T___real__);
10928         add_anchor_token(T___thread);
10929         add_anchor_token(T_asm);
10930         add_anchor_token(T_auto);
10931         add_anchor_token(T_bool);
10932         add_anchor_token(T_break);
10933         add_anchor_token(T_case);
10934         add_anchor_token(T_char);
10935         add_anchor_token(T_class);
10936         add_anchor_token(T_const);
10937         add_anchor_token(T_const_cast);
10938         add_anchor_token(T_continue);
10939         add_anchor_token(T_default);
10940         add_anchor_token(T_delete);
10941         add_anchor_token(T_double);
10942         add_anchor_token(T_do);
10943         add_anchor_token(T_dynamic_cast);
10944         add_anchor_token(T_enum);
10945         add_anchor_token(T_extern);
10946         add_anchor_token(T_false);
10947         add_anchor_token(T_float);
10948         add_anchor_token(T_for);
10949         add_anchor_token(T_goto);
10950         add_anchor_token(T_if);
10951         add_anchor_token(T_inline);
10952         add_anchor_token(T_int);
10953         add_anchor_token(T_long);
10954         add_anchor_token(T_new);
10955         add_anchor_token(T_operator);
10956         add_anchor_token(T_register);
10957         add_anchor_token(T_reinterpret_cast);
10958         add_anchor_token(T_restrict);
10959         add_anchor_token(T_return);
10960         add_anchor_token(T_short);
10961         add_anchor_token(T_signed);
10962         add_anchor_token(T_sizeof);
10963         add_anchor_token(T_static);
10964         add_anchor_token(T_static_cast);
10965         add_anchor_token(T_struct);
10966         add_anchor_token(T_switch);
10967         add_anchor_token(T_template);
10968         add_anchor_token(T_this);
10969         add_anchor_token(T_throw);
10970         add_anchor_token(T_true);
10971         add_anchor_token(T_try);
10972         add_anchor_token(T_typedef);
10973         add_anchor_token(T_typeid);
10974         add_anchor_token(T_typename);
10975         add_anchor_token(T_typeof);
10976         add_anchor_token(T_union);
10977         add_anchor_token(T_unsigned);
10978         add_anchor_token(T_using);
10979         add_anchor_token(T_void);
10980         add_anchor_token(T_volatile);
10981         add_anchor_token(T_wchar_t);
10982         add_anchor_token(T_while);
10983
10984         size_t const  top       = environment_top();
10985         scope_t      *old_scope = scope_push(&statement->compound.scope);
10986
10987         statement_t **anchor            = &statement->compound.statements;
10988         bool          only_decls_so_far = true;
10989         while (token.type != '}') {
10990                 if (token.type == T_EOF) {
10991                         errorf(&statement->base.source_position,
10992                                "EOF while parsing compound statement");
10993                         break;
10994                 }
10995                 statement_t *sub_statement = intern_parse_statement();
10996                 if (is_invalid_statement(sub_statement)) {
10997                         /* an error occurred. if we are at an anchor, return */
10998                         if (at_anchor())
10999                                 goto end_error;
11000                         continue;
11001                 }
11002
11003                 if (warning.declaration_after_statement) {
11004                         if (sub_statement->kind != STATEMENT_DECLARATION) {
11005                                 only_decls_so_far = false;
11006                         } else if (!only_decls_so_far) {
11007                                 warningf(&sub_statement->base.source_position,
11008                                          "ISO C90 forbids mixed declarations and code");
11009                         }
11010                 }
11011
11012                 *anchor = sub_statement;
11013
11014                 while (sub_statement->base.next != NULL)
11015                         sub_statement = sub_statement->base.next;
11016
11017                 anchor = &sub_statement->base.next;
11018         }
11019         next_token();
11020
11021         /* look over all statements again to produce no effect warnings */
11022         if (warning.unused_value) {
11023                 statement_t *sub_statement = statement->compound.statements;
11024                 for (; sub_statement != NULL; sub_statement = sub_statement->base.next) {
11025                         if (sub_statement->kind != STATEMENT_EXPRESSION)
11026                                 continue;
11027                         /* don't emit a warning for the last expression in an expression
11028                          * statement as it has always an effect */
11029                         if (inside_expression_statement && sub_statement->base.next == NULL)
11030                                 continue;
11031
11032                         expression_t *expression = sub_statement->expression.expression;
11033                         if (!expression_has_effect(expression)) {
11034                                 warningf(&expression->base.source_position,
11035                                          "statement has no effect");
11036                         }
11037                 }
11038         }
11039
11040 end_error:
11041         rem_anchor_token(T_while);
11042         rem_anchor_token(T_wchar_t);
11043         rem_anchor_token(T_volatile);
11044         rem_anchor_token(T_void);
11045         rem_anchor_token(T_using);
11046         rem_anchor_token(T_unsigned);
11047         rem_anchor_token(T_union);
11048         rem_anchor_token(T_typeof);
11049         rem_anchor_token(T_typename);
11050         rem_anchor_token(T_typeid);
11051         rem_anchor_token(T_typedef);
11052         rem_anchor_token(T_try);
11053         rem_anchor_token(T_true);
11054         rem_anchor_token(T_throw);
11055         rem_anchor_token(T_this);
11056         rem_anchor_token(T_template);
11057         rem_anchor_token(T_switch);
11058         rem_anchor_token(T_struct);
11059         rem_anchor_token(T_static_cast);
11060         rem_anchor_token(T_static);
11061         rem_anchor_token(T_sizeof);
11062         rem_anchor_token(T_signed);
11063         rem_anchor_token(T_short);
11064         rem_anchor_token(T_return);
11065         rem_anchor_token(T_restrict);
11066         rem_anchor_token(T_reinterpret_cast);
11067         rem_anchor_token(T_register);
11068         rem_anchor_token(T_operator);
11069         rem_anchor_token(T_new);
11070         rem_anchor_token(T_long);
11071         rem_anchor_token(T_int);
11072         rem_anchor_token(T_inline);
11073         rem_anchor_token(T_if);
11074         rem_anchor_token(T_goto);
11075         rem_anchor_token(T_for);
11076         rem_anchor_token(T_float);
11077         rem_anchor_token(T_false);
11078         rem_anchor_token(T_extern);
11079         rem_anchor_token(T_enum);
11080         rem_anchor_token(T_dynamic_cast);
11081         rem_anchor_token(T_do);
11082         rem_anchor_token(T_double);
11083         rem_anchor_token(T_delete);
11084         rem_anchor_token(T_default);
11085         rem_anchor_token(T_continue);
11086         rem_anchor_token(T_const_cast);
11087         rem_anchor_token(T_const);
11088         rem_anchor_token(T_class);
11089         rem_anchor_token(T_char);
11090         rem_anchor_token(T_case);
11091         rem_anchor_token(T_break);
11092         rem_anchor_token(T_bool);
11093         rem_anchor_token(T_auto);
11094         rem_anchor_token(T_asm);
11095         rem_anchor_token(T___thread);
11096         rem_anchor_token(T___real__);
11097         rem_anchor_token(T___label__);
11098         rem_anchor_token(T___imag__);
11099         rem_anchor_token(T___func__);
11100         rem_anchor_token(T___extension__);
11101         rem_anchor_token(T___builtin_va_start);
11102         rem_anchor_token(T___attribute__);
11103         rem_anchor_token(T___alignof__);
11104         rem_anchor_token(T___PRETTY_FUNCTION__);
11105         rem_anchor_token(T___FUNCTION__);
11106         rem_anchor_token(T__Imaginary);
11107         rem_anchor_token(T__Complex);
11108         rem_anchor_token(T__Bool);
11109         rem_anchor_token(T_WIDE_STRING_LITERAL);
11110         rem_anchor_token(T_WIDE_CHARACTER_CONSTANT);
11111         rem_anchor_token(T_STRING_LITERAL);
11112         rem_anchor_token(T_PLUSPLUS);
11113         rem_anchor_token(T_MINUSMINUS);
11114         rem_anchor_token(T_INTEGER);
11115         rem_anchor_token(T_IDENTIFIER);
11116         rem_anchor_token(T_FLOATINGPOINT);
11117         rem_anchor_token(T_COLONCOLON);
11118         rem_anchor_token(T_CHARACTER_CONSTANT);
11119         rem_anchor_token('~');
11120         rem_anchor_token('{');
11121         rem_anchor_token('-');
11122         rem_anchor_token('+');
11123         rem_anchor_token('*');
11124         rem_anchor_token('(');
11125         rem_anchor_token('&');
11126         rem_anchor_token('!');
11127         rem_anchor_token('}');
11128         assert(current_scope == &statement->compound.scope);
11129         scope_pop(old_scope);
11130         environment_pop_to(top);
11131
11132         POP_PARENT;
11133         return statement;
11134 }
11135
11136 /**
11137  * Check for unused global static functions and variables
11138  */
11139 static void check_unused_globals(void)
11140 {
11141         if (!warning.unused_function && !warning.unused_variable)
11142                 return;
11143
11144         for (const entity_t *entity = file_scope->entities; entity != NULL;
11145              entity = entity->base.next) {
11146                 if (!is_declaration(entity))
11147                         continue;
11148
11149                 const declaration_t *declaration = &entity->declaration;
11150                 if (declaration->used                  ||
11151                     declaration->modifiers & DM_UNUSED ||
11152                     declaration->modifiers & DM_USED   ||
11153                     declaration->storage_class != STORAGE_CLASS_STATIC)
11154                         continue;
11155
11156                 type_t *const type = declaration->type;
11157                 const char *s;
11158                 if (entity->kind == ENTITY_FUNCTION) {
11159                         /* inhibit warning for static inline functions */
11160                         if (entity->function.is_inline)
11161                                 continue;
11162
11163                         s = entity->function.statement != NULL ? "defined" : "declared";
11164                 } else {
11165                         s = "defined";
11166                 }
11167
11168                 warningf(&declaration->base.source_position, "'%#T' %s but not used",
11169                         type, declaration->base.symbol, s);
11170         }
11171 }
11172
11173 static void parse_global_asm(void)
11174 {
11175         statement_t *statement = allocate_statement_zero(STATEMENT_ASM);
11176
11177         eat(T_asm);
11178         expect('(', end_error);
11179
11180         statement->asms.asm_text = parse_string_literals();
11181         statement->base.next     = unit->global_asm;
11182         unit->global_asm         = statement;
11183
11184         expect(')', end_error);
11185         expect(';', end_error);
11186
11187 end_error:;
11188 }
11189
11190 static void parse_linkage_specification(void)
11191 {
11192         eat(T_extern);
11193         assert(token.type == T_STRING_LITERAL);
11194
11195         const char *linkage = parse_string_literals().begin;
11196
11197         linkage_kind_t old_linkage = current_linkage;
11198         linkage_kind_t new_linkage;
11199         if (strcmp(linkage, "C") == 0) {
11200                 new_linkage = LINKAGE_C;
11201         } else if (strcmp(linkage, "C++") == 0) {
11202                 new_linkage = LINKAGE_CXX;
11203         } else {
11204                 errorf(HERE, "linkage string \"%s\" not recognized", linkage);
11205                 new_linkage = LINKAGE_INVALID;
11206         }
11207         current_linkage = new_linkage;
11208
11209         if (token.type == '{') {
11210                 next_token();
11211                 parse_externals();
11212                 expect('}', end_error);
11213         } else {
11214                 parse_external();
11215         }
11216
11217 end_error:
11218         assert(current_linkage == new_linkage);
11219         current_linkage = old_linkage;
11220 }
11221
11222 static void parse_external(void)
11223 {
11224         switch (token.type) {
11225                 DECLARATION_START_NO_EXTERN
11226                 case T_IDENTIFIER:
11227                 case T___extension__:
11228                 /* tokens below are for implicit int */
11229                 case '&': /* & x; -> int& x; (and error later, because C++ has no
11230                              implicit int) */
11231                 case '*': /* * x; -> int* x; */
11232                 case '(': /* (x); -> int (x); */
11233                         parse_external_declaration();
11234                         return;
11235
11236                 case T_extern:
11237                         if (look_ahead(1)->type == T_STRING_LITERAL) {
11238                                 parse_linkage_specification();
11239                         } else {
11240                                 parse_external_declaration();
11241                         }
11242                         return;
11243
11244                 case T_asm:
11245                         parse_global_asm();
11246                         return;
11247
11248                 case T_namespace:
11249                         parse_namespace_definition();
11250                         return;
11251
11252                 case ';':
11253                         if (!strict_mode) {
11254                                 if (warning.other)
11255                                         warningf(HERE, "stray ';' outside of function");
11256                                 next_token();
11257                                 return;
11258                         }
11259                         /* FALLTHROUGH */
11260
11261                 default:
11262                         errorf(HERE, "stray %K outside of function", &token);
11263                         if (token.type == '(' || token.type == '{' || token.type == '[')
11264                                 eat_until_matching_token(token.type);
11265                         next_token();
11266                         return;
11267         }
11268 }
11269
11270 static void parse_externals(void)
11271 {
11272         add_anchor_token('}');
11273         add_anchor_token(T_EOF);
11274
11275 #ifndef NDEBUG
11276         unsigned char token_anchor_copy[T_LAST_TOKEN];
11277         memcpy(token_anchor_copy, token_anchor_set, sizeof(token_anchor_copy));
11278 #endif
11279
11280         while (token.type != T_EOF && token.type != '}') {
11281 #ifndef NDEBUG
11282                 bool anchor_leak = false;
11283                 for (int i = 0; i != T_LAST_TOKEN; ++i) {
11284                         unsigned char count = token_anchor_set[i] - token_anchor_copy[i];
11285                         if (count != 0) {
11286                                 errorf(HERE, "Leaked anchor token %k %d times", i, count);
11287                                 anchor_leak = true;
11288                         }
11289                 }
11290                 if (in_gcc_extension) {
11291                         errorf(HERE, "Leaked __extension__");
11292                         anchor_leak = true;
11293                 }
11294
11295                 if (anchor_leak)
11296                         abort();
11297 #endif
11298
11299                 parse_external();
11300         }
11301
11302         rem_anchor_token(T_EOF);
11303         rem_anchor_token('}');
11304 }
11305
11306 /**
11307  * Parse a translation unit.
11308  */
11309 static void parse_translation_unit(void)
11310 {
11311         add_anchor_token(T_EOF);
11312
11313         while (true) {
11314                 parse_externals();
11315
11316                 if (token.type == T_EOF)
11317                         break;
11318
11319                 errorf(HERE, "stray %K outside of function", &token);
11320                 if (token.type == '(' || token.type == '{' || token.type == '[')
11321                         eat_until_matching_token(token.type);
11322                 next_token();
11323         }
11324 }
11325
11326 /**
11327  * Parse the input.
11328  *
11329  * @return  the translation unit or NULL if errors occurred.
11330  */
11331 void start_parsing(void)
11332 {
11333         environment_stack = NEW_ARR_F(stack_entry_t, 0);
11334         label_stack       = NEW_ARR_F(stack_entry_t, 0);
11335         diagnostic_count  = 0;
11336         error_count       = 0;
11337         warning_count     = 0;
11338
11339         type_set_output(stderr);
11340         ast_set_output(stderr);
11341
11342         assert(unit == NULL);
11343         unit = allocate_ast_zero(sizeof(unit[0]));
11344
11345         assert(file_scope == NULL);
11346         file_scope = &unit->scope;
11347
11348         assert(current_scope == NULL);
11349         scope_push(&unit->scope);
11350 }
11351
11352 translation_unit_t *finish_parsing(void)
11353 {
11354         assert(current_scope == &unit->scope);
11355         scope_pop(NULL);
11356
11357         assert(file_scope == &unit->scope);
11358         check_unused_globals();
11359         file_scope = NULL;
11360
11361         DEL_ARR_F(environment_stack);
11362         DEL_ARR_F(label_stack);
11363
11364         translation_unit_t *result = unit;
11365         unit = NULL;
11366         return result;
11367 }
11368
11369 /* GCC allows global arrays without size and assigns them a length of one,
11370  * if no different declaration follows */
11371 static void complete_incomplete_arrays(void)
11372 {
11373         size_t n = ARR_LEN(incomplete_arrays);
11374         for (size_t i = 0; i != n; ++i) {
11375                 declaration_t *const decl      = incomplete_arrays[i];
11376                 type_t        *const orig_type = decl->type;
11377                 type_t        *const type      = skip_typeref(orig_type);
11378
11379                 if (!is_type_incomplete(type))
11380                         continue;
11381
11382                 if (warning.other) {
11383                         warningf(&decl->base.source_position,
11384                                         "array '%#T' assumed to have one element",
11385                                         orig_type, decl->base.symbol);
11386                 }
11387
11388                 type_t *const new_type = duplicate_type(type);
11389                 new_type->array.size_constant     = true;
11390                 new_type->array.has_implicit_size = true;
11391                 new_type->array.size              = 1;
11392
11393                 type_t *const result = identify_new_type(new_type);
11394
11395                 decl->type = result;
11396         }
11397 }
11398
11399 void parse(void)
11400 {
11401         lookahead_bufpos = 0;
11402         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
11403                 next_token();
11404         }
11405         current_linkage   = c_mode & _CXX ? LINKAGE_CXX : LINKAGE_C;
11406         incomplete_arrays = NEW_ARR_F(declaration_t*, 0);
11407         parse_translation_unit();
11408         complete_incomplete_arrays();
11409         DEL_ARR_F(incomplete_arrays);
11410         incomplete_arrays = NULL;
11411 }
11412
11413 /**
11414  * Initialize the parser.
11415  */
11416 void init_parser(void)
11417 {
11418         sym_anonymous = symbol_table_insert("<anonymous>");
11419
11420         if (c_mode & _MS) {
11421                 /* add predefined symbols for extended-decl-modifier */
11422                 sym_align         = symbol_table_insert("align");
11423                 sym_allocate      = symbol_table_insert("allocate");
11424                 sym_dllimport     = symbol_table_insert("dllimport");
11425                 sym_dllexport     = symbol_table_insert("dllexport");
11426                 sym_naked         = symbol_table_insert("naked");
11427                 sym_noinline      = symbol_table_insert("noinline");
11428                 sym_returns_twice = symbol_table_insert("returns_twice");
11429                 sym_noreturn      = symbol_table_insert("noreturn");
11430                 sym_nothrow       = symbol_table_insert("nothrow");
11431                 sym_novtable      = symbol_table_insert("novtable");
11432                 sym_property      = symbol_table_insert("property");
11433                 sym_get           = symbol_table_insert("get");
11434                 sym_put           = symbol_table_insert("put");
11435                 sym_selectany     = symbol_table_insert("selectany");
11436                 sym_thread        = symbol_table_insert("thread");
11437                 sym_uuid          = symbol_table_insert("uuid");
11438                 sym_deprecated    = symbol_table_insert("deprecated");
11439                 sym_restrict      = symbol_table_insert("restrict");
11440                 sym_noalias       = symbol_table_insert("noalias");
11441         }
11442         memset(token_anchor_set, 0, sizeof(token_anchor_set));
11443
11444         init_expression_parsers();
11445         obstack_init(&temp_obst);
11446
11447         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
11448         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
11449 }
11450
11451 /**
11452  * Terminate the parser.
11453  */
11454 void exit_parser(void)
11455 {
11456         obstack_free(&temp_obst, NULL);
11457 }