nsz Git - cparser/blob - parser.c

   1 /*
   2  * This file is part of cparser.
   3  * Copyright (C) 2007-2008 Matthias Braun <matze@braunis.de>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  18  * 02111-1307, USA.
  19  */
  20 #include <config.h>
  21
  22 #include <assert.h>
  23 #include <stdarg.h>
  24 #include <stdbool.h>
  25
  26 #include "parser.h"
  27 #include "diagnostic.h"
  28 #include "format_check.h"
  29 #include "lexer.h"
  30 #include "symbol_t.h"
  31 #include "token_t.h"
  32 #include "types.h"
  33 #include "type_t.h"
  34 #include "type_hash.h"
  35 #include "ast_t.h"
  36 #include "entity_t.h"
  37 #include "lang_features.h"
  38 #include "walk_statements.h"
  39 #include "warning.h"
  40 #include "adt/bitfiddle.h"
  41 #include "adt/error.h"
  42 #include "adt/array.h"
  43
  44 //#define PRINT_TOKENS
  45 #define MAX_LOOKAHEAD 2
  46
  47 typedef struct {
  48         entity_t           *old_entity;
  49         symbol_t           *symbol;
  50         entity_namespace_t  namespc;
  51 } stack_entry_t;
  52
  53 typedef struct argument_list_t argument_list_t;
  54 struct argument_list_t {
  55         long              argument;
  56         argument_list_t  *next;
  57 };
  58
  59 typedef struct gnu_attribute_t gnu_attribute_t;
  60 struct gnu_attribute_t {
  61         gnu_attribute_kind_t kind;           /**< The kind of the GNU attribute. */
  62         gnu_attribute_t     *next;
  63         bool                 invalid;        /**< Set if this attribute had argument errors, */
  64         bool                 have_arguments; /**< True, if this attribute has arguments. */
  65         union {
  66                 size_t              value;
  67                 string_t            string;
  68                 atomic_type_kind_t  akind;
  69                 long                argument;  /**< Single argument. */
  70                 argument_list_t    *arguments; /**< List of argument expressions. */
  71         } u;
  72 };
  73
  74 typedef struct declaration_specifiers_t  declaration_specifiers_t;
  75 struct declaration_specifiers_t {
  76         source_position_t  source_position;
  77         storage_class_t    storage_class;
  78         unsigned char      alignment;         /**< Alignment, 0 if not set. */
  79         bool               is_inline    : 1;
  80         bool               thread_local : 1;  /**< GCC __thread */
  81         bool               deprecated   : 1;
  82         decl_modifiers_t   modifiers;         /**< declaration modifiers */
  83         gnu_attribute_t   *gnu_attributes;    /**< list of GNU attributes */
  84         const char        *deprecated_string; /**< can be set if declaration was marked deprecated. */
  85         symbol_t          *get_property_sym;  /**< the name of the get property if set. */
  86         symbol_t          *put_property_sym;  /**< the name of the put property if set. */
  87         type_t            *type;
  88 };
  89
  90 /**
  91  * An environment for parsing initializers (and compound literals).
  92  */
  93 typedef struct parse_initializer_env_t {
  94         type_t     *type;   /**< the type of the initializer. In case of an
  95                                  array type with unspecified size this gets
  96                                  adjusted to the actual size. */
  97         entity_t   *entity; /**< the variable that is initialized if any */
  98         bool        must_be_constant;
  99 } parse_initializer_env_t;
 100
 101 /**
 102  * Capture a MS __base extension.
 103  */
 104 typedef struct based_spec_t {
 105         source_position_t  source_position;
 106         variable_t        *base_variable;
 107 } based_spec_t;
 108
 109 typedef entity_t* (*parsed_declaration_func) (entity_t *declaration, bool is_definition);
 110
 111 /** The current token. */
 112 static token_t              token;
 113 /** The lookahead ring-buffer. */
 114 static token_t              lookahead_buffer[MAX_LOOKAHEAD];
 115 /** Position of the next token in the lookahead buffer. */
 116 static int                  lookahead_bufpos;
 117 static stack_entry_t       *environment_stack = NULL;
 118 static stack_entry_t       *label_stack       = NULL;
 119 static scope_t             *file_scope        = NULL;
 120 static scope_t             *current_scope     = NULL;
 121 /** Point to the current function declaration if inside a function. */
 122 static function_t          *current_function  = NULL;
 123 static entity_t            *current_init_decl = NULL;
 124 static switch_statement_t  *current_switch    = NULL;
 125 static statement_t         *current_loop      = NULL;
 126 static statement_t         *current_parent    = NULL;
 127 static ms_try_statement_t  *current_try       = NULL;
 128 static linkage_kind_t       current_linkage   = LINKAGE_INVALID;
 129 static goto_statement_t    *goto_first        = NULL;
 130 static goto_statement_t   **goto_anchor       = NULL;
 131 static label_statement_t   *label_first       = NULL;
 132 static label_statement_t  **label_anchor      = NULL;
 133 /** current translation unit. */
 134 static translation_unit_t  *unit              = NULL;
 135 /** true if we are in a type property context (evaluation only for type. */
 136 static bool                 in_type_prop      = false;
 137 /** true in we are in a __extension__ context. */
 138 static bool                 in_gcc_extension  = false;
 139 static struct obstack       temp_obst;
 140 static entity_t            *anonymous_entity;
 141 static declaration_t      **incomplete_arrays;
 142
 143
 144 #define PUSH_PARENT(stmt)                          \
 145         statement_t *const prev_parent = current_parent; \
 146         ((void)(current_parent = (stmt)))
 147 #define POP_PARENT ((void)(current_parent = prev_parent))
 148
 149 /** special symbol used for anonymous entities. */
 150 static const symbol_t *sym_anonymous = NULL;
 151
 152 /* symbols for Microsoft extended-decl-modifier */
 153 static const symbol_t *sym_align      = NULL;
 154 static const symbol_t *sym_allocate   = NULL;
 155 static const symbol_t *sym_dllimport  = NULL;
 156 static const symbol_t *sym_dllexport  = NULL;
 157 static const symbol_t *sym_naked      = NULL;
 158 static const symbol_t *sym_noinline   = NULL;
 159 static const symbol_t *sym_noreturn   = NULL;
 160 static const symbol_t *sym_nothrow    = NULL;
 161 static const symbol_t *sym_novtable   = NULL;
 162 static const symbol_t *sym_property   = NULL;
 163 static const symbol_t *sym_get        = NULL;
 164 static const symbol_t *sym_put        = NULL;
 165 static const symbol_t *sym_selectany  = NULL;
 166 static const symbol_t *sym_thread     = NULL;
 167 static const symbol_t *sym_uuid       = NULL;
 168 static const symbol_t *sym_deprecated = NULL;
 169 static const symbol_t *sym_restrict   = NULL;
 170 static const symbol_t *sym_noalias    = NULL;
 171
 172 /** The token anchor set */
 173 static unsigned char token_anchor_set[T_LAST_TOKEN];
 174
 175 /** The current source position. */
 176 #define HERE (&token.source_position)
 177
 178 /** true if we are in GCC mode. */
 179 #define GNU_MODE ((c_mode & _GNUC) || in_gcc_extension)
 180
 181 static type_t *type_valist;
 182
 183 static statement_t *parse_compound_statement(bool inside_expression_statement);
 184 static statement_t *parse_statement(void);
 185
 186 static expression_t *parse_sub_expression(precedence_t);
 187 static expression_t *parse_expression(void);
 188 static type_t       *parse_typename(void);
 189 static void          parse_externals(void);
 190 static void          parse_external(void);
 191
 192 static void parse_compound_type_entries(compound_t *compound_declaration);
 193
 194 typedef enum declarator_flags_t {
 195         DECL_FLAGS_NONE             = 0,
 196         DECL_MAY_BE_ABSTRACT        = 1U << 0,
 197         DECL_CREATE_COMPOUND_MEMBER = 1U << 1,
 198         DECL_IS_PARAMETER           = 1U << 2
 199 } declarator_flags_t;
 200
 201 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
 202                                   declarator_flags_t flags);
 203
 204 static entity_t *record_entity(entity_t *entity, bool is_definition);
 205
 206 static void semantic_comparison(binary_expression_t *expression);
 207
 208 #define STORAGE_CLASSES       \
 209         STORAGE_CLASSES_NO_EXTERN \
 210         case T_extern:
 211
 212 #define STORAGE_CLASSES_NO_EXTERN \
 213         case T_typedef:         \
 214         case T_static:          \
 215         case T_auto:            \
 216         case T_register:        \
 217         case T___thread:
 218
 219 #define TYPE_QUALIFIERS     \
 220         case T_const:           \
 221         case T_restrict:        \
 222         case T_volatile:        \
 223         case T_inline:          \
 224         case T__forceinline:    \
 225         case T___attribute__:
 226
 227 #define COMPLEX_SPECIFIERS  \
 228         case T__Complex:
 229 #define IMAGINARY_SPECIFIERS \
 230         case T__Imaginary:
 231
 232 #define TYPE_SPECIFIERS       \
 233         case T__Bool:             \
 234         case T___builtin_va_list: \
 235         case T___typeof__:        \
 236         case T__declspec:         \
 237         case T_bool:              \
 238         case T_char:              \
 239         case T_double:            \
 240         case T_enum:              \
 241         case T_float:             \
 242         case T_int:               \
 243         case T_long:              \
 244         case T_short:             \
 245         case T_signed:            \
 246         case T_struct:            \
 247         case T_union:             \
 248         case T_unsigned:          \
 249         case T_void:              \
 250         COMPLEX_SPECIFIERS        \
 251         IMAGINARY_SPECIFIERS
 252
 253 #define DECLARATION_START   \
 254         STORAGE_CLASSES         \
 255         TYPE_QUALIFIERS         \
 256         TYPE_SPECIFIERS
 257
 258 #define DECLARATION_START_NO_EXTERN \
 259         STORAGE_CLASSES_NO_EXTERN       \
 260         TYPE_QUALIFIERS                 \
 261         TYPE_SPECIFIERS
 262
 263 #define TYPENAME_START      \
 264         TYPE_QUALIFIERS         \
 265         TYPE_SPECIFIERS
 266
 267 #define EXPRESSION_START           \
 268         case '!':                        \
 269         case '&':                        \
 270         case '(':                        \
 271         case '*':                        \
 272         case '+':                        \
 273         case '-':                        \
 274         case '~':                        \
 275         case T_ANDAND:                   \
 276         case T_CHARACTER_CONSTANT:       \
 277         case T_FLOATINGPOINT:            \
 278         case T_INTEGER:                  \
 279         case T_MINUSMINUS:               \
 280         case T_PLUSPLUS:                 \
 281         case T_STRING_LITERAL:           \
 282         case T_WIDE_CHARACTER_CONSTANT:  \
 283         case T_WIDE_STRING_LITERAL:      \
 284         case T___FUNCDNAME__:            \
 285         case T___FUNCSIG__:              \
 286         case T___FUNCTION__:             \
 287         case T___PRETTY_FUNCTION__:      \
 288         case T___alignof__:              \
 289         case T___builtin_alloca:         \
 290         case T___builtin_classify_type:  \
 291         case T___builtin_constant_p:     \
 292         case T___builtin_expect:         \
 293         case T___builtin_huge_val:       \
 294         case T___builtin_inf:            \
 295         case T___builtin_inff:           \
 296         case T___builtin_infl:           \
 297         case T___builtin_isgreater:      \
 298         case T___builtin_isgreaterequal: \
 299         case T___builtin_isless:         \
 300         case T___builtin_islessequal:    \
 301         case T___builtin_islessgreater:  \
 302         case T___builtin_isunordered:    \
 303         case T___builtin_nan:            \
 304         case T___builtin_nanf:           \
 305         case T___builtin_nanl:           \
 306         case T___builtin_offsetof:       \
 307         case T___builtin_prefetch:       \
 308         case T___builtin_va_arg:         \
 309         case T___builtin_va_end:         \
 310         case T___builtin_va_start:       \
 311         case T___func__:                 \
 312         case T___noop:                   \
 313         case T__assume:                  \
 314         case T_delete:                   \
 315         case T_false:                    \
 316         case T_sizeof:                   \
 317         case T_throw:                    \
 318         case T_true:
 319
 320 /**
 321  * Allocate an AST node with given size and
 322  * initialize all fields with zero.
 323  */
 324 static void *allocate_ast_zero(size_t size)
 325 {
 326         void *res = allocate_ast(size);
 327         memset(res, 0, size);
 328         return res;
 329 }
 330
 331 /**
 332  * Returns the size of an entity node.
 333  *
 334  * @param kind  the entity kind
 335  */
 336 static size_t get_entity_struct_size(entity_kind_t kind)
 337 {
 338         static const size_t sizes[] = {
 339                 [ENTITY_VARIABLE]        = sizeof(variable_t),
 340                 [ENTITY_PARAMETER]       = sizeof(parameter_t),
 341                 [ENTITY_COMPOUND_MEMBER] = sizeof(compound_member_t),
 342                 [ENTITY_FUNCTION]        = sizeof(function_t),
 343                 [ENTITY_TYPEDEF]         = sizeof(typedef_t),
 344                 [ENTITY_STRUCT]          = sizeof(compound_t),
 345                 [ENTITY_UNION]           = sizeof(compound_t),
 346                 [ENTITY_ENUM]            = sizeof(enum_t),
 347                 [ENTITY_ENUM_VALUE]      = sizeof(enum_value_t),
 348                 [ENTITY_LABEL]           = sizeof(label_t),
 349                 [ENTITY_LOCAL_LABEL]     = sizeof(label_t),
 350                 [ENTITY_NAMESPACE]       = sizeof(namespace_t)
 351         };
 352         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 353         assert(sizes[kind] != 0);
 354         return sizes[kind];
 355 }
 356
 357 /**
 358  * Allocate an entity of given kind and initialize all
 359  * fields with zero.
 360  */
 361 static entity_t *allocate_entity_zero(entity_kind_t kind)
 362 {
 363         size_t    size   = get_entity_struct_size(kind);
 364         entity_t *entity = allocate_ast_zero(size);
 365         entity->kind     = kind;
 366         return entity;
 367 }
 368
 369 /**
 370  * Returns the size of a statement node.
 371  *
 372  * @param kind  the statement kind
 373  */
 374 static size_t get_statement_struct_size(statement_kind_t kind)
 375 {
 376         static const size_t sizes[] = {
 377                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 378                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 379                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 380                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 381                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 382                 [STATEMENT_LOCAL_LABEL] = sizeof(local_label_statement_t),
 383                 [STATEMENT_IF]          = sizeof(if_statement_t),
 384                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 385                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 386                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 387                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 388                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 389                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 390                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 391                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 392                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 393                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 394                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 395                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 396                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 397         };
 398         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 399         assert(sizes[kind] != 0);
 400         return sizes[kind];
 401 }
 402
 403 /**
 404  * Returns the size of an expression node.
 405  *
 406  * @param kind  the expression kind
 407  */
 408 static size_t get_expression_struct_size(expression_kind_t kind)
 409 {
 410         static const size_t sizes[] = {
 411                 [EXPR_INVALID]                 = sizeof(expression_base_t),
 412                 [EXPR_REFERENCE]               = sizeof(reference_expression_t),
 413                 [EXPR_REFERENCE_ENUM_VALUE]    = sizeof(reference_expression_t),
 414                 [EXPR_CONST]                   = sizeof(const_expression_t),
 415                 [EXPR_CHARACTER_CONSTANT]      = sizeof(const_expression_t),
 416                 [EXPR_WIDE_CHARACTER_CONSTANT] = sizeof(const_expression_t),
 417                 [EXPR_STRING_LITERAL]          = sizeof(string_literal_expression_t),
 418                 [EXPR_WIDE_STRING_LITERAL]     = sizeof(wide_string_literal_expression_t),
 419                 [EXPR_COMPOUND_LITERAL]        = sizeof(compound_literal_expression_t),
 420                 [EXPR_CALL]                    = sizeof(call_expression_t),
 421                 [EXPR_UNARY_FIRST]             = sizeof(unary_expression_t),
 422                 [EXPR_BINARY_FIRST]            = sizeof(binary_expression_t),
 423                 [EXPR_CONDITIONAL]             = sizeof(conditional_expression_t),
 424                 [EXPR_SELECT]                  = sizeof(select_expression_t),
 425                 [EXPR_ARRAY_ACCESS]            = sizeof(array_access_expression_t),
 426                 [EXPR_SIZEOF]                  = sizeof(typeprop_expression_t),
 427                 [EXPR_ALIGNOF]                 = sizeof(typeprop_expression_t),
 428                 [EXPR_CLASSIFY_TYPE]           = sizeof(classify_type_expression_t),
 429                 [EXPR_FUNCNAME]                = sizeof(funcname_expression_t),
 430                 [EXPR_BUILTIN_SYMBOL]          = sizeof(builtin_symbol_expression_t),
 431                 [EXPR_BUILTIN_CONSTANT_P]      = sizeof(builtin_constant_expression_t),
 432                 [EXPR_BUILTIN_PREFETCH]        = sizeof(builtin_prefetch_expression_t),
 433                 [EXPR_OFFSETOF]                = sizeof(offsetof_expression_t),
 434                 [EXPR_VA_START]                = sizeof(va_start_expression_t),
 435                 [EXPR_VA_ARG]                  = sizeof(va_arg_expression_t),
 436                 [EXPR_STATEMENT]               = sizeof(statement_expression_t),
 437                 [EXPR_LABEL_ADDRESS]           = sizeof(label_address_expression_t),
 438         };
 439         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 440                 return sizes[EXPR_UNARY_FIRST];
 441         }
 442         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 443                 return sizes[EXPR_BINARY_FIRST];
 444         }
 445         assert(kind < sizeof(sizes) / sizeof(sizes[0]));
 446         assert(sizes[kind] != 0);
 447         return sizes[kind];
 448 }
 449
 450 /**
 451  * Allocate a statement node of given kind and initialize all
 452  * fields with zero. Sets its source position to the position
 453  * of the current token.
 454  */
 455 static statement_t *allocate_statement_zero(statement_kind_t kind)
 456 {
 457         size_t       size = get_statement_struct_size(kind);
 458         statement_t *res  = allocate_ast_zero(size);
 459
 460         res->base.kind            = kind;
 461         res->base.parent          = current_parent;
 462         res->base.source_position = token.source_position;
 463         return res;
 464 }
 465
 466 /**
 467  * Allocate an expression node of given kind and initialize all
 468  * fields with zero.
 469  */
 470 static expression_t *allocate_expression_zero(expression_kind_t kind)
 471 {
 472         size_t        size = get_expression_struct_size(kind);
 473         expression_t *res  = allocate_ast_zero(size);
 474
 475         res->base.kind            = kind;
 476         res->base.type            = type_error_type;
 477         res->base.source_position = token.source_position;
 478         return res;
 479 }
 480
 481 /**
 482  * Creates a new invalid expression at the source position
 483  * of the current token.
 484  */
 485 static expression_t *create_invalid_expression(void)
 486 {
 487         return allocate_expression_zero(EXPR_INVALID);
 488 }
 489
 490 /**
 491  * Creates a new invalid statement.
 492  */
 493 static statement_t *create_invalid_statement(void)
 494 {
 495         return allocate_statement_zero(STATEMENT_INVALID);
 496 }
 497
 498 /**
 499  * Allocate a new empty statement.
 500  */
 501 static statement_t *create_empty_statement(void)
 502 {
 503         return allocate_statement_zero(STATEMENT_EMPTY);
 504 }
 505
 506 /**
 507  * Returns the size of a type node.
 508  *
 509  * @param kind  the type kind
 510  */
 511 static size_t get_type_struct_size(type_kind_t kind)
 512 {
 513         static const size_t sizes[] = {
 514                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
 515                 [TYPE_COMPLEX]         = sizeof(complex_type_t),
 516                 [TYPE_IMAGINARY]       = sizeof(imaginary_type_t),
 517                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
 518                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
 519                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
 520                 [TYPE_ENUM]            = sizeof(enum_type_t),
 521                 [TYPE_FUNCTION]        = sizeof(function_type_t),
 522                 [TYPE_POINTER]         = sizeof(pointer_type_t),
 523                 [TYPE_ARRAY]           = sizeof(array_type_t),
 524                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
 525                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
 526                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
 527         };
 528         assert(sizeof(sizes) / sizeof(sizes[0]) == (int) TYPE_TYPEOF + 1);
 529         assert(kind <= TYPE_TYPEOF);
 530         assert(sizes[kind] != 0);
 531         return sizes[kind];
 532 }
 533
 534 /**
 535  * Allocate a type node of given kind and initialize all
 536  * fields with zero.
 537  *
 538  * @param kind             type kind to allocate
 539  */
 540 static type_t *allocate_type_zero(type_kind_t kind)
 541 {
 542         size_t  size = get_type_struct_size(kind);
 543         type_t *res  = obstack_alloc(type_obst, size);
 544         memset(res, 0, size);
 545         res->base.kind = kind;
 546
 547         return res;
 548 }
 549
 550 /**
 551  * Returns the size of an initializer node.
 552  *
 553  * @param kind  the initializer kind
 554  */
 555 static size_t get_initializer_size(initializer_kind_t kind)
 556 {
 557         static const size_t sizes[] = {
 558                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 559                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 560                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 561                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 562                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 563         };
 564         assert(kind < sizeof(sizes) / sizeof(*sizes));
 565         assert(sizes[kind] != 0);
 566         return sizes[kind];
 567 }
 568
 569 /**
 570  * Allocate an initializer node of given kind and initialize all
 571  * fields with zero.
 572  */
 573 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 574 {
 575         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 576         result->kind          = kind;
 577
 578         return result;
 579 }
 580
 581 /**
 582  * Free a type from the type obstack.
 583  */
 584 static void free_type(void *type)
 585 {
 586         obstack_free(type_obst, type);
 587 }
 588
 589 /**
 590  * Returns the index of the top element of the environment stack.
 591  */
 592 static size_t environment_top(void)
 593 {
 594         return ARR_LEN(environment_stack);
 595 }
 596
 597 /**
 598  * Returns the index of the top element of the global label stack.
 599  */
 600 static size_t label_top(void)
 601 {
 602         return ARR_LEN(label_stack);
 603 }
 604
 605 /**
 606  * Return the next token.
 607  */
 608 static inline void next_token(void)
 609 {
 610         token                              = lookahead_buffer[lookahead_bufpos];
 611         lookahead_buffer[lookahead_bufpos] = lexer_token;
 612         lexer_next_token();
 613
 614         lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
 615
 616 #ifdef PRINT_TOKENS
 617         print_token(stderr, &token);
 618         fprintf(stderr, "\n");
 619 #endif
 620 }
 621
 622 /**
 623  * Return the next token with a given lookahead.
 624  */
 625 static inline const token_t *look_ahead(int num)
 626 {
 627         assert(num > 0 && num <= MAX_LOOKAHEAD);
 628         int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
 629         return &lookahead_buffer[pos];
 630 }
 631
 632 /**
 633  * Adds a token type to the token type anchor set (a multi-set).
 634  */
 635 static void add_anchor_token(int token_type)
 636 {
 637         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 638         ++token_anchor_set[token_type];
 639 }
 640
 641 /**
 642  * Set the number of tokens types of the given type
 643  * to zero and return the old count.
 644  */
 645 static int save_and_reset_anchor_state(int token_type)
 646 {
 647         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 648         int count = token_anchor_set[token_type];
 649         token_anchor_set[token_type] = 0;
 650         return count;
 651 }
 652
 653 /**
 654  * Restore the number of token types to the given count.
 655  */
 656 static void restore_anchor_state(int token_type, int count)
 657 {
 658         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 659         token_anchor_set[token_type] = count;
 660 }
 661
 662 /**
 663  * Remove a token type from the token type anchor set (a multi-set).
 664  */
 665 static void rem_anchor_token(int token_type)
 666 {
 667         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 668         assert(token_anchor_set[token_type] != 0);
 669         --token_anchor_set[token_type];
 670 }
 671
 672 /**
 673  * Return true if the token type of the current token is
 674  * in the anchor set.
 675  */
 676 static bool at_anchor(void)
 677 {
 678         if (token.type < 0)
 679                 return false;
 680         return token_anchor_set[token.type];
 681 }
 682
 683 /**
 684  * Eat tokens until a matching token type is found.
 685  */
 686 static void eat_until_matching_token(int type)
 687 {
 688         int end_token;
 689         switch (type) {
 690                 case '(': end_token = ')';  break;
 691                 case '{': end_token = '}';  break;
 692                 case '[': end_token = ']';  break;
 693                 default:  end_token = type; break;
 694         }
 695
 696         unsigned parenthesis_count = 0;
 697         unsigned brace_count       = 0;
 698         unsigned bracket_count     = 0;
 699         while (token.type        != end_token ||
 700                parenthesis_count != 0         ||
 701                brace_count       != 0         ||
 702                bracket_count     != 0) {
 703                 switch (token.type) {
 704                 case T_EOF: return;
 705                 case '(': ++parenthesis_count; break;
 706                 case '{': ++brace_count;       break;
 707                 case '[': ++bracket_count;     break;
 708
 709                 case ')':
 710                         if (parenthesis_count > 0)
 711                                 --parenthesis_count;
 712                         goto check_stop;
 713
 714                 case '}':
 715                         if (brace_count > 0)
 716                                 --brace_count;
 717                         goto check_stop;
 718
 719                 case ']':
 720                         if (bracket_count > 0)
 721                                 --bracket_count;
 722 check_stop:
 723                         if (token.type        == end_token &&
 724                             parenthesis_count == 0         &&
 725                             brace_count       == 0         &&
 726                             bracket_count     == 0)
 727                                 return;
 728                         break;
 729
 730                 default:
 731                         break;
 732                 }
 733                 next_token();
 734         }
 735 }
 736
 737 /**
 738  * Eat input tokens until an anchor is found.
 739  */
 740 static void eat_until_anchor(void)
 741 {
 742         while (token_anchor_set[token.type] == 0) {
 743                 if (token.type == '(' || token.type == '{' || token.type == '[')
 744                         eat_until_matching_token(token.type);
 745                 next_token();
 746         }
 747 }
 748
 749 /**
 750  * Eat a whole block from input tokens.
 751  */
 752 static void eat_block(void)
 753 {
 754         eat_until_matching_token('{');
 755         if (token.type == '}')
 756                 next_token();
 757 }
 758
 759 #define eat(token_type)  do { assert(token.type == (token_type)); next_token(); } while (0)
 760
 761 /**
 762  * Report a parse error because an expected token was not found.
 763  */
 764 static
 765 #if defined __GNUC__ && __GNUC__ >= 4
 766 __attribute__((sentinel))
 767 #endif
 768 void parse_error_expected(const char *message, ...)
 769 {
 770         if (message != NULL) {
 771                 errorf(HERE, "%s", message);
 772         }
 773         va_list ap;
 774         va_start(ap, message);
 775         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 776         va_end(ap);
 777 }
 778
 779 /**
 780  * Report an incompatible type.
 781  */
 782 static void type_error_incompatible(const char *msg,
 783                 const source_position_t *source_position, type_t *type1, type_t *type2)
 784 {
 785         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 786                msg, type1, type2);
 787 }
 788
 789 /**
 790  * Expect the current token is the expected token.
 791  * If not, generate an error, eat the current statement,
 792  * and goto the end_error label.
 793  */
 794 #define expect(expected, error_label)                     \
 795         do {                                                  \
 796                 if (UNLIKELY(token.type != (expected))) {         \
 797                         parse_error_expected(NULL, (expected), NULL); \
 798                         add_anchor_token(expected);                   \
 799                         eat_until_anchor();                           \
 800                         if (token.type == expected)                   \
 801                                 next_token();                             \
 802                         rem_anchor_token(expected);                   \
 803                         goto error_label;                             \
 804                 }                                                 \
 805                 next_token();                                     \
 806         } while (0)
 807
 808 /**
 809  * Push a given scope on the scope stack and make it the
 810  * current scope
 811  */
 812 static scope_t *scope_push(scope_t *new_scope)
 813 {
 814         if (current_scope != NULL) {
 815                 new_scope->depth = current_scope->depth + 1;
 816         }
 817
 818         scope_t *old_scope = current_scope;
 819         current_scope      = new_scope;
 820         return old_scope;
 821 }
 822
 823 /**
 824  * Pop the current scope from the scope stack.
 825  */
 826 static void scope_pop(scope_t *old_scope)
 827 {
 828         current_scope = old_scope;
 829 }
 830
 831 /**
 832  * Search an entity by its symbol in a given namespace.
 833  */
 834 static entity_t *get_entity(const symbol_t *const symbol,
 835                             namespace_tag_t namespc)
 836 {
 837         entity_t *entity = symbol->entity;
 838         for (; entity != NULL; entity = entity->base.symbol_next) {
 839                 if (entity->base.namespc == namespc)
 840                         return entity;
 841         }
 842
 843         return NULL;
 844 }
 845
 846 /**
 847  * pushs an entity on the environment stack and links the corresponding symbol
 848  * it.
 849  */
 850 static void stack_push(stack_entry_t **stack_ptr, entity_t *entity)
 851 {
 852         symbol_t           *symbol  = entity->base.symbol;
 853         entity_namespace_t  namespc = entity->base.namespc;
 854         assert(namespc != NAMESPACE_INVALID);
 855
 856         /* replace/add entity into entity list of the symbol */
 857         entity_t **anchor;
 858         entity_t  *iter;
 859         for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 860                 iter = *anchor;
 861                 if (iter == NULL)
 862                         break;
 863
 864                 /* replace an entry? */
 865                 if (iter->base.namespc == namespc) {
 866                         entity->base.symbol_next = iter->base.symbol_next;
 867                         break;
 868                 }
 869         }
 870         *anchor = entity;
 871
 872         /* remember old declaration */
 873         stack_entry_t entry;
 874         entry.symbol     = symbol;
 875         entry.old_entity = iter;
 876         entry.namespc    = namespc;
 877         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 878 }
 879
 880 /**
 881  * Push an entity on the environment stack.
 882  */
 883 static void environment_push(entity_t *entity)
 884 {
 885         assert(entity->base.source_position.input_name != NULL);
 886         assert(entity->base.parent_scope != NULL);
 887         stack_push(&environment_stack, entity);
 888 }
 889
 890 /**
 891  * Push a declaration on the global label stack.
 892  *
 893  * @param declaration  the declaration
 894  */
 895 static void label_push(entity_t *label)
 896 {
 897         /* we abuse the parameters scope as parent for the labels */
 898         label->base.parent_scope = &current_function->parameters;
 899         stack_push(&label_stack, label);
 900 }
 901
 902 /**
 903  * pops symbols from the environment stack until @p new_top is the top element
 904  */
 905 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 906 {
 907         stack_entry_t *stack = *stack_ptr;
 908         size_t         top   = ARR_LEN(stack);
 909         size_t         i;
 910
 911         assert(new_top <= top);
 912         if (new_top == top)
 913                 return;
 914
 915         for (i = top; i > new_top; --i) {
 916                 stack_entry_t *entry = &stack[i - 1];
 917
 918                 entity_t           *old_entity = entry->old_entity;
 919                 symbol_t           *symbol     = entry->symbol;
 920                 entity_namespace_t  namespc    = entry->namespc;
 921
 922                 /* replace with old_entity/remove */
 923                 entity_t **anchor;
 924                 entity_t  *iter;
 925                 for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 926                         iter = *anchor;
 927                         assert(iter != NULL);
 928                         /* replace an entry? */
 929                         if (iter->base.namespc == namespc)
 930                                 break;
 931                 }
 932
 933                 /* restore definition from outer scopes (if there was one) */
 934                 if (old_entity != NULL) {
 935                         old_entity->base.symbol_next = iter->base.symbol_next;
 936                         *anchor                      = old_entity;
 937                 } else {
 938                         /* remove entry from list */
 939                         *anchor = iter->base.symbol_next;
 940                 }
 941         }
 942
 943         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
 944 }
 945
 946 /**
 947  * Pop all entries from the environment stack until the new_top
 948  * is reached.
 949  *
 950  * @param new_top  the new stack top
 951  */
 952 static void environment_pop_to(size_t new_top)
 953 {
 954         stack_pop_to(&environment_stack, new_top);
 955 }
 956
 957 /**
 958  * Pop all entries from the global label stack until the new_top
 959  * is reached.
 960  *
 961  * @param new_top  the new stack top
 962  */
 963 static void label_pop_to(size_t new_top)
 964 {
 965         stack_pop_to(&label_stack, new_top);
 966 }
 967
 968 static int get_akind_rank(atomic_type_kind_t akind)
 969 {
 970         return (int) akind;
 971 }
 972
 973 /**
 974  * Return the type rank for an atomic type.
 975  */
 976 static int get_rank(const type_t *type)
 977 {
 978         assert(!is_typeref(type));
 979         /* The C-standard allows promoting enums to int or unsigned int (see § 7.2.2
 980          * and esp. footnote 108). However we can't fold constants (yet), so we
 981          * can't decide whether unsigned int is possible, while int always works.
 982          * (unsigned int would be preferable when possible... for stuff like
 983          *  struct { enum { ... } bla : 4; } ) */
 984         if (type->kind == TYPE_ENUM)
 985                 return get_akind_rank(ATOMIC_TYPE_INT);
 986
 987         assert(type->kind == TYPE_ATOMIC);
 988         return get_akind_rank(type->atomic.akind);
 989 }
 990
 991 /**
 992  * Do integer promotion for a given type.
 993  *
 994  * @param type  the type to promote
 995  * @return the promoted type
 996  */
 997 static type_t *promote_integer(type_t *type)
 998 {
 999         if (type->kind == TYPE_BITFIELD)
1000                 type = type->bitfield.base_type;
1001
1002         if (get_rank(type) < get_akind_rank(ATOMIC_TYPE_INT))
1003                 type = type_int;
1004
1005         return type;
1006 }
1007
1008 /**
1009  * Create a cast expression.
1010  *
1011  * @param expression  the expression to cast
1012  * @param dest_type   the destination type
1013  */
1014 static expression_t *create_cast_expression(expression_t *expression,
1015                                             type_t *dest_type)
1016 {
1017         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
1018
1019         cast->unary.value = expression;
1020         cast->base.type   = dest_type;
1021
1022         return cast;
1023 }
1024
1025 /**
1026  * Check if a given expression represents a null pointer constant.
1027  *
1028  * @param expression  the expression to check
1029  */
1030 static bool is_null_pointer_constant(const expression_t *expression)
1031 {
1032         /* skip void* cast */
1033         if (expression->kind == EXPR_UNARY_CAST
1034                         || expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
1035                 expression = expression->unary.value;
1036         }
1037
1038         /* TODO: not correct yet, should be any constant integer expression
1039          * which evaluates to 0 */
1040         if (expression->kind != EXPR_CONST)
1041                 return false;
1042
1043         type_t *const type = skip_typeref(expression->base.type);
1044         if (!is_type_integer(type))
1045                 return false;
1046
1047         return expression->conste.v.int_value == 0;
1048 }
1049
1050 /**
1051  * Create an implicit cast expression.
1052  *
1053  * @param expression  the expression to cast
1054  * @param dest_type   the destination type
1055  */
1056 static expression_t *create_implicit_cast(expression_t *expression,
1057                                           type_t *dest_type)
1058 {
1059         type_t *const source_type = expression->base.type;
1060
1061         if (source_type == dest_type)
1062                 return expression;
1063
1064         return create_cast_expression(expression, dest_type);
1065 }
1066
1067 typedef enum assign_error_t {
1068         ASSIGN_SUCCESS,
1069         ASSIGN_ERROR_INCOMPATIBLE,
1070         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
1071         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
1072         ASSIGN_WARNING_POINTER_FROM_INT,
1073         ASSIGN_WARNING_INT_FROM_POINTER
1074 } assign_error_t;
1075
1076 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
1077                                 const expression_t *const right,
1078                                 const char *context,
1079                                 const source_position_t *source_position)
1080 {
1081         type_t *const orig_type_right = right->base.type;
1082         type_t *const type_left       = skip_typeref(orig_type_left);
1083         type_t *const type_right      = skip_typeref(orig_type_right);
1084
1085         switch (error) {
1086         case ASSIGN_SUCCESS:
1087                 return;
1088         case ASSIGN_ERROR_INCOMPATIBLE:
1089                 errorf(source_position,
1090                        "destination type '%T' in %s is incompatible with type '%T'",
1091                        orig_type_left, context, orig_type_right);
1092                 return;
1093
1094         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
1095                 if (warning.other) {
1096                         type_t *points_to_left  = skip_typeref(type_left->pointer.points_to);
1097                         type_t *points_to_right = skip_typeref(type_right->pointer.points_to);
1098
1099                         /* the left type has all qualifiers from the right type */
1100                         unsigned missing_qualifiers
1101                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1102                         warningf(source_position,
1103                                         "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
1104                                         orig_type_left, context, orig_type_right, missing_qualifiers);
1105                 }
1106                 return;
1107         }
1108
1109         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
1110                 if (warning.other) {
1111                         warningf(source_position,
1112                                         "destination type '%T' in %s is incompatible with '%E' of type '%T'",
1113                                         orig_type_left, context, right, orig_type_right);
1114                 }
1115                 return;
1116
1117         case ASSIGN_WARNING_POINTER_FROM_INT:
1118                 if (warning.other) {
1119                         warningf(source_position,
1120                                         "%s makes pointer '%T' from integer '%T' without a cast",
1121                                         context, orig_type_left, orig_type_right);
1122                 }
1123                 return;
1124
1125         case ASSIGN_WARNING_INT_FROM_POINTER:
1126                 if (warning.other) {
1127                         warningf(source_position,
1128                                         "%s makes integer '%T' from pointer '%T' without a cast",
1129                                         context, orig_type_left, orig_type_right);
1130                 }
1131                 return;
1132
1133         default:
1134                 panic("invalid error value");
1135         }
1136 }
1137
1138 /** Implements the rules from § 6.5.16.1 */
1139 static assign_error_t semantic_assign(type_t *orig_type_left,
1140                                       const expression_t *const right)
1141 {
1142         type_t *const orig_type_right = right->base.type;
1143         type_t *const type_left       = skip_typeref(orig_type_left);
1144         type_t *const type_right      = skip_typeref(orig_type_right);
1145
1146         if (is_type_pointer(type_left)) {
1147                 if (is_null_pointer_constant(right)) {
1148                         return ASSIGN_SUCCESS;
1149                 } else if (is_type_pointer(type_right)) {
1150                         type_t *points_to_left
1151                                 = skip_typeref(type_left->pointer.points_to);
1152                         type_t *points_to_right
1153                                 = skip_typeref(type_right->pointer.points_to);
1154                         assign_error_t res = ASSIGN_SUCCESS;
1155
1156                         /* the left type has all qualifiers from the right type */
1157                         unsigned missing_qualifiers
1158                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1159                         if (missing_qualifiers != 0) {
1160                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1161                         }
1162
1163                         points_to_left  = get_unqualified_type(points_to_left);
1164                         points_to_right = get_unqualified_type(points_to_right);
1165
1166                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID))
1167                                 return res;
1168
1169                         if (is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1170                                 /* ISO/IEC 14882:1998(E) §C.1.2:6 */
1171                                 return c_mode & _CXX ? ASSIGN_ERROR_INCOMPATIBLE : res;
1172                         }
1173
1174                         if (!types_compatible(points_to_left, points_to_right)) {
1175                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1176                         }
1177
1178                         return res;
1179                 } else if (is_type_integer(type_right)) {
1180                         return ASSIGN_WARNING_POINTER_FROM_INT;
1181                 }
1182         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1183             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1184                 && is_type_pointer(type_right))) {
1185                 return ASSIGN_SUCCESS;
1186         } else if ((is_type_compound(type_left)  && is_type_compound(type_right))
1187                         || (is_type_builtin(type_left) && is_type_builtin(type_right))) {
1188                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1189                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1190                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1191                         return ASSIGN_SUCCESS;
1192                 }
1193         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1194                 return ASSIGN_WARNING_INT_FROM_POINTER;
1195         }
1196
1197         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1198                 return ASSIGN_SUCCESS;
1199
1200         return ASSIGN_ERROR_INCOMPATIBLE;
1201 }
1202
1203 static expression_t *parse_constant_expression(void)
1204 {
1205         expression_t *result = parse_sub_expression(PREC_CONDITIONAL);
1206
1207         if (!is_constant_expression(result)) {
1208                 errorf(&result->base.source_position,
1209                        "expression '%E' is not constant", result);
1210         }
1211
1212         return result;
1213 }
1214
1215 static expression_t *parse_assignment_expression(void)
1216 {
1217         return parse_sub_expression(PREC_ASSIGNMENT);
1218 }
1219
1220 static string_t parse_string_literals(void)
1221 {
1222         assert(token.type == T_STRING_LITERAL);
1223         string_t result = token.v.string;
1224
1225         next_token();
1226
1227         while (token.type == T_STRING_LITERAL) {
1228                 result = concat_strings(&result, &token.v.string);
1229                 next_token();
1230         }
1231
1232         return result;
1233 }
1234
1235 static const char *const gnu_attribute_names[GNU_AK_LAST] = {
1236         [GNU_AK_CONST]                  = "const",
1237         [GNU_AK_VOLATILE]               = "volatile",
1238         [GNU_AK_CDECL]                  = "cdecl",
1239         [GNU_AK_STDCALL]                = "stdcall",
1240         [GNU_AK_FASTCALL]               = "fastcall",
1241         [GNU_AK_DEPRECATED]             = "deprecated",
1242         [GNU_AK_NOINLINE]               = "noinline",
1243         [GNU_AK_NORETURN]               = "noreturn",
1244         [GNU_AK_NAKED]                  = "naked",
1245         [GNU_AK_PURE]                   = "pure",
1246         [GNU_AK_ALWAYS_INLINE]          = "always_inline",
1247         [GNU_AK_MALLOC]                 = "malloc",
1248         [GNU_AK_WEAK]                   = "weak",
1249         [GNU_AK_CONSTRUCTOR]            = "constructor",
1250         [GNU_AK_DESTRUCTOR]             = "destructor",
1251         [GNU_AK_NOTHROW]                = "nothrow",
1252         [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
1253         [GNU_AK_COMMON]                 = "common",
1254         [GNU_AK_NOCOMMON]               = "nocommon",
1255         [GNU_AK_PACKED]                 = "packed",
1256         [GNU_AK_SHARED]                 = "shared",
1257         [GNU_AK_NOTSHARED]              = "notshared",
1258         [GNU_AK_USED]                   = "used",
1259         [GNU_AK_UNUSED]                 = "unused",
1260         [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
1261         [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
1262         [GNU_AK_LONGCALL]               = "longcall",
1263         [GNU_AK_SHORTCALL]              = "shortcall",
1264         [GNU_AK_LONG_CALL]              = "long_call",
1265         [GNU_AK_SHORT_CALL]             = "short_call",
1266         [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
1267         [GNU_AK_INTERRUPT]              = "interrupt",
1268         [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
1269         [GNU_AK_NMI_HANDLER]            = "nmi_handler",
1270         [GNU_AK_NESTING]                = "nesting",
1271         [GNU_AK_NEAR]                   = "near",
1272         [GNU_AK_FAR]                    = "far",
1273         [GNU_AK_SIGNAL]                 = "signal",
1274         [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
1275         [GNU_AK_TINY_DATA]              = "tiny_data",
1276         [GNU_AK_SAVEALL]                = "saveall",
1277         [GNU_AK_FLATTEN]                = "flatten",
1278         [GNU_AK_SSEREGPARM]             = "sseregparm",
1279         [GNU_AK_EXTERNALLY_VISIBLE]     = "externally_visible",
1280         [GNU_AK_RETURN_TWICE]           = "return_twice",
1281         [GNU_AK_MAY_ALIAS]              = "may_alias",
1282         [GNU_AK_MS_STRUCT]              = "ms_struct",
1283         [GNU_AK_GCC_STRUCT]             = "gcc_struct",
1284         [GNU_AK_DLLIMPORT]              = "dllimport",
1285         [GNU_AK_DLLEXPORT]              = "dllexport",
1286         [GNU_AK_ALIGNED]                = "aligned",
1287         [GNU_AK_ALIAS]                  = "alias",
1288         [GNU_AK_SECTION]                = "section",
1289         [GNU_AK_FORMAT]                 = "format",
1290         [GNU_AK_FORMAT_ARG]             = "format_arg",
1291         [GNU_AK_WEAKREF]                = "weakref",
1292         [GNU_AK_NONNULL]                = "nonnull",
1293         [GNU_AK_TLS_MODEL]              = "tls_model",
1294         [GNU_AK_VISIBILITY]             = "visibility",
1295         [GNU_AK_REGPARM]                = "regparm",
1296         [GNU_AK_MODE]                   = "mode",
1297         [GNU_AK_MODEL]                  = "model",
1298         [GNU_AK_TRAP_EXIT]              = "trap_exit",
1299         [GNU_AK_SP_SWITCH]              = "sp_switch",
1300         [GNU_AK_SENTINEL]               = "sentinel"
1301 };
1302
1303 /**
1304  * compare two string, ignoring double underscores on the second.
1305  */
1306 static int strcmp_underscore(const char *s1, const char *s2)
1307 {
1308         if (s2[0] == '_' && s2[1] == '_') {
1309                 size_t len2 = strlen(s2);
1310                 size_t len1 = strlen(s1);
1311                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1312                         return strncmp(s1, s2+2, len2-4);
1313                 }
1314         }
1315
1316         return strcmp(s1, s2);
1317 }
1318
1319 /**
1320  * Allocate a new gnu temporal attribute of given kind.
1321  */
1322 static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
1323 {
1324         gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
1325         attribute->kind            = kind;
1326         attribute->next            = NULL;
1327         attribute->invalid         = false;
1328         attribute->have_arguments  = false;
1329
1330         return attribute;
1331 }
1332
1333 /**
1334  * Parse one constant expression argument of the given attribute.
1335  */
1336 static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
1337 {
1338         expression_t *expression;
1339         add_anchor_token(')');
1340         expression = parse_constant_expression();
1341         rem_anchor_token(')');
1342         expect(')', end_error);
1343         attribute->u.argument = fold_constant(expression);
1344         return;
1345 end_error:
1346         attribute->invalid = true;
1347 }
1348
1349 /**
1350  * Parse a list of constant expressions arguments of the given attribute.
1351  */
1352 static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
1353 {
1354         argument_list_t **list = &attribute->u.arguments;
1355         argument_list_t  *entry;
1356         expression_t     *expression;
1357         add_anchor_token(')');
1358         add_anchor_token(',');
1359         while (true) {
1360                 expression = parse_constant_expression();
1361                 entry = obstack_alloc(&temp_obst, sizeof(entry));
1362                 entry->argument = fold_constant(expression);
1363                 entry->next     = NULL;
1364                 *list = entry;
1365                 list = &entry->next;
1366                 if (token.type != ',')
1367                         break;
1368                 next_token();
1369         }
1370         rem_anchor_token(',');
1371         rem_anchor_token(')');
1372         expect(')', end_error);
1373         return;
1374 end_error:
1375         attribute->invalid = true;
1376 }
1377
1378 /**
1379  * Parse one string literal argument of the given attribute.
1380  */
1381 static void parse_gnu_attribute_string_arg(gnu_attribute_t *attribute,
1382                                            string_t *string)
1383 {
1384         add_anchor_token('(');
1385         if (token.type != T_STRING_LITERAL) {
1386                 parse_error_expected("while parsing attribute directive",
1387                                      T_STRING_LITERAL, NULL);
1388                 goto end_error;
1389         }
1390         *string = parse_string_literals();
1391         rem_anchor_token('(');
1392         expect(')', end_error);
1393         return;
1394 end_error:
1395         attribute->invalid = true;
1396 }
1397
1398 /**
1399  * Parse one tls model of the given attribute.
1400  */
1401 static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
1402 {
1403         static const char *const tls_models[] = {
1404                 "global-dynamic",
1405                 "local-dynamic",
1406                 "initial-exec",
1407                 "local-exec"
1408         };
1409         string_t string = { NULL, 0 };
1410         parse_gnu_attribute_string_arg(attribute, &string);
1411         if (string.begin != NULL) {
1412                 for (size_t i = 0; i < 4; ++i) {
1413                         if (strcmp(tls_models[i], string.begin) == 0) {
1414                                 attribute->u.value = i;
1415                                 return;
1416                         }
1417                 }
1418                 errorf(HERE, "'%s' is an unrecognized tls model", string.begin);
1419         }
1420         attribute->invalid = true;
1421 }
1422
1423 /**
1424  * Parse one tls model of the given attribute.
1425  */
1426 static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
1427 {
1428         static const char *const visibilities[] = {
1429                 "default",
1430                 "protected",
1431                 "hidden",
1432                 "internal"
1433         };
1434         string_t string = { NULL, 0 };
1435         parse_gnu_attribute_string_arg(attribute, &string);
1436         if (string.begin != NULL) {
1437                 for (size_t i = 0; i < 4; ++i) {
1438                         if (strcmp(visibilities[i], string.begin) == 0) {
1439                                 attribute->u.value = i;
1440                                 return;
1441                         }
1442                 }
1443                 errorf(HERE, "'%s' is an unrecognized visibility", string.begin);
1444         }
1445         attribute->invalid = true;
1446 }
1447
1448 /**
1449  * Parse one (code) model of the given attribute.
1450  */
1451 static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
1452 {
1453         static const char *const visibilities[] = {
1454                 "small",
1455                 "medium",
1456                 "large"
1457         };
1458         string_t string = { NULL, 0 };
1459         parse_gnu_attribute_string_arg(attribute, &string);
1460         if (string.begin != NULL) {
1461                 for (int i = 0; i < 3; ++i) {
1462                         if (strcmp(visibilities[i], string.begin) == 0) {
1463                                 attribute->u.value = i;
1464                                 return;
1465                         }
1466                 }
1467                 errorf(HERE, "'%s' is an unrecognized model", string.begin);
1468         }
1469         attribute->invalid = true;
1470 }
1471
1472 /**
1473  * Parse one mode of the given attribute.
1474  */
1475 static void parse_gnu_attribute_mode_arg(gnu_attribute_t *attribute)
1476 {
1477         /* TODO: find out what is allowed here... */
1478
1479         /* at least: byte, word, pointer, list of machine modes
1480          * __XXX___ is interpreted as XXX */
1481         add_anchor_token(')');
1482
1483         if (token.type != T_IDENTIFIER) {
1484                 expect(T_IDENTIFIER, end_error);
1485         }
1486
1487         /* This isn't really correct, the backend should provide a list of machine
1488          * specific modes (according to gcc philosophy that is...) */
1489         const char *symbol_str = token.v.symbol->string;
1490         if (strcmp_underscore("QI",   symbol_str) == 0 ||
1491             strcmp_underscore("byte", symbol_str) == 0) {
1492                 attribute->u.akind = ATOMIC_TYPE_CHAR;
1493         } else if (strcmp_underscore("HI", symbol_str) == 0) {
1494                 attribute->u.akind = ATOMIC_TYPE_SHORT;
1495         } else if (strcmp_underscore("SI",      symbol_str) == 0
1496                 || strcmp_underscore("word",    symbol_str) == 0
1497                 || strcmp_underscore("pointer", symbol_str) == 0) {
1498                 attribute->u.akind = ATOMIC_TYPE_INT;
1499         } else if (strcmp_underscore("DI", symbol_str) == 0) {
1500                 attribute->u.akind = ATOMIC_TYPE_LONGLONG;
1501         } else {
1502                 if (warning.other)
1503                         warningf(HERE, "ignoring unknown mode '%s'", symbol_str);
1504                 attribute->invalid = true;
1505         }
1506         next_token();
1507
1508         rem_anchor_token(')');
1509         expect(')', end_error);
1510         return;
1511 end_error:
1512         attribute->invalid = true;
1513 }
1514
1515 /**
1516  * Parse one interrupt argument of the given attribute.
1517  */
1518 static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
1519 {
1520         static const char *const interrupts[] = {
1521                 "IRQ",
1522                 "FIQ",
1523                 "SWI",
1524                 "ABORT",
1525                 "UNDEF"
1526         };
1527         string_t string = { NULL, 0 };
1528         parse_gnu_attribute_string_arg(attribute, &string);
1529         if (string.begin != NULL) {
1530                 for (size_t i = 0; i < 5; ++i) {
1531                         if (strcmp(interrupts[i], string.begin) == 0) {
1532                                 attribute->u.value = i;
1533                                 return;
1534                         }
1535                 }
1536                 errorf(HERE, "'%s' is not an interrupt", string.begin);
1537         }
1538         attribute->invalid = true;
1539 }
1540
1541 /**
1542  * Parse ( identifier, const expression, const expression )
1543  */
1544 static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
1545 {
1546         static const char *const format_names[] = {
1547                 "printf",
1548                 "scanf",
1549                 "strftime",
1550                 "strfmon"
1551         };
1552         int i;
1553
1554         if (token.type != T_IDENTIFIER) {
1555                 parse_error_expected("while parsing format attribute directive", T_IDENTIFIER, NULL);
1556                 goto end_error;
1557         }
1558         const char *name = token.v.symbol->string;
1559         for (i = 0; i < 4; ++i) {
1560                 if (strcmp_underscore(format_names[i], name) == 0)
1561                         break;
1562         }
1563         if (i >= 4) {
1564                 if (warning.attribute)
1565                         warningf(HERE, "'%s' is an unrecognized format function type", name);
1566         }
1567         next_token();
1568
1569         expect(',', end_error);
1570         add_anchor_token(')');
1571         add_anchor_token(',');
1572         parse_constant_expression();
1573         rem_anchor_token(',');
1574         rem_anchor_token(')');
1575
1576         expect(',', end_error);
1577         add_anchor_token(')');
1578         parse_constant_expression();
1579         rem_anchor_token(')');
1580         expect(')', end_error);
1581         return;
1582 end_error:
1583         attribute->u.value = true;
1584 }
1585
1586 /**
1587  * Check that a given GNU attribute has no arguments.
1588  */
1589 static void check_no_argument(gnu_attribute_t *attribute, const char *name)
1590 {
1591         if (!attribute->have_arguments)
1592                 return;
1593
1594         /* should have no arguments */
1595         errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1596         eat_until_matching_token('(');
1597         /* we have already consumed '(', so we stop before ')', eat it */
1598         eat(')');
1599         attribute->invalid = true;
1600 }
1601
1602 /**
1603  * Parse one GNU attribute.
1604  *
1605  * Note that attribute names can be specified WITH or WITHOUT
1606  * double underscores, ie const or __const__.
1607  *
1608  * The following attributes are parsed without arguments
1609  *  const
1610  *  volatile
1611  *  cdecl
1612  *  stdcall
1613  *  fastcall
1614  *  deprecated
1615  *  noinline
1616  *  noreturn
1617  *  naked
1618  *  pure
1619  *  always_inline
1620  *  malloc
1621  *  weak
1622  *  constructor
1623  *  destructor
1624  *  nothrow
1625  *  transparent_union
1626  *  common
1627  *  nocommon
1628  *  packed
1629  *  shared
1630  *  notshared
1631  *  used
1632  *  unused
1633  *  no_instrument_function
1634  *  warn_unused_result
1635  *  longcall
1636  *  shortcall
1637  *  long_call
1638  *  short_call
1639  *  function_vector
1640  *  interrupt_handler
1641  *  nmi_handler
1642  *  nesting
1643  *  near
1644  *  far
1645  *  signal
1646  *  eightbit_data
1647  *  tiny_data
1648  *  saveall
1649  *  flatten
1650  *  sseregparm
1651  *  externally_visible
1652  *  return_twice
1653  *  may_alias
1654  *  ms_struct
1655  *  gcc_struct
1656  *  dllimport
1657  *  dllexport
1658  *
1659  * The following attributes are parsed with arguments
1660  *  aligned( const expression )
1661  *  alias( string literal )
1662  *  section( string literal )
1663  *  format( identifier, const expression, const expression )
1664  *  format_arg( const expression )
1665  *  tls_model( string literal )
1666  *  visibility( string literal )
1667  *  regparm( const expression )
1668  *  model( string leteral )
1669  *  trap_exit( const expression )
1670  *  sp_switch( string literal )
1671  *
1672  * The following attributes might have arguments
1673  *  weak_ref( string literal )
1674  *  non_null( const expression // ',' )
1675  *  interrupt( string literal )
1676  *  sentinel( constant expression )
1677  */
1678 static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
1679 {
1680         gnu_attribute_t *head      = *attributes;
1681         gnu_attribute_t *last      = *attributes;
1682         decl_modifiers_t modifiers = 0;
1683         gnu_attribute_t *attribute;
1684
1685         eat(T___attribute__);
1686         expect('(', end_error);
1687         expect('(', end_error);
1688
1689         if (token.type != ')') {
1690                 /* find the end of the list */
1691                 if (last != NULL) {
1692                         while (last->next != NULL)
1693                                 last = last->next;
1694                 }
1695
1696                 /* non-empty attribute list */
1697                 while (true) {
1698                         const char *name;
1699                         if (token.type == T_const) {
1700                                 name = "const";
1701                         } else if (token.type == T_volatile) {
1702                                 name = "volatile";
1703                         } else if (token.type == T_cdecl) {
1704                                 /* __attribute__((cdecl)), WITH ms mode */
1705                                 name = "cdecl";
1706                         } else if (token.type == T_IDENTIFIER) {
1707                                 const symbol_t *sym = token.v.symbol;
1708                                 name = sym->string;
1709                         } else {
1710                                 parse_error_expected("while parsing GNU attribute", T_IDENTIFIER, NULL);
1711                                 break;
1712                         }
1713
1714                         next_token();
1715
1716                         int i;
1717                         for (i = 0; i < GNU_AK_LAST; ++i) {
1718                                 if (strcmp_underscore(gnu_attribute_names[i], name) == 0)
1719                                         break;
1720                         }
1721                         gnu_attribute_kind_t kind = (gnu_attribute_kind_t)i;
1722
1723                         attribute = NULL;
1724                         if (kind == GNU_AK_LAST) {
1725                                 if (warning.attribute)
1726                                         warningf(HERE, "'%s' attribute directive ignored", name);
1727
1728                                 /* skip possible arguments */
1729                                 if (token.type == '(') {
1730                                         eat_until_matching_token(')');
1731                                 }
1732                         } else {
1733                                 /* check for arguments */
1734                                 attribute = allocate_gnu_attribute(kind);
1735                                 if (token.type == '(') {
1736                                         next_token();
1737                                         if (token.type == ')') {
1738                                                 /* empty args are allowed */
1739                                                 next_token();
1740                                         } else
1741                                                 attribute->have_arguments = true;
1742                                 }
1743
1744                                 switch (kind) {
1745                                 case GNU_AK_VOLATILE:
1746                                 case GNU_AK_NAKED:
1747                                 case GNU_AK_MALLOC:
1748                                 case GNU_AK_WEAK:
1749                                 case GNU_AK_COMMON:
1750                                 case GNU_AK_NOCOMMON:
1751                                 case GNU_AK_SHARED:
1752                                 case GNU_AK_NOTSHARED:
1753                                 case GNU_AK_NO_INSTRUMENT_FUNCTION:
1754                                 case GNU_AK_WARN_UNUSED_RESULT:
1755                                 case GNU_AK_LONGCALL:
1756                                 case GNU_AK_SHORTCALL:
1757                                 case GNU_AK_LONG_CALL:
1758                                 case GNU_AK_SHORT_CALL:
1759                                 case GNU_AK_FUNCTION_VECTOR:
1760                                 case GNU_AK_INTERRUPT_HANDLER:
1761                                 case GNU_AK_NMI_HANDLER:
1762                                 case GNU_AK_NESTING:
1763                                 case GNU_AK_NEAR:
1764                                 case GNU_AK_FAR:
1765                                 case GNU_AK_SIGNAL:
1766                                 case GNU_AK_EIGTHBIT_DATA:
1767                                 case GNU_AK_TINY_DATA:
1768                                 case GNU_AK_SAVEALL:
1769                                 case GNU_AK_FLATTEN:
1770                                 case GNU_AK_SSEREGPARM:
1771                                 case GNU_AK_EXTERNALLY_VISIBLE:
1772                                 case GNU_AK_RETURN_TWICE:
1773                                 case GNU_AK_MAY_ALIAS:
1774                                 case GNU_AK_MS_STRUCT:
1775                                 case GNU_AK_GCC_STRUCT:
1776                                         goto no_arg;
1777
1778                                 case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
1779                                 case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
1780                                 case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
1781                                 case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
1782                                 case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
1783                                 case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
1784                                 case GNU_AK_CONST:             modifiers |= DM_CONST;             goto no_arg;
1785                                 case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
1786                                 case GNU_AK_DLLIMPORT:         modifiers |= DM_DLLIMPORT;         goto no_arg;
1787                                 case GNU_AK_DLLEXPORT:         modifiers |= DM_DLLEXPORT;         goto no_arg;
1788                                 case GNU_AK_PACKED:            modifiers |= DM_PACKED;            goto no_arg;
1789                                 case GNU_AK_NOINLINE:          modifiers |= DM_NOINLINE;          goto no_arg;
1790                                 case GNU_AK_NORETURN:          modifiers |= DM_NORETURN;          goto no_arg;
1791                                 case GNU_AK_NOTHROW:           modifiers |= DM_NOTHROW;           goto no_arg;
1792                                 case GNU_AK_TRANSPARENT_UNION: modifiers |= DM_TRANSPARENT_UNION; goto no_arg;
1793                                 case GNU_AK_CONSTRUCTOR:       modifiers |= DM_CONSTRUCTOR;       goto no_arg;
1794                                 case GNU_AK_DESTRUCTOR:        modifiers |= DM_DESTRUCTOR;        goto no_arg;
1795                                 case GNU_AK_DEPRECATED:        modifiers |= DM_DEPRECATED;        goto no_arg;
1796
1797                                 case GNU_AK_ALIGNED:
1798                                         /* __align__ may be used without an argument */
1799                                         if (attribute->have_arguments) {
1800                                                 parse_gnu_attribute_const_arg(attribute);
1801                                         }
1802                                         break;
1803
1804                                 case GNU_AK_FORMAT_ARG:
1805                                 case GNU_AK_REGPARM:
1806                                 case GNU_AK_TRAP_EXIT:
1807                                         if (!attribute->have_arguments) {
1808                                                 /* should have arguments */
1809                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1810                                                 attribute->invalid = true;
1811                                         } else
1812                                                 parse_gnu_attribute_const_arg(attribute);
1813                                         break;
1814                                 case GNU_AK_ALIAS:
1815                                 case GNU_AK_SECTION:
1816                                 case GNU_AK_SP_SWITCH:
1817                                         if (!attribute->have_arguments) {
1818                                                 /* should have arguments */
1819                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1820                                                 attribute->invalid = true;
1821                                         } else
1822                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1823                                         break;
1824                                 case GNU_AK_FORMAT:
1825                                         if (!attribute->have_arguments) {
1826                                                 /* should have arguments */
1827                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1828                                                 attribute->invalid = true;
1829                                         } else
1830                                                 parse_gnu_attribute_format_args(attribute);
1831                                         break;
1832                                 case GNU_AK_WEAKREF:
1833                                         /* may have one string argument */
1834                                         if (attribute->have_arguments)
1835                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1836                                         break;
1837                                 case GNU_AK_NONNULL:
1838                                         if (attribute->have_arguments)
1839                                                 parse_gnu_attribute_const_arg_list(attribute);
1840                                         break;
1841                                 case GNU_AK_TLS_MODEL:
1842                                         if (!attribute->have_arguments) {
1843                                                 /* should have arguments */
1844                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1845                                         } else
1846                                                 parse_gnu_attribute_tls_model_arg(attribute);
1847                                         break;
1848                                 case GNU_AK_VISIBILITY:
1849                                         if (!attribute->have_arguments) {
1850                                                 /* should have arguments */
1851                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1852                                         } else
1853                                                 parse_gnu_attribute_visibility_arg(attribute);
1854                                         break;
1855                                 case GNU_AK_MODEL:
1856                                         if (!attribute->have_arguments) {
1857                                                 /* should have arguments */
1858                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1859                                         } else {
1860                                                 parse_gnu_attribute_model_arg(attribute);
1861                                         }
1862                                         break;
1863                                 case GNU_AK_MODE:
1864                                         if (!attribute->have_arguments) {
1865                                                 /* should have arguments */
1866                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1867                                         } else {
1868                                                 parse_gnu_attribute_mode_arg(attribute);
1869                                         }
1870                                         break;
1871                                 case GNU_AK_INTERRUPT:
1872                                         /* may have one string argument */
1873                                         if (attribute->have_arguments)
1874                                                 parse_gnu_attribute_interrupt_arg(attribute);
1875                                         break;
1876                                 case GNU_AK_SENTINEL:
1877                                         /* may have one string argument */
1878                                         if (attribute->have_arguments)
1879                                                 parse_gnu_attribute_const_arg(attribute);
1880                                         break;
1881                                 case GNU_AK_LAST:
1882                                         /* already handled */
1883                                         break;
1884
1885 no_arg:
1886                                         check_no_argument(attribute, name);
1887                                 }
1888                         }
1889                         if (attribute != NULL) {
1890                                 if (last != NULL) {
1891                                         last->next = attribute;
1892                                         last       = attribute;
1893                                 } else {
1894                                         head = last = attribute;
1895                                 }
1896                         }
1897
1898                         if (token.type != ',')
1899                                 break;
1900                         next_token();
1901                 }
1902         }
1903         expect(')', end_error);
1904         expect(')', end_error);
1905 end_error:
1906         *attributes = head;
1907
1908         return modifiers;
1909 }
1910
1911 /**
1912  * Parse GNU attributes.
1913  */
1914 static decl_modifiers_t parse_attributes(gnu_attribute_t **attributes)
1915 {
1916         decl_modifiers_t modifiers = 0;
1917
1918         while (true) {
1919                 switch (token.type) {
1920                 case T___attribute__:
1921                         modifiers |= parse_gnu_attribute(attributes);
1922                         continue;
1923
1924                 case T_asm:
1925                         next_token();
1926                         expect('(', end_error);
1927                         if (token.type != T_STRING_LITERAL) {
1928                                 parse_error_expected("while parsing assembler attribute",
1929                                                      T_STRING_LITERAL, NULL);
1930                                 eat_until_matching_token('(');
1931                                 break;
1932                         } else {
1933                                 parse_string_literals();
1934                         }
1935                         expect(')', end_error);
1936                         continue;
1937
1938                 case T_cdecl:     modifiers |= DM_CDECL;    break;
1939                 case T__fastcall: modifiers |= DM_FASTCALL; break;
1940                 case T__stdcall:  modifiers |= DM_STDCALL;  break;
1941
1942                 case T___thiscall:
1943                         /* TODO record modifier */
1944                         if (warning.other)
1945                                 warningf(HERE, "Ignoring declaration modifier %K", &token);
1946                         break;
1947
1948 end_error:
1949                 default: return modifiers;
1950                 }
1951
1952                 next_token();
1953         }
1954 }
1955
1956 static void mark_vars_read(expression_t *expr, entity_t *lhs_ent);
1957
1958 static entity_t *determine_lhs_ent(expression_t *const expr,
1959                                    entity_t *lhs_ent)
1960 {
1961         switch (expr->kind) {
1962                 case EXPR_REFERENCE: {
1963                         entity_t *const entity = expr->reference.entity;
1964                         /* we should only find variables as lvalues... */
1965                         if (entity->base.kind != ENTITY_VARIABLE
1966                                         && entity->base.kind != ENTITY_PARAMETER)
1967                                 return NULL;
1968
1969                         return entity;
1970                 }
1971
1972                 case EXPR_ARRAY_ACCESS: {
1973                         expression_t *const ref = expr->array_access.array_ref;
1974                         entity_t     *      ent = NULL;
1975                         if (is_type_array(skip_typeref(revert_automatic_type_conversion(ref)))) {
1976                                 ent     = determine_lhs_ent(ref, lhs_ent);
1977                                 lhs_ent = ent;
1978                         } else {
1979                                 mark_vars_read(expr->select.compound, lhs_ent);
1980                         }
1981                         mark_vars_read(expr->array_access.index, lhs_ent);
1982                         return ent;
1983                 }
1984
1985                 case EXPR_SELECT: {
1986                         if (is_type_compound(skip_typeref(expr->base.type))) {
1987                                 return determine_lhs_ent(expr->select.compound, lhs_ent);
1988                         } else {
1989                                 mark_vars_read(expr->select.compound, lhs_ent);
1990                                 return NULL;
1991                         }
1992                 }
1993
1994                 case EXPR_UNARY_DEREFERENCE: {
1995                         expression_t *const val = expr->unary.value;
1996                         if (val->kind == EXPR_UNARY_TAKE_ADDRESS) {
1997                                 /* *&x is a NOP */
1998                                 return determine_lhs_ent(val->unary.value, lhs_ent);
1999                         } else {
2000                                 mark_vars_read(val, NULL);
2001                                 return NULL;
2002                         }
2003                 }
2004
2005                 default:
2006                         mark_vars_read(expr, NULL);
2007                         return NULL;
2008         }
2009 }
2010
2011 #define ENT_ANY ((entity_t*)-1)
2012
2013 /**
2014  * Mark declarations, which are read.  This is used to detect variables, which
2015  * are never read.
2016  * Example:
2017  * x = x + 1;
2018  *   x is not marked as "read", because it is only read to calculate its own new
2019  *   value.
2020  *
2021  * x += y; y += x;
2022  *   x and y are not detected as "not read", because multiple variables are
2023  *   involved.
2024  */
2025 static void mark_vars_read(expression_t *const expr, entity_t *lhs_ent)
2026 {
2027         switch (expr->kind) {
2028                 case EXPR_REFERENCE: {
2029                         entity_t *const entity = expr->reference.entity;
2030                         if (entity->kind != ENTITY_VARIABLE
2031                                         && entity->kind != ENTITY_PARAMETER)
2032                                 return;
2033
2034                         if (lhs_ent != entity && lhs_ent != ENT_ANY) {
2035                                 if (entity->kind == ENTITY_VARIABLE) {
2036                                         entity->variable.read = true;
2037                                 } else {
2038                                         entity->parameter.read = true;
2039                                 }
2040                         }
2041                         return;
2042                 }
2043
2044                 case EXPR_CALL:
2045                         // TODO respect pure/const
2046                         mark_vars_read(expr->call.function, NULL);
2047                         for (call_argument_t *arg = expr->call.arguments; arg != NULL; arg = arg->next) {
2048                                 mark_vars_read(arg->expression, NULL);
2049                         }
2050                         return;
2051
2052                 case EXPR_CONDITIONAL:
2053                         // TODO lhs_decl should depend on whether true/false have an effect
2054                         mark_vars_read(expr->conditional.condition, NULL);
2055                         if (expr->conditional.true_expression != NULL)
2056                                 mark_vars_read(expr->conditional.true_expression, lhs_ent);
2057                         mark_vars_read(expr->conditional.false_expression, lhs_ent);
2058                         return;
2059
2060                 case EXPR_SELECT:
2061                         if (lhs_ent == ENT_ANY
2062                                         && !is_type_compound(skip_typeref(expr->base.type)))
2063                                 lhs_ent = NULL;
2064                         mark_vars_read(expr->select.compound, lhs_ent);
2065                         return;
2066
2067                 case EXPR_ARRAY_ACCESS: {
2068                         expression_t *const ref = expr->array_access.array_ref;
2069                         mark_vars_read(ref, lhs_ent);
2070                         lhs_ent = determine_lhs_ent(ref, lhs_ent);
2071                         mark_vars_read(expr->array_access.index, lhs_ent);
2072                         return;
2073                 }
2074
2075                 case EXPR_VA_ARG:
2076                         mark_vars_read(expr->va_arge.ap, lhs_ent);
2077                         return;
2078
2079                 case EXPR_UNARY_CAST:
2080                         /* Special case: Use void cast to mark a variable as "read" */
2081                         if (is_type_atomic(skip_typeref(expr->base.type), ATOMIC_TYPE_VOID))
2082                                 lhs_ent = NULL;
2083                         goto unary;
2084
2085
2086                 case EXPR_UNARY_THROW:
2087                         if (expr->unary.value == NULL)
2088                                 return;
2089                         /* FALLTHROUGH */
2090                 case EXPR_UNARY_DEREFERENCE:
2091                 case EXPR_UNARY_DELETE:
2092                 case EXPR_UNARY_DELETE_ARRAY:
2093                         if (lhs_ent == ENT_ANY)
2094                                 lhs_ent = NULL;
2095                         goto unary;
2096
2097                 case EXPR_UNARY_NEGATE:
2098                 case EXPR_UNARY_PLUS:
2099                 case EXPR_UNARY_BITWISE_NEGATE:
2100                 case EXPR_UNARY_NOT:
2101                 case EXPR_UNARY_TAKE_ADDRESS:
2102                 case EXPR_UNARY_POSTFIX_INCREMENT:
2103                 case EXPR_UNARY_POSTFIX_DECREMENT:
2104                 case EXPR_UNARY_PREFIX_INCREMENT:
2105                 case EXPR_UNARY_PREFIX_DECREMENT:
2106                 case EXPR_UNARY_CAST_IMPLICIT:
2107                 case EXPR_UNARY_ASSUME:
2108 unary:
2109                         mark_vars_read(expr->unary.value, lhs_ent);
2110                         return;
2111
2112                 case EXPR_BINARY_ADD:
2113                 case EXPR_BINARY_SUB:
2114                 case EXPR_BINARY_MUL:
2115                 case EXPR_BINARY_DIV:
2116                 case EXPR_BINARY_MOD:
2117                 case EXPR_BINARY_EQUAL:
2118                 case EXPR_BINARY_NOTEQUAL:
2119                 case EXPR_BINARY_LESS:
2120                 case EXPR_BINARY_LESSEQUAL:
2121                 case EXPR_BINARY_GREATER:
2122                 case EXPR_BINARY_GREATEREQUAL:
2123                 case EXPR_BINARY_BITWISE_AND:
2124                 case EXPR_BINARY_BITWISE_OR:
2125                 case EXPR_BINARY_BITWISE_XOR:
2126                 case EXPR_BINARY_LOGICAL_AND:
2127                 case EXPR_BINARY_LOGICAL_OR:
2128                 case EXPR_BINARY_SHIFTLEFT:
2129                 case EXPR_BINARY_SHIFTRIGHT:
2130                 case EXPR_BINARY_COMMA:
2131                 case EXPR_BINARY_ISGREATER:
2132                 case EXPR_BINARY_ISGREATEREQUAL:
2133                 case EXPR_BINARY_ISLESS:
2134                 case EXPR_BINARY_ISLESSEQUAL:
2135                 case EXPR_BINARY_ISLESSGREATER:
2136                 case EXPR_BINARY_ISUNORDERED:
2137                         mark_vars_read(expr->binary.left,  lhs_ent);
2138                         mark_vars_read(expr->binary.right, lhs_ent);
2139                         return;
2140
2141                 case EXPR_BINARY_ASSIGN:
2142                 case EXPR_BINARY_MUL_ASSIGN:
2143                 case EXPR_BINARY_DIV_ASSIGN:
2144                 case EXPR_BINARY_MOD_ASSIGN:
2145                 case EXPR_BINARY_ADD_ASSIGN:
2146                 case EXPR_BINARY_SUB_ASSIGN:
2147                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:
2148                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:
2149                 case EXPR_BINARY_BITWISE_AND_ASSIGN:
2150                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:
2151                 case EXPR_BINARY_BITWISE_OR_ASSIGN: {
2152                         if (lhs_ent == ENT_ANY)
2153                                 lhs_ent = NULL;
2154                         lhs_ent = determine_lhs_ent(expr->binary.left, lhs_ent);
2155                         mark_vars_read(expr->binary.right, lhs_ent);
2156                         return;
2157                 }
2158
2159                 case EXPR_VA_START:
2160                         determine_lhs_ent(expr->va_starte.ap, lhs_ent);
2161                         return;
2162
2163                 case EXPR_UNKNOWN:
2164                 case EXPR_INVALID:
2165                 case EXPR_CONST:
2166                 case EXPR_CHARACTER_CONSTANT:
2167                 case EXPR_WIDE_CHARACTER_CONSTANT:
2168                 case EXPR_STRING_LITERAL:
2169                 case EXPR_WIDE_STRING_LITERAL:
2170                 case EXPR_COMPOUND_LITERAL: // TODO init?
2171                 case EXPR_SIZEOF:
2172                 case EXPR_CLASSIFY_TYPE:
2173                 case EXPR_ALIGNOF:
2174                 case EXPR_FUNCNAME:
2175                 case EXPR_BUILTIN_SYMBOL:
2176                 case EXPR_BUILTIN_CONSTANT_P:
2177                 case EXPR_BUILTIN_PREFETCH:
2178                 case EXPR_OFFSETOF:
2179                 case EXPR_STATEMENT: // TODO
2180                 case EXPR_LABEL_ADDRESS:
2181                 case EXPR_REFERENCE_ENUM_VALUE:
2182                         return;
2183         }
2184
2185         panic("unhandled expression");
2186 }
2187
2188 static designator_t *parse_designation(void)
2189 {
2190         designator_t *result = NULL;
2191         designator_t *last   = NULL;
2192
2193         while (true) {
2194                 designator_t *designator;
2195                 switch (token.type) {
2196                 case '[':
2197                         designator = allocate_ast_zero(sizeof(designator[0]));
2198                         designator->source_position = token.source_position;
2199                         next_token();
2200                         add_anchor_token(']');
2201                         designator->array_index = parse_constant_expression();
2202                         rem_anchor_token(']');
2203                         expect(']', end_error);
2204                         break;
2205                 case '.':
2206                         designator = allocate_ast_zero(sizeof(designator[0]));
2207                         designator->source_position = token.source_position;
2208                         next_token();
2209                         if (token.type != T_IDENTIFIER) {
2210                                 parse_error_expected("while parsing designator",
2211                                                      T_IDENTIFIER, NULL);
2212                                 return NULL;
2213                         }
2214                         designator->symbol = token.v.symbol;
2215                         next_token();
2216                         break;
2217                 default:
2218                         expect('=', end_error);
2219                         return result;
2220                 }
2221
2222                 assert(designator != NULL);
2223                 if (last != NULL) {
2224                         last->next = designator;
2225                 } else {
2226                         result = designator;
2227                 }
2228                 last = designator;
2229         }
2230 end_error:
2231         return NULL;
2232 }
2233
2234 static initializer_t *initializer_from_string(array_type_t *type,
2235                                               const string_t *const string)
2236 {
2237         /* TODO: check len vs. size of array type */
2238         (void) type;
2239
2240         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
2241         initializer->string.string = *string;
2242
2243         return initializer;
2244 }
2245
2246 static initializer_t *initializer_from_wide_string(array_type_t *const type,
2247                                                    wide_string_t *const string)
2248 {
2249         /* TODO: check len vs. size of array type */
2250         (void) type;
2251
2252         initializer_t *const initializer =
2253                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
2254         initializer->wide_string.string = *string;
2255
2256         return initializer;
2257 }
2258
2259 /**
2260  * Build an initializer from a given expression.
2261  */
2262 static initializer_t *initializer_from_expression(type_t *orig_type,
2263                                                   expression_t *expression)
2264 {
2265         /* TODO check that expression is a constant expression */
2266
2267         /* § 6.7.8.14/15 char array may be initialized by string literals */
2268         type_t *type           = skip_typeref(orig_type);
2269         type_t *expr_type_orig = expression->base.type;
2270         type_t *expr_type      = skip_typeref(expr_type_orig);
2271         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
2272                 array_type_t *const array_type   = &type->array;
2273                 type_t       *const element_type = skip_typeref(array_type->element_type);
2274
2275                 if (element_type->kind == TYPE_ATOMIC) {
2276                         atomic_type_kind_t akind = element_type->atomic.akind;
2277                         switch (expression->kind) {
2278                                 case EXPR_STRING_LITERAL:
2279                                         if (akind == ATOMIC_TYPE_CHAR
2280                                                         || akind == ATOMIC_TYPE_SCHAR
2281                                                         || akind == ATOMIC_TYPE_UCHAR) {
2282                                                 return initializer_from_string(array_type,
2283                                                         &expression->string.value);
2284                                         }
2285
2286                                 case EXPR_WIDE_STRING_LITERAL: {
2287                                         type_t *bare_wchar_type = skip_typeref(type_wchar_t);
2288                                         if (get_unqualified_type(element_type) == bare_wchar_type) {
2289                                                 return initializer_from_wide_string(array_type,
2290                                                         &expression->wide_string.value);
2291                                         }
2292                                 }
2293
2294                                 default:
2295                                         break;
2296                         }
2297                 }
2298         }
2299
2300         assign_error_t error = semantic_assign(type, expression);
2301         if (error == ASSIGN_ERROR_INCOMPATIBLE)
2302                 return NULL;
2303         report_assign_error(error, type, expression, "initializer",
2304                             &expression->base.source_position);
2305
2306         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
2307 #if 0
2308         if (type->kind == TYPE_BITFIELD) {
2309                 type = type->bitfield.base_type;
2310         }
2311 #endif
2312         result->value.value = create_implicit_cast(expression, type);
2313
2314         return result;
2315 }
2316
2317 /**
2318  * Checks if a given expression can be used as an constant initializer.
2319  */
2320 static bool is_initializer_constant(const expression_t *expression)
2321 {
2322         return is_constant_expression(expression)
2323                 || is_address_constant(expression);
2324 }
2325
2326 /**
2327  * Parses an scalar initializer.
2328  *
2329  * § 6.7.8.11; eat {} without warning
2330  */
2331 static initializer_t *parse_scalar_initializer(type_t *type,
2332                                                bool must_be_constant)
2333 {
2334         /* there might be extra {} hierarchies */
2335         int braces = 0;
2336         if (token.type == '{') {
2337                 if (warning.other)
2338                         warningf(HERE, "extra curly braces around scalar initializer");
2339                 do {
2340                         ++braces;
2341                         next_token();
2342                 } while (token.type == '{');
2343         }
2344
2345         expression_t *expression = parse_assignment_expression();
2346         mark_vars_read(expression, NULL);
2347         if (must_be_constant && !is_initializer_constant(expression)) {
2348                 errorf(&expression->base.source_position,
2349                        "Initialisation expression '%E' is not constant",
2350                        expression);
2351         }
2352
2353         initializer_t *initializer = initializer_from_expression(type, expression);
2354
2355         if (initializer == NULL) {
2356                 errorf(&expression->base.source_position,
2357                        "expression '%E' (type '%T') doesn't match expected type '%T'",
2358                        expression, expression->base.type, type);
2359                 /* TODO */
2360                 return NULL;
2361         }
2362
2363         bool additional_warning_displayed = false;
2364         while (braces > 0) {
2365                 if (token.type == ',') {
2366                         next_token();
2367                 }
2368                 if (token.type != '}') {
2369                         if (!additional_warning_displayed && warning.other) {
2370                                 warningf(HERE, "additional elements in scalar initializer");
2371                                 additional_warning_displayed = true;
2372                         }
2373                 }
2374                 eat_block();
2375                 braces--;
2376         }
2377
2378         return initializer;
2379 }
2380
2381 /**
2382  * An entry in the type path.
2383  */
2384 typedef struct type_path_entry_t type_path_entry_t;
2385 struct type_path_entry_t {
2386         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
2387         union {
2388                 size_t         index;          /**< For array types: the current index. */
2389                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
2390         } v;
2391 };
2392
2393 /**
2394  * A type path expression a position inside compound or array types.
2395  */
2396 typedef struct type_path_t type_path_t;
2397 struct type_path_t {
2398         type_path_entry_t *path;         /**< An flexible array containing the current path. */
2399         type_t            *top_type;     /**< type of the element the path points */
2400         size_t             max_index;    /**< largest index in outermost array */
2401 };
2402
2403 /**
2404  * Prints a type path for debugging.
2405  */
2406 static __attribute__((unused)) void debug_print_type_path(
2407                 const type_path_t *path)
2408 {
2409         size_t len = ARR_LEN(path->path);
2410
2411         for (size_t i = 0; i < len; ++i) {
2412                 const type_path_entry_t *entry = & path->path[i];
2413
2414                 type_t *type = skip_typeref(entry->type);
2415                 if (is_type_compound(type)) {
2416                         /* in gcc mode structs can have no members */
2417                         if (entry->v.compound_entry == NULL) {
2418                                 assert(i == len-1);
2419                                 continue;
2420                         }
2421                         fprintf(stderr, ".%s",
2422                                 entry->v.compound_entry->base.symbol->string);
2423                 } else if (is_type_array(type)) {
2424                         fprintf(stderr, "[%u]", (unsigned) entry->v.index);
2425                 } else {
2426                         fprintf(stderr, "-INVALID-");
2427                 }
2428         }
2429         if (path->top_type != NULL) {
2430                 fprintf(stderr, "  (");
2431                 print_type(path->top_type);
2432                 fprintf(stderr, ")");
2433         }
2434 }
2435
2436 /**
2437  * Return the top type path entry, ie. in a path
2438  * (type).a.b returns the b.
2439  */
2440 static type_path_entry_t *get_type_path_top(const type_path_t *path)
2441 {
2442         size_t len = ARR_LEN(path->path);
2443         assert(len > 0);
2444         return &path->path[len-1];
2445 }
2446
2447 /**
2448  * Enlarge the type path by an (empty) element.
2449  */
2450 static type_path_entry_t *append_to_type_path(type_path_t *path)
2451 {
2452         size_t len = ARR_LEN(path->path);
2453         ARR_RESIZE(type_path_entry_t, path->path, len+1);
2454
2455         type_path_entry_t *result = & path->path[len];
2456         memset(result, 0, sizeof(result[0]));
2457         return result;
2458 }
2459
2460 /**
2461  * Descending into a sub-type. Enter the scope of the current top_type.
2462  */
2463 static void descend_into_subtype(type_path_t *path)
2464 {
2465         type_t *orig_top_type = path->top_type;
2466         type_t *top_type      = skip_typeref(orig_top_type);
2467
2468         type_path_entry_t *top = append_to_type_path(path);
2469         top->type              = top_type;
2470
2471         if (is_type_compound(top_type)) {
2472                 compound_t *compound  = top_type->compound.compound;
2473                 entity_t   *entry     = compound->members.entities;
2474
2475                 if (entry != NULL) {
2476                         assert(entry->kind == ENTITY_COMPOUND_MEMBER);
2477                         top->v.compound_entry = &entry->declaration;
2478                         path->top_type = entry->declaration.type;
2479                 } else {
2480                         path->top_type = NULL;
2481                 }
2482         } else if (is_type_array(top_type)) {
2483                 top->v.index   = 0;
2484                 path->top_type = top_type->array.element_type;
2485         } else {
2486                 assert(!is_type_valid(top_type));
2487         }
2488 }
2489
2490 /**
2491  * Pop an entry from the given type path, ie. returning from
2492  * (type).a.b to (type).a
2493  */
2494 static void ascend_from_subtype(type_path_t *path)
2495 {
2496         type_path_entry_t *top = get_type_path_top(path);
2497
2498         path->top_type = top->type;
2499
2500         size_t len = ARR_LEN(path->path);
2501         ARR_RESIZE(type_path_entry_t, path->path, len-1);
2502 }
2503
2504 /**
2505  * Pop entries from the given type path until the given
2506  * path level is reached.
2507  */
2508 static void ascend_to(type_path_t *path, size_t top_path_level)
2509 {
2510         size_t len = ARR_LEN(path->path);
2511
2512         while (len > top_path_level) {
2513                 ascend_from_subtype(path);
2514                 len = ARR_LEN(path->path);
2515         }
2516 }
2517
2518 static bool walk_designator(type_path_t *path, const designator_t *designator,
2519                             bool used_in_offsetof)
2520 {
2521         for (; designator != NULL; designator = designator->next) {
2522                 type_path_entry_t *top       = get_type_path_top(path);
2523                 type_t            *orig_type = top->type;
2524
2525                 type_t *type = skip_typeref(orig_type);
2526
2527                 if (designator->symbol != NULL) {
2528                         symbol_t *symbol = designator->symbol;
2529                         if (!is_type_compound(type)) {
2530                                 if (is_type_valid(type)) {
2531                                         errorf(&designator->source_position,
2532                                                "'.%Y' designator used for non-compound type '%T'",
2533                                                symbol, orig_type);
2534                                 }
2535
2536                                 top->type             = type_error_type;
2537                                 top->v.compound_entry = NULL;
2538                                 orig_type             = type_error_type;
2539                         } else {
2540                                 compound_t *compound = type->compound.compound;
2541                                 entity_t   *iter     = compound->members.entities;
2542                                 for (; iter != NULL; iter = iter->base.next) {
2543                                         if (iter->base.symbol == symbol) {
2544                                                 break;
2545                                         }
2546                                 }
2547                                 if (iter == NULL) {
2548                                         errorf(&designator->source_position,
2549                                                "'%T' has no member named '%Y'", orig_type, symbol);
2550                                         goto failed;
2551                                 }
2552                                 assert(iter->kind == ENTITY_COMPOUND_MEMBER);
2553                                 if (used_in_offsetof) {
2554                                         type_t *real_type = skip_typeref(iter->declaration.type);
2555                                         if (real_type->kind == TYPE_BITFIELD) {
2556                                                 errorf(&designator->source_position,
2557                                                        "offsetof designator '%Y' may not specify bitfield",
2558                                                        symbol);
2559                                                 goto failed;
2560                                         }
2561                                 }
2562
2563                                 top->type             = orig_type;
2564                                 top->v.compound_entry = &iter->declaration;
2565                                 orig_type             = iter->declaration.type;
2566                         }
2567                 } else {
2568                         expression_t *array_index = designator->array_index;
2569                         assert(designator->array_index != NULL);
2570
2571                         if (!is_type_array(type)) {
2572                                 if (is_type_valid(type)) {
2573                                         errorf(&designator->source_position,
2574                                                "[%E] designator used for non-array type '%T'",
2575                                                array_index, orig_type);
2576                                 }
2577                                 goto failed;
2578                         }
2579
2580                         long index = fold_constant(array_index);
2581                         if (!used_in_offsetof) {
2582                                 if (index < 0) {
2583                                         errorf(&designator->source_position,
2584                                                "array index [%E] must be positive", array_index);
2585                                 } else if (type->array.size_constant) {
2586                                         long array_size = type->array.size;
2587                                         if (index >= array_size) {
2588                                                 errorf(&designator->source_position,
2589                                                        "designator [%E] (%d) exceeds array size %d",
2590                                                        array_index, index, array_size);
2591                                         }
2592                                 }
2593                         }
2594
2595                         top->type    = orig_type;
2596                         top->v.index = (size_t) index;
2597                         orig_type    = type->array.element_type;
2598                 }
2599                 path->top_type = orig_type;
2600
2601                 if (designator->next != NULL) {
2602                         descend_into_subtype(path);
2603                 }
2604         }
2605         return true;
2606
2607 failed:
2608         return false;
2609 }
2610
2611 static void advance_current_object(type_path_t *path, size_t top_path_level)
2612 {
2613         type_path_entry_t *top = get_type_path_top(path);
2614
2615         type_t *type = skip_typeref(top->type);
2616         if (is_type_union(type)) {
2617                 /* in unions only the first element is initialized */
2618                 top->v.compound_entry = NULL;
2619         } else if (is_type_struct(type)) {
2620                 declaration_t *entry = top->v.compound_entry;
2621
2622                 entity_t *next_entity = entry->base.next;
2623                 if (next_entity != NULL) {
2624                         assert(is_declaration(next_entity));
2625                         entry = &next_entity->declaration;
2626                 } else {
2627                         entry = NULL;
2628                 }
2629
2630                 top->v.compound_entry = entry;
2631                 if (entry != NULL) {
2632                         path->top_type = entry->type;
2633                         return;
2634                 }
2635         } else if (is_type_array(type)) {
2636                 assert(is_type_array(type));
2637
2638                 top->v.index++;
2639
2640                 if (!type->array.size_constant || top->v.index < type->array.size) {
2641                         return;
2642                 }
2643         } else {
2644                 assert(!is_type_valid(type));
2645                 return;
2646         }
2647
2648         /* we're past the last member of the current sub-aggregate, try if we
2649          * can ascend in the type hierarchy and continue with another subobject */
2650         size_t len = ARR_LEN(path->path);
2651
2652         if (len > top_path_level) {
2653                 ascend_from_subtype(path);
2654                 advance_current_object(path, top_path_level);
2655         } else {
2656                 path->top_type = NULL;
2657         }
2658 }
2659
2660 /**
2661  * skip until token is found.
2662  */
2663 static void skip_until(int type)
2664 {
2665         while (token.type != type) {
2666                 if (token.type == T_EOF)
2667                         return;
2668                 next_token();
2669         }
2670 }
2671
2672 /**
2673  * skip any {...} blocks until a closing bracket is reached.
2674  */
2675 static void skip_initializers(void)
2676 {
2677         if (token.type == '{')
2678                 next_token();
2679
2680         while (token.type != '}') {
2681                 if (token.type == T_EOF)
2682                         return;
2683                 if (token.type == '{') {
2684                         eat_block();
2685                         continue;
2686                 }
2687                 next_token();
2688         }
2689 }
2690
2691 static initializer_t *create_empty_initializer(void)
2692 {
2693         static initializer_t empty_initializer
2694                 = { .list = { { INITIALIZER_LIST }, 0 } };
2695         return &empty_initializer;
2696 }
2697
2698 /**
2699  * Parse a part of an initialiser for a struct or union,
2700  */
2701 static initializer_t *parse_sub_initializer(type_path_t *path,
2702                 type_t *outer_type, size_t top_path_level,
2703                 parse_initializer_env_t *env)
2704 {
2705         if (token.type == '}') {
2706                 /* empty initializer */
2707                 return create_empty_initializer();
2708         }
2709
2710         type_t *orig_type = path->top_type;
2711         type_t *type      = NULL;
2712
2713         if (orig_type == NULL) {
2714                 /* We are initializing an empty compound. */
2715         } else {
2716                 type = skip_typeref(orig_type);
2717         }
2718
2719         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2720
2721         while (true) {
2722                 designator_t *designator = NULL;
2723                 if (token.type == '.' || token.type == '[') {
2724                         designator = parse_designation();
2725                         goto finish_designator;
2726                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2727                         /* GNU-style designator ("identifier: value") */
2728                         designator = allocate_ast_zero(sizeof(designator[0]));
2729                         designator->source_position = token.source_position;
2730                         designator->symbol          = token.v.symbol;
2731                         eat(T_IDENTIFIER);
2732                         eat(':');
2733
2734 finish_designator:
2735                         /* reset path to toplevel, evaluate designator from there */
2736                         ascend_to(path, top_path_level);
2737                         if (!walk_designator(path, designator, false)) {
2738                                 /* can't continue after designation error */
2739                                 goto end_error;
2740                         }
2741
2742                         initializer_t *designator_initializer
2743                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2744                         designator_initializer->designator.designator = designator;
2745                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2746
2747                         orig_type = path->top_type;
2748                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2749                 }
2750
2751                 initializer_t *sub;
2752
2753                 if (token.type == '{') {
2754                         if (type != NULL && is_type_scalar(type)) {
2755                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2756                         } else {
2757                                 eat('{');
2758                                 if (type == NULL) {
2759                                         if (env->entity != NULL) {
2760                                                 errorf(HERE,
2761                                                      "extra brace group at end of initializer for '%Y'",
2762                                                      env->entity->base.symbol);
2763                                         } else {
2764                                                 errorf(HERE, "extra brace group at end of initializer");
2765                                         }
2766                                 } else
2767                                         descend_into_subtype(path);
2768
2769                                 add_anchor_token('}');
2770                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2771                                                             env);
2772                                 rem_anchor_token('}');
2773
2774                                 if (type != NULL) {
2775                                         ascend_from_subtype(path);
2776                                         expect('}', end_error);
2777                                 } else {
2778                                         expect('}', end_error);
2779                                         goto error_parse_next;
2780                                 }
2781                         }
2782                 } else {
2783                         /* must be an expression */
2784                         expression_t *expression = parse_assignment_expression();
2785
2786                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2787                                 errorf(&expression->base.source_position,
2788                                        "Initialisation expression '%E' is not constant",
2789                                        expression);
2790                         }
2791
2792                         if (type == NULL) {
2793                                 /* we are already outside, ... */
2794                                 type_t *const outer_type_skip = skip_typeref(outer_type);
2795                                 if (is_type_compound(outer_type_skip) &&
2796                                     !outer_type_skip->compound.compound->complete) {
2797                                         goto error_parse_next;
2798                                 }
2799                                 goto error_excess;
2800                         }
2801
2802                         /* handle { "string" } special case */
2803                         if ((expression->kind == EXPR_STRING_LITERAL
2804                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2805                                         && outer_type != NULL) {
2806                                 sub = initializer_from_expression(outer_type, expression);
2807                                 if (sub != NULL) {
2808                                         if (token.type == ',') {
2809                                                 next_token();
2810                                         }
2811                                         if (token.type != '}' && warning.other) {
2812                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2813                                                                  orig_type);
2814                                         }
2815                                         /* TODO: eat , ... */
2816                                         return sub;
2817                                 }
2818                         }
2819
2820                         /* descend into subtypes until expression matches type */
2821                         while (true) {
2822                                 orig_type = path->top_type;
2823                                 type      = skip_typeref(orig_type);
2824
2825                                 sub = initializer_from_expression(orig_type, expression);
2826                                 if (sub != NULL) {
2827                                         break;
2828                                 }
2829                                 if (!is_type_valid(type)) {
2830                                         goto end_error;
2831                                 }
2832                                 if (is_type_scalar(type)) {
2833                                         errorf(&expression->base.source_position,
2834                                                         "expression '%E' doesn't match expected type '%T'",
2835                                                         expression, orig_type);
2836                                         goto end_error;
2837                                 }
2838
2839                                 descend_into_subtype(path);
2840                         }
2841                 }
2842
2843                 /* update largest index of top array */
2844                 const type_path_entry_t *first      = &path->path[0];
2845                 type_t                  *first_type = first->type;
2846                 first_type                          = skip_typeref(first_type);
2847                 if (is_type_array(first_type)) {
2848                         size_t index = first->v.index;
2849                         if (index > path->max_index)
2850                                 path->max_index = index;
2851                 }
2852
2853                 if (type != NULL) {
2854                         /* append to initializers list */
2855                         ARR_APP1(initializer_t*, initializers, sub);
2856                 } else {
2857 error_excess:
2858                         if (warning.other) {
2859                                 if (env->entity != NULL) {
2860                                         warningf(HERE, "excess elements in struct initializer for '%Y'",
2861                                            env->entity->base.symbol);
2862                                 } else {
2863                                         warningf(HERE, "excess elements in struct initializer");
2864                                 }
2865                         }
2866                 }
2867
2868 error_parse_next:
2869                 if (token.type == '}') {
2870                         break;
2871                 }
2872                 expect(',', end_error);
2873                 if (token.type == '}') {
2874                         break;
2875                 }
2876
2877                 if (type != NULL) {
2878                         /* advance to the next declaration if we are not at the end */
2879                         advance_current_object(path, top_path_level);
2880                         orig_type = path->top_type;
2881                         if (orig_type != NULL)
2882                                 type = skip_typeref(orig_type);
2883                         else
2884                                 type = NULL;
2885                 }
2886         }
2887
2888         size_t len  = ARR_LEN(initializers);
2889         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2890         initializer_t *result = allocate_ast_zero(size);
2891         result->kind          = INITIALIZER_LIST;
2892         result->list.len      = len;
2893         memcpy(&result->list.initializers, initializers,
2894                len * sizeof(initializers[0]));
2895
2896         DEL_ARR_F(initializers);
2897         ascend_to(path, top_path_level+1);
2898
2899         return result;
2900
2901 end_error:
2902         skip_initializers();
2903         DEL_ARR_F(initializers);
2904         ascend_to(path, top_path_level+1);
2905         return NULL;
2906 }
2907
2908 /**
2909  * Parses an initializer. Parsers either a compound literal
2910  * (env->declaration == NULL) or an initializer of a declaration.
2911  */
2912 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2913 {
2914         type_t        *type   = skip_typeref(env->type);
2915         initializer_t *result = NULL;
2916         size_t         max_index;
2917
2918         if (is_type_scalar(type)) {
2919                 result = parse_scalar_initializer(type, env->must_be_constant);
2920         } else if (token.type == '{') {
2921                 eat('{');
2922
2923                 type_path_t path;
2924                 memset(&path, 0, sizeof(path));
2925                 path.top_type = env->type;
2926                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2927
2928                 descend_into_subtype(&path);
2929
2930                 add_anchor_token('}');
2931                 result = parse_sub_initializer(&path, env->type, 1, env);
2932                 rem_anchor_token('}');
2933
2934                 max_index = path.max_index;
2935                 DEL_ARR_F(path.path);
2936
2937                 expect('}', end_error);
2938         } else {
2939                 /* parse_scalar_initializer() also works in this case: we simply
2940                  * have an expression without {} around it */
2941                 result = parse_scalar_initializer(type, env->must_be_constant);
2942         }
2943
2944         /* § 6.7.8 (22) array initializers for arrays with unknown size determine
2945          * the array type size */
2946         if (is_type_array(type) && type->array.size_expression == NULL
2947                         && result != NULL) {
2948                 size_t size;
2949                 switch (result->kind) {
2950                 case INITIALIZER_LIST:
2951                         size = max_index + 1;
2952                         break;
2953
2954                 case INITIALIZER_STRING:
2955                         size = result->string.string.size;
2956                         break;
2957
2958                 case INITIALIZER_WIDE_STRING:
2959                         size = result->wide_string.string.size;
2960                         break;
2961
2962                 case INITIALIZER_DESIGNATOR:
2963                 case INITIALIZER_VALUE:
2964                         /* can happen for parse errors */
2965                         size = 0;
2966                         break;
2967
2968                 default:
2969                         internal_errorf(HERE, "invalid initializer type");
2970                 }
2971
2972                 expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2973                 cnst->base.type          = type_size_t;
2974                 cnst->conste.v.int_value = size;
2975
2976                 type_t *new_type = duplicate_type(type);
2977
2978                 new_type->array.size_expression   = cnst;
2979                 new_type->array.size_constant     = true;
2980                 new_type->array.has_implicit_size = true;
2981                 new_type->array.size              = size;
2982                 env->type = new_type;
2983         }
2984
2985         return result;
2986 end_error:
2987         return NULL;
2988 }
2989
2990 static void append_entity(scope_t *scope, entity_t *entity)
2991 {
2992         if (scope->last_entity != NULL) {
2993                 scope->last_entity->base.next = entity;
2994         } else {
2995                 scope->entities = entity;
2996         }
2997         scope->last_entity = entity;
2998 }
2999
3000
3001 static compound_t *parse_compound_type_specifier(bool is_struct)
3002 {
3003         gnu_attribute_t  *attributes = NULL;
3004         decl_modifiers_t  modifiers  = 0;
3005         if (is_struct) {
3006                 eat(T_struct);
3007         } else {
3008                 eat(T_union);
3009         }
3010
3011         symbol_t   *symbol   = NULL;
3012         compound_t *compound = NULL;
3013
3014         if (token.type == T___attribute__) {
3015                 modifiers |= parse_attributes(&attributes);
3016         }
3017
3018         if (token.type == T_IDENTIFIER) {
3019                 symbol = token.v.symbol;
3020                 next_token();
3021
3022                 namespace_tag_t const namespc =
3023                         is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION;
3024                 entity_t *entity = get_entity(symbol, namespc);
3025                 if (entity != NULL) {
3026                         assert(entity->kind == (is_struct ? ENTITY_STRUCT : ENTITY_UNION));
3027                         compound = &entity->compound;
3028                         if (compound->base.parent_scope != current_scope &&
3029                             (token.type == '{' || token.type == ';')) {
3030                                 /* we're in an inner scope and have a definition. Override
3031                                    existing definition in outer scope */
3032                                 compound = NULL;
3033                         } else if (compound->complete && token.type == '{') {
3034                                 assert(symbol != NULL);
3035                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition %P)",
3036                                        is_struct ? "struct" : "union", symbol,
3037                                        &compound->base.source_position);
3038                                 /* clear members in the hope to avoid further errors */
3039                                 compound->members.entities = NULL;
3040                         }
3041                 }
3042         } else if (token.type != '{') {
3043                 if (is_struct) {
3044                         parse_error_expected("while parsing struct type specifier",
3045                                              T_IDENTIFIER, '{', NULL);
3046                 } else {
3047                         parse_error_expected("while parsing union type specifier",
3048                                              T_IDENTIFIER, '{', NULL);
3049                 }
3050
3051                 return NULL;
3052         }
3053
3054         if (compound == NULL) {
3055                 entity_kind_t  kind   = is_struct ? ENTITY_STRUCT : ENTITY_UNION;
3056                 entity_t      *entity = allocate_entity_zero(kind);
3057                 compound              = &entity->compound;
3058
3059                 compound->base.namespc =
3060                         (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
3061                 compound->base.source_position = token.source_position;
3062                 compound->base.symbol          = symbol;
3063                 compound->base.parent_scope    = current_scope;
3064                 if (symbol != NULL) {
3065                         environment_push(entity);
3066                 }
3067                 append_entity(current_scope, entity);
3068         }
3069
3070         if (token.type == '{') {
3071                 parse_compound_type_entries(compound);
3072                 modifiers |= parse_attributes(&attributes);
3073
3074                 if (symbol == NULL) {
3075                         assert(anonymous_entity == NULL);
3076                         anonymous_entity = (entity_t*)compound;
3077                 }
3078         }
3079
3080         compound->modifiers |= modifiers;
3081         return compound;
3082 }
3083
3084 static void parse_enum_entries(type_t *const enum_type)
3085 {
3086         eat('{');
3087
3088         if (token.type == '}') {
3089                 errorf(HERE, "empty enum not allowed");
3090                 next_token();
3091                 return;
3092         }
3093
3094         add_anchor_token('}');
3095         do {
3096                 if (token.type != T_IDENTIFIER) {
3097                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
3098                         eat_block();
3099                         rem_anchor_token('}');
3100                         return;
3101                 }
3102
3103                 entity_t *entity             = allocate_entity_zero(ENTITY_ENUM_VALUE);
3104                 entity->enum_value.enum_type = enum_type;
3105                 entity->base.symbol          = token.v.symbol;
3106                 entity->base.source_position = token.source_position;
3107                 next_token();
3108
3109                 if (token.type == '=') {
3110                         next_token();
3111                         expression_t *value = parse_constant_expression();
3112
3113                         value = create_implicit_cast(value, enum_type);
3114                         entity->enum_value.value = value;
3115
3116                         /* TODO semantic */
3117                 }
3118
3119                 record_entity(entity, false);
3120
3121                 if (token.type != ',')
3122                         break;
3123                 next_token();
3124         } while (token.type != '}');
3125         rem_anchor_token('}');
3126
3127         expect('}', end_error);
3128
3129 end_error:
3130         ;
3131 }
3132
3133 static type_t *parse_enum_specifier(void)
3134 {
3135         gnu_attribute_t *attributes = NULL;
3136         entity_t        *entity;
3137         symbol_t        *symbol;
3138
3139         eat(T_enum);
3140         if (token.type == T_IDENTIFIER) {
3141                 symbol = token.v.symbol;
3142                 next_token();
3143
3144                 entity = get_entity(symbol, NAMESPACE_ENUM);
3145                 assert(entity == NULL || entity->kind == ENTITY_ENUM);
3146         } else if (token.type != '{') {
3147                 parse_error_expected("while parsing enum type specifier",
3148                                      T_IDENTIFIER, '{', NULL);
3149                 return NULL;
3150         } else {
3151                 entity  = NULL;
3152                 symbol  = NULL;
3153         }
3154
3155         if (entity == NULL) {
3156                 entity                       = allocate_entity_zero(ENTITY_ENUM);
3157                 entity->base.namespc         = NAMESPACE_ENUM;
3158                 entity->base.source_position = token.source_position;
3159                 entity->base.symbol          = symbol;
3160                 entity->base.parent_scope    = current_scope;
3161         }
3162
3163         type_t *const type = allocate_type_zero(TYPE_ENUM);
3164         type->enumt.enume  = &entity->enume;
3165
3166         if (token.type == '{') {
3167                 if (entity->enume.complete) {
3168                         errorf(HERE, "multiple definitions of 'enum %Y' (previous definition %P)",
3169                                symbol, &entity->base.source_position);
3170                 }
3171                 if (symbol != NULL) {
3172                         environment_push(entity);
3173                 }
3174                 append_entity(current_scope, entity);
3175                 entity->enume.complete = true;
3176
3177                 parse_enum_entries(type);
3178                 parse_attributes(&attributes);
3179
3180                 if (symbol == NULL) {
3181                         assert(anonymous_entity == NULL);
3182                         anonymous_entity = entity;
3183                 }
3184         } else if (!entity->enume.complete && !(c_mode & _GNUC)) {
3185                 errorf(HERE, "'enum %Y' used before definition (incomplete enums are a GNU extension)",
3186                        symbol);
3187         }
3188
3189         return type;
3190 }
3191
3192 /**
3193  * if a symbol is a typedef to another type, return true
3194  */
3195 static bool is_typedef_symbol(symbol_t *symbol)
3196 {
3197         const entity_t *const entity = get_entity(symbol, NAMESPACE_NORMAL);
3198         return entity != NULL && entity->kind == ENTITY_TYPEDEF;
3199 }
3200
3201 static type_t *parse_typeof(void)
3202 {
3203         eat(T___typeof__);
3204
3205         type_t *type;
3206
3207         expect('(', end_error);
3208         add_anchor_token(')');
3209
3210         expression_t *expression  = NULL;
3211
3212         bool old_type_prop     = in_type_prop;
3213         bool old_gcc_extension = in_gcc_extension;
3214         in_type_prop           = true;
3215
3216         while (token.type == T___extension__) {
3217                 /* This can be a prefix to a typename or an expression. */
3218                 next_token();
3219                 in_gcc_extension = true;
3220         }
3221         switch (token.type) {
3222         case T_IDENTIFIER:
3223                 if (is_typedef_symbol(token.v.symbol)) {
3224                         type = parse_typename();
3225                 } else {
3226                         expression = parse_expression();
3227                         type       = expression->base.type;
3228                 }
3229                 break;
3230
3231         TYPENAME_START
3232                 type = parse_typename();
3233                 break;
3234
3235         default:
3236                 expression = parse_expression();
3237                 type       = expression->base.type;
3238                 break;
3239         }
3240         in_type_prop     = old_type_prop;
3241         in_gcc_extension = old_gcc_extension;
3242
3243         rem_anchor_token(')');
3244         expect(')', end_error);
3245
3246         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF);
3247         typeof_type->typeoft.expression  = expression;
3248         typeof_type->typeoft.typeof_type = type;
3249
3250         return typeof_type;
3251 end_error:
3252         return NULL;
3253 }
3254
3255 typedef enum specifiers_t {
3256         SPECIFIER_SIGNED    = 1 << 0,
3257         SPECIFIER_UNSIGNED  = 1 << 1,
3258         SPECIFIER_LONG      = 1 << 2,
3259         SPECIFIER_INT       = 1 << 3,
3260         SPECIFIER_DOUBLE    = 1 << 4,
3261         SPECIFIER_CHAR      = 1 << 5,
3262         SPECIFIER_SHORT     = 1 << 6,
3263         SPECIFIER_LONG_LONG = 1 << 7,
3264         SPECIFIER_FLOAT     = 1 << 8,
3265         SPECIFIER_BOOL      = 1 << 9,
3266         SPECIFIER_VOID      = 1 << 10,
3267         SPECIFIER_INT8      = 1 << 11,
3268         SPECIFIER_INT16     = 1 << 12,
3269         SPECIFIER_INT32     = 1 << 13,
3270         SPECIFIER_INT64     = 1 << 14,
3271         SPECIFIER_INT128    = 1 << 15,
3272         SPECIFIER_COMPLEX   = 1 << 16,
3273         SPECIFIER_IMAGINARY = 1 << 17,
3274 } specifiers_t;
3275
3276 static type_t *create_builtin_type(symbol_t *const symbol,
3277                                    type_t *const real_type)
3278 {
3279         type_t *type            = allocate_type_zero(TYPE_BUILTIN);
3280         type->builtin.symbol    = symbol;
3281         type->builtin.real_type = real_type;
3282
3283         type_t *result = typehash_insert(type);
3284         if (type != result) {
3285                 free_type(type);
3286         }
3287
3288         return result;
3289 }
3290
3291 static type_t *get_typedef_type(symbol_t *symbol)
3292 {
3293         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
3294         if (entity == NULL || entity->kind != ENTITY_TYPEDEF)
3295                 return NULL;
3296
3297         type_t *type            = allocate_type_zero(TYPE_TYPEDEF);
3298         type->typedeft.typedefe = &entity->typedefe;
3299
3300         return type;
3301 }
3302
3303 /**
3304  * check for the allowed MS alignment values.
3305  */
3306 static bool check_alignment_value(long long intvalue)
3307 {
3308         if (intvalue < 1 || intvalue > 8192) {
3309                 errorf(HERE, "illegal alignment value");
3310                 return false;
3311         }
3312         unsigned v = (unsigned)intvalue;
3313         for (unsigned i = 1; i <= 8192; i += i) {
3314                 if (i == v)
3315                         return true;
3316         }
3317         errorf(HERE, "alignment must be power of two");
3318         return false;
3319 }
3320
3321 #define DET_MOD(name, tag) do { \
3322         if (*modifiers & tag && warning.other) warningf(HERE, #name " used more than once"); \
3323         *modifiers |= tag; \
3324 } while (0)
3325
3326 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
3327 {
3328         decl_modifiers_t *modifiers = &specifiers->modifiers;
3329
3330         while (true) {
3331                 if (token.type == T_restrict) {
3332                         next_token();
3333                         DET_MOD(restrict, DM_RESTRICT);
3334                         goto end_loop;
3335                 } else if (token.type != T_IDENTIFIER)
3336                         break;
3337                 symbol_t *symbol = token.v.symbol;
3338                 if (symbol == sym_align) {
3339                         next_token();
3340                         expect('(', end_error);
3341                         if (token.type != T_INTEGER)
3342                                 goto end_error;
3343                         if (check_alignment_value(token.v.intvalue)) {
3344                                 if (specifiers->alignment != 0 && warning.other)
3345                                         warningf(HERE, "align used more than once");
3346                                 specifiers->alignment = (unsigned char)token.v.intvalue;
3347                         }
3348                         next_token();
3349                         expect(')', end_error);
3350                 } else if (symbol == sym_allocate) {
3351                         next_token();
3352                         expect('(', end_error);
3353                         if (token.type != T_IDENTIFIER)
3354                                 goto end_error;
3355                         (void)token.v.symbol;
3356                         expect(')', end_error);
3357                 } else if (symbol == sym_dllimport) {
3358                         next_token();
3359                         DET_MOD(dllimport, DM_DLLIMPORT);
3360                 } else if (symbol == sym_dllexport) {
3361                         next_token();
3362                         DET_MOD(dllexport, DM_DLLEXPORT);
3363                 } else if (symbol == sym_thread) {
3364                         next_token();
3365                         DET_MOD(thread, DM_THREAD);
3366                 } else if (symbol == sym_naked) {
3367                         next_token();
3368                         DET_MOD(naked, DM_NAKED);
3369                 } else if (symbol == sym_noinline) {
3370                         next_token();
3371                         DET_MOD(noinline, DM_NOINLINE);
3372                 } else if (symbol == sym_noreturn) {
3373                         next_token();
3374                         DET_MOD(noreturn, DM_NORETURN);
3375                 } else if (symbol == sym_nothrow) {
3376                         next_token();
3377                         DET_MOD(nothrow, DM_NOTHROW);
3378                 } else if (symbol == sym_novtable) {
3379                         next_token();
3380                         DET_MOD(novtable, DM_NOVTABLE);
3381                 } else if (symbol == sym_property) {
3382                         next_token();
3383                         expect('(', end_error);
3384                         for (;;) {
3385                                 bool is_get = false;
3386                                 if (token.type != T_IDENTIFIER)
3387                                         goto end_error;
3388                                 if (token.v.symbol == sym_get) {
3389                                         is_get = true;
3390                                 } else if (token.v.symbol == sym_put) {
3391                                 } else {
3392                                         errorf(HERE, "Bad property name '%Y'", token.v.symbol);
3393                                         goto end_error;
3394                                 }
3395                                 next_token();
3396                                 expect('=', end_error);
3397                                 if (token.type != T_IDENTIFIER)
3398                                         goto end_error;
3399                                 if (is_get) {
3400                                         if (specifiers->get_property_sym != NULL) {
3401                                                 errorf(HERE, "get property name already specified");
3402                                         } else {
3403                                                 specifiers->get_property_sym = token.v.symbol;
3404                                         }
3405                                 } else {
3406                                         if (specifiers->put_property_sym != NULL) {
3407                                                 errorf(HERE, "put property name already specified");
3408                                         } else {
3409                                                 specifiers->put_property_sym = token.v.symbol;
3410                                         }
3411                                 }
3412                                 next_token();
3413                                 if (token.type == ',') {
3414                                         next_token();
3415                                         continue;
3416                                 }
3417                                 break;
3418                         }
3419                         expect(')', end_error);
3420                 } else if (symbol == sym_selectany) {
3421                         next_token();
3422                         DET_MOD(selectany, DM_SELECTANY);
3423                 } else if (symbol == sym_uuid) {
3424                         next_token();
3425                         expect('(', end_error);
3426                         if (token.type != T_STRING_LITERAL)
3427                                 goto end_error;
3428                         next_token();
3429                         expect(')', end_error);
3430                 } else if (symbol == sym_deprecated) {
3431                         next_token();
3432                         if (specifiers->deprecated != 0 && warning.other)
3433                                 warningf(HERE, "deprecated used more than once");
3434                         specifiers->deprecated = true;
3435                         if (token.type == '(') {
3436                                 next_token();
3437                                 if (token.type == T_STRING_LITERAL) {
3438                                         specifiers->deprecated_string = token.v.string.begin;
3439                                         next_token();
3440                                 } else {
3441                                         errorf(HERE, "string literal expected");
3442                                 }
3443                                 expect(')', end_error);
3444                         }
3445                 } else if (symbol == sym_noalias) {
3446                         next_token();
3447                         DET_MOD(noalias, DM_NOALIAS);
3448                 } else {
3449                         if (warning.other)
3450                                 warningf(HERE, "Unknown modifier '%Y' ignored", token.v.symbol);
3451                         next_token();
3452                         if (token.type == '(')
3453                                 skip_until(')');
3454                 }
3455 end_loop:
3456                 if (token.type == ',')
3457                         next_token();
3458         }
3459 end_error:
3460         return;
3461 }
3462
3463 static entity_t *create_error_entity(symbol_t *symbol, entity_kind_tag_t kind)
3464 {
3465         entity_t *entity             = allocate_entity_zero(kind);
3466         entity->base.source_position = *HERE;
3467         entity->base.symbol          = symbol;
3468         if (is_declaration(entity)) {
3469                 entity->declaration.type     = type_error_type;
3470                 entity->declaration.implicit = true;
3471         } else if (kind == ENTITY_TYPEDEF) {
3472                 entity->typedefe.type    = type_error_type;
3473                 entity->typedefe.builtin = true;
3474         }
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 void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
3614 {
3615         type_t            *type              = NULL;
3616         type_qualifiers_t  qualifiers        = TYPE_QUALIFIER_NONE;
3617         type_modifiers_t   modifiers         = TYPE_MODIFIER_NONE;
3618         unsigned           type_specifiers   = 0;
3619         bool               newtype           = false;
3620         bool               saw_error         = false;
3621         bool               old_gcc_extension = in_gcc_extension;
3622
3623         specifiers->source_position = token.source_position;
3624
3625         while (true) {
3626                 specifiers->modifiers
3627                         |= parse_attributes(&specifiers->gnu_attributes);
3628                 if (specifiers->modifiers & DM_TRANSPARENT_UNION)
3629                         modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3630
3631                 switch (token.type) {
3632                 /* storage class */
3633 #define MATCH_STORAGE_CLASS(token, class)                                  \
3634                 case token:                                                        \
3635                         if (specifiers->storage_class != STORAGE_CLASS_NONE) {         \
3636                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3637                         }                                                              \
3638                         specifiers->storage_class = class;                             \
3639                         if (specifiers->thread_local)                                  \
3640                                 goto check_thread_storage_class;                           \
3641                         next_token();                                                  \
3642                         break;
3643
3644                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3645                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3646                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3647                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3648                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3649
3650                 case T__declspec:
3651                         next_token();
3652                         expect('(', end_error);
3653                         add_anchor_token(')');
3654                         parse_microsoft_extended_decl_modifier(specifiers);
3655                         rem_anchor_token(')');
3656                         expect(')', end_error);
3657                         break;
3658
3659                 case T___thread:
3660                         if (specifiers->thread_local) {
3661                                 errorf(HERE, "duplicate '__thread'");
3662                         } else {
3663                                 specifiers->thread_local = true;
3664 check_thread_storage_class:
3665                                 switch (specifiers->storage_class) {
3666                                         case STORAGE_CLASS_EXTERN:
3667                                         case STORAGE_CLASS_NONE:
3668                                         case STORAGE_CLASS_STATIC:
3669                                                 break;
3670
3671                                                 char const* wrong;
3672                                         case STORAGE_CLASS_AUTO:     wrong = "auto";     goto wrong_thread_stoarge_class;
3673                                         case STORAGE_CLASS_REGISTER: wrong = "register"; goto wrong_thread_stoarge_class;
3674                                         case STORAGE_CLASS_TYPEDEF:  wrong = "typedef";  goto wrong_thread_stoarge_class;
3675 wrong_thread_stoarge_class:
3676                                                 errorf(HERE, "'__thread' used with '%s'", wrong);
3677                                                 break;
3678                                 }
3679                         }
3680                         next_token();
3681                         break;
3682
3683                 /* type qualifiers */
3684 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3685                 case token:                                                     \
3686                         qualifiers |= qualifier;                                    \
3687                         next_token();                                               \
3688                         break
3689
3690                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3691                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3692                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3693                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3694                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3695                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3696                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3697                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3698
3699                 case T___extension__:
3700                         next_token();
3701                         in_gcc_extension = true;
3702                         break;
3703
3704                 /* type specifiers */
3705 #define MATCH_SPECIFIER(token, specifier, name)                         \
3706                 case token:                                                     \
3707                         if (type_specifiers & specifier) {                           \
3708                                 errorf(HERE, "multiple " name " type specifiers given"); \
3709                         } else {                                                    \
3710                                 type_specifiers |= specifier;                           \
3711                         }                                                           \
3712                         next_token();                                               \
3713                         break
3714
3715                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3716                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3717                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3718                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3719                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3720                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3721                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3722                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3723                 MATCH_SPECIFIER(T_bool,       SPECIFIER_BOOL,      "bool");
3724                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3725                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3726                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3727                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3728                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3729                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3730                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3731                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3732
3733                 case T__forceinline:
3734                         /* only in microsoft mode */
3735                         specifiers->modifiers |= DM_FORCEINLINE;
3736                         /* FALLTHROUGH */
3737
3738                 case T_inline:
3739                         next_token();
3740                         specifiers->is_inline = true;
3741                         break;
3742
3743                 case T_long:
3744                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3745                                 errorf(HERE, "multiple type specifiers given");
3746                         } else if (type_specifiers & SPECIFIER_LONG) {
3747                                 type_specifiers |= SPECIFIER_LONG_LONG;
3748                         } else {
3749                                 type_specifiers |= SPECIFIER_LONG;
3750                         }
3751                         next_token();
3752                         break;
3753
3754                 case T_struct: {
3755                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT);
3756
3757                         type->compound.compound = parse_compound_type_specifier(true);
3758                         finish_struct_type(&type->compound);
3759                         break;
3760                 }
3761                 case T_union: {
3762                         type = allocate_type_zero(TYPE_COMPOUND_UNION);
3763                         type->compound.compound = parse_compound_type_specifier(false);
3764                         if (type->compound.compound->modifiers & DM_TRANSPARENT_UNION)
3765                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3766                         finish_union_type(&type->compound);
3767                         break;
3768                 }
3769                 case T_enum:
3770                         type = parse_enum_specifier();
3771                         break;
3772                 case T___typeof__:
3773                         type = parse_typeof();
3774                         break;
3775                 case T___builtin_va_list:
3776                         type = duplicate_type(type_valist);
3777                         next_token();
3778                         break;
3779
3780                 case T_IDENTIFIER: {
3781                         /* only parse identifier if we haven't found a type yet */
3782                         if (type != NULL || type_specifiers != 0) {
3783                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
3784                                  * declaration, so it doesn't generate errors about expecting '(' or
3785                                  * '{' later on. */
3786                                 switch (look_ahead(1)->type) {
3787                                         STORAGE_CLASSES
3788                                         TYPE_SPECIFIERS
3789                                         case T_const:
3790                                         case T_restrict:
3791                                         case T_volatile:
3792                                         case T_inline:
3793                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
3794                                         case T_IDENTIFIER:
3795                                         case '&':
3796                                         case '*':
3797                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
3798                                                 next_token();
3799                                                 continue;
3800
3801                                         default:
3802                                                 goto finish_specifiers;
3803                                 }
3804                         }
3805
3806                         type_t *const typedef_type = get_typedef_type(token.v.symbol);
3807                         if (typedef_type == NULL) {
3808                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3809                                  * declaration, so it doesn't generate 'implicit int' followed by more
3810                                  * errors later on. */
3811                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3812                                 switch (la1_type) {
3813                                         DECLARATION_START
3814                                         case T_IDENTIFIER:
3815                                         case '&':
3816                                         case '*': {
3817                                                 errorf(HERE, "%K does not name a type", &token);
3818
3819                                                 entity_t *entity =
3820                                                         create_error_entity(token.v.symbol, ENTITY_TYPEDEF);
3821
3822                                                 type = allocate_type_zero(TYPE_TYPEDEF);
3823                                                 type->typedeft.typedefe = &entity->typedefe;
3824
3825                                                 next_token();
3826                                                 saw_error = true;
3827                                                 if (la1_type == '&' || la1_type == '*')
3828                                                         goto finish_specifiers;
3829                                                 continue;
3830                                         }
3831
3832                                         default:
3833                                                 goto finish_specifiers;
3834                                 }
3835                         }
3836
3837                         next_token();
3838                         type = typedef_type;
3839                         break;
3840                 }
3841
3842                 /* function specifier */
3843                 default:
3844                         goto finish_specifiers;
3845                 }
3846         }
3847
3848 finish_specifiers:
3849         in_gcc_extension = old_gcc_extension;
3850
3851         if (type == NULL || (saw_error && type_specifiers != 0)) {
3852                 atomic_type_kind_t atomic_type;
3853
3854                 /* match valid basic types */
3855                 switch (type_specifiers) {
3856                 case SPECIFIER_VOID:
3857                         atomic_type = ATOMIC_TYPE_VOID;
3858                         break;
3859                 case SPECIFIER_CHAR:
3860                         atomic_type = ATOMIC_TYPE_CHAR;
3861                         break;
3862                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3863                         atomic_type = ATOMIC_TYPE_SCHAR;
3864                         break;
3865                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3866                         atomic_type = ATOMIC_TYPE_UCHAR;
3867                         break;
3868                 case SPECIFIER_SHORT:
3869                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3870                 case SPECIFIER_SHORT | SPECIFIER_INT:
3871                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3872                         atomic_type = ATOMIC_TYPE_SHORT;
3873                         break;
3874                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3875                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3876                         atomic_type = ATOMIC_TYPE_USHORT;
3877                         break;
3878                 case SPECIFIER_INT:
3879                 case SPECIFIER_SIGNED:
3880                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3881                         atomic_type = ATOMIC_TYPE_INT;
3882                         break;
3883                 case SPECIFIER_UNSIGNED:
3884                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3885                         atomic_type = ATOMIC_TYPE_UINT;
3886                         break;
3887                 case SPECIFIER_LONG:
3888                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3889                 case SPECIFIER_LONG | SPECIFIER_INT:
3890                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3891                         atomic_type = ATOMIC_TYPE_LONG;
3892                         break;
3893                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3894                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3895                         atomic_type = ATOMIC_TYPE_ULONG;
3896                         break;
3897
3898                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3899                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3900                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3901                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3902                         | SPECIFIER_INT:
3903                         atomic_type = ATOMIC_TYPE_LONGLONG;
3904                         goto warn_about_long_long;
3905
3906                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3907                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3908                         | SPECIFIER_INT:
3909                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3910 warn_about_long_long:
3911                         if (warning.long_long) {
3912                                 warningf(&specifiers->source_position,
3913                                          "ISO C90 does not support 'long long'");
3914                         }
3915                         break;
3916
3917                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3918                         atomic_type = unsigned_int8_type_kind;
3919                         break;
3920
3921                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3922                         atomic_type = unsigned_int16_type_kind;
3923                         break;
3924
3925                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3926                         atomic_type = unsigned_int32_type_kind;
3927                         break;
3928
3929                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3930                         atomic_type = unsigned_int64_type_kind;
3931                         break;
3932
3933                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3934                         atomic_type = unsigned_int128_type_kind;
3935                         break;
3936
3937                 case SPECIFIER_INT8:
3938                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3939                         atomic_type = int8_type_kind;
3940                         break;
3941
3942                 case SPECIFIER_INT16:
3943                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3944                         atomic_type = int16_type_kind;
3945                         break;
3946
3947                 case SPECIFIER_INT32:
3948                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3949                         atomic_type = int32_type_kind;
3950                         break;
3951
3952                 case SPECIFIER_INT64:
3953                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3954                         atomic_type = int64_type_kind;
3955                         break;
3956
3957                 case SPECIFIER_INT128:
3958                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3959                         atomic_type = int128_type_kind;
3960                         break;
3961
3962                 case SPECIFIER_FLOAT:
3963                         atomic_type = ATOMIC_TYPE_FLOAT;
3964                         break;
3965                 case SPECIFIER_DOUBLE:
3966                         atomic_type = ATOMIC_TYPE_DOUBLE;
3967                         break;
3968                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3969                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3970                         break;
3971                 case SPECIFIER_BOOL:
3972                         atomic_type = ATOMIC_TYPE_BOOL;
3973                         break;
3974                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3975                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3976                         atomic_type = ATOMIC_TYPE_FLOAT;
3977                         break;
3978                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3979                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3980                         atomic_type = ATOMIC_TYPE_DOUBLE;
3981                         break;
3982                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3983                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3984                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3985                         break;
3986                 default:
3987                         /* invalid specifier combination, give an error message */
3988                         if (type_specifiers == 0) {
3989                                 if (saw_error)
3990                                         goto end_error;
3991
3992                                 /* ISO/IEC 14882:1998(E) §C.1.5:4 */
3993                                 if (!(c_mode & _CXX) && !strict_mode) {
3994                                         if (warning.implicit_int) {
3995                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
3996                                         }
3997                                         atomic_type = ATOMIC_TYPE_INT;
3998                                         break;
3999                                 } else {
4000                                         errorf(HERE, "no type specifiers given in declaration");
4001                                 }
4002                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
4003                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
4004                                 errorf(HERE, "signed and unsigned specifiers given");
4005                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
4006                                 errorf(HERE, "only integer types can be signed or unsigned");
4007                         } else {
4008                                 errorf(HERE, "multiple datatypes in declaration");
4009                         }
4010                         goto end_error;
4011                 }
4012
4013                 if (type_specifiers & SPECIFIER_COMPLEX) {
4014                         type                = allocate_type_zero(TYPE_COMPLEX);
4015                         type->complex.akind = atomic_type;
4016                 } else if (type_specifiers & SPECIFIER_IMAGINARY) {
4017                         type                  = allocate_type_zero(TYPE_IMAGINARY);
4018                         type->imaginary.akind = atomic_type;
4019                 } else {
4020                         type               = allocate_type_zero(TYPE_ATOMIC);
4021                         type->atomic.akind = atomic_type;
4022                 }
4023                 newtype = true;
4024         } else if (type_specifiers != 0) {
4025                 errorf(HERE, "multiple datatypes in declaration");
4026         }
4027
4028         /* FIXME: check type qualifiers here */
4029
4030         type->base.qualifiers = qualifiers;
4031         type->base.modifiers  = modifiers;
4032
4033         type_t *result = typehash_insert(type);
4034         if (newtype && result != type) {
4035                 free_type(type);
4036         }
4037
4038         specifiers->type = result;
4039         return;
4040
4041 end_error:
4042         specifiers->type = type_error_type;
4043         return;
4044 }
4045
4046 static type_qualifiers_t parse_type_qualifiers(void)
4047 {
4048         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
4049
4050         while (true) {
4051                 switch (token.type) {
4052                 /* type qualifiers */
4053                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
4054                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
4055                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
4056                 /* microsoft extended type modifiers */
4057                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
4058                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
4059                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
4060                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
4061                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
4062
4063                 default:
4064                         return qualifiers;
4065                 }
4066         }
4067 }
4068
4069 /**
4070  * Parses an K&R identifier list
4071  */
4072 static void parse_identifier_list(scope_t *scope)
4073 {
4074         do {
4075                 entity_t *entity = allocate_entity_zero(ENTITY_PARAMETER);
4076                 entity->base.source_position = token.source_position;
4077                 entity->base.namespc         = NAMESPACE_NORMAL;
4078                 entity->base.symbol          = token.v.symbol;
4079                 /* a K&R parameter has no type, yet */
4080                 next_token();
4081
4082                 if (scope != NULL)
4083                         append_entity(scope, entity);
4084
4085                 if (token.type != ',') {
4086                         break;
4087                 }
4088                 next_token();
4089         } while (token.type == T_IDENTIFIER);
4090 }
4091
4092 static entity_t *parse_parameter(void)
4093 {
4094         declaration_specifiers_t specifiers;
4095         memset(&specifiers, 0, sizeof(specifiers));
4096
4097         parse_declaration_specifiers(&specifiers);
4098
4099         entity_t *entity = parse_declarator(&specifiers,
4100                         DECL_MAY_BE_ABSTRACT | DECL_IS_PARAMETER);
4101         anonymous_entity = NULL;
4102         return entity;
4103 }
4104
4105 static void semantic_parameter_incomplete(const entity_t *entity)
4106 {
4107         assert(entity->kind == ENTITY_PARAMETER);
4108
4109         /* §6.7.5.3:4  After adjustment, the parameters in a parameter type
4110          *             list in a function declarator that is part of a
4111          *             definition of that function shall not have
4112          *             incomplete type. */
4113         type_t *type = skip_typeref(entity->declaration.type);
4114         if (is_type_incomplete(type)) {
4115                 errorf(&entity->base.source_position,
4116                        "parameter '%Y' has incomplete type '%T'", entity->base.symbol,
4117                        entity->declaration.type);
4118         }
4119 }
4120
4121 /**
4122  * Parses function type parameters (and optionally creates variable_t entities
4123  * for them in a scope)
4124  */
4125 static void parse_parameters(function_type_t *type, scope_t *scope)
4126 {
4127         eat('(');
4128         add_anchor_token(')');
4129         int saved_comma_state = save_and_reset_anchor_state(',');
4130
4131         if (token.type == T_IDENTIFIER &&
4132             !is_typedef_symbol(token.v.symbol)) {
4133                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
4134                 if (la1_type == ',' || la1_type == ')') {
4135                         type->kr_style_parameters    = true;
4136                         type->unspecified_parameters = true;
4137                         parse_identifier_list(scope);
4138                         goto parameters_finished;
4139                 }
4140         }
4141
4142         if (token.type == ')') {
4143                 /* ISO/IEC 14882:1998(E) §C.1.6:1 */
4144                 if (!(c_mode & _CXX))
4145                         type->unspecified_parameters = true;
4146                 goto parameters_finished;
4147         }
4148
4149         function_parameter_t *parameter;
4150         function_parameter_t *last_parameter = NULL;
4151
4152         while (true) {
4153                 switch (token.type) {
4154                 case T_DOTDOTDOT:
4155                         next_token();
4156                         type->variadic = true;
4157                         goto parameters_finished;
4158
4159                 case T_IDENTIFIER:
4160                 case T___extension__:
4161                 DECLARATION_START
4162                 {
4163                         entity_t *entity = parse_parameter();
4164                         if (entity->kind == ENTITY_TYPEDEF) {
4165                                 errorf(&entity->base.source_position,
4166                                        "typedef not allowed as function parameter");
4167                                 break;
4168                         }
4169                         assert(is_declaration(entity));
4170
4171                         /* func(void) is not a parameter */
4172                         if (last_parameter == NULL
4173                                         && token.type == ')'
4174                                         && entity->base.symbol == NULL
4175                                         && skip_typeref(entity->declaration.type) == type_void) {
4176                                 goto parameters_finished;
4177                         }
4178                         semantic_parameter_incomplete(entity);
4179
4180                         parameter = obstack_alloc(type_obst, sizeof(parameter[0]));
4181                         memset(parameter, 0, sizeof(parameter[0]));
4182                         parameter->type = entity->declaration.type;
4183
4184                         if (scope != NULL) {
4185                                 append_entity(scope, entity);
4186                         }
4187
4188                         if (last_parameter != NULL) {
4189                                 last_parameter->next = parameter;
4190                         } else {
4191                                 type->parameters = parameter;
4192                         }
4193                         last_parameter   = parameter;
4194                         break;
4195                 }
4196
4197                 default:
4198                         goto parameters_finished;
4199                 }
4200                 if (token.type != ',') {
4201                         goto parameters_finished;
4202                 }
4203                 next_token();
4204         }
4205
4206
4207 parameters_finished:
4208         rem_anchor_token(')');
4209         expect(')', end_error);
4210
4211 end_error:
4212         restore_anchor_state(',', saved_comma_state);
4213 }
4214
4215 typedef enum construct_type_kind_t {
4216         CONSTRUCT_INVALID,
4217         CONSTRUCT_POINTER,
4218         CONSTRUCT_REFERENCE,
4219         CONSTRUCT_FUNCTION,
4220         CONSTRUCT_ARRAY
4221 } construct_type_kind_t;
4222
4223 typedef struct construct_type_t construct_type_t;
4224 struct construct_type_t {
4225         construct_type_kind_t  kind;
4226         construct_type_t      *next;
4227 };
4228
4229 typedef struct parsed_pointer_t parsed_pointer_t;
4230 struct parsed_pointer_t {
4231         construct_type_t  construct_type;
4232         type_qualifiers_t type_qualifiers;
4233         variable_t        *base_variable;  /**< MS __based extension. */
4234 };
4235
4236 typedef struct parsed_reference_t parsed_reference_t;
4237 struct parsed_reference_t {
4238         construct_type_t construct_type;
4239 };
4240
4241 typedef struct construct_function_type_t construct_function_type_t;
4242 struct construct_function_type_t {
4243         construct_type_t  construct_type;
4244         type_t           *function_type;
4245 };
4246
4247 typedef struct parsed_array_t parsed_array_t;
4248 struct parsed_array_t {
4249         construct_type_t  construct_type;
4250         type_qualifiers_t type_qualifiers;
4251         bool              is_static;
4252         bool              is_variable;
4253         expression_t     *size;
4254 };
4255
4256 typedef struct construct_base_type_t construct_base_type_t;
4257 struct construct_base_type_t {
4258         construct_type_t  construct_type;
4259         type_t           *type;
4260 };
4261
4262 static construct_type_t *parse_pointer_declarator(variable_t *base_variable)
4263 {
4264         eat('*');
4265
4266         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
4267         memset(pointer, 0, sizeof(pointer[0]));
4268         pointer->construct_type.kind = CONSTRUCT_POINTER;
4269         pointer->type_qualifiers     = parse_type_qualifiers();
4270         pointer->base_variable       = base_variable;
4271
4272         return &pointer->construct_type;
4273 }
4274
4275 static construct_type_t *parse_reference_declarator(void)
4276 {
4277         eat('&');
4278
4279         parsed_reference_t *reference = obstack_alloc(&temp_obst, sizeof(reference[0]));
4280         memset(reference, 0, sizeof(reference[0]));
4281         reference->construct_type.kind = CONSTRUCT_REFERENCE;
4282
4283         return (construct_type_t*)reference;
4284 }
4285
4286 static construct_type_t *parse_array_declarator(void)
4287 {
4288         eat('[');
4289         add_anchor_token(']');
4290
4291         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
4292         memset(array, 0, sizeof(array[0]));
4293         array->construct_type.kind = CONSTRUCT_ARRAY;
4294
4295         if (token.type == T_static) {
4296                 array->is_static = true;
4297                 next_token();
4298         }
4299
4300         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
4301         if (type_qualifiers != 0) {
4302                 if (token.type == T_static) {
4303                         array->is_static = true;
4304                         next_token();
4305                 }
4306         }
4307         array->type_qualifiers = type_qualifiers;
4308
4309         if (token.type == '*' && look_ahead(1)->type == ']') {
4310                 array->is_variable = true;
4311                 next_token();
4312         } else if (token.type != ']') {
4313                 array->size = parse_assignment_expression();
4314         }
4315
4316         rem_anchor_token(']');
4317         expect(']', end_error);
4318
4319 end_error:
4320         return &array->construct_type;
4321 }
4322
4323 static construct_type_t *parse_function_declarator(scope_t *scope,
4324                                                    decl_modifiers_t modifiers)
4325 {
4326         type_t          *type  = allocate_type_zero(TYPE_FUNCTION);
4327         function_type_t *ftype = &type->function;
4328
4329         ftype->linkage = current_linkage;
4330
4331         switch (modifiers & (DM_CDECL | DM_STDCALL | DM_FASTCALL | DM_THISCALL)) {
4332                 case DM_NONE:     break;
4333                 case DM_CDECL:    ftype->calling_convention = CC_CDECL;    break;
4334                 case DM_STDCALL:  ftype->calling_convention = CC_STDCALL;  break;
4335                 case DM_FASTCALL: ftype->calling_convention = CC_FASTCALL; break;
4336                 case DM_THISCALL: ftype->calling_convention = CC_THISCALL; break;
4337
4338                 default:
4339                         errorf(HERE, "multiple calling conventions in declaration");
4340                         break;
4341         }
4342
4343         parse_parameters(ftype, scope);
4344
4345         construct_function_type_t *construct_function_type =
4346                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
4347         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
4348         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
4349         construct_function_type->function_type       = type;
4350
4351         return &construct_function_type->construct_type;
4352 }
4353
4354 typedef struct parse_declarator_env_t {
4355         decl_modifiers_t   modifiers;
4356         symbol_t          *symbol;
4357         source_position_t  source_position;
4358         scope_t            parameters;
4359 } parse_declarator_env_t;
4360
4361 static construct_type_t *parse_inner_declarator(parse_declarator_env_t *env,
4362                 bool may_be_abstract)
4363 {
4364         /* construct a single linked list of construct_type_t's which describe
4365          * how to construct the final declarator type */
4366         construct_type_t *first      = NULL;
4367         construct_type_t *last       = NULL;
4368         gnu_attribute_t  *attributes = NULL;
4369
4370         decl_modifiers_t modifiers = parse_attributes(&attributes);
4371
4372         /* MS __based extension */
4373         based_spec_t base_spec;
4374         base_spec.base_variable = NULL;
4375
4376         for (;;) {
4377                 construct_type_t *type;
4378                 switch (token.type) {
4379                         case '&':
4380                                 if (!(c_mode & _CXX))
4381                                         errorf(HERE, "references are only available for C++");
4382                                 if (base_spec.base_variable != NULL && warning.other) {
4383                                         warningf(&base_spec.source_position,
4384                                                  "__based does not precede a pointer operator, ignored");
4385                                 }
4386                                 type = parse_reference_declarator();
4387                                 /* consumed */
4388                                 base_spec.base_variable = NULL;
4389                                 break;
4390
4391                         case '*':
4392                                 type = parse_pointer_declarator(base_spec.base_variable);
4393                                 /* consumed */
4394                                 base_spec.base_variable = NULL;
4395                                 break;
4396
4397                         case T__based:
4398                                 next_token();
4399                                 expect('(', end_error);
4400                                 add_anchor_token(')');
4401                                 parse_microsoft_based(&base_spec);
4402                                 rem_anchor_token(')');
4403                                 expect(')', end_error);
4404                                 continue;
4405
4406                         default:
4407                                 goto ptr_operator_end;
4408                 }
4409
4410                 if (last == NULL) {
4411                         first = type;
4412                         last  = type;
4413                 } else {
4414                         last->next = type;
4415                         last       = type;
4416                 }
4417
4418                 /* TODO: find out if this is correct */
4419                 modifiers |= parse_attributes(&attributes);
4420         }
4421 ptr_operator_end:
4422         if (base_spec.base_variable != NULL && warning.other) {
4423                 warningf(&base_spec.source_position,
4424                          "__based does not precede a pointer operator, ignored");
4425         }
4426
4427         if (env != NULL) {
4428                 modifiers      |= env->modifiers;
4429                 env->modifiers  = modifiers;
4430         }
4431
4432         construct_type_t *inner_types = NULL;
4433
4434         switch (token.type) {
4435         case T_IDENTIFIER:
4436                 if (env == NULL) {
4437                         errorf(HERE, "no identifier expected in typename");
4438                 } else {
4439                         env->symbol          = token.v.symbol;
4440                         env->source_position = token.source_position;
4441                 }
4442                 next_token();
4443                 break;
4444         case '(':
4445                 /* §6.7.6:2 footnote 126:  Empty parentheses in a type name are
4446                  * interpreted as ``function with no parameter specification'', rather
4447                  * than redundant parentheses around the omitted identifier. */
4448                 if (look_ahead(1)->type != ')') {
4449                         next_token();
4450                         add_anchor_token(')');
4451                         inner_types = parse_inner_declarator(env, may_be_abstract);
4452                         if (inner_types != NULL) {
4453                                 /* All later declarators only modify the return type */
4454                                 env = NULL;
4455                         }
4456                         rem_anchor_token(')');
4457                         expect(')', end_error);
4458                 }
4459                 break;
4460         default:
4461                 if (may_be_abstract)
4462                         break;
4463                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
4464                 eat_until_anchor();
4465                 return NULL;
4466         }
4467
4468         construct_type_t *p = last;
4469
4470         while (true) {
4471                 construct_type_t *type;
4472                 switch (token.type) {
4473                 case '(': {
4474                         scope_t *scope = NULL;
4475                         if (env != NULL)
4476                                 scope = &env->parameters;
4477
4478                         type = parse_function_declarator(scope, modifiers);
4479                         break;
4480                 }
4481                 case '[':
4482                         type = parse_array_declarator();
4483                         break;
4484                 default:
4485                         goto declarator_finished;
4486                 }
4487
4488                 /* insert in the middle of the list (behind p) */
4489                 if (p != NULL) {
4490                         type->next = p->next;
4491                         p->next    = type;
4492                 } else {
4493                         type->next = first;
4494                         first      = type;
4495                 }
4496                 if (last == p) {
4497                         last = type;
4498                 }
4499         }
4500
4501 declarator_finished:
4502         /* append inner_types at the end of the list, we don't to set last anymore
4503          * as it's not needed anymore */
4504         if (last == NULL) {
4505                 assert(first == NULL);
4506                 first = inner_types;
4507         } else {
4508                 last->next = inner_types;
4509         }
4510
4511         return first;
4512 end_error:
4513         return NULL;
4514 }
4515
4516 static void parse_declaration_attributes(entity_t *entity)
4517 {
4518         gnu_attribute_t  *attributes = NULL;
4519         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
4520
4521         if (entity == NULL)
4522                 return;
4523
4524         type_t *type;
4525         if (entity->kind == ENTITY_TYPEDEF) {
4526                 modifiers |= entity->typedefe.modifiers;
4527                 type       = entity->typedefe.type;
4528         } else {
4529                 assert(is_declaration(entity));
4530                 modifiers |= entity->declaration.modifiers;
4531                 type       = entity->declaration.type;
4532         }
4533         if (type == NULL)
4534                 return;
4535
4536         /* handle these strange/stupid mode attributes */
4537         gnu_attribute_t *attribute = attributes;
4538         for ( ; attribute != NULL; attribute = attribute->next) {
4539                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
4540                         continue;
4541
4542                 atomic_type_kind_t  akind = attribute->u.akind;
4543                 if (!is_type_signed(type)) {
4544                         switch (akind) {
4545                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
4546                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
4547                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
4548                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
4549                         default:
4550                                 panic("invalid akind in mode attribute");
4551                         }
4552                 } else {
4553                         switch (akind) {
4554                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_SCHAR; break;
4555                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_SHORT; break;
4556                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_INT; break;
4557                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_LONGLONG; break;
4558                         default:
4559                                 panic("invalid akind in mode attribute");
4560                         }
4561                 }
4562
4563                 type = make_atomic_type(akind, type->base.qualifiers);
4564         }
4565
4566         type_modifiers_t type_modifiers = type->base.modifiers;
4567         if (modifiers & DM_TRANSPARENT_UNION)
4568                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
4569
4570         if (type->base.modifiers != type_modifiers) {
4571                 type_t *copy = duplicate_type(type);
4572                 copy->base.modifiers = type_modifiers;
4573
4574                 type = typehash_insert(copy);
4575                 if (type != copy) {
4576                         obstack_free(type_obst, copy);
4577                 }
4578         }
4579
4580         if (entity->kind == ENTITY_TYPEDEF) {
4581                 entity->typedefe.type      = type;
4582                 entity->typedefe.modifiers = modifiers;
4583         } else {
4584                 entity->declaration.type      = type;
4585                 entity->declaration.modifiers = modifiers;
4586         }
4587 }
4588
4589 static type_t *construct_declarator_type(construct_type_t *construct_list, type_t *type)
4590 {
4591         construct_type_t *iter = construct_list;
4592         for (; iter != NULL; iter = iter->next) {
4593                 switch (iter->kind) {
4594                 case CONSTRUCT_INVALID:
4595                         internal_errorf(HERE, "invalid type construction found");
4596                 case CONSTRUCT_FUNCTION: {
4597                         construct_function_type_t *construct_function_type
4598                                 = (construct_function_type_t*) iter;
4599
4600                         type_t *function_type = construct_function_type->function_type;
4601
4602                         function_type->function.return_type = type;
4603
4604                         type_t *skipped_return_type = skip_typeref(type);
4605                         /* §6.7.5.3(1) */
4606                         if (is_type_function(skipped_return_type)) {
4607                                 errorf(HERE, "function returning function is not allowed");
4608                         } else if (is_type_array(skipped_return_type)) {
4609                                 errorf(HERE, "function returning array is not allowed");
4610                         } else {
4611                                 if (skipped_return_type->base.qualifiers != 0 && warning.other) {
4612                                         warningf(HERE,
4613                                                 "type qualifiers in return type of function type are meaningless");
4614                                 }
4615                         }
4616
4617                         type = function_type;
4618                         break;
4619                 }
4620
4621                 case CONSTRUCT_POINTER: {
4622                         if (is_type_reference(skip_typeref(type)))
4623                                 errorf(HERE, "cannot declare a pointer to reference");
4624
4625                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
4626                         type = make_based_pointer_type(type, parsed_pointer->type_qualifiers, parsed_pointer->base_variable);
4627                         continue;
4628                 }
4629
4630                 case CONSTRUCT_REFERENCE:
4631                         if (is_type_reference(skip_typeref(type)))
4632                                 errorf(HERE, "cannot declare a reference to reference");
4633
4634                         type = make_reference_type(type);
4635                         continue;
4636
4637                 case CONSTRUCT_ARRAY: {
4638                         if (is_type_reference(skip_typeref(type)))
4639                                 errorf(HERE, "cannot declare an array of references");
4640
4641                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
4642                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY);
4643
4644                         expression_t *size_expression = parsed_array->size;
4645                         if (size_expression != NULL) {
4646                                 size_expression
4647                                         = create_implicit_cast(size_expression, type_size_t);
4648                         }
4649
4650                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
4651                         array_type->array.element_type    = type;
4652                         array_type->array.is_static       = parsed_array->is_static;
4653                         array_type->array.is_variable     = parsed_array->is_variable;
4654                         array_type->array.size_expression = size_expression;
4655
4656                         if (size_expression != NULL) {
4657                                 if (is_constant_expression(size_expression)) {
4658                                         array_type->array.size_constant = true;
4659                                         array_type->array.size
4660                                                 = fold_constant(size_expression);
4661                                 } else {
4662                                         array_type->array.is_vla = true;
4663                                 }
4664                         }
4665
4666                         type_t *skipped_type = skip_typeref(type);
4667                         /* §6.7.5.2(1) */
4668                         if (is_type_incomplete(skipped_type)) {
4669                                 errorf(HERE, "array of incomplete type '%T' is not allowed", type);
4670                         } else if (is_type_function(skipped_type)) {
4671                                 errorf(HERE, "array of functions is not allowed");
4672                         }
4673                         type = array_type;
4674                         break;
4675                 }
4676                 }
4677
4678                 type_t *hashed_type = typehash_insert(type);
4679                 if (hashed_type != type) {
4680                         /* the function type was constructed earlier freeing it here will
4681                          * destroy other types... */
4682                         if (iter->kind != CONSTRUCT_FUNCTION) {
4683                                 free_type(type);
4684                         }
4685                         type = hashed_type;
4686                 }
4687         }
4688
4689         return type;
4690 }
4691
4692 static type_t *automatic_type_conversion(type_t *orig_type);
4693
4694 static type_t *semantic_parameter(const source_position_t *pos,
4695                                   type_t *type,
4696                                   const declaration_specifiers_t *specifiers,
4697                                   symbol_t *symbol)
4698 {
4699         /* §6.7.5.3:7  A declaration of a parameter as ``array of type''
4700          *             shall be adjusted to ``qualified pointer to type'',
4701          *             [...]
4702          * §6.7.5.3:8  A declaration of a parameter as ``function returning
4703          *             type'' shall be adjusted to ``pointer to function
4704          *             returning type'', as in 6.3.2.1. */
4705         type = automatic_type_conversion(type);
4706
4707         if (specifiers->is_inline && is_type_valid(type)) {
4708                 errorf(pos, "parameter '%Y' declared 'inline'", symbol);
4709         }
4710
4711         /* §6.9.1:6  The declarations in the declaration list shall contain
4712          *           no storage-class specifier other than register and no
4713          *           initializations. */
4714         if (specifiers->thread_local || (
4715                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4716                         specifiers->storage_class != STORAGE_CLASS_REGISTER)
4717            ) {
4718                 errorf(pos, "invalid storage class for parameter '%Y'", symbol);
4719         }
4720
4721         /* delay test for incomplete type, because we might have (void)
4722          * which is legal but incomplete... */
4723
4724         return type;
4725 }
4726
4727 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
4728                                   declarator_flags_t flags)
4729 {
4730         parse_declarator_env_t env;
4731         memset(&env, 0, sizeof(env));
4732         env.modifiers = specifiers->modifiers;
4733
4734         construct_type_t *construct_type =
4735                 parse_inner_declarator(&env, (flags & DECL_MAY_BE_ABSTRACT) != 0);
4736         type_t           *orig_type      =
4737                 construct_declarator_type(construct_type, specifiers->type);
4738         type_t           *type           = skip_typeref(orig_type);
4739
4740         if (construct_type != NULL) {
4741                 obstack_free(&temp_obst, construct_type);
4742         }
4743
4744         entity_t *entity;
4745         if (specifiers->storage_class == STORAGE_CLASS_TYPEDEF) {
4746                 entity                       = allocate_entity_zero(ENTITY_TYPEDEF);
4747                 entity->base.symbol          = env.symbol;
4748                 entity->base.source_position = env.source_position;
4749                 entity->typedefe.type        = orig_type;
4750
4751                 if (anonymous_entity != NULL) {
4752                         if (is_type_compound(type)) {
4753                                 assert(anonymous_entity->compound.alias == NULL);
4754                                 assert(anonymous_entity->kind == ENTITY_STRUCT ||
4755                                        anonymous_entity->kind == ENTITY_UNION);
4756                                 anonymous_entity->compound.alias = entity;
4757                                 anonymous_entity = NULL;
4758                         } else if (is_type_enum(type)) {
4759                                 assert(anonymous_entity->enume.alias == NULL);
4760                                 assert(anonymous_entity->kind == ENTITY_ENUM);
4761                                 anonymous_entity->enume.alias = entity;
4762                                 anonymous_entity = NULL;
4763                         }
4764                 }
4765         } else {
4766                 /* create a declaration type entity */
4767                 if (flags & DECL_CREATE_COMPOUND_MEMBER) {
4768                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
4769
4770                         if (specifiers->is_inline && is_type_valid(type)) {
4771                                 errorf(&env.source_position,
4772                                                 "compound member '%Y' declared 'inline'", env.symbol);
4773                         }
4774
4775                         if (specifiers->thread_local ||
4776                                 specifiers->storage_class != STORAGE_CLASS_NONE) {
4777                                 errorf(&env.source_position,
4778                                            "compound member '%Y' must have no storage class",
4779                                            env.symbol);
4780                         }
4781                 } else if (flags & DECL_IS_PARAMETER) {
4782                         orig_type = semantic_parameter(&env.source_position, orig_type,
4783                                                        specifiers, env.symbol);
4784
4785                         entity = allocate_entity_zero(ENTITY_PARAMETER);
4786                 } else if (is_type_function(type)) {
4787                         entity = allocate_entity_zero(ENTITY_FUNCTION);
4788
4789                         entity->function.is_inline  = specifiers->is_inline;
4790                         entity->function.parameters = env.parameters;
4791
4792                         if (specifiers->thread_local || (
4793                                         specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4794                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4795                                         specifiers->storage_class != STORAGE_CLASS_STATIC)
4796                            ) {
4797                                 errorf(&env.source_position,
4798                                            "invalid storage class for function '%Y'", env.symbol);
4799                         }
4800                 } else {
4801                         entity = allocate_entity_zero(ENTITY_VARIABLE);
4802
4803                         entity->variable.get_property_sym = specifiers->get_property_sym;
4804                         entity->variable.put_property_sym = specifiers->put_property_sym;
4805                         if (specifiers->alignment != 0) {
4806                                 /* TODO: add checks here */
4807                                 entity->variable.alignment = specifiers->alignment;
4808                         }
4809
4810                         if (specifiers->is_inline && is_type_valid(type)) {
4811                                 errorf(&env.source_position,
4812                                            "variable '%Y' declared 'inline'", env.symbol);
4813                         }
4814
4815                         entity->variable.thread_local = specifiers->thread_local;
4816
4817                         bool invalid_storage_class = false;
4818                         if (current_scope == file_scope) {
4819                                 if (specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4820                                                 specifiers->storage_class != STORAGE_CLASS_NONE   &&
4821                                                 specifiers->storage_class != STORAGE_CLASS_STATIC) {
4822                                         invalid_storage_class = true;
4823                                 }
4824                         } else {
4825                                 if (specifiers->thread_local &&
4826                                                 specifiers->storage_class == STORAGE_CLASS_NONE) {
4827                                         invalid_storage_class = true;
4828                                 }
4829                         }
4830                         if (invalid_storage_class) {
4831                                 errorf(&env.source_position,
4832                                                 "invalid storage class for variable '%Y'", env.symbol);
4833                         }
4834                 }
4835
4836                 entity->base.source_position          = env.source_position;
4837                 entity->base.symbol                   = env.symbol;
4838                 entity->base.namespc                  = NAMESPACE_NORMAL;
4839                 entity->declaration.type              = orig_type;
4840                 entity->declaration.modifiers         = env.modifiers;
4841                 entity->declaration.deprecated_string = specifiers->deprecated_string;
4842
4843                 storage_class_t storage_class = specifiers->storage_class;
4844                 entity->declaration.declared_storage_class = storage_class;
4845
4846                 if (storage_class == STORAGE_CLASS_NONE && current_scope != file_scope)
4847                         storage_class = STORAGE_CLASS_AUTO;
4848                 entity->declaration.storage_class = storage_class;
4849         }
4850
4851         parse_declaration_attributes(entity);
4852
4853         return entity;
4854 }
4855
4856 static type_t *parse_abstract_declarator(type_t *base_type)
4857 {
4858         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4859
4860         type_t *result = construct_declarator_type(construct_type, base_type);
4861         if (construct_type != NULL) {
4862                 obstack_free(&temp_obst, construct_type);
4863         }
4864
4865         return result;
4866 }
4867
4868 /**
4869  * Check if the declaration of main is suspicious.  main should be a
4870  * function with external linkage, returning int, taking either zero
4871  * arguments, two, or three arguments of appropriate types, ie.
4872  *
4873  * int main([ int argc, char **argv [, char **env ] ]).
4874  *
4875  * @param decl    the declaration to check
4876  * @param type    the function type of the declaration
4877  */
4878 static void check_type_of_main(const entity_t *entity)
4879 {
4880         const source_position_t *pos = &entity->base.source_position;
4881         if (entity->kind != ENTITY_FUNCTION) {
4882                 warningf(pos, "'main' is not a function");
4883                 return;
4884         }
4885
4886         if (entity->declaration.storage_class == STORAGE_CLASS_STATIC) {
4887                 warningf(pos, "'main' is normally a non-static function");
4888         }
4889
4890         type_t *type = skip_typeref(entity->declaration.type);
4891         assert(is_type_function(type));
4892
4893         function_type_t *func_type = &type->function;
4894         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4895                 warningf(pos, "return type of 'main' should be 'int', but is '%T'",
4896                          func_type->return_type);
4897         }
4898         const function_parameter_t *parm = func_type->parameters;
4899         if (parm != NULL) {
4900                 type_t *const first_type = parm->type;
4901                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4902                         warningf(pos,
4903                                  "first argument of 'main' should be 'int', but is '%T'",
4904                                  first_type);
4905                 }
4906                 parm = parm->next;
4907                 if (parm != NULL) {
4908                         type_t *const second_type = parm->type;
4909                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4910                                 warningf(pos, "second argument of 'main' should be 'char**', but is '%T'", second_type);
4911                         }
4912                         parm = parm->next;
4913                         if (parm != NULL) {
4914                                 type_t *const third_type = parm->type;
4915                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4916                                         warningf(pos, "third argument of 'main' should be 'char**', but is '%T'", third_type);
4917                                 }
4918                                 parm = parm->next;
4919                                 if (parm != NULL)
4920                                         goto warn_arg_count;
4921                         }
4922                 } else {
4923 warn_arg_count:
4924                         warningf(pos, "'main' takes only zero, two or three arguments");
4925                 }
4926         }
4927 }
4928
4929 /**
4930  * Check if a symbol is the equal to "main".
4931  */
4932 static bool is_sym_main(const symbol_t *const sym)
4933 {
4934         return strcmp(sym->string, "main") == 0;
4935 }
4936
4937 static void error_redefined_as_different_kind(const source_position_t *pos,
4938                 const entity_t *old, entity_kind_t new_kind)
4939 {
4940         errorf(pos, "redeclaration of %s '%Y' as %s (declared %P)",
4941                get_entity_kind_name(old->kind), old->base.symbol,
4942                get_entity_kind_name(new_kind), &old->base.source_position);
4943 }
4944
4945 /**
4946  * record entities for the NAMESPACE_NORMAL, and produce error messages/warnings
4947  * for various problems that occur for multiple definitions
4948  */
4949 static entity_t *record_entity(entity_t *entity, const bool is_definition)
4950 {
4951         const symbol_t *const    symbol  = entity->base.symbol;
4952         const namespace_tag_t    namespc = (namespace_tag_t)entity->base.namespc;
4953         const source_position_t *pos     = &entity->base.source_position;
4954
4955         /* can happen in error cases */
4956         if (symbol == NULL)
4957                 return entity;
4958
4959         entity_t *previous_entity = get_entity(symbol, namespc);
4960         /* pushing the same entity twice will break the stack structure */
4961         assert(previous_entity != entity);
4962
4963         if (entity->kind == ENTITY_FUNCTION) {
4964                 type_t *const orig_type = entity->declaration.type;
4965                 type_t *const type      = skip_typeref(orig_type);
4966
4967                 assert(is_type_function(type));
4968                 if (type->function.unspecified_parameters &&
4969                                 warning.strict_prototypes &&
4970                                 previous_entity == NULL) {
4971                         warningf(pos, "function declaration '%#T' is not a prototype",
4972                                          orig_type, symbol);
4973                 }
4974
4975                 if (warning.main && current_scope == file_scope
4976                                 && is_sym_main(symbol)) {
4977                         check_type_of_main(entity);
4978                 }
4979         }
4980
4981         if (is_declaration(entity) &&
4982                         warning.nested_externs &&
4983                         entity->declaration.storage_class == STORAGE_CLASS_EXTERN &&
4984                         current_scope != file_scope) {
4985                 warningf(pos, "nested extern declaration of '%#T'",
4986                          entity->declaration.type, symbol);
4987         }
4988
4989         if (previous_entity != NULL &&
4990                         previous_entity->base.parent_scope == &current_function->parameters &&
4991                         previous_entity->base.parent_scope->depth + 1 == current_scope->depth) {
4992                 assert(previous_entity->kind == ENTITY_PARAMETER);
4993                 errorf(pos,
4994                        "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
4995                                          entity->declaration.type, symbol,
4996                                          previous_entity->declaration.type, symbol,
4997                                          &previous_entity->base.source_position);
4998                 goto finish;
4999         }
5000
5001         if (previous_entity != NULL &&
5002                         previous_entity->base.parent_scope == current_scope) {
5003                 if (previous_entity->kind != entity->kind) {
5004                         error_redefined_as_different_kind(pos, previous_entity,
5005                                                           entity->kind);
5006                         goto finish;
5007                 }
5008                 if (previous_entity->kind == ENTITY_ENUM_VALUE) {
5009                         errorf(pos, "redeclaration of enum entry '%Y' (declared %P)",
5010                                    symbol, &previous_entity->base.source_position);
5011                         goto finish;
5012                 }
5013                 if (previous_entity->kind == ENTITY_TYPEDEF) {
5014                         /* TODO: C++ allows this for exactly the same type */
5015                         errorf(pos, "redefinition of typedef '%Y' (declared %P)",
5016                                symbol, &previous_entity->base.source_position);
5017                         goto finish;
5018                 }
5019
5020                 /* at this point we should have only VARIABLES or FUNCTIONS */
5021                 assert(is_declaration(previous_entity) && is_declaration(entity));
5022
5023                 declaration_t *const prev_decl = &previous_entity->declaration;
5024                 declaration_t *const decl      = &entity->declaration;
5025
5026                 /* can happen for K&R style declarations */
5027                 if (prev_decl->type       == NULL             &&
5028                                 previous_entity->kind == ENTITY_PARAMETER &&
5029                                 entity->kind          == ENTITY_PARAMETER) {
5030                         prev_decl->type                   = decl->type;
5031                         prev_decl->storage_class          = decl->storage_class;
5032                         prev_decl->declared_storage_class = decl->declared_storage_class;
5033                         prev_decl->modifiers              = decl->modifiers;
5034                         prev_decl->deprecated_string      = decl->deprecated_string;
5035                         return previous_entity;
5036                 }
5037
5038                 type_t *const orig_type = decl->type;
5039                 assert(orig_type != NULL);
5040                 type_t *const type      = skip_typeref(orig_type);
5041                 type_t *      prev_type = skip_typeref(prev_decl->type);
5042
5043                 if (!types_compatible(type, prev_type)) {
5044                         errorf(pos,
5045                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
5046                                    orig_type, symbol, prev_decl->type, symbol,
5047                                    &previous_entity->base.source_position);
5048                 } else {
5049                         unsigned old_storage_class = prev_decl->storage_class;
5050                         if (warning.redundant_decls               &&
5051                                         is_definition                     &&
5052                                         !prev_decl->used                  &&
5053                                         !(prev_decl->modifiers & DM_USED) &&
5054                                         prev_decl->storage_class == STORAGE_CLASS_STATIC) {
5055                                 warningf(&previous_entity->base.source_position,
5056                                          "unnecessary static forward declaration for '%#T'",
5057                                          prev_decl->type, symbol);
5058                         }
5059
5060                         unsigned new_storage_class = decl->storage_class;
5061                         if (is_type_incomplete(prev_type)) {
5062                                 prev_decl->type = type;
5063                                 prev_type       = type;
5064                         }
5065
5066                         /* pretend no storage class means extern for function
5067                          * declarations (except if the previous declaration is neither
5068                          * none nor extern) */
5069                         if (entity->kind == ENTITY_FUNCTION) {
5070                                 if (prev_type->function.unspecified_parameters) {
5071                                         prev_decl->type = type;
5072                                         prev_type       = type;
5073                                 }
5074
5075                                 switch (old_storage_class) {
5076                                 case STORAGE_CLASS_NONE:
5077                                         old_storage_class = STORAGE_CLASS_EXTERN;
5078                                         /* FALLTHROUGH */
5079
5080                                 case STORAGE_CLASS_EXTERN:
5081                                         if (is_definition) {
5082                                                 if (warning.missing_prototypes &&
5083                                                     prev_type->function.unspecified_parameters &&
5084                                                     !is_sym_main(symbol)) {
5085                                                         warningf(pos, "no previous prototype for '%#T'",
5086                                                                          orig_type, symbol);
5087                                                 }
5088                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
5089                                                 new_storage_class = STORAGE_CLASS_EXTERN;
5090                                         }
5091                                         break;
5092
5093                                 default:
5094                                         break;
5095                                 }
5096                         }
5097
5098                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
5099                                         new_storage_class == STORAGE_CLASS_EXTERN) {
5100 warn_redundant_declaration:
5101                                 if (!is_definition           &&
5102                                     warning.redundant_decls  &&
5103                                     is_type_valid(prev_type) &&
5104                                     strcmp(previous_entity->base.source_position.input_name,
5105                                            "<builtin>") != 0) {
5106                                         warningf(pos,
5107                                                  "redundant declaration for '%Y' (declared %P)",
5108                                                  symbol, &previous_entity->base.source_position);
5109                                 }
5110                         } else if (current_function == NULL) {
5111                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
5112                                     new_storage_class == STORAGE_CLASS_STATIC) {
5113                                         errorf(pos,
5114                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
5115                                                symbol, &previous_entity->base.source_position);
5116                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
5117                                         prev_decl->storage_class          = STORAGE_CLASS_NONE;
5118                                         prev_decl->declared_storage_class = STORAGE_CLASS_NONE;
5119                                 } else {
5120                                         /* ISO/IEC 14882:1998(E) §C.1.2:1 */
5121                                         if (c_mode & _CXX)
5122                                                 goto error_redeclaration;
5123                                         goto warn_redundant_declaration;
5124                                 }
5125                         } else if (is_type_valid(prev_type)) {
5126                                 if (old_storage_class == new_storage_class) {
5127 error_redeclaration:
5128                                         errorf(pos, "redeclaration of '%Y' (declared %P)",
5129                                                symbol, &previous_entity->base.source_position);
5130                                 } else {
5131                                         errorf(pos,
5132                                                "redeclaration of '%Y' with different linkage (declared %P)",
5133                                                symbol, &previous_entity->base.source_position);
5134                                 }
5135                         }
5136                 }
5137
5138                 prev_decl->modifiers |= decl->modifiers;
5139                 if (entity->kind == ENTITY_FUNCTION) {
5140                         previous_entity->function.is_inline |= entity->function.is_inline;
5141                 }
5142                 return previous_entity;
5143         }
5144
5145         if (entity->kind == ENTITY_FUNCTION) {
5146                 if (is_definition &&
5147                                 entity->declaration.storage_class != STORAGE_CLASS_STATIC) {
5148                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
5149                                 warningf(pos, "no previous prototype for '%#T'",
5150                                          entity->declaration.type, symbol);
5151                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
5152                                 warningf(pos, "no previous declaration for '%#T'",
5153                                          entity->declaration.type, symbol);
5154                         }
5155                 }
5156         } else if (warning.missing_declarations &&
5157                         entity->kind == ENTITY_VARIABLE &&
5158                         current_scope == file_scope) {
5159                 declaration_t *declaration = &entity->declaration;
5160                 if (declaration->storage_class == STORAGE_CLASS_NONE) {
5161                         warningf(pos, "no previous declaration for '%#T'",
5162                                  declaration->type, symbol);
5163                 }
5164         }
5165
5166 finish:
5167         assert(entity->base.parent_scope == NULL);
5168         assert(current_scope != NULL);
5169
5170         entity->base.parent_scope = current_scope;
5171         entity->base.namespc      = NAMESPACE_NORMAL;
5172         environment_push(entity);
5173         append_entity(current_scope, entity);
5174
5175         return entity;
5176 }
5177
5178 static void parser_error_multiple_definition(entity_t *entity,
5179                 const source_position_t *source_position)
5180 {
5181         errorf(source_position, "multiple definition of '%Y' (declared %P)",
5182                entity->base.symbol, &entity->base.source_position);
5183 }
5184
5185 static bool is_declaration_specifier(const token_t *token,
5186                                      bool only_specifiers_qualifiers)
5187 {
5188         switch (token->type) {
5189                 TYPE_SPECIFIERS
5190                 TYPE_QUALIFIERS
5191                         return true;
5192                 case T_IDENTIFIER:
5193                         return is_typedef_symbol(token->v.symbol);
5194
5195                 case T___extension__:
5196                 STORAGE_CLASSES
5197                         return !only_specifiers_qualifiers;
5198
5199                 default:
5200                         return false;
5201         }
5202 }
5203
5204 static void parse_init_declarator_rest(entity_t *entity)
5205 {
5206         assert(is_declaration(entity));
5207         declaration_t *const declaration = &entity->declaration;
5208
5209         eat('=');
5210
5211         type_t *orig_type = declaration->type;
5212         type_t *type      = skip_typeref(orig_type);
5213
5214         if (entity->kind == ENTITY_VARIABLE
5215                         && entity->variable.initializer != NULL) {
5216                 parser_error_multiple_definition(entity, HERE);
5217         }
5218
5219         bool must_be_constant = false;
5220         if (declaration->storage_class == STORAGE_CLASS_STATIC ||
5221             entity->base.parent_scope  == file_scope) {
5222                 must_be_constant = true;
5223         }
5224
5225         if (is_type_function(type)) {
5226                 errorf(&entity->base.source_position,
5227                        "function '%#T' is initialized like a variable",
5228                        orig_type, entity->base.symbol);
5229                 orig_type = type_error_type;
5230         }
5231
5232         parse_initializer_env_t env;
5233         env.type             = orig_type;
5234         env.must_be_constant = must_be_constant;
5235         env.entity           = entity;
5236         current_init_decl    = entity;
5237
5238         initializer_t *initializer = parse_initializer(&env);
5239         current_init_decl = NULL;
5240
5241         if (entity->kind == ENTITY_VARIABLE) {
5242                 /* § 6.7.5 (22)  array initializers for arrays with unknown size
5243                  * determine the array type size */
5244                 declaration->type            = env.type;
5245                 entity->variable.initializer = initializer;
5246         }
5247 }
5248
5249 /* parse rest of a declaration without any declarator */
5250 static void parse_anonymous_declaration_rest(
5251                 const declaration_specifiers_t *specifiers)
5252 {
5253         eat(';');
5254         anonymous_entity = NULL;
5255
5256         if (warning.other) {
5257                 if (specifiers->storage_class != STORAGE_CLASS_NONE ||
5258                                 specifiers->thread_local) {
5259                         warningf(&specifiers->source_position,
5260                                  "useless storage class in empty declaration");
5261                 }
5262
5263                 type_t *type = specifiers->type;
5264                 switch (type->kind) {
5265                         case TYPE_COMPOUND_STRUCT:
5266                         case TYPE_COMPOUND_UNION: {
5267                                 if (type->compound.compound->base.symbol == NULL) {
5268                                         warningf(&specifiers->source_position,
5269                                                  "unnamed struct/union that defines no instances");
5270                                 }
5271                                 break;
5272                         }
5273
5274                         case TYPE_ENUM:
5275                                 break;
5276
5277                         default:
5278                                 warningf(&specifiers->source_position, "empty declaration");
5279                                 break;
5280                 }
5281         }
5282 }
5283
5284 static void check_variable_type_complete(entity_t *ent)
5285 {
5286         if (ent->kind != ENTITY_VARIABLE)
5287                 return;
5288
5289         /* §6.7:7  If an identifier for an object is declared with no linkage, the
5290          *         type for the object shall be complete [...] */
5291         declaration_t *decl = &ent->declaration;
5292         if (decl->storage_class != STORAGE_CLASS_NONE)
5293                 return;
5294
5295         type_t *const orig_type = decl->type;
5296         type_t *const type      = skip_typeref(orig_type);
5297         if (!is_type_incomplete(type))
5298                 return;
5299
5300         /* GCC allows global arrays without size and assigns them a length of one,
5301          * if no different declaration follows */
5302         if (is_type_array(type) &&
5303                         c_mode & _GNUC      &&
5304                         ent->base.parent_scope == file_scope) {
5305                 ARR_APP1(declaration_t*, incomplete_arrays, decl);
5306                 return;
5307         }
5308
5309         errorf(&ent->base.source_position, "variable '%#T' has incomplete type",
5310                         orig_type, ent->base.symbol);
5311 }
5312
5313
5314 static void parse_declaration_rest(entity_t *ndeclaration,
5315                 const declaration_specifiers_t *specifiers,
5316                 parsed_declaration_func         finished_declaration,
5317                 declarator_flags_t              flags)
5318 {
5319         add_anchor_token(';');
5320         add_anchor_token(',');
5321         while (true) {
5322                 entity_t *entity = finished_declaration(ndeclaration, token.type == '=');
5323
5324                 if (token.type == '=') {
5325                         parse_init_declarator_rest(entity);
5326                 } else if (entity->kind == ENTITY_VARIABLE) {
5327                         /* ISO/IEC 14882:1998(E) §8.5.3:3  The initializer can be omitted
5328                          * [...] where the extern specifier is explicitly used. */
5329                         declaration_t *decl = &entity->declaration;
5330                         if (decl->storage_class != STORAGE_CLASS_EXTERN) {
5331                                 type_t *type = decl->type;
5332                                 if (is_type_reference(skip_typeref(type))) {
5333                                         errorf(&entity->base.source_position,
5334                                                         "reference '%#T' must be initialized",
5335                                                         type, entity->base.symbol);
5336                                 }
5337                         }
5338                 }
5339
5340                 check_variable_type_complete(entity);
5341
5342                 if (token.type != ',')
5343                         break;
5344                 eat(',');
5345
5346                 add_anchor_token('=');
5347                 ndeclaration = parse_declarator(specifiers, flags);
5348                 rem_anchor_token('=');
5349         }
5350         expect(';', end_error);
5351
5352 end_error:
5353         anonymous_entity = NULL;
5354         rem_anchor_token(';');
5355         rem_anchor_token(',');
5356 }
5357
5358 static entity_t *finished_kr_declaration(entity_t *entity, bool is_definition)
5359 {
5360         symbol_t *symbol = entity->base.symbol;
5361         if (symbol == NULL) {
5362                 errorf(HERE, "anonymous declaration not valid as function parameter");
5363                 return entity;
5364         }
5365
5366         assert(entity->base.namespc == NAMESPACE_NORMAL);
5367         entity_t *previous_entity = get_entity(symbol, NAMESPACE_NORMAL);
5368         if (previous_entity == NULL
5369                         || previous_entity->base.parent_scope != current_scope) {
5370                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
5371                        symbol);
5372                 return entity;
5373         }
5374
5375         if (is_definition) {
5376                 errorf(HERE, "parameter '%Y' is initialised", entity->base.symbol);
5377         }
5378
5379         return record_entity(entity, false);
5380 }
5381
5382 static void parse_declaration(parsed_declaration_func finished_declaration,
5383                               declarator_flags_t      flags)
5384 {
5385         declaration_specifiers_t specifiers;
5386         memset(&specifiers, 0, sizeof(specifiers));
5387
5388         add_anchor_token(';');
5389         parse_declaration_specifiers(&specifiers);
5390         rem_anchor_token(';');
5391
5392         if (token.type == ';') {
5393                 parse_anonymous_declaration_rest(&specifiers);
5394         } else {
5395                 entity_t *entity = parse_declarator(&specifiers, flags);
5396                 parse_declaration_rest(entity, &specifiers, finished_declaration, flags);
5397         }
5398 }
5399
5400 static type_t *get_default_promoted_type(type_t *orig_type)
5401 {
5402         type_t *result = orig_type;
5403
5404         type_t *type = skip_typeref(orig_type);
5405         if (is_type_integer(type)) {
5406                 result = promote_integer(type);
5407         } else if (type == type_float) {
5408                 result = type_double;
5409         }
5410
5411         return result;
5412 }
5413
5414 static void parse_kr_declaration_list(entity_t *entity)
5415 {
5416         if (entity->kind != ENTITY_FUNCTION)
5417                 return;
5418
5419         type_t *type = skip_typeref(entity->declaration.type);
5420         assert(is_type_function(type));
5421         if (!type->function.kr_style_parameters)
5422                 return;
5423
5424
5425         add_anchor_token('{');
5426
5427         /* push function parameters */
5428         size_t const  top       = environment_top();
5429         scope_t      *old_scope = scope_push(&entity->function.parameters);
5430
5431         entity_t *parameter = entity->function.parameters.entities;
5432         for ( ; parameter != NULL; parameter = parameter->base.next) {
5433                 assert(parameter->base.parent_scope == NULL);
5434                 parameter->base.parent_scope = current_scope;
5435                 environment_push(parameter);
5436         }
5437
5438         /* parse declaration list */
5439         for (;;) {
5440                 switch (token.type) {
5441                         DECLARATION_START
5442                         case T___extension__:
5443                         /* This covers symbols, which are no type, too, and results in
5444                          * better error messages.  The typical cases are misspelled type
5445                          * names and missing includes. */
5446                         case T_IDENTIFIER:
5447                                 parse_declaration(finished_kr_declaration, DECL_IS_PARAMETER);
5448                                 break;
5449                         default:
5450                                 goto decl_list_end;
5451                 }
5452         }
5453 decl_list_end:
5454
5455         /* pop function parameters */
5456         assert(current_scope == &entity->function.parameters);
5457         scope_pop(old_scope);
5458         environment_pop_to(top);
5459
5460         /* update function type */
5461         type_t *new_type = duplicate_type(type);
5462
5463         function_parameter_t *parameters     = NULL;
5464         function_parameter_t *last_parameter = NULL;
5465
5466         parameter = entity->function.parameters.entities;
5467         for (; parameter != NULL; parameter = parameter->base.next) {
5468                 type_t *parameter_type = parameter->declaration.type;
5469                 if (parameter_type == NULL) {
5470                         if (strict_mode) {
5471                                 errorf(HERE, "no type specified for function parameter '%Y'",
5472                                        parameter->base.symbol);
5473                         } else {
5474                                 if (warning.implicit_int) {
5475                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
5476                                                  parameter->base.symbol);
5477                                 }
5478                                 parameter_type              = type_int;
5479                                 parameter->declaration.type = parameter_type;
5480                         }
5481                 }
5482
5483                 semantic_parameter_incomplete(parameter);
5484                 parameter_type = parameter->declaration.type;
5485
5486                 /*
5487                  * we need the default promoted types for the function type
5488                  */
5489                 parameter_type = get_default_promoted_type(parameter_type);
5490
5491                 function_parameter_t *function_parameter
5492                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
5493                 memset(function_parameter, 0, sizeof(function_parameter[0]));
5494
5495                 function_parameter->type = parameter_type;
5496                 if (last_parameter != NULL) {
5497                         last_parameter->next = function_parameter;
5498                 } else {
5499                         parameters = function_parameter;
5500                 }
5501                 last_parameter = function_parameter;
5502         }
5503
5504         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
5505          * prototype */
5506         new_type->function.parameters             = parameters;
5507         new_type->function.unspecified_parameters = true;
5508
5509         type = typehash_insert(new_type);
5510         if (type != new_type) {
5511                 obstack_free(type_obst, new_type);
5512         }
5513
5514         entity->declaration.type = type;
5515
5516         rem_anchor_token('{');
5517 }
5518
5519 static bool first_err = true;
5520
5521 /**
5522  * When called with first_err set, prints the name of the current function,
5523  * else does noting.
5524  */
5525 static void print_in_function(void)
5526 {
5527         if (first_err) {
5528                 first_err = false;
5529                 diagnosticf("%s: In function '%Y':\n",
5530                             current_function->base.base.source_position.input_name,
5531                             current_function->base.base.symbol);
5532         }
5533 }
5534
5535 /**
5536  * Check if all labels are defined in the current function.
5537  * Check if all labels are used in the current function.
5538  */
5539 static void check_labels(void)
5540 {
5541         for (const goto_statement_t *goto_statement = goto_first;
5542             goto_statement != NULL;
5543             goto_statement = goto_statement->next) {
5544                 /* skip computed gotos */
5545                 if (goto_statement->expression != NULL)
5546                         continue;
5547
5548                 label_t *label = goto_statement->label;
5549
5550                 label->used = true;
5551                 if (label->base.source_position.input_name == NULL) {
5552                         print_in_function();
5553                         errorf(&goto_statement->base.source_position,
5554                                "label '%Y' used but not defined", label->base.symbol);
5555                  }
5556         }
5557
5558         if (warning.unused_label) {
5559                 for (const label_statement_t *label_statement = label_first;
5560                          label_statement != NULL;
5561                          label_statement = label_statement->next) {
5562                         label_t *label = label_statement->label;
5563
5564                         if (! label->used) {
5565                                 print_in_function();
5566                                 warningf(&label_statement->base.source_position,
5567                                          "label '%Y' defined but not used", label->base.symbol);
5568                         }
5569                 }
5570         }
5571 }
5572
5573 static void warn_unused_entity(entity_t *entity, entity_t *end)
5574 {
5575         for (; entity != NULL; entity = entity->base.next) {
5576                 if (!is_declaration(entity))
5577                         continue;
5578
5579                 declaration_t *declaration = &entity->declaration;
5580                 if (declaration->implicit)
5581                         continue;
5582
5583                 if (!declaration->used) {
5584                         print_in_function();
5585                         const char *what = get_entity_kind_name(entity->kind);
5586                         warningf(&entity->base.source_position, "%s '%Y' is unused",
5587                                  what, entity->base.symbol);
5588                 } else if (entity->kind == ENTITY_VARIABLE && !entity->variable.read) {
5589                         print_in_function();
5590                         const char *what = get_entity_kind_name(entity->kind);
5591                         warningf(&entity->base.source_position, "%s '%Y' is never read",
5592                                  what, entity->base.symbol);
5593                 }
5594
5595                 if (entity == end)
5596                         break;
5597         }
5598 }
5599
5600 static void check_unused_variables(statement_t *const stmt, void *const env)
5601 {
5602         (void)env;
5603
5604         switch (stmt->kind) {
5605                 case STATEMENT_DECLARATION: {
5606                         declaration_statement_t const *const decls = &stmt->declaration;
5607                         warn_unused_entity(decls->declarations_begin,
5608                                            decls->declarations_end);
5609                         return;
5610                 }
5611
5612                 case STATEMENT_FOR:
5613                         warn_unused_entity(stmt->fors.scope.entities, NULL);
5614                         return;
5615
5616                 default:
5617                         return;
5618         }
5619 }
5620
5621 /**
5622  * Check declarations of current_function for unused entities.
5623  */
5624 static void check_declarations(void)
5625 {
5626         if (warning.unused_parameter) {
5627                 const scope_t *scope = &current_function->parameters;
5628
5629                 /* do not issue unused warnings for main */
5630                 if (!is_sym_main(current_function->base.base.symbol)) {
5631                         warn_unused_entity(scope->entities, NULL);
5632                 }
5633         }
5634         if (warning.unused_variable) {
5635                 walk_statements(current_function->statement, check_unused_variables,
5636                                 NULL);
5637         }
5638 }
5639
5640 static int determine_truth(expression_t const* const cond)
5641 {
5642         return
5643                 !is_constant_expression(cond) ? 0 :
5644                 fold_constant(cond) != 0      ? 1 :
5645                 -1;
5646 }
5647
5648 static void check_reachable(statement_t *);
5649
5650 static bool expression_returns(expression_t const *const expr)
5651 {
5652         switch (expr->kind) {
5653                 case EXPR_CALL: {
5654                         expression_t const *const func = expr->call.function;
5655                         if (func->kind == EXPR_REFERENCE) {
5656                                 entity_t *entity = func->reference.entity;
5657                                 if (entity->kind == ENTITY_FUNCTION
5658                                                 && entity->declaration.modifiers & DM_NORETURN)
5659                                         return false;
5660                         }
5661
5662                         if (!expression_returns(func))
5663                                 return false;
5664
5665                         for (call_argument_t const* arg = expr->call.arguments; arg != NULL; arg = arg->next) {
5666                                 if (!expression_returns(arg->expression))
5667                                         return false;
5668                         }
5669
5670                         return true;
5671                 }
5672
5673                 case EXPR_REFERENCE:
5674                 case EXPR_REFERENCE_ENUM_VALUE:
5675                 case EXPR_CONST:
5676                 case EXPR_CHARACTER_CONSTANT:
5677                 case EXPR_WIDE_CHARACTER_CONSTANT:
5678                 case EXPR_STRING_LITERAL:
5679                 case EXPR_WIDE_STRING_LITERAL:
5680                 case EXPR_COMPOUND_LITERAL: // TODO descend into initialisers
5681                 case EXPR_LABEL_ADDRESS:
5682                 case EXPR_CLASSIFY_TYPE:
5683                 case EXPR_SIZEOF: // TODO handle obscure VLA case
5684                 case EXPR_ALIGNOF:
5685                 case EXPR_FUNCNAME:
5686                 case EXPR_BUILTIN_SYMBOL:
5687                 case EXPR_BUILTIN_CONSTANT_P:
5688                 case EXPR_BUILTIN_PREFETCH:
5689                 case EXPR_OFFSETOF:
5690                 case EXPR_INVALID:
5691                         return true;
5692
5693                 case EXPR_STATEMENT:
5694                         check_reachable(expr->statement.statement);
5695                         // TODO check if statement can be left
5696                         return true;
5697
5698                 case EXPR_CONDITIONAL:
5699                         // TODO handle constant expression
5700
5701                         if (!expression_returns(expr->conditional.condition))
5702                                 return false;
5703
5704                         if (expr->conditional.true_expression != NULL
5705                                         && expression_returns(expr->conditional.true_expression))
5706                                 return true;
5707
5708                         return expression_returns(expr->conditional.false_expression);
5709
5710                 case EXPR_SELECT:
5711                         return expression_returns(expr->select.compound);
5712
5713                 case EXPR_ARRAY_ACCESS:
5714                         return
5715                                 expression_returns(expr->array_access.array_ref) &&
5716                                 expression_returns(expr->array_access.index);
5717
5718                 case EXPR_VA_START:
5719                         return expression_returns(expr->va_starte.ap);
5720
5721                 case EXPR_VA_ARG:
5722                         return expression_returns(expr->va_arge.ap);
5723
5724                 EXPR_UNARY_CASES_MANDATORY
5725                         return expression_returns(expr->unary.value);
5726
5727                 case EXPR_UNARY_THROW:
5728                         return false;
5729
5730                 EXPR_BINARY_CASES
5731                         // TODO handle constant lhs of && and ||
5732                         return
5733                                 expression_returns(expr->binary.left) &&
5734                                 expression_returns(expr->binary.right);
5735
5736                 case EXPR_UNKNOWN:
5737                         break;
5738         }
5739
5740         panic("unhandled expression");
5741 }
5742
5743 static bool initializer_returns(initializer_t const *const init)
5744 {
5745         switch (init->kind) {
5746                 case INITIALIZER_VALUE:
5747                         return expression_returns(init->value.value);
5748
5749                 case INITIALIZER_LIST: {
5750                         initializer_t * const*       i       = init->list.initializers;
5751                         initializer_t * const* const end     = i + init->list.len;
5752                         bool                         returns = true;
5753                         for (; i != end; ++i) {
5754                                 if (!initializer_returns(*i))
5755                                         returns = false;
5756                         }
5757                         return returns;
5758                 }
5759
5760                 case INITIALIZER_STRING:
5761                 case INITIALIZER_WIDE_STRING:
5762                 case INITIALIZER_DESIGNATOR: // designators have no payload
5763                         return true;
5764         }
5765         panic("unhandled initializer");
5766 }
5767
5768 static bool noreturn_candidate;
5769
5770 static void check_reachable(statement_t *const stmt)
5771 {
5772         if (stmt->base.reachable)
5773                 return;
5774         if (stmt->kind != STATEMENT_DO_WHILE)
5775                 stmt->base.reachable = true;
5776
5777         statement_t *last = stmt;
5778         statement_t *next;
5779         switch (stmt->kind) {
5780                 case STATEMENT_INVALID:
5781                 case STATEMENT_EMPTY:
5782                 case STATEMENT_LOCAL_LABEL:
5783                 case STATEMENT_ASM:
5784                         next = stmt->base.next;
5785                         break;
5786
5787                 case STATEMENT_DECLARATION: {
5788                         declaration_statement_t const *const decl = &stmt->declaration;
5789                         entity_t                const *      ent  = decl->declarations_begin;
5790                         entity_t                const *const last = decl->declarations_end;
5791                         if (ent != NULL) {
5792                                 for (;; ent = ent->base.next) {
5793                                         if (ent->kind                 == ENTITY_VARIABLE &&
5794                                                         ent->variable.initializer != NULL            &&
5795                                                         !initializer_returns(ent->variable.initializer)) {
5796                                                 return;
5797                                         }
5798                                         if (ent == last)
5799                                                 break;
5800                                 }
5801                         }
5802                         next = stmt->base.next;
5803                         break;
5804                 }
5805
5806                 case STATEMENT_COMPOUND:
5807                         next = stmt->compound.statements;
5808                         break;
5809
5810                 case STATEMENT_RETURN: {
5811                         expression_t const *const val = stmt->returns.value;
5812                         if (val == NULL || expression_returns(val))
5813                                 noreturn_candidate = false;
5814                         return;
5815                 }
5816
5817                 case STATEMENT_IF: {
5818                         if_statement_t const *const ifs  = &stmt->ifs;
5819                         expression_t   const *const cond = ifs->condition;
5820
5821                         if (!expression_returns(cond))
5822                                 return;
5823
5824                         int const val = determine_truth(cond);
5825
5826                         if (val >= 0)
5827                                 check_reachable(ifs->true_statement);
5828
5829                         if (val > 0)
5830                                 return;
5831
5832                         if (ifs->false_statement != NULL) {
5833                                 check_reachable(ifs->false_statement);
5834                                 return;
5835                         }
5836
5837                         next = stmt->base.next;
5838                         break;
5839                 }
5840
5841                 case STATEMENT_SWITCH: {
5842                         switch_statement_t const *const switchs = &stmt->switchs;
5843                         expression_t       const *const expr    = switchs->expression;
5844
5845                         if (!expression_returns(expr))
5846                                 return;
5847
5848                         if (is_constant_expression(expr)) {
5849                                 long                    const val      = fold_constant(expr);
5850                                 case_label_statement_t *      defaults = NULL;
5851                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5852                                         if (i->expression == NULL) {
5853                                                 defaults = i;
5854                                                 continue;
5855                                         }
5856
5857                                         if (i->first_case <= val && val <= i->last_case) {
5858                                                 check_reachable((statement_t*)i);
5859                                                 return;
5860                                         }
5861                                 }
5862
5863                                 if (defaults != NULL) {
5864                                         check_reachable((statement_t*)defaults);
5865                                         return;
5866                                 }
5867                         } else {
5868                                 bool has_default = false;
5869                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5870                                         if (i->expression == NULL)
5871                                                 has_default = true;
5872
5873                                         check_reachable((statement_t*)i);
5874                                 }
5875
5876                                 if (has_default)
5877                                         return;
5878                         }
5879
5880                         next = stmt->base.next;
5881                         break;
5882                 }
5883
5884                 case STATEMENT_EXPRESSION: {
5885                         /* Check for noreturn function call */
5886                         expression_t const *const expr = stmt->expression.expression;
5887                         if (!expression_returns(expr))
5888                                 return;
5889
5890                         next = stmt->base.next;
5891                         break;
5892                 }
5893
5894                 case STATEMENT_CONTINUE: {
5895                         statement_t *parent = stmt;
5896                         for (;;) {
5897                                 parent = parent->base.parent;
5898                                 if (parent == NULL) /* continue not within loop */
5899                                         return;
5900
5901                                 next = parent;
5902                                 switch (parent->kind) {
5903                                         case STATEMENT_WHILE:    goto continue_while;
5904                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5905                                         case STATEMENT_FOR:      goto continue_for;
5906
5907                                         default: break;
5908                                 }
5909                         }
5910                 }
5911
5912                 case STATEMENT_BREAK: {
5913                         statement_t *parent = stmt;
5914                         for (;;) {
5915                                 parent = parent->base.parent;
5916                                 if (parent == NULL) /* break not within loop/switch */
5917                                         return;
5918
5919                                 switch (parent->kind) {
5920                                         case STATEMENT_SWITCH:
5921                                         case STATEMENT_WHILE:
5922                                         case STATEMENT_DO_WHILE:
5923                                         case STATEMENT_FOR:
5924                                                 last = parent;
5925                                                 next = parent->base.next;
5926                                                 goto found_break_parent;
5927
5928                                         default: break;
5929                                 }
5930                         }
5931 found_break_parent:
5932                         break;
5933                 }
5934
5935                 case STATEMENT_GOTO:
5936                         if (stmt->gotos.expression) {
5937                                 if (!expression_returns(stmt->gotos.expression))
5938                                         return;
5939
5940                                 statement_t *parent = stmt->base.parent;
5941                                 if (parent == NULL) /* top level goto */
5942                                         return;
5943                                 next = parent;
5944                         } else {
5945                                 next = stmt->gotos.label->statement;
5946                                 if (next == NULL) /* missing label */
5947                                         return;
5948                         }
5949                         break;
5950
5951                 case STATEMENT_LABEL:
5952                         next = stmt->label.statement;
5953                         break;
5954
5955                 case STATEMENT_CASE_LABEL:
5956                         next = stmt->case_label.statement;
5957                         break;
5958
5959                 case STATEMENT_WHILE: {
5960                         while_statement_t const *const whiles = &stmt->whiles;
5961                         expression_t      const *const cond   = whiles->condition;
5962
5963                         if (!expression_returns(cond))
5964                                 return;
5965
5966                         int const val = determine_truth(cond);
5967
5968                         if (val >= 0)
5969                                 check_reachable(whiles->body);
5970
5971                         if (val > 0)
5972                                 return;
5973
5974                         next = stmt->base.next;
5975                         break;
5976                 }
5977
5978                 case STATEMENT_DO_WHILE:
5979                         next = stmt->do_while.body;
5980                         break;
5981
5982                 case STATEMENT_FOR: {
5983                         for_statement_t *const fors = &stmt->fors;
5984
5985                         if (fors->condition_reachable)
5986                                 return;
5987                         fors->condition_reachable = true;
5988
5989                         expression_t const *const cond = fors->condition;
5990
5991                         int val;
5992                         if (cond == NULL) {
5993                                 val = 1;
5994                         } else if (expression_returns(cond)) {
5995                                 val = determine_truth(cond);
5996                         } else {
5997                                 return;
5998                         }
5999
6000                         if (val >= 0)
6001                                 check_reachable(fors->body);
6002
6003                         if (val > 0)
6004                                 return;
6005
6006                         next = stmt->base.next;
6007                         break;
6008                 }
6009
6010                 case STATEMENT_MS_TRY: {
6011                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
6012                         check_reachable(ms_try->try_statement);
6013                         next = ms_try->final_statement;
6014                         break;
6015                 }
6016
6017                 case STATEMENT_LEAVE: {
6018                         statement_t *parent = stmt;
6019                         for (;;) {
6020                                 parent = parent->base.parent;
6021                                 if (parent == NULL) /* __leave not within __try */
6022                                         return;
6023
6024                                 if (parent->kind == STATEMENT_MS_TRY) {
6025                                         last = parent;
6026                                         next = parent->ms_try.final_statement;
6027                                         break;
6028                                 }
6029                         }
6030                         break;
6031                 }
6032         }
6033
6034         while (next == NULL) {
6035                 next = last->base.parent;
6036                 if (next == NULL) {
6037                         noreturn_candidate = false;
6038
6039                         type_t *const type = current_function->base.type;
6040                         assert(is_type_function(type));
6041                         type_t *const ret  = skip_typeref(type->function.return_type);
6042                         if (warning.return_type                    &&
6043                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
6044                             is_type_valid(ret)                     &&
6045                             !is_sym_main(current_function->base.base.symbol)) {
6046                                 warningf(&stmt->base.source_position,
6047                                          "control reaches end of non-void function");
6048                         }
6049                         return;
6050                 }
6051
6052                 switch (next->kind) {
6053                         case STATEMENT_INVALID:
6054                         case STATEMENT_EMPTY:
6055                         case STATEMENT_DECLARATION:
6056                         case STATEMENT_LOCAL_LABEL:
6057                         case STATEMENT_EXPRESSION:
6058                         case STATEMENT_ASM:
6059                         case STATEMENT_RETURN:
6060                         case STATEMENT_CONTINUE:
6061                         case STATEMENT_BREAK:
6062                         case STATEMENT_GOTO:
6063                         case STATEMENT_LEAVE:
6064                                 panic("invalid control flow in function");
6065
6066                         case STATEMENT_COMPOUND:
6067                         case STATEMENT_IF:
6068                         case STATEMENT_SWITCH:
6069                         case STATEMENT_LABEL:
6070                         case STATEMENT_CASE_LABEL:
6071                                 last = next;
6072                                 next = next->base.next;
6073                                 break;
6074
6075                         case STATEMENT_WHILE: {
6076 continue_while:
6077                                 if (next->base.reachable)
6078                                         return;
6079                                 next->base.reachable = true;
6080
6081                                 while_statement_t const *const whiles = &next->whiles;
6082                                 expression_t      const *const cond   = whiles->condition;
6083
6084                                 if (!expression_returns(cond))
6085                                         return;
6086
6087                                 int const val = determine_truth(cond);
6088
6089                                 if (val >= 0)
6090                                         check_reachable(whiles->body);
6091
6092                                 if (val > 0)
6093                                         return;
6094
6095                                 last = next;
6096                                 next = next->base.next;
6097                                 break;
6098                         }
6099
6100                         case STATEMENT_DO_WHILE: {
6101 continue_do_while:
6102                                 if (next->base.reachable)
6103                                         return;
6104                                 next->base.reachable = true;
6105
6106                                 do_while_statement_t const *const dw   = &next->do_while;
6107                                 expression_t         const *const cond = dw->condition;
6108
6109                                 if (!expression_returns(cond))
6110                                         return;
6111
6112                                 int const val = determine_truth(cond);
6113
6114                                 if (val >= 0)
6115                                         check_reachable(dw->body);
6116
6117                                 if (val > 0)
6118                                         return;
6119
6120                                 last = next;
6121                                 next = next->base.next;
6122                                 break;
6123                         }
6124
6125                         case STATEMENT_FOR: {
6126 continue_for:;
6127                                 for_statement_t *const fors = &next->fors;
6128
6129                                 fors->step_reachable = true;
6130
6131                                 if (fors->condition_reachable)
6132                                         return;
6133                                 fors->condition_reachable = true;
6134
6135                                 expression_t const *const cond = fors->condition;
6136
6137                                 int val;
6138                                 if (cond == NULL) {
6139                                         val = 1;
6140                                 } else if (expression_returns(cond)) {
6141                                         val = determine_truth(cond);
6142                                 } else {
6143                                         return;
6144                                 }
6145
6146                                 if (val >= 0)
6147                                         check_reachable(fors->body);
6148
6149                                 if (val > 0)
6150                                         return;
6151
6152                                 last = next;
6153                                 next = next->base.next;
6154                                 break;
6155                         }
6156
6157                         case STATEMENT_MS_TRY:
6158                                 last = next;
6159                                 next = next->ms_try.final_statement;
6160                                 break;
6161                 }
6162         }
6163
6164         check_reachable(next);
6165 }
6166
6167 static void check_unreachable(statement_t* const stmt, void *const env)
6168 {
6169         (void)env;
6170
6171         switch (stmt->kind) {
6172                 case STATEMENT_DO_WHILE:
6173                         if (!stmt->base.reachable) {
6174                                 expression_t const *const cond = stmt->do_while.condition;
6175                                 if (determine_truth(cond) >= 0) {
6176                                         warningf(&cond->base.source_position,
6177                                                  "condition of do-while-loop is unreachable");
6178                                 }
6179                         }
6180                         return;
6181
6182                 case STATEMENT_FOR: {
6183                         for_statement_t const* const fors = &stmt->fors;
6184
6185                         // if init and step are unreachable, cond is unreachable, too
6186                         if (!stmt->base.reachable && !fors->step_reachable) {
6187                                 warningf(&stmt->base.source_position, "statement is unreachable");
6188                         } else {
6189                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
6190                                         warningf(&fors->initialisation->base.source_position,
6191                                                  "initialisation of for-statement is unreachable");
6192                                 }
6193
6194                                 if (!fors->condition_reachable && fors->condition != NULL) {
6195                                         warningf(&fors->condition->base.source_position,
6196                                                  "condition of for-statement is unreachable");
6197                                 }
6198
6199                                 if (!fors->step_reachable && fors->step != NULL) {
6200                                         warningf(&fors->step->base.source_position,
6201                                                  "step of for-statement is unreachable");
6202                                 }
6203                         }
6204                         return;
6205                 }
6206
6207                 case STATEMENT_COMPOUND:
6208                         if (stmt->compound.statements != NULL)
6209                                 return;
6210                         goto warn_unreachable;
6211
6212                 case STATEMENT_DECLARATION: {
6213                         /* Only warn if there is at least one declarator with an initializer.
6214                          * This typically occurs in switch statements. */
6215                         declaration_statement_t const *const decl = &stmt->declaration;
6216                         entity_t                const *      ent  = decl->declarations_begin;
6217                         entity_t                const *const last = decl->declarations_end;
6218                         if (ent != NULL) {
6219                                 for (;; ent = ent->base.next) {
6220                                         if (ent->kind                 == ENTITY_VARIABLE &&
6221                                                         ent->variable.initializer != NULL) {
6222                                                 goto warn_unreachable;
6223                                         }
6224                                         if (ent == last)
6225                                                 return;
6226                                 }
6227                         }
6228                 }
6229
6230                 default:
6231 warn_unreachable:
6232                         if (!stmt->base.reachable)
6233                                 warningf(&stmt->base.source_position, "statement is unreachable");
6234                         return;
6235         }
6236 }
6237
6238 static void parse_external_declaration(void)
6239 {
6240         /* function-definitions and declarations both start with declaration
6241          * specifiers */
6242         declaration_specifiers_t specifiers;
6243         memset(&specifiers, 0, sizeof(specifiers));
6244
6245         add_anchor_token(';');
6246         parse_declaration_specifiers(&specifiers);
6247         rem_anchor_token(';');
6248
6249         /* must be a declaration */
6250         if (token.type == ';') {
6251                 parse_anonymous_declaration_rest(&specifiers);
6252                 return;
6253         }
6254
6255         add_anchor_token(',');
6256         add_anchor_token('=');
6257         add_anchor_token(';');
6258         add_anchor_token('{');
6259
6260         /* declarator is common to both function-definitions and declarations */
6261         entity_t *ndeclaration = parse_declarator(&specifiers, DECL_FLAGS_NONE);
6262
6263         rem_anchor_token('{');
6264         rem_anchor_token(';');
6265         rem_anchor_token('=');
6266         rem_anchor_token(',');
6267
6268         /* must be a declaration */
6269         switch (token.type) {
6270                 case ',':
6271                 case ';':
6272                 case '=':
6273                         parse_declaration_rest(ndeclaration, &specifiers, record_entity,
6274                                         DECL_FLAGS_NONE);
6275                         return;
6276         }
6277
6278         /* must be a function definition */
6279         parse_kr_declaration_list(ndeclaration);
6280
6281         if (token.type != '{') {
6282                 parse_error_expected("while parsing function definition", '{', NULL);
6283                 eat_until_matching_token(';');
6284                 return;
6285         }
6286
6287         assert(is_declaration(ndeclaration));
6288         type_t *type = skip_typeref(ndeclaration->declaration.type);
6289
6290         if (!is_type_function(type)) {
6291                 if (is_type_valid(type)) {
6292                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
6293                                type, ndeclaration->base.symbol);
6294                 }
6295                 eat_block();
6296                 return;
6297         }
6298
6299         if (warning.aggregate_return &&
6300             is_type_compound(skip_typeref(type->function.return_type))) {
6301                 warningf(HERE, "function '%Y' returns an aggregate",
6302                          ndeclaration->base.symbol);
6303         }
6304         if (warning.traditional && !type->function.unspecified_parameters) {
6305                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
6306                         ndeclaration->base.symbol);
6307         }
6308         if (warning.old_style_definition && type->function.unspecified_parameters) {
6309                 warningf(HERE, "old-style function definition '%Y'",
6310                         ndeclaration->base.symbol);
6311         }
6312
6313         /* § 6.7.5.3 (14) a function definition with () means no
6314          * parameters (and not unspecified parameters) */
6315         if (type->function.unspecified_parameters
6316                         && type->function.parameters == NULL
6317                         && !type->function.kr_style_parameters) {
6318                 type_t *duplicate = duplicate_type(type);
6319                 duplicate->function.unspecified_parameters = false;
6320
6321                 type = typehash_insert(duplicate);
6322                 if (type != duplicate) {
6323                         obstack_free(type_obst, duplicate);
6324                 }
6325                 ndeclaration->declaration.type = type;
6326         }
6327
6328         entity_t *const entity = record_entity(ndeclaration, true);
6329         assert(entity->kind == ENTITY_FUNCTION);
6330         assert(ndeclaration->kind == ENTITY_FUNCTION);
6331
6332         function_t *function = &entity->function;
6333         if (ndeclaration != entity) {
6334                 function->parameters = ndeclaration->function.parameters;
6335         }
6336         assert(is_declaration(entity));
6337         type = skip_typeref(entity->declaration.type);
6338
6339         /* push function parameters and switch scope */
6340         size_t const  top       = environment_top();
6341         scope_t      *old_scope = scope_push(&function->parameters);
6342
6343         entity_t *parameter = function->parameters.entities;
6344         for (; parameter != NULL; parameter = parameter->base.next) {
6345                 if (parameter->base.parent_scope == &ndeclaration->function.parameters) {
6346                         parameter->base.parent_scope = current_scope;
6347                 }
6348                 assert(parameter->base.parent_scope == NULL
6349                                 || parameter->base.parent_scope == current_scope);
6350                 parameter->base.parent_scope = current_scope;
6351                 if (parameter->base.symbol == NULL) {
6352                         errorf(&parameter->base.source_position, "parameter name omitted");
6353                         continue;
6354                 }
6355                 environment_push(parameter);
6356         }
6357
6358         if (function->statement != NULL) {
6359                 parser_error_multiple_definition(entity, HERE);
6360                 eat_block();
6361         } else {
6362                 /* parse function body */
6363                 int         label_stack_top      = label_top();
6364                 function_t *old_current_function = current_function;
6365                 current_function                 = function;
6366                 current_parent                   = NULL;
6367
6368                 goto_first   = NULL;
6369                 goto_anchor  = &goto_first;
6370                 label_first  = NULL;
6371                 label_anchor = &label_first;
6372
6373                 statement_t *const body = parse_compound_statement(false);
6374                 function->statement = body;
6375                 first_err = true;
6376                 check_labels();
6377                 check_declarations();
6378                 if (warning.return_type      ||
6379                     warning.unreachable_code ||
6380                     (warning.missing_noreturn
6381                      && !(function->base.modifiers & DM_NORETURN))) {
6382                         noreturn_candidate = true;
6383                         check_reachable(body);
6384                         if (warning.unreachable_code)
6385                                 walk_statements(body, check_unreachable, NULL);
6386                         if (warning.missing_noreturn &&
6387                             noreturn_candidate       &&
6388                             !(function->base.modifiers & DM_NORETURN)) {
6389                                 warningf(&body->base.source_position,
6390                                          "function '%#T' is candidate for attribute 'noreturn'",
6391                                          type, entity->base.symbol);
6392                         }
6393                 }
6394
6395                 assert(current_parent   == NULL);
6396                 assert(current_function == function);
6397                 current_function = old_current_function;
6398                 label_pop_to(label_stack_top);
6399         }
6400
6401         assert(current_scope == &function->parameters);
6402         scope_pop(old_scope);
6403         environment_pop_to(top);
6404 }
6405
6406 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
6407                                   source_position_t *source_position,
6408                                   const symbol_t *symbol)
6409 {
6410         type_t *type = allocate_type_zero(TYPE_BITFIELD);
6411
6412         type->bitfield.base_type       = base_type;
6413         type->bitfield.size_expression = size;
6414
6415         il_size_t bit_size;
6416         type_t *skipped_type = skip_typeref(base_type);
6417         if (!is_type_integer(skipped_type)) {
6418                 errorf(HERE, "bitfield base type '%T' is not an integer type",
6419                         base_type);
6420                 bit_size = 0;
6421         } else {
6422                 bit_size = skipped_type->base.size * 8;
6423         }
6424
6425         if (is_constant_expression(size)) {
6426                 long v = fold_constant(size);
6427
6428                 if (v < 0) {
6429                         errorf(source_position, "negative width in bit-field '%Y'", symbol);
6430                 } else if (v == 0) {
6431                         errorf(source_position, "zero width for bit-field '%Y'", symbol);
6432                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
6433                         errorf(source_position, "width of '%Y' exceeds its type", symbol);
6434                 } else {
6435                         type->bitfield.bit_size = v;
6436                 }
6437         }
6438
6439         return type;
6440 }
6441
6442 static entity_t *find_compound_entry(compound_t *compound, symbol_t *symbol)
6443 {
6444         entity_t *iter = compound->members.entities;
6445         for (; iter != NULL; iter = iter->base.next) {
6446                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
6447                         continue;
6448
6449                 if (iter->base.symbol == symbol) {
6450                         return iter;
6451                 } else if (iter->base.symbol == NULL) {
6452                         type_t *type = skip_typeref(iter->declaration.type);
6453                         if (is_type_compound(type)) {
6454                                 entity_t *result
6455                                         = find_compound_entry(type->compound.compound, symbol);
6456                                 if (result != NULL)
6457                                         return result;
6458                         }
6459                         continue;
6460                 }
6461         }
6462
6463         return NULL;
6464 }
6465
6466 static void parse_compound_declarators(compound_t *compound,
6467                 const declaration_specifiers_t *specifiers)
6468 {
6469         while (true) {
6470                 entity_t *entity;
6471
6472                 if (token.type == ':') {
6473                         source_position_t source_position = *HERE;
6474                         next_token();
6475
6476                         type_t *base_type = specifiers->type;
6477                         expression_t *size = parse_constant_expression();
6478
6479                         type_t *type = make_bitfield_type(base_type, size,
6480                                         &source_position, sym_anonymous);
6481
6482                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
6483                         entity->base.namespc                       = NAMESPACE_NORMAL;
6484                         entity->base.source_position               = source_position;
6485                         entity->declaration.declared_storage_class = STORAGE_CLASS_NONE;
6486                         entity->declaration.storage_class          = STORAGE_CLASS_NONE;
6487                         entity->declaration.modifiers              = specifiers->modifiers;
6488                         entity->declaration.type                   = type;
6489                 } else {
6490                         entity = parse_declarator(specifiers,
6491                                         DECL_MAY_BE_ABSTRACT | DECL_CREATE_COMPOUND_MEMBER);
6492                         assert(entity->kind == ENTITY_COMPOUND_MEMBER);
6493
6494                         if (token.type == ':') {
6495                                 source_position_t source_position = *HERE;
6496                                 next_token();
6497                                 expression_t *size = parse_constant_expression();
6498
6499                                 type_t *type = entity->declaration.type;
6500                                 type_t *bitfield_type = make_bitfield_type(type, size,
6501                                                 &source_position, entity->base.symbol);
6502                                 entity->declaration.type = bitfield_type;
6503                         }
6504                 }
6505
6506                 /* make sure we don't define a symbol multiple times */
6507                 symbol_t *symbol = entity->base.symbol;
6508                 if (symbol != NULL) {
6509                         entity_t *prev = find_compound_entry(compound, symbol);
6510
6511                         if (prev != NULL) {
6512                                 errorf(&entity->base.source_position,
6513                                        "multiple declarations of symbol '%Y' (declared %P)",
6514                                        symbol, &prev->base.source_position);
6515                         }
6516                 }
6517
6518                 append_entity(&compound->members, entity);
6519
6520                 type_t *orig_type = entity->declaration.type;
6521                 type_t *type      = skip_typeref(orig_type);
6522                 if (is_type_function(type)) {
6523                         errorf(&entity->base.source_position,
6524                                         "compound member '%Y' must not have function type '%T'",
6525                                         entity->base.symbol, orig_type);
6526                 } else if (is_type_incomplete(type)) {
6527                         /* §6.7.2.1:16 flexible array member */
6528                         if (is_type_array(type) &&
6529                                         token.type == ';'   &&
6530                                         look_ahead(1)->type == '}') {
6531                                 compound->has_flexible_member = true;
6532                         } else {
6533                                 errorf(&entity->base.source_position,
6534                                                 "compound member '%Y' has incomplete type '%T'",
6535                                                 entity->base.symbol, orig_type);
6536                         }
6537                 }
6538
6539                 if (token.type != ',')
6540                         break;
6541                 next_token();
6542         }
6543         expect(';', end_error);
6544
6545 end_error:
6546         anonymous_entity = NULL;
6547 }
6548
6549 static void parse_compound_type_entries(compound_t *compound)
6550 {
6551         eat('{');
6552         add_anchor_token('}');
6553
6554         while (token.type != '}') {
6555                 if (token.type == T_EOF) {
6556                         errorf(HERE, "EOF while parsing struct");
6557                         break;
6558                 }
6559                 declaration_specifiers_t specifiers;
6560                 memset(&specifiers, 0, sizeof(specifiers));
6561                 parse_declaration_specifiers(&specifiers);
6562
6563                 parse_compound_declarators(compound, &specifiers);
6564         }
6565         rem_anchor_token('}');
6566         next_token();
6567
6568         /* §6.7.2.1:7 */
6569         compound->complete = true;
6570 }
6571
6572 static type_t *parse_typename(void)
6573 {
6574         declaration_specifiers_t specifiers;
6575         memset(&specifiers, 0, sizeof(specifiers));
6576         parse_declaration_specifiers(&specifiers);
6577         if (specifiers.storage_class != STORAGE_CLASS_NONE ||
6578                         specifiers.thread_local) {
6579                 /* TODO: improve error message, user does probably not know what a
6580                  * storage class is...
6581                  */
6582                 errorf(HERE, "typename may not have a storage class");
6583         }
6584
6585         type_t *result = parse_abstract_declarator(specifiers.type);
6586
6587         return result;
6588 }
6589
6590
6591
6592
6593 typedef expression_t* (*parse_expression_function)(void);
6594 typedef expression_t* (*parse_expression_infix_function)(expression_t *left);
6595
6596 typedef struct expression_parser_function_t expression_parser_function_t;
6597 struct expression_parser_function_t {
6598         parse_expression_function        parser;
6599         unsigned                         infix_precedence;
6600         parse_expression_infix_function  infix_parser;
6601 };
6602
6603 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
6604
6605 /**
6606  * Prints an error message if an expression was expected but not read
6607  */
6608 static expression_t *expected_expression_error(void)
6609 {
6610         /* skip the error message if the error token was read */
6611         if (token.type != T_ERROR) {
6612                 errorf(HERE, "expected expression, got token %K", &token);
6613         }
6614         next_token();
6615
6616         return create_invalid_expression();
6617 }
6618
6619 /**
6620  * Parse a string constant.
6621  */
6622 static expression_t *parse_string_const(void)
6623 {
6624         wide_string_t wres;
6625         if (token.type == T_STRING_LITERAL) {
6626                 string_t res = token.v.string;
6627                 next_token();
6628                 while (token.type == T_STRING_LITERAL) {
6629                         res = concat_strings(&res, &token.v.string);
6630                         next_token();
6631                 }
6632                 if (token.type != T_WIDE_STRING_LITERAL) {
6633                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
6634                         /* note: that we use type_char_ptr here, which is already the
6635                          * automatic converted type. revert_automatic_type_conversion
6636                          * will construct the array type */
6637                         cnst->base.type    = warning.write_strings ? type_const_char_ptr : type_char_ptr;
6638                         cnst->string.value = res;
6639                         return cnst;
6640                 }
6641
6642                 wres = concat_string_wide_string(&res, &token.v.wide_string);
6643         } else {
6644                 wres = token.v.wide_string;
6645         }
6646         next_token();
6647
6648         for (;;) {
6649                 switch (token.type) {
6650                         case T_WIDE_STRING_LITERAL:
6651                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
6652                                 break;
6653
6654                         case T_STRING_LITERAL:
6655                                 wres = concat_wide_string_string(&wres, &token.v.string);
6656                                 break;
6657
6658                         default: {
6659                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
6660                                 cnst->base.type         = warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
6661                                 cnst->wide_string.value = wres;
6662                                 return cnst;
6663                         }
6664                 }
6665                 next_token();
6666         }
6667 }
6668
6669 /**
6670  * Parse a boolean constant.
6671  */
6672 static expression_t *parse_bool_const(bool value)
6673 {
6674         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6675         cnst->base.type          = type_bool;
6676         cnst->conste.v.int_value = value;
6677
6678         next_token();
6679
6680         return cnst;
6681 }
6682
6683 /**
6684  * Parse an integer constant.
6685  */
6686 static expression_t *parse_int_const(void)
6687 {
6688         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6689         cnst->base.type          = token.datatype;
6690         cnst->conste.v.int_value = token.v.intvalue;
6691
6692         next_token();
6693
6694         return cnst;
6695 }
6696
6697 /**
6698  * Parse a character constant.
6699  */
6700 static expression_t *parse_character_constant(void)
6701 {
6702         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
6703         cnst->base.type          = token.datatype;
6704         cnst->conste.v.character = token.v.string;
6705
6706         if (cnst->conste.v.character.size != 1) {
6707                 if (!GNU_MODE) {
6708                         errorf(HERE, "more than 1 character in character constant");
6709                 } else if (warning.multichar) {
6710                         warningf(HERE, "multi-character character constant");
6711                 }
6712         }
6713         next_token();
6714
6715         return cnst;
6716 }
6717
6718 /**
6719  * Parse a wide character constant.
6720  */
6721 static expression_t *parse_wide_character_constant(void)
6722 {
6723         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
6724         cnst->base.type               = token.datatype;
6725         cnst->conste.v.wide_character = token.v.wide_string;
6726
6727         if (cnst->conste.v.wide_character.size != 1) {
6728                 if (!GNU_MODE) {
6729                         errorf(HERE, "more than 1 character in character constant");
6730                 } else if (warning.multichar) {
6731                         warningf(HERE, "multi-character character constant");
6732                 }
6733         }
6734         next_token();
6735
6736         return cnst;
6737 }
6738
6739 /**
6740  * Parse a float constant.
6741  */
6742 static expression_t *parse_float_const(void)
6743 {
6744         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6745         cnst->base.type            = token.datatype;
6746         cnst->conste.v.float_value = token.v.floatvalue;
6747
6748         next_token();
6749
6750         return cnst;
6751 }
6752
6753 static entity_t *create_implicit_function(symbol_t *symbol,
6754                 const source_position_t *source_position)
6755 {
6756         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION);
6757         ntype->function.return_type            = type_int;
6758         ntype->function.unspecified_parameters = true;
6759
6760         type_t *type = typehash_insert(ntype);
6761         if (type != ntype) {
6762                 free_type(ntype);
6763         }
6764
6765         entity_t *entity = allocate_entity_zero(ENTITY_FUNCTION);
6766         entity->declaration.storage_class          = STORAGE_CLASS_EXTERN;
6767         entity->declaration.declared_storage_class = STORAGE_CLASS_EXTERN;
6768         entity->declaration.type                   = type;
6769         entity->declaration.implicit               = true;
6770         entity->base.symbol                        = symbol;
6771         entity->base.source_position               = *source_position;
6772
6773         bool strict_prototypes_old = warning.strict_prototypes;
6774         warning.strict_prototypes  = false;
6775         record_entity(entity, false);
6776         warning.strict_prototypes = strict_prototypes_old;
6777
6778         return entity;
6779 }
6780
6781 /**
6782  * Creates a return_type (func)(argument_type) function type if not
6783  * already exists.
6784  */
6785 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
6786                                     type_t *argument_type2)
6787 {
6788         function_parameter_t *parameter2
6789                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
6790         memset(parameter2, 0, sizeof(parameter2[0]));
6791         parameter2->type = argument_type2;
6792
6793         function_parameter_t *parameter1
6794                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
6795         memset(parameter1, 0, sizeof(parameter1[0]));
6796         parameter1->type = argument_type1;
6797         parameter1->next = parameter2;
6798
6799         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6800         type->function.return_type = return_type;
6801         type->function.parameters  = parameter1;
6802
6803         type_t *result = typehash_insert(type);
6804         if (result != type) {
6805                 free_type(type);
6806         }
6807
6808         return result;
6809 }
6810
6811 /**
6812  * Creates a return_type (func)(argument_type) function type if not
6813  * already exists.
6814  *
6815  * @param return_type    the return type
6816  * @param argument_type  the argument type
6817  */
6818 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
6819 {
6820         function_parameter_t *parameter
6821                 = obstack_alloc(type_obst, sizeof(parameter[0]));
6822         memset(parameter, 0, sizeof(parameter[0]));
6823         parameter->type = argument_type;
6824
6825         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6826         type->function.return_type = return_type;
6827         type->function.parameters  = parameter;
6828
6829         type_t *result = typehash_insert(type);
6830         if (result != type) {
6831                 free_type(type);
6832         }
6833
6834         return result;
6835 }
6836
6837 static type_t *make_function_0_type(type_t *return_type)
6838 {
6839         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6840         type->function.return_type = return_type;
6841         type->function.parameters  = NULL;
6842
6843         type_t *result = typehash_insert(type);
6844         if (result != type) {
6845                 free_type(type);
6846         }
6847
6848         return result;
6849 }
6850
6851 /**
6852  * Creates a function type for some function like builtins.
6853  *
6854  * @param symbol   the symbol describing the builtin
6855  */
6856 static type_t *get_builtin_symbol_type(symbol_t *symbol)
6857 {
6858         switch (symbol->ID) {
6859         case T___builtin_alloca:
6860                 return make_function_1_type(type_void_ptr, type_size_t);
6861         case T___builtin_huge_val:
6862                 return make_function_0_type(type_double);
6863         case T___builtin_inf:
6864                 return make_function_0_type(type_double);
6865         case T___builtin_inff:
6866                 return make_function_0_type(type_float);
6867         case T___builtin_infl:
6868                 return make_function_0_type(type_long_double);
6869         case T___builtin_nan:
6870                 return make_function_1_type(type_double, type_char_ptr);
6871         case T___builtin_nanf:
6872                 return make_function_1_type(type_float, type_char_ptr);
6873         case T___builtin_nanl:
6874                 return make_function_1_type(type_long_double, type_char_ptr);
6875         case T___builtin_va_end:
6876                 return make_function_1_type(type_void, type_valist);
6877         case T___builtin_expect:
6878                 return make_function_2_type(type_long, type_long, type_long);
6879         default:
6880                 internal_errorf(HERE, "not implemented builtin identifier found");
6881         }
6882 }
6883
6884 /**
6885  * Performs automatic type cast as described in § 6.3.2.1.
6886  *
6887  * @param orig_type  the original type
6888  */
6889 static type_t *automatic_type_conversion(type_t *orig_type)
6890 {
6891         type_t *type = skip_typeref(orig_type);
6892         if (is_type_array(type)) {
6893                 array_type_t *array_type   = &type->array;
6894                 type_t       *element_type = array_type->element_type;
6895                 unsigned      qualifiers   = array_type->base.qualifiers;
6896
6897                 return make_pointer_type(element_type, qualifiers);
6898         }
6899
6900         if (is_type_function(type)) {
6901                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6902         }
6903
6904         return orig_type;
6905 }
6906
6907 /**
6908  * reverts the automatic casts of array to pointer types and function
6909  * to function-pointer types as defined § 6.3.2.1
6910  */
6911 type_t *revert_automatic_type_conversion(const expression_t *expression)
6912 {
6913         switch (expression->kind) {
6914                 case EXPR_REFERENCE: {
6915                         entity_t *entity = expression->reference.entity;
6916                         if (is_declaration(entity)) {
6917                                 return entity->declaration.type;
6918                         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6919                                 return entity->enum_value.enum_type;
6920                         } else {
6921                                 panic("no declaration or enum in reference");
6922                         }
6923                 }
6924
6925                 case EXPR_SELECT: {
6926                         entity_t *entity = expression->select.compound_entry;
6927                         assert(is_declaration(entity));
6928                         type_t   *type   = entity->declaration.type;
6929                         return get_qualified_type(type,
6930                                                   expression->base.type->base.qualifiers);
6931                 }
6932
6933                 case EXPR_UNARY_DEREFERENCE: {
6934                         const expression_t *const value = expression->unary.value;
6935                         type_t             *const type  = skip_typeref(value->base.type);
6936                         assert(is_type_pointer(type));
6937                         return type->pointer.points_to;
6938                 }
6939
6940                 case EXPR_BUILTIN_SYMBOL:
6941                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
6942
6943                 case EXPR_ARRAY_ACCESS: {
6944                         const expression_t *array_ref = expression->array_access.array_ref;
6945                         type_t             *type_left = skip_typeref(array_ref->base.type);
6946                         if (!is_type_valid(type_left))
6947                                 return type_left;
6948                         assert(is_type_pointer(type_left));
6949                         return type_left->pointer.points_to;
6950                 }
6951
6952                 case EXPR_STRING_LITERAL: {
6953                         size_t size = expression->string.value.size;
6954                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
6955                 }
6956
6957                 case EXPR_WIDE_STRING_LITERAL: {
6958                         size_t size = expression->wide_string.value.size;
6959                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
6960                 }
6961
6962                 case EXPR_COMPOUND_LITERAL:
6963                         return expression->compound_literal.type;
6964
6965                 default: break;
6966         }
6967
6968         return expression->base.type;
6969 }
6970
6971 static expression_t *parse_reference(void)
6972 {
6973         symbol_t *const symbol = token.v.symbol;
6974
6975         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
6976
6977         if (entity == NULL) {
6978                 if (!strict_mode && look_ahead(1)->type == '(') {
6979                         /* an implicitly declared function */
6980                         if (warning.error_implicit_function_declaration) {
6981                                 errorf(HERE, "implicit declaration of function '%Y'", symbol);
6982                         } else if (warning.implicit_function_declaration) {
6983                                 warningf(HERE, "implicit declaration of function '%Y'", symbol);
6984                         }
6985
6986                         entity = create_implicit_function(symbol, HERE);
6987                 } else {
6988                         errorf(HERE, "unknown identifier '%Y' found.", symbol);
6989                         entity = create_error_entity(symbol, ENTITY_VARIABLE);
6990                 }
6991         }
6992
6993         type_t *orig_type;
6994
6995         if (is_declaration(entity)) {
6996                 orig_type = entity->declaration.type;
6997         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6998                 orig_type = entity->enum_value.enum_type;
6999         } else if (entity->kind == ENTITY_TYPEDEF) {
7000                 errorf(HERE, "encountered typedef name '%Y' while parsing expression",
7001                         symbol);
7002                 next_token();
7003                 return create_invalid_expression();
7004         } else {
7005                 panic("expected declaration or enum value in reference");
7006         }
7007
7008         /* we always do the auto-type conversions; the & and sizeof parser contains
7009          * code to revert this! */
7010         type_t *type = automatic_type_conversion(orig_type);
7011
7012         expression_kind_t kind = EXPR_REFERENCE;
7013         if (entity->kind == ENTITY_ENUM_VALUE)
7014                 kind = EXPR_REFERENCE_ENUM_VALUE;
7015
7016         expression_t *expression     = allocate_expression_zero(kind);
7017         expression->reference.entity = entity;
7018         expression->base.type        = type;
7019
7020         /* this declaration is used */
7021         if (is_declaration(entity)) {
7022                 entity->declaration.used = true;
7023         }
7024
7025         if (entity->base.parent_scope != file_scope
7026                 && entity->base.parent_scope->depth < current_function->parameters.depth
7027                 && is_type_valid(orig_type) && !is_type_function(orig_type)) {
7028                 if (entity->kind == ENTITY_VARIABLE) {
7029                         /* access of a variable from an outer function */
7030                         entity->variable.address_taken = true;
7031                 } else if (entity->kind == ENTITY_PARAMETER) {
7032                         entity->parameter.address_taken = true;
7033                 }
7034                 current_function->need_closure = true;
7035         }
7036
7037         /* check for deprecated functions */
7038         if (warning.deprecated_declarations
7039                 && is_declaration(entity)
7040                 && entity->declaration.modifiers & DM_DEPRECATED) {
7041                 declaration_t *declaration = &entity->declaration;
7042
7043                 char const *const prefix = entity->kind == ENTITY_FUNCTION ?
7044                         "function" : "variable";
7045
7046                 if (declaration->deprecated_string != NULL) {
7047                         warningf(HERE, "%s '%Y' is deprecated (declared %P): \"%s\"",
7048                                  prefix, entity->base.symbol, &entity->base.source_position,
7049                                  declaration->deprecated_string);
7050                 } else {
7051                         warningf(HERE, "%s '%Y' is deprecated (declared %P)", prefix,
7052                                  entity->base.symbol, &entity->base.source_position);
7053                 }
7054         }
7055
7056         if (warning.init_self && entity == current_init_decl && !in_type_prop
7057             && entity->kind == ENTITY_VARIABLE) {
7058                 current_init_decl = NULL;
7059                 warningf(HERE, "variable '%#T' is initialized by itself",
7060                          entity->declaration.type, entity->base.symbol);
7061         }
7062
7063         next_token();
7064         return expression;
7065 }
7066
7067 static bool semantic_cast(expression_t *cast)
7068 {
7069         expression_t            *expression      = cast->unary.value;
7070         type_t                  *orig_dest_type  = cast->base.type;
7071         type_t                  *orig_type_right = expression->base.type;
7072         type_t            const *dst_type        = skip_typeref(orig_dest_type);
7073         type_t            const *src_type        = skip_typeref(orig_type_right);
7074         source_position_t const *pos             = &cast->base.source_position;
7075
7076         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
7077         if (dst_type == type_void)
7078                 return true;
7079
7080         /* only integer and pointer can be casted to pointer */
7081         if (is_type_pointer(dst_type)  &&
7082             !is_type_pointer(src_type) &&
7083             !is_type_integer(src_type) &&
7084             is_type_valid(src_type)) {
7085                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
7086                 return false;
7087         }
7088
7089         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
7090                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
7091                 return false;
7092         }
7093
7094         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
7095                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
7096                 return false;
7097         }
7098
7099         if (warning.cast_qual &&
7100             is_type_pointer(src_type) &&
7101             is_type_pointer(dst_type)) {
7102                 type_t *src = skip_typeref(src_type->pointer.points_to);
7103                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
7104                 unsigned missing_qualifiers =
7105                         src->base.qualifiers & ~dst->base.qualifiers;
7106                 if (missing_qualifiers != 0) {
7107                         warningf(pos,
7108                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
7109                                  missing_qualifiers, orig_type_right);
7110                 }
7111         }
7112         return true;
7113 }
7114
7115 static expression_t *parse_compound_literal(type_t *type)
7116 {
7117         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
7118
7119         parse_initializer_env_t env;
7120         env.type             = type;
7121         env.entity           = NULL;
7122         env.must_be_constant = false;
7123         initializer_t *initializer = parse_initializer(&env);
7124         type = env.type;
7125
7126         expression->compound_literal.initializer = initializer;
7127         expression->compound_literal.type        = type;
7128         expression->base.type                    = automatic_type_conversion(type);
7129
7130         return expression;
7131 }
7132
7133 /**
7134  * Parse a cast expression.
7135  */
7136 static expression_t *parse_cast(void)
7137 {
7138         add_anchor_token(')');
7139
7140         source_position_t source_position = token.source_position;
7141
7142         type_t *type = parse_typename();
7143
7144         rem_anchor_token(')');
7145         expect(')', end_error);
7146
7147         if (token.type == '{') {
7148                 return parse_compound_literal(type);
7149         }
7150
7151         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
7152         cast->base.source_position = source_position;
7153
7154         expression_t *value = parse_sub_expression(PREC_CAST);
7155         cast->base.type   = type;
7156         cast->unary.value = value;
7157
7158         if (! semantic_cast(cast)) {
7159                 /* TODO: record the error in the AST. else it is impossible to detect it */
7160         }
7161
7162         return cast;
7163 end_error:
7164         return create_invalid_expression();
7165 }
7166
7167 /**
7168  * Parse a statement expression.
7169  */
7170 static expression_t *parse_statement_expression(void)
7171 {
7172         add_anchor_token(')');
7173
7174         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
7175
7176         statement_t *statement          = parse_compound_statement(true);
7177         expression->statement.statement = statement;
7178
7179         /* find last statement and use its type */
7180         type_t *type = type_void;
7181         const statement_t *stmt = statement->compound.statements;
7182         if (stmt != NULL) {
7183                 while (stmt->base.next != NULL)
7184                         stmt = stmt->base.next;
7185
7186                 if (stmt->kind == STATEMENT_EXPRESSION) {
7187                         type = stmt->expression.expression->base.type;
7188                 }
7189         } else if (warning.other) {
7190                 warningf(&expression->base.source_position, "empty statement expression ({})");
7191         }
7192         expression->base.type = type;
7193
7194         rem_anchor_token(')');
7195         expect(')', end_error);
7196
7197 end_error:
7198         return expression;
7199 }
7200
7201 /**
7202  * Parse a parenthesized expression.
7203  */
7204 static expression_t *parse_parenthesized_expression(void)
7205 {
7206         eat('(');
7207
7208         switch (token.type) {
7209         case '{':
7210                 /* gcc extension: a statement expression */
7211                 return parse_statement_expression();
7212
7213         TYPE_QUALIFIERS
7214         TYPE_SPECIFIERS
7215                 return parse_cast();
7216         case T_IDENTIFIER:
7217                 if (is_typedef_symbol(token.v.symbol)) {
7218                         return parse_cast();
7219                 }
7220         }
7221
7222         add_anchor_token(')');
7223         expression_t *result = parse_expression();
7224         rem_anchor_token(')');
7225         expect(')', end_error);
7226
7227 end_error:
7228         return result;
7229 }
7230
7231 static expression_t *parse_function_keyword(void)
7232 {
7233         /* TODO */
7234
7235         if (current_function == NULL) {
7236                 errorf(HERE, "'__func__' used outside of a function");
7237         }
7238
7239         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7240         expression->base.type     = type_char_ptr;
7241         expression->funcname.kind = FUNCNAME_FUNCTION;
7242
7243         next_token();
7244
7245         return expression;
7246 }
7247
7248 static expression_t *parse_pretty_function_keyword(void)
7249 {
7250         if (current_function == NULL) {
7251                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
7252         }
7253
7254         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7255         expression->base.type     = type_char_ptr;
7256         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
7257
7258         eat(T___PRETTY_FUNCTION__);
7259
7260         return expression;
7261 }
7262
7263 static expression_t *parse_funcsig_keyword(void)
7264 {
7265         if (current_function == NULL) {
7266                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
7267         }
7268
7269         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7270         expression->base.type     = type_char_ptr;
7271         expression->funcname.kind = FUNCNAME_FUNCSIG;
7272
7273         eat(T___FUNCSIG__);
7274
7275         return expression;
7276 }
7277
7278 static expression_t *parse_funcdname_keyword(void)
7279 {
7280         if (current_function == NULL) {
7281                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
7282         }
7283
7284         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7285         expression->base.type     = type_char_ptr;
7286         expression->funcname.kind = FUNCNAME_FUNCDNAME;
7287
7288         eat(T___FUNCDNAME__);
7289
7290         return expression;
7291 }
7292
7293 static designator_t *parse_designator(void)
7294 {
7295         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
7296         result->source_position = *HERE;
7297
7298         if (token.type != T_IDENTIFIER) {
7299                 parse_error_expected("while parsing member designator",
7300                                      T_IDENTIFIER, NULL);
7301                 return NULL;
7302         }
7303         result->symbol = token.v.symbol;
7304         next_token();
7305
7306         designator_t *last_designator = result;
7307         while (true) {
7308                 if (token.type == '.') {
7309                         next_token();
7310                         if (token.type != T_IDENTIFIER) {
7311                                 parse_error_expected("while parsing member designator",
7312                                                      T_IDENTIFIER, NULL);
7313                                 return NULL;
7314                         }
7315                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7316                         designator->source_position = *HERE;
7317                         designator->symbol          = token.v.symbol;
7318                         next_token();
7319
7320                         last_designator->next = designator;
7321                         last_designator       = designator;
7322                         continue;
7323                 }
7324                 if (token.type == '[') {
7325                         next_token();
7326                         add_anchor_token(']');
7327                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7328                         designator->source_position = *HERE;
7329                         designator->array_index     = parse_expression();
7330                         rem_anchor_token(']');
7331                         expect(']', end_error);
7332                         if (designator->array_index == NULL) {
7333                                 return NULL;
7334                         }
7335
7336                         last_designator->next = designator;
7337                         last_designator       = designator;
7338                         continue;
7339                 }
7340                 break;
7341         }
7342
7343         return result;
7344 end_error:
7345         return NULL;
7346 }
7347
7348 /**
7349  * Parse the __builtin_offsetof() expression.
7350  */
7351 static expression_t *parse_offsetof(void)
7352 {
7353         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
7354         expression->base.type    = type_size_t;
7355
7356         eat(T___builtin_offsetof);
7357
7358         expect('(', end_error);
7359         add_anchor_token(',');
7360         type_t *type = parse_typename();
7361         rem_anchor_token(',');
7362         expect(',', end_error);
7363         add_anchor_token(')');
7364         designator_t *designator = parse_designator();
7365         rem_anchor_token(')');
7366         expect(')', end_error);
7367
7368         expression->offsetofe.type       = type;
7369         expression->offsetofe.designator = designator;
7370
7371         type_path_t path;
7372         memset(&path, 0, sizeof(path));
7373         path.top_type = type;
7374         path.path     = NEW_ARR_F(type_path_entry_t, 0);
7375
7376         descend_into_subtype(&path);
7377
7378         if (!walk_designator(&path, designator, true)) {
7379                 return create_invalid_expression();
7380         }
7381
7382         DEL_ARR_F(path.path);
7383
7384         return expression;
7385 end_error:
7386         return create_invalid_expression();
7387 }
7388
7389 /**
7390  * Parses a _builtin_va_start() expression.
7391  */
7392 static expression_t *parse_va_start(void)
7393 {
7394         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
7395
7396         eat(T___builtin_va_start);
7397
7398         expect('(', end_error);
7399         add_anchor_token(',');
7400         expression->va_starte.ap = parse_assignment_expression();
7401         rem_anchor_token(',');
7402         expect(',', end_error);
7403         expression_t *const expr = parse_assignment_expression();
7404         if (expr->kind == EXPR_REFERENCE) {
7405                 entity_t *const entity = expr->reference.entity;
7406                 if (entity->base.parent_scope != &current_function->parameters
7407                                 || entity->base.next != NULL
7408                                 || entity->kind != ENTITY_PARAMETER) {
7409                         errorf(&expr->base.source_position,
7410                                "second argument of 'va_start' must be last parameter of the current function");
7411                 } else {
7412                         expression->va_starte.parameter = &entity->variable;
7413                 }
7414                 expect(')', end_error);
7415                 return expression;
7416         }
7417         expect(')', end_error);
7418 end_error:
7419         return create_invalid_expression();
7420 }
7421
7422 /**
7423  * Parses a _builtin_va_arg() expression.
7424  */
7425 static expression_t *parse_va_arg(void)
7426 {
7427         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
7428
7429         eat(T___builtin_va_arg);
7430
7431         expect('(', end_error);
7432         expression->va_arge.ap = parse_assignment_expression();
7433         expect(',', end_error);
7434         expression->base.type = parse_typename();
7435         expect(')', end_error);
7436
7437         return expression;
7438 end_error:
7439         return create_invalid_expression();
7440 }
7441
7442 static expression_t *parse_builtin_symbol(void)
7443 {
7444         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
7445
7446         symbol_t *symbol = token.v.symbol;
7447
7448         expression->builtin_symbol.symbol = symbol;
7449         next_token();
7450
7451         type_t *type = get_builtin_symbol_type(symbol);
7452         type = automatic_type_conversion(type);
7453
7454         expression->base.type = type;
7455         return expression;
7456 }
7457
7458 /**
7459  * Parses a __builtin_constant() expression.
7460  */
7461 static expression_t *parse_builtin_constant(void)
7462 {
7463         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
7464
7465         eat(T___builtin_constant_p);
7466
7467         expect('(', end_error);
7468         add_anchor_token(')');
7469         expression->builtin_constant.value = parse_assignment_expression();
7470         rem_anchor_token(')');
7471         expect(')', end_error);
7472         expression->base.type = type_int;
7473
7474         return expression;
7475 end_error:
7476         return create_invalid_expression();
7477 }
7478
7479 /**
7480  * Parses a __builtin_prefetch() expression.
7481  */
7482 static expression_t *parse_builtin_prefetch(void)
7483 {
7484         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
7485
7486         eat(T___builtin_prefetch);
7487
7488         expect('(', end_error);
7489         add_anchor_token(')');
7490         expression->builtin_prefetch.adr = parse_assignment_expression();
7491         if (token.type == ',') {
7492                 next_token();
7493                 expression->builtin_prefetch.rw = parse_assignment_expression();
7494         }
7495         if (token.type == ',') {
7496                 next_token();
7497                 expression->builtin_prefetch.locality = parse_assignment_expression();
7498         }
7499         rem_anchor_token(')');
7500         expect(')', end_error);
7501         expression->base.type = type_void;
7502
7503         return expression;
7504 end_error:
7505         return create_invalid_expression();
7506 }
7507
7508 /**
7509  * Parses a __builtin_is_*() compare expression.
7510  */
7511 static expression_t *parse_compare_builtin(void)
7512 {
7513         expression_t *expression;
7514
7515         switch (token.type) {
7516         case T___builtin_isgreater:
7517                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
7518                 break;
7519         case T___builtin_isgreaterequal:
7520                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
7521                 break;
7522         case T___builtin_isless:
7523                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
7524                 break;
7525         case T___builtin_islessequal:
7526                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
7527                 break;
7528         case T___builtin_islessgreater:
7529                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
7530                 break;
7531         case T___builtin_isunordered:
7532                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
7533                 break;
7534         default:
7535                 internal_errorf(HERE, "invalid compare builtin found");
7536         }
7537         expression->base.source_position = *HERE;
7538         next_token();
7539
7540         expect('(', end_error);
7541         expression->binary.left = parse_assignment_expression();
7542         expect(',', end_error);
7543         expression->binary.right = parse_assignment_expression();
7544         expect(')', end_error);
7545
7546         type_t *const orig_type_left  = expression->binary.left->base.type;
7547         type_t *const orig_type_right = expression->binary.right->base.type;
7548
7549         type_t *const type_left  = skip_typeref(orig_type_left);
7550         type_t *const type_right = skip_typeref(orig_type_right);
7551         if (!is_type_float(type_left) && !is_type_float(type_right)) {
7552                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7553                         type_error_incompatible("invalid operands in comparison",
7554                                 &expression->base.source_position, orig_type_left, orig_type_right);
7555                 }
7556         } else {
7557                 semantic_comparison(&expression->binary);
7558         }
7559
7560         return expression;
7561 end_error:
7562         return create_invalid_expression();
7563 }
7564
7565 #if 0
7566 /**
7567  * Parses a __builtin_expect(, end_error) expression.
7568  */
7569 static expression_t *parse_builtin_expect(void, end_error)
7570 {
7571         expression_t *expression
7572                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
7573
7574         eat(T___builtin_expect);
7575
7576         expect('(', end_error);
7577         expression->binary.left = parse_assignment_expression();
7578         expect(',', end_error);
7579         expression->binary.right = parse_constant_expression();
7580         expect(')', end_error);
7581
7582         expression->base.type = expression->binary.left->base.type;
7583
7584         return expression;
7585 end_error:
7586         return create_invalid_expression();
7587 }
7588 #endif
7589
7590 /**
7591  * Parses a MS assume() expression.
7592  */
7593 static expression_t *parse_assume(void)
7594 {
7595         expression_t *expression = allocate_expression_zero(EXPR_UNARY_ASSUME);
7596
7597         eat(T__assume);
7598
7599         expect('(', end_error);
7600         add_anchor_token(')');
7601         expression->unary.value = parse_assignment_expression();
7602         rem_anchor_token(')');
7603         expect(')', end_error);
7604
7605         expression->base.type = type_void;
7606         return expression;
7607 end_error:
7608         return create_invalid_expression();
7609 }
7610
7611 /**
7612  * Return the declaration for a given label symbol or create a new one.
7613  *
7614  * @param symbol  the symbol of the label
7615  */
7616 static label_t *get_label(symbol_t *symbol)
7617 {
7618         entity_t *label;
7619         assert(current_function != NULL);
7620
7621         label = get_entity(symbol, NAMESPACE_LABEL);
7622         /* if we found a local label, we already created the declaration */
7623         if (label != NULL && label->kind == ENTITY_LOCAL_LABEL) {
7624                 if (label->base.parent_scope != current_scope) {
7625                         assert(label->base.parent_scope->depth < current_scope->depth);
7626                         current_function->goto_to_outer = true;
7627                 }
7628                 return &label->label;
7629         }
7630
7631         label = get_entity(symbol, NAMESPACE_LABEL);
7632         /* if we found a label in the same function, then we already created the
7633          * declaration */
7634         if (label != NULL
7635                         && label->base.parent_scope == &current_function->parameters) {
7636                 return &label->label;
7637         }
7638
7639         /* otherwise we need to create a new one */
7640         label               = allocate_entity_zero(ENTITY_LABEL);
7641         label->base.namespc = NAMESPACE_LABEL;
7642         label->base.symbol  = symbol;
7643
7644         label_push(label);
7645
7646         return &label->label;
7647 }
7648
7649 /**
7650  * Parses a GNU && label address expression.
7651  */
7652 static expression_t *parse_label_address(void)
7653 {
7654         source_position_t source_position = token.source_position;
7655         eat(T_ANDAND);
7656         if (token.type != T_IDENTIFIER) {
7657                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
7658                 goto end_error;
7659         }
7660         symbol_t *symbol = token.v.symbol;
7661         next_token();
7662
7663         label_t *label       = get_label(symbol);
7664         label->used          = true;
7665         label->address_taken = true;
7666
7667         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
7668         expression->base.source_position = source_position;
7669
7670         /* label address is threaten as a void pointer */
7671         expression->base.type           = type_void_ptr;
7672         expression->label_address.label = label;
7673         return expression;
7674 end_error:
7675         return create_invalid_expression();
7676 }
7677
7678 /**
7679  * Parse a microsoft __noop expression.
7680  */
7681 static expression_t *parse_noop_expression(void)
7682 {
7683         /* the result is a (int)0 */
7684         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
7685         cnst->base.type            = type_int;
7686         cnst->conste.v.int_value   = 0;
7687         cnst->conste.is_ms_noop    = true;
7688
7689         eat(T___noop);
7690
7691         if (token.type == '(') {
7692                 /* parse arguments */
7693                 eat('(');
7694                 add_anchor_token(')');
7695                 add_anchor_token(',');
7696
7697                 if (token.type != ')') {
7698                         while (true) {
7699                                 (void)parse_assignment_expression();
7700                                 if (token.type != ',')
7701                                         break;
7702                                 next_token();
7703                         }
7704                 }
7705         }
7706         rem_anchor_token(',');
7707         rem_anchor_token(')');
7708         expect(')', end_error);
7709
7710 end_error:
7711         return cnst;
7712 }
7713
7714 /**
7715  * Parses a primary expression.
7716  */
7717 static expression_t *parse_primary_expression(void)
7718 {
7719         switch (token.type) {
7720                 case T_false:                    return parse_bool_const(false);
7721                 case T_true:                     return parse_bool_const(true);
7722                 case T_INTEGER:                  return parse_int_const();
7723                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
7724                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
7725                 case T_FLOATINGPOINT:            return parse_float_const();
7726                 case T_STRING_LITERAL:
7727                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
7728                 case T_IDENTIFIER:               return parse_reference();
7729                 case T___FUNCTION__:
7730                 case T___func__:                 return parse_function_keyword();
7731                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
7732                 case T___FUNCSIG__:              return parse_funcsig_keyword();
7733                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
7734                 case T___builtin_offsetof:       return parse_offsetof();
7735                 case T___builtin_va_start:       return parse_va_start();
7736                 case T___builtin_va_arg:         return parse_va_arg();
7737                 case T___builtin_expect:
7738                 case T___builtin_alloca:
7739                 case T___builtin_inf:
7740                 case T___builtin_inff:
7741                 case T___builtin_infl:
7742                 case T___builtin_nan:
7743                 case T___builtin_nanf:
7744                 case T___builtin_nanl:
7745                 case T___builtin_huge_val:
7746                 case T___builtin_va_end:         return parse_builtin_symbol();
7747                 case T___builtin_isgreater:
7748                 case T___builtin_isgreaterequal:
7749                 case T___builtin_isless:
7750                 case T___builtin_islessequal:
7751                 case T___builtin_islessgreater:
7752                 case T___builtin_isunordered:    return parse_compare_builtin();
7753                 case T___builtin_constant_p:     return parse_builtin_constant();
7754                 case T___builtin_prefetch:       return parse_builtin_prefetch();
7755                 case T__assume:                  return parse_assume();
7756                 case T_ANDAND:
7757                         if (GNU_MODE)
7758                                 return parse_label_address();
7759                         break;
7760
7761                 case '(':                        return parse_parenthesized_expression();
7762                 case T___noop:                   return parse_noop_expression();
7763         }
7764
7765         errorf(HERE, "unexpected token %K, expected an expression", &token);
7766         return create_invalid_expression();
7767 }
7768
7769 /**
7770  * Check if the expression has the character type and issue a warning then.
7771  */
7772 static void check_for_char_index_type(const expression_t *expression)
7773 {
7774         type_t       *const type      = expression->base.type;
7775         const type_t *const base_type = skip_typeref(type);
7776
7777         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
7778                         warning.char_subscripts) {
7779                 warningf(&expression->base.source_position,
7780                          "array subscript has type '%T'", type);
7781         }
7782 }
7783
7784 static expression_t *parse_array_expression(expression_t *left)
7785 {
7786         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
7787
7788         eat('[');
7789         add_anchor_token(']');
7790
7791         expression_t *inside = parse_expression();
7792
7793         type_t *const orig_type_left   = left->base.type;
7794         type_t *const orig_type_inside = inside->base.type;
7795
7796         type_t *const type_left   = skip_typeref(orig_type_left);
7797         type_t *const type_inside = skip_typeref(orig_type_inside);
7798
7799         type_t                    *return_type;
7800         array_access_expression_t *array_access = &expression->array_access;
7801         if (is_type_pointer(type_left)) {
7802                 return_type             = type_left->pointer.points_to;
7803                 array_access->array_ref = left;
7804                 array_access->index     = inside;
7805                 check_for_char_index_type(inside);
7806         } else if (is_type_pointer(type_inside)) {
7807                 return_type             = type_inside->pointer.points_to;
7808                 array_access->array_ref = inside;
7809                 array_access->index     = left;
7810                 array_access->flipped   = true;
7811                 check_for_char_index_type(left);
7812         } else {
7813                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
7814                         errorf(HERE,
7815                                 "array access on object with non-pointer types '%T', '%T'",
7816                                 orig_type_left, orig_type_inside);
7817                 }
7818                 return_type             = type_error_type;
7819                 array_access->array_ref = left;
7820                 array_access->index     = inside;
7821         }
7822
7823         expression->base.type = automatic_type_conversion(return_type);
7824
7825         rem_anchor_token(']');
7826         expect(']', end_error);
7827 end_error:
7828         return expression;
7829 }
7830
7831 static expression_t *parse_typeprop(expression_kind_t const kind)
7832 {
7833         expression_t  *tp_expression = allocate_expression_zero(kind);
7834         tp_expression->base.type     = type_size_t;
7835
7836         eat(kind == EXPR_SIZEOF ? T_sizeof : T___alignof__);
7837
7838         /* we only refer to a type property, mark this case */
7839         bool old     = in_type_prop;
7840         in_type_prop = true;
7841
7842         type_t       *orig_type;
7843         expression_t *expression;
7844         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
7845                 next_token();
7846                 add_anchor_token(')');
7847                 orig_type = parse_typename();
7848                 rem_anchor_token(')');
7849                 expect(')', end_error);
7850
7851                 if (token.type == '{') {
7852                         /* It was not sizeof(type) after all.  It is sizeof of an expression
7853                          * starting with a compound literal */
7854                         expression = parse_compound_literal(orig_type);
7855                         goto typeprop_expression;
7856                 }
7857         } else {
7858                 expression = parse_sub_expression(PREC_UNARY);
7859
7860 typeprop_expression:
7861                 tp_expression->typeprop.tp_expression = expression;
7862
7863                 orig_type = revert_automatic_type_conversion(expression);
7864                 expression->base.type = orig_type;
7865         }
7866
7867         tp_expression->typeprop.type   = orig_type;
7868         type_t const* const type       = skip_typeref(orig_type);
7869         char   const* const wrong_type =
7870                 is_type_incomplete(type)    ? "incomplete"          :
7871                 type->kind == TYPE_FUNCTION ? "function designator" :
7872                 type->kind == TYPE_BITFIELD ? "bitfield"            :
7873                 NULL;
7874         if (wrong_type != NULL) {
7875                 char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7876                 errorf(&tp_expression->base.source_position,
7877                                 "operand of %s expression must not be of %s type '%T'",
7878                                 what, wrong_type, orig_type);
7879         }
7880
7881 end_error:
7882         in_type_prop = old;
7883         return tp_expression;
7884 }
7885
7886 static expression_t *parse_sizeof(void)
7887 {
7888         return parse_typeprop(EXPR_SIZEOF);
7889 }
7890
7891 static expression_t *parse_alignof(void)
7892 {
7893         return parse_typeprop(EXPR_ALIGNOF);
7894 }
7895
7896 static expression_t *parse_select_expression(expression_t *compound)
7897 {
7898         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
7899         select->select.compound = compound;
7900
7901         assert(token.type == '.' || token.type == T_MINUSGREATER);
7902         bool is_pointer = (token.type == T_MINUSGREATER);
7903         next_token();
7904
7905         if (token.type != T_IDENTIFIER) {
7906                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
7907                 return select;
7908         }
7909         symbol_t *symbol = token.v.symbol;
7910         next_token();
7911
7912         type_t *const orig_type = compound->base.type;
7913         type_t *const type      = skip_typeref(orig_type);
7914
7915         type_t *type_left;
7916         bool    saw_error = false;
7917         if (is_type_pointer(type)) {
7918                 if (!is_pointer) {
7919                         errorf(HERE,
7920                                "request for member '%Y' in something not a struct or union, but '%T'",
7921                                symbol, orig_type);
7922                         saw_error = true;
7923                 }
7924                 type_left = skip_typeref(type->pointer.points_to);
7925         } else {
7926                 if (is_pointer && is_type_valid(type)) {
7927                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7928                         saw_error = true;
7929                 }
7930                 type_left = type;
7931         }
7932
7933         entity_t *entry;
7934         if (type_left->kind == TYPE_COMPOUND_STRUCT ||
7935             type_left->kind == TYPE_COMPOUND_UNION) {
7936                 compound_t *compound = type_left->compound.compound;
7937
7938                 if (!compound->complete) {
7939                         errorf(HERE, "request for member '%Y' of incomplete type '%T'",
7940                                symbol, type_left);
7941                         goto create_error_entry;
7942                 }
7943
7944                 entry = find_compound_entry(compound, symbol);
7945                 if (entry == NULL) {
7946                         errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
7947                         goto create_error_entry;
7948                 }
7949         } else {
7950                 if (is_type_valid(type_left) && !saw_error) {
7951                         errorf(HERE,
7952                                "request for member '%Y' in something not a struct or union, but '%T'",
7953                                symbol, type_left);
7954                 }
7955 create_error_entry:
7956                 entry = create_error_entity(symbol, ENTITY_COMPOUND_MEMBER);
7957         }
7958
7959         assert(is_declaration(entry));
7960         select->select.compound_entry = entry;
7961
7962         type_t *entry_type = entry->declaration.type;
7963         type_t *res_type
7964                 = get_qualified_type(entry_type, type_left->base.qualifiers);
7965
7966         /* we always do the auto-type conversions; the & and sizeof parser contains
7967          * code to revert this! */
7968         select->base.type = automatic_type_conversion(res_type);
7969
7970         type_t *skipped = skip_typeref(res_type);
7971         if (skipped->kind == TYPE_BITFIELD) {
7972                 select->base.type = skipped->bitfield.base_type;
7973         }
7974
7975         return select;
7976 }
7977
7978 static void check_call_argument(const function_parameter_t *parameter,
7979                                 call_argument_t *argument, unsigned pos)
7980 {
7981         type_t         *expected_type      = parameter->type;
7982         type_t         *expected_type_skip = skip_typeref(expected_type);
7983         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
7984         expression_t   *arg_expr           = argument->expression;
7985         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
7986
7987         /* handle transparent union gnu extension */
7988         if (is_type_union(expected_type_skip)
7989                         && (expected_type_skip->base.modifiers
7990                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
7991                 compound_t *union_decl  = expected_type_skip->compound.compound;
7992                 type_t     *best_type   = NULL;
7993                 entity_t   *entry       = union_decl->members.entities;
7994                 for ( ; entry != NULL; entry = entry->base.next) {
7995                         assert(is_declaration(entry));
7996                         type_t *decl_type = entry->declaration.type;
7997                         error = semantic_assign(decl_type, arg_expr);
7998                         if (error == ASSIGN_ERROR_INCOMPATIBLE
7999                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
8000                                 continue;
8001
8002                         if (error == ASSIGN_SUCCESS) {
8003                                 best_type = decl_type;
8004                         } else if (best_type == NULL) {
8005                                 best_type = decl_type;
8006                         }
8007                 }
8008
8009                 if (best_type != NULL) {
8010                         expected_type = best_type;
8011                 }
8012         }
8013
8014         error                = semantic_assign(expected_type, arg_expr);
8015         argument->expression = create_implicit_cast(argument->expression,
8016                                                     expected_type);
8017
8018         if (error != ASSIGN_SUCCESS) {
8019                 /* report exact scope in error messages (like "in argument 3") */
8020                 char buf[64];
8021                 snprintf(buf, sizeof(buf), "call argument %u", pos);
8022                 report_assign_error(error, expected_type, arg_expr,     buf,
8023                                                         &arg_expr->base.source_position);
8024         } else if (warning.traditional || warning.conversion) {
8025                 type_t *const promoted_type = get_default_promoted_type(arg_type);
8026                 if (!types_compatible(expected_type_skip, promoted_type) &&
8027                     !types_compatible(expected_type_skip, type_void_ptr) &&
8028                     !types_compatible(type_void_ptr,      promoted_type)) {
8029                         /* Deliberately show the skipped types in this warning */
8030                         warningf(&arg_expr->base.source_position,
8031                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
8032                                 pos, expected_type_skip, promoted_type);
8033                 }
8034         }
8035 }
8036
8037 /**
8038  * Parse a call expression, ie. expression '( ... )'.
8039  *
8040  * @param expression  the function address
8041  */
8042 static expression_t *parse_call_expression(expression_t *expression)
8043 {
8044         expression_t      *result = allocate_expression_zero(EXPR_CALL);
8045         call_expression_t *call   = &result->call;
8046         call->function            = expression;
8047
8048         type_t *const orig_type = expression->base.type;
8049         type_t *const type      = skip_typeref(orig_type);
8050
8051         function_type_t *function_type = NULL;
8052         if (is_type_pointer(type)) {
8053                 type_t *const to_type = skip_typeref(type->pointer.points_to);
8054
8055                 if (is_type_function(to_type)) {
8056                         function_type   = &to_type->function;
8057                         call->base.type = function_type->return_type;
8058                 }
8059         }
8060
8061         if (function_type == NULL && is_type_valid(type)) {
8062                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
8063         }
8064
8065         /* parse arguments */
8066         eat('(');
8067         add_anchor_token(')');
8068         add_anchor_token(',');
8069
8070         if (token.type != ')') {
8071                 call_argument_t *last_argument = NULL;
8072
8073                 while (true) {
8074                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
8075
8076                         argument->expression = parse_assignment_expression();
8077                         if (last_argument == NULL) {
8078                                 call->arguments = argument;
8079                         } else {
8080                                 last_argument->next = argument;
8081                         }
8082                         last_argument = argument;
8083
8084                         if (token.type != ',')
8085                                 break;
8086                         next_token();
8087                 }
8088         }
8089         rem_anchor_token(',');
8090         rem_anchor_token(')');
8091         expect(')', end_error);
8092
8093         if (function_type == NULL)
8094                 return result;
8095
8096         function_parameter_t *parameter = function_type->parameters;
8097         call_argument_t      *argument  = call->arguments;
8098         if (!function_type->unspecified_parameters) {
8099                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
8100                                 parameter = parameter->next, argument = argument->next) {
8101                         check_call_argument(parameter, argument, ++pos);
8102                 }
8103
8104                 if (parameter != NULL) {
8105                         errorf(HERE, "too few arguments to function '%E'", expression);
8106                 } else if (argument != NULL && !function_type->variadic) {
8107                         errorf(HERE, "too many arguments to function '%E'", expression);
8108                 }
8109         }
8110
8111         /* do default promotion */
8112         for (; argument != NULL; argument = argument->next) {
8113                 type_t *type = argument->expression->base.type;
8114
8115                 type = get_default_promoted_type(type);
8116
8117                 argument->expression
8118                         = create_implicit_cast(argument->expression, type);
8119         }
8120
8121         check_format(&result->call);
8122
8123         if (warning.aggregate_return &&
8124             is_type_compound(skip_typeref(function_type->return_type))) {
8125                 warningf(&result->base.source_position,
8126                          "function call has aggregate value");
8127         }
8128
8129 end_error:
8130         return result;
8131 }
8132
8133 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
8134
8135 static bool same_compound_type(const type_t *type1, const type_t *type2)
8136 {
8137         return
8138                 is_type_compound(type1) &&
8139                 type1->kind == type2->kind &&
8140                 type1->compound.compound == type2->compound.compound;
8141 }
8142
8143 static expression_t const *get_reference_address(expression_t const *expr)
8144 {
8145         bool regular_take_address = true;
8146         for (;;) {
8147                 if (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8148                         expr = expr->unary.value;
8149                 } else {
8150                         regular_take_address = false;
8151                 }
8152
8153                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8154                         break;
8155
8156                 expr = expr->unary.value;
8157         }
8158
8159         if (expr->kind != EXPR_REFERENCE)
8160                 return NULL;
8161
8162         /* special case for functions which are automatically converted to a
8163          * pointer to function without an extra TAKE_ADDRESS operation */
8164         if (!regular_take_address &&
8165                         expr->reference.entity->kind != ENTITY_FUNCTION) {
8166                 return NULL;
8167         }
8168
8169         return expr;
8170 }
8171
8172 static void warn_reference_address_as_bool(expression_t const* expr)
8173 {
8174         if (!warning.address)
8175                 return;
8176
8177         expr = get_reference_address(expr);
8178         if (expr != NULL) {
8179                 warningf(&expr->base.source_position,
8180                          "the address of '%Y' will always evaluate as 'true'",
8181                          expr->reference.entity->base.symbol);
8182         }
8183 }
8184
8185 static void semantic_condition(expression_t const *const expr,
8186                                char const *const context)
8187 {
8188         type_t *const type = skip_typeref(expr->base.type);
8189         if (is_type_scalar(type)) {
8190                 warn_reference_address_as_bool(expr);
8191         } else if (is_type_valid(type)) {
8192                 errorf(&expr->base.source_position,
8193                                 "%s must have scalar type", context);
8194         }
8195 }
8196
8197 /**
8198  * Parse a conditional expression, ie. 'expression ? ... : ...'.
8199  *
8200  * @param expression  the conditional expression
8201  */
8202 static expression_t *parse_conditional_expression(expression_t *expression)
8203 {
8204         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
8205
8206         conditional_expression_t *conditional = &result->conditional;
8207         conditional->condition                = expression;
8208
8209         eat('?');
8210         add_anchor_token(':');
8211
8212         /* §6.5.15:2  The first operand shall have scalar type. */
8213         semantic_condition(expression, "condition of conditional operator");
8214
8215         expression_t *true_expression = expression;
8216         bool          gnu_cond = false;
8217         if (GNU_MODE && token.type == ':') {
8218                 gnu_cond = true;
8219         } else {
8220                 true_expression = parse_expression();
8221         }
8222         rem_anchor_token(':');
8223         expect(':', end_error);
8224         expression_t *false_expression =
8225                 parse_sub_expression(c_mode & _CXX ? PREC_ASSIGNMENT : PREC_CONDITIONAL);
8226
8227         type_t *const orig_true_type  = true_expression->base.type;
8228         type_t *const orig_false_type = false_expression->base.type;
8229         type_t *const true_type       = skip_typeref(orig_true_type);
8230         type_t *const false_type      = skip_typeref(orig_false_type);
8231
8232         /* 6.5.15.3 */
8233         type_t *result_type;
8234         if (is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8235                         is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
8236                 /* ISO/IEC 14882:1998(E) §5.16:2 */
8237                 if (true_expression->kind == EXPR_UNARY_THROW) {
8238                         result_type = false_type;
8239                 } else if (false_expression->kind == EXPR_UNARY_THROW) {
8240                         result_type = true_type;
8241                 } else {
8242                         if (warning.other && (
8243                                                 !is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8244                                                 !is_type_atomic(false_type, ATOMIC_TYPE_VOID)
8245                                         )) {
8246                                 warningf(&conditional->base.source_position,
8247                                                 "ISO C forbids conditional expression with only one void side");
8248                         }
8249                         result_type = type_void;
8250                 }
8251         } else if (is_type_arithmetic(true_type)
8252                    && is_type_arithmetic(false_type)) {
8253                 result_type = semantic_arithmetic(true_type, false_type);
8254
8255                 true_expression  = create_implicit_cast(true_expression, result_type);
8256                 false_expression = create_implicit_cast(false_expression, result_type);
8257
8258                 conditional->true_expression  = true_expression;
8259                 conditional->false_expression = false_expression;
8260                 conditional->base.type        = result_type;
8261         } else if (same_compound_type(true_type, false_type)) {
8262                 /* just take 1 of the 2 types */
8263                 result_type = true_type;
8264         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
8265                 type_t *pointer_type;
8266                 type_t *other_type;
8267                 expression_t *other_expression;
8268                 if (is_type_pointer(true_type) &&
8269                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
8270                         pointer_type     = true_type;
8271                         other_type       = false_type;
8272                         other_expression = false_expression;
8273                 } else {
8274                         pointer_type     = false_type;
8275                         other_type       = true_type;
8276                         other_expression = true_expression;
8277                 }
8278
8279                 if (is_null_pointer_constant(other_expression)) {
8280                         result_type = pointer_type;
8281                 } else if (is_type_pointer(other_type)) {
8282                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
8283                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
8284
8285                         type_t *to;
8286                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
8287                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
8288                                 to = type_void;
8289                         } else if (types_compatible(get_unqualified_type(to1),
8290                                                     get_unqualified_type(to2))) {
8291                                 to = to1;
8292                         } else {
8293                                 if (warning.other) {
8294                                         warningf(&conditional->base.source_position,
8295                                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
8296                                                         true_type, false_type);
8297                                 }
8298                                 to = type_void;
8299                         }
8300
8301                         type_t *const type =
8302                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
8303                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
8304                 } else if (is_type_integer(other_type)) {
8305                         if (warning.other) {
8306                                 warningf(&conditional->base.source_position,
8307                                                 "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
8308                         }
8309                         result_type = pointer_type;
8310                 } else {
8311                         if (is_type_valid(other_type)) {
8312                                 type_error_incompatible("while parsing conditional",
8313                                                 &expression->base.source_position, true_type, false_type);
8314                         }
8315                         result_type = type_error_type;
8316                 }
8317         } else {
8318                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
8319                         type_error_incompatible("while parsing conditional",
8320                                                 &conditional->base.source_position, true_type,
8321                                                 false_type);
8322                 }
8323                 result_type = type_error_type;
8324         }
8325
8326         conditional->true_expression
8327                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
8328         conditional->false_expression
8329                 = create_implicit_cast(false_expression, result_type);
8330         conditional->base.type = result_type;
8331         return result;
8332 end_error:
8333         return create_invalid_expression();
8334 }
8335
8336 /**
8337  * Parse an extension expression.
8338  */
8339 static expression_t *parse_extension(void)
8340 {
8341         eat(T___extension__);
8342
8343         bool old_gcc_extension   = in_gcc_extension;
8344         in_gcc_extension         = true;
8345         expression_t *expression = parse_sub_expression(PREC_UNARY);
8346         in_gcc_extension         = old_gcc_extension;
8347         return expression;
8348 }
8349
8350 /**
8351  * Parse a __builtin_classify_type() expression.
8352  */
8353 static expression_t *parse_builtin_classify_type(void)
8354 {
8355         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
8356         result->base.type    = type_int;
8357
8358         eat(T___builtin_classify_type);
8359
8360         expect('(', end_error);
8361         add_anchor_token(')');
8362         expression_t *expression = parse_expression();
8363         rem_anchor_token(')');
8364         expect(')', end_error);
8365         result->classify_type.type_expression = expression;
8366
8367         return result;
8368 end_error:
8369         return create_invalid_expression();
8370 }
8371
8372 /**
8373  * Parse a delete expression
8374  * ISO/IEC 14882:1998(E) §5.3.5
8375  */
8376 static expression_t *parse_delete(void)
8377 {
8378         expression_t *const result = allocate_expression_zero(EXPR_UNARY_DELETE);
8379         result->base.type          = type_void;
8380
8381         eat(T_delete);
8382
8383         if (token.type == '[') {
8384                 next_token();
8385                 result->kind = EXPR_UNARY_DELETE_ARRAY;
8386                 expect(']', end_error);
8387 end_error:;
8388         }
8389
8390         expression_t *const value = parse_sub_expression(PREC_CAST);
8391         result->unary.value = value;
8392
8393         type_t *const type = skip_typeref(value->base.type);
8394         if (!is_type_pointer(type)) {
8395                 errorf(&value->base.source_position,
8396                                 "operand of delete must have pointer type");
8397         } else if (warning.other &&
8398                         is_type_atomic(skip_typeref(type->pointer.points_to), ATOMIC_TYPE_VOID)) {
8399                 warningf(&value->base.source_position,
8400                                 "deleting 'void*' is undefined");
8401         }
8402
8403         return result;
8404 }
8405
8406 /**
8407  * Parse a throw expression
8408  * ISO/IEC 14882:1998(E) §15:1
8409  */
8410 static expression_t *parse_throw(void)
8411 {
8412         expression_t *const result = allocate_expression_zero(EXPR_UNARY_THROW);
8413         result->base.type          = type_void;
8414
8415         eat(T_throw);
8416
8417         expression_t *value = NULL;
8418         switch (token.type) {
8419                 EXPRESSION_START {
8420                         value = parse_assignment_expression();
8421                         /* ISO/IEC 14882:1998(E) §15.1:3 */
8422                         type_t *const orig_type = value->base.type;
8423                         type_t *const type      = skip_typeref(orig_type);
8424                         if (is_type_incomplete(type)) {
8425                                 errorf(&value->base.source_position,
8426                                                 "cannot throw object of incomplete type '%T'", orig_type);
8427                         } else if (is_type_pointer(type)) {
8428                                 type_t *const points_to = skip_typeref(type->pointer.points_to);
8429                                 if (is_type_incomplete(points_to) &&
8430                                                 !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8431                                         errorf(&value->base.source_position,
8432                                                         "cannot throw pointer to incomplete type '%T'", orig_type);
8433                                 }
8434                         }
8435                 }
8436
8437                 default:
8438                         break;
8439         }
8440         result->unary.value = value;
8441
8442         return result;
8443 }
8444
8445 static bool check_pointer_arithmetic(const source_position_t *source_position,
8446                                      type_t *pointer_type,
8447                                      type_t *orig_pointer_type)
8448 {
8449         type_t *points_to = pointer_type->pointer.points_to;
8450         points_to = skip_typeref(points_to);
8451
8452         if (is_type_incomplete(points_to)) {
8453                 if (!GNU_MODE || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8454                         errorf(source_position,
8455                                "arithmetic with pointer to incomplete type '%T' not allowed",
8456                                orig_pointer_type);
8457                         return false;
8458                 } else if (warning.pointer_arith) {
8459                         warningf(source_position,
8460                                  "pointer of type '%T' used in arithmetic",
8461                                  orig_pointer_type);
8462                 }
8463         } else if (is_type_function(points_to)) {
8464                 if (!GNU_MODE) {
8465                         errorf(source_position,
8466                                "arithmetic with pointer to function type '%T' not allowed",
8467                                orig_pointer_type);
8468                         return false;
8469                 } else if (warning.pointer_arith) {
8470                         warningf(source_position,
8471                                  "pointer to a function '%T' used in arithmetic",
8472                                  orig_pointer_type);
8473                 }
8474         }
8475         return true;
8476 }
8477
8478 static bool is_lvalue(const expression_t *expression)
8479 {
8480         /* TODO: doesn't seem to be consistent with §6.3.2.1 (1) */
8481         switch (expression->kind) {
8482         case EXPR_REFERENCE:
8483         case EXPR_ARRAY_ACCESS:
8484         case EXPR_SELECT:
8485         case EXPR_UNARY_DEREFERENCE:
8486                 return true;
8487
8488         default: {
8489           type_t *type = skip_typeref(expression->base.type);
8490           return
8491                 /* ISO/IEC 14882:1998(E) §3.10:3 */
8492                 is_type_reference(type) ||
8493                 /* Claim it is an lvalue, if the type is invalid.  There was a parse
8494                  * error before, which maybe prevented properly recognizing it as
8495                  * lvalue. */
8496                 !is_type_valid(type);
8497         }
8498         }
8499 }
8500
8501 static void semantic_incdec(unary_expression_t *expression)
8502 {
8503         type_t *const orig_type = expression->value->base.type;
8504         type_t *const type      = skip_typeref(orig_type);
8505         if (is_type_pointer(type)) {
8506                 if (!check_pointer_arithmetic(&expression->base.source_position,
8507                                               type, orig_type)) {
8508                         return;
8509                 }
8510         } else if (!is_type_real(type) && is_type_valid(type)) {
8511                 /* TODO: improve error message */
8512                 errorf(&expression->base.source_position,
8513                        "operation needs an arithmetic or pointer type");
8514                 return;
8515         }
8516         if (!is_lvalue(expression->value)) {
8517                 /* TODO: improve error message */
8518                 errorf(&expression->base.source_position, "lvalue required as operand");
8519         }
8520         expression->base.type = orig_type;
8521 }
8522
8523 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
8524 {
8525         type_t *const orig_type = expression->value->base.type;
8526         type_t *const type      = skip_typeref(orig_type);
8527         if (!is_type_arithmetic(type)) {
8528                 if (is_type_valid(type)) {
8529                         /* TODO: improve error message */
8530                         errorf(&expression->base.source_position,
8531                                 "operation needs an arithmetic type");
8532                 }
8533                 return;
8534         }
8535
8536         expression->base.type = orig_type;
8537 }
8538
8539 static void semantic_unexpr_plus(unary_expression_t *expression)
8540 {
8541         semantic_unexpr_arithmetic(expression);
8542         if (warning.traditional)
8543                 warningf(&expression->base.source_position,
8544                         "traditional C rejects the unary plus operator");
8545 }
8546
8547 static void semantic_not(unary_expression_t *expression)
8548 {
8549         /* §6.5.3.3:1  The operand [...] of the ! operator, scalar type. */
8550         semantic_condition(expression->value, "operand of !");
8551         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8552 }
8553
8554 static void semantic_unexpr_integer(unary_expression_t *expression)
8555 {
8556         type_t *const orig_type = expression->value->base.type;
8557         type_t *const type      = skip_typeref(orig_type);
8558         if (!is_type_integer(type)) {
8559                 if (is_type_valid(type)) {
8560                         errorf(&expression->base.source_position,
8561                                "operand of ~ must be of integer type");
8562                 }
8563                 return;
8564         }
8565
8566         expression->base.type = orig_type;
8567 }
8568
8569 static void semantic_dereference(unary_expression_t *expression)
8570 {
8571         type_t *const orig_type = expression->value->base.type;
8572         type_t *const type      = skip_typeref(orig_type);
8573         if (!is_type_pointer(type)) {
8574                 if (is_type_valid(type)) {
8575                         errorf(&expression->base.source_position,
8576                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
8577                 }
8578                 return;
8579         }
8580
8581         type_t *result_type   = type->pointer.points_to;
8582         result_type           = automatic_type_conversion(result_type);
8583         expression->base.type = result_type;
8584 }
8585
8586 /**
8587  * Record that an address is taken (expression represents an lvalue).
8588  *
8589  * @param expression       the expression
8590  * @param may_be_register  if true, the expression might be an register
8591  */
8592 static void set_address_taken(expression_t *expression, bool may_be_register)
8593 {
8594         if (expression->kind != EXPR_REFERENCE)
8595                 return;
8596
8597         entity_t *const entity = expression->reference.entity;
8598
8599         if (entity->kind != ENTITY_VARIABLE && entity->kind != ENTITY_PARAMETER)
8600                 return;
8601
8602         if (entity->declaration.storage_class == STORAGE_CLASS_REGISTER
8603                         && !may_be_register) {
8604                 errorf(&expression->base.source_position,
8605                                 "address of register %s '%Y' requested",
8606                                 get_entity_kind_name(entity->kind),     entity->base.symbol);
8607         }
8608
8609         if (entity->kind == ENTITY_VARIABLE) {
8610                 entity->variable.address_taken = true;
8611         } else {
8612                 assert(entity->kind == ENTITY_PARAMETER);
8613                 entity->parameter.address_taken = true;
8614         }
8615 }
8616
8617 /**
8618  * Check the semantic of the address taken expression.
8619  */
8620 static void semantic_take_addr(unary_expression_t *expression)
8621 {
8622         expression_t *value = expression->value;
8623         value->base.type    = revert_automatic_type_conversion(value);
8624
8625         type_t *orig_type = value->base.type;
8626         type_t *type      = skip_typeref(orig_type);
8627         if (!is_type_valid(type))
8628                 return;
8629
8630         /* §6.5.3.2 */
8631         if (!is_lvalue(value)) {
8632                 errorf(&expression->base.source_position, "'&' requires an lvalue");
8633         }
8634         if (type->kind == TYPE_BITFIELD) {
8635                 errorf(&expression->base.source_position,
8636                        "'&' not allowed on object with bitfield type '%T'",
8637                        type);
8638         }
8639
8640         set_address_taken(value, false);
8641
8642         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
8643 }
8644
8645 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc) \
8646 static expression_t *parse_##unexpression_type(void)                         \
8647 {                                                                            \
8648         expression_t *unary_expression                                           \
8649                 = allocate_expression_zero(unexpression_type);                       \
8650         eat(token_type);                                                         \
8651         unary_expression->unary.value = parse_sub_expression(PREC_UNARY);        \
8652                                                                                  \
8653         sfunc(&unary_expression->unary);                                         \
8654                                                                                  \
8655         return unary_expression;                                                 \
8656 }
8657
8658 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
8659                                semantic_unexpr_arithmetic)
8660 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
8661                                semantic_unexpr_plus)
8662 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
8663                                semantic_not)
8664 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
8665                                semantic_dereference)
8666 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
8667                                semantic_take_addr)
8668 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
8669                                semantic_unexpr_integer)
8670 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
8671                                semantic_incdec)
8672 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
8673                                semantic_incdec)
8674
8675 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
8676                                                sfunc)                         \
8677 static expression_t *parse_##unexpression_type(expression_t *left)            \
8678 {                                                                             \
8679         expression_t *unary_expression                                            \
8680                 = allocate_expression_zero(unexpression_type);                        \
8681         eat(token_type);                                                          \
8682         unary_expression->unary.value = left;                                     \
8683                                                                                   \
8684         sfunc(&unary_expression->unary);                                          \
8685                                                                               \
8686         return unary_expression;                                                  \
8687 }
8688
8689 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
8690                                        EXPR_UNARY_POSTFIX_INCREMENT,
8691                                        semantic_incdec)
8692 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
8693                                        EXPR_UNARY_POSTFIX_DECREMENT,
8694                                        semantic_incdec)
8695
8696 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
8697 {
8698         /* TODO: handle complex + imaginary types */
8699
8700         type_left  = get_unqualified_type(type_left);
8701         type_right = get_unqualified_type(type_right);
8702
8703         /* § 6.3.1.8 Usual arithmetic conversions */
8704         if (type_left == type_long_double || type_right == type_long_double) {
8705                 return type_long_double;
8706         } else if (type_left == type_double || type_right == type_double) {
8707                 return type_double;
8708         } else if (type_left == type_float || type_right == type_float) {
8709                 return type_float;
8710         }
8711
8712         type_left  = promote_integer(type_left);
8713         type_right = promote_integer(type_right);
8714
8715         if (type_left == type_right)
8716                 return type_left;
8717
8718         bool const signed_left  = is_type_signed(type_left);
8719         bool const signed_right = is_type_signed(type_right);
8720         int const  rank_left    = get_rank(type_left);
8721         int const  rank_right   = get_rank(type_right);
8722
8723         if (signed_left == signed_right)
8724                 return rank_left >= rank_right ? type_left : type_right;
8725
8726         int     s_rank;
8727         int     u_rank;
8728         type_t *s_type;
8729         type_t *u_type;
8730         if (signed_left) {
8731                 s_rank = rank_left;
8732                 s_type = type_left;
8733                 u_rank = rank_right;
8734                 u_type = type_right;
8735         } else {
8736                 s_rank = rank_right;
8737                 s_type = type_right;
8738                 u_rank = rank_left;
8739                 u_type = type_left;
8740         }
8741
8742         if (u_rank >= s_rank)
8743                 return u_type;
8744
8745         /* casting rank to atomic_type_kind is a bit hacky, but makes things
8746          * easier here... */
8747         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
8748                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
8749                 return s_type;
8750
8751         switch (s_rank) {
8752                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
8753                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
8754                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
8755
8756                 default: panic("invalid atomic type");
8757         }
8758 }
8759
8760 /**
8761  * Check the semantic restrictions for a binary expression.
8762  */
8763 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
8764 {
8765         expression_t *const left            = expression->left;
8766         expression_t *const right           = expression->right;
8767         type_t       *const orig_type_left  = left->base.type;
8768         type_t       *const orig_type_right = right->base.type;
8769         type_t       *const type_left       = skip_typeref(orig_type_left);
8770         type_t       *const type_right      = skip_typeref(orig_type_right);
8771
8772         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8773                 /* TODO: improve error message */
8774                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8775                         errorf(&expression->base.source_position,
8776                                "operation needs arithmetic types");
8777                 }
8778                 return;
8779         }
8780
8781         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8782         expression->left      = create_implicit_cast(left, arithmetic_type);
8783         expression->right     = create_implicit_cast(right, arithmetic_type);
8784         expression->base.type = arithmetic_type;
8785 }
8786
8787 static void warn_div_by_zero(binary_expression_t const *const expression)
8788 {
8789         if (!warning.div_by_zero ||
8790             !is_type_integer(expression->base.type))
8791                 return;
8792
8793         expression_t const *const right = expression->right;
8794         /* The type of the right operand can be different for /= */
8795         if (is_type_integer(right->base.type) &&
8796             is_constant_expression(right)     &&
8797             fold_constant(right) == 0) {
8798                 warningf(&expression->base.source_position, "division by zero");
8799         }
8800 }
8801
8802 /**
8803  * Check the semantic restrictions for a div/mod expression.
8804  */
8805 static void semantic_divmod_arithmetic(binary_expression_t *expression) {
8806         semantic_binexpr_arithmetic(expression);
8807         warn_div_by_zero(expression);
8808 }
8809
8810 static void semantic_shift_op(binary_expression_t *expression)
8811 {
8812         expression_t *const left            = expression->left;
8813         expression_t *const right           = expression->right;
8814         type_t       *const orig_type_left  = left->base.type;
8815         type_t       *const orig_type_right = right->base.type;
8816         type_t       *      type_left       = skip_typeref(orig_type_left);
8817         type_t       *      type_right      = skip_typeref(orig_type_right);
8818
8819         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8820                 /* TODO: improve error message */
8821                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8822                         errorf(&expression->base.source_position,
8823                                "operands of shift operation must have integer types");
8824                 }
8825                 return;
8826         }
8827
8828         type_left  = promote_integer(type_left);
8829         type_right = promote_integer(type_right);
8830
8831         expression->left      = create_implicit_cast(left, type_left);
8832         expression->right     = create_implicit_cast(right, type_right);
8833         expression->base.type = type_left;
8834 }
8835
8836 static void semantic_add(binary_expression_t *expression)
8837 {
8838         expression_t *const left            = expression->left;
8839         expression_t *const right           = expression->right;
8840         type_t       *const orig_type_left  = left->base.type;
8841         type_t       *const orig_type_right = right->base.type;
8842         type_t       *const type_left       = skip_typeref(orig_type_left);
8843         type_t       *const type_right      = skip_typeref(orig_type_right);
8844
8845         /* § 6.5.6 */
8846         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8847                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8848                 expression->left  = create_implicit_cast(left, arithmetic_type);
8849                 expression->right = create_implicit_cast(right, arithmetic_type);
8850                 expression->base.type = arithmetic_type;
8851                 return;
8852         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8853                 check_pointer_arithmetic(&expression->base.source_position,
8854                                          type_left, orig_type_left);
8855                 expression->base.type = type_left;
8856         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
8857                 check_pointer_arithmetic(&expression->base.source_position,
8858                                          type_right, orig_type_right);
8859                 expression->base.type = type_right;
8860         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8861                 errorf(&expression->base.source_position,
8862                        "invalid operands to binary + ('%T', '%T')",
8863                        orig_type_left, orig_type_right);
8864         }
8865 }
8866
8867 static void semantic_sub(binary_expression_t *expression)
8868 {
8869         expression_t            *const left            = expression->left;
8870         expression_t            *const right           = expression->right;
8871         type_t                  *const orig_type_left  = left->base.type;
8872         type_t                  *const orig_type_right = right->base.type;
8873         type_t                  *const type_left       = skip_typeref(orig_type_left);
8874         type_t                  *const type_right      = skip_typeref(orig_type_right);
8875         source_position_t const *const pos             = &expression->base.source_position;
8876
8877         /* § 5.6.5 */
8878         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8879                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8880                 expression->left        = create_implicit_cast(left, arithmetic_type);
8881                 expression->right       = create_implicit_cast(right, arithmetic_type);
8882                 expression->base.type =  arithmetic_type;
8883                 return;
8884         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8885                 check_pointer_arithmetic(&expression->base.source_position,
8886                                          type_left, orig_type_left);
8887                 expression->base.type = type_left;
8888         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8889                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
8890                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
8891                 if (!types_compatible(unqual_left, unqual_right)) {
8892                         errorf(pos,
8893                                "subtracting pointers to incompatible types '%T' and '%T'",
8894                                orig_type_left, orig_type_right);
8895                 } else if (!is_type_object(unqual_left)) {
8896                         if (!is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
8897                                 errorf(pos, "subtracting pointers to non-object types '%T'",
8898                                        orig_type_left);
8899                         } else if (warning.other) {
8900                                 warningf(pos, "subtracting pointers to void");
8901                         }
8902                 }
8903                 expression->base.type = type_ptrdiff_t;
8904         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8905                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
8906                        orig_type_left, orig_type_right);
8907         }
8908 }
8909
8910 static void warn_string_literal_address(expression_t const* expr)
8911 {
8912         while (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8913                 expr = expr->unary.value;
8914                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8915                         return;
8916                 expr = expr->unary.value;
8917         }
8918
8919         if (expr->kind == EXPR_STRING_LITERAL ||
8920             expr->kind == EXPR_WIDE_STRING_LITERAL) {
8921                 warningf(&expr->base.source_position,
8922                         "comparison with string literal results in unspecified behaviour");
8923         }
8924 }
8925
8926 /**
8927  * Check the semantics of comparison expressions.
8928  *
8929  * @param expression   The expression to check.
8930  */
8931 static void semantic_comparison(binary_expression_t *expression)
8932 {
8933         expression_t *left  = expression->left;
8934         expression_t *right = expression->right;
8935
8936         if (warning.address) {
8937                 warn_string_literal_address(left);
8938                 warn_string_literal_address(right);
8939
8940                 expression_t const* const func_left = get_reference_address(left);
8941                 if (func_left != NULL && is_null_pointer_constant(right)) {
8942                         warningf(&expression->base.source_position,
8943                                  "the address of '%Y' will never be NULL",
8944                                  func_left->reference.entity->base.symbol);
8945                 }
8946
8947                 expression_t const* const func_right = get_reference_address(right);
8948                 if (func_right != NULL && is_null_pointer_constant(right)) {
8949                         warningf(&expression->base.source_position,
8950                                  "the address of '%Y' will never be NULL",
8951                                  func_right->reference.entity->base.symbol);
8952                 }
8953         }
8954
8955         type_t *orig_type_left  = left->base.type;
8956         type_t *orig_type_right = right->base.type;
8957         type_t *type_left       = skip_typeref(orig_type_left);
8958         type_t *type_right      = skip_typeref(orig_type_right);
8959
8960         /* TODO non-arithmetic types */
8961         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8962                 /* test for signed vs unsigned compares */
8963                 if (warning.sign_compare &&
8964                     (expression->base.kind != EXPR_BINARY_EQUAL &&
8965                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
8966                     (is_type_signed(type_left) != is_type_signed(type_right))) {
8967
8968                         /* check if 1 of the operands is a constant, in this case we just
8969                          * check wether we can safely represent the resulting constant in
8970                          * the type of the other operand. */
8971                         expression_t *const_expr = NULL;
8972                         expression_t *other_expr = NULL;
8973
8974                         if (is_constant_expression(left)) {
8975                                 const_expr = left;
8976                                 other_expr = right;
8977                         } else if (is_constant_expression(right)) {
8978                                 const_expr = right;
8979                                 other_expr = left;
8980                         }
8981
8982                         if (const_expr != NULL) {
8983                                 type_t *other_type = skip_typeref(other_expr->base.type);
8984                                 long    val        = fold_constant(const_expr);
8985                                 /* TODO: check if val can be represented by other_type */
8986                                 (void) other_type;
8987                                 (void) val;
8988                         }
8989                         warningf(&expression->base.source_position,
8990                                  "comparison between signed and unsigned");
8991                 }
8992                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8993                 expression->left        = create_implicit_cast(left, arithmetic_type);
8994                 expression->right       = create_implicit_cast(right, arithmetic_type);
8995                 expression->base.type   = arithmetic_type;
8996                 if (warning.float_equal &&
8997                     (expression->base.kind == EXPR_BINARY_EQUAL ||
8998                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
8999                     is_type_float(arithmetic_type)) {
9000                         warningf(&expression->base.source_position,
9001                                  "comparing floating point with == or != is unsafe");
9002                 }
9003         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
9004                 /* TODO check compatibility */
9005         } else if (is_type_pointer(type_left)) {
9006                 expression->right = create_implicit_cast(right, type_left);
9007         } else if (is_type_pointer(type_right)) {
9008                 expression->left = create_implicit_cast(left, type_right);
9009         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9010                 type_error_incompatible("invalid operands in comparison",
9011                                         &expression->base.source_position,
9012                                         type_left, type_right);
9013         }
9014         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9015 }
9016
9017 /**
9018  * Checks if a compound type has constant fields.
9019  */
9020 static bool has_const_fields(const compound_type_t *type)
9021 {
9022         compound_t *compound = type->compound;
9023         entity_t   *entry    = compound->members.entities;
9024
9025         for (; entry != NULL; entry = entry->base.next) {
9026                 if (!is_declaration(entry))
9027                         continue;
9028
9029                 const type_t *decl_type = skip_typeref(entry->declaration.type);
9030                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
9031                         return true;
9032         }
9033
9034         return false;
9035 }
9036
9037 static bool is_valid_assignment_lhs(expression_t const* const left)
9038 {
9039         type_t *const orig_type_left = revert_automatic_type_conversion(left);
9040         type_t *const type_left      = skip_typeref(orig_type_left);
9041
9042         if (!is_lvalue(left)) {
9043                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
9044                        left);
9045                 return false;
9046         }
9047
9048         if (left->kind == EXPR_REFERENCE
9049                         && left->reference.entity->kind == ENTITY_FUNCTION) {
9050                 errorf(HERE, "cannot assign to function '%E'", left);
9051                 return false;
9052         }
9053
9054         if (is_type_array(type_left)) {
9055                 errorf(HERE, "cannot assign to array '%E'", left);
9056                 return false;
9057         }
9058         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
9059                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
9060                        orig_type_left);
9061                 return false;
9062         }
9063         if (is_type_incomplete(type_left)) {
9064                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
9065                        left, orig_type_left);
9066                 return false;
9067         }
9068         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
9069                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
9070                        left, orig_type_left);
9071                 return false;
9072         }
9073
9074         return true;
9075 }
9076
9077 static void semantic_arithmetic_assign(binary_expression_t *expression)
9078 {
9079         expression_t *left            = expression->left;
9080         expression_t *right           = expression->right;
9081         type_t       *orig_type_left  = left->base.type;
9082         type_t       *orig_type_right = right->base.type;
9083
9084         if (!is_valid_assignment_lhs(left))
9085                 return;
9086
9087         type_t *type_left  = skip_typeref(orig_type_left);
9088         type_t *type_right = skip_typeref(orig_type_right);
9089
9090         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
9091                 /* TODO: improve error message */
9092                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
9093                         errorf(&expression->base.source_position,
9094                                "operation needs arithmetic types");
9095                 }
9096                 return;
9097         }
9098
9099         /* combined instructions are tricky. We can't create an implicit cast on
9100          * the left side, because we need the uncasted form for the store.
9101          * The ast2firm pass has to know that left_type must be right_type
9102          * for the arithmetic operation and create a cast by itself */
9103         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
9104         expression->right       = create_implicit_cast(right, arithmetic_type);
9105         expression->base.type   = type_left;
9106 }
9107
9108 static void semantic_divmod_assign(binary_expression_t *expression)
9109 {
9110         semantic_arithmetic_assign(expression);
9111         warn_div_by_zero(expression);
9112 }
9113
9114 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
9115 {
9116         expression_t *const left            = expression->left;
9117         expression_t *const right           = expression->right;
9118         type_t       *const orig_type_left  = left->base.type;
9119         type_t       *const orig_type_right = right->base.type;
9120         type_t       *const type_left       = skip_typeref(orig_type_left);
9121         type_t       *const type_right      = skip_typeref(orig_type_right);
9122
9123         if (!is_valid_assignment_lhs(left))
9124                 return;
9125
9126         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
9127                 /* combined instructions are tricky. We can't create an implicit cast on
9128                  * the left side, because we need the uncasted form for the store.
9129                  * The ast2firm pass has to know that left_type must be right_type
9130                  * for the arithmetic operation and create a cast by itself */
9131                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
9132                 expression->right     = create_implicit_cast(right, arithmetic_type);
9133                 expression->base.type = type_left;
9134         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
9135                 check_pointer_arithmetic(&expression->base.source_position,
9136                                          type_left, orig_type_left);
9137                 expression->base.type = type_left;
9138         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9139                 errorf(&expression->base.source_position,
9140                        "incompatible types '%T' and '%T' in assignment",
9141                        orig_type_left, orig_type_right);
9142         }
9143 }
9144
9145 /**
9146  * Check the semantic restrictions of a logical expression.
9147  */
9148 static void semantic_logical_op(binary_expression_t *expression)
9149 {
9150         /* §6.5.13:2  Each of the operands shall have scalar type.
9151          * §6.5.14:2  Each of the operands shall have scalar type. */
9152         semantic_condition(expression->left,   "left operand of logical operator");
9153         semantic_condition(expression->right, "right operand of logical operator");
9154         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9155 }
9156
9157 /**
9158  * Check the semantic restrictions of a binary assign expression.
9159  */
9160 static void semantic_binexpr_assign(binary_expression_t *expression)
9161 {
9162         expression_t *left           = expression->left;
9163         type_t       *orig_type_left = left->base.type;
9164
9165         if (!is_valid_assignment_lhs(left))
9166                 return;
9167
9168         assign_error_t error = semantic_assign(orig_type_left, expression->right);
9169         report_assign_error(error, orig_type_left, expression->right,
9170                         "assignment", &left->base.source_position);
9171         expression->right = create_implicit_cast(expression->right, orig_type_left);
9172         expression->base.type = orig_type_left;
9173 }
9174
9175 /**
9176  * Determine if the outermost operation (or parts thereof) of the given
9177  * expression has no effect in order to generate a warning about this fact.
9178  * Therefore in some cases this only examines some of the operands of the
9179  * expression (see comments in the function and examples below).
9180  * Examples:
9181  *   f() + 23;    // warning, because + has no effect
9182  *   x || f();    // no warning, because x controls execution of f()
9183  *   x ? y : f(); // warning, because y has no effect
9184  *   (void)x;     // no warning to be able to suppress the warning
9185  * This function can NOT be used for an "expression has definitely no effect"-
9186  * analysis. */
9187 static bool expression_has_effect(const expression_t *const expr)
9188 {
9189         switch (expr->kind) {
9190                 case EXPR_UNKNOWN:                   break;
9191                 case EXPR_INVALID:                   return true; /* do NOT warn */
9192                 case EXPR_REFERENCE:                 return false;
9193                 case EXPR_REFERENCE_ENUM_VALUE:      return false;
9194                 /* suppress the warning for microsoft __noop operations */
9195                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
9196                 case EXPR_CHARACTER_CONSTANT:        return false;
9197                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
9198                 case EXPR_STRING_LITERAL:            return false;
9199                 case EXPR_WIDE_STRING_LITERAL:       return false;
9200                 case EXPR_LABEL_ADDRESS:             return false;
9201
9202                 case EXPR_CALL: {
9203                         const call_expression_t *const call = &expr->call;
9204                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
9205                                 return true;
9206
9207                         switch (call->function->builtin_symbol.symbol->ID) {
9208                                 case T___builtin_va_end: return true;
9209                                 default:                 return false;
9210                         }
9211                 }
9212
9213                 /* Generate the warning if either the left or right hand side of a
9214                  * conditional expression has no effect */
9215                 case EXPR_CONDITIONAL: {
9216                         const conditional_expression_t *const cond = &expr->conditional;
9217                         return
9218                                 expression_has_effect(cond->true_expression) &&
9219                                 expression_has_effect(cond->false_expression);
9220                 }
9221
9222                 case EXPR_SELECT:                    return false;
9223                 case EXPR_ARRAY_ACCESS:              return false;
9224                 case EXPR_SIZEOF:                    return false;
9225                 case EXPR_CLASSIFY_TYPE:             return false;
9226                 case EXPR_ALIGNOF:                   return false;
9227
9228                 case EXPR_FUNCNAME:                  return false;
9229                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
9230                 case EXPR_BUILTIN_CONSTANT_P:        return false;
9231                 case EXPR_BUILTIN_PREFETCH:          return true;
9232                 case EXPR_OFFSETOF:                  return false;
9233                 case EXPR_VA_START:                  return true;
9234                 case EXPR_VA_ARG:                    return true;
9235                 case EXPR_STATEMENT:                 return true; // TODO
9236                 case EXPR_COMPOUND_LITERAL:          return false;
9237
9238                 case EXPR_UNARY_NEGATE:              return false;
9239                 case EXPR_UNARY_PLUS:                return false;
9240                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
9241                 case EXPR_UNARY_NOT:                 return false;
9242                 case EXPR_UNARY_DEREFERENCE:         return false;
9243                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
9244                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
9245                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
9246                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
9247                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
9248
9249                 /* Treat void casts as if they have an effect in order to being able to
9250                  * suppress the warning */
9251                 case EXPR_UNARY_CAST: {
9252                         type_t *const type = skip_typeref(expr->base.type);
9253                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
9254                 }
9255
9256                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
9257                 case EXPR_UNARY_ASSUME:              return true;
9258                 case EXPR_UNARY_DELETE:              return true;
9259                 case EXPR_UNARY_DELETE_ARRAY:        return true;
9260                 case EXPR_UNARY_THROW:               return true;
9261
9262                 case EXPR_BINARY_ADD:                return false;
9263                 case EXPR_BINARY_SUB:                return false;
9264                 case EXPR_BINARY_MUL:                return false;
9265                 case EXPR_BINARY_DIV:                return false;
9266                 case EXPR_BINARY_MOD:                return false;
9267                 case EXPR_BINARY_EQUAL:              return false;
9268                 case EXPR_BINARY_NOTEQUAL:           return false;
9269                 case EXPR_BINARY_LESS:               return false;
9270                 case EXPR_BINARY_LESSEQUAL:          return false;
9271                 case EXPR_BINARY_GREATER:            return false;
9272                 case EXPR_BINARY_GREATEREQUAL:       return false;
9273                 case EXPR_BINARY_BITWISE_AND:        return false;
9274                 case EXPR_BINARY_BITWISE_OR:         return false;
9275                 case EXPR_BINARY_BITWISE_XOR:        return false;
9276                 case EXPR_BINARY_SHIFTLEFT:          return false;
9277                 case EXPR_BINARY_SHIFTRIGHT:         return false;
9278                 case EXPR_BINARY_ASSIGN:             return true;
9279                 case EXPR_BINARY_MUL_ASSIGN:         return true;
9280                 case EXPR_BINARY_DIV_ASSIGN:         return true;
9281                 case EXPR_BINARY_MOD_ASSIGN:         return true;
9282                 case EXPR_BINARY_ADD_ASSIGN:         return true;
9283                 case EXPR_BINARY_SUB_ASSIGN:         return true;
9284                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
9285                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
9286                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
9287                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
9288                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
9289
9290                 /* Only examine the right hand side of && and ||, because the left hand
9291                  * side already has the effect of controlling the execution of the right
9292                  * hand side */
9293                 case EXPR_BINARY_LOGICAL_AND:
9294                 case EXPR_BINARY_LOGICAL_OR:
9295                 /* Only examine the right hand side of a comma expression, because the left
9296                  * hand side has a separate warning */
9297                 case EXPR_BINARY_COMMA:
9298                         return expression_has_effect(expr->binary.right);
9299
9300                 case EXPR_BINARY_ISGREATER:          return false;
9301                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
9302                 case EXPR_BINARY_ISLESS:             return false;
9303                 case EXPR_BINARY_ISLESSEQUAL:        return false;
9304                 case EXPR_BINARY_ISLESSGREATER:      return false;
9305                 case EXPR_BINARY_ISUNORDERED:        return false;
9306         }
9307
9308         internal_errorf(HERE, "unexpected expression");
9309 }
9310
9311 static void semantic_comma(binary_expression_t *expression)
9312 {
9313         if (warning.unused_value) {
9314                 const expression_t *const left = expression->left;
9315                 if (!expression_has_effect(left)) {
9316                         warningf(&left->base.source_position,
9317                                  "left-hand operand of comma expression has no effect");
9318                 }
9319         }
9320         expression->base.type = expression->right->base.type;
9321 }
9322
9323 /**
9324  * @param prec_r precedence of the right operand
9325  */
9326 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, prec_r, sfunc) \
9327 static expression_t *parse_##binexpression_type(expression_t *left)          \
9328 {                                                                            \
9329         expression_t *binexpr = allocate_expression_zero(binexpression_type);    \
9330         binexpr->binary.left  = left;                                            \
9331         eat(token_type);                                                         \
9332                                                                              \
9333         expression_t *right = parse_sub_expression(prec_r);                      \
9334                                                                              \
9335         binexpr->binary.right = right;                                           \
9336         sfunc(&binexpr->binary);                                                 \
9337                                                                              \
9338         return binexpr;                                                          \
9339 }
9340
9341 CREATE_BINEXPR_PARSER('*',                    EXPR_BINARY_MUL,                PREC_CAST,           semantic_binexpr_arithmetic)
9342 CREATE_BINEXPR_PARSER('/',                    EXPR_BINARY_DIV,                PREC_CAST,           semantic_divmod_arithmetic)
9343 CREATE_BINEXPR_PARSER('%',                    EXPR_BINARY_MOD,                PREC_CAST,           semantic_divmod_arithmetic)
9344 CREATE_BINEXPR_PARSER('+',                    EXPR_BINARY_ADD,                PREC_MULTIPLICATIVE, semantic_add)
9345 CREATE_BINEXPR_PARSER('-',                    EXPR_BINARY_SUB,                PREC_MULTIPLICATIVE, semantic_sub)
9346 CREATE_BINEXPR_PARSER(T_LESSLESS,             EXPR_BINARY_SHIFTLEFT,          PREC_ADDITIVE,       semantic_shift_op)
9347 CREATE_BINEXPR_PARSER(T_GREATERGREATER,       EXPR_BINARY_SHIFTRIGHT,         PREC_ADDITIVE,       semantic_shift_op)
9348 CREATE_BINEXPR_PARSER('<',                    EXPR_BINARY_LESS,               PREC_SHIFT,          semantic_comparison)
9349 CREATE_BINEXPR_PARSER('>',                    EXPR_BINARY_GREATER,            PREC_SHIFT,          semantic_comparison)
9350 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,          PREC_SHIFT,          semantic_comparison)
9351 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,       PREC_SHIFT,          semantic_comparison)
9352 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,           PREC_RELATIONAL,     semantic_comparison)
9353 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,              PREC_RELATIONAL,     semantic_comparison)
9354 CREATE_BINEXPR_PARSER('&',                    EXPR_BINARY_BITWISE_AND,        PREC_EQUALITY,       semantic_binexpr_arithmetic)
9355 CREATE_BINEXPR_PARSER('^',                    EXPR_BINARY_BITWISE_XOR,        PREC_AND,            semantic_binexpr_arithmetic)
9356 CREATE_BINEXPR_PARSER('|',                    EXPR_BINARY_BITWISE_OR,         PREC_XOR,            semantic_binexpr_arithmetic)
9357 CREATE_BINEXPR_PARSER(T_ANDAND,               EXPR_BINARY_LOGICAL_AND,        PREC_OR,             semantic_logical_op)
9358 CREATE_BINEXPR_PARSER(T_PIPEPIPE,             EXPR_BINARY_LOGICAL_OR,         PREC_LOGICAL_AND,    semantic_logical_op)
9359 CREATE_BINEXPR_PARSER('=',                    EXPR_BINARY_ASSIGN,             PREC_ASSIGNMENT,     semantic_binexpr_assign)
9360 CREATE_BINEXPR_PARSER(T_PLUSEQUAL,            EXPR_BINARY_ADD_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9361 CREATE_BINEXPR_PARSER(T_MINUSEQUAL,           EXPR_BINARY_SUB_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9362 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL,        EXPR_BINARY_MUL_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9363 CREATE_BINEXPR_PARSER(T_SLASHEQUAL,           EXPR_BINARY_DIV_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9364 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL,         EXPR_BINARY_MOD_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9365 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL,        EXPR_BINARY_SHIFTLEFT_ASSIGN,   PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9366 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL,  EXPR_BINARY_SHIFTRIGHT_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9367 CREATE_BINEXPR_PARSER(T_ANDEQUAL,             EXPR_BINARY_BITWISE_AND_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9368 CREATE_BINEXPR_PARSER(T_PIPEEQUAL,            EXPR_BINARY_BITWISE_OR_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9369 CREATE_BINEXPR_PARSER(T_CARETEQUAL,           EXPR_BINARY_BITWISE_XOR_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9370 CREATE_BINEXPR_PARSER(',',                    EXPR_BINARY_COMMA,              PREC_ASSIGNMENT,     semantic_comma)
9371
9372
9373 static expression_t *parse_sub_expression(precedence_t precedence)
9374 {
9375         if (token.type < 0) {
9376                 return expected_expression_error();
9377         }
9378
9379         expression_parser_function_t *parser
9380                 = &expression_parsers[token.type];
9381         source_position_t             source_position = token.source_position;
9382         expression_t                 *left;
9383
9384         if (parser->parser != NULL) {
9385                 left = parser->parser();
9386         } else {
9387                 left = parse_primary_expression();
9388         }
9389         assert(left != NULL);
9390         left->base.source_position = source_position;
9391
9392         while (true) {
9393                 if (token.type < 0) {
9394                         return expected_expression_error();
9395                 }
9396
9397                 parser = &expression_parsers[token.type];
9398                 if (parser->infix_parser == NULL)
9399                         break;
9400                 if (parser->infix_precedence < precedence)
9401                         break;
9402
9403                 left = parser->infix_parser(left);
9404
9405                 assert(left != NULL);
9406                 assert(left->kind != EXPR_UNKNOWN);
9407                 left->base.source_position = source_position;
9408         }
9409
9410         return left;
9411 }
9412
9413 /**
9414  * Parse an expression.
9415  */
9416 static expression_t *parse_expression(void)
9417 {
9418         return parse_sub_expression(PREC_EXPRESSION);
9419 }
9420
9421 /**
9422  * Register a parser for a prefix-like operator.
9423  *
9424  * @param parser      the parser function
9425  * @param token_type  the token type of the prefix token
9426  */
9427 static void register_expression_parser(parse_expression_function parser,
9428                                        int token_type)
9429 {
9430         expression_parser_function_t *entry = &expression_parsers[token_type];
9431
9432         if (entry->parser != NULL) {
9433                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9434                 panic("trying to register multiple expression parsers for a token");
9435         }
9436         entry->parser = parser;
9437 }
9438
9439 /**
9440  * Register a parser for an infix operator with given precedence.
9441  *
9442  * @param parser      the parser function
9443  * @param token_type  the token type of the infix operator
9444  * @param precedence  the precedence of the operator
9445  */
9446 static void register_infix_parser(parse_expression_infix_function parser,
9447                 int token_type, unsigned precedence)
9448 {
9449         expression_parser_function_t *entry = &expression_parsers[token_type];
9450
9451         if (entry->infix_parser != NULL) {
9452                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9453                 panic("trying to register multiple infix expression parsers for a "
9454                       "token");
9455         }
9456         entry->infix_parser     = parser;
9457         entry->infix_precedence = precedence;
9458 }
9459
9460 /**
9461  * Initialize the expression parsers.
9462  */
9463 static void init_expression_parsers(void)
9464 {
9465         memset(&expression_parsers, 0, sizeof(expression_parsers));
9466
9467         register_infix_parser(parse_array_expression,               '[',                    PREC_POSTFIX);
9468         register_infix_parser(parse_call_expression,                '(',                    PREC_POSTFIX);
9469         register_infix_parser(parse_select_expression,              '.',                    PREC_POSTFIX);
9470         register_infix_parser(parse_select_expression,              T_MINUSGREATER,         PREC_POSTFIX);
9471         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,   T_PLUSPLUS,             PREC_POSTFIX);
9472         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,   T_MINUSMINUS,           PREC_POSTFIX);
9473         register_infix_parser(parse_EXPR_BINARY_MUL,                '*',                    PREC_MULTIPLICATIVE);
9474         register_infix_parser(parse_EXPR_BINARY_DIV,                '/',                    PREC_MULTIPLICATIVE);
9475         register_infix_parser(parse_EXPR_BINARY_MOD,                '%',                    PREC_MULTIPLICATIVE);
9476         register_infix_parser(parse_EXPR_BINARY_ADD,                '+',                    PREC_ADDITIVE);
9477         register_infix_parser(parse_EXPR_BINARY_SUB,                '-',                    PREC_ADDITIVE);
9478         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,          T_LESSLESS,             PREC_SHIFT);
9479         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,         T_GREATERGREATER,       PREC_SHIFT);
9480         register_infix_parser(parse_EXPR_BINARY_LESS,               '<',                    PREC_RELATIONAL);
9481         register_infix_parser(parse_EXPR_BINARY_GREATER,            '>',                    PREC_RELATIONAL);
9482         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,          T_LESSEQUAL,            PREC_RELATIONAL);
9483         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL,       T_GREATEREQUAL,         PREC_RELATIONAL);
9484         register_infix_parser(parse_EXPR_BINARY_EQUAL,              T_EQUALEQUAL,           PREC_EQUALITY);
9485         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,           T_EXCLAMATIONMARKEQUAL, PREC_EQUALITY);
9486         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,        '&',                    PREC_AND);
9487         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,        '^',                    PREC_XOR);
9488         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,         '|',                    PREC_OR);
9489         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,        T_ANDAND,               PREC_LOGICAL_AND);
9490         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,         T_PIPEPIPE,             PREC_LOGICAL_OR);
9491         register_infix_parser(parse_conditional_expression,         '?',                    PREC_CONDITIONAL);
9492         register_infix_parser(parse_EXPR_BINARY_ASSIGN,             '=',                    PREC_ASSIGNMENT);
9493         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,         T_PLUSEQUAL,            PREC_ASSIGNMENT);
9494         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,         T_MINUSEQUAL,           PREC_ASSIGNMENT);
9495         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,         T_ASTERISKEQUAL,        PREC_ASSIGNMENT);
9496         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,         T_SLASHEQUAL,           PREC_ASSIGNMENT);
9497         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,         T_PERCENTEQUAL,         PREC_ASSIGNMENT);
9498         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,   T_LESSLESSEQUAL,        PREC_ASSIGNMENT);
9499         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,  T_GREATERGREATEREQUAL,  PREC_ASSIGNMENT);
9500         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN, T_ANDEQUAL,             PREC_ASSIGNMENT);
9501         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,  T_PIPEEQUAL,            PREC_ASSIGNMENT);
9502         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN, T_CARETEQUAL,           PREC_ASSIGNMENT);
9503         register_infix_parser(parse_EXPR_BINARY_COMMA,              ',',                    PREC_EXPRESSION);
9504
9505         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-');
9506         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+');
9507         register_expression_parser(parse_EXPR_UNARY_NOT,              '!');
9508         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~');
9509         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*');
9510         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&');
9511         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT, T_PLUSPLUS);
9512         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT, T_MINUSMINUS);
9513         register_expression_parser(parse_sizeof,                      T_sizeof);
9514         register_expression_parser(parse_alignof,                     T___alignof__);
9515         register_expression_parser(parse_extension,                   T___extension__);
9516         register_expression_parser(parse_builtin_classify_type,       T___builtin_classify_type);
9517         register_expression_parser(parse_delete,                      T_delete);
9518         register_expression_parser(parse_throw,                       T_throw);
9519 }
9520
9521 /**
9522  * Parse a asm statement arguments specification.
9523  */
9524 static asm_argument_t *parse_asm_arguments(bool is_out)
9525 {
9526         asm_argument_t  *result = NULL;
9527         asm_argument_t **anchor = &result;
9528
9529         while (token.type == T_STRING_LITERAL || token.type == '[') {
9530                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
9531                 memset(argument, 0, sizeof(argument[0]));
9532
9533                 if (token.type == '[') {
9534                         eat('[');
9535                         if (token.type != T_IDENTIFIER) {
9536                                 parse_error_expected("while parsing asm argument",
9537                                                      T_IDENTIFIER, NULL);
9538                                 return NULL;
9539                         }
9540                         argument->symbol = token.v.symbol;
9541
9542                         expect(']', end_error);
9543                 }
9544
9545                 argument->constraints = parse_string_literals();
9546                 expect('(', end_error);
9547                 add_anchor_token(')');
9548                 expression_t *expression = parse_expression();
9549                 rem_anchor_token(')');
9550                 if (is_out) {
9551                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
9552                          * change size or type representation (e.g. int -> long is ok, but
9553                          * int -> float is not) */
9554                         if (expression->kind == EXPR_UNARY_CAST) {
9555                                 type_t      *const type = expression->base.type;
9556                                 type_kind_t  const kind = type->kind;
9557                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
9558                                         unsigned flags;
9559                                         unsigned size;
9560                                         if (kind == TYPE_ATOMIC) {
9561                                                 atomic_type_kind_t const akind = type->atomic.akind;
9562                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9563                                                 size  = get_atomic_type_size(akind);
9564                                         } else {
9565                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9566                                                 size  = get_atomic_type_size(get_intptr_kind());
9567                                         }
9568
9569                                         do {
9570                                                 expression_t *const value      = expression->unary.value;
9571                                                 type_t       *const value_type = value->base.type;
9572                                                 type_kind_t   const value_kind = value_type->kind;
9573
9574                                                 unsigned value_flags;
9575                                                 unsigned value_size;
9576                                                 if (value_kind == TYPE_ATOMIC) {
9577                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
9578                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9579                                                         value_size  = get_atomic_type_size(value_akind);
9580                                                 } else if (value_kind == TYPE_POINTER) {
9581                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9582                                                         value_size  = get_atomic_type_size(get_intptr_kind());
9583                                                 } else {
9584                                                         break;
9585                                                 }
9586
9587                                                 if (value_flags != flags || value_size != size)
9588                                                         break;
9589
9590                                                 expression = value;
9591                                         } while (expression->kind == EXPR_UNARY_CAST);
9592                                 }
9593                         }
9594
9595                         if (!is_lvalue(expression)) {
9596                                 errorf(&expression->base.source_position,
9597                                        "asm output argument is not an lvalue");
9598                         }
9599
9600                         if (argument->constraints.begin[0] == '+')
9601                                 mark_vars_read(expression, NULL);
9602                 } else {
9603                         mark_vars_read(expression, NULL);
9604                 }
9605                 argument->expression = expression;
9606                 expect(')', end_error);
9607
9608                 set_address_taken(expression, true);
9609
9610                 *anchor = argument;
9611                 anchor  = &argument->next;
9612
9613                 if (token.type != ',')
9614                         break;
9615                 eat(',');
9616         }
9617
9618         return result;
9619 end_error:
9620         return NULL;
9621 }
9622
9623 /**
9624  * Parse a asm statement clobber specification.
9625  */
9626 static asm_clobber_t *parse_asm_clobbers(void)
9627 {
9628         asm_clobber_t *result = NULL;
9629         asm_clobber_t *last   = NULL;
9630
9631         while (token.type == T_STRING_LITERAL) {
9632                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
9633                 clobber->clobber       = parse_string_literals();
9634
9635                 if (last != NULL) {
9636                         last->next = clobber;
9637                 } else {
9638                         result = clobber;
9639                 }
9640                 last = clobber;
9641
9642                 if (token.type != ',')
9643                         break;
9644                 eat(',');
9645         }
9646
9647         return result;
9648 }
9649
9650 /**
9651  * Parse an asm statement.
9652  */
9653 static statement_t *parse_asm_statement(void)
9654 {
9655         statement_t     *statement     = allocate_statement_zero(STATEMENT_ASM);
9656         asm_statement_t *asm_statement = &statement->asms;
9657
9658         eat(T_asm);
9659
9660         if (token.type == T_volatile) {
9661                 next_token();
9662                 asm_statement->is_volatile = true;
9663         }
9664
9665         expect('(', end_error);
9666         add_anchor_token(')');
9667         add_anchor_token(':');
9668         asm_statement->asm_text = parse_string_literals();
9669
9670         if (token.type != ':') {
9671                 rem_anchor_token(':');
9672                 goto end_of_asm;
9673         }
9674         eat(':');
9675
9676         asm_statement->outputs = parse_asm_arguments(true);
9677         if (token.type != ':') {
9678                 rem_anchor_token(':');
9679                 goto end_of_asm;
9680         }
9681         eat(':');
9682
9683         asm_statement->inputs = parse_asm_arguments(false);
9684         if (token.type != ':') {
9685                 rem_anchor_token(':');
9686                 goto end_of_asm;
9687         }
9688         rem_anchor_token(':');
9689         eat(':');
9690
9691         asm_statement->clobbers = parse_asm_clobbers();
9692
9693 end_of_asm:
9694         rem_anchor_token(')');
9695         expect(')', end_error);
9696         expect(';', end_error);
9697
9698         if (asm_statement->outputs == NULL) {
9699                 /* GCC: An 'asm' instruction without any output operands will be treated
9700                  * identically to a volatile 'asm' instruction. */
9701                 asm_statement->is_volatile = true;
9702         }
9703
9704         return statement;
9705 end_error:
9706         return create_invalid_statement();
9707 }
9708
9709 /**
9710  * Parse a case statement.
9711  */
9712 static statement_t *parse_case_statement(void)
9713 {
9714         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9715         source_position_t *const pos       = &statement->base.source_position;
9716
9717         eat(T_case);
9718
9719         expression_t *const expression   = parse_expression();
9720         statement->case_label.expression = expression;
9721         if (!is_constant_expression(expression)) {
9722                 /* This check does not prevent the error message in all cases of an
9723                  * prior error while parsing the expression.  At least it catches the
9724                  * common case of a mistyped enum entry. */
9725                 if (is_type_valid(skip_typeref(expression->base.type))) {
9726                         errorf(pos, "case label does not reduce to an integer constant");
9727                 }
9728                 statement->case_label.is_bad = true;
9729         } else {
9730                 long const val = fold_constant(expression);
9731                 statement->case_label.first_case = val;
9732                 statement->case_label.last_case  = val;
9733         }
9734
9735         if (GNU_MODE) {
9736                 if (token.type == T_DOTDOTDOT) {
9737                         next_token();
9738                         expression_t *const end_range   = parse_expression();
9739                         statement->case_label.end_range = end_range;
9740                         if (!is_constant_expression(end_range)) {
9741                                 /* This check does not prevent the error message in all cases of an
9742                                  * prior error while parsing the expression.  At least it catches the
9743                                  * common case of a mistyped enum entry. */
9744                                 if (is_type_valid(skip_typeref(end_range->base.type))) {
9745                                         errorf(pos, "case range does not reduce to an integer constant");
9746                                 }
9747                                 statement->case_label.is_bad = true;
9748                         } else {
9749                                 long const val = fold_constant(end_range);
9750                                 statement->case_label.last_case = val;
9751
9752                                 if (warning.other && val < statement->case_label.first_case) {
9753                                         statement->case_label.is_empty_range = true;
9754                                         warningf(pos, "empty range specified");
9755                                 }
9756                         }
9757                 }
9758         }
9759
9760         PUSH_PARENT(statement);
9761
9762         expect(':', end_error);
9763 end_error:
9764
9765         if (current_switch != NULL) {
9766                 if (! statement->case_label.is_bad) {
9767                         /* Check for duplicate case values */
9768                         case_label_statement_t *c = &statement->case_label;
9769                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
9770                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
9771                                         continue;
9772
9773                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
9774                                         continue;
9775
9776                                 errorf(pos, "duplicate case value (previously used %P)",
9777                                        &l->base.source_position);
9778                                 break;
9779                         }
9780                 }
9781                 /* link all cases into the switch statement */
9782                 if (current_switch->last_case == NULL) {
9783                         current_switch->first_case      = &statement->case_label;
9784                 } else {
9785                         current_switch->last_case->next = &statement->case_label;
9786                 }
9787                 current_switch->last_case = &statement->case_label;
9788         } else {
9789                 errorf(pos, "case label not within a switch statement");
9790         }
9791
9792         statement_t *const inner_stmt = parse_statement();
9793         statement->case_label.statement = inner_stmt;
9794         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9795                 errorf(&inner_stmt->base.source_position, "declaration after case label");
9796         }
9797
9798         POP_PARENT;
9799         return statement;
9800 }
9801
9802 /**
9803  * Parse a default statement.
9804  */
9805 static statement_t *parse_default_statement(void)
9806 {
9807         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9808
9809         eat(T_default);
9810
9811         PUSH_PARENT(statement);
9812
9813         expect(':', end_error);
9814         if (current_switch != NULL) {
9815                 const case_label_statement_t *def_label = current_switch->default_label;
9816                 if (def_label != NULL) {
9817                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
9818                                &def_label->base.source_position);
9819                 } else {
9820                         current_switch->default_label = &statement->case_label;
9821
9822                         /* link all cases into the switch statement */
9823                         if (current_switch->last_case == NULL) {
9824                                 current_switch->first_case      = &statement->case_label;
9825                         } else {
9826                                 current_switch->last_case->next = &statement->case_label;
9827                         }
9828                         current_switch->last_case = &statement->case_label;
9829                 }
9830         } else {
9831                 errorf(&statement->base.source_position,
9832                         "'default' label not within a switch statement");
9833         }
9834
9835         statement_t *const inner_stmt = parse_statement();
9836         statement->case_label.statement = inner_stmt;
9837         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9838                 errorf(&inner_stmt->base.source_position, "declaration after default label");
9839         }
9840
9841         POP_PARENT;
9842         return statement;
9843 end_error:
9844         POP_PARENT;
9845         return create_invalid_statement();
9846 }
9847
9848 /**
9849  * Parse a label statement.
9850  */
9851 static statement_t *parse_label_statement(void)
9852 {
9853         assert(token.type == T_IDENTIFIER);
9854         symbol_t *symbol = token.v.symbol;
9855         label_t  *label  = get_label(symbol);
9856
9857         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
9858         statement->label.label       = label;
9859
9860         next_token();
9861
9862         PUSH_PARENT(statement);
9863
9864         /* if statement is already set then the label is defined twice,
9865          * otherwise it was just mentioned in a goto/local label declaration so far
9866          */
9867         if (label->statement != NULL) {
9868                 errorf(HERE, "duplicate label '%Y' (declared %P)",
9869                        symbol, &label->base.source_position);
9870         } else {
9871                 label->base.source_position = token.source_position;
9872                 label->statement            = statement;
9873         }
9874
9875         eat(':');
9876
9877         if (token.type == '}') {
9878                 /* TODO only warn? */
9879                 if (warning.other && false) {
9880                         warningf(HERE, "label at end of compound statement");
9881                         statement->label.statement = create_empty_statement();
9882                 } else {
9883                         errorf(HERE, "label at end of compound statement");
9884                         statement->label.statement = create_invalid_statement();
9885                 }
9886         } else if (token.type == ';') {
9887                 /* Eat an empty statement here, to avoid the warning about an empty
9888                  * statement after a label.  label:; is commonly used to have a label
9889                  * before a closing brace. */
9890                 statement->label.statement = create_empty_statement();
9891                 next_token();
9892         } else {
9893                 statement_t *const inner_stmt = parse_statement();
9894                 statement->label.statement = inner_stmt;
9895                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
9896                         errorf(&inner_stmt->base.source_position, "declaration after label");
9897                 }
9898         }
9899
9900         /* remember the labels in a list for later checking */
9901         *label_anchor = &statement->label;
9902         label_anchor  = &statement->label.next;
9903
9904         POP_PARENT;
9905         return statement;
9906 }
9907
9908 /**
9909  * Parse an if statement.
9910  */
9911 static statement_t *parse_if(void)
9912 {
9913         statement_t *statement = allocate_statement_zero(STATEMENT_IF);
9914
9915         eat(T_if);
9916
9917         PUSH_PARENT(statement);
9918
9919         add_anchor_token('{');
9920
9921         expect('(', end_error);
9922         add_anchor_token(')');
9923         expression_t *const expr = parse_expression();
9924         statement->ifs.condition = expr;
9925         /* §6.8.4.1:1  The controlling expression of an if statement shall have
9926          *             scalar type. */
9927         semantic_condition(expr, "condition of 'if'-statment");
9928         mark_vars_read(expr, NULL);
9929         rem_anchor_token(')');
9930         expect(')', end_error);
9931
9932 end_error:
9933         rem_anchor_token('{');
9934
9935         add_anchor_token(T_else);
9936         statement->ifs.true_statement = parse_statement();
9937         rem_anchor_token(T_else);
9938
9939         if (token.type == T_else) {
9940                 next_token();
9941                 statement->ifs.false_statement = parse_statement();
9942         }
9943
9944         POP_PARENT;
9945         return statement;
9946 }
9947
9948 /**
9949  * Check that all enums are handled in a switch.
9950  *
9951  * @param statement  the switch statement to check
9952  */
9953 static void check_enum_cases(const switch_statement_t *statement) {
9954         const type_t *type = skip_typeref(statement->expression->base.type);
9955         if (! is_type_enum(type))
9956                 return;
9957         const enum_type_t *enumt = &type->enumt;
9958
9959         /* if we have a default, no warnings */
9960         if (statement->default_label != NULL)
9961                 return;
9962
9963         /* FIXME: calculation of value should be done while parsing */
9964         /* TODO: quadratic algorithm here. Change to an n log n one */
9965         long            last_value = -1;
9966         const entity_t *entry      = enumt->enume->base.next;
9967         for (; entry != NULL && entry->kind == ENTITY_ENUM_VALUE;
9968              entry = entry->base.next) {
9969                 const expression_t *expression = entry->enum_value.value;
9970                 long                value      = expression != NULL ? fold_constant(expression) : last_value + 1;
9971                 bool                found      = false;
9972                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
9973                         if (l->expression == NULL)
9974                                 continue;
9975                         if (l->first_case <= value && value <= l->last_case) {
9976                                 found = true;
9977                                 break;
9978                         }
9979                 }
9980                 if (! found) {
9981                         warningf(&statement->base.source_position,
9982                                  "enumeration value '%Y' not handled in switch",
9983                                  entry->base.symbol);
9984                 }
9985                 last_value = value;
9986         }
9987 }
9988
9989 /**
9990  * Parse a switch statement.
9991  */
9992 static statement_t *parse_switch(void)
9993 {
9994         statement_t *statement = allocate_statement_zero(STATEMENT_SWITCH);
9995
9996         eat(T_switch);
9997
9998         PUSH_PARENT(statement);
9999
10000         expect('(', end_error);
10001         add_anchor_token(')');
10002         expression_t *const expr = parse_expression();
10003         mark_vars_read(expr, NULL);
10004         type_t       *      type = skip_typeref(expr->base.type);
10005         if (is_type_integer(type)) {
10006                 type = promote_integer(type);
10007                 if (warning.traditional) {
10008                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
10009                                 warningf(&expr->base.source_position,
10010                                         "'%T' switch expression not converted to '%T' in ISO C",
10011                                         type, type_int);
10012                         }
10013                 }
10014         } else if (is_type_valid(type)) {
10015                 errorf(&expr->base.source_position,
10016                        "switch quantity is not an integer, but '%T'", type);
10017                 type = type_error_type;
10018         }
10019         statement->switchs.expression = create_implicit_cast(expr, type);
10020         expect(')', end_error);
10021         rem_anchor_token(')');
10022
10023         switch_statement_t *rem = current_switch;
10024         current_switch          = &statement->switchs;
10025         statement->switchs.body = parse_statement();
10026         current_switch          = rem;
10027
10028         if (warning.switch_default &&
10029             statement->switchs.default_label == NULL) {
10030                 warningf(&statement->base.source_position, "switch has no default case");
10031         }
10032         if (warning.switch_enum)
10033                 check_enum_cases(&statement->switchs);
10034
10035         POP_PARENT;
10036         return statement;
10037 end_error:
10038         POP_PARENT;
10039         return create_invalid_statement();
10040 }
10041
10042 static statement_t *parse_loop_body(statement_t *const loop)
10043 {
10044         statement_t *const rem = current_loop;
10045         current_loop = loop;
10046
10047         statement_t *const body = parse_statement();
10048
10049         current_loop = rem;
10050         return body;
10051 }
10052
10053 /**
10054  * Parse a while statement.
10055  */
10056 static statement_t *parse_while(void)
10057 {
10058         statement_t *statement = allocate_statement_zero(STATEMENT_WHILE);
10059
10060         eat(T_while);
10061
10062         PUSH_PARENT(statement);
10063
10064         expect('(', end_error);
10065         add_anchor_token(')');
10066         expression_t *const cond = parse_expression();
10067         statement->whiles.condition = cond;
10068         /* §6.8.5:2    The controlling expression of an iteration statement shall
10069          *             have scalar type. */
10070         semantic_condition(cond, "condition of 'while'-statement");
10071         mark_vars_read(cond, NULL);
10072         rem_anchor_token(')');
10073         expect(')', end_error);
10074
10075         statement->whiles.body = parse_loop_body(statement);
10076
10077         POP_PARENT;
10078         return statement;
10079 end_error:
10080         POP_PARENT;
10081         return create_invalid_statement();
10082 }
10083
10084 /**
10085  * Parse a do statement.
10086  */
10087 static statement_t *parse_do(void)
10088 {
10089         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
10090
10091         eat(T_do);
10092
10093         PUSH_PARENT(statement);
10094
10095         add_anchor_token(T_while);
10096         statement->do_while.body = parse_loop_body(statement);
10097         rem_anchor_token(T_while);
10098
10099         expect(T_while, end_error);
10100         expect('(', end_error);
10101         add_anchor_token(')');
10102         expression_t *const cond = parse_expression();
10103         statement->do_while.condition = cond;
10104         /* §6.8.5:2    The controlling expression of an iteration statement shall
10105          *             have scalar type. */
10106         semantic_condition(cond, "condition of 'do-while'-statement");
10107         mark_vars_read(cond, NULL);
10108         rem_anchor_token(')');
10109         expect(')', end_error);
10110         expect(';', end_error);
10111
10112         POP_PARENT;
10113         return statement;
10114 end_error:
10115         POP_PARENT;
10116         return create_invalid_statement();
10117 }
10118
10119 /**
10120  * Parse a for statement.
10121  */
10122 static statement_t *parse_for(void)
10123 {
10124         statement_t *statement = allocate_statement_zero(STATEMENT_FOR);
10125
10126         eat(T_for);
10127
10128         expect('(', end_error1);
10129         add_anchor_token(')');
10130
10131         PUSH_PARENT(statement);
10132
10133         size_t const  top       = environment_top();
10134         scope_t      *old_scope = scope_push(&statement->fors.scope);
10135
10136         if (token.type == ';') {
10137                 next_token();
10138         } else if (is_declaration_specifier(&token, false)) {
10139                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10140         } else {
10141                 add_anchor_token(';');
10142                 expression_t *const init = parse_expression();
10143                 statement->fors.initialisation = init;
10144                 mark_vars_read(init, ENT_ANY);
10145                 if (warning.unused_value && !expression_has_effect(init)) {
10146                         warningf(&init->base.source_position,
10147                                         "initialisation of 'for'-statement has no effect");
10148                 }
10149                 rem_anchor_token(';');
10150                 expect(';', end_error2);
10151         }
10152
10153         if (token.type != ';') {
10154                 add_anchor_token(';');
10155                 expression_t *const cond = parse_expression();
10156                 statement->fors.condition = cond;
10157                 /* §6.8.5:2    The controlling expression of an iteration statement
10158                  *             shall have scalar type. */
10159                 semantic_condition(cond, "condition of 'for'-statement");
10160                 mark_vars_read(cond, NULL);
10161                 rem_anchor_token(';');
10162         }
10163         expect(';', end_error2);
10164         if (token.type != ')') {
10165                 expression_t *const step = parse_expression();
10166                 statement->fors.step = step;
10167                 mark_vars_read(step, ENT_ANY);
10168                 if (warning.unused_value && !expression_has_effect(step)) {
10169                         warningf(&step->base.source_position,
10170                                  "step of 'for'-statement has no effect");
10171                 }
10172         }
10173         expect(')', end_error2);
10174         rem_anchor_token(')');
10175         statement->fors.body = parse_loop_body(statement);
10176
10177         assert(current_scope == &statement->fors.scope);
10178         scope_pop(old_scope);
10179         environment_pop_to(top);
10180
10181         POP_PARENT;
10182         return statement;
10183
10184 end_error2:
10185         POP_PARENT;
10186         rem_anchor_token(')');
10187         assert(current_scope == &statement->fors.scope);
10188         scope_pop(old_scope);
10189         environment_pop_to(top);
10190         /* fallthrough */
10191
10192 end_error1:
10193         return create_invalid_statement();
10194 }
10195
10196 /**
10197  * Parse a goto statement.
10198  */
10199 static statement_t *parse_goto(void)
10200 {
10201         statement_t *statement = allocate_statement_zero(STATEMENT_GOTO);
10202         eat(T_goto);
10203
10204         if (GNU_MODE && token.type == '*') {
10205                 next_token();
10206                 expression_t *expression = parse_expression();
10207                 mark_vars_read(expression, NULL);
10208
10209                 /* Argh: although documentation says the expression must be of type void*,
10210                  * gcc accepts anything that can be casted into void* without error */
10211                 type_t *type = expression->base.type;
10212
10213                 if (type != type_error_type) {
10214                         if (!is_type_pointer(type) && !is_type_integer(type)) {
10215                                 errorf(&expression->base.source_position,
10216                                         "cannot convert to a pointer type");
10217                         } else if (warning.other && type != type_void_ptr) {
10218                                 warningf(&expression->base.source_position,
10219                                         "type of computed goto expression should be 'void*' not '%T'", type);
10220                         }
10221                         expression = create_implicit_cast(expression, type_void_ptr);
10222                 }
10223
10224                 statement->gotos.expression = expression;
10225         } else {
10226                 if (token.type != T_IDENTIFIER) {
10227                         if (GNU_MODE)
10228                                 parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
10229                         else
10230                                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
10231                         eat_until_anchor();
10232                         goto end_error;
10233                 }
10234                 symbol_t *symbol = token.v.symbol;
10235                 next_token();
10236
10237                 statement->gotos.label = get_label(symbol);
10238         }
10239
10240         /* remember the goto's in a list for later checking */
10241         *goto_anchor = &statement->gotos;
10242         goto_anchor  = &statement->gotos.next;
10243
10244         expect(';', end_error);
10245
10246         return statement;
10247 end_error:
10248         return create_invalid_statement();
10249 }
10250
10251 /**
10252  * Parse a continue statement.
10253  */
10254 static statement_t *parse_continue(void)
10255 {
10256         if (current_loop == NULL) {
10257                 errorf(HERE, "continue statement not within loop");
10258         }
10259
10260         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
10261
10262         eat(T_continue);
10263         expect(';', end_error);
10264
10265 end_error:
10266         return statement;
10267 }
10268
10269 /**
10270  * Parse a break statement.
10271  */
10272 static statement_t *parse_break(void)
10273 {
10274         if (current_switch == NULL && current_loop == NULL) {
10275                 errorf(HERE, "break statement not within loop or switch");
10276         }
10277
10278         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
10279
10280         eat(T_break);
10281         expect(';', end_error);
10282
10283 end_error:
10284         return statement;
10285 }
10286
10287 /**
10288  * Parse a __leave statement.
10289  */
10290 static statement_t *parse_leave_statement(void)
10291 {
10292         if (current_try == NULL) {
10293                 errorf(HERE, "__leave statement not within __try");
10294         }
10295
10296         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
10297
10298         eat(T___leave);
10299         expect(';', end_error);
10300
10301 end_error:
10302         return statement;
10303 }
10304
10305 /**
10306  * Check if a given entity represents a local variable.
10307  */
10308 static bool is_local_variable(const entity_t *entity)
10309 {
10310         if (entity->kind != ENTITY_VARIABLE)
10311                 return false;
10312
10313         switch ((storage_class_tag_t) entity->declaration.storage_class) {
10314         case STORAGE_CLASS_AUTO:
10315         case STORAGE_CLASS_REGISTER: {
10316                 const type_t *type = skip_typeref(entity->declaration.type);
10317                 if (is_type_function(type)) {
10318                         return false;
10319                 } else {
10320                         return true;
10321                 }
10322         }
10323         default:
10324                 return false;
10325         }
10326 }
10327
10328 /**
10329  * Check if a given expression represents a local variable.
10330  */
10331 static bool expression_is_local_variable(const expression_t *expression)
10332 {
10333         if (expression->base.kind != EXPR_REFERENCE) {
10334                 return false;
10335         }
10336         const entity_t *entity = expression->reference.entity;
10337         return is_local_variable(entity);
10338 }
10339
10340 /**
10341  * Check if a given expression represents a local variable and
10342  * return its declaration then, else return NULL.
10343  */
10344 entity_t *expression_is_variable(const expression_t *expression)
10345 {
10346         if (expression->base.kind != EXPR_REFERENCE) {
10347                 return NULL;
10348         }
10349         entity_t *entity = expression->reference.entity;
10350         if (entity->kind != ENTITY_VARIABLE)
10351                 return NULL;
10352
10353         return entity;
10354 }
10355
10356 /**
10357  * Parse a return statement.
10358  */
10359 static statement_t *parse_return(void)
10360 {
10361         eat(T_return);
10362
10363         statement_t *statement = allocate_statement_zero(STATEMENT_RETURN);
10364
10365         expression_t *return_value = NULL;
10366         if (token.type != ';') {
10367                 return_value = parse_expression();
10368                 mark_vars_read(return_value, NULL);
10369         }
10370
10371         const type_t *const func_type = skip_typeref(current_function->base.type);
10372         assert(is_type_function(func_type));
10373         type_t *const return_type = skip_typeref(func_type->function.return_type);
10374
10375         source_position_t const *const pos = &statement->base.source_position;
10376         if (return_value != NULL) {
10377                 type_t *return_value_type = skip_typeref(return_value->base.type);
10378
10379                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10380                         if (is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
10381                                 /* ISO/IEC 14882:1998(E) §6.6.3:2 */
10382                                 /* Only warn in C mode, because GCC does the same */
10383                                 if (c_mode & _CXX || strict_mode) {
10384                                         errorf(pos,
10385                                                         "'return' with a value, in function returning 'void'");
10386                                 } else if (warning.other) {
10387                                         warningf(pos,
10388                                                         "'return' with a value, in function returning 'void'");
10389                                 }
10390                         } else if (!(c_mode & _CXX)) { /* ISO/IEC 14882:1998(E) §6.6.3:3 */
10391                                 /* Only warn in C mode, because GCC does the same */
10392                                 if (strict_mode) {
10393                                         errorf(pos,
10394                                                         "'return' with expression in function return 'void'");
10395                                 } else if (warning.other) {
10396                                         warningf(pos,
10397                                                         "'return' with expression in function return 'void'");
10398                                 }
10399                         }
10400                 } else {
10401                         assign_error_t error = semantic_assign(return_type, return_value);
10402                         report_assign_error(error, return_type, return_value, "'return'",
10403                                         pos);
10404                 }
10405                 return_value = create_implicit_cast(return_value, return_type);
10406                 /* check for returning address of a local var */
10407                 if (warning.other && return_value != NULL
10408                                 && return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
10409                         const expression_t *expression = return_value->unary.value;
10410                         if (expression_is_local_variable(expression)) {
10411                                 warningf(pos, "function returns address of local variable");
10412                         }
10413                 }
10414         } else if (warning.other && !is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10415                 /* ISO/IEC 14882:1998(E) §6.6.3:3 */
10416                 if (c_mode & _CXX || strict_mode) {
10417                         errorf(pos,
10418                                         "'return' without value, in function returning non-void");
10419                 } else {
10420                         warningf(pos,
10421                                         "'return' without value, in function returning non-void");
10422                 }
10423         }
10424         statement->returns.value = return_value;
10425
10426         expect(';', end_error);
10427
10428 end_error:
10429         return statement;
10430 }
10431
10432 /**
10433  * Parse a declaration statement.
10434  */
10435 static statement_t *parse_declaration_statement(void)
10436 {
10437         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10438
10439         entity_t *before = current_scope->last_entity;
10440         if (GNU_MODE) {
10441                 parse_external_declaration();
10442         } else {
10443                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10444         }
10445
10446         if (before == NULL) {
10447                 statement->declaration.declarations_begin = current_scope->entities;
10448         } else {
10449                 statement->declaration.declarations_begin = before->base.next;
10450         }
10451         statement->declaration.declarations_end = current_scope->last_entity;
10452
10453         return statement;
10454 }
10455
10456 /**
10457  * Parse an expression statement, ie. expr ';'.
10458  */
10459 static statement_t *parse_expression_statement(void)
10460 {
10461         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10462
10463         expression_t *const expr         = parse_expression();
10464         statement->expression.expression = expr;
10465         mark_vars_read(expr, ENT_ANY);
10466
10467         expect(';', end_error);
10468
10469 end_error:
10470         return statement;
10471 }
10472
10473 /**
10474  * Parse a microsoft __try { } __finally { } or
10475  * __try{ } __except() { }
10476  */
10477 static statement_t *parse_ms_try_statment(void)
10478 {
10479         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
10480         eat(T___try);
10481
10482         PUSH_PARENT(statement);
10483
10484         ms_try_statement_t *rem = current_try;
10485         current_try = &statement->ms_try;
10486         statement->ms_try.try_statement = parse_compound_statement(false);
10487         current_try = rem;
10488
10489         POP_PARENT;
10490
10491         if (token.type == T___except) {
10492                 eat(T___except);
10493                 expect('(', end_error);
10494                 add_anchor_token(')');
10495                 expression_t *const expr = parse_expression();
10496                 mark_vars_read(expr, NULL);
10497                 type_t       *      type = skip_typeref(expr->base.type);
10498                 if (is_type_integer(type)) {
10499                         type = promote_integer(type);
10500                 } else if (is_type_valid(type)) {
10501                         errorf(&expr->base.source_position,
10502                                "__expect expression is not an integer, but '%T'", type);
10503                         type = type_error_type;
10504                 }
10505                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
10506                 rem_anchor_token(')');
10507                 expect(')', end_error);
10508                 statement->ms_try.final_statement = parse_compound_statement(false);
10509         } else if (token.type == T__finally) {
10510                 eat(T___finally);
10511                 statement->ms_try.final_statement = parse_compound_statement(false);
10512         } else {
10513                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
10514                 return create_invalid_statement();
10515         }
10516         return statement;
10517 end_error:
10518         return create_invalid_statement();
10519 }
10520
10521 static statement_t *parse_empty_statement(void)
10522 {
10523         if (warning.empty_statement) {
10524                 warningf(HERE, "statement is empty");
10525         }
10526         statement_t *const statement = create_empty_statement();
10527         eat(';');
10528         return statement;
10529 }
10530
10531 static statement_t *parse_local_label_declaration(void)
10532 {
10533         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10534
10535         eat(T___label__);
10536
10537         entity_t *begin = NULL, *end = NULL;
10538
10539         while (true) {
10540                 if (token.type != T_IDENTIFIER) {
10541                         parse_error_expected("while parsing local label declaration",
10542                                 T_IDENTIFIER, NULL);
10543                         goto end_error;
10544                 }
10545                 symbol_t *symbol = token.v.symbol;
10546                 entity_t *entity = get_entity(symbol, NAMESPACE_LABEL);
10547                 if (entity != NULL && entity->base.parent_scope == current_scope) {
10548                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition %P)",
10549                                symbol, &entity->base.source_position);
10550                 } else {
10551                         entity = allocate_entity_zero(ENTITY_LOCAL_LABEL);
10552
10553                         entity->base.parent_scope    = current_scope;
10554                         entity->base.namespc         = NAMESPACE_LABEL;
10555                         entity->base.source_position = token.source_position;
10556                         entity->base.symbol          = symbol;
10557
10558                         if (end != NULL)
10559                                 end->base.next = entity;
10560                         end = entity;
10561                         if (begin == NULL)
10562                                 begin = entity;
10563
10564                         environment_push(entity);
10565                 }
10566                 next_token();
10567
10568                 if (token.type != ',')
10569                         break;
10570                 next_token();
10571         }
10572         eat(';');
10573 end_error:
10574         statement->declaration.declarations_begin = begin;
10575         statement->declaration.declarations_end   = end;
10576         return statement;
10577 }
10578
10579 static void parse_namespace_definition(void)
10580 {
10581         eat(T_namespace);
10582
10583         entity_t *entity = NULL;
10584         symbol_t *symbol = NULL;
10585
10586         if (token.type == T_IDENTIFIER) {
10587                 symbol = token.v.symbol;
10588                 next_token();
10589
10590                 entity = get_entity(symbol, NAMESPACE_NORMAL);
10591                 if (entity != NULL && entity->kind != ENTITY_NAMESPACE
10592                                 && entity->base.parent_scope == current_scope) {
10593                         error_redefined_as_different_kind(&token.source_position,
10594                                                           entity, ENTITY_NAMESPACE);
10595                         entity = NULL;
10596                 }
10597         }
10598
10599         if (entity == NULL) {
10600                 entity                       = allocate_entity_zero(ENTITY_NAMESPACE);
10601                 entity->base.symbol          = symbol;
10602                 entity->base.source_position = token.source_position;
10603                 entity->base.namespc         = NAMESPACE_NORMAL;
10604                 entity->base.parent_scope    = current_scope;
10605         }
10606
10607         if (token.type == '=') {
10608                 /* TODO: parse namespace alias */
10609                 panic("namespace alias definition not supported yet");
10610         }
10611
10612         environment_push(entity);
10613         append_entity(current_scope, entity);
10614
10615         size_t const  top       = environment_top();
10616         scope_t      *old_scope = scope_push(&entity->namespacee.members);
10617
10618         expect('{', end_error);
10619         parse_externals();
10620         expect('}', end_error);
10621
10622 end_error:
10623         assert(current_scope == &entity->namespacee.members);
10624         scope_pop(old_scope);
10625         environment_pop_to(top);
10626 }
10627
10628 /**
10629  * Parse a statement.
10630  * There's also parse_statement() which additionally checks for
10631  * "statement has no effect" warnings
10632  */
10633 static statement_t *intern_parse_statement(void)
10634 {
10635         statement_t *statement = NULL;
10636
10637         /* declaration or statement */
10638         add_anchor_token(';');
10639         switch (token.type) {
10640         case T_IDENTIFIER: {
10641                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
10642                 if (la1_type == ':') {
10643                         statement = parse_label_statement();
10644                 } else if (is_typedef_symbol(token.v.symbol)) {
10645                         statement = parse_declaration_statement();
10646                 } else {
10647                         /* it's an identifier, the grammar says this must be an
10648                          * expression statement. However it is common that users mistype
10649                          * declaration types, so we guess a bit here to improve robustness
10650                          * for incorrect programs */
10651                         switch (la1_type) {
10652                         case '&':
10653                         case '*':
10654                                 if (get_entity(token.v.symbol, NAMESPACE_NORMAL) != NULL)
10655                                         goto expression_statment;
10656                                 /* FALLTHROUGH */
10657
10658                         DECLARATION_START
10659                         case T_IDENTIFIER:
10660                                 statement = parse_declaration_statement();
10661                                 break;
10662
10663                         default:
10664 expression_statment:
10665                                 statement = parse_expression_statement();
10666                                 break;
10667                         }
10668                 }
10669                 break;
10670         }
10671
10672         case T___extension__:
10673                 /* This can be a prefix to a declaration or an expression statement.
10674                  * We simply eat it now and parse the rest with tail recursion. */
10675                 do {
10676                         next_token();
10677                 } while (token.type == T___extension__);
10678                 bool old_gcc_extension = in_gcc_extension;
10679                 in_gcc_extension       = true;
10680                 statement = intern_parse_statement();
10681                 in_gcc_extension = old_gcc_extension;
10682                 break;
10683
10684         DECLARATION_START
10685                 statement = parse_declaration_statement();
10686                 break;
10687
10688         case T___label__:
10689                 statement = parse_local_label_declaration();
10690                 break;
10691
10692         case ';':         statement = parse_empty_statement();         break;
10693         case '{':         statement = parse_compound_statement(false); break;
10694         case T___leave:   statement = parse_leave_statement();         break;
10695         case T___try:     statement = parse_ms_try_statment();         break;
10696         case T_asm:       statement = parse_asm_statement();           break;
10697         case T_break:     statement = parse_break();                   break;
10698         case T_case:      statement = parse_case_statement();          break;
10699         case T_continue:  statement = parse_continue();                break;
10700         case T_default:   statement = parse_default_statement();       break;
10701         case T_do:        statement = parse_do();                      break;
10702         case T_for:       statement = parse_for();                     break;
10703         case T_goto:      statement = parse_goto();                    break;
10704         case T_if:        statement = parse_if();                      break;
10705         case T_return:    statement = parse_return();                  break;
10706         case T_switch:    statement = parse_switch();                  break;
10707         case T_while:     statement = parse_while();                   break;
10708
10709         EXPRESSION_START
10710                 statement = parse_expression_statement();
10711                 break;
10712
10713         default:
10714                 errorf(HERE, "unexpected token %K while parsing statement", &token);
10715                 statement = create_invalid_statement();
10716                 if (!at_anchor())
10717                         next_token();
10718                 break;
10719         }
10720         rem_anchor_token(';');
10721
10722         assert(statement != NULL
10723                         && statement->base.source_position.input_name != NULL);
10724
10725         return statement;
10726 }
10727
10728 /**
10729  * parse a statement and emits "statement has no effect" warning if needed
10730  * (This is really a wrapper around intern_parse_statement with check for 1
10731  *  single warning. It is needed, because for statement expressions we have
10732  *  to avoid the warning on the last statement)
10733  */
10734 static statement_t *parse_statement(void)
10735 {
10736         statement_t *statement = intern_parse_statement();
10737
10738         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
10739                 expression_t *expression = statement->expression.expression;
10740                 if (!expression_has_effect(expression)) {
10741                         warningf(&expression->base.source_position,
10742                                         "statement has no effect");
10743                 }
10744         }
10745
10746         return statement;
10747 }
10748
10749 /**
10750  * Parse a compound statement.
10751  */
10752 static statement_t *parse_compound_statement(bool inside_expression_statement)
10753 {
10754         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
10755
10756         PUSH_PARENT(statement);
10757
10758         eat('{');
10759         add_anchor_token('}');
10760         /* tokens, which can start a statement */
10761         /* TODO MS, __builtin_FOO */
10762         add_anchor_token('!');
10763         add_anchor_token('&');
10764         add_anchor_token('(');
10765         add_anchor_token('*');
10766         add_anchor_token('+');
10767         add_anchor_token('-');
10768         add_anchor_token('{');
10769         add_anchor_token('~');
10770         add_anchor_token(T_CHARACTER_CONSTANT);
10771         add_anchor_token(T_COLONCOLON);
10772         add_anchor_token(T_FLOATINGPOINT);
10773         add_anchor_token(T_IDENTIFIER);
10774         add_anchor_token(T_INTEGER);
10775         add_anchor_token(T_MINUSMINUS);
10776         add_anchor_token(T_PLUSPLUS);
10777         add_anchor_token(T_STRING_LITERAL);
10778         add_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10779         add_anchor_token(T_WIDE_STRING_LITERAL);
10780         add_anchor_token(T__Bool);
10781         add_anchor_token(T__Complex);
10782         add_anchor_token(T__Imaginary);
10783         add_anchor_token(T___FUNCTION__);
10784         add_anchor_token(T___PRETTY_FUNCTION__);
10785         add_anchor_token(T___alignof__);
10786         add_anchor_token(T___attribute__);
10787         add_anchor_token(T___builtin_va_start);
10788         add_anchor_token(T___extension__);
10789         add_anchor_token(T___func__);
10790         add_anchor_token(T___imag__);
10791         add_anchor_token(T___label__);
10792         add_anchor_token(T___real__);
10793         add_anchor_token(T___thread);
10794         add_anchor_token(T_asm);
10795         add_anchor_token(T_auto);
10796         add_anchor_token(T_bool);
10797         add_anchor_token(T_break);
10798         add_anchor_token(T_case);
10799         add_anchor_token(T_char);
10800         add_anchor_token(T_class);
10801         add_anchor_token(T_const);
10802         add_anchor_token(T_const_cast);
10803         add_anchor_token(T_continue);
10804         add_anchor_token(T_default);
10805         add_anchor_token(T_delete);
10806         add_anchor_token(T_double);
10807         add_anchor_token(T_do);
10808         add_anchor_token(T_dynamic_cast);
10809         add_anchor_token(T_enum);
10810         add_anchor_token(T_extern);
10811         add_anchor_token(T_false);
10812         add_anchor_token(T_float);
10813         add_anchor_token(T_for);
10814         add_anchor_token(T_goto);
10815         add_anchor_token(T_if);
10816         add_anchor_token(T_inline);
10817         add_anchor_token(T_int);
10818         add_anchor_token(T_long);
10819         add_anchor_token(T_new);
10820         add_anchor_token(T_operator);
10821         add_anchor_token(T_register);
10822         add_anchor_token(T_reinterpret_cast);
10823         add_anchor_token(T_restrict);
10824         add_anchor_token(T_return);
10825         add_anchor_token(T_short);
10826         add_anchor_token(T_signed);
10827         add_anchor_token(T_sizeof);
10828         add_anchor_token(T_static);
10829         add_anchor_token(T_static_cast);
10830         add_anchor_token(T_struct);
10831         add_anchor_token(T_switch);
10832         add_anchor_token(T_template);
10833         add_anchor_token(T_this);
10834         add_anchor_token(T_throw);
10835         add_anchor_token(T_true);
10836         add_anchor_token(T_try);
10837         add_anchor_token(T_typedef);
10838         add_anchor_token(T_typeid);
10839         add_anchor_token(T_typename);
10840         add_anchor_token(T_typeof);
10841         add_anchor_token(T_union);
10842         add_anchor_token(T_unsigned);
10843         add_anchor_token(T_using);
10844         add_anchor_token(T_void);
10845         add_anchor_token(T_volatile);
10846         add_anchor_token(T_wchar_t);
10847         add_anchor_token(T_while);
10848
10849         size_t const  top       = environment_top();
10850         scope_t      *old_scope = scope_push(&statement->compound.scope);
10851
10852         statement_t **anchor            = &statement->compound.statements;
10853         bool          only_decls_so_far = true;
10854         while (token.type != '}') {
10855                 if (token.type == T_EOF) {
10856                         errorf(&statement->base.source_position,
10857                                "EOF while parsing compound statement");
10858                         break;
10859                 }
10860                 statement_t *sub_statement = intern_parse_statement();
10861                 if (is_invalid_statement(sub_statement)) {
10862                         /* an error occurred. if we are at an anchor, return */
10863                         if (at_anchor())
10864                                 goto end_error;
10865                         continue;
10866                 }
10867
10868                 if (warning.declaration_after_statement) {
10869                         if (sub_statement->kind != STATEMENT_DECLARATION) {
10870                                 only_decls_so_far = false;
10871                         } else if (!only_decls_so_far) {
10872                                 warningf(&sub_statement->base.source_position,
10873                                          "ISO C90 forbids mixed declarations and code");
10874                         }
10875                 }
10876
10877                 *anchor = sub_statement;
10878
10879                 while (sub_statement->base.next != NULL)
10880                         sub_statement = sub_statement->base.next;
10881
10882                 anchor = &sub_statement->base.next;
10883         }
10884         next_token();
10885
10886         /* look over all statements again to produce no effect warnings */
10887         if (warning.unused_value) {
10888                 statement_t *sub_statement = statement->compound.statements;
10889                 for (; sub_statement != NULL; sub_statement = sub_statement->base.next) {
10890                         if (sub_statement->kind != STATEMENT_EXPRESSION)
10891                                 continue;
10892                         /* don't emit a warning for the last expression in an expression
10893                          * statement as it has always an effect */
10894                         if (inside_expression_statement && sub_statement->base.next == NULL)
10895                                 continue;
10896
10897                         expression_t *expression = sub_statement->expression.expression;
10898                         if (!expression_has_effect(expression)) {
10899                                 warningf(&expression->base.source_position,
10900                                          "statement has no effect");
10901                         }
10902                 }
10903         }
10904
10905 end_error:
10906         rem_anchor_token(T_while);
10907         rem_anchor_token(T_wchar_t);
10908         rem_anchor_token(T_volatile);
10909         rem_anchor_token(T_void);
10910         rem_anchor_token(T_using);
10911         rem_anchor_token(T_unsigned);
10912         rem_anchor_token(T_union);
10913         rem_anchor_token(T_typeof);
10914         rem_anchor_token(T_typename);
10915         rem_anchor_token(T_typeid);
10916         rem_anchor_token(T_typedef);
10917         rem_anchor_token(T_try);
10918         rem_anchor_token(T_true);
10919         rem_anchor_token(T_throw);
10920         rem_anchor_token(T_this);
10921         rem_anchor_token(T_template);
10922         rem_anchor_token(T_switch);
10923         rem_anchor_token(T_struct);
10924         rem_anchor_token(T_static_cast);
10925         rem_anchor_token(T_static);
10926         rem_anchor_token(T_sizeof);
10927         rem_anchor_token(T_signed);
10928         rem_anchor_token(T_short);
10929         rem_anchor_token(T_return);
10930         rem_anchor_token(T_restrict);
10931         rem_anchor_token(T_reinterpret_cast);
10932         rem_anchor_token(T_register);
10933         rem_anchor_token(T_operator);
10934         rem_anchor_token(T_new);
10935         rem_anchor_token(T_long);
10936         rem_anchor_token(T_int);
10937         rem_anchor_token(T_inline);
10938         rem_anchor_token(T_if);
10939         rem_anchor_token(T_goto);
10940         rem_anchor_token(T_for);
10941         rem_anchor_token(T_float);
10942         rem_anchor_token(T_false);
10943         rem_anchor_token(T_extern);
10944         rem_anchor_token(T_enum);
10945         rem_anchor_token(T_dynamic_cast);
10946         rem_anchor_token(T_do);
10947         rem_anchor_token(T_double);
10948         rem_anchor_token(T_delete);
10949         rem_anchor_token(T_default);
10950         rem_anchor_token(T_continue);
10951         rem_anchor_token(T_const_cast);
10952         rem_anchor_token(T_const);
10953         rem_anchor_token(T_class);
10954         rem_anchor_token(T_char);
10955         rem_anchor_token(T_case);
10956         rem_anchor_token(T_break);
10957         rem_anchor_token(T_bool);
10958         rem_anchor_token(T_auto);
10959         rem_anchor_token(T_asm);
10960         rem_anchor_token(T___thread);
10961         rem_anchor_token(T___real__);
10962         rem_anchor_token(T___label__);
10963         rem_anchor_token(T___imag__);
10964         rem_anchor_token(T___func__);
10965         rem_anchor_token(T___extension__);
10966         rem_anchor_token(T___builtin_va_start);
10967         rem_anchor_token(T___attribute__);
10968         rem_anchor_token(T___alignof__);
10969         rem_anchor_token(T___PRETTY_FUNCTION__);
10970         rem_anchor_token(T___FUNCTION__);
10971         rem_anchor_token(T__Imaginary);
10972         rem_anchor_token(T__Complex);
10973         rem_anchor_token(T__Bool);
10974         rem_anchor_token(T_WIDE_STRING_LITERAL);
10975         rem_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10976         rem_anchor_token(T_STRING_LITERAL);
10977         rem_anchor_token(T_PLUSPLUS);
10978         rem_anchor_token(T_MINUSMINUS);
10979         rem_anchor_token(T_INTEGER);
10980         rem_anchor_token(T_IDENTIFIER);
10981         rem_anchor_token(T_FLOATINGPOINT);
10982         rem_anchor_token(T_COLONCOLON);
10983         rem_anchor_token(T_CHARACTER_CONSTANT);
10984         rem_anchor_token('~');
10985         rem_anchor_token('{');
10986         rem_anchor_token('-');
10987         rem_anchor_token('+');
10988         rem_anchor_token('*');
10989         rem_anchor_token('(');
10990         rem_anchor_token('&');
10991         rem_anchor_token('!');
10992         rem_anchor_token('}');
10993         assert(current_scope == &statement->compound.scope);
10994         scope_pop(old_scope);
10995         environment_pop_to(top);
10996
10997         POP_PARENT;
10998         return statement;
10999 }
11000
11001 /**
11002  * Check for unused global static functions and variables
11003  */
11004 static void check_unused_globals(void)
11005 {
11006         if (!warning.unused_function && !warning.unused_variable)
11007                 return;
11008
11009         for (const entity_t *entity = file_scope->entities; entity != NULL;
11010              entity = entity->base.next) {
11011                 if (!is_declaration(entity))
11012                         continue;
11013
11014                 const declaration_t *declaration = &entity->declaration;
11015                 if (declaration->used                  ||
11016                     declaration->modifiers & DM_UNUSED ||
11017                     declaration->modifiers & DM_USED   ||
11018                     declaration->storage_class != STORAGE_CLASS_STATIC)
11019                         continue;
11020
11021                 type_t *const type = declaration->type;
11022                 const char *s;
11023                 if (entity->kind == ENTITY_FUNCTION) {
11024                         /* inhibit warning for static inline functions */
11025                         if (entity->function.is_inline)
11026                                 continue;
11027
11028                         s = entity->function.statement != NULL ? "defined" : "declared";
11029                 } else {
11030                         s = "defined";
11031                 }
11032
11033                 warningf(&declaration->base.source_position, "'%#T' %s but not used",
11034                         type, declaration->base.symbol, s);
11035         }
11036 }
11037
11038 static void parse_global_asm(void)
11039 {
11040         statement_t *statement = allocate_statement_zero(STATEMENT_ASM);
11041
11042         eat(T_asm);
11043         expect('(', end_error);
11044
11045         statement->asms.asm_text = parse_string_literals();
11046         statement->base.next     = unit->global_asm;
11047         unit->global_asm         = statement;
11048
11049         expect(')', end_error);
11050         expect(';', end_error);
11051
11052 end_error:;
11053 }
11054
11055 static void parse_linkage_specification(void)
11056 {
11057         eat(T_extern);
11058         assert(token.type == T_STRING_LITERAL);
11059
11060         const char *linkage = parse_string_literals().begin;
11061
11062         linkage_kind_t old_linkage = current_linkage;
11063         linkage_kind_t new_linkage;
11064         if (strcmp(linkage, "C") == 0) {
11065                 new_linkage = LINKAGE_C;
11066         } else if (strcmp(linkage, "C++") == 0) {
11067                 new_linkage = LINKAGE_CXX;
11068         } else {
11069                 errorf(HERE, "linkage string \"%s\" not recognized", linkage);
11070                 new_linkage = LINKAGE_INVALID;
11071         }
11072         current_linkage = new_linkage;
11073
11074         if (token.type == '{') {
11075                 next_token();
11076                 parse_externals();
11077                 expect('}', end_error);
11078         } else {
11079                 parse_external();
11080         }
11081
11082 end_error:
11083         assert(current_linkage == new_linkage);
11084         current_linkage = old_linkage;
11085 }
11086
11087 static void parse_external(void)
11088 {
11089         switch (token.type) {
11090                 DECLARATION_START_NO_EXTERN
11091                 case T_IDENTIFIER:
11092                 case T___extension__:
11093                 /* tokens below are for implicit int */
11094                 case '&': /* & x; -> int& x; (and error later, because C++ has no
11095                              implicit int) */
11096                 case '*': /* * x; -> int* x; */
11097                 case '(': /* (x); -> int (x); */
11098                         parse_external_declaration();
11099                         return;
11100
11101                 case T_extern:
11102                         if (look_ahead(1)->type == T_STRING_LITERAL) {
11103                                 parse_linkage_specification();
11104                         } else {
11105                                 parse_external_declaration();
11106                         }
11107                         return;
11108
11109                 case T_asm:
11110                         parse_global_asm();
11111                         return;
11112
11113                 case T_namespace:
11114                         parse_namespace_definition();
11115                         return;
11116
11117                 case ';':
11118                         if (!strict_mode) {
11119                                 if (warning.other)
11120                                         warningf(HERE, "stray ';' outside of function");
11121                                 next_token();
11122                                 return;
11123                         }
11124                         /* FALLTHROUGH */
11125
11126                 default:
11127                         errorf(HERE, "stray %K outside of function", &token);
11128                         if (token.type == '(' || token.type == '{' || token.type == '[')
11129                                 eat_until_matching_token(token.type);
11130                         next_token();
11131                         return;
11132         }
11133 }
11134
11135 static void parse_externals(void)
11136 {
11137         add_anchor_token('}');
11138         add_anchor_token(T_EOF);
11139
11140 #ifndef NDEBUG
11141         unsigned char token_anchor_copy[T_LAST_TOKEN];
11142         memcpy(token_anchor_copy, token_anchor_set, sizeof(token_anchor_copy));
11143 #endif
11144
11145         while (token.type != T_EOF && token.type != '}') {
11146 #ifndef NDEBUG
11147                 bool anchor_leak = false;
11148                 for (int i = 0; i != T_LAST_TOKEN; ++i) {
11149                         unsigned char count = token_anchor_set[i] - token_anchor_copy[i];
11150                         if (count != 0) {
11151                                 errorf(HERE, "Leaked anchor token %k %d times", i, count);
11152                                 anchor_leak = true;
11153                         }
11154                 }
11155                 if (in_gcc_extension) {
11156                         errorf(HERE, "Leaked __extension__");
11157                         anchor_leak = true;
11158                 }
11159
11160                 if (anchor_leak)
11161                         abort();
11162 #endif
11163
11164                 parse_external();
11165         }
11166
11167         rem_anchor_token(T_EOF);
11168         rem_anchor_token('}');
11169 }
11170
11171 /**
11172  * Parse a translation unit.
11173  */
11174 static void parse_translation_unit(void)
11175 {
11176         add_anchor_token(T_EOF);
11177
11178         while (true) {
11179                 parse_externals();
11180
11181                 if (token.type == T_EOF)
11182                         break;
11183
11184                 errorf(HERE, "stray %K outside of function", &token);
11185                 if (token.type == '(' || token.type == '{' || token.type == '[')
11186                         eat_until_matching_token(token.type);
11187                 next_token();
11188         }
11189 }
11190
11191 /**
11192  * Parse the input.
11193  *
11194  * @return  the translation unit or NULL if errors occurred.
11195  */
11196 void start_parsing(void)
11197 {
11198         environment_stack = NEW_ARR_F(stack_entry_t, 0);
11199         label_stack       = NEW_ARR_F(stack_entry_t, 0);
11200         diagnostic_count  = 0;
11201         error_count       = 0;
11202         warning_count     = 0;
11203
11204         type_set_output(stderr);
11205         ast_set_output(stderr);
11206
11207         assert(unit == NULL);
11208         unit = allocate_ast_zero(sizeof(unit[0]));
11209
11210         assert(file_scope == NULL);
11211         file_scope = &unit->scope;
11212
11213         assert(current_scope == NULL);
11214         scope_push(&unit->scope);
11215 }
11216
11217 translation_unit_t *finish_parsing(void)
11218 {
11219         assert(current_scope == &unit->scope);
11220         scope_pop(NULL);
11221
11222         assert(file_scope == &unit->scope);
11223         check_unused_globals();
11224         file_scope = NULL;
11225
11226         DEL_ARR_F(environment_stack);
11227         DEL_ARR_F(label_stack);
11228
11229         translation_unit_t *result = unit;
11230         unit = NULL;
11231         return result;
11232 }
11233
11234 /* GCC allows global arrays without size and assigns them a length of one,
11235  * if no different declaration follows */
11236 static void complete_incomplete_arrays(void)
11237 {
11238         size_t n = ARR_LEN(incomplete_arrays);
11239         for (size_t i = 0; i != n; ++i) {
11240                 declaration_t *const decl      = incomplete_arrays[i];
11241                 type_t        *const orig_type = decl->type;
11242                 type_t        *const type      = skip_typeref(orig_type);
11243
11244                 if (!is_type_incomplete(type))
11245                         continue;
11246
11247                 if (warning.other) {
11248                         warningf(&decl->base.source_position,
11249                                         "array '%#T' assumed to have one element",
11250                                         orig_type, decl->base.symbol);
11251                 }
11252
11253                 type_t *const new_type = duplicate_type(type);
11254                 new_type->array.size_constant     = true;
11255                 new_type->array.has_implicit_size = true;
11256                 new_type->array.size              = 1;
11257
11258                 type_t *const result = typehash_insert(new_type);
11259                 if (type != result)
11260                         free_type(type);
11261
11262                 decl->type = result;
11263         }
11264 }
11265
11266 void parse(void)
11267 {
11268         lookahead_bufpos = 0;
11269         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
11270                 next_token();
11271         }
11272         current_linkage   = c_mode & _CXX ? LINKAGE_CXX : LINKAGE_C;
11273         incomplete_arrays = NEW_ARR_F(declaration_t*, 0);
11274         parse_translation_unit();
11275         complete_incomplete_arrays();
11276         DEL_ARR_F(incomplete_arrays);
11277         incomplete_arrays = NULL;
11278 }
11279
11280 /**
11281  * Initialize the parser.
11282  */
11283 void init_parser(void)
11284 {
11285         sym_anonymous = symbol_table_insert("<anonymous>");
11286
11287         if (c_mode & _MS) {
11288                 /* add predefined symbols for extended-decl-modifier */
11289                 sym_align      = symbol_table_insert("align");
11290                 sym_allocate   = symbol_table_insert("allocate");
11291                 sym_dllimport  = symbol_table_insert("dllimport");
11292                 sym_dllexport  = symbol_table_insert("dllexport");
11293                 sym_naked      = symbol_table_insert("naked");
11294                 sym_noinline   = symbol_table_insert("noinline");
11295                 sym_noreturn   = symbol_table_insert("noreturn");
11296                 sym_nothrow    = symbol_table_insert("nothrow");
11297                 sym_novtable   = symbol_table_insert("novtable");
11298                 sym_property   = symbol_table_insert("property");
11299                 sym_get        = symbol_table_insert("get");
11300                 sym_put        = symbol_table_insert("put");
11301                 sym_selectany  = symbol_table_insert("selectany");
11302                 sym_thread     = symbol_table_insert("thread");
11303                 sym_uuid       = symbol_table_insert("uuid");
11304                 sym_deprecated = symbol_table_insert("deprecated");
11305                 sym_restrict   = symbol_table_insert("restrict");
11306                 sym_noalias    = symbol_table_insert("noalias");
11307         }
11308         memset(token_anchor_set, 0, sizeof(token_anchor_set));
11309
11310         init_expression_parsers();
11311         obstack_init(&temp_obst);
11312
11313         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
11314         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
11315 }
11316
11317 /**
11318  * Terminate the parser.
11319  */
11320 void exit_parser(void)
11321 {
11322         obstack_free(&temp_obst, NULL);
11323 }