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                         parse_identifier_list(scope);
4137                         goto parameters_finished;
4138                 }
4139         }
4140
4141         if (token.type == ')') {
4142                 /* ISO/IEC 14882:1998(E) §C.1.6:1 */
4143                 if (!(c_mode & _CXX))
4144                         type->unspecified_parameters = true;
4145                 goto parameters_finished;
4146         }
4147
4148         function_parameter_t *parameter;
4149         function_parameter_t *last_parameter = NULL;
4150
4151         while (true) {
4152                 switch (token.type) {
4153                 case T_DOTDOTDOT:
4154                         next_token();
4155                         type->variadic = true;
4156                         goto parameters_finished;
4157
4158                 case T_IDENTIFIER:
4159                 case T___extension__:
4160                 DECLARATION_START
4161                 {
4162                         entity_t *entity = parse_parameter();
4163                         if (entity->kind == ENTITY_TYPEDEF) {
4164                                 errorf(&entity->base.source_position,
4165                                        "typedef not allowed as function parameter");
4166                                 break;
4167                         }
4168                         assert(is_declaration(entity));
4169
4170                         /* func(void) is not a parameter */
4171                         if (last_parameter == NULL
4172                                         && token.type == ')'
4173                                         && entity->base.symbol == NULL
4174                                         && skip_typeref(entity->declaration.type) == type_void) {
4175                                 goto parameters_finished;
4176                         }
4177                         semantic_parameter_incomplete(entity);
4178
4179                         parameter = obstack_alloc(type_obst, sizeof(parameter[0]));
4180                         memset(parameter, 0, sizeof(parameter[0]));
4181                         parameter->type = entity->declaration.type;
4182
4183                         if (scope != NULL) {
4184                                 append_entity(scope, entity);
4185                         }
4186
4187                         if (last_parameter != NULL) {
4188                                 last_parameter->next = parameter;
4189                         } else {
4190                                 type->parameters = parameter;
4191                         }
4192                         last_parameter   = parameter;
4193                         break;
4194                 }
4195
4196                 default:
4197                         goto parameters_finished;
4198                 }
4199                 if (token.type != ',') {
4200                         goto parameters_finished;
4201                 }
4202                 next_token();
4203         }
4204
4205
4206 parameters_finished:
4207         rem_anchor_token(')');
4208         expect(')', end_error);
4209
4210 end_error:
4211         restore_anchor_state(',', saved_comma_state);
4212 }
4213
4214 typedef enum construct_type_kind_t {
4215         CONSTRUCT_INVALID,
4216         CONSTRUCT_POINTER,
4217         CONSTRUCT_REFERENCE,
4218         CONSTRUCT_FUNCTION,
4219         CONSTRUCT_ARRAY
4220 } construct_type_kind_t;
4221
4222 typedef struct construct_type_t construct_type_t;
4223 struct construct_type_t {
4224         construct_type_kind_t  kind;
4225         construct_type_t      *next;
4226 };
4227
4228 typedef struct parsed_pointer_t parsed_pointer_t;
4229 struct parsed_pointer_t {
4230         construct_type_t  construct_type;
4231         type_qualifiers_t type_qualifiers;
4232         variable_t        *base_variable;  /**< MS __based extension. */
4233 };
4234
4235 typedef struct parsed_reference_t parsed_reference_t;
4236 struct parsed_reference_t {
4237         construct_type_t construct_type;
4238 };
4239
4240 typedef struct construct_function_type_t construct_function_type_t;
4241 struct construct_function_type_t {
4242         construct_type_t  construct_type;
4243         type_t           *function_type;
4244 };
4245
4246 typedef struct parsed_array_t parsed_array_t;
4247 struct parsed_array_t {
4248         construct_type_t  construct_type;
4249         type_qualifiers_t type_qualifiers;
4250         bool              is_static;
4251         bool              is_variable;
4252         expression_t     *size;
4253 };
4254
4255 typedef struct construct_base_type_t construct_base_type_t;
4256 struct construct_base_type_t {
4257         construct_type_t  construct_type;
4258         type_t           *type;
4259 };
4260
4261 static construct_type_t *parse_pointer_declarator(variable_t *base_variable)
4262 {
4263         eat('*');
4264
4265         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
4266         memset(pointer, 0, sizeof(pointer[0]));
4267         pointer->construct_type.kind = CONSTRUCT_POINTER;
4268         pointer->type_qualifiers     = parse_type_qualifiers();
4269         pointer->base_variable       = base_variable;
4270
4271         return &pointer->construct_type;
4272 }
4273
4274 static construct_type_t *parse_reference_declarator(void)
4275 {
4276         eat('&');
4277
4278         parsed_reference_t *reference = obstack_alloc(&temp_obst, sizeof(reference[0]));
4279         memset(reference, 0, sizeof(reference[0]));
4280         reference->construct_type.kind = CONSTRUCT_REFERENCE;
4281
4282         return (construct_type_t*)reference;
4283 }
4284
4285 static construct_type_t *parse_array_declarator(void)
4286 {
4287         eat('[');
4288         add_anchor_token(']');
4289
4290         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
4291         memset(array, 0, sizeof(array[0]));
4292         array->construct_type.kind = CONSTRUCT_ARRAY;
4293
4294         if (token.type == T_static) {
4295                 array->is_static = true;
4296                 next_token();
4297         }
4298
4299         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
4300         if (type_qualifiers != 0) {
4301                 if (token.type == T_static) {
4302                         array->is_static = true;
4303                         next_token();
4304                 }
4305         }
4306         array->type_qualifiers = type_qualifiers;
4307
4308         if (token.type == '*' && look_ahead(1)->type == ']') {
4309                 array->is_variable = true;
4310                 next_token();
4311         } else if (token.type != ']') {
4312                 array->size = parse_assignment_expression();
4313         }
4314
4315         rem_anchor_token(']');
4316         expect(']', end_error);
4317
4318 end_error:
4319         return &array->construct_type;
4320 }
4321
4322 static construct_type_t *parse_function_declarator(scope_t *scope,
4323                                                    decl_modifiers_t modifiers)
4324 {
4325         type_t          *type  = allocate_type_zero(TYPE_FUNCTION);
4326         function_type_t *ftype = &type->function;
4327
4328         ftype->linkage = current_linkage;
4329
4330         switch (modifiers & (DM_CDECL | DM_STDCALL | DM_FASTCALL | DM_THISCALL)) {
4331                 case DM_NONE:     break;
4332                 case DM_CDECL:    ftype->calling_convention = CC_CDECL;    break;
4333                 case DM_STDCALL:  ftype->calling_convention = CC_STDCALL;  break;
4334                 case DM_FASTCALL: ftype->calling_convention = CC_FASTCALL; break;
4335                 case DM_THISCALL: ftype->calling_convention = CC_THISCALL; break;
4336
4337                 default:
4338                         errorf(HERE, "multiple calling conventions in declaration");
4339                         break;
4340         }
4341
4342         parse_parameters(ftype, scope);
4343
4344         construct_function_type_t *construct_function_type =
4345                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
4346         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
4347         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
4348         construct_function_type->function_type       = type;
4349
4350         return &construct_function_type->construct_type;
4351 }
4352
4353 typedef struct parse_declarator_env_t {
4354         decl_modifiers_t   modifiers;
4355         symbol_t          *symbol;
4356         source_position_t  source_position;
4357         scope_t            parameters;
4358 } parse_declarator_env_t;
4359
4360 static construct_type_t *parse_inner_declarator(parse_declarator_env_t *env,
4361                 bool may_be_abstract)
4362 {
4363         /* construct a single linked list of construct_type_t's which describe
4364          * how to construct the final declarator type */
4365         construct_type_t *first      = NULL;
4366         construct_type_t *last       = NULL;
4367         gnu_attribute_t  *attributes = NULL;
4368
4369         decl_modifiers_t modifiers = parse_attributes(&attributes);
4370
4371         /* MS __based extension */
4372         based_spec_t base_spec;
4373         base_spec.base_variable = NULL;
4374
4375         for (;;) {
4376                 construct_type_t *type;
4377                 switch (token.type) {
4378                         case '&':
4379                                 if (!(c_mode & _CXX))
4380                                         errorf(HERE, "references are only available for C++");
4381                                 if (base_spec.base_variable != NULL && warning.other) {
4382                                         warningf(&base_spec.source_position,
4383                                                  "__based does not precede a pointer operator, ignored");
4384                                 }
4385                                 type = parse_reference_declarator();
4386                                 /* consumed */
4387                                 base_spec.base_variable = NULL;
4388                                 break;
4389
4390                         case '*':
4391                                 type = parse_pointer_declarator(base_spec.base_variable);
4392                                 /* consumed */
4393                                 base_spec.base_variable = NULL;
4394                                 break;
4395
4396                         case T__based:
4397                                 next_token();
4398                                 expect('(', end_error);
4399                                 add_anchor_token(')');
4400                                 parse_microsoft_based(&base_spec);
4401                                 rem_anchor_token(')');
4402                                 expect(')', end_error);
4403                                 continue;
4404
4405                         default:
4406                                 goto ptr_operator_end;
4407                 }
4408
4409                 if (last == NULL) {
4410                         first = type;
4411                         last  = type;
4412                 } else {
4413                         last->next = type;
4414                         last       = type;
4415                 }
4416
4417                 /* TODO: find out if this is correct */
4418                 modifiers |= parse_attributes(&attributes);
4419         }
4420 ptr_operator_end:
4421         if (base_spec.base_variable != NULL && warning.other) {
4422                 warningf(&base_spec.source_position,
4423                          "__based does not precede a pointer operator, ignored");
4424         }
4425
4426         if (env != NULL) {
4427                 modifiers      |= env->modifiers;
4428                 env->modifiers  = modifiers;
4429         }
4430
4431         construct_type_t *inner_types = NULL;
4432
4433         switch (token.type) {
4434         case T_IDENTIFIER:
4435                 if (env == NULL) {
4436                         errorf(HERE, "no identifier expected in typename");
4437                 } else {
4438                         env->symbol          = token.v.symbol;
4439                         env->source_position = token.source_position;
4440                 }
4441                 next_token();
4442                 break;
4443         case '(':
4444                 /* §6.7.6:2 footnote 126:  Empty parentheses in a type name are
4445                  * interpreted as ``function with no parameter specification'', rather
4446                  * than redundant parentheses around the omitted identifier. */
4447                 if (look_ahead(1)->type != ')') {
4448                         next_token();
4449                         add_anchor_token(')');
4450                         inner_types = parse_inner_declarator(env, may_be_abstract);
4451                         if (inner_types != NULL) {
4452                                 /* All later declarators only modify the return type */
4453                                 env = NULL;
4454                         }
4455                         rem_anchor_token(')');
4456                         expect(')', end_error);
4457                 }
4458                 break;
4459         default:
4460                 if (may_be_abstract)
4461                         break;
4462                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
4463                 eat_until_anchor();
4464                 return NULL;
4465         }
4466
4467         construct_type_t *p = last;
4468
4469         while (true) {
4470                 construct_type_t *type;
4471                 switch (token.type) {
4472                 case '(': {
4473                         scope_t *scope = NULL;
4474                         if (env != NULL)
4475                                 scope = &env->parameters;
4476
4477                         type = parse_function_declarator(scope, modifiers);
4478                         break;
4479                 }
4480                 case '[':
4481                         type = parse_array_declarator();
4482                         break;
4483                 default:
4484                         goto declarator_finished;
4485                 }
4486
4487                 /* insert in the middle of the list (behind p) */
4488                 if (p != NULL) {
4489                         type->next = p->next;
4490                         p->next    = type;
4491                 } else {
4492                         type->next = first;
4493                         first      = type;
4494                 }
4495                 if (last == p) {
4496                         last = type;
4497                 }
4498         }
4499
4500 declarator_finished:
4501         /* append inner_types at the end of the list, we don't to set last anymore
4502          * as it's not needed anymore */
4503         if (last == NULL) {
4504                 assert(first == NULL);
4505                 first = inner_types;
4506         } else {
4507                 last->next = inner_types;
4508         }
4509
4510         return first;
4511 end_error:
4512         return NULL;
4513 }
4514
4515 static void parse_declaration_attributes(entity_t *entity)
4516 {
4517         gnu_attribute_t  *attributes = NULL;
4518         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
4519
4520         if (entity == NULL)
4521                 return;
4522
4523         type_t *type;
4524         if (entity->kind == ENTITY_TYPEDEF) {
4525                 modifiers |= entity->typedefe.modifiers;
4526                 type       = entity->typedefe.type;
4527         } else {
4528                 assert(is_declaration(entity));
4529                 modifiers |= entity->declaration.modifiers;
4530                 type       = entity->declaration.type;
4531         }
4532         if (type == NULL)
4533                 return;
4534
4535         /* handle these strange/stupid mode attributes */
4536         gnu_attribute_t *attribute = attributes;
4537         for ( ; attribute != NULL; attribute = attribute->next) {
4538                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
4539                         continue;
4540
4541                 atomic_type_kind_t  akind = attribute->u.akind;
4542                 if (!is_type_signed(type)) {
4543                         switch (akind) {
4544                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
4545                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
4546                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
4547                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
4548                         default:
4549                                 panic("invalid akind in mode attribute");
4550                         }
4551                 } else {
4552                         switch (akind) {
4553                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_SCHAR; break;
4554                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_SHORT; break;
4555                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_INT; break;
4556                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_LONGLONG; break;
4557                         default:
4558                                 panic("invalid akind in mode attribute");
4559                         }
4560                 }
4561
4562                 type = make_atomic_type(akind, type->base.qualifiers);
4563         }
4564
4565         type_modifiers_t type_modifiers = type->base.modifiers;
4566         if (modifiers & DM_TRANSPARENT_UNION)
4567                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
4568
4569         if (type->base.modifiers != type_modifiers) {
4570                 type_t *copy = duplicate_type(type);
4571                 copy->base.modifiers = type_modifiers;
4572
4573                 type = typehash_insert(copy);
4574                 if (type != copy) {
4575                         obstack_free(type_obst, copy);
4576                 }
4577         }
4578
4579         if (entity->kind == ENTITY_TYPEDEF) {
4580                 entity->typedefe.type      = type;
4581                 entity->typedefe.modifiers = modifiers;
4582         } else {
4583                 entity->declaration.type      = type;
4584                 entity->declaration.modifiers = modifiers;
4585         }
4586 }
4587
4588 static type_t *construct_declarator_type(construct_type_t *construct_list, type_t *type)
4589 {
4590         construct_type_t *iter = construct_list;
4591         for (; iter != NULL; iter = iter->next) {
4592                 switch (iter->kind) {
4593                 case CONSTRUCT_INVALID:
4594                         internal_errorf(HERE, "invalid type construction found");
4595                 case CONSTRUCT_FUNCTION: {
4596                         construct_function_type_t *construct_function_type
4597                                 = (construct_function_type_t*) iter;
4598
4599                         type_t *function_type = construct_function_type->function_type;
4600
4601                         function_type->function.return_type = type;
4602
4603                         type_t *skipped_return_type = skip_typeref(type);
4604                         /* §6.7.5.3(1) */
4605                         if (is_type_function(skipped_return_type)) {
4606                                 errorf(HERE, "function returning function is not allowed");
4607                         } else if (is_type_array(skipped_return_type)) {
4608                                 errorf(HERE, "function returning array is not allowed");
4609                         } else {
4610                                 if (skipped_return_type->base.qualifiers != 0 && warning.other) {
4611                                         warningf(HERE,
4612                                                 "type qualifiers in return type of function type are meaningless");
4613                                 }
4614                         }
4615
4616                         type = function_type;
4617                         break;
4618                 }
4619
4620                 case CONSTRUCT_POINTER: {
4621                         if (is_type_reference(skip_typeref(type)))
4622                                 errorf(HERE, "cannot declare a pointer to reference");
4623
4624                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
4625                         type = make_based_pointer_type(type, parsed_pointer->type_qualifiers, parsed_pointer->base_variable);
4626                         continue;
4627                 }
4628
4629                 case CONSTRUCT_REFERENCE:
4630                         if (is_type_reference(skip_typeref(type)))
4631                                 errorf(HERE, "cannot declare a reference to reference");
4632
4633                         type = make_reference_type(type);
4634                         continue;
4635
4636                 case CONSTRUCT_ARRAY: {
4637                         if (is_type_reference(skip_typeref(type)))
4638                                 errorf(HERE, "cannot declare an array of references");
4639
4640                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
4641                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY);
4642
4643                         expression_t *size_expression = parsed_array->size;
4644                         if (size_expression != NULL) {
4645                                 size_expression
4646                                         = create_implicit_cast(size_expression, type_size_t);
4647                         }
4648
4649                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
4650                         array_type->array.element_type    = type;
4651                         array_type->array.is_static       = parsed_array->is_static;
4652                         array_type->array.is_variable     = parsed_array->is_variable;
4653                         array_type->array.size_expression = size_expression;
4654
4655                         if (size_expression != NULL) {
4656                                 if (is_constant_expression(size_expression)) {
4657                                         array_type->array.size_constant = true;
4658                                         array_type->array.size
4659                                                 = fold_constant(size_expression);
4660                                 } else {
4661                                         array_type->array.is_vla = true;
4662                                 }
4663                         }
4664
4665                         type_t *skipped_type = skip_typeref(type);
4666                         /* §6.7.5.2(1) */
4667                         if (is_type_incomplete(skipped_type)) {
4668                                 errorf(HERE, "array of incomplete type '%T' is not allowed", type);
4669                         } else if (is_type_function(skipped_type)) {
4670                                 errorf(HERE, "array of functions is not allowed");
4671                         }
4672                         type = array_type;
4673                         break;
4674                 }
4675                 }
4676
4677                 type_t *hashed_type = typehash_insert(type);
4678                 if (hashed_type != type) {
4679                         /* the function type was constructed earlier freeing it here will
4680                          * destroy other types... */
4681                         if (iter->kind != CONSTRUCT_FUNCTION) {
4682                                 free_type(type);
4683                         }
4684                         type = hashed_type;
4685                 }
4686         }
4687
4688         return type;
4689 }
4690
4691 static type_t *automatic_type_conversion(type_t *orig_type);
4692
4693 static type_t *semantic_parameter(const source_position_t *pos,
4694                                   type_t *type,
4695                                   const declaration_specifiers_t *specifiers,
4696                                   symbol_t *symbol)
4697 {
4698         /* §6.7.5.3:7  A declaration of a parameter as ``array of type''
4699          *             shall be adjusted to ``qualified pointer to type'',
4700          *             [...]
4701          * §6.7.5.3:8  A declaration of a parameter as ``function returning
4702          *             type'' shall be adjusted to ``pointer to function
4703          *             returning type'', as in 6.3.2.1. */
4704         type = automatic_type_conversion(type);
4705
4706         if (specifiers->is_inline && is_type_valid(type)) {
4707                 errorf(pos, "parameter '%Y' declared 'inline'", symbol);
4708         }
4709
4710         /* §6.9.1:6  The declarations in the declaration list shall contain
4711          *           no storage-class specifier other than register and no
4712          *           initializations. */
4713         if (specifiers->thread_local || (
4714                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4715                         specifiers->storage_class != STORAGE_CLASS_REGISTER)
4716            ) {
4717                 errorf(pos, "invalid storage class for parameter '%Y'", symbol);
4718         }
4719
4720         /* delay test for incomplete type, because we might have (void)
4721          * which is legal but incomplete... */
4722
4723         return type;
4724 }
4725
4726 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
4727                                   declarator_flags_t flags)
4728 {
4729         parse_declarator_env_t env;
4730         memset(&env, 0, sizeof(env));
4731         env.modifiers = specifiers->modifiers;
4732
4733         construct_type_t *construct_type =
4734                 parse_inner_declarator(&env, (flags & DECL_MAY_BE_ABSTRACT) != 0);
4735         type_t           *orig_type      =
4736                 construct_declarator_type(construct_type, specifiers->type);
4737         type_t           *type           = skip_typeref(orig_type);
4738
4739         if (construct_type != NULL) {
4740                 obstack_free(&temp_obst, construct_type);
4741         }
4742
4743         entity_t *entity;
4744         if (specifiers->storage_class == STORAGE_CLASS_TYPEDEF) {
4745                 entity                       = allocate_entity_zero(ENTITY_TYPEDEF);
4746                 entity->base.symbol          = env.symbol;
4747                 entity->base.source_position = env.source_position;
4748                 entity->typedefe.type        = orig_type;
4749
4750                 if (anonymous_entity != NULL) {
4751                         if (is_type_compound(type)) {
4752                                 assert(anonymous_entity->compound.alias == NULL);
4753                                 assert(anonymous_entity->kind == ENTITY_STRUCT ||
4754                                        anonymous_entity->kind == ENTITY_UNION);
4755                                 anonymous_entity->compound.alias = entity;
4756                                 anonymous_entity = NULL;
4757                         } else if (is_type_enum(type)) {
4758                                 assert(anonymous_entity->enume.alias == NULL);
4759                                 assert(anonymous_entity->kind == ENTITY_ENUM);
4760                                 anonymous_entity->enume.alias = entity;
4761                                 anonymous_entity = NULL;
4762                         }
4763                 }
4764         } else {
4765                 /* create a declaration type entity */
4766                 if (flags & DECL_CREATE_COMPOUND_MEMBER) {
4767                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
4768
4769                         if (specifiers->is_inline && is_type_valid(type)) {
4770                                 errorf(&env.source_position,
4771                                                 "compound member '%Y' declared 'inline'", env.symbol);
4772                         }
4773
4774                         if (specifiers->thread_local ||
4775                                 specifiers->storage_class != STORAGE_CLASS_NONE) {
4776                                 errorf(&env.source_position,
4777                                            "compound member '%Y' must have no storage class",
4778                                            env.symbol);
4779                         }
4780                 } else if (flags & DECL_IS_PARAMETER) {
4781                         orig_type = semantic_parameter(&env.source_position, orig_type,
4782                                                        specifiers, env.symbol);
4783
4784                         entity = allocate_entity_zero(ENTITY_PARAMETER);
4785                 } else if (is_type_function(type)) {
4786                         entity = allocate_entity_zero(ENTITY_FUNCTION);
4787
4788                         entity->function.is_inline  = specifiers->is_inline;
4789                         entity->function.parameters = env.parameters;
4790
4791                         if (specifiers->thread_local || (
4792                                         specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4793                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
4794                                         specifiers->storage_class != STORAGE_CLASS_STATIC)
4795                            ) {
4796                                 errorf(&env.source_position,
4797                                            "invalid storage class for function '%Y'", env.symbol);
4798                         }
4799                 } else {
4800                         entity = allocate_entity_zero(ENTITY_VARIABLE);
4801
4802                         entity->variable.get_property_sym = specifiers->get_property_sym;
4803                         entity->variable.put_property_sym = specifiers->put_property_sym;
4804                         if (specifiers->alignment != 0) {
4805                                 /* TODO: add checks here */
4806                                 entity->variable.alignment = specifiers->alignment;
4807                         }
4808
4809                         if (specifiers->is_inline && is_type_valid(type)) {
4810                                 errorf(&env.source_position,
4811                                            "variable '%Y' declared 'inline'", env.symbol);
4812                         }
4813
4814                         entity->variable.thread_local = specifiers->thread_local;
4815
4816                         bool invalid_storage_class = false;
4817                         if (current_scope == file_scope) {
4818                                 if (specifiers->storage_class != STORAGE_CLASS_EXTERN &&
4819                                                 specifiers->storage_class != STORAGE_CLASS_NONE   &&
4820                                                 specifiers->storage_class != STORAGE_CLASS_STATIC) {
4821                                         invalid_storage_class = true;
4822                                 }
4823                         } else {
4824                                 if (specifiers->thread_local &&
4825                                                 specifiers->storage_class == STORAGE_CLASS_NONE) {
4826                                         invalid_storage_class = true;
4827                                 }
4828                         }
4829                         if (invalid_storage_class) {
4830                                 errorf(&env.source_position,
4831                                                 "invalid storage class for variable '%Y'", env.symbol);
4832                         }
4833                 }
4834
4835                 entity->base.source_position          = env.source_position;
4836                 entity->base.symbol                   = env.symbol;
4837                 entity->base.namespc                  = NAMESPACE_NORMAL;
4838                 entity->declaration.type              = orig_type;
4839                 entity->declaration.modifiers         = env.modifiers;
4840                 entity->declaration.deprecated_string = specifiers->deprecated_string;
4841
4842                 storage_class_t storage_class = specifiers->storage_class;
4843                 entity->declaration.declared_storage_class = storage_class;
4844
4845                 if (storage_class == STORAGE_CLASS_NONE && current_scope != file_scope)
4846                         storage_class = STORAGE_CLASS_AUTO;
4847                 entity->declaration.storage_class = storage_class;
4848         }
4849
4850         parse_declaration_attributes(entity);
4851
4852         return entity;
4853 }
4854
4855 static type_t *parse_abstract_declarator(type_t *base_type)
4856 {
4857         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4858
4859         type_t *result = construct_declarator_type(construct_type, base_type);
4860         if (construct_type != NULL) {
4861                 obstack_free(&temp_obst, construct_type);
4862         }
4863
4864         return result;
4865 }
4866
4867 /**
4868  * Check if the declaration of main is suspicious.  main should be a
4869  * function with external linkage, returning int, taking either zero
4870  * arguments, two, or three arguments of appropriate types, ie.
4871  *
4872  * int main([ int argc, char **argv [, char **env ] ]).
4873  *
4874  * @param decl    the declaration to check
4875  * @param type    the function type of the declaration
4876  */
4877 static void check_type_of_main(const entity_t *entity)
4878 {
4879         const source_position_t *pos = &entity->base.source_position;
4880         if (entity->kind != ENTITY_FUNCTION) {
4881                 warningf(pos, "'main' is not a function");
4882                 return;
4883         }
4884
4885         if (entity->declaration.storage_class == STORAGE_CLASS_STATIC) {
4886                 warningf(pos, "'main' is normally a non-static function");
4887         }
4888
4889         type_t *type = skip_typeref(entity->declaration.type);
4890         assert(is_type_function(type));
4891
4892         function_type_t *func_type = &type->function;
4893         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4894                 warningf(pos, "return type of 'main' should be 'int', but is '%T'",
4895                          func_type->return_type);
4896         }
4897         const function_parameter_t *parm = func_type->parameters;
4898         if (parm != NULL) {
4899                 type_t *const first_type = parm->type;
4900                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4901                         warningf(pos,
4902                                  "first argument of 'main' should be 'int', but is '%T'",
4903                                  first_type);
4904                 }
4905                 parm = parm->next;
4906                 if (parm != NULL) {
4907                         type_t *const second_type = parm->type;
4908                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4909                                 warningf(pos, "second argument of 'main' should be 'char**', but is '%T'", second_type);
4910                         }
4911                         parm = parm->next;
4912                         if (parm != NULL) {
4913                                 type_t *const third_type = parm->type;
4914                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4915                                         warningf(pos, "third argument of 'main' should be 'char**', but is '%T'", third_type);
4916                                 }
4917                                 parm = parm->next;
4918                                 if (parm != NULL)
4919                                         goto warn_arg_count;
4920                         }
4921                 } else {
4922 warn_arg_count:
4923                         warningf(pos, "'main' takes only zero, two or three arguments");
4924                 }
4925         }
4926 }
4927
4928 /**
4929  * Check if a symbol is the equal to "main".
4930  */
4931 static bool is_sym_main(const symbol_t *const sym)
4932 {
4933         return strcmp(sym->string, "main") == 0;
4934 }
4935
4936 static void error_redefined_as_different_kind(const source_position_t *pos,
4937                 const entity_t *old, entity_kind_t new_kind)
4938 {
4939         errorf(pos, "redeclaration of %s '%Y' as %s (declared %P)",
4940                get_entity_kind_name(old->kind), old->base.symbol,
4941                get_entity_kind_name(new_kind), &old->base.source_position);
4942 }
4943
4944 /**
4945  * record entities for the NAMESPACE_NORMAL, and produce error messages/warnings
4946  * for various problems that occur for multiple definitions
4947  */
4948 static entity_t *record_entity(entity_t *entity, const bool is_definition)
4949 {
4950         const symbol_t *const    symbol  = entity->base.symbol;
4951         const namespace_tag_t    namespc = (namespace_tag_t)entity->base.namespc;
4952         const source_position_t *pos     = &entity->base.source_position;
4953
4954         /* can happen in error cases */
4955         if (symbol == NULL)
4956                 return entity;
4957
4958         entity_t *previous_entity = get_entity(symbol, namespc);
4959         /* pushing the same entity twice will break the stack structure */
4960         assert(previous_entity != entity);
4961
4962         if (entity->kind == ENTITY_FUNCTION) {
4963                 type_t *const orig_type = entity->declaration.type;
4964                 type_t *const type      = skip_typeref(orig_type);
4965
4966                 assert(is_type_function(type));
4967                 if (type->function.unspecified_parameters &&
4968                                 warning.strict_prototypes &&
4969                                 previous_entity == NULL) {
4970                         warningf(pos, "function declaration '%#T' is not a prototype",
4971                                          orig_type, symbol);
4972                 }
4973
4974                 if (warning.main && current_scope == file_scope
4975                                 && is_sym_main(symbol)) {
4976                         check_type_of_main(entity);
4977                 }
4978         }
4979
4980         if (is_declaration(entity) &&
4981                         warning.nested_externs &&
4982                         entity->declaration.storage_class == STORAGE_CLASS_EXTERN &&
4983                         current_scope != file_scope) {
4984                 warningf(pos, "nested extern declaration of '%#T'",
4985                          entity->declaration.type, symbol);
4986         }
4987
4988         if (previous_entity != NULL &&
4989                         previous_entity->base.parent_scope == &current_function->parameters &&
4990                         previous_entity->base.parent_scope->depth + 1 == current_scope->depth) {
4991                 assert(previous_entity->kind == ENTITY_PARAMETER);
4992                 errorf(pos,
4993                        "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
4994                                          entity->declaration.type, symbol,
4995                                          previous_entity->declaration.type, symbol,
4996                                          &previous_entity->base.source_position);
4997                 goto finish;
4998         }
4999
5000         if (previous_entity != NULL &&
5001                         previous_entity->base.parent_scope == current_scope) {
5002                 if (previous_entity->kind != entity->kind) {
5003                         error_redefined_as_different_kind(pos, previous_entity,
5004                                                           entity->kind);
5005                         goto finish;
5006                 }
5007                 if (previous_entity->kind == ENTITY_ENUM_VALUE) {
5008                         errorf(pos, "redeclaration of enum entry '%Y' (declared %P)",
5009                                    symbol, &previous_entity->base.source_position);
5010                         goto finish;
5011                 }
5012                 if (previous_entity->kind == ENTITY_TYPEDEF) {
5013                         /* TODO: C++ allows this for exactly the same type */
5014                         errorf(pos, "redefinition of typedef '%Y' (declared %P)",
5015                                symbol, &previous_entity->base.source_position);
5016                         goto finish;
5017                 }
5018
5019                 /* at this point we should have only VARIABLES or FUNCTIONS */
5020                 assert(is_declaration(previous_entity) && is_declaration(entity));
5021
5022                 declaration_t *const prev_decl = &previous_entity->declaration;
5023                 declaration_t *const decl      = &entity->declaration;
5024
5025                 /* can happen for K&R style declarations */
5026                 if (prev_decl->type       == NULL             &&
5027                                 previous_entity->kind == ENTITY_PARAMETER &&
5028                                 entity->kind          == ENTITY_PARAMETER) {
5029                         prev_decl->type                   = decl->type;
5030                         prev_decl->storage_class          = decl->storage_class;
5031                         prev_decl->declared_storage_class = decl->declared_storage_class;
5032                         prev_decl->modifiers              = decl->modifiers;
5033                         prev_decl->deprecated_string      = decl->deprecated_string;
5034                         return previous_entity;
5035                 }
5036
5037                 type_t *const orig_type = decl->type;
5038                 assert(orig_type != NULL);
5039                 type_t *const type      = skip_typeref(orig_type);
5040                 type_t *      prev_type = skip_typeref(prev_decl->type);
5041
5042                 if (!types_compatible(type, prev_type)) {
5043                         errorf(pos,
5044                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
5045                                    orig_type, symbol, prev_decl->type, symbol,
5046                                    &previous_entity->base.source_position);
5047                 } else {
5048                         unsigned old_storage_class = prev_decl->storage_class;
5049                         if (warning.redundant_decls               &&
5050                                         is_definition                     &&
5051                                         !prev_decl->used                  &&
5052                                         !(prev_decl->modifiers & DM_USED) &&
5053                                         prev_decl->storage_class == STORAGE_CLASS_STATIC) {
5054                                 warningf(&previous_entity->base.source_position,
5055                                          "unnecessary static forward declaration for '%#T'",
5056                                          prev_decl->type, symbol);
5057                         }
5058
5059                         unsigned new_storage_class = decl->storage_class;
5060                         if (is_type_incomplete(prev_type)) {
5061                                 prev_decl->type = type;
5062                                 prev_type       = type;
5063                         }
5064
5065                         /* pretend no storage class means extern for function
5066                          * declarations (except if the previous declaration is neither
5067                          * none nor extern) */
5068                         if (entity->kind == ENTITY_FUNCTION) {
5069                                 if (prev_type->function.unspecified_parameters) {
5070                                         prev_decl->type = type;
5071                                         prev_type       = type;
5072                                 }
5073
5074                                 switch (old_storage_class) {
5075                                 case STORAGE_CLASS_NONE:
5076                                         old_storage_class = STORAGE_CLASS_EXTERN;
5077                                         /* FALLTHROUGH */
5078
5079                                 case STORAGE_CLASS_EXTERN:
5080                                         if (is_definition) {
5081                                                 if (warning.missing_prototypes &&
5082                                                     prev_type->function.unspecified_parameters &&
5083                                                     !is_sym_main(symbol)) {
5084                                                         warningf(pos, "no previous prototype for '%#T'",
5085                                                                          orig_type, symbol);
5086                                                 }
5087                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
5088                                                 new_storage_class = STORAGE_CLASS_EXTERN;
5089                                         }
5090                                         break;
5091
5092                                 default:
5093                                         break;
5094                                 }
5095                         }
5096
5097                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
5098                                         new_storage_class == STORAGE_CLASS_EXTERN) {
5099 warn_redundant_declaration:
5100                                 if (!is_definition           &&
5101                                     warning.redundant_decls  &&
5102                                     is_type_valid(prev_type) &&
5103                                     strcmp(previous_entity->base.source_position.input_name,
5104                                            "<builtin>") != 0) {
5105                                         warningf(pos,
5106                                                  "redundant declaration for '%Y' (declared %P)",
5107                                                  symbol, &previous_entity->base.source_position);
5108                                 }
5109                         } else if (current_function == NULL) {
5110                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
5111                                     new_storage_class == STORAGE_CLASS_STATIC) {
5112                                         errorf(pos,
5113                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
5114                                                symbol, &previous_entity->base.source_position);
5115                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
5116                                         prev_decl->storage_class          = STORAGE_CLASS_NONE;
5117                                         prev_decl->declared_storage_class = STORAGE_CLASS_NONE;
5118                                 } else {
5119                                         /* ISO/IEC 14882:1998(E) §C.1.2:1 */
5120                                         if (c_mode & _CXX)
5121                                                 goto error_redeclaration;
5122                                         goto warn_redundant_declaration;
5123                                 }
5124                         } else if (is_type_valid(prev_type)) {
5125                                 if (old_storage_class == new_storage_class) {
5126 error_redeclaration:
5127                                         errorf(pos, "redeclaration of '%Y' (declared %P)",
5128                                                symbol, &previous_entity->base.source_position);
5129                                 } else {
5130                                         errorf(pos,
5131                                                "redeclaration of '%Y' with different linkage (declared %P)",
5132                                                symbol, &previous_entity->base.source_position);
5133                                 }
5134                         }
5135                 }
5136
5137                 prev_decl->modifiers |= decl->modifiers;
5138                 if (entity->kind == ENTITY_FUNCTION) {
5139                         previous_entity->function.is_inline |= entity->function.is_inline;
5140                 }
5141                 return previous_entity;
5142         }
5143
5144         if (entity->kind == ENTITY_FUNCTION) {
5145                 if (is_definition &&
5146                                 entity->declaration.storage_class != STORAGE_CLASS_STATIC) {
5147                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
5148                                 warningf(pos, "no previous prototype for '%#T'",
5149                                          entity->declaration.type, symbol);
5150                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
5151                                 warningf(pos, "no previous declaration for '%#T'",
5152                                          entity->declaration.type, symbol);
5153                         }
5154                 }
5155         } else if (warning.missing_declarations &&
5156                         entity->kind == ENTITY_VARIABLE &&
5157                         current_scope == file_scope) {
5158                 declaration_t *declaration = &entity->declaration;
5159                 if (declaration->storage_class == STORAGE_CLASS_NONE) {
5160                         warningf(pos, "no previous declaration for '%#T'",
5161                                  declaration->type, symbol);
5162                 }
5163         }
5164
5165 finish:
5166         assert(entity->base.parent_scope == NULL);
5167         assert(current_scope != NULL);
5168
5169         entity->base.parent_scope = current_scope;
5170         entity->base.namespc      = NAMESPACE_NORMAL;
5171         environment_push(entity);
5172         append_entity(current_scope, entity);
5173
5174         return entity;
5175 }
5176
5177 static void parser_error_multiple_definition(entity_t *entity,
5178                 const source_position_t *source_position)
5179 {
5180         errorf(source_position, "multiple definition of '%Y' (declared %P)",
5181                entity->base.symbol, &entity->base.source_position);
5182 }
5183
5184 static bool is_declaration_specifier(const token_t *token,
5185                                      bool only_specifiers_qualifiers)
5186 {
5187         switch (token->type) {
5188                 TYPE_SPECIFIERS
5189                 TYPE_QUALIFIERS
5190                         return true;
5191                 case T_IDENTIFIER:
5192                         return is_typedef_symbol(token->v.symbol);
5193
5194                 case T___extension__:
5195                 STORAGE_CLASSES
5196                         return !only_specifiers_qualifiers;
5197
5198                 default:
5199                         return false;
5200         }
5201 }
5202
5203 static void parse_init_declarator_rest(entity_t *entity)
5204 {
5205         assert(is_declaration(entity));
5206         declaration_t *const declaration = &entity->declaration;
5207
5208         eat('=');
5209
5210         type_t *orig_type = declaration->type;
5211         type_t *type      = skip_typeref(orig_type);
5212
5213         if (entity->kind == ENTITY_VARIABLE
5214                         && entity->variable.initializer != NULL) {
5215                 parser_error_multiple_definition(entity, HERE);
5216         }
5217
5218         bool must_be_constant = false;
5219         if (declaration->storage_class == STORAGE_CLASS_STATIC ||
5220             entity->base.parent_scope  == file_scope) {
5221                 must_be_constant = true;
5222         }
5223
5224         if (is_type_function(type)) {
5225                 errorf(&entity->base.source_position,
5226                        "function '%#T' is initialized like a variable",
5227                        orig_type, entity->base.symbol);
5228                 orig_type = type_error_type;
5229         }
5230
5231         parse_initializer_env_t env;
5232         env.type             = orig_type;
5233         env.must_be_constant = must_be_constant;
5234         env.entity           = entity;
5235         current_init_decl    = entity;
5236
5237         initializer_t *initializer = parse_initializer(&env);
5238         current_init_decl = NULL;
5239
5240         if (entity->kind == ENTITY_VARIABLE) {
5241                 /* § 6.7.5 (22)  array initializers for arrays with unknown size
5242                  * determine the array type size */
5243                 declaration->type            = env.type;
5244                 entity->variable.initializer = initializer;
5245         }
5246 }
5247
5248 /* parse rest of a declaration without any declarator */
5249 static void parse_anonymous_declaration_rest(
5250                 const declaration_specifiers_t *specifiers)
5251 {
5252         eat(';');
5253         anonymous_entity = NULL;
5254
5255         if (warning.other) {
5256                 if (specifiers->storage_class != STORAGE_CLASS_NONE ||
5257                                 specifiers->thread_local) {
5258                         warningf(&specifiers->source_position,
5259                                  "useless storage class in empty declaration");
5260                 }
5261
5262                 type_t *type = specifiers->type;
5263                 switch (type->kind) {
5264                         case TYPE_COMPOUND_STRUCT:
5265                         case TYPE_COMPOUND_UNION: {
5266                                 if (type->compound.compound->base.symbol == NULL) {
5267                                         warningf(&specifiers->source_position,
5268                                                  "unnamed struct/union that defines no instances");
5269                                 }
5270                                 break;
5271                         }
5272
5273                         case TYPE_ENUM:
5274                                 break;
5275
5276                         default:
5277                                 warningf(&specifiers->source_position, "empty declaration");
5278                                 break;
5279                 }
5280         }
5281 }
5282
5283 static void check_variable_type_complete(entity_t *ent)
5284 {
5285         if (ent->kind != ENTITY_VARIABLE)
5286                 return;
5287
5288         /* §6.7:7  If an identifier for an object is declared with no linkage, the
5289          *         type for the object shall be complete [...] */
5290         declaration_t *decl = &ent->declaration;
5291         if (decl->storage_class != STORAGE_CLASS_NONE)
5292                 return;
5293
5294         type_t *const orig_type = decl->type;
5295         type_t *const type      = skip_typeref(orig_type);
5296         if (!is_type_incomplete(type))
5297                 return;
5298
5299         /* GCC allows global arrays without size and assigns them a length of one,
5300          * if no different declaration follows */
5301         if (is_type_array(type) &&
5302                         c_mode & _GNUC      &&
5303                         ent->base.parent_scope == file_scope) {
5304                 ARR_APP1(declaration_t*, incomplete_arrays, decl);
5305                 return;
5306         }
5307
5308         errorf(&ent->base.source_position, "variable '%#T' has incomplete type",
5309                         orig_type, ent->base.symbol);
5310 }
5311
5312
5313 static void parse_declaration_rest(entity_t *ndeclaration,
5314                 const declaration_specifiers_t *specifiers,
5315                 parsed_declaration_func         finished_declaration,
5316                 declarator_flags_t              flags)
5317 {
5318         add_anchor_token(';');
5319         add_anchor_token(',');
5320         while (true) {
5321                 entity_t *entity = finished_declaration(ndeclaration, token.type == '=');
5322
5323                 if (token.type == '=') {
5324                         parse_init_declarator_rest(entity);
5325                 } else if (entity->kind == ENTITY_VARIABLE) {
5326                         /* ISO/IEC 14882:1998(E) §8.5.3:3  The initializer can be omitted
5327                          * [...] where the extern specifier is explicitly used. */
5328                         declaration_t *decl = &entity->declaration;
5329                         if (decl->storage_class != STORAGE_CLASS_EXTERN) {
5330                                 type_t *type = decl->type;
5331                                 if (is_type_reference(skip_typeref(type))) {
5332                                         errorf(&entity->base.source_position,
5333                                                         "reference '%#T' must be initialized",
5334                                                         type, entity->base.symbol);
5335                                 }
5336                         }
5337                 }
5338
5339                 check_variable_type_complete(entity);
5340
5341                 if (token.type != ',')
5342                         break;
5343                 eat(',');
5344
5345                 add_anchor_token('=');
5346                 ndeclaration = parse_declarator(specifiers, flags);
5347                 rem_anchor_token('=');
5348         }
5349         expect(';', end_error);
5350
5351 end_error:
5352         anonymous_entity = NULL;
5353         rem_anchor_token(';');
5354         rem_anchor_token(',');
5355 }
5356
5357 static entity_t *finished_kr_declaration(entity_t *entity, bool is_definition)
5358 {
5359         symbol_t *symbol = entity->base.symbol;
5360         if (symbol == NULL) {
5361                 errorf(HERE, "anonymous declaration not valid as function parameter");
5362                 return entity;
5363         }
5364
5365         assert(entity->base.namespc == NAMESPACE_NORMAL);
5366         entity_t *previous_entity = get_entity(symbol, NAMESPACE_NORMAL);
5367         if (previous_entity == NULL
5368                         || previous_entity->base.parent_scope != current_scope) {
5369                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
5370                        symbol);
5371                 return entity;
5372         }
5373
5374         if (is_definition) {
5375                 errorf(HERE, "parameter '%Y' is initialised", entity->base.symbol);
5376         }
5377
5378         return record_entity(entity, false);
5379 }
5380
5381 static void parse_declaration(parsed_declaration_func finished_declaration,
5382                               declarator_flags_t      flags)
5383 {
5384         declaration_specifiers_t specifiers;
5385         memset(&specifiers, 0, sizeof(specifiers));
5386
5387         add_anchor_token(';');
5388         parse_declaration_specifiers(&specifiers);
5389         rem_anchor_token(';');
5390
5391         if (token.type == ';') {
5392                 parse_anonymous_declaration_rest(&specifiers);
5393         } else {
5394                 entity_t *entity = parse_declarator(&specifiers, flags);
5395                 parse_declaration_rest(entity, &specifiers, finished_declaration, flags);
5396         }
5397 }
5398
5399 static type_t *get_default_promoted_type(type_t *orig_type)
5400 {
5401         type_t *result = orig_type;
5402
5403         type_t *type = skip_typeref(orig_type);
5404         if (is_type_integer(type)) {
5405                 result = promote_integer(type);
5406         } else if (type == type_float) {
5407                 result = type_double;
5408         }
5409
5410         return result;
5411 }
5412
5413 static void parse_kr_declaration_list(entity_t *entity)
5414 {
5415         if (entity->kind != ENTITY_FUNCTION)
5416                 return;
5417
5418         type_t *type = skip_typeref(entity->declaration.type);
5419         assert(is_type_function(type));
5420         if (!type->function.kr_style_parameters)
5421                 return;
5422
5423
5424         add_anchor_token('{');
5425
5426         /* push function parameters */
5427         size_t const  top       = environment_top();
5428         scope_t      *old_scope = scope_push(&entity->function.parameters);
5429
5430         entity_t *parameter = entity->function.parameters.entities;
5431         for ( ; parameter != NULL; parameter = parameter->base.next) {
5432                 assert(parameter->base.parent_scope == NULL);
5433                 parameter->base.parent_scope = current_scope;
5434                 environment_push(parameter);
5435         }
5436
5437         /* parse declaration list */
5438         for (;;) {
5439                 switch (token.type) {
5440                         DECLARATION_START
5441                         case T___extension__:
5442                         /* This covers symbols, which are no type, too, and results in
5443                          * better error messages.  The typical cases are misspelled type
5444                          * names and missing includes. */
5445                         case T_IDENTIFIER:
5446                                 parse_declaration(finished_kr_declaration, DECL_IS_PARAMETER);
5447                                 break;
5448                         default:
5449                                 goto decl_list_end;
5450                 }
5451         }
5452 decl_list_end:
5453
5454         /* pop function parameters */
5455         assert(current_scope == &entity->function.parameters);
5456         scope_pop(old_scope);
5457         environment_pop_to(top);
5458
5459         /* update function type */
5460         type_t *new_type = duplicate_type(type);
5461
5462         function_parameter_t *parameters     = NULL;
5463         function_parameter_t *last_parameter = NULL;
5464
5465         parameter = entity->function.parameters.entities;
5466         for (; parameter != NULL; parameter = parameter->base.next) {
5467                 type_t *parameter_type = parameter->declaration.type;
5468                 if (parameter_type == NULL) {
5469                         if (strict_mode) {
5470                                 errorf(HERE, "no type specified for function parameter '%Y'",
5471                                        parameter->base.symbol);
5472                         } else {
5473                                 if (warning.implicit_int) {
5474                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
5475                                                  parameter->base.symbol);
5476                                 }
5477                                 parameter_type              = type_int;
5478                                 parameter->declaration.type = parameter_type;
5479                         }
5480                 }
5481
5482                 semantic_parameter_incomplete(parameter);
5483                 parameter_type = parameter->declaration.type;
5484
5485                 /*
5486                  * we need the default promoted types for the function type
5487                  */
5488                 parameter_type = get_default_promoted_type(parameter_type);
5489
5490                 function_parameter_t *function_parameter
5491                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
5492                 memset(function_parameter, 0, sizeof(function_parameter[0]));
5493
5494                 function_parameter->type = parameter_type;
5495                 if (last_parameter != NULL) {
5496                         last_parameter->next = function_parameter;
5497                 } else {
5498                         parameters = function_parameter;
5499                 }
5500                 last_parameter = function_parameter;
5501         }
5502
5503         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
5504          * prototype */
5505         new_type->function.parameters             = parameters;
5506         new_type->function.unspecified_parameters = true;
5507
5508         type = typehash_insert(new_type);
5509         if (type != new_type) {
5510                 obstack_free(type_obst, new_type);
5511         }
5512
5513         entity->declaration.type = type;
5514
5515         rem_anchor_token('{');
5516 }
5517
5518 static bool first_err = true;
5519
5520 /**
5521  * When called with first_err set, prints the name of the current function,
5522  * else does noting.
5523  */
5524 static void print_in_function(void)
5525 {
5526         if (first_err) {
5527                 first_err = false;
5528                 diagnosticf("%s: In function '%Y':\n",
5529                             current_function->base.base.source_position.input_name,
5530                             current_function->base.base.symbol);
5531         }
5532 }
5533
5534 /**
5535  * Check if all labels are defined in the current function.
5536  * Check if all labels are used in the current function.
5537  */
5538 static void check_labels(void)
5539 {
5540         for (const goto_statement_t *goto_statement = goto_first;
5541             goto_statement != NULL;
5542             goto_statement = goto_statement->next) {
5543                 /* skip computed gotos */
5544                 if (goto_statement->expression != NULL)
5545                         continue;
5546
5547                 label_t *label = goto_statement->label;
5548
5549                 label->used = true;
5550                 if (label->base.source_position.input_name == NULL) {
5551                         print_in_function();
5552                         errorf(&goto_statement->base.source_position,
5553                                "label '%Y' used but not defined", label->base.symbol);
5554                  }
5555         }
5556
5557         if (warning.unused_label) {
5558                 for (const label_statement_t *label_statement = label_first;
5559                          label_statement != NULL;
5560                          label_statement = label_statement->next) {
5561                         label_t *label = label_statement->label;
5562
5563                         if (! label->used) {
5564                                 print_in_function();
5565                                 warningf(&label_statement->base.source_position,
5566                                          "label '%Y' defined but not used", label->base.symbol);
5567                         }
5568                 }
5569         }
5570 }
5571
5572 static void warn_unused_entity(entity_t *entity, entity_t *end)
5573 {
5574         for (; entity != NULL; entity = entity->base.next) {
5575                 if (!is_declaration(entity))
5576                         continue;
5577
5578                 declaration_t *declaration = &entity->declaration;
5579                 if (declaration->implicit)
5580                         continue;
5581
5582                 if (!declaration->used) {
5583                         print_in_function();
5584                         const char *what = get_entity_kind_name(entity->kind);
5585                         warningf(&entity->base.source_position, "%s '%Y' is unused",
5586                                  what, entity->base.symbol);
5587                 } else if (entity->kind == ENTITY_VARIABLE && !entity->variable.read) {
5588                         print_in_function();
5589                         const char *what = get_entity_kind_name(entity->kind);
5590                         warningf(&entity->base.source_position, "%s '%Y' is never read",
5591                                  what, entity->base.symbol);
5592                 }
5593
5594                 if (entity == end)
5595                         break;
5596         }
5597 }
5598
5599 static void check_unused_variables(statement_t *const stmt, void *const env)
5600 {
5601         (void)env;
5602
5603         switch (stmt->kind) {
5604                 case STATEMENT_DECLARATION: {
5605                         declaration_statement_t const *const decls = &stmt->declaration;
5606                         warn_unused_entity(decls->declarations_begin,
5607                                            decls->declarations_end);
5608                         return;
5609                 }
5610
5611                 case STATEMENT_FOR:
5612                         warn_unused_entity(stmt->fors.scope.entities, NULL);
5613                         return;
5614
5615                 default:
5616                         return;
5617         }
5618 }
5619
5620 /**
5621  * Check declarations of current_function for unused entities.
5622  */
5623 static void check_declarations(void)
5624 {
5625         if (warning.unused_parameter) {
5626                 const scope_t *scope = &current_function->parameters;
5627
5628                 /* do not issue unused warnings for main */
5629                 if (!is_sym_main(current_function->base.base.symbol)) {
5630                         warn_unused_entity(scope->entities, NULL);
5631                 }
5632         }
5633         if (warning.unused_variable) {
5634                 walk_statements(current_function->statement, check_unused_variables,
5635                                 NULL);
5636         }
5637 }
5638
5639 static int determine_truth(expression_t const* const cond)
5640 {
5641         return
5642                 !is_constant_expression(cond) ? 0 :
5643                 fold_constant(cond) != 0      ? 1 :
5644                 -1;
5645 }
5646
5647 static void check_reachable(statement_t *);
5648
5649 static bool expression_returns(expression_t const *const expr)
5650 {
5651         switch (expr->kind) {
5652                 case EXPR_CALL: {
5653                         expression_t const *const func = expr->call.function;
5654                         if (func->kind == EXPR_REFERENCE) {
5655                                 entity_t *entity = func->reference.entity;
5656                                 if (entity->kind == ENTITY_FUNCTION
5657                                                 && entity->declaration.modifiers & DM_NORETURN)
5658                                         return false;
5659                         }
5660
5661                         if (!expression_returns(func))
5662                                 return false;
5663
5664                         for (call_argument_t const* arg = expr->call.arguments; arg != NULL; arg = arg->next) {
5665                                 if (!expression_returns(arg->expression))
5666                                         return false;
5667                         }
5668
5669                         return true;
5670                 }
5671
5672                 case EXPR_REFERENCE:
5673                 case EXPR_REFERENCE_ENUM_VALUE:
5674                 case EXPR_CONST:
5675                 case EXPR_CHARACTER_CONSTANT:
5676                 case EXPR_WIDE_CHARACTER_CONSTANT:
5677                 case EXPR_STRING_LITERAL:
5678                 case EXPR_WIDE_STRING_LITERAL:
5679                 case EXPR_COMPOUND_LITERAL: // TODO descend into initialisers
5680                 case EXPR_LABEL_ADDRESS:
5681                 case EXPR_CLASSIFY_TYPE:
5682                 case EXPR_SIZEOF: // TODO handle obscure VLA case
5683                 case EXPR_ALIGNOF:
5684                 case EXPR_FUNCNAME:
5685                 case EXPR_BUILTIN_SYMBOL:
5686                 case EXPR_BUILTIN_CONSTANT_P:
5687                 case EXPR_BUILTIN_PREFETCH:
5688                 case EXPR_OFFSETOF:
5689                 case EXPR_INVALID:
5690                         return true;
5691
5692                 case EXPR_STATEMENT:
5693                         check_reachable(expr->statement.statement);
5694                         // TODO check if statement can be left
5695                         return true;
5696
5697                 case EXPR_CONDITIONAL:
5698                         // TODO handle constant expression
5699
5700                         if (!expression_returns(expr->conditional.condition))
5701                                 return false;
5702
5703                         if (expr->conditional.true_expression != NULL
5704                                         && expression_returns(expr->conditional.true_expression))
5705                                 return true;
5706
5707                         return expression_returns(expr->conditional.false_expression);
5708
5709                 case EXPR_SELECT:
5710                         return expression_returns(expr->select.compound);
5711
5712                 case EXPR_ARRAY_ACCESS:
5713                         return
5714                                 expression_returns(expr->array_access.array_ref) &&
5715                                 expression_returns(expr->array_access.index);
5716
5717                 case EXPR_VA_START:
5718                         return expression_returns(expr->va_starte.ap);
5719
5720                 case EXPR_VA_ARG:
5721                         return expression_returns(expr->va_arge.ap);
5722
5723                 EXPR_UNARY_CASES_MANDATORY
5724                         return expression_returns(expr->unary.value);
5725
5726                 case EXPR_UNARY_THROW:
5727                         return false;
5728
5729                 EXPR_BINARY_CASES
5730                         // TODO handle constant lhs of && and ||
5731                         return
5732                                 expression_returns(expr->binary.left) &&
5733                                 expression_returns(expr->binary.right);
5734
5735                 case EXPR_UNKNOWN:
5736                         break;
5737         }
5738
5739         panic("unhandled expression");
5740 }
5741
5742 static bool initializer_returns(initializer_t const *const init)
5743 {
5744         switch (init->kind) {
5745                 case INITIALIZER_VALUE:
5746                         return expression_returns(init->value.value);
5747
5748                 case INITIALIZER_LIST: {
5749                         initializer_t * const*       i       = init->list.initializers;
5750                         initializer_t * const* const end     = i + init->list.len;
5751                         bool                         returns = true;
5752                         for (; i != end; ++i) {
5753                                 if (!initializer_returns(*i))
5754                                         returns = false;
5755                         }
5756                         return returns;
5757                 }
5758
5759                 case INITIALIZER_STRING:
5760                 case INITIALIZER_WIDE_STRING:
5761                 case INITIALIZER_DESIGNATOR: // designators have no payload
5762                         return true;
5763         }
5764         panic("unhandled initializer");
5765 }
5766
5767 static bool noreturn_candidate;
5768
5769 static void check_reachable(statement_t *const stmt)
5770 {
5771         if (stmt->base.reachable)
5772                 return;
5773         if (stmt->kind != STATEMENT_DO_WHILE)
5774                 stmt->base.reachable = true;
5775
5776         statement_t *last = stmt;
5777         statement_t *next;
5778         switch (stmt->kind) {
5779                 case STATEMENT_INVALID:
5780                 case STATEMENT_EMPTY:
5781                 case STATEMENT_LOCAL_LABEL:
5782                 case STATEMENT_ASM:
5783                         next = stmt->base.next;
5784                         break;
5785
5786                 case STATEMENT_DECLARATION: {
5787                         declaration_statement_t const *const decl = &stmt->declaration;
5788                         entity_t                const *      ent  = decl->declarations_begin;
5789                         entity_t                const *const last = decl->declarations_end;
5790                         if (ent != NULL) {
5791                                 for (;; ent = ent->base.next) {
5792                                         if (ent->kind                 == ENTITY_VARIABLE &&
5793                                                         ent->variable.initializer != NULL            &&
5794                                                         !initializer_returns(ent->variable.initializer)) {
5795                                                 return;
5796                                         }
5797                                         if (ent == last)
5798                                                 break;
5799                                 }
5800                         }
5801                         next = stmt->base.next;
5802                         break;
5803                 }
5804
5805                 case STATEMENT_COMPOUND:
5806                         next = stmt->compound.statements;
5807                         break;
5808
5809                 case STATEMENT_RETURN: {
5810                         expression_t const *const val = stmt->returns.value;
5811                         if (val == NULL || expression_returns(val))
5812                                 noreturn_candidate = false;
5813                         return;
5814                 }
5815
5816                 case STATEMENT_IF: {
5817                         if_statement_t const *const ifs  = &stmt->ifs;
5818                         expression_t   const *const cond = ifs->condition;
5819
5820                         if (!expression_returns(cond))
5821                                 return;
5822
5823                         int const val = determine_truth(cond);
5824
5825                         if (val >= 0)
5826                                 check_reachable(ifs->true_statement);
5827
5828                         if (val > 0)
5829                                 return;
5830
5831                         if (ifs->false_statement != NULL) {
5832                                 check_reachable(ifs->false_statement);
5833                                 return;
5834                         }
5835
5836                         next = stmt->base.next;
5837                         break;
5838                 }
5839
5840                 case STATEMENT_SWITCH: {
5841                         switch_statement_t const *const switchs = &stmt->switchs;
5842                         expression_t       const *const expr    = switchs->expression;
5843
5844                         if (!expression_returns(expr))
5845                                 return;
5846
5847                         if (is_constant_expression(expr)) {
5848                                 long                    const val      = fold_constant(expr);
5849                                 case_label_statement_t *      defaults = NULL;
5850                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5851                                         if (i->expression == NULL) {
5852                                                 defaults = i;
5853                                                 continue;
5854                                         }
5855
5856                                         if (i->first_case <= val && val <= i->last_case) {
5857                                                 check_reachable((statement_t*)i);
5858                                                 return;
5859                                         }
5860                                 }
5861
5862                                 if (defaults != NULL) {
5863                                         check_reachable((statement_t*)defaults);
5864                                         return;
5865                                 }
5866                         } else {
5867                                 bool has_default = false;
5868                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5869                                         if (i->expression == NULL)
5870                                                 has_default = true;
5871
5872                                         check_reachable((statement_t*)i);
5873                                 }
5874
5875                                 if (has_default)
5876                                         return;
5877                         }
5878
5879                         next = stmt->base.next;
5880                         break;
5881                 }
5882
5883                 case STATEMENT_EXPRESSION: {
5884                         /* Check for noreturn function call */
5885                         expression_t const *const expr = stmt->expression.expression;
5886                         if (!expression_returns(expr))
5887                                 return;
5888
5889                         next = stmt->base.next;
5890                         break;
5891                 }
5892
5893                 case STATEMENT_CONTINUE: {
5894                         statement_t *parent = stmt;
5895                         for (;;) {
5896                                 parent = parent->base.parent;
5897                                 if (parent == NULL) /* continue not within loop */
5898                                         return;
5899
5900                                 next = parent;
5901                                 switch (parent->kind) {
5902                                         case STATEMENT_WHILE:    goto continue_while;
5903                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5904                                         case STATEMENT_FOR:      goto continue_for;
5905
5906                                         default: break;
5907                                 }
5908                         }
5909                 }
5910
5911                 case STATEMENT_BREAK: {
5912                         statement_t *parent = stmt;
5913                         for (;;) {
5914                                 parent = parent->base.parent;
5915                                 if (parent == NULL) /* break not within loop/switch */
5916                                         return;
5917
5918                                 switch (parent->kind) {
5919                                         case STATEMENT_SWITCH:
5920                                         case STATEMENT_WHILE:
5921                                         case STATEMENT_DO_WHILE:
5922                                         case STATEMENT_FOR:
5923                                                 last = parent;
5924                                                 next = parent->base.next;
5925                                                 goto found_break_parent;
5926
5927                                         default: break;
5928                                 }
5929                         }
5930 found_break_parent:
5931                         break;
5932                 }
5933
5934                 case STATEMENT_GOTO:
5935                         if (stmt->gotos.expression) {
5936                                 if (!expression_returns(stmt->gotos.expression))
5937                                         return;
5938
5939                                 statement_t *parent = stmt->base.parent;
5940                                 if (parent == NULL) /* top level goto */
5941                                         return;
5942                                 next = parent;
5943                         } else {
5944                                 next = stmt->gotos.label->statement;
5945                                 if (next == NULL) /* missing label */
5946                                         return;
5947                         }
5948                         break;
5949
5950                 case STATEMENT_LABEL:
5951                         next = stmt->label.statement;
5952                         break;
5953
5954                 case STATEMENT_CASE_LABEL:
5955                         next = stmt->case_label.statement;
5956                         break;
5957
5958                 case STATEMENT_WHILE: {
5959                         while_statement_t const *const whiles = &stmt->whiles;
5960                         expression_t      const *const cond   = whiles->condition;
5961
5962                         if (!expression_returns(cond))
5963                                 return;
5964
5965                         int const val = determine_truth(cond);
5966
5967                         if (val >= 0)
5968                                 check_reachable(whiles->body);
5969
5970                         if (val > 0)
5971                                 return;
5972
5973                         next = stmt->base.next;
5974                         break;
5975                 }
5976
5977                 case STATEMENT_DO_WHILE:
5978                         next = stmt->do_while.body;
5979                         break;
5980
5981                 case STATEMENT_FOR: {
5982                         for_statement_t *const fors = &stmt->fors;
5983
5984                         if (fors->condition_reachable)
5985                                 return;
5986                         fors->condition_reachable = true;
5987
5988                         expression_t const *const cond = fors->condition;
5989
5990                         int val;
5991                         if (cond == NULL) {
5992                                 val = 1;
5993                         } else if (expression_returns(cond)) {
5994                                 val = determine_truth(cond);
5995                         } else {
5996                                 return;
5997                         }
5998
5999                         if (val >= 0)
6000                                 check_reachable(fors->body);
6001
6002                         if (val > 0)
6003                                 return;
6004
6005                         next = stmt->base.next;
6006                         break;
6007                 }
6008
6009                 case STATEMENT_MS_TRY: {
6010                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
6011                         check_reachable(ms_try->try_statement);
6012                         next = ms_try->final_statement;
6013                         break;
6014                 }
6015
6016                 case STATEMENT_LEAVE: {
6017                         statement_t *parent = stmt;
6018                         for (;;) {
6019                                 parent = parent->base.parent;
6020                                 if (parent == NULL) /* __leave not within __try */
6021                                         return;
6022
6023                                 if (parent->kind == STATEMENT_MS_TRY) {
6024                                         last = parent;
6025                                         next = parent->ms_try.final_statement;
6026                                         break;
6027                                 }
6028                         }
6029                         break;
6030                 }
6031         }
6032
6033         while (next == NULL) {
6034                 next = last->base.parent;
6035                 if (next == NULL) {
6036                         noreturn_candidate = false;
6037
6038                         type_t *const type = current_function->base.type;
6039                         assert(is_type_function(type));
6040                         type_t *const ret  = skip_typeref(type->function.return_type);
6041                         if (warning.return_type                    &&
6042                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
6043                             is_type_valid(ret)                     &&
6044                             !is_sym_main(current_function->base.base.symbol)) {
6045                                 warningf(&stmt->base.source_position,
6046                                          "control reaches end of non-void function");
6047                         }
6048                         return;
6049                 }
6050
6051                 switch (next->kind) {
6052                         case STATEMENT_INVALID:
6053                         case STATEMENT_EMPTY:
6054                         case STATEMENT_DECLARATION:
6055                         case STATEMENT_LOCAL_LABEL:
6056                         case STATEMENT_EXPRESSION:
6057                         case STATEMENT_ASM:
6058                         case STATEMENT_RETURN:
6059                         case STATEMENT_CONTINUE:
6060                         case STATEMENT_BREAK:
6061                         case STATEMENT_GOTO:
6062                         case STATEMENT_LEAVE:
6063                                 panic("invalid control flow in function");
6064
6065                         case STATEMENT_COMPOUND:
6066                         case STATEMENT_IF:
6067                         case STATEMENT_SWITCH:
6068                         case STATEMENT_LABEL:
6069                         case STATEMENT_CASE_LABEL:
6070                                 last = next;
6071                                 next = next->base.next;
6072                                 break;
6073
6074                         case STATEMENT_WHILE: {
6075 continue_while:
6076                                 if (next->base.reachable)
6077                                         return;
6078                                 next->base.reachable = true;
6079
6080                                 while_statement_t const *const whiles = &next->whiles;
6081                                 expression_t      const *const cond   = whiles->condition;
6082
6083                                 if (!expression_returns(cond))
6084                                         return;
6085
6086                                 int const val = determine_truth(cond);
6087
6088                                 if (val >= 0)
6089                                         check_reachable(whiles->body);
6090
6091                                 if (val > 0)
6092                                         return;
6093
6094                                 last = next;
6095                                 next = next->base.next;
6096                                 break;
6097                         }
6098
6099                         case STATEMENT_DO_WHILE: {
6100 continue_do_while:
6101                                 if (next->base.reachable)
6102                                         return;
6103                                 next->base.reachable = true;
6104
6105                                 do_while_statement_t const *const dw   = &next->do_while;
6106                                 expression_t         const *const cond = dw->condition;
6107
6108                                 if (!expression_returns(cond))
6109                                         return;
6110
6111                                 int const val = determine_truth(cond);
6112
6113                                 if (val >= 0)
6114                                         check_reachable(dw->body);
6115
6116                                 if (val > 0)
6117                                         return;
6118
6119                                 last = next;
6120                                 next = next->base.next;
6121                                 break;
6122                         }
6123
6124                         case STATEMENT_FOR: {
6125 continue_for:;
6126                                 for_statement_t *const fors = &next->fors;
6127
6128                                 fors->step_reachable = true;
6129
6130                                 if (fors->condition_reachable)
6131                                         return;
6132                                 fors->condition_reachable = true;
6133
6134                                 expression_t const *const cond = fors->condition;
6135
6136                                 int val;
6137                                 if (cond == NULL) {
6138                                         val = 1;
6139                                 } else if (expression_returns(cond)) {
6140                                         val = determine_truth(cond);
6141                                 } else {
6142                                         return;
6143                                 }
6144
6145                                 if (val >= 0)
6146                                         check_reachable(fors->body);
6147
6148                                 if (val > 0)
6149                                         return;
6150
6151                                 last = next;
6152                                 next = next->base.next;
6153                                 break;
6154                         }
6155
6156                         case STATEMENT_MS_TRY:
6157                                 last = next;
6158                                 next = next->ms_try.final_statement;
6159                                 break;
6160                 }
6161         }
6162
6163         check_reachable(next);
6164 }
6165
6166 static void check_unreachable(statement_t* const stmt, void *const env)
6167 {
6168         (void)env;
6169
6170         switch (stmt->kind) {
6171                 case STATEMENT_DO_WHILE:
6172                         if (!stmt->base.reachable) {
6173                                 expression_t const *const cond = stmt->do_while.condition;
6174                                 if (determine_truth(cond) >= 0) {
6175                                         warningf(&cond->base.source_position,
6176                                                  "condition of do-while-loop is unreachable");
6177                                 }
6178                         }
6179                         return;
6180
6181                 case STATEMENT_FOR: {
6182                         for_statement_t const* const fors = &stmt->fors;
6183
6184                         // if init and step are unreachable, cond is unreachable, too
6185                         if (!stmt->base.reachable && !fors->step_reachable) {
6186                                 warningf(&stmt->base.source_position, "statement is unreachable");
6187                         } else {
6188                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
6189                                         warningf(&fors->initialisation->base.source_position,
6190                                                  "initialisation of for-statement is unreachable");
6191                                 }
6192
6193                                 if (!fors->condition_reachable && fors->condition != NULL) {
6194                                         warningf(&fors->condition->base.source_position,
6195                                                  "condition of for-statement is unreachable");
6196                                 }
6197
6198                                 if (!fors->step_reachable && fors->step != NULL) {
6199                                         warningf(&fors->step->base.source_position,
6200                                                  "step of for-statement is unreachable");
6201                                 }
6202                         }
6203                         return;
6204                 }
6205
6206                 case STATEMENT_COMPOUND:
6207                         if (stmt->compound.statements != NULL)
6208                                 return;
6209                         goto warn_unreachable;
6210
6211                 case STATEMENT_DECLARATION: {
6212                         /* Only warn if there is at least one declarator with an initializer.
6213                          * This typically occurs in switch statements. */
6214                         declaration_statement_t const *const decl = &stmt->declaration;
6215                         entity_t                const *      ent  = decl->declarations_begin;
6216                         entity_t                const *const last = decl->declarations_end;
6217                         for (;; ent = ent->base.next) {
6218                                 if (ent->kind                 == ENTITY_VARIABLE &&
6219                                                 ent->variable.initializer != NULL) {
6220                                         goto warn_unreachable;
6221                                 }
6222                                 if (ent == last)
6223                                         return;
6224                         }
6225                 }
6226
6227                 default:
6228 warn_unreachable:
6229                         if (!stmt->base.reachable)
6230                                 warningf(&stmt->base.source_position, "statement is unreachable");
6231                         return;
6232         }
6233 }
6234
6235 static void parse_external_declaration(void)
6236 {
6237         /* function-definitions and declarations both start with declaration
6238          * specifiers */
6239         declaration_specifiers_t specifiers;
6240         memset(&specifiers, 0, sizeof(specifiers));
6241
6242         add_anchor_token(';');
6243         parse_declaration_specifiers(&specifiers);
6244         rem_anchor_token(';');
6245
6246         /* must be a declaration */
6247         if (token.type == ';') {
6248                 parse_anonymous_declaration_rest(&specifiers);
6249                 return;
6250         }
6251
6252         add_anchor_token(',');
6253         add_anchor_token('=');
6254         add_anchor_token(';');
6255         add_anchor_token('{');
6256
6257         /* declarator is common to both function-definitions and declarations */
6258         entity_t *ndeclaration = parse_declarator(&specifiers, DECL_FLAGS_NONE);
6259
6260         rem_anchor_token('{');
6261         rem_anchor_token(';');
6262         rem_anchor_token('=');
6263         rem_anchor_token(',');
6264
6265         /* must be a declaration */
6266         switch (token.type) {
6267                 case ',':
6268                 case ';':
6269                 case '=':
6270                         parse_declaration_rest(ndeclaration, &specifiers, record_entity,
6271                                         DECL_FLAGS_NONE);
6272                         return;
6273         }
6274
6275         /* must be a function definition */
6276         parse_kr_declaration_list(ndeclaration);
6277
6278         if (token.type != '{') {
6279                 parse_error_expected("while parsing function definition", '{', NULL);
6280                 eat_until_matching_token(';');
6281                 return;
6282         }
6283
6284         assert(is_declaration(ndeclaration));
6285         type_t *type = skip_typeref(ndeclaration->declaration.type);
6286
6287         if (!is_type_function(type)) {
6288                 if (is_type_valid(type)) {
6289                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
6290                                type, ndeclaration->base.symbol);
6291                 }
6292                 eat_block();
6293                 return;
6294         }
6295
6296         if (warning.aggregate_return &&
6297             is_type_compound(skip_typeref(type->function.return_type))) {
6298                 warningf(HERE, "function '%Y' returns an aggregate",
6299                          ndeclaration->base.symbol);
6300         }
6301         if (warning.traditional && !type->function.unspecified_parameters) {
6302                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
6303                         ndeclaration->base.symbol);
6304         }
6305         if (warning.old_style_definition && type->function.unspecified_parameters) {
6306                 warningf(HERE, "old-style function definition '%Y'",
6307                         ndeclaration->base.symbol);
6308         }
6309
6310         /* § 6.7.5.3 (14) a function definition with () means no
6311          * parameters (and not unspecified parameters) */
6312         if (type->function.unspecified_parameters
6313                         && type->function.parameters == NULL
6314                         && !type->function.kr_style_parameters) {
6315                 type_t *duplicate = duplicate_type(type);
6316                 duplicate->function.unspecified_parameters = false;
6317
6318                 type = typehash_insert(duplicate);
6319                 if (type != duplicate) {
6320                         obstack_free(type_obst, duplicate);
6321                 }
6322                 ndeclaration->declaration.type = type;
6323         }
6324
6325         entity_t *const entity = record_entity(ndeclaration, true);
6326         assert(entity->kind == ENTITY_FUNCTION);
6327         assert(ndeclaration->kind == ENTITY_FUNCTION);
6328
6329         function_t *function = &entity->function;
6330         if (ndeclaration != entity) {
6331                 function->parameters = ndeclaration->function.parameters;
6332         }
6333         assert(is_declaration(entity));
6334         type = skip_typeref(entity->declaration.type);
6335
6336         /* push function parameters and switch scope */
6337         size_t const  top       = environment_top();
6338         scope_t      *old_scope = scope_push(&function->parameters);
6339
6340         entity_t *parameter = function->parameters.entities;
6341         for (; parameter != NULL; parameter = parameter->base.next) {
6342                 if (parameter->base.parent_scope == &ndeclaration->function.parameters) {
6343                         parameter->base.parent_scope = current_scope;
6344                 }
6345                 assert(parameter->base.parent_scope == NULL
6346                                 || parameter->base.parent_scope == current_scope);
6347                 parameter->base.parent_scope = current_scope;
6348                 if (parameter->base.symbol == NULL) {
6349                         errorf(&parameter->base.source_position, "parameter name omitted");
6350                         continue;
6351                 }
6352                 environment_push(parameter);
6353         }
6354
6355         if (function->statement != NULL) {
6356                 parser_error_multiple_definition(entity, HERE);
6357                 eat_block();
6358         } else {
6359                 /* parse function body */
6360                 int         label_stack_top      = label_top();
6361                 function_t *old_current_function = current_function;
6362                 current_function                 = function;
6363                 current_parent                   = NULL;
6364
6365                 goto_first   = NULL;
6366                 goto_anchor  = &goto_first;
6367                 label_first  = NULL;
6368                 label_anchor = &label_first;
6369
6370                 statement_t *const body = parse_compound_statement(false);
6371                 function->statement = body;
6372                 first_err = true;
6373                 check_labels();
6374                 check_declarations();
6375                 if (warning.return_type      ||
6376                     warning.unreachable_code ||
6377                     (warning.missing_noreturn
6378                      && !(function->base.modifiers & DM_NORETURN))) {
6379                         noreturn_candidate = true;
6380                         check_reachable(body);
6381                         if (warning.unreachable_code)
6382                                 walk_statements(body, check_unreachable, NULL);
6383                         if (warning.missing_noreturn &&
6384                             noreturn_candidate       &&
6385                             !(function->base.modifiers & DM_NORETURN)) {
6386                                 warningf(&body->base.source_position,
6387                                          "function '%#T' is candidate for attribute 'noreturn'",
6388                                          type, entity->base.symbol);
6389                         }
6390                 }
6391
6392                 assert(current_parent   == NULL);
6393                 assert(current_function == function);
6394                 current_function = old_current_function;
6395                 label_pop_to(label_stack_top);
6396         }
6397
6398         assert(current_scope == &function->parameters);
6399         scope_pop(old_scope);
6400         environment_pop_to(top);
6401 }
6402
6403 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
6404                                   source_position_t *source_position,
6405                                   const symbol_t *symbol)
6406 {
6407         type_t *type = allocate_type_zero(TYPE_BITFIELD);
6408
6409         type->bitfield.base_type       = base_type;
6410         type->bitfield.size_expression = size;
6411
6412         il_size_t bit_size;
6413         type_t *skipped_type = skip_typeref(base_type);
6414         if (!is_type_integer(skipped_type)) {
6415                 errorf(HERE, "bitfield base type '%T' is not an integer type",
6416                         base_type);
6417                 bit_size = 0;
6418         } else {
6419                 bit_size = skipped_type->base.size * 8;
6420         }
6421
6422         if (is_constant_expression(size)) {
6423                 long v = fold_constant(size);
6424
6425                 if (v < 0) {
6426                         errorf(source_position, "negative width in bit-field '%Y'", symbol);
6427                 } else if (v == 0) {
6428                         errorf(source_position, "zero width for bit-field '%Y'", symbol);
6429                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
6430                         errorf(source_position, "width of '%Y' exceeds its type", symbol);
6431                 } else {
6432                         type->bitfield.bit_size = v;
6433                 }
6434         }
6435
6436         return type;
6437 }
6438
6439 static entity_t *find_compound_entry(compound_t *compound, symbol_t *symbol)
6440 {
6441         entity_t *iter = compound->members.entities;
6442         for (; iter != NULL; iter = iter->base.next) {
6443                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
6444                         continue;
6445
6446                 if (iter->base.symbol == symbol) {
6447                         return iter;
6448                 } else if (iter->base.symbol == NULL) {
6449                         type_t *type = skip_typeref(iter->declaration.type);
6450                         if (is_type_compound(type)) {
6451                                 entity_t *result
6452                                         = find_compound_entry(type->compound.compound, symbol);
6453                                 if (result != NULL)
6454                                         return result;
6455                         }
6456                         continue;
6457                 }
6458         }
6459
6460         return NULL;
6461 }
6462
6463 static void parse_compound_declarators(compound_t *compound,
6464                 const declaration_specifiers_t *specifiers)
6465 {
6466         while (true) {
6467                 entity_t *entity;
6468
6469                 if (token.type == ':') {
6470                         source_position_t source_position = *HERE;
6471                         next_token();
6472
6473                         type_t *base_type = specifiers->type;
6474                         expression_t *size = parse_constant_expression();
6475
6476                         type_t *type = make_bitfield_type(base_type, size,
6477                                         &source_position, sym_anonymous);
6478
6479                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
6480                         entity->base.namespc                       = NAMESPACE_NORMAL;
6481                         entity->base.source_position               = source_position;
6482                         entity->declaration.declared_storage_class = STORAGE_CLASS_NONE;
6483                         entity->declaration.storage_class          = STORAGE_CLASS_NONE;
6484                         entity->declaration.modifiers              = specifiers->modifiers;
6485                         entity->declaration.type                   = type;
6486                 } else {
6487                         entity = parse_declarator(specifiers,
6488                                         DECL_MAY_BE_ABSTRACT | DECL_CREATE_COMPOUND_MEMBER);
6489                         assert(entity->kind == ENTITY_COMPOUND_MEMBER);
6490
6491                         if (token.type == ':') {
6492                                 source_position_t source_position = *HERE;
6493                                 next_token();
6494                                 expression_t *size = parse_constant_expression();
6495
6496                                 type_t *type = entity->declaration.type;
6497                                 type_t *bitfield_type = make_bitfield_type(type, size,
6498                                                 &source_position, entity->base.symbol);
6499                                 entity->declaration.type = bitfield_type;
6500                         }
6501                 }
6502
6503                 /* make sure we don't define a symbol multiple times */
6504                 symbol_t *symbol = entity->base.symbol;
6505                 if (symbol != NULL) {
6506                         entity_t *prev = find_compound_entry(compound, symbol);
6507
6508                         if (prev != NULL) {
6509                                 errorf(&entity->base.source_position,
6510                                        "multiple declarations of symbol '%Y' (declared %P)",
6511                                        symbol, &prev->base.source_position);
6512                         }
6513                 }
6514
6515                 append_entity(&compound->members, entity);
6516
6517                 type_t *orig_type = entity->declaration.type;
6518                 type_t *type      = skip_typeref(orig_type);
6519                 if (is_type_function(type)) {
6520                         errorf(&entity->base.source_position,
6521                                         "compound member '%Y' must not have function type '%T'",
6522                                         entity->base.symbol, orig_type);
6523                 } else if (is_type_incomplete(type)) {
6524                         /* §6.7.2.1:16 flexible array member */
6525                         if (is_type_array(type) &&
6526                                         token.type == ';'   &&
6527                                         look_ahead(1)->type == '}') {
6528                                 compound->has_flexible_member = true;
6529                         } else {
6530                                 errorf(&entity->base.source_position,
6531                                                 "compound member '%Y' has incomplete type '%T'",
6532                                                 entity->base.symbol, orig_type);
6533                         }
6534                 }
6535
6536                 if (token.type != ',')
6537                         break;
6538                 next_token();
6539         }
6540         expect(';', end_error);
6541
6542 end_error:
6543         anonymous_entity = NULL;
6544 }
6545
6546 static void parse_compound_type_entries(compound_t *compound)
6547 {
6548         eat('{');
6549         add_anchor_token('}');
6550
6551         while (token.type != '}') {
6552                 if (token.type == T_EOF) {
6553                         errorf(HERE, "EOF while parsing struct");
6554                         break;
6555                 }
6556                 declaration_specifiers_t specifiers;
6557                 memset(&specifiers, 0, sizeof(specifiers));
6558                 parse_declaration_specifiers(&specifiers);
6559
6560                 parse_compound_declarators(compound, &specifiers);
6561         }
6562         rem_anchor_token('}');
6563         next_token();
6564
6565         /* §6.7.2.1:7 */
6566         compound->complete = true;
6567 }
6568
6569 static type_t *parse_typename(void)
6570 {
6571         declaration_specifiers_t specifiers;
6572         memset(&specifiers, 0, sizeof(specifiers));
6573         parse_declaration_specifiers(&specifiers);
6574         if (specifiers.storage_class != STORAGE_CLASS_NONE ||
6575                         specifiers.thread_local) {
6576                 /* TODO: improve error message, user does probably not know what a
6577                  * storage class is...
6578                  */
6579                 errorf(HERE, "typename may not have a storage class");
6580         }
6581
6582         type_t *result = parse_abstract_declarator(specifiers.type);
6583
6584         return result;
6585 }
6586
6587
6588
6589
6590 typedef expression_t* (*parse_expression_function)(void);
6591 typedef expression_t* (*parse_expression_infix_function)(expression_t *left);
6592
6593 typedef struct expression_parser_function_t expression_parser_function_t;
6594 struct expression_parser_function_t {
6595         parse_expression_function        parser;
6596         unsigned                         infix_precedence;
6597         parse_expression_infix_function  infix_parser;
6598 };
6599
6600 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
6601
6602 /**
6603  * Prints an error message if an expression was expected but not read
6604  */
6605 static expression_t *expected_expression_error(void)
6606 {
6607         /* skip the error message if the error token was read */
6608         if (token.type != T_ERROR) {
6609                 errorf(HERE, "expected expression, got token %K", &token);
6610         }
6611         next_token();
6612
6613         return create_invalid_expression();
6614 }
6615
6616 /**
6617  * Parse a string constant.
6618  */
6619 static expression_t *parse_string_const(void)
6620 {
6621         wide_string_t wres;
6622         if (token.type == T_STRING_LITERAL) {
6623                 string_t res = token.v.string;
6624                 next_token();
6625                 while (token.type == T_STRING_LITERAL) {
6626                         res = concat_strings(&res, &token.v.string);
6627                         next_token();
6628                 }
6629                 if (token.type != T_WIDE_STRING_LITERAL) {
6630                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
6631                         /* note: that we use type_char_ptr here, which is already the
6632                          * automatic converted type. revert_automatic_type_conversion
6633                          * will construct the array type */
6634                         cnst->base.type    = warning.write_strings ? type_const_char_ptr : type_char_ptr;
6635                         cnst->string.value = res;
6636                         return cnst;
6637                 }
6638
6639                 wres = concat_string_wide_string(&res, &token.v.wide_string);
6640         } else {
6641                 wres = token.v.wide_string;
6642         }
6643         next_token();
6644
6645         for (;;) {
6646                 switch (token.type) {
6647                         case T_WIDE_STRING_LITERAL:
6648                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
6649                                 break;
6650
6651                         case T_STRING_LITERAL:
6652                                 wres = concat_wide_string_string(&wres, &token.v.string);
6653                                 break;
6654
6655                         default: {
6656                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
6657                                 cnst->base.type         = warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
6658                                 cnst->wide_string.value = wres;
6659                                 return cnst;
6660                         }
6661                 }
6662                 next_token();
6663         }
6664 }
6665
6666 /**
6667  * Parse a boolean constant.
6668  */
6669 static expression_t *parse_bool_const(bool value)
6670 {
6671         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6672         cnst->base.type          = type_bool;
6673         cnst->conste.v.int_value = value;
6674
6675         next_token();
6676
6677         return cnst;
6678 }
6679
6680 /**
6681  * Parse an integer constant.
6682  */
6683 static expression_t *parse_int_const(void)
6684 {
6685         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
6686         cnst->base.type          = token.datatype;
6687         cnst->conste.v.int_value = token.v.intvalue;
6688
6689         next_token();
6690
6691         return cnst;
6692 }
6693
6694 /**
6695  * Parse a character constant.
6696  */
6697 static expression_t *parse_character_constant(void)
6698 {
6699         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
6700         cnst->base.type          = token.datatype;
6701         cnst->conste.v.character = token.v.string;
6702
6703         if (cnst->conste.v.character.size != 1) {
6704                 if (!GNU_MODE) {
6705                         errorf(HERE, "more than 1 character in character constant");
6706                 } else if (warning.multichar) {
6707                         warningf(HERE, "multi-character character constant");
6708                 }
6709         }
6710         next_token();
6711
6712         return cnst;
6713 }
6714
6715 /**
6716  * Parse a wide character constant.
6717  */
6718 static expression_t *parse_wide_character_constant(void)
6719 {
6720         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
6721         cnst->base.type               = token.datatype;
6722         cnst->conste.v.wide_character = token.v.wide_string;
6723
6724         if (cnst->conste.v.wide_character.size != 1) {
6725                 if (!GNU_MODE) {
6726                         errorf(HERE, "more than 1 character in character constant");
6727                 } else if (warning.multichar) {
6728                         warningf(HERE, "multi-character character constant");
6729                 }
6730         }
6731         next_token();
6732
6733         return cnst;
6734 }
6735
6736 /**
6737  * Parse a float constant.
6738  */
6739 static expression_t *parse_float_const(void)
6740 {
6741         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6742         cnst->base.type            = token.datatype;
6743         cnst->conste.v.float_value = token.v.floatvalue;
6744
6745         next_token();
6746
6747         return cnst;
6748 }
6749
6750 static entity_t *create_implicit_function(symbol_t *symbol,
6751                 const source_position_t *source_position)
6752 {
6753         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION);
6754         ntype->function.return_type            = type_int;
6755         ntype->function.unspecified_parameters = true;
6756
6757         type_t *type = typehash_insert(ntype);
6758         if (type != ntype) {
6759                 free_type(ntype);
6760         }
6761
6762         entity_t *entity = allocate_entity_zero(ENTITY_FUNCTION);
6763         entity->declaration.storage_class          = STORAGE_CLASS_EXTERN;
6764         entity->declaration.declared_storage_class = STORAGE_CLASS_EXTERN;
6765         entity->declaration.type                   = type;
6766         entity->declaration.implicit               = true;
6767         entity->base.symbol                        = symbol;
6768         entity->base.source_position               = *source_position;
6769
6770         bool strict_prototypes_old = warning.strict_prototypes;
6771         warning.strict_prototypes  = false;
6772         record_entity(entity, false);
6773         warning.strict_prototypes = strict_prototypes_old;
6774
6775         return entity;
6776 }
6777
6778 /**
6779  * Creates a return_type (func)(argument_type) function type if not
6780  * already exists.
6781  */
6782 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
6783                                     type_t *argument_type2)
6784 {
6785         function_parameter_t *parameter2
6786                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
6787         memset(parameter2, 0, sizeof(parameter2[0]));
6788         parameter2->type = argument_type2;
6789
6790         function_parameter_t *parameter1
6791                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
6792         memset(parameter1, 0, sizeof(parameter1[0]));
6793         parameter1->type = argument_type1;
6794         parameter1->next = parameter2;
6795
6796         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6797         type->function.return_type = return_type;
6798         type->function.parameters  = parameter1;
6799
6800         type_t *result = typehash_insert(type);
6801         if (result != type) {
6802                 free_type(type);
6803         }
6804
6805         return result;
6806 }
6807
6808 /**
6809  * Creates a return_type (func)(argument_type) function type if not
6810  * already exists.
6811  *
6812  * @param return_type    the return type
6813  * @param argument_type  the argument type
6814  */
6815 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
6816 {
6817         function_parameter_t *parameter
6818                 = obstack_alloc(type_obst, sizeof(parameter[0]));
6819         memset(parameter, 0, sizeof(parameter[0]));
6820         parameter->type = argument_type;
6821
6822         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6823         type->function.return_type = return_type;
6824         type->function.parameters  = parameter;
6825
6826         type_t *result = typehash_insert(type);
6827         if (result != type) {
6828                 free_type(type);
6829         }
6830
6831         return result;
6832 }
6833
6834 static type_t *make_function_0_type(type_t *return_type)
6835 {
6836         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
6837         type->function.return_type = return_type;
6838         type->function.parameters  = NULL;
6839
6840         type_t *result = typehash_insert(type);
6841         if (result != type) {
6842                 free_type(type);
6843         }
6844
6845         return result;
6846 }
6847
6848 /**
6849  * Creates a function type for some function like builtins.
6850  *
6851  * @param symbol   the symbol describing the builtin
6852  */
6853 static type_t *get_builtin_symbol_type(symbol_t *symbol)
6854 {
6855         switch (symbol->ID) {
6856         case T___builtin_alloca:
6857                 return make_function_1_type(type_void_ptr, type_size_t);
6858         case T___builtin_huge_val:
6859                 return make_function_0_type(type_double);
6860         case T___builtin_inf:
6861                 return make_function_0_type(type_double);
6862         case T___builtin_inff:
6863                 return make_function_0_type(type_float);
6864         case T___builtin_infl:
6865                 return make_function_0_type(type_long_double);
6866         case T___builtin_nan:
6867                 return make_function_1_type(type_double, type_char_ptr);
6868         case T___builtin_nanf:
6869                 return make_function_1_type(type_float, type_char_ptr);
6870         case T___builtin_nanl:
6871                 return make_function_1_type(type_long_double, type_char_ptr);
6872         case T___builtin_va_end:
6873                 return make_function_1_type(type_void, type_valist);
6874         case T___builtin_expect:
6875                 return make_function_2_type(type_long, type_long, type_long);
6876         default:
6877                 internal_errorf(HERE, "not implemented builtin identifier found");
6878         }
6879 }
6880
6881 /**
6882  * Performs automatic type cast as described in § 6.3.2.1.
6883  *
6884  * @param orig_type  the original type
6885  */
6886 static type_t *automatic_type_conversion(type_t *orig_type)
6887 {
6888         type_t *type = skip_typeref(orig_type);
6889         if (is_type_array(type)) {
6890                 array_type_t *array_type   = &type->array;
6891                 type_t       *element_type = array_type->element_type;
6892                 unsigned      qualifiers   = array_type->base.qualifiers;
6893
6894                 return make_pointer_type(element_type, qualifiers);
6895         }
6896
6897         if (is_type_function(type)) {
6898                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6899         }
6900
6901         return orig_type;
6902 }
6903
6904 /**
6905  * reverts the automatic casts of array to pointer types and function
6906  * to function-pointer types as defined § 6.3.2.1
6907  */
6908 type_t *revert_automatic_type_conversion(const expression_t *expression)
6909 {
6910         switch (expression->kind) {
6911                 case EXPR_REFERENCE: {
6912                         entity_t *entity = expression->reference.entity;
6913                         if (is_declaration(entity)) {
6914                                 return entity->declaration.type;
6915                         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6916                                 return entity->enum_value.enum_type;
6917                         } else {
6918                                 panic("no declaration or enum in reference");
6919                         }
6920                 }
6921
6922                 case EXPR_SELECT: {
6923                         entity_t *entity = expression->select.compound_entry;
6924                         assert(is_declaration(entity));
6925                         type_t   *type   = entity->declaration.type;
6926                         return get_qualified_type(type,
6927                                                   expression->base.type->base.qualifiers);
6928                 }
6929
6930                 case EXPR_UNARY_DEREFERENCE: {
6931                         const expression_t *const value = expression->unary.value;
6932                         type_t             *const type  = skip_typeref(value->base.type);
6933                         assert(is_type_pointer(type));
6934                         return type->pointer.points_to;
6935                 }
6936
6937                 case EXPR_BUILTIN_SYMBOL:
6938                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
6939
6940                 case EXPR_ARRAY_ACCESS: {
6941                         const expression_t *array_ref = expression->array_access.array_ref;
6942                         type_t             *type_left = skip_typeref(array_ref->base.type);
6943                         if (!is_type_valid(type_left))
6944                                 return type_left;
6945                         assert(is_type_pointer(type_left));
6946                         return type_left->pointer.points_to;
6947                 }
6948
6949                 case EXPR_STRING_LITERAL: {
6950                         size_t size = expression->string.value.size;
6951                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
6952                 }
6953
6954                 case EXPR_WIDE_STRING_LITERAL: {
6955                         size_t size = expression->wide_string.value.size;
6956                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
6957                 }
6958
6959                 case EXPR_COMPOUND_LITERAL:
6960                         return expression->compound_literal.type;
6961
6962                 default: break;
6963         }
6964
6965         return expression->base.type;
6966 }
6967
6968 static expression_t *parse_reference(void)
6969 {
6970         symbol_t *const symbol = token.v.symbol;
6971
6972         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
6973
6974         if (entity == NULL) {
6975                 if (!strict_mode && look_ahead(1)->type == '(') {
6976                         /* an implicitly declared function */
6977                         if (warning.error_implicit_function_declaration) {
6978                                 errorf(HERE, "implicit declaration of function '%Y'", symbol);
6979                         } else if (warning.implicit_function_declaration) {
6980                                 warningf(HERE, "implicit declaration of function '%Y'", symbol);
6981                         }
6982
6983                         entity = create_implicit_function(symbol, HERE);
6984                 } else {
6985                         errorf(HERE, "unknown identifier '%Y' found.", symbol);
6986                         entity = create_error_entity(symbol, ENTITY_VARIABLE);
6987                 }
6988         }
6989
6990         type_t *orig_type;
6991
6992         if (is_declaration(entity)) {
6993                 orig_type = entity->declaration.type;
6994         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6995                 orig_type = entity->enum_value.enum_type;
6996         } else if (entity->kind == ENTITY_TYPEDEF) {
6997                 errorf(HERE, "encountered typedef name '%Y' while parsing expression",
6998                         symbol);
6999                 next_token();
7000                 return create_invalid_expression();
7001         } else {
7002                 panic("expected declaration or enum value in reference");
7003         }
7004
7005         /* we always do the auto-type conversions; the & and sizeof parser contains
7006          * code to revert this! */
7007         type_t *type = automatic_type_conversion(orig_type);
7008
7009         expression_kind_t kind = EXPR_REFERENCE;
7010         if (entity->kind == ENTITY_ENUM_VALUE)
7011                 kind = EXPR_REFERENCE_ENUM_VALUE;
7012
7013         expression_t *expression     = allocate_expression_zero(kind);
7014         expression->reference.entity = entity;
7015         expression->base.type        = type;
7016
7017         /* this declaration is used */
7018         if (is_declaration(entity)) {
7019                 entity->declaration.used = true;
7020         }
7021
7022         if (entity->base.parent_scope != file_scope
7023                 && entity->base.parent_scope->depth < current_function->parameters.depth
7024                 && is_type_valid(orig_type) && !is_type_function(orig_type)) {
7025                 if (entity->kind == ENTITY_VARIABLE) {
7026                         /* access of a variable from an outer function */
7027                         entity->variable.address_taken = true;
7028                 } else if (entity->kind == ENTITY_PARAMETER) {
7029                         entity->parameter.address_taken = true;
7030                 }
7031                 current_function->need_closure = true;
7032         }
7033
7034         /* check for deprecated functions */
7035         if (warning.deprecated_declarations
7036                 && is_declaration(entity)
7037                 && entity->declaration.modifiers & DM_DEPRECATED) {
7038                 declaration_t *declaration = &entity->declaration;
7039
7040                 char const *const prefix = entity->kind == ENTITY_FUNCTION ?
7041                         "function" : "variable";
7042
7043                 if (declaration->deprecated_string != NULL) {
7044                         warningf(HERE, "%s '%Y' is deprecated (declared %P): \"%s\"",
7045                                  prefix, entity->base.symbol, &entity->base.source_position,
7046                                  declaration->deprecated_string);
7047                 } else {
7048                         warningf(HERE, "%s '%Y' is deprecated (declared %P)", prefix,
7049                                  entity->base.symbol, &entity->base.source_position);
7050                 }
7051         }
7052
7053         if (warning.init_self && entity == current_init_decl && !in_type_prop
7054             && entity->kind == ENTITY_VARIABLE) {
7055                 current_init_decl = NULL;
7056                 warningf(HERE, "variable '%#T' is initialized by itself",
7057                          entity->declaration.type, entity->base.symbol);
7058         }
7059
7060         next_token();
7061         return expression;
7062 }
7063
7064 static bool semantic_cast(expression_t *cast)
7065 {
7066         expression_t            *expression      = cast->unary.value;
7067         type_t                  *orig_dest_type  = cast->base.type;
7068         type_t                  *orig_type_right = expression->base.type;
7069         type_t            const *dst_type        = skip_typeref(orig_dest_type);
7070         type_t            const *src_type        = skip_typeref(orig_type_right);
7071         source_position_t const *pos             = &cast->base.source_position;
7072
7073         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
7074         if (dst_type == type_void)
7075                 return true;
7076
7077         /* only integer and pointer can be casted to pointer */
7078         if (is_type_pointer(dst_type)  &&
7079             !is_type_pointer(src_type) &&
7080             !is_type_integer(src_type) &&
7081             is_type_valid(src_type)) {
7082                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
7083                 return false;
7084         }
7085
7086         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
7087                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
7088                 return false;
7089         }
7090
7091         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
7092                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
7093                 return false;
7094         }
7095
7096         if (warning.cast_qual &&
7097             is_type_pointer(src_type) &&
7098             is_type_pointer(dst_type)) {
7099                 type_t *src = skip_typeref(src_type->pointer.points_to);
7100                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
7101                 unsigned missing_qualifiers =
7102                         src->base.qualifiers & ~dst->base.qualifiers;
7103                 if (missing_qualifiers != 0) {
7104                         warningf(pos,
7105                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
7106                                  missing_qualifiers, orig_type_right);
7107                 }
7108         }
7109         return true;
7110 }
7111
7112 static expression_t *parse_compound_literal(type_t *type)
7113 {
7114         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
7115
7116         parse_initializer_env_t env;
7117         env.type             = type;
7118         env.entity           = NULL;
7119         env.must_be_constant = false;
7120         initializer_t *initializer = parse_initializer(&env);
7121         type = env.type;
7122
7123         expression->compound_literal.initializer = initializer;
7124         expression->compound_literal.type        = type;
7125         expression->base.type                    = automatic_type_conversion(type);
7126
7127         return expression;
7128 }
7129
7130 /**
7131  * Parse a cast expression.
7132  */
7133 static expression_t *parse_cast(void)
7134 {
7135         add_anchor_token(')');
7136
7137         source_position_t source_position = token.source_position;
7138
7139         type_t *type = parse_typename();
7140
7141         rem_anchor_token(')');
7142         expect(')', end_error);
7143
7144         if (token.type == '{') {
7145                 return parse_compound_literal(type);
7146         }
7147
7148         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
7149         cast->base.source_position = source_position;
7150
7151         expression_t *value = parse_sub_expression(PREC_CAST);
7152         cast->base.type   = type;
7153         cast->unary.value = value;
7154
7155         if (! semantic_cast(cast)) {
7156                 /* TODO: record the error in the AST. else it is impossible to detect it */
7157         }
7158
7159         return cast;
7160 end_error:
7161         return create_invalid_expression();
7162 }
7163
7164 /**
7165  * Parse a statement expression.
7166  */
7167 static expression_t *parse_statement_expression(void)
7168 {
7169         add_anchor_token(')');
7170
7171         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
7172
7173         statement_t *statement          = parse_compound_statement(true);
7174         expression->statement.statement = statement;
7175
7176         /* find last statement and use its type */
7177         type_t *type = type_void;
7178         const statement_t *stmt = statement->compound.statements;
7179         if (stmt != NULL) {
7180                 while (stmt->base.next != NULL)
7181                         stmt = stmt->base.next;
7182
7183                 if (stmt->kind == STATEMENT_EXPRESSION) {
7184                         type = stmt->expression.expression->base.type;
7185                 }
7186         } else if (warning.other) {
7187                 warningf(&expression->base.source_position, "empty statement expression ({})");
7188         }
7189         expression->base.type = type;
7190
7191         rem_anchor_token(')');
7192         expect(')', end_error);
7193
7194 end_error:
7195         return expression;
7196 }
7197
7198 /**
7199  * Parse a parenthesized expression.
7200  */
7201 static expression_t *parse_parenthesized_expression(void)
7202 {
7203         eat('(');
7204
7205         switch (token.type) {
7206         case '{':
7207                 /* gcc extension: a statement expression */
7208                 return parse_statement_expression();
7209
7210         TYPE_QUALIFIERS
7211         TYPE_SPECIFIERS
7212                 return parse_cast();
7213         case T_IDENTIFIER:
7214                 if (is_typedef_symbol(token.v.symbol)) {
7215                         return parse_cast();
7216                 }
7217         }
7218
7219         add_anchor_token(')');
7220         expression_t *result = parse_expression();
7221         rem_anchor_token(')');
7222         expect(')', end_error);
7223
7224 end_error:
7225         return result;
7226 }
7227
7228 static expression_t *parse_function_keyword(void)
7229 {
7230         /* TODO */
7231
7232         if (current_function == NULL) {
7233                 errorf(HERE, "'__func__' used outside of a function");
7234         }
7235
7236         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7237         expression->base.type     = type_char_ptr;
7238         expression->funcname.kind = FUNCNAME_FUNCTION;
7239
7240         next_token();
7241
7242         return expression;
7243 }
7244
7245 static expression_t *parse_pretty_function_keyword(void)
7246 {
7247         if (current_function == NULL) {
7248                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
7249         }
7250
7251         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7252         expression->base.type     = type_char_ptr;
7253         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
7254
7255         eat(T___PRETTY_FUNCTION__);
7256
7257         return expression;
7258 }
7259
7260 static expression_t *parse_funcsig_keyword(void)
7261 {
7262         if (current_function == NULL) {
7263                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
7264         }
7265
7266         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7267         expression->base.type     = type_char_ptr;
7268         expression->funcname.kind = FUNCNAME_FUNCSIG;
7269
7270         eat(T___FUNCSIG__);
7271
7272         return expression;
7273 }
7274
7275 static expression_t *parse_funcdname_keyword(void)
7276 {
7277         if (current_function == NULL) {
7278                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
7279         }
7280
7281         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
7282         expression->base.type     = type_char_ptr;
7283         expression->funcname.kind = FUNCNAME_FUNCDNAME;
7284
7285         eat(T___FUNCDNAME__);
7286
7287         return expression;
7288 }
7289
7290 static designator_t *parse_designator(void)
7291 {
7292         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
7293         result->source_position = *HERE;
7294
7295         if (token.type != T_IDENTIFIER) {
7296                 parse_error_expected("while parsing member designator",
7297                                      T_IDENTIFIER, NULL);
7298                 return NULL;
7299         }
7300         result->symbol = token.v.symbol;
7301         next_token();
7302
7303         designator_t *last_designator = result;
7304         while (true) {
7305                 if (token.type == '.') {
7306                         next_token();
7307                         if (token.type != T_IDENTIFIER) {
7308                                 parse_error_expected("while parsing member designator",
7309                                                      T_IDENTIFIER, NULL);
7310                                 return NULL;
7311                         }
7312                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7313                         designator->source_position = *HERE;
7314                         designator->symbol          = token.v.symbol;
7315                         next_token();
7316
7317                         last_designator->next = designator;
7318                         last_designator       = designator;
7319                         continue;
7320                 }
7321                 if (token.type == '[') {
7322                         next_token();
7323                         add_anchor_token(']');
7324                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
7325                         designator->source_position = *HERE;
7326                         designator->array_index     = parse_expression();
7327                         rem_anchor_token(']');
7328                         expect(']', end_error);
7329                         if (designator->array_index == NULL) {
7330                                 return NULL;
7331                         }
7332
7333                         last_designator->next = designator;
7334                         last_designator       = designator;
7335                         continue;
7336                 }
7337                 break;
7338         }
7339
7340         return result;
7341 end_error:
7342         return NULL;
7343 }
7344
7345 /**
7346  * Parse the __builtin_offsetof() expression.
7347  */
7348 static expression_t *parse_offsetof(void)
7349 {
7350         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
7351         expression->base.type    = type_size_t;
7352
7353         eat(T___builtin_offsetof);
7354
7355         expect('(', end_error);
7356         add_anchor_token(',');
7357         type_t *type = parse_typename();
7358         rem_anchor_token(',');
7359         expect(',', end_error);
7360         add_anchor_token(')');
7361         designator_t *designator = parse_designator();
7362         rem_anchor_token(')');
7363         expect(')', end_error);
7364
7365         expression->offsetofe.type       = type;
7366         expression->offsetofe.designator = designator;
7367
7368         type_path_t path;
7369         memset(&path, 0, sizeof(path));
7370         path.top_type = type;
7371         path.path     = NEW_ARR_F(type_path_entry_t, 0);
7372
7373         descend_into_subtype(&path);
7374
7375         if (!walk_designator(&path, designator, true)) {
7376                 return create_invalid_expression();
7377         }
7378
7379         DEL_ARR_F(path.path);
7380
7381         return expression;
7382 end_error:
7383         return create_invalid_expression();
7384 }
7385
7386 /**
7387  * Parses a _builtin_va_start() expression.
7388  */
7389 static expression_t *parse_va_start(void)
7390 {
7391         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
7392
7393         eat(T___builtin_va_start);
7394
7395         expect('(', end_error);
7396         add_anchor_token(',');
7397         expression->va_starte.ap = parse_assignment_expression();
7398         rem_anchor_token(',');
7399         expect(',', end_error);
7400         expression_t *const expr = parse_assignment_expression();
7401         if (expr->kind == EXPR_REFERENCE) {
7402                 entity_t *const entity = expr->reference.entity;
7403                 if (entity->base.parent_scope != &current_function->parameters
7404                                 || entity->base.next != NULL
7405                                 || entity->kind != ENTITY_PARAMETER) {
7406                         errorf(&expr->base.source_position,
7407                                "second argument of 'va_start' must be last parameter of the current function");
7408                 } else {
7409                         expression->va_starte.parameter = &entity->variable;
7410                 }
7411                 expect(')', end_error);
7412                 return expression;
7413         }
7414         expect(')', end_error);
7415 end_error:
7416         return create_invalid_expression();
7417 }
7418
7419 /**
7420  * Parses a _builtin_va_arg() expression.
7421  */
7422 static expression_t *parse_va_arg(void)
7423 {
7424         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
7425
7426         eat(T___builtin_va_arg);
7427
7428         expect('(', end_error);
7429         expression->va_arge.ap = parse_assignment_expression();
7430         expect(',', end_error);
7431         expression->base.type = parse_typename();
7432         expect(')', end_error);
7433
7434         return expression;
7435 end_error:
7436         return create_invalid_expression();
7437 }
7438
7439 static expression_t *parse_builtin_symbol(void)
7440 {
7441         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
7442
7443         symbol_t *symbol = token.v.symbol;
7444
7445         expression->builtin_symbol.symbol = symbol;
7446         next_token();
7447
7448         type_t *type = get_builtin_symbol_type(symbol);
7449         type = automatic_type_conversion(type);
7450
7451         expression->base.type = type;
7452         return expression;
7453 }
7454
7455 /**
7456  * Parses a __builtin_constant() expression.
7457  */
7458 static expression_t *parse_builtin_constant(void)
7459 {
7460         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
7461
7462         eat(T___builtin_constant_p);
7463
7464         expect('(', end_error);
7465         add_anchor_token(')');
7466         expression->builtin_constant.value = parse_assignment_expression();
7467         rem_anchor_token(')');
7468         expect(')', end_error);
7469         expression->base.type = type_int;
7470
7471         return expression;
7472 end_error:
7473         return create_invalid_expression();
7474 }
7475
7476 /**
7477  * Parses a __builtin_prefetch() expression.
7478  */
7479 static expression_t *parse_builtin_prefetch(void)
7480 {
7481         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
7482
7483         eat(T___builtin_prefetch);
7484
7485         expect('(', end_error);
7486         add_anchor_token(')');
7487         expression->builtin_prefetch.adr = parse_assignment_expression();
7488         if (token.type == ',') {
7489                 next_token();
7490                 expression->builtin_prefetch.rw = parse_assignment_expression();
7491         }
7492         if (token.type == ',') {
7493                 next_token();
7494                 expression->builtin_prefetch.locality = parse_assignment_expression();
7495         }
7496         rem_anchor_token(')');
7497         expect(')', end_error);
7498         expression->base.type = type_void;
7499
7500         return expression;
7501 end_error:
7502         return create_invalid_expression();
7503 }
7504
7505 /**
7506  * Parses a __builtin_is_*() compare expression.
7507  */
7508 static expression_t *parse_compare_builtin(void)
7509 {
7510         expression_t *expression;
7511
7512         switch (token.type) {
7513         case T___builtin_isgreater:
7514                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
7515                 break;
7516         case T___builtin_isgreaterequal:
7517                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
7518                 break;
7519         case T___builtin_isless:
7520                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
7521                 break;
7522         case T___builtin_islessequal:
7523                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
7524                 break;
7525         case T___builtin_islessgreater:
7526                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
7527                 break;
7528         case T___builtin_isunordered:
7529                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
7530                 break;
7531         default:
7532                 internal_errorf(HERE, "invalid compare builtin found");
7533         }
7534         expression->base.source_position = *HERE;
7535         next_token();
7536
7537         expect('(', end_error);
7538         expression->binary.left = parse_assignment_expression();
7539         expect(',', end_error);
7540         expression->binary.right = parse_assignment_expression();
7541         expect(')', end_error);
7542
7543         type_t *const orig_type_left  = expression->binary.left->base.type;
7544         type_t *const orig_type_right = expression->binary.right->base.type;
7545
7546         type_t *const type_left  = skip_typeref(orig_type_left);
7547         type_t *const type_right = skip_typeref(orig_type_right);
7548         if (!is_type_float(type_left) && !is_type_float(type_right)) {
7549                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7550                         type_error_incompatible("invalid operands in comparison",
7551                                 &expression->base.source_position, orig_type_left, orig_type_right);
7552                 }
7553         } else {
7554                 semantic_comparison(&expression->binary);
7555         }
7556
7557         return expression;
7558 end_error:
7559         return create_invalid_expression();
7560 }
7561
7562 #if 0
7563 /**
7564  * Parses a __builtin_expect(, end_error) expression.
7565  */
7566 static expression_t *parse_builtin_expect(void, end_error)
7567 {
7568         expression_t *expression
7569                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
7570
7571         eat(T___builtin_expect);
7572
7573         expect('(', end_error);
7574         expression->binary.left = parse_assignment_expression();
7575         expect(',', end_error);
7576         expression->binary.right = parse_constant_expression();
7577         expect(')', end_error);
7578
7579         expression->base.type = expression->binary.left->base.type;
7580
7581         return expression;
7582 end_error:
7583         return create_invalid_expression();
7584 }
7585 #endif
7586
7587 /**
7588  * Parses a MS assume() expression.
7589  */
7590 static expression_t *parse_assume(void)
7591 {
7592         expression_t *expression = allocate_expression_zero(EXPR_UNARY_ASSUME);
7593
7594         eat(T__assume);
7595
7596         expect('(', end_error);
7597         add_anchor_token(')');
7598         expression->unary.value = parse_assignment_expression();
7599         rem_anchor_token(')');
7600         expect(')', end_error);
7601
7602         expression->base.type = type_void;
7603         return expression;
7604 end_error:
7605         return create_invalid_expression();
7606 }
7607
7608 /**
7609  * Return the declaration for a given label symbol or create a new one.
7610  *
7611  * @param symbol  the symbol of the label
7612  */
7613 static label_t *get_label(symbol_t *symbol)
7614 {
7615         entity_t *label;
7616         assert(current_function != NULL);
7617
7618         label = get_entity(symbol, NAMESPACE_LABEL);
7619         /* if we found a local label, we already created the declaration */
7620         if (label != NULL && label->kind == ENTITY_LOCAL_LABEL) {
7621                 if (label->base.parent_scope != current_scope) {
7622                         assert(label->base.parent_scope->depth < current_scope->depth);
7623                         current_function->goto_to_outer = true;
7624                 }
7625                 return &label->label;
7626         }
7627
7628         label = get_entity(symbol, NAMESPACE_LABEL);
7629         /* if we found a label in the same function, then we already created the
7630          * declaration */
7631         if (label != NULL
7632                         && label->base.parent_scope == &current_function->parameters) {
7633                 return &label->label;
7634         }
7635
7636         /* otherwise we need to create a new one */
7637         label               = allocate_entity_zero(ENTITY_LABEL);
7638         label->base.namespc = NAMESPACE_LABEL;
7639         label->base.symbol  = symbol;
7640
7641         label_push(label);
7642
7643         return &label->label;
7644 }
7645
7646 /**
7647  * Parses a GNU && label address expression.
7648  */
7649 static expression_t *parse_label_address(void)
7650 {
7651         source_position_t source_position = token.source_position;
7652         eat(T_ANDAND);
7653         if (token.type != T_IDENTIFIER) {
7654                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
7655                 goto end_error;
7656         }
7657         symbol_t *symbol = token.v.symbol;
7658         next_token();
7659
7660         label_t *label       = get_label(symbol);
7661         label->used          = true;
7662         label->address_taken = true;
7663
7664         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
7665         expression->base.source_position = source_position;
7666
7667         /* label address is threaten as a void pointer */
7668         expression->base.type           = type_void_ptr;
7669         expression->label_address.label = label;
7670         return expression;
7671 end_error:
7672         return create_invalid_expression();
7673 }
7674
7675 /**
7676  * Parse a microsoft __noop expression.
7677  */
7678 static expression_t *parse_noop_expression(void)
7679 {
7680         /* the result is a (int)0 */
7681         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
7682         cnst->base.type            = type_int;
7683         cnst->conste.v.int_value   = 0;
7684         cnst->conste.is_ms_noop    = true;
7685
7686         eat(T___noop);
7687
7688         if (token.type == '(') {
7689                 /* parse arguments */
7690                 eat('(');
7691                 add_anchor_token(')');
7692                 add_anchor_token(',');
7693
7694                 if (token.type != ')') {
7695                         while (true) {
7696                                 (void)parse_assignment_expression();
7697                                 if (token.type != ',')
7698                                         break;
7699                                 next_token();
7700                         }
7701                 }
7702         }
7703         rem_anchor_token(',');
7704         rem_anchor_token(')');
7705         expect(')', end_error);
7706
7707 end_error:
7708         return cnst;
7709 }
7710
7711 /**
7712  * Parses a primary expression.
7713  */
7714 static expression_t *parse_primary_expression(void)
7715 {
7716         switch (token.type) {
7717                 case T_false:                    return parse_bool_const(false);
7718                 case T_true:                     return parse_bool_const(true);
7719                 case T_INTEGER:                  return parse_int_const();
7720                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
7721                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
7722                 case T_FLOATINGPOINT:            return parse_float_const();
7723                 case T_STRING_LITERAL:
7724                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
7725                 case T_IDENTIFIER:               return parse_reference();
7726                 case T___FUNCTION__:
7727                 case T___func__:                 return parse_function_keyword();
7728                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
7729                 case T___FUNCSIG__:              return parse_funcsig_keyword();
7730                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
7731                 case T___builtin_offsetof:       return parse_offsetof();
7732                 case T___builtin_va_start:       return parse_va_start();
7733                 case T___builtin_va_arg:         return parse_va_arg();
7734                 case T___builtin_expect:
7735                 case T___builtin_alloca:
7736                 case T___builtin_inf:
7737                 case T___builtin_inff:
7738                 case T___builtin_infl:
7739                 case T___builtin_nan:
7740                 case T___builtin_nanf:
7741                 case T___builtin_nanl:
7742                 case T___builtin_huge_val:
7743                 case T___builtin_va_end:         return parse_builtin_symbol();
7744                 case T___builtin_isgreater:
7745                 case T___builtin_isgreaterequal:
7746                 case T___builtin_isless:
7747                 case T___builtin_islessequal:
7748                 case T___builtin_islessgreater:
7749                 case T___builtin_isunordered:    return parse_compare_builtin();
7750                 case T___builtin_constant_p:     return parse_builtin_constant();
7751                 case T___builtin_prefetch:       return parse_builtin_prefetch();
7752                 case T__assume:                  return parse_assume();
7753                 case T_ANDAND:
7754                         if (GNU_MODE)
7755                                 return parse_label_address();
7756                         break;
7757
7758                 case '(':                        return parse_parenthesized_expression();
7759                 case T___noop:                   return parse_noop_expression();
7760         }
7761
7762         errorf(HERE, "unexpected token %K, expected an expression", &token);
7763         return create_invalid_expression();
7764 }
7765
7766 /**
7767  * Check if the expression has the character type and issue a warning then.
7768  */
7769 static void check_for_char_index_type(const expression_t *expression)
7770 {
7771         type_t       *const type      = expression->base.type;
7772         const type_t *const base_type = skip_typeref(type);
7773
7774         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
7775                         warning.char_subscripts) {
7776                 warningf(&expression->base.source_position,
7777                          "array subscript has type '%T'", type);
7778         }
7779 }
7780
7781 static expression_t *parse_array_expression(expression_t *left)
7782 {
7783         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
7784
7785         eat('[');
7786         add_anchor_token(']');
7787
7788         expression_t *inside = parse_expression();
7789
7790         type_t *const orig_type_left   = left->base.type;
7791         type_t *const orig_type_inside = inside->base.type;
7792
7793         type_t *const type_left   = skip_typeref(orig_type_left);
7794         type_t *const type_inside = skip_typeref(orig_type_inside);
7795
7796         type_t                    *return_type;
7797         array_access_expression_t *array_access = &expression->array_access;
7798         if (is_type_pointer(type_left)) {
7799                 return_type             = type_left->pointer.points_to;
7800                 array_access->array_ref = left;
7801                 array_access->index     = inside;
7802                 check_for_char_index_type(inside);
7803         } else if (is_type_pointer(type_inside)) {
7804                 return_type             = type_inside->pointer.points_to;
7805                 array_access->array_ref = inside;
7806                 array_access->index     = left;
7807                 array_access->flipped   = true;
7808                 check_for_char_index_type(left);
7809         } else {
7810                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
7811                         errorf(HERE,
7812                                 "array access on object with non-pointer types '%T', '%T'",
7813                                 orig_type_left, orig_type_inside);
7814                 }
7815                 return_type             = type_error_type;
7816                 array_access->array_ref = left;
7817                 array_access->index     = inside;
7818         }
7819
7820         expression->base.type = automatic_type_conversion(return_type);
7821
7822         rem_anchor_token(']');
7823         expect(']', end_error);
7824 end_error:
7825         return expression;
7826 }
7827
7828 static expression_t *parse_typeprop(expression_kind_t const kind)
7829 {
7830         expression_t  *tp_expression = allocate_expression_zero(kind);
7831         tp_expression->base.type     = type_size_t;
7832
7833         eat(kind == EXPR_SIZEOF ? T_sizeof : T___alignof__);
7834
7835         /* we only refer to a type property, mark this case */
7836         bool old     = in_type_prop;
7837         in_type_prop = true;
7838
7839         type_t       *orig_type;
7840         expression_t *expression;
7841         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
7842                 next_token();
7843                 add_anchor_token(')');
7844                 orig_type = parse_typename();
7845                 rem_anchor_token(')');
7846                 expect(')', end_error);
7847
7848                 if (token.type == '{') {
7849                         /* It was not sizeof(type) after all.  It is sizeof of an expression
7850                          * starting with a compound literal */
7851                         expression = parse_compound_literal(orig_type);
7852                         goto typeprop_expression;
7853                 }
7854         } else {
7855                 expression = parse_sub_expression(PREC_UNARY);
7856
7857 typeprop_expression:
7858                 tp_expression->typeprop.tp_expression = expression;
7859
7860                 orig_type = revert_automatic_type_conversion(expression);
7861                 expression->base.type = orig_type;
7862         }
7863
7864         tp_expression->typeprop.type   = orig_type;
7865         type_t const* const type       = skip_typeref(orig_type);
7866         char   const* const wrong_type =
7867                 is_type_incomplete(type)    ? "incomplete"          :
7868                 type->kind == TYPE_FUNCTION ? "function designator" :
7869                 type->kind == TYPE_BITFIELD ? "bitfield"            :
7870                 NULL;
7871         if (wrong_type != NULL) {
7872                 char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7873                 errorf(&tp_expression->base.source_position,
7874                                 "operand of %s expression must not be of %s type '%T'",
7875                                 what, wrong_type, orig_type);
7876         }
7877
7878 end_error:
7879         in_type_prop = old;
7880         return tp_expression;
7881 }
7882
7883 static expression_t *parse_sizeof(void)
7884 {
7885         return parse_typeprop(EXPR_SIZEOF);
7886 }
7887
7888 static expression_t *parse_alignof(void)
7889 {
7890         return parse_typeprop(EXPR_ALIGNOF);
7891 }
7892
7893 static expression_t *parse_select_expression(expression_t *compound)
7894 {
7895         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
7896         select->select.compound = compound;
7897
7898         assert(token.type == '.' || token.type == T_MINUSGREATER);
7899         bool is_pointer = (token.type == T_MINUSGREATER);
7900         next_token();
7901
7902         if (token.type != T_IDENTIFIER) {
7903                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
7904                 return select;
7905         }
7906         symbol_t *symbol = token.v.symbol;
7907         next_token();
7908
7909         type_t *const orig_type = compound->base.type;
7910         type_t *const type      = skip_typeref(orig_type);
7911
7912         type_t *type_left;
7913         bool    saw_error = false;
7914         if (is_type_pointer(type)) {
7915                 if (!is_pointer) {
7916                         errorf(HERE,
7917                                "request for member '%Y' in something not a struct or union, but '%T'",
7918                                symbol, orig_type);
7919                         saw_error = true;
7920                 }
7921                 type_left = skip_typeref(type->pointer.points_to);
7922         } else {
7923                 if (is_pointer && is_type_valid(type)) {
7924                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7925                         saw_error = true;
7926                 }
7927                 type_left = type;
7928         }
7929
7930         entity_t *entry;
7931         if (type_left->kind == TYPE_COMPOUND_STRUCT ||
7932             type_left->kind == TYPE_COMPOUND_UNION) {
7933                 compound_t *compound = type_left->compound.compound;
7934
7935                 if (!compound->complete) {
7936                         errorf(HERE, "request for member '%Y' of incomplete type '%T'",
7937                                symbol, type_left);
7938                         goto create_error_entry;
7939                 }
7940
7941                 entry = find_compound_entry(compound, symbol);
7942                 if (entry == NULL) {
7943                         errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
7944                         goto create_error_entry;
7945                 }
7946         } else {
7947                 if (is_type_valid(type_left) && !saw_error) {
7948                         errorf(HERE,
7949                                "request for member '%Y' in something not a struct or union, but '%T'",
7950                                symbol, type_left);
7951                 }
7952 create_error_entry:
7953                 entry = create_error_entity(symbol, ENTITY_COMPOUND_MEMBER);
7954         }
7955
7956         assert(is_declaration(entry));
7957         select->select.compound_entry = entry;
7958
7959         type_t *entry_type = entry->declaration.type;
7960         type_t *res_type
7961                 = get_qualified_type(entry_type, type_left->base.qualifiers);
7962
7963         /* we always do the auto-type conversions; the & and sizeof parser contains
7964          * code to revert this! */
7965         select->base.type = automatic_type_conversion(res_type);
7966
7967         type_t *skipped = skip_typeref(res_type);
7968         if (skipped->kind == TYPE_BITFIELD) {
7969                 select->base.type = skipped->bitfield.base_type;
7970         }
7971
7972         return select;
7973 }
7974
7975 static void check_call_argument(const function_parameter_t *parameter,
7976                                 call_argument_t *argument, unsigned pos)
7977 {
7978         type_t         *expected_type      = parameter->type;
7979         type_t         *expected_type_skip = skip_typeref(expected_type);
7980         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
7981         expression_t   *arg_expr           = argument->expression;
7982         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
7983
7984         /* handle transparent union gnu extension */
7985         if (is_type_union(expected_type_skip)
7986                         && (expected_type_skip->base.modifiers
7987                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
7988                 compound_t *union_decl  = expected_type_skip->compound.compound;
7989                 type_t     *best_type   = NULL;
7990                 entity_t   *entry       = union_decl->members.entities;
7991                 for ( ; entry != NULL; entry = entry->base.next) {
7992                         assert(is_declaration(entry));
7993                         type_t *decl_type = entry->declaration.type;
7994                         error = semantic_assign(decl_type, arg_expr);
7995                         if (error == ASSIGN_ERROR_INCOMPATIBLE
7996                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
7997                                 continue;
7998
7999                         if (error == ASSIGN_SUCCESS) {
8000                                 best_type = decl_type;
8001                         } else if (best_type == NULL) {
8002                                 best_type = decl_type;
8003                         }
8004                 }
8005
8006                 if (best_type != NULL) {
8007                         expected_type = best_type;
8008                 }
8009         }
8010
8011         error                = semantic_assign(expected_type, arg_expr);
8012         argument->expression = create_implicit_cast(argument->expression,
8013                                                     expected_type);
8014
8015         if (error != ASSIGN_SUCCESS) {
8016                 /* report exact scope in error messages (like "in argument 3") */
8017                 char buf[64];
8018                 snprintf(buf, sizeof(buf), "call argument %u", pos);
8019                 report_assign_error(error, expected_type, arg_expr,     buf,
8020                                                         &arg_expr->base.source_position);
8021         } else if (warning.traditional || warning.conversion) {
8022                 type_t *const promoted_type = get_default_promoted_type(arg_type);
8023                 if (!types_compatible(expected_type_skip, promoted_type) &&
8024                     !types_compatible(expected_type_skip, type_void_ptr) &&
8025                     !types_compatible(type_void_ptr,      promoted_type)) {
8026                         /* Deliberately show the skipped types in this warning */
8027                         warningf(&arg_expr->base.source_position,
8028                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
8029                                 pos, expected_type_skip, promoted_type);
8030                 }
8031         }
8032 }
8033
8034 /**
8035  * Parse a call expression, ie. expression '( ... )'.
8036  *
8037  * @param expression  the function address
8038  */
8039 static expression_t *parse_call_expression(expression_t *expression)
8040 {
8041         expression_t      *result = allocate_expression_zero(EXPR_CALL);
8042         call_expression_t *call   = &result->call;
8043         call->function            = expression;
8044
8045         type_t *const orig_type = expression->base.type;
8046         type_t *const type      = skip_typeref(orig_type);
8047
8048         function_type_t *function_type = NULL;
8049         if (is_type_pointer(type)) {
8050                 type_t *const to_type = skip_typeref(type->pointer.points_to);
8051
8052                 if (is_type_function(to_type)) {
8053                         function_type   = &to_type->function;
8054                         call->base.type = function_type->return_type;
8055                 }
8056         }
8057
8058         if (function_type == NULL && is_type_valid(type)) {
8059                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
8060         }
8061
8062         /* parse arguments */
8063         eat('(');
8064         add_anchor_token(')');
8065         add_anchor_token(',');
8066
8067         if (token.type != ')') {
8068                 call_argument_t *last_argument = NULL;
8069
8070                 while (true) {
8071                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
8072
8073                         argument->expression = parse_assignment_expression();
8074                         if (last_argument == NULL) {
8075                                 call->arguments = argument;
8076                         } else {
8077                                 last_argument->next = argument;
8078                         }
8079                         last_argument = argument;
8080
8081                         if (token.type != ',')
8082                                 break;
8083                         next_token();
8084                 }
8085         }
8086         rem_anchor_token(',');
8087         rem_anchor_token(')');
8088         expect(')', end_error);
8089
8090         if (function_type == NULL)
8091                 return result;
8092
8093         function_parameter_t *parameter = function_type->parameters;
8094         call_argument_t      *argument  = call->arguments;
8095         if (!function_type->unspecified_parameters) {
8096                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
8097                                 parameter = parameter->next, argument = argument->next) {
8098                         check_call_argument(parameter, argument, ++pos);
8099                 }
8100
8101                 if (parameter != NULL) {
8102                         errorf(HERE, "too few arguments to function '%E'", expression);
8103                 } else if (argument != NULL && !function_type->variadic) {
8104                         errorf(HERE, "too many arguments to function '%E'", expression);
8105                 }
8106         }
8107
8108         /* do default promotion */
8109         for (; argument != NULL; argument = argument->next) {
8110                 type_t *type = argument->expression->base.type;
8111
8112                 type = get_default_promoted_type(type);
8113
8114                 argument->expression
8115                         = create_implicit_cast(argument->expression, type);
8116         }
8117
8118         check_format(&result->call);
8119
8120         if (warning.aggregate_return &&
8121             is_type_compound(skip_typeref(function_type->return_type))) {
8122                 warningf(&result->base.source_position,
8123                          "function call has aggregate value");
8124         }
8125
8126 end_error:
8127         return result;
8128 }
8129
8130 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
8131
8132 static bool same_compound_type(const type_t *type1, const type_t *type2)
8133 {
8134         return
8135                 is_type_compound(type1) &&
8136                 type1->kind == type2->kind &&
8137                 type1->compound.compound == type2->compound.compound;
8138 }
8139
8140 static expression_t const *get_reference_address(expression_t const *expr)
8141 {
8142         bool regular_take_address = true;
8143         for (;;) {
8144                 if (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8145                         expr = expr->unary.value;
8146                 } else {
8147                         regular_take_address = false;
8148                 }
8149
8150                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8151                         break;
8152
8153                 expr = expr->unary.value;
8154         }
8155
8156         if (expr->kind != EXPR_REFERENCE)
8157                 return NULL;
8158
8159         /* special case for functions which are automatically converted to a
8160          * pointer to function without an extra TAKE_ADDRESS operation */
8161         if (!regular_take_address &&
8162                         expr->reference.entity->kind != ENTITY_FUNCTION) {
8163                 return NULL;
8164         }
8165
8166         return expr;
8167 }
8168
8169 static void warn_reference_address_as_bool(expression_t const* expr)
8170 {
8171         if (!warning.address)
8172                 return;
8173
8174         expr = get_reference_address(expr);
8175         if (expr != NULL) {
8176                 warningf(&expr->base.source_position,
8177                          "the address of '%Y' will always evaluate as 'true'",
8178                          expr->reference.entity->base.symbol);
8179         }
8180 }
8181
8182 static void semantic_condition(expression_t const *const expr,
8183                                char const *const context)
8184 {
8185         type_t *const type = skip_typeref(expr->base.type);
8186         if (is_type_scalar(type)) {
8187                 warn_reference_address_as_bool(expr);
8188         } else if (is_type_valid(type)) {
8189                 errorf(&expr->base.source_position,
8190                                 "%s must have scalar type", context);
8191         }
8192 }
8193
8194 /**
8195  * Parse a conditional expression, ie. 'expression ? ... : ...'.
8196  *
8197  * @param expression  the conditional expression
8198  */
8199 static expression_t *parse_conditional_expression(expression_t *expression)
8200 {
8201         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
8202
8203         conditional_expression_t *conditional = &result->conditional;
8204         conditional->condition                = expression;
8205
8206         eat('?');
8207         add_anchor_token(':');
8208
8209         /* §6.5.15:2  The first operand shall have scalar type. */
8210         semantic_condition(expression, "condition of conditional operator");
8211
8212         expression_t *true_expression = expression;
8213         bool          gnu_cond = false;
8214         if (GNU_MODE && token.type == ':') {
8215                 gnu_cond = true;
8216         } else {
8217                 true_expression = parse_expression();
8218         }
8219         rem_anchor_token(':');
8220         expect(':', end_error);
8221         expression_t *false_expression =
8222                 parse_sub_expression(c_mode & _CXX ? PREC_ASSIGNMENT : PREC_CONDITIONAL);
8223
8224         type_t *const orig_true_type  = true_expression->base.type;
8225         type_t *const orig_false_type = false_expression->base.type;
8226         type_t *const true_type       = skip_typeref(orig_true_type);
8227         type_t *const false_type      = skip_typeref(orig_false_type);
8228
8229         /* 6.5.15.3 */
8230         type_t *result_type;
8231         if (is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8232                         is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
8233                 /* ISO/IEC 14882:1998(E) §5.16:2 */
8234                 if (true_expression->kind == EXPR_UNARY_THROW) {
8235                         result_type = false_type;
8236                 } else if (false_expression->kind == EXPR_UNARY_THROW) {
8237                         result_type = true_type;
8238                 } else {
8239                         if (warning.other && (
8240                                                 !is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
8241                                                 !is_type_atomic(false_type, ATOMIC_TYPE_VOID)
8242                                         )) {
8243                                 warningf(&conditional->base.source_position,
8244                                                 "ISO C forbids conditional expression with only one void side");
8245                         }
8246                         result_type = type_void;
8247                 }
8248         } else if (is_type_arithmetic(true_type)
8249                    && is_type_arithmetic(false_type)) {
8250                 result_type = semantic_arithmetic(true_type, false_type);
8251
8252                 true_expression  = create_implicit_cast(true_expression, result_type);
8253                 false_expression = create_implicit_cast(false_expression, result_type);
8254
8255                 conditional->true_expression  = true_expression;
8256                 conditional->false_expression = false_expression;
8257                 conditional->base.type        = result_type;
8258         } else if (same_compound_type(true_type, false_type)) {
8259                 /* just take 1 of the 2 types */
8260                 result_type = true_type;
8261         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
8262                 type_t *pointer_type;
8263                 type_t *other_type;
8264                 expression_t *other_expression;
8265                 if (is_type_pointer(true_type) &&
8266                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
8267                         pointer_type     = true_type;
8268                         other_type       = false_type;
8269                         other_expression = false_expression;
8270                 } else {
8271                         pointer_type     = false_type;
8272                         other_type       = true_type;
8273                         other_expression = true_expression;
8274                 }
8275
8276                 if (is_null_pointer_constant(other_expression)) {
8277                         result_type = pointer_type;
8278                 } else if (is_type_pointer(other_type)) {
8279                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
8280                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
8281
8282                         type_t *to;
8283                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
8284                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
8285                                 to = type_void;
8286                         } else if (types_compatible(get_unqualified_type(to1),
8287                                                     get_unqualified_type(to2))) {
8288                                 to = to1;
8289                         } else {
8290                                 if (warning.other) {
8291                                         warningf(&conditional->base.source_position,
8292                                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
8293                                                         true_type, false_type);
8294                                 }
8295                                 to = type_void;
8296                         }
8297
8298                         type_t *const type =
8299                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
8300                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
8301                 } else if (is_type_integer(other_type)) {
8302                         if (warning.other) {
8303                                 warningf(&conditional->base.source_position,
8304                                                 "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
8305                         }
8306                         result_type = pointer_type;
8307                 } else {
8308                         if (is_type_valid(other_type)) {
8309                                 type_error_incompatible("while parsing conditional",
8310                                                 &expression->base.source_position, true_type, false_type);
8311                         }
8312                         result_type = type_error_type;
8313                 }
8314         } else {
8315                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
8316                         type_error_incompatible("while parsing conditional",
8317                                                 &conditional->base.source_position, true_type,
8318                                                 false_type);
8319                 }
8320                 result_type = type_error_type;
8321         }
8322
8323         conditional->true_expression
8324                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
8325         conditional->false_expression
8326                 = create_implicit_cast(false_expression, result_type);
8327         conditional->base.type = result_type;
8328         return result;
8329 end_error:
8330         return create_invalid_expression();
8331 }
8332
8333 /**
8334  * Parse an extension expression.
8335  */
8336 static expression_t *parse_extension(void)
8337 {
8338         eat(T___extension__);
8339
8340         bool old_gcc_extension   = in_gcc_extension;
8341         in_gcc_extension         = true;
8342         expression_t *expression = parse_sub_expression(PREC_UNARY);
8343         in_gcc_extension         = old_gcc_extension;
8344         return expression;
8345 }
8346
8347 /**
8348  * Parse a __builtin_classify_type() expression.
8349  */
8350 static expression_t *parse_builtin_classify_type(void)
8351 {
8352         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
8353         result->base.type    = type_int;
8354
8355         eat(T___builtin_classify_type);
8356
8357         expect('(', end_error);
8358         add_anchor_token(')');
8359         expression_t *expression = parse_expression();
8360         rem_anchor_token(')');
8361         expect(')', end_error);
8362         result->classify_type.type_expression = expression;
8363
8364         return result;
8365 end_error:
8366         return create_invalid_expression();
8367 }
8368
8369 /**
8370  * Parse a delete expression
8371  * ISO/IEC 14882:1998(E) §5.3.5
8372  */
8373 static expression_t *parse_delete(void)
8374 {
8375         expression_t *const result = allocate_expression_zero(EXPR_UNARY_DELETE);
8376         result->base.type          = type_void;
8377
8378         eat(T_delete);
8379
8380         if (token.type == '[') {
8381                 next_token();
8382                 result->kind = EXPR_UNARY_DELETE_ARRAY;
8383                 expect(']', end_error);
8384 end_error:;
8385         }
8386
8387         expression_t *const value = parse_sub_expression(PREC_CAST);
8388         result->unary.value = value;
8389
8390         type_t *const type = skip_typeref(value->base.type);
8391         if (!is_type_pointer(type)) {
8392                 errorf(&value->base.source_position,
8393                                 "operand of delete must have pointer type");
8394         } else if (warning.other &&
8395                         is_type_atomic(skip_typeref(type->pointer.points_to), ATOMIC_TYPE_VOID)) {
8396                 warningf(&value->base.source_position,
8397                                 "deleting 'void*' is undefined");
8398         }
8399
8400         return result;
8401 }
8402
8403 /**
8404  * Parse a throw expression
8405  * ISO/IEC 14882:1998(E) §15:1
8406  */
8407 static expression_t *parse_throw(void)
8408 {
8409         expression_t *const result = allocate_expression_zero(EXPR_UNARY_THROW);
8410         result->base.type          = type_void;
8411
8412         eat(T_throw);
8413
8414         expression_t *value = NULL;
8415         switch (token.type) {
8416                 EXPRESSION_START {
8417                         value = parse_assignment_expression();
8418                         /* ISO/IEC 14882:1998(E) §15.1:3 */
8419                         type_t *const orig_type = value->base.type;
8420                         type_t *const type      = skip_typeref(orig_type);
8421                         if (is_type_incomplete(type)) {
8422                                 errorf(&value->base.source_position,
8423                                                 "cannot throw object of incomplete type '%T'", orig_type);
8424                         } else if (is_type_pointer(type)) {
8425                                 type_t *const points_to = skip_typeref(type->pointer.points_to);
8426                                 if (is_type_incomplete(points_to) &&
8427                                                 !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8428                                         errorf(&value->base.source_position,
8429                                                         "cannot throw pointer to incomplete type '%T'", orig_type);
8430                                 }
8431                         }
8432                 }
8433
8434                 default:
8435                         break;
8436         }
8437         result->unary.value = value;
8438
8439         return result;
8440 }
8441
8442 static bool check_pointer_arithmetic(const source_position_t *source_position,
8443                                      type_t *pointer_type,
8444                                      type_t *orig_pointer_type)
8445 {
8446         type_t *points_to = pointer_type->pointer.points_to;
8447         points_to = skip_typeref(points_to);
8448
8449         if (is_type_incomplete(points_to)) {
8450                 if (!GNU_MODE || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
8451                         errorf(source_position,
8452                                "arithmetic with pointer to incomplete type '%T' not allowed",
8453                                orig_pointer_type);
8454                         return false;
8455                 } else if (warning.pointer_arith) {
8456                         warningf(source_position,
8457                                  "pointer of type '%T' used in arithmetic",
8458                                  orig_pointer_type);
8459                 }
8460         } else if (is_type_function(points_to)) {
8461                 if (!GNU_MODE) {
8462                         errorf(source_position,
8463                                "arithmetic with pointer to function type '%T' not allowed",
8464                                orig_pointer_type);
8465                         return false;
8466                 } else if (warning.pointer_arith) {
8467                         warningf(source_position,
8468                                  "pointer to a function '%T' used in arithmetic",
8469                                  orig_pointer_type);
8470                 }
8471         }
8472         return true;
8473 }
8474
8475 static bool is_lvalue(const expression_t *expression)
8476 {
8477         /* TODO: doesn't seem to be consistent with §6.3.2.1 (1) */
8478         switch (expression->kind) {
8479         case EXPR_REFERENCE:
8480         case EXPR_ARRAY_ACCESS:
8481         case EXPR_SELECT:
8482         case EXPR_UNARY_DEREFERENCE:
8483                 return true;
8484
8485         default: {
8486           type_t *type = skip_typeref(expression->base.type);
8487           return
8488                 /* ISO/IEC 14882:1998(E) §3.10:3 */
8489                 is_type_reference(type) ||
8490                 /* Claim it is an lvalue, if the type is invalid.  There was a parse
8491                  * error before, which maybe prevented properly recognizing it as
8492                  * lvalue. */
8493                 !is_type_valid(type);
8494         }
8495         }
8496 }
8497
8498 static void semantic_incdec(unary_expression_t *expression)
8499 {
8500         type_t *const orig_type = expression->value->base.type;
8501         type_t *const type      = skip_typeref(orig_type);
8502         if (is_type_pointer(type)) {
8503                 if (!check_pointer_arithmetic(&expression->base.source_position,
8504                                               type, orig_type)) {
8505                         return;
8506                 }
8507         } else if (!is_type_real(type) && is_type_valid(type)) {
8508                 /* TODO: improve error message */
8509                 errorf(&expression->base.source_position,
8510                        "operation needs an arithmetic or pointer type");
8511                 return;
8512         }
8513         if (!is_lvalue(expression->value)) {
8514                 /* TODO: improve error message */
8515                 errorf(&expression->base.source_position, "lvalue required as operand");
8516         }
8517         expression->base.type = orig_type;
8518 }
8519
8520 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
8521 {
8522         type_t *const orig_type = expression->value->base.type;
8523         type_t *const type      = skip_typeref(orig_type);
8524         if (!is_type_arithmetic(type)) {
8525                 if (is_type_valid(type)) {
8526                         /* TODO: improve error message */
8527                         errorf(&expression->base.source_position,
8528                                 "operation needs an arithmetic type");
8529                 }
8530                 return;
8531         }
8532
8533         expression->base.type = orig_type;
8534 }
8535
8536 static void semantic_unexpr_plus(unary_expression_t *expression)
8537 {
8538         semantic_unexpr_arithmetic(expression);
8539         if (warning.traditional)
8540                 warningf(&expression->base.source_position,
8541                         "traditional C rejects the unary plus operator");
8542 }
8543
8544 static void semantic_not(unary_expression_t *expression)
8545 {
8546         /* §6.5.3.3:1  The operand [...] of the ! operator, scalar type. */
8547         semantic_condition(expression->value, "operand of !");
8548         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8549 }
8550
8551 static void semantic_unexpr_integer(unary_expression_t *expression)
8552 {
8553         type_t *const orig_type = expression->value->base.type;
8554         type_t *const type      = skip_typeref(orig_type);
8555         if (!is_type_integer(type)) {
8556                 if (is_type_valid(type)) {
8557                         errorf(&expression->base.source_position,
8558                                "operand of ~ must be of integer type");
8559                 }
8560                 return;
8561         }
8562
8563         expression->base.type = orig_type;
8564 }
8565
8566 static void semantic_dereference(unary_expression_t *expression)
8567 {
8568         type_t *const orig_type = expression->value->base.type;
8569         type_t *const type      = skip_typeref(orig_type);
8570         if (!is_type_pointer(type)) {
8571                 if (is_type_valid(type)) {
8572                         errorf(&expression->base.source_position,
8573                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
8574                 }
8575                 return;
8576         }
8577
8578         type_t *result_type   = type->pointer.points_to;
8579         result_type           = automatic_type_conversion(result_type);
8580         expression->base.type = result_type;
8581 }
8582
8583 /**
8584  * Record that an address is taken (expression represents an lvalue).
8585  *
8586  * @param expression       the expression
8587  * @param may_be_register  if true, the expression might be an register
8588  */
8589 static void set_address_taken(expression_t *expression, bool may_be_register)
8590 {
8591         if (expression->kind != EXPR_REFERENCE)
8592                 return;
8593
8594         entity_t *const entity = expression->reference.entity;
8595
8596         if (entity->kind != ENTITY_VARIABLE && entity->kind != ENTITY_PARAMETER)
8597                 return;
8598
8599         if (entity->declaration.storage_class == STORAGE_CLASS_REGISTER
8600                         && !may_be_register) {
8601                 errorf(&expression->base.source_position,
8602                                 "address of register %s '%Y' requested",
8603                                 get_entity_kind_name(entity->kind),     entity->base.symbol);
8604         }
8605
8606         if (entity->kind == ENTITY_VARIABLE) {
8607                 entity->variable.address_taken = true;
8608         } else {
8609                 assert(entity->kind == ENTITY_PARAMETER);
8610                 entity->parameter.address_taken = true;
8611         }
8612 }
8613
8614 /**
8615  * Check the semantic of the address taken expression.
8616  */
8617 static void semantic_take_addr(unary_expression_t *expression)
8618 {
8619         expression_t *value = expression->value;
8620         value->base.type    = revert_automatic_type_conversion(value);
8621
8622         type_t *orig_type = value->base.type;
8623         type_t *type      = skip_typeref(orig_type);
8624         if (!is_type_valid(type))
8625                 return;
8626
8627         /* §6.5.3.2 */
8628         if (!is_lvalue(value)) {
8629                 errorf(&expression->base.source_position, "'&' requires an lvalue");
8630         }
8631         if (type->kind == TYPE_BITFIELD) {
8632                 errorf(&expression->base.source_position,
8633                        "'&' not allowed on object with bitfield type '%T'",
8634                        type);
8635         }
8636
8637         set_address_taken(value, false);
8638
8639         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
8640 }
8641
8642 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc) \
8643 static expression_t *parse_##unexpression_type(void)                         \
8644 {                                                                            \
8645         expression_t *unary_expression                                           \
8646                 = allocate_expression_zero(unexpression_type);                       \
8647         eat(token_type);                                                         \
8648         unary_expression->unary.value = parse_sub_expression(PREC_UNARY);        \
8649                                                                                  \
8650         sfunc(&unary_expression->unary);                                         \
8651                                                                                  \
8652         return unary_expression;                                                 \
8653 }
8654
8655 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
8656                                semantic_unexpr_arithmetic)
8657 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
8658                                semantic_unexpr_plus)
8659 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
8660                                semantic_not)
8661 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
8662                                semantic_dereference)
8663 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
8664                                semantic_take_addr)
8665 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
8666                                semantic_unexpr_integer)
8667 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
8668                                semantic_incdec)
8669 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
8670                                semantic_incdec)
8671
8672 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
8673                                                sfunc)                         \
8674 static expression_t *parse_##unexpression_type(expression_t *left)            \
8675 {                                                                             \
8676         expression_t *unary_expression                                            \
8677                 = allocate_expression_zero(unexpression_type);                        \
8678         eat(token_type);                                                          \
8679         unary_expression->unary.value = left;                                     \
8680                                                                                   \
8681         sfunc(&unary_expression->unary);                                          \
8682                                                                               \
8683         return unary_expression;                                                  \
8684 }
8685
8686 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
8687                                        EXPR_UNARY_POSTFIX_INCREMENT,
8688                                        semantic_incdec)
8689 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
8690                                        EXPR_UNARY_POSTFIX_DECREMENT,
8691                                        semantic_incdec)
8692
8693 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
8694 {
8695         /* TODO: handle complex + imaginary types */
8696
8697         type_left  = get_unqualified_type(type_left);
8698         type_right = get_unqualified_type(type_right);
8699
8700         /* § 6.3.1.8 Usual arithmetic conversions */
8701         if (type_left == type_long_double || type_right == type_long_double) {
8702                 return type_long_double;
8703         } else if (type_left == type_double || type_right == type_double) {
8704                 return type_double;
8705         } else if (type_left == type_float || type_right == type_float) {
8706                 return type_float;
8707         }
8708
8709         type_left  = promote_integer(type_left);
8710         type_right = promote_integer(type_right);
8711
8712         if (type_left == type_right)
8713                 return type_left;
8714
8715         bool const signed_left  = is_type_signed(type_left);
8716         bool const signed_right = is_type_signed(type_right);
8717         int const  rank_left    = get_rank(type_left);
8718         int const  rank_right   = get_rank(type_right);
8719
8720         if (signed_left == signed_right)
8721                 return rank_left >= rank_right ? type_left : type_right;
8722
8723         int     s_rank;
8724         int     u_rank;
8725         type_t *s_type;
8726         type_t *u_type;
8727         if (signed_left) {
8728                 s_rank = rank_left;
8729                 s_type = type_left;
8730                 u_rank = rank_right;
8731                 u_type = type_right;
8732         } else {
8733                 s_rank = rank_right;
8734                 s_type = type_right;
8735                 u_rank = rank_left;
8736                 u_type = type_left;
8737         }
8738
8739         if (u_rank >= s_rank)
8740                 return u_type;
8741
8742         /* casting rank to atomic_type_kind is a bit hacky, but makes things
8743          * easier here... */
8744         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
8745                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
8746                 return s_type;
8747
8748         switch (s_rank) {
8749                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
8750                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
8751                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
8752
8753                 default: panic("invalid atomic type");
8754         }
8755 }
8756
8757 /**
8758  * Check the semantic restrictions for a binary expression.
8759  */
8760 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
8761 {
8762         expression_t *const left            = expression->left;
8763         expression_t *const right           = expression->right;
8764         type_t       *const orig_type_left  = left->base.type;
8765         type_t       *const orig_type_right = right->base.type;
8766         type_t       *const type_left       = skip_typeref(orig_type_left);
8767         type_t       *const type_right      = skip_typeref(orig_type_right);
8768
8769         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8770                 /* TODO: improve error message */
8771                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8772                         errorf(&expression->base.source_position,
8773                                "operation needs arithmetic types");
8774                 }
8775                 return;
8776         }
8777
8778         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8779         expression->left      = create_implicit_cast(left, arithmetic_type);
8780         expression->right     = create_implicit_cast(right, arithmetic_type);
8781         expression->base.type = arithmetic_type;
8782 }
8783
8784 static void warn_div_by_zero(binary_expression_t const *const expression)
8785 {
8786         if (!warning.div_by_zero ||
8787             !is_type_integer(expression->base.type))
8788                 return;
8789
8790         expression_t const *const right = expression->right;
8791         /* The type of the right operand can be different for /= */
8792         if (is_type_integer(right->base.type) &&
8793             is_constant_expression(right)     &&
8794             fold_constant(right) == 0) {
8795                 warningf(&expression->base.source_position, "division by zero");
8796         }
8797 }
8798
8799 /**
8800  * Check the semantic restrictions for a div/mod expression.
8801  */
8802 static void semantic_divmod_arithmetic(binary_expression_t *expression) {
8803         semantic_binexpr_arithmetic(expression);
8804         warn_div_by_zero(expression);
8805 }
8806
8807 static void semantic_shift_op(binary_expression_t *expression)
8808 {
8809         expression_t *const left            = expression->left;
8810         expression_t *const right           = expression->right;
8811         type_t       *const orig_type_left  = left->base.type;
8812         type_t       *const orig_type_right = right->base.type;
8813         type_t       *      type_left       = skip_typeref(orig_type_left);
8814         type_t       *      type_right      = skip_typeref(orig_type_right);
8815
8816         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8817                 /* TODO: improve error message */
8818                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8819                         errorf(&expression->base.source_position,
8820                                "operands of shift operation must have integer types");
8821                 }
8822                 return;
8823         }
8824
8825         type_left  = promote_integer(type_left);
8826         type_right = promote_integer(type_right);
8827
8828         expression->left      = create_implicit_cast(left, type_left);
8829         expression->right     = create_implicit_cast(right, type_right);
8830         expression->base.type = type_left;
8831 }
8832
8833 static void semantic_add(binary_expression_t *expression)
8834 {
8835         expression_t *const left            = expression->left;
8836         expression_t *const right           = expression->right;
8837         type_t       *const orig_type_left  = left->base.type;
8838         type_t       *const orig_type_right = right->base.type;
8839         type_t       *const type_left       = skip_typeref(orig_type_left);
8840         type_t       *const type_right      = skip_typeref(orig_type_right);
8841
8842         /* § 6.5.6 */
8843         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8844                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8845                 expression->left  = create_implicit_cast(left, arithmetic_type);
8846                 expression->right = create_implicit_cast(right, arithmetic_type);
8847                 expression->base.type = arithmetic_type;
8848                 return;
8849         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8850                 check_pointer_arithmetic(&expression->base.source_position,
8851                                          type_left, orig_type_left);
8852                 expression->base.type = type_left;
8853         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
8854                 check_pointer_arithmetic(&expression->base.source_position,
8855                                          type_right, orig_type_right);
8856                 expression->base.type = type_right;
8857         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8858                 errorf(&expression->base.source_position,
8859                        "invalid operands to binary + ('%T', '%T')",
8860                        orig_type_left, orig_type_right);
8861         }
8862 }
8863
8864 static void semantic_sub(binary_expression_t *expression)
8865 {
8866         expression_t            *const left            = expression->left;
8867         expression_t            *const right           = expression->right;
8868         type_t                  *const orig_type_left  = left->base.type;
8869         type_t                  *const orig_type_right = right->base.type;
8870         type_t                  *const type_left       = skip_typeref(orig_type_left);
8871         type_t                  *const type_right      = skip_typeref(orig_type_right);
8872         source_position_t const *const pos             = &expression->base.source_position;
8873
8874         /* § 5.6.5 */
8875         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8876                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8877                 expression->left        = create_implicit_cast(left, arithmetic_type);
8878                 expression->right       = create_implicit_cast(right, arithmetic_type);
8879                 expression->base.type =  arithmetic_type;
8880                 return;
8881         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8882                 check_pointer_arithmetic(&expression->base.source_position,
8883                                          type_left, orig_type_left);
8884                 expression->base.type = type_left;
8885         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8886                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
8887                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
8888                 if (!types_compatible(unqual_left, unqual_right)) {
8889                         errorf(pos,
8890                                "subtracting pointers to incompatible types '%T' and '%T'",
8891                                orig_type_left, orig_type_right);
8892                 } else if (!is_type_object(unqual_left)) {
8893                         if (!is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
8894                                 errorf(pos, "subtracting pointers to non-object types '%T'",
8895                                        orig_type_left);
8896                         } else if (warning.other) {
8897                                 warningf(pos, "subtracting pointers to void");
8898                         }
8899                 }
8900                 expression->base.type = type_ptrdiff_t;
8901         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8902                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
8903                        orig_type_left, orig_type_right);
8904         }
8905 }
8906
8907 static void warn_string_literal_address(expression_t const* expr)
8908 {
8909         while (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8910                 expr = expr->unary.value;
8911                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8912                         return;
8913                 expr = expr->unary.value;
8914         }
8915
8916         if (expr->kind == EXPR_STRING_LITERAL ||
8917             expr->kind == EXPR_WIDE_STRING_LITERAL) {
8918                 warningf(&expr->base.source_position,
8919                         "comparison with string literal results in unspecified behaviour");
8920         }
8921 }
8922
8923 /**
8924  * Check the semantics of comparison expressions.
8925  *
8926  * @param expression   The expression to check.
8927  */
8928 static void semantic_comparison(binary_expression_t *expression)
8929 {
8930         expression_t *left  = expression->left;
8931         expression_t *right = expression->right;
8932
8933         if (warning.address) {
8934                 warn_string_literal_address(left);
8935                 warn_string_literal_address(right);
8936
8937                 expression_t const* const func_left = get_reference_address(left);
8938                 if (func_left != NULL && is_null_pointer_constant(right)) {
8939                         warningf(&expression->base.source_position,
8940                                  "the address of '%Y' will never be NULL",
8941                                  func_left->reference.entity->base.symbol);
8942                 }
8943
8944                 expression_t const* const func_right = get_reference_address(right);
8945                 if (func_right != NULL && is_null_pointer_constant(right)) {
8946                         warningf(&expression->base.source_position,
8947                                  "the address of '%Y' will never be NULL",
8948                                  func_right->reference.entity->base.symbol);
8949                 }
8950         }
8951
8952         type_t *orig_type_left  = left->base.type;
8953         type_t *orig_type_right = right->base.type;
8954         type_t *type_left       = skip_typeref(orig_type_left);
8955         type_t *type_right      = skip_typeref(orig_type_right);
8956
8957         /* TODO non-arithmetic types */
8958         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8959                 /* test for signed vs unsigned compares */
8960                 if (warning.sign_compare &&
8961                     (expression->base.kind != EXPR_BINARY_EQUAL &&
8962                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
8963                     (is_type_signed(type_left) != is_type_signed(type_right))) {
8964
8965                         /* check if 1 of the operands is a constant, in this case we just
8966                          * check wether we can safely represent the resulting constant in
8967                          * the type of the other operand. */
8968                         expression_t *const_expr = NULL;
8969                         expression_t *other_expr = NULL;
8970
8971                         if (is_constant_expression(left)) {
8972                                 const_expr = left;
8973                                 other_expr = right;
8974                         } else if (is_constant_expression(right)) {
8975                                 const_expr = right;
8976                                 other_expr = left;
8977                         }
8978
8979                         if (const_expr != NULL) {
8980                                 type_t *other_type = skip_typeref(other_expr->base.type);
8981                                 long    val        = fold_constant(const_expr);
8982                                 /* TODO: check if val can be represented by other_type */
8983                                 (void) other_type;
8984                                 (void) val;
8985                         }
8986                         warningf(&expression->base.source_position,
8987                                  "comparison between signed and unsigned");
8988                 }
8989                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8990                 expression->left        = create_implicit_cast(left, arithmetic_type);
8991                 expression->right       = create_implicit_cast(right, arithmetic_type);
8992                 expression->base.type   = arithmetic_type;
8993                 if (warning.float_equal &&
8994                     (expression->base.kind == EXPR_BINARY_EQUAL ||
8995                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
8996                     is_type_float(arithmetic_type)) {
8997                         warningf(&expression->base.source_position,
8998                                  "comparing floating point with == or != is unsafe");
8999                 }
9000         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
9001                 /* TODO check compatibility */
9002         } else if (is_type_pointer(type_left)) {
9003                 expression->right = create_implicit_cast(right, type_left);
9004         } else if (is_type_pointer(type_right)) {
9005                 expression->left = create_implicit_cast(left, type_right);
9006         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9007                 type_error_incompatible("invalid operands in comparison",
9008                                         &expression->base.source_position,
9009                                         type_left, type_right);
9010         }
9011         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9012 }
9013
9014 /**
9015  * Checks if a compound type has constant fields.
9016  */
9017 static bool has_const_fields(const compound_type_t *type)
9018 {
9019         compound_t *compound = type->compound;
9020         entity_t   *entry    = compound->members.entities;
9021
9022         for (; entry != NULL; entry = entry->base.next) {
9023                 if (!is_declaration(entry))
9024                         continue;
9025
9026                 const type_t *decl_type = skip_typeref(entry->declaration.type);
9027                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
9028                         return true;
9029         }
9030
9031         return false;
9032 }
9033
9034 static bool is_valid_assignment_lhs(expression_t const* const left)
9035 {
9036         type_t *const orig_type_left = revert_automatic_type_conversion(left);
9037         type_t *const type_left      = skip_typeref(orig_type_left);
9038
9039         if (!is_lvalue(left)) {
9040                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
9041                        left);
9042                 return false;
9043         }
9044
9045         if (left->kind == EXPR_REFERENCE
9046                         && left->reference.entity->kind == ENTITY_FUNCTION) {
9047                 errorf(HERE, "cannot assign to function '%E'", left);
9048                 return false;
9049         }
9050
9051         if (is_type_array(type_left)) {
9052                 errorf(HERE, "cannot assign to array '%E'", left);
9053                 return false;
9054         }
9055         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
9056                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
9057                        orig_type_left);
9058                 return false;
9059         }
9060         if (is_type_incomplete(type_left)) {
9061                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
9062                        left, orig_type_left);
9063                 return false;
9064         }
9065         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
9066                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
9067                        left, orig_type_left);
9068                 return false;
9069         }
9070
9071         return true;
9072 }
9073
9074 static void semantic_arithmetic_assign(binary_expression_t *expression)
9075 {
9076         expression_t *left            = expression->left;
9077         expression_t *right           = expression->right;
9078         type_t       *orig_type_left  = left->base.type;
9079         type_t       *orig_type_right = right->base.type;
9080
9081         if (!is_valid_assignment_lhs(left))
9082                 return;
9083
9084         type_t *type_left  = skip_typeref(orig_type_left);
9085         type_t *type_right = skip_typeref(orig_type_right);
9086
9087         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
9088                 /* TODO: improve error message */
9089                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
9090                         errorf(&expression->base.source_position,
9091                                "operation needs arithmetic types");
9092                 }
9093                 return;
9094         }
9095
9096         /* combined instructions are tricky. We can't create an implicit cast on
9097          * the left side, because we need the uncasted form for the store.
9098          * The ast2firm pass has to know that left_type must be right_type
9099          * for the arithmetic operation and create a cast by itself */
9100         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
9101         expression->right       = create_implicit_cast(right, arithmetic_type);
9102         expression->base.type   = type_left;
9103 }
9104
9105 static void semantic_divmod_assign(binary_expression_t *expression)
9106 {
9107         semantic_arithmetic_assign(expression);
9108         warn_div_by_zero(expression);
9109 }
9110
9111 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
9112 {
9113         expression_t *const left            = expression->left;
9114         expression_t *const right           = expression->right;
9115         type_t       *const orig_type_left  = left->base.type;
9116         type_t       *const orig_type_right = right->base.type;
9117         type_t       *const type_left       = skip_typeref(orig_type_left);
9118         type_t       *const type_right      = skip_typeref(orig_type_right);
9119
9120         if (!is_valid_assignment_lhs(left))
9121                 return;
9122
9123         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
9124                 /* combined instructions are tricky. We can't create an implicit cast on
9125                  * the left side, because we need the uncasted form for the store.
9126                  * The ast2firm pass has to know that left_type must be right_type
9127                  * for the arithmetic operation and create a cast by itself */
9128                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
9129                 expression->right     = create_implicit_cast(right, arithmetic_type);
9130                 expression->base.type = type_left;
9131         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
9132                 check_pointer_arithmetic(&expression->base.source_position,
9133                                          type_left, orig_type_left);
9134                 expression->base.type = type_left;
9135         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
9136                 errorf(&expression->base.source_position,
9137                        "incompatible types '%T' and '%T' in assignment",
9138                        orig_type_left, orig_type_right);
9139         }
9140 }
9141
9142 /**
9143  * Check the semantic restrictions of a logical expression.
9144  */
9145 static void semantic_logical_op(binary_expression_t *expression)
9146 {
9147         /* §6.5.13:2  Each of the operands shall have scalar type.
9148          * §6.5.14:2  Each of the operands shall have scalar type. */
9149         semantic_condition(expression->left,   "left operand of logical operator");
9150         semantic_condition(expression->right, "right operand of logical operator");
9151         expression->base.type = c_mode & _CXX ? type_bool : type_int;
9152 }
9153
9154 /**
9155  * Check the semantic restrictions of a binary assign expression.
9156  */
9157 static void semantic_binexpr_assign(binary_expression_t *expression)
9158 {
9159         expression_t *left           = expression->left;
9160         type_t       *orig_type_left = left->base.type;
9161
9162         if (!is_valid_assignment_lhs(left))
9163                 return;
9164
9165         assign_error_t error = semantic_assign(orig_type_left, expression->right);
9166         report_assign_error(error, orig_type_left, expression->right,
9167                         "assignment", &left->base.source_position);
9168         expression->right = create_implicit_cast(expression->right, orig_type_left);
9169         expression->base.type = orig_type_left;
9170 }
9171
9172 /**
9173  * Determine if the outermost operation (or parts thereof) of the given
9174  * expression has no effect in order to generate a warning about this fact.
9175  * Therefore in some cases this only examines some of the operands of the
9176  * expression (see comments in the function and examples below).
9177  * Examples:
9178  *   f() + 23;    // warning, because + has no effect
9179  *   x || f();    // no warning, because x controls execution of f()
9180  *   x ? y : f(); // warning, because y has no effect
9181  *   (void)x;     // no warning to be able to suppress the warning
9182  * This function can NOT be used for an "expression has definitely no effect"-
9183  * analysis. */
9184 static bool expression_has_effect(const expression_t *const expr)
9185 {
9186         switch (expr->kind) {
9187                 case EXPR_UNKNOWN:                   break;
9188                 case EXPR_INVALID:                   return true; /* do NOT warn */
9189                 case EXPR_REFERENCE:                 return false;
9190                 case EXPR_REFERENCE_ENUM_VALUE:      return false;
9191                 /* suppress the warning for microsoft __noop operations */
9192                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
9193                 case EXPR_CHARACTER_CONSTANT:        return false;
9194                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
9195                 case EXPR_STRING_LITERAL:            return false;
9196                 case EXPR_WIDE_STRING_LITERAL:       return false;
9197                 case EXPR_LABEL_ADDRESS:             return false;
9198
9199                 case EXPR_CALL: {
9200                         const call_expression_t *const call = &expr->call;
9201                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
9202                                 return true;
9203
9204                         switch (call->function->builtin_symbol.symbol->ID) {
9205                                 case T___builtin_va_end: return true;
9206                                 default:                 return false;
9207                         }
9208                 }
9209
9210                 /* Generate the warning if either the left or right hand side of a
9211                  * conditional expression has no effect */
9212                 case EXPR_CONDITIONAL: {
9213                         const conditional_expression_t *const cond = &expr->conditional;
9214                         return
9215                                 expression_has_effect(cond->true_expression) &&
9216                                 expression_has_effect(cond->false_expression);
9217                 }
9218
9219                 case EXPR_SELECT:                    return false;
9220                 case EXPR_ARRAY_ACCESS:              return false;
9221                 case EXPR_SIZEOF:                    return false;
9222                 case EXPR_CLASSIFY_TYPE:             return false;
9223                 case EXPR_ALIGNOF:                   return false;
9224
9225                 case EXPR_FUNCNAME:                  return false;
9226                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
9227                 case EXPR_BUILTIN_CONSTANT_P:        return false;
9228                 case EXPR_BUILTIN_PREFETCH:          return true;
9229                 case EXPR_OFFSETOF:                  return false;
9230                 case EXPR_VA_START:                  return true;
9231                 case EXPR_VA_ARG:                    return true;
9232                 case EXPR_STATEMENT:                 return true; // TODO
9233                 case EXPR_COMPOUND_LITERAL:          return false;
9234
9235                 case EXPR_UNARY_NEGATE:              return false;
9236                 case EXPR_UNARY_PLUS:                return false;
9237                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
9238                 case EXPR_UNARY_NOT:                 return false;
9239                 case EXPR_UNARY_DEREFERENCE:         return false;
9240                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
9241                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
9242                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
9243                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
9244                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
9245
9246                 /* Treat void casts as if they have an effect in order to being able to
9247                  * suppress the warning */
9248                 case EXPR_UNARY_CAST: {
9249                         type_t *const type = skip_typeref(expr->base.type);
9250                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
9251                 }
9252
9253                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
9254                 case EXPR_UNARY_ASSUME:              return true;
9255                 case EXPR_UNARY_DELETE:              return true;
9256                 case EXPR_UNARY_DELETE_ARRAY:        return true;
9257                 case EXPR_UNARY_THROW:               return true;
9258
9259                 case EXPR_BINARY_ADD:                return false;
9260                 case EXPR_BINARY_SUB:                return false;
9261                 case EXPR_BINARY_MUL:                return false;
9262                 case EXPR_BINARY_DIV:                return false;
9263                 case EXPR_BINARY_MOD:                return false;
9264                 case EXPR_BINARY_EQUAL:              return false;
9265                 case EXPR_BINARY_NOTEQUAL:           return false;
9266                 case EXPR_BINARY_LESS:               return false;
9267                 case EXPR_BINARY_LESSEQUAL:          return false;
9268                 case EXPR_BINARY_GREATER:            return false;
9269                 case EXPR_BINARY_GREATEREQUAL:       return false;
9270                 case EXPR_BINARY_BITWISE_AND:        return false;
9271                 case EXPR_BINARY_BITWISE_OR:         return false;
9272                 case EXPR_BINARY_BITWISE_XOR:        return false;
9273                 case EXPR_BINARY_SHIFTLEFT:          return false;
9274                 case EXPR_BINARY_SHIFTRIGHT:         return false;
9275                 case EXPR_BINARY_ASSIGN:             return true;
9276                 case EXPR_BINARY_MUL_ASSIGN:         return true;
9277                 case EXPR_BINARY_DIV_ASSIGN:         return true;
9278                 case EXPR_BINARY_MOD_ASSIGN:         return true;
9279                 case EXPR_BINARY_ADD_ASSIGN:         return true;
9280                 case EXPR_BINARY_SUB_ASSIGN:         return true;
9281                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
9282                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
9283                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
9284                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
9285                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
9286
9287                 /* Only examine the right hand side of && and ||, because the left hand
9288                  * side already has the effect of controlling the execution of the right
9289                  * hand side */
9290                 case EXPR_BINARY_LOGICAL_AND:
9291                 case EXPR_BINARY_LOGICAL_OR:
9292                 /* Only examine the right hand side of a comma expression, because the left
9293                  * hand side has a separate warning */
9294                 case EXPR_BINARY_COMMA:
9295                         return expression_has_effect(expr->binary.right);
9296
9297                 case EXPR_BINARY_ISGREATER:          return false;
9298                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
9299                 case EXPR_BINARY_ISLESS:             return false;
9300                 case EXPR_BINARY_ISLESSEQUAL:        return false;
9301                 case EXPR_BINARY_ISLESSGREATER:      return false;
9302                 case EXPR_BINARY_ISUNORDERED:        return false;
9303         }
9304
9305         internal_errorf(HERE, "unexpected expression");
9306 }
9307
9308 static void semantic_comma(binary_expression_t *expression)
9309 {
9310         if (warning.unused_value) {
9311                 const expression_t *const left = expression->left;
9312                 if (!expression_has_effect(left)) {
9313                         warningf(&left->base.source_position,
9314                                  "left-hand operand of comma expression has no effect");
9315                 }
9316         }
9317         expression->base.type = expression->right->base.type;
9318 }
9319
9320 /**
9321  * @param prec_r precedence of the right operand
9322  */
9323 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, prec_r, sfunc) \
9324 static expression_t *parse_##binexpression_type(expression_t *left)          \
9325 {                                                                            \
9326         expression_t *binexpr = allocate_expression_zero(binexpression_type);    \
9327         binexpr->binary.left  = left;                                            \
9328         eat(token_type);                                                         \
9329                                                                              \
9330         expression_t *right = parse_sub_expression(prec_r);                      \
9331                                                                              \
9332         binexpr->binary.right = right;                                           \
9333         sfunc(&binexpr->binary);                                                 \
9334                                                                              \
9335         return binexpr;                                                          \
9336 }
9337
9338 CREATE_BINEXPR_PARSER('*',                    EXPR_BINARY_MUL,                PREC_CAST,           semantic_binexpr_arithmetic)
9339 CREATE_BINEXPR_PARSER('/',                    EXPR_BINARY_DIV,                PREC_CAST,           semantic_divmod_arithmetic)
9340 CREATE_BINEXPR_PARSER('%',                    EXPR_BINARY_MOD,                PREC_CAST,           semantic_divmod_arithmetic)
9341 CREATE_BINEXPR_PARSER('+',                    EXPR_BINARY_ADD,                PREC_MULTIPLICATIVE, semantic_add)
9342 CREATE_BINEXPR_PARSER('-',                    EXPR_BINARY_SUB,                PREC_MULTIPLICATIVE, semantic_sub)
9343 CREATE_BINEXPR_PARSER(T_LESSLESS,             EXPR_BINARY_SHIFTLEFT,          PREC_ADDITIVE,       semantic_shift_op)
9344 CREATE_BINEXPR_PARSER(T_GREATERGREATER,       EXPR_BINARY_SHIFTRIGHT,         PREC_ADDITIVE,       semantic_shift_op)
9345 CREATE_BINEXPR_PARSER('<',                    EXPR_BINARY_LESS,               PREC_SHIFT,          semantic_comparison)
9346 CREATE_BINEXPR_PARSER('>',                    EXPR_BINARY_GREATER,            PREC_SHIFT,          semantic_comparison)
9347 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,          PREC_SHIFT,          semantic_comparison)
9348 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,       PREC_SHIFT,          semantic_comparison)
9349 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,           PREC_RELATIONAL,     semantic_comparison)
9350 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,              PREC_RELATIONAL,     semantic_comparison)
9351 CREATE_BINEXPR_PARSER('&',                    EXPR_BINARY_BITWISE_AND,        PREC_EQUALITY,       semantic_binexpr_arithmetic)
9352 CREATE_BINEXPR_PARSER('^',                    EXPR_BINARY_BITWISE_XOR,        PREC_AND,            semantic_binexpr_arithmetic)
9353 CREATE_BINEXPR_PARSER('|',                    EXPR_BINARY_BITWISE_OR,         PREC_XOR,            semantic_binexpr_arithmetic)
9354 CREATE_BINEXPR_PARSER(T_ANDAND,               EXPR_BINARY_LOGICAL_AND,        PREC_OR,             semantic_logical_op)
9355 CREATE_BINEXPR_PARSER(T_PIPEPIPE,             EXPR_BINARY_LOGICAL_OR,         PREC_LOGICAL_AND,    semantic_logical_op)
9356 CREATE_BINEXPR_PARSER('=',                    EXPR_BINARY_ASSIGN,             PREC_ASSIGNMENT,     semantic_binexpr_assign)
9357 CREATE_BINEXPR_PARSER(T_PLUSEQUAL,            EXPR_BINARY_ADD_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9358 CREATE_BINEXPR_PARSER(T_MINUSEQUAL,           EXPR_BINARY_SUB_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
9359 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL,        EXPR_BINARY_MUL_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9360 CREATE_BINEXPR_PARSER(T_SLASHEQUAL,           EXPR_BINARY_DIV_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9361 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL,         EXPR_BINARY_MOD_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9362 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL,        EXPR_BINARY_SHIFTLEFT_ASSIGN,   PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9363 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL,  EXPR_BINARY_SHIFTRIGHT_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9364 CREATE_BINEXPR_PARSER(T_ANDEQUAL,             EXPR_BINARY_BITWISE_AND_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9365 CREATE_BINEXPR_PARSER(T_PIPEEQUAL,            EXPR_BINARY_BITWISE_OR_ASSIGN,  PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9366 CREATE_BINEXPR_PARSER(T_CARETEQUAL,           EXPR_BINARY_BITWISE_XOR_ASSIGN, PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9367 CREATE_BINEXPR_PARSER(',',                    EXPR_BINARY_COMMA,              PREC_ASSIGNMENT,     semantic_comma)
9368
9369
9370 static expression_t *parse_sub_expression(precedence_t precedence)
9371 {
9372         if (token.type < 0) {
9373                 return expected_expression_error();
9374         }
9375
9376         expression_parser_function_t *parser
9377                 = &expression_parsers[token.type];
9378         source_position_t             source_position = token.source_position;
9379         expression_t                 *left;
9380
9381         if (parser->parser != NULL) {
9382                 left = parser->parser();
9383         } else {
9384                 left = parse_primary_expression();
9385         }
9386         assert(left != NULL);
9387         left->base.source_position = source_position;
9388
9389         while (true) {
9390                 if (token.type < 0) {
9391                         return expected_expression_error();
9392                 }
9393
9394                 parser = &expression_parsers[token.type];
9395                 if (parser->infix_parser == NULL)
9396                         break;
9397                 if (parser->infix_precedence < precedence)
9398                         break;
9399
9400                 left = parser->infix_parser(left);
9401
9402                 assert(left != NULL);
9403                 assert(left->kind != EXPR_UNKNOWN);
9404                 left->base.source_position = source_position;
9405         }
9406
9407         return left;
9408 }
9409
9410 /**
9411  * Parse an expression.
9412  */
9413 static expression_t *parse_expression(void)
9414 {
9415         return parse_sub_expression(PREC_EXPRESSION);
9416 }
9417
9418 /**
9419  * Register a parser for a prefix-like operator.
9420  *
9421  * @param parser      the parser function
9422  * @param token_type  the token type of the prefix token
9423  */
9424 static void register_expression_parser(parse_expression_function parser,
9425                                        int token_type)
9426 {
9427         expression_parser_function_t *entry = &expression_parsers[token_type];
9428
9429         if (entry->parser != NULL) {
9430                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9431                 panic("trying to register multiple expression parsers for a token");
9432         }
9433         entry->parser = parser;
9434 }
9435
9436 /**
9437  * Register a parser for an infix operator with given precedence.
9438  *
9439  * @param parser      the parser function
9440  * @param token_type  the token type of the infix operator
9441  * @param precedence  the precedence of the operator
9442  */
9443 static void register_infix_parser(parse_expression_infix_function parser,
9444                 int token_type, unsigned precedence)
9445 {
9446         expression_parser_function_t *entry = &expression_parsers[token_type];
9447
9448         if (entry->infix_parser != NULL) {
9449                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9450                 panic("trying to register multiple infix expression parsers for a "
9451                       "token");
9452         }
9453         entry->infix_parser     = parser;
9454         entry->infix_precedence = precedence;
9455 }
9456
9457 /**
9458  * Initialize the expression parsers.
9459  */
9460 static void init_expression_parsers(void)
9461 {
9462         memset(&expression_parsers, 0, sizeof(expression_parsers));
9463
9464         register_infix_parser(parse_array_expression,               '[',                    PREC_POSTFIX);
9465         register_infix_parser(parse_call_expression,                '(',                    PREC_POSTFIX);
9466         register_infix_parser(parse_select_expression,              '.',                    PREC_POSTFIX);
9467         register_infix_parser(parse_select_expression,              T_MINUSGREATER,         PREC_POSTFIX);
9468         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,   T_PLUSPLUS,             PREC_POSTFIX);
9469         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,   T_MINUSMINUS,           PREC_POSTFIX);
9470         register_infix_parser(parse_EXPR_BINARY_MUL,                '*',                    PREC_MULTIPLICATIVE);
9471         register_infix_parser(parse_EXPR_BINARY_DIV,                '/',                    PREC_MULTIPLICATIVE);
9472         register_infix_parser(parse_EXPR_BINARY_MOD,                '%',                    PREC_MULTIPLICATIVE);
9473         register_infix_parser(parse_EXPR_BINARY_ADD,                '+',                    PREC_ADDITIVE);
9474         register_infix_parser(parse_EXPR_BINARY_SUB,                '-',                    PREC_ADDITIVE);
9475         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,          T_LESSLESS,             PREC_SHIFT);
9476         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,         T_GREATERGREATER,       PREC_SHIFT);
9477         register_infix_parser(parse_EXPR_BINARY_LESS,               '<',                    PREC_RELATIONAL);
9478         register_infix_parser(parse_EXPR_BINARY_GREATER,            '>',                    PREC_RELATIONAL);
9479         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,          T_LESSEQUAL,            PREC_RELATIONAL);
9480         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL,       T_GREATEREQUAL,         PREC_RELATIONAL);
9481         register_infix_parser(parse_EXPR_BINARY_EQUAL,              T_EQUALEQUAL,           PREC_EQUALITY);
9482         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,           T_EXCLAMATIONMARKEQUAL, PREC_EQUALITY);
9483         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,        '&',                    PREC_AND);
9484         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,        '^',                    PREC_XOR);
9485         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,         '|',                    PREC_OR);
9486         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,        T_ANDAND,               PREC_LOGICAL_AND);
9487         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,         T_PIPEPIPE,             PREC_LOGICAL_OR);
9488         register_infix_parser(parse_conditional_expression,         '?',                    PREC_CONDITIONAL);
9489         register_infix_parser(parse_EXPR_BINARY_ASSIGN,             '=',                    PREC_ASSIGNMENT);
9490         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,         T_PLUSEQUAL,            PREC_ASSIGNMENT);
9491         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,         T_MINUSEQUAL,           PREC_ASSIGNMENT);
9492         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,         T_ASTERISKEQUAL,        PREC_ASSIGNMENT);
9493         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,         T_SLASHEQUAL,           PREC_ASSIGNMENT);
9494         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,         T_PERCENTEQUAL,         PREC_ASSIGNMENT);
9495         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,   T_LESSLESSEQUAL,        PREC_ASSIGNMENT);
9496         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,  T_GREATERGREATEREQUAL,  PREC_ASSIGNMENT);
9497         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN, T_ANDEQUAL,             PREC_ASSIGNMENT);
9498         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,  T_PIPEEQUAL,            PREC_ASSIGNMENT);
9499         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN, T_CARETEQUAL,           PREC_ASSIGNMENT);
9500         register_infix_parser(parse_EXPR_BINARY_COMMA,              ',',                    PREC_EXPRESSION);
9501
9502         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-');
9503         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+');
9504         register_expression_parser(parse_EXPR_UNARY_NOT,              '!');
9505         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~');
9506         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*');
9507         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&');
9508         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT, T_PLUSPLUS);
9509         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT, T_MINUSMINUS);
9510         register_expression_parser(parse_sizeof,                      T_sizeof);
9511         register_expression_parser(parse_alignof,                     T___alignof__);
9512         register_expression_parser(parse_extension,                   T___extension__);
9513         register_expression_parser(parse_builtin_classify_type,       T___builtin_classify_type);
9514         register_expression_parser(parse_delete,                      T_delete);
9515         register_expression_parser(parse_throw,                       T_throw);
9516 }
9517
9518 /**
9519  * Parse a asm statement arguments specification.
9520  */
9521 static asm_argument_t *parse_asm_arguments(bool is_out)
9522 {
9523         asm_argument_t  *result = NULL;
9524         asm_argument_t **anchor = &result;
9525
9526         while (token.type == T_STRING_LITERAL || token.type == '[') {
9527                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
9528                 memset(argument, 0, sizeof(argument[0]));
9529
9530                 if (token.type == '[') {
9531                         eat('[');
9532                         if (token.type != T_IDENTIFIER) {
9533                                 parse_error_expected("while parsing asm argument",
9534                                                      T_IDENTIFIER, NULL);
9535                                 return NULL;
9536                         }
9537                         argument->symbol = token.v.symbol;
9538
9539                         expect(']', end_error);
9540                 }
9541
9542                 argument->constraints = parse_string_literals();
9543                 expect('(', end_error);
9544                 add_anchor_token(')');
9545                 expression_t *expression = parse_expression();
9546                 rem_anchor_token(')');
9547                 if (is_out) {
9548                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
9549                          * change size or type representation (e.g. int -> long is ok, but
9550                          * int -> float is not) */
9551                         if (expression->kind == EXPR_UNARY_CAST) {
9552                                 type_t      *const type = expression->base.type;
9553                                 type_kind_t  const kind = type->kind;
9554                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
9555                                         unsigned flags;
9556                                         unsigned size;
9557                                         if (kind == TYPE_ATOMIC) {
9558                                                 atomic_type_kind_t const akind = type->atomic.akind;
9559                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9560                                                 size  = get_atomic_type_size(akind);
9561                                         } else {
9562                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9563                                                 size  = get_atomic_type_size(get_intptr_kind());
9564                                         }
9565
9566                                         do {
9567                                                 expression_t *const value      = expression->unary.value;
9568                                                 type_t       *const value_type = value->base.type;
9569                                                 type_kind_t   const value_kind = value_type->kind;
9570
9571                                                 unsigned value_flags;
9572                                                 unsigned value_size;
9573                                                 if (value_kind == TYPE_ATOMIC) {
9574                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
9575                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9576                                                         value_size  = get_atomic_type_size(value_akind);
9577                                                 } else if (value_kind == TYPE_POINTER) {
9578                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9579                                                         value_size  = get_atomic_type_size(get_intptr_kind());
9580                                                 } else {
9581                                                         break;
9582                                                 }
9583
9584                                                 if (value_flags != flags || value_size != size)
9585                                                         break;
9586
9587                                                 expression = value;
9588                                         } while (expression->kind == EXPR_UNARY_CAST);
9589                                 }
9590                         }
9591
9592                         if (!is_lvalue(expression)) {
9593                                 errorf(&expression->base.source_position,
9594                                        "asm output argument is not an lvalue");
9595                         }
9596
9597                         if (argument->constraints.begin[0] == '+')
9598                                 mark_vars_read(expression, NULL);
9599                 } else {
9600                         mark_vars_read(expression, NULL);
9601                 }
9602                 argument->expression = expression;
9603                 expect(')', end_error);
9604
9605                 set_address_taken(expression, true);
9606
9607                 *anchor = argument;
9608                 anchor  = &argument->next;
9609
9610                 if (token.type != ',')
9611                         break;
9612                 eat(',');
9613         }
9614
9615         return result;
9616 end_error:
9617         return NULL;
9618 }
9619
9620 /**
9621  * Parse a asm statement clobber specification.
9622  */
9623 static asm_clobber_t *parse_asm_clobbers(void)
9624 {
9625         asm_clobber_t *result = NULL;
9626         asm_clobber_t *last   = NULL;
9627
9628         while (token.type == T_STRING_LITERAL) {
9629                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
9630                 clobber->clobber       = parse_string_literals();
9631
9632                 if (last != NULL) {
9633                         last->next = clobber;
9634                 } else {
9635                         result = clobber;
9636                 }
9637                 last = clobber;
9638
9639                 if (token.type != ',')
9640                         break;
9641                 eat(',');
9642         }
9643
9644         return result;
9645 }
9646
9647 /**
9648  * Parse an asm statement.
9649  */
9650 static statement_t *parse_asm_statement(void)
9651 {
9652         statement_t     *statement     = allocate_statement_zero(STATEMENT_ASM);
9653         asm_statement_t *asm_statement = &statement->asms;
9654
9655         eat(T_asm);
9656
9657         if (token.type == T_volatile) {
9658                 next_token();
9659                 asm_statement->is_volatile = true;
9660         }
9661
9662         expect('(', end_error);
9663         add_anchor_token(')');
9664         add_anchor_token(':');
9665         asm_statement->asm_text = parse_string_literals();
9666
9667         if (token.type != ':') {
9668                 rem_anchor_token(':');
9669                 goto end_of_asm;
9670         }
9671         eat(':');
9672
9673         asm_statement->outputs = parse_asm_arguments(true);
9674         if (token.type != ':') {
9675                 rem_anchor_token(':');
9676                 goto end_of_asm;
9677         }
9678         eat(':');
9679
9680         asm_statement->inputs = parse_asm_arguments(false);
9681         if (token.type != ':') {
9682                 rem_anchor_token(':');
9683                 goto end_of_asm;
9684         }
9685         rem_anchor_token(':');
9686         eat(':');
9687
9688         asm_statement->clobbers = parse_asm_clobbers();
9689
9690 end_of_asm:
9691         rem_anchor_token(')');
9692         expect(')', end_error);
9693         expect(';', end_error);
9694
9695         if (asm_statement->outputs == NULL) {
9696                 /* GCC: An 'asm' instruction without any output operands will be treated
9697                  * identically to a volatile 'asm' instruction. */
9698                 asm_statement->is_volatile = true;
9699         }
9700
9701         return statement;
9702 end_error:
9703         return create_invalid_statement();
9704 }
9705
9706 /**
9707  * Parse a case statement.
9708  */
9709 static statement_t *parse_case_statement(void)
9710 {
9711         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9712         source_position_t *const pos       = &statement->base.source_position;
9713
9714         eat(T_case);
9715
9716         expression_t *const expression   = parse_expression();
9717         statement->case_label.expression = expression;
9718         if (!is_constant_expression(expression)) {
9719                 /* This check does not prevent the error message in all cases of an
9720                  * prior error while parsing the expression.  At least it catches the
9721                  * common case of a mistyped enum entry. */
9722                 if (is_type_valid(skip_typeref(expression->base.type))) {
9723                         errorf(pos, "case label does not reduce to an integer constant");
9724                 }
9725                 statement->case_label.is_bad = true;
9726         } else {
9727                 long const val = fold_constant(expression);
9728                 statement->case_label.first_case = val;
9729                 statement->case_label.last_case  = val;
9730         }
9731
9732         if (GNU_MODE) {
9733                 if (token.type == T_DOTDOTDOT) {
9734                         next_token();
9735                         expression_t *const end_range   = parse_expression();
9736                         statement->case_label.end_range = end_range;
9737                         if (!is_constant_expression(end_range)) {
9738                                 /* This check does not prevent the error message in all cases of an
9739                                  * prior error while parsing the expression.  At least it catches the
9740                                  * common case of a mistyped enum entry. */
9741                                 if (is_type_valid(skip_typeref(end_range->base.type))) {
9742                                         errorf(pos, "case range does not reduce to an integer constant");
9743                                 }
9744                                 statement->case_label.is_bad = true;
9745                         } else {
9746                                 long const val = fold_constant(end_range);
9747                                 statement->case_label.last_case = val;
9748
9749                                 if (warning.other && val < statement->case_label.first_case) {
9750                                         statement->case_label.is_empty_range = true;
9751                                         warningf(pos, "empty range specified");
9752                                 }
9753                         }
9754                 }
9755         }
9756
9757         PUSH_PARENT(statement);
9758
9759         expect(':', end_error);
9760 end_error:
9761
9762         if (current_switch != NULL) {
9763                 if (! statement->case_label.is_bad) {
9764                         /* Check for duplicate case values */
9765                         case_label_statement_t *c = &statement->case_label;
9766                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
9767                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
9768                                         continue;
9769
9770                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
9771                                         continue;
9772
9773                                 errorf(pos, "duplicate case value (previously used %P)",
9774                                        &l->base.source_position);
9775                                 break;
9776                         }
9777                 }
9778                 /* link all cases into the switch statement */
9779                 if (current_switch->last_case == NULL) {
9780                         current_switch->first_case      = &statement->case_label;
9781                 } else {
9782                         current_switch->last_case->next = &statement->case_label;
9783                 }
9784                 current_switch->last_case = &statement->case_label;
9785         } else {
9786                 errorf(pos, "case label not within a switch statement");
9787         }
9788
9789         statement_t *const inner_stmt = parse_statement();
9790         statement->case_label.statement = inner_stmt;
9791         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9792                 errorf(&inner_stmt->base.source_position, "declaration after case label");
9793         }
9794
9795         POP_PARENT;
9796         return statement;
9797 }
9798
9799 /**
9800  * Parse a default statement.
9801  */
9802 static statement_t *parse_default_statement(void)
9803 {
9804         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9805
9806         eat(T_default);
9807
9808         PUSH_PARENT(statement);
9809
9810         expect(':', end_error);
9811         if (current_switch != NULL) {
9812                 const case_label_statement_t *def_label = current_switch->default_label;
9813                 if (def_label != NULL) {
9814                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
9815                                &def_label->base.source_position);
9816                 } else {
9817                         current_switch->default_label = &statement->case_label;
9818
9819                         /* link all cases into the switch statement */
9820                         if (current_switch->last_case == NULL) {
9821                                 current_switch->first_case      = &statement->case_label;
9822                         } else {
9823                                 current_switch->last_case->next = &statement->case_label;
9824                         }
9825                         current_switch->last_case = &statement->case_label;
9826                 }
9827         } else {
9828                 errorf(&statement->base.source_position,
9829                         "'default' label not within a switch statement");
9830         }
9831
9832         statement_t *const inner_stmt = parse_statement();
9833         statement->case_label.statement = inner_stmt;
9834         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9835                 errorf(&inner_stmt->base.source_position, "declaration after default label");
9836         }
9837
9838         POP_PARENT;
9839         return statement;
9840 end_error:
9841         POP_PARENT;
9842         return create_invalid_statement();
9843 }
9844
9845 /**
9846  * Parse a label statement.
9847  */
9848 static statement_t *parse_label_statement(void)
9849 {
9850         assert(token.type == T_IDENTIFIER);
9851         symbol_t *symbol = token.v.symbol;
9852         label_t  *label  = get_label(symbol);
9853
9854         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
9855         statement->label.label       = label;
9856
9857         next_token();
9858
9859         PUSH_PARENT(statement);
9860
9861         /* if statement is already set then the label is defined twice,
9862          * otherwise it was just mentioned in a goto/local label declaration so far
9863          */
9864         if (label->statement != NULL) {
9865                 errorf(HERE, "duplicate label '%Y' (declared %P)",
9866                        symbol, &label->base.source_position);
9867         } else {
9868                 label->base.source_position = token.source_position;
9869                 label->statement            = statement;
9870         }
9871
9872         eat(':');
9873
9874         if (token.type == '}') {
9875                 /* TODO only warn? */
9876                 if (warning.other && false) {
9877                         warningf(HERE, "label at end of compound statement");
9878                         statement->label.statement = create_empty_statement();
9879                 } else {
9880                         errorf(HERE, "label at end of compound statement");
9881                         statement->label.statement = create_invalid_statement();
9882                 }
9883         } else if (token.type == ';') {
9884                 /* Eat an empty statement here, to avoid the warning about an empty
9885                  * statement after a label.  label:; is commonly used to have a label
9886                  * before a closing brace. */
9887                 statement->label.statement = create_empty_statement();
9888                 next_token();
9889         } else {
9890                 statement_t *const inner_stmt = parse_statement();
9891                 statement->label.statement = inner_stmt;
9892                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
9893                         errorf(&inner_stmt->base.source_position, "declaration after label");
9894                 }
9895         }
9896
9897         /* remember the labels in a list for later checking */
9898         *label_anchor = &statement->label;
9899         label_anchor  = &statement->label.next;
9900
9901         POP_PARENT;
9902         return statement;
9903 }
9904
9905 /**
9906  * Parse an if statement.
9907  */
9908 static statement_t *parse_if(void)
9909 {
9910         statement_t *statement = allocate_statement_zero(STATEMENT_IF);
9911
9912         eat(T_if);
9913
9914         PUSH_PARENT(statement);
9915
9916         add_anchor_token('{');
9917
9918         expect('(', end_error);
9919         add_anchor_token(')');
9920         expression_t *const expr = parse_expression();
9921         statement->ifs.condition = expr;
9922         /* §6.8.4.1:1  The controlling expression of an if statement shall have
9923          *             scalar type. */
9924         semantic_condition(expr, "condition of 'if'-statment");
9925         mark_vars_read(expr, NULL);
9926         rem_anchor_token(')');
9927         expect(')', end_error);
9928
9929 end_error:
9930         rem_anchor_token('{');
9931
9932         add_anchor_token(T_else);
9933         statement->ifs.true_statement = parse_statement();
9934         rem_anchor_token(T_else);
9935
9936         if (token.type == T_else) {
9937                 next_token();
9938                 statement->ifs.false_statement = parse_statement();
9939         }
9940
9941         POP_PARENT;
9942         return statement;
9943 }
9944
9945 /**
9946  * Check that all enums are handled in a switch.
9947  *
9948  * @param statement  the switch statement to check
9949  */
9950 static void check_enum_cases(const switch_statement_t *statement) {
9951         const type_t *type = skip_typeref(statement->expression->base.type);
9952         if (! is_type_enum(type))
9953                 return;
9954         const enum_type_t *enumt = &type->enumt;
9955
9956         /* if we have a default, no warnings */
9957         if (statement->default_label != NULL)
9958                 return;
9959
9960         /* FIXME: calculation of value should be done while parsing */
9961         /* TODO: quadratic algorithm here. Change to an n log n one */
9962         long            last_value = -1;
9963         const entity_t *entry      = enumt->enume->base.next;
9964         for (; entry != NULL && entry->kind == ENTITY_ENUM_VALUE;
9965              entry = entry->base.next) {
9966                 const expression_t *expression = entry->enum_value.value;
9967                 long                value      = expression != NULL ? fold_constant(expression) : last_value + 1;
9968                 bool                found      = false;
9969                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
9970                         if (l->expression == NULL)
9971                                 continue;
9972                         if (l->first_case <= value && value <= l->last_case) {
9973                                 found = true;
9974                                 break;
9975                         }
9976                 }
9977                 if (! found) {
9978                         warningf(&statement->base.source_position,
9979                                  "enumeration value '%Y' not handled in switch",
9980                                  entry->base.symbol);
9981                 }
9982                 last_value = value;
9983         }
9984 }
9985
9986 /**
9987  * Parse a switch statement.
9988  */
9989 static statement_t *parse_switch(void)
9990 {
9991         statement_t *statement = allocate_statement_zero(STATEMENT_SWITCH);
9992
9993         eat(T_switch);
9994
9995         PUSH_PARENT(statement);
9996
9997         expect('(', end_error);
9998         add_anchor_token(')');
9999         expression_t *const expr = parse_expression();
10000         mark_vars_read(expr, NULL);
10001         type_t       *      type = skip_typeref(expr->base.type);
10002         if (is_type_integer(type)) {
10003                 type = promote_integer(type);
10004                 if (warning.traditional) {
10005                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
10006                                 warningf(&expr->base.source_position,
10007                                         "'%T' switch expression not converted to '%T' in ISO C",
10008                                         type, type_int);
10009                         }
10010                 }
10011         } else if (is_type_valid(type)) {
10012                 errorf(&expr->base.source_position,
10013                        "switch quantity is not an integer, but '%T'", type);
10014                 type = type_error_type;
10015         }
10016         statement->switchs.expression = create_implicit_cast(expr, type);
10017         expect(')', end_error);
10018         rem_anchor_token(')');
10019
10020         switch_statement_t *rem = current_switch;
10021         current_switch          = &statement->switchs;
10022         statement->switchs.body = parse_statement();
10023         current_switch          = rem;
10024
10025         if (warning.switch_default &&
10026             statement->switchs.default_label == NULL) {
10027                 warningf(&statement->base.source_position, "switch has no default case");
10028         }
10029         if (warning.switch_enum)
10030                 check_enum_cases(&statement->switchs);
10031
10032         POP_PARENT;
10033         return statement;
10034 end_error:
10035         POP_PARENT;
10036         return create_invalid_statement();
10037 }
10038
10039 static statement_t *parse_loop_body(statement_t *const loop)
10040 {
10041         statement_t *const rem = current_loop;
10042         current_loop = loop;
10043
10044         statement_t *const body = parse_statement();
10045
10046         current_loop = rem;
10047         return body;
10048 }
10049
10050 /**
10051  * Parse a while statement.
10052  */
10053 static statement_t *parse_while(void)
10054 {
10055         statement_t *statement = allocate_statement_zero(STATEMENT_WHILE);
10056
10057         eat(T_while);
10058
10059         PUSH_PARENT(statement);
10060
10061         expect('(', end_error);
10062         add_anchor_token(')');
10063         expression_t *const cond = parse_expression();
10064         statement->whiles.condition = cond;
10065         /* §6.8.5:2    The controlling expression of an iteration statement shall
10066          *             have scalar type. */
10067         semantic_condition(cond, "condition of 'while'-statement");
10068         mark_vars_read(cond, NULL);
10069         rem_anchor_token(')');
10070         expect(')', end_error);
10071
10072         statement->whiles.body = parse_loop_body(statement);
10073
10074         POP_PARENT;
10075         return statement;
10076 end_error:
10077         POP_PARENT;
10078         return create_invalid_statement();
10079 }
10080
10081 /**
10082  * Parse a do statement.
10083  */
10084 static statement_t *parse_do(void)
10085 {
10086         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
10087
10088         eat(T_do);
10089
10090         PUSH_PARENT(statement);
10091
10092         add_anchor_token(T_while);
10093         statement->do_while.body = parse_loop_body(statement);
10094         rem_anchor_token(T_while);
10095
10096         expect(T_while, end_error);
10097         expect('(', end_error);
10098         add_anchor_token(')');
10099         expression_t *const cond = parse_expression();
10100         statement->do_while.condition = cond;
10101         /* §6.8.5:2    The controlling expression of an iteration statement shall
10102          *             have scalar type. */
10103         semantic_condition(cond, "condition of 'do-while'-statement");
10104         mark_vars_read(cond, NULL);
10105         rem_anchor_token(')');
10106         expect(')', end_error);
10107         expect(';', end_error);
10108
10109         POP_PARENT;
10110         return statement;
10111 end_error:
10112         POP_PARENT;
10113         return create_invalid_statement();
10114 }
10115
10116 /**
10117  * Parse a for statement.
10118  */
10119 static statement_t *parse_for(void)
10120 {
10121         statement_t *statement = allocate_statement_zero(STATEMENT_FOR);
10122
10123         eat(T_for);
10124
10125         expect('(', end_error1);
10126         add_anchor_token(')');
10127
10128         PUSH_PARENT(statement);
10129
10130         size_t const  top       = environment_top();
10131         scope_t      *old_scope = scope_push(&statement->fors.scope);
10132
10133         if (token.type == ';') {
10134                 next_token();
10135         } else if (is_declaration_specifier(&token, false)) {
10136                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10137         } else {
10138                 add_anchor_token(';');
10139                 expression_t *const init = parse_expression();
10140                 statement->fors.initialisation = init;
10141                 mark_vars_read(init, ENT_ANY);
10142                 if (warning.unused_value && !expression_has_effect(init)) {
10143                         warningf(&init->base.source_position,
10144                                         "initialisation of 'for'-statement has no effect");
10145                 }
10146                 rem_anchor_token(';');
10147                 expect(';', end_error2);
10148         }
10149
10150         if (token.type != ';') {
10151                 add_anchor_token(';');
10152                 expression_t *const cond = parse_expression();
10153                 statement->fors.condition = cond;
10154                 /* §6.8.5:2    The controlling expression of an iteration statement
10155                  *             shall have scalar type. */
10156                 semantic_condition(cond, "condition of 'for'-statement");
10157                 mark_vars_read(cond, NULL);
10158                 rem_anchor_token(';');
10159         }
10160         expect(';', end_error2);
10161         if (token.type != ')') {
10162                 expression_t *const step = parse_expression();
10163                 statement->fors.step = step;
10164                 mark_vars_read(step, ENT_ANY);
10165                 if (warning.unused_value && !expression_has_effect(step)) {
10166                         warningf(&step->base.source_position,
10167                                  "step of 'for'-statement has no effect");
10168                 }
10169         }
10170         expect(')', end_error2);
10171         rem_anchor_token(')');
10172         statement->fors.body = parse_loop_body(statement);
10173
10174         assert(current_scope == &statement->fors.scope);
10175         scope_pop(old_scope);
10176         environment_pop_to(top);
10177
10178         POP_PARENT;
10179         return statement;
10180
10181 end_error2:
10182         POP_PARENT;
10183         rem_anchor_token(')');
10184         assert(current_scope == &statement->fors.scope);
10185         scope_pop(old_scope);
10186         environment_pop_to(top);
10187         /* fallthrough */
10188
10189 end_error1:
10190         return create_invalid_statement();
10191 }
10192
10193 /**
10194  * Parse a goto statement.
10195  */
10196 static statement_t *parse_goto(void)
10197 {
10198         statement_t *statement = allocate_statement_zero(STATEMENT_GOTO);
10199         eat(T_goto);
10200
10201         if (GNU_MODE && token.type == '*') {
10202                 next_token();
10203                 expression_t *expression = parse_expression();
10204                 mark_vars_read(expression, NULL);
10205
10206                 /* Argh: although documentation says the expression must be of type void*,
10207                  * gcc accepts anything that can be casted into void* without error */
10208                 type_t *type = expression->base.type;
10209
10210                 if (type != type_error_type) {
10211                         if (!is_type_pointer(type) && !is_type_integer(type)) {
10212                                 errorf(&expression->base.source_position,
10213                                         "cannot convert to a pointer type");
10214                         } else if (warning.other && type != type_void_ptr) {
10215                                 warningf(&expression->base.source_position,
10216                                         "type of computed goto expression should be 'void*' not '%T'", type);
10217                         }
10218                         expression = create_implicit_cast(expression, type_void_ptr);
10219                 }
10220
10221                 statement->gotos.expression = expression;
10222         } else {
10223                 if (token.type != T_IDENTIFIER) {
10224                         if (GNU_MODE)
10225                                 parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
10226                         else
10227                                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
10228                         eat_until_anchor();
10229                         goto end_error;
10230                 }
10231                 symbol_t *symbol = token.v.symbol;
10232                 next_token();
10233
10234                 statement->gotos.label = get_label(symbol);
10235         }
10236
10237         /* remember the goto's in a list for later checking */
10238         *goto_anchor = &statement->gotos;
10239         goto_anchor  = &statement->gotos.next;
10240
10241         expect(';', end_error);
10242
10243         return statement;
10244 end_error:
10245         return create_invalid_statement();
10246 }
10247
10248 /**
10249  * Parse a continue statement.
10250  */
10251 static statement_t *parse_continue(void)
10252 {
10253         if (current_loop == NULL) {
10254                 errorf(HERE, "continue statement not within loop");
10255         }
10256
10257         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
10258
10259         eat(T_continue);
10260         expect(';', end_error);
10261
10262 end_error:
10263         return statement;
10264 }
10265
10266 /**
10267  * Parse a break statement.
10268  */
10269 static statement_t *parse_break(void)
10270 {
10271         if (current_switch == NULL && current_loop == NULL) {
10272                 errorf(HERE, "break statement not within loop or switch");
10273         }
10274
10275         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
10276
10277         eat(T_break);
10278         expect(';', end_error);
10279
10280 end_error:
10281         return statement;
10282 }
10283
10284 /**
10285  * Parse a __leave statement.
10286  */
10287 static statement_t *parse_leave_statement(void)
10288 {
10289         if (current_try == NULL) {
10290                 errorf(HERE, "__leave statement not within __try");
10291         }
10292
10293         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
10294
10295         eat(T___leave);
10296         expect(';', end_error);
10297
10298 end_error:
10299         return statement;
10300 }
10301
10302 /**
10303  * Check if a given entity represents a local variable.
10304  */
10305 static bool is_local_variable(const entity_t *entity)
10306 {
10307         if (entity->kind != ENTITY_VARIABLE)
10308                 return false;
10309
10310         switch ((storage_class_tag_t) entity->declaration.storage_class) {
10311         case STORAGE_CLASS_AUTO:
10312         case STORAGE_CLASS_REGISTER: {
10313                 const type_t *type = skip_typeref(entity->declaration.type);
10314                 if (is_type_function(type)) {
10315                         return false;
10316                 } else {
10317                         return true;
10318                 }
10319         }
10320         default:
10321                 return false;
10322         }
10323 }
10324
10325 /**
10326  * Check if a given expression represents a local variable.
10327  */
10328 static bool expression_is_local_variable(const expression_t *expression)
10329 {
10330         if (expression->base.kind != EXPR_REFERENCE) {
10331                 return false;
10332         }
10333         const entity_t *entity = expression->reference.entity;
10334         return is_local_variable(entity);
10335 }
10336
10337 /**
10338  * Check if a given expression represents a local variable and
10339  * return its declaration then, else return NULL.
10340  */
10341 entity_t *expression_is_variable(const expression_t *expression)
10342 {
10343         if (expression->base.kind != EXPR_REFERENCE) {
10344                 return NULL;
10345         }
10346         entity_t *entity = expression->reference.entity;
10347         if (entity->kind != ENTITY_VARIABLE)
10348                 return NULL;
10349
10350         return entity;
10351 }
10352
10353 /**
10354  * Parse a return statement.
10355  */
10356 static statement_t *parse_return(void)
10357 {
10358         eat(T_return);
10359
10360         statement_t *statement = allocate_statement_zero(STATEMENT_RETURN);
10361
10362         expression_t *return_value = NULL;
10363         if (token.type != ';') {
10364                 return_value = parse_expression();
10365                 mark_vars_read(return_value, NULL);
10366         }
10367
10368         const type_t *const func_type = skip_typeref(current_function->base.type);
10369         assert(is_type_function(func_type));
10370         type_t *const return_type = skip_typeref(func_type->function.return_type);
10371
10372         if (return_value != NULL) {
10373                 type_t *return_value_type = skip_typeref(return_value->base.type);
10374
10375                 if (is_type_atomic(return_type,        ATOMIC_TYPE_VOID) &&
10376                                 !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
10377                         if (warning.other) {
10378                                 warningf(&statement->base.source_position,
10379                                                 "'return' with a value, in function returning void");
10380                         }
10381                         return_value = NULL;
10382                 } else {
10383                         assign_error_t error = semantic_assign(return_type, return_value);
10384                         report_assign_error(error, return_type, return_value, "'return'",
10385                                             &statement->base.source_position);
10386                         return_value = create_implicit_cast(return_value, return_type);
10387                 }
10388                 /* check for returning address of a local var */
10389                 if (warning.other && return_value != NULL
10390                                 && return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
10391                         const expression_t *expression = return_value->unary.value;
10392                         if (expression_is_local_variable(expression)) {
10393                                 warningf(&statement->base.source_position,
10394                                          "function returns address of local variable");
10395                         }
10396                 }
10397         } else if (warning.other && !is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10398                 warningf(&statement->base.source_position,
10399                                 "'return' without value, in function returning non-void");
10400         }
10401         statement->returns.value = return_value;
10402
10403         expect(';', end_error);
10404
10405 end_error:
10406         return statement;
10407 }
10408
10409 /**
10410  * Parse a declaration statement.
10411  */
10412 static statement_t *parse_declaration_statement(void)
10413 {
10414         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10415
10416         entity_t *before = current_scope->last_entity;
10417         if (GNU_MODE) {
10418                 parse_external_declaration();
10419         } else {
10420                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10421         }
10422
10423         if (before == NULL) {
10424                 statement->declaration.declarations_begin = current_scope->entities;
10425         } else {
10426                 statement->declaration.declarations_begin = before->base.next;
10427         }
10428         statement->declaration.declarations_end = current_scope->last_entity;
10429
10430         return statement;
10431 }
10432
10433 /**
10434  * Parse an expression statement, ie. expr ';'.
10435  */
10436 static statement_t *parse_expression_statement(void)
10437 {
10438         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10439
10440         expression_t *const expr         = parse_expression();
10441         statement->expression.expression = expr;
10442         mark_vars_read(expr, ENT_ANY);
10443
10444         expect(';', end_error);
10445
10446 end_error:
10447         return statement;
10448 }
10449
10450 /**
10451  * Parse a microsoft __try { } __finally { } or
10452  * __try{ } __except() { }
10453  */
10454 static statement_t *parse_ms_try_statment(void)
10455 {
10456         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
10457         eat(T___try);
10458
10459         PUSH_PARENT(statement);
10460
10461         ms_try_statement_t *rem = current_try;
10462         current_try = &statement->ms_try;
10463         statement->ms_try.try_statement = parse_compound_statement(false);
10464         current_try = rem;
10465
10466         POP_PARENT;
10467
10468         if (token.type == T___except) {
10469                 eat(T___except);
10470                 expect('(', end_error);
10471                 add_anchor_token(')');
10472                 expression_t *const expr = parse_expression();
10473                 mark_vars_read(expr, NULL);
10474                 type_t       *      type = skip_typeref(expr->base.type);
10475                 if (is_type_integer(type)) {
10476                         type = promote_integer(type);
10477                 } else if (is_type_valid(type)) {
10478                         errorf(&expr->base.source_position,
10479                                "__expect expression is not an integer, but '%T'", type);
10480                         type = type_error_type;
10481                 }
10482                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
10483                 rem_anchor_token(')');
10484                 expect(')', end_error);
10485                 statement->ms_try.final_statement = parse_compound_statement(false);
10486         } else if (token.type == T__finally) {
10487                 eat(T___finally);
10488                 statement->ms_try.final_statement = parse_compound_statement(false);
10489         } else {
10490                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
10491                 return create_invalid_statement();
10492         }
10493         return statement;
10494 end_error:
10495         return create_invalid_statement();
10496 }
10497
10498 static statement_t *parse_empty_statement(void)
10499 {
10500         if (warning.empty_statement) {
10501                 warningf(HERE, "statement is empty");
10502         }
10503         statement_t *const statement = create_empty_statement();
10504         eat(';');
10505         return statement;
10506 }
10507
10508 static statement_t *parse_local_label_declaration(void)
10509 {
10510         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10511
10512         eat(T___label__);
10513
10514         entity_t *begin = NULL, *end = NULL;
10515
10516         while (true) {
10517                 if (token.type != T_IDENTIFIER) {
10518                         parse_error_expected("while parsing local label declaration",
10519                                 T_IDENTIFIER, NULL);
10520                         goto end_error;
10521                 }
10522                 symbol_t *symbol = token.v.symbol;
10523                 entity_t *entity = get_entity(symbol, NAMESPACE_LABEL);
10524                 if (entity != NULL && entity->base.parent_scope == current_scope) {
10525                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition %P)",
10526                                symbol, &entity->base.source_position);
10527                 } else {
10528                         entity = allocate_entity_zero(ENTITY_LOCAL_LABEL);
10529
10530                         entity->base.parent_scope    = current_scope;
10531                         entity->base.namespc         = NAMESPACE_LABEL;
10532                         entity->base.source_position = token.source_position;
10533                         entity->base.symbol          = symbol;
10534
10535                         if (end != NULL)
10536                                 end->base.next = entity;
10537                         end = entity;
10538                         if (begin == NULL)
10539                                 begin = entity;
10540
10541                         environment_push(entity);
10542                 }
10543                 next_token();
10544
10545                 if (token.type != ',')
10546                         break;
10547                 next_token();
10548         }
10549         eat(';');
10550 end_error:
10551         statement->declaration.declarations_begin = begin;
10552         statement->declaration.declarations_end   = end;
10553         return statement;
10554 }
10555
10556 static void parse_namespace_definition(void)
10557 {
10558         eat(T_namespace);
10559
10560         entity_t *entity = NULL;
10561         symbol_t *symbol = NULL;
10562
10563         if (token.type == T_IDENTIFIER) {
10564                 symbol = token.v.symbol;
10565                 next_token();
10566
10567                 entity = get_entity(symbol, NAMESPACE_NORMAL);
10568                 if (entity != NULL && entity->kind != ENTITY_NAMESPACE
10569                                 && entity->base.parent_scope == current_scope) {
10570                         error_redefined_as_different_kind(&token.source_position,
10571                                                           entity, ENTITY_NAMESPACE);
10572                         entity = NULL;
10573                 }
10574         }
10575
10576         if (entity == NULL) {
10577                 entity                       = allocate_entity_zero(ENTITY_NAMESPACE);
10578                 entity->base.symbol          = symbol;
10579                 entity->base.source_position = token.source_position;
10580                 entity->base.namespc         = NAMESPACE_NORMAL;
10581                 entity->base.parent_scope    = current_scope;
10582         }
10583
10584         if (token.type == '=') {
10585                 /* TODO: parse namespace alias */
10586                 panic("namespace alias definition not supported yet");
10587         }
10588
10589         environment_push(entity);
10590         append_entity(current_scope, entity);
10591
10592         size_t const  top       = environment_top();
10593         scope_t      *old_scope = scope_push(&entity->namespacee.members);
10594
10595         expect('{', end_error);
10596         parse_externals();
10597         expect('}', end_error);
10598
10599 end_error:
10600         assert(current_scope == &entity->namespacee.members);
10601         scope_pop(old_scope);
10602         environment_pop_to(top);
10603 }
10604
10605 /**
10606  * Parse a statement.
10607  * There's also parse_statement() which additionally checks for
10608  * "statement has no effect" warnings
10609  */
10610 static statement_t *intern_parse_statement(void)
10611 {
10612         statement_t *statement = NULL;
10613
10614         /* declaration or statement */
10615         add_anchor_token(';');
10616         switch (token.type) {
10617         case T_IDENTIFIER: {
10618                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
10619                 if (la1_type == ':') {
10620                         statement = parse_label_statement();
10621                 } else if (is_typedef_symbol(token.v.symbol)) {
10622                         statement = parse_declaration_statement();
10623                 } else {
10624                         /* it's an identifier, the grammar says this must be an
10625                          * expression statement. However it is common that users mistype
10626                          * declaration types, so we guess a bit here to improve robustness
10627                          * for incorrect programs */
10628                         switch (la1_type) {
10629                         case '&':
10630                         case '*':
10631                                 if (get_entity(token.v.symbol, NAMESPACE_NORMAL) != NULL)
10632                                         goto expression_statment;
10633                                 /* FALLTHROUGH */
10634
10635                         DECLARATION_START
10636                         case T_IDENTIFIER:
10637                                 statement = parse_declaration_statement();
10638                                 break;
10639
10640                         default:
10641 expression_statment:
10642                                 statement = parse_expression_statement();
10643                                 break;
10644                         }
10645                 }
10646                 break;
10647         }
10648
10649         case T___extension__:
10650                 /* This can be a prefix to a declaration or an expression statement.
10651                  * We simply eat it now and parse the rest with tail recursion. */
10652                 do {
10653                         next_token();
10654                 } while (token.type == T___extension__);
10655                 bool old_gcc_extension = in_gcc_extension;
10656                 in_gcc_extension       = true;
10657                 statement = intern_parse_statement();
10658                 in_gcc_extension = old_gcc_extension;
10659                 break;
10660
10661         DECLARATION_START
10662                 statement = parse_declaration_statement();
10663                 break;
10664
10665         case T___label__:
10666                 statement = parse_local_label_declaration();
10667                 break;
10668
10669         case ';':         statement = parse_empty_statement();         break;
10670         case '{':         statement = parse_compound_statement(false); break;
10671         case T___leave:   statement = parse_leave_statement();         break;
10672         case T___try:     statement = parse_ms_try_statment();         break;
10673         case T_asm:       statement = parse_asm_statement();           break;
10674         case T_break:     statement = parse_break();                   break;
10675         case T_case:      statement = parse_case_statement();          break;
10676         case T_continue:  statement = parse_continue();                break;
10677         case T_default:   statement = parse_default_statement();       break;
10678         case T_do:        statement = parse_do();                      break;
10679         case T_for:       statement = parse_for();                     break;
10680         case T_goto:      statement = parse_goto();                    break;
10681         case T_if:        statement = parse_if();                      break;
10682         case T_return:    statement = parse_return();                  break;
10683         case T_switch:    statement = parse_switch();                  break;
10684         case T_while:     statement = parse_while();                   break;
10685
10686         EXPRESSION_START
10687                 statement = parse_expression_statement();
10688                 break;
10689
10690         default:
10691                 errorf(HERE, "unexpected token %K while parsing statement", &token);
10692                 statement = create_invalid_statement();
10693                 if (!at_anchor())
10694                         next_token();
10695                 break;
10696         }
10697         rem_anchor_token(';');
10698
10699         assert(statement != NULL
10700                         && statement->base.source_position.input_name != NULL);
10701
10702         return statement;
10703 }
10704
10705 /**
10706  * parse a statement and emits "statement has no effect" warning if needed
10707  * (This is really a wrapper around intern_parse_statement with check for 1
10708  *  single warning. It is needed, because for statement expressions we have
10709  *  to avoid the warning on the last statement)
10710  */
10711 static statement_t *parse_statement(void)
10712 {
10713         statement_t *statement = intern_parse_statement();
10714
10715         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
10716                 expression_t *expression = statement->expression.expression;
10717                 if (!expression_has_effect(expression)) {
10718                         warningf(&expression->base.source_position,
10719                                         "statement has no effect");
10720                 }
10721         }
10722
10723         return statement;
10724 }
10725
10726 /**
10727  * Parse a compound statement.
10728  */
10729 static statement_t *parse_compound_statement(bool inside_expression_statement)
10730 {
10731         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
10732
10733         PUSH_PARENT(statement);
10734
10735         eat('{');
10736         add_anchor_token('}');
10737         /* tokens, which can start a statement */
10738         /* TODO MS, __builtin_FOO */
10739         add_anchor_token('!');
10740         add_anchor_token('&');
10741         add_anchor_token('(');
10742         add_anchor_token('*');
10743         add_anchor_token('+');
10744         add_anchor_token('-');
10745         add_anchor_token('{');
10746         add_anchor_token('~');
10747         add_anchor_token(T_CHARACTER_CONSTANT);
10748         add_anchor_token(T_COLONCOLON);
10749         add_anchor_token(T_FLOATINGPOINT);
10750         add_anchor_token(T_IDENTIFIER);
10751         add_anchor_token(T_INTEGER);
10752         add_anchor_token(T_MINUSMINUS);
10753         add_anchor_token(T_PLUSPLUS);
10754         add_anchor_token(T_STRING_LITERAL);
10755         add_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10756         add_anchor_token(T_WIDE_STRING_LITERAL);
10757         add_anchor_token(T__Bool);
10758         add_anchor_token(T__Complex);
10759         add_anchor_token(T__Imaginary);
10760         add_anchor_token(T___FUNCTION__);
10761         add_anchor_token(T___PRETTY_FUNCTION__);
10762         add_anchor_token(T___alignof__);
10763         add_anchor_token(T___attribute__);
10764         add_anchor_token(T___builtin_va_start);
10765         add_anchor_token(T___extension__);
10766         add_anchor_token(T___func__);
10767         add_anchor_token(T___imag__);
10768         add_anchor_token(T___label__);
10769         add_anchor_token(T___real__);
10770         add_anchor_token(T___thread);
10771         add_anchor_token(T_asm);
10772         add_anchor_token(T_auto);
10773         add_anchor_token(T_bool);
10774         add_anchor_token(T_break);
10775         add_anchor_token(T_case);
10776         add_anchor_token(T_char);
10777         add_anchor_token(T_class);
10778         add_anchor_token(T_const);
10779         add_anchor_token(T_const_cast);
10780         add_anchor_token(T_continue);
10781         add_anchor_token(T_default);
10782         add_anchor_token(T_delete);
10783         add_anchor_token(T_double);
10784         add_anchor_token(T_do);
10785         add_anchor_token(T_dynamic_cast);
10786         add_anchor_token(T_enum);
10787         add_anchor_token(T_extern);
10788         add_anchor_token(T_false);
10789         add_anchor_token(T_float);
10790         add_anchor_token(T_for);
10791         add_anchor_token(T_goto);
10792         add_anchor_token(T_if);
10793         add_anchor_token(T_inline);
10794         add_anchor_token(T_int);
10795         add_anchor_token(T_long);
10796         add_anchor_token(T_new);
10797         add_anchor_token(T_operator);
10798         add_anchor_token(T_register);
10799         add_anchor_token(T_reinterpret_cast);
10800         add_anchor_token(T_restrict);
10801         add_anchor_token(T_return);
10802         add_anchor_token(T_short);
10803         add_anchor_token(T_signed);
10804         add_anchor_token(T_sizeof);
10805         add_anchor_token(T_static);
10806         add_anchor_token(T_static_cast);
10807         add_anchor_token(T_struct);
10808         add_anchor_token(T_switch);
10809         add_anchor_token(T_template);
10810         add_anchor_token(T_this);
10811         add_anchor_token(T_throw);
10812         add_anchor_token(T_true);
10813         add_anchor_token(T_try);
10814         add_anchor_token(T_typedef);
10815         add_anchor_token(T_typeid);
10816         add_anchor_token(T_typename);
10817         add_anchor_token(T_typeof);
10818         add_anchor_token(T_union);
10819         add_anchor_token(T_unsigned);
10820         add_anchor_token(T_using);
10821         add_anchor_token(T_void);
10822         add_anchor_token(T_volatile);
10823         add_anchor_token(T_wchar_t);
10824         add_anchor_token(T_while);
10825
10826         size_t const  top       = environment_top();
10827         scope_t      *old_scope = scope_push(&statement->compound.scope);
10828
10829         statement_t **anchor            = &statement->compound.statements;
10830         bool          only_decls_so_far = true;
10831         while (token.type != '}') {
10832                 if (token.type == T_EOF) {
10833                         errorf(&statement->base.source_position,
10834                                "EOF while parsing compound statement");
10835                         break;
10836                 }
10837                 statement_t *sub_statement = intern_parse_statement();
10838                 if (is_invalid_statement(sub_statement)) {
10839                         /* an error occurred. if we are at an anchor, return */
10840                         if (at_anchor())
10841                                 goto end_error;
10842                         continue;
10843                 }
10844
10845                 if (warning.declaration_after_statement) {
10846                         if (sub_statement->kind != STATEMENT_DECLARATION) {
10847                                 only_decls_so_far = false;
10848                         } else if (!only_decls_so_far) {
10849                                 warningf(&sub_statement->base.source_position,
10850                                          "ISO C90 forbids mixed declarations and code");
10851                         }
10852                 }
10853
10854                 *anchor = sub_statement;
10855
10856                 while (sub_statement->base.next != NULL)
10857                         sub_statement = sub_statement->base.next;
10858
10859                 anchor = &sub_statement->base.next;
10860         }
10861         next_token();
10862
10863         /* look over all statements again to produce no effect warnings */
10864         if (warning.unused_value) {
10865                 statement_t *sub_statement = statement->compound.statements;
10866                 for (; sub_statement != NULL; sub_statement = sub_statement->base.next) {
10867                         if (sub_statement->kind != STATEMENT_EXPRESSION)
10868                                 continue;
10869                         /* don't emit a warning for the last expression in an expression
10870                          * statement as it has always an effect */
10871                         if (inside_expression_statement && sub_statement->base.next == NULL)
10872                                 continue;
10873
10874                         expression_t *expression = sub_statement->expression.expression;
10875                         if (!expression_has_effect(expression)) {
10876                                 warningf(&expression->base.source_position,
10877                                          "statement has no effect");
10878                         }
10879                 }
10880         }
10881
10882 end_error:
10883         rem_anchor_token(T_while);
10884         rem_anchor_token(T_wchar_t);
10885         rem_anchor_token(T_volatile);
10886         rem_anchor_token(T_void);
10887         rem_anchor_token(T_using);
10888         rem_anchor_token(T_unsigned);
10889         rem_anchor_token(T_union);
10890         rem_anchor_token(T_typeof);
10891         rem_anchor_token(T_typename);
10892         rem_anchor_token(T_typeid);
10893         rem_anchor_token(T_typedef);
10894         rem_anchor_token(T_try);
10895         rem_anchor_token(T_true);
10896         rem_anchor_token(T_throw);
10897         rem_anchor_token(T_this);
10898         rem_anchor_token(T_template);
10899         rem_anchor_token(T_switch);
10900         rem_anchor_token(T_struct);
10901         rem_anchor_token(T_static_cast);
10902         rem_anchor_token(T_static);
10903         rem_anchor_token(T_sizeof);
10904         rem_anchor_token(T_signed);
10905         rem_anchor_token(T_short);
10906         rem_anchor_token(T_return);
10907         rem_anchor_token(T_restrict);
10908         rem_anchor_token(T_reinterpret_cast);
10909         rem_anchor_token(T_register);
10910         rem_anchor_token(T_operator);
10911         rem_anchor_token(T_new);
10912         rem_anchor_token(T_long);
10913         rem_anchor_token(T_int);
10914         rem_anchor_token(T_inline);
10915         rem_anchor_token(T_if);
10916         rem_anchor_token(T_goto);
10917         rem_anchor_token(T_for);
10918         rem_anchor_token(T_float);
10919         rem_anchor_token(T_false);
10920         rem_anchor_token(T_extern);
10921         rem_anchor_token(T_enum);
10922         rem_anchor_token(T_dynamic_cast);
10923         rem_anchor_token(T_do);
10924         rem_anchor_token(T_double);
10925         rem_anchor_token(T_delete);
10926         rem_anchor_token(T_default);
10927         rem_anchor_token(T_continue);
10928         rem_anchor_token(T_const_cast);
10929         rem_anchor_token(T_const);
10930         rem_anchor_token(T_class);
10931         rem_anchor_token(T_char);
10932         rem_anchor_token(T_case);
10933         rem_anchor_token(T_break);
10934         rem_anchor_token(T_bool);
10935         rem_anchor_token(T_auto);
10936         rem_anchor_token(T_asm);
10937         rem_anchor_token(T___thread);
10938         rem_anchor_token(T___real__);
10939         rem_anchor_token(T___label__);
10940         rem_anchor_token(T___imag__);
10941         rem_anchor_token(T___func__);
10942         rem_anchor_token(T___extension__);
10943         rem_anchor_token(T___builtin_va_start);
10944         rem_anchor_token(T___attribute__);
10945         rem_anchor_token(T___alignof__);
10946         rem_anchor_token(T___PRETTY_FUNCTION__);
10947         rem_anchor_token(T___FUNCTION__);
10948         rem_anchor_token(T__Imaginary);
10949         rem_anchor_token(T__Complex);
10950         rem_anchor_token(T__Bool);
10951         rem_anchor_token(T_WIDE_STRING_LITERAL);
10952         rem_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10953         rem_anchor_token(T_STRING_LITERAL);
10954         rem_anchor_token(T_PLUSPLUS);
10955         rem_anchor_token(T_MINUSMINUS);
10956         rem_anchor_token(T_INTEGER);
10957         rem_anchor_token(T_IDENTIFIER);
10958         rem_anchor_token(T_FLOATINGPOINT);
10959         rem_anchor_token(T_COLONCOLON);
10960         rem_anchor_token(T_CHARACTER_CONSTANT);
10961         rem_anchor_token('~');
10962         rem_anchor_token('{');
10963         rem_anchor_token('-');
10964         rem_anchor_token('+');
10965         rem_anchor_token('*');
10966         rem_anchor_token('(');
10967         rem_anchor_token('&');
10968         rem_anchor_token('!');
10969         rem_anchor_token('}');
10970         assert(current_scope == &statement->compound.scope);
10971         scope_pop(old_scope);
10972         environment_pop_to(top);
10973
10974         POP_PARENT;
10975         return statement;
10976 }
10977
10978 /**
10979  * Check for unused global static functions and variables
10980  */
10981 static void check_unused_globals(void)
10982 {
10983         if (!warning.unused_function && !warning.unused_variable)
10984                 return;
10985
10986         for (const entity_t *entity = file_scope->entities; entity != NULL;
10987              entity = entity->base.next) {
10988                 if (!is_declaration(entity))
10989                         continue;
10990
10991                 const declaration_t *declaration = &entity->declaration;
10992                 if (declaration->used                  ||
10993                     declaration->modifiers & DM_UNUSED ||
10994                     declaration->modifiers & DM_USED   ||
10995                     declaration->storage_class != STORAGE_CLASS_STATIC)
10996                         continue;
10997
10998                 type_t *const type = declaration->type;
10999                 const char *s;
11000                 if (entity->kind == ENTITY_FUNCTION) {
11001                         /* inhibit warning for static inline functions */
11002                         if (entity->function.is_inline)
11003                                 continue;
11004
11005                         s = entity->function.statement != NULL ? "defined" : "declared";
11006                 } else {
11007                         s = "defined";
11008                 }
11009
11010                 warningf(&declaration->base.source_position, "'%#T' %s but not used",
11011                         type, declaration->base.symbol, s);
11012         }
11013 }
11014
11015 static void parse_global_asm(void)
11016 {
11017         statement_t *statement = allocate_statement_zero(STATEMENT_ASM);
11018
11019         eat(T_asm);
11020         expect('(', end_error);
11021
11022         statement->asms.asm_text = parse_string_literals();
11023         statement->base.next     = unit->global_asm;
11024         unit->global_asm         = statement;
11025
11026         expect(')', end_error);
11027         expect(';', end_error);
11028
11029 end_error:;
11030 }
11031
11032 static void parse_linkage_specification(void)
11033 {
11034         eat(T_extern);
11035         assert(token.type == T_STRING_LITERAL);
11036
11037         const char *linkage = parse_string_literals().begin;
11038
11039         linkage_kind_t old_linkage = current_linkage;
11040         linkage_kind_t new_linkage;
11041         if (strcmp(linkage, "C") == 0) {
11042                 new_linkage = LINKAGE_C;
11043         } else if (strcmp(linkage, "C++") == 0) {
11044                 new_linkage = LINKAGE_CXX;
11045         } else {
11046                 errorf(HERE, "linkage string \"%s\" not recognized", linkage);
11047                 new_linkage = LINKAGE_INVALID;
11048         }
11049         current_linkage = new_linkage;
11050
11051         if (token.type == '{') {
11052                 next_token();
11053                 parse_externals();
11054                 expect('}', end_error);
11055         } else {
11056                 parse_external();
11057         }
11058
11059 end_error:
11060         assert(current_linkage == new_linkage);
11061         current_linkage = old_linkage;
11062 }
11063
11064 static void parse_external(void)
11065 {
11066         switch (token.type) {
11067                 DECLARATION_START_NO_EXTERN
11068                 case T_IDENTIFIER:
11069                 case T___extension__:
11070                 /* tokens below are for implicit int */
11071                 case '&': /* & x; -> int& x; (and error later, because C++ has no
11072                              implicit int) */
11073                 case '*': /* * x; -> int* x; */
11074                 case '(': /* (x); -> int (x); */
11075                         parse_external_declaration();
11076                         return;
11077
11078                 case T_extern:
11079                         if (look_ahead(1)->type == T_STRING_LITERAL) {
11080                                 parse_linkage_specification();
11081                         } else {
11082                                 parse_external_declaration();
11083                         }
11084                         return;
11085
11086                 case T_asm:
11087                         parse_global_asm();
11088                         return;
11089
11090                 case T_namespace:
11091                         parse_namespace_definition();
11092                         return;
11093
11094                 case ';':
11095                         if (!strict_mode) {
11096                                 if (warning.other)
11097                                         warningf(HERE, "stray ';' outside of function");
11098                                 next_token();
11099                                 return;
11100                         }
11101                         /* FALLTHROUGH */
11102
11103                 default:
11104                         errorf(HERE, "stray %K outside of function", &token);
11105                         if (token.type == '(' || token.type == '{' || token.type == '[')
11106                                 eat_until_matching_token(token.type);
11107                         next_token();
11108                         return;
11109         }
11110 }
11111
11112 static void parse_externals(void)
11113 {
11114         add_anchor_token('}');
11115         add_anchor_token(T_EOF);
11116
11117 #ifndef NDEBUG
11118         unsigned char token_anchor_copy[T_LAST_TOKEN];
11119         memcpy(token_anchor_copy, token_anchor_set, sizeof(token_anchor_copy));
11120 #endif
11121
11122         while (token.type != T_EOF && token.type != '}') {
11123 #ifndef NDEBUG
11124                 bool anchor_leak = false;
11125                 for (int i = 0; i != T_LAST_TOKEN; ++i) {
11126                         unsigned char count = token_anchor_set[i] - token_anchor_copy[i];
11127                         if (count != 0) {
11128                                 errorf(HERE, "Leaked anchor token %k %d times", i, count);
11129                                 anchor_leak = true;
11130                         }
11131                 }
11132                 if (in_gcc_extension) {
11133                         errorf(HERE, "Leaked __extension__");
11134                         anchor_leak = true;
11135                 }
11136
11137                 if (anchor_leak)
11138                         abort();
11139 #endif
11140
11141                 parse_external();
11142         }
11143
11144         rem_anchor_token(T_EOF);
11145         rem_anchor_token('}');
11146 }
11147
11148 /**
11149  * Parse a translation unit.
11150  */
11151 static void parse_translation_unit(void)
11152 {
11153         add_anchor_token(T_EOF);
11154
11155         while (true) {
11156                 parse_externals();
11157
11158                 if (token.type == T_EOF)
11159                         break;
11160
11161                 errorf(HERE, "stray %K outside of function", &token);
11162                 if (token.type == '(' || token.type == '{' || token.type == '[')
11163                         eat_until_matching_token(token.type);
11164                 next_token();
11165         }
11166 }
11167
11168 /**
11169  * Parse the input.
11170  *
11171  * @return  the translation unit or NULL if errors occurred.
11172  */
11173 void start_parsing(void)
11174 {
11175         environment_stack = NEW_ARR_F(stack_entry_t, 0);
11176         label_stack       = NEW_ARR_F(stack_entry_t, 0);
11177         diagnostic_count  = 0;
11178         error_count       = 0;
11179         warning_count     = 0;
11180
11181         type_set_output(stderr);
11182         ast_set_output(stderr);
11183
11184         assert(unit == NULL);
11185         unit = allocate_ast_zero(sizeof(unit[0]));
11186
11187         assert(file_scope == NULL);
11188         file_scope = &unit->scope;
11189
11190         assert(current_scope == NULL);
11191         scope_push(&unit->scope);
11192 }
11193
11194 translation_unit_t *finish_parsing(void)
11195 {
11196         assert(current_scope == &unit->scope);
11197         scope_pop(NULL);
11198
11199         assert(file_scope == &unit->scope);
11200         check_unused_globals();
11201         file_scope = NULL;
11202
11203         DEL_ARR_F(environment_stack);
11204         DEL_ARR_F(label_stack);
11205
11206         translation_unit_t *result = unit;
11207         unit = NULL;
11208         return result;
11209 }
11210
11211 /* GCC allows global arrays without size and assigns them a length of one,
11212  * if no different declaration follows */
11213 static void complete_incomplete_arrays(void)
11214 {
11215         size_t n = ARR_LEN(incomplete_arrays);
11216         for (size_t i = 0; i != n; ++i) {
11217                 declaration_t *const decl      = incomplete_arrays[i];
11218                 type_t        *const orig_type = decl->type;
11219                 type_t        *const type      = skip_typeref(orig_type);
11220
11221                 if (!is_type_incomplete(type))
11222                         continue;
11223
11224                 if (warning.other) {
11225                         warningf(&decl->base.source_position,
11226                                         "array '%#T' assumed to have one element",
11227                                         orig_type, decl->base.symbol);
11228                 }
11229
11230                 type_t *const new_type = duplicate_type(type);
11231                 new_type->array.size_constant     = true;
11232                 new_type->array.has_implicit_size = true;
11233                 new_type->array.size              = 1;
11234
11235                 type_t *const result = typehash_insert(new_type);
11236                 if (type != result)
11237                         free_type(type);
11238
11239                 decl->type = result;
11240         }
11241 }
11242
11243 void parse(void)
11244 {
11245         lookahead_bufpos = 0;
11246         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
11247                 next_token();
11248         }
11249         current_linkage   = c_mode & _CXX ? LINKAGE_CXX : LINKAGE_C;
11250         incomplete_arrays = NEW_ARR_F(declaration_t*, 0);
11251         parse_translation_unit();
11252         complete_incomplete_arrays();
11253         DEL_ARR_F(incomplete_arrays);
11254         incomplete_arrays = NULL;
11255 }
11256
11257 /**
11258  * Initialize the parser.
11259  */
11260 void init_parser(void)
11261 {
11262         sym_anonymous = symbol_table_insert("<anonymous>");
11263
11264         if (c_mode & _MS) {
11265                 /* add predefined symbols for extended-decl-modifier */
11266                 sym_align      = symbol_table_insert("align");
11267                 sym_allocate   = symbol_table_insert("allocate");
11268                 sym_dllimport  = symbol_table_insert("dllimport");
11269                 sym_dllexport  = symbol_table_insert("dllexport");
11270                 sym_naked      = symbol_table_insert("naked");
11271                 sym_noinline   = symbol_table_insert("noinline");
11272                 sym_noreturn   = symbol_table_insert("noreturn");
11273                 sym_nothrow    = symbol_table_insert("nothrow");
11274                 sym_novtable   = symbol_table_insert("novtable");
11275                 sym_property   = symbol_table_insert("property");
11276                 sym_get        = symbol_table_insert("get");
11277                 sym_put        = symbol_table_insert("put");
11278                 sym_selectany  = symbol_table_insert("selectany");
11279                 sym_thread     = symbol_table_insert("thread");
11280                 sym_uuid       = symbol_table_insert("uuid");
11281                 sym_deprecated = symbol_table_insert("deprecated");
11282                 sym_restrict   = symbol_table_insert("restrict");
11283                 sym_noalias    = symbol_table_insert("noalias");
11284         }
11285         memset(token_anchor_set, 0, sizeof(token_anchor_set));
11286
11287         init_expression_parsers();
11288         obstack_init(&temp_obst);
11289
11290         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
11291         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
11292 }
11293
11294 /**
11295  * Terminate the parser.
11296  */
11297 void exit_parser(void)
11298 {
11299         obstack_free(&temp_obst, NULL);
11300 }