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 "lang_features.h"
  37 #include "warning.h"
  38 #include "adt/bitfiddle.h"
  39 #include "adt/error.h"
  40 #include "adt/array.h"
  41
  42 /** if wchar_t is equal to unsigned short. */
  43 bool opt_short_wchar_t =
  44 #ifdef _WIN32
  45         true;
  46 #else
  47         false;
  48 #endif
  49
  50 //#define PRINT_TOKENS
  51 #define MAX_LOOKAHEAD 2
  52
  53 typedef struct {
  54         declaration_t *old_declaration;
  55         symbol_t      *symbol;
  56         unsigned short namespc;
  57 } stack_entry_t;
  58
  59 typedef struct argument_list_t argument_list_t;
  60 struct argument_list_t {
  61         long              argument;
  62         argument_list_t  *next;
  63 };
  64
  65 typedef struct gnu_attribute_t gnu_attribute_t;
  66 struct gnu_attribute_t {
  67         gnu_attribute_kind_t kind;           /**< The kind of the GNU attribute. */
  68         gnu_attribute_t     *next;
  69         bool                 invalid;        /**< Set if this attribute had argument errors, */
  70         bool                 have_arguments; /**< True, if this attribute has arguments. */
  71         union {
  72                 size_t              value;
  73                 string_t            string;
  74                 atomic_type_kind_t  akind;
  75                 long                argument;  /**< Single argument. */
  76                 argument_list_t    *arguments; /**< List of argument expressions. */
  77         } u;
  78 };
  79
  80 typedef struct declaration_specifiers_t  declaration_specifiers_t;
  81 struct declaration_specifiers_t {
  82         source_position_t  source_position;
  83         unsigned char      declared_storage_class;
  84         unsigned char      alignment;         /**< Alignment, 0 if not set. */
  85         unsigned int       is_inline : 1;
  86         unsigned int       deprecated : 1;
  87         decl_modifiers_t   modifiers;         /**< declaration modifiers */
  88         gnu_attribute_t   *gnu_attributes;    /**< list of GNU attributes */
  89         const char        *deprecated_string; /**< can be set if declaration was marked deprecated. */
  90         symbol_t          *get_property_sym;  /**< the name of the get property if set. */
  91         symbol_t          *put_property_sym;  /**< the name of the put property if set. */
  92         type_t            *type;
  93 };
  94
  95 /**
  96  * An environment for parsing initializers (and compound literals).
  97  */
  98 typedef struct parse_initializer_env_t {
  99         type_t        *type;        /**< the type of the initializer. In case of an
 100                                          array type with unspecified size this gets
 101                                          adjusted to the actual size. */
 102         declaration_t *declaration; /**< the declaration that is initialized if any */
 103         bool           must_be_constant;
 104 } parse_initializer_env_t;
 105
 106 typedef declaration_t* (*parsed_declaration_func) (declaration_t *declaration, bool is_definition);
 107
 108 static token_t             token;
 109 static token_t             lookahead_buffer[MAX_LOOKAHEAD];
 110 static int                 lookahead_bufpos;
 111 static stack_entry_t      *environment_stack = NULL;
 112 static stack_entry_t      *label_stack       = NULL;
 113 static stack_entry_t      *local_label_stack = NULL;
 114 static scope_t            *global_scope      = NULL;
 115 static scope_t            *scope             = NULL;
 116 static declaration_t      *last_declaration  = NULL;
 117 static declaration_t      *current_function  = NULL;
 118 static declaration_t      *current_init_decl = NULL;
 119 static switch_statement_t *current_switch    = NULL;
 120 static statement_t        *current_loop      = NULL;
 121 static statement_t        *current_parent    = NULL;
 122 static ms_try_statement_t *current_try       = NULL;
 123 static goto_statement_t   *goto_first        = NULL;
 124 static goto_statement_t   *goto_last         = NULL;
 125 static label_statement_t  *label_first       = NULL;
 126 static label_statement_t  *label_last        = NULL;
 127 static translation_unit_t *unit              = NULL;
 128 static struct obstack      temp_obst;
 129
 130 #define PUSH_PARENT(stmt)                          \
 131         statement_t *const prev_parent = current_parent; \
 132         current_parent = (stmt);
 133 #define POP_PARENT ((void)(current_parent = prev_parent))
 134
 135 static source_position_t null_position = { NULL, 0 };
 136
 137 /* symbols for Microsoft extended-decl-modifier */
 138 static const symbol_t *sym_align      = NULL;
 139 static const symbol_t *sym_allocate   = NULL;
 140 static const symbol_t *sym_dllimport  = NULL;
 141 static const symbol_t *sym_dllexport  = NULL;
 142 static const symbol_t *sym_naked      = NULL;
 143 static const symbol_t *sym_noinline   = NULL;
 144 static const symbol_t *sym_noreturn   = NULL;
 145 static const symbol_t *sym_nothrow    = NULL;
 146 static const symbol_t *sym_novtable   = NULL;
 147 static const symbol_t *sym_property   = NULL;
 148 static const symbol_t *sym_get        = NULL;
 149 static const symbol_t *sym_put        = NULL;
 150 static const symbol_t *sym_selectany  = NULL;
 151 static const symbol_t *sym_thread     = NULL;
 152 static const symbol_t *sym_uuid       = NULL;
 153 static const symbol_t *sym_deprecated = NULL;
 154 static const symbol_t *sym_restrict   = NULL;
 155 static const symbol_t *sym_noalias    = NULL;
 156
 157 /** The token anchor set */
 158 static unsigned char token_anchor_set[T_LAST_TOKEN];
 159
 160 /** The current source position. */
 161 #define HERE (&token.source_position)
 162
 163 static type_t *type_valist;
 164
 165 static statement_t *parse_compound_statement(bool inside_expression_statement);
 166 static statement_t *parse_statement(void);
 167
 168 static expression_t *parse_sub_expression(unsigned precedence);
 169 static expression_t *parse_expression(void);
 170 static type_t       *parse_typename(void);
 171
 172 static void parse_compound_type_entries(declaration_t *compound_declaration);
 173 static declaration_t *parse_declarator(
 174                 const declaration_specifiers_t *specifiers, bool may_be_abstract);
 175 static declaration_t *record_declaration(declaration_t *declaration, bool is_definition);
 176
 177 static void semantic_comparison(binary_expression_t *expression);
 178
 179 #define STORAGE_CLASSES     \
 180         case T_typedef:         \
 181         case T_extern:          \
 182         case T_static:          \
 183         case T_auto:            \
 184         case T_register:        \
 185         case T___thread:
 186
 187 #define TYPE_QUALIFIERS     \
 188         case T_const:           \
 189         case T_restrict:        \
 190         case T_volatile:        \
 191         case T_inline:          \
 192         case T__forceinline:    \
 193         case T___attribute__:
 194
 195 #ifdef PROVIDE_COMPLEX
 196 #define COMPLEX_SPECIFIERS  \
 197         case T__Complex:
 198 #define IMAGINARY_SPECIFIERS \
 199         case T__Imaginary:
 200 #else
 201 #define COMPLEX_SPECIFIERS
 202 #define IMAGINARY_SPECIFIERS
 203 #endif
 204
 205 #define TYPE_SPECIFIERS       \
 206         case T_void:              \
 207         case T_char:              \
 208         case T_short:             \
 209         case T_int:               \
 210         case T_long:              \
 211         case T_float:             \
 212         case T_double:            \
 213         case T_signed:            \
 214         case T_unsigned:          \
 215         case T__Bool:             \
 216         case T_struct:            \
 217         case T_union:             \
 218         case T_enum:              \
 219         case T___typeof__:        \
 220         case T___builtin_va_list: \
 221         case T__declspec:         \
 222         COMPLEX_SPECIFIERS        \
 223         IMAGINARY_SPECIFIERS
 224
 225 #define DECLARATION_START   \
 226         STORAGE_CLASSES         \
 227         TYPE_QUALIFIERS         \
 228         TYPE_SPECIFIERS
 229
 230 #define TYPENAME_START      \
 231         TYPE_QUALIFIERS         \
 232         TYPE_SPECIFIERS
 233
 234 /**
 235  * Allocate an AST node with given size and
 236  * initialize all fields with zero.
 237  */
 238 static void *allocate_ast_zero(size_t size)
 239 {
 240         void *res = allocate_ast(size);
 241         memset(res, 0, size);
 242         return res;
 243 }
 244
 245 static declaration_t *allocate_declaration_zero(void)
 246 {
 247         declaration_t *declaration = allocate_ast_zero(sizeof(declaration_t));
 248         declaration->type      = type_error_type;
 249         declaration->alignment = 0;
 250         return declaration;
 251 }
 252
 253 /**
 254  * Returns the size of a statement node.
 255  *
 256  * @param kind  the statement kind
 257  */
 258 static size_t get_statement_struct_size(statement_kind_t kind)
 259 {
 260         static const size_t sizes[] = {
 261                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 262                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 263                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 264                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 265                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 266                 [STATEMENT_IF]          = sizeof(if_statement_t),
 267                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 268                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 269                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 270                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 271                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 272                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 273                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 274                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 275                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 276                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 277                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 278                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 279                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 280         };
 281         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 282         assert(sizes[kind] != 0);
 283         return sizes[kind];
 284 }
 285
 286 /**
 287  * Returns the size of an expression node.
 288  *
 289  * @param kind  the expression kind
 290  */
 291 static size_t get_expression_struct_size(expression_kind_t kind)
 292 {
 293         static const size_t sizes[] = {
 294                 [EXPR_INVALID]                 = sizeof(expression_base_t),
 295                 [EXPR_REFERENCE]               = sizeof(reference_expression_t),
 296                 [EXPR_CONST]                   = sizeof(const_expression_t),
 297                 [EXPR_CHARACTER_CONSTANT]      = sizeof(const_expression_t),
 298                 [EXPR_WIDE_CHARACTER_CONSTANT] = sizeof(const_expression_t),
 299                 [EXPR_STRING_LITERAL]          = sizeof(string_literal_expression_t),
 300                 [EXPR_WIDE_STRING_LITERAL]     = sizeof(wide_string_literal_expression_t),
 301                 [EXPR_COMPOUND_LITERAL]        = sizeof(compound_literal_expression_t),
 302                 [EXPR_CALL]                    = sizeof(call_expression_t),
 303                 [EXPR_UNARY_FIRST]             = sizeof(unary_expression_t),
 304                 [EXPR_BINARY_FIRST]            = sizeof(binary_expression_t),
 305                 [EXPR_CONDITIONAL]             = sizeof(conditional_expression_t),
 306                 [EXPR_SELECT]                  = sizeof(select_expression_t),
 307                 [EXPR_ARRAY_ACCESS]            = sizeof(array_access_expression_t),
 308                 [EXPR_SIZEOF]                  = sizeof(typeprop_expression_t),
 309                 [EXPR_ALIGNOF]                 = sizeof(typeprop_expression_t),
 310                 [EXPR_CLASSIFY_TYPE]           = sizeof(classify_type_expression_t),
 311                 [EXPR_FUNCNAME]                = sizeof(funcname_expression_t),
 312                 [EXPR_BUILTIN_SYMBOL]          = sizeof(builtin_symbol_expression_t),
 313                 [EXPR_BUILTIN_CONSTANT_P]      = sizeof(builtin_constant_expression_t),
 314                 [EXPR_BUILTIN_PREFETCH]        = sizeof(builtin_prefetch_expression_t),
 315                 [EXPR_OFFSETOF]                = sizeof(offsetof_expression_t),
 316                 [EXPR_VA_START]                = sizeof(va_start_expression_t),
 317                 [EXPR_VA_ARG]                  = sizeof(va_arg_expression_t),
 318                 [EXPR_STATEMENT]               = sizeof(statement_expression_t),
 319                 [EXPR_LABEL_ADDRESS]           = sizeof(label_address_expression_t),
 320         };
 321         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 322                 return sizes[EXPR_UNARY_FIRST];
 323         }
 324         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 325                 return sizes[EXPR_BINARY_FIRST];
 326         }
 327         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 328         assert(sizes[kind] != 0);
 329         return sizes[kind];
 330 }
 331
 332 /**
 333  * Allocate a statement node of given kind and initialize all
 334  * fields with zero.
 335  */
 336 static statement_t *allocate_statement_zero(statement_kind_t kind)
 337 {
 338         size_t       size = get_statement_struct_size(kind);
 339         statement_t *res  = allocate_ast_zero(size);
 340
 341         res->base.kind   = kind;
 342         res->base.parent = current_parent;
 343         return res;
 344 }
 345
 346 /**
 347  * Allocate an expression node of given kind and initialize all
 348  * fields with zero.
 349  */
 350 static expression_t *allocate_expression_zero(expression_kind_t kind)
 351 {
 352         size_t        size = get_expression_struct_size(kind);
 353         expression_t *res  = allocate_ast_zero(size);
 354
 355         res->base.kind = kind;
 356         res->base.type = type_error_type;
 357         return res;
 358 }
 359
 360 /**
 361  * Creates a new invalid expression.
 362  */
 363 static expression_t *create_invalid_expression(void)
 364 {
 365         expression_t *expression         = allocate_expression_zero(EXPR_INVALID);
 366         expression->base.source_position = token.source_position;
 367         return expression;
 368 }
 369
 370 /**
 371  * Creates a new invalid statement.
 372  */
 373 static statement_t *create_invalid_statement(void)
 374 {
 375         statement_t *statement          = allocate_statement_zero(STATEMENT_INVALID);
 376         statement->base.source_position = token.source_position;
 377         return statement;
 378 }
 379
 380 /**
 381  * Allocate a new empty statement.
 382  */
 383 static statement_t *create_empty_statement(void)
 384 {
 385         statement_t *statement          = allocate_statement_zero(STATEMENT_EMPTY);
 386         statement->base.source_position = token.source_position;
 387         return statement;
 388 }
 389
 390 /**
 391  * Returns the size of a type node.
 392  *
 393  * @param kind  the type kind
 394  */
 395 static size_t get_type_struct_size(type_kind_t kind)
 396 {
 397         static const size_t sizes[] = {
 398                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
 399                 [TYPE_COMPLEX]         = sizeof(complex_type_t),
 400                 [TYPE_IMAGINARY]       = sizeof(imaginary_type_t),
 401                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
 402                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
 403                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
 404                 [TYPE_ENUM]            = sizeof(enum_type_t),
 405                 [TYPE_FUNCTION]        = sizeof(function_type_t),
 406                 [TYPE_POINTER]         = sizeof(pointer_type_t),
 407                 [TYPE_ARRAY]           = sizeof(array_type_t),
 408                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
 409                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
 410                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
 411         };
 412         assert(sizeof(sizes) / sizeof(sizes[0]) == (int) TYPE_TYPEOF + 1);
 413         assert(kind <= TYPE_TYPEOF);
 414         assert(sizes[kind] != 0);
 415         return sizes[kind];
 416 }
 417
 418 /**
 419  * Allocate a type node of given kind and initialize all
 420  * fields with zero.
 421  *
 422  * @param kind             type kind to allocate
 423  * @param source_position  the source position of the type definition
 424  */
 425 static type_t *allocate_type_zero(type_kind_t kind, const source_position_t *source_position)
 426 {
 427         size_t  size = get_type_struct_size(kind);
 428         type_t *res  = obstack_alloc(type_obst, size);
 429         memset(res, 0, size);
 430
 431         res->base.kind            = kind;
 432         res->base.source_position = *source_position;
 433         return res;
 434 }
 435
 436 /**
 437  * Returns the size of an initializer node.
 438  *
 439  * @param kind  the initializer kind
 440  */
 441 static size_t get_initializer_size(initializer_kind_t kind)
 442 {
 443         static const size_t sizes[] = {
 444                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 445                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 446                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 447                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 448                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 449         };
 450         assert(kind < sizeof(sizes) / sizeof(*sizes));
 451         assert(sizes[kind] != 0);
 452         return sizes[kind];
 453 }
 454
 455 /**
 456  * Allocate an initializer node of given kind and initialize all
 457  * fields with zero.
 458  */
 459 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 460 {
 461         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 462         result->kind          = kind;
 463
 464         return result;
 465 }
 466
 467 /**
 468  * Free a type from the type obstack.
 469  */
 470 static void free_type(void *type)
 471 {
 472         obstack_free(type_obst, type);
 473 }
 474
 475 /**
 476  * Returns the index of the top element of the environment stack.
 477  */
 478 static size_t environment_top(void)
 479 {
 480         return ARR_LEN(environment_stack);
 481 }
 482
 483 /**
 484  * Returns the index of the top element of the global label stack.
 485  */
 486 static size_t label_top(void)
 487 {
 488         return ARR_LEN(label_stack);
 489 }
 490
 491 /**
 492  * Returns the index of the top element of the local label stack.
 493  */
 494 static size_t local_label_top(void)
 495 {
 496         return ARR_LEN(local_label_stack);
 497 }
 498
 499 /**
 500  * Return the next token.
 501  */
 502 static inline void next_token(void)
 503 {
 504         token                              = lookahead_buffer[lookahead_bufpos];
 505         lookahead_buffer[lookahead_bufpos] = lexer_token;
 506         lexer_next_token();
 507
 508         lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
 509
 510 #ifdef PRINT_TOKENS
 511         print_token(stderr, &token);
 512         fprintf(stderr, "\n");
 513 #endif
 514 }
 515
 516 /**
 517  * Return the next token with a given lookahead.
 518  */
 519 static inline const token_t *look_ahead(int num)
 520 {
 521         assert(num > 0 && num <= MAX_LOOKAHEAD);
 522         int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
 523         return &lookahead_buffer[pos];
 524 }
 525
 526 /**
 527  * Adds a token to the token anchor set (a multi-set).
 528  */
 529 static void add_anchor_token(int token_type)
 530 {
 531         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 532         ++token_anchor_set[token_type];
 533 }
 534
 535 static int save_and_reset_anchor_state(int token_type)
 536 {
 537         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 538         int count = token_anchor_set[token_type];
 539         token_anchor_set[token_type] = 0;
 540         return count;
 541 }
 542
 543 static void restore_anchor_state(int token_type, int count)
 544 {
 545         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 546         token_anchor_set[token_type] = count;
 547 }
 548
 549 /**
 550  * Remove a token from the token anchor set (a multi-set).
 551  */
 552 static void rem_anchor_token(int token_type)
 553 {
 554         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 555         --token_anchor_set[token_type];
 556 }
 557
 558 static bool at_anchor(void)
 559 {
 560         if (token.type < 0)
 561                 return false;
 562         return token_anchor_set[token.type];
 563 }
 564
 565 /**
 566  * Eat tokens until a matching token is found.
 567  */
 568 static void eat_until_matching_token(int type)
 569 {
 570         int end_token;
 571         switch (type) {
 572                 case '(': end_token = ')';  break;
 573                 case '{': end_token = '}';  break;
 574                 case '[': end_token = ']';  break;
 575                 default:  end_token = type; break;
 576         }
 577
 578         unsigned parenthesis_count = 0;
 579         unsigned brace_count       = 0;
 580         unsigned bracket_count     = 0;
 581         while (token.type        != end_token ||
 582                parenthesis_count != 0         ||
 583                brace_count       != 0         ||
 584                bracket_count     != 0) {
 585                 switch (token.type) {
 586                 case T_EOF: return;
 587                 case '(': ++parenthesis_count; break;
 588                 case '{': ++brace_count;       break;
 589                 case '[': ++bracket_count;     break;
 590
 591                 case ')':
 592                         if (parenthesis_count > 0)
 593                                 --parenthesis_count;
 594                         goto check_stop;
 595
 596                 case '}':
 597                         if (brace_count > 0)
 598                                 --brace_count;
 599                         goto check_stop;
 600
 601                 case ']':
 602                         if (bracket_count > 0)
 603                                 --bracket_count;
 604 check_stop:
 605                         if (token.type        == end_token &&
 606                             parenthesis_count == 0         &&
 607                             brace_count       == 0         &&
 608                             bracket_count     == 0)
 609                                 return;
 610                         break;
 611
 612                 default:
 613                         break;
 614                 }
 615                 next_token();
 616         }
 617 }
 618
 619 /**
 620  * Eat input tokens until an anchor is found.
 621  */
 622 static void eat_until_anchor(void)
 623 {
 624         if (token.type == T_EOF)
 625                 return;
 626         while (token_anchor_set[token.type] == 0) {
 627                 if (token.type == '(' || token.type == '{' || token.type == '[')
 628                         eat_until_matching_token(token.type);
 629                 if (token.type == T_EOF)
 630                         break;
 631                 next_token();
 632         }
 633 }
 634
 635 static void eat_block(void)
 636 {
 637         eat_until_matching_token('{');
 638         if (token.type == '}')
 639                 next_token();
 640 }
 641
 642 /**
 643  * eat all token until a ';' is reached or a stop token is found.
 644  */
 645 static void eat_statement(void)
 646 {
 647         eat_until_matching_token(';');
 648         if (token.type == ';')
 649                 next_token();
 650 }
 651
 652 #define eat(token_type)  do { assert(token.type == token_type); next_token(); } while (0)
 653
 654 /**
 655  * Report a parse error because an expected token was not found.
 656  */
 657 static
 658 #if defined __GNUC__ && __GNUC__ >= 4
 659 __attribute__((sentinel))
 660 #endif
 661 void parse_error_expected(const char *message, ...)
 662 {
 663         if (message != NULL) {
 664                 errorf(HERE, "%s", message);
 665         }
 666         va_list ap;
 667         va_start(ap, message);
 668         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 669         va_end(ap);
 670 }
 671
 672 /**
 673  * Report a type error.
 674  */
 675 static void type_error(const char *msg, const source_position_t *source_position,
 676                        type_t *type)
 677 {
 678         errorf(source_position, "%s, but found type '%T'", msg, type);
 679 }
 680
 681 /**
 682  * Report an incompatible type.
 683  */
 684 static void type_error_incompatible(const char *msg,
 685                 const source_position_t *source_position, type_t *type1, type_t *type2)
 686 {
 687         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 688                msg, type1, type2);
 689 }
 690
 691 /**
 692  * Expect the the current token is the expected token.
 693  * If not, generate an error, eat the current statement,
 694  * and goto the end_error label.
 695  */
 696 #define expect(expected)                              \
 697         do {                                              \
 698     if (UNLIKELY(token.type != (expected))) {          \
 699         parse_error_expected(NULL, (expected), NULL); \
 700                 add_anchor_token(expected);                   \
 701         eat_until_anchor();                           \
 702         if (token.type == expected)                   \
 703                 next_token();                             \
 704                 rem_anchor_token(expected);                   \
 705         goto end_error;                               \
 706     }                                                 \
 707     next_token();                                     \
 708         } while (0)
 709
 710 static void set_scope(scope_t *new_scope)
 711 {
 712         if (scope != NULL) {
 713                 scope->last_declaration = last_declaration;
 714         }
 715         scope = new_scope;
 716
 717         last_declaration = new_scope->last_declaration;
 718 }
 719
 720 /**
 721  * Search a symbol in a given namespace and returns its declaration or
 722  * NULL if this symbol was not found.
 723  */
 724 static declaration_t *get_declaration(const symbol_t *const symbol,
 725                                       const namespace_t namespc)
 726 {
 727         declaration_t *declaration = symbol->declaration;
 728         for( ; declaration != NULL; declaration = declaration->symbol_next) {
 729                 if (declaration->namespc == namespc)
 730                         return declaration;
 731         }
 732
 733         return NULL;
 734 }
 735
 736 /**
 737  * pushs an environment_entry on the environment stack and links the
 738  * corresponding symbol to the new entry
 739  */
 740 static void stack_push(stack_entry_t **stack_ptr, declaration_t *declaration)
 741 {
 742         symbol_t    *symbol  = declaration->symbol;
 743         namespace_t  namespc = (namespace_t) declaration->namespc;
 744
 745         /* replace/add declaration into declaration list of the symbol */
 746         declaration_t *iter = symbol->declaration;
 747         if (iter == NULL) {
 748                 symbol->declaration = declaration;
 749         } else {
 750                 declaration_t *iter_last = NULL;
 751                 for( ; iter != NULL; iter_last = iter, iter = iter->symbol_next) {
 752                         /* replace an entry? */
 753                         if (iter->namespc == namespc) {
 754                                 if (iter_last == NULL) {
 755                                         symbol->declaration = declaration;
 756                                 } else {
 757                                         iter_last->symbol_next = declaration;
 758                                 }
 759                                 declaration->symbol_next = iter->symbol_next;
 760                                 break;
 761                         }
 762                 }
 763                 if (iter == NULL) {
 764                         assert(iter_last->symbol_next == NULL);
 765                         iter_last->symbol_next = declaration;
 766                 }
 767         }
 768
 769         /* remember old declaration */
 770         stack_entry_t entry;
 771         entry.symbol          = symbol;
 772         entry.old_declaration = iter;
 773         entry.namespc         = (unsigned short) namespc;
 774         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 775 }
 776
 777 /**
 778  * Push a declaration on the environment stack.
 779  *
 780  * @param declaration  the declaration
 781  */
 782 static void environment_push(declaration_t *declaration)
 783 {
 784         assert(declaration->source_position.input_name != NULL);
 785         assert(declaration->parent_scope != NULL);
 786         stack_push(&environment_stack, declaration);
 787 }
 788
 789 /**
 790  * Push a declaration on the global label stack.
 791  *
 792  * @param declaration  the declaration
 793  */
 794 static void label_push(declaration_t *declaration)
 795 {
 796         declaration->parent_scope = &current_function->scope;
 797         stack_push(&label_stack, declaration);
 798 }
 799
 800 /**
 801  * Push a declaration of the local label stack.
 802  *
 803  * @param declaration  the declaration
 804  */
 805 static void local_label_push(declaration_t *declaration)
 806 {
 807         assert(declaration->parent_scope != NULL);
 808         stack_push(&local_label_stack, declaration);
 809 }
 810
 811 /**
 812  * pops symbols from the environment stack until @p new_top is the top element
 813  */
 814 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 815 {
 816         stack_entry_t *stack = *stack_ptr;
 817         size_t         top   = ARR_LEN(stack);
 818         size_t         i;
 819
 820         assert(new_top <= top);
 821         if (new_top == top)
 822                 return;
 823
 824         for(i = top; i > new_top; --i) {
 825                 stack_entry_t *entry = &stack[i - 1];
 826
 827                 declaration_t *old_declaration = entry->old_declaration;
 828                 symbol_t      *symbol          = entry->symbol;
 829                 namespace_t    namespc         = (namespace_t)entry->namespc;
 830
 831                 /* replace/remove declaration */
 832                 declaration_t *declaration = symbol->declaration;
 833                 assert(declaration != NULL);
 834                 if (declaration->namespc == namespc) {
 835                         if (old_declaration == NULL) {
 836                                 symbol->declaration = declaration->symbol_next;
 837                         } else {
 838                                 symbol->declaration = old_declaration;
 839                         }
 840                 } else {
 841                         declaration_t *iter_last = declaration;
 842                         declaration_t *iter      = declaration->symbol_next;
 843                         for( ; iter != NULL; iter_last = iter, iter = iter->symbol_next) {
 844                                 /* replace an entry? */
 845                                 if (iter->namespc == namespc) {
 846                                         assert(iter_last != NULL);
 847                                         iter_last->symbol_next = old_declaration;
 848                                         if (old_declaration != NULL) {
 849                                                 old_declaration->symbol_next = iter->symbol_next;
 850                                         }
 851                                         break;
 852                                 }
 853                         }
 854                         assert(iter != NULL);
 855                 }
 856         }
 857
 858         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
 859 }
 860
 861 /**
 862  * Pop all entries from the environment stack until the new_top
 863  * is reached.
 864  *
 865  * @param new_top  the new stack top
 866  */
 867 static void environment_pop_to(size_t new_top)
 868 {
 869         stack_pop_to(&environment_stack, new_top);
 870 }
 871
 872 /**
 873  * Pop all entries from the global label stack until the new_top
 874  * is reached.
 875  *
 876  * @param new_top  the new stack top
 877  */
 878 static void label_pop_to(size_t new_top)
 879 {
 880         stack_pop_to(&label_stack, new_top);
 881 }
 882
 883 /**
 884  * Pop all entries from the local label stack until the new_top
 885  * is reached.
 886  *
 887  * @param new_top  the new stack top
 888  */
 889 static void local_label_pop_to(size_t new_top)
 890 {
 891         stack_pop_to(&local_label_stack, new_top);
 892 }
 893
 894
 895 static int get_akind_rank(atomic_type_kind_t akind)
 896 {
 897         return (int) akind;
 898 }
 899
 900 static int get_rank(const type_t *type)
 901 {
 902         assert(!is_typeref(type));
 903         /* The C-standard allows promoting enums to int or unsigned int (see § 7.2.2
 904          * and esp. footnote 108). However we can't fold constants (yet), so we
 905          * can't decide whether unsigned int is possible, while int always works.
 906          * (unsigned int would be preferable when possible... for stuff like
 907          *  struct { enum { ... } bla : 4; } ) */
 908         if (type->kind == TYPE_ENUM)
 909                 return get_akind_rank(ATOMIC_TYPE_INT);
 910
 911         assert(type->kind == TYPE_ATOMIC);
 912         return get_akind_rank(type->atomic.akind);
 913 }
 914
 915 static type_t *promote_integer(type_t *type)
 916 {
 917         if (type->kind == TYPE_BITFIELD)
 918                 type = type->bitfield.base_type;
 919
 920         if (get_rank(type) < get_akind_rank(ATOMIC_TYPE_INT))
 921                 type = type_int;
 922
 923         return type;
 924 }
 925
 926 /**
 927  * Create a cast expression.
 928  *
 929  * @param expression  the expression to cast
 930  * @param dest_type   the destination type
 931  */
 932 static expression_t *create_cast_expression(expression_t *expression,
 933                                             type_t *dest_type)
 934 {
 935         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
 936
 937         cast->unary.value = expression;
 938         cast->base.type   = dest_type;
 939
 940         return cast;
 941 }
 942
 943 /**
 944  * Check if a given expression represents the 0 pointer constant.
 945  */
 946 static bool is_null_pointer_constant(const expression_t *expression)
 947 {
 948         /* skip void* cast */
 949         if (expression->kind == EXPR_UNARY_CAST
 950                         || expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
 951                 expression = expression->unary.value;
 952         }
 953
 954         /* TODO: not correct yet, should be any constant integer expression
 955          * which evaluates to 0 */
 956         if (expression->kind != EXPR_CONST)
 957                 return false;
 958
 959         type_t *const type = skip_typeref(expression->base.type);
 960         if (!is_type_integer(type))
 961                 return false;
 962
 963         return expression->conste.v.int_value == 0;
 964 }
 965
 966 /**
 967  * Create an implicit cast expression.
 968  *
 969  * @param expression  the expression to cast
 970  * @param dest_type   the destination type
 971  */
 972 static expression_t *create_implicit_cast(expression_t *expression,
 973                                           type_t *dest_type)
 974 {
 975         type_t *const source_type = expression->base.type;
 976
 977         if (source_type == dest_type)
 978                 return expression;
 979
 980         return create_cast_expression(expression, dest_type);
 981 }
 982
 983 typedef enum assign_error_t {
 984         ASSIGN_SUCCESS,
 985         ASSIGN_ERROR_INCOMPATIBLE,
 986         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
 987         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
 988         ASSIGN_WARNING_POINTER_FROM_INT,
 989         ASSIGN_WARNING_INT_FROM_POINTER
 990 } assign_error_t;
 991
 992 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
 993                                 const expression_t *const right,
 994                                 const char *context,
 995                                 const source_position_t *source_position)
 996 {
 997         type_t *const orig_type_right = right->base.type;
 998         type_t *const type_left       = skip_typeref(orig_type_left);
 999         type_t *const type_right      = skip_typeref(orig_type_right);
1000
1001         switch (error) {
1002         case ASSIGN_SUCCESS:
1003                 return;
1004         case ASSIGN_ERROR_INCOMPATIBLE:
1005                 errorf(source_position,
1006                        "destination type '%T' in %s is incompatible with type '%T'",
1007                        orig_type_left, context, orig_type_right);
1008                 return;
1009
1010         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
1011                 type_t *points_to_left
1012                         = skip_typeref(type_left->pointer.points_to);
1013                 type_t *points_to_right
1014                         = skip_typeref(type_right->pointer.points_to);
1015
1016                 /* the left type has all qualifiers from the right type */
1017                 unsigned missing_qualifiers
1018                         = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1019                 warningf(source_position,
1020                          "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
1021                          orig_type_left, context, orig_type_right, missing_qualifiers);
1022                 return;
1023         }
1024
1025         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
1026                 warningf(source_position,
1027                          "destination type '%T' in %s is incompatible with '%E' of type '%T'",
1028                                  orig_type_left, context, right, orig_type_right);
1029                 return;
1030
1031         case ASSIGN_WARNING_POINTER_FROM_INT:
1032                 warningf(source_position,
1033                          "%s makes integer '%T' from pointer '%T' without a cast",
1034                                  context, orig_type_left, orig_type_right);
1035                 return;
1036
1037         case ASSIGN_WARNING_INT_FROM_POINTER:
1038                 warningf(source_position,
1039                                 "%s makes integer '%T' from pointer '%T' without a cast",
1040                                 context, orig_type_left, orig_type_right);
1041                 return;
1042
1043         default:
1044                 panic("invalid error value");
1045         }
1046 }
1047
1048 /** Implements the rules from § 6.5.16.1 */
1049 static assign_error_t semantic_assign(type_t *orig_type_left,
1050                                       const expression_t *const right)
1051 {
1052         type_t *const orig_type_right = right->base.type;
1053         type_t *const type_left       = skip_typeref(orig_type_left);
1054         type_t *const type_right      = skip_typeref(orig_type_right);
1055
1056         if (is_type_pointer(type_left)) {
1057                 if (is_null_pointer_constant(right)) {
1058                         return ASSIGN_SUCCESS;
1059                 } else if (is_type_pointer(type_right)) {
1060                         type_t *points_to_left
1061                                 = skip_typeref(type_left->pointer.points_to);
1062                         type_t *points_to_right
1063                                 = skip_typeref(type_right->pointer.points_to);
1064                         assign_error_t res = ASSIGN_SUCCESS;
1065
1066                         /* the left type has all qualifiers from the right type */
1067                         unsigned missing_qualifiers
1068                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1069                         if (missing_qualifiers != 0) {
1070                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1071                         }
1072
1073                         points_to_left  = get_unqualified_type(points_to_left);
1074                         points_to_right = get_unqualified_type(points_to_right);
1075
1076                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID) ||
1077                                         is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1078                                 return res;
1079                         }
1080
1081                         if (!types_compatible(points_to_left, points_to_right)) {
1082                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1083                         }
1084
1085                         return res;
1086                 } else if (is_type_integer(type_right)) {
1087                         return ASSIGN_WARNING_POINTER_FROM_INT;
1088                 }
1089         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1090             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1091                 && is_type_pointer(type_right))) {
1092                 return ASSIGN_SUCCESS;
1093         } else if ((is_type_compound(type_left)  && is_type_compound(type_right))
1094                         || (is_type_builtin(type_left) && is_type_builtin(type_right))) {
1095                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1096                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1097                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1098                         return ASSIGN_SUCCESS;
1099                 }
1100         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1101                 return ASSIGN_WARNING_INT_FROM_POINTER;
1102         }
1103
1104         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1105                 return ASSIGN_SUCCESS;
1106
1107         return ASSIGN_ERROR_INCOMPATIBLE;
1108 }
1109
1110 static expression_t *parse_constant_expression(void)
1111 {
1112         /* start parsing at precedence 7 (conditional expression) */
1113         expression_t *result = parse_sub_expression(7);
1114
1115         if (!is_constant_expression(result)) {
1116                 errorf(&result->base.source_position,
1117                        "expression '%E' is not constant\n", result);
1118         }
1119
1120         return result;
1121 }
1122
1123 static expression_t *parse_assignment_expression(void)
1124 {
1125         /* start parsing at precedence 2 (assignment expression) */
1126         return parse_sub_expression(2);
1127 }
1128
1129 static type_t *make_global_typedef(const char *name, type_t *type)
1130 {
1131         symbol_t *const symbol       = symbol_table_insert(name);
1132
1133         declaration_t *const declaration = allocate_declaration_zero();
1134         declaration->namespc                = NAMESPACE_NORMAL;
1135         declaration->storage_class          = STORAGE_CLASS_TYPEDEF;
1136         declaration->declared_storage_class = STORAGE_CLASS_TYPEDEF;
1137         declaration->type                   = type;
1138         declaration->symbol                 = symbol;
1139         declaration->source_position        = builtin_source_position;
1140         declaration->implicit               = true;
1141
1142         record_declaration(declaration, false);
1143
1144         type_t *typedef_type               = allocate_type_zero(TYPE_TYPEDEF, &builtin_source_position);
1145         typedef_type->typedeft.declaration = declaration;
1146
1147         return typedef_type;
1148 }
1149
1150 static string_t parse_string_literals(void)
1151 {
1152         assert(token.type == T_STRING_LITERAL);
1153         string_t result = token.v.string;
1154
1155         next_token();
1156
1157         while (token.type == T_STRING_LITERAL) {
1158                 result = concat_strings(&result, &token.v.string);
1159                 next_token();
1160         }
1161
1162         return result;
1163 }
1164
1165 static const char *const gnu_attribute_names[GNU_AK_LAST] = {
1166         [GNU_AK_CONST]                  = "const",
1167         [GNU_AK_VOLATILE]               = "volatile",
1168         [GNU_AK_CDECL]                  = "cdecl",
1169         [GNU_AK_STDCALL]                = "stdcall",
1170         [GNU_AK_FASTCALL]               = "fastcall",
1171         [GNU_AK_DEPRECATED]             = "deprecated",
1172         [GNU_AK_NOINLINE]               = "noinline",
1173         [GNU_AK_NORETURN]               = "noreturn",
1174         [GNU_AK_NAKED]                  = "naked",
1175         [GNU_AK_PURE]                   = "pure",
1176         [GNU_AK_ALWAYS_INLINE]          = "always_inline",
1177         [GNU_AK_MALLOC]                 = "malloc",
1178         [GNU_AK_WEAK]                   = "weak",
1179         [GNU_AK_CONSTRUCTOR]            = "constructor",
1180         [GNU_AK_DESTRUCTOR]             = "destructor",
1181         [GNU_AK_NOTHROW]                = "nothrow",
1182         [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
1183         [GNU_AK_COMMON]                 = "common",
1184         [GNU_AK_NOCOMMON]               = "nocommon",
1185         [GNU_AK_PACKED]                 = "packed",
1186         [GNU_AK_SHARED]                 = "shared",
1187         [GNU_AK_NOTSHARED]              = "notshared",
1188         [GNU_AK_USED]                   = "used",
1189         [GNU_AK_UNUSED]                 = "unused",
1190         [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
1191         [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
1192         [GNU_AK_LONGCALL]               = "longcall",
1193         [GNU_AK_SHORTCALL]              = "shortcall",
1194         [GNU_AK_LONG_CALL]              = "long_call",
1195         [GNU_AK_SHORT_CALL]             = "short_call",
1196         [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
1197         [GNU_AK_INTERRUPT]              = "interrupt",
1198         [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
1199         [GNU_AK_NMI_HANDLER]            = "nmi_handler",
1200         [GNU_AK_NESTING]                = "nesting",
1201         [GNU_AK_NEAR]                   = "near",
1202         [GNU_AK_FAR]                    = "far",
1203         [GNU_AK_SIGNAL]                 = "signal",
1204         [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
1205         [GNU_AK_TINY_DATA]              = "tiny_data",
1206         [GNU_AK_SAVEALL]                = "saveall",
1207         [GNU_AK_FLATTEN]                = "flatten",
1208         [GNU_AK_SSEREGPARM]             = "sseregparm",
1209         [GNU_AK_EXTERNALLY_VISIBLE]     = "externally_visible",
1210         [GNU_AK_RETURN_TWICE]           = "return_twice",
1211         [GNU_AK_MAY_ALIAS]              = "may_alias",
1212         [GNU_AK_MS_STRUCT]              = "ms_struct",
1213         [GNU_AK_GCC_STRUCT]             = "gcc_struct",
1214         [GNU_AK_DLLIMPORT]              = "dllimport",
1215         [GNU_AK_DLLEXPORT]              = "dllexport",
1216         [GNU_AK_ALIGNED]                = "aligned",
1217         [GNU_AK_ALIAS]                  = "alias",
1218         [GNU_AK_SECTION]                = "section",
1219         [GNU_AK_FORMAT]                 = "format",
1220         [GNU_AK_FORMAT_ARG]             = "format_arg",
1221         [GNU_AK_WEAKREF]                = "weakref",
1222         [GNU_AK_NONNULL]                = "nonnull",
1223         [GNU_AK_TLS_MODEL]              = "tls_model",
1224         [GNU_AK_VISIBILITY]             = "visibility",
1225         [GNU_AK_REGPARM]                = "regparm",
1226         [GNU_AK_MODE]                   = "mode",
1227         [GNU_AK_MODEL]                  = "model",
1228         [GNU_AK_TRAP_EXIT]              = "trap_exit",
1229         [GNU_AK_SP_SWITCH]              = "sp_switch",
1230         [GNU_AK_SENTINEL]               = "sentinel"
1231 };
1232
1233 /**
1234  * compare two string, ignoring double underscores on the second.
1235  */
1236 static int strcmp_underscore(const char *s1, const char *s2)
1237 {
1238         if (s2[0] == '_' && s2[1] == '_') {
1239                 size_t len2 = strlen(s2);
1240                 size_t len1 = strlen(s1);
1241                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1242                         return strncmp(s1, s2+2, len2-4);
1243                 }
1244         }
1245
1246         return strcmp(s1, s2);
1247 }
1248
1249 /**
1250  * Allocate a new gnu temporal attribute.
1251  */
1252 static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
1253 {
1254         gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
1255         attribute->kind            = kind;
1256         attribute->next            = NULL;
1257         attribute->invalid         = false;
1258         attribute->have_arguments  = false;
1259
1260         return attribute;
1261 }
1262
1263 /**
1264  * parse one constant expression argument.
1265  */
1266 static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
1267 {
1268         expression_t *expression;
1269         add_anchor_token(')');
1270         expression = parse_constant_expression();
1271         rem_anchor_token(')');
1272         expect(')');
1273         attribute->u.argument = fold_constant(expression);
1274         return;
1275 end_error:
1276         attribute->invalid = true;
1277 }
1278
1279 /**
1280  * parse a list of constant expressions arguments.
1281  */
1282 static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
1283 {
1284         argument_list_t **list = &attribute->u.arguments;
1285         argument_list_t  *entry;
1286         expression_t     *expression;
1287         add_anchor_token(')');
1288         add_anchor_token(',');
1289         while (true) {
1290                 expression = parse_constant_expression();
1291                 entry = obstack_alloc(&temp_obst, sizeof(entry));
1292                 entry->argument = fold_constant(expression);
1293                 entry->next     = NULL;
1294                 *list = entry;
1295                 list = &entry->next;
1296                 if (token.type != ',')
1297                         break;
1298                 next_token();
1299         }
1300         rem_anchor_token(',');
1301         rem_anchor_token(')');
1302         expect(')');
1303         return;
1304 end_error:
1305         attribute->invalid = true;
1306 }
1307
1308 /**
1309  * parse one string literal argument.
1310  */
1311 static void parse_gnu_attribute_string_arg(gnu_attribute_t *attribute,
1312                                            string_t *string)
1313 {
1314         add_anchor_token('(');
1315         if (token.type != T_STRING_LITERAL) {
1316                 parse_error_expected("while parsing attribute directive",
1317                                      T_STRING_LITERAL, NULL);
1318                 goto end_error;
1319         }
1320         *string = parse_string_literals();
1321         rem_anchor_token('(');
1322         expect(')');
1323         return;
1324 end_error:
1325         attribute->invalid = true;
1326 }
1327
1328 /**
1329  * parse one tls model.
1330  */
1331 static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
1332 {
1333         static const char *const tls_models[] = {
1334                 "global-dynamic",
1335                 "local-dynamic",
1336                 "initial-exec",
1337                 "local-exec"
1338         };
1339         string_t string = { NULL, 0 };
1340         parse_gnu_attribute_string_arg(attribute, &string);
1341         if (string.begin != NULL) {
1342                 for(size_t i = 0; i < 4; ++i) {
1343                         if (strcmp(tls_models[i], string.begin) == 0) {
1344                                 attribute->u.value = i;
1345                                 return;
1346                         }
1347                 }
1348                 errorf(HERE, "'%s' is an unrecognized tls model", string.begin);
1349         }
1350         attribute->invalid = true;
1351 }
1352
1353 /**
1354  * parse one tls model.
1355  */
1356 static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
1357 {
1358         static const char *const visibilities[] = {
1359                 "default",
1360                 "protected",
1361                 "hidden",
1362                 "internal"
1363         };
1364         string_t string = { NULL, 0 };
1365         parse_gnu_attribute_string_arg(attribute, &string);
1366         if (string.begin != NULL) {
1367                 for(size_t i = 0; i < 4; ++i) {
1368                         if (strcmp(visibilities[i], string.begin) == 0) {
1369                                 attribute->u.value = i;
1370                                 return;
1371                         }
1372                 }
1373                 errorf(HERE, "'%s' is an unrecognized visibility", string.begin);
1374         }
1375         attribute->invalid = true;
1376 }
1377
1378 /**
1379  * parse one (code) model.
1380  */
1381 static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
1382 {
1383         static const char *const visibilities[] = {
1384                 "small",
1385                 "medium",
1386                 "large"
1387         };
1388         string_t string = { NULL, 0 };
1389         parse_gnu_attribute_string_arg(attribute, &string);
1390         if (string.begin != NULL) {
1391                 for(int i = 0; i < 3; ++i) {
1392                         if (strcmp(visibilities[i], string.begin) == 0) {
1393                                 attribute->u.value = i;
1394                                 return;
1395                         }
1396                 }
1397                 errorf(HERE, "'%s' is an unrecognized model", string.begin);
1398         }
1399         attribute->invalid = true;
1400 }
1401
1402 static void parse_gnu_attribute_mode_arg(gnu_attribute_t *attribute)
1403 {
1404         /* TODO: find out what is allowed here... */
1405
1406         /* at least: byte, word, pointer, list of machine modes
1407          * __XXX___ is interpreted as XXX */
1408         add_anchor_token(')');
1409
1410         if (token.type != T_IDENTIFIER) {
1411                 expect(T_IDENTIFIER);
1412         }
1413
1414         /* This isn't really correct, the backend should provide a list of machine
1415          * specific modes (according to gcc philosophy that is...) */
1416         const char *symbol_str = token.v.symbol->string;
1417         if (strcmp_underscore("QI",   symbol_str) == 0 ||
1418             strcmp_underscore("byte", symbol_str) == 0) {
1419                 attribute->u.akind = ATOMIC_TYPE_CHAR;
1420         } else if (strcmp_underscore("HI", symbol_str) == 0) {
1421                 attribute->u.akind = ATOMIC_TYPE_SHORT;
1422         } else if (strcmp_underscore("SI",      symbol_str) == 0
1423                 || strcmp_underscore("word",    symbol_str) == 0
1424                 || strcmp_underscore("pointer", symbol_str) == 0) {
1425                 attribute->u.akind = ATOMIC_TYPE_INT;
1426         } else if (strcmp_underscore("DI", symbol_str) == 0) {
1427                 attribute->u.akind = ATOMIC_TYPE_LONGLONG;
1428         } else {
1429                 warningf(HERE, "ignoring unknown mode '%s'", symbol_str);
1430                 attribute->invalid = true;
1431         }
1432         next_token();
1433
1434         rem_anchor_token(')');
1435         expect(')');
1436         return;
1437 end_error:
1438         attribute->invalid = true;
1439 }
1440
1441 /**
1442  * parse one interrupt argument.
1443  */
1444 static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
1445 {
1446         static const char *const interrupts[] = {
1447                 "IRQ",
1448                 "FIQ",
1449                 "SWI",
1450                 "ABORT",
1451                 "UNDEF"
1452         };
1453         string_t string = { NULL, 0 };
1454         parse_gnu_attribute_string_arg(attribute, &string);
1455         if (string.begin != NULL) {
1456                 for(size_t i = 0; i < 5; ++i) {
1457                         if (strcmp(interrupts[i], string.begin) == 0) {
1458                                 attribute->u.value = i;
1459                                 return;
1460                         }
1461                 }
1462                 errorf(HERE, "'%s' is not an interrupt", string.begin);
1463         }
1464         attribute->invalid = true;
1465 }
1466
1467 /**
1468  * parse ( identifier, const expression, const expression )
1469  */
1470 static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
1471 {
1472         static const char *const format_names[] = {
1473                 "printf",
1474                 "scanf",
1475                 "strftime",
1476                 "strfmon"
1477         };
1478         int i;
1479
1480         if (token.type != T_IDENTIFIER) {
1481                 parse_error_expected("while parsing format attribute directive", T_IDENTIFIER, NULL);
1482                 goto end_error;
1483         }
1484         const char *name = token.v.symbol->string;
1485         for(i = 0; i < 4; ++i) {
1486                 if (strcmp_underscore(format_names[i], name) == 0)
1487                         break;
1488         }
1489         if (i >= 4) {
1490                 if (warning.attribute)
1491                         warningf(HERE, "'%s' is an unrecognized format function type", name);
1492         }
1493         next_token();
1494
1495         expect(',');
1496         add_anchor_token(')');
1497         add_anchor_token(',');
1498         parse_constant_expression();
1499         rem_anchor_token(',');
1500         rem_anchor_token('(');
1501
1502         expect(',');
1503         add_anchor_token(')');
1504         parse_constant_expression();
1505         rem_anchor_token('(');
1506         expect(')');
1507         return;
1508 end_error:
1509         attribute->u.value = true;
1510 }
1511
1512 static void check_no_argument(gnu_attribute_t *attribute, const char *name)
1513 {
1514         if (!attribute->have_arguments)
1515                 return;
1516
1517         /* should have no arguments */
1518         errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1519         eat_until_matching_token('(');
1520         /* we have already consumed '(', so we stop before ')', eat it */
1521         eat(')');
1522         attribute->invalid = true;
1523 }
1524
1525 /**
1526  * Parse one GNU attribute.
1527  *
1528  * Note that attribute names can be specified WITH or WITHOUT
1529  * double underscores, ie const or __const__.
1530  *
1531  * The following attributes are parsed without arguments
1532  *  const
1533  *  volatile
1534  *  cdecl
1535  *  stdcall
1536  *  fastcall
1537  *  deprecated
1538  *  noinline
1539  *  noreturn
1540  *  naked
1541  *  pure
1542  *  always_inline
1543  *  malloc
1544  *  weak
1545  *  constructor
1546  *  destructor
1547  *  nothrow
1548  *  transparent_union
1549  *  common
1550  *  nocommon
1551  *  packed
1552  *  shared
1553  *  notshared
1554  *  used
1555  *  unused
1556  *  no_instrument_function
1557  *  warn_unused_result
1558  *  longcall
1559  *  shortcall
1560  *  long_call
1561  *  short_call
1562  *  function_vector
1563  *  interrupt_handler
1564  *  nmi_handler
1565  *  nesting
1566  *  near
1567  *  far
1568  *  signal
1569  *  eightbit_data
1570  *  tiny_data
1571  *  saveall
1572  *  flatten
1573  *  sseregparm
1574  *  externally_visible
1575  *  return_twice
1576  *  may_alias
1577  *  ms_struct
1578  *  gcc_struct
1579  *  dllimport
1580  *  dllexport
1581  *
1582  * The following attributes are parsed with arguments
1583  *  aligned( const expression )
1584  *  alias( string literal )
1585  *  section( string literal )
1586  *  format( identifier, const expression, const expression )
1587  *  format_arg( const expression )
1588  *  tls_model( string literal )
1589  *  visibility( string literal )
1590  *  regparm( const expression )
1591  *  model( string leteral )
1592  *  trap_exit( const expression )
1593  *  sp_switch( string literal )
1594  *
1595  * The following attributes might have arguments
1596  *  weak_ref( string literal )
1597  *  non_null( const expression // ',' )
1598  *  interrupt( string literal )
1599  *  sentinel( constant expression )
1600  */
1601 static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
1602 {
1603         gnu_attribute_t *head      = *attributes;
1604         gnu_attribute_t *last      = *attributes;
1605         decl_modifiers_t modifiers = 0;
1606         gnu_attribute_t *attribute;
1607
1608         eat(T___attribute__);
1609         expect('(');
1610         expect('(');
1611
1612         if (token.type != ')') {
1613                 /* find the end of the list */
1614                 if (last != NULL) {
1615                         while (last->next != NULL)
1616                                 last = last->next;
1617                 }
1618
1619                 /* non-empty attribute list */
1620                 while (true) {
1621                         const char *name;
1622                         if (token.type == T_const) {
1623                                 name = "const";
1624                         } else if (token.type == T_volatile) {
1625                                 name = "volatile";
1626                         } else if (token.type == T_cdecl) {
1627                                 /* __attribute__((cdecl)), WITH ms mode */
1628                                 name = "cdecl";
1629                         } else if (token.type == T_IDENTIFIER) {
1630                                 const symbol_t *sym = token.v.symbol;
1631                                 name = sym->string;
1632                         } else {
1633                                 parse_error_expected("while parsing GNU attribute", T_IDENTIFIER, NULL);
1634                                 break;
1635                         }
1636
1637                         next_token();
1638
1639                         int i;
1640                         for(i = 0; i < GNU_AK_LAST; ++i) {
1641                                 if (strcmp_underscore(gnu_attribute_names[i], name) == 0)
1642                                         break;
1643                         }
1644                         gnu_attribute_kind_t kind = (gnu_attribute_kind_t)i;
1645
1646                         attribute = NULL;
1647                         if (kind == GNU_AK_LAST) {
1648                                 if (warning.attribute)
1649                                         warningf(HERE, "'%s' attribute directive ignored", name);
1650
1651                                 /* skip possible arguments */
1652                                 if (token.type == '(') {
1653                                         eat_until_matching_token(')');
1654                                 }
1655                         } else {
1656                                 /* check for arguments */
1657                                 attribute = allocate_gnu_attribute(kind);
1658                                 if (token.type == '(') {
1659                                         next_token();
1660                                         if (token.type == ')') {
1661                                                 /* empty args are allowed */
1662                                                 next_token();
1663                                         } else
1664                                                 attribute->have_arguments = true;
1665                                 }
1666
1667                                 switch(kind) {
1668                                 case GNU_AK_CONST:
1669                                 case GNU_AK_VOLATILE:
1670                                 case GNU_AK_NAKED:
1671                                 case GNU_AK_MALLOC:
1672                                 case GNU_AK_WEAK:
1673                                 case GNU_AK_COMMON:
1674                                 case GNU_AK_NOCOMMON:
1675                                 case GNU_AK_SHARED:
1676                                 case GNU_AK_NOTSHARED:
1677                                 case GNU_AK_NO_INSTRUMENT_FUNCTION:
1678                                 case GNU_AK_WARN_UNUSED_RESULT:
1679                                 case GNU_AK_LONGCALL:
1680                                 case GNU_AK_SHORTCALL:
1681                                 case GNU_AK_LONG_CALL:
1682                                 case GNU_AK_SHORT_CALL:
1683                                 case GNU_AK_FUNCTION_VECTOR:
1684                                 case GNU_AK_INTERRUPT_HANDLER:
1685                                 case GNU_AK_NMI_HANDLER:
1686                                 case GNU_AK_NESTING:
1687                                 case GNU_AK_NEAR:
1688                                 case GNU_AK_FAR:
1689                                 case GNU_AK_SIGNAL:
1690                                 case GNU_AK_EIGTHBIT_DATA:
1691                                 case GNU_AK_TINY_DATA:
1692                                 case GNU_AK_SAVEALL:
1693                                 case GNU_AK_FLATTEN:
1694                                 case GNU_AK_SSEREGPARM:
1695                                 case GNU_AK_EXTERNALLY_VISIBLE:
1696                                 case GNU_AK_RETURN_TWICE:
1697                                 case GNU_AK_MAY_ALIAS:
1698                                 case GNU_AK_MS_STRUCT:
1699                                 case GNU_AK_GCC_STRUCT:
1700                                         goto no_arg;
1701
1702                                 case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
1703                                 case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
1704                                 case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
1705                                 case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
1706                                 case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
1707                                 case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
1708                                 case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
1709                                 case GNU_AK_DLLIMPORT:         modifiers |= DM_DLLIMPORT;         goto no_arg;
1710                                 case GNU_AK_DLLEXPORT:         modifiers |= DM_DLLEXPORT;         goto no_arg;
1711                                 case GNU_AK_PACKED:            modifiers |= DM_PACKED;            goto no_arg;
1712                                 case GNU_AK_NOINLINE:          modifiers |= DM_NOINLINE;          goto no_arg;
1713                                 case GNU_AK_NORETURN:          modifiers |= DM_NORETURN;          goto no_arg;
1714                                 case GNU_AK_NOTHROW:           modifiers |= DM_NOTHROW;           goto no_arg;
1715                                 case GNU_AK_TRANSPARENT_UNION: modifiers |= DM_TRANSPARENT_UNION; goto no_arg;
1716                                 case GNU_AK_CONSTRUCTOR:       modifiers |= DM_CONSTRUCTOR;       goto no_arg;
1717                                 case GNU_AK_DESTRUCTOR:        modifiers |= DM_DESTRUCTOR;        goto no_arg;
1718                                 case GNU_AK_DEPRECATED:        modifiers |= DM_DEPRECATED;        goto no_arg;
1719
1720                                 case GNU_AK_ALIGNED:
1721                                         /* __align__ may be used without an argument */
1722                                         if (attribute->have_arguments) {
1723                                                 parse_gnu_attribute_const_arg(attribute);
1724                                         }
1725                                         break;
1726
1727                                 case GNU_AK_FORMAT_ARG:
1728                                 case GNU_AK_REGPARM:
1729                                 case GNU_AK_TRAP_EXIT:
1730                                         if (!attribute->have_arguments) {
1731                                                 /* should have arguments */
1732                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1733                                                 attribute->invalid = true;
1734                                         } else
1735                                                 parse_gnu_attribute_const_arg(attribute);
1736                                         break;
1737                                 case GNU_AK_ALIAS:
1738                                 case GNU_AK_SECTION:
1739                                 case GNU_AK_SP_SWITCH:
1740                                         if (!attribute->have_arguments) {
1741                                                 /* should have arguments */
1742                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1743                                                 attribute->invalid = true;
1744                                         } else
1745                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1746                                         break;
1747                                 case GNU_AK_FORMAT:
1748                                         if (!attribute->have_arguments) {
1749                                                 /* should have arguments */
1750                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1751                                                 attribute->invalid = true;
1752                                         } else
1753                                                 parse_gnu_attribute_format_args(attribute);
1754                                         break;
1755                                 case GNU_AK_WEAKREF:
1756                                         /* may have one string argument */
1757                                         if (attribute->have_arguments)
1758                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1759                                         break;
1760                                 case GNU_AK_NONNULL:
1761                                         if (attribute->have_arguments)
1762                                                 parse_gnu_attribute_const_arg_list(attribute);
1763                                         break;
1764                                 case GNU_AK_TLS_MODEL:
1765                                         if (!attribute->have_arguments) {
1766                                                 /* should have arguments */
1767                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1768                                         } else
1769                                                 parse_gnu_attribute_tls_model_arg(attribute);
1770                                         break;
1771                                 case GNU_AK_VISIBILITY:
1772                                         if (!attribute->have_arguments) {
1773                                                 /* should have arguments */
1774                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1775                                         } else
1776                                                 parse_gnu_attribute_visibility_arg(attribute);
1777                                         break;
1778                                 case GNU_AK_MODEL:
1779                                         if (!attribute->have_arguments) {
1780                                                 /* should have arguments */
1781                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1782                                         } else {
1783                                                 parse_gnu_attribute_model_arg(attribute);
1784                                         }
1785                                         break;
1786                                 case GNU_AK_MODE:
1787                                         if (!attribute->have_arguments) {
1788                                                 /* should have arguments */
1789                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1790                                         } else {
1791                                                 parse_gnu_attribute_mode_arg(attribute);
1792                                         }
1793                                         break;
1794                                 case GNU_AK_INTERRUPT:
1795                                         /* may have one string argument */
1796                                         if (attribute->have_arguments)
1797                                                 parse_gnu_attribute_interrupt_arg(attribute);
1798                                         break;
1799                                 case GNU_AK_SENTINEL:
1800                                         /* may have one string argument */
1801                                         if (attribute->have_arguments)
1802                                                 parse_gnu_attribute_const_arg(attribute);
1803                                         break;
1804                                 case GNU_AK_LAST:
1805                                         /* already handled */
1806                                         break;
1807
1808 no_arg:
1809                                         check_no_argument(attribute, name);
1810                                 }
1811                         }
1812                         if (attribute != NULL) {
1813                                 if (last != NULL) {
1814                                         last->next = attribute;
1815                                         last       = attribute;
1816                                 } else {
1817                                         head = last = attribute;
1818                                 }
1819                         }
1820
1821                         if (token.type != ',')
1822                                 break;
1823                         next_token();
1824                 }
1825         }
1826         expect(')');
1827         expect(')');
1828 end_error:
1829         *attributes = head;
1830
1831         return modifiers;
1832 }
1833
1834 /**
1835  * Parse GNU attributes.
1836  */
1837 static decl_modifiers_t parse_attributes(gnu_attribute_t **attributes)
1838 {
1839         decl_modifiers_t modifiers = 0;
1840
1841         while (true) {
1842                 switch(token.type) {
1843                 case T___attribute__:
1844                         modifiers |= parse_gnu_attribute(attributes);
1845                         continue;
1846
1847                 case T_asm:
1848                         next_token();
1849                         expect('(');
1850                         if (token.type != T_STRING_LITERAL) {
1851                                 parse_error_expected("while parsing assembler attribute",
1852                                                      T_STRING_LITERAL, NULL);
1853                                 eat_until_matching_token('(');
1854                                 break;
1855                         } else {
1856                                 parse_string_literals();
1857                         }
1858                         expect(')');
1859                         continue;
1860
1861                 case T_cdecl:     modifiers |= DM_CDECL;    break;
1862                 case T__fastcall: modifiers |= DM_FASTCALL; break;
1863                 case T__stdcall:  modifiers |= DM_STDCALL;  break;
1864
1865                 case T___thiscall:
1866                         /* TODO record modifier */
1867                         warningf(HERE, "Ignoring declaration modifier %K", &token);
1868                         break;
1869
1870 end_error:
1871                 default: return modifiers;
1872                 }
1873
1874                 next_token();
1875         }
1876 }
1877
1878 static designator_t *parse_designation(void)
1879 {
1880         designator_t *result = NULL;
1881         designator_t *last   = NULL;
1882
1883         while (true) {
1884                 designator_t *designator;
1885                 switch(token.type) {
1886                 case '[':
1887                         designator = allocate_ast_zero(sizeof(designator[0]));
1888                         designator->source_position = token.source_position;
1889                         next_token();
1890                         add_anchor_token(']');
1891                         designator->array_index = parse_constant_expression();
1892                         rem_anchor_token(']');
1893                         expect(']');
1894                         break;
1895                 case '.':
1896                         designator = allocate_ast_zero(sizeof(designator[0]));
1897                         designator->source_position = token.source_position;
1898                         next_token();
1899                         if (token.type != T_IDENTIFIER) {
1900                                 parse_error_expected("while parsing designator",
1901                                                      T_IDENTIFIER, NULL);
1902                                 return NULL;
1903                         }
1904                         designator->symbol = token.v.symbol;
1905                         next_token();
1906                         break;
1907                 default:
1908                         expect('=');
1909                         return result;
1910                 }
1911
1912                 assert(designator != NULL);
1913                 if (last != NULL) {
1914                         last->next = designator;
1915                 } else {
1916                         result = designator;
1917                 }
1918                 last = designator;
1919         }
1920 end_error:
1921         return NULL;
1922 }
1923
1924 static initializer_t *initializer_from_string(array_type_t *type,
1925                                               const string_t *const string)
1926 {
1927         /* TODO: check len vs. size of array type */
1928         (void) type;
1929
1930         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
1931         initializer->string.string = *string;
1932
1933         return initializer;
1934 }
1935
1936 static initializer_t *initializer_from_wide_string(array_type_t *const type,
1937                                                    wide_string_t *const string)
1938 {
1939         /* TODO: check len vs. size of array type */
1940         (void) type;
1941
1942         initializer_t *const initializer =
1943                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
1944         initializer->wide_string.string = *string;
1945
1946         return initializer;
1947 }
1948
1949 /**
1950  * Build an initializer from a given expression.
1951  */
1952 static initializer_t *initializer_from_expression(type_t *orig_type,
1953                                                   expression_t *expression)
1954 {
1955         /* TODO check that expression is a constant expression */
1956
1957         /* § 6.7.8.14/15 char array may be initialized by string literals */
1958         type_t *type           = skip_typeref(orig_type);
1959         type_t *expr_type_orig = expression->base.type;
1960         type_t *expr_type      = skip_typeref(expr_type_orig);
1961         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
1962                 array_type_t *const array_type   = &type->array;
1963                 type_t       *const element_type = skip_typeref(array_type->element_type);
1964
1965                 if (element_type->kind == TYPE_ATOMIC) {
1966                         atomic_type_kind_t akind = element_type->atomic.akind;
1967                         switch (expression->kind) {
1968                                 case EXPR_STRING_LITERAL:
1969                                         if (akind == ATOMIC_TYPE_CHAR
1970                                                         || akind == ATOMIC_TYPE_SCHAR
1971                                                         || akind == ATOMIC_TYPE_UCHAR) {
1972                                                 return initializer_from_string(array_type,
1973                                                         &expression->string.value);
1974                                         }
1975
1976                                 case EXPR_WIDE_STRING_LITERAL: {
1977                                         type_t *bare_wchar_type = skip_typeref(type_wchar_t);
1978                                         if (get_unqualified_type(element_type) == bare_wchar_type) {
1979                                                 return initializer_from_wide_string(array_type,
1980                                                         &expression->wide_string.value);
1981                                         }
1982                                 }
1983
1984                                 default:
1985                                         break;
1986                         }
1987                 }
1988         }
1989
1990         assign_error_t error = semantic_assign(type, expression);
1991         if (error == ASSIGN_ERROR_INCOMPATIBLE)
1992                 return NULL;
1993         report_assign_error(error, type, expression, "initializer",
1994                             &expression->base.source_position);
1995
1996         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
1997         result->value.value = create_implicit_cast(expression, type);
1998
1999         return result;
2000 }
2001
2002 /**
2003  * Checks if a given expression can be used as an constant initializer.
2004  */
2005 static bool is_initializer_constant(const expression_t *expression)
2006 {
2007         return is_constant_expression(expression)
2008                 || is_address_constant(expression);
2009 }
2010
2011 /**
2012  * Parses an scalar initializer.
2013  *
2014  * § 6.7.8.11; eat {} without warning
2015  */
2016 static initializer_t *parse_scalar_initializer(type_t *type,
2017                                                bool must_be_constant)
2018 {
2019         /* there might be extra {} hierarchies */
2020         int braces = 0;
2021         if (token.type == '{') {
2022                 warningf(HERE, "extra curly braces around scalar initializer");
2023                 do {
2024                         ++braces;
2025                         next_token();
2026                 } while (token.type == '{');
2027         }
2028
2029         expression_t *expression = parse_assignment_expression();
2030         if (must_be_constant && !is_initializer_constant(expression)) {
2031                 errorf(&expression->base.source_position,
2032                        "Initialisation expression '%E' is not constant\n",
2033                        expression);
2034         }
2035
2036         initializer_t *initializer = initializer_from_expression(type, expression);
2037
2038         if (initializer == NULL) {
2039                 errorf(&expression->base.source_position,
2040                        "expression '%E' (type '%T') doesn't match expected type '%T'",
2041                        expression, expression->base.type, type);
2042                 /* TODO */
2043                 return NULL;
2044         }
2045
2046         bool additional_warning_displayed = false;
2047         while (braces > 0) {
2048                 if (token.type == ',') {
2049                         next_token();
2050                 }
2051                 if (token.type != '}') {
2052                         if (!additional_warning_displayed) {
2053                                 warningf(HERE, "additional elements in scalar initializer");
2054                                 additional_warning_displayed = true;
2055                         }
2056                 }
2057                 eat_block();
2058                 braces--;
2059         }
2060
2061         return initializer;
2062 }
2063
2064 /**
2065  * An entry in the type path.
2066  */
2067 typedef struct type_path_entry_t type_path_entry_t;
2068 struct type_path_entry_t {
2069         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
2070         union {
2071                 size_t         index;          /**< For array types: the current index. */
2072                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
2073         } v;
2074 };
2075
2076 /**
2077  * A type path expression a position inside compound or array types.
2078  */
2079 typedef struct type_path_t type_path_t;
2080 struct type_path_t {
2081         type_path_entry_t *path;         /**< An flexible array containing the current path. */
2082         type_t            *top_type;     /**< type of the element the path points */
2083         size_t             max_index;    /**< largest index in outermost array */
2084 };
2085
2086 /**
2087  * Prints a type path for debugging.
2088  */
2089 static __attribute__((unused)) void debug_print_type_path(
2090                 const type_path_t *path)
2091 {
2092         size_t len = ARR_LEN(path->path);
2093
2094         for(size_t i = 0; i < len; ++i) {
2095                 const type_path_entry_t *entry = & path->path[i];
2096
2097                 type_t *type = skip_typeref(entry->type);
2098                 if (is_type_compound(type)) {
2099                         /* in gcc mode structs can have no members */
2100                         if (entry->v.compound_entry == NULL) {
2101                                 assert(i == len-1);
2102                                 continue;
2103                         }
2104                         fprintf(stderr, ".%s", entry->v.compound_entry->symbol->string);
2105                 } else if (is_type_array(type)) {
2106                         fprintf(stderr, "[%zu]", entry->v.index);
2107                 } else {
2108                         fprintf(stderr, "-INVALID-");
2109                 }
2110         }
2111         if (path->top_type != NULL) {
2112                 fprintf(stderr, "  (");
2113                 print_type(path->top_type);
2114                 fprintf(stderr, ")");
2115         }
2116 }
2117
2118 /**
2119  * Return the top type path entry, ie. in a path
2120  * (type).a.b returns the b.
2121  */
2122 static type_path_entry_t *get_type_path_top(const type_path_t *path)
2123 {
2124         size_t len = ARR_LEN(path->path);
2125         assert(len > 0);
2126         return &path->path[len-1];
2127 }
2128
2129 /**
2130  * Enlarge the type path by an (empty) element.
2131  */
2132 static type_path_entry_t *append_to_type_path(type_path_t *path)
2133 {
2134         size_t len = ARR_LEN(path->path);
2135         ARR_RESIZE(type_path_entry_t, path->path, len+1);
2136
2137         type_path_entry_t *result = & path->path[len];
2138         memset(result, 0, sizeof(result[0]));
2139         return result;
2140 }
2141
2142 /**
2143  * Descending into a sub-type. Enter the scope of the current
2144  * top_type.
2145  */
2146 static void descend_into_subtype(type_path_t *path)
2147 {
2148         type_t *orig_top_type = path->top_type;
2149         type_t *top_type      = skip_typeref(orig_top_type);
2150
2151         assert(is_type_compound(top_type) || is_type_array(top_type));
2152
2153         type_path_entry_t *top = append_to_type_path(path);
2154         top->type              = top_type;
2155
2156         if (is_type_compound(top_type)) {
2157                 declaration_t *declaration = top_type->compound.declaration;
2158                 declaration_t *entry       = declaration->scope.declarations;
2159                 top->v.compound_entry      = entry;
2160
2161                 if (entry != NULL) {
2162                         path->top_type         = entry->type;
2163                 } else {
2164                         path->top_type         = NULL;
2165                 }
2166         } else {
2167                 assert(is_type_array(top_type));
2168
2169                 top->v.index   = 0;
2170                 path->top_type = top_type->array.element_type;
2171         }
2172 }
2173
2174 /**
2175  * Pop an entry from the given type path, ie. returning from
2176  * (type).a.b to (type).a
2177  */
2178 static void ascend_from_subtype(type_path_t *path)
2179 {
2180         type_path_entry_t *top = get_type_path_top(path);
2181
2182         path->top_type = top->type;
2183
2184         size_t len = ARR_LEN(path->path);
2185         ARR_RESIZE(type_path_entry_t, path->path, len-1);
2186 }
2187
2188 /**
2189  * Pop entries from the given type path until the given
2190  * path level is reached.
2191  */
2192 static void ascend_to(type_path_t *path, size_t top_path_level)
2193 {
2194         size_t len = ARR_LEN(path->path);
2195
2196         while (len > top_path_level) {
2197                 ascend_from_subtype(path);
2198                 len = ARR_LEN(path->path);
2199         }
2200 }
2201
2202 static bool walk_designator(type_path_t *path, const designator_t *designator,
2203                             bool used_in_offsetof)
2204 {
2205         for( ; designator != NULL; designator = designator->next) {
2206                 type_path_entry_t *top       = get_type_path_top(path);
2207                 type_t            *orig_type = top->type;
2208
2209                 type_t *type = skip_typeref(orig_type);
2210
2211                 if (designator->symbol != NULL) {
2212                         symbol_t *symbol = designator->symbol;
2213                         if (!is_type_compound(type)) {
2214                                 if (is_type_valid(type)) {
2215                                         errorf(&designator->source_position,
2216                                                "'.%Y' designator used for non-compound type '%T'",
2217                                                symbol, orig_type);
2218                                 }
2219                                 goto failed;
2220                         }
2221
2222                         declaration_t *declaration = type->compound.declaration;
2223                         declaration_t *iter        = declaration->scope.declarations;
2224                         for( ; iter != NULL; iter = iter->next) {
2225                                 if (iter->symbol == symbol) {
2226                                         break;
2227                                 }
2228                         }
2229                         if (iter == NULL) {
2230                                 errorf(&designator->source_position,
2231                                        "'%T' has no member named '%Y'", orig_type, symbol);
2232                                 goto failed;
2233                         }
2234                         if (used_in_offsetof) {
2235                                 type_t *real_type = skip_typeref(iter->type);
2236                                 if (real_type->kind == TYPE_BITFIELD) {
2237                                         errorf(&designator->source_position,
2238                                                "offsetof designator '%Y' may not specify bitfield",
2239                                                symbol);
2240                                         goto failed;
2241                                 }
2242                         }
2243
2244                         top->type             = orig_type;
2245                         top->v.compound_entry = iter;
2246                         orig_type             = iter->type;
2247                 } else {
2248                         expression_t *array_index = designator->array_index;
2249                         assert(designator->array_index != NULL);
2250
2251                         if (!is_type_array(type)) {
2252                                 if (is_type_valid(type)) {
2253                                         errorf(&designator->source_position,
2254                                                "[%E] designator used for non-array type '%T'",
2255                                                array_index, orig_type);
2256                                 }
2257                                 goto failed;
2258                         }
2259                         if (!is_type_valid(array_index->base.type)) {
2260                                 goto failed;
2261                         }
2262
2263                         long index = fold_constant(array_index);
2264                         if (!used_in_offsetof) {
2265                                 if (index < 0) {
2266                                         errorf(&designator->source_position,
2267                                                "array index [%E] must be positive", array_index);
2268                                         goto failed;
2269                                 }
2270                                 if (type->array.size_constant == true) {
2271                                         long array_size = type->array.size;
2272                                         if (index >= array_size) {
2273                                                 errorf(&designator->source_position,
2274                                                        "designator [%E] (%d) exceeds array size %d",
2275                                                        array_index, index, array_size);
2276                                                 goto failed;
2277                                         }
2278                                 }
2279                         }
2280
2281                         top->type    = orig_type;
2282                         top->v.index = (size_t) index;
2283                         orig_type    = type->array.element_type;
2284                 }
2285                 path->top_type = orig_type;
2286
2287                 if (designator->next != NULL) {
2288                         descend_into_subtype(path);
2289                 }
2290         }
2291         return true;
2292
2293 failed:
2294         return false;
2295 }
2296
2297 static void advance_current_object(type_path_t *path, size_t top_path_level)
2298 {
2299         type_path_entry_t *top = get_type_path_top(path);
2300
2301         type_t *type = skip_typeref(top->type);
2302         if (is_type_union(type)) {
2303                 /* in unions only the first element is initialized */
2304                 top->v.compound_entry = NULL;
2305         } else if (is_type_struct(type)) {
2306                 declaration_t *entry = top->v.compound_entry;
2307
2308                 entry                 = entry->next;
2309                 top->v.compound_entry = entry;
2310                 if (entry != NULL) {
2311                         path->top_type = entry->type;
2312                         return;
2313                 }
2314         } else {
2315                 assert(is_type_array(type));
2316
2317                 top->v.index++;
2318
2319                 if (!type->array.size_constant || top->v.index < type->array.size) {
2320                         return;
2321                 }
2322         }
2323
2324         /* we're past the last member of the current sub-aggregate, try if we
2325          * can ascend in the type hierarchy and continue with another subobject */
2326         size_t len = ARR_LEN(path->path);
2327
2328         if (len > top_path_level) {
2329                 ascend_from_subtype(path);
2330                 advance_current_object(path, top_path_level);
2331         } else {
2332                 path->top_type = NULL;
2333         }
2334 }
2335
2336 /**
2337  * skip until token is found.
2338  */
2339 static void skip_until(int type)
2340 {
2341         while (token.type != type) {
2342                 if (token.type == T_EOF)
2343                         return;
2344                 next_token();
2345         }
2346 }
2347
2348 /**
2349  * skip any {...} blocks until a closing bracket is reached.
2350  */
2351 static void skip_initializers(void)
2352 {
2353         if (token.type == '{')
2354                 next_token();
2355
2356         while (token.type != '}') {
2357                 if (token.type == T_EOF)
2358                         return;
2359                 if (token.type == '{') {
2360                         eat_block();
2361                         continue;
2362                 }
2363                 next_token();
2364         }
2365 }
2366
2367 static initializer_t *create_empty_initializer(void)
2368 {
2369         static initializer_t empty_initializer
2370                 = { .list = { { INITIALIZER_LIST }, 0 } };
2371         return &empty_initializer;
2372 }
2373
2374 /**
2375  * Parse a part of an initialiser for a struct or union,
2376  */
2377 static initializer_t *parse_sub_initializer(type_path_t *path,
2378                 type_t *outer_type, size_t top_path_level,
2379                 parse_initializer_env_t *env)
2380 {
2381         if (token.type == '}') {
2382                 /* empty initializer */
2383                 return create_empty_initializer();
2384         }
2385
2386         type_t *orig_type = path->top_type;
2387         type_t *type      = NULL;
2388
2389         if (orig_type == NULL) {
2390                 /* We are initializing an empty compound. */
2391         } else {
2392                 type = skip_typeref(orig_type);
2393
2394                 /* we can't do usefull stuff if we didn't even parse the type. Skip the
2395                  * initializers in this case. */
2396                 if (!is_type_valid(type)) {
2397                         skip_initializers();
2398                         return create_empty_initializer();
2399                 }
2400         }
2401
2402         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2403
2404         while (true) {
2405                 designator_t *designator = NULL;
2406                 if (token.type == '.' || token.type == '[') {
2407                         designator = parse_designation();
2408                         goto finish_designator;
2409                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2410                         /* GNU-style designator ("identifier: value") */
2411                         designator = allocate_ast_zero(sizeof(designator[0]));
2412                         designator->source_position = token.source_position;
2413                         designator->symbol          = token.v.symbol;
2414                         eat(T_IDENTIFIER);
2415                         eat(':');
2416
2417 finish_designator:
2418                         /* reset path to toplevel, evaluate designator from there */
2419                         ascend_to(path, top_path_level);
2420                         if (!walk_designator(path, designator, false)) {
2421                                 /* can't continue after designation error */
2422                                 goto end_error;
2423                         }
2424
2425                         initializer_t *designator_initializer
2426                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2427                         designator_initializer->designator.designator = designator;
2428                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2429
2430                         orig_type = path->top_type;
2431                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2432                 }
2433
2434                 initializer_t *sub;
2435
2436                 if (token.type == '{') {
2437                         if (type != NULL && is_type_scalar(type)) {
2438                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2439                         } else {
2440                                 eat('{');
2441                                 if (type == NULL) {
2442                                         if (env->declaration != NULL) {
2443                                                 errorf(HERE, "extra brace group at end of initializer for '%Y'",
2444                                                        env->declaration->symbol);
2445                                         } else {
2446                                                 errorf(HERE, "extra brace group at end of initializer");
2447                                         }
2448                                 } else
2449                                         descend_into_subtype(path);
2450
2451                                 add_anchor_token('}');
2452                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2453                                                             env);
2454                                 rem_anchor_token('}');
2455
2456                                 if (type != NULL) {
2457                                         ascend_from_subtype(path);
2458                                         expect('}');
2459                                 } else {
2460                                         expect('}');
2461                                         goto error_parse_next;
2462                                 }
2463                         }
2464                 } else {
2465                         /* must be an expression */
2466                         expression_t *expression = parse_assignment_expression();
2467
2468                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2469                                 errorf(&expression->base.source_position,
2470                                        "Initialisation expression '%E' is not constant\n",
2471                                        expression);
2472                         }
2473
2474                         if (type == NULL) {
2475                                 /* we are already outside, ... */
2476                                 goto error_excess;
2477                         }
2478
2479                         /* handle { "string" } special case */
2480                         if ((expression->kind == EXPR_STRING_LITERAL
2481                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2482                                         && outer_type != NULL) {
2483                                 sub = initializer_from_expression(outer_type, expression);
2484                                 if (sub != NULL) {
2485                                         if (token.type == ',') {
2486                                                 next_token();
2487                                         }
2488                                         if (token.type != '}') {
2489                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2490                                                                  orig_type);
2491                                         }
2492                                         /* TODO: eat , ... */
2493                                         return sub;
2494                                 }
2495                         }
2496
2497                         /* descend into subtypes until expression matches type */
2498                         while (true) {
2499                                 orig_type = path->top_type;
2500                                 type      = skip_typeref(orig_type);
2501
2502                                 sub = initializer_from_expression(orig_type, expression);
2503                                 if (sub != NULL) {
2504                                         break;
2505                                 }
2506                                 if (!is_type_valid(type)) {
2507                                         goto end_error;
2508                                 }
2509                                 if (is_type_scalar(type)) {
2510                                         errorf(&expression->base.source_position,
2511                                                         "expression '%E' doesn't match expected type '%T'",
2512                                                         expression, orig_type);
2513                                         goto end_error;
2514                                 }
2515
2516                                 descend_into_subtype(path);
2517                         }
2518                 }
2519
2520                 /* update largest index of top array */
2521                 const type_path_entry_t *first      = &path->path[0];
2522                 type_t                  *first_type = first->type;
2523                 first_type                          = skip_typeref(first_type);
2524                 if (is_type_array(first_type)) {
2525                         size_t index = first->v.index;
2526                         if (index > path->max_index)
2527                                 path->max_index = index;
2528                 }
2529
2530                 if (type != NULL) {
2531                         /* append to initializers list */
2532                         ARR_APP1(initializer_t*, initializers, sub);
2533                 } else {
2534 error_excess:
2535                         if (env->declaration != NULL)
2536                                 warningf(HERE, "excess elements in struct initializer for '%Y'",
2537                                  env->declaration->symbol);
2538                         else
2539                                 warningf(HERE, "excess elements in struct initializer");
2540                 }
2541
2542 error_parse_next:
2543                 if (token.type == '}') {
2544                         break;
2545                 }
2546                 expect(',');
2547                 if (token.type == '}') {
2548                         break;
2549                 }
2550
2551                 if (type != NULL) {
2552                         /* advance to the next declaration if we are not at the end */
2553                         advance_current_object(path, top_path_level);
2554                         orig_type = path->top_type;
2555                         if (orig_type != NULL)
2556                                 type = skip_typeref(orig_type);
2557                         else
2558                                 type = NULL;
2559                 }
2560         }
2561
2562         size_t len  = ARR_LEN(initializers);
2563         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2564         initializer_t *result = allocate_ast_zero(size);
2565         result->kind          = INITIALIZER_LIST;
2566         result->list.len      = len;
2567         memcpy(&result->list.initializers, initializers,
2568                len * sizeof(initializers[0]));
2569
2570         DEL_ARR_F(initializers);
2571         ascend_to(path, top_path_level+1);
2572
2573         return result;
2574
2575 end_error:
2576         skip_initializers();
2577         DEL_ARR_F(initializers);
2578         ascend_to(path, top_path_level+1);
2579         return NULL;
2580 }
2581
2582 /**
2583  * Parses an initializer. Parsers either a compound literal
2584  * (env->declaration == NULL) or an initializer of a declaration.
2585  */
2586 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2587 {
2588         type_t        *type   = skip_typeref(env->type);
2589         initializer_t *result = NULL;
2590         size_t         max_index;
2591
2592         if (is_type_scalar(type)) {
2593                 result = parse_scalar_initializer(type, env->must_be_constant);
2594         } else if (token.type == '{') {
2595                 eat('{');
2596
2597                 type_path_t path;
2598                 memset(&path, 0, sizeof(path));
2599                 path.top_type = env->type;
2600                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2601
2602                 descend_into_subtype(&path);
2603
2604                 add_anchor_token('}');
2605                 result = parse_sub_initializer(&path, env->type, 1, env);
2606                 rem_anchor_token('}');
2607
2608                 max_index = path.max_index;
2609                 DEL_ARR_F(path.path);
2610
2611                 expect('}');
2612         } else {
2613                 /* parse_scalar_initializer() also works in this case: we simply
2614                  * have an expression without {} around it */
2615                 result = parse_scalar_initializer(type, env->must_be_constant);
2616         }
2617
2618         /* § 6.7.5 (22)  array initializers for arrays with unknown size determine
2619          * the array type size */
2620         if (is_type_array(type) && type->array.size_expression == NULL
2621                         && result != NULL) {
2622                 size_t size;
2623                 switch (result->kind) {
2624                 case INITIALIZER_LIST:
2625                         size = max_index + 1;
2626                         break;
2627
2628                 case INITIALIZER_STRING:
2629                         size = result->string.string.size;
2630                         break;
2631
2632                 case INITIALIZER_WIDE_STRING:
2633                         size = result->wide_string.string.size;
2634                         break;
2635
2636                 case INITIALIZER_DESIGNATOR:
2637                 case INITIALIZER_VALUE:
2638                         /* can happen for parse errors */
2639                         size = 0;
2640                         break;
2641
2642                 default:
2643                         internal_errorf(HERE, "invalid initializer type");
2644                 }
2645
2646                 expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2647                 cnst->base.type          = type_size_t;
2648                 cnst->conste.v.int_value = size;
2649
2650                 type_t *new_type = duplicate_type(type);
2651
2652                 new_type->array.size_expression = cnst;
2653                 new_type->array.size_constant   = true;
2654                 new_type->array.size            = size;
2655                 env->type = new_type;
2656         }
2657
2658         return result;
2659 end_error:
2660         return NULL;
2661 }
2662
2663 static declaration_t *append_declaration(declaration_t *declaration);
2664
2665 static declaration_t *parse_compound_type_specifier(bool is_struct)
2666 {
2667         gnu_attribute_t  *attributes = NULL;
2668         decl_modifiers_t  modifiers  = 0;
2669         if (is_struct) {
2670                 eat(T_struct);
2671         } else {
2672                 eat(T_union);
2673         }
2674
2675         symbol_t      *symbol      = NULL;
2676         declaration_t *declaration = NULL;
2677
2678         if (token.type == T___attribute__) {
2679                 modifiers |= parse_attributes(&attributes);
2680         }
2681
2682         if (token.type == T_IDENTIFIER) {
2683                 symbol = token.v.symbol;
2684                 next_token();
2685
2686                 namespace_t const namespc =
2687                         is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION;
2688                 declaration = get_declaration(symbol, namespc);
2689                 if (declaration != NULL) {
2690                         if (declaration->parent_scope != scope &&
2691                             (token.type == '{' || token.type == ';')) {
2692                                 declaration = NULL;
2693                         } else if (declaration->init.complete &&
2694                                    token.type == '{') {
2695                                 assert(symbol != NULL);
2696                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition at %P)",
2697                                        is_struct ? "struct" : "union", symbol,
2698                                        &declaration->source_position);
2699                                 declaration->scope.declarations = NULL;
2700                         }
2701                 }
2702         } else if (token.type != '{') {
2703                 if (is_struct) {
2704                         parse_error_expected("while parsing struct type specifier",
2705                                              T_IDENTIFIER, '{', NULL);
2706                 } else {
2707                         parse_error_expected("while parsing union type specifier",
2708                                              T_IDENTIFIER, '{', NULL);
2709                 }
2710
2711                 return NULL;
2712         }
2713
2714         if (declaration == NULL) {
2715                 declaration = allocate_declaration_zero();
2716                 declaration->namespc         =
2717                         (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
2718                 declaration->source_position = token.source_position;
2719                 declaration->symbol          = symbol;
2720                 declaration->parent_scope    = scope;
2721                 if (symbol != NULL) {
2722                         environment_push(declaration);
2723                 }
2724                 append_declaration(declaration);
2725         }
2726
2727         if (token.type == '{') {
2728                 declaration->init.complete = true;
2729
2730                 parse_compound_type_entries(declaration);
2731                 modifiers |= parse_attributes(&attributes);
2732         }
2733
2734         declaration->modifiers |= modifiers;
2735         return declaration;
2736 }
2737
2738 static void parse_enum_entries(type_t *const enum_type)
2739 {
2740         eat('{');
2741
2742         if (token.type == '}') {
2743                 next_token();
2744                 errorf(HERE, "empty enum not allowed");
2745                 return;
2746         }
2747
2748         add_anchor_token('}');
2749         do {
2750                 if (token.type != T_IDENTIFIER) {
2751                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
2752                         eat_block();
2753                         rem_anchor_token('}');
2754                         return;
2755                 }
2756
2757                 declaration_t *const entry = allocate_declaration_zero();
2758                 entry->storage_class   = STORAGE_CLASS_ENUM_ENTRY;
2759                 entry->type            = enum_type;
2760                 entry->symbol          = token.v.symbol;
2761                 entry->source_position = token.source_position;
2762                 next_token();
2763
2764                 if (token.type == '=') {
2765                         next_token();
2766                         expression_t *value = parse_constant_expression();
2767
2768                         value = create_implicit_cast(value, enum_type);
2769                         entry->init.enum_value = value;
2770
2771                         /* TODO semantic */
2772                 }
2773
2774                 record_declaration(entry, false);
2775
2776                 if (token.type != ',')
2777                         break;
2778                 next_token();
2779         } while (token.type != '}');
2780         rem_anchor_token('}');
2781
2782         expect('}');
2783
2784 end_error:
2785         ;
2786 }
2787
2788 static type_t *parse_enum_specifier(void)
2789 {
2790         gnu_attribute_t *attributes = NULL;
2791         declaration_t   *declaration;
2792         symbol_t        *symbol;
2793
2794         eat(T_enum);
2795         if (token.type == T_IDENTIFIER) {
2796                 symbol = token.v.symbol;
2797                 next_token();
2798
2799                 declaration = get_declaration(symbol, NAMESPACE_ENUM);
2800         } else if (token.type != '{') {
2801                 parse_error_expected("while parsing enum type specifier",
2802                                      T_IDENTIFIER, '{', NULL);
2803                 return NULL;
2804         } else {
2805                 declaration = NULL;
2806                 symbol      = NULL;
2807         }
2808
2809         if (declaration == NULL) {
2810                 declaration = allocate_declaration_zero();
2811                 declaration->namespc         = NAMESPACE_ENUM;
2812                 declaration->source_position = token.source_position;
2813                 declaration->symbol          = symbol;
2814                 declaration->parent_scope  = scope;
2815         }
2816
2817         type_t *const type      = allocate_type_zero(TYPE_ENUM, &declaration->source_position);
2818         type->enumt.declaration = declaration;
2819
2820         if (token.type == '{') {
2821                 if (declaration->init.complete) {
2822                         errorf(HERE, "multiple definitions of enum %Y", symbol);
2823                 }
2824                 if (symbol != NULL) {
2825                         environment_push(declaration);
2826                 }
2827                 append_declaration(declaration);
2828                 declaration->init.complete = true;
2829
2830                 parse_enum_entries(type);
2831                 parse_attributes(&attributes);
2832         }
2833
2834         return type;
2835 }
2836
2837 /**
2838  * if a symbol is a typedef to another type, return true
2839  */
2840 static bool is_typedef_symbol(symbol_t *symbol)
2841 {
2842         const declaration_t *const declaration =
2843                 get_declaration(symbol, NAMESPACE_NORMAL);
2844         return
2845                 declaration != NULL &&
2846                 declaration->storage_class == STORAGE_CLASS_TYPEDEF;
2847 }
2848
2849 static type_t *parse_typeof(void)
2850 {
2851         eat(T___typeof__);
2852
2853         type_t *type;
2854
2855         expect('(');
2856         add_anchor_token(')');
2857
2858         expression_t *expression  = NULL;
2859
2860 restart:
2861         switch(token.type) {
2862         case T___extension__:
2863                 /* This can be a prefix to a typename or an expression.  We simply eat
2864                  * it now. */
2865                 do {
2866                         next_token();
2867                 } while (token.type == T___extension__);
2868                 goto restart;
2869
2870         case T_IDENTIFIER:
2871                 if (is_typedef_symbol(token.v.symbol)) {
2872                         type = parse_typename();
2873                 } else {
2874                         expression = parse_expression();
2875                         type       = expression->base.type;
2876                 }
2877                 break;
2878
2879         TYPENAME_START
2880                 type = parse_typename();
2881                 break;
2882
2883         default:
2884                 expression = parse_expression();
2885                 type       = expression->base.type;
2886                 break;
2887         }
2888
2889         rem_anchor_token(')');
2890         expect(')');
2891
2892         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF, &expression->base.source_position);
2893         typeof_type->typeoft.expression  = expression;
2894         typeof_type->typeoft.typeof_type = type;
2895
2896         return typeof_type;
2897 end_error:
2898         return NULL;
2899 }
2900
2901 typedef enum specifiers_t {
2902         SPECIFIER_SIGNED    = 1 << 0,
2903         SPECIFIER_UNSIGNED  = 1 << 1,
2904         SPECIFIER_LONG      = 1 << 2,
2905         SPECIFIER_INT       = 1 << 3,
2906         SPECIFIER_DOUBLE    = 1 << 4,
2907         SPECIFIER_CHAR      = 1 << 5,
2908         SPECIFIER_SHORT     = 1 << 6,
2909         SPECIFIER_LONG_LONG = 1 << 7,
2910         SPECIFIER_FLOAT     = 1 << 8,
2911         SPECIFIER_BOOL      = 1 << 9,
2912         SPECIFIER_VOID      = 1 << 10,
2913         SPECIFIER_INT8      = 1 << 11,
2914         SPECIFIER_INT16     = 1 << 12,
2915         SPECIFIER_INT32     = 1 << 13,
2916         SPECIFIER_INT64     = 1 << 14,
2917         SPECIFIER_INT128    = 1 << 15,
2918         SPECIFIER_COMPLEX   = 1 << 16,
2919         SPECIFIER_IMAGINARY = 1 << 17,
2920 } specifiers_t;
2921
2922 static type_t *create_builtin_type(symbol_t *const symbol,
2923                                    type_t *const real_type)
2924 {
2925         type_t *type            = allocate_type_zero(TYPE_BUILTIN, &builtin_source_position);
2926         type->builtin.symbol    = symbol;
2927         type->builtin.real_type = real_type;
2928
2929         type_t *result = typehash_insert(type);
2930         if (type != result) {
2931                 free_type(type);
2932         }
2933
2934         return result;
2935 }
2936
2937 static type_t *get_typedef_type(symbol_t *symbol)
2938 {
2939         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
2940         if (declaration == NULL ||
2941            declaration->storage_class != STORAGE_CLASS_TYPEDEF)
2942                 return NULL;
2943
2944         type_t *type               = allocate_type_zero(TYPE_TYPEDEF, &declaration->source_position);
2945         type->typedeft.declaration = declaration;
2946
2947         return type;
2948 }
2949
2950 /**
2951  * check for the allowed MS alignment values.
2952  */
2953 static bool check_alignment_value(long long intvalue)
2954 {
2955         if (intvalue < 1 || intvalue > 8192) {
2956                 errorf(HERE, "illegal alignment value");
2957                 return false;
2958         }
2959         unsigned v = (unsigned)intvalue;
2960         for(unsigned i = 1; i <= 8192; i += i) {
2961                 if (i == v)
2962                         return true;
2963         }
2964         errorf(HERE, "alignment must be power of two");
2965         return false;
2966 }
2967
2968 #define DET_MOD(name, tag) do { \
2969         if (*modifiers & tag) warningf(HERE, #name " used more than once"); \
2970         *modifiers |= tag; \
2971 } while (0)
2972
2973 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
2974 {
2975         decl_modifiers_t *modifiers = &specifiers->modifiers;
2976
2977         while (true) {
2978                 if (token.type == T_restrict) {
2979                         next_token();
2980                         DET_MOD(restrict, DM_RESTRICT);
2981                         goto end_loop;
2982                 } else if (token.type != T_IDENTIFIER)
2983                         break;
2984                 symbol_t *symbol = token.v.symbol;
2985                 if (symbol == sym_align) {
2986                         next_token();
2987                         expect('(');
2988                         if (token.type != T_INTEGER)
2989                                 goto end_error;
2990                         if (check_alignment_value(token.v.intvalue)) {
2991                                 if (specifiers->alignment != 0)
2992                                         warningf(HERE, "align used more than once");
2993                                 specifiers->alignment = (unsigned char)token.v.intvalue;
2994                         }
2995                         next_token();
2996                         expect(')');
2997                 } else if (symbol == sym_allocate) {
2998                         next_token();
2999                         expect('(');
3000                         if (token.type != T_IDENTIFIER)
3001                                 goto end_error;
3002                         (void)token.v.symbol;
3003                         expect(')');
3004                 } else if (symbol == sym_dllimport) {
3005                         next_token();
3006                         DET_MOD(dllimport, DM_DLLIMPORT);
3007                 } else if (symbol == sym_dllexport) {
3008                         next_token();
3009                         DET_MOD(dllexport, DM_DLLEXPORT);
3010                 } else if (symbol == sym_thread) {
3011                         next_token();
3012                         DET_MOD(thread, DM_THREAD);
3013                 } else if (symbol == sym_naked) {
3014                         next_token();
3015                         DET_MOD(naked, DM_NAKED);
3016                 } else if (symbol == sym_noinline) {
3017                         next_token();
3018                         DET_MOD(noinline, DM_NOINLINE);
3019                 } else if (symbol == sym_noreturn) {
3020                         next_token();
3021                         DET_MOD(noreturn, DM_NORETURN);
3022                 } else if (symbol == sym_nothrow) {
3023                         next_token();
3024                         DET_MOD(nothrow, DM_NOTHROW);
3025                 } else if (symbol == sym_novtable) {
3026                         next_token();
3027                         DET_MOD(novtable, DM_NOVTABLE);
3028                 } else if (symbol == sym_property) {
3029                         next_token();
3030                         expect('(');
3031                         for(;;) {
3032                                 bool is_get = false;
3033                                 if (token.type != T_IDENTIFIER)
3034                                         goto end_error;
3035                                 if (token.v.symbol == sym_get) {
3036                                         is_get = true;
3037                                 } else if (token.v.symbol == sym_put) {
3038                                 } else {
3039                                         errorf(HERE, "Bad property name '%Y'", token.v.symbol);
3040                                         goto end_error;
3041                                 }
3042                                 next_token();
3043                                 expect('=');
3044                                 if (token.type != T_IDENTIFIER)
3045                                         goto end_error;
3046                                 if (is_get) {
3047                                         if (specifiers->get_property_sym != NULL) {
3048                                                 errorf(HERE, "get property name already specified");
3049                                         } else {
3050                                                 specifiers->get_property_sym = token.v.symbol;
3051                                         }
3052                                 } else {
3053                                         if (specifiers->put_property_sym != NULL) {
3054                                                 errorf(HERE, "put property name already specified");
3055                                         } else {
3056                                                 specifiers->put_property_sym = token.v.symbol;
3057                                         }
3058                                 }
3059                                 next_token();
3060                                 if (token.type == ',') {
3061                                         next_token();
3062                                         continue;
3063                                 }
3064                                 break;
3065                         }
3066                         expect(')');
3067                 } else if (symbol == sym_selectany) {
3068                         next_token();
3069                         DET_MOD(selectany, DM_SELECTANY);
3070                 } else if (symbol == sym_uuid) {
3071                         next_token();
3072                         expect('(');
3073                         if (token.type != T_STRING_LITERAL)
3074                                 goto end_error;
3075                         next_token();
3076                         expect(')');
3077                 } else if (symbol == sym_deprecated) {
3078                         next_token();
3079                         if (specifiers->deprecated != 0)
3080                                 warningf(HERE, "deprecated used more than once");
3081                         specifiers->deprecated = 1;
3082                         if (token.type == '(') {
3083                                 next_token();
3084                                 if (token.type == T_STRING_LITERAL) {
3085                                         specifiers->deprecated_string = token.v.string.begin;
3086                                         next_token();
3087                                 } else {
3088                                         errorf(HERE, "string literal expected");
3089                                 }
3090                                 expect(')');
3091                         }
3092                 } else if (symbol == sym_noalias) {
3093                         next_token();
3094                         DET_MOD(noalias, DM_NOALIAS);
3095                 } else {
3096                         warningf(HERE, "Unknown modifier %Y ignored", token.v.symbol);
3097                         next_token();
3098                         if (token.type == '(')
3099                                 skip_until(')');
3100                 }
3101 end_loop:
3102                 if (token.type == ',')
3103                         next_token();
3104         }
3105 end_error:
3106         return;
3107 }
3108
3109 static declaration_t *create_error_declaration(symbol_t *symbol, storage_class_tag_t storage_class)
3110 {
3111         declaration_t *const decl    = allocate_declaration_zero();
3112         decl->source_position        = *HERE;
3113         decl->declared_storage_class = storage_class;
3114         decl->storage_class          =
3115                 storage_class != STORAGE_CLASS_NONE || scope == global_scope ?
3116                         storage_class : STORAGE_CLASS_AUTO;
3117         decl->symbol                 = symbol;
3118         decl->implicit               = true;
3119         record_declaration(decl, false);
3120         return decl;
3121 }
3122
3123 /**
3124  * Finish the construction of a struct type by calculating
3125  * its size, offsets, alignment.
3126  */
3127 static void finish_struct_type(compound_type_t *type) {
3128         if (type->declaration == NULL)
3129                 return;
3130         declaration_t *struct_decl = type->declaration;
3131         if (! struct_decl->init.complete)
3132                 return;
3133
3134         il_size_t      size      = 0;
3135         il_size_t      new_size;
3136         il_alignment_t alignment = 1;
3137         bool           need_pad  = false;
3138
3139         declaration_t *entry = struct_decl->scope.declarations;
3140         for (; entry != NULL; entry = entry->next) {
3141                 if (entry->namespc != NAMESPACE_NORMAL)
3142                         continue;
3143
3144                 type_t         *m_type      = skip_typeref(entry->type);
3145                 il_alignment_t  m_alignment = m_type->base.alignment;
3146
3147                 new_size = (size + m_alignment - 1) & -m_alignment;
3148                 if (m_alignment > alignment)
3149                         alignment = m_alignment;
3150                 if (new_size > size)
3151                         need_pad = true;
3152                 entry->offset = new_size;
3153                 size = new_size + m_type->base.size;
3154         }
3155         if (type->base.alignment != 0) {
3156                 alignment = type->base.alignment;
3157         }
3158
3159         new_size = (size + alignment - 1) & -alignment;
3160         if (new_size > size)
3161                 need_pad = true;
3162
3163         if (warning.padded && need_pad) {
3164                 warningf(&struct_decl->source_position,
3165                         "'%#T' needs padding", type, struct_decl->symbol);
3166         }
3167         if (warning.packed && !need_pad) {
3168                 warningf(&struct_decl->source_position,
3169                         "superfluous packed attribute on '%#T'",
3170                         type, struct_decl->symbol);
3171         }
3172
3173         type->base.size      = new_size;
3174         type->base.alignment = alignment;
3175 }
3176
3177 /**
3178  * Finish the construction of an union type by calculating
3179  * its size and alignment.
3180  */
3181 static void finish_union_type(compound_type_t *type) {
3182         if (type->declaration == NULL)
3183                 return;
3184         declaration_t *union_decl = type->declaration;
3185         if (! union_decl->init.complete)
3186                 return;
3187
3188         il_size_t      size      = 0;
3189         il_alignment_t alignment = 1;
3190
3191         declaration_t *entry = union_decl->scope.declarations;
3192         for (; entry != NULL; entry = entry->next) {
3193                 if (entry->namespc != NAMESPACE_NORMAL)
3194                         continue;
3195
3196                 type_t *m_type = skip_typeref(entry->type);
3197
3198                 entry->offset = 0;
3199                 if (m_type->base.size > size)
3200                         size = m_type->base.size;
3201                 if (m_type->base.alignment > alignment)
3202                         alignment = m_type->base.alignment;
3203         }
3204         if (type->base.alignment != 0) {
3205                 alignment = type->base.alignment;
3206         }
3207         size = (size + alignment - 1) & -alignment;
3208         type->base.size      = size;
3209         type->base.alignment = alignment;
3210 }
3211
3212 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
3213 {
3214         type_t            *type            = NULL;
3215         type_qualifiers_t  qualifiers      = TYPE_QUALIFIER_NONE;
3216         type_modifiers_t   modifiers       = TYPE_MODIFIER_NONE;
3217         unsigned           type_specifiers = 0;
3218         bool               newtype         = false;
3219         bool               saw_error       = false;
3220
3221         specifiers->source_position = token.source_position;
3222
3223         while (true) {
3224                 specifiers->modifiers
3225                         |= parse_attributes(&specifiers->gnu_attributes);
3226                 if (specifiers->modifiers & DM_TRANSPARENT_UNION)
3227                         modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3228
3229                 switch(token.type) {
3230
3231                 /* storage class */
3232 #define MATCH_STORAGE_CLASS(token, class)                                  \
3233                 case token:                                                        \
3234                         if (specifiers->declared_storage_class != STORAGE_CLASS_NONE) { \
3235                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3236                         }                                                              \
3237                         specifiers->declared_storage_class = class;                    \
3238                         next_token();                                                  \
3239                         break;
3240
3241                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3242                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3243                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3244                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3245                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3246
3247                 case T__declspec:
3248                         next_token();
3249                         expect('(');
3250                         add_anchor_token(')');
3251                         parse_microsoft_extended_decl_modifier(specifiers);
3252                         rem_anchor_token(')');
3253                         expect(')');
3254                         break;
3255
3256                 case T___thread:
3257                         switch (specifiers->declared_storage_class) {
3258                         case STORAGE_CLASS_NONE:
3259                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD;
3260                                 break;
3261
3262                         case STORAGE_CLASS_EXTERN:
3263                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_EXTERN;
3264                                 break;
3265
3266                         case STORAGE_CLASS_STATIC:
3267                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_STATIC;
3268                                 break;
3269
3270                         default:
3271                                 errorf(HERE, "multiple storage classes in declaration specifiers");
3272                                 break;
3273                         }
3274                         next_token();
3275                         break;
3276
3277                 /* type qualifiers */
3278 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3279                 case token:                                                     \
3280                         qualifiers |= qualifier;                                    \
3281                         next_token();                                               \
3282                         break
3283
3284                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3285                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3286                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3287                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3288                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3289                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3290                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3291                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3292
3293                 case T___extension__:
3294                         /* TODO */
3295                         next_token();
3296                         break;
3297
3298                 /* type specifiers */
3299 #define MATCH_SPECIFIER(token, specifier, name)                         \
3300                 case token:                                                     \
3301                         next_token();                                               \
3302                         if (type_specifiers & specifier) {                           \
3303                                 errorf(HERE, "multiple " name " type specifiers given"); \
3304                         } else {                                                    \
3305                                 type_specifiers |= specifier;                           \
3306                         }                                                           \
3307                         break
3308
3309                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3310                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3311                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3312                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3313                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3314                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3315                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3316                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3317                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3318                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3319                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3320                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3321                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3322                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3323                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3324                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3325
3326                 case T__forceinline:
3327                         /* only in microsoft mode */
3328                         specifiers->modifiers |= DM_FORCEINLINE;
3329                         /* FALLTHROUGH */
3330
3331                 case T_inline:
3332                         next_token();
3333                         specifiers->is_inline = true;
3334                         break;
3335
3336                 case T_long:
3337                         next_token();
3338                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3339                                 errorf(HERE, "multiple type specifiers given");
3340                         } else if (type_specifiers & SPECIFIER_LONG) {
3341                                 type_specifiers |= SPECIFIER_LONG_LONG;
3342                         } else {
3343                                 type_specifiers |= SPECIFIER_LONG;
3344                         }
3345                         break;
3346
3347                 case T_struct: {
3348                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT, HERE);
3349
3350                         type->compound.declaration = parse_compound_type_specifier(true);
3351                         finish_struct_type(&type->compound);
3352                         break;
3353                 }
3354                 case T_union: {
3355                         type = allocate_type_zero(TYPE_COMPOUND_UNION, HERE);
3356                         type->compound.declaration = parse_compound_type_specifier(false);
3357                         if (type->compound.declaration->modifiers & DM_TRANSPARENT_UNION)
3358                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3359                         break;
3360                         finish_union_type(&type->compound);
3361                 }
3362                 case T_enum:
3363                         type = parse_enum_specifier();
3364                         break;
3365                 case T___typeof__:
3366                         type = parse_typeof();
3367                         break;
3368                 case T___builtin_va_list:
3369                         type = duplicate_type(type_valist);
3370                         next_token();
3371                         break;
3372
3373                 case T_IDENTIFIER: {
3374                         /* only parse identifier if we haven't found a type yet */
3375                         if (type != NULL || type_specifiers != 0) {
3376                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
3377                                  * declaration, so it doesn't generate errors about expecting '(' or
3378                                  * '{' later on. */
3379                                 switch (look_ahead(1)->type) {
3380                                         STORAGE_CLASSES
3381                                         TYPE_SPECIFIERS
3382                                         case T_const:
3383                                         case T_restrict:
3384                                         case T_volatile:
3385                                         case T_inline:
3386                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
3387                                         case T_IDENTIFIER:
3388                                         case '*':
3389                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
3390                                                 next_token();
3391                                                 continue;
3392
3393                                         default:
3394                                                 goto finish_specifiers;
3395                                 }
3396                         }
3397
3398                         type_t *const typedef_type = get_typedef_type(token.v.symbol);
3399                         if (typedef_type == NULL) {
3400                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3401                                  * declaration, so it doesn't generate 'implicit int' followed by more
3402                                  * errors later on. */
3403                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3404                                 switch (la1_type) {
3405                                         DECLARATION_START
3406                                         case T_IDENTIFIER:
3407                                         case '*': {
3408                                                 errorf(HERE, "%K does not name a type", &token);
3409
3410                                                 declaration_t *const decl =
3411                                                         create_error_declaration(token.v.symbol, STORAGE_CLASS_TYPEDEF);
3412
3413                                                 type = allocate_type_zero(TYPE_TYPEDEF, HERE);
3414                                                 type->typedeft.declaration = decl;
3415
3416                                                 next_token();
3417                                                 saw_error = true;
3418                                                 if (la1_type == '*')
3419                                                         goto finish_specifiers;
3420                                                 continue;
3421                                         }
3422
3423                                         default:
3424                                                 goto finish_specifiers;
3425                                 }
3426                         }
3427
3428                         next_token();
3429                         type = typedef_type;
3430                         break;
3431                 }
3432
3433                 /* function specifier */
3434                 default:
3435                         goto finish_specifiers;
3436                 }
3437         }
3438
3439 finish_specifiers:
3440         if (type == NULL || (saw_error && type_specifiers != 0)) {
3441                 atomic_type_kind_t atomic_type;
3442
3443                 /* match valid basic types */
3444                 switch(type_specifiers) {
3445                 case SPECIFIER_VOID:
3446                         atomic_type = ATOMIC_TYPE_VOID;
3447                         break;
3448                 case SPECIFIER_CHAR:
3449                         atomic_type = ATOMIC_TYPE_CHAR;
3450                         break;
3451                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3452                         atomic_type = ATOMIC_TYPE_SCHAR;
3453                         break;
3454                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3455                         atomic_type = ATOMIC_TYPE_UCHAR;
3456                         break;
3457                 case SPECIFIER_SHORT:
3458                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3459                 case SPECIFIER_SHORT | SPECIFIER_INT:
3460                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3461                         atomic_type = ATOMIC_TYPE_SHORT;
3462                         break;
3463                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3464                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3465                         atomic_type = ATOMIC_TYPE_USHORT;
3466                         break;
3467                 case SPECIFIER_INT:
3468                 case SPECIFIER_SIGNED:
3469                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3470                         atomic_type = ATOMIC_TYPE_INT;
3471                         break;
3472                 case SPECIFIER_UNSIGNED:
3473                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3474                         atomic_type = ATOMIC_TYPE_UINT;
3475                         break;
3476                 case SPECIFIER_LONG:
3477                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3478                 case SPECIFIER_LONG | SPECIFIER_INT:
3479                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3480                         atomic_type = ATOMIC_TYPE_LONG;
3481                         break;
3482                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3483                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3484                         atomic_type = ATOMIC_TYPE_ULONG;
3485                         break;
3486
3487                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3488                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3489                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3490                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3491                         | SPECIFIER_INT:
3492                         atomic_type = ATOMIC_TYPE_LONGLONG;
3493                         goto warn_about_long_long;
3494
3495                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3496                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3497                         | SPECIFIER_INT:
3498                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3499 warn_about_long_long:
3500                         if (warning.long_long) {
3501                                 warningf(&specifiers->source_position,
3502                                          "ISO C90 does not support 'long long'");
3503                         }
3504                         break;
3505
3506                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3507                         atomic_type = unsigned_int8_type_kind;
3508                         break;
3509
3510                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3511                         atomic_type = unsigned_int16_type_kind;
3512                         break;
3513
3514                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3515                         atomic_type = unsigned_int32_type_kind;
3516                         break;
3517
3518                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3519                         atomic_type = unsigned_int64_type_kind;
3520                         break;
3521
3522                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3523                         atomic_type = unsigned_int128_type_kind;
3524                         break;
3525
3526                 case SPECIFIER_INT8:
3527                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3528                         atomic_type = int8_type_kind;
3529                         break;
3530
3531                 case SPECIFIER_INT16:
3532                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3533                         atomic_type = int16_type_kind;
3534                         break;
3535
3536                 case SPECIFIER_INT32:
3537                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3538                         atomic_type = int32_type_kind;
3539                         break;
3540
3541                 case SPECIFIER_INT64:
3542                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3543                         atomic_type = int64_type_kind;
3544                         break;
3545
3546                 case SPECIFIER_INT128:
3547                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3548                         atomic_type = int128_type_kind;
3549                         break;
3550
3551                 case SPECIFIER_FLOAT:
3552                         atomic_type = ATOMIC_TYPE_FLOAT;
3553                         break;
3554                 case SPECIFIER_DOUBLE:
3555                         atomic_type = ATOMIC_TYPE_DOUBLE;
3556                         break;
3557                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3558                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3559                         break;
3560                 case SPECIFIER_BOOL:
3561                         atomic_type = ATOMIC_TYPE_BOOL;
3562                         break;
3563                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3564                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3565                         atomic_type = ATOMIC_TYPE_FLOAT;
3566                         break;
3567                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3568                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3569                         atomic_type = ATOMIC_TYPE_DOUBLE;
3570                         break;
3571                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3572                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3573                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3574                         break;
3575                 default:
3576                         /* invalid specifier combination, give an error message */
3577                         if (type_specifiers == 0) {
3578                                 if (saw_error) {
3579                                         specifiers->type = type_error_type;
3580                                         return;
3581                                 }
3582
3583                                 if (!strict_mode) {
3584                                         if (warning.implicit_int) {
3585                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
3586                                         }
3587                                         atomic_type = ATOMIC_TYPE_INT;
3588                                         break;
3589                                 } else {
3590                                         errorf(HERE, "no type specifiers given in declaration");
3591                                 }
3592                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
3593                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
3594                                 errorf(HERE, "signed and unsigned specifiers given");
3595                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
3596                                 errorf(HERE, "only integer types can be signed or unsigned");
3597                         } else {
3598                                 errorf(HERE, "multiple datatypes in declaration");
3599                         }
3600                         atomic_type = ATOMIC_TYPE_INVALID;
3601                 }
3602
3603                 if (type_specifiers & SPECIFIER_COMPLEX &&
3604                    atomic_type != ATOMIC_TYPE_INVALID) {
3605                         type                = allocate_type_zero(TYPE_COMPLEX, &builtin_source_position);
3606                         type->complex.akind = atomic_type;
3607                 } else if (type_specifiers & SPECIFIER_IMAGINARY &&
3608                           atomic_type != ATOMIC_TYPE_INVALID) {
3609                         type                  = allocate_type_zero(TYPE_IMAGINARY, &builtin_source_position);
3610                         type->imaginary.akind = atomic_type;
3611                 } else {
3612                         type               = allocate_type_zero(TYPE_ATOMIC, &builtin_source_position);
3613                         type->atomic.akind = atomic_type;
3614                 }
3615                 newtype = true;
3616         } else if (type_specifiers != 0) {
3617                 errorf(HERE, "multiple datatypes in declaration");
3618         }
3619
3620         /* FIXME: check type qualifiers here */
3621
3622         type->base.qualifiers = qualifiers;
3623         type->base.modifiers  = modifiers;
3624
3625         type_t *result = typehash_insert(type);
3626         if (newtype && result != type) {
3627                 free_type(type);
3628         }
3629
3630         specifiers->type = result;
3631 end_error:
3632         return;
3633 }
3634
3635 static type_qualifiers_t parse_type_qualifiers(void)
3636 {
3637         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
3638
3639         while (true) {
3640                 switch(token.type) {
3641                 /* type qualifiers */
3642                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3643                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3644                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3645                 /* microsoft extended type modifiers */
3646                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3647                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3648                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3649                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3650                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3651
3652                 default:
3653                         return qualifiers;
3654                 }
3655         }
3656 }
3657
3658 static declaration_t *parse_identifier_list(void)
3659 {
3660         declaration_t *declarations     = NULL;
3661         declaration_t *last_declaration = NULL;
3662         do {
3663                 declaration_t *const declaration = allocate_declaration_zero();
3664                 declaration->type            = NULL; /* a K&R parameter list has no types, yet */
3665                 declaration->source_position = token.source_position;
3666                 declaration->symbol          = token.v.symbol;
3667                 next_token();
3668
3669                 if (last_declaration != NULL) {
3670                         last_declaration->next = declaration;
3671                 } else {
3672                         declarations = declaration;
3673                 }
3674                 last_declaration = declaration;
3675
3676                 if (token.type != ',') {
3677                         break;
3678                 }
3679                 next_token();
3680         } while (token.type == T_IDENTIFIER);
3681
3682         return declarations;
3683 }
3684
3685 static type_t *automatic_type_conversion(type_t *orig_type);
3686
3687 static void semantic_parameter(declaration_t *declaration)
3688 {
3689         /* TODO: improve error messages */
3690         source_position_t const* const pos = &declaration->source_position;
3691
3692         switch (declaration->declared_storage_class) {
3693                 case STORAGE_CLASS_TYPEDEF:
3694                         errorf(pos, "typedef not allowed in parameter list");
3695                         break;
3696
3697                 /* Allowed storage classes */
3698                 case STORAGE_CLASS_NONE:
3699                 case STORAGE_CLASS_REGISTER:
3700                         break;
3701
3702                 default:
3703                         errorf(pos, "parameter may only have none or register storage class");
3704                         break;
3705         }
3706
3707         type_t *const orig_type = declaration->type;
3708         /* §6.7.5.3(7): Array as last part of a parameter type is just syntactic
3709          * sugar.  Turn it into a pointer.
3710          * §6.7.5.3(8): A declaration of a parameter as ``function returning type''
3711          * shall be adjusted to ``pointer to function returning type'', as in 6.3.2.1.
3712          */
3713         type_t *const type = automatic_type_conversion(orig_type);
3714         declaration->type = type;
3715
3716         if (is_type_incomplete(skip_typeref(type))) {
3717                 errorf(pos, "parameter '%#T' is of incomplete type",
3718                        orig_type, declaration->symbol);
3719         }
3720 }
3721
3722 static declaration_t *parse_parameter(void)
3723 {
3724         declaration_specifiers_t specifiers;
3725         memset(&specifiers, 0, sizeof(specifiers));
3726
3727         parse_declaration_specifiers(&specifiers);
3728
3729         declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/true);
3730
3731         return declaration;
3732 }
3733
3734 static declaration_t *parse_parameters(function_type_t *type)
3735 {
3736         declaration_t *declarations = NULL;
3737
3738         eat('(');
3739         add_anchor_token(')');
3740         int saved_comma_state = save_and_reset_anchor_state(',');
3741
3742         if (token.type == T_IDENTIFIER &&
3743             !is_typedef_symbol(token.v.symbol)) {
3744                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
3745                 if (la1_type == ',' || la1_type == ')') {
3746                         type->kr_style_parameters = true;
3747                         declarations = parse_identifier_list();
3748                         goto parameters_finished;
3749                 }
3750         }
3751
3752         if (token.type == ')') {
3753                 type->unspecified_parameters = 1;
3754                 goto parameters_finished;
3755         }
3756
3757         declaration_t        *declaration;
3758         declaration_t        *last_declaration = NULL;
3759         function_parameter_t *parameter;
3760         function_parameter_t *last_parameter = NULL;
3761
3762         while (true) {
3763                 switch(token.type) {
3764                 case T_DOTDOTDOT:
3765                         next_token();
3766                         type->variadic = 1;
3767                         goto parameters_finished;
3768
3769                 case T_IDENTIFIER:
3770                 case T___extension__:
3771                 DECLARATION_START
3772                         declaration = parse_parameter();
3773
3774                         /* func(void) is not a parameter */
3775                         if (last_parameter == NULL
3776                                         && token.type == ')'
3777                                         && declaration->symbol == NULL
3778                                         && skip_typeref(declaration->type) == type_void) {
3779                                 goto parameters_finished;
3780                         }
3781                         semantic_parameter(declaration);
3782
3783                         parameter       = obstack_alloc(type_obst, sizeof(parameter[0]));
3784                         memset(parameter, 0, sizeof(parameter[0]));
3785                         parameter->type = declaration->type;
3786
3787                         if (last_parameter != NULL) {
3788                                 last_declaration->next = declaration;
3789                                 last_parameter->next   = parameter;
3790                         } else {
3791                                 type->parameters = parameter;
3792                                 declarations     = declaration;
3793                         }
3794                         last_parameter   = parameter;
3795                         last_declaration = declaration;
3796                         break;
3797
3798                 default:
3799                         goto parameters_finished;
3800                 }
3801                 if (token.type != ',') {
3802                         goto parameters_finished;
3803                 }
3804                 next_token();
3805         }
3806
3807
3808 parameters_finished:
3809         rem_anchor_token(')');
3810         expect(')');
3811
3812         restore_anchor_state(',', saved_comma_state);
3813         return declarations;
3814
3815 end_error:
3816         restore_anchor_state(',', saved_comma_state);
3817         return NULL;
3818 }
3819
3820 typedef enum construct_type_kind_t {
3821         CONSTRUCT_INVALID,
3822         CONSTRUCT_POINTER,
3823         CONSTRUCT_FUNCTION,
3824         CONSTRUCT_ARRAY
3825 } construct_type_kind_t;
3826
3827 typedef struct construct_type_t construct_type_t;
3828 struct construct_type_t {
3829         construct_type_kind_t  kind;
3830         construct_type_t      *next;
3831 };
3832
3833 typedef struct parsed_pointer_t parsed_pointer_t;
3834 struct parsed_pointer_t {
3835         construct_type_t  construct_type;
3836         type_qualifiers_t type_qualifiers;
3837 };
3838
3839 typedef struct construct_function_type_t construct_function_type_t;
3840 struct construct_function_type_t {
3841         construct_type_t  construct_type;
3842         type_t           *function_type;
3843 };
3844
3845 typedef struct parsed_array_t parsed_array_t;
3846 struct parsed_array_t {
3847         construct_type_t  construct_type;
3848         type_qualifiers_t type_qualifiers;
3849         bool              is_static;
3850         bool              is_variable;
3851         expression_t     *size;
3852 };
3853
3854 typedef struct construct_base_type_t construct_base_type_t;
3855 struct construct_base_type_t {
3856         construct_type_t  construct_type;
3857         type_t           *type;
3858 };
3859
3860 static construct_type_t *parse_pointer_declarator(void)
3861 {
3862         eat('*');
3863
3864         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
3865         memset(pointer, 0, sizeof(pointer[0]));
3866         pointer->construct_type.kind = CONSTRUCT_POINTER;
3867         pointer->type_qualifiers     = parse_type_qualifiers();
3868
3869         return (construct_type_t*) pointer;
3870 }
3871
3872 static construct_type_t *parse_array_declarator(void)
3873 {
3874         eat('[');
3875         add_anchor_token(']');
3876
3877         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
3878         memset(array, 0, sizeof(array[0]));
3879         array->construct_type.kind = CONSTRUCT_ARRAY;
3880
3881         if (token.type == T_static) {
3882                 array->is_static = true;
3883                 next_token();
3884         }
3885
3886         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
3887         if (type_qualifiers != 0) {
3888                 if (token.type == T_static) {
3889                         array->is_static = true;
3890                         next_token();
3891                 }
3892         }
3893         array->type_qualifiers = type_qualifiers;
3894
3895         if (token.type == '*' && look_ahead(1)->type == ']') {
3896                 array->is_variable = true;
3897                 next_token();
3898         } else if (token.type != ']') {
3899                 array->size = parse_assignment_expression();
3900         }
3901
3902         rem_anchor_token(']');
3903         expect(']');
3904
3905         return (construct_type_t*) array;
3906 end_error:
3907         return NULL;
3908 }
3909
3910 static construct_type_t *parse_function_declarator(declaration_t *declaration)
3911 {
3912         type_t *type;
3913         if (declaration != NULL) {
3914                 type = allocate_type_zero(TYPE_FUNCTION, &declaration->source_position);
3915
3916                 unsigned mask = declaration->modifiers & (DM_CDECL|DM_STDCALL|DM_FASTCALL|DM_THISCALL);
3917
3918                 if (mask & (mask-1)) {
3919                         const char *first = NULL, *second = NULL;
3920
3921                         /* more than one calling convention set */
3922                         if (declaration->modifiers & DM_CDECL) {
3923                                 if (first == NULL)       first = "cdecl";
3924                                 else if (second == NULL) second = "cdecl";
3925                         }
3926                         if (declaration->modifiers & DM_STDCALL) {
3927                                 if (first == NULL)       first = "stdcall";
3928                                 else if (second == NULL) second = "stdcall";
3929                         }
3930                         if (declaration->modifiers & DM_FASTCALL) {
3931                                 if (first == NULL)       first = "fastcall";
3932                                 else if (second == NULL) second = "fastcall";
3933                         }
3934                         if (declaration->modifiers & DM_THISCALL) {
3935                                 if (first == NULL)       first = "thiscall";
3936                                 else if (second == NULL) second = "thiscall";
3937                         }
3938                         errorf(&declaration->source_position, "%s and %s attributes are not compatible", first, second);
3939                 }
3940
3941                 if (declaration->modifiers & DM_CDECL)
3942                         type->function.calling_convention = CC_CDECL;
3943                 else if (declaration->modifiers & DM_STDCALL)
3944                         type->function.calling_convention = CC_STDCALL;
3945                 else if (declaration->modifiers & DM_FASTCALL)
3946                         type->function.calling_convention = CC_FASTCALL;
3947                 else if (declaration->modifiers & DM_THISCALL)
3948                         type->function.calling_convention = CC_THISCALL;
3949         } else {
3950                 type = allocate_type_zero(TYPE_FUNCTION, HERE);
3951         }
3952
3953         declaration_t *parameters = parse_parameters(&type->function);
3954         if (declaration != NULL) {
3955                 declaration->scope.declarations = parameters;
3956         }
3957
3958         construct_function_type_t *construct_function_type =
3959                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
3960         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
3961         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
3962         construct_function_type->function_type       = type;
3963
3964         return &construct_function_type->construct_type;
3965 }
3966
3967 static void fix_declaration_type(declaration_t *declaration)
3968 {
3969         decl_modifiers_t declaration_modifiers = declaration->modifiers;
3970         type_modifiers_t type_modifiers        = declaration->type->base.modifiers;
3971
3972         if (declaration_modifiers & DM_TRANSPARENT_UNION)
3973                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3974
3975         if (declaration->type->base.modifiers == type_modifiers)
3976                 return;
3977
3978         type_t *copy = duplicate_type(declaration->type);
3979         copy->base.modifiers = type_modifiers;
3980
3981         type_t *result = typehash_insert(copy);
3982         if (result != copy) {
3983                 obstack_free(type_obst, copy);
3984         }
3985
3986         declaration->type = result;
3987 }
3988
3989 static construct_type_t *parse_inner_declarator(declaration_t *declaration,
3990                 bool may_be_abstract)
3991 {
3992         /* construct a single linked list of construct_type_t's which describe
3993          * how to construct the final declarator type */
3994         construct_type_t *first = NULL;
3995         construct_type_t *last  = NULL;
3996         gnu_attribute_t  *attributes = NULL;
3997
3998         decl_modifiers_t modifiers = parse_attributes(&attributes);
3999
4000         /* pointers */
4001         while (token.type == '*') {
4002                 construct_type_t *type = parse_pointer_declarator();
4003
4004                 if (last == NULL) {
4005                         first = type;
4006                         last  = type;
4007                 } else {
4008                         last->next = type;
4009                         last       = type;
4010                 }
4011
4012                 /* TODO: find out if this is correct */
4013                 modifiers |= parse_attributes(&attributes);
4014         }
4015
4016         if (declaration != NULL)
4017                 declaration->modifiers |= modifiers;
4018
4019         construct_type_t *inner_types = NULL;
4020
4021         switch(token.type) {
4022         case T_IDENTIFIER:
4023                 if (declaration == NULL) {
4024                         errorf(HERE, "no identifier expected in typename");
4025                 } else {
4026                         declaration->symbol          = token.v.symbol;
4027                         declaration->source_position = token.source_position;
4028                 }
4029                 next_token();
4030                 break;
4031         case '(':
4032                 next_token();
4033                 add_anchor_token(')');
4034                 inner_types = parse_inner_declarator(declaration, may_be_abstract);
4035                 if (inner_types != NULL) {
4036                         /* All later declarators only modify the return type, not declaration */
4037                         declaration = NULL;
4038                 }
4039                 rem_anchor_token(')');
4040                 expect(')');
4041                 break;
4042         default:
4043                 if (may_be_abstract)
4044                         break;
4045                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
4046                 /* avoid a loop in the outermost scope, because eat_statement doesn't
4047                  * eat '}' */
4048                 if (token.type == '}' && current_function == NULL) {
4049                         next_token();
4050                 } else {
4051                         eat_statement();
4052                 }
4053                 return NULL;
4054         }
4055
4056         construct_type_t *p = last;
4057
4058         while(true) {
4059                 construct_type_t *type;
4060                 switch(token.type) {
4061                 case '(':
4062                         type = parse_function_declarator(declaration);
4063                         break;
4064                 case '[':
4065                         type = parse_array_declarator();
4066                         break;
4067                 default:
4068                         goto declarator_finished;
4069                 }
4070
4071                 /* insert in the middle of the list (behind p) */
4072                 if (p != NULL) {
4073                         type->next = p->next;
4074                         p->next    = type;
4075                 } else {
4076                         type->next = first;
4077                         first      = type;
4078                 }
4079                 if (last == p) {
4080                         last = type;
4081                 }
4082         }
4083
4084 declarator_finished:
4085         /* append inner_types at the end of the list, we don't to set last anymore
4086          * as it's not needed anymore */
4087         if (last == NULL) {
4088                 assert(first == NULL);
4089                 first = inner_types;
4090         } else {
4091                 last->next = inner_types;
4092         }
4093
4094         return first;
4095 end_error:
4096         return NULL;
4097 }
4098
4099 static void parse_declaration_attributes(declaration_t *declaration)
4100 {
4101         gnu_attribute_t  *attributes = NULL;
4102         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
4103
4104         if (declaration == NULL)
4105                 return;
4106
4107         declaration->modifiers |= modifiers;
4108         /* check if we have these stupid mode attributes... */
4109         type_t *old_type = declaration->type;
4110         if (old_type == NULL)
4111                 return;
4112
4113         gnu_attribute_t *attribute = attributes;
4114         for ( ; attribute != NULL; attribute = attribute->next) {
4115                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
4116                         continue;
4117
4118                 atomic_type_kind_t  akind = attribute->u.akind;
4119                 if (!is_type_signed(old_type)) {
4120                         switch(akind) {
4121                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
4122                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
4123                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
4124                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
4125                         default:
4126                                 panic("invalid akind in mode attribute");
4127                         }
4128                 }
4129                 declaration->type
4130                         = make_atomic_type(akind, old_type->base.qualifiers);
4131         }
4132 }
4133
4134 static type_t *construct_declarator_type(construct_type_t *construct_list,
4135                                          type_t *type)
4136 {
4137         construct_type_t *iter = construct_list;
4138         for( ; iter != NULL; iter = iter->next) {
4139                 switch(iter->kind) {
4140                 case CONSTRUCT_INVALID:
4141                         internal_errorf(HERE, "invalid type construction found");
4142                 case CONSTRUCT_FUNCTION: {
4143                         construct_function_type_t *construct_function_type
4144                                 = (construct_function_type_t*) iter;
4145
4146                         type_t *function_type = construct_function_type->function_type;
4147
4148                         function_type->function.return_type = type;
4149
4150                         type_t *skipped_return_type = skip_typeref(type);
4151                         if (is_type_function(skipped_return_type)) {
4152                                 errorf(HERE, "function returning function is not allowed");
4153                                 type = type_error_type;
4154                         } else if (is_type_array(skipped_return_type)) {
4155                                 errorf(HERE, "function returning array is not allowed");
4156                                 type = type_error_type;
4157                         } else {
4158                                 type = function_type;
4159                         }
4160                         break;
4161                 }
4162
4163                 case CONSTRUCT_POINTER: {
4164                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
4165                         type_t           *pointer_type   = allocate_type_zero(TYPE_POINTER, &null_position);
4166                         pointer_type->pointer.points_to  = type;
4167                         pointer_type->base.qualifiers    = parsed_pointer->type_qualifiers;
4168
4169                         type = pointer_type;
4170                         break;
4171                 }
4172
4173                 case CONSTRUCT_ARRAY: {
4174                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
4175                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY, &null_position);
4176
4177                         expression_t *size_expression = parsed_array->size;
4178                         if (size_expression != NULL) {
4179                                 size_expression
4180                                         = create_implicit_cast(size_expression, type_size_t);
4181                         }
4182
4183                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
4184                         array_type->array.element_type    = type;
4185                         array_type->array.is_static       = parsed_array->is_static;
4186                         array_type->array.is_variable     = parsed_array->is_variable;
4187                         array_type->array.size_expression = size_expression;
4188
4189                         if (size_expression != NULL) {
4190                                 if (is_constant_expression(size_expression)) {
4191                                         array_type->array.size_constant = true;
4192                                         array_type->array.size
4193                                                 = fold_constant(size_expression);
4194                                 } else {
4195                                         array_type->array.is_vla = true;
4196                                 }
4197                         }
4198
4199                         type_t *skipped_type = skip_typeref(type);
4200                         if (is_type_atomic(skipped_type, ATOMIC_TYPE_VOID)) {
4201                                 errorf(HERE, "array of void is not allowed");
4202                                 type = type_error_type;
4203                         } else {
4204                                 type = array_type;
4205                         }
4206                         break;
4207                 }
4208                 }
4209
4210                 type_t *hashed_type = typehash_insert(type);
4211                 if (hashed_type != type) {
4212                         /* the function type was constructed earlier freeing it here will
4213                          * destroy other types... */
4214                         if (iter->kind != CONSTRUCT_FUNCTION) {
4215                                 free_type(type);
4216                         }
4217                         type = hashed_type;
4218                 }
4219         }
4220
4221         return type;
4222 }
4223
4224 static declaration_t *parse_declarator(
4225                 const declaration_specifiers_t *specifiers, bool may_be_abstract)
4226 {
4227         declaration_t *const declaration    = allocate_declaration_zero();
4228         declaration->source_position        = specifiers->source_position;
4229         declaration->declared_storage_class = specifiers->declared_storage_class;
4230         declaration->modifiers              = specifiers->modifiers;
4231         declaration->deprecated_string      = specifiers->deprecated_string;
4232         declaration->get_property_sym       = specifiers->get_property_sym;
4233         declaration->put_property_sym       = specifiers->put_property_sym;
4234         declaration->is_inline              = specifiers->is_inline;
4235
4236         declaration->storage_class          = specifiers->declared_storage_class;
4237         if (declaration->storage_class == STORAGE_CLASS_NONE
4238                         && scope != global_scope) {
4239                 declaration->storage_class = STORAGE_CLASS_AUTO;
4240         }
4241
4242         if (specifiers->alignment != 0) {
4243                 /* TODO: add checks here */
4244                 declaration->alignment = specifiers->alignment;
4245         }
4246
4247         construct_type_t *construct_type
4248                 = parse_inner_declarator(declaration, may_be_abstract);
4249         type_t *const type = specifiers->type;
4250         declaration->type = construct_declarator_type(construct_type, type);
4251
4252         parse_declaration_attributes(declaration);
4253
4254         fix_declaration_type(declaration);
4255
4256         if (construct_type != NULL) {
4257                 obstack_free(&temp_obst, construct_type);
4258         }
4259
4260         return declaration;
4261 }
4262
4263 static type_t *parse_abstract_declarator(type_t *base_type)
4264 {
4265         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4266
4267         type_t *result = construct_declarator_type(construct_type, base_type);
4268         if (construct_type != NULL) {
4269                 obstack_free(&temp_obst, construct_type);
4270         }
4271
4272         return result;
4273 }
4274
4275 static declaration_t *append_declaration(declaration_t* const declaration)
4276 {
4277         if (last_declaration != NULL) {
4278                 last_declaration->next = declaration;
4279         } else {
4280                 scope->declarations = declaration;
4281         }
4282         last_declaration = declaration;
4283         return declaration;
4284 }
4285
4286 /**
4287  * Check if the declaration of main is suspicious.  main should be a
4288  * function with external linkage, returning int, taking either zero
4289  * arguments, two, or three arguments of appropriate types, ie.
4290  *
4291  * int main([ int argc, char **argv [, char **env ] ]).
4292  *
4293  * @param decl    the declaration to check
4294  * @param type    the function type of the declaration
4295  */
4296 static void check_type_of_main(const declaration_t *const decl, const function_type_t *const func_type)
4297 {
4298         if (decl->storage_class == STORAGE_CLASS_STATIC) {
4299                 warningf(&decl->source_position,
4300                          "'main' is normally a non-static function");
4301         }
4302         if (skip_typeref(func_type->return_type) != type_int) {
4303                 warningf(&decl->source_position,
4304                          "return type of 'main' should be 'int', but is '%T'",
4305                          func_type->return_type);
4306         }
4307         const function_parameter_t *parm = func_type->parameters;
4308         if (parm != NULL) {
4309                 type_t *const first_type = parm->type;
4310                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4311                         warningf(&decl->source_position,
4312                                  "first argument of 'main' should be 'int', but is '%T'", first_type);
4313                 }
4314                 parm = parm->next;
4315                 if (parm != NULL) {
4316                         type_t *const second_type = parm->type;
4317                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4318                                 warningf(&decl->source_position,
4319                                          "second argument of 'main' should be 'char**', but is '%T'", second_type);
4320                         }
4321                         parm = parm->next;
4322                         if (parm != NULL) {
4323                                 type_t *const third_type = parm->type;
4324                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4325                                         warningf(&decl->source_position,
4326                                                  "third argument of 'main' should be 'char**', but is '%T'", third_type);
4327                                 }
4328                                 parm = parm->next;
4329                                 if (parm != NULL)
4330                                         goto warn_arg_count;
4331                         }
4332                 } else {
4333 warn_arg_count:
4334                         warningf(&decl->source_position, "'main' takes only zero, two or three arguments");
4335                 }
4336         }
4337 }
4338
4339 /**
4340  * Check if a symbol is the equal to "main".
4341  */
4342 static bool is_sym_main(const symbol_t *const sym)
4343 {
4344         return strcmp(sym->string, "main") == 0;
4345 }
4346
4347 static declaration_t *record_declaration(
4348         declaration_t *const declaration,
4349         const bool is_definition)
4350 {
4351         const symbol_t *const symbol  = declaration->symbol;
4352         const namespace_t     namespc = (namespace_t)declaration->namespc;
4353
4354         assert(symbol != NULL);
4355         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4356
4357         type_t *const orig_type = declaration->type;
4358         type_t *const type      = skip_typeref(orig_type);
4359         if (is_type_function(type) &&
4360                         type->function.unspecified_parameters &&
4361                         warning.strict_prototypes &&
4362                         previous_declaration == NULL) {
4363                 warningf(&declaration->source_position,
4364                          "function declaration '%#T' is not a prototype",
4365                          orig_type, declaration->symbol);
4366         }
4367
4368         if (warning.main && is_type_function(type) && is_sym_main(symbol)) {
4369                 check_type_of_main(declaration, &type->function);
4370         }
4371
4372         if (warning.nested_externs                             &&
4373             declaration->storage_class == STORAGE_CLASS_EXTERN &&
4374             scope                      != global_scope) {
4375                 warningf(&declaration->source_position,
4376                          "nested extern declaration of '%#T'", declaration->type, symbol);
4377         }
4378
4379         assert(declaration != previous_declaration);
4380         if (previous_declaration != NULL
4381                         && previous_declaration->parent_scope == scope) {
4382                 /* can happen for K&R style declarations */
4383                 if (previous_declaration->type == NULL) {
4384                         previous_declaration->type = declaration->type;
4385                 }
4386
4387                 const type_t *prev_type = skip_typeref(previous_declaration->type);
4388                 if (!types_compatible(type, prev_type)) {
4389                         errorf(&declaration->source_position,
4390                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
4391                                    orig_type, symbol, previous_declaration->type, symbol,
4392                                    &previous_declaration->source_position);
4393                 } else {
4394                         unsigned old_storage_class = previous_declaration->storage_class;
4395                         if (old_storage_class == STORAGE_CLASS_ENUM_ENTRY) {
4396                                 errorf(&declaration->source_position,
4397                                            "redeclaration of enum entry '%Y' (declared %P)",
4398                                            symbol, &previous_declaration->source_position);
4399                                 return previous_declaration;
4400                         }
4401
4402                         if (warning.redundant_decls                                     &&
4403                             is_definition                                               &&
4404                             previous_declaration->storage_class == STORAGE_CLASS_STATIC &&
4405                             !(previous_declaration->modifiers & DM_USED)                &&
4406                             !previous_declaration->used) {
4407                                 warningf(&previous_declaration->source_position,
4408                                          "unnecessary static forward declaration for '%#T'",
4409                                          previous_declaration->type, symbol);
4410                         }
4411
4412                         unsigned new_storage_class = declaration->storage_class;
4413
4414                         if (is_type_incomplete(prev_type)) {
4415                                 previous_declaration->type = type;
4416                                 prev_type                  = type;
4417                         }
4418
4419                         /* pretend no storage class means extern for function
4420                          * declarations (except if the previous declaration is neither
4421                          * none nor extern) */
4422                         if (is_type_function(type)) {
4423                                 if (prev_type->function.unspecified_parameters) {
4424                                         previous_declaration->type = type;
4425                                         prev_type                  = type;
4426                                 }
4427
4428                                 switch (old_storage_class) {
4429                                 case STORAGE_CLASS_NONE:
4430                                         old_storage_class = STORAGE_CLASS_EXTERN;
4431                                         /* FALLTHROUGH */
4432
4433                                 case STORAGE_CLASS_EXTERN:
4434                                         if (is_definition) {
4435                                                 if (warning.missing_prototypes &&
4436                                                     prev_type->function.unspecified_parameters &&
4437                                                     !is_sym_main(symbol)) {
4438                                                         warningf(&declaration->source_position,
4439                                                                          "no previous prototype for '%#T'",
4440                                                                          orig_type, symbol);
4441                                                 }
4442                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4443                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4444                                         }
4445                                         break;
4446
4447                                 default:
4448                                         break;
4449                                 }
4450                         }
4451
4452                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
4453                                         new_storage_class == STORAGE_CLASS_EXTERN) {
4454 warn_redundant_declaration:
4455                                 if (!is_definition           &&
4456                                     warning.redundant_decls  &&
4457                                     is_type_valid(prev_type) &&
4458                                     strcmp(previous_declaration->source_position.input_name, "<builtin>") != 0) {
4459                                         warningf(&declaration->source_position,
4460                                                  "redundant declaration for '%Y' (declared %P)",
4461                                                  symbol, &previous_declaration->source_position);
4462                                 }
4463                         } else if (current_function == NULL) {
4464                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
4465                                     new_storage_class == STORAGE_CLASS_STATIC) {
4466                                         errorf(&declaration->source_position,
4467                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
4468                                                symbol, &previous_declaration->source_position);
4469                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4470                                         previous_declaration->storage_class          = STORAGE_CLASS_NONE;
4471                                         previous_declaration->declared_storage_class = STORAGE_CLASS_NONE;
4472                                 } else {
4473                                         goto warn_redundant_declaration;
4474                                 }
4475                         } else if (is_type_valid(prev_type)) {
4476                                 if (old_storage_class == new_storage_class) {
4477                                         errorf(&declaration->source_position,
4478                                                "redeclaration of '%Y' (declared %P)",
4479                                                symbol, &previous_declaration->source_position);
4480                                 } else {
4481                                         errorf(&declaration->source_position,
4482                                                "redeclaration of '%Y' with different linkage (declared %P)",
4483                                                symbol, &previous_declaration->source_position);
4484                                 }
4485                         }
4486                 }
4487
4488                 previous_declaration->modifiers |= declaration->modifiers;
4489                 previous_declaration->is_inline |= declaration->is_inline;
4490                 return previous_declaration;
4491         } else if (is_type_function(type)) {
4492                 if (is_definition &&
4493                     declaration->storage_class != STORAGE_CLASS_STATIC) {
4494                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4495                                 warningf(&declaration->source_position,
4496                                          "no previous prototype for '%#T'", orig_type, symbol);
4497                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4498                                 warningf(&declaration->source_position,
4499                                          "no previous declaration for '%#T'", orig_type,
4500                                          symbol);
4501                         }
4502                 }
4503         } else {
4504                 if (warning.missing_declarations &&
4505                     scope == global_scope && (
4506                       declaration->storage_class == STORAGE_CLASS_NONE ||
4507                       declaration->storage_class == STORAGE_CLASS_THREAD
4508                     )) {
4509                         warningf(&declaration->source_position,
4510                                  "no previous declaration for '%#T'", orig_type, symbol);
4511                 }
4512         }
4513
4514         assert(declaration->parent_scope == NULL);
4515         assert(scope != NULL);
4516
4517         declaration->parent_scope = scope;
4518
4519         environment_push(declaration);
4520         return append_declaration(declaration);
4521 }
4522
4523 static void parser_error_multiple_definition(declaration_t *declaration,
4524                 const source_position_t *source_position)
4525 {
4526         errorf(source_position, "multiple definition of symbol '%Y' (declared %P)",
4527                declaration->symbol, &declaration->source_position);
4528 }
4529
4530 static bool is_declaration_specifier(const token_t *token,
4531                                      bool only_specifiers_qualifiers)
4532 {
4533         switch(token->type) {
4534                 TYPE_SPECIFIERS
4535                 TYPE_QUALIFIERS
4536                         return true;
4537                 case T_IDENTIFIER:
4538                         return is_typedef_symbol(token->v.symbol);
4539
4540                 case T___extension__:
4541                 STORAGE_CLASSES
4542                         return !only_specifiers_qualifiers;
4543
4544                 default:
4545                         return false;
4546         }
4547 }
4548
4549 static void parse_init_declarator_rest(declaration_t *declaration)
4550 {
4551         eat('=');
4552
4553         type_t *orig_type = declaration->type;
4554         type_t *type      = skip_typeref(orig_type);
4555
4556         if (declaration->init.initializer != NULL) {
4557                 parser_error_multiple_definition(declaration, HERE);
4558         }
4559
4560         bool must_be_constant = false;
4561         if (declaration->storage_class == STORAGE_CLASS_STATIC
4562                         || declaration->storage_class == STORAGE_CLASS_THREAD_STATIC
4563                         || declaration->parent_scope == global_scope) {
4564                 must_be_constant = true;
4565         }
4566
4567         if (is_type_function(type)) {
4568                 errorf(&declaration->source_position,
4569                        "function '%#T' is initialized like a variable",
4570                        orig_type, declaration->symbol);
4571                 orig_type = type_error_type;
4572         }
4573
4574         parse_initializer_env_t env;
4575         env.type             = orig_type;
4576         env.must_be_constant = must_be_constant;
4577         env.declaration      = current_init_decl = declaration;
4578
4579         initializer_t *initializer = parse_initializer(&env);
4580         current_init_decl = NULL;
4581
4582         if (!is_type_function(type)) {
4583                 /* § 6.7.5 (22)  array initializers for arrays with unknown size determine
4584                  * the array type size */
4585                 declaration->type             = env.type;
4586                 declaration->init.initializer = initializer;
4587         }
4588 }
4589
4590 /* parse rest of a declaration without any declarator */
4591 static void parse_anonymous_declaration_rest(
4592                 const declaration_specifiers_t *specifiers)
4593 {
4594         eat(';');
4595
4596         declaration_t *const declaration    = allocate_declaration_zero();
4597         declaration->type                   = specifiers->type;
4598         declaration->declared_storage_class = specifiers->declared_storage_class;
4599         declaration->source_position        = specifiers->source_position;
4600         declaration->modifiers              = specifiers->modifiers;
4601
4602         if (declaration->declared_storage_class != STORAGE_CLASS_NONE) {
4603                 warningf(&declaration->source_position,
4604                          "useless storage class in empty declaration");
4605         }
4606         declaration->storage_class = STORAGE_CLASS_NONE;
4607
4608         type_t *type = declaration->type;
4609         switch (type->kind) {
4610                 case TYPE_COMPOUND_STRUCT:
4611                 case TYPE_COMPOUND_UNION: {
4612                         if (type->compound.declaration->symbol == NULL) {
4613                                 warningf(&declaration->source_position,
4614                                          "unnamed struct/union that defines no instances");
4615                         }
4616                         break;
4617                 }
4618
4619                 case TYPE_ENUM:
4620                         break;
4621
4622                 default:
4623                         warningf(&declaration->source_position, "empty declaration");
4624                         break;
4625         }
4626
4627         append_declaration(declaration);
4628 }
4629
4630 static void parse_declaration_rest(declaration_t *ndeclaration,
4631                 const declaration_specifiers_t *specifiers,
4632                 parsed_declaration_func finished_declaration)
4633 {
4634         add_anchor_token(';');
4635         add_anchor_token('=');
4636         add_anchor_token(',');
4637         while(true) {
4638                 declaration_t *declaration =
4639                         finished_declaration(ndeclaration, token.type == '=');
4640
4641                 type_t *orig_type = declaration->type;
4642                 type_t *type      = skip_typeref(orig_type);
4643
4644                 if (type->kind != TYPE_FUNCTION &&
4645                     declaration->is_inline &&
4646                     is_type_valid(type)) {
4647                         warningf(&declaration->source_position,
4648                                  "variable '%Y' declared 'inline'\n", declaration->symbol);
4649                 }
4650
4651                 if (token.type == '=') {
4652                         parse_init_declarator_rest(declaration);
4653                 }
4654
4655                 if (token.type != ',')
4656                         break;
4657                 eat(',');
4658
4659                 ndeclaration = parse_declarator(specifiers, /*may_be_abstract=*/false);
4660         }
4661         expect(';');
4662
4663 end_error:
4664         rem_anchor_token(';');
4665         rem_anchor_token('=');
4666         rem_anchor_token(',');
4667 }
4668
4669 static declaration_t *finished_kr_declaration(declaration_t *declaration, bool is_definition)
4670 {
4671         symbol_t *symbol  = declaration->symbol;
4672         if (symbol == NULL) {
4673                 errorf(HERE, "anonymous declaration not valid as function parameter");
4674                 return declaration;
4675         }
4676         namespace_t namespc = (namespace_t) declaration->namespc;
4677         if (namespc != NAMESPACE_NORMAL) {
4678                 return record_declaration(declaration, false);
4679         }
4680
4681         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4682         if (previous_declaration == NULL ||
4683                         previous_declaration->parent_scope != scope) {
4684                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
4685                        symbol);
4686                 return declaration;
4687         }
4688
4689         if (is_definition) {
4690                 errorf(HERE, "parameter %Y is initialised", declaration->symbol);
4691         }
4692
4693         if (previous_declaration->type == NULL) {
4694                 previous_declaration->type          = declaration->type;
4695                 previous_declaration->declared_storage_class = declaration->declared_storage_class;
4696                 previous_declaration->storage_class = declaration->storage_class;
4697                 previous_declaration->parent_scope  = scope;
4698                 return previous_declaration;
4699         } else {
4700                 return record_declaration(declaration, false);
4701         }
4702 }
4703
4704 static void parse_declaration(parsed_declaration_func finished_declaration)
4705 {
4706         declaration_specifiers_t specifiers;
4707         memset(&specifiers, 0, sizeof(specifiers));
4708         parse_declaration_specifiers(&specifiers);
4709
4710         if (token.type == ';') {
4711                 parse_anonymous_declaration_rest(&specifiers);
4712         } else {
4713                 declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
4714                 parse_declaration_rest(declaration, &specifiers, finished_declaration);
4715         }
4716 }
4717
4718 static type_t *get_default_promoted_type(type_t *orig_type)
4719 {
4720         type_t *result = orig_type;
4721
4722         type_t *type = skip_typeref(orig_type);
4723         if (is_type_integer(type)) {
4724                 result = promote_integer(type);
4725         } else if (type == type_float) {
4726                 result = type_double;
4727         }
4728
4729         return result;
4730 }
4731
4732 static void parse_kr_declaration_list(declaration_t *declaration)
4733 {
4734         type_t *type = skip_typeref(declaration->type);
4735         if (!is_type_function(type))
4736                 return;
4737
4738         if (!type->function.kr_style_parameters)
4739                 return;
4740
4741         /* push function parameters */
4742         int       top        = environment_top();
4743         scope_t  *last_scope = scope;
4744         set_scope(&declaration->scope);
4745
4746         declaration_t *parameter = declaration->scope.declarations;
4747         for ( ; parameter != NULL; parameter = parameter->next) {
4748                 assert(parameter->parent_scope == NULL);
4749                 parameter->parent_scope = scope;
4750                 environment_push(parameter);
4751         }
4752
4753         /* parse declaration list */
4754         while (is_declaration_specifier(&token, false)) {
4755                 parse_declaration(finished_kr_declaration);
4756         }
4757
4758         /* pop function parameters */
4759         assert(scope == &declaration->scope);
4760         set_scope(last_scope);
4761         environment_pop_to(top);
4762
4763         /* update function type */
4764         type_t *new_type = duplicate_type(type);
4765
4766         function_parameter_t *parameters     = NULL;
4767         function_parameter_t *last_parameter = NULL;
4768
4769         declaration_t *parameter_declaration = declaration->scope.declarations;
4770         for( ; parameter_declaration != NULL;
4771                         parameter_declaration = parameter_declaration->next) {
4772                 type_t *parameter_type = parameter_declaration->type;
4773                 if (parameter_type == NULL) {
4774                         if (strict_mode) {
4775                                 errorf(HERE, "no type specified for function parameter '%Y'",
4776                                        parameter_declaration->symbol);
4777                         } else {
4778                                 if (warning.implicit_int) {
4779                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
4780                                                 parameter_declaration->symbol);
4781                                 }
4782                                 parameter_type              = type_int;
4783                                 parameter_declaration->type = parameter_type;
4784                         }
4785                 }
4786
4787                 semantic_parameter(parameter_declaration);
4788                 parameter_type = parameter_declaration->type;
4789
4790                 /*
4791                  * we need the default promoted types for the function type
4792                  */
4793                 parameter_type = get_default_promoted_type(parameter_type);
4794
4795                 function_parameter_t *function_parameter
4796                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
4797                 memset(function_parameter, 0, sizeof(function_parameter[0]));
4798
4799                 function_parameter->type = parameter_type;
4800                 if (last_parameter != NULL) {
4801                         last_parameter->next = function_parameter;
4802                 } else {
4803                         parameters = function_parameter;
4804                 }
4805                 last_parameter = function_parameter;
4806         }
4807
4808         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
4809          * prototype */
4810         new_type->function.parameters             = parameters;
4811         new_type->function.unspecified_parameters = true;
4812
4813         type = typehash_insert(new_type);
4814         if (type != new_type) {
4815                 obstack_free(type_obst, new_type);
4816         }
4817
4818         declaration->type = type;
4819 }
4820
4821 static bool first_err = true;
4822
4823 /**
4824  * When called with first_err set, prints the name of the current function,
4825  * else does noting.
4826  */
4827 static void print_in_function(void)
4828 {
4829         if (first_err) {
4830                 first_err = false;
4831                 diagnosticf("%s: In function '%Y':\n",
4832                         current_function->source_position.input_name,
4833                         current_function->symbol);
4834         }
4835 }
4836
4837 /**
4838  * Check if all labels are defined in the current function.
4839  * Check if all labels are used in the current function.
4840  */
4841 static void check_labels(void)
4842 {
4843         for (const goto_statement_t *goto_statement = goto_first;
4844             goto_statement != NULL;
4845             goto_statement = goto_statement->next) {
4846                 /* skip computed gotos */
4847                 if (goto_statement->expression != NULL)
4848                         continue;
4849
4850                 declaration_t *label = goto_statement->label;
4851
4852                 label->used = true;
4853                 if (label->source_position.input_name == NULL) {
4854                         print_in_function();
4855                         errorf(&goto_statement->base.source_position,
4856                                "label '%Y' used but not defined", label->symbol);
4857                  }
4858         }
4859         goto_first = goto_last = NULL;
4860
4861         if (warning.unused_label) {
4862                 for (const label_statement_t *label_statement = label_first;
4863                          label_statement != NULL;
4864                          label_statement = label_statement->next) {
4865                         const declaration_t *label = label_statement->label;
4866
4867                         if (! label->used) {
4868                                 print_in_function();
4869                                 warningf(&label_statement->base.source_position,
4870                                         "label '%Y' defined but not used", label->symbol);
4871                         }
4872                 }
4873         }
4874         label_first = label_last = NULL;
4875 }
4876
4877 /**
4878  * Check declarations of current_function for unused entities.
4879  */
4880 static void check_declarations(void)
4881 {
4882         if (warning.unused_parameter) {
4883                 const scope_t *scope = &current_function->scope;
4884
4885                 if (is_sym_main(current_function->symbol)) {
4886                         /* do not issue unused warnings for main */
4887                         return;
4888                 }
4889                 const declaration_t *parameter = scope->declarations;
4890                 for (; parameter != NULL; parameter = parameter->next) {
4891                         if (! parameter->used) {
4892                                 print_in_function();
4893                                 warningf(&parameter->source_position,
4894                                          "unused parameter '%Y'", parameter->symbol);
4895                         }
4896                 }
4897         }
4898         if (warning.unused_variable) {
4899         }
4900 }
4901
4902 static int determine_truth(expression_t const* const cond)
4903 {
4904         return
4905                 !is_constant_expression(cond) ? 0 :
4906                 fold_constant(cond) != 0      ? 1 :
4907                 -1;
4908 }
4909
4910 static bool noreturn_candidate;
4911
4912 static void check_reachable(statement_t *const stmt)
4913 {
4914         if (stmt->base.reachable)
4915                 return;
4916         if (stmt->kind != STATEMENT_DO_WHILE)
4917                 stmt->base.reachable = true;
4918
4919         statement_t *last = stmt;
4920         statement_t *next;
4921         switch (stmt->kind) {
4922                 case STATEMENT_INVALID:
4923                 case STATEMENT_EMPTY:
4924                 case STATEMENT_DECLARATION:
4925                 case STATEMENT_ASM:
4926                         next = stmt->base.next;
4927                         break;
4928
4929                 case STATEMENT_COMPOUND:
4930                         next = stmt->compound.statements;
4931                         break;
4932
4933                 case STATEMENT_RETURN:
4934                         noreturn_candidate = false;
4935                         return;
4936
4937                 case STATEMENT_IF: {
4938                         if_statement_t const* const ifs = &stmt->ifs;
4939                         int            const        val = determine_truth(ifs->condition);
4940
4941                         if (val >= 0)
4942                                 check_reachable(ifs->true_statement);
4943
4944                         if (val > 0)
4945                                 return;
4946
4947                         if (ifs->false_statement != NULL) {
4948                                 check_reachable(ifs->false_statement);
4949                                 return;
4950                         }
4951
4952                         next = stmt->base.next;
4953                         break;
4954                 }
4955
4956                 case STATEMENT_SWITCH: {
4957                         switch_statement_t const *const switchs = &stmt->switchs;
4958                         expression_t       const *const expr    = switchs->expression;
4959
4960                         if (is_constant_expression(expr)) {
4961                                 long                    const val      = fold_constant(expr);
4962                                 case_label_statement_t *      defaults = NULL;
4963                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4964                                         if (i->expression == NULL) {
4965                                                 defaults = i;
4966                                                 continue;
4967                                         }
4968
4969                                         if (i->first_case <= val && val <= i->last_case) {
4970                                                 check_reachable((statement_t*)i);
4971                                                 return;
4972                                         }
4973                                 }
4974
4975                                 if (defaults != NULL) {
4976                                         check_reachable((statement_t*)defaults);
4977                                         return;
4978                                 }
4979                         } else {
4980                                 bool has_default = false;
4981                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4982                                         if (i->expression == NULL)
4983                                                 has_default = true;
4984
4985                                         check_reachable((statement_t*)i);
4986                                 }
4987
4988                                 if (has_default)
4989                                         return;
4990                         }
4991
4992                         next = stmt->base.next;
4993                         break;
4994                 }
4995
4996                 case STATEMENT_EXPRESSION: {
4997                         /* Check for noreturn function call */
4998                         expression_t const *const expr = stmt->expression.expression;
4999                         if (expr->kind == EXPR_CALL) {
5000                                 expression_t const *const func = expr->call.function;
5001                                 if (func->kind == EXPR_REFERENCE) {
5002                                         declaration_t const *const decl = func->reference.declaration;
5003                                         if (decl != NULL && decl->modifiers & DM_NORETURN) {
5004                                                 return;
5005                                         }
5006                                 }
5007                         }
5008
5009                         next = stmt->base.next;
5010                         break;
5011                 }
5012
5013                 case STATEMENT_CONTINUE: {
5014                         statement_t *parent = stmt;
5015                         for (;;) {
5016                                 parent = parent->base.parent;
5017                                 if (parent == NULL) /* continue not within loop */
5018                                         return;
5019
5020                                 next = parent;
5021                                 switch (parent->kind) {
5022                                         case STATEMENT_WHILE:    goto continue_while;
5023                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5024                                         case STATEMENT_FOR:      goto continue_for;
5025
5026                                         default: break;
5027                                 }
5028                         }
5029                 }
5030
5031                 case STATEMENT_BREAK: {
5032                         statement_t *parent = stmt;
5033                         for (;;) {
5034                                 parent = parent->base.parent;
5035                                 if (parent == NULL) /* break not within loop/switch */
5036                                         return;
5037
5038                                 switch (parent->kind) {
5039                                         case STATEMENT_SWITCH:
5040                                         case STATEMENT_WHILE:
5041                                         case STATEMENT_DO_WHILE:
5042                                         case STATEMENT_FOR:
5043                                                 last = parent;
5044                                                 next = parent->base.next;
5045                                                 goto found_break_parent;
5046
5047                                         default: break;
5048                                 }
5049                         }
5050 found_break_parent:
5051                         break;
5052                 }
5053
5054                 case STATEMENT_GOTO:
5055                         if (stmt->gotos.expression) {
5056                                 statement_t *parent = stmt->base.parent;
5057                                 if (parent == NULL) /* top level goto */
5058                                         return;
5059                                 next = parent;
5060                         } else {
5061                                 next = stmt->gotos.label->init.statement;
5062                                 if (next == NULL) /* missing label */
5063                                         return;
5064                         }
5065                         break;
5066
5067                 case STATEMENT_LABEL:
5068                         next = stmt->label.statement;
5069                         break;
5070
5071                 case STATEMENT_CASE_LABEL:
5072                         next = stmt->case_label.statement;
5073                         break;
5074
5075                 case STATEMENT_WHILE: {
5076                         while_statement_t const *const whiles = &stmt->whiles;
5077                         int                      const val    = determine_truth(whiles->condition);
5078
5079                         if (val >= 0)
5080                                 check_reachable(whiles->body);
5081
5082                         if (val > 0)
5083                                 return;
5084
5085                         next = stmt->base.next;
5086                         break;
5087                 }
5088
5089                 case STATEMENT_DO_WHILE:
5090                         next = stmt->do_while.body;
5091                         break;
5092
5093                 case STATEMENT_FOR: {
5094                         for_statement_t *const fors = &stmt->fors;
5095
5096                         if (fors->condition_reachable)
5097                                 return;
5098                         fors->condition_reachable = true;
5099
5100                         expression_t const *const cond = fors->condition;
5101                         int          const        val  =
5102                                 cond == NULL ? 1 : determine_truth(cond);
5103
5104                         if (val >= 0)
5105                                 check_reachable(fors->body);
5106
5107                         if (val > 0)
5108                                 return;
5109
5110                         next = stmt->base.next;
5111                         break;
5112                 }
5113
5114                 case STATEMENT_MS_TRY: {
5115                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
5116                         check_reachable(ms_try->try_statement);
5117                         next = ms_try->final_statement;
5118                         break;
5119                 }
5120
5121                 case STATEMENT_LEAVE: {
5122                         statement_t *parent = stmt;
5123                         for (;;) {
5124                                 parent = parent->base.parent;
5125                                 if (parent == NULL) /* __leave not within __try */
5126                                         return;
5127
5128                                 if (parent->kind == STATEMENT_MS_TRY) {
5129                                         last = parent;
5130                                         next = parent->ms_try.final_statement;
5131                                         break;
5132                                 }
5133                         }
5134                         break;
5135                 }
5136         }
5137
5138         while (next == NULL) {
5139                 next = last->base.parent;
5140                 if (next == NULL) {
5141                         noreturn_candidate = false;
5142
5143                         type_t *const type = current_function->type;
5144                         assert(is_type_function(type));
5145                         type_t *const ret  = skip_typeref(type->function.return_type);
5146                         if (warning.return_type                    &&
5147                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
5148                             is_type_valid(ret)                     &&
5149                             !is_sym_main(current_function->symbol)) {
5150                                 warningf(&stmt->base.source_position,
5151                                          "control reaches end of non-void function");
5152                         }
5153                         return;
5154                 }
5155
5156                 switch (next->kind) {
5157                         case STATEMENT_INVALID:
5158                         case STATEMENT_EMPTY:
5159                         case STATEMENT_DECLARATION:
5160                         case STATEMENT_EXPRESSION:
5161                         case STATEMENT_ASM:
5162                         case STATEMENT_RETURN:
5163                         case STATEMENT_CONTINUE:
5164                         case STATEMENT_BREAK:
5165                         case STATEMENT_GOTO:
5166                         case STATEMENT_LEAVE:
5167                                 panic("invalid control flow in function");
5168
5169                         case STATEMENT_COMPOUND:
5170                         case STATEMENT_IF:
5171                         case STATEMENT_SWITCH:
5172                         case STATEMENT_LABEL:
5173                         case STATEMENT_CASE_LABEL:
5174                                 last = next;
5175                                 next = next->base.next;
5176                                 break;
5177
5178                         case STATEMENT_WHILE: {
5179 continue_while:
5180                                 if (next->base.reachable)
5181                                         return;
5182                                 next->base.reachable = true;
5183
5184                                 while_statement_t const *const whiles = &next->whiles;
5185                                 int                      const val    = determine_truth(whiles->condition);
5186
5187                                 if (val >= 0)
5188                                         check_reachable(whiles->body);
5189
5190                                 if (val > 0)
5191                                         return;
5192
5193                                 last = next;
5194                                 next = next->base.next;
5195                                 break;
5196                         }
5197
5198                         case STATEMENT_DO_WHILE: {
5199 continue_do_while:
5200                                 if (next->base.reachable)
5201                                         return;
5202                                 next->base.reachable = true;
5203
5204                                 do_while_statement_t const *const dw  = &next->do_while;
5205                                 int                  const        val = determine_truth(dw->condition);
5206
5207                                 if (val >= 0)
5208                                         check_reachable(dw->body);
5209
5210                                 if (val > 0)
5211                                         return;
5212
5213                                 last = next;
5214                                 next = next->base.next;
5215                                 break;
5216                         }
5217
5218                         case STATEMENT_FOR: {
5219 continue_for:;
5220                                 for_statement_t *const fors = &next->fors;
5221
5222                                 fors->step_reachable = true;
5223
5224                                 if (fors->condition_reachable)
5225                                         return;
5226                                 fors->condition_reachable = true;
5227
5228                                 expression_t const *const cond = fors->condition;
5229                                 int          const        val  =
5230                                         cond == NULL ? 1 : determine_truth(cond);
5231
5232                                 if (val >= 0)
5233                                         check_reachable(fors->body);
5234
5235                                 if (val > 0)
5236                                         return;
5237
5238                                 last = next;
5239                                 next = next->base.next;
5240                                 break;
5241                         }
5242
5243                         case STATEMENT_MS_TRY:
5244                                 last = next;
5245                                 next = next->ms_try.final_statement;
5246                                 break;
5247                 }
5248         }
5249
5250         if (next == NULL) {
5251                 next = stmt->base.parent;
5252                 if (next == NULL) {
5253                         warningf(&stmt->base.source_position,
5254                                  "control reaches end of non-void function");
5255                 }
5256         }
5257
5258         check_reachable(next);
5259 }
5260
5261 static void check_unreachable(statement_t const* const stmt)
5262 {
5263         if (!stmt->base.reachable            &&
5264             stmt->kind != STATEMENT_DO_WHILE &&
5265             stmt->kind != STATEMENT_FOR      &&
5266             (stmt->kind != STATEMENT_COMPOUND || stmt->compound.statements == NULL)) {
5267                 warningf(&stmt->base.source_position, "statement is unreachable");
5268         }
5269
5270         switch (stmt->kind) {
5271                 case STATEMENT_INVALID:
5272                 case STATEMENT_EMPTY:
5273                 case STATEMENT_RETURN:
5274                 case STATEMENT_DECLARATION:
5275                 case STATEMENT_EXPRESSION:
5276                 case STATEMENT_CONTINUE:
5277                 case STATEMENT_BREAK:
5278                 case STATEMENT_GOTO:
5279                 case STATEMENT_ASM:
5280                 case STATEMENT_LEAVE:
5281                         break;
5282
5283                 case STATEMENT_COMPOUND:
5284                         if (stmt->compound.statements)
5285                                 check_unreachable(stmt->compound.statements);
5286                         break;
5287
5288                 case STATEMENT_IF:
5289                         check_unreachable(stmt->ifs.true_statement);
5290                         if (stmt->ifs.false_statement != NULL)
5291                                 check_unreachable(stmt->ifs.false_statement);
5292                         break;
5293
5294                 case STATEMENT_SWITCH:
5295                         check_unreachable(stmt->switchs.body);
5296                         break;
5297
5298                 case STATEMENT_LABEL:
5299                         check_unreachable(stmt->label.statement);
5300                         break;
5301
5302                 case STATEMENT_CASE_LABEL:
5303                         check_unreachable(stmt->case_label.statement);
5304                         break;
5305
5306                 case STATEMENT_WHILE:
5307                         check_unreachable(stmt->whiles.body);
5308                         break;
5309
5310                 case STATEMENT_DO_WHILE:
5311                         check_unreachable(stmt->do_while.body);
5312                         if (!stmt->base.reachable) {
5313                                 expression_t const *const cond = stmt->do_while.condition;
5314                                 if (determine_truth(cond) >= 0) {
5315                                         warningf(&cond->base.source_position,
5316                                                  "condition of do-while-loop is unreachable");
5317                                 }
5318                         }
5319                         break;
5320
5321                 case STATEMENT_FOR: {
5322                         for_statement_t const* const fors = &stmt->fors;
5323
5324                         // if init and step are unreachable, cond is unreachable, too
5325                         if (!stmt->base.reachable && !fors->step_reachable) {
5326                                 warningf(&stmt->base.source_position, "statement is unreachable");
5327                         } else {
5328                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
5329                                         warningf(&fors->initialisation->base.source_position,
5330                                                  "initialisation of for-statement is unreachable");
5331                                 }
5332
5333                                 if (!fors->condition_reachable && fors->condition != NULL) {
5334                                         warningf(&fors->condition->base.source_position,
5335                                                  "condition of for-statement is unreachable");
5336                                 }
5337
5338                                 if (!fors->step_reachable && fors->step != NULL) {
5339                                         warningf(&fors->step->base.source_position,
5340                                                  "step of for-statement is unreachable");
5341                                 }
5342                         }
5343
5344                         check_unreachable(fors->body);
5345                         break;
5346                 }
5347
5348                 case STATEMENT_MS_TRY: {
5349                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
5350                         check_unreachable(ms_try->try_statement);
5351                         check_unreachable(ms_try->final_statement);
5352                 }
5353         }
5354
5355         if (stmt->base.next)
5356                 check_unreachable(stmt->base.next);
5357 }
5358
5359 static void parse_external_declaration(void)
5360 {
5361         /* function-definitions and declarations both start with declaration
5362          * specifiers */
5363         declaration_specifiers_t specifiers;
5364         memset(&specifiers, 0, sizeof(specifiers));
5365
5366         add_anchor_token(';');
5367         parse_declaration_specifiers(&specifiers);
5368         rem_anchor_token(';');
5369
5370         /* must be a declaration */
5371         if (token.type == ';') {
5372                 parse_anonymous_declaration_rest(&specifiers);
5373                 return;
5374         }
5375
5376         add_anchor_token(',');
5377         add_anchor_token('=');
5378         rem_anchor_token(';');
5379
5380         /* declarator is common to both function-definitions and declarations */
5381         declaration_t *ndeclaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
5382
5383         rem_anchor_token(',');
5384         rem_anchor_token('=');
5385         rem_anchor_token(';');
5386
5387         /* must be a declaration */
5388         switch (token.type) {
5389                 case ',':
5390                 case ';':
5391                 case '=':
5392                         parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
5393                         return;
5394         }
5395
5396         /* must be a function definition */
5397         parse_kr_declaration_list(ndeclaration);
5398
5399         if (token.type != '{') {
5400                 parse_error_expected("while parsing function definition", '{', NULL);
5401                 eat_until_matching_token(';');
5402                 return;
5403         }
5404
5405         type_t *type = ndeclaration->type;
5406
5407         /* note that we don't skip typerefs: the standard doesn't allow them here
5408          * (so we can't use is_type_function here) */
5409         if (type->kind != TYPE_FUNCTION) {
5410                 if (is_type_valid(type)) {
5411                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5412                                type, ndeclaration->symbol);
5413                 }
5414                 eat_block();
5415                 return;
5416         }
5417
5418         if (warning.aggregate_return &&
5419             is_type_compound(skip_typeref(type->function.return_type))) {
5420                 warningf(HERE, "function '%Y' returns an aggregate",
5421                          ndeclaration->symbol);
5422         }
5423         if (warning.traditional && !type->function.unspecified_parameters) {
5424                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
5425                         ndeclaration->symbol);
5426         }
5427         if (warning.old_style_definition && type->function.unspecified_parameters) {
5428                 warningf(HERE, "old-style function definition '%Y'",
5429                         ndeclaration->symbol);
5430         }
5431
5432         /* § 6.7.5.3 (14) a function definition with () means no
5433          * parameters (and not unspecified parameters) */
5434         if (type->function.unspecified_parameters
5435                         && type->function.parameters == NULL
5436                         && !type->function.kr_style_parameters) {
5437                 type_t *duplicate = duplicate_type(type);
5438                 duplicate->function.unspecified_parameters = false;
5439
5440                 type = typehash_insert(duplicate);
5441                 if (type != duplicate) {
5442                         obstack_free(type_obst, duplicate);
5443                 }
5444                 ndeclaration->type = type;
5445         }
5446
5447         declaration_t *const declaration = record_declaration(ndeclaration, true);
5448         if (ndeclaration != declaration) {
5449                 declaration->scope = ndeclaration->scope;
5450         }
5451         type = skip_typeref(declaration->type);
5452
5453         /* push function parameters and switch scope */
5454         int       top        = environment_top();
5455         scope_t  *last_scope = scope;
5456         set_scope(&declaration->scope);
5457
5458         declaration_t *parameter = declaration->scope.declarations;
5459         for( ; parameter != NULL; parameter = parameter->next) {
5460                 if (parameter->parent_scope == &ndeclaration->scope) {
5461                         parameter->parent_scope = scope;
5462                 }
5463                 assert(parameter->parent_scope == NULL
5464                                 || parameter->parent_scope == scope);
5465                 parameter->parent_scope = scope;
5466                 if (parameter->symbol == NULL) {
5467                         errorf(&parameter->source_position, "parameter name omitted");
5468                         continue;
5469                 }
5470                 environment_push(parameter);
5471         }
5472
5473         if (declaration->init.statement != NULL) {
5474                 parser_error_multiple_definition(declaration, HERE);
5475                 eat_block();
5476         } else {
5477                 /* parse function body */
5478                 int            label_stack_top      = label_top();
5479                 declaration_t *old_current_function = current_function;
5480                 current_function                    = declaration;
5481                 current_parent                      = NULL;
5482
5483                 statement_t *const body = parse_compound_statement(false);
5484                 declaration->init.statement = body;
5485                 first_err = true;
5486                 check_labels();
5487                 check_declarations();
5488                 if (warning.return_type      ||
5489                     warning.unreachable_code ||
5490                     (warning.missing_noreturn && !(declaration->modifiers & DM_NORETURN))) {
5491                         noreturn_candidate = true;
5492                         check_reachable(body);
5493                         if (warning.unreachable_code)
5494                                 check_unreachable(body);
5495                         if (warning.missing_noreturn &&
5496                             noreturn_candidate       &&
5497                             !(declaration->modifiers & DM_NORETURN)) {
5498                                 warningf(&body->base.source_position,
5499                                          "function '%#T' is candidate for attribute 'noreturn'",
5500                                          type, declaration->symbol);
5501                         }
5502                 }
5503
5504                 assert(current_parent   == NULL);
5505                 assert(current_function == declaration);
5506                 current_function = old_current_function;
5507                 label_pop_to(label_stack_top);
5508         }
5509
5510         assert(scope == &declaration->scope);
5511         set_scope(last_scope);
5512         environment_pop_to(top);
5513 }
5514
5515 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5516                                   source_position_t *source_position)
5517 {
5518         type_t *type = allocate_type_zero(TYPE_BITFIELD, source_position);
5519
5520         type->bitfield.base_type = base_type;
5521         type->bitfield.size      = size;
5522
5523         return type;
5524 }
5525
5526 static declaration_t *find_compound_entry(declaration_t *compound_declaration,
5527                                           symbol_t *symbol)
5528 {
5529         declaration_t *iter = compound_declaration->scope.declarations;
5530         for( ; iter != NULL; iter = iter->next) {
5531                 if (iter->namespc != NAMESPACE_NORMAL)
5532                         continue;
5533
5534                 if (iter->symbol == NULL) {
5535                         type_t *type = skip_typeref(iter->type);
5536                         if (is_type_compound(type)) {
5537                                 declaration_t *result
5538                                         = find_compound_entry(type->compound.declaration, symbol);
5539                                 if (result != NULL)
5540                                         return result;
5541                         }
5542                         continue;
5543                 }
5544
5545                 if (iter->symbol == symbol) {
5546                         return iter;
5547                 }
5548         }
5549
5550         return NULL;
5551 }
5552
5553 static void parse_compound_declarators(declaration_t *struct_declaration,
5554                 const declaration_specifiers_t *specifiers)
5555 {
5556         declaration_t *last_declaration = struct_declaration->scope.declarations;
5557         if (last_declaration != NULL) {
5558                 while (last_declaration->next != NULL) {
5559                         last_declaration = last_declaration->next;
5560                 }
5561         }
5562
5563         while (true) {
5564                 declaration_t *declaration;
5565
5566                 if (token.type == ':') {
5567                         source_position_t source_position = *HERE;
5568                         next_token();
5569
5570                         type_t *base_type = specifiers->type;
5571                         expression_t *size = parse_constant_expression();
5572
5573                         if (!is_type_integer(skip_typeref(base_type))) {
5574                                 errorf(HERE, "bitfield base type '%T' is not an integer type",
5575                                        base_type);
5576                         }
5577
5578                         type_t *type = make_bitfield_type(base_type, size, &source_position);
5579
5580                         declaration                         = allocate_declaration_zero();
5581                         declaration->namespc                = NAMESPACE_NORMAL;
5582                         declaration->declared_storage_class = STORAGE_CLASS_NONE;
5583                         declaration->storage_class          = STORAGE_CLASS_NONE;
5584                         declaration->source_position        = source_position;
5585                         declaration->modifiers              = specifiers->modifiers;
5586                         declaration->type                   = type;
5587                 } else {
5588                         declaration = parse_declarator(specifiers,/*may_be_abstract=*/true);
5589
5590                         type_t *orig_type = declaration->type;
5591                         type_t *type      = skip_typeref(orig_type);
5592
5593                         if (token.type == ':') {
5594                                 source_position_t source_position = *HERE;
5595                                 next_token();
5596                                 expression_t *size = parse_constant_expression();
5597
5598                                 if (!is_type_integer(type)) {
5599                                         errorf(HERE, "bitfield base type '%T' is not an integer type",
5600                                                orig_type);
5601                                 }
5602
5603                                 type_t *bitfield_type = make_bitfield_type(orig_type, size, &source_position);
5604                                 declaration->type = bitfield_type;
5605                         } else {
5606                                 /* TODO we ignore arrays for now... what is missing is a check
5607                                  * that they're at the end of the struct */
5608                                 if (is_type_incomplete(type) && !is_type_array(type)) {
5609                                         errorf(HERE,
5610                                                "compound member '%Y' has incomplete type '%T'",
5611                                                declaration->symbol, orig_type);
5612                                 } else if (is_type_function(type)) {
5613                                         errorf(HERE, "compound member '%Y' must not have function type '%T'",
5614                                                declaration->symbol, orig_type);
5615                                 }
5616                         }
5617                 }
5618
5619                 /* make sure we don't define a symbol multiple times */
5620                 symbol_t *symbol = declaration->symbol;
5621                 if (symbol != NULL) {
5622                         declaration_t *prev_decl
5623                                 = find_compound_entry(struct_declaration, symbol);
5624
5625                         if (prev_decl != NULL) {
5626                                 assert(prev_decl->symbol == symbol);
5627                                 errorf(&declaration->source_position,
5628                                        "multiple declarations of symbol '%Y' (declared %P)",
5629                                        symbol, &prev_decl->source_position);
5630                         }
5631                 }
5632
5633                 /* append declaration */
5634                 if (last_declaration != NULL) {
5635                         last_declaration->next = declaration;
5636                 } else {
5637                         struct_declaration->scope.declarations = declaration;
5638                 }
5639                 last_declaration = declaration;
5640
5641                 if (token.type != ',')
5642                         break;
5643                 next_token();
5644         }
5645         expect(';');
5646
5647 end_error:
5648         ;
5649 }
5650
5651 static void parse_compound_type_entries(declaration_t *compound_declaration)
5652 {
5653         eat('{');
5654         add_anchor_token('}');
5655
5656         while (token.type != '}' && token.type != T_EOF) {
5657                 declaration_specifiers_t specifiers;
5658                 memset(&specifiers, 0, sizeof(specifiers));
5659                 parse_declaration_specifiers(&specifiers);
5660
5661                 parse_compound_declarators(compound_declaration, &specifiers);
5662         }
5663         rem_anchor_token('}');
5664
5665         if (token.type == T_EOF) {
5666                 errorf(HERE, "EOF while parsing struct");
5667         }
5668         next_token();
5669 }
5670
5671 static type_t *parse_typename(void)
5672 {
5673         declaration_specifiers_t specifiers;
5674         memset(&specifiers, 0, sizeof(specifiers));
5675         parse_declaration_specifiers(&specifiers);
5676         if (specifiers.declared_storage_class != STORAGE_CLASS_NONE) {
5677                 /* TODO: improve error message, user does probably not know what a
5678                  * storage class is...
5679                  */
5680                 errorf(HERE, "typename may not have a storage class");
5681         }
5682
5683         type_t *result = parse_abstract_declarator(specifiers.type);
5684
5685         return result;
5686 }
5687
5688
5689
5690
5691 typedef expression_t* (*parse_expression_function) (unsigned precedence);
5692 typedef expression_t* (*parse_expression_infix_function) (unsigned precedence,
5693                                                           expression_t *left);
5694
5695 typedef struct expression_parser_function_t expression_parser_function_t;
5696 struct expression_parser_function_t {
5697         unsigned                         precedence;
5698         parse_expression_function        parser;
5699         unsigned                         infix_precedence;
5700         parse_expression_infix_function  infix_parser;
5701 };
5702
5703 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
5704
5705 /**
5706  * Prints an error message if an expression was expected but not read
5707  */
5708 static expression_t *expected_expression_error(void)
5709 {
5710         /* skip the error message if the error token was read */
5711         if (token.type != T_ERROR) {
5712                 errorf(HERE, "expected expression, got token '%K'", &token);
5713         }
5714         next_token();
5715
5716         return create_invalid_expression();
5717 }
5718
5719 /**
5720  * Parse a string constant.
5721  */
5722 static expression_t *parse_string_const(void)
5723 {
5724         wide_string_t wres;
5725         if (token.type == T_STRING_LITERAL) {
5726                 string_t res = token.v.string;
5727                 next_token();
5728                 while (token.type == T_STRING_LITERAL) {
5729                         res = concat_strings(&res, &token.v.string);
5730                         next_token();
5731                 }
5732                 if (token.type != T_WIDE_STRING_LITERAL) {
5733                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
5734                         /* note: that we use type_char_ptr here, which is already the
5735                          * automatic converted type. revert_automatic_type_conversion
5736                          * will construct the array type */
5737                         cnst->base.type    = warning.write_strings ? type_const_char_ptr : type_char_ptr;
5738                         cnst->string.value = res;
5739                         return cnst;
5740                 }
5741
5742                 wres = concat_string_wide_string(&res, &token.v.wide_string);
5743         } else {
5744                 wres = token.v.wide_string;
5745         }
5746         next_token();
5747
5748         for (;;) {
5749                 switch (token.type) {
5750                         case T_WIDE_STRING_LITERAL:
5751                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
5752                                 break;
5753
5754                         case T_STRING_LITERAL:
5755                                 wres = concat_wide_string_string(&wres, &token.v.string);
5756                                 break;
5757
5758                         default: {
5759                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
5760                                 cnst->base.type         = warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
5761                                 cnst->wide_string.value = wres;
5762                                 return cnst;
5763                         }
5764                 }
5765                 next_token();
5766         }
5767 }
5768
5769 /**
5770  * Parse an integer constant.
5771  */
5772 static expression_t *parse_int_const(void)
5773 {
5774         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5775         cnst->base.source_position = *HERE;
5776         cnst->base.type            = token.datatype;
5777         cnst->conste.v.int_value   = token.v.intvalue;
5778
5779         next_token();
5780
5781         return cnst;
5782 }
5783
5784 /**
5785  * Parse a character constant.
5786  */
5787 static expression_t *parse_character_constant(void)
5788 {
5789         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
5790
5791         cnst->base.source_position = *HERE;
5792         cnst->base.type            = token.datatype;
5793         cnst->conste.v.character   = token.v.string;
5794
5795         if (cnst->conste.v.character.size != 1) {
5796                 if (warning.multichar && (c_mode & _GNUC)) {
5797                         /* TODO */
5798                         warningf(HERE, "multi-character character constant");
5799                 } else {
5800                         errorf(HERE, "more than 1 characters in character constant");
5801                 }
5802         }
5803         next_token();
5804
5805         return cnst;
5806 }
5807
5808 /**
5809  * Parse a wide character constant.
5810  */
5811 static expression_t *parse_wide_character_constant(void)
5812 {
5813         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
5814
5815         cnst->base.source_position    = *HERE;
5816         cnst->base.type               = token.datatype;
5817         cnst->conste.v.wide_character = token.v.wide_string;
5818
5819         if (cnst->conste.v.wide_character.size != 1) {
5820                 if (warning.multichar && (c_mode & _GNUC)) {
5821                         /* TODO */
5822                         warningf(HERE, "multi-character character constant");
5823                 } else {
5824                         errorf(HERE, "more than 1 characters in character constant");
5825                 }
5826         }
5827         next_token();
5828
5829         return cnst;
5830 }
5831
5832 /**
5833  * Parse a float constant.
5834  */
5835 static expression_t *parse_float_const(void)
5836 {
5837         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5838         cnst->base.type            = token.datatype;
5839         cnst->conste.v.float_value = token.v.floatvalue;
5840
5841         next_token();
5842
5843         return cnst;
5844 }
5845
5846 static declaration_t *create_implicit_function(symbol_t *symbol,
5847                 const source_position_t *source_position)
5848 {
5849         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION, source_position);
5850         ntype->function.return_type            = type_int;
5851         ntype->function.unspecified_parameters = true;
5852
5853         type_t *type = typehash_insert(ntype);
5854         if (type != ntype) {
5855                 free_type(ntype);
5856         }
5857
5858         declaration_t *const declaration    = allocate_declaration_zero();
5859         declaration->storage_class          = STORAGE_CLASS_EXTERN;
5860         declaration->declared_storage_class = STORAGE_CLASS_EXTERN;
5861         declaration->type                   = type;
5862         declaration->symbol                 = symbol;
5863         declaration->source_position        = *source_position;
5864         declaration->implicit               = true;
5865
5866         bool strict_prototypes_old = warning.strict_prototypes;
5867         warning.strict_prototypes  = false;
5868         record_declaration(declaration, false);
5869         warning.strict_prototypes = strict_prototypes_old;
5870
5871         return declaration;
5872 }
5873
5874 /**
5875  * Creates a return_type (func)(argument_type) function type if not
5876  * already exists.
5877  */
5878 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
5879                                     type_t *argument_type2)
5880 {
5881         function_parameter_t *parameter2
5882                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
5883         memset(parameter2, 0, sizeof(parameter2[0]));
5884         parameter2->type = argument_type2;
5885
5886         function_parameter_t *parameter1
5887                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
5888         memset(parameter1, 0, sizeof(parameter1[0]));
5889         parameter1->type = argument_type1;
5890         parameter1->next = parameter2;
5891
5892         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5893         type->function.return_type = return_type;
5894         type->function.parameters  = parameter1;
5895
5896         type_t *result = typehash_insert(type);
5897         if (result != type) {
5898                 free_type(type);
5899         }
5900
5901         return result;
5902 }
5903
5904 /**
5905  * Creates a return_type (func)(argument_type) function type if not
5906  * already exists.
5907  *
5908  * @param return_type    the return type
5909  * @param argument_type  the argument type
5910  */
5911 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
5912 {
5913         function_parameter_t *parameter
5914                 = obstack_alloc(type_obst, sizeof(parameter[0]));
5915         memset(parameter, 0, sizeof(parameter[0]));
5916         parameter->type = argument_type;
5917
5918         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5919         type->function.return_type = return_type;
5920         type->function.parameters  = parameter;
5921
5922         type_t *result = typehash_insert(type);
5923         if (result != type) {
5924                 free_type(type);
5925         }
5926
5927         return result;
5928 }
5929
5930 static type_t *make_function_0_type(type_t *return_type)
5931 {
5932         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5933         type->function.return_type = return_type;
5934         type->function.parameters  = NULL;
5935
5936         type_t *result = typehash_insert(type);
5937         if (result != type) {
5938                 free_type(type);
5939         }
5940
5941         return result;
5942 }
5943
5944 /**
5945  * Creates a function type for some function like builtins.
5946  *
5947  * @param symbol   the symbol describing the builtin
5948  */
5949 static type_t *get_builtin_symbol_type(symbol_t *symbol)
5950 {
5951         switch(symbol->ID) {
5952         case T___builtin_alloca:
5953                 return make_function_1_type(type_void_ptr, type_size_t);
5954         case T___builtin_huge_val:
5955                 return make_function_0_type(type_double);
5956         case T___builtin_nan:
5957                 return make_function_1_type(type_double, type_char_ptr);
5958         case T___builtin_nanf:
5959                 return make_function_1_type(type_float, type_char_ptr);
5960         case T___builtin_nand:
5961                 return make_function_1_type(type_long_double, type_char_ptr);
5962         case T___builtin_va_end:
5963                 return make_function_1_type(type_void, type_valist);
5964         case T___builtin_expect:
5965                 return make_function_2_type(type_long, type_long, type_long);
5966         default:
5967                 internal_errorf(HERE, "not implemented builtin symbol found");
5968         }
5969 }
5970
5971 /**
5972  * Performs automatic type cast as described in § 6.3.2.1.
5973  *
5974  * @param orig_type  the original type
5975  */
5976 static type_t *automatic_type_conversion(type_t *orig_type)
5977 {
5978         type_t *type = skip_typeref(orig_type);
5979         if (is_type_array(type)) {
5980                 array_type_t *array_type   = &type->array;
5981                 type_t       *element_type = array_type->element_type;
5982                 unsigned      qualifiers   = array_type->base.qualifiers;
5983
5984                 return make_pointer_type(element_type, qualifiers);
5985         }
5986
5987         if (is_type_function(type)) {
5988                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
5989         }
5990
5991         return orig_type;
5992 }
5993
5994 /**
5995  * reverts the automatic casts of array to pointer types and function
5996  * to function-pointer types as defined § 6.3.2.1
5997  */
5998 type_t *revert_automatic_type_conversion(const expression_t *expression)
5999 {
6000         switch (expression->kind) {
6001                 case EXPR_REFERENCE: return expression->reference.declaration->type;
6002
6003                 case EXPR_SELECT:
6004                         return get_qualified_type(expression->select.compound_entry->type,
6005                                                   expression->base.type->base.qualifiers);
6006
6007                 case EXPR_UNARY_DEREFERENCE: {
6008                         const expression_t *const value = expression->unary.value;
6009                         type_t             *const type  = skip_typeref(value->base.type);
6010                         assert(is_type_pointer(type));
6011                         return type->pointer.points_to;
6012                 }
6013
6014                 case EXPR_BUILTIN_SYMBOL:
6015                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
6016
6017                 case EXPR_ARRAY_ACCESS: {
6018                         const expression_t *array_ref = expression->array_access.array_ref;
6019                         type_t             *type_left = skip_typeref(array_ref->base.type);
6020                         if (!is_type_valid(type_left))
6021                                 return type_left;
6022                         assert(is_type_pointer(type_left));
6023                         return type_left->pointer.points_to;
6024                 }
6025
6026                 case EXPR_STRING_LITERAL: {
6027                         size_t size = expression->string.value.size;
6028                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
6029                 }
6030
6031                 case EXPR_WIDE_STRING_LITERAL: {
6032                         size_t size = expression->wide_string.value.size;
6033                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
6034                 }
6035
6036                 case EXPR_COMPOUND_LITERAL:
6037                         return expression->compound_literal.type;
6038
6039                 default: break;
6040         }
6041
6042         return expression->base.type;
6043 }
6044
6045 static expression_t *parse_reference(void)
6046 {
6047         expression_t *expression = allocate_expression_zero(EXPR_REFERENCE);
6048
6049         reference_expression_t *ref = &expression->reference;
6050         symbol_t *const symbol = token.v.symbol;
6051
6052         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
6053
6054         if (declaration == NULL) {
6055                 if (look_ahead(1)->type == '(') {
6056                         /* an implicitly declared function */
6057                         if (strict_mode) {
6058                                 errorf(HERE, "unknown symbol '%Y' found.", symbol);
6059                         } else if (warning.implicit_function_declaration) {
6060                                 warningf(HERE, "implicit declaration of function '%Y'",
6061                                         symbol);
6062                         }
6063
6064                         declaration = create_implicit_function(symbol, HERE);
6065                 } else {
6066                         errorf(HERE, "unknown symbol '%Y' found.", symbol);
6067                         declaration = create_error_declaration(symbol, STORAGE_CLASS_NONE);
6068                 }
6069         }
6070
6071         type_t *type = declaration->type;
6072
6073         /* we always do the auto-type conversions; the & and sizeof parser contains
6074          * code to revert this! */
6075         type = automatic_type_conversion(type);
6076
6077         ref->declaration = declaration;
6078         ref->base.type   = type;
6079
6080         /* this declaration is used */
6081         declaration->used = true;
6082
6083         /* check for deprecated functions */
6084         if (warning.deprecated_declarations &&
6085             declaration->modifiers & DM_DEPRECATED) {
6086                 char const *const prefix = is_type_function(declaration->type) ?
6087                         "function" : "variable";
6088
6089                 if (declaration->deprecated_string != NULL) {
6090                         warningf(HERE, "%s '%Y' is deprecated (declared %P): \"%s\"",
6091                                 prefix, declaration->symbol, &declaration->source_position,
6092                                 declaration->deprecated_string);
6093                 } else {
6094                         warningf(HERE, "%s '%Y' is deprecated (declared %P)", prefix,
6095                                 declaration->symbol, &declaration->source_position);
6096                 }
6097         }
6098         if (warning.init_self && declaration == current_init_decl) {
6099                 current_init_decl = NULL;
6100                 warningf(HERE, "variable '%#T' is initialized by itself",
6101                         declaration->type, declaration->symbol);
6102         }
6103
6104         next_token();
6105         return expression;
6106 }
6107
6108 static bool semantic_cast(expression_t *cast)
6109 {
6110         expression_t            *expression      = cast->unary.value;
6111         type_t                  *orig_dest_type  = cast->base.type;
6112         type_t                  *orig_type_right = expression->base.type;
6113         type_t            const *dst_type        = skip_typeref(orig_dest_type);
6114         type_t            const *src_type        = skip_typeref(orig_type_right);
6115         source_position_t const *pos             = &cast->base.source_position;
6116
6117         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
6118         if (dst_type == type_void)
6119                 return true;
6120
6121         /* only integer and pointer can be casted to pointer */
6122         if (is_type_pointer(dst_type)  &&
6123             !is_type_pointer(src_type) &&
6124             !is_type_integer(src_type) &&
6125             is_type_valid(src_type)) {
6126                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
6127                 return false;
6128         }
6129
6130         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
6131                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
6132                 return false;
6133         }
6134
6135         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
6136                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
6137                 return false;
6138         }
6139
6140         if (warning.cast_qual &&
6141             is_type_pointer(src_type) &&
6142             is_type_pointer(dst_type)) {
6143                 type_t *src = skip_typeref(src_type->pointer.points_to);
6144                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
6145                 unsigned missing_qualifiers =
6146                         src->base.qualifiers & ~dst->base.qualifiers;
6147                 if (missing_qualifiers != 0) {
6148                         warningf(pos,
6149                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
6150                                  missing_qualifiers, orig_type_right);
6151                 }
6152         }
6153         return true;
6154 }
6155
6156 static expression_t *parse_compound_literal(type_t *type)
6157 {
6158         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
6159
6160         parse_initializer_env_t env;
6161         env.type             = type;
6162         env.declaration      = NULL;
6163         env.must_be_constant = false;
6164         initializer_t *initializer = parse_initializer(&env);
6165         type = env.type;
6166
6167         expression->compound_literal.initializer = initializer;
6168         expression->compound_literal.type        = type;
6169         expression->base.type                    = automatic_type_conversion(type);
6170
6171         return expression;
6172 }
6173
6174 /**
6175  * Parse a cast expression.
6176  */
6177 static expression_t *parse_cast(void)
6178 {
6179         source_position_t source_position = token.source_position;
6180
6181         type_t *type  = parse_typename();
6182
6183         /* matching add_anchor_token() is at call site */
6184         rem_anchor_token(')');
6185         expect(')');
6186
6187         if (token.type == '{') {
6188                 return parse_compound_literal(type);
6189         }
6190
6191         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
6192         cast->base.source_position = source_position;
6193
6194         expression_t *value = parse_sub_expression(20);
6195         cast->base.type   = type;
6196         cast->unary.value = value;
6197
6198         if (! semantic_cast(cast)) {
6199                 /* TODO: record the error in the AST. else it is impossible to detect it */
6200         }
6201
6202         return cast;
6203 end_error:
6204         return create_invalid_expression();
6205 }
6206
6207 /**
6208  * Parse a statement expression.
6209  */
6210 static expression_t *parse_statement_expression(void)
6211 {
6212         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
6213
6214         statement_t *statement           = parse_compound_statement(true);
6215         expression->statement.statement  = statement;
6216         expression->base.source_position = statement->base.source_position;
6217
6218         /* find last statement and use its type */
6219         type_t *type = type_void;
6220         const statement_t *stmt = statement->compound.statements;
6221         if (stmt != NULL) {
6222                 while (stmt->base.next != NULL)
6223                         stmt = stmt->base.next;
6224
6225                 if (stmt->kind == STATEMENT_EXPRESSION) {
6226                         type = stmt->expression.expression->base.type;
6227                 }
6228         } else {
6229                 warningf(&expression->base.source_position, "empty statement expression ({})");
6230         }
6231         expression->base.type = type;
6232
6233         expect(')');
6234
6235         return expression;
6236 end_error:
6237         return create_invalid_expression();
6238 }
6239
6240 /**
6241  * Parse a parenthesized expression.
6242  */
6243 static expression_t *parse_parenthesized_expression(void)
6244 {
6245         eat('(');
6246         add_anchor_token(')');
6247
6248         switch(token.type) {
6249         case '{':
6250                 /* gcc extension: a statement expression */
6251                 return parse_statement_expression();
6252
6253         TYPE_QUALIFIERS
6254         TYPE_SPECIFIERS
6255                 return parse_cast();
6256         case T_IDENTIFIER:
6257                 if (is_typedef_symbol(token.v.symbol)) {
6258                         return parse_cast();
6259                 }
6260         }
6261
6262         expression_t *result = parse_expression();
6263         rem_anchor_token(')');
6264         expect(')');
6265
6266         return result;
6267 end_error:
6268         return create_invalid_expression();
6269 }
6270
6271 static expression_t *parse_function_keyword(void)
6272 {
6273         next_token();
6274         /* TODO */
6275
6276         if (current_function == NULL) {
6277                 errorf(HERE, "'__func__' used outside of a function");
6278         }
6279
6280         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6281         expression->base.type     = type_char_ptr;
6282         expression->funcname.kind = FUNCNAME_FUNCTION;
6283
6284         return expression;
6285 }
6286
6287 static expression_t *parse_pretty_function_keyword(void)
6288 {
6289         eat(T___PRETTY_FUNCTION__);
6290
6291         if (current_function == NULL) {
6292                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
6293         }
6294
6295         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6296         expression->base.type     = type_char_ptr;
6297         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
6298
6299         return expression;
6300 }
6301
6302 static expression_t *parse_funcsig_keyword(void)
6303 {
6304         eat(T___FUNCSIG__);
6305
6306         if (current_function == NULL) {
6307                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
6308         }
6309
6310         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6311         expression->base.type     = type_char_ptr;
6312         expression->funcname.kind = FUNCNAME_FUNCSIG;
6313
6314         return expression;
6315 }
6316
6317 static expression_t *parse_funcdname_keyword(void)
6318 {
6319         eat(T___FUNCDNAME__);
6320
6321         if (current_function == NULL) {
6322                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
6323         }
6324
6325         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6326         expression->base.type     = type_char_ptr;
6327         expression->funcname.kind = FUNCNAME_FUNCDNAME;
6328
6329         return expression;
6330 }
6331
6332 static designator_t *parse_designator(void)
6333 {
6334         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
6335         result->source_position = *HERE;
6336
6337         if (token.type != T_IDENTIFIER) {
6338                 parse_error_expected("while parsing member designator",
6339                                      T_IDENTIFIER, NULL);
6340                 return NULL;
6341         }
6342         result->symbol = token.v.symbol;
6343         next_token();
6344
6345         designator_t *last_designator = result;
6346         while(true) {
6347                 if (token.type == '.') {
6348                         next_token();
6349                         if (token.type != T_IDENTIFIER) {
6350                                 parse_error_expected("while parsing member designator",
6351                                                      T_IDENTIFIER, NULL);
6352                                 return NULL;
6353                         }
6354                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6355                         designator->source_position = *HERE;
6356                         designator->symbol          = token.v.symbol;
6357                         next_token();
6358
6359                         last_designator->next = designator;
6360                         last_designator       = designator;
6361                         continue;
6362                 }
6363                 if (token.type == '[') {
6364                         next_token();
6365                         add_anchor_token(']');
6366                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6367                         designator->source_position = *HERE;
6368                         designator->array_index     = parse_expression();
6369                         rem_anchor_token(']');
6370                         expect(']');
6371                         if (designator->array_index == NULL) {
6372                                 return NULL;
6373                         }
6374
6375                         last_designator->next = designator;
6376                         last_designator       = designator;
6377                         continue;
6378                 }
6379                 break;
6380         }
6381
6382         return result;
6383 end_error:
6384         return NULL;
6385 }
6386
6387 /**
6388  * Parse the __builtin_offsetof() expression.
6389  */
6390 static expression_t *parse_offsetof(void)
6391 {
6392         eat(T___builtin_offsetof);
6393
6394         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6395         expression->base.type    = type_size_t;
6396
6397         expect('(');
6398         add_anchor_token(',');
6399         type_t *type = parse_typename();
6400         rem_anchor_token(',');
6401         expect(',');
6402         add_anchor_token(')');
6403         designator_t *designator = parse_designator();
6404         rem_anchor_token(')');
6405         expect(')');
6406
6407         expression->offsetofe.type       = type;
6408         expression->offsetofe.designator = designator;
6409
6410         type_path_t path;
6411         memset(&path, 0, sizeof(path));
6412         path.top_type = type;
6413         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6414
6415         descend_into_subtype(&path);
6416
6417         if (!walk_designator(&path, designator, true)) {
6418                 return create_invalid_expression();
6419         }
6420
6421         DEL_ARR_F(path.path);
6422
6423         return expression;
6424 end_error:
6425         return create_invalid_expression();
6426 }
6427
6428 /**
6429  * Parses a _builtin_va_start() expression.
6430  */
6431 static expression_t *parse_va_start(void)
6432 {
6433         eat(T___builtin_va_start);
6434
6435         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6436
6437         expect('(');
6438         add_anchor_token(',');
6439         expression->va_starte.ap = parse_assignment_expression();
6440         rem_anchor_token(',');
6441         expect(',');
6442         expression_t *const expr = parse_assignment_expression();
6443         if (expr->kind == EXPR_REFERENCE) {
6444                 declaration_t *const decl = expr->reference.declaration;
6445                 if (decl == NULL)
6446                         return create_invalid_expression();
6447                 if (decl->parent_scope == &current_function->scope &&
6448                     decl->next == NULL) {
6449                         expression->va_starte.parameter = decl;
6450                         expect(')');
6451                         return expression;
6452                 }
6453         }
6454         errorf(&expr->base.source_position,
6455                "second argument of 'va_start' must be last parameter of the current function");
6456 end_error:
6457         return create_invalid_expression();
6458 }
6459
6460 /**
6461  * Parses a _builtin_va_arg() expression.
6462  */
6463 static expression_t *parse_va_arg(void)
6464 {
6465         eat(T___builtin_va_arg);
6466
6467         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6468
6469         expect('(');
6470         expression->va_arge.ap = parse_assignment_expression();
6471         expect(',');
6472         expression->base.type = parse_typename();
6473         expect(')');
6474
6475         return expression;
6476 end_error:
6477         return create_invalid_expression();
6478 }
6479
6480 static expression_t *parse_builtin_symbol(void)
6481 {
6482         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
6483
6484         symbol_t *symbol = token.v.symbol;
6485
6486         expression->builtin_symbol.symbol = symbol;
6487         next_token();
6488
6489         type_t *type = get_builtin_symbol_type(symbol);
6490         type = automatic_type_conversion(type);
6491
6492         expression->base.type = type;
6493         return expression;
6494 }
6495
6496 /**
6497  * Parses a __builtin_constant() expression.
6498  */
6499 static expression_t *parse_builtin_constant(void)
6500 {
6501         eat(T___builtin_constant_p);
6502
6503         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6504
6505         expect('(');
6506         add_anchor_token(')');
6507         expression->builtin_constant.value = parse_assignment_expression();
6508         rem_anchor_token(')');
6509         expect(')');
6510         expression->base.type = type_int;
6511
6512         return expression;
6513 end_error:
6514         return create_invalid_expression();
6515 }
6516
6517 /**
6518  * Parses a __builtin_prefetch() expression.
6519  */
6520 static expression_t *parse_builtin_prefetch(void)
6521 {
6522         eat(T___builtin_prefetch);
6523
6524         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
6525
6526         expect('(');
6527         add_anchor_token(')');
6528         expression->builtin_prefetch.adr = parse_assignment_expression();
6529         if (token.type == ',') {
6530                 next_token();
6531                 expression->builtin_prefetch.rw = parse_assignment_expression();
6532         }
6533         if (token.type == ',') {
6534                 next_token();
6535                 expression->builtin_prefetch.locality = parse_assignment_expression();
6536         }
6537         rem_anchor_token(')');
6538         expect(')');
6539         expression->base.type = type_void;
6540
6541         return expression;
6542 end_error:
6543         return create_invalid_expression();
6544 }
6545
6546 /**
6547  * Parses a __builtin_is_*() compare expression.
6548  */
6549 static expression_t *parse_compare_builtin(void)
6550 {
6551         expression_t *expression;
6552
6553         switch(token.type) {
6554         case T___builtin_isgreater:
6555                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6556                 break;
6557         case T___builtin_isgreaterequal:
6558                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6559                 break;
6560         case T___builtin_isless:
6561                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6562                 break;
6563         case T___builtin_islessequal:
6564                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6565                 break;
6566         case T___builtin_islessgreater:
6567                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6568                 break;
6569         case T___builtin_isunordered:
6570                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6571                 break;
6572         default:
6573                 internal_errorf(HERE, "invalid compare builtin found");
6574                 break;
6575         }
6576         expression->base.source_position = *HERE;
6577         next_token();
6578
6579         expect('(');
6580         expression->binary.left = parse_assignment_expression();
6581         expect(',');
6582         expression->binary.right = parse_assignment_expression();
6583         expect(')');
6584
6585         type_t *const orig_type_left  = expression->binary.left->base.type;
6586         type_t *const orig_type_right = expression->binary.right->base.type;
6587
6588         type_t *const type_left  = skip_typeref(orig_type_left);
6589         type_t *const type_right = skip_typeref(orig_type_right);
6590         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6591                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6592                         type_error_incompatible("invalid operands in comparison",
6593                                 &expression->base.source_position, orig_type_left, orig_type_right);
6594                 }
6595         } else {
6596                 semantic_comparison(&expression->binary);
6597         }
6598
6599         return expression;
6600 end_error:
6601         return create_invalid_expression();
6602 }
6603
6604 #if 0
6605 /**
6606  * Parses a __builtin_expect() expression.
6607  */
6608 static expression_t *parse_builtin_expect(void)
6609 {
6610         eat(T___builtin_expect);
6611
6612         expression_t *expression
6613                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
6614
6615         expect('(');
6616         expression->binary.left = parse_assignment_expression();
6617         expect(',');
6618         expression->binary.right = parse_constant_expression();
6619         expect(')');
6620
6621         expression->base.type = expression->binary.left->base.type;
6622
6623         return expression;
6624 end_error:
6625         return create_invalid_expression();
6626 }
6627 #endif
6628
6629 /**
6630  * Parses a MS assume() expression.
6631  */
6632 static expression_t *parse_assume(void)
6633 {
6634         eat(T__assume);
6635
6636         expression_t *expression
6637                 = allocate_expression_zero(EXPR_UNARY_ASSUME);
6638
6639         expect('(');
6640         add_anchor_token(')');
6641         expression->unary.value = parse_assignment_expression();
6642         rem_anchor_token(')');
6643         expect(')');
6644
6645         expression->base.type = type_void;
6646         return expression;
6647 end_error:
6648         return create_invalid_expression();
6649 }
6650
6651 /**
6652  * Return the declaration for a given label symbol or create a new one.
6653  *
6654  * @param symbol  the symbol of the label
6655  */
6656 static declaration_t *get_label(symbol_t *symbol)
6657 {
6658         declaration_t *candidate;
6659         assert(current_function != NULL);
6660
6661         candidate = get_declaration(symbol, NAMESPACE_LOCAL_LABEL);
6662         /* if we found a local label, we already created the declaration */
6663         if (candidate != NULL) {
6664                 assert(candidate->parent_scope == scope);
6665                 return candidate;
6666         }
6667
6668         candidate = get_declaration(symbol, NAMESPACE_LABEL);
6669         /* if we found a label in the same function, then we already created the
6670          * declaration */
6671         if (candidate != NULL
6672                         && candidate->parent_scope == &current_function->scope) {
6673                 return candidate;
6674         }
6675
6676         /* otherwise we need to create a new one */
6677         declaration_t *const declaration = allocate_declaration_zero();
6678         declaration->namespc       = NAMESPACE_LABEL;
6679         declaration->symbol        = symbol;
6680
6681         label_push(declaration);
6682
6683         return declaration;
6684 }
6685
6686 /**
6687  * Parses a GNU && label address expression.
6688  */
6689 static expression_t *parse_label_address(void)
6690 {
6691         source_position_t source_position = token.source_position;
6692         eat(T_ANDAND);
6693         if (token.type != T_IDENTIFIER) {
6694                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
6695                 goto end_error;
6696         }
6697         symbol_t *symbol = token.v.symbol;
6698         next_token();
6699
6700         declaration_t *label = get_label(symbol);
6701
6702         label->used          = true;
6703         label->address_taken = true;
6704
6705         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
6706         expression->base.source_position = source_position;
6707
6708         /* label address is threaten as a void pointer */
6709         expression->base.type                 = type_void_ptr;
6710         expression->label_address.declaration = label;
6711         return expression;
6712 end_error:
6713         return create_invalid_expression();
6714 }
6715
6716 /**
6717  * Parse a microsoft __noop expression.
6718  */
6719 static expression_t *parse_noop_expression(void)
6720 {
6721         source_position_t source_position = *HERE;
6722         eat(T___noop);
6723
6724         if (token.type == '(') {
6725                 /* parse arguments */
6726                 eat('(');
6727                 add_anchor_token(')');
6728                 add_anchor_token(',');
6729
6730                 if (token.type != ')') {
6731                         while(true) {
6732                                 (void)parse_assignment_expression();
6733                                 if (token.type != ',')
6734                                         break;
6735                                 next_token();
6736                         }
6737                 }
6738         }
6739         rem_anchor_token(',');
6740         rem_anchor_token(')');
6741         expect(')');
6742
6743         /* the result is a (int)0 */
6744         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6745         cnst->base.source_position = source_position;
6746         cnst->base.type            = type_int;
6747         cnst->conste.v.int_value   = 0;
6748         cnst->conste.is_ms_noop    = true;
6749
6750         return cnst;
6751
6752 end_error:
6753         return create_invalid_expression();
6754 }
6755
6756 /**
6757  * Parses a primary expression.
6758  */
6759 static expression_t *parse_primary_expression(void)
6760 {
6761         switch (token.type) {
6762                 case T_INTEGER:                  return parse_int_const();
6763                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
6764                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
6765                 case T_FLOATINGPOINT:            return parse_float_const();
6766                 case T_STRING_LITERAL:
6767                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
6768                 case T_IDENTIFIER:               return parse_reference();
6769                 case T___FUNCTION__:
6770                 case T___func__:                 return parse_function_keyword();
6771                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
6772                 case T___FUNCSIG__:              return parse_funcsig_keyword();
6773                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
6774                 case T___builtin_offsetof:       return parse_offsetof();
6775                 case T___builtin_va_start:       return parse_va_start();
6776                 case T___builtin_va_arg:         return parse_va_arg();
6777                 case T___builtin_expect:
6778                 case T___builtin_alloca:
6779                 case T___builtin_nan:
6780                 case T___builtin_nand:
6781                 case T___builtin_nanf:
6782                 case T___builtin_huge_val:
6783                 case T___builtin_va_end:         return parse_builtin_symbol();
6784                 case T___builtin_isgreater:
6785                 case T___builtin_isgreaterequal:
6786                 case T___builtin_isless:
6787                 case T___builtin_islessequal:
6788                 case T___builtin_islessgreater:
6789                 case T___builtin_isunordered:    return parse_compare_builtin();
6790                 case T___builtin_constant_p:     return parse_builtin_constant();
6791                 case T___builtin_prefetch:       return parse_builtin_prefetch();
6792                 case T__assume:                  return parse_assume();
6793                 case T_ANDAND:
6794                         if (c_mode & _GNUC)
6795                                 return parse_label_address();
6796                         break;
6797
6798                 case '(':                        return parse_parenthesized_expression();
6799                 case T___noop:                   return parse_noop_expression();
6800         }
6801
6802         errorf(HERE, "unexpected token %K, expected an expression", &token);
6803         return create_invalid_expression();
6804 }
6805
6806 /**
6807  * Check if the expression has the character type and issue a warning then.
6808  */
6809 static void check_for_char_index_type(const expression_t *expression)
6810 {
6811         type_t       *const type      = expression->base.type;
6812         const type_t *const base_type = skip_typeref(type);
6813
6814         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
6815                         warning.char_subscripts) {
6816                 warningf(&expression->base.source_position,
6817                          "array subscript has type '%T'", type);
6818         }
6819 }
6820
6821 static expression_t *parse_array_expression(unsigned precedence,
6822                                             expression_t *left)
6823 {
6824         (void) precedence;
6825
6826         eat('[');
6827         add_anchor_token(']');
6828
6829         expression_t *inside = parse_expression();
6830
6831         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
6832
6833         array_access_expression_t *array_access = &expression->array_access;
6834
6835         type_t *const orig_type_left   = left->base.type;
6836         type_t *const orig_type_inside = inside->base.type;
6837
6838         type_t *const type_left   = skip_typeref(orig_type_left);
6839         type_t *const type_inside = skip_typeref(orig_type_inside);
6840
6841         type_t *return_type;
6842         if (is_type_pointer(type_left)) {
6843                 return_type             = type_left->pointer.points_to;
6844                 array_access->array_ref = left;
6845                 array_access->index     = inside;
6846                 check_for_char_index_type(inside);
6847         } else if (is_type_pointer(type_inside)) {
6848                 return_type             = type_inside->pointer.points_to;
6849                 array_access->array_ref = inside;
6850                 array_access->index     = left;
6851                 array_access->flipped   = true;
6852                 check_for_char_index_type(left);
6853         } else {
6854                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
6855                         errorf(HERE,
6856                                 "array access on object with non-pointer types '%T', '%T'",
6857                                 orig_type_left, orig_type_inside);
6858                 }
6859                 return_type             = type_error_type;
6860                 array_access->array_ref = create_invalid_expression();
6861         }
6862
6863         rem_anchor_token(']');
6864         if (token.type != ']') {
6865                 parse_error_expected("Problem while parsing array access", ']', NULL);
6866                 return expression;
6867         }
6868         next_token();
6869
6870         return_type           = automatic_type_conversion(return_type);
6871         expression->base.type = return_type;
6872
6873         return expression;
6874 }
6875
6876 static expression_t *parse_typeprop(expression_kind_t const kind,
6877                                     source_position_t const pos,
6878                                     unsigned const precedence)
6879 {
6880         expression_t *tp_expression = allocate_expression_zero(kind);
6881         tp_expression->base.type            = type_size_t;
6882         tp_expression->base.source_position = pos;
6883
6884         char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
6885
6886         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
6887                 next_token();
6888                 add_anchor_token(')');
6889                 type_t* const orig_type = parse_typename();
6890                 tp_expression->typeprop.type = orig_type;
6891
6892                 type_t const* const type = skip_typeref(orig_type);
6893                 char const* const wrong_type =
6894                         is_type_incomplete(type)    ? "incomplete"          :
6895                         type->kind == TYPE_FUNCTION ? "function designator" :
6896                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6897                         NULL;
6898                 if (wrong_type != NULL) {
6899                         errorf(&pos, "operand of %s expression must not be %s type '%T'",
6900                                what, wrong_type, type);
6901                 }
6902
6903                 rem_anchor_token(')');
6904                 expect(')');
6905         } else {
6906                 expression_t *expression = parse_sub_expression(precedence);
6907
6908                 type_t* const orig_type = revert_automatic_type_conversion(expression);
6909                 expression->base.type = orig_type;
6910
6911                 type_t const* const type = skip_typeref(orig_type);
6912                 char const* const wrong_type =
6913                         is_type_incomplete(type)    ? "incomplete"          :
6914                         type->kind == TYPE_FUNCTION ? "function designator" :
6915                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6916                         NULL;
6917                 if (wrong_type != NULL) {
6918                         errorf(&pos, "operand of %s expression must not be expression of %s type '%T'", what, wrong_type, type);
6919                 }
6920
6921                 tp_expression->typeprop.type          = expression->base.type;
6922                 tp_expression->typeprop.tp_expression = expression;
6923         }
6924
6925         return tp_expression;
6926 end_error:
6927         return create_invalid_expression();
6928 }
6929
6930 static expression_t *parse_sizeof(unsigned precedence)
6931 {
6932         source_position_t pos = *HERE;
6933         eat(T_sizeof);
6934         return parse_typeprop(EXPR_SIZEOF, pos, precedence);
6935 }
6936
6937 static expression_t *parse_alignof(unsigned precedence)
6938 {
6939         source_position_t pos = *HERE;
6940         eat(T___alignof__);
6941         return parse_typeprop(EXPR_ALIGNOF, pos, precedence);
6942 }
6943
6944 static expression_t *parse_select_expression(unsigned precedence,
6945                                              expression_t *compound)
6946 {
6947         (void) precedence;
6948         assert(token.type == '.' || token.type == T_MINUSGREATER);
6949
6950         bool is_pointer = (token.type == T_MINUSGREATER);
6951         next_token();
6952
6953         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
6954         select->select.compound = compound;
6955
6956         if (token.type != T_IDENTIFIER) {
6957                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
6958                 return select;
6959         }
6960         symbol_t *symbol = token.v.symbol;
6961         next_token();
6962
6963         type_t *const orig_type = compound->base.type;
6964         type_t *const type      = skip_typeref(orig_type);
6965
6966         type_t *type_left;
6967         bool    saw_error = false;
6968         if (is_type_pointer(type)) {
6969                 if (!is_pointer) {
6970                         errorf(HERE,
6971                                "request for member '%Y' in something not a struct or union, but '%T'",
6972                                symbol, orig_type);
6973                         saw_error = true;
6974                 }
6975                 type_left = skip_typeref(type->pointer.points_to);
6976         } else {
6977                 if (is_pointer && is_type_valid(type)) {
6978                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
6979                         saw_error = true;
6980                 }
6981                 type_left = type;
6982         }
6983
6984         declaration_t *entry;
6985         if (type_left->kind == TYPE_COMPOUND_STRUCT ||
6986             type_left->kind == TYPE_COMPOUND_UNION) {
6987                 declaration_t *const declaration = type_left->compound.declaration;
6988
6989                 if (!declaration->init.complete) {
6990                         errorf(HERE, "request for member '%Y' of incomplete type '%T'",
6991                                symbol, type_left);
6992                         goto create_error_entry;
6993                 }
6994
6995                 entry = find_compound_entry(declaration, symbol);
6996                 if (entry == NULL) {
6997                         errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
6998                         goto create_error_entry;
6999                 }
7000         } else {
7001                 if (is_type_valid(type_left) && !saw_error) {
7002                         errorf(HERE,
7003                                "request for member '%Y' in something not a struct or union, but '%T'",
7004                                symbol, type_left);
7005                 }
7006 create_error_entry:
7007                 entry         = allocate_declaration_zero();
7008                 entry->symbol = symbol;
7009         }
7010
7011         select->select.compound_entry = entry;
7012
7013         type_t *const res_type =
7014                 get_qualified_type(entry->type, type_left->base.qualifiers);
7015
7016         /* we always do the auto-type conversions; the & and sizeof parser contains
7017          * code to revert this! */
7018         select->base.type = automatic_type_conversion(res_type);
7019
7020         type_t *skipped = skip_typeref(res_type);
7021         if (skipped->kind == TYPE_BITFIELD) {
7022                 select->base.type = skipped->bitfield.base_type;
7023         }
7024
7025         return select;
7026 }
7027
7028 static void check_call_argument(const function_parameter_t *parameter,
7029                                 call_argument_t *argument, unsigned pos)
7030 {
7031         type_t         *expected_type      = parameter->type;
7032         type_t         *expected_type_skip = skip_typeref(expected_type);
7033         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
7034         expression_t   *arg_expr           = argument->expression;
7035         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
7036
7037         /* handle transparent union gnu extension */
7038         if (is_type_union(expected_type_skip)
7039                         && (expected_type_skip->base.modifiers
7040                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
7041                 declaration_t  *union_decl = expected_type_skip->compound.declaration;
7042
7043                 declaration_t *declaration = union_decl->scope.declarations;
7044                 type_t        *best_type   = NULL;
7045                 for ( ; declaration != NULL; declaration = declaration->next) {
7046                         type_t *decl_type = declaration->type;
7047                         error = semantic_assign(decl_type, arg_expr);
7048                         if (error == ASSIGN_ERROR_INCOMPATIBLE
7049                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
7050                                 continue;
7051
7052                         if (error == ASSIGN_SUCCESS) {
7053                                 best_type = decl_type;
7054                         } else if (best_type == NULL) {
7055                                 best_type = decl_type;
7056                         }
7057                 }
7058
7059                 if (best_type != NULL) {
7060                         expected_type = best_type;
7061                 }
7062         }
7063
7064         error                = semantic_assign(expected_type, arg_expr);
7065         argument->expression = create_implicit_cast(argument->expression,
7066                                                     expected_type);
7067
7068         if (error != ASSIGN_SUCCESS) {
7069                 /* report exact scope in error messages (like "in argument 3") */
7070                 char buf[64];
7071                 snprintf(buf, sizeof(buf), "call argument %u", pos);
7072                 report_assign_error(error, expected_type, arg_expr,     buf,
7073                                                         &arg_expr->base.source_position);
7074         } else if (warning.traditional | warning.conversion) {
7075                 if (
7076                     /* passing as integer instead of float or complex */
7077                     (is_type_integer(expected_type) &&
7078                      (is_type_float(arg_type) || is_type_complex(arg_type))) ||
7079                     /* passing as complex instead of integer or float */
7080                     (is_type_complex(expected_type) &&
7081                      (is_type_integer(arg_type) || is_type_float(arg_type))) ||
7082                     /* passing as float instead of integer or complex */
7083                     (is_type_float(expected_type) &&
7084                      (is_type_integer(arg_type) || is_type_complex(arg_type))) ||
7085                     /* passing as float instead of double */
7086                     (is_type_float(expected_type) && expected_type != type_double &&
7087                      is_type_float(arg_type))) {
7088                         warningf(&arg_expr->base.source_position,
7089                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
7090                                 pos, expected_type, arg_type);
7091                 }
7092                 if (is_type_integer(expected_type) && is_type_integer(arg_type)) {
7093                         /* TODO check for size HERE */
7094                 }
7095         }
7096 }
7097
7098 /**
7099  * Parse a call expression, ie. expression '( ... )'.
7100  *
7101  * @param expression  the function address
7102  */
7103 static expression_t *parse_call_expression(unsigned precedence,
7104                                            expression_t *expression)
7105 {
7106         (void) precedence;
7107         expression_t *result = allocate_expression_zero(EXPR_CALL);
7108         result->base.source_position = expression->base.source_position;
7109
7110         call_expression_t *call = &result->call;
7111         call->function          = expression;
7112
7113         type_t *const orig_type = expression->base.type;
7114         type_t *const type      = skip_typeref(orig_type);
7115
7116         function_type_t *function_type = NULL;
7117         if (is_type_pointer(type)) {
7118                 type_t *const to_type = skip_typeref(type->pointer.points_to);
7119
7120                 if (is_type_function(to_type)) {
7121                         function_type   = &to_type->function;
7122                         call->base.type = function_type->return_type;
7123                 }
7124         }
7125
7126         if (function_type == NULL && is_type_valid(type)) {
7127                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
7128         }
7129
7130         /* parse arguments */
7131         eat('(');
7132         add_anchor_token(')');
7133         add_anchor_token(',');
7134
7135         if (token.type != ')') {
7136                 call_argument_t *last_argument = NULL;
7137
7138                 while (true) {
7139                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
7140
7141                         argument->expression = parse_assignment_expression();
7142                         if (last_argument == NULL) {
7143                                 call->arguments = argument;
7144                         } else {
7145                                 last_argument->next = argument;
7146                         }
7147                         last_argument = argument;
7148
7149                         if (token.type != ',')
7150                                 break;
7151                         next_token();
7152                 }
7153         }
7154         rem_anchor_token(',');
7155         rem_anchor_token(')');
7156         expect(')');
7157
7158         if (function_type == NULL)
7159                 return result;
7160
7161         function_parameter_t *parameter = function_type->parameters;
7162         call_argument_t      *argument  = call->arguments;
7163         if (!function_type->unspecified_parameters) {
7164                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
7165                                 parameter = parameter->next, argument = argument->next) {
7166                         check_call_argument(parameter, argument, ++pos);
7167                 }
7168
7169                 if (parameter != NULL) {
7170                         errorf(HERE, "too few arguments to function '%E'", expression);
7171                 } else if (argument != NULL && !function_type->variadic) {
7172                         errorf(HERE, "too many arguments to function '%E'", expression);
7173                 }
7174         }
7175
7176         /* do default promotion */
7177         for( ; argument != NULL; argument = argument->next) {
7178                 type_t *type = argument->expression->base.type;
7179
7180                 type = get_default_promoted_type(type);
7181
7182                 argument->expression
7183                         = create_implicit_cast(argument->expression, type);
7184         }
7185
7186         check_format(&result->call);
7187
7188         if (warning.aggregate_return &&
7189             is_type_compound(skip_typeref(function_type->return_type))) {
7190                 warningf(&result->base.source_position,
7191                          "function call has aggregate value");
7192         }
7193
7194         return result;
7195 end_error:
7196         return create_invalid_expression();
7197 }
7198
7199 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
7200
7201 static bool same_compound_type(const type_t *type1, const type_t *type2)
7202 {
7203         return
7204                 is_type_compound(type1) &&
7205                 type1->kind == type2->kind &&
7206                 type1->compound.declaration == type2->compound.declaration;
7207 }
7208
7209 /**
7210  * Parse a conditional expression, ie. 'expression ? ... : ...'.
7211  *
7212  * @param expression  the conditional expression
7213  */
7214 static expression_t *parse_conditional_expression(unsigned precedence,
7215                                                   expression_t *expression)
7216 {
7217         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
7218
7219         conditional_expression_t *conditional = &result->conditional;
7220         conditional->base.source_position = *HERE;
7221         conditional->condition            = expression;
7222
7223         eat('?');
7224         add_anchor_token(':');
7225
7226         /* 6.5.15.2 */
7227         type_t *const condition_type_orig = expression->base.type;
7228         type_t *const condition_type      = skip_typeref(condition_type_orig);
7229         if (!is_type_scalar(condition_type) && is_type_valid(condition_type)) {
7230                 type_error("expected a scalar type in conditional condition",
7231                            &expression->base.source_position, condition_type_orig);
7232         }
7233
7234         expression_t *true_expression = expression;
7235         bool          gnu_cond = false;
7236         if ((c_mode & _GNUC) && token.type == ':') {
7237                 gnu_cond = true;
7238         } else
7239                 true_expression = parse_expression();
7240         rem_anchor_token(':');
7241         expect(':');
7242         expression_t *false_expression = parse_sub_expression(precedence);
7243
7244         type_t *const orig_true_type  = true_expression->base.type;
7245         type_t *const orig_false_type = false_expression->base.type;
7246         type_t *const true_type       = skip_typeref(orig_true_type);
7247         type_t *const false_type      = skip_typeref(orig_false_type);
7248
7249         /* 6.5.15.3 */
7250         type_t *result_type;
7251         if (is_type_atomic(true_type, ATOMIC_TYPE_VOID) ||
7252                 is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7253                 if (!is_type_atomic(true_type, ATOMIC_TYPE_VOID)
7254                     || !is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7255                         warningf(&conditional->base.source_position,
7256                                         "ISO C forbids conditional expression with only one void side");
7257                 }
7258                 result_type = type_void;
7259         } else if (is_type_arithmetic(true_type)
7260                    && is_type_arithmetic(false_type)) {
7261                 result_type = semantic_arithmetic(true_type, false_type);
7262
7263                 true_expression  = create_implicit_cast(true_expression, result_type);
7264                 false_expression = create_implicit_cast(false_expression, result_type);
7265
7266                 conditional->true_expression  = true_expression;
7267                 conditional->false_expression = false_expression;
7268                 conditional->base.type        = result_type;
7269         } else if (same_compound_type(true_type, false_type)) {
7270                 /* just take 1 of the 2 types */
7271                 result_type = true_type;
7272         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
7273                 type_t *pointer_type;
7274                 type_t *other_type;
7275                 expression_t *other_expression;
7276                 if (is_type_pointer(true_type) &&
7277                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
7278                         pointer_type     = true_type;
7279                         other_type       = false_type;
7280                         other_expression = false_expression;
7281                 } else {
7282                         pointer_type     = false_type;
7283                         other_type       = true_type;
7284                         other_expression = true_expression;
7285                 }
7286
7287                 if (is_null_pointer_constant(other_expression)) {
7288                         result_type = pointer_type;
7289                 } else if (is_type_pointer(other_type)) {
7290                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
7291                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
7292
7293                         type_t *to;
7294                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
7295                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
7296                                 to = type_void;
7297                         } else if (types_compatible(get_unqualified_type(to1),
7298                                                     get_unqualified_type(to2))) {
7299                                 to = to1;
7300                         } else {
7301                                 warningf(&conditional->base.source_position,
7302                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
7303                                         true_type, false_type);
7304                                 to = type_void;
7305                         }
7306
7307                         type_t *const type =
7308                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
7309                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
7310                 } else if (is_type_integer(other_type)) {
7311                         warningf(&conditional->base.source_position,
7312                                         "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
7313                         result_type = pointer_type;
7314                 } else {
7315                         type_error_incompatible("while parsing conditional",
7316                                         &expression->base.source_position, true_type, false_type);
7317                         result_type = type_error_type;
7318                 }
7319         } else {
7320                 /* TODO: one pointer to void*, other some pointer */
7321
7322                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
7323                         type_error_incompatible("while parsing conditional",
7324                                                 &conditional->base.source_position, true_type,
7325                                                 false_type);
7326                 }
7327                 result_type = type_error_type;
7328         }
7329
7330         conditional->true_expression
7331                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
7332         conditional->false_expression
7333                 = create_implicit_cast(false_expression, result_type);
7334         conditional->base.type = result_type;
7335         return result;
7336 end_error:
7337         return create_invalid_expression();
7338 }
7339
7340 /**
7341  * Parse an extension expression.
7342  */
7343 static expression_t *parse_extension(unsigned precedence)
7344 {
7345         eat(T___extension__);
7346
7347         /* TODO enable extensions */
7348         expression_t *expression = parse_sub_expression(precedence);
7349         /* TODO disable extensions */
7350         return expression;
7351 }
7352
7353 /**
7354  * Parse a __builtin_classify_type() expression.
7355  */
7356 static expression_t *parse_builtin_classify_type(const unsigned precedence)
7357 {
7358         eat(T___builtin_classify_type);
7359
7360         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
7361         result->base.type    = type_int;
7362
7363         expect('(');
7364         add_anchor_token(')');
7365         expression_t *expression = parse_sub_expression(precedence);
7366         rem_anchor_token(')');
7367         expect(')');
7368         result->classify_type.type_expression = expression;
7369
7370         return result;
7371 end_error:
7372         return create_invalid_expression();
7373 }
7374
7375 static bool check_pointer_arithmetic(const source_position_t *source_position,
7376                                      type_t *pointer_type,
7377                                      type_t *orig_pointer_type)
7378 {
7379         type_t *points_to = pointer_type->pointer.points_to;
7380         points_to = skip_typeref(points_to);
7381
7382         if (is_type_incomplete(points_to)) {
7383                 if (!(c_mode & _GNUC) || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7384                         errorf(source_position,
7385                                "arithmetic with pointer to incomplete type '%T' not allowed",
7386                                orig_pointer_type);
7387                         return false;
7388                 } else if (warning.pointer_arith) {
7389                         warningf(source_position,
7390                                  "pointer of type '%T' used in arithmetic",
7391                                  orig_pointer_type);
7392                 }
7393         } else if (is_type_function(points_to)) {
7394                 if (!(c_mode && _GNUC)) {
7395                         errorf(source_position,
7396                                "arithmetic with pointer to function type '%T' not allowed",
7397                                orig_pointer_type);
7398                         return false;
7399                 } else if (warning.pointer_arith) {
7400                         warningf(source_position,
7401                                  "pointer to a function '%T' used in arithmetic",
7402                                  orig_pointer_type);
7403                 }
7404         }
7405         return true;
7406 }
7407
7408 static bool is_lvalue(const expression_t *expression)
7409 {
7410         switch (expression->kind) {
7411         case EXPR_REFERENCE:
7412         case EXPR_ARRAY_ACCESS:
7413         case EXPR_SELECT:
7414         case EXPR_UNARY_DEREFERENCE:
7415                 return true;
7416
7417         default:
7418                 return false;
7419         }
7420 }
7421
7422 static void semantic_incdec(unary_expression_t *expression)
7423 {
7424         type_t *const orig_type = expression->value->base.type;
7425         type_t *const type      = skip_typeref(orig_type);
7426         if (is_type_pointer(type)) {
7427                 if (!check_pointer_arithmetic(&expression->base.source_position,
7428                                               type, orig_type)) {
7429                         return;
7430                 }
7431         } else if (!is_type_real(type) && is_type_valid(type)) {
7432                 /* TODO: improve error message */
7433                 errorf(&expression->base.source_position,
7434                        "operation needs an arithmetic or pointer type");
7435                 return;
7436         }
7437         if (!is_lvalue(expression->value)) {
7438                 /* TODO: improve error message */
7439                 errorf(&expression->base.source_position, "lvalue required as operand");
7440         }
7441         expression->base.type = orig_type;
7442 }
7443
7444 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
7445 {
7446         type_t *const orig_type = expression->value->base.type;
7447         type_t *const type      = skip_typeref(orig_type);
7448         if (!is_type_arithmetic(type)) {
7449                 if (is_type_valid(type)) {
7450                         /* TODO: improve error message */
7451                         errorf(&expression->base.source_position,
7452                                 "operation needs an arithmetic type");
7453                 }
7454                 return;
7455         }
7456
7457         expression->base.type = orig_type;
7458 }
7459
7460 static void semantic_unexpr_plus(unary_expression_t *expression)
7461 {
7462         semantic_unexpr_arithmetic(expression);
7463         if (warning.traditional)
7464                 warningf(&expression->base.source_position,
7465                         "traditional C rejects the unary plus operator");
7466 }
7467
7468 static void semantic_not(unary_expression_t *expression)
7469 {
7470         type_t *const orig_type = expression->value->base.type;
7471         type_t *const type      = skip_typeref(orig_type);
7472         if (!is_type_scalar(type) && is_type_valid(type)) {
7473                 errorf(&expression->base.source_position,
7474                        "operand of ! must be of scalar type");
7475         }
7476
7477         expression->base.type = type_int;
7478 }
7479
7480 static void semantic_unexpr_integer(unary_expression_t *expression)
7481 {
7482         type_t *const orig_type = expression->value->base.type;
7483         type_t *const type      = skip_typeref(orig_type);
7484         if (!is_type_integer(type)) {
7485                 if (is_type_valid(type)) {
7486                         errorf(&expression->base.source_position,
7487                                "operand of ~ must be of integer type");
7488                 }
7489                 return;
7490         }
7491
7492         expression->base.type = orig_type;
7493 }
7494
7495 static void semantic_dereference(unary_expression_t *expression)
7496 {
7497         type_t *const orig_type = expression->value->base.type;
7498         type_t *const type      = skip_typeref(orig_type);
7499         if (!is_type_pointer(type)) {
7500                 if (is_type_valid(type)) {
7501                         errorf(&expression->base.source_position,
7502                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
7503                 }
7504                 return;
7505         }
7506
7507         type_t *result_type   = type->pointer.points_to;
7508         result_type           = automatic_type_conversion(result_type);
7509         expression->base.type = result_type;
7510 }
7511
7512 /**
7513  * Record that an address is taken (expression represents an lvalue).
7514  *
7515  * @param expression       the expression
7516  * @param may_be_register  if true, the expression might be an register
7517  */
7518 static void set_address_taken(expression_t *expression, bool may_be_register)
7519 {
7520         if (expression->kind != EXPR_REFERENCE)
7521                 return;
7522
7523         declaration_t *const declaration = expression->reference.declaration;
7524         /* happens for parse errors */
7525         if (declaration == NULL)
7526                 return;
7527
7528         if (declaration->storage_class == STORAGE_CLASS_REGISTER && !may_be_register) {
7529                 errorf(&expression->base.source_position,
7530                                 "address of register variable '%Y' requested",
7531                                 declaration->symbol);
7532         } else {
7533                 declaration->address_taken = 1;
7534         }
7535 }
7536
7537 /**
7538  * Check the semantic of the address taken expression.
7539  */
7540 static void semantic_take_addr(unary_expression_t *expression)
7541 {
7542         expression_t *value = expression->value;
7543         value->base.type    = revert_automatic_type_conversion(value);
7544
7545         type_t *orig_type = value->base.type;
7546         if (!is_type_valid(orig_type))
7547                 return;
7548
7549         set_address_taken(value, false);
7550
7551         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
7552 }
7553
7554 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc)   \
7555 static expression_t *parse_##unexpression_type(unsigned precedence)            \
7556 {                                                                              \
7557         expression_t *unary_expression                                             \
7558                 = allocate_expression_zero(unexpression_type);                         \
7559         unary_expression->base.source_position = *HERE;                            \
7560         eat(token_type);                                                           \
7561         unary_expression->unary.value = parse_sub_expression(precedence);          \
7562                                                                                    \
7563         sfunc(&unary_expression->unary);                                           \
7564                                                                                    \
7565         return unary_expression;                                                   \
7566 }
7567
7568 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
7569                                semantic_unexpr_arithmetic)
7570 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
7571                                semantic_unexpr_plus)
7572 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
7573                                semantic_not)
7574 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
7575                                semantic_dereference)
7576 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
7577                                semantic_take_addr)
7578 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
7579                                semantic_unexpr_integer)
7580 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
7581                                semantic_incdec)
7582 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
7583                                semantic_incdec)
7584
7585 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
7586                                                sfunc)                         \
7587 static expression_t *parse_##unexpression_type(unsigned precedence,           \
7588                                                expression_t *left)            \
7589 {                                                                             \
7590         (void) precedence;                                                        \
7591                                                                               \
7592         expression_t *unary_expression                                            \
7593                 = allocate_expression_zero(unexpression_type);                        \
7594         unary_expression->base.source_position = *HERE;                           \
7595         eat(token_type);                                                          \
7596         unary_expression->unary.value          = left;                            \
7597                                                                                   \
7598         sfunc(&unary_expression->unary);                                          \
7599                                                                               \
7600         return unary_expression;                                                  \
7601 }
7602
7603 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
7604                                        EXPR_UNARY_POSTFIX_INCREMENT,
7605                                        semantic_incdec)
7606 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
7607                                        EXPR_UNARY_POSTFIX_DECREMENT,
7608                                        semantic_incdec)
7609
7610 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
7611 {
7612         /* TODO: handle complex + imaginary types */
7613
7614         /* § 6.3.1.8 Usual arithmetic conversions */
7615         if (type_left == type_long_double || type_right == type_long_double) {
7616                 return type_long_double;
7617         } else if (type_left == type_double || type_right == type_double) {
7618                 return type_double;
7619         } else if (type_left == type_float || type_right == type_float) {
7620                 return type_float;
7621         }
7622
7623         type_left  = promote_integer(type_left);
7624         type_right = promote_integer(type_right);
7625
7626         if (type_left == type_right)
7627                 return type_left;
7628
7629         bool const signed_left  = is_type_signed(type_left);
7630         bool const signed_right = is_type_signed(type_right);
7631         int const  rank_left    = get_rank(type_left);
7632         int const  rank_right   = get_rank(type_right);
7633
7634         if (signed_left == signed_right)
7635                 return rank_left >= rank_right ? type_left : type_right;
7636
7637         int     s_rank;
7638         int     u_rank;
7639         type_t *s_type;
7640         type_t *u_type;
7641         if (signed_left) {
7642                 s_rank = rank_left;
7643                 s_type = type_left;
7644                 u_rank = rank_right;
7645                 u_type = type_right;
7646         } else {
7647                 s_rank = rank_right;
7648                 s_type = type_right;
7649                 u_rank = rank_left;
7650                 u_type = type_left;
7651         }
7652
7653         if (u_rank >= s_rank)
7654                 return u_type;
7655
7656         /* casting rank to atomic_type_kind is a bit hacky, but makes things
7657          * easier here... */
7658         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
7659                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
7660                 return s_type;
7661
7662         switch (s_rank) {
7663                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
7664                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
7665                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
7666
7667                 default: panic("invalid atomic type");
7668         }
7669 }
7670
7671 /**
7672  * Check the semantic restrictions for a binary expression.
7673  */
7674 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
7675 {
7676         expression_t *const left            = expression->left;
7677         expression_t *const right           = expression->right;
7678         type_t       *const orig_type_left  = left->base.type;
7679         type_t       *const orig_type_right = right->base.type;
7680         type_t       *const type_left       = skip_typeref(orig_type_left);
7681         type_t       *const type_right      = skip_typeref(orig_type_right);
7682
7683         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7684                 /* TODO: improve error message */
7685                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7686                         errorf(&expression->base.source_position,
7687                                "operation needs arithmetic types");
7688                 }
7689                 return;
7690         }
7691
7692         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7693         expression->left      = create_implicit_cast(left, arithmetic_type);
7694         expression->right     = create_implicit_cast(right, arithmetic_type);
7695         expression->base.type = arithmetic_type;
7696 }
7697
7698 static void warn_div_by_zero(binary_expression_t const *const expression)
7699 {
7700         if (warning.div_by_zero                       &&
7701             is_type_integer(expression->base.type)    &&
7702             is_constant_expression(expression->right) &&
7703             fold_constant(expression->right) == 0) {
7704                 warningf(&expression->base.source_position, "division by zero");
7705         }
7706 }
7707
7708 /**
7709  * Check the semantic restrictions for a div/mod expression.
7710  */
7711 static void semantic_divmod_arithmetic(binary_expression_t *expression) {
7712         semantic_binexpr_arithmetic(expression);
7713         warn_div_by_zero(expression);
7714 }
7715
7716 static void semantic_shift_op(binary_expression_t *expression)
7717 {
7718         expression_t *const left            = expression->left;
7719         expression_t *const right           = expression->right;
7720         type_t       *const orig_type_left  = left->base.type;
7721         type_t       *const orig_type_right = right->base.type;
7722         type_t       *      type_left       = skip_typeref(orig_type_left);
7723         type_t       *      type_right      = skip_typeref(orig_type_right);
7724
7725         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
7726                 /* TODO: improve error message */
7727                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7728                         errorf(&expression->base.source_position,
7729                                "operands of shift operation must have integer types");
7730                 }
7731                 return;
7732         }
7733
7734         type_left  = promote_integer(type_left);
7735         type_right = promote_integer(type_right);
7736
7737         expression->left      = create_implicit_cast(left, type_left);
7738         expression->right     = create_implicit_cast(right, type_right);
7739         expression->base.type = type_left;
7740 }
7741
7742 static void semantic_add(binary_expression_t *expression)
7743 {
7744         expression_t *const left            = expression->left;
7745         expression_t *const right           = expression->right;
7746         type_t       *const orig_type_left  = left->base.type;
7747         type_t       *const orig_type_right = right->base.type;
7748         type_t       *const type_left       = skip_typeref(orig_type_left);
7749         type_t       *const type_right      = skip_typeref(orig_type_right);
7750
7751         /* § 6.5.6 */
7752         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7753                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7754                 expression->left  = create_implicit_cast(left, arithmetic_type);
7755                 expression->right = create_implicit_cast(right, arithmetic_type);
7756                 expression->base.type = arithmetic_type;
7757                 return;
7758         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7759                 check_pointer_arithmetic(&expression->base.source_position,
7760                                          type_left, orig_type_left);
7761                 expression->base.type = type_left;
7762         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
7763                 check_pointer_arithmetic(&expression->base.source_position,
7764                                          type_right, orig_type_right);
7765                 expression->base.type = type_right;
7766         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7767                 errorf(&expression->base.source_position,
7768                        "invalid operands to binary + ('%T', '%T')",
7769                        orig_type_left, orig_type_right);
7770         }
7771 }
7772
7773 static void semantic_sub(binary_expression_t *expression)
7774 {
7775         expression_t            *const left            = expression->left;
7776         expression_t            *const right           = expression->right;
7777         type_t                  *const orig_type_left  = left->base.type;
7778         type_t                  *const orig_type_right = right->base.type;
7779         type_t                  *const type_left       = skip_typeref(orig_type_left);
7780         type_t                  *const type_right      = skip_typeref(orig_type_right);
7781         source_position_t const *const pos             = &expression->base.source_position;
7782
7783         /* § 5.6.5 */
7784         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7785                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7786                 expression->left        = create_implicit_cast(left, arithmetic_type);
7787                 expression->right       = create_implicit_cast(right, arithmetic_type);
7788                 expression->base.type =  arithmetic_type;
7789                 return;
7790         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7791                 check_pointer_arithmetic(&expression->base.source_position,
7792                                          type_left, orig_type_left);
7793                 expression->base.type = type_left;
7794         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7795                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
7796                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
7797                 if (!types_compatible(unqual_left, unqual_right)) {
7798                         errorf(pos,
7799                                "subtracting pointers to incompatible types '%T' and '%T'",
7800                                orig_type_left, orig_type_right);
7801                 } else if (!is_type_object(unqual_left)) {
7802                         if (is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
7803                                 warningf(pos, "subtracting pointers to void");
7804                         } else {
7805                                 errorf(pos, "subtracting pointers to non-object types '%T'",
7806                                        orig_type_left);
7807                         }
7808                 }
7809                 expression->base.type = type_ptrdiff_t;
7810         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7811                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
7812                        orig_type_left, orig_type_right);
7813         }
7814 }
7815
7816 /**
7817  * Check the semantics of comparison expressions.
7818  *
7819  * @param expression   The expression to check.
7820  */
7821 static void semantic_comparison(binary_expression_t *expression)
7822 {
7823         expression_t *left            = expression->left;
7824         expression_t *right           = expression->right;
7825         type_t       *orig_type_left  = left->base.type;
7826         type_t       *orig_type_right = right->base.type;
7827
7828         type_t *type_left  = skip_typeref(orig_type_left);
7829         type_t *type_right = skip_typeref(orig_type_right);
7830
7831         /* TODO non-arithmetic types */
7832         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7833                 /* test for signed vs unsigned compares */
7834                 if (warning.sign_compare &&
7835                     (expression->base.kind != EXPR_BINARY_EQUAL &&
7836                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
7837                     (is_type_signed(type_left) != is_type_signed(type_right))) {
7838
7839                         /* check if 1 of the operands is a constant, in this case we just
7840                          * check wether we can safely represent the resulting constant in
7841                          * the type of the other operand. */
7842                         expression_t *const_expr = NULL;
7843                         expression_t *other_expr = NULL;
7844
7845                         if (is_constant_expression(left)) {
7846                                 const_expr = left;
7847                                 other_expr = right;
7848                         } else if (is_constant_expression(right)) {
7849                                 const_expr = right;
7850                                 other_expr = left;
7851                         }
7852
7853                         if (const_expr != NULL) {
7854                                 type_t *other_type = skip_typeref(other_expr->base.type);
7855                                 long    val        = fold_constant(const_expr);
7856                                 /* TODO: check if val can be represented by other_type */
7857                                 (void) other_type;
7858                                 (void) val;
7859                         }
7860                         warningf(&expression->base.source_position,
7861                                  "comparison between signed and unsigned");
7862                 }
7863                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7864                 expression->left        = create_implicit_cast(left, arithmetic_type);
7865                 expression->right       = create_implicit_cast(right, arithmetic_type);
7866                 expression->base.type   = arithmetic_type;
7867                 if (warning.float_equal &&
7868                     (expression->base.kind == EXPR_BINARY_EQUAL ||
7869                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
7870                     is_type_float(arithmetic_type)) {
7871                         warningf(&expression->base.source_position,
7872                                  "comparing floating point with == or != is unsafe");
7873                 }
7874         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7875                 /* TODO check compatibility */
7876         } else if (is_type_pointer(type_left)) {
7877                 expression->right = create_implicit_cast(right, type_left);
7878         } else if (is_type_pointer(type_right)) {
7879                 expression->left = create_implicit_cast(left, type_right);
7880         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7881                 type_error_incompatible("invalid operands in comparison",
7882                                         &expression->base.source_position,
7883                                         type_left, type_right);
7884         }
7885         expression->base.type = type_int;
7886 }
7887
7888 /**
7889  * Checks if a compound type has constant fields.
7890  */
7891 static bool has_const_fields(const compound_type_t *type)
7892 {
7893         const scope_t       *scope       = &type->declaration->scope;
7894         const declaration_t *declaration = scope->declarations;
7895
7896         for (; declaration != NULL; declaration = declaration->next) {
7897                 if (declaration->namespc != NAMESPACE_NORMAL)
7898                         continue;
7899
7900                 const type_t *decl_type = skip_typeref(declaration->type);
7901                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
7902                         return true;
7903         }
7904         /* TODO */
7905         return false;
7906 }
7907
7908 static bool is_valid_assignment_lhs(expression_t const* const left)
7909 {
7910         type_t *const orig_type_left = revert_automatic_type_conversion(left);
7911         type_t *const type_left      = skip_typeref(orig_type_left);
7912
7913         if (!is_lvalue(left)) {
7914                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
7915                        left);
7916                 return false;
7917         }
7918
7919         if (is_type_array(type_left)) {
7920                 errorf(HERE, "cannot assign to arrays ('%E')", left);
7921                 return false;
7922         }
7923         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
7924                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
7925                        orig_type_left);
7926                 return false;
7927         }
7928         if (is_type_incomplete(type_left)) {
7929                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
7930                        left, orig_type_left);
7931                 return false;
7932         }
7933         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
7934                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
7935                        left, orig_type_left);
7936                 return false;
7937         }
7938
7939         return true;
7940 }
7941
7942 static void semantic_arithmetic_assign(binary_expression_t *expression)
7943 {
7944         expression_t *left            = expression->left;
7945         expression_t *right           = expression->right;
7946         type_t       *orig_type_left  = left->base.type;
7947         type_t       *orig_type_right = right->base.type;
7948
7949         if (!is_valid_assignment_lhs(left))
7950                 return;
7951
7952         type_t *type_left  = skip_typeref(orig_type_left);
7953         type_t *type_right = skip_typeref(orig_type_right);
7954
7955         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7956                 /* TODO: improve error message */
7957                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7958                         errorf(&expression->base.source_position,
7959                                "operation needs arithmetic types");
7960                 }
7961                 return;
7962         }
7963
7964         /* combined instructions are tricky. We can't create an implicit cast on
7965          * the left side, because we need the uncasted form for the store.
7966          * The ast2firm pass has to know that left_type must be right_type
7967          * for the arithmetic operation and create a cast by itself */
7968         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7969         expression->right       = create_implicit_cast(right, arithmetic_type);
7970         expression->base.type   = type_left;
7971 }
7972
7973 static void semantic_divmod_assign(binary_expression_t *expression)
7974 {
7975         semantic_arithmetic_assign(expression);
7976         warn_div_by_zero(expression);
7977 }
7978
7979 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
7980 {
7981         expression_t *const left            = expression->left;
7982         expression_t *const right           = expression->right;
7983         type_t       *const orig_type_left  = left->base.type;
7984         type_t       *const orig_type_right = right->base.type;
7985         type_t       *const type_left       = skip_typeref(orig_type_left);
7986         type_t       *const type_right      = skip_typeref(orig_type_right);
7987
7988         if (!is_valid_assignment_lhs(left))
7989                 return;
7990
7991         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7992                 /* combined instructions are tricky. We can't create an implicit cast on
7993                  * the left side, because we need the uncasted form for the store.
7994                  * The ast2firm pass has to know that left_type must be right_type
7995                  * for the arithmetic operation and create a cast by itself */
7996                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
7997                 expression->right     = create_implicit_cast(right, arithmetic_type);
7998                 expression->base.type = type_left;
7999         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8000                 check_pointer_arithmetic(&expression->base.source_position,
8001                                          type_left, orig_type_left);
8002                 expression->base.type = type_left;
8003         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8004                 errorf(&expression->base.source_position,
8005                        "incompatible types '%T' and '%T' in assignment",
8006                        orig_type_left, orig_type_right);
8007         }
8008 }
8009
8010 /**
8011  * Check the semantic restrictions of a logical expression.
8012  */
8013 static void semantic_logical_op(binary_expression_t *expression)
8014 {
8015         expression_t *const left            = expression->left;
8016         expression_t *const right           = expression->right;
8017         type_t       *const orig_type_left  = left->base.type;
8018         type_t       *const orig_type_right = right->base.type;
8019         type_t       *const type_left       = skip_typeref(orig_type_left);
8020         type_t       *const type_right      = skip_typeref(orig_type_right);
8021
8022         if (!is_type_scalar(type_left) || !is_type_scalar(type_right)) {
8023                 /* TODO: improve error message */
8024                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8025                         errorf(&expression->base.source_position,
8026                                "operation needs scalar types");
8027                 }
8028                 return;
8029         }
8030
8031         expression->base.type = type_int;
8032 }
8033
8034 /**
8035  * Check the semantic restrictions of a binary assign expression.
8036  */
8037 static void semantic_binexpr_assign(binary_expression_t *expression)
8038 {
8039         expression_t *left           = expression->left;
8040         type_t       *orig_type_left = left->base.type;
8041
8042         if (!is_valid_assignment_lhs(left))
8043                 return;
8044
8045         assign_error_t error = semantic_assign(orig_type_left, expression->right);
8046         report_assign_error(error, orig_type_left, expression->right,
8047                         "assignment", &left->base.source_position);
8048         expression->right = create_implicit_cast(expression->right, orig_type_left);
8049         expression->base.type = orig_type_left;
8050 }
8051
8052 /**
8053  * Determine if the outermost operation (or parts thereof) of the given
8054  * expression has no effect in order to generate a warning about this fact.
8055  * Therefore in some cases this only examines some of the operands of the
8056  * expression (see comments in the function and examples below).
8057  * Examples:
8058  *   f() + 23;    // warning, because + has no effect
8059  *   x || f();    // no warning, because x controls execution of f()
8060  *   x ? y : f(); // warning, because y has no effect
8061  *   (void)x;     // no warning to be able to suppress the warning
8062  * This function can NOT be used for an "expression has definitely no effect"-
8063  * analysis. */
8064 static bool expression_has_effect(const expression_t *const expr)
8065 {
8066         switch (expr->kind) {
8067                 case EXPR_UNKNOWN:                   break;
8068                 case EXPR_INVALID:                   return true; /* do NOT warn */
8069                 case EXPR_REFERENCE:                 return false;
8070                 /* suppress the warning for microsoft __noop operations */
8071                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
8072                 case EXPR_CHARACTER_CONSTANT:        return false;
8073                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
8074                 case EXPR_STRING_LITERAL:            return false;
8075                 case EXPR_WIDE_STRING_LITERAL:       return false;
8076                 case EXPR_LABEL_ADDRESS:             return false;
8077
8078                 case EXPR_CALL: {
8079                         const call_expression_t *const call = &expr->call;
8080                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
8081                                 return true;
8082
8083                         switch (call->function->builtin_symbol.symbol->ID) {
8084                                 case T___builtin_va_end: return true;
8085                                 default:                 return false;
8086                         }
8087                 }
8088
8089                 /* Generate the warning if either the left or right hand side of a
8090                  * conditional expression has no effect */
8091                 case EXPR_CONDITIONAL: {
8092                         const conditional_expression_t *const cond = &expr->conditional;
8093                         return
8094                                 expression_has_effect(cond->true_expression) &&
8095                                 expression_has_effect(cond->false_expression);
8096                 }
8097
8098                 case EXPR_SELECT:                    return false;
8099                 case EXPR_ARRAY_ACCESS:              return false;
8100                 case EXPR_SIZEOF:                    return false;
8101                 case EXPR_CLASSIFY_TYPE:             return false;
8102                 case EXPR_ALIGNOF:                   return false;
8103
8104                 case EXPR_FUNCNAME:                  return false;
8105                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
8106                 case EXPR_BUILTIN_CONSTANT_P:        return false;
8107                 case EXPR_BUILTIN_PREFETCH:          return true;
8108                 case EXPR_OFFSETOF:                  return false;
8109                 case EXPR_VA_START:                  return true;
8110                 case EXPR_VA_ARG:                    return true;
8111                 case EXPR_STATEMENT:                 return true; // TODO
8112                 case EXPR_COMPOUND_LITERAL:          return false;
8113
8114                 case EXPR_UNARY_NEGATE:              return false;
8115                 case EXPR_UNARY_PLUS:                return false;
8116                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
8117                 case EXPR_UNARY_NOT:                 return false;
8118                 case EXPR_UNARY_DEREFERENCE:         return false;
8119                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
8120                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
8121                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
8122                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
8123                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
8124
8125                 /* Treat void casts as if they have an effect in order to being able to
8126                  * suppress the warning */
8127                 case EXPR_UNARY_CAST: {
8128                         type_t *const type = skip_typeref(expr->base.type);
8129                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
8130                 }
8131
8132                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
8133                 case EXPR_UNARY_ASSUME:              return true;
8134
8135                 case EXPR_BINARY_ADD:                return false;
8136                 case EXPR_BINARY_SUB:                return false;
8137                 case EXPR_BINARY_MUL:                return false;
8138                 case EXPR_BINARY_DIV:                return false;
8139                 case EXPR_BINARY_MOD:                return false;
8140                 case EXPR_BINARY_EQUAL:              return false;
8141                 case EXPR_BINARY_NOTEQUAL:           return false;
8142                 case EXPR_BINARY_LESS:               return false;
8143                 case EXPR_BINARY_LESSEQUAL:          return false;
8144                 case EXPR_BINARY_GREATER:            return false;
8145                 case EXPR_BINARY_GREATEREQUAL:       return false;
8146                 case EXPR_BINARY_BITWISE_AND:        return false;
8147                 case EXPR_BINARY_BITWISE_OR:         return false;
8148                 case EXPR_BINARY_BITWISE_XOR:        return false;
8149                 case EXPR_BINARY_SHIFTLEFT:          return false;
8150                 case EXPR_BINARY_SHIFTRIGHT:         return false;
8151                 case EXPR_BINARY_ASSIGN:             return true;
8152                 case EXPR_BINARY_MUL_ASSIGN:         return true;
8153                 case EXPR_BINARY_DIV_ASSIGN:         return true;
8154                 case EXPR_BINARY_MOD_ASSIGN:         return true;
8155                 case EXPR_BINARY_ADD_ASSIGN:         return true;
8156                 case EXPR_BINARY_SUB_ASSIGN:         return true;
8157                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
8158                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
8159                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
8160                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
8161                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
8162
8163                 /* Only examine the right hand side of && and ||, because the left hand
8164                  * side already has the effect of controlling the execution of the right
8165                  * hand side */
8166                 case EXPR_BINARY_LOGICAL_AND:
8167                 case EXPR_BINARY_LOGICAL_OR:
8168                 /* Only examine the right hand side of a comma expression, because the left
8169                  * hand side has a separate warning */
8170                 case EXPR_BINARY_COMMA:
8171                         return expression_has_effect(expr->binary.right);
8172
8173                 case EXPR_BINARY_BUILTIN_EXPECT:     return true;
8174                 case EXPR_BINARY_ISGREATER:          return false;
8175                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
8176                 case EXPR_BINARY_ISLESS:             return false;
8177                 case EXPR_BINARY_ISLESSEQUAL:        return false;
8178                 case EXPR_BINARY_ISLESSGREATER:      return false;
8179                 case EXPR_BINARY_ISUNORDERED:        return false;
8180         }
8181
8182         internal_errorf(HERE, "unexpected expression");
8183 }
8184
8185 static void semantic_comma(binary_expression_t *expression)
8186 {
8187         if (warning.unused_value) {
8188                 const expression_t *const left = expression->left;
8189                 if (!expression_has_effect(left)) {
8190                         warningf(&left->base.source_position,
8191                                  "left-hand operand of comma expression has no effect");
8192                 }
8193         }
8194         expression->base.type = expression->right->base.type;
8195 }
8196
8197 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, sfunc, lr)  \
8198 static expression_t *parse_##binexpression_type(unsigned precedence,      \
8199                                                 expression_t *left)       \
8200 {                                                                         \
8201         expression_t *binexpr = allocate_expression_zero(binexpression_type); \
8202         binexpr->base.source_position = *HERE;                                \
8203         binexpr->binary.left          = left;                                 \
8204         eat(token_type);                                                      \
8205                                                                           \
8206         expression_t *right = parse_sub_expression(precedence + lr);          \
8207                                                                           \
8208         binexpr->binary.right = right;                                        \
8209         sfunc(&binexpr->binary);                                              \
8210                                                                           \
8211         return binexpr;                                                       \
8212 }
8213
8214 CREATE_BINEXPR_PARSER(',', EXPR_BINARY_COMMA,    semantic_comma, 1)
8215 CREATE_BINEXPR_PARSER('*', EXPR_BINARY_MUL,      semantic_binexpr_arithmetic, 1)
8216 CREATE_BINEXPR_PARSER('/', EXPR_BINARY_DIV,      semantic_divmod_arithmetic, 1)
8217 CREATE_BINEXPR_PARSER('%', EXPR_BINARY_MOD,      semantic_divmod_arithmetic, 1)
8218 CREATE_BINEXPR_PARSER('+', EXPR_BINARY_ADD,      semantic_add, 1)
8219 CREATE_BINEXPR_PARSER('-', EXPR_BINARY_SUB,      semantic_sub, 1)
8220 CREATE_BINEXPR_PARSER('<', EXPR_BINARY_LESS,     semantic_comparison, 1)
8221 CREATE_BINEXPR_PARSER('>', EXPR_BINARY_GREATER,  semantic_comparison, 1)
8222 CREATE_BINEXPR_PARSER('=', EXPR_BINARY_ASSIGN,   semantic_binexpr_assign, 0)
8223
8224 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,
8225                       semantic_comparison, 1)
8226 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,
8227                       semantic_comparison, 1)
8228 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,
8229                       semantic_comparison, 1)
8230 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,
8231                       semantic_comparison, 1)
8232
8233 CREATE_BINEXPR_PARSER('&', EXPR_BINARY_BITWISE_AND,
8234                       semantic_binexpr_arithmetic, 1)
8235 CREATE_BINEXPR_PARSER('|', EXPR_BINARY_BITWISE_OR,
8236                       semantic_binexpr_arithmetic, 1)
8237 CREATE_BINEXPR_PARSER('^', EXPR_BINARY_BITWISE_XOR,
8238                       semantic_binexpr_arithmetic, 1)
8239 CREATE_BINEXPR_PARSER(T_ANDAND, EXPR_BINARY_LOGICAL_AND,
8240                       semantic_logical_op, 1)
8241 CREATE_BINEXPR_PARSER(T_PIPEPIPE, EXPR_BINARY_LOGICAL_OR,
8242                       semantic_logical_op, 1)
8243 CREATE_BINEXPR_PARSER(T_LESSLESS, EXPR_BINARY_SHIFTLEFT,
8244                       semantic_shift_op, 1)
8245 CREATE_BINEXPR_PARSER(T_GREATERGREATER, EXPR_BINARY_SHIFTRIGHT,
8246                       semantic_shift_op, 1)
8247 CREATE_BINEXPR_PARSER(T_PLUSEQUAL, EXPR_BINARY_ADD_ASSIGN,
8248                       semantic_arithmetic_addsubb_assign, 0)
8249 CREATE_BINEXPR_PARSER(T_MINUSEQUAL, EXPR_BINARY_SUB_ASSIGN,
8250                       semantic_arithmetic_addsubb_assign, 0)
8251 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL, EXPR_BINARY_MUL_ASSIGN,
8252                       semantic_arithmetic_assign, 0)
8253 CREATE_BINEXPR_PARSER(T_SLASHEQUAL, EXPR_BINARY_DIV_ASSIGN,
8254                       semantic_divmod_assign, 0)
8255 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL, EXPR_BINARY_MOD_ASSIGN,
8256                       semantic_divmod_assign, 0)
8257 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL, EXPR_BINARY_SHIFTLEFT_ASSIGN,
8258                       semantic_arithmetic_assign, 0)
8259 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL, EXPR_BINARY_SHIFTRIGHT_ASSIGN,
8260                       semantic_arithmetic_assign, 0)
8261 CREATE_BINEXPR_PARSER(T_ANDEQUAL, EXPR_BINARY_BITWISE_AND_ASSIGN,
8262                       semantic_arithmetic_assign, 0)
8263 CREATE_BINEXPR_PARSER(T_PIPEEQUAL, EXPR_BINARY_BITWISE_OR_ASSIGN,
8264                       semantic_arithmetic_assign, 0)
8265 CREATE_BINEXPR_PARSER(T_CARETEQUAL, EXPR_BINARY_BITWISE_XOR_ASSIGN,
8266                       semantic_arithmetic_assign, 0)
8267
8268 static expression_t *parse_sub_expression(unsigned precedence)
8269 {
8270         if (token.type < 0) {
8271                 return expected_expression_error();
8272         }
8273
8274         expression_parser_function_t *parser
8275                 = &expression_parsers[token.type];
8276         source_position_t             source_position = token.source_position;
8277         expression_t                 *left;
8278
8279         if (parser->parser != NULL) {
8280                 left = parser->parser(parser->precedence);
8281         } else {
8282                 left = parse_primary_expression();
8283         }
8284         assert(left != NULL);
8285         left->base.source_position = source_position;
8286
8287         while(true) {
8288                 if (token.type < 0) {
8289                         return expected_expression_error();
8290                 }
8291
8292                 parser = &expression_parsers[token.type];
8293                 if (parser->infix_parser == NULL)
8294                         break;
8295                 if (parser->infix_precedence < precedence)
8296                         break;
8297
8298                 left = parser->infix_parser(parser->infix_precedence, left);
8299
8300                 assert(left != NULL);
8301                 assert(left->kind != EXPR_UNKNOWN);
8302                 left->base.source_position = source_position;
8303         }
8304
8305         return left;
8306 }
8307
8308 /**
8309  * Parse an expression.
8310  */
8311 static expression_t *parse_expression(void)
8312 {
8313         return parse_sub_expression(1);
8314 }
8315
8316 /**
8317  * Register a parser for a prefix-like operator with given precedence.
8318  *
8319  * @param parser      the parser function
8320  * @param token_type  the token type of the prefix token
8321  * @param precedence  the precedence of the operator
8322  */
8323 static void register_expression_parser(parse_expression_function parser,
8324                                        int token_type, unsigned precedence)
8325 {
8326         expression_parser_function_t *entry = &expression_parsers[token_type];
8327
8328         if (entry->parser != NULL) {
8329                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
8330                 panic("trying to register multiple expression parsers for a token");
8331         }
8332         entry->parser     = parser;
8333         entry->precedence = precedence;
8334 }
8335
8336 /**
8337  * Register a parser for an infix operator with given precedence.
8338  *
8339  * @param parser      the parser function
8340  * @param token_type  the token type of the infix operator
8341  * @param precedence  the precedence of the operator
8342  */
8343 static void register_infix_parser(parse_expression_infix_function parser,
8344                 int token_type, unsigned precedence)
8345 {
8346         expression_parser_function_t *entry = &expression_parsers[token_type];
8347
8348         if (entry->infix_parser != NULL) {
8349                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
8350                 panic("trying to register multiple infix expression parsers for a "
8351                       "token");
8352         }
8353         entry->infix_parser     = parser;
8354         entry->infix_precedence = precedence;
8355 }
8356
8357 /**
8358  * Initialize the expression parsers.
8359  */
8360 static void init_expression_parsers(void)
8361 {
8362         memset(&expression_parsers, 0, sizeof(expression_parsers));
8363
8364         register_infix_parser(parse_array_expression,         '[',              30);
8365         register_infix_parser(parse_call_expression,          '(',              30);
8366         register_infix_parser(parse_select_expression,        '.',              30);
8367         register_infix_parser(parse_select_expression,        T_MINUSGREATER,   30);
8368         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,
8369                                                               T_PLUSPLUS,       30);
8370         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,
8371                                                               T_MINUSMINUS,     30);
8372
8373         register_infix_parser(parse_EXPR_BINARY_MUL,          '*',              17);
8374         register_infix_parser(parse_EXPR_BINARY_DIV,          '/',              17);
8375         register_infix_parser(parse_EXPR_BINARY_MOD,          '%',              17);
8376         register_infix_parser(parse_EXPR_BINARY_ADD,          '+',              16);
8377         register_infix_parser(parse_EXPR_BINARY_SUB,          '-',              16);
8378         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,    T_LESSLESS,       15);
8379         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,   T_GREATERGREATER, 15);
8380         register_infix_parser(parse_EXPR_BINARY_LESS,         '<',              14);
8381         register_infix_parser(parse_EXPR_BINARY_GREATER,      '>',              14);
8382         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,    T_LESSEQUAL,      14);
8383         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL, T_GREATEREQUAL,   14);
8384         register_infix_parser(parse_EXPR_BINARY_EQUAL,        T_EQUALEQUAL,     13);
8385         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,
8386                                                     T_EXCLAMATIONMARKEQUAL, 13);
8387         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,  '&',              12);
8388         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,  '^',              11);
8389         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,   '|',              10);
8390         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,  T_ANDAND,          9);
8391         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,   T_PIPEPIPE,        8);
8392         register_infix_parser(parse_conditional_expression,   '?',               7);
8393         register_infix_parser(parse_EXPR_BINARY_ASSIGN,       '=',               2);
8394         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,   T_PLUSEQUAL,       2);
8395         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,   T_MINUSEQUAL,      2);
8396         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,   T_ASTERISKEQUAL,   2);
8397         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,   T_SLASHEQUAL,      2);
8398         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,   T_PERCENTEQUAL,    2);
8399         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,
8400                                                                 T_LESSLESSEQUAL, 2);
8401         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,
8402                                                           T_GREATERGREATEREQUAL, 2);
8403         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN,
8404                                                                      T_ANDEQUAL, 2);
8405         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,
8406                                                                     T_PIPEEQUAL, 2);
8407         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN,
8408                                                                    T_CARETEQUAL, 2);
8409
8410         register_infix_parser(parse_EXPR_BINARY_COMMA,        ',',               1);
8411
8412         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-',      25);
8413         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+',      25);
8414         register_expression_parser(parse_EXPR_UNARY_NOT,              '!',      25);
8415         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~',      25);
8416         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*',      25);
8417         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&',      25);
8418         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT,
8419                                                                   T_PLUSPLUS,   25);
8420         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT,
8421                                                                   T_MINUSMINUS, 25);
8422         register_expression_parser(parse_sizeof,                      T_sizeof, 25);
8423         register_expression_parser(parse_alignof,                T___alignof__, 25);
8424         register_expression_parser(parse_extension,            T___extension__, 25);
8425         register_expression_parser(parse_builtin_classify_type,
8426                                                      T___builtin_classify_type, 25);
8427 }
8428
8429 /**
8430  * Parse a asm statement arguments specification.
8431  */
8432 static asm_argument_t *parse_asm_arguments(bool is_out)
8433 {
8434         asm_argument_t *result = NULL;
8435         asm_argument_t *last   = NULL;
8436
8437         while (token.type == T_STRING_LITERAL || token.type == '[') {
8438                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
8439                 memset(argument, 0, sizeof(argument[0]));
8440
8441                 if (token.type == '[') {
8442                         eat('[');
8443                         if (token.type != T_IDENTIFIER) {
8444                                 parse_error_expected("while parsing asm argument",
8445                                                      T_IDENTIFIER, NULL);
8446                                 return NULL;
8447                         }
8448                         argument->symbol = token.v.symbol;
8449
8450                         expect(']');
8451                 }
8452
8453                 argument->constraints = parse_string_literals();
8454                 expect('(');
8455                 add_anchor_token(')');
8456                 expression_t *expression = parse_expression();
8457                 rem_anchor_token(')');
8458                 if (is_out) {
8459                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
8460                          * change size or type representation (e.g. int -> long is ok, but
8461                          * int -> float is not) */
8462                         if (expression->kind == EXPR_UNARY_CAST) {
8463                                 type_t      *const type = expression->base.type;
8464                                 type_kind_t  const kind = type->kind;
8465                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
8466                                         unsigned flags;
8467                                         unsigned size;
8468                                         if (kind == TYPE_ATOMIC) {
8469                                                 atomic_type_kind_t const akind = type->atomic.akind;
8470                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8471                                                 size  = get_atomic_type_size(akind);
8472                                         } else {
8473                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8474                                                 size  = get_atomic_type_size(get_intptr_kind());
8475                                         }
8476
8477                                         do {
8478                                                 expression_t *const value      = expression->unary.value;
8479                                                 type_t       *const value_type = value->base.type;
8480                                                 type_kind_t   const value_kind = value_type->kind;
8481
8482                                                 unsigned value_flags;
8483                                                 unsigned value_size;
8484                                                 if (value_kind == TYPE_ATOMIC) {
8485                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
8486                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8487                                                         value_size  = get_atomic_type_size(value_akind);
8488                                                 } else if (value_kind == TYPE_POINTER) {
8489                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8490                                                         value_size  = get_atomic_type_size(get_intptr_kind());
8491                                                 } else {
8492                                                         break;
8493                                                 }
8494
8495                                                 if (value_flags != flags || value_size != size)
8496                                                         break;
8497
8498                                                 expression = value;
8499                                         } while (expression->kind == EXPR_UNARY_CAST);
8500                                 }
8501                         }
8502
8503                         if (!is_lvalue(expression)) {
8504                                 errorf(&expression->base.source_position,
8505                                        "asm output argument is not an lvalue");
8506                         }
8507                 }
8508                 argument->expression = expression;
8509                 expect(')');
8510
8511                 set_address_taken(expression, true);
8512
8513                 if (last != NULL) {
8514                         last->next = argument;
8515                 } else {
8516                         result = argument;
8517                 }
8518                 last = argument;
8519
8520                 if (token.type != ',')
8521                         break;
8522                 eat(',');
8523         }
8524
8525         return result;
8526 end_error:
8527         return NULL;
8528 }
8529
8530 /**
8531  * Parse a asm statement clobber specification.
8532  */
8533 static asm_clobber_t *parse_asm_clobbers(void)
8534 {
8535         asm_clobber_t *result = NULL;
8536         asm_clobber_t *last   = NULL;
8537
8538         while(token.type == T_STRING_LITERAL) {
8539                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
8540                 clobber->clobber       = parse_string_literals();
8541
8542                 if (last != NULL) {
8543                         last->next = clobber;
8544                 } else {
8545                         result = clobber;
8546                 }
8547                 last = clobber;
8548
8549                 if (token.type != ',')
8550                         break;
8551                 eat(',');
8552         }
8553
8554         return result;
8555 }
8556
8557 /**
8558  * Parse an asm statement.
8559  */
8560 static statement_t *parse_asm_statement(void)
8561 {
8562         eat(T_asm);
8563
8564         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
8565         statement->base.source_position = token.source_position;
8566
8567         asm_statement_t *asm_statement = &statement->asms;
8568
8569         if (token.type == T_volatile) {
8570                 next_token();
8571                 asm_statement->is_volatile = true;
8572         }
8573
8574         expect('(');
8575         add_anchor_token(')');
8576         add_anchor_token(':');
8577         asm_statement->asm_text = parse_string_literals();
8578
8579         if (token.type != ':') {
8580                 rem_anchor_token(':');
8581                 goto end_of_asm;
8582         }
8583         eat(':');
8584
8585         asm_statement->outputs = parse_asm_arguments(true);
8586         if (token.type != ':') {
8587                 rem_anchor_token(':');
8588                 goto end_of_asm;
8589         }
8590         eat(':');
8591
8592         asm_statement->inputs = parse_asm_arguments(false);
8593         if (token.type != ':') {
8594                 rem_anchor_token(':');
8595                 goto end_of_asm;
8596         }
8597         rem_anchor_token(':');
8598         eat(':');
8599
8600         asm_statement->clobbers = parse_asm_clobbers();
8601
8602 end_of_asm:
8603         rem_anchor_token(')');
8604         expect(')');
8605         expect(';');
8606
8607         if (asm_statement->outputs == NULL) {
8608                 /* GCC: An 'asm' instruction without any output operands will be treated
8609                  * identically to a volatile 'asm' instruction. */
8610                 asm_statement->is_volatile = true;
8611         }
8612
8613         return statement;
8614 end_error:
8615         return create_invalid_statement();
8616 }
8617
8618 /**
8619  * Parse a case statement.
8620  */
8621 static statement_t *parse_case_statement(void)
8622 {
8623         eat(T_case);
8624
8625         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8626         source_position_t *const pos       = &statement->base.source_position;
8627
8628         *pos                             = token.source_position;
8629         statement->case_label.expression = parse_expression();
8630         if (! is_constant_expression(statement->case_label.expression)) {
8631                 errorf(pos, "case label does not reduce to an integer constant");
8632                 statement->case_label.is_bad = true;
8633         } else {
8634                 long const val = fold_constant(statement->case_label.expression);
8635                 statement->case_label.first_case = val;
8636                 statement->case_label.last_case  = val;
8637         }
8638
8639         if (c_mode & _GNUC) {
8640                 if (token.type == T_DOTDOTDOT) {
8641                         next_token();
8642                         statement->case_label.end_range = parse_expression();
8643                         if (! is_constant_expression(statement->case_label.end_range)) {
8644                                 errorf(pos, "case range does not reduce to an integer constant");
8645                                 statement->case_label.is_bad = true;
8646                         } else {
8647                                 long const val = fold_constant(statement->case_label.end_range);
8648                                 statement->case_label.last_case = val;
8649
8650                                 if (val < statement->case_label.first_case) {
8651                                         statement->case_label.is_empty = true;
8652                                         warningf(pos, "empty range specified");
8653                                 }
8654                         }
8655                 }
8656         }
8657
8658         PUSH_PARENT(statement);
8659
8660         expect(':');
8661
8662         if (current_switch != NULL) {
8663                 if (! statement->case_label.is_bad) {
8664                         /* Check for duplicate case values */
8665                         case_label_statement_t *c = &statement->case_label;
8666                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
8667                                 if (l->is_bad || l->is_empty || l->expression == NULL)
8668                                         continue;
8669
8670                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
8671                                         continue;
8672
8673                                 errorf(pos, "duplicate case value (previously used %P)",
8674                                        &l->base.source_position);
8675                                 break;
8676                         }
8677                 }
8678                 /* link all cases into the switch statement */
8679                 if (current_switch->last_case == NULL) {
8680                         current_switch->first_case      = &statement->case_label;
8681                 } else {
8682                         current_switch->last_case->next = &statement->case_label;
8683                 }
8684                 current_switch->last_case = &statement->case_label;
8685         } else {
8686                 errorf(pos, "case label not within a switch statement");
8687         }
8688
8689         statement_t *const inner_stmt = parse_statement();
8690         statement->case_label.statement = inner_stmt;
8691         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8692                 errorf(&inner_stmt->base.source_position, "declaration after case label");
8693         }
8694
8695         POP_PARENT;
8696         return statement;
8697 end_error:
8698         POP_PARENT;
8699         return create_invalid_statement();
8700 }
8701
8702 /**
8703  * Parse a default statement.
8704  */
8705 static statement_t *parse_default_statement(void)
8706 {
8707         eat(T_default);
8708
8709         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8710         statement->base.source_position = token.source_position;
8711
8712         PUSH_PARENT(statement);
8713
8714         expect(':');
8715         if (current_switch != NULL) {
8716                 const case_label_statement_t *def_label = current_switch->default_label;
8717                 if (def_label != NULL) {
8718                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
8719                                &def_label->base.source_position);
8720                 } else {
8721                         current_switch->default_label = &statement->case_label;
8722
8723                         /* link all cases into the switch statement */
8724                         if (current_switch->last_case == NULL) {
8725                                 current_switch->first_case      = &statement->case_label;
8726                         } else {
8727                                 current_switch->last_case->next = &statement->case_label;
8728                         }
8729                         current_switch->last_case = &statement->case_label;
8730                 }
8731         } else {
8732                 errorf(&statement->base.source_position,
8733                         "'default' label not within a switch statement");
8734         }
8735
8736         statement_t *const inner_stmt = parse_statement();
8737         statement->case_label.statement = inner_stmt;
8738         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8739                 errorf(&inner_stmt->base.source_position, "declaration after default label");
8740         }
8741
8742         POP_PARENT;
8743         return statement;
8744 end_error:
8745         POP_PARENT;
8746         return create_invalid_statement();
8747 }
8748
8749 /**
8750  * Parse a label statement.
8751  */
8752 static statement_t *parse_label_statement(void)
8753 {
8754         assert(token.type == T_IDENTIFIER);
8755         symbol_t *symbol = token.v.symbol;
8756         next_token();
8757
8758         declaration_t *label = get_label(symbol);
8759
8760         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
8761         statement->base.source_position = token.source_position;
8762         statement->label.label          = label;
8763
8764         PUSH_PARENT(statement);
8765
8766         /* if statement is already set then the label is defined twice,
8767          * otherwise it was just mentioned in a goto/local label declaration so far */
8768         if (label->init.statement != NULL) {
8769                 errorf(HERE, "duplicate label '%Y' (declared %P)",
8770                        symbol, &label->source_position);
8771         } else {
8772                 label->source_position = token.source_position;
8773                 label->init.statement  = statement;
8774         }
8775
8776         eat(':');
8777
8778         if (token.type == '}') {
8779                 /* TODO only warn? */
8780                 if (false) {
8781                         warningf(HERE, "label at end of compound statement");
8782                         statement->label.statement = create_empty_statement();
8783                 } else {
8784                         errorf(HERE, "label at end of compound statement");
8785                         statement->label.statement = create_invalid_statement();
8786                 }
8787         } else if (token.type == ';') {
8788                 /* Eat an empty statement here, to avoid the warning about an empty
8789                  * statement after a label.  label:; is commonly used to have a label
8790                  * before a closing brace. */
8791                 statement->label.statement = create_empty_statement();
8792                 next_token();
8793         } else {
8794                 statement_t *const inner_stmt = parse_statement();
8795                 statement->label.statement = inner_stmt;
8796                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
8797                         errorf(&inner_stmt->base.source_position, "declaration after label");
8798                 }
8799         }
8800
8801         /* remember the labels in a list for later checking */
8802         if (label_last == NULL) {
8803                 label_first = &statement->label;
8804         } else {
8805                 label_last->next = &statement->label;
8806         }
8807         label_last = &statement->label;
8808
8809         POP_PARENT;
8810         return statement;
8811 }
8812
8813 /**
8814  * Parse an if statement.
8815  */
8816 static statement_t *parse_if(void)
8817 {
8818         eat(T_if);
8819
8820         statement_t *statement          = allocate_statement_zero(STATEMENT_IF);
8821         statement->base.source_position = token.source_position;
8822
8823         PUSH_PARENT(statement);
8824
8825         expect('(');
8826         add_anchor_token(')');
8827         statement->ifs.condition = parse_expression();
8828         rem_anchor_token(')');
8829         expect(')');
8830
8831         add_anchor_token(T_else);
8832         statement->ifs.true_statement = parse_statement();
8833         rem_anchor_token(T_else);
8834
8835         if (token.type == T_else) {
8836                 next_token();
8837                 statement->ifs.false_statement = parse_statement();
8838         }
8839
8840         POP_PARENT;
8841         return statement;
8842 end_error:
8843         POP_PARENT;
8844         return create_invalid_statement();
8845 }
8846
8847 /**
8848  * Check that all enums are handled in a switch.
8849  *
8850  * @param statement  the switch statement to check
8851  */
8852 static void check_enum_cases(const switch_statement_t *statement) {
8853         const type_t *type = skip_typeref(statement->expression->base.type);
8854         if (! is_type_enum(type))
8855                 return;
8856         const enum_type_t *enumt = &type->enumt;
8857
8858         /* if we have a default, no warnings */
8859         if (statement->default_label != NULL)
8860                 return;
8861
8862         /* FIXME: calculation of value should be done while parsing */
8863         const declaration_t *declaration;
8864         long last_value = -1;
8865         for (declaration = enumt->declaration->next;
8866              declaration != NULL && declaration->storage_class == STORAGE_CLASS_ENUM_ENTRY;
8867                  declaration = declaration->next) {
8868                 const expression_t *expression = declaration->init.enum_value;
8869                 long                value      = expression != NULL ? fold_constant(expression) : last_value + 1;
8870                 bool                found      = false;
8871                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
8872                         if (l->expression == NULL)
8873                                 continue;
8874                         if (l->first_case <= value && value <= l->last_case) {
8875                                 found = true;
8876                                 break;
8877                         }
8878                 }
8879                 if (! found) {
8880                         warningf(&statement->base.source_position,
8881                                 "enumeration value '%Y' not handled in switch", declaration->symbol);
8882                 }
8883                 last_value = value;
8884         }
8885 }
8886
8887 /**
8888  * Parse a switch statement.
8889  */
8890 static statement_t *parse_switch(void)
8891 {
8892         eat(T_switch);
8893
8894         statement_t *statement          = allocate_statement_zero(STATEMENT_SWITCH);
8895         statement->base.source_position = token.source_position;
8896
8897         PUSH_PARENT(statement);
8898
8899         expect('(');
8900         add_anchor_token(')');
8901         expression_t *const expr = parse_expression();
8902         type_t       *      type = skip_typeref(expr->base.type);
8903         if (is_type_integer(type)) {
8904                 type = promote_integer(type);
8905                 if (warning.traditional) {
8906                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
8907                                 warningf(&expr->base.source_position,
8908                                         "'%T' switch expression not converted to '%T' in ISO C",
8909                                         type, type_int);
8910                         }
8911                 }
8912         } else if (is_type_valid(type)) {
8913                 errorf(&expr->base.source_position,
8914                        "switch quantity is not an integer, but '%T'", type);
8915                 type = type_error_type;
8916         }
8917         statement->switchs.expression = create_implicit_cast(expr, type);
8918         expect(')');
8919         rem_anchor_token(')');
8920
8921         switch_statement_t *rem = current_switch;
8922         current_switch          = &statement->switchs;
8923         statement->switchs.body = parse_statement();
8924         current_switch          = rem;
8925
8926         if (warning.switch_default &&
8927             statement->switchs.default_label == NULL) {
8928                 warningf(&statement->base.source_position, "switch has no default case");
8929         }
8930         if (warning.switch_enum)
8931                 check_enum_cases(&statement->switchs);
8932
8933         POP_PARENT;
8934         return statement;
8935 end_error:
8936         POP_PARENT;
8937         return create_invalid_statement();
8938 }
8939
8940 static statement_t *parse_loop_body(statement_t *const loop)
8941 {
8942         statement_t *const rem = current_loop;
8943         current_loop = loop;
8944
8945         statement_t *const body = parse_statement();
8946
8947         current_loop = rem;
8948         return body;
8949 }
8950
8951 /**
8952  * Parse a while statement.
8953  */
8954 static statement_t *parse_while(void)
8955 {
8956         eat(T_while);
8957
8958         statement_t *statement          = allocate_statement_zero(STATEMENT_WHILE);
8959         statement->base.source_position = token.source_position;
8960
8961         PUSH_PARENT(statement);
8962
8963         expect('(');
8964         add_anchor_token(')');
8965         statement->whiles.condition = parse_expression();
8966         rem_anchor_token(')');
8967         expect(')');
8968
8969         statement->whiles.body = parse_loop_body(statement);
8970
8971         POP_PARENT;
8972         return statement;
8973 end_error:
8974         POP_PARENT;
8975         return create_invalid_statement();
8976 }
8977
8978 /**
8979  * Parse a do statement.
8980  */
8981 static statement_t *parse_do(void)
8982 {
8983         eat(T_do);
8984
8985         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
8986         statement->base.source_position = token.source_position;
8987
8988         PUSH_PARENT(statement)
8989
8990         add_anchor_token(T_while);
8991         statement->do_while.body = parse_loop_body(statement);
8992         rem_anchor_token(T_while);
8993
8994         expect(T_while);
8995         expect('(');
8996         add_anchor_token(')');
8997         statement->do_while.condition = parse_expression();
8998         rem_anchor_token(')');
8999         expect(')');
9000         expect(';');
9001
9002         POP_PARENT;
9003         return statement;
9004 end_error:
9005         POP_PARENT;
9006         return create_invalid_statement();
9007 }
9008
9009 /**
9010  * Parse a for statement.
9011  */
9012 static statement_t *parse_for(void)
9013 {
9014         eat(T_for);
9015
9016         statement_t *statement          = allocate_statement_zero(STATEMENT_FOR);
9017         statement->base.source_position = token.source_position;
9018
9019         PUSH_PARENT(statement);
9020
9021         int      top        = environment_top();
9022         scope_t *last_scope = scope;
9023         set_scope(&statement->fors.scope);
9024
9025         expect('(');
9026         add_anchor_token(')');
9027
9028         if (token.type != ';') {
9029                 if (is_declaration_specifier(&token, false)) {
9030                         parse_declaration(record_declaration);
9031                 } else {
9032                         add_anchor_token(';');
9033                         expression_t *const init = parse_expression();
9034                         statement->fors.initialisation = init;
9035                         if (warning.unused_value && !expression_has_effect(init)) {
9036                                 warningf(&init->base.source_position,
9037                                          "initialisation of 'for'-statement has no effect");
9038                         }
9039                         rem_anchor_token(';');
9040                         expect(';');
9041                 }
9042         } else {
9043                 expect(';');
9044         }
9045
9046         if (token.type != ';') {
9047                 add_anchor_token(';');
9048                 statement->fors.condition = parse_expression();
9049                 rem_anchor_token(';');
9050         }
9051         expect(';');
9052         if (token.type != ')') {
9053                 expression_t *const step = parse_expression();
9054                 statement->fors.step = step;
9055                 if (warning.unused_value && !expression_has_effect(step)) {
9056                         warningf(&step->base.source_position,
9057                                  "step of 'for'-statement has no effect");
9058                 }
9059         }
9060         rem_anchor_token(')');
9061         expect(')');
9062         statement->fors.body = parse_loop_body(statement);
9063
9064         assert(scope == &statement->fors.scope);
9065         set_scope(last_scope);
9066         environment_pop_to(top);
9067
9068         POP_PARENT;
9069         return statement;
9070
9071 end_error:
9072         POP_PARENT;
9073         rem_anchor_token(')');
9074         assert(scope == &statement->fors.scope);
9075         set_scope(last_scope);
9076         environment_pop_to(top);
9077
9078         return create_invalid_statement();
9079 }
9080
9081 /**
9082  * Parse a goto statement.
9083  */
9084 static statement_t *parse_goto(void)
9085 {
9086         source_position_t source_position = token.source_position;
9087         eat(T_goto);
9088
9089         statement_t *statement;
9090         if (c_mode & _GNUC && token.type == '*') {
9091                 next_token();
9092                 expression_t *expression = parse_expression();
9093
9094                 /* Argh: although documentation say the expression must be of type void *,
9095                  * gcc excepts anything that can be casted into void * without error */
9096                 type_t *type = expression->base.type;
9097
9098                 if (type != type_error_type) {
9099                         if (!is_type_pointer(type) && !is_type_integer(type)) {
9100                                 errorf(&source_position, "cannot convert to a pointer type");
9101                         } else if (type != type_void_ptr) {
9102                                 warningf(&source_position,
9103                                         "type of computed goto expression should be 'void*' not '%T'", type);
9104                         }
9105                         expression = create_implicit_cast(expression, type_void_ptr);
9106                 }
9107
9108                 statement                       = allocate_statement_zero(STATEMENT_GOTO);
9109                 statement->base.source_position = source_position;
9110                 statement->gotos.expression     = expression;
9111         } else {
9112                 if (token.type != T_IDENTIFIER) {
9113                         if (c_mode & _GNUC)
9114                                 parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
9115                         else
9116                                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
9117                         eat_statement();
9118                         goto end_error;
9119                 }
9120                 symbol_t *symbol = token.v.symbol;
9121                 next_token();
9122
9123                 statement                       = allocate_statement_zero(STATEMENT_GOTO);
9124                 statement->base.source_position = source_position;
9125                 statement->gotos.label          = get_label(symbol);
9126         }
9127
9128         /* remember the goto's in a list for later checking */
9129         if (goto_last == NULL) {
9130                 goto_first = &statement->gotos;
9131         } else {
9132                 goto_last->next = &statement->gotos;
9133         }
9134         goto_last = &statement->gotos;
9135
9136         expect(';');
9137
9138         return statement;
9139 end_error:
9140         return create_invalid_statement();
9141 }
9142
9143 /**
9144  * Parse a continue statement.
9145  */
9146 static statement_t *parse_continue(void)
9147 {
9148         if (current_loop == NULL) {
9149                 errorf(HERE, "continue statement not within loop");
9150         }
9151
9152         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
9153         statement->base.source_position = token.source_position;
9154
9155         eat(T_continue);
9156         expect(';');
9157
9158 end_error:
9159         return statement;
9160 }
9161
9162 /**
9163  * Parse a break statement.
9164  */
9165 static statement_t *parse_break(void)
9166 {
9167         if (current_switch == NULL && current_loop == NULL) {
9168                 errorf(HERE, "break statement not within loop or switch");
9169         }
9170
9171         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
9172         statement->base.source_position = token.source_position;
9173
9174         eat(T_break);
9175         expect(';');
9176
9177 end_error:
9178         return statement;
9179 }
9180
9181 /**
9182  * Parse a __leave statement.
9183  */
9184 static statement_t *parse_leave_statement(void)
9185 {
9186         if (current_try == NULL) {
9187                 errorf(HERE, "__leave statement not within __try");
9188         }
9189
9190         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
9191         statement->base.source_position = token.source_position;
9192
9193         eat(T___leave);
9194         expect(';');
9195
9196 end_error:
9197         return statement;
9198 }
9199
9200 /**
9201  * Check if a given declaration represents a local variable.
9202  */
9203 static bool is_local_var_declaration(const declaration_t *declaration)
9204 {
9205         switch ((storage_class_tag_t) declaration->storage_class) {
9206         case STORAGE_CLASS_AUTO:
9207         case STORAGE_CLASS_REGISTER: {
9208                 const type_t *type = skip_typeref(declaration->type);
9209                 if (is_type_function(type)) {
9210                         return false;
9211                 } else {
9212                         return true;
9213                 }
9214         }
9215         default:
9216                 return false;
9217         }
9218 }
9219
9220 /**
9221  * Check if a given declaration represents a variable.
9222  */
9223 static bool is_var_declaration(const declaration_t *declaration)
9224 {
9225         if (declaration->storage_class == STORAGE_CLASS_TYPEDEF)
9226                 return false;
9227
9228         const type_t *type = skip_typeref(declaration->type);
9229         return !is_type_function(type);
9230 }
9231
9232 /**
9233  * Check if a given expression represents a local variable.
9234  */
9235 static bool is_local_variable(const expression_t *expression)
9236 {
9237         if (expression->base.kind != EXPR_REFERENCE) {
9238                 return false;
9239         }
9240         const declaration_t *declaration = expression->reference.declaration;
9241         return is_local_var_declaration(declaration);
9242 }
9243
9244 /**
9245  * Check if a given expression represents a local variable and
9246  * return its declaration then, else return NULL.
9247  */
9248 declaration_t *expr_is_variable(const expression_t *expression)
9249 {
9250         if (expression->base.kind != EXPR_REFERENCE) {
9251                 return NULL;
9252         }
9253         declaration_t *declaration = expression->reference.declaration;
9254         if (is_var_declaration(declaration))
9255                 return declaration;
9256         return NULL;
9257 }
9258
9259 /**
9260  * Parse a return statement.
9261  */
9262 static statement_t *parse_return(void)
9263 {
9264         statement_t *statement          = allocate_statement_zero(STATEMENT_RETURN);
9265         statement->base.source_position = token.source_position;
9266
9267         eat(T_return);
9268
9269         expression_t *return_value = NULL;
9270         if (token.type != ';') {
9271                 return_value = parse_expression();
9272         }
9273
9274         const type_t *const func_type = current_function->type;
9275         assert(is_type_function(func_type));
9276         type_t *const return_type = skip_typeref(func_type->function.return_type);
9277
9278         if (return_value != NULL) {
9279                 type_t *return_value_type = skip_typeref(return_value->base.type);
9280
9281                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)
9282                                 && !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
9283                         warningf(&statement->base.source_position,
9284                                  "'return' with a value, in function returning void");
9285                         return_value = NULL;
9286                 } else {
9287                         assign_error_t error = semantic_assign(return_type, return_value);
9288                         report_assign_error(error, return_type, return_value, "'return'",
9289                                             &statement->base.source_position);
9290                         return_value = create_implicit_cast(return_value, return_type);
9291                 }
9292                 /* check for returning address of a local var */
9293                 if (return_value != NULL &&
9294                                 return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
9295                         const expression_t *expression = return_value->unary.value;
9296                         if (is_local_variable(expression)) {
9297                                 warningf(&statement->base.source_position,
9298                                          "function returns address of local variable");
9299                         }
9300                 }
9301         } else {
9302                 if (!is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
9303                         warningf(&statement->base.source_position,
9304                                  "'return' without value, in function returning non-void");
9305                 }
9306         }
9307         statement->returns.value = return_value;
9308
9309         expect(';');
9310
9311 end_error:
9312         return statement;
9313 }
9314
9315 /**
9316  * Parse a declaration statement.
9317  */
9318 static statement_t *parse_declaration_statement(void)
9319 {
9320         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
9321
9322         statement->base.source_position = token.source_position;
9323
9324         declaration_t *before = last_declaration;
9325         parse_declaration(record_declaration);
9326
9327         if (before == NULL) {
9328                 statement->declaration.declarations_begin = scope->declarations;
9329         } else {
9330                 statement->declaration.declarations_begin = before->next;
9331         }
9332         statement->declaration.declarations_end = last_declaration;
9333
9334         return statement;
9335 }
9336
9337 /**
9338  * Parse an expression statement, ie. expr ';'.
9339  */
9340 static statement_t *parse_expression_statement(void)
9341 {
9342         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
9343
9344         statement->base.source_position  = token.source_position;
9345         expression_t *const expr         = parse_expression();
9346         statement->expression.expression = expr;
9347
9348         expect(';');
9349
9350 end_error:
9351         return statement;
9352 }
9353
9354 /**
9355  * Parse a microsoft __try { } __finally { } or
9356  * __try{ } __except() { }
9357  */
9358 static statement_t *parse_ms_try_statment(void)
9359 {
9360         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
9361         statement->base.source_position  = token.source_position;
9362         eat(T___try);
9363
9364         PUSH_PARENT(statement);
9365
9366         ms_try_statement_t *rem = current_try;
9367         current_try = &statement->ms_try;
9368         statement->ms_try.try_statement = parse_compound_statement(false);
9369         current_try = rem;
9370
9371         POP_PARENT;
9372
9373         if (token.type == T___except) {
9374                 eat(T___except);
9375                 expect('(');
9376                 add_anchor_token(')');
9377                 expression_t *const expr = parse_expression();
9378                 type_t       *      type = skip_typeref(expr->base.type);
9379                 if (is_type_integer(type)) {
9380                         type = promote_integer(type);
9381                 } else if (is_type_valid(type)) {
9382                         errorf(&expr->base.source_position,
9383                                "__expect expression is not an integer, but '%T'", type);
9384                         type = type_error_type;
9385                 }
9386                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
9387                 rem_anchor_token(')');
9388                 expect(')');
9389                 statement->ms_try.final_statement = parse_compound_statement(false);
9390         } else if (token.type == T__finally) {
9391                 eat(T___finally);
9392                 statement->ms_try.final_statement = parse_compound_statement(false);
9393         } else {
9394                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
9395                 return create_invalid_statement();
9396         }
9397         return statement;
9398 end_error:
9399         return create_invalid_statement();
9400 }
9401
9402 static statement_t *parse_empty_statement(void)
9403 {
9404         if (warning.empty_statement) {
9405                 warningf(HERE, "statement is empty");
9406         }
9407         statement_t *const statement = create_empty_statement();
9408         eat(';');
9409         return statement;
9410 }
9411
9412 static statement_t *parse_local_label_declaration(void) {
9413         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
9414         statement->base.source_position = token.source_position;
9415
9416         eat(T___label__);
9417
9418         declaration_t *begin = NULL, *end = NULL;
9419
9420         while (true) {
9421                 if (token.type != T_IDENTIFIER) {
9422                         parse_error_expected("while parsing local label declaration",
9423                                 T_IDENTIFIER, NULL);
9424                         goto end_error;
9425                 }
9426                 symbol_t      *symbol      = token.v.symbol;
9427                 declaration_t *declaration = get_declaration(symbol, NAMESPACE_LOCAL_LABEL);
9428                 if (declaration != NULL) {
9429                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition at %P)",
9430                                 symbol, &declaration->source_position);
9431                 } else {
9432                         declaration = allocate_declaration_zero();
9433                         declaration->namespc         = NAMESPACE_LOCAL_LABEL;
9434                         declaration->source_position = token.source_position;
9435                         declaration->symbol          = symbol;
9436                         declaration->parent_scope    = scope;
9437                         declaration->init.statement  = NULL;
9438
9439                         if (end != NULL)
9440                                 end->next = declaration;
9441                         end = declaration;
9442                         if (begin == NULL)
9443                                 begin = declaration;
9444
9445                         local_label_push(declaration);
9446                 }
9447                 next_token();
9448
9449                 if (token.type != ',')
9450                         break;
9451                 next_token();
9452         }
9453         eat(';');
9454 end_error:
9455         statement->declaration.declarations_begin = begin;
9456         statement->declaration.declarations_end   = end;
9457         return statement;
9458 }
9459
9460 /**
9461  * Parse a statement.
9462  * There's also parse_statement() which additionally checks for
9463  * "statement has no effect" warnings
9464  */
9465 static statement_t *intern_parse_statement(void)
9466 {
9467         statement_t *statement = NULL;
9468
9469         /* declaration or statement */
9470         add_anchor_token(';');
9471         switch (token.type) {
9472         case T_IDENTIFIER: {
9473                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
9474                 if (la1_type == ':') {
9475                         statement = parse_label_statement();
9476                 } else if (is_typedef_symbol(token.v.symbol)) {
9477                         statement = parse_declaration_statement();
9478                 } else switch (la1_type) {
9479                         DECLARATION_START
9480                         case T_IDENTIFIER:
9481                         case '*':
9482                                 statement = parse_declaration_statement();
9483                                 break;
9484
9485                         default:
9486                                 statement = parse_expression_statement();
9487                                 break;
9488                 }
9489                 break;
9490         }
9491
9492         case T___extension__:
9493                 /* This can be a prefix to a declaration or an expression statement.
9494                  * We simply eat it now and parse the rest with tail recursion. */
9495                 do {
9496                         next_token();
9497                 } while (token.type == T___extension__);
9498                 statement = parse_statement();
9499                 break;
9500
9501         DECLARATION_START
9502                 statement = parse_declaration_statement();
9503                 break;
9504
9505         case T___label__:
9506                 statement = parse_local_label_declaration();
9507                 break;
9508
9509         case ';':        statement = parse_empty_statement();         break;
9510         case '{':        statement = parse_compound_statement(false); break;
9511         case T___leave:  statement = parse_leave_statement();                   break;
9512         case T___try:    statement = parse_ms_try_statment();         break;
9513         case T_asm:      statement = parse_asm_statement();           break;
9514         case T_break:    statement = parse_break();                   break;
9515         case T_case:     statement = parse_case_statement();          break;
9516         case T_continue: statement = parse_continue();                break;
9517         case T_default:  statement = parse_default_statement();       break;
9518         case T_do:       statement = parse_do();                      break;
9519         case T_for:      statement = parse_for();                     break;
9520         case T_goto:     statement = parse_goto();                    break;
9521         case T_if:       statement = parse_if ();                     break;
9522         case T_return:   statement = parse_return();                  break;
9523         case T_switch:   statement = parse_switch();                  break;
9524         case T_while:    statement = parse_while();                   break;
9525         default:         statement = parse_expression_statement();    break;
9526         }
9527         rem_anchor_token(';');
9528
9529         assert(statement != NULL
9530                         && statement->base.source_position.input_name != NULL);
9531
9532         return statement;
9533 }
9534
9535 /**
9536  * parse a statement and emits "statement has no effect" warning if needed
9537  * (This is really a wrapper around intern_parse_statement with check for 1
9538  *  single warning. It is needed, because for statement expressions we have
9539  *  to avoid the warning on the last statement)
9540  */
9541 static statement_t *parse_statement(void)
9542 {
9543         statement_t *statement = intern_parse_statement();
9544
9545         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
9546                 expression_t *expression = statement->expression.expression;
9547                 if (!expression_has_effect(expression)) {
9548                         warningf(&expression->base.source_position,
9549                                         "statement has no effect");
9550                 }
9551         }
9552
9553         return statement;
9554 }
9555
9556 /**
9557  * Parse a compound statement.
9558  */
9559 static statement_t *parse_compound_statement(bool inside_expression_statement)
9560 {
9561         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
9562         statement->base.source_position = token.source_position;
9563
9564         PUSH_PARENT(statement);
9565
9566         eat('{');
9567         add_anchor_token('}');
9568
9569         int      top        = environment_top();
9570         int      top_local  = local_label_top();
9571         scope_t *last_scope = scope;
9572         set_scope(&statement->compound.scope);
9573
9574         statement_t **anchor            = &statement->compound.statements;
9575         bool          only_decls_so_far = true;
9576         while (token.type != '}' && token.type != T_EOF) {
9577                 statement_t *sub_statement = intern_parse_statement();
9578                 if (is_invalid_statement(sub_statement)) {
9579                         /* an error occurred. if we are at an anchor, return */
9580                         if (at_anchor())
9581                                 goto end_error;
9582                         continue;
9583                 }
9584
9585                 if (warning.declaration_after_statement) {
9586                         if (sub_statement->kind != STATEMENT_DECLARATION) {
9587                                 only_decls_so_far = false;
9588                         } else if (!only_decls_so_far) {
9589                                 warningf(&sub_statement->base.source_position,
9590                                          "ISO C90 forbids mixed declarations and code");
9591                         }
9592                 }
9593
9594                 *anchor = sub_statement;
9595
9596                 while (sub_statement->base.next != NULL)
9597                         sub_statement = sub_statement->base.next;
9598
9599                 anchor = &sub_statement->base.next;
9600         }
9601
9602         if (token.type == '}') {
9603                 next_token();
9604         } else {
9605                 errorf(&statement->base.source_position,
9606                        "end of file while looking for closing '}'");
9607         }
9608
9609         /* look over all statements again to produce no effect warnings */
9610         if (warning.unused_value) {
9611                 statement_t *sub_statement = statement->compound.statements;
9612                 for( ; sub_statement != NULL; sub_statement = sub_statement->base.next) {
9613                         if (sub_statement->kind != STATEMENT_EXPRESSION)
9614                                 continue;
9615                         /* don't emit a warning for the last expression in an expression
9616                          * statement as it has always an effect */
9617                         if (inside_expression_statement && sub_statement->base.next == NULL)
9618                                 continue;
9619
9620                         expression_t *expression = sub_statement->expression.expression;
9621                         if (!expression_has_effect(expression)) {
9622                                 warningf(&expression->base.source_position,
9623                                          "statement has no effect");
9624                         }
9625                 }
9626         }
9627
9628 end_error:
9629         rem_anchor_token('}');
9630         assert(scope == &statement->compound.scope);
9631         set_scope(last_scope);
9632         environment_pop_to(top);
9633         local_label_pop_to(top_local);
9634
9635         POP_PARENT;
9636         return statement;
9637 }
9638
9639 /**
9640  * Initialize builtin types.
9641  */
9642 static void initialize_builtin_types(void)
9643 {
9644         type_intmax_t    = make_global_typedef("__intmax_t__",      type_long_long);
9645         type_size_t      = make_global_typedef("__SIZE_TYPE__",     type_unsigned_long);
9646         type_ssize_t     = make_global_typedef("__SSIZE_TYPE__",    type_long);
9647         type_ptrdiff_t   = make_global_typedef("__PTRDIFF_TYPE__",  type_long);
9648         type_uintmax_t   = make_global_typedef("__uintmax_t__",     type_unsigned_long_long);
9649         type_uptrdiff_t  = make_global_typedef("__UPTRDIFF_TYPE__", type_unsigned_long);
9650         type_wchar_t     = make_global_typedef("__WCHAR_TYPE__",    opt_short_wchar_t ? type_unsigned_short : type_int);
9651         type_wint_t      = make_global_typedef("__WINT_TYPE__",     type_int);
9652
9653         type_intmax_t_ptr  = make_pointer_type(type_intmax_t,  TYPE_QUALIFIER_NONE);
9654         type_ptrdiff_t_ptr = make_pointer_type(type_ptrdiff_t, TYPE_QUALIFIER_NONE);
9655         type_ssize_t_ptr   = make_pointer_type(type_ssize_t,   TYPE_QUALIFIER_NONE);
9656         type_wchar_t_ptr   = make_pointer_type(type_wchar_t,   TYPE_QUALIFIER_NONE);
9657
9658         /* const version of wchar_t */
9659         type_const_wchar_t = allocate_type_zero(TYPE_TYPEDEF, &builtin_source_position);
9660         type_const_wchar_t->typedeft.declaration  = type_wchar_t->typedeft.declaration;
9661         type_const_wchar_t->base.qualifiers      |= TYPE_QUALIFIER_CONST;
9662
9663         type_const_wchar_t_ptr = make_pointer_type(type_const_wchar_t, TYPE_QUALIFIER_NONE);
9664 }
9665
9666 /**
9667  * Check for unused global static functions and variables
9668  */
9669 static void check_unused_globals(void)
9670 {
9671         if (!warning.unused_function && !warning.unused_variable)
9672                 return;
9673
9674         for (const declaration_t *decl = global_scope->declarations; decl != NULL; decl = decl->next) {
9675                 if (decl->used                  ||
9676                     decl->modifiers & DM_UNUSED ||
9677                     decl->modifiers & DM_USED   ||
9678                     decl->storage_class != STORAGE_CLASS_STATIC)
9679                         continue;
9680
9681                 type_t *const type = decl->type;
9682                 const char *s;
9683                 if (is_type_function(skip_typeref(type))) {
9684                         if (!warning.unused_function || decl->is_inline)
9685                                 continue;
9686
9687                         s = (decl->init.statement != NULL ? "defined" : "declared");
9688                 } else {
9689                         if (!warning.unused_variable)
9690                                 continue;
9691
9692                         s = "defined";
9693                 }
9694
9695                 warningf(&decl->source_position, "'%#T' %s but not used",
9696                         type, decl->symbol, s);
9697         }
9698 }
9699
9700 static void parse_global_asm(void)
9701 {
9702         eat(T_asm);
9703         expect('(');
9704
9705         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
9706         statement->base.source_position = token.source_position;
9707         statement->asms.asm_text        = parse_string_literals();
9708         statement->base.next            = unit->global_asm;
9709         unit->global_asm                = statement;
9710
9711         expect(')');
9712         expect(';');
9713
9714 end_error:;
9715 }
9716
9717 /**
9718  * Parse a translation unit.
9719  */
9720 static void parse_translation_unit(void)
9721 {
9722         for (;;) switch (token.type) {
9723                 DECLARATION_START
9724                 case T_IDENTIFIER:
9725                 case T___extension__:
9726                         parse_external_declaration();
9727                         break;
9728
9729                 case T_asm:
9730                         parse_global_asm();
9731                         break;
9732
9733                 case T_EOF:
9734                         return;
9735
9736                 case ';':
9737                         /* TODO error in strict mode */
9738                         warningf(HERE, "stray ';' outside of function");
9739                         next_token();
9740                         break;
9741
9742                 default:
9743                         errorf(HERE, "stray %K outside of function", &token);
9744                         if (token.type == '(' || token.type == '{' || token.type == '[')
9745                                 eat_until_matching_token(token.type);
9746                         next_token();
9747                         break;
9748         }
9749 }
9750
9751 /**
9752  * Parse the input.
9753  *
9754  * @return  the translation unit or NULL if errors occurred.
9755  */
9756 void start_parsing(void)
9757 {
9758         environment_stack = NEW_ARR_F(stack_entry_t, 0);
9759         label_stack       = NEW_ARR_F(stack_entry_t, 0);
9760         local_label_stack = NEW_ARR_F(stack_entry_t, 0);
9761         diagnostic_count  = 0;
9762         error_count       = 0;
9763         warning_count     = 0;
9764
9765         type_set_output(stderr);
9766         ast_set_output(stderr);
9767
9768         assert(unit == NULL);
9769         unit = allocate_ast_zero(sizeof(unit[0]));
9770
9771         assert(global_scope == NULL);
9772         global_scope = &unit->scope;
9773
9774         assert(scope == NULL);
9775         set_scope(&unit->scope);
9776
9777         initialize_builtin_types();
9778 }
9779
9780 translation_unit_t *finish_parsing(void)
9781 {
9782         assert(scope == &unit->scope);
9783         scope          = NULL;
9784         last_declaration = NULL;
9785
9786         assert(global_scope == &unit->scope);
9787         check_unused_globals();
9788         global_scope = NULL;
9789
9790         DEL_ARR_F(environment_stack);
9791         DEL_ARR_F(label_stack);
9792         DEL_ARR_F(local_label_stack);
9793
9794         translation_unit_t *result = unit;
9795         unit = NULL;
9796         return result;
9797 }
9798
9799 void parse(void)
9800 {
9801         lookahead_bufpos = 0;
9802         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
9803                 next_token();
9804         }
9805         parse_translation_unit();
9806 }
9807
9808 /**
9809  * Initialize the parser.
9810  */
9811 void init_parser(void)
9812 {
9813         if (c_mode & _MS) {
9814                 /* add predefined symbols for extended-decl-modifier */
9815                 sym_align      = symbol_table_insert("align");
9816                 sym_allocate   = symbol_table_insert("allocate");
9817                 sym_dllimport  = symbol_table_insert("dllimport");
9818                 sym_dllexport  = symbol_table_insert("dllexport");
9819                 sym_naked      = symbol_table_insert("naked");
9820                 sym_noinline   = symbol_table_insert("noinline");
9821                 sym_noreturn   = symbol_table_insert("noreturn");
9822                 sym_nothrow    = symbol_table_insert("nothrow");
9823                 sym_novtable   = symbol_table_insert("novtable");
9824                 sym_property   = symbol_table_insert("property");
9825                 sym_get        = symbol_table_insert("get");
9826                 sym_put        = symbol_table_insert("put");
9827                 sym_selectany  = symbol_table_insert("selectany");
9828                 sym_thread     = symbol_table_insert("thread");
9829                 sym_uuid       = symbol_table_insert("uuid");
9830                 sym_deprecated = symbol_table_insert("deprecated");
9831                 sym_restrict   = symbol_table_insert("restrict");
9832                 sym_noalias    = symbol_table_insert("noalias");
9833         }
9834         memset(token_anchor_set, 0, sizeof(token_anchor_set));
9835
9836         init_expression_parsers();
9837         obstack_init(&temp_obst);
9838
9839         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
9840         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
9841 }
9842
9843 /**
9844  * Terminate the parser.
9845  */
9846 void exit_parser(void)
9847 {
9848         obstack_free(&temp_obst, NULL);
9849 }