nsz Git - cparser/blob - type.c

   1 #include <config.h>
   2
   3 #include <stdio.h>
   4 #include <assert.h>
   5 #include "type_t.h"
   6 #include "type_hash.h"
   7 #include "adt/error.h"
   8
   9 static struct obstack   _type_obst;
  10 struct obstack         *type_obst = &_type_obst;
  11 static FILE            *out;
  12 static int              type_visited = 0;
  13
  14 static void intern_print_type_pre(const type_t *type, bool top);
  15 static void intern_print_type_post(const type_t *type, bool top);
  16
  17 void init_types(void)
  18 {
  19         obstack_init(type_obst);
  20 }
  21
  22 void exit_types(void)
  23 {
  24         obstack_free(type_obst, NULL);
  25 }
  26
  27 void type_set_output(FILE *stream)
  28 {
  29         out = stream;
  30 }
  31
  32 void inc_type_visited(void)
  33 {
  34         type_visited++;
  35 }
  36
  37 void print_type_qualifiers(type_qualifiers_t qualifiers)
  38 {
  39         if(qualifiers & TYPE_QUALIFIER_CONST)    fputs("const ",    out);
  40         if(qualifiers & TYPE_QUALIFIER_VOLATILE) fputs("volatile ", out);
  41         if(qualifiers & TYPE_QUALIFIER_RESTRICT) fputs("restrict ", out);
  42 }
  43
  44 static
  45 void print_atomic_type(const atomic_type_t *type)
  46 {
  47         print_type_qualifiers(type->type.qualifiers);
  48
  49         const char *s;
  50         switch(type->akind) {
  51         case ATOMIC_TYPE_INVALID:     s = "INVALIDATOMIC";      break;
  52         case ATOMIC_TYPE_VOID:        s = "void";               break;
  53         case ATOMIC_TYPE_BOOL:        s = "_Bool";              break;
  54         case ATOMIC_TYPE_CHAR:        s = "char";               break;
  55         case ATOMIC_TYPE_SCHAR:       s = "signed char";        break;
  56         case ATOMIC_TYPE_UCHAR:       s = "unsigned char";      break;
  57         case ATOMIC_TYPE_INT:         s = "int";                break;
  58         case ATOMIC_TYPE_UINT:        s = "unsigned int";       break;
  59         case ATOMIC_TYPE_SHORT:       s = "short";              break;
  60         case ATOMIC_TYPE_USHORT:      s = "unsigned short";     break;
  61         case ATOMIC_TYPE_LONG:        s = "long";               break;
  62         case ATOMIC_TYPE_ULONG:       s = "unsigned long";      break;
  63         case ATOMIC_TYPE_LONGLONG:    s = "long long";          break;
  64         case ATOMIC_TYPE_ULONGLONG:   s = "unsigned long long"; break;
  65         case ATOMIC_TYPE_LONG_DOUBLE: s = "long double";        break;
  66         case ATOMIC_TYPE_FLOAT:       s = "float";              break;
  67         case ATOMIC_TYPE_DOUBLE:      s = "double";             break;
  68         default:                      s = "UNKNOWNATOMIC";      break;
  69         }
  70         fputs(s, out);
  71 }
  72
  73 static void print_function_type_pre(const function_type_t *type, bool top)
  74 {
  75         print_type_qualifiers(type->type.qualifiers);
  76
  77         intern_print_type_pre(type->return_type, false);
  78
  79         /* don't emit braces if we're the toplevel type... */
  80         if(!top)
  81                 fputc('(', out);
  82 }
  83
  84 static void print_function_type_post(const function_type_t *type,
  85                                      const scope_t *scope, bool top)
  86 {
  87         intern_print_type_post(type->return_type, false);
  88         /* don't emit braces if we're the toplevel type... */
  89         if(!top)
  90                 fputc(')', out);
  91
  92         fputc('(', out);
  93
  94         int first = 1;
  95         if(scope == NULL) {
  96                 function_parameter_t *parameter = type->parameters;
  97                 for( ; parameter != NULL; parameter = parameter->next) {
  98                         if(first) {
  99                                 first = 0;
 100                         } else {
 101                                 fputs(", ", out);
 102                         }
 103                         print_type(parameter->type);
 104                 }
 105         } else {
 106                 declaration_t *parameter = scope->declarations;
 107                 for( ; parameter != NULL; parameter = parameter->next) {
 108                         if(first) {
 109                                 first = 0;
 110                         } else {
 111                                 fputs(", ", out);
 112                         }
 113                         print_type_ext(parameter->type, parameter->symbol,
 114                                        &parameter->scope);
 115                 }
 116         }
 117         if(type->variadic) {
 118                 if(first) {
 119                         first = 0;
 120                 } else {
 121                         fputs(", ", out);
 122                 }
 123                 fputs("...", out);
 124         }
 125         if(first && !type->unspecified_parameters) {
 126                 fputs("void", out);
 127         }
 128         fputc(')', out);
 129 }
 130
 131 static void print_pointer_type_pre(const pointer_type_t *type)
 132 {
 133         intern_print_type_pre(type->points_to, false);
 134         fputs("*", out);
 135         print_type_qualifiers(type->type.qualifiers);
 136 }
 137
 138 static void print_pointer_type_post(const pointer_type_t *type)
 139 {
 140         intern_print_type_post(type->points_to, false);
 141 }
 142
 143 static void print_array_type_pre(const array_type_t *type)
 144 {
 145         intern_print_type_pre(type->element_type, false);
 146 }
 147
 148 static void print_array_type_post(const array_type_t *type)
 149 {
 150         fputc('[', out);
 151         if(type->is_static) {
 152                 fputs("static ", out);
 153         }
 154         print_type_qualifiers(type->type.qualifiers);
 155         if(type->size != NULL) {
 156                 print_expression(type->size);
 157         }
 158         fputc(']', out);
 159         intern_print_type_post(type->element_type, false);
 160 }
 161
 162 static void print_bitfield_type_post(const bitfield_type_t *type)
 163 {
 164         fputs(" : ", out);
 165         print_expression(type->size);
 166         intern_print_type_post(type->base, false);
 167 }
 168
 169 void print_enum_definition(const declaration_t *declaration)
 170 {
 171         fputs("{\n", out);
 172
 173         change_indent(1);
 174
 175         declaration_t *entry = declaration->next;
 176         for( ; entry != NULL && entry->storage_class == STORAGE_CLASS_ENUM_ENTRY;
 177                entry = entry->next) {
 178
 179                 print_indent();
 180                 fprintf(out, "%s", entry->symbol->string);
 181                 if(entry->init.initializer != NULL) {
 182                         fprintf(out, " = ");
 183                         print_expression(entry->init.enum_value);
 184                 }
 185                 fprintf(out, ",\n");
 186         }
 187
 188         change_indent(-1);
 189         print_indent();
 190         fputs("}", out);
 191 }
 192
 193 static void print_type_enum(const enum_type_t *type)
 194 {
 195         print_type_qualifiers(type->type.qualifiers);
 196         fputs("enum ", out);
 197
 198         declaration_t *declaration = type->declaration;
 199         symbol_t      *symbol      = declaration->symbol;
 200         if(symbol != NULL) {
 201                 fputs(symbol->string, out);
 202         } else {
 203                 print_enum_definition(declaration);
 204         }
 205 }
 206
 207 void print_compound_definition(const declaration_t *declaration)
 208 {
 209         fputs("{\n", out);
 210         change_indent(1);
 211
 212         declaration_t *iter = declaration->scope.declarations;
 213         for( ; iter != NULL; iter = iter->next) {
 214                 print_indent();
 215                 print_declaration(iter);
 216                 fputc('\n', out);
 217         }
 218
 219         change_indent(-1);
 220         print_indent();
 221         fputs("}", out);
 222 }
 223
 224 static void print_compound_type(const compound_type_t *type)
 225 {
 226         print_type_qualifiers(type->type.qualifiers);
 227
 228         if(type->type.kind == TYPE_COMPOUND_STRUCT) {
 229                 fputs("struct ", out);
 230         } else {
 231                 assert(type->type.kind == TYPE_COMPOUND_UNION);
 232                 fputs("union ", out);
 233         }
 234
 235         declaration_t *declaration = type->declaration;
 236         symbol_t      *symbol      = declaration->symbol;
 237         if(symbol != NULL) {
 238                 fputs(symbol->string, out);
 239         } else {
 240                 print_compound_definition(declaration);
 241         }
 242 }
 243
 244 static void print_typedef_type_pre(const typedef_type_t *const type)
 245 {
 246         print_type_qualifiers(type->type.qualifiers);
 247         fputs(type->declaration->symbol->string, out);
 248 }
 249
 250 static void print_typeof_type_pre(const typeof_type_t *const type)
 251 {
 252         fputs("typeof(", out);
 253         if(type->expression != NULL) {
 254                 assert(type->typeof_type == NULL);
 255                 print_expression(type->expression);
 256         } else {
 257                 print_type(type->typeof_type);
 258         }
 259         fputc(')', out);
 260 }
 261
 262 static void intern_print_type_pre(const type_t *const type, const bool top)
 263 {
 264         switch(type->kind) {
 265         case TYPE_ERROR:
 266                 fputs("<error>", out);
 267         case TYPE_INVALID:
 268                 fputs("<invalid>", out);
 269                 return;
 270         case TYPE_ENUM:
 271                 print_type_enum(&type->enumt);
 272                 return;
 273         case TYPE_ATOMIC:
 274                 print_atomic_type(&type->atomic);
 275                 return;
 276         case TYPE_COMPOUND_STRUCT:
 277         case TYPE_COMPOUND_UNION:
 278                 print_compound_type(&type->compound);
 279                 return;
 280         case TYPE_BUILTIN:
 281                 fputs(type->builtin.symbol->string, out);
 282                 return;
 283         case TYPE_FUNCTION:
 284                 print_function_type_pre(&type->function, top);
 285                 return;
 286         case TYPE_POINTER:
 287                 print_pointer_type_pre(&type->pointer);
 288                 return;
 289         case TYPE_BITFIELD:
 290                 intern_print_type_pre(type->bitfield.base, top);
 291                 return;
 292         case TYPE_ARRAY:
 293                 print_array_type_pre(&type->array);
 294                 return;
 295         case TYPE_TYPEDEF:
 296                 print_typedef_type_pre(&type->typedeft);
 297                 return;
 298         case TYPE_TYPEOF:
 299                 print_typeof_type_pre(&type->typeoft);
 300                 return;
 301         }
 302         fputs("unknown", out);
 303 }
 304
 305 static void intern_print_type_post(const type_t *const type, const bool top)
 306 {
 307         switch(type->kind) {
 308         case TYPE_FUNCTION:
 309                 print_function_type_post(&type->function, NULL, top);
 310                 return;
 311         case TYPE_POINTER:
 312                 print_pointer_type_post(&type->pointer);
 313                 return;
 314         case TYPE_ARRAY:
 315                 print_array_type_post(&type->array);
 316                 return;
 317         case TYPE_BITFIELD:
 318                 print_bitfield_type_post(&type->bitfield);
 319                 return;
 320         case TYPE_ERROR:
 321         case TYPE_INVALID:
 322         case TYPE_ATOMIC:
 323         case TYPE_ENUM:
 324         case TYPE_COMPOUND_STRUCT:
 325         case TYPE_COMPOUND_UNION:
 326         case TYPE_BUILTIN:
 327         case TYPE_TYPEOF:
 328         case TYPE_TYPEDEF:
 329                 break;
 330         }
 331 }
 332
 333 void print_type(const type_t *const type)
 334 {
 335         print_type_ext(type, NULL, NULL);
 336 }
 337
 338 void print_type_ext(const type_t *const type, const symbol_t *symbol,
 339                     const scope_t *scope)
 340 {
 341         if(type == NULL) {
 342                 fputs("nil type", out);
 343                 return;
 344         }
 345
 346         intern_print_type_pre(type, true);
 347         if(symbol != NULL) {
 348                 fputc(' ', out);
 349                 fputs(symbol->string, out);
 350         }
 351         if(type->kind == TYPE_FUNCTION) {
 352                 print_function_type_post(&type->function, scope, true);
 353         } else {
 354                 intern_print_type_post(type, true);
 355         }
 356 }
 357
 358 static size_t get_type_size(type_t *type)
 359 {
 360         switch(type->kind) {
 361         case TYPE_ATOMIC:          return sizeof(atomic_type_t);
 362         case TYPE_COMPOUND_STRUCT:
 363         case TYPE_COMPOUND_UNION:  return sizeof(compound_type_t);
 364         case TYPE_ENUM:            return sizeof(enum_type_t);
 365         case TYPE_FUNCTION:        return sizeof(function_type_t);
 366         case TYPE_POINTER:         return sizeof(pointer_type_t);
 367         case TYPE_ARRAY:           return sizeof(array_type_t);
 368         case TYPE_BUILTIN:         return sizeof(builtin_type_t);
 369         case TYPE_TYPEDEF:         return sizeof(typedef_type_t);
 370         case TYPE_TYPEOF:          return sizeof(typeof_type_t);
 371         case TYPE_BITFIELD:        return sizeof(bitfield_type_t);
 372         case TYPE_ERROR:           panic("error type found");
 373         case TYPE_INVALID:         panic("invalid type found");
 374         }
 375         panic("unknown type found");
 376 }
 377
 378 /**
 379  * duplicates a type
 380  * note that this does not produce a deep copy!
 381  */
 382 type_t *duplicate_type(type_t *type)
 383 {
 384         size_t size = get_type_size(type);
 385
 386         type_t *copy = obstack_alloc(type_obst, size);
 387         memcpy(copy, type, size);
 388
 389         return copy;
 390 }
 391
 392 type_t *get_unqualified_type(type_t *type)
 393 {
 394         if(type->base.qualifiers == TYPE_QUALIFIER_NONE)
 395                 return type;
 396
 397         type_t *unqualified_type          = duplicate_type(type);
 398         unqualified_type->base.qualifiers = TYPE_QUALIFIER_NONE;
 399
 400         type_t *result = typehash_insert(unqualified_type);
 401         if(result != unqualified_type) {
 402                 obstack_free(type_obst, unqualified_type);
 403         }
 404
 405         return result;
 406 }
 407
 408 bool type_valid(const type_t *type)
 409 {
 410         return type->kind != TYPE_INVALID;
 411 }
 412
 413 bool is_type_integer(const type_t *type)
 414 {
 415         assert(!is_typeref(type));
 416
 417         if(type->kind == TYPE_ENUM)
 418                 return true;
 419
 420         if(type->kind != TYPE_ATOMIC)
 421                 return false;
 422
 423         switch(type->atomic.akind) {
 424         case ATOMIC_TYPE_BOOL:
 425         case ATOMIC_TYPE_CHAR:
 426         case ATOMIC_TYPE_SCHAR:
 427         case ATOMIC_TYPE_UCHAR:
 428         case ATOMIC_TYPE_SHORT:
 429         case ATOMIC_TYPE_USHORT:
 430         case ATOMIC_TYPE_INT:
 431         case ATOMIC_TYPE_UINT:
 432         case ATOMIC_TYPE_LONG:
 433         case ATOMIC_TYPE_ULONG:
 434         case ATOMIC_TYPE_LONGLONG:
 435         case ATOMIC_TYPE_ULONGLONG:
 436                 return true;
 437         default:
 438                 return false;
 439         }
 440 }
 441
 442 bool is_type_floating(const type_t *type)
 443 {
 444         assert(!is_typeref(type));
 445
 446         if(type->kind != TYPE_ATOMIC)
 447                 return false;
 448
 449         switch(type->atomic.akind) {
 450         case ATOMIC_TYPE_FLOAT:
 451         case ATOMIC_TYPE_DOUBLE:
 452         case ATOMIC_TYPE_LONG_DOUBLE:
 453 #ifdef PROVIDE_COMPLEX
 454         case ATOMIC_TYPE_FLOAT_COMPLEX:
 455         case ATOMIC_TYPE_DOUBLE_COMPLEX:
 456         case ATOMIC_TYPE_LONG_DOUBLE_COMPLEX:
 457         case ATOMIC_TYPE_FLOAT_IMAGINARY:
 458         case ATOMIC_TYPE_DOUBLE_IMAGINARY:
 459         case ATOMIC_TYPE_LONG_DOUBLE_IMAGINARY:
 460 #endif
 461                 return true;
 462         default:
 463                 return false;
 464         }
 465 }
 466
 467 bool is_type_signed(const type_t *type)
 468 {
 469         assert(!is_typeref(type));
 470
 471         /* enum types are int for now */
 472         if(type->kind == TYPE_ENUM)
 473                 return true;
 474
 475         if(type->kind != TYPE_ATOMIC)
 476                 return false;
 477
 478         switch(type->atomic.akind) {
 479         case ATOMIC_TYPE_CHAR:
 480         case ATOMIC_TYPE_SCHAR:
 481         case ATOMIC_TYPE_SHORT:
 482         case ATOMIC_TYPE_INT:
 483         case ATOMIC_TYPE_LONG:
 484         case ATOMIC_TYPE_LONGLONG:
 485         case ATOMIC_TYPE_FLOAT:
 486         case ATOMIC_TYPE_DOUBLE:
 487         case ATOMIC_TYPE_LONG_DOUBLE:
 488 #ifdef PROVIDE_COMPLEX
 489         case ATOMIC_TYPE_FLOAT_COMPLEX:
 490         case ATOMIC_TYPE_DOUBLE_COMPLEX:
 491         case ATOMIC_TYPE_LONG_DOUBLE_COMPLEX:
 492         case ATOMIC_TYPE_FLOAT_IMAGINARY:
 493         case ATOMIC_TYPE_DOUBLE_IMAGINARY:
 494         case ATOMIC_TYPE_LONG_DOUBLE_IMAGINARY:
 495 #endif
 496                 return true;
 497
 498         case ATOMIC_TYPE_BOOL:
 499         case ATOMIC_TYPE_UCHAR:
 500         case ATOMIC_TYPE_USHORT:
 501         case ATOMIC_TYPE_UINT:
 502         case ATOMIC_TYPE_ULONG:
 503         case ATOMIC_TYPE_ULONGLONG:
 504                 return false;
 505
 506         case ATOMIC_TYPE_VOID:
 507         case ATOMIC_TYPE_INVALID:
 508         case ATOMIC_TYPE_LAST:
 509                 return false;
 510         }
 511
 512         panic("invalid atomic type found");
 513         return false;
 514 }
 515
 516 bool is_type_arithmetic(const type_t *type)
 517 {
 518         assert(!is_typeref(type));
 519
 520         if(type->kind == TYPE_BITFIELD)
 521                 return true;
 522
 523         if(is_type_integer(type) || is_type_floating(type))
 524                 return true;
 525
 526         return false;
 527 }
 528
 529 bool is_type_scalar(const type_t *type)
 530 {
 531         assert(!is_typeref(type));
 532
 533         switch (type->kind) {
 534                 case TYPE_POINTER: return true;
 535                 case TYPE_BUILTIN: return is_type_scalar(type->builtin.real_type);
 536                 default:            break;
 537         }
 538
 539         return is_type_arithmetic(type);
 540 }
 541
 542 /**
 543  * Check if a given type is incomplete
 544  */
 545 bool is_type_incomplete(const type_t *type)
 546 {
 547         assert(!is_typeref(type));
 548
 549         switch(type->kind) {
 550         case TYPE_COMPOUND_STRUCT:
 551         case TYPE_COMPOUND_UNION: {
 552                 const compound_type_t *compound_type = &type->compound;
 553                 declaration_t         *declaration   = compound_type->declaration;
 554                 return !declaration->init.is_defined;
 555         }
 556         case TYPE_ENUM: {
 557                 const enum_type_t *enum_type   = &type->enumt;
 558                 declaration_t     *declaration = enum_type->declaration;
 559                 return !declaration->init.is_defined;
 560         }
 561         case TYPE_BITFIELD:
 562         case TYPE_FUNCTION:
 563                 return true;
 564
 565         case TYPE_ARRAY:
 566                 return type->array.size == NULL;
 567
 568         case TYPE_ATOMIC:
 569                 return type->atomic.akind == ATOMIC_TYPE_VOID;
 570
 571         case TYPE_POINTER:
 572         case TYPE_BUILTIN:
 573         case TYPE_ERROR:
 574                 return false;
 575
 576         case TYPE_TYPEDEF:
 577         case TYPE_TYPEOF:
 578                 panic("is_type_incomplete called without typerefs skipped");
 579         case TYPE_INVALID:
 580                 break;
 581         }
 582
 583         panic("invalid type found");
 584 }
 585
 586 static bool function_types_compatible(const function_type_t *func1,
 587                                       const function_type_t *func2)
 588 {
 589         const type_t* const ret1 = skip_typeref(func1->return_type);
 590         const type_t* const ret2 = skip_typeref(func2->return_type);
 591         if (!types_compatible(ret1, ret2))
 592                 return false;
 593
 594         /* can parameters be compared? */
 595         if(func1->unspecified_parameters || func2->unspecified_parameters)
 596                 return true;
 597
 598         if(func1->variadic != func2->variadic)
 599                 return false;
 600
 601         /* TODO: handling of unspecified parameters not correct yet */
 602
 603         /* all argument types must be compatible */
 604         function_parameter_t *parameter1 = func1->parameters;
 605         function_parameter_t *parameter2 = func2->parameters;
 606         for( ; parameter1 != NULL && parameter2 != NULL;
 607                         parameter1 = parameter1->next, parameter2 = parameter2->next) {
 608                 type_t *parameter1_type = skip_typeref(parameter1->type);
 609                 type_t *parameter2_type = skip_typeref(parameter2->type);
 610
 611                 parameter1_type = get_unqualified_type(parameter1_type);
 612                 parameter2_type = get_unqualified_type(parameter2_type);
 613
 614                 if(!types_compatible(parameter1_type, parameter2_type))
 615                         return false;
 616         }
 617         /* same number of arguments? */
 618         if(parameter1 != NULL || parameter2 != NULL)
 619                 return false;
 620
 621         return true;
 622 }
 623
 624 static bool array_types_compatible(const array_type_t *array1,
 625                                    const array_type_t *array2)
 626 {
 627         type_t *element_type1 = skip_typeref(array1->element_type);
 628         type_t *element_type2 = skip_typeref(array2->element_type);
 629         if(!types_compatible(element_type1, element_type2))
 630                 return false;
 631
 632         if(array1->size != NULL && array2->size != NULL) {
 633                 /* TODO: check if size expression evaluate to the same value
 634                  * if they are constant */
 635         }
 636
 637         return true;
 638 }
 639
 640 bool types_compatible(const type_t *type1, const type_t *type2)
 641 {
 642         assert(!is_typeref(type1));
 643         assert(!is_typeref(type2));
 644
 645         /* shortcut: the same type is always compatible */
 646         if(type1 == type2)
 647                 return true;
 648
 649         if(type1->base.qualifiers != type2->base.qualifiers)
 650                 return false;
 651         if(type1->kind != type2->kind)
 652                 return false;
 653
 654         switch(type1->kind) {
 655         case TYPE_FUNCTION:
 656                 return function_types_compatible(&type1->function, &type2->function);
 657         case TYPE_ATOMIC:
 658                 return type1->atomic.akind == type2->atomic.akind;
 659         case TYPE_ARRAY:
 660                 return array_types_compatible(&type1->array, &type2->array);
 661
 662         case TYPE_POINTER: {
 663                 const type_t *const to1 = skip_typeref(type1->pointer.points_to);
 664                 const type_t *const to2 = skip_typeref(type2->pointer.points_to);
 665                 return types_compatible(to1, to2);
 666         }
 667
 668         case TYPE_COMPOUND_STRUCT:
 669         case TYPE_COMPOUND_UNION:
 670         case TYPE_ENUM:
 671         case TYPE_BUILTIN:
 672                 /* TODO: not implemented */
 673                 break;
 674
 675         case TYPE_BITFIELD:
 676                 /* not sure if this makes sense or is even needed, implement it if you
 677                  * really need it! */
 678                 panic("type compatibility check for bitfield type");
 679
 680         case TYPE_ERROR:
 681                 /* Hmm, the error type should be compatible to all other types */
 682                 return true;
 683         case TYPE_INVALID:
 684                 panic("invalid type found in compatible types");
 685         case TYPE_TYPEDEF:
 686         case TYPE_TYPEOF:
 687                 panic("typerefs not skipped in compatible types?!?");
 688         }
 689
 690         /* TODO: incomplete */
 691         return false;
 692 }
 693
 694 bool pointers_compatible(const type_t *type1, const type_t *type2)
 695 {
 696         assert(!is_typeref(type1));
 697         assert(!is_typeref(type2));
 698
 699         assert(type1->kind == TYPE_POINTER);
 700         assert(type2->kind == TYPE_POINTER);
 701         /* TODO */
 702         return true;
 703 }
 704
 705 /**
 706  * Skip all typerefs and return the underlying type.
 707  */
 708 type_t *skip_typeref(type_t *type)
 709 {
 710         unsigned qualifiers = TYPE_QUALIFIER_NONE;
 711
 712         while(true) {
 713                 switch(type->kind) {
 714                 case TYPE_ERROR:
 715                         return type;
 716                 case TYPE_TYPEDEF: {
 717                         qualifiers |= type->base.qualifiers;
 718                         const typedef_type_t *typedef_type = &type->typedeft;
 719                         if(typedef_type->resolved_type != NULL) {
 720                                 type = typedef_type->resolved_type;
 721                                 break;
 722                         }
 723                         type = typedef_type->declaration->type;
 724                         continue;
 725                 }
 726                 case TYPE_TYPEOF: {
 727                         const typeof_type_t *typeof_type = &type->typeoft;
 728                         if(typeof_type->typeof_type != NULL) {
 729                                 type = typeof_type->typeof_type;
 730                         } else {
 731                                 type = typeof_type->expression->base.datatype;
 732                         }
 733                         continue;
 734                 }
 735                 default:
 736                         break;
 737                 }
 738                 break;
 739         }
 740
 741         if (qualifiers != TYPE_QUALIFIER_NONE) {
 742                 type_t *const copy     = duplicate_type(type);
 743                 copy->base.qualifiers |= qualifiers;
 744
 745                 type = typehash_insert(copy);
 746                 if (type != copy) {
 747                         obstack_free(type_obst, copy);
 748                 }
 749         }
 750
 751         return type;
 752 }
 753
 754
 755
 756 static type_t *identify_new_type(type_t *type)
 757 {
 758         type_t *result = typehash_insert(type);
 759         if(result != type) {
 760                 obstack_free(type_obst, type);
 761         }
 762         return result;
 763 }
 764
 765 type_t *make_atomic_type(atomic_type_kind_t atype, type_qualifiers_t qualifiers)
 766 {
 767         type_t *type = obstack_alloc(type_obst, sizeof(atomic_type_t));
 768         memset(type, 0, sizeof(atomic_type_t));
 769
 770         type->kind            = TYPE_ATOMIC;
 771         type->base.qualifiers = qualifiers;
 772         type->atomic.akind    = atype;
 773
 774         return identify_new_type(type);
 775 }
 776
 777 type_t *make_pointer_type(type_t *points_to, type_qualifiers_t qualifiers)
 778 {
 779         type_t *type = obstack_alloc(type_obst, sizeof(pointer_type_t));
 780         memset(type, 0, sizeof(pointer_type_t));
 781
 782         type->kind              = TYPE_POINTER;
 783         type->base.qualifiers   = qualifiers;
 784         type->pointer.points_to = points_to;
 785
 786         return identify_new_type(type);
 787 }
 788
 789 static __attribute__((unused))
 790 void dbg_type(type_t *type)
 791 {
 792         FILE *old_out = out;
 793         out = stderr;
 794         print_type(type);
 795         puts("\n");
 796         fflush(stderr);
 797         out = old_out;
 798 }