nsz Git - cparser/blob - attribute.c

   1 /*
   2  * This file is part of cparser.
   3  * Copyright (C) 2007-2009 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 "adt/strutil.h"
  24 #include "diagnostic.h"
  25 #include "warning.h"
  26 #include "attribute_t.h"
  27 #include "symbol_t.h"
  28 #include "adt/error.h"
  29 #include "type_t.h"
  30
  31 static const char *const attribute_names[ATTRIBUTE_LAST+1] = {
  32         [ATTRIBUTE_GNU_ALIAS]                  = "alias",
  33         [ATTRIBUTE_GNU_ALIGNED]                = "aligned",
  34         [ATTRIBUTE_GNU_ALWAYS_INLINE]          = "always_inline",
  35         [ATTRIBUTE_GNU_CDECL]                  = "cdecl",
  36         [ATTRIBUTE_GNU_COMMON]                 = "common",
  37         [ATTRIBUTE_GNU_CONST]                  = "const",
  38         [ATTRIBUTE_GNU_CONSTRUCTOR]            = "constructor",
  39         [ATTRIBUTE_GNU_DEPRECATED]             = "deprecated",
  40         [ATTRIBUTE_GNU_DESTRUCTOR]             = "destructor",
  41         [ATTRIBUTE_GNU_DLLEXPORT]              = "dllexport",
  42         [ATTRIBUTE_GNU_DLLIMPORT]              = "dllimport",
  43         [ATTRIBUTE_GNU_EIGTHBIT_DATA]          = "eightbit_data",
  44         [ATTRIBUTE_GNU_EXTERNALLY_VISIBLE]     = "externally_visible",
  45         [ATTRIBUTE_GNU_FAR]                    = "far",
  46         [ATTRIBUTE_GNU_FASTCALL]               = "fastcall",
  47         [ATTRIBUTE_GNU_FLATTEN]                = "flatten",
  48         [ATTRIBUTE_GNU_FORMAT_ARG]             = "format_arg",
  49         [ATTRIBUTE_GNU_FORMAT]                 = "format",
  50         [ATTRIBUTE_GNU_FUNCTION_VECTOR]        = "function_vector",
  51         [ATTRIBUTE_GNU_GCC_STRUCT]             = "gcc_struct",
  52         [ATTRIBUTE_GNU_INTERRUPT_HANDLER]      = "interrupt_handler",
  53         [ATTRIBUTE_GNU_INTERRUPT]              = "interrupt",
  54         [ATTRIBUTE_GNU_LEAF]                   = "leaf",
  55         [ATTRIBUTE_GNU_LONGCALL]               = "longcall",
  56         [ATTRIBUTE_GNU_LONG_CALL]              = "long_call",
  57         [ATTRIBUTE_GNU_MALLOC]                 = "malloc",
  58         [ATTRIBUTE_GNU_MAY_ALIAS]              = "may_alias",
  59         [ATTRIBUTE_GNU_MODEL]                  = "model",
  60         [ATTRIBUTE_GNU_MODE]                   = "mode",
  61         [ATTRIBUTE_GNU_MS_STRUCT]              = "ms_struct",
  62         [ATTRIBUTE_GNU_NAKED]                  = "naked",
  63         [ATTRIBUTE_GNU_NEAR]                   = "near",
  64         [ATTRIBUTE_GNU_NESTING]                = "nesting",
  65         [ATTRIBUTE_GNU_NMI_HANDLER]            = "nmi_handler",
  66         [ATTRIBUTE_GNU_NOCOMMON]               = "nocommon",
  67         [ATTRIBUTE_GNU_NOINLINE]               = "noinline",
  68         [ATTRIBUTE_GNU_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
  69         [ATTRIBUTE_GNU_NONNULL]                = "nonnull",
  70         [ATTRIBUTE_GNU_NORETURN]               = "noreturn",
  71         [ATTRIBUTE_GNU_NOTHROW]                = "nothrow",
  72         [ATTRIBUTE_GNU_NOTSHARED]              = "notshared",
  73         [ATTRIBUTE_GNU_PACKED]                 = "packed",
  74         [ATTRIBUTE_GNU_PURE]                   = "pure",
  75         [ATTRIBUTE_GNU_REGPARM]                = "regparm",
  76         [ATTRIBUTE_GNU_RETURNS_TWICE]          = "returns_twice",
  77         [ATTRIBUTE_GNU_SAVEALL]                = "saveall",
  78         [ATTRIBUTE_GNU_SECTION]                = "section",
  79         [ATTRIBUTE_GNU_SENTINEL]               = "sentinel",
  80         [ATTRIBUTE_GNU_SHARED]                 = "shared",
  81         [ATTRIBUTE_GNU_SHORTCALL]              = "shortcall",
  82         [ATTRIBUTE_GNU_SHORT_CALL]             = "short_call",
  83         [ATTRIBUTE_GNU_SIGNAL]                 = "signal",
  84         [ATTRIBUTE_GNU_SP_SWITCH]              = "sp_switch",
  85         [ATTRIBUTE_GNU_SSEREGPARM]             = "sseregparm",
  86         [ATTRIBUTE_GNU_STDCALL]                = "stdcall",
  87         [ATTRIBUTE_GNU_TINY_DATA]              = "tiny_data",
  88         [ATTRIBUTE_GNU_TLS_MODEL]              = "tls_model",
  89         [ATTRIBUTE_GNU_TRANSPARENT_UNION]      = "transparent_union",
  90         [ATTRIBUTE_GNU_TRAP_EXIT]              = "trap_exit",
  91         [ATTRIBUTE_GNU_UNUSED]                 = "unused",
  92         [ATTRIBUTE_GNU_USED]                   = "used",
  93         [ATTRIBUTE_GNU_VISIBILITY]             = "visibility",
  94         [ATTRIBUTE_GNU_VOLATILE]               = "volatile",
  95         [ATTRIBUTE_GNU_WARN_UNUSED_RESULT]     = "warn_unused_result",
  96         [ATTRIBUTE_GNU_WEAKREF]                = "weakref",
  97         [ATTRIBUTE_GNU_WEAK]                   = "weak",
  98
  99         [ATTRIBUTE_MS_ALIGN]                   = "align",
 100         [ATTRIBUTE_MS_ALLOCATE]                = "allocate",
 101         [ATTRIBUTE_MS_DEPRECATED]              = "deprecated",
 102         [ATTRIBUTE_MS_DLLEXPORT]               = "dllexport",
 103         [ATTRIBUTE_MS_DLLIMPORT]               = "dllimport",
 104         [ATTRIBUTE_MS_NAKED]                   = "naked",
 105         [ATTRIBUTE_MS_NOALIAS]                 = "noalias",
 106         [ATTRIBUTE_MS_NOINLINE]                = "noinline",
 107         [ATTRIBUTE_MS_NORETURN]                = "noreturn",
 108         [ATTRIBUTE_MS_NOTHROW]                 = "nothrow",
 109         [ATTRIBUTE_MS_NOVTABLE]                = "novtable",
 110         [ATTRIBUTE_MS_PROPERTY]                = "property",
 111         [ATTRIBUTE_MS_RESTRICT]                = "restrict",
 112         [ATTRIBUTE_MS_RETURNS_TWICE]           = "returns_twice",
 113         [ATTRIBUTE_MS_SELECTANY]               = "selectany",
 114         [ATTRIBUTE_MS_THREAD]                  = "thread",
 115         [ATTRIBUTE_MS_UUID]                    = "uuid",
 116 };
 117
 118 const char *get_attribute_name(attribute_kind_t kind)
 119 {
 120         assert(kind <= ATTRIBUTE_LAST);
 121         return attribute_names[kind];
 122 }
 123
 124 type_t *handle_attribute_mode(const attribute_t *attribute, type_t *orig_type)
 125 {
 126         type_t *type = skip_typeref(orig_type);
 127
 128         /* at least: byte, word, pointer, list of machine modes
 129          * __XXX___ is interpreted as XXX */
 130
 131         /* This isn't really correct, the backend should provide a list of machine
 132          * specific modes (according to gcc philosophy that is...) */
 133         attribute_argument_t *arg = attribute->a.arguments;
 134         if (arg == NULL) {
 135                 errorf(&attribute->source_position,
 136                        "__attribute__((mode(X))) misses argument");
 137                 return orig_type;
 138         }
 139
 140         const char         *symbol_str = arg->v.symbol->string;
 141         bool                sign       = is_type_signed(type);
 142         atomic_type_kind_t  akind;
 143         if (streq_underscore("QI",   symbol_str) ||
 144             streq_underscore("byte", symbol_str)) {
 145                 akind = sign ? ATOMIC_TYPE_CHAR : ATOMIC_TYPE_UCHAR;
 146         } else if (streq_underscore("HI", symbol_str)) {
 147                 akind = sign ? ATOMIC_TYPE_SHORT : ATOMIC_TYPE_USHORT;
 148         } else if (streq_underscore("SI",      symbol_str)
 149                 || streq_underscore("word",    symbol_str)
 150                 || streq_underscore("pointer", symbol_str)) {
 151                 akind = sign ? ATOMIC_TYPE_INT : ATOMIC_TYPE_UINT;
 152         } else if (streq_underscore("DI", symbol_str)) {
 153                 akind = sign ? ATOMIC_TYPE_LONGLONG : ATOMIC_TYPE_ULONGLONG;
 154         } else {
 155                 source_position_t const *const pos = &attribute->source_position;
 156                 warningf(WARN_OTHER, pos, "ignoring unknown mode '%s'", symbol_str);
 157                 return orig_type;
 158         }
 159
 160         if (type->kind == TYPE_ATOMIC || type->kind == TYPE_ENUM) {
 161                 type_t *copy       = duplicate_type(type);
 162                 copy->atomic.akind = akind;
 163                 return identify_new_type(copy);
 164         } else if (is_type_pointer(type)) {
 165                 source_position_t const *const pos = &attribute->source_position;
 166                 warningf(WARN_OTHER, pos, "__attribute__((mode)) on pointers not implemented yet (ignored)");
 167                 return type;
 168         }
 169
 170         errorf(&attribute->source_position,
 171                "__attribute__((mode)) only allowed on integer, enum or pointer type");
 172         return orig_type;
 173 }
 174
 175 static inline bool is_po2(unsigned x)
 176 {
 177         return (x & (x-1)) == 0;
 178 }
 179
 180 static void handle_attribute_aligned(const attribute_t *attribute,
 181                                      entity_t *entity)
 182 {
 183         int alignment = 32; /* TODO: fill in maximum useful alignment for
 184                                                    target machine */
 185         if (attribute->a.arguments) {
 186                 attribute_argument_t *argument = attribute->a.arguments;
 187                 alignment = fold_constant_to_int(argument->v.expression);
 188         }
 189
 190         if (!is_po2(alignment)) {
 191                 errorf(&attribute->source_position, "alignment must be a power of 2 but is %d", alignment);
 192                 return;
 193         }
 194         if (alignment <= 0) {
 195                 errorf(&attribute->source_position, "alignment must be bigger than 0 but is %d", alignment);
 196                 return;
 197         }
 198
 199         switch (entity->kind) {
 200         case DECLARATION_KIND_CASES:
 201                 entity->declaration.alignment = alignment;
 202         case ENTITY_TYPEDEF:
 203                 entity->typedefe.alignment = alignment;
 204                 break;
 205         case ENTITY_STRUCT:
 206         case ENTITY_UNION:
 207                 if (alignment > (int)entity->compound.alignment) {
 208                         entity->compound.alignment = alignment;
 209                 }
 210                 break;
 211
 212         default:
 213                 warningf(WARN_OTHER, &attribute->source_position, "alignment attribute specification on '%N' ignored", entity);
 214                 break;
 215         }
 216 }
 217
 218 static const char *get_argument_string(const attribute_argument_t *argument)
 219 {
 220         if (argument == NULL)
 221                 return NULL;
 222         if (argument->kind != ATTRIBUTE_ARGUMENT_EXPRESSION)
 223                 return NULL;
 224         expression_t *expression = argument->v.expression;
 225         if (expression->kind != EXPR_STRING_LITERAL)
 226                 return NULL;
 227         return expression->string_literal.value.begin;
 228 }
 229
 230 static void handle_attribute_visibility(const attribute_t *attribute,
 231                                         entity_t *entity)
 232 {
 233         /* This isn't really correct, the backend should provide a list of machine
 234          * specific modes (according to gcc philosophy that is...) */
 235         attribute_argument_t *arg = attribute->a.arguments;
 236         if (arg == NULL) {
 237                 errorf(&attribute->source_position,
 238                        "__attribute__((visibility(X))) misses argument");
 239                 return;
 240         }
 241         const char *string = get_argument_string(arg);
 242         if (string == NULL) {
 243                 errorf(&attribute->source_position,
 244                        "__attribute__((visibility(X))) argument is not a string");
 245                 return;
 246         }
 247         elf_visibility_tag_t visibility = get_elf_visibility_from_string(string);
 248         if (visibility == ELF_VISIBILITY_ERROR) {
 249                 errorf(&attribute->source_position,
 250                        "unknown visibility type '%s'", string);
 251                 return;
 252         }
 253
 254         switch (entity->kind) {
 255         case ENTITY_VARIABLE:
 256                 entity->variable.elf_visibility = visibility;
 257                 break;
 258         case ENTITY_FUNCTION:
 259                 entity->function.elf_visibility = visibility;
 260                 break;
 261
 262         default:
 263                 warningf(WARN_OTHER, &attribute->source_position, "visibility attribute specification on '%N' ignored", entity);
 264                 break;
 265         }
 266 }
 267
 268 static void warn_arguments(const attribute_t *attribute)
 269 {
 270         if (attribute->a.arguments == NULL)
 271                 return;
 272
 273         source_position_t const *const pos  = &attribute->source_position;
 274         char              const *const what = get_attribute_name(attribute->kind);
 275         warningf(WARN_OTHER, pos, "attribute '%s' needs no arguments", what);
 276 }
 277
 278 static void handle_attribute_packed_e(const attribute_t *attribute,
 279                                       entity_t *entity)
 280 {
 281 #if 0
 282         if (entity->kind != ENTITY_STRUCT) {
 283                 warningf(WARN_OTHER, &attribute->source_position, "packed attribute on '%N' ignored", entity);
 284                 return;
 285         }
 286 #endif
 287
 288         warn_arguments(attribute);
 289         entity->compound.packed = true;
 290 }
 291
 292 static void handle_attribute_packed(const attribute_t *attribute, type_t *type)
 293 {
 294         if (type->kind != TYPE_COMPOUND_STRUCT) {
 295                 source_position_t const *const pos  = &attribute->source_position;
 296                 warningf(WARN_OTHER, pos, "packed attribute on type '%T' ignored", type);
 297                 return;
 298         }
 299
 300         handle_attribute_packed_e(attribute, (entity_t*) type->compound.compound);
 301 }
 302
 303 static void handle_attribute_asm(const attribute_t *attribute,
 304                                       entity_t *entity)
 305 {
 306         attribute_argument_t *argument = attribute->a.arguments;
 307         assert (argument->kind == ATTRIBUTE_ARGUMENT_EXPRESSION);
 308         expression_t *expression = argument->v.expression;
 309         if (expression->kind != EXPR_STRING_LITERAL)
 310                 errorf(&attribute->source_position,
 311                        "Invalid asm attribute expression");
 312         symbol_t *sym = symbol_table_insert(expression->string_literal.value.begin);
 313         entity->function.actual_name = sym;
 314         assert(argument->next == NULL);
 315         return;
 316 }
 317
 318 void handle_entity_attributes(const attribute_t *attributes, entity_t *entity)
 319 {
 320         if (entity->kind == ENTITY_TYPEDEF) {
 321                 type_t *type = entity->typedefe.type;
 322                 type = handle_type_attributes(attributes, type);
 323                 entity->typedefe.type = type;
 324         } else if (is_declaration(entity)) {
 325                 type_t *type = entity->declaration.type;
 326                 type = handle_type_attributes(attributes, type);
 327                 entity->declaration.type = type;
 328         }
 329
 330         decl_modifiers_t modifiers = 0;
 331         const attribute_t *attribute = attributes;
 332         for ( ; attribute != NULL; attribute = attribute->next) {
 333                 switch(attribute->kind) {
 334                 case ATTRIBUTE_GNU_CONST:         modifiers |= DM_CONST; break;
 335                 case ATTRIBUTE_GNU_DEPRECATED:    modifiers |= DM_DEPRECATED; break;
 336                 case ATTRIBUTE_GNU_NOINLINE:      modifiers |= DM_NOINLINE; break;
 337                 case ATTRIBUTE_GNU_NAKED:         modifiers |= DM_NAKED; break;
 338                 case ATTRIBUTE_GNU_PURE:          modifiers |= DM_PURE; break;
 339                 case ATTRIBUTE_GNU_ALWAYS_INLINE: modifiers |= DM_FORCEINLINE; break;
 340                 case ATTRIBUTE_GNU_CONSTRUCTOR:   modifiers |= DM_CONSTRUCTOR; break;
 341                 case ATTRIBUTE_GNU_DESTRUCTOR:    modifiers |= DM_DESTRUCTOR; break;
 342                 case ATTRIBUTE_GNU_TRANSPARENT_UNION:
 343                                                                                   modifiers |= DM_TRANSPARENT_UNION;
 344                                                                                   break;
 345                 case ATTRIBUTE_GNU_USED:          modifiers |= DM_USED; break;
 346                 case ATTRIBUTE_GNU_UNUSED:        modifiers |= DM_UNUSED; break;
 347                 case ATTRIBUTE_GNU_DLLIMPORT:     modifiers |= DM_DLLIMPORT; break;
 348                 case ATTRIBUTE_GNU_DLLEXPORT:     modifiers |= DM_DLLEXPORT; break;
 349                 case ATTRIBUTE_GNU_WEAK:          modifiers |= DM_WEAK; break;
 350                 case ATTRIBUTE_GNU_LEAF:          modifiers |= DM_LEAF; break;
 351
 352                 case ATTRIBUTE_MS_DLLIMPORT:     modifiers |= DM_DLLIMPORT; break;
 353                 case ATTRIBUTE_MS_DLLEXPORT:     modifiers |= DM_DLLEXPORT; break;
 354                 case ATTRIBUTE_MS_NAKED:         modifiers |= DM_NAKED; break;
 355                 case ATTRIBUTE_MS_NOINLINE:      modifiers |= DM_NOINLINE; break;
 356                 case ATTRIBUTE_MS_THREAD:        modifiers |= DM_THREAD; break;
 357                 case ATTRIBUTE_MS_DEPRECATED:    modifiers |= DM_DEPRECATED; break;
 358                 case ATTRIBUTE_MS_RESTRICT:      modifiers |= DM_RESTRICT; break;
 359                 case ATTRIBUTE_MS_NOALIAS:       modifiers |= DM_NOALIAS; break;
 360
 361                 case ATTRIBUTE_GNU_PACKED:
 362                         handle_attribute_packed_e(attribute, entity);
 363                         break;
 364
 365                 case ATTRIBUTE_GNU_ASM:
 366                         handle_attribute_asm(attribute, entity);
 367                         break;
 368
 369                 case ATTRIBUTE_GNU_VISIBILITY:
 370                         handle_attribute_visibility(attribute, entity);
 371                         break;
 372
 373                 case ATTRIBUTE_MS_ALIGN:
 374                 case ATTRIBUTE_GNU_ALIGNED:
 375                         handle_attribute_aligned(attribute, entity);
 376                         break;
 377                 default: break;
 378                 }
 379         }
 380
 381         if (modifiers != 0) {
 382                 switch(entity->kind) {
 383                 case ENTITY_TYPEDEF:
 384                         entity->typedefe.modifiers |= modifiers;
 385                         break;
 386                 case ENTITY_UNION:
 387                 case ENTITY_STRUCT:
 388                         entity->compound.modifiers |= modifiers;
 389                         break;
 390                 case ENTITY_COMPOUND_MEMBER:
 391                 case ENTITY_VARIABLE:
 392                 case ENTITY_FUNCTION:
 393                         entity->declaration.modifiers |= modifiers;
 394                         break;
 395                 default:
 396                         /* TODO: warning */
 397                         break;
 398                 }
 399         }
 400 }
 401
 402 static type_t *change_calling_convention(type_t *type, cc_kind_t cconv)
 403 {
 404         if (is_typeref(type) || !is_type_function(type)) {
 405                 return type;
 406         }
 407
 408         if (type->function.calling_convention == cconv)
 409                 return type;
 410
 411         type_t* new_type = duplicate_type(type);
 412         new_type->function.calling_convention = cconv;
 413         return identify_new_type(new_type);
 414 }
 415
 416 static type_t *add_modifiers(type_t *type, decl_modifiers_t modifiers)
 417 {
 418         if (is_typeref(type) || !is_type_function(type)) {
 419                 return type;
 420         }
 421
 422         if ((type->function.modifiers & modifiers) == modifiers)
 423                 return type;
 424
 425         type_t* new_type = duplicate_type(type);
 426         new_type->function.modifiers |= modifiers;
 427         return identify_new_type(new_type);
 428 }
 429
 430 type_t *handle_type_attributes(const attribute_t *attributes, type_t *type)
 431 {
 432         const attribute_t *attribute = attributes;
 433         for ( ; attribute != NULL; attribute = attribute->next) {
 434                 switch(attribute->kind) {
 435                 case ATTRIBUTE_GNU_PACKED:
 436                         handle_attribute_packed(attribute, type);
 437                         break;
 438                 case ATTRIBUTE_GNU_CDECL:
 439                 case ATTRIBUTE_MS_CDECL:
 440                         type = change_calling_convention(type, CC_CDECL);
 441                         break;
 442                 case ATTRIBUTE_MS_STDCALL:
 443                 case ATTRIBUTE_GNU_STDCALL:
 444                         type = change_calling_convention(type, CC_STDCALL);
 445                         break;
 446                 case ATTRIBUTE_MS_FASTCALL:
 447                 case ATTRIBUTE_GNU_FASTCALL:
 448                         type = change_calling_convention(type, CC_FASTCALL);
 449                         break;
 450                 case ATTRIBUTE_MS_THISCALL:
 451                         type = change_calling_convention(type, CC_THISCALL);
 452                         break;
 453                 case ATTRIBUTE_GNU_RETURNS_TWICE:
 454                 case ATTRIBUTE_MS_RETURNS_TWICE:
 455                         type = add_modifiers(type, DM_RETURNS_TWICE);
 456                         break;
 457                 case ATTRIBUTE_GNU_NORETURN:
 458                 case ATTRIBUTE_MS_NORETURN:
 459                         type = add_modifiers(type, DM_NORETURN);
 460                         break;
 461                 case ATTRIBUTE_GNU_MALLOC:
 462                 case ATTRIBUTE_MS_ALLOCATE:
 463                         type = add_modifiers(type, DM_MALLOC);
 464                         break;
 465                 case ATTRIBUTE_GNU_NOTHROW:
 466                 case ATTRIBUTE_MS_NOTHROW:
 467                         type = add_modifiers(type, DM_NOTHROW);
 468                         break;
 469                 case ATTRIBUTE_GNU_MODE:
 470                         type = handle_attribute_mode(attribute, type);
 471                         break;
 472                 default:
 473                         break;
 474                 }
 475         }
 476
 477         return type;
 478 }
 479
 480 const char *get_deprecated_string(const attribute_t *attribute)
 481 {
 482         for ( ; attribute != NULL; attribute = attribute->next) {
 483                 if (attribute->kind != ATTRIBUTE_MS_DEPRECATED)
 484                         continue;
 485
 486                 attribute_argument_t *argument = attribute->a.arguments;
 487                 return get_argument_string(argument);
 488         }
 489         return NULL;
 490 }
 491
 492 static bool property_attribute_equal(const attribute_property_argument_t *prop1,
 493                                      const attribute_property_argument_t *prop2)
 494 {
 495         return prop1->put_symbol == prop2->put_symbol
 496                 && prop1->get_symbol == prop2->get_symbol;
 497 }
 498
 499 static bool attribute_argument_equal(const attribute_argument_t *arg1,
 500                                      const attribute_argument_t *arg2)
 501 {
 502         if (arg1->kind != arg2->kind)
 503                 return false;
 504
 505         switch (arg1->kind) {
 506         case ATTRIBUTE_ARGUMENT_SYMBOL:
 507                 return arg1->v.symbol == arg2->v.symbol;
 508         case ATTRIBUTE_ARGUMENT_EXPRESSION:
 509                 /* TODO */
 510                 return false;
 511         }
 512         panic("unknown argument type");
 513 }
 514
 515 static bool attribute_arguments_equal(const attribute_argument_t *args1,
 516                                       const attribute_argument_t *args2)
 517 {
 518         for ( ; args1 != NULL && args2 != NULL;
 519              args1 = args1->next, args2 = args2->next) {
 520                 if (!attribute_argument_equal(args1, args2))
 521                         return false;
 522         }
 523         /* both should be NULL now */
 524         return args1 == args2;
 525 }
 526
 527 bool attributes_equal(const attribute_t *attr1, const attribute_t *attr2)
 528 {
 529         if (attr1->kind != attr2->kind)
 530                 return false;
 531
 532         switch (attr1->kind) {
 533         case ATTRIBUTE_MS_PROPERTY:
 534                 return property_attribute_equal(attr1->a.property, attr2->a.property);
 535         default:
 536                 return attribute_arguments_equal(attr1->a.arguments,
 537                                                  attr2->a.arguments);
 538         }
 539 }