1 //===--------------------- SemaLookup.cpp - Name Lookup ------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file implements name lookup for C, C++, Objective-C, and 11 // Objective-C++. 12 // 13 //===----------------------------------------------------------------------===// 14 #include "clang/Sema/Sema.h" 15 #include "clang/Sema/SemaInternal.h" 16 #include "clang/Sema/Lookup.h" 17 #include "clang/Sema/Overload.h" 18 #include "clang/Sema/DeclSpec.h" 19 #include "clang/Sema/Scope.h" 20 #include "clang/Sema/ScopeInfo.h" 21 #include "clang/Sema/TemplateDeduction.h" 22 #include "clang/Sema/ExternalSemaSource.h" 23 #include "clang/Sema/TypoCorrection.h" 24 #include "clang/AST/ASTContext.h" 25 #include "clang/AST/CXXInheritance.h" 26 #include "clang/AST/Decl.h" 27 #include "clang/AST/DeclCXX.h" 28 #include "clang/AST/DeclLookups.h" 29 #include "clang/AST/DeclObjC.h" 30 #include "clang/AST/DeclTemplate.h" 31 #include "clang/AST/Expr.h" 32 #include "clang/AST/ExprCXX.h" 33 #include "clang/Basic/Builtins.h" 34 #include "clang/Basic/LangOptions.h" 35 #include "llvm/ADT/SetVector.h" 36 #include "llvm/ADT/STLExtras.h" 37 #include "llvm/ADT/SmallPtrSet.h" 38 #include "llvm/ADT/StringMap.h" 39 #include "llvm/ADT/TinyPtrVector.h" 40 #include "llvm/ADT/edit_distance.h" 41 #include "llvm/Support/ErrorHandling.h" 42 #include <algorithm> 43 #include <iterator> 44 #include <limits> 45 #include <list> 46 #include <map> 47 #include <set> 48 #include <utility> 49 #include <vector> 50 51 using namespace clang; 52 using namespace sema; 53 54 namespace { 55 class UnqualUsingEntry { 56 const DeclContext *Nominated; 57 const DeclContext *CommonAncestor; 58 59 public: 60 UnqualUsingEntry(const DeclContext *Nominated, 61 const DeclContext *CommonAncestor) 62 : Nominated(Nominated), CommonAncestor(CommonAncestor) { 63 } 64 65 const DeclContext *getCommonAncestor() const { 66 return CommonAncestor; 67 } 68 69 const DeclContext *getNominatedNamespace() const { 70 return Nominated; 71 } 72 73 // Sort by the pointer value of the common ancestor. 74 struct Comparator { 75 bool operator()(const UnqualUsingEntry &L, const UnqualUsingEntry &R) { 76 return L.getCommonAncestor() < R.getCommonAncestor(); 77 } 78 79 bool operator()(const UnqualUsingEntry &E, const DeclContext *DC) { 80 return E.getCommonAncestor() < DC; 81 } 82 83 bool operator()(const DeclContext *DC, const UnqualUsingEntry &E) { 84 return DC < E.getCommonAncestor(); 85 } 86 }; 87 }; 88 89 /// A collection of using directives, as used by C++ unqualified 90 /// lookup. 91 class UnqualUsingDirectiveSet { 92 typedef SmallVector<UnqualUsingEntry, 8> ListTy; 93 94 ListTy list; 95 llvm::SmallPtrSet<DeclContext*, 8> visited; 96 97 public: 98 UnqualUsingDirectiveSet() {} 99 100 void visitScopeChain(Scope *S, Scope *InnermostFileScope) { 101 // C++ [namespace.udir]p1: 102 // During unqualified name lookup, the names appear as if they 103 // were declared in the nearest enclosing namespace which contains 104 // both the using-directive and the nominated namespace. 105 DeclContext *InnermostFileDC 106 = static_cast<DeclContext*>(InnermostFileScope->getEntity()); 107 assert(InnermostFileDC && InnermostFileDC->isFileContext()); 108 109 for (; S; S = S->getParent()) { 110 // C++ [namespace.udir]p1: 111 // A using-directive shall not appear in class scope, but may 112 // appear in namespace scope or in block scope. 113 DeclContext *Ctx = static_cast<DeclContext*>(S->getEntity()); 114 if (Ctx && Ctx->isFileContext()) { 115 visit(Ctx, Ctx); 116 } else if (!Ctx || Ctx->isFunctionOrMethod()) { 117 Scope::udir_iterator I = S->using_directives_begin(), 118 End = S->using_directives_end(); 119 for (; I != End; ++I) 120 visit(*I, InnermostFileDC); 121 } 122 } 123 } 124 125 // Visits a context and collect all of its using directives 126 // recursively. Treats all using directives as if they were 127 // declared in the context. 128 // 129 // A given context is only every visited once, so it is important 130 // that contexts be visited from the inside out in order to get 131 // the effective DCs right. 132 void visit(DeclContext *DC, DeclContext *EffectiveDC) { 133 if (!visited.insert(DC)) 134 return; 135 136 addUsingDirectives(DC, EffectiveDC); 137 } 138 139 // Visits a using directive and collects all of its using 140 // directives recursively. Treats all using directives as if they 141 // were declared in the effective DC. 142 void visit(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) { 143 DeclContext *NS = UD->getNominatedNamespace(); 144 if (!visited.insert(NS)) 145 return; 146 147 addUsingDirective(UD, EffectiveDC); 148 addUsingDirectives(NS, EffectiveDC); 149 } 150 151 // Adds all the using directives in a context (and those nominated 152 // by its using directives, transitively) as if they appeared in 153 // the given effective context. 154 void addUsingDirectives(DeclContext *DC, DeclContext *EffectiveDC) { 155 SmallVector<DeclContext*,4> queue; 156 while (true) { 157 DeclContext::udir_iterator I, End; 158 for (llvm::tie(I, End) = DC->getUsingDirectives(); I != End; ++I) { 159 UsingDirectiveDecl *UD = *I; 160 DeclContext *NS = UD->getNominatedNamespace(); 161 if (visited.insert(NS)) { 162 addUsingDirective(UD, EffectiveDC); 163 queue.push_back(NS); 164 } 165 } 166 167 if (queue.empty()) 168 return; 169 170 DC = queue.back(); 171 queue.pop_back(); 172 } 173 } 174 175 // Add a using directive as if it had been declared in the given 176 // context. This helps implement C++ [namespace.udir]p3: 177 // The using-directive is transitive: if a scope contains a 178 // using-directive that nominates a second namespace that itself 179 // contains using-directives, the effect is as if the 180 // using-directives from the second namespace also appeared in 181 // the first. 182 void addUsingDirective(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) { 183 // Find the common ancestor between the effective context and 184 // the nominated namespace. 185 DeclContext *Common = UD->getNominatedNamespace(); 186 while (!Common->Encloses(EffectiveDC)) 187 Common = Common->getParent(); 188 Common = Common->getPrimaryContext(); 189 190 list.push_back(UnqualUsingEntry(UD->getNominatedNamespace(), Common)); 191 } 192 193 void done() { 194 std::sort(list.begin(), list.end(), UnqualUsingEntry::Comparator()); 195 } 196 197 typedef ListTy::const_iterator const_iterator; 198 199 const_iterator begin() const { return list.begin(); } 200 const_iterator end() const { return list.end(); } 201 202 std::pair<const_iterator,const_iterator> 203 getNamespacesFor(DeclContext *DC) const { 204 return std::equal_range(begin(), end(), DC->getPrimaryContext(), 205 UnqualUsingEntry::Comparator()); 206 } 207 }; 208 } 209 210 // Retrieve the set of identifier namespaces that correspond to a 211 // specific kind of name lookup. 212 static inline unsigned getIDNS(Sema::LookupNameKind NameKind, 213 bool CPlusPlus, 214 bool Redeclaration) { 215 unsigned IDNS = 0; 216 switch (NameKind) { 217 case Sema::LookupObjCImplicitSelfParam: 218 case Sema::LookupOrdinaryName: 219 case Sema::LookupRedeclarationWithLinkage: 220 IDNS = Decl::IDNS_Ordinary; 221 if (CPlusPlus) { 222 IDNS |= Decl::IDNS_Tag | Decl::IDNS_Member | Decl::IDNS_Namespace; 223 if (Redeclaration) 224 IDNS |= Decl::IDNS_TagFriend | Decl::IDNS_OrdinaryFriend; 225 } 226 break; 227 228 case Sema::LookupOperatorName: 229 // Operator lookup is its own crazy thing; it is not the same 230 // as (e.g.) looking up an operator name for redeclaration. 231 assert(!Redeclaration && "cannot do redeclaration operator lookup"); 232 IDNS = Decl::IDNS_NonMemberOperator; 233 break; 234 235 case Sema::LookupTagName: 236 if (CPlusPlus) { 237 IDNS = Decl::IDNS_Type; 238 239 // When looking for a redeclaration of a tag name, we add: 240 // 1) TagFriend to find undeclared friend decls 241 // 2) Namespace because they can't "overload" with tag decls. 242 // 3) Tag because it includes class templates, which can't 243 // "overload" with tag decls. 244 if (Redeclaration) 245 IDNS |= Decl::IDNS_Tag | Decl::IDNS_TagFriend | Decl::IDNS_Namespace; 246 } else { 247 IDNS = Decl::IDNS_Tag; 248 } 249 break; 250 case Sema::LookupLabel: 251 IDNS = Decl::IDNS_Label; 252 break; 253 254 case Sema::LookupMemberName: 255 IDNS = Decl::IDNS_Member; 256 if (CPlusPlus) 257 IDNS |= Decl::IDNS_Tag | Decl::IDNS_Ordinary; 258 break; 259 260 case Sema::LookupNestedNameSpecifierName: 261 IDNS = Decl::IDNS_Type | Decl::IDNS_Namespace; 262 break; 263 264 case Sema::LookupNamespaceName: 265 IDNS = Decl::IDNS_Namespace; 266 break; 267 268 case Sema::LookupUsingDeclName: 269 IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag 270 | Decl::IDNS_Member | Decl::IDNS_Using; 271 break; 272 273 case Sema::LookupObjCProtocolName: 274 IDNS = Decl::IDNS_ObjCProtocol; 275 break; 276 277 case Sema::LookupAnyName: 278 IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag | Decl::IDNS_Member 279 | Decl::IDNS_Using | Decl::IDNS_Namespace | Decl::IDNS_ObjCProtocol 280 | Decl::IDNS_Type; 281 break; 282 } 283 return IDNS; 284 } 285 286 void LookupResult::configure() { 287 IDNS = getIDNS(LookupKind, SemaRef.getLangOpts().CPlusPlus, 288 isForRedeclaration()); 289 290 // If we're looking for one of the allocation or deallocation 291 // operators, make sure that the implicitly-declared new and delete 292 // operators can be found. 293 if (!isForRedeclaration()) { 294 switch (NameInfo.getName().getCXXOverloadedOperator()) { 295 case OO_New: 296 case OO_Delete: 297 case OO_Array_New: 298 case OO_Array_Delete: 299 SemaRef.DeclareGlobalNewDelete(); 300 break; 301 302 default: 303 break; 304 } 305 } 306 } 307 308 void LookupResult::sanityImpl() const { 309 // Note that this function is never called by NDEBUG builds. See 310 // LookupResult::sanity(). 311 assert(ResultKind != NotFound || Decls.size() == 0); 312 assert(ResultKind != Found || Decls.size() == 1); 313 assert(ResultKind != FoundOverloaded || Decls.size() > 1 || 314 (Decls.size() == 1 && 315 isa<FunctionTemplateDecl>((*begin())->getUnderlyingDecl()))); 316 assert(ResultKind != FoundUnresolvedValue || sanityCheckUnresolved()); 317 assert(ResultKind != Ambiguous || Decls.size() > 1 || 318 (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects || 319 Ambiguity == AmbiguousBaseSubobjectTypes))); 320 assert((Paths != NULL) == (ResultKind == Ambiguous && 321 (Ambiguity == AmbiguousBaseSubobjectTypes || 322 Ambiguity == AmbiguousBaseSubobjects))); 323 } 324 325 // Necessary because CXXBasePaths is not complete in Sema.h 326 void LookupResult::deletePaths(CXXBasePaths *Paths) { 327 delete Paths; 328 } 329 330 static NamedDecl *getVisibleDecl(NamedDecl *D); 331 332 NamedDecl *LookupResult::getAcceptableDeclSlow(NamedDecl *D) const { 333 return getVisibleDecl(D); 334 } 335 336 /// Resolves the result kind of this lookup. 337 void LookupResult::resolveKind() { 338 unsigned N = Decls.size(); 339 340 // Fast case: no possible ambiguity. 341 if (N == 0) { 342 assert(ResultKind == NotFound || ResultKind == NotFoundInCurrentInstantiation); 343 return; 344 } 345 346 // If there's a single decl, we need to examine it to decide what 347 // kind of lookup this is. 348 if (N == 1) { 349 NamedDecl *D = (*Decls.begin())->getUnderlyingDecl(); 350 if (isa<FunctionTemplateDecl>(D)) 351 ResultKind = FoundOverloaded; 352 else if (isa<UnresolvedUsingValueDecl>(D)) 353 ResultKind = FoundUnresolvedValue; 354 return; 355 } 356 357 // Don't do any extra resolution if we've already resolved as ambiguous. 358 if (ResultKind == Ambiguous) return; 359 360 llvm::SmallPtrSet<NamedDecl*, 16> Unique; 361 llvm::SmallPtrSet<QualType, 16> UniqueTypes; 362 363 bool Ambiguous = false; 364 bool HasTag = false, HasFunction = false, HasNonFunction = false; 365 bool HasFunctionTemplate = false, HasUnresolved = false; 366 367 unsigned UniqueTagIndex = 0; 368 369 unsigned I = 0; 370 while (I < N) { 371 NamedDecl *D = Decls[I]->getUnderlyingDecl(); 372 D = cast<NamedDecl>(D->getCanonicalDecl()); 373 374 // Redeclarations of types via typedef can occur both within a scope 375 // and, through using declarations and directives, across scopes. There is 376 // no ambiguity if they all refer to the same type, so unique based on the 377 // canonical type. 378 if (TypeDecl *TD = dyn_cast<TypeDecl>(D)) { 379 if (!TD->getDeclContext()->isRecord()) { 380 QualType T = SemaRef.Context.getTypeDeclType(TD); 381 if (!UniqueTypes.insert(SemaRef.Context.getCanonicalType(T))) { 382 // The type is not unique; pull something off the back and continue 383 // at this index. 384 Decls[I] = Decls[--N]; 385 continue; 386 } 387 } 388 } 389 390 if (!Unique.insert(D)) { 391 // If it's not unique, pull something off the back (and 392 // continue at this index). 393 Decls[I] = Decls[--N]; 394 continue; 395 } 396 397 // Otherwise, do some decl type analysis and then continue. 398 399 if (isa<UnresolvedUsingValueDecl>(D)) { 400 HasUnresolved = true; 401 } else if (isa<TagDecl>(D)) { 402 if (HasTag) 403 Ambiguous = true; 404 UniqueTagIndex = I; 405 HasTag = true; 406 } else if (isa<FunctionTemplateDecl>(D)) { 407 HasFunction = true; 408 HasFunctionTemplate = true; 409 } else if (isa<FunctionDecl>(D)) { 410 HasFunction = true; 411 } else { 412 if (HasNonFunction) 413 Ambiguous = true; 414 HasNonFunction = true; 415 } 416 I++; 417 } 418 419 // C++ [basic.scope.hiding]p2: 420 // A class name or enumeration name can be hidden by the name of 421 // an object, function, or enumerator declared in the same 422 // scope. If a class or enumeration name and an object, function, 423 // or enumerator are declared in the same scope (in any order) 424 // with the same name, the class or enumeration name is hidden 425 // wherever the object, function, or enumerator name is visible. 426 // But it's still an error if there are distinct tag types found, 427 // even if they're not visible. (ref?) 428 if (HideTags && HasTag && !Ambiguous && 429 (HasFunction || HasNonFunction || HasUnresolved)) { 430 if (Decls[UniqueTagIndex]->getDeclContext()->getRedeclContext()->Equals( 431 Decls[UniqueTagIndex? 0 : N-1]->getDeclContext()->getRedeclContext())) 432 Decls[UniqueTagIndex] = Decls[--N]; 433 else 434 Ambiguous = true; 435 } 436 437 Decls.set_size(N); 438 439 if (HasNonFunction && (HasFunction || HasUnresolved)) 440 Ambiguous = true; 441 442 if (Ambiguous) 443 setAmbiguous(LookupResult::AmbiguousReference); 444 else if (HasUnresolved) 445 ResultKind = LookupResult::FoundUnresolvedValue; 446 else if (N > 1 || HasFunctionTemplate) 447 ResultKind = LookupResult::FoundOverloaded; 448 else 449 ResultKind = LookupResult::Found; 450 } 451 452 void LookupResult::addDeclsFromBasePaths(const CXXBasePaths &P) { 453 CXXBasePaths::const_paths_iterator I, E; 454 DeclContext::lookup_iterator DI, DE; 455 for (I = P.begin(), E = P.end(); I != E; ++I) 456 for (llvm::tie(DI,DE) = I->Decls; DI != DE; ++DI) 457 addDecl(*DI); 458 } 459 460 void LookupResult::setAmbiguousBaseSubobjects(CXXBasePaths &P) { 461 Paths = new CXXBasePaths; 462 Paths->swap(P); 463 addDeclsFromBasePaths(*Paths); 464 resolveKind(); 465 setAmbiguous(AmbiguousBaseSubobjects); 466 } 467 468 void LookupResult::setAmbiguousBaseSubobjectTypes(CXXBasePaths &P) { 469 Paths = new CXXBasePaths; 470 Paths->swap(P); 471 addDeclsFromBasePaths(*Paths); 472 resolveKind(); 473 setAmbiguous(AmbiguousBaseSubobjectTypes); 474 } 475 476 void LookupResult::print(raw_ostream &Out) { 477 Out << Decls.size() << " result(s)"; 478 if (isAmbiguous()) Out << ", ambiguous"; 479 if (Paths) Out << ", base paths present"; 480 481 for (iterator I = begin(), E = end(); I != E; ++I) { 482 Out << "\n"; 483 (*I)->print(Out, 2); 484 } 485 } 486 487 /// \brief Lookup a builtin function, when name lookup would otherwise 488 /// fail. 489 static bool LookupBuiltin(Sema &S, LookupResult &R) { 490 Sema::LookupNameKind NameKind = R.getLookupKind(); 491 492 // If we didn't find a use of this identifier, and if the identifier 493 // corresponds to a compiler builtin, create the decl object for the builtin 494 // now, injecting it into translation unit scope, and return it. 495 if (NameKind == Sema::LookupOrdinaryName || 496 NameKind == Sema::LookupRedeclarationWithLinkage) { 497 IdentifierInfo *II = R.getLookupName().getAsIdentifierInfo(); 498 if (II) { 499 // If this is a builtin on this (or all) targets, create the decl. 500 if (unsigned BuiltinID = II->getBuiltinID()) { 501 // In C++, we don't have any predefined library functions like 502 // 'malloc'. Instead, we'll just error. 503 if (S.getLangOpts().CPlusPlus && 504 S.Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) 505 return false; 506 507 if (NamedDecl *D = S.LazilyCreateBuiltin((IdentifierInfo *)II, 508 BuiltinID, S.TUScope, 509 R.isForRedeclaration(), 510 R.getNameLoc())) { 511 R.addDecl(D); 512 return true; 513 } 514 515 if (R.isForRedeclaration()) { 516 // If we're redeclaring this function anyway, forget that 517 // this was a builtin at all. 518 S.Context.BuiltinInfo.ForgetBuiltin(BuiltinID, S.Context.Idents); 519 } 520 521 return false; 522 } 523 } 524 } 525 526 return false; 527 } 528 529 /// \brief Determine whether we can declare a special member function within 530 /// the class at this point. 531 static bool CanDeclareSpecialMemberFunction(ASTContext &Context, 532 const CXXRecordDecl *Class) { 533 // We need to have a definition for the class. 534 if (!Class->getDefinition() || Class->isDependentContext()) 535 return false; 536 537 // We can't be in the middle of defining the class. 538 if (const RecordType *RecordTy 539 = Context.getTypeDeclType(Class)->getAs<RecordType>()) 540 return !RecordTy->isBeingDefined(); 541 542 return false; 543 } 544 545 void Sema::ForceDeclarationOfImplicitMembers(CXXRecordDecl *Class) { 546 if (!CanDeclareSpecialMemberFunction(Context, Class)) 547 return; 548 549 // If the default constructor has not yet been declared, do so now. 550 if (Class->needsImplicitDefaultConstructor()) 551 DeclareImplicitDefaultConstructor(Class); 552 553 // If the copy constructor has not yet been declared, do so now. 554 if (!Class->hasDeclaredCopyConstructor()) 555 DeclareImplicitCopyConstructor(Class); 556 557 // If the copy assignment operator has not yet been declared, do so now. 558 if (!Class->hasDeclaredCopyAssignment()) 559 DeclareImplicitCopyAssignment(Class); 560 561 if (getLangOpts().CPlusPlus0x) { 562 // If the move constructor has not yet been declared, do so now. 563 if (Class->needsImplicitMoveConstructor()) 564 DeclareImplicitMoveConstructor(Class); // might not actually do it 565 566 // If the move assignment operator has not yet been declared, do so now. 567 if (Class->needsImplicitMoveAssignment()) 568 DeclareImplicitMoveAssignment(Class); // might not actually do it 569 } 570 571 // If the destructor has not yet been declared, do so now. 572 if (!Class->hasDeclaredDestructor()) 573 DeclareImplicitDestructor(Class); 574 } 575 576 /// \brief Determine whether this is the name of an implicitly-declared 577 /// special member function. 578 static bool isImplicitlyDeclaredMemberFunctionName(DeclarationName Name) { 579 switch (Name.getNameKind()) { 580 case DeclarationName::CXXConstructorName: 581 case DeclarationName::CXXDestructorName: 582 return true; 583 584 case DeclarationName::CXXOperatorName: 585 return Name.getCXXOverloadedOperator() == OO_Equal; 586 587 default: 588 break; 589 } 590 591 return false; 592 } 593 594 /// \brief If there are any implicit member functions with the given name 595 /// that need to be declared in the given declaration context, do so. 596 static void DeclareImplicitMemberFunctionsWithName(Sema &S, 597 DeclarationName Name, 598 const DeclContext *DC) { 599 if (!DC) 600 return; 601 602 switch (Name.getNameKind()) { 603 case DeclarationName::CXXConstructorName: 604 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 605 if (Record->getDefinition() && 606 CanDeclareSpecialMemberFunction(S.Context, Record)) { 607 CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record); 608 if (Record->needsImplicitDefaultConstructor()) 609 S.DeclareImplicitDefaultConstructor(Class); 610 if (!Record->hasDeclaredCopyConstructor()) 611 S.DeclareImplicitCopyConstructor(Class); 612 if (S.getLangOpts().CPlusPlus0x && 613 Record->needsImplicitMoveConstructor()) 614 S.DeclareImplicitMoveConstructor(Class); 615 } 616 break; 617 618 case DeclarationName::CXXDestructorName: 619 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 620 if (Record->getDefinition() && !Record->hasDeclaredDestructor() && 621 CanDeclareSpecialMemberFunction(S.Context, Record)) 622 S.DeclareImplicitDestructor(const_cast<CXXRecordDecl *>(Record)); 623 break; 624 625 case DeclarationName::CXXOperatorName: 626 if (Name.getCXXOverloadedOperator() != OO_Equal) 627 break; 628 629 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) { 630 if (Record->getDefinition() && 631 CanDeclareSpecialMemberFunction(S.Context, Record)) { 632 CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record); 633 if (!Record->hasDeclaredCopyAssignment()) 634 S.DeclareImplicitCopyAssignment(Class); 635 if (S.getLangOpts().CPlusPlus0x && 636 Record->needsImplicitMoveAssignment()) 637 S.DeclareImplicitMoveAssignment(Class); 638 } 639 } 640 break; 641 642 default: 643 break; 644 } 645 } 646 647 // Adds all qualifying matches for a name within a decl context to the 648 // given lookup result. Returns true if any matches were found. 649 static bool LookupDirect(Sema &S, LookupResult &R, const DeclContext *DC) { 650 bool Found = false; 651 652 // Lazily declare C++ special member functions. 653 if (S.getLangOpts().CPlusPlus) 654 DeclareImplicitMemberFunctionsWithName(S, R.getLookupName(), DC); 655 656 // Perform lookup into this declaration context. 657 DeclContext::lookup_const_iterator I, E; 658 for (llvm::tie(I, E) = DC->lookup(R.getLookupName()); I != E; ++I) { 659 NamedDecl *D = *I; 660 if ((D = R.getAcceptableDecl(D))) { 661 R.addDecl(D); 662 Found = true; 663 } 664 } 665 666 if (!Found && DC->isTranslationUnit() && LookupBuiltin(S, R)) 667 return true; 668 669 if (R.getLookupName().getNameKind() 670 != DeclarationName::CXXConversionFunctionName || 671 R.getLookupName().getCXXNameType()->isDependentType() || 672 !isa<CXXRecordDecl>(DC)) 673 return Found; 674 675 // C++ [temp.mem]p6: 676 // A specialization of a conversion function template is not found by 677 // name lookup. Instead, any conversion function templates visible in the 678 // context of the use are considered. [...] 679 const CXXRecordDecl *Record = cast<CXXRecordDecl>(DC); 680 if (!Record->isCompleteDefinition()) 681 return Found; 682 683 const UnresolvedSetImpl *Unresolved = Record->getConversionFunctions(); 684 for (UnresolvedSetImpl::iterator U = Unresolved->begin(), 685 UEnd = Unresolved->end(); U != UEnd; ++U) { 686 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(*U); 687 if (!ConvTemplate) 688 continue; 689 690 // When we're performing lookup for the purposes of redeclaration, just 691 // add the conversion function template. When we deduce template 692 // arguments for specializations, we'll end up unifying the return 693 // type of the new declaration with the type of the function template. 694 if (R.isForRedeclaration()) { 695 R.addDecl(ConvTemplate); 696 Found = true; 697 continue; 698 } 699 700 // C++ [temp.mem]p6: 701 // [...] For each such operator, if argument deduction succeeds 702 // (14.9.2.3), the resulting specialization is used as if found by 703 // name lookup. 704 // 705 // When referencing a conversion function for any purpose other than 706 // a redeclaration (such that we'll be building an expression with the 707 // result), perform template argument deduction and place the 708 // specialization into the result set. We do this to avoid forcing all 709 // callers to perform special deduction for conversion functions. 710 TemplateDeductionInfo Info(R.getSema().Context, R.getNameLoc()); 711 FunctionDecl *Specialization = 0; 712 713 const FunctionProtoType *ConvProto 714 = ConvTemplate->getTemplatedDecl()->getType()->getAs<FunctionProtoType>(); 715 assert(ConvProto && "Nonsensical conversion function template type"); 716 717 // Compute the type of the function that we would expect the conversion 718 // function to have, if it were to match the name given. 719 // FIXME: Calling convention! 720 FunctionProtoType::ExtProtoInfo EPI = ConvProto->getExtProtoInfo(); 721 EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC_Default); 722 EPI.ExceptionSpecType = EST_None; 723 EPI.NumExceptions = 0; 724 QualType ExpectedType 725 = R.getSema().Context.getFunctionType(R.getLookupName().getCXXNameType(), 726 0, 0, EPI); 727 728 // Perform template argument deduction against the type that we would 729 // expect the function to have. 730 if (R.getSema().DeduceTemplateArguments(ConvTemplate, 0, ExpectedType, 731 Specialization, Info) 732 == Sema::TDK_Success) { 733 R.addDecl(Specialization); 734 Found = true; 735 } 736 } 737 738 return Found; 739 } 740 741 // Performs C++ unqualified lookup into the given file context. 742 static bool 743 CppNamespaceLookup(Sema &S, LookupResult &R, ASTContext &Context, 744 DeclContext *NS, UnqualUsingDirectiveSet &UDirs) { 745 746 assert(NS && NS->isFileContext() && "CppNamespaceLookup() requires namespace!"); 747 748 // Perform direct name lookup into the LookupCtx. 749 bool Found = LookupDirect(S, R, NS); 750 751 // Perform direct name lookup into the namespaces nominated by the 752 // using directives whose common ancestor is this namespace. 753 UnqualUsingDirectiveSet::const_iterator UI, UEnd; 754 llvm::tie(UI, UEnd) = UDirs.getNamespacesFor(NS); 755 756 for (; UI != UEnd; ++UI) 757 if (LookupDirect(S, R, UI->getNominatedNamespace())) 758 Found = true; 759 760 R.resolveKind(); 761 762 return Found; 763 } 764 765 static bool isNamespaceOrTranslationUnitScope(Scope *S) { 766 if (DeclContext *Ctx = static_cast<DeclContext*>(S->getEntity())) 767 return Ctx->isFileContext(); 768 return false; 769 } 770 771 // Find the next outer declaration context from this scope. This 772 // routine actually returns the semantic outer context, which may 773 // differ from the lexical context (encoded directly in the Scope 774 // stack) when we are parsing a member of a class template. In this 775 // case, the second element of the pair will be true, to indicate that 776 // name lookup should continue searching in this semantic context when 777 // it leaves the current template parameter scope. 778 static std::pair<DeclContext *, bool> findOuterContext(Scope *S) { 779 DeclContext *DC = static_cast<DeclContext *>(S->getEntity()); 780 DeclContext *Lexical = 0; 781 for (Scope *OuterS = S->getParent(); OuterS; 782 OuterS = OuterS->getParent()) { 783 if (OuterS->getEntity()) { 784 Lexical = static_cast<DeclContext *>(OuterS->getEntity()); 785 break; 786 } 787 } 788 789 // C++ [temp.local]p8: 790 // In the definition of a member of a class template that appears 791 // outside of the namespace containing the class template 792 // definition, the name of a template-parameter hides the name of 793 // a member of this namespace. 794 // 795 // Example: 796 // 797 // namespace N { 798 // class C { }; 799 // 800 // template<class T> class B { 801 // void f(T); 802 // }; 803 // } 804 // 805 // template<class C> void N::B<C>::f(C) { 806 // C b; // C is the template parameter, not N::C 807 // } 808 // 809 // In this example, the lexical context we return is the 810 // TranslationUnit, while the semantic context is the namespace N. 811 if (!Lexical || !DC || !S->getParent() || 812 !S->getParent()->isTemplateParamScope()) 813 return std::make_pair(Lexical, false); 814 815 // Find the outermost template parameter scope. 816 // For the example, this is the scope for the template parameters of 817 // template<class C>. 818 Scope *OutermostTemplateScope = S->getParent(); 819 while (OutermostTemplateScope->getParent() && 820 OutermostTemplateScope->getParent()->isTemplateParamScope()) 821 OutermostTemplateScope = OutermostTemplateScope->getParent(); 822 823 // Find the namespace context in which the original scope occurs. In 824 // the example, this is namespace N. 825 DeclContext *Semantic = DC; 826 while (!Semantic->isFileContext()) 827 Semantic = Semantic->getParent(); 828 829 // Find the declaration context just outside of the template 830 // parameter scope. This is the context in which the template is 831 // being lexically declaration (a namespace context). In the 832 // example, this is the global scope. 833 if (Lexical->isFileContext() && !Lexical->Equals(Semantic) && 834 Lexical->Encloses(Semantic)) 835 return std::make_pair(Semantic, true); 836 837 return std::make_pair(Lexical, false); 838 } 839 840 bool Sema::CppLookupName(LookupResult &R, Scope *S) { 841 assert(getLangOpts().CPlusPlus && "Can perform only C++ lookup"); 842 843 DeclarationName Name = R.getLookupName(); 844 845 // If this is the name of an implicitly-declared special member function, 846 // go through the scope stack to implicitly declare 847 if (isImplicitlyDeclaredMemberFunctionName(Name)) { 848 for (Scope *PreS = S; PreS; PreS = PreS->getParent()) 849 if (DeclContext *DC = static_cast<DeclContext *>(PreS->getEntity())) 850 DeclareImplicitMemberFunctionsWithName(*this, Name, DC); 851 } 852 853 // Implicitly declare member functions with the name we're looking for, if in 854 // fact we are in a scope where it matters. 855 856 Scope *Initial = S; 857 IdentifierResolver::iterator 858 I = IdResolver.begin(Name), 859 IEnd = IdResolver.end(); 860 861 // First we lookup local scope. 862 // We don't consider using-directives, as per 7.3.4.p1 [namespace.udir] 863 // ...During unqualified name lookup (3.4.1), the names appear as if 864 // they were declared in the nearest enclosing namespace which contains 865 // both the using-directive and the nominated namespace. 866 // [Note: in this context, "contains" means "contains directly or 867 // indirectly". 868 // 869 // For example: 870 // namespace A { int i; } 871 // void foo() { 872 // int i; 873 // { 874 // using namespace A; 875 // ++i; // finds local 'i', A::i appears at global scope 876 // } 877 // } 878 // 879 DeclContext *OutsideOfTemplateParamDC = 0; 880 for (; S && !isNamespaceOrTranslationUnitScope(S); S = S->getParent()) { 881 DeclContext *Ctx = static_cast<DeclContext*>(S->getEntity()); 882 883 // Check whether the IdResolver has anything in this scope. 884 bool Found = false; 885 for (; I != IEnd && S->isDeclScope(*I); ++I) { 886 if (NamedDecl *ND = R.getAcceptableDecl(*I)) { 887 Found = true; 888 R.addDecl(ND); 889 } 890 } 891 if (Found) { 892 R.resolveKind(); 893 if (S->isClassScope()) 894 if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(Ctx)) 895 R.setNamingClass(Record); 896 return true; 897 } 898 899 if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC && 900 S->getParent() && !S->getParent()->isTemplateParamScope()) { 901 // We've just searched the last template parameter scope and 902 // found nothing, so look into the the contexts between the 903 // lexical and semantic declaration contexts returned by 904 // findOuterContext(). This implements the name lookup behavior 905 // of C++ [temp.local]p8. 906 Ctx = OutsideOfTemplateParamDC; 907 OutsideOfTemplateParamDC = 0; 908 } 909 910 if (Ctx) { 911 DeclContext *OuterCtx; 912 bool SearchAfterTemplateScope; 913 llvm::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S); 914 if (SearchAfterTemplateScope) 915 OutsideOfTemplateParamDC = OuterCtx; 916 917 for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) { 918 // We do not directly look into transparent contexts, since 919 // those entities will be found in the nearest enclosing 920 // non-transparent context. 921 if (Ctx->isTransparentContext()) 922 continue; 923 924 // We do not look directly into function or method contexts, 925 // since all of the local variables and parameters of the 926 // function/method are present within the Scope. 927 if (Ctx->isFunctionOrMethod()) { 928 // If we have an Objective-C instance method, look for ivars 929 // in the corresponding interface. 930 if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) { 931 if (Method->isInstanceMethod() && Name.getAsIdentifierInfo()) 932 if (ObjCInterfaceDecl *Class = Method->getClassInterface()) { 933 ObjCInterfaceDecl *ClassDeclared; 934 if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable( 935 Name.getAsIdentifierInfo(), 936 ClassDeclared)) { 937 if (NamedDecl *ND = R.getAcceptableDecl(Ivar)) { 938 R.addDecl(ND); 939 R.resolveKind(); 940 return true; 941 } 942 } 943 } 944 } 945 946 continue; 947 } 948 949 // Perform qualified name lookup into this context. 950 // FIXME: In some cases, we know that every name that could be found by 951 // this qualified name lookup will also be on the identifier chain. For 952 // example, inside a class without any base classes, we never need to 953 // perform qualified lookup because all of the members are on top of the 954 // identifier chain. 955 if (LookupQualifiedName(R, Ctx, /*InUnqualifiedLookup=*/true)) 956 return true; 957 } 958 } 959 } 960 961 // Stop if we ran out of scopes. 962 // FIXME: This really, really shouldn't be happening. 963 if (!S) return false; 964 965 // If we are looking for members, no need to look into global/namespace scope. 966 if (R.getLookupKind() == LookupMemberName) 967 return false; 968 969 // Collect UsingDirectiveDecls in all scopes, and recursively all 970 // nominated namespaces by those using-directives. 971 // 972 // FIXME: Cache this sorted list in Scope structure, and DeclContext, so we 973 // don't build it for each lookup! 974 975 UnqualUsingDirectiveSet UDirs; 976 UDirs.visitScopeChain(Initial, S); 977 UDirs.done(); 978 979 // Lookup namespace scope, and global scope. 980 // Unqualified name lookup in C++ requires looking into scopes 981 // that aren't strictly lexical, and therefore we walk through the 982 // context as well as walking through the scopes. 983 984 for (; S; S = S->getParent()) { 985 // Check whether the IdResolver has anything in this scope. 986 bool Found = false; 987 for (; I != IEnd && S->isDeclScope(*I); ++I) { 988 if (NamedDecl *ND = R.getAcceptableDecl(*I)) { 989 // We found something. Look for anything else in our scope 990 // with this same name and in an acceptable identifier 991 // namespace, so that we can construct an overload set if we 992 // need to. 993 Found = true; 994 R.addDecl(ND); 995 } 996 } 997 998 if (Found && S->isTemplateParamScope()) { 999 R.resolveKind(); 1000 return true; 1001 } 1002 1003 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 1004 if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC && 1005 S->getParent() && !S->getParent()->isTemplateParamScope()) { 1006 // We've just searched the last template parameter scope and 1007 // found nothing, so look into the the contexts between the 1008 // lexical and semantic declaration contexts returned by 1009 // findOuterContext(). This implements the name lookup behavior 1010 // of C++ [temp.local]p8. 1011 Ctx = OutsideOfTemplateParamDC; 1012 OutsideOfTemplateParamDC = 0; 1013 } 1014 1015 if (Ctx) { 1016 DeclContext *OuterCtx; 1017 bool SearchAfterTemplateScope; 1018 llvm::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S); 1019 if (SearchAfterTemplateScope) 1020 OutsideOfTemplateParamDC = OuterCtx; 1021 1022 for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) { 1023 // We do not directly look into transparent contexts, since 1024 // those entities will be found in the nearest enclosing 1025 // non-transparent context. 1026 if (Ctx->isTransparentContext()) 1027 continue; 1028 1029 // If we have a context, and it's not a context stashed in the 1030 // template parameter scope for an out-of-line definition, also 1031 // look into that context. 1032 if (!(Found && S && S->isTemplateParamScope())) { 1033 assert(Ctx->isFileContext() && 1034 "We should have been looking only at file context here already."); 1035 1036 // Look into context considering using-directives. 1037 if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs)) 1038 Found = true; 1039 } 1040 1041 if (Found) { 1042 R.resolveKind(); 1043 return true; 1044 } 1045 1046 if (R.isForRedeclaration() && !Ctx->isTransparentContext()) 1047 return false; 1048 } 1049 } 1050 1051 if (R.isForRedeclaration() && Ctx && !Ctx->isTransparentContext()) 1052 return false; 1053 } 1054 1055 return !R.empty(); 1056 } 1057 1058 /// \brief Retrieve the visible declaration corresponding to D, if any. 1059 /// 1060 /// This routine determines whether the declaration D is visible in the current 1061 /// module, with the current imports. If not, it checks whether any 1062 /// redeclaration of D is visible, and if so, returns that declaration. 1063 /// 1064 /// \returns D, or a visible previous declaration of D, whichever is more recent 1065 /// and visible. If no declaration of D is visible, returns null. 1066 static NamedDecl *getVisibleDecl(NamedDecl *D) { 1067 if (LookupResult::isVisible(D)) 1068 return D; 1069 1070 for (Decl::redecl_iterator RD = D->redecls_begin(), RDEnd = D->redecls_end(); 1071 RD != RDEnd; ++RD) { 1072 if (NamedDecl *ND = dyn_cast<NamedDecl>(*RD)) { 1073 if (LookupResult::isVisible(ND)) 1074 return ND; 1075 } 1076 } 1077 1078 return 0; 1079 } 1080 1081 /// @brief Perform unqualified name lookup starting from a given 1082 /// scope. 1083 /// 1084 /// Unqualified name lookup (C++ [basic.lookup.unqual], C99 6.2.1) is 1085 /// used to find names within the current scope. For example, 'x' in 1086 /// @code 1087 /// int x; 1088 /// int f() { 1089 /// return x; // unqualified name look finds 'x' in the global scope 1090 /// } 1091 /// @endcode 1092 /// 1093 /// Different lookup criteria can find different names. For example, a 1094 /// particular scope can have both a struct and a function of the same 1095 /// name, and each can be found by certain lookup criteria. For more 1096 /// information about lookup criteria, see the documentation for the 1097 /// class LookupCriteria. 1098 /// 1099 /// @param S The scope from which unqualified name lookup will 1100 /// begin. If the lookup criteria permits, name lookup may also search 1101 /// in the parent scopes. 1102 /// 1103 /// @param Name The name of the entity that we are searching for. 1104 /// 1105 /// @param Loc If provided, the source location where we're performing 1106 /// name lookup. At present, this is only used to produce diagnostics when 1107 /// C library functions (like "malloc") are implicitly declared. 1108 /// 1109 /// @returns The result of name lookup, which includes zero or more 1110 /// declarations and possibly additional information used to diagnose 1111 /// ambiguities. 1112 bool Sema::LookupName(LookupResult &R, Scope *S, bool AllowBuiltinCreation) { 1113 DeclarationName Name = R.getLookupName(); 1114 if (!Name) return false; 1115 1116 LookupNameKind NameKind = R.getLookupKind(); 1117 1118 if (!getLangOpts().CPlusPlus) { 1119 // Unqualified name lookup in C/Objective-C is purely lexical, so 1120 // search in the declarations attached to the name. 1121 if (NameKind == Sema::LookupRedeclarationWithLinkage) { 1122 // Find the nearest non-transparent declaration scope. 1123 while (!(S->getFlags() & Scope::DeclScope) || 1124 (S->getEntity() && 1125 static_cast<DeclContext *>(S->getEntity()) 1126 ->isTransparentContext())) 1127 S = S->getParent(); 1128 } 1129 1130 unsigned IDNS = R.getIdentifierNamespace(); 1131 1132 // Scan up the scope chain looking for a decl that matches this 1133 // identifier that is in the appropriate namespace. This search 1134 // should not take long, as shadowing of names is uncommon, and 1135 // deep shadowing is extremely uncommon. 1136 bool LeftStartingScope = false; 1137 1138 for (IdentifierResolver::iterator I = IdResolver.begin(Name), 1139 IEnd = IdResolver.end(); 1140 I != IEnd; ++I) 1141 if ((*I)->isInIdentifierNamespace(IDNS)) { 1142 if (NameKind == LookupRedeclarationWithLinkage) { 1143 // Determine whether this (or a previous) declaration is 1144 // out-of-scope. 1145 if (!LeftStartingScope && !S->isDeclScope(*I)) 1146 LeftStartingScope = true; 1147 1148 // If we found something outside of our starting scope that 1149 // does not have linkage, skip it. 1150 if (LeftStartingScope && !((*I)->hasLinkage())) 1151 continue; 1152 } 1153 else if (NameKind == LookupObjCImplicitSelfParam && 1154 !isa<ImplicitParamDecl>(*I)) 1155 continue; 1156 1157 // If this declaration is module-private and it came from an AST 1158 // file, we can't see it. 1159 NamedDecl *D = R.isHiddenDeclarationVisible()? *I : getVisibleDecl(*I); 1160 if (!D) 1161 continue; 1162 1163 R.addDecl(D); 1164 1165 // Check whether there are any other declarations with the same name 1166 // and in the same scope. 1167 if (I != IEnd) { 1168 // Find the scope in which this declaration was declared (if it 1169 // actually exists in a Scope). 1170 while (S && !S->isDeclScope(D)) 1171 S = S->getParent(); 1172 1173 // If the scope containing the declaration is the translation unit, 1174 // then we'll need to perform our checks based on the matching 1175 // DeclContexts rather than matching scopes. 1176 if (S && isNamespaceOrTranslationUnitScope(S)) 1177 S = 0; 1178 1179 // Compute the DeclContext, if we need it. 1180 DeclContext *DC = 0; 1181 if (!S) 1182 DC = (*I)->getDeclContext()->getRedeclContext(); 1183 1184 IdentifierResolver::iterator LastI = I; 1185 for (++LastI; LastI != IEnd; ++LastI) { 1186 if (S) { 1187 // Match based on scope. 1188 if (!S->isDeclScope(*LastI)) 1189 break; 1190 } else { 1191 // Match based on DeclContext. 1192 DeclContext *LastDC 1193 = (*LastI)->getDeclContext()->getRedeclContext(); 1194 if (!LastDC->Equals(DC)) 1195 break; 1196 } 1197 1198 // If the declaration isn't in the right namespace, skip it. 1199 if (!(*LastI)->isInIdentifierNamespace(IDNS)) 1200 continue; 1201 1202 D = R.isHiddenDeclarationVisible()? *LastI : getVisibleDecl(*LastI); 1203 if (D) 1204 R.addDecl(D); 1205 } 1206 1207 R.resolveKind(); 1208 } 1209 return true; 1210 } 1211 } else { 1212 // Perform C++ unqualified name lookup. 1213 if (CppLookupName(R, S)) 1214 return true; 1215 } 1216 1217 // If we didn't find a use of this identifier, and if the identifier 1218 // corresponds to a compiler builtin, create the decl object for the builtin 1219 // now, injecting it into translation unit scope, and return it. 1220 if (AllowBuiltinCreation && LookupBuiltin(*this, R)) 1221 return true; 1222 1223 // If we didn't find a use of this identifier, the ExternalSource 1224 // may be able to handle the situation. 1225 // Note: some lookup failures are expected! 1226 // See e.g. R.isForRedeclaration(). 1227 return (ExternalSource && ExternalSource->LookupUnqualified(R, S)); 1228 } 1229 1230 /// @brief Perform qualified name lookup in the namespaces nominated by 1231 /// using directives by the given context. 1232 /// 1233 /// C++98 [namespace.qual]p2: 1234 /// Given X::m (where X is a user-declared namespace), or given ::m 1235 /// (where X is the global namespace), let S be the set of all 1236 /// declarations of m in X and in the transitive closure of all 1237 /// namespaces nominated by using-directives in X and its used 1238 /// namespaces, except that using-directives are ignored in any 1239 /// namespace, including X, directly containing one or more 1240 /// declarations of m. No namespace is searched more than once in 1241 /// the lookup of a name. If S is the empty set, the program is 1242 /// ill-formed. Otherwise, if S has exactly one member, or if the 1243 /// context of the reference is a using-declaration 1244 /// (namespace.udecl), S is the required set of declarations of 1245 /// m. Otherwise if the use of m is not one that allows a unique 1246 /// declaration to be chosen from S, the program is ill-formed. 1247 /// C++98 [namespace.qual]p5: 1248 /// During the lookup of a qualified namespace member name, if the 1249 /// lookup finds more than one declaration of the member, and if one 1250 /// declaration introduces a class name or enumeration name and the 1251 /// other declarations either introduce the same object, the same 1252 /// enumerator or a set of functions, the non-type name hides the 1253 /// class or enumeration name if and only if the declarations are 1254 /// from the same namespace; otherwise (the declarations are from 1255 /// different namespaces), the program is ill-formed. 1256 static bool LookupQualifiedNameInUsingDirectives(Sema &S, LookupResult &R, 1257 DeclContext *StartDC) { 1258 assert(StartDC->isFileContext() && "start context is not a file context"); 1259 1260 DeclContext::udir_iterator I = StartDC->using_directives_begin(); 1261 DeclContext::udir_iterator E = StartDC->using_directives_end(); 1262 1263 if (I == E) return false; 1264 1265 // We have at least added all these contexts to the queue. 1266 llvm::SmallPtrSet<DeclContext*, 8> Visited; 1267 Visited.insert(StartDC); 1268 1269 // We have not yet looked into these namespaces, much less added 1270 // their "using-children" to the queue. 1271 SmallVector<NamespaceDecl*, 8> Queue; 1272 1273 // We have already looked into the initial namespace; seed the queue 1274 // with its using-children. 1275 for (; I != E; ++I) { 1276 NamespaceDecl *ND = (*I)->getNominatedNamespace()->getOriginalNamespace(); 1277 if (Visited.insert(ND)) 1278 Queue.push_back(ND); 1279 } 1280 1281 // The easiest way to implement the restriction in [namespace.qual]p5 1282 // is to check whether any of the individual results found a tag 1283 // and, if so, to declare an ambiguity if the final result is not 1284 // a tag. 1285 bool FoundTag = false; 1286 bool FoundNonTag = false; 1287 1288 LookupResult LocalR(LookupResult::Temporary, R); 1289 1290 bool Found = false; 1291 while (!Queue.empty()) { 1292 NamespaceDecl *ND = Queue.back(); 1293 Queue.pop_back(); 1294 1295 // We go through some convolutions here to avoid copying results 1296 // between LookupResults. 1297 bool UseLocal = !R.empty(); 1298 LookupResult &DirectR = UseLocal ? LocalR : R; 1299 bool FoundDirect = LookupDirect(S, DirectR, ND); 1300 1301 if (FoundDirect) { 1302 // First do any local hiding. 1303 DirectR.resolveKind(); 1304 1305 // If the local result is a tag, remember that. 1306 if (DirectR.isSingleTagDecl()) 1307 FoundTag = true; 1308 else 1309 FoundNonTag = true; 1310 1311 // Append the local results to the total results if necessary. 1312 if (UseLocal) { 1313 R.addAllDecls(LocalR); 1314 LocalR.clear(); 1315 } 1316 } 1317 1318 // If we find names in this namespace, ignore its using directives. 1319 if (FoundDirect) { 1320 Found = true; 1321 continue; 1322 } 1323 1324 for (llvm::tie(I,E) = ND->getUsingDirectives(); I != E; ++I) { 1325 NamespaceDecl *Nom = (*I)->getNominatedNamespace(); 1326 if (Visited.insert(Nom)) 1327 Queue.push_back(Nom); 1328 } 1329 } 1330 1331 if (Found) { 1332 if (FoundTag && FoundNonTag) 1333 R.setAmbiguousQualifiedTagHiding(); 1334 else 1335 R.resolveKind(); 1336 } 1337 1338 return Found; 1339 } 1340 1341 /// \brief Callback that looks for any member of a class with the given name. 1342 static bool LookupAnyMember(const CXXBaseSpecifier *Specifier, 1343 CXXBasePath &Path, 1344 void *Name) { 1345 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 1346 1347 DeclarationName N = DeclarationName::getFromOpaquePtr(Name); 1348 Path.Decls = BaseRecord->lookup(N); 1349 return Path.Decls.first != Path.Decls.second; 1350 } 1351 1352 /// \brief Determine whether the given set of member declarations contains only 1353 /// static members, nested types, and enumerators. 1354 template<typename InputIterator> 1355 static bool HasOnlyStaticMembers(InputIterator First, InputIterator Last) { 1356 Decl *D = (*First)->getUnderlyingDecl(); 1357 if (isa<VarDecl>(D) || isa<TypeDecl>(D) || isa<EnumConstantDecl>(D)) 1358 return true; 1359 1360 if (isa<CXXMethodDecl>(D)) { 1361 // Determine whether all of the methods are static. 1362 bool AllMethodsAreStatic = true; 1363 for(; First != Last; ++First) { 1364 D = (*First)->getUnderlyingDecl(); 1365 1366 if (!isa<CXXMethodDecl>(D)) { 1367 assert(isa<TagDecl>(D) && "Non-function must be a tag decl"); 1368 break; 1369 } 1370 1371 if (!cast<CXXMethodDecl>(D)->isStatic()) { 1372 AllMethodsAreStatic = false; 1373 break; 1374 } 1375 } 1376 1377 if (AllMethodsAreStatic) 1378 return true; 1379 } 1380 1381 return false; 1382 } 1383 1384 /// \brief Perform qualified name lookup into a given context. 1385 /// 1386 /// Qualified name lookup (C++ [basic.lookup.qual]) is used to find 1387 /// names when the context of those names is explicit specified, e.g., 1388 /// "std::vector" or "x->member", or as part of unqualified name lookup. 1389 /// 1390 /// Different lookup criteria can find different names. For example, a 1391 /// particular scope can have both a struct and a function of the same 1392 /// name, and each can be found by certain lookup criteria. For more 1393 /// information about lookup criteria, see the documentation for the 1394 /// class LookupCriteria. 1395 /// 1396 /// \param R captures both the lookup criteria and any lookup results found. 1397 /// 1398 /// \param LookupCtx The context in which qualified name lookup will 1399 /// search. If the lookup criteria permits, name lookup may also search 1400 /// in the parent contexts or (for C++ classes) base classes. 1401 /// 1402 /// \param InUnqualifiedLookup true if this is qualified name lookup that 1403 /// occurs as part of unqualified name lookup. 1404 /// 1405 /// \returns true if lookup succeeded, false if it failed. 1406 bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx, 1407 bool InUnqualifiedLookup) { 1408 assert(LookupCtx && "Sema::LookupQualifiedName requires a lookup context"); 1409 1410 if (!R.getLookupName()) 1411 return false; 1412 1413 // Make sure that the declaration context is complete. 1414 assert((!isa<TagDecl>(LookupCtx) || 1415 LookupCtx->isDependentContext() || 1416 cast<TagDecl>(LookupCtx)->isCompleteDefinition() || 1417 cast<TagDecl>(LookupCtx)->isBeingDefined()) && 1418 "Declaration context must already be complete!"); 1419 1420 // Perform qualified name lookup into the LookupCtx. 1421 if (LookupDirect(*this, R, LookupCtx)) { 1422 R.resolveKind(); 1423 if (isa<CXXRecordDecl>(LookupCtx)) 1424 R.setNamingClass(cast<CXXRecordDecl>(LookupCtx)); 1425 return true; 1426 } 1427 1428 // Don't descend into implied contexts for redeclarations. 1429 // C++98 [namespace.qual]p6: 1430 // In a declaration for a namespace member in which the 1431 // declarator-id is a qualified-id, given that the qualified-id 1432 // for the namespace member has the form 1433 // nested-name-specifier unqualified-id 1434 // the unqualified-id shall name a member of the namespace 1435 // designated by the nested-name-specifier. 1436 // See also [class.mfct]p5 and [class.static.data]p2. 1437 if (R.isForRedeclaration()) 1438 return false; 1439 1440 // If this is a namespace, look it up in the implied namespaces. 1441 if (LookupCtx->isFileContext()) 1442 return LookupQualifiedNameInUsingDirectives(*this, R, LookupCtx); 1443 1444 // If this isn't a C++ class, we aren't allowed to look into base 1445 // classes, we're done. 1446 CXXRecordDecl *LookupRec = dyn_cast<CXXRecordDecl>(LookupCtx); 1447 if (!LookupRec || !LookupRec->getDefinition()) 1448 return false; 1449 1450 // If we're performing qualified name lookup into a dependent class, 1451 // then we are actually looking into a current instantiation. If we have any 1452 // dependent base classes, then we either have to delay lookup until 1453 // template instantiation time (at which point all bases will be available) 1454 // or we have to fail. 1455 if (!InUnqualifiedLookup && LookupRec->isDependentContext() && 1456 LookupRec->hasAnyDependentBases()) { 1457 R.setNotFoundInCurrentInstantiation(); 1458 return false; 1459 } 1460 1461 // Perform lookup into our base classes. 1462 CXXBasePaths Paths; 1463 Paths.setOrigin(LookupRec); 1464 1465 // Look for this member in our base classes 1466 CXXRecordDecl::BaseMatchesCallback *BaseCallback = 0; 1467 switch (R.getLookupKind()) { 1468 case LookupObjCImplicitSelfParam: 1469 case LookupOrdinaryName: 1470 case LookupMemberName: 1471 case LookupRedeclarationWithLinkage: 1472 BaseCallback = &CXXRecordDecl::FindOrdinaryMember; 1473 break; 1474 1475 case LookupTagName: 1476 BaseCallback = &CXXRecordDecl::FindTagMember; 1477 break; 1478 1479 case LookupAnyName: 1480 BaseCallback = &LookupAnyMember; 1481 break; 1482 1483 case LookupUsingDeclName: 1484 // This lookup is for redeclarations only. 1485 1486 case LookupOperatorName: 1487 case LookupNamespaceName: 1488 case LookupObjCProtocolName: 1489 case LookupLabel: 1490 // These lookups will never find a member in a C++ class (or base class). 1491 return false; 1492 1493 case LookupNestedNameSpecifierName: 1494 BaseCallback = &CXXRecordDecl::FindNestedNameSpecifierMember; 1495 break; 1496 } 1497 1498 if (!LookupRec->lookupInBases(BaseCallback, 1499 R.getLookupName().getAsOpaquePtr(), Paths)) 1500 return false; 1501 1502 R.setNamingClass(LookupRec); 1503 1504 // C++ [class.member.lookup]p2: 1505 // [...] If the resulting set of declarations are not all from 1506 // sub-objects of the same type, or the set has a nonstatic member 1507 // and includes members from distinct sub-objects, there is an 1508 // ambiguity and the program is ill-formed. Otherwise that set is 1509 // the result of the lookup. 1510 QualType SubobjectType; 1511 int SubobjectNumber = 0; 1512 AccessSpecifier SubobjectAccess = AS_none; 1513 1514 for (CXXBasePaths::paths_iterator Path = Paths.begin(), PathEnd = Paths.end(); 1515 Path != PathEnd; ++Path) { 1516 const CXXBasePathElement &PathElement = Path->back(); 1517 1518 // Pick the best (i.e. most permissive i.e. numerically lowest) access 1519 // across all paths. 1520 SubobjectAccess = std::min(SubobjectAccess, Path->Access); 1521 1522 // Determine whether we're looking at a distinct sub-object or not. 1523 if (SubobjectType.isNull()) { 1524 // This is the first subobject we've looked at. Record its type. 1525 SubobjectType = Context.getCanonicalType(PathElement.Base->getType()); 1526 SubobjectNumber = PathElement.SubobjectNumber; 1527 continue; 1528 } 1529 1530 if (SubobjectType 1531 != Context.getCanonicalType(PathElement.Base->getType())) { 1532 // We found members of the given name in two subobjects of 1533 // different types. If the declaration sets aren't the same, this 1534 // this lookup is ambiguous. 1535 if (HasOnlyStaticMembers(Path->Decls.first, Path->Decls.second)) { 1536 CXXBasePaths::paths_iterator FirstPath = Paths.begin(); 1537 DeclContext::lookup_iterator FirstD = FirstPath->Decls.first; 1538 DeclContext::lookup_iterator CurrentD = Path->Decls.first; 1539 1540 while (FirstD != FirstPath->Decls.second && 1541 CurrentD != Path->Decls.second) { 1542 if ((*FirstD)->getUnderlyingDecl()->getCanonicalDecl() != 1543 (*CurrentD)->getUnderlyingDecl()->getCanonicalDecl()) 1544 break; 1545 1546 ++FirstD; 1547 ++CurrentD; 1548 } 1549 1550 if (FirstD == FirstPath->Decls.second && 1551 CurrentD == Path->Decls.second) 1552 continue; 1553 } 1554 1555 R.setAmbiguousBaseSubobjectTypes(Paths); 1556 return true; 1557 } 1558 1559 if (SubobjectNumber != PathElement.SubobjectNumber) { 1560 // We have a different subobject of the same type. 1561 1562 // C++ [class.member.lookup]p5: 1563 // A static member, a nested type or an enumerator defined in 1564 // a base class T can unambiguously be found even if an object 1565 // has more than one base class subobject of type T. 1566 if (HasOnlyStaticMembers(Path->Decls.first, Path->Decls.second)) 1567 continue; 1568 1569 // We have found a nonstatic member name in multiple, distinct 1570 // subobjects. Name lookup is ambiguous. 1571 R.setAmbiguousBaseSubobjects(Paths); 1572 return true; 1573 } 1574 } 1575 1576 // Lookup in a base class succeeded; return these results. 1577 1578 DeclContext::lookup_iterator I, E; 1579 for (llvm::tie(I,E) = Paths.front().Decls; I != E; ++I) { 1580 NamedDecl *D = *I; 1581 AccessSpecifier AS = CXXRecordDecl::MergeAccess(SubobjectAccess, 1582 D->getAccess()); 1583 R.addDecl(D, AS); 1584 } 1585 R.resolveKind(); 1586 return true; 1587 } 1588 1589 /// @brief Performs name lookup for a name that was parsed in the 1590 /// source code, and may contain a C++ scope specifier. 1591 /// 1592 /// This routine is a convenience routine meant to be called from 1593 /// contexts that receive a name and an optional C++ scope specifier 1594 /// (e.g., "N::M::x"). It will then perform either qualified or 1595 /// unqualified name lookup (with LookupQualifiedName or LookupName, 1596 /// respectively) on the given name and return those results. 1597 /// 1598 /// @param S The scope from which unqualified name lookup will 1599 /// begin. 1600 /// 1601 /// @param SS An optional C++ scope-specifier, e.g., "::N::M". 1602 /// 1603 /// @param EnteringContext Indicates whether we are going to enter the 1604 /// context of the scope-specifier SS (if present). 1605 /// 1606 /// @returns True if any decls were found (but possibly ambiguous) 1607 bool Sema::LookupParsedName(LookupResult &R, Scope *S, CXXScopeSpec *SS, 1608 bool AllowBuiltinCreation, bool EnteringContext) { 1609 if (SS && SS->isInvalid()) { 1610 // When the scope specifier is invalid, don't even look for 1611 // anything. 1612 return false; 1613 } 1614 1615 if (SS && SS->isSet()) { 1616 if (DeclContext *DC = computeDeclContext(*SS, EnteringContext)) { 1617 // We have resolved the scope specifier to a particular declaration 1618 // contex, and will perform name lookup in that context. 1619 if (!DC->isDependentContext() && RequireCompleteDeclContext(*SS, DC)) 1620 return false; 1621 1622 R.setContextRange(SS->getRange()); 1623 return LookupQualifiedName(R, DC); 1624 } 1625 1626 // We could not resolve the scope specified to a specific declaration 1627 // context, which means that SS refers to an unknown specialization. 1628 // Name lookup can't find anything in this case. 1629 R.setNotFoundInCurrentInstantiation(); 1630 R.setContextRange(SS->getRange()); 1631 return false; 1632 } 1633 1634 // Perform unqualified name lookup starting in the given scope. 1635 return LookupName(R, S, AllowBuiltinCreation); 1636 } 1637 1638 1639 /// @brief Produce a diagnostic describing the ambiguity that resulted 1640 /// from name lookup. 1641 /// 1642 /// @param Result The ambiguous name lookup result. 1643 /// 1644 /// @param Name The name of the entity that name lookup was 1645 /// searching for. 1646 /// 1647 /// @param NameLoc The location of the name within the source code. 1648 /// 1649 /// @param LookupRange A source range that provides more 1650 /// source-location information concerning the lookup itself. For 1651 /// example, this range might highlight a nested-name-specifier that 1652 /// precedes the name. 1653 /// 1654 /// @returns true 1655 bool Sema::DiagnoseAmbiguousLookup(LookupResult &Result) { 1656 assert(Result.isAmbiguous() && "Lookup result must be ambiguous"); 1657 1658 DeclarationName Name = Result.getLookupName(); 1659 SourceLocation NameLoc = Result.getNameLoc(); 1660 SourceRange LookupRange = Result.getContextRange(); 1661 1662 switch (Result.getAmbiguityKind()) { 1663 case LookupResult::AmbiguousBaseSubobjects: { 1664 CXXBasePaths *Paths = Result.getBasePaths(); 1665 QualType SubobjectType = Paths->front().back().Base->getType(); 1666 Diag(NameLoc, diag::err_ambiguous_member_multiple_subobjects) 1667 << Name << SubobjectType << getAmbiguousPathsDisplayString(*Paths) 1668 << LookupRange; 1669 1670 DeclContext::lookup_iterator Found = Paths->front().Decls.first; 1671 while (isa<CXXMethodDecl>(*Found) && 1672 cast<CXXMethodDecl>(*Found)->isStatic()) 1673 ++Found; 1674 1675 Diag((*Found)->getLocation(), diag::note_ambiguous_member_found); 1676 1677 return true; 1678 } 1679 1680 case LookupResult::AmbiguousBaseSubobjectTypes: { 1681 Diag(NameLoc, diag::err_ambiguous_member_multiple_subobject_types) 1682 << Name << LookupRange; 1683 1684 CXXBasePaths *Paths = Result.getBasePaths(); 1685 std::set<Decl *> DeclsPrinted; 1686 for (CXXBasePaths::paths_iterator Path = Paths->begin(), 1687 PathEnd = Paths->end(); 1688 Path != PathEnd; ++Path) { 1689 Decl *D = *Path->Decls.first; 1690 if (DeclsPrinted.insert(D).second) 1691 Diag(D->getLocation(), diag::note_ambiguous_member_found); 1692 } 1693 1694 return true; 1695 } 1696 1697 case LookupResult::AmbiguousTagHiding: { 1698 Diag(NameLoc, diag::err_ambiguous_tag_hiding) << Name << LookupRange; 1699 1700 llvm::SmallPtrSet<NamedDecl*,8> TagDecls; 1701 1702 LookupResult::iterator DI, DE = Result.end(); 1703 for (DI = Result.begin(); DI != DE; ++DI) 1704 if (TagDecl *TD = dyn_cast<TagDecl>(*DI)) { 1705 TagDecls.insert(TD); 1706 Diag(TD->getLocation(), diag::note_hidden_tag); 1707 } 1708 1709 for (DI = Result.begin(); DI != DE; ++DI) 1710 if (!isa<TagDecl>(*DI)) 1711 Diag((*DI)->getLocation(), diag::note_hiding_object); 1712 1713 // For recovery purposes, go ahead and implement the hiding. 1714 LookupResult::Filter F = Result.makeFilter(); 1715 while (F.hasNext()) { 1716 if (TagDecls.count(F.next())) 1717 F.erase(); 1718 } 1719 F.done(); 1720 1721 return true; 1722 } 1723 1724 case LookupResult::AmbiguousReference: { 1725 Diag(NameLoc, diag::err_ambiguous_reference) << Name << LookupRange; 1726 1727 LookupResult::iterator DI = Result.begin(), DE = Result.end(); 1728 for (; DI != DE; ++DI) 1729 Diag((*DI)->getLocation(), diag::note_ambiguous_candidate) << *DI; 1730 1731 return true; 1732 } 1733 } 1734 1735 llvm_unreachable("unknown ambiguity kind"); 1736 } 1737 1738 namespace { 1739 struct AssociatedLookup { 1740 AssociatedLookup(Sema &S, 1741 Sema::AssociatedNamespaceSet &Namespaces, 1742 Sema::AssociatedClassSet &Classes) 1743 : S(S), Namespaces(Namespaces), Classes(Classes) { 1744 } 1745 1746 Sema &S; 1747 Sema::AssociatedNamespaceSet &Namespaces; 1748 Sema::AssociatedClassSet &Classes; 1749 }; 1750 } 1751 1752 static void 1753 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType T); 1754 1755 static void CollectEnclosingNamespace(Sema::AssociatedNamespaceSet &Namespaces, 1756 DeclContext *Ctx) { 1757 // Add the associated namespace for this class. 1758 1759 // We don't use DeclContext::getEnclosingNamespaceContext() as this may 1760 // be a locally scoped record. 1761 1762 // We skip out of inline namespaces. The innermost non-inline namespace 1763 // contains all names of all its nested inline namespaces anyway, so we can 1764 // replace the entire inline namespace tree with its root. 1765 while (Ctx->isRecord() || Ctx->isTransparentContext() || 1766 Ctx->isInlineNamespace()) 1767 Ctx = Ctx->getParent(); 1768 1769 if (Ctx->isFileContext()) 1770 Namespaces.insert(Ctx->getPrimaryContext()); 1771 } 1772 1773 // \brief Add the associated classes and namespaces for argument-dependent 1774 // lookup that involves a template argument (C++ [basic.lookup.koenig]p2). 1775 static void 1776 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, 1777 const TemplateArgument &Arg) { 1778 // C++ [basic.lookup.koenig]p2, last bullet: 1779 // -- [...] ; 1780 switch (Arg.getKind()) { 1781 case TemplateArgument::Null: 1782 break; 1783 1784 case TemplateArgument::Type: 1785 // [...] the namespaces and classes associated with the types of the 1786 // template arguments provided for template type parameters (excluding 1787 // template template parameters) 1788 addAssociatedClassesAndNamespaces(Result, Arg.getAsType()); 1789 break; 1790 1791 case TemplateArgument::Template: 1792 case TemplateArgument::TemplateExpansion: { 1793 // [...] the namespaces in which any template template arguments are 1794 // defined; and the classes in which any member templates used as 1795 // template template arguments are defined. 1796 TemplateName Template = Arg.getAsTemplateOrTemplatePattern(); 1797 if (ClassTemplateDecl *ClassTemplate 1798 = dyn_cast<ClassTemplateDecl>(Template.getAsTemplateDecl())) { 1799 DeclContext *Ctx = ClassTemplate->getDeclContext(); 1800 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx)) 1801 Result.Classes.insert(EnclosingClass); 1802 // Add the associated namespace for this class. 1803 CollectEnclosingNamespace(Result.Namespaces, Ctx); 1804 } 1805 break; 1806 } 1807 1808 case TemplateArgument::Declaration: 1809 case TemplateArgument::Integral: 1810 case TemplateArgument::Expression: 1811 // [Note: non-type template arguments do not contribute to the set of 1812 // associated namespaces. ] 1813 break; 1814 1815 case TemplateArgument::Pack: 1816 for (TemplateArgument::pack_iterator P = Arg.pack_begin(), 1817 PEnd = Arg.pack_end(); 1818 P != PEnd; ++P) 1819 addAssociatedClassesAndNamespaces(Result, *P); 1820 break; 1821 } 1822 } 1823 1824 // \brief Add the associated classes and namespaces for 1825 // argument-dependent lookup with an argument of class type 1826 // (C++ [basic.lookup.koenig]p2). 1827 static void 1828 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, 1829 CXXRecordDecl *Class) { 1830 1831 // Just silently ignore anything whose name is __va_list_tag. 1832 if (Class->getDeclName() == Result.S.VAListTagName) 1833 return; 1834 1835 // C++ [basic.lookup.koenig]p2: 1836 // [...] 1837 // -- If T is a class type (including unions), its associated 1838 // classes are: the class itself; the class of which it is a 1839 // member, if any; and its direct and indirect base 1840 // classes. Its associated namespaces are the namespaces in 1841 // which its associated classes are defined. 1842 1843 // Add the class of which it is a member, if any. 1844 DeclContext *Ctx = Class->getDeclContext(); 1845 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx)) 1846 Result.Classes.insert(EnclosingClass); 1847 // Add the associated namespace for this class. 1848 CollectEnclosingNamespace(Result.Namespaces, Ctx); 1849 1850 // Add the class itself. If we've already seen this class, we don't 1851 // need to visit base classes. 1852 if (!Result.Classes.insert(Class)) 1853 return; 1854 1855 // -- If T is a template-id, its associated namespaces and classes are 1856 // the namespace in which the template is defined; for member 1857 // templates, the member template's class; the namespaces and classes 1858 // associated with the types of the template arguments provided for 1859 // template type parameters (excluding template template parameters); the 1860 // namespaces in which any template template arguments are defined; and 1861 // the classes in which any member templates used as template template 1862 // arguments are defined. [Note: non-type template arguments do not 1863 // contribute to the set of associated namespaces. ] 1864 if (ClassTemplateSpecializationDecl *Spec 1865 = dyn_cast<ClassTemplateSpecializationDecl>(Class)) { 1866 DeclContext *Ctx = Spec->getSpecializedTemplate()->getDeclContext(); 1867 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx)) 1868 Result.Classes.insert(EnclosingClass); 1869 // Add the associated namespace for this class. 1870 CollectEnclosingNamespace(Result.Namespaces, Ctx); 1871 1872 const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs(); 1873 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I) 1874 addAssociatedClassesAndNamespaces(Result, TemplateArgs[I]); 1875 } 1876 1877 // Only recurse into base classes for complete types. 1878 if (!Class->hasDefinition()) { 1879 // FIXME: we might need to instantiate templates here 1880 return; 1881 } 1882 1883 // Add direct and indirect base classes along with their associated 1884 // namespaces. 1885 SmallVector<CXXRecordDecl *, 32> Bases; 1886 Bases.push_back(Class); 1887 while (!Bases.empty()) { 1888 // Pop this class off the stack. 1889 Class = Bases.back(); 1890 Bases.pop_back(); 1891 1892 // Visit the base classes. 1893 for (CXXRecordDecl::base_class_iterator Base = Class->bases_begin(), 1894 BaseEnd = Class->bases_end(); 1895 Base != BaseEnd; ++Base) { 1896 const RecordType *BaseType = Base->getType()->getAs<RecordType>(); 1897 // In dependent contexts, we do ADL twice, and the first time around, 1898 // the base type might be a dependent TemplateSpecializationType, or a 1899 // TemplateTypeParmType. If that happens, simply ignore it. 1900 // FIXME: If we want to support export, we probably need to add the 1901 // namespace of the template in a TemplateSpecializationType, or even 1902 // the classes and namespaces of known non-dependent arguments. 1903 if (!BaseType) 1904 continue; 1905 CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(BaseType->getDecl()); 1906 if (Result.Classes.insert(BaseDecl)) { 1907 // Find the associated namespace for this base class. 1908 DeclContext *BaseCtx = BaseDecl->getDeclContext(); 1909 CollectEnclosingNamespace(Result.Namespaces, BaseCtx); 1910 1911 // Make sure we visit the bases of this base class. 1912 if (BaseDecl->bases_begin() != BaseDecl->bases_end()) 1913 Bases.push_back(BaseDecl); 1914 } 1915 } 1916 } 1917 } 1918 1919 // \brief Add the associated classes and namespaces for 1920 // argument-dependent lookup with an argument of type T 1921 // (C++ [basic.lookup.koenig]p2). 1922 static void 1923 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType Ty) { 1924 // C++ [basic.lookup.koenig]p2: 1925 // 1926 // For each argument type T in the function call, there is a set 1927 // of zero or more associated namespaces and a set of zero or more 1928 // associated classes to be considered. The sets of namespaces and 1929 // classes is determined entirely by the types of the function 1930 // arguments (and the namespace of any template template 1931 // argument). Typedef names and using-declarations used to specify 1932 // the types do not contribute to this set. The sets of namespaces 1933 // and classes are determined in the following way: 1934 1935 SmallVector<const Type *, 16> Queue; 1936 const Type *T = Ty->getCanonicalTypeInternal().getTypePtr(); 1937 1938 while (true) { 1939 switch (T->getTypeClass()) { 1940 1941 #define TYPE(Class, Base) 1942 #define DEPENDENT_TYPE(Class, Base) case Type::Class: 1943 #define NON_CANONICAL_TYPE(Class, Base) case Type::Class: 1944 #define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class: 1945 #define ABSTRACT_TYPE(Class, Base) 1946 #include "clang/AST/TypeNodes.def" 1947 // T is canonical. We can also ignore dependent types because 1948 // we don't need to do ADL at the definition point, but if we 1949 // wanted to implement template export (or if we find some other 1950 // use for associated classes and namespaces...) this would be 1951 // wrong. 1952 break; 1953 1954 // -- If T is a pointer to U or an array of U, its associated 1955 // namespaces and classes are those associated with U. 1956 case Type::Pointer: 1957 T = cast<PointerType>(T)->getPointeeType().getTypePtr(); 1958 continue; 1959 case Type::ConstantArray: 1960 case Type::IncompleteArray: 1961 case Type::VariableArray: 1962 T = cast<ArrayType>(T)->getElementType().getTypePtr(); 1963 continue; 1964 1965 // -- If T is a fundamental type, its associated sets of 1966 // namespaces and classes are both empty. 1967 case Type::Builtin: 1968 break; 1969 1970 // -- If T is a class type (including unions), its associated 1971 // classes are: the class itself; the class of which it is a 1972 // member, if any; and its direct and indirect base 1973 // classes. Its associated namespaces are the namespaces in 1974 // which its associated classes are defined. 1975 case Type::Record: { 1976 CXXRecordDecl *Class 1977 = cast<CXXRecordDecl>(cast<RecordType>(T)->getDecl()); 1978 addAssociatedClassesAndNamespaces(Result, Class); 1979 break; 1980 } 1981 1982 // -- If T is an enumeration type, its associated namespace is 1983 // the namespace in which it is defined. If it is class 1984 // member, its associated class is the member's class; else 1985 // it has no associated class. 1986 case Type::Enum: { 1987 EnumDecl *Enum = cast<EnumType>(T)->getDecl(); 1988 1989 DeclContext *Ctx = Enum->getDeclContext(); 1990 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx)) 1991 Result.Classes.insert(EnclosingClass); 1992 1993 // Add the associated namespace for this class. 1994 CollectEnclosingNamespace(Result.Namespaces, Ctx); 1995 1996 break; 1997 } 1998 1999 // -- If T is a function type, its associated namespaces and 2000 // classes are those associated with the function parameter 2001 // types and those associated with the return type. 2002 case Type::FunctionProto: { 2003 const FunctionProtoType *Proto = cast<FunctionProtoType>(T); 2004 for (FunctionProtoType::arg_type_iterator Arg = Proto->arg_type_begin(), 2005 ArgEnd = Proto->arg_type_end(); 2006 Arg != ArgEnd; ++Arg) 2007 Queue.push_back(Arg->getTypePtr()); 2008 // fallthrough 2009 } 2010 case Type::FunctionNoProto: { 2011 const FunctionType *FnType = cast<FunctionType>(T); 2012 T = FnType->getResultType().getTypePtr(); 2013 continue; 2014 } 2015 2016 // -- If T is a pointer to a member function of a class X, its 2017 // associated namespaces and classes are those associated 2018 // with the function parameter types and return type, 2019 // together with those associated with X. 2020 // 2021 // -- If T is a pointer to a data member of class X, its 2022 // associated namespaces and classes are those associated 2023 // with the member type together with those associated with 2024 // X. 2025 case Type::MemberPointer: { 2026 const MemberPointerType *MemberPtr = cast<MemberPointerType>(T); 2027 2028 // Queue up the class type into which this points. 2029 Queue.push_back(MemberPtr->getClass()); 2030 2031 // And directly continue with the pointee type. 2032 T = MemberPtr->getPointeeType().getTypePtr(); 2033 continue; 2034 } 2035 2036 // As an extension, treat this like a normal pointer. 2037 case Type::BlockPointer: 2038 T = cast<BlockPointerType>(T)->getPointeeType().getTypePtr(); 2039 continue; 2040 2041 // References aren't covered by the standard, but that's such an 2042 // obvious defect that we cover them anyway. 2043 case Type::LValueReference: 2044 case Type::RValueReference: 2045 T = cast<ReferenceType>(T)->getPointeeType().getTypePtr(); 2046 continue; 2047 2048 // These are fundamental types. 2049 case Type::Vector: 2050 case Type::ExtVector: 2051 case Type::Complex: 2052 break; 2053 2054 // If T is an Objective-C object or interface type, or a pointer to an 2055 // object or interface type, the associated namespace is the global 2056 // namespace. 2057 case Type::ObjCObject: 2058 case Type::ObjCInterface: 2059 case Type::ObjCObjectPointer: 2060 Result.Namespaces.insert(Result.S.Context.getTranslationUnitDecl()); 2061 break; 2062 2063 // Atomic types are just wrappers; use the associations of the 2064 // contained type. 2065 case Type::Atomic: 2066 T = cast<AtomicType>(T)->getValueType().getTypePtr(); 2067 continue; 2068 } 2069 2070 if (Queue.empty()) break; 2071 T = Queue.back(); 2072 Queue.pop_back(); 2073 } 2074 } 2075 2076 /// \brief Find the associated classes and namespaces for 2077 /// argument-dependent lookup for a call with the given set of 2078 /// arguments. 2079 /// 2080 /// This routine computes the sets of associated classes and associated 2081 /// namespaces searched by argument-dependent lookup 2082 /// (C++ [basic.lookup.argdep]) for a given set of arguments. 2083 void 2084 Sema::FindAssociatedClassesAndNamespaces(llvm::ArrayRef<Expr *> Args, 2085 AssociatedNamespaceSet &AssociatedNamespaces, 2086 AssociatedClassSet &AssociatedClasses) { 2087 AssociatedNamespaces.clear(); 2088 AssociatedClasses.clear(); 2089 2090 AssociatedLookup Result(*this, AssociatedNamespaces, AssociatedClasses); 2091 2092 // C++ [basic.lookup.koenig]p2: 2093 // For each argument type T in the function call, there is a set 2094 // of zero or more associated namespaces and a set of zero or more 2095 // associated classes to be considered. The sets of namespaces and 2096 // classes is determined entirely by the types of the function 2097 // arguments (and the namespace of any template template 2098 // argument). 2099 for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) { 2100 Expr *Arg = Args[ArgIdx]; 2101 2102 if (Arg->getType() != Context.OverloadTy) { 2103 addAssociatedClassesAndNamespaces(Result, Arg->getType()); 2104 continue; 2105 } 2106 2107 // [...] In addition, if the argument is the name or address of a 2108 // set of overloaded functions and/or function templates, its 2109 // associated classes and namespaces are the union of those 2110 // associated with each of the members of the set: the namespace 2111 // in which the function or function template is defined and the 2112 // classes and namespaces associated with its (non-dependent) 2113 // parameter types and return type. 2114 Arg = Arg->IgnoreParens(); 2115 if (UnaryOperator *unaryOp = dyn_cast<UnaryOperator>(Arg)) 2116 if (unaryOp->getOpcode() == UO_AddrOf) 2117 Arg = unaryOp->getSubExpr(); 2118 2119 UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Arg); 2120 if (!ULE) continue; 2121 2122 for (UnresolvedSetIterator I = ULE->decls_begin(), E = ULE->decls_end(); 2123 I != E; ++I) { 2124 // Look through any using declarations to find the underlying function. 2125 NamedDecl *Fn = (*I)->getUnderlyingDecl(); 2126 2127 FunctionDecl *FDecl = dyn_cast<FunctionDecl>(Fn); 2128 if (!FDecl) 2129 FDecl = cast<FunctionTemplateDecl>(Fn)->getTemplatedDecl(); 2130 2131 // Add the classes and namespaces associated with the parameter 2132 // types and return type of this function. 2133 addAssociatedClassesAndNamespaces(Result, FDecl->getType()); 2134 } 2135 } 2136 } 2137 2138 /// IsAcceptableNonMemberOperatorCandidate - Determine whether Fn is 2139 /// an acceptable non-member overloaded operator for a call whose 2140 /// arguments have types T1 (and, if non-empty, T2). This routine 2141 /// implements the check in C++ [over.match.oper]p3b2 concerning 2142 /// enumeration types. 2143 static bool 2144 IsAcceptableNonMemberOperatorCandidate(FunctionDecl *Fn, 2145 QualType T1, QualType T2, 2146 ASTContext &Context) { 2147 if (T1->isDependentType() || (!T2.isNull() && T2->isDependentType())) 2148 return true; 2149 2150 if (T1->isRecordType() || (!T2.isNull() && T2->isRecordType())) 2151 return true; 2152 2153 const FunctionProtoType *Proto = Fn->getType()->getAs<FunctionProtoType>(); 2154 if (Proto->getNumArgs() < 1) 2155 return false; 2156 2157 if (T1->isEnumeralType()) { 2158 QualType ArgType = Proto->getArgType(0).getNonReferenceType(); 2159 if (Context.hasSameUnqualifiedType(T1, ArgType)) 2160 return true; 2161 } 2162 2163 if (Proto->getNumArgs() < 2) 2164 return false; 2165 2166 if (!T2.isNull() && T2->isEnumeralType()) { 2167 QualType ArgType = Proto->getArgType(1).getNonReferenceType(); 2168 if (Context.hasSameUnqualifiedType(T2, ArgType)) 2169 return true; 2170 } 2171 2172 return false; 2173 } 2174 2175 NamedDecl *Sema::LookupSingleName(Scope *S, DeclarationName Name, 2176 SourceLocation Loc, 2177 LookupNameKind NameKind, 2178 RedeclarationKind Redecl) { 2179 LookupResult R(*this, Name, Loc, NameKind, Redecl); 2180 LookupName(R, S); 2181 return R.getAsSingle<NamedDecl>(); 2182 } 2183 2184 /// \brief Find the protocol with the given name, if any. 2185 ObjCProtocolDecl *Sema::LookupProtocol(IdentifierInfo *II, 2186 SourceLocation IdLoc, 2187 RedeclarationKind Redecl) { 2188 Decl *D = LookupSingleName(TUScope, II, IdLoc, 2189 LookupObjCProtocolName, Redecl); 2190 return cast_or_null<ObjCProtocolDecl>(D); 2191 } 2192 2193 void Sema::LookupOverloadedOperatorName(OverloadedOperatorKind Op, Scope *S, 2194 QualType T1, QualType T2, 2195 UnresolvedSetImpl &Functions) { 2196 // C++ [over.match.oper]p3: 2197 // -- The set of non-member candidates is the result of the 2198 // unqualified lookup of operator@ in the context of the 2199 // expression according to the usual rules for name lookup in 2200 // unqualified function calls (3.4.2) except that all member 2201 // functions are ignored. However, if no operand has a class 2202 // type, only those non-member functions in the lookup set 2203 // that have a first parameter of type T1 or "reference to 2204 // (possibly cv-qualified) T1", when T1 is an enumeration 2205 // type, or (if there is a right operand) a second parameter 2206 // of type T2 or "reference to (possibly cv-qualified) T2", 2207 // when T2 is an enumeration type, are candidate functions. 2208 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 2209 LookupResult Operators(*this, OpName, SourceLocation(), LookupOperatorName); 2210 LookupName(Operators, S); 2211 2212 assert(!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous"); 2213 2214 if (Operators.empty()) 2215 return; 2216 2217 for (LookupResult::iterator Op = Operators.begin(), OpEnd = Operators.end(); 2218 Op != OpEnd; ++Op) { 2219 NamedDecl *Found = (*Op)->getUnderlyingDecl(); 2220 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Found)) { 2221 if (IsAcceptableNonMemberOperatorCandidate(FD, T1, T2, Context)) 2222 Functions.addDecl(*Op, Op.getAccess()); // FIXME: canonical FD 2223 } else if (FunctionTemplateDecl *FunTmpl 2224 = dyn_cast<FunctionTemplateDecl>(Found)) { 2225 // FIXME: friend operators? 2226 // FIXME: do we need to check IsAcceptableNonMemberOperatorCandidate, 2227 // later? 2228 if (!FunTmpl->getDeclContext()->isRecord()) 2229 Functions.addDecl(*Op, Op.getAccess()); 2230 } 2231 } 2232 } 2233 2234 Sema::SpecialMemberOverloadResult *Sema::LookupSpecialMember(CXXRecordDecl *RD, 2235 CXXSpecialMember SM, 2236 bool ConstArg, 2237 bool VolatileArg, 2238 bool RValueThis, 2239 bool ConstThis, 2240 bool VolatileThis) { 2241 RD = RD->getDefinition(); 2242 assert((RD && !RD->isBeingDefined()) && 2243 "doing special member lookup into record that isn't fully complete"); 2244 if (RValueThis || ConstThis || VolatileThis) 2245 assert((SM == CXXCopyAssignment || SM == CXXMoveAssignment) && 2246 "constructors and destructors always have unqualified lvalue this"); 2247 if (ConstArg || VolatileArg) 2248 assert((SM != CXXDefaultConstructor && SM != CXXDestructor) && 2249 "parameter-less special members can't have qualified arguments"); 2250 2251 llvm::FoldingSetNodeID ID; 2252 ID.AddPointer(RD); 2253 ID.AddInteger(SM); 2254 ID.AddInteger(ConstArg); 2255 ID.AddInteger(VolatileArg); 2256 ID.AddInteger(RValueThis); 2257 ID.AddInteger(ConstThis); 2258 ID.AddInteger(VolatileThis); 2259 2260 void *InsertPoint; 2261 SpecialMemberOverloadResult *Result = 2262 SpecialMemberCache.FindNodeOrInsertPos(ID, InsertPoint); 2263 2264 // This was already cached 2265 if (Result) 2266 return Result; 2267 2268 Result = BumpAlloc.Allocate<SpecialMemberOverloadResult>(); 2269 Result = new (Result) SpecialMemberOverloadResult(ID); 2270 SpecialMemberCache.InsertNode(Result, InsertPoint); 2271 2272 if (SM == CXXDestructor) { 2273 if (!RD->hasDeclaredDestructor()) 2274 DeclareImplicitDestructor(RD); 2275 CXXDestructorDecl *DD = RD->getDestructor(); 2276 assert(DD && "record without a destructor"); 2277 Result->setMethod(DD); 2278 Result->setKind(DD->isDeleted() ? 2279 SpecialMemberOverloadResult::NoMemberOrDeleted : 2280 SpecialMemberOverloadResult::SuccessNonConst); 2281 return Result; 2282 } 2283 2284 // Prepare for overload resolution. Here we construct a synthetic argument 2285 // if necessary and make sure that implicit functions are declared. 2286 CanQualType CanTy = Context.getCanonicalType(Context.getTagDeclType(RD)); 2287 DeclarationName Name; 2288 Expr *Arg = 0; 2289 unsigned NumArgs; 2290 2291 if (SM == CXXDefaultConstructor) { 2292 Name = Context.DeclarationNames.getCXXConstructorName(CanTy); 2293 NumArgs = 0; 2294 if (RD->needsImplicitDefaultConstructor()) 2295 DeclareImplicitDefaultConstructor(RD); 2296 } else { 2297 if (SM == CXXCopyConstructor || SM == CXXMoveConstructor) { 2298 Name = Context.DeclarationNames.getCXXConstructorName(CanTy); 2299 if (!RD->hasDeclaredCopyConstructor()) 2300 DeclareImplicitCopyConstructor(RD); 2301 if (getLangOpts().CPlusPlus0x && RD->needsImplicitMoveConstructor()) 2302 DeclareImplicitMoveConstructor(RD); 2303 } else { 2304 Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal); 2305 if (!RD->hasDeclaredCopyAssignment()) 2306 DeclareImplicitCopyAssignment(RD); 2307 if (getLangOpts().CPlusPlus0x && RD->needsImplicitMoveAssignment()) 2308 DeclareImplicitMoveAssignment(RD); 2309 } 2310 2311 QualType ArgType = CanTy; 2312 if (ConstArg) 2313 ArgType.addConst(); 2314 if (VolatileArg) 2315 ArgType.addVolatile(); 2316 2317 // This isn't /really/ specified by the standard, but it's implied 2318 // we should be working from an RValue in the case of move to ensure 2319 // that we prefer to bind to rvalue references, and an LValue in the 2320 // case of copy to ensure we don't bind to rvalue references. 2321 // Possibly an XValue is actually correct in the case of move, but 2322 // there is no semantic difference for class types in this restricted 2323 // case. 2324 ExprValueKind VK; 2325 if (SM == CXXCopyConstructor || SM == CXXCopyAssignment) 2326 VK = VK_LValue; 2327 else 2328 VK = VK_RValue; 2329 2330 NumArgs = 1; 2331 Arg = new (Context) OpaqueValueExpr(SourceLocation(), ArgType, VK); 2332 } 2333 2334 // Create the object argument 2335 QualType ThisTy = CanTy; 2336 if (ConstThis) 2337 ThisTy.addConst(); 2338 if (VolatileThis) 2339 ThisTy.addVolatile(); 2340 Expr::Classification Classification = 2341 (new (Context) OpaqueValueExpr(SourceLocation(), ThisTy, 2342 RValueThis ? VK_RValue : VK_LValue))-> 2343 Classify(Context); 2344 2345 // Now we perform lookup on the name we computed earlier and do overload 2346 // resolution. Lookup is only performed directly into the class since there 2347 // will always be a (possibly implicit) declaration to shadow any others. 2348 OverloadCandidateSet OCS((SourceLocation())); 2349 DeclContext::lookup_iterator I, E; 2350 SpecialMemberOverloadResult::Kind SuccessKind = 2351 SpecialMemberOverloadResult::SuccessNonConst; 2352 2353 llvm::tie(I, E) = RD->lookup(Name); 2354 assert((I != E) && 2355 "lookup for a constructor or assignment operator was empty"); 2356 for ( ; I != E; ++I) { 2357 Decl *Cand = *I; 2358 2359 if (Cand->isInvalidDecl()) 2360 continue; 2361 2362 if (UsingShadowDecl *U = dyn_cast<UsingShadowDecl>(Cand)) { 2363 // FIXME: [namespace.udecl]p15 says that we should only consider a 2364 // using declaration here if it does not match a declaration in the 2365 // derived class. We do not implement this correctly in other cases 2366 // either. 2367 Cand = U->getTargetDecl(); 2368 2369 if (Cand->isInvalidDecl()) 2370 continue; 2371 } 2372 2373 if (CXXMethodDecl *M = dyn_cast<CXXMethodDecl>(Cand)) { 2374 if (SM == CXXCopyAssignment || SM == CXXMoveAssignment) 2375 AddMethodCandidate(M, DeclAccessPair::make(M, AS_public), RD, ThisTy, 2376 Classification, llvm::makeArrayRef(&Arg, NumArgs), 2377 OCS, true); 2378 else 2379 AddOverloadCandidate(M, DeclAccessPair::make(M, AS_public), 2380 llvm::makeArrayRef(&Arg, NumArgs), OCS, true); 2381 2382 // Here we're looking for a const parameter to speed up creation of 2383 // implicit copy methods. 2384 if ((SM == CXXCopyAssignment && M->isCopyAssignmentOperator()) || 2385 (SM == CXXCopyConstructor && 2386 cast<CXXConstructorDecl>(M)->isCopyConstructor())) { 2387 QualType ArgType = M->getType()->getAs<FunctionProtoType>()->getArgType(0); 2388 if (!ArgType->isReferenceType() || 2389 ArgType->getPointeeType().isConstQualified()) 2390 SuccessKind = SpecialMemberOverloadResult::SuccessConst; 2391 } 2392 } else if (FunctionTemplateDecl *Tmpl = 2393 dyn_cast<FunctionTemplateDecl>(Cand)) { 2394 if (SM == CXXCopyAssignment || SM == CXXMoveAssignment) 2395 AddMethodTemplateCandidate(Tmpl, DeclAccessPair::make(Tmpl, AS_public), 2396 RD, 0, ThisTy, Classification, 2397 llvm::makeArrayRef(&Arg, NumArgs), 2398 OCS, true); 2399 else 2400 AddTemplateOverloadCandidate(Tmpl, DeclAccessPair::make(Tmpl, AS_public), 2401 0, llvm::makeArrayRef(&Arg, NumArgs), 2402 OCS, true); 2403 } else { 2404 assert(isa<UsingDecl>(Cand) && "illegal Kind of operator = Decl"); 2405 } 2406 } 2407 2408 OverloadCandidateSet::iterator Best; 2409 switch (OCS.BestViableFunction(*this, SourceLocation(), Best)) { 2410 case OR_Success: 2411 Result->setMethod(cast<CXXMethodDecl>(Best->Function)); 2412 Result->setKind(SuccessKind); 2413 break; 2414 2415 case OR_Deleted: 2416 Result->setMethod(cast<CXXMethodDecl>(Best->Function)); 2417 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted); 2418 break; 2419 2420 case OR_Ambiguous: 2421 Result->setMethod(0); 2422 Result->setKind(SpecialMemberOverloadResult::Ambiguous); 2423 break; 2424 2425 case OR_No_Viable_Function: 2426 Result->setMethod(0); 2427 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted); 2428 break; 2429 } 2430 2431 return Result; 2432 } 2433 2434 /// \brief Look up the default constructor for the given class. 2435 CXXConstructorDecl *Sema::LookupDefaultConstructor(CXXRecordDecl *Class) { 2436 SpecialMemberOverloadResult *Result = 2437 LookupSpecialMember(Class, CXXDefaultConstructor, false, false, false, 2438 false, false); 2439 2440 return cast_or_null<CXXConstructorDecl>(Result->getMethod()); 2441 } 2442 2443 /// \brief Look up the copying constructor for the given class. 2444 CXXConstructorDecl *Sema::LookupCopyingConstructor(CXXRecordDecl *Class, 2445 unsigned Quals, 2446 bool *ConstParamMatch) { 2447 assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) && 2448 "non-const, non-volatile qualifiers for copy ctor arg"); 2449 SpecialMemberOverloadResult *Result = 2450 LookupSpecialMember(Class, CXXCopyConstructor, Quals & Qualifiers::Const, 2451 Quals & Qualifiers::Volatile, false, false, false); 2452 2453 if (ConstParamMatch) 2454 *ConstParamMatch = Result->hasConstParamMatch(); 2455 2456 return cast_or_null<CXXConstructorDecl>(Result->getMethod()); 2457 } 2458 2459 /// \brief Look up the moving constructor for the given class. 2460 CXXConstructorDecl *Sema::LookupMovingConstructor(CXXRecordDecl *Class) { 2461 SpecialMemberOverloadResult *Result = 2462 LookupSpecialMember(Class, CXXMoveConstructor, false, 2463 false, false, false, false); 2464 2465 return cast_or_null<CXXConstructorDecl>(Result->getMethod()); 2466 } 2467 2468 /// \brief Look up the constructors for the given class. 2469 DeclContext::lookup_result Sema::LookupConstructors(CXXRecordDecl *Class) { 2470 // If the implicit constructors have not yet been declared, do so now. 2471 if (CanDeclareSpecialMemberFunction(Context, Class)) { 2472 if (Class->needsImplicitDefaultConstructor()) 2473 DeclareImplicitDefaultConstructor(Class); 2474 if (!Class->hasDeclaredCopyConstructor()) 2475 DeclareImplicitCopyConstructor(Class); 2476 if (getLangOpts().CPlusPlus0x && Class->needsImplicitMoveConstructor()) 2477 DeclareImplicitMoveConstructor(Class); 2478 } 2479 2480 CanQualType T = Context.getCanonicalType(Context.getTypeDeclType(Class)); 2481 DeclarationName Name = Context.DeclarationNames.getCXXConstructorName(T); 2482 return Class->lookup(Name); 2483 } 2484 2485 /// \brief Look up the copying assignment operator for the given class. 2486 CXXMethodDecl *Sema::LookupCopyingAssignment(CXXRecordDecl *Class, 2487 unsigned Quals, bool RValueThis, 2488 unsigned ThisQuals, 2489 bool *ConstParamMatch) { 2490 assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) && 2491 "non-const, non-volatile qualifiers for copy assignment arg"); 2492 assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) && 2493 "non-const, non-volatile qualifiers for copy assignment this"); 2494 SpecialMemberOverloadResult *Result = 2495 LookupSpecialMember(Class, CXXCopyAssignment, Quals & Qualifiers::Const, 2496 Quals & Qualifiers::Volatile, RValueThis, 2497 ThisQuals & Qualifiers::Const, 2498 ThisQuals & Qualifiers::Volatile); 2499 2500 if (ConstParamMatch) 2501 *ConstParamMatch = Result->hasConstParamMatch(); 2502 2503 return Result->getMethod(); 2504 } 2505 2506 /// \brief Look up the moving assignment operator for the given class. 2507 CXXMethodDecl *Sema::LookupMovingAssignment(CXXRecordDecl *Class, 2508 bool RValueThis, 2509 unsigned ThisQuals) { 2510 assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) && 2511 "non-const, non-volatile qualifiers for copy assignment this"); 2512 SpecialMemberOverloadResult *Result = 2513 LookupSpecialMember(Class, CXXMoveAssignment, false, false, RValueThis, 2514 ThisQuals & Qualifiers::Const, 2515 ThisQuals & Qualifiers::Volatile); 2516 2517 return Result->getMethod(); 2518 } 2519 2520 /// \brief Look for the destructor of the given class. 2521 /// 2522 /// During semantic analysis, this routine should be used in lieu of 2523 /// CXXRecordDecl::getDestructor(). 2524 /// 2525 /// \returns The destructor for this class. 2526 CXXDestructorDecl *Sema::LookupDestructor(CXXRecordDecl *Class) { 2527 return cast<CXXDestructorDecl>(LookupSpecialMember(Class, CXXDestructor, 2528 false, false, false, 2529 false, false)->getMethod()); 2530 } 2531 2532 /// LookupLiteralOperator - Determine which literal operator should be used for 2533 /// a user-defined literal, per C++11 [lex.ext]. 2534 /// 2535 /// Normal overload resolution is not used to select which literal operator to 2536 /// call for a user-defined literal. Look up the provided literal operator name, 2537 /// and filter the results to the appropriate set for the given argument types. 2538 Sema::LiteralOperatorLookupResult 2539 Sema::LookupLiteralOperator(Scope *S, LookupResult &R, 2540 ArrayRef<QualType> ArgTys, 2541 bool AllowRawAndTemplate) { 2542 LookupName(R, S); 2543 assert(R.getResultKind() != LookupResult::Ambiguous && 2544 "literal operator lookup can't be ambiguous"); 2545 2546 // Filter the lookup results appropriately. 2547 LookupResult::Filter F = R.makeFilter(); 2548 2549 bool FoundTemplate = false; 2550 bool FoundRaw = false; 2551 bool FoundExactMatch = false; 2552 2553 while (F.hasNext()) { 2554 Decl *D = F.next(); 2555 if (UsingShadowDecl *USD = dyn_cast<UsingShadowDecl>(D)) 2556 D = USD->getTargetDecl(); 2557 2558 bool IsTemplate = isa<FunctionTemplateDecl>(D); 2559 bool IsRaw = false; 2560 bool IsExactMatch = false; 2561 2562 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 2563 if (FD->getNumParams() == 1 && 2564 FD->getParamDecl(0)->getType()->getAs<PointerType>()) 2565 IsRaw = true; 2566 else { 2567 IsExactMatch = true; 2568 for (unsigned ArgIdx = 0; ArgIdx != ArgTys.size(); ++ArgIdx) { 2569 QualType ParamTy = FD->getParamDecl(ArgIdx)->getType(); 2570 if (!Context.hasSameUnqualifiedType(ArgTys[ArgIdx], ParamTy)) { 2571 IsExactMatch = false; 2572 break; 2573 } 2574 } 2575 } 2576 } 2577 2578 if (IsExactMatch) { 2579 FoundExactMatch = true; 2580 AllowRawAndTemplate = false; 2581 if (FoundRaw || FoundTemplate) { 2582 // Go through again and remove the raw and template decls we've 2583 // already found. 2584 F.restart(); 2585 FoundRaw = FoundTemplate = false; 2586 } 2587 } else if (AllowRawAndTemplate && (IsTemplate || IsRaw)) { 2588 FoundTemplate |= IsTemplate; 2589 FoundRaw |= IsRaw; 2590 } else { 2591 F.erase(); 2592 } 2593 } 2594 2595 F.done(); 2596 2597 // C++11 [lex.ext]p3, p4: If S contains a literal operator with a matching 2598 // parameter type, that is used in preference to a raw literal operator 2599 // or literal operator template. 2600 if (FoundExactMatch) 2601 return LOLR_Cooked; 2602 2603 // C++11 [lex.ext]p3, p4: S shall contain a raw literal operator or a literal 2604 // operator template, but not both. 2605 if (FoundRaw && FoundTemplate) { 2606 Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call) << R.getLookupName(); 2607 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2608 Decl *D = *I; 2609 if (UsingShadowDecl *USD = dyn_cast<UsingShadowDecl>(D)) 2610 D = USD->getTargetDecl(); 2611 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 2612 D = FunTmpl->getTemplatedDecl(); 2613 NoteOverloadCandidate(cast<FunctionDecl>(D)); 2614 } 2615 return LOLR_Error; 2616 } 2617 2618 if (FoundRaw) 2619 return LOLR_Raw; 2620 2621 if (FoundTemplate) 2622 return LOLR_Template; 2623 2624 // Didn't find anything we could use. 2625 Diag(R.getNameLoc(), diag::err_ovl_no_viable_literal_operator) 2626 << R.getLookupName() << (int)ArgTys.size() << ArgTys[0] 2627 << (ArgTys.size() == 2 ? ArgTys[1] : QualType()) << AllowRawAndTemplate; 2628 return LOLR_Error; 2629 } 2630 2631 void ADLResult::insert(NamedDecl *New) { 2632 NamedDecl *&Old = Decls[cast<NamedDecl>(New->getCanonicalDecl())]; 2633 2634 // If we haven't yet seen a decl for this key, or the last decl 2635 // was exactly this one, we're done. 2636 if (Old == 0 || Old == New) { 2637 Old = New; 2638 return; 2639 } 2640 2641 // Otherwise, decide which is a more recent redeclaration. 2642 FunctionDecl *OldFD, *NewFD; 2643 if (isa<FunctionTemplateDecl>(New)) { 2644 OldFD = cast<FunctionTemplateDecl>(Old)->getTemplatedDecl(); 2645 NewFD = cast<FunctionTemplateDecl>(New)->getTemplatedDecl(); 2646 } else { 2647 OldFD = cast<FunctionDecl>(Old); 2648 NewFD = cast<FunctionDecl>(New); 2649 } 2650 2651 FunctionDecl *Cursor = NewFD; 2652 while (true) { 2653 Cursor = Cursor->getPreviousDecl(); 2654 2655 // If we got to the end without finding OldFD, OldFD is the newer 2656 // declaration; leave things as they are. 2657 if (!Cursor) return; 2658 2659 // If we do find OldFD, then NewFD is newer. 2660 if (Cursor == OldFD) break; 2661 2662 // Otherwise, keep looking. 2663 } 2664 2665 Old = New; 2666 } 2667 2668 void Sema::ArgumentDependentLookup(DeclarationName Name, bool Operator, 2669 SourceLocation Loc, 2670 llvm::ArrayRef<Expr *> Args, 2671 ADLResult &Result, 2672 bool StdNamespaceIsAssociated) { 2673 // Find all of the associated namespaces and classes based on the 2674 // arguments we have. 2675 AssociatedNamespaceSet AssociatedNamespaces; 2676 AssociatedClassSet AssociatedClasses; 2677 FindAssociatedClassesAndNamespaces(Args, 2678 AssociatedNamespaces, 2679 AssociatedClasses); 2680 if (StdNamespaceIsAssociated && StdNamespace) 2681 AssociatedNamespaces.insert(getStdNamespace()); 2682 2683 QualType T1, T2; 2684 if (Operator) { 2685 T1 = Args[0]->getType(); 2686 if (Args.size() >= 2) 2687 T2 = Args[1]->getType(); 2688 } 2689 2690 // Try to complete all associated classes, in case they contain a 2691 // declaration of a friend function. 2692 for (AssociatedClassSet::iterator C = AssociatedClasses.begin(), 2693 CEnd = AssociatedClasses.end(); 2694 C != CEnd; ++C) 2695 RequireCompleteType(Loc, Context.getRecordType(*C), 0); 2696 2697 // C++ [basic.lookup.argdep]p3: 2698 // Let X be the lookup set produced by unqualified lookup (3.4.1) 2699 // and let Y be the lookup set produced by argument dependent 2700 // lookup (defined as follows). If X contains [...] then Y is 2701 // empty. Otherwise Y is the set of declarations found in the 2702 // namespaces associated with the argument types as described 2703 // below. The set of declarations found by the lookup of the name 2704 // is the union of X and Y. 2705 // 2706 // Here, we compute Y and add its members to the overloaded 2707 // candidate set. 2708 for (AssociatedNamespaceSet::iterator NS = AssociatedNamespaces.begin(), 2709 NSEnd = AssociatedNamespaces.end(); 2710 NS != NSEnd; ++NS) { 2711 // When considering an associated namespace, the lookup is the 2712 // same as the lookup performed when the associated namespace is 2713 // used as a qualifier (3.4.3.2) except that: 2714 // 2715 // -- Any using-directives in the associated namespace are 2716 // ignored. 2717 // 2718 // -- Any namespace-scope friend functions declared in 2719 // associated classes are visible within their respective 2720 // namespaces even if they are not visible during an ordinary 2721 // lookup (11.4). 2722 DeclContext::lookup_iterator I, E; 2723 for (llvm::tie(I, E) = (*NS)->lookup(Name); I != E; ++I) { 2724 NamedDecl *D = *I; 2725 // If the only declaration here is an ordinary friend, consider 2726 // it only if it was declared in an associated classes. 2727 if (D->getIdentifierNamespace() == Decl::IDNS_OrdinaryFriend) { 2728 DeclContext *LexDC = D->getLexicalDeclContext(); 2729 if (!AssociatedClasses.count(cast<CXXRecordDecl>(LexDC))) 2730 continue; 2731 } 2732 2733 if (isa<UsingShadowDecl>(D)) 2734 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2735 2736 if (isa<FunctionDecl>(D)) { 2737 if (Operator && 2738 !IsAcceptableNonMemberOperatorCandidate(cast<FunctionDecl>(D), 2739 T1, T2, Context)) 2740 continue; 2741 } else if (!isa<FunctionTemplateDecl>(D)) 2742 continue; 2743 2744 Result.insert(D); 2745 } 2746 } 2747 } 2748 2749 //---------------------------------------------------------------------------- 2750 // Search for all visible declarations. 2751 //---------------------------------------------------------------------------- 2752 VisibleDeclConsumer::~VisibleDeclConsumer() { } 2753 2754 namespace { 2755 2756 class ShadowContextRAII; 2757 2758 class VisibleDeclsRecord { 2759 public: 2760 /// \brief An entry in the shadow map, which is optimized to store a 2761 /// single declaration (the common case) but can also store a list 2762 /// of declarations. 2763 typedef llvm::TinyPtrVector<NamedDecl*> ShadowMapEntry; 2764 2765 private: 2766 /// \brief A mapping from declaration names to the declarations that have 2767 /// this name within a particular scope. 2768 typedef llvm::DenseMap<DeclarationName, ShadowMapEntry> ShadowMap; 2769 2770 /// \brief A list of shadow maps, which is used to model name hiding. 2771 std::list<ShadowMap> ShadowMaps; 2772 2773 /// \brief The declaration contexts we have already visited. 2774 llvm::SmallPtrSet<DeclContext *, 8> VisitedContexts; 2775 2776 friend class ShadowContextRAII; 2777 2778 public: 2779 /// \brief Determine whether we have already visited this context 2780 /// (and, if not, note that we are going to visit that context now). 2781 bool visitedContext(DeclContext *Ctx) { 2782 return !VisitedContexts.insert(Ctx); 2783 } 2784 2785 bool alreadyVisitedContext(DeclContext *Ctx) { 2786 return VisitedContexts.count(Ctx); 2787 } 2788 2789 /// \brief Determine whether the given declaration is hidden in the 2790 /// current scope. 2791 /// 2792 /// \returns the declaration that hides the given declaration, or 2793 /// NULL if no such declaration exists. 2794 NamedDecl *checkHidden(NamedDecl *ND); 2795 2796 /// \brief Add a declaration to the current shadow map. 2797 void add(NamedDecl *ND) { 2798 ShadowMaps.back()[ND->getDeclName()].push_back(ND); 2799 } 2800 }; 2801 2802 /// \brief RAII object that records when we've entered a shadow context. 2803 class ShadowContextRAII { 2804 VisibleDeclsRecord &Visible; 2805 2806 typedef VisibleDeclsRecord::ShadowMap ShadowMap; 2807 2808 public: 2809 ShadowContextRAII(VisibleDeclsRecord &Visible) : Visible(Visible) { 2810 Visible.ShadowMaps.push_back(ShadowMap()); 2811 } 2812 2813 ~ShadowContextRAII() { 2814 Visible.ShadowMaps.pop_back(); 2815 } 2816 }; 2817 2818 } // end anonymous namespace 2819 2820 NamedDecl *VisibleDeclsRecord::checkHidden(NamedDecl *ND) { 2821 // Look through using declarations. 2822 ND = ND->getUnderlyingDecl(); 2823 2824 unsigned IDNS = ND->getIdentifierNamespace(); 2825 std::list<ShadowMap>::reverse_iterator SM = ShadowMaps.rbegin(); 2826 for (std::list<ShadowMap>::reverse_iterator SMEnd = ShadowMaps.rend(); 2827 SM != SMEnd; ++SM) { 2828 ShadowMap::iterator Pos = SM->find(ND->getDeclName()); 2829 if (Pos == SM->end()) 2830 continue; 2831 2832 for (ShadowMapEntry::iterator I = Pos->second.begin(), 2833 IEnd = Pos->second.end(); 2834 I != IEnd; ++I) { 2835 // A tag declaration does not hide a non-tag declaration. 2836 if ((*I)->hasTagIdentifierNamespace() && 2837 (IDNS & (Decl::IDNS_Member | Decl::IDNS_Ordinary | 2838 Decl::IDNS_ObjCProtocol))) 2839 continue; 2840 2841 // Protocols are in distinct namespaces from everything else. 2842 if ((((*I)->getIdentifierNamespace() & Decl::IDNS_ObjCProtocol) 2843 || (IDNS & Decl::IDNS_ObjCProtocol)) && 2844 (*I)->getIdentifierNamespace() != IDNS) 2845 continue; 2846 2847 // Functions and function templates in the same scope overload 2848 // rather than hide. FIXME: Look for hiding based on function 2849 // signatures! 2850 if ((*I)->isFunctionOrFunctionTemplate() && 2851 ND->isFunctionOrFunctionTemplate() && 2852 SM == ShadowMaps.rbegin()) 2853 continue; 2854 2855 // We've found a declaration that hides this one. 2856 return *I; 2857 } 2858 } 2859 2860 return 0; 2861 } 2862 2863 static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result, 2864 bool QualifiedNameLookup, 2865 bool InBaseClass, 2866 VisibleDeclConsumer &Consumer, 2867 VisibleDeclsRecord &Visited) { 2868 if (!Ctx) 2869 return; 2870 2871 // Make sure we don't visit the same context twice. 2872 if (Visited.visitedContext(Ctx->getPrimaryContext())) 2873 return; 2874 2875 if (CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(Ctx)) 2876 Result.getSema().ForceDeclarationOfImplicitMembers(Class); 2877 2878 // Enumerate all of the results in this context. 2879 for (DeclContext::all_lookups_iterator L = Ctx->lookups_begin(), 2880 LEnd = Ctx->lookups_end(); 2881 L != LEnd; ++L) { 2882 for (DeclContext::lookup_result R = *L; R.first != R.second; ++R.first) { 2883 if (NamedDecl *ND = dyn_cast<NamedDecl>(*R.first)) { 2884 if ((ND = Result.getAcceptableDecl(ND))) { 2885 Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass); 2886 Visited.add(ND); 2887 } 2888 } 2889 } 2890 } 2891 2892 // Traverse using directives for qualified name lookup. 2893 if (QualifiedNameLookup) { 2894 ShadowContextRAII Shadow(Visited); 2895 DeclContext::udir_iterator I, E; 2896 for (llvm::tie(I, E) = Ctx->getUsingDirectives(); I != E; ++I) { 2897 LookupVisibleDecls((*I)->getNominatedNamespace(), Result, 2898 QualifiedNameLookup, InBaseClass, Consumer, Visited); 2899 } 2900 } 2901 2902 // Traverse the contexts of inherited C++ classes. 2903 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) { 2904 if (!Record->hasDefinition()) 2905 return; 2906 2907 for (CXXRecordDecl::base_class_iterator B = Record->bases_begin(), 2908 BEnd = Record->bases_end(); 2909 B != BEnd; ++B) { 2910 QualType BaseType = B->getType(); 2911 2912 // Don't look into dependent bases, because name lookup can't look 2913 // there anyway. 2914 if (BaseType->isDependentType()) 2915 continue; 2916 2917 const RecordType *Record = BaseType->getAs<RecordType>(); 2918 if (!Record) 2919 continue; 2920 2921 // FIXME: It would be nice to be able to determine whether referencing 2922 // a particular member would be ambiguous. For example, given 2923 // 2924 // struct A { int member; }; 2925 // struct B { int member; }; 2926 // struct C : A, B { }; 2927 // 2928 // void f(C *c) { c->### } 2929 // 2930 // accessing 'member' would result in an ambiguity. However, we 2931 // could be smart enough to qualify the member with the base 2932 // class, e.g., 2933 // 2934 // c->B::member 2935 // 2936 // or 2937 // 2938 // c->A::member 2939 2940 // Find results in this base class (and its bases). 2941 ShadowContextRAII Shadow(Visited); 2942 LookupVisibleDecls(Record->getDecl(), Result, QualifiedNameLookup, 2943 true, Consumer, Visited); 2944 } 2945 } 2946 2947 // Traverse the contexts of Objective-C classes. 2948 if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>(Ctx)) { 2949 // Traverse categories. 2950 for (ObjCCategoryDecl *Category = IFace->getCategoryList(); 2951 Category; Category = Category->getNextClassCategory()) { 2952 ShadowContextRAII Shadow(Visited); 2953 LookupVisibleDecls(Category, Result, QualifiedNameLookup, false, 2954 Consumer, Visited); 2955 } 2956 2957 // Traverse protocols. 2958 for (ObjCInterfaceDecl::all_protocol_iterator 2959 I = IFace->all_referenced_protocol_begin(), 2960 E = IFace->all_referenced_protocol_end(); I != E; ++I) { 2961 ShadowContextRAII Shadow(Visited); 2962 LookupVisibleDecls(*I, Result, QualifiedNameLookup, false, Consumer, 2963 Visited); 2964 } 2965 2966 // Traverse the superclass. 2967 if (IFace->getSuperClass()) { 2968 ShadowContextRAII Shadow(Visited); 2969 LookupVisibleDecls(IFace->getSuperClass(), Result, QualifiedNameLookup, 2970 true, Consumer, Visited); 2971 } 2972 2973 // If there is an implementation, traverse it. We do this to find 2974 // synthesized ivars. 2975 if (IFace->getImplementation()) { 2976 ShadowContextRAII Shadow(Visited); 2977 LookupVisibleDecls(IFace->getImplementation(), Result, 2978 QualifiedNameLookup, InBaseClass, Consumer, Visited); 2979 } 2980 } else if (ObjCProtocolDecl *Protocol = dyn_cast<ObjCProtocolDecl>(Ctx)) { 2981 for (ObjCProtocolDecl::protocol_iterator I = Protocol->protocol_begin(), 2982 E = Protocol->protocol_end(); I != E; ++I) { 2983 ShadowContextRAII Shadow(Visited); 2984 LookupVisibleDecls(*I, Result, QualifiedNameLookup, false, Consumer, 2985 Visited); 2986 } 2987 } else if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(Ctx)) { 2988 for (ObjCCategoryDecl::protocol_iterator I = Category->protocol_begin(), 2989 E = Category->protocol_end(); I != E; ++I) { 2990 ShadowContextRAII Shadow(Visited); 2991 LookupVisibleDecls(*I, Result, QualifiedNameLookup, false, Consumer, 2992 Visited); 2993 } 2994 2995 // If there is an implementation, traverse it. 2996 if (Category->getImplementation()) { 2997 ShadowContextRAII Shadow(Visited); 2998 LookupVisibleDecls(Category->getImplementation(), Result, 2999 QualifiedNameLookup, true, Consumer, Visited); 3000 } 3001 } 3002 } 3003 3004 static void LookupVisibleDecls(Scope *S, LookupResult &Result, 3005 UnqualUsingDirectiveSet &UDirs, 3006 VisibleDeclConsumer &Consumer, 3007 VisibleDeclsRecord &Visited) { 3008 if (!S) 3009 return; 3010 3011 if (!S->getEntity() || 3012 (!S->getParent() && 3013 !Visited.alreadyVisitedContext((DeclContext *)S->getEntity())) || 3014 ((DeclContext *)S->getEntity())->isFunctionOrMethod()) { 3015 // Walk through the declarations in this Scope. 3016 for (Scope::decl_iterator D = S->decl_begin(), DEnd = S->decl_end(); 3017 D != DEnd; ++D) { 3018 if (NamedDecl *ND = dyn_cast<NamedDecl>(*D)) 3019 if ((ND = Result.getAcceptableDecl(ND))) { 3020 Consumer.FoundDecl(ND, Visited.checkHidden(ND), 0, false); 3021 Visited.add(ND); 3022 } 3023 } 3024 } 3025 3026 // FIXME: C++ [temp.local]p8 3027 DeclContext *Entity = 0; 3028 if (S->getEntity()) { 3029 // Look into this scope's declaration context, along with any of its 3030 // parent lookup contexts (e.g., enclosing classes), up to the point 3031 // where we hit the context stored in the next outer scope. 3032 Entity = (DeclContext *)S->getEntity(); 3033 DeclContext *OuterCtx = findOuterContext(S).first; // FIXME 3034 3035 for (DeclContext *Ctx = Entity; Ctx && !Ctx->Equals(OuterCtx); 3036 Ctx = Ctx->getLookupParent()) { 3037 if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) { 3038 if (Method->isInstanceMethod()) { 3039 // For instance methods, look for ivars in the method's interface. 3040 LookupResult IvarResult(Result.getSema(), Result.getLookupName(), 3041 Result.getNameLoc(), Sema::LookupMemberName); 3042 if (ObjCInterfaceDecl *IFace = Method->getClassInterface()) { 3043 LookupVisibleDecls(IFace, IvarResult, /*QualifiedNameLookup=*/false, 3044 /*InBaseClass=*/false, Consumer, Visited); 3045 } 3046 } 3047 3048 // We've already performed all of the name lookup that we need 3049 // to for Objective-C methods; the next context will be the 3050 // outer scope. 3051 break; 3052 } 3053 3054 if (Ctx->isFunctionOrMethod()) 3055 continue; 3056 3057 LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/false, 3058 /*InBaseClass=*/false, Consumer, Visited); 3059 } 3060 } else if (!S->getParent()) { 3061 // Look into the translation unit scope. We walk through the translation 3062 // unit's declaration context, because the Scope itself won't have all of 3063 // the declarations if we loaded a precompiled header. 3064 // FIXME: We would like the translation unit's Scope object to point to the 3065 // translation unit, so we don't need this special "if" branch. However, 3066 // doing so would force the normal C++ name-lookup code to look into the 3067 // translation unit decl when the IdentifierInfo chains would suffice. 3068 // Once we fix that problem (which is part of a more general "don't look 3069 // in DeclContexts unless we have to" optimization), we can eliminate this. 3070 Entity = Result.getSema().Context.getTranslationUnitDecl(); 3071 LookupVisibleDecls(Entity, Result, /*QualifiedNameLookup=*/false, 3072 /*InBaseClass=*/false, Consumer, Visited); 3073 } 3074 3075 if (Entity) { 3076 // Lookup visible declarations in any namespaces found by using 3077 // directives. 3078 UnqualUsingDirectiveSet::const_iterator UI, UEnd; 3079 llvm::tie(UI, UEnd) = UDirs.getNamespacesFor(Entity); 3080 for (; UI != UEnd; ++UI) 3081 LookupVisibleDecls(const_cast<DeclContext *>(UI->getNominatedNamespace()), 3082 Result, /*QualifiedNameLookup=*/false, 3083 /*InBaseClass=*/false, Consumer, Visited); 3084 } 3085 3086 // Lookup names in the parent scope. 3087 ShadowContextRAII Shadow(Visited); 3088 LookupVisibleDecls(S->getParent(), Result, UDirs, Consumer, Visited); 3089 } 3090 3091 void Sema::LookupVisibleDecls(Scope *S, LookupNameKind Kind, 3092 VisibleDeclConsumer &Consumer, 3093 bool IncludeGlobalScope) { 3094 // Determine the set of using directives available during 3095 // unqualified name lookup. 3096 Scope *Initial = S; 3097 UnqualUsingDirectiveSet UDirs; 3098 if (getLangOpts().CPlusPlus) { 3099 // Find the first namespace or translation-unit scope. 3100 while (S && !isNamespaceOrTranslationUnitScope(S)) 3101 S = S->getParent(); 3102 3103 UDirs.visitScopeChain(Initial, S); 3104 } 3105 UDirs.done(); 3106 3107 // Look for visible declarations. 3108 LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind); 3109 VisibleDeclsRecord Visited; 3110 if (!IncludeGlobalScope) 3111 Visited.visitedContext(Context.getTranslationUnitDecl()); 3112 ShadowContextRAII Shadow(Visited); 3113 ::LookupVisibleDecls(Initial, Result, UDirs, Consumer, Visited); 3114 } 3115 3116 void Sema::LookupVisibleDecls(DeclContext *Ctx, LookupNameKind Kind, 3117 VisibleDeclConsumer &Consumer, 3118 bool IncludeGlobalScope) { 3119 LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind); 3120 VisibleDeclsRecord Visited; 3121 if (!IncludeGlobalScope) 3122 Visited.visitedContext(Context.getTranslationUnitDecl()); 3123 ShadowContextRAII Shadow(Visited); 3124 ::LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/true, 3125 /*InBaseClass=*/false, Consumer, Visited); 3126 } 3127 3128 /// LookupOrCreateLabel - Do a name lookup of a label with the specified name. 3129 /// If GnuLabelLoc is a valid source location, then this is a definition 3130 /// of an __label__ label name, otherwise it is a normal label definition 3131 /// or use. 3132 LabelDecl *Sema::LookupOrCreateLabel(IdentifierInfo *II, SourceLocation Loc, 3133 SourceLocation GnuLabelLoc) { 3134 // Do a lookup to see if we have a label with this name already. 3135 NamedDecl *Res = 0; 3136 3137 if (GnuLabelLoc.isValid()) { 3138 // Local label definitions always shadow existing labels. 3139 Res = LabelDecl::Create(Context, CurContext, Loc, II, GnuLabelLoc); 3140 Scope *S = CurScope; 3141 PushOnScopeChains(Res, S, true); 3142 return cast<LabelDecl>(Res); 3143 } 3144 3145 // Not a GNU local label. 3146 Res = LookupSingleName(CurScope, II, Loc, LookupLabel, NotForRedeclaration); 3147 // If we found a label, check to see if it is in the same context as us. 3148 // When in a Block, we don't want to reuse a label in an enclosing function. 3149 if (Res && Res->getDeclContext() != CurContext) 3150 Res = 0; 3151 if (Res == 0) { 3152 // If not forward referenced or defined already, create the backing decl. 3153 Res = LabelDecl::Create(Context, CurContext, Loc, II); 3154 Scope *S = CurScope->getFnParent(); 3155 assert(S && "Not in a function?"); 3156 PushOnScopeChains(Res, S, true); 3157 } 3158 return cast<LabelDecl>(Res); 3159 } 3160 3161 //===----------------------------------------------------------------------===// 3162 // Typo correction 3163 //===----------------------------------------------------------------------===// 3164 3165 namespace { 3166 3167 typedef llvm::StringMap<TypoCorrection, llvm::BumpPtrAllocator> TypoResultsMap; 3168 typedef std::map<unsigned, TypoResultsMap> TypoEditDistanceMap; 3169 3170 static const unsigned MaxTypoDistanceResultSets = 5; 3171 3172 class TypoCorrectionConsumer : public VisibleDeclConsumer { 3173 /// \brief The name written that is a typo in the source. 3174 StringRef Typo; 3175 3176 /// \brief The results found that have the smallest edit distance 3177 /// found (so far) with the typo name. 3178 /// 3179 /// The pointer value being set to the current DeclContext indicates 3180 /// whether there is a keyword with this name. 3181 TypoEditDistanceMap BestResults; 3182 3183 Sema &SemaRef; 3184 3185 public: 3186 explicit TypoCorrectionConsumer(Sema &SemaRef, IdentifierInfo *Typo) 3187 : Typo(Typo->getName()), 3188 SemaRef(SemaRef) { } 3189 3190 virtual void FoundDecl(NamedDecl *ND, NamedDecl *Hiding, DeclContext *Ctx, 3191 bool InBaseClass); 3192 void FoundName(StringRef Name); 3193 void addKeywordResult(StringRef Keyword); 3194 void addName(StringRef Name, NamedDecl *ND, unsigned Distance, 3195 NestedNameSpecifier *NNS=NULL, bool isKeyword=false); 3196 void addCorrection(TypoCorrection Correction); 3197 3198 typedef TypoResultsMap::iterator result_iterator; 3199 typedef TypoEditDistanceMap::iterator distance_iterator; 3200 distance_iterator begin() { return BestResults.begin(); } 3201 distance_iterator end() { return BestResults.end(); } 3202 void erase(distance_iterator I) { BestResults.erase(I); } 3203 unsigned size() const { return BestResults.size(); } 3204 bool empty() const { return BestResults.empty(); } 3205 3206 TypoCorrection &operator[](StringRef Name) { 3207 return BestResults.begin()->second[Name]; 3208 } 3209 3210 unsigned getBestEditDistance(bool Normalized) { 3211 if (BestResults.empty()) 3212 return (std::numeric_limits<unsigned>::max)(); 3213 3214 unsigned BestED = BestResults.begin()->first; 3215 return Normalized ? TypoCorrection::NormalizeEditDistance(BestED) : BestED; 3216 } 3217 }; 3218 3219 } 3220 3221 void TypoCorrectionConsumer::FoundDecl(NamedDecl *ND, NamedDecl *Hiding, 3222 DeclContext *Ctx, bool InBaseClass) { 3223 // Don't consider hidden names for typo correction. 3224 if (Hiding) 3225 return; 3226 3227 // Only consider entities with identifiers for names, ignoring 3228 // special names (constructors, overloaded operators, selectors, 3229 // etc.). 3230 IdentifierInfo *Name = ND->getIdentifier(); 3231 if (!Name) 3232 return; 3233 3234 FoundName(Name->getName()); 3235 } 3236 3237 void TypoCorrectionConsumer::FoundName(StringRef Name) { 3238 // Use a simple length-based heuristic to determine the minimum possible 3239 // edit distance. If the minimum isn't good enough, bail out early. 3240 unsigned MinED = abs((int)Name.size() - (int)Typo.size()); 3241 if (MinED && Typo.size() / MinED < 3) 3242 return; 3243 3244 // Compute an upper bound on the allowable edit distance, so that the 3245 // edit-distance algorithm can short-circuit. 3246 unsigned UpperBound = (Typo.size() + 2) / 3; 3247 3248 // Compute the edit distance between the typo and the name of this 3249 // entity, and add the identifier to the list of results. 3250 addName(Name, NULL, Typo.edit_distance(Name, true, UpperBound)); 3251 } 3252 3253 void TypoCorrectionConsumer::addKeywordResult(StringRef Keyword) { 3254 // Compute the edit distance between the typo and this keyword, 3255 // and add the keyword to the list of results. 3256 addName(Keyword, NULL, Typo.edit_distance(Keyword), NULL, true); 3257 } 3258 3259 void TypoCorrectionConsumer::addName(StringRef Name, 3260 NamedDecl *ND, 3261 unsigned Distance, 3262 NestedNameSpecifier *NNS, 3263 bool isKeyword) { 3264 TypoCorrection TC(&SemaRef.Context.Idents.get(Name), ND, NNS, Distance); 3265 if (isKeyword) TC.makeKeyword(); 3266 addCorrection(TC); 3267 } 3268 3269 void TypoCorrectionConsumer::addCorrection(TypoCorrection Correction) { 3270 StringRef Name = Correction.getCorrectionAsIdentifierInfo()->getName(); 3271 TypoResultsMap &Map = BestResults[Correction.getEditDistance(false)]; 3272 3273 TypoCorrection &CurrentCorrection = Map[Name]; 3274 if (!CurrentCorrection || 3275 // FIXME: The following should be rolled up into an operator< on 3276 // TypoCorrection with a more principled definition. 3277 CurrentCorrection.isKeyword() < Correction.isKeyword() || 3278 Correction.getAsString(SemaRef.getLangOpts()) < 3279 CurrentCorrection.getAsString(SemaRef.getLangOpts())) 3280 CurrentCorrection = Correction; 3281 3282 while (BestResults.size() > MaxTypoDistanceResultSets) 3283 erase(llvm::prior(BestResults.end())); 3284 } 3285 3286 // Fill the supplied vector with the IdentifierInfo pointers for each piece of 3287 // the given NestedNameSpecifier (i.e. given a NestedNameSpecifier "foo::bar::", 3288 // fill the vector with the IdentifierInfo pointers for "foo" and "bar"). 3289 static void getNestedNameSpecifierIdentifiers( 3290 NestedNameSpecifier *NNS, 3291 SmallVectorImpl<const IdentifierInfo*> &Identifiers) { 3292 if (NestedNameSpecifier *Prefix = NNS->getPrefix()) 3293 getNestedNameSpecifierIdentifiers(Prefix, Identifiers); 3294 else 3295 Identifiers.clear(); 3296 3297 const IdentifierInfo *II = NULL; 3298 3299 switch (NNS->getKind()) { 3300 case NestedNameSpecifier::Identifier: 3301 II = NNS->getAsIdentifier(); 3302 break; 3303 3304 case NestedNameSpecifier::Namespace: 3305 if (NNS->getAsNamespace()->isAnonymousNamespace()) 3306 return; 3307 II = NNS->getAsNamespace()->getIdentifier(); 3308 break; 3309 3310 case NestedNameSpecifier::NamespaceAlias: 3311 II = NNS->getAsNamespaceAlias()->getIdentifier(); 3312 break; 3313 3314 case NestedNameSpecifier::TypeSpecWithTemplate: 3315 case NestedNameSpecifier::TypeSpec: 3316 II = QualType(NNS->getAsType(), 0).getBaseTypeIdentifier(); 3317 break; 3318 3319 case NestedNameSpecifier::Global: 3320 return; 3321 } 3322 3323 if (II) 3324 Identifiers.push_back(II); 3325 } 3326 3327 namespace { 3328 3329 class SpecifierInfo { 3330 public: 3331 DeclContext* DeclCtx; 3332 NestedNameSpecifier* NameSpecifier; 3333 unsigned EditDistance; 3334 3335 SpecifierInfo(DeclContext *Ctx, NestedNameSpecifier *NNS, unsigned ED) 3336 : DeclCtx(Ctx), NameSpecifier(NNS), EditDistance(ED) {} 3337 }; 3338 3339 typedef SmallVector<DeclContext*, 4> DeclContextList; 3340 typedef SmallVector<SpecifierInfo, 16> SpecifierInfoList; 3341 3342 class NamespaceSpecifierSet { 3343 ASTContext &Context; 3344 DeclContextList CurContextChain; 3345 SmallVector<const IdentifierInfo*, 4> CurContextIdentifiers; 3346 SmallVector<const IdentifierInfo*, 4> CurNameSpecifierIdentifiers; 3347 bool isSorted; 3348 3349 SpecifierInfoList Specifiers; 3350 llvm::SmallSetVector<unsigned, 4> Distances; 3351 llvm::DenseMap<unsigned, SpecifierInfoList> DistanceMap; 3352 3353 /// \brief Helper for building the list of DeclContexts between the current 3354 /// context and the top of the translation unit 3355 static DeclContextList BuildContextChain(DeclContext *Start); 3356 3357 void SortNamespaces(); 3358 3359 public: 3360 NamespaceSpecifierSet(ASTContext &Context, DeclContext *CurContext, 3361 CXXScopeSpec *CurScopeSpec) 3362 : Context(Context), CurContextChain(BuildContextChain(CurContext)), 3363 isSorted(true) { 3364 if (CurScopeSpec && CurScopeSpec->getScopeRep()) 3365 getNestedNameSpecifierIdentifiers(CurScopeSpec->getScopeRep(), 3366 CurNameSpecifierIdentifiers); 3367 // Build the list of identifiers that would be used for an absolute 3368 // (from the global context) NestedNameSpecifier refering to the current 3369 // context. 3370 for (DeclContextList::reverse_iterator C = CurContextChain.rbegin(), 3371 CEnd = CurContextChain.rend(); 3372 C != CEnd; ++C) { 3373 if (NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(*C)) 3374 CurContextIdentifiers.push_back(ND->getIdentifier()); 3375 } 3376 } 3377 3378 /// \brief Add the namespace to the set, computing the corresponding 3379 /// NestedNameSpecifier and its distance in the process. 3380 void AddNamespace(NamespaceDecl *ND); 3381 3382 typedef SpecifierInfoList::iterator iterator; 3383 iterator begin() { 3384 if (!isSorted) SortNamespaces(); 3385 return Specifiers.begin(); 3386 } 3387 iterator end() { return Specifiers.end(); } 3388 }; 3389 3390 } 3391 3392 DeclContextList NamespaceSpecifierSet::BuildContextChain(DeclContext *Start) { 3393 assert(Start && "Bulding a context chain from a null context"); 3394 DeclContextList Chain; 3395 for (DeclContext *DC = Start->getPrimaryContext(); DC != NULL; 3396 DC = DC->getLookupParent()) { 3397 NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(DC); 3398 if (!DC->isInlineNamespace() && !DC->isTransparentContext() && 3399 !(ND && ND->isAnonymousNamespace())) 3400 Chain.push_back(DC->getPrimaryContext()); 3401 } 3402 return Chain; 3403 } 3404 3405 void NamespaceSpecifierSet::SortNamespaces() { 3406 SmallVector<unsigned, 4> sortedDistances; 3407 sortedDistances.append(Distances.begin(), Distances.end()); 3408 3409 if (sortedDistances.size() > 1) 3410 std::sort(sortedDistances.begin(), sortedDistances.end()); 3411 3412 Specifiers.clear(); 3413 for (SmallVector<unsigned, 4>::iterator DI = sortedDistances.begin(), 3414 DIEnd = sortedDistances.end(); 3415 DI != DIEnd; ++DI) { 3416 SpecifierInfoList &SpecList = DistanceMap[*DI]; 3417 Specifiers.append(SpecList.begin(), SpecList.end()); 3418 } 3419 3420 isSorted = true; 3421 } 3422 3423 void NamespaceSpecifierSet::AddNamespace(NamespaceDecl *ND) { 3424 DeclContext *Ctx = cast<DeclContext>(ND); 3425 NestedNameSpecifier *NNS = NULL; 3426 unsigned NumSpecifiers = 0; 3427 DeclContextList NamespaceDeclChain(BuildContextChain(Ctx)); 3428 DeclContextList FullNamespaceDeclChain(NamespaceDeclChain); 3429 3430 // Eliminate common elements from the two DeclContext chains. 3431 for (DeclContextList::reverse_iterator C = CurContextChain.rbegin(), 3432 CEnd = CurContextChain.rend(); 3433 C != CEnd && !NamespaceDeclChain.empty() && 3434 NamespaceDeclChain.back() == *C; ++C) { 3435 NamespaceDeclChain.pop_back(); 3436 } 3437 3438 // Add an explicit leading '::' specifier if needed. 3439 if (NamespaceDecl *ND = 3440 NamespaceDeclChain.empty() ? NULL : 3441 dyn_cast_or_null<NamespaceDecl>(NamespaceDeclChain.back())) { 3442 IdentifierInfo *Name = ND->getIdentifier(); 3443 if (std::find(CurContextIdentifiers.begin(), CurContextIdentifiers.end(), 3444 Name) != CurContextIdentifiers.end() || 3445 std::find(CurNameSpecifierIdentifiers.begin(), 3446 CurNameSpecifierIdentifiers.end(), 3447 Name) != CurNameSpecifierIdentifiers.end()) { 3448 NamespaceDeclChain = FullNamespaceDeclChain; 3449 NNS = NestedNameSpecifier::GlobalSpecifier(Context); 3450 } 3451 } 3452 3453 // Build the NestedNameSpecifier from what is left of the NamespaceDeclChain 3454 for (DeclContextList::reverse_iterator C = NamespaceDeclChain.rbegin(), 3455 CEnd = NamespaceDeclChain.rend(); 3456 C != CEnd; ++C) { 3457 NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(*C); 3458 if (ND) { 3459 NNS = NestedNameSpecifier::Create(Context, NNS, ND); 3460 ++NumSpecifiers; 3461 } 3462 } 3463 3464 // If the built NestedNameSpecifier would be replacing an existing 3465 // NestedNameSpecifier, use the number of component identifiers that 3466 // would need to be changed as the edit distance instead of the number 3467 // of components in the built NestedNameSpecifier. 3468 if (NNS && !CurNameSpecifierIdentifiers.empty()) { 3469 SmallVector<const IdentifierInfo*, 4> NewNameSpecifierIdentifiers; 3470 getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers); 3471 NumSpecifiers = llvm::ComputeEditDistance( 3472 llvm::ArrayRef<const IdentifierInfo*>(CurNameSpecifierIdentifiers), 3473 llvm::ArrayRef<const IdentifierInfo*>(NewNameSpecifierIdentifiers)); 3474 } 3475 3476 isSorted = false; 3477 Distances.insert(NumSpecifiers); 3478 DistanceMap[NumSpecifiers].push_back(SpecifierInfo(Ctx, NNS, NumSpecifiers)); 3479 } 3480 3481 /// \brief Perform name lookup for a possible result for typo correction. 3482 static void LookupPotentialTypoResult(Sema &SemaRef, 3483 LookupResult &Res, 3484 IdentifierInfo *Name, 3485 Scope *S, CXXScopeSpec *SS, 3486 DeclContext *MemberContext, 3487 bool EnteringContext, 3488 bool isObjCIvarLookup) { 3489 Res.suppressDiagnostics(); 3490 Res.clear(); 3491 Res.setLookupName(Name); 3492 if (MemberContext) { 3493 if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(MemberContext)) { 3494 if (isObjCIvarLookup) { 3495 if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(Name)) { 3496 Res.addDecl(Ivar); 3497 Res.resolveKind(); 3498 return; 3499 } 3500 } 3501 3502 if (ObjCPropertyDecl *Prop = Class->FindPropertyDeclaration(Name)) { 3503 Res.addDecl(Prop); 3504 Res.resolveKind(); 3505 return; 3506 } 3507 } 3508 3509 SemaRef.LookupQualifiedName(Res, MemberContext); 3510 return; 3511 } 3512 3513 SemaRef.LookupParsedName(Res, S, SS, /*AllowBuiltinCreation=*/false, 3514 EnteringContext); 3515 3516 // Fake ivar lookup; this should really be part of 3517 // LookupParsedName. 3518 if (ObjCMethodDecl *Method = SemaRef.getCurMethodDecl()) { 3519 if (Method->isInstanceMethod() && Method->getClassInterface() && 3520 (Res.empty() || 3521 (Res.isSingleResult() && 3522 Res.getFoundDecl()->isDefinedOutsideFunctionOrMethod()))) { 3523 if (ObjCIvarDecl *IV 3524 = Method->getClassInterface()->lookupInstanceVariable(Name)) { 3525 Res.addDecl(IV); 3526 Res.resolveKind(); 3527 } 3528 } 3529 } 3530 } 3531 3532 /// \brief Add keywords to the consumer as possible typo corrections. 3533 static void AddKeywordsToConsumer(Sema &SemaRef, 3534 TypoCorrectionConsumer &Consumer, 3535 Scope *S, CorrectionCandidateCallback &CCC) { 3536 if (CCC.WantObjCSuper) 3537 Consumer.addKeywordResult("super"); 3538 3539 if (CCC.WantTypeSpecifiers) { 3540 // Add type-specifier keywords to the set of results. 3541 const char *CTypeSpecs[] = { 3542 "char", "const", "double", "enum", "float", "int", "long", "short", 3543 "signed", "struct", "union", "unsigned", "void", "volatile", 3544 "_Complex", "_Imaginary", 3545 // storage-specifiers as well 3546 "extern", "inline", "static", "typedef" 3547 }; 3548 3549 const unsigned NumCTypeSpecs = sizeof(CTypeSpecs) / sizeof(CTypeSpecs[0]); 3550 for (unsigned I = 0; I != NumCTypeSpecs; ++I) 3551 Consumer.addKeywordResult(CTypeSpecs[I]); 3552 3553 if (SemaRef.getLangOpts().C99) 3554 Consumer.addKeywordResult("restrict"); 3555 if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus) 3556 Consumer.addKeywordResult("bool"); 3557 else if (SemaRef.getLangOpts().C99) 3558 Consumer.addKeywordResult("_Bool"); 3559 3560 if (SemaRef.getLangOpts().CPlusPlus) { 3561 Consumer.addKeywordResult("class"); 3562 Consumer.addKeywordResult("typename"); 3563 Consumer.addKeywordResult("wchar_t"); 3564 3565 if (SemaRef.getLangOpts().CPlusPlus0x) { 3566 Consumer.addKeywordResult("char16_t"); 3567 Consumer.addKeywordResult("char32_t"); 3568 Consumer.addKeywordResult("constexpr"); 3569 Consumer.addKeywordResult("decltype"); 3570 Consumer.addKeywordResult("thread_local"); 3571 } 3572 } 3573 3574 if (SemaRef.getLangOpts().GNUMode) 3575 Consumer.addKeywordResult("typeof"); 3576 } 3577 3578 if (CCC.WantCXXNamedCasts && SemaRef.getLangOpts().CPlusPlus) { 3579 Consumer.addKeywordResult("const_cast"); 3580 Consumer.addKeywordResult("dynamic_cast"); 3581 Consumer.addKeywordResult("reinterpret_cast"); 3582 Consumer.addKeywordResult("static_cast"); 3583 } 3584 3585 if (CCC.WantExpressionKeywords) { 3586 Consumer.addKeywordResult("sizeof"); 3587 if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus) { 3588 Consumer.addKeywordResult("false"); 3589 Consumer.addKeywordResult("true"); 3590 } 3591 3592 if (SemaRef.getLangOpts().CPlusPlus) { 3593 const char *CXXExprs[] = { 3594 "delete", "new", "operator", "throw", "typeid" 3595 }; 3596 const unsigned NumCXXExprs = sizeof(CXXExprs) / sizeof(CXXExprs[0]); 3597 for (unsigned I = 0; I != NumCXXExprs; ++I) 3598 Consumer.addKeywordResult(CXXExprs[I]); 3599 3600 if (isa<CXXMethodDecl>(SemaRef.CurContext) && 3601 cast<CXXMethodDecl>(SemaRef.CurContext)->isInstance()) 3602 Consumer.addKeywordResult("this"); 3603 3604 if (SemaRef.getLangOpts().CPlusPlus0x) { 3605 Consumer.addKeywordResult("alignof"); 3606 Consumer.addKeywordResult("nullptr"); 3607 } 3608 } 3609 } 3610 3611 if (CCC.WantRemainingKeywords) { 3612 if (SemaRef.getCurFunctionOrMethodDecl() || SemaRef.getCurBlock()) { 3613 // Statements. 3614 const char *CStmts[] = { 3615 "do", "else", "for", "goto", "if", "return", "switch", "while" }; 3616 const unsigned NumCStmts = sizeof(CStmts) / sizeof(CStmts[0]); 3617 for (unsigned I = 0; I != NumCStmts; ++I) 3618 Consumer.addKeywordResult(CStmts[I]); 3619 3620 if (SemaRef.getLangOpts().CPlusPlus) { 3621 Consumer.addKeywordResult("catch"); 3622 Consumer.addKeywordResult("try"); 3623 } 3624 3625 if (S && S->getBreakParent()) 3626 Consumer.addKeywordResult("break"); 3627 3628 if (S && S->getContinueParent()) 3629 Consumer.addKeywordResult("continue"); 3630 3631 if (!SemaRef.getCurFunction()->SwitchStack.empty()) { 3632 Consumer.addKeywordResult("case"); 3633 Consumer.addKeywordResult("default"); 3634 } 3635 } else { 3636 if (SemaRef.getLangOpts().CPlusPlus) { 3637 Consumer.addKeywordResult("namespace"); 3638 Consumer.addKeywordResult("template"); 3639 } 3640 3641 if (S && S->isClassScope()) { 3642 Consumer.addKeywordResult("explicit"); 3643 Consumer.addKeywordResult("friend"); 3644 Consumer.addKeywordResult("mutable"); 3645 Consumer.addKeywordResult("private"); 3646 Consumer.addKeywordResult("protected"); 3647 Consumer.addKeywordResult("public"); 3648 Consumer.addKeywordResult("virtual"); 3649 } 3650 } 3651 3652 if (SemaRef.getLangOpts().CPlusPlus) { 3653 Consumer.addKeywordResult("using"); 3654 3655 if (SemaRef.getLangOpts().CPlusPlus0x) 3656 Consumer.addKeywordResult("static_assert"); 3657 } 3658 } 3659 } 3660 3661 static bool isCandidateViable(CorrectionCandidateCallback &CCC, 3662 TypoCorrection &Candidate) { 3663 Candidate.setCallbackDistance(CCC.RankCandidate(Candidate)); 3664 return Candidate.getEditDistance(false) != TypoCorrection::InvalidDistance; 3665 } 3666 3667 /// \brief Try to "correct" a typo in the source code by finding 3668 /// visible declarations whose names are similar to the name that was 3669 /// present in the source code. 3670 /// 3671 /// \param TypoName the \c DeclarationNameInfo structure that contains 3672 /// the name that was present in the source code along with its location. 3673 /// 3674 /// \param LookupKind the name-lookup criteria used to search for the name. 3675 /// 3676 /// \param S the scope in which name lookup occurs. 3677 /// 3678 /// \param SS the nested-name-specifier that precedes the name we're 3679 /// looking for, if present. 3680 /// 3681 /// \param CCC A CorrectionCandidateCallback object that provides further 3682 /// validation of typo correction candidates. It also provides flags for 3683 /// determining the set of keywords permitted. 3684 /// 3685 /// \param MemberContext if non-NULL, the context in which to look for 3686 /// a member access expression. 3687 /// 3688 /// \param EnteringContext whether we're entering the context described by 3689 /// the nested-name-specifier SS. 3690 /// 3691 /// \param OPT when non-NULL, the search for visible declarations will 3692 /// also walk the protocols in the qualified interfaces of \p OPT. 3693 /// 3694 /// \returns a \c TypoCorrection containing the corrected name if the typo 3695 /// along with information such as the \c NamedDecl where the corrected name 3696 /// was declared, and any additional \c NestedNameSpecifier needed to access 3697 /// it (C++ only). The \c TypoCorrection is empty if there is no correction. 3698 TypoCorrection Sema::CorrectTypo(const DeclarationNameInfo &TypoName, 3699 Sema::LookupNameKind LookupKind, 3700 Scope *S, CXXScopeSpec *SS, 3701 CorrectionCandidateCallback &CCC, 3702 DeclContext *MemberContext, 3703 bool EnteringContext, 3704 const ObjCObjectPointerType *OPT) { 3705 if (Diags.hasFatalErrorOccurred() || !getLangOpts().SpellChecking) 3706 return TypoCorrection(); 3707 3708 // In Microsoft mode, don't perform typo correction in a template member 3709 // function dependent context because it interferes with the "lookup into 3710 // dependent bases of class templates" feature. 3711 if (getLangOpts().MicrosoftMode && CurContext->isDependentContext() && 3712 isa<CXXMethodDecl>(CurContext)) 3713 return TypoCorrection(); 3714 3715 // We only attempt to correct typos for identifiers. 3716 IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo(); 3717 if (!Typo) 3718 return TypoCorrection(); 3719 3720 // If the scope specifier itself was invalid, don't try to correct 3721 // typos. 3722 if (SS && SS->isInvalid()) 3723 return TypoCorrection(); 3724 3725 // Never try to correct typos during template deduction or 3726 // instantiation. 3727 if (!ActiveTemplateInstantiations.empty()) 3728 return TypoCorrection(); 3729 3730 NamespaceSpecifierSet Namespaces(Context, CurContext, SS); 3731 3732 TypoCorrectionConsumer Consumer(*this, Typo); 3733 3734 // If a callback object considers an empty typo correction candidate to be 3735 // viable, assume it does not do any actual validation of the candidates. 3736 TypoCorrection EmptyCorrection; 3737 bool ValidatingCallback = !isCandidateViable(CCC, EmptyCorrection); 3738 3739 // Perform name lookup to find visible, similarly-named entities. 3740 bool IsUnqualifiedLookup = false; 3741 DeclContext *QualifiedDC = MemberContext; 3742 if (MemberContext) { 3743 LookupVisibleDecls(MemberContext, LookupKind, Consumer); 3744 3745 // Look in qualified interfaces. 3746 if (OPT) { 3747 for (ObjCObjectPointerType::qual_iterator 3748 I = OPT->qual_begin(), E = OPT->qual_end(); 3749 I != E; ++I) 3750 LookupVisibleDecls(*I, LookupKind, Consumer); 3751 } 3752 } else if (SS && SS->isSet()) { 3753 QualifiedDC = computeDeclContext(*SS, EnteringContext); 3754 if (!QualifiedDC) 3755 return TypoCorrection(); 3756 3757 // Provide a stop gap for files that are just seriously broken. Trying 3758 // to correct all typos can turn into a HUGE performance penalty, causing 3759 // some files to take minutes to get rejected by the parser. 3760 if (TyposCorrected + UnqualifiedTyposCorrected.size() >= 20) 3761 return TypoCorrection(); 3762 ++TyposCorrected; 3763 3764 LookupVisibleDecls(QualifiedDC, LookupKind, Consumer); 3765 } else { 3766 IsUnqualifiedLookup = true; 3767 UnqualifiedTyposCorrectedMap::iterator Cached 3768 = UnqualifiedTyposCorrected.find(Typo); 3769 if (Cached != UnqualifiedTyposCorrected.end()) { 3770 // Add the cached value, unless it's a keyword or fails validation. In the 3771 // keyword case, we'll end up adding the keyword below. 3772 if (Cached->second) { 3773 if (!Cached->second.isKeyword() && 3774 isCandidateViable(CCC, Cached->second)) 3775 Consumer.addCorrection(Cached->second); 3776 } else { 3777 // Only honor no-correction cache hits when a callback that will validate 3778 // correction candidates is not being used. 3779 if (!ValidatingCallback) 3780 return TypoCorrection(); 3781 } 3782 } 3783 if (Cached == UnqualifiedTyposCorrected.end()) { 3784 // Provide a stop gap for files that are just seriously broken. Trying 3785 // to correct all typos can turn into a HUGE performance penalty, causing 3786 // some files to take minutes to get rejected by the parser. 3787 if (TyposCorrected + UnqualifiedTyposCorrected.size() >= 20) 3788 return TypoCorrection(); 3789 } 3790 } 3791 3792 // Determine whether we are going to search in the various namespaces for 3793 // corrections. 3794 bool SearchNamespaces 3795 = getLangOpts().CPlusPlus && 3796 (IsUnqualifiedLookup || (QualifiedDC && QualifiedDC->isNamespace())); 3797 3798 if (IsUnqualifiedLookup || SearchNamespaces) { 3799 // For unqualified lookup, look through all of the names that we have 3800 // seen in this translation unit. 3801 // FIXME: Re-add the ability to skip very unlikely potential corrections. 3802 for (IdentifierTable::iterator I = Context.Idents.begin(), 3803 IEnd = Context.Idents.end(); 3804 I != IEnd; ++I) 3805 Consumer.FoundName(I->getKey()); 3806 3807 // Walk through identifiers in external identifier sources. 3808 // FIXME: Re-add the ability to skip very unlikely potential corrections. 3809 if (IdentifierInfoLookup *External 3810 = Context.Idents.getExternalIdentifierLookup()) { 3811 OwningPtr<IdentifierIterator> Iter(External->getIdentifiers()); 3812 do { 3813 StringRef Name = Iter->Next(); 3814 if (Name.empty()) 3815 break; 3816 3817 Consumer.FoundName(Name); 3818 } while (true); 3819 } 3820 } 3821 3822 AddKeywordsToConsumer(*this, Consumer, S, CCC); 3823 3824 // If we haven't found anything, we're done. 3825 if (Consumer.empty()) { 3826 // If this was an unqualified lookup, note that no correction was found. 3827 if (IsUnqualifiedLookup) 3828 (void)UnqualifiedTyposCorrected[Typo]; 3829 3830 return TypoCorrection(); 3831 } 3832 3833 // Make sure that the user typed at least 3 characters for each correction 3834 // made. Otherwise, we don't even both looking at the results. 3835 unsigned ED = Consumer.getBestEditDistance(true); 3836 if (ED > 0 && Typo->getName().size() / ED < 3) { 3837 // If this was an unqualified lookup, note that no correction was found. 3838 if (IsUnqualifiedLookup) 3839 (void)UnqualifiedTyposCorrected[Typo]; 3840 3841 return TypoCorrection(); 3842 } 3843 3844 // Build the NestedNameSpecifiers for the KnownNamespaces, if we're going 3845 // to search those namespaces. 3846 if (SearchNamespaces) { 3847 // Load any externally-known namespaces. 3848 if (ExternalSource && !LoadedExternalKnownNamespaces) { 3849 SmallVector<NamespaceDecl *, 4> ExternalKnownNamespaces; 3850 LoadedExternalKnownNamespaces = true; 3851 ExternalSource->ReadKnownNamespaces(ExternalKnownNamespaces); 3852 for (unsigned I = 0, N = ExternalKnownNamespaces.size(); I != N; ++I) 3853 KnownNamespaces[ExternalKnownNamespaces[I]] = true; 3854 } 3855 3856 for (llvm::DenseMap<NamespaceDecl*, bool>::iterator 3857 KNI = KnownNamespaces.begin(), 3858 KNIEnd = KnownNamespaces.end(); 3859 KNI != KNIEnd; ++KNI) 3860 Namespaces.AddNamespace(KNI->first); 3861 } 3862 3863 // Weed out any names that could not be found by name lookup or, if a 3864 // CorrectionCandidateCallback object was provided, failed validation. 3865 llvm::SmallVector<TypoCorrection, 16> QualifiedResults; 3866 LookupResult TmpRes(*this, TypoName, LookupKind); 3867 TmpRes.suppressDiagnostics(); 3868 while (!Consumer.empty()) { 3869 TypoCorrectionConsumer::distance_iterator DI = Consumer.begin(); 3870 unsigned ED = DI->first; 3871 for (TypoCorrectionConsumer::result_iterator I = DI->second.begin(), 3872 IEnd = DI->second.end(); 3873 I != IEnd; /* Increment in loop. */) { 3874 // If the item already has been looked up or is a keyword, keep it. 3875 // If a validator callback object was given, drop the correction 3876 // unless it passes validation. 3877 if (I->second.isResolved()) { 3878 TypoCorrectionConsumer::result_iterator Prev = I; 3879 ++I; 3880 if (!isCandidateViable(CCC, Prev->second)) 3881 DI->second.erase(Prev); 3882 continue; 3883 } 3884 3885 // Perform name lookup on this name. 3886 IdentifierInfo *Name = I->second.getCorrectionAsIdentifierInfo(); 3887 LookupPotentialTypoResult(*this, TmpRes, Name, S, SS, MemberContext, 3888 EnteringContext, CCC.IsObjCIvarLookup); 3889 3890 switch (TmpRes.getResultKind()) { 3891 case LookupResult::NotFound: 3892 case LookupResult::NotFoundInCurrentInstantiation: 3893 case LookupResult::FoundUnresolvedValue: 3894 QualifiedResults.push_back(I->second); 3895 // We didn't find this name in our scope, or didn't like what we found; 3896 // ignore it. 3897 { 3898 TypoCorrectionConsumer::result_iterator Next = I; 3899 ++Next; 3900 DI->second.erase(I); 3901 I = Next; 3902 } 3903 break; 3904 3905 case LookupResult::Ambiguous: 3906 // We don't deal with ambiguities. 3907 return TypoCorrection(); 3908 3909 case LookupResult::FoundOverloaded: { 3910 TypoCorrectionConsumer::result_iterator Prev = I; 3911 // Store all of the Decls for overloaded symbols 3912 for (LookupResult::iterator TRD = TmpRes.begin(), 3913 TRDEnd = TmpRes.end(); 3914 TRD != TRDEnd; ++TRD) 3915 I->second.addCorrectionDecl(*TRD); 3916 ++I; 3917 if (!isCandidateViable(CCC, Prev->second)) 3918 DI->second.erase(Prev); 3919 break; 3920 } 3921 3922 case LookupResult::Found: { 3923 TypoCorrectionConsumer::result_iterator Prev = I; 3924 I->second.setCorrectionDecl(TmpRes.getAsSingle<NamedDecl>()); 3925 ++I; 3926 if (!isCandidateViable(CCC, Prev->second)) 3927 DI->second.erase(Prev); 3928 break; 3929 } 3930 3931 } 3932 } 3933 3934 if (DI->second.empty()) 3935 Consumer.erase(DI); 3936 else if (!getLangOpts().CPlusPlus || QualifiedResults.empty() || !ED) 3937 // If there are results in the closest possible bucket, stop 3938 break; 3939 3940 // Only perform the qualified lookups for C++ 3941 if (SearchNamespaces) { 3942 TmpRes.suppressDiagnostics(); 3943 for (llvm::SmallVector<TypoCorrection, 3944 16>::iterator QRI = QualifiedResults.begin(), 3945 QRIEnd = QualifiedResults.end(); 3946 QRI != QRIEnd; ++QRI) { 3947 for (NamespaceSpecifierSet::iterator NI = Namespaces.begin(), 3948 NIEnd = Namespaces.end(); 3949 NI != NIEnd; ++NI) { 3950 DeclContext *Ctx = NI->DeclCtx; 3951 3952 // FIXME: Stop searching once the namespaces are too far away to create 3953 // acceptable corrections for this identifier (since the namespaces 3954 // are sorted in ascending order by edit distance). 3955 3956 TmpRes.clear(); 3957 TmpRes.setLookupName(QRI->getCorrectionAsIdentifierInfo()); 3958 if (!LookupQualifiedName(TmpRes, Ctx)) continue; 3959 3960 // Any corrections added below will be validated in subsequent 3961 // iterations of the main while() loop over the Consumer's contents. 3962 switch (TmpRes.getResultKind()) { 3963 case LookupResult::Found: { 3964 TypoCorrection TC(*QRI); 3965 TC.setCorrectionDecl(TmpRes.getAsSingle<NamedDecl>()); 3966 TC.setCorrectionSpecifier(NI->NameSpecifier); 3967 TC.setQualifierDistance(NI->EditDistance); 3968 Consumer.addCorrection(TC); 3969 break; 3970 } 3971 case LookupResult::FoundOverloaded: { 3972 TypoCorrection TC(*QRI); 3973 TC.setCorrectionSpecifier(NI->NameSpecifier); 3974 TC.setQualifierDistance(NI->EditDistance); 3975 for (LookupResult::iterator TRD = TmpRes.begin(), 3976 TRDEnd = TmpRes.end(); 3977 TRD != TRDEnd; ++TRD) 3978 TC.addCorrectionDecl(*TRD); 3979 Consumer.addCorrection(TC); 3980 break; 3981 } 3982 case LookupResult::NotFound: 3983 case LookupResult::NotFoundInCurrentInstantiation: 3984 case LookupResult::Ambiguous: 3985 case LookupResult::FoundUnresolvedValue: 3986 break; 3987 } 3988 } 3989 } 3990 } 3991 3992 QualifiedResults.clear(); 3993 } 3994 3995 // No corrections remain... 3996 if (Consumer.empty()) return TypoCorrection(); 3997 3998 TypoResultsMap &BestResults = Consumer.begin()->second; 3999 ED = TypoCorrection::NormalizeEditDistance(Consumer.begin()->first); 4000 4001 if (ED > 0 && Typo->getName().size() / ED < 3) { 4002 // If this was an unqualified lookup and we believe the callback 4003 // object wouldn't have filtered out possible corrections, note 4004 // that no correction was found. 4005 if (IsUnqualifiedLookup && !ValidatingCallback) 4006 (void)UnqualifiedTyposCorrected[Typo]; 4007 4008 return TypoCorrection(); 4009 } 4010 4011 // If only a single name remains, return that result. 4012 if (BestResults.size() == 1) { 4013 const llvm::StringMapEntry<TypoCorrection> &Correction = *(BestResults.begin()); 4014 const TypoCorrection &Result = Correction.second; 4015 4016 // Don't correct to a keyword that's the same as the typo; the keyword 4017 // wasn't actually in scope. 4018 if (ED == 0 && Result.isKeyword()) return TypoCorrection(); 4019 4020 // Record the correction for unqualified lookup. 4021 if (IsUnqualifiedLookup) 4022 UnqualifiedTyposCorrected[Typo] = Result; 4023 4024 return Result; 4025 } 4026 else if (BestResults.size() > 1 4027 // Ugly hack equivalent to CTC == CTC_ObjCMessageReceiver; 4028 // WantObjCSuper is only true for CTC_ObjCMessageReceiver and for 4029 // some instances of CTC_Unknown, while WantRemainingKeywords is true 4030 // for CTC_Unknown but not for CTC_ObjCMessageReceiver. 4031 && CCC.WantObjCSuper && !CCC.WantRemainingKeywords 4032 && BestResults["super"].isKeyword()) { 4033 // Prefer 'super' when we're completing in a message-receiver 4034 // context. 4035 4036 // Don't correct to a keyword that's the same as the typo; the keyword 4037 // wasn't actually in scope. 4038 if (ED == 0) return TypoCorrection(); 4039 4040 // Record the correction for unqualified lookup. 4041 if (IsUnqualifiedLookup) 4042 UnqualifiedTyposCorrected[Typo] = BestResults["super"]; 4043 4044 return BestResults["super"]; 4045 } 4046 4047 // If this was an unqualified lookup and we believe the callback object did 4048 // not filter out possible corrections, note that no correction was found. 4049 if (IsUnqualifiedLookup && !ValidatingCallback) 4050 (void)UnqualifiedTyposCorrected[Typo]; 4051 4052 return TypoCorrection(); 4053 } 4054 4055 void TypoCorrection::addCorrectionDecl(NamedDecl *CDecl) { 4056 if (!CDecl) return; 4057 4058 if (isKeyword()) 4059 CorrectionDecls.clear(); 4060 4061 CorrectionDecls.push_back(CDecl); 4062 4063 if (!CorrectionName) 4064 CorrectionName = CDecl->getDeclName(); 4065 } 4066 4067 std::string TypoCorrection::getAsString(const LangOptions &LO) const { 4068 if (CorrectionNameSpec) { 4069 std::string tmpBuffer; 4070 llvm::raw_string_ostream PrefixOStream(tmpBuffer); 4071 CorrectionNameSpec->print(PrefixOStream, PrintingPolicy(LO)); 4072 CorrectionName.printName(PrefixOStream); 4073 return PrefixOStream.str(); 4074 } 4075 4076 return CorrectionName.getAsString(); 4077 } 4078