SemaLookup.cpp revision 243830
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 51using namespace clang; 52using namespace sema; 53 54namespace { 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. 212static 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 286void 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 308void 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 326void LookupResult::deletePaths(CXXBasePaths *Paths) { 327 delete Paths; 328} 329 330static NamedDecl *getVisibleDecl(NamedDecl *D); 331 332NamedDecl *LookupResult::getAcceptableDeclSlow(NamedDecl *D) const { 333 return getVisibleDecl(D); 334} 335 336/// Resolves the result kind of this lookup. 337void 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 452void 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 460void LookupResult::setAmbiguousBaseSubobjects(CXXBasePaths &P) { 461 Paths = new CXXBasePaths; 462 Paths->swap(P); 463 addDeclsFromBasePaths(*Paths); 464 resolveKind(); 465 setAmbiguous(AmbiguousBaseSubobjects); 466} 467 468void LookupResult::setAmbiguousBaseSubobjectTypes(CXXBasePaths &P) { 469 Paths = new CXXBasePaths; 470 Paths->swap(P); 471 addDeclsFromBasePaths(*Paths); 472 resolveKind(); 473 setAmbiguous(AmbiguousBaseSubobjectTypes); 474} 475 476void 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. 489static 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. 531static 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 545void 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. 578static 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. 596static 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. 649static 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.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. 742static bool 743CppNamespaceLookup(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 765static 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. 778static 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 840bool 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 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 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. 1066static 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 [in,out] R Specifies the lookup to perform (e.g., the name to 1104/// look up and the lookup kind), and is updated with the results of lookup 1105/// including zero or more declarations and possibly additional information 1106/// used to diagnose ambiguities. 1107/// 1108/// @returns \c true if lookup succeeded and false otherwise. 1109bool Sema::LookupName(LookupResult &R, Scope *S, bool AllowBuiltinCreation) { 1110 DeclarationName Name = R.getLookupName(); 1111 if (!Name) return false; 1112 1113 LookupNameKind NameKind = R.getLookupKind(); 1114 1115 if (!getLangOpts().CPlusPlus) { 1116 // Unqualified name lookup in C/Objective-C is purely lexical, so 1117 // search in the declarations attached to the name. 1118 if (NameKind == Sema::LookupRedeclarationWithLinkage) { 1119 // Find the nearest non-transparent declaration scope. 1120 while (!(S->getFlags() & Scope::DeclScope) || 1121 (S->getEntity() && 1122 static_cast<DeclContext *>(S->getEntity()) 1123 ->isTransparentContext())) 1124 S = S->getParent(); 1125 } 1126 1127 unsigned IDNS = R.getIdentifierNamespace(); 1128 1129 // Scan up the scope chain looking for a decl that matches this 1130 // identifier that is in the appropriate namespace. This search 1131 // should not take long, as shadowing of names is uncommon, and 1132 // deep shadowing is extremely uncommon. 1133 bool LeftStartingScope = false; 1134 1135 for (IdentifierResolver::iterator I = IdResolver.begin(Name), 1136 IEnd = IdResolver.end(); 1137 I != IEnd; ++I) 1138 if ((*I)->isInIdentifierNamespace(IDNS)) { 1139 if (NameKind == LookupRedeclarationWithLinkage) { 1140 // Determine whether this (or a previous) declaration is 1141 // out-of-scope. 1142 if (!LeftStartingScope && !S->isDeclScope(*I)) 1143 LeftStartingScope = true; 1144 1145 // If we found something outside of our starting scope that 1146 // does not have linkage, skip it. 1147 if (LeftStartingScope && !((*I)->hasLinkage())) 1148 continue; 1149 } 1150 else if (NameKind == LookupObjCImplicitSelfParam && 1151 !isa<ImplicitParamDecl>(*I)) 1152 continue; 1153 1154 // If this declaration is module-private and it came from an AST 1155 // file, we can't see it. 1156 NamedDecl *D = R.isHiddenDeclarationVisible()? *I : getVisibleDecl(*I); 1157 if (!D) 1158 continue; 1159 1160 R.addDecl(D); 1161 1162 // Check whether there are any other declarations with the same name 1163 // and in the same scope. 1164 if (I != IEnd) { 1165 // Find the scope in which this declaration was declared (if it 1166 // actually exists in a Scope). 1167 while (S && !S->isDeclScope(D)) 1168 S = S->getParent(); 1169 1170 // If the scope containing the declaration is the translation unit, 1171 // then we'll need to perform our checks based on the matching 1172 // DeclContexts rather than matching scopes. 1173 if (S && isNamespaceOrTranslationUnitScope(S)) 1174 S = 0; 1175 1176 // Compute the DeclContext, if we need it. 1177 DeclContext *DC = 0; 1178 if (!S) 1179 DC = (*I)->getDeclContext()->getRedeclContext(); 1180 1181 IdentifierResolver::iterator LastI = I; 1182 for (++LastI; LastI != IEnd; ++LastI) { 1183 if (S) { 1184 // Match based on scope. 1185 if (!S->isDeclScope(*LastI)) 1186 break; 1187 } else { 1188 // Match based on DeclContext. 1189 DeclContext *LastDC 1190 = (*LastI)->getDeclContext()->getRedeclContext(); 1191 if (!LastDC->Equals(DC)) 1192 break; 1193 } 1194 1195 // If the declaration isn't in the right namespace, skip it. 1196 if (!(*LastI)->isInIdentifierNamespace(IDNS)) 1197 continue; 1198 1199 D = R.isHiddenDeclarationVisible()? *LastI : getVisibleDecl(*LastI); 1200 if (D) 1201 R.addDecl(D); 1202 } 1203 1204 R.resolveKind(); 1205 } 1206 return true; 1207 } 1208 } else { 1209 // Perform C++ unqualified name lookup. 1210 if (CppLookupName(R, S)) 1211 return true; 1212 } 1213 1214 // If we didn't find a use of this identifier, and if the identifier 1215 // corresponds to a compiler builtin, create the decl object for the builtin 1216 // now, injecting it into translation unit scope, and return it. 1217 if (AllowBuiltinCreation && LookupBuiltin(*this, R)) 1218 return true; 1219 1220 // If we didn't find a use of this identifier, the ExternalSource 1221 // may be able to handle the situation. 1222 // Note: some lookup failures are expected! 1223 // See e.g. R.isForRedeclaration(). 1224 return (ExternalSource && ExternalSource->LookupUnqualified(R, S)); 1225} 1226 1227/// @brief Perform qualified name lookup in the namespaces nominated by 1228/// using directives by the given context. 1229/// 1230/// C++98 [namespace.qual]p2: 1231/// Given X::m (where X is a user-declared namespace), or given \::m 1232/// (where X is the global namespace), let S be the set of all 1233/// declarations of m in X and in the transitive closure of all 1234/// namespaces nominated by using-directives in X and its used 1235/// namespaces, except that using-directives are ignored in any 1236/// namespace, including X, directly containing one or more 1237/// declarations of m. No namespace is searched more than once in 1238/// the lookup of a name. If S is the empty set, the program is 1239/// ill-formed. Otherwise, if S has exactly one member, or if the 1240/// context of the reference is a using-declaration 1241/// (namespace.udecl), S is the required set of declarations of 1242/// m. Otherwise if the use of m is not one that allows a unique 1243/// declaration to be chosen from S, the program is ill-formed. 1244/// 1245/// C++98 [namespace.qual]p5: 1246/// During the lookup of a qualified namespace member name, if the 1247/// lookup finds more than one declaration of the member, and if one 1248/// declaration introduces a class name or enumeration name and the 1249/// other declarations either introduce the same object, the same 1250/// enumerator or a set of functions, the non-type name hides the 1251/// class or enumeration name if and only if the declarations are 1252/// from the same namespace; otherwise (the declarations are from 1253/// different namespaces), the program is ill-formed. 1254static bool LookupQualifiedNameInUsingDirectives(Sema &S, LookupResult &R, 1255 DeclContext *StartDC) { 1256 assert(StartDC->isFileContext() && "start context is not a file context"); 1257 1258 DeclContext::udir_iterator I = StartDC->using_directives_begin(); 1259 DeclContext::udir_iterator E = StartDC->using_directives_end(); 1260 1261 if (I == E) return false; 1262 1263 // We have at least added all these contexts to the queue. 1264 llvm::SmallPtrSet<DeclContext*, 8> Visited; 1265 Visited.insert(StartDC); 1266 1267 // We have not yet looked into these namespaces, much less added 1268 // their "using-children" to the queue. 1269 SmallVector<NamespaceDecl*, 8> Queue; 1270 1271 // We have already looked into the initial namespace; seed the queue 1272 // with its using-children. 1273 for (; I != E; ++I) { 1274 NamespaceDecl *ND = (*I)->getNominatedNamespace()->getOriginalNamespace(); 1275 if (Visited.insert(ND)) 1276 Queue.push_back(ND); 1277 } 1278 1279 // The easiest way to implement the restriction in [namespace.qual]p5 1280 // is to check whether any of the individual results found a tag 1281 // and, if so, to declare an ambiguity if the final result is not 1282 // a tag. 1283 bool FoundTag = false; 1284 bool FoundNonTag = false; 1285 1286 LookupResult LocalR(LookupResult::Temporary, R); 1287 1288 bool Found = false; 1289 while (!Queue.empty()) { 1290 NamespaceDecl *ND = Queue.back(); 1291 Queue.pop_back(); 1292 1293 // We go through some convolutions here to avoid copying results 1294 // between LookupResults. 1295 bool UseLocal = !R.empty(); 1296 LookupResult &DirectR = UseLocal ? LocalR : R; 1297 bool FoundDirect = LookupDirect(S, DirectR, ND); 1298 1299 if (FoundDirect) { 1300 // First do any local hiding. 1301 DirectR.resolveKind(); 1302 1303 // If the local result is a tag, remember that. 1304 if (DirectR.isSingleTagDecl()) 1305 FoundTag = true; 1306 else 1307 FoundNonTag = true; 1308 1309 // Append the local results to the total results if necessary. 1310 if (UseLocal) { 1311 R.addAllDecls(LocalR); 1312 LocalR.clear(); 1313 } 1314 } 1315 1316 // If we find names in this namespace, ignore its using directives. 1317 if (FoundDirect) { 1318 Found = true; 1319 continue; 1320 } 1321 1322 for (llvm::tie(I,E) = ND->getUsingDirectives(); I != E; ++I) { 1323 NamespaceDecl *Nom = (*I)->getNominatedNamespace(); 1324 if (Visited.insert(Nom)) 1325 Queue.push_back(Nom); 1326 } 1327 } 1328 1329 if (Found) { 1330 if (FoundTag && FoundNonTag) 1331 R.setAmbiguousQualifiedTagHiding(); 1332 else 1333 R.resolveKind(); 1334 } 1335 1336 return Found; 1337} 1338 1339/// \brief Callback that looks for any member of a class with the given name. 1340static bool LookupAnyMember(const CXXBaseSpecifier *Specifier, 1341 CXXBasePath &Path, 1342 void *Name) { 1343 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 1344 1345 DeclarationName N = DeclarationName::getFromOpaquePtr(Name); 1346 Path.Decls = BaseRecord->lookup(N); 1347 return Path.Decls.first != Path.Decls.second; 1348} 1349 1350/// \brief Determine whether the given set of member declarations contains only 1351/// static members, nested types, and enumerators. 1352template<typename InputIterator> 1353static bool HasOnlyStaticMembers(InputIterator First, InputIterator Last) { 1354 Decl *D = (*First)->getUnderlyingDecl(); 1355 if (isa<VarDecl>(D) || isa<TypeDecl>(D) || isa<EnumConstantDecl>(D)) 1356 return true; 1357 1358 if (isa<CXXMethodDecl>(D)) { 1359 // Determine whether all of the methods are static. 1360 bool AllMethodsAreStatic = true; 1361 for(; First != Last; ++First) { 1362 D = (*First)->getUnderlyingDecl(); 1363 1364 if (!isa<CXXMethodDecl>(D)) { 1365 assert(isa<TagDecl>(D) && "Non-function must be a tag decl"); 1366 break; 1367 } 1368 1369 if (!cast<CXXMethodDecl>(D)->isStatic()) { 1370 AllMethodsAreStatic = false; 1371 break; 1372 } 1373 } 1374 1375 if (AllMethodsAreStatic) 1376 return true; 1377 } 1378 1379 return false; 1380} 1381 1382/// \brief Perform qualified name lookup into a given context. 1383/// 1384/// Qualified name lookup (C++ [basic.lookup.qual]) is used to find 1385/// names when the context of those names is explicit specified, e.g., 1386/// "std::vector" or "x->member", or as part of unqualified name lookup. 1387/// 1388/// Different lookup criteria can find different names. For example, a 1389/// particular scope can have both a struct and a function of the same 1390/// name, and each can be found by certain lookup criteria. For more 1391/// information about lookup criteria, see the documentation for the 1392/// class LookupCriteria. 1393/// 1394/// \param R captures both the lookup criteria and any lookup results found. 1395/// 1396/// \param LookupCtx The context in which qualified name lookup will 1397/// search. If the lookup criteria permits, name lookup may also search 1398/// in the parent contexts or (for C++ classes) base classes. 1399/// 1400/// \param InUnqualifiedLookup true if this is qualified name lookup that 1401/// occurs as part of unqualified name lookup. 1402/// 1403/// \returns true if lookup succeeded, false if it failed. 1404bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx, 1405 bool InUnqualifiedLookup) { 1406 assert(LookupCtx && "Sema::LookupQualifiedName requires a lookup context"); 1407 1408 if (!R.getLookupName()) 1409 return false; 1410 1411 // Make sure that the declaration context is complete. 1412 assert((!isa<TagDecl>(LookupCtx) || 1413 LookupCtx->isDependentContext() || 1414 cast<TagDecl>(LookupCtx)->isCompleteDefinition() || 1415 cast<TagDecl>(LookupCtx)->isBeingDefined()) && 1416 "Declaration context must already be complete!"); 1417 1418 // Perform qualified name lookup into the LookupCtx. 1419 if (LookupDirect(*this, R, LookupCtx)) { 1420 R.resolveKind(); 1421 if (isa<CXXRecordDecl>(LookupCtx)) 1422 R.setNamingClass(cast<CXXRecordDecl>(LookupCtx)); 1423 return true; 1424 } 1425 1426 // Don't descend into implied contexts for redeclarations. 1427 // C++98 [namespace.qual]p6: 1428 // In a declaration for a namespace member in which the 1429 // declarator-id is a qualified-id, given that the qualified-id 1430 // for the namespace member has the form 1431 // nested-name-specifier unqualified-id 1432 // the unqualified-id shall name a member of the namespace 1433 // designated by the nested-name-specifier. 1434 // See also [class.mfct]p5 and [class.static.data]p2. 1435 if (R.isForRedeclaration()) 1436 return false; 1437 1438 // If this is a namespace, look it up in the implied namespaces. 1439 if (LookupCtx->isFileContext()) 1440 return LookupQualifiedNameInUsingDirectives(*this, R, LookupCtx); 1441 1442 // If this isn't a C++ class, we aren't allowed to look into base 1443 // classes, we're done. 1444 CXXRecordDecl *LookupRec = dyn_cast<CXXRecordDecl>(LookupCtx); 1445 if (!LookupRec || !LookupRec->getDefinition()) 1446 return false; 1447 1448 // If we're performing qualified name lookup into a dependent class, 1449 // then we are actually looking into a current instantiation. If we have any 1450 // dependent base classes, then we either have to delay lookup until 1451 // template instantiation time (at which point all bases will be available) 1452 // or we have to fail. 1453 if (!InUnqualifiedLookup && LookupRec->isDependentContext() && 1454 LookupRec->hasAnyDependentBases()) { 1455 R.setNotFoundInCurrentInstantiation(); 1456 return false; 1457 } 1458 1459 // Perform lookup into our base classes. 1460 CXXBasePaths Paths; 1461 Paths.setOrigin(LookupRec); 1462 1463 // Look for this member in our base classes 1464 CXXRecordDecl::BaseMatchesCallback *BaseCallback = 0; 1465 switch (R.getLookupKind()) { 1466 case LookupObjCImplicitSelfParam: 1467 case LookupOrdinaryName: 1468 case LookupMemberName: 1469 case LookupRedeclarationWithLinkage: 1470 BaseCallback = &CXXRecordDecl::FindOrdinaryMember; 1471 break; 1472 1473 case LookupTagName: 1474 BaseCallback = &CXXRecordDecl::FindTagMember; 1475 break; 1476 1477 case LookupAnyName: 1478 BaseCallback = &LookupAnyMember; 1479 break; 1480 1481 case LookupUsingDeclName: 1482 // This lookup is for redeclarations only. 1483 1484 case LookupOperatorName: 1485 case LookupNamespaceName: 1486 case LookupObjCProtocolName: 1487 case LookupLabel: 1488 // These lookups will never find a member in a C++ class (or base class). 1489 return false; 1490 1491 case LookupNestedNameSpecifierName: 1492 BaseCallback = &CXXRecordDecl::FindNestedNameSpecifierMember; 1493 break; 1494 } 1495 1496 if (!LookupRec->lookupInBases(BaseCallback, 1497 R.getLookupName().getAsOpaquePtr(), Paths)) 1498 return false; 1499 1500 R.setNamingClass(LookupRec); 1501 1502 // C++ [class.member.lookup]p2: 1503 // [...] If the resulting set of declarations are not all from 1504 // sub-objects of the same type, or the set has a nonstatic member 1505 // and includes members from distinct sub-objects, there is an 1506 // ambiguity and the program is ill-formed. Otherwise that set is 1507 // the result of the lookup. 1508 QualType SubobjectType; 1509 int SubobjectNumber = 0; 1510 AccessSpecifier SubobjectAccess = AS_none; 1511 1512 for (CXXBasePaths::paths_iterator Path = Paths.begin(), PathEnd = Paths.end(); 1513 Path != PathEnd; ++Path) { 1514 const CXXBasePathElement &PathElement = Path->back(); 1515 1516 // Pick the best (i.e. most permissive i.e. numerically lowest) access 1517 // across all paths. 1518 SubobjectAccess = std::min(SubobjectAccess, Path->Access); 1519 1520 // Determine whether we're looking at a distinct sub-object or not. 1521 if (SubobjectType.isNull()) { 1522 // This is the first subobject we've looked at. Record its type. 1523 SubobjectType = Context.getCanonicalType(PathElement.Base->getType()); 1524 SubobjectNumber = PathElement.SubobjectNumber; 1525 continue; 1526 } 1527 1528 if (SubobjectType 1529 != Context.getCanonicalType(PathElement.Base->getType())) { 1530 // We found members of the given name in two subobjects of 1531 // different types. If the declaration sets aren't the same, this 1532 // this lookup is ambiguous. 1533 if (HasOnlyStaticMembers(Path->Decls.first, Path->Decls.second)) { 1534 CXXBasePaths::paths_iterator FirstPath = Paths.begin(); 1535 DeclContext::lookup_iterator FirstD = FirstPath->Decls.first; 1536 DeclContext::lookup_iterator CurrentD = Path->Decls.first; 1537 1538 while (FirstD != FirstPath->Decls.second && 1539 CurrentD != Path->Decls.second) { 1540 if ((*FirstD)->getUnderlyingDecl()->getCanonicalDecl() != 1541 (*CurrentD)->getUnderlyingDecl()->getCanonicalDecl()) 1542 break; 1543 1544 ++FirstD; 1545 ++CurrentD; 1546 } 1547 1548 if (FirstD == FirstPath->Decls.second && 1549 CurrentD == Path->Decls.second) 1550 continue; 1551 } 1552 1553 R.setAmbiguousBaseSubobjectTypes(Paths); 1554 return true; 1555 } 1556 1557 if (SubobjectNumber != PathElement.SubobjectNumber) { 1558 // We have a different subobject of the same type. 1559 1560 // C++ [class.member.lookup]p5: 1561 // A static member, a nested type or an enumerator defined in 1562 // a base class T can unambiguously be found even if an object 1563 // has more than one base class subobject of type T. 1564 if (HasOnlyStaticMembers(Path->Decls.first, Path->Decls.second)) 1565 continue; 1566 1567 // We have found a nonstatic member name in multiple, distinct 1568 // subobjects. Name lookup is ambiguous. 1569 R.setAmbiguousBaseSubobjects(Paths); 1570 return true; 1571 } 1572 } 1573 1574 // Lookup in a base class succeeded; return these results. 1575 1576 DeclContext::lookup_iterator I, E; 1577 for (llvm::tie(I,E) = Paths.front().Decls; I != E; ++I) { 1578 NamedDecl *D = *I; 1579 AccessSpecifier AS = CXXRecordDecl::MergeAccess(SubobjectAccess, 1580 D->getAccess()); 1581 R.addDecl(D, AS); 1582 } 1583 R.resolveKind(); 1584 return true; 1585} 1586 1587/// @brief Performs name lookup for a name that was parsed in the 1588/// source code, and may contain a C++ scope specifier. 1589/// 1590/// This routine is a convenience routine meant to be called from 1591/// contexts that receive a name and an optional C++ scope specifier 1592/// (e.g., "N::M::x"). It will then perform either qualified or 1593/// unqualified name lookup (with LookupQualifiedName or LookupName, 1594/// respectively) on the given name and return those results. 1595/// 1596/// @param S The scope from which unqualified name lookup will 1597/// begin. 1598/// 1599/// @param SS An optional C++ scope-specifier, e.g., "::N::M". 1600/// 1601/// @param EnteringContext Indicates whether we are going to enter the 1602/// context of the scope-specifier SS (if present). 1603/// 1604/// @returns True if any decls were found (but possibly ambiguous) 1605bool Sema::LookupParsedName(LookupResult &R, Scope *S, CXXScopeSpec *SS, 1606 bool AllowBuiltinCreation, bool EnteringContext) { 1607 if (SS && SS->isInvalid()) { 1608 // When the scope specifier is invalid, don't even look for 1609 // anything. 1610 return false; 1611 } 1612 1613 if (SS && SS->isSet()) { 1614 if (DeclContext *DC = computeDeclContext(*SS, EnteringContext)) { 1615 // We have resolved the scope specifier to a particular declaration 1616 // contex, and will perform name lookup in that context. 1617 if (!DC->isDependentContext() && RequireCompleteDeclContext(*SS, DC)) 1618 return false; 1619 1620 R.setContextRange(SS->getRange()); 1621 return LookupQualifiedName(R, DC); 1622 } 1623 1624 // We could not resolve the scope specified to a specific declaration 1625 // context, which means that SS refers to an unknown specialization. 1626 // Name lookup can't find anything in this case. 1627 R.setNotFoundInCurrentInstantiation(); 1628 R.setContextRange(SS->getRange()); 1629 return false; 1630 } 1631 1632 // Perform unqualified name lookup starting in the given scope. 1633 return LookupName(R, S, AllowBuiltinCreation); 1634} 1635 1636 1637/// \brief Produce a diagnostic describing the ambiguity that resulted 1638/// from name lookup. 1639/// 1640/// \param Result The result of the ambiguous lookup to be diagnosed. 1641/// 1642/// \returns true 1643bool Sema::DiagnoseAmbiguousLookup(LookupResult &Result) { 1644 assert(Result.isAmbiguous() && "Lookup result must be ambiguous"); 1645 1646 DeclarationName Name = Result.getLookupName(); 1647 SourceLocation NameLoc = Result.getNameLoc(); 1648 SourceRange LookupRange = Result.getContextRange(); 1649 1650 switch (Result.getAmbiguityKind()) { 1651 case LookupResult::AmbiguousBaseSubobjects: { 1652 CXXBasePaths *Paths = Result.getBasePaths(); 1653 QualType SubobjectType = Paths->front().back().Base->getType(); 1654 Diag(NameLoc, diag::err_ambiguous_member_multiple_subobjects) 1655 << Name << SubobjectType << getAmbiguousPathsDisplayString(*Paths) 1656 << LookupRange; 1657 1658 DeclContext::lookup_iterator Found = Paths->front().Decls.first; 1659 while (isa<CXXMethodDecl>(*Found) && 1660 cast<CXXMethodDecl>(*Found)->isStatic()) 1661 ++Found; 1662 1663 Diag((*Found)->getLocation(), diag::note_ambiguous_member_found); 1664 1665 return true; 1666 } 1667 1668 case LookupResult::AmbiguousBaseSubobjectTypes: { 1669 Diag(NameLoc, diag::err_ambiguous_member_multiple_subobject_types) 1670 << Name << LookupRange; 1671 1672 CXXBasePaths *Paths = Result.getBasePaths(); 1673 std::set<Decl *> DeclsPrinted; 1674 for (CXXBasePaths::paths_iterator Path = Paths->begin(), 1675 PathEnd = Paths->end(); 1676 Path != PathEnd; ++Path) { 1677 Decl *D = *Path->Decls.first; 1678 if (DeclsPrinted.insert(D).second) 1679 Diag(D->getLocation(), diag::note_ambiguous_member_found); 1680 } 1681 1682 return true; 1683 } 1684 1685 case LookupResult::AmbiguousTagHiding: { 1686 Diag(NameLoc, diag::err_ambiguous_tag_hiding) << Name << LookupRange; 1687 1688 llvm::SmallPtrSet<NamedDecl*,8> TagDecls; 1689 1690 LookupResult::iterator DI, DE = Result.end(); 1691 for (DI = Result.begin(); DI != DE; ++DI) 1692 if (TagDecl *TD = dyn_cast<TagDecl>(*DI)) { 1693 TagDecls.insert(TD); 1694 Diag(TD->getLocation(), diag::note_hidden_tag); 1695 } 1696 1697 for (DI = Result.begin(); DI != DE; ++DI) 1698 if (!isa<TagDecl>(*DI)) 1699 Diag((*DI)->getLocation(), diag::note_hiding_object); 1700 1701 // For recovery purposes, go ahead and implement the hiding. 1702 LookupResult::Filter F = Result.makeFilter(); 1703 while (F.hasNext()) { 1704 if (TagDecls.count(F.next())) 1705 F.erase(); 1706 } 1707 F.done(); 1708 1709 return true; 1710 } 1711 1712 case LookupResult::AmbiguousReference: { 1713 Diag(NameLoc, diag::err_ambiguous_reference) << Name << LookupRange; 1714 1715 LookupResult::iterator DI = Result.begin(), DE = Result.end(); 1716 for (; DI != DE; ++DI) 1717 Diag((*DI)->getLocation(), diag::note_ambiguous_candidate) << *DI; 1718 1719 return true; 1720 } 1721 } 1722 1723 llvm_unreachable("unknown ambiguity kind"); 1724} 1725 1726namespace { 1727 struct AssociatedLookup { 1728 AssociatedLookup(Sema &S, SourceLocation InstantiationLoc, 1729 Sema::AssociatedNamespaceSet &Namespaces, 1730 Sema::AssociatedClassSet &Classes) 1731 : S(S), Namespaces(Namespaces), Classes(Classes), 1732 InstantiationLoc(InstantiationLoc) { 1733 } 1734 1735 Sema &S; 1736 Sema::AssociatedNamespaceSet &Namespaces; 1737 Sema::AssociatedClassSet &Classes; 1738 SourceLocation InstantiationLoc; 1739 }; 1740} 1741 1742static void 1743addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType T); 1744 1745static void CollectEnclosingNamespace(Sema::AssociatedNamespaceSet &Namespaces, 1746 DeclContext *Ctx) { 1747 // Add the associated namespace for this class. 1748 1749 // We don't use DeclContext::getEnclosingNamespaceContext() as this may 1750 // be a locally scoped record. 1751 1752 // We skip out of inline namespaces. The innermost non-inline namespace 1753 // contains all names of all its nested inline namespaces anyway, so we can 1754 // replace the entire inline namespace tree with its root. 1755 while (Ctx->isRecord() || Ctx->isTransparentContext() || 1756 Ctx->isInlineNamespace()) 1757 Ctx = Ctx->getParent(); 1758 1759 if (Ctx->isFileContext()) 1760 Namespaces.insert(Ctx->getPrimaryContext()); 1761} 1762 1763// \brief Add the associated classes and namespaces for argument-dependent 1764// lookup that involves a template argument (C++ [basic.lookup.koenig]p2). 1765static void 1766addAssociatedClassesAndNamespaces(AssociatedLookup &Result, 1767 const TemplateArgument &Arg) { 1768 // C++ [basic.lookup.koenig]p2, last bullet: 1769 // -- [...] ; 1770 switch (Arg.getKind()) { 1771 case TemplateArgument::Null: 1772 break; 1773 1774 case TemplateArgument::Type: 1775 // [...] the namespaces and classes associated with the types of the 1776 // template arguments provided for template type parameters (excluding 1777 // template template parameters) 1778 addAssociatedClassesAndNamespaces(Result, Arg.getAsType()); 1779 break; 1780 1781 case TemplateArgument::Template: 1782 case TemplateArgument::TemplateExpansion: { 1783 // [...] the namespaces in which any template template arguments are 1784 // defined; and the classes in which any member templates used as 1785 // template template arguments are defined. 1786 TemplateName Template = Arg.getAsTemplateOrTemplatePattern(); 1787 if (ClassTemplateDecl *ClassTemplate 1788 = dyn_cast<ClassTemplateDecl>(Template.getAsTemplateDecl())) { 1789 DeclContext *Ctx = ClassTemplate->getDeclContext(); 1790 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx)) 1791 Result.Classes.insert(EnclosingClass); 1792 // Add the associated namespace for this class. 1793 CollectEnclosingNamespace(Result.Namespaces, Ctx); 1794 } 1795 break; 1796 } 1797 1798 case TemplateArgument::Declaration: 1799 case TemplateArgument::Integral: 1800 case TemplateArgument::Expression: 1801 case TemplateArgument::NullPtr: 1802 // [Note: non-type template arguments do not contribute to the set of 1803 // associated namespaces. ] 1804 break; 1805 1806 case TemplateArgument::Pack: 1807 for (TemplateArgument::pack_iterator P = Arg.pack_begin(), 1808 PEnd = Arg.pack_end(); 1809 P != PEnd; ++P) 1810 addAssociatedClassesAndNamespaces(Result, *P); 1811 break; 1812 } 1813} 1814 1815// \brief Add the associated classes and namespaces for 1816// argument-dependent lookup with an argument of class type 1817// (C++ [basic.lookup.koenig]p2). 1818static void 1819addAssociatedClassesAndNamespaces(AssociatedLookup &Result, 1820 CXXRecordDecl *Class) { 1821 1822 // Just silently ignore anything whose name is __va_list_tag. 1823 if (Class->getDeclName() == Result.S.VAListTagName) 1824 return; 1825 1826 // C++ [basic.lookup.koenig]p2: 1827 // [...] 1828 // -- If T is a class type (including unions), its associated 1829 // classes are: the class itself; the class of which it is a 1830 // member, if any; and its direct and indirect base 1831 // classes. Its associated namespaces are the namespaces in 1832 // which its associated classes are defined. 1833 1834 // Add the class of which it is a member, if any. 1835 DeclContext *Ctx = Class->getDeclContext(); 1836 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx)) 1837 Result.Classes.insert(EnclosingClass); 1838 // Add the associated namespace for this class. 1839 CollectEnclosingNamespace(Result.Namespaces, Ctx); 1840 1841 // Add the class itself. If we've already seen this class, we don't 1842 // need to visit base classes. 1843 if (!Result.Classes.insert(Class)) 1844 return; 1845 1846 // -- If T is a template-id, its associated namespaces and classes are 1847 // the namespace in which the template is defined; for member 1848 // templates, the member template's class; the namespaces and classes 1849 // associated with the types of the template arguments provided for 1850 // template type parameters (excluding template template parameters); the 1851 // namespaces in which any template template arguments are defined; and 1852 // the classes in which any member templates used as template template 1853 // arguments are defined. [Note: non-type template arguments do not 1854 // contribute to the set of associated namespaces. ] 1855 if (ClassTemplateSpecializationDecl *Spec 1856 = dyn_cast<ClassTemplateSpecializationDecl>(Class)) { 1857 DeclContext *Ctx = Spec->getSpecializedTemplate()->getDeclContext(); 1858 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx)) 1859 Result.Classes.insert(EnclosingClass); 1860 // Add the associated namespace for this class. 1861 CollectEnclosingNamespace(Result.Namespaces, Ctx); 1862 1863 const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs(); 1864 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I) 1865 addAssociatedClassesAndNamespaces(Result, TemplateArgs[I]); 1866 } 1867 1868 // Only recurse into base classes for complete types. 1869 if (!Class->hasDefinition()) { 1870 QualType type = Result.S.Context.getTypeDeclType(Class); 1871 if (Result.S.RequireCompleteType(Result.InstantiationLoc, type, 1872 /*no diagnostic*/ 0)) 1873 return; 1874 } 1875 1876 // Add direct and indirect base classes along with their associated 1877 // namespaces. 1878 SmallVector<CXXRecordDecl *, 32> Bases; 1879 Bases.push_back(Class); 1880 while (!Bases.empty()) { 1881 // Pop this class off the stack. 1882 Class = Bases.back(); 1883 Bases.pop_back(); 1884 1885 // Visit the base classes. 1886 for (CXXRecordDecl::base_class_iterator Base = Class->bases_begin(), 1887 BaseEnd = Class->bases_end(); 1888 Base != BaseEnd; ++Base) { 1889 const RecordType *BaseType = Base->getType()->getAs<RecordType>(); 1890 // In dependent contexts, we do ADL twice, and the first time around, 1891 // the base type might be a dependent TemplateSpecializationType, or a 1892 // TemplateTypeParmType. If that happens, simply ignore it. 1893 // FIXME: If we want to support export, we probably need to add the 1894 // namespace of the template in a TemplateSpecializationType, or even 1895 // the classes and namespaces of known non-dependent arguments. 1896 if (!BaseType) 1897 continue; 1898 CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(BaseType->getDecl()); 1899 if (Result.Classes.insert(BaseDecl)) { 1900 // Find the associated namespace for this base class. 1901 DeclContext *BaseCtx = BaseDecl->getDeclContext(); 1902 CollectEnclosingNamespace(Result.Namespaces, BaseCtx); 1903 1904 // Make sure we visit the bases of this base class. 1905 if (BaseDecl->bases_begin() != BaseDecl->bases_end()) 1906 Bases.push_back(BaseDecl); 1907 } 1908 } 1909 } 1910} 1911 1912// \brief Add the associated classes and namespaces for 1913// argument-dependent lookup with an argument of type T 1914// (C++ [basic.lookup.koenig]p2). 1915static void 1916addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType Ty) { 1917 // C++ [basic.lookup.koenig]p2: 1918 // 1919 // For each argument type T in the function call, there is a set 1920 // of zero or more associated namespaces and a set of zero or more 1921 // associated classes to be considered. The sets of namespaces and 1922 // classes is determined entirely by the types of the function 1923 // arguments (and the namespace of any template template 1924 // argument). Typedef names and using-declarations used to specify 1925 // the types do not contribute to this set. The sets of namespaces 1926 // and classes are determined in the following way: 1927 1928 SmallVector<const Type *, 16> Queue; 1929 const Type *T = Ty->getCanonicalTypeInternal().getTypePtr(); 1930 1931 while (true) { 1932 switch (T->getTypeClass()) { 1933 1934#define TYPE(Class, Base) 1935#define DEPENDENT_TYPE(Class, Base) case Type::Class: 1936#define NON_CANONICAL_TYPE(Class, Base) case Type::Class: 1937#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class: 1938#define ABSTRACT_TYPE(Class, Base) 1939#include "clang/AST/TypeNodes.def" 1940 // T is canonical. We can also ignore dependent types because 1941 // we don't need to do ADL at the definition point, but if we 1942 // wanted to implement template export (or if we find some other 1943 // use for associated classes and namespaces...) this would be 1944 // wrong. 1945 break; 1946 1947 // -- If T is a pointer to U or an array of U, its associated 1948 // namespaces and classes are those associated with U. 1949 case Type::Pointer: 1950 T = cast<PointerType>(T)->getPointeeType().getTypePtr(); 1951 continue; 1952 case Type::ConstantArray: 1953 case Type::IncompleteArray: 1954 case Type::VariableArray: 1955 T = cast<ArrayType>(T)->getElementType().getTypePtr(); 1956 continue; 1957 1958 // -- If T is a fundamental type, its associated sets of 1959 // namespaces and classes are both empty. 1960 case Type::Builtin: 1961 break; 1962 1963 // -- If T is a class type (including unions), its associated 1964 // classes are: the class itself; the class of which it is a 1965 // member, if any; and its direct and indirect base 1966 // classes. Its associated namespaces are the namespaces in 1967 // which its associated classes are defined. 1968 case Type::Record: { 1969 CXXRecordDecl *Class 1970 = cast<CXXRecordDecl>(cast<RecordType>(T)->getDecl()); 1971 addAssociatedClassesAndNamespaces(Result, Class); 1972 break; 1973 } 1974 1975 // -- If T is an enumeration type, its associated namespace is 1976 // the namespace in which it is defined. If it is class 1977 // member, its associated class is the member's class; else 1978 // it has no associated class. 1979 case Type::Enum: { 1980 EnumDecl *Enum = cast<EnumType>(T)->getDecl(); 1981 1982 DeclContext *Ctx = Enum->getDeclContext(); 1983 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx)) 1984 Result.Classes.insert(EnclosingClass); 1985 1986 // Add the associated namespace for this class. 1987 CollectEnclosingNamespace(Result.Namespaces, Ctx); 1988 1989 break; 1990 } 1991 1992 // -- If T is a function type, its associated namespaces and 1993 // classes are those associated with the function parameter 1994 // types and those associated with the return type. 1995 case Type::FunctionProto: { 1996 const FunctionProtoType *Proto = cast<FunctionProtoType>(T); 1997 for (FunctionProtoType::arg_type_iterator Arg = Proto->arg_type_begin(), 1998 ArgEnd = Proto->arg_type_end(); 1999 Arg != ArgEnd; ++Arg) 2000 Queue.push_back(Arg->getTypePtr()); 2001 // fallthrough 2002 } 2003 case Type::FunctionNoProto: { 2004 const FunctionType *FnType = cast<FunctionType>(T); 2005 T = FnType->getResultType().getTypePtr(); 2006 continue; 2007 } 2008 2009 // -- If T is a pointer to a member function of a class X, its 2010 // associated namespaces and classes are those associated 2011 // with the function parameter types and return type, 2012 // together with those associated with X. 2013 // 2014 // -- If T is a pointer to a data member of class X, its 2015 // associated namespaces and classes are those associated 2016 // with the member type together with those associated with 2017 // X. 2018 case Type::MemberPointer: { 2019 const MemberPointerType *MemberPtr = cast<MemberPointerType>(T); 2020 2021 // Queue up the class type into which this points. 2022 Queue.push_back(MemberPtr->getClass()); 2023 2024 // And directly continue with the pointee type. 2025 T = MemberPtr->getPointeeType().getTypePtr(); 2026 continue; 2027 } 2028 2029 // As an extension, treat this like a normal pointer. 2030 case Type::BlockPointer: 2031 T = cast<BlockPointerType>(T)->getPointeeType().getTypePtr(); 2032 continue; 2033 2034 // References aren't covered by the standard, but that's such an 2035 // obvious defect that we cover them anyway. 2036 case Type::LValueReference: 2037 case Type::RValueReference: 2038 T = cast<ReferenceType>(T)->getPointeeType().getTypePtr(); 2039 continue; 2040 2041 // These are fundamental types. 2042 case Type::Vector: 2043 case Type::ExtVector: 2044 case Type::Complex: 2045 break; 2046 2047 // If T is an Objective-C object or interface type, or a pointer to an 2048 // object or interface type, the associated namespace is the global 2049 // namespace. 2050 case Type::ObjCObject: 2051 case Type::ObjCInterface: 2052 case Type::ObjCObjectPointer: 2053 Result.Namespaces.insert(Result.S.Context.getTranslationUnitDecl()); 2054 break; 2055 2056 // Atomic types are just wrappers; use the associations of the 2057 // contained type. 2058 case Type::Atomic: 2059 T = cast<AtomicType>(T)->getValueType().getTypePtr(); 2060 continue; 2061 } 2062 2063 if (Queue.empty()) break; 2064 T = Queue.back(); 2065 Queue.pop_back(); 2066 } 2067} 2068 2069/// \brief Find the associated classes and namespaces for 2070/// argument-dependent lookup for a call with the given set of 2071/// arguments. 2072/// 2073/// This routine computes the sets of associated classes and associated 2074/// namespaces searched by argument-dependent lookup 2075/// (C++ [basic.lookup.argdep]) for a given set of arguments. 2076void 2077Sema::FindAssociatedClassesAndNamespaces(SourceLocation InstantiationLoc, 2078 llvm::ArrayRef<Expr *> Args, 2079 AssociatedNamespaceSet &AssociatedNamespaces, 2080 AssociatedClassSet &AssociatedClasses) { 2081 AssociatedNamespaces.clear(); 2082 AssociatedClasses.clear(); 2083 2084 AssociatedLookup Result(*this, InstantiationLoc, 2085 AssociatedNamespaces, AssociatedClasses); 2086 2087 // C++ [basic.lookup.koenig]p2: 2088 // For each argument type T in the function call, there is a set 2089 // of zero or more associated namespaces and a set of zero or more 2090 // associated classes to be considered. The sets of namespaces and 2091 // classes is determined entirely by the types of the function 2092 // arguments (and the namespace of any template template 2093 // argument). 2094 for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) { 2095 Expr *Arg = Args[ArgIdx]; 2096 2097 if (Arg->getType() != Context.OverloadTy) { 2098 addAssociatedClassesAndNamespaces(Result, Arg->getType()); 2099 continue; 2100 } 2101 2102 // [...] In addition, if the argument is the name or address of a 2103 // set of overloaded functions and/or function templates, its 2104 // associated classes and namespaces are the union of those 2105 // associated with each of the members of the set: the namespace 2106 // in which the function or function template is defined and the 2107 // classes and namespaces associated with its (non-dependent) 2108 // parameter types and return type. 2109 Arg = Arg->IgnoreParens(); 2110 if (UnaryOperator *unaryOp = dyn_cast<UnaryOperator>(Arg)) 2111 if (unaryOp->getOpcode() == UO_AddrOf) 2112 Arg = unaryOp->getSubExpr(); 2113 2114 UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Arg); 2115 if (!ULE) continue; 2116 2117 for (UnresolvedSetIterator I = ULE->decls_begin(), E = ULE->decls_end(); 2118 I != E; ++I) { 2119 // Look through any using declarations to find the underlying function. 2120 NamedDecl *Fn = (*I)->getUnderlyingDecl(); 2121 2122 FunctionDecl *FDecl = dyn_cast<FunctionDecl>(Fn); 2123 if (!FDecl) 2124 FDecl = cast<FunctionTemplateDecl>(Fn)->getTemplatedDecl(); 2125 2126 // Add the classes and namespaces associated with the parameter 2127 // types and return type of this function. 2128 addAssociatedClassesAndNamespaces(Result, FDecl->getType()); 2129 } 2130 } 2131} 2132 2133/// IsAcceptableNonMemberOperatorCandidate - Determine whether Fn is 2134/// an acceptable non-member overloaded operator for a call whose 2135/// arguments have types T1 (and, if non-empty, T2). This routine 2136/// implements the check in C++ [over.match.oper]p3b2 concerning 2137/// enumeration types. 2138static bool 2139IsAcceptableNonMemberOperatorCandidate(FunctionDecl *Fn, 2140 QualType T1, QualType T2, 2141 ASTContext &Context) { 2142 if (T1->isDependentType() || (!T2.isNull() && T2->isDependentType())) 2143 return true; 2144 2145 if (T1->isRecordType() || (!T2.isNull() && T2->isRecordType())) 2146 return true; 2147 2148 const FunctionProtoType *Proto = Fn->getType()->getAs<FunctionProtoType>(); 2149 if (Proto->getNumArgs() < 1) 2150 return false; 2151 2152 if (T1->isEnumeralType()) { 2153 QualType ArgType = Proto->getArgType(0).getNonReferenceType(); 2154 if (Context.hasSameUnqualifiedType(T1, ArgType)) 2155 return true; 2156 } 2157 2158 if (Proto->getNumArgs() < 2) 2159 return false; 2160 2161 if (!T2.isNull() && T2->isEnumeralType()) { 2162 QualType ArgType = Proto->getArgType(1).getNonReferenceType(); 2163 if (Context.hasSameUnqualifiedType(T2, ArgType)) 2164 return true; 2165 } 2166 2167 return false; 2168} 2169 2170NamedDecl *Sema::LookupSingleName(Scope *S, DeclarationName Name, 2171 SourceLocation Loc, 2172 LookupNameKind NameKind, 2173 RedeclarationKind Redecl) { 2174 LookupResult R(*this, Name, Loc, NameKind, Redecl); 2175 LookupName(R, S); 2176 return R.getAsSingle<NamedDecl>(); 2177} 2178 2179/// \brief Find the protocol with the given name, if any. 2180ObjCProtocolDecl *Sema::LookupProtocol(IdentifierInfo *II, 2181 SourceLocation IdLoc, 2182 RedeclarationKind Redecl) { 2183 Decl *D = LookupSingleName(TUScope, II, IdLoc, 2184 LookupObjCProtocolName, Redecl); 2185 return cast_or_null<ObjCProtocolDecl>(D); 2186} 2187 2188void Sema::LookupOverloadedOperatorName(OverloadedOperatorKind Op, Scope *S, 2189 QualType T1, QualType T2, 2190 UnresolvedSetImpl &Functions) { 2191 // C++ [over.match.oper]p3: 2192 // -- The set of non-member candidates is the result of the 2193 // unqualified lookup of operator@ in the context of the 2194 // expression according to the usual rules for name lookup in 2195 // unqualified function calls (3.4.2) except that all member 2196 // functions are ignored. However, if no operand has a class 2197 // type, only those non-member functions in the lookup set 2198 // that have a first parameter of type T1 or "reference to 2199 // (possibly cv-qualified) T1", when T1 is an enumeration 2200 // type, or (if there is a right operand) a second parameter 2201 // of type T2 or "reference to (possibly cv-qualified) T2", 2202 // when T2 is an enumeration type, are candidate functions. 2203 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 2204 LookupResult Operators(*this, OpName, SourceLocation(), LookupOperatorName); 2205 LookupName(Operators, S); 2206 2207 assert(!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous"); 2208 2209 if (Operators.empty()) 2210 return; 2211 2212 for (LookupResult::iterator Op = Operators.begin(), OpEnd = Operators.end(); 2213 Op != OpEnd; ++Op) { 2214 NamedDecl *Found = (*Op)->getUnderlyingDecl(); 2215 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Found)) { 2216 if (IsAcceptableNonMemberOperatorCandidate(FD, T1, T2, Context)) 2217 Functions.addDecl(*Op, Op.getAccess()); // FIXME: canonical FD 2218 } else if (FunctionTemplateDecl *FunTmpl 2219 = dyn_cast<FunctionTemplateDecl>(Found)) { 2220 // FIXME: friend operators? 2221 // FIXME: do we need to check IsAcceptableNonMemberOperatorCandidate, 2222 // later? 2223 if (!FunTmpl->getDeclContext()->isRecord()) 2224 Functions.addDecl(*Op, Op.getAccess()); 2225 } 2226 } 2227} 2228 2229Sema::SpecialMemberOverloadResult *Sema::LookupSpecialMember(CXXRecordDecl *RD, 2230 CXXSpecialMember SM, 2231 bool ConstArg, 2232 bool VolatileArg, 2233 bool RValueThis, 2234 bool ConstThis, 2235 bool VolatileThis) { 2236 RD = RD->getDefinition(); 2237 assert((RD && !RD->isBeingDefined()) && 2238 "doing special member lookup into record that isn't fully complete"); 2239 if (RValueThis || ConstThis || VolatileThis) 2240 assert((SM == CXXCopyAssignment || SM == CXXMoveAssignment) && 2241 "constructors and destructors always have unqualified lvalue this"); 2242 if (ConstArg || VolatileArg) 2243 assert((SM != CXXDefaultConstructor && SM != CXXDestructor) && 2244 "parameter-less special members can't have qualified arguments"); 2245 2246 llvm::FoldingSetNodeID ID; 2247 ID.AddPointer(RD); 2248 ID.AddInteger(SM); 2249 ID.AddInteger(ConstArg); 2250 ID.AddInteger(VolatileArg); 2251 ID.AddInteger(RValueThis); 2252 ID.AddInteger(ConstThis); 2253 ID.AddInteger(VolatileThis); 2254 2255 void *InsertPoint; 2256 SpecialMemberOverloadResult *Result = 2257 SpecialMemberCache.FindNodeOrInsertPos(ID, InsertPoint); 2258 2259 // This was already cached 2260 if (Result) 2261 return Result; 2262 2263 Result = BumpAlloc.Allocate<SpecialMemberOverloadResult>(); 2264 Result = new (Result) SpecialMemberOverloadResult(ID); 2265 SpecialMemberCache.InsertNode(Result, InsertPoint); 2266 2267 if (SM == CXXDestructor) { 2268 if (!RD->hasDeclaredDestructor()) 2269 DeclareImplicitDestructor(RD); 2270 CXXDestructorDecl *DD = RD->getDestructor(); 2271 assert(DD && "record without a destructor"); 2272 Result->setMethod(DD); 2273 Result->setKind(DD->isDeleted() ? 2274 SpecialMemberOverloadResult::NoMemberOrDeleted : 2275 SpecialMemberOverloadResult::Success); 2276 return Result; 2277 } 2278 2279 // Prepare for overload resolution. Here we construct a synthetic argument 2280 // if necessary and make sure that implicit functions are declared. 2281 CanQualType CanTy = Context.getCanonicalType(Context.getTagDeclType(RD)); 2282 DeclarationName Name; 2283 Expr *Arg = 0; 2284 unsigned NumArgs; 2285 2286 QualType ArgType = CanTy; 2287 ExprValueKind VK = VK_LValue; 2288 2289 if (SM == CXXDefaultConstructor) { 2290 Name = Context.DeclarationNames.getCXXConstructorName(CanTy); 2291 NumArgs = 0; 2292 if (RD->needsImplicitDefaultConstructor()) 2293 DeclareImplicitDefaultConstructor(RD); 2294 } else { 2295 if (SM == CXXCopyConstructor || SM == CXXMoveConstructor) { 2296 Name = Context.DeclarationNames.getCXXConstructorName(CanTy); 2297 if (!RD->hasDeclaredCopyConstructor()) 2298 DeclareImplicitCopyConstructor(RD); 2299 if (getLangOpts().CPlusPlus0x && RD->needsImplicitMoveConstructor()) 2300 DeclareImplicitMoveConstructor(RD); 2301 } else { 2302 Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal); 2303 if (!RD->hasDeclaredCopyAssignment()) 2304 DeclareImplicitCopyAssignment(RD); 2305 if (getLangOpts().CPlusPlus0x && RD->needsImplicitMoveAssignment()) 2306 DeclareImplicitMoveAssignment(RD); 2307 } 2308 2309 if (ConstArg) 2310 ArgType.addConst(); 2311 if (VolatileArg) 2312 ArgType.addVolatile(); 2313 2314 // This isn't /really/ specified by the standard, but it's implied 2315 // we should be working from an RValue in the case of move to ensure 2316 // that we prefer to bind to rvalue references, and an LValue in the 2317 // case of copy to ensure we don't bind to rvalue references. 2318 // Possibly an XValue is actually correct in the case of move, but 2319 // there is no semantic difference for class types in this restricted 2320 // case. 2321 if (SM == CXXCopyConstructor || SM == CXXCopyAssignment) 2322 VK = VK_LValue; 2323 else 2324 VK = VK_RValue; 2325 } 2326 2327 OpaqueValueExpr FakeArg(SourceLocation(), ArgType, VK); 2328 2329 if (SM != CXXDefaultConstructor) { 2330 NumArgs = 1; 2331 Arg = &FakeArg; 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 OpaqueValueExpr(SourceLocation(), ThisTy, 2342 RValueThis ? VK_RValue : VK_LValue).Classify(Context); 2343 2344 // Now we perform lookup on the name we computed earlier and do overload 2345 // resolution. Lookup is only performed directly into the class since there 2346 // will always be a (possibly implicit) declaration to shadow any others. 2347 OverloadCandidateSet OCS((SourceLocation())); 2348 DeclContext::lookup_iterator I, E; 2349 2350 llvm::tie(I, E) = RD->lookup(Name); 2351 assert((I != E) && 2352 "lookup for a constructor or assignment operator was empty"); 2353 for ( ; I != E; ++I) { 2354 Decl *Cand = *I; 2355 2356 if (Cand->isInvalidDecl()) 2357 continue; 2358 2359 if (UsingShadowDecl *U = dyn_cast<UsingShadowDecl>(Cand)) { 2360 // FIXME: [namespace.udecl]p15 says that we should only consider a 2361 // using declaration here if it does not match a declaration in the 2362 // derived class. We do not implement this correctly in other cases 2363 // either. 2364 Cand = U->getTargetDecl(); 2365 2366 if (Cand->isInvalidDecl()) 2367 continue; 2368 } 2369 2370 if (CXXMethodDecl *M = dyn_cast<CXXMethodDecl>(Cand)) { 2371 if (SM == CXXCopyAssignment || SM == CXXMoveAssignment) 2372 AddMethodCandidate(M, DeclAccessPair::make(M, AS_public), RD, ThisTy, 2373 Classification, llvm::makeArrayRef(&Arg, NumArgs), 2374 OCS, true); 2375 else 2376 AddOverloadCandidate(M, DeclAccessPair::make(M, AS_public), 2377 llvm::makeArrayRef(&Arg, NumArgs), OCS, true); 2378 } else if (FunctionTemplateDecl *Tmpl = 2379 dyn_cast<FunctionTemplateDecl>(Cand)) { 2380 if (SM == CXXCopyAssignment || SM == CXXMoveAssignment) 2381 AddMethodTemplateCandidate(Tmpl, DeclAccessPair::make(Tmpl, AS_public), 2382 RD, 0, ThisTy, Classification, 2383 llvm::makeArrayRef(&Arg, NumArgs), 2384 OCS, true); 2385 else 2386 AddTemplateOverloadCandidate(Tmpl, DeclAccessPair::make(Tmpl, AS_public), 2387 0, llvm::makeArrayRef(&Arg, NumArgs), 2388 OCS, true); 2389 } else { 2390 assert(isa<UsingDecl>(Cand) && "illegal Kind of operator = Decl"); 2391 } 2392 } 2393 2394 OverloadCandidateSet::iterator Best; 2395 switch (OCS.BestViableFunction(*this, SourceLocation(), Best)) { 2396 case OR_Success: 2397 Result->setMethod(cast<CXXMethodDecl>(Best->Function)); 2398 Result->setKind(SpecialMemberOverloadResult::Success); 2399 break; 2400 2401 case OR_Deleted: 2402 Result->setMethod(cast<CXXMethodDecl>(Best->Function)); 2403 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted); 2404 break; 2405 2406 case OR_Ambiguous: 2407 Result->setMethod(0); 2408 Result->setKind(SpecialMemberOverloadResult::Ambiguous); 2409 break; 2410 2411 case OR_No_Viable_Function: 2412 Result->setMethod(0); 2413 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted); 2414 break; 2415 } 2416 2417 return Result; 2418} 2419 2420/// \brief Look up the default constructor for the given class. 2421CXXConstructorDecl *Sema::LookupDefaultConstructor(CXXRecordDecl *Class) { 2422 SpecialMemberOverloadResult *Result = 2423 LookupSpecialMember(Class, CXXDefaultConstructor, false, false, false, 2424 false, false); 2425 2426 return cast_or_null<CXXConstructorDecl>(Result->getMethod()); 2427} 2428 2429/// \brief Look up the copying constructor for the given class. 2430CXXConstructorDecl *Sema::LookupCopyingConstructor(CXXRecordDecl *Class, 2431 unsigned Quals) { 2432 assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) && 2433 "non-const, non-volatile qualifiers for copy ctor arg"); 2434 SpecialMemberOverloadResult *Result = 2435 LookupSpecialMember(Class, CXXCopyConstructor, Quals & Qualifiers::Const, 2436 Quals & Qualifiers::Volatile, false, false, false); 2437 2438 return cast_or_null<CXXConstructorDecl>(Result->getMethod()); 2439} 2440 2441/// \brief Look up the moving constructor for the given class. 2442CXXConstructorDecl *Sema::LookupMovingConstructor(CXXRecordDecl *Class, 2443 unsigned Quals) { 2444 SpecialMemberOverloadResult *Result = 2445 LookupSpecialMember(Class, CXXMoveConstructor, Quals & Qualifiers::Const, 2446 Quals & Qualifiers::Volatile, false, false, false); 2447 2448 return cast_or_null<CXXConstructorDecl>(Result->getMethod()); 2449} 2450 2451/// \brief Look up the constructors for the given class. 2452DeclContext::lookup_result Sema::LookupConstructors(CXXRecordDecl *Class) { 2453 // If the implicit constructors have not yet been declared, do so now. 2454 if (CanDeclareSpecialMemberFunction(Context, Class)) { 2455 if (Class->needsImplicitDefaultConstructor()) 2456 DeclareImplicitDefaultConstructor(Class); 2457 if (!Class->hasDeclaredCopyConstructor()) 2458 DeclareImplicitCopyConstructor(Class); 2459 if (getLangOpts().CPlusPlus0x && Class->needsImplicitMoveConstructor()) 2460 DeclareImplicitMoveConstructor(Class); 2461 } 2462 2463 CanQualType T = Context.getCanonicalType(Context.getTypeDeclType(Class)); 2464 DeclarationName Name = Context.DeclarationNames.getCXXConstructorName(T); 2465 return Class->lookup(Name); 2466} 2467 2468/// \brief Look up the copying assignment operator for the given class. 2469CXXMethodDecl *Sema::LookupCopyingAssignment(CXXRecordDecl *Class, 2470 unsigned Quals, bool RValueThis, 2471 unsigned ThisQuals) { 2472 assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) && 2473 "non-const, non-volatile qualifiers for copy assignment arg"); 2474 assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) && 2475 "non-const, non-volatile qualifiers for copy assignment this"); 2476 SpecialMemberOverloadResult *Result = 2477 LookupSpecialMember(Class, CXXCopyAssignment, Quals & Qualifiers::Const, 2478 Quals & Qualifiers::Volatile, RValueThis, 2479 ThisQuals & Qualifiers::Const, 2480 ThisQuals & Qualifiers::Volatile); 2481 2482 return Result->getMethod(); 2483} 2484 2485/// \brief Look up the moving assignment operator for the given class. 2486CXXMethodDecl *Sema::LookupMovingAssignment(CXXRecordDecl *Class, 2487 unsigned Quals, 2488 bool RValueThis, 2489 unsigned ThisQuals) { 2490 assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) && 2491 "non-const, non-volatile qualifiers for copy assignment this"); 2492 SpecialMemberOverloadResult *Result = 2493 LookupSpecialMember(Class, CXXMoveAssignment, Quals & Qualifiers::Const, 2494 Quals & Qualifiers::Volatile, RValueThis, 2495 ThisQuals & Qualifiers::Const, 2496 ThisQuals & Qualifiers::Volatile); 2497 2498 return Result->getMethod(); 2499} 2500 2501/// \brief Look for the destructor of the given class. 2502/// 2503/// During semantic analysis, this routine should be used in lieu of 2504/// CXXRecordDecl::getDestructor(). 2505/// 2506/// \returns The destructor for this class. 2507CXXDestructorDecl *Sema::LookupDestructor(CXXRecordDecl *Class) { 2508 return cast<CXXDestructorDecl>(LookupSpecialMember(Class, CXXDestructor, 2509 false, false, false, 2510 false, false)->getMethod()); 2511} 2512 2513/// LookupLiteralOperator - Determine which literal operator should be used for 2514/// a user-defined literal, per C++11 [lex.ext]. 2515/// 2516/// Normal overload resolution is not used to select which literal operator to 2517/// call for a user-defined literal. Look up the provided literal operator name, 2518/// and filter the results to the appropriate set for the given argument types. 2519Sema::LiteralOperatorLookupResult 2520Sema::LookupLiteralOperator(Scope *S, LookupResult &R, 2521 ArrayRef<QualType> ArgTys, 2522 bool AllowRawAndTemplate) { 2523 LookupName(R, S); 2524 assert(R.getResultKind() != LookupResult::Ambiguous && 2525 "literal operator lookup can't be ambiguous"); 2526 2527 // Filter the lookup results appropriately. 2528 LookupResult::Filter F = R.makeFilter(); 2529 2530 bool FoundTemplate = false; 2531 bool FoundRaw = false; 2532 bool FoundExactMatch = false; 2533 2534 while (F.hasNext()) { 2535 Decl *D = F.next(); 2536 if (UsingShadowDecl *USD = dyn_cast<UsingShadowDecl>(D)) 2537 D = USD->getTargetDecl(); 2538 2539 bool IsTemplate = isa<FunctionTemplateDecl>(D); 2540 bool IsRaw = false; 2541 bool IsExactMatch = false; 2542 2543 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 2544 if (FD->getNumParams() == 1 && 2545 FD->getParamDecl(0)->getType()->getAs<PointerType>()) 2546 IsRaw = true; 2547 else { 2548 IsExactMatch = true; 2549 for (unsigned ArgIdx = 0; ArgIdx != ArgTys.size(); ++ArgIdx) { 2550 QualType ParamTy = FD->getParamDecl(ArgIdx)->getType(); 2551 if (!Context.hasSameUnqualifiedType(ArgTys[ArgIdx], ParamTy)) { 2552 IsExactMatch = false; 2553 break; 2554 } 2555 } 2556 } 2557 } 2558 2559 if (IsExactMatch) { 2560 FoundExactMatch = true; 2561 AllowRawAndTemplate = false; 2562 if (FoundRaw || FoundTemplate) { 2563 // Go through again and remove the raw and template decls we've 2564 // already found. 2565 F.restart(); 2566 FoundRaw = FoundTemplate = false; 2567 } 2568 } else if (AllowRawAndTemplate && (IsTemplate || IsRaw)) { 2569 FoundTemplate |= IsTemplate; 2570 FoundRaw |= IsRaw; 2571 } else { 2572 F.erase(); 2573 } 2574 } 2575 2576 F.done(); 2577 2578 // C++11 [lex.ext]p3, p4: If S contains a literal operator with a matching 2579 // parameter type, that is used in preference to a raw literal operator 2580 // or literal operator template. 2581 if (FoundExactMatch) 2582 return LOLR_Cooked; 2583 2584 // C++11 [lex.ext]p3, p4: S shall contain a raw literal operator or a literal 2585 // operator template, but not both. 2586 if (FoundRaw && FoundTemplate) { 2587 Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call) << R.getLookupName(); 2588 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2589 Decl *D = *I; 2590 if (UsingShadowDecl *USD = dyn_cast<UsingShadowDecl>(D)) 2591 D = USD->getTargetDecl(); 2592 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 2593 D = FunTmpl->getTemplatedDecl(); 2594 NoteOverloadCandidate(cast<FunctionDecl>(D)); 2595 } 2596 return LOLR_Error; 2597 } 2598 2599 if (FoundRaw) 2600 return LOLR_Raw; 2601 2602 if (FoundTemplate) 2603 return LOLR_Template; 2604 2605 // Didn't find anything we could use. 2606 Diag(R.getNameLoc(), diag::err_ovl_no_viable_literal_operator) 2607 << R.getLookupName() << (int)ArgTys.size() << ArgTys[0] 2608 << (ArgTys.size() == 2 ? ArgTys[1] : QualType()) << AllowRawAndTemplate; 2609 return LOLR_Error; 2610} 2611 2612void ADLResult::insert(NamedDecl *New) { 2613 NamedDecl *&Old = Decls[cast<NamedDecl>(New->getCanonicalDecl())]; 2614 2615 // If we haven't yet seen a decl for this key, or the last decl 2616 // was exactly this one, we're done. 2617 if (Old == 0 || Old == New) { 2618 Old = New; 2619 return; 2620 } 2621 2622 // Otherwise, decide which is a more recent redeclaration. 2623 FunctionDecl *OldFD, *NewFD; 2624 if (isa<FunctionTemplateDecl>(New)) { 2625 OldFD = cast<FunctionTemplateDecl>(Old)->getTemplatedDecl(); 2626 NewFD = cast<FunctionTemplateDecl>(New)->getTemplatedDecl(); 2627 } else { 2628 OldFD = cast<FunctionDecl>(Old); 2629 NewFD = cast<FunctionDecl>(New); 2630 } 2631 2632 FunctionDecl *Cursor = NewFD; 2633 while (true) { 2634 Cursor = Cursor->getPreviousDecl(); 2635 2636 // If we got to the end without finding OldFD, OldFD is the newer 2637 // declaration; leave things as they are. 2638 if (!Cursor) return; 2639 2640 // If we do find OldFD, then NewFD is newer. 2641 if (Cursor == OldFD) break; 2642 2643 // Otherwise, keep looking. 2644 } 2645 2646 Old = New; 2647} 2648 2649void Sema::ArgumentDependentLookup(DeclarationName Name, bool Operator, 2650 SourceLocation Loc, 2651 llvm::ArrayRef<Expr *> Args, 2652 ADLResult &Result) { 2653 // Find all of the associated namespaces and classes based on the 2654 // arguments we have. 2655 AssociatedNamespaceSet AssociatedNamespaces; 2656 AssociatedClassSet AssociatedClasses; 2657 FindAssociatedClassesAndNamespaces(Loc, Args, 2658 AssociatedNamespaces, 2659 AssociatedClasses); 2660 2661 QualType T1, T2; 2662 if (Operator) { 2663 T1 = Args[0]->getType(); 2664 if (Args.size() >= 2) 2665 T2 = Args[1]->getType(); 2666 } 2667 2668 // C++ [basic.lookup.argdep]p3: 2669 // Let X be the lookup set produced by unqualified lookup (3.4.1) 2670 // and let Y be the lookup set produced by argument dependent 2671 // lookup (defined as follows). If X contains [...] then Y is 2672 // empty. Otherwise Y is the set of declarations found in the 2673 // namespaces associated with the argument types as described 2674 // below. The set of declarations found by the lookup of the name 2675 // is the union of X and Y. 2676 // 2677 // Here, we compute Y and add its members to the overloaded 2678 // candidate set. 2679 for (AssociatedNamespaceSet::iterator NS = AssociatedNamespaces.begin(), 2680 NSEnd = AssociatedNamespaces.end(); 2681 NS != NSEnd; ++NS) { 2682 // When considering an associated namespace, the lookup is the 2683 // same as the lookup performed when the associated namespace is 2684 // used as a qualifier (3.4.3.2) except that: 2685 // 2686 // -- Any using-directives in the associated namespace are 2687 // ignored. 2688 // 2689 // -- Any namespace-scope friend functions declared in 2690 // associated classes are visible within their respective 2691 // namespaces even if they are not visible during an ordinary 2692 // lookup (11.4). 2693 DeclContext::lookup_iterator I, E; 2694 for (llvm::tie(I, E) = (*NS)->lookup(Name); I != E; ++I) { 2695 NamedDecl *D = *I; 2696 // If the only declaration here is an ordinary friend, consider 2697 // it only if it was declared in an associated classes. 2698 if (D->getIdentifierNamespace() == Decl::IDNS_OrdinaryFriend) { 2699 DeclContext *LexDC = D->getLexicalDeclContext(); 2700 if (!AssociatedClasses.count(cast<CXXRecordDecl>(LexDC))) 2701 continue; 2702 } 2703 2704 if (isa<UsingShadowDecl>(D)) 2705 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2706 2707 if (isa<FunctionDecl>(D)) { 2708 if (Operator && 2709 !IsAcceptableNonMemberOperatorCandidate(cast<FunctionDecl>(D), 2710 T1, T2, Context)) 2711 continue; 2712 } else if (!isa<FunctionTemplateDecl>(D)) 2713 continue; 2714 2715 Result.insert(D); 2716 } 2717 } 2718} 2719 2720//---------------------------------------------------------------------------- 2721// Search for all visible declarations. 2722//---------------------------------------------------------------------------- 2723VisibleDeclConsumer::~VisibleDeclConsumer() { } 2724 2725namespace { 2726 2727class ShadowContextRAII; 2728 2729class VisibleDeclsRecord { 2730public: 2731 /// \brief An entry in the shadow map, which is optimized to store a 2732 /// single declaration (the common case) but can also store a list 2733 /// of declarations. 2734 typedef llvm::TinyPtrVector<NamedDecl*> ShadowMapEntry; 2735 2736private: 2737 /// \brief A mapping from declaration names to the declarations that have 2738 /// this name within a particular scope. 2739 typedef llvm::DenseMap<DeclarationName, ShadowMapEntry> ShadowMap; 2740 2741 /// \brief A list of shadow maps, which is used to model name hiding. 2742 std::list<ShadowMap> ShadowMaps; 2743 2744 /// \brief The declaration contexts we have already visited. 2745 llvm::SmallPtrSet<DeclContext *, 8> VisitedContexts; 2746 2747 friend class ShadowContextRAII; 2748 2749public: 2750 /// \brief Determine whether we have already visited this context 2751 /// (and, if not, note that we are going to visit that context now). 2752 bool visitedContext(DeclContext *Ctx) { 2753 return !VisitedContexts.insert(Ctx); 2754 } 2755 2756 bool alreadyVisitedContext(DeclContext *Ctx) { 2757 return VisitedContexts.count(Ctx); 2758 } 2759 2760 /// \brief Determine whether the given declaration is hidden in the 2761 /// current scope. 2762 /// 2763 /// \returns the declaration that hides the given declaration, or 2764 /// NULL if no such declaration exists. 2765 NamedDecl *checkHidden(NamedDecl *ND); 2766 2767 /// \brief Add a declaration to the current shadow map. 2768 void add(NamedDecl *ND) { 2769 ShadowMaps.back()[ND->getDeclName()].push_back(ND); 2770 } 2771}; 2772 2773/// \brief RAII object that records when we've entered a shadow context. 2774class ShadowContextRAII { 2775 VisibleDeclsRecord &Visible; 2776 2777 typedef VisibleDeclsRecord::ShadowMap ShadowMap; 2778 2779public: 2780 ShadowContextRAII(VisibleDeclsRecord &Visible) : Visible(Visible) { 2781 Visible.ShadowMaps.push_back(ShadowMap()); 2782 } 2783 2784 ~ShadowContextRAII() { 2785 Visible.ShadowMaps.pop_back(); 2786 } 2787}; 2788 2789} // end anonymous namespace 2790 2791NamedDecl *VisibleDeclsRecord::checkHidden(NamedDecl *ND) { 2792 // Look through using declarations. 2793 ND = ND->getUnderlyingDecl(); 2794 2795 unsigned IDNS = ND->getIdentifierNamespace(); 2796 std::list<ShadowMap>::reverse_iterator SM = ShadowMaps.rbegin(); 2797 for (std::list<ShadowMap>::reverse_iterator SMEnd = ShadowMaps.rend(); 2798 SM != SMEnd; ++SM) { 2799 ShadowMap::iterator Pos = SM->find(ND->getDeclName()); 2800 if (Pos == SM->end()) 2801 continue; 2802 2803 for (ShadowMapEntry::iterator I = Pos->second.begin(), 2804 IEnd = Pos->second.end(); 2805 I != IEnd; ++I) { 2806 // A tag declaration does not hide a non-tag declaration. 2807 if ((*I)->hasTagIdentifierNamespace() && 2808 (IDNS & (Decl::IDNS_Member | Decl::IDNS_Ordinary | 2809 Decl::IDNS_ObjCProtocol))) 2810 continue; 2811 2812 // Protocols are in distinct namespaces from everything else. 2813 if ((((*I)->getIdentifierNamespace() & Decl::IDNS_ObjCProtocol) 2814 || (IDNS & Decl::IDNS_ObjCProtocol)) && 2815 (*I)->getIdentifierNamespace() != IDNS) 2816 continue; 2817 2818 // Functions and function templates in the same scope overload 2819 // rather than hide. FIXME: Look for hiding based on function 2820 // signatures! 2821 if ((*I)->isFunctionOrFunctionTemplate() && 2822 ND->isFunctionOrFunctionTemplate() && 2823 SM == ShadowMaps.rbegin()) 2824 continue; 2825 2826 // We've found a declaration that hides this one. 2827 return *I; 2828 } 2829 } 2830 2831 return 0; 2832} 2833 2834static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result, 2835 bool QualifiedNameLookup, 2836 bool InBaseClass, 2837 VisibleDeclConsumer &Consumer, 2838 VisibleDeclsRecord &Visited) { 2839 if (!Ctx) 2840 return; 2841 2842 // Make sure we don't visit the same context twice. 2843 if (Visited.visitedContext(Ctx->getPrimaryContext())) 2844 return; 2845 2846 if (CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(Ctx)) 2847 Result.getSema().ForceDeclarationOfImplicitMembers(Class); 2848 2849 // Enumerate all of the results in this context. 2850 for (DeclContext::all_lookups_iterator L = Ctx->lookups_begin(), 2851 LEnd = Ctx->lookups_end(); 2852 L != LEnd; ++L) { 2853 for (DeclContext::lookup_result R = *L; R.first != R.second; ++R.first) { 2854 if (NamedDecl *ND = dyn_cast<NamedDecl>(*R.first)) { 2855 if ((ND = Result.getAcceptableDecl(ND))) { 2856 Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass); 2857 Visited.add(ND); 2858 } 2859 } 2860 } 2861 } 2862 2863 // Traverse using directives for qualified name lookup. 2864 if (QualifiedNameLookup) { 2865 ShadowContextRAII Shadow(Visited); 2866 DeclContext::udir_iterator I, E; 2867 for (llvm::tie(I, E) = Ctx->getUsingDirectives(); I != E; ++I) { 2868 LookupVisibleDecls((*I)->getNominatedNamespace(), Result, 2869 QualifiedNameLookup, InBaseClass, Consumer, Visited); 2870 } 2871 } 2872 2873 // Traverse the contexts of inherited C++ classes. 2874 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) { 2875 if (!Record->hasDefinition()) 2876 return; 2877 2878 for (CXXRecordDecl::base_class_iterator B = Record->bases_begin(), 2879 BEnd = Record->bases_end(); 2880 B != BEnd; ++B) { 2881 QualType BaseType = B->getType(); 2882 2883 // Don't look into dependent bases, because name lookup can't look 2884 // there anyway. 2885 if (BaseType->isDependentType()) 2886 continue; 2887 2888 const RecordType *Record = BaseType->getAs<RecordType>(); 2889 if (!Record) 2890 continue; 2891 2892 // FIXME: It would be nice to be able to determine whether referencing 2893 // a particular member would be ambiguous. For example, given 2894 // 2895 // struct A { int member; }; 2896 // struct B { int member; }; 2897 // struct C : A, B { }; 2898 // 2899 // void f(C *c) { c->### } 2900 // 2901 // accessing 'member' would result in an ambiguity. However, we 2902 // could be smart enough to qualify the member with the base 2903 // class, e.g., 2904 // 2905 // c->B::member 2906 // 2907 // or 2908 // 2909 // c->A::member 2910 2911 // Find results in this base class (and its bases). 2912 ShadowContextRAII Shadow(Visited); 2913 LookupVisibleDecls(Record->getDecl(), Result, QualifiedNameLookup, 2914 true, Consumer, Visited); 2915 } 2916 } 2917 2918 // Traverse the contexts of Objective-C classes. 2919 if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>(Ctx)) { 2920 // Traverse categories. 2921 for (ObjCCategoryDecl *Category = IFace->getCategoryList(); 2922 Category; Category = Category->getNextClassCategory()) { 2923 ShadowContextRAII Shadow(Visited); 2924 LookupVisibleDecls(Category, Result, QualifiedNameLookup, false, 2925 Consumer, Visited); 2926 } 2927 2928 // Traverse protocols. 2929 for (ObjCInterfaceDecl::all_protocol_iterator 2930 I = IFace->all_referenced_protocol_begin(), 2931 E = IFace->all_referenced_protocol_end(); I != E; ++I) { 2932 ShadowContextRAII Shadow(Visited); 2933 LookupVisibleDecls(*I, Result, QualifiedNameLookup, false, Consumer, 2934 Visited); 2935 } 2936 2937 // Traverse the superclass. 2938 if (IFace->getSuperClass()) { 2939 ShadowContextRAII Shadow(Visited); 2940 LookupVisibleDecls(IFace->getSuperClass(), Result, QualifiedNameLookup, 2941 true, Consumer, Visited); 2942 } 2943 2944 // If there is an implementation, traverse it. We do this to find 2945 // synthesized ivars. 2946 if (IFace->getImplementation()) { 2947 ShadowContextRAII Shadow(Visited); 2948 LookupVisibleDecls(IFace->getImplementation(), Result, 2949 QualifiedNameLookup, InBaseClass, Consumer, Visited); 2950 } 2951 } else if (ObjCProtocolDecl *Protocol = dyn_cast<ObjCProtocolDecl>(Ctx)) { 2952 for (ObjCProtocolDecl::protocol_iterator I = Protocol->protocol_begin(), 2953 E = Protocol->protocol_end(); I != E; ++I) { 2954 ShadowContextRAII Shadow(Visited); 2955 LookupVisibleDecls(*I, Result, QualifiedNameLookup, false, Consumer, 2956 Visited); 2957 } 2958 } else if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(Ctx)) { 2959 for (ObjCCategoryDecl::protocol_iterator I = Category->protocol_begin(), 2960 E = Category->protocol_end(); I != E; ++I) { 2961 ShadowContextRAII Shadow(Visited); 2962 LookupVisibleDecls(*I, Result, QualifiedNameLookup, false, Consumer, 2963 Visited); 2964 } 2965 2966 // If there is an implementation, traverse it. 2967 if (Category->getImplementation()) { 2968 ShadowContextRAII Shadow(Visited); 2969 LookupVisibleDecls(Category->getImplementation(), Result, 2970 QualifiedNameLookup, true, Consumer, Visited); 2971 } 2972 } 2973} 2974 2975static void LookupVisibleDecls(Scope *S, LookupResult &Result, 2976 UnqualUsingDirectiveSet &UDirs, 2977 VisibleDeclConsumer &Consumer, 2978 VisibleDeclsRecord &Visited) { 2979 if (!S) 2980 return; 2981 2982 if (!S->getEntity() || 2983 (!S->getParent() && 2984 !Visited.alreadyVisitedContext((DeclContext *)S->getEntity())) || 2985 ((DeclContext *)S->getEntity())->isFunctionOrMethod()) { 2986 // Walk through the declarations in this Scope. 2987 for (Scope::decl_iterator D = S->decl_begin(), DEnd = S->decl_end(); 2988 D != DEnd; ++D) { 2989 if (NamedDecl *ND = dyn_cast<NamedDecl>(*D)) 2990 if ((ND = Result.getAcceptableDecl(ND))) { 2991 Consumer.FoundDecl(ND, Visited.checkHidden(ND), 0, false); 2992 Visited.add(ND); 2993 } 2994 } 2995 } 2996 2997 // FIXME: C++ [temp.local]p8 2998 DeclContext *Entity = 0; 2999 if (S->getEntity()) { 3000 // Look into this scope's declaration context, along with any of its 3001 // parent lookup contexts (e.g., enclosing classes), up to the point 3002 // where we hit the context stored in the next outer scope. 3003 Entity = (DeclContext *)S->getEntity(); 3004 DeclContext *OuterCtx = findOuterContext(S).first; // FIXME 3005 3006 for (DeclContext *Ctx = Entity; Ctx && !Ctx->Equals(OuterCtx); 3007 Ctx = Ctx->getLookupParent()) { 3008 if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) { 3009 if (Method->isInstanceMethod()) { 3010 // For instance methods, look for ivars in the method's interface. 3011 LookupResult IvarResult(Result.getSema(), Result.getLookupName(), 3012 Result.getNameLoc(), Sema::LookupMemberName); 3013 if (ObjCInterfaceDecl *IFace = Method->getClassInterface()) { 3014 LookupVisibleDecls(IFace, IvarResult, /*QualifiedNameLookup=*/false, 3015 /*InBaseClass=*/false, Consumer, Visited); 3016 } 3017 } 3018 3019 // We've already performed all of the name lookup that we need 3020 // to for Objective-C methods; the next context will be the 3021 // outer scope. 3022 break; 3023 } 3024 3025 if (Ctx->isFunctionOrMethod()) 3026 continue; 3027 3028 LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/false, 3029 /*InBaseClass=*/false, Consumer, Visited); 3030 } 3031 } else if (!S->getParent()) { 3032 // Look into the translation unit scope. We walk through the translation 3033 // unit's declaration context, because the Scope itself won't have all of 3034 // the declarations if we loaded a precompiled header. 3035 // FIXME: We would like the translation unit's Scope object to point to the 3036 // translation unit, so we don't need this special "if" branch. However, 3037 // doing so would force the normal C++ name-lookup code to look into the 3038 // translation unit decl when the IdentifierInfo chains would suffice. 3039 // Once we fix that problem (which is part of a more general "don't look 3040 // in DeclContexts unless we have to" optimization), we can eliminate this. 3041 Entity = Result.getSema().Context.getTranslationUnitDecl(); 3042 LookupVisibleDecls(Entity, Result, /*QualifiedNameLookup=*/false, 3043 /*InBaseClass=*/false, Consumer, Visited); 3044 } 3045 3046 if (Entity) { 3047 // Lookup visible declarations in any namespaces found by using 3048 // directives. 3049 UnqualUsingDirectiveSet::const_iterator UI, UEnd; 3050 llvm::tie(UI, UEnd) = UDirs.getNamespacesFor(Entity); 3051 for (; UI != UEnd; ++UI) 3052 LookupVisibleDecls(const_cast<DeclContext *>(UI->getNominatedNamespace()), 3053 Result, /*QualifiedNameLookup=*/false, 3054 /*InBaseClass=*/false, Consumer, Visited); 3055 } 3056 3057 // Lookup names in the parent scope. 3058 ShadowContextRAII Shadow(Visited); 3059 LookupVisibleDecls(S->getParent(), Result, UDirs, Consumer, Visited); 3060} 3061 3062void Sema::LookupVisibleDecls(Scope *S, LookupNameKind Kind, 3063 VisibleDeclConsumer &Consumer, 3064 bool IncludeGlobalScope) { 3065 // Determine the set of using directives available during 3066 // unqualified name lookup. 3067 Scope *Initial = S; 3068 UnqualUsingDirectiveSet UDirs; 3069 if (getLangOpts().CPlusPlus) { 3070 // Find the first namespace or translation-unit scope. 3071 while (S && !isNamespaceOrTranslationUnitScope(S)) 3072 S = S->getParent(); 3073 3074 UDirs.visitScopeChain(Initial, S); 3075 } 3076 UDirs.done(); 3077 3078 // Look for visible declarations. 3079 LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind); 3080 VisibleDeclsRecord Visited; 3081 if (!IncludeGlobalScope) 3082 Visited.visitedContext(Context.getTranslationUnitDecl()); 3083 ShadowContextRAII Shadow(Visited); 3084 ::LookupVisibleDecls(Initial, Result, UDirs, Consumer, Visited); 3085} 3086 3087void Sema::LookupVisibleDecls(DeclContext *Ctx, LookupNameKind Kind, 3088 VisibleDeclConsumer &Consumer, 3089 bool IncludeGlobalScope) { 3090 LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind); 3091 VisibleDeclsRecord Visited; 3092 if (!IncludeGlobalScope) 3093 Visited.visitedContext(Context.getTranslationUnitDecl()); 3094 ShadowContextRAII Shadow(Visited); 3095 ::LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/true, 3096 /*InBaseClass=*/false, Consumer, Visited); 3097} 3098 3099/// LookupOrCreateLabel - Do a name lookup of a label with the specified name. 3100/// If GnuLabelLoc is a valid source location, then this is a definition 3101/// of an __label__ label name, otherwise it is a normal label definition 3102/// or use. 3103LabelDecl *Sema::LookupOrCreateLabel(IdentifierInfo *II, SourceLocation Loc, 3104 SourceLocation GnuLabelLoc) { 3105 // Do a lookup to see if we have a label with this name already. 3106 NamedDecl *Res = 0; 3107 3108 if (GnuLabelLoc.isValid()) { 3109 // Local label definitions always shadow existing labels. 3110 Res = LabelDecl::Create(Context, CurContext, Loc, II, GnuLabelLoc); 3111 Scope *S = CurScope; 3112 PushOnScopeChains(Res, S, true); 3113 return cast<LabelDecl>(Res); 3114 } 3115 3116 // Not a GNU local label. 3117 Res = LookupSingleName(CurScope, II, Loc, LookupLabel, NotForRedeclaration); 3118 // If we found a label, check to see if it is in the same context as us. 3119 // When in a Block, we don't want to reuse a label in an enclosing function. 3120 if (Res && Res->getDeclContext() != CurContext) 3121 Res = 0; 3122 if (Res == 0) { 3123 // If not forward referenced or defined already, create the backing decl. 3124 Res = LabelDecl::Create(Context, CurContext, Loc, II); 3125 Scope *S = CurScope->getFnParent(); 3126 assert(S && "Not in a function?"); 3127 PushOnScopeChains(Res, S, true); 3128 } 3129 return cast<LabelDecl>(Res); 3130} 3131 3132//===----------------------------------------------------------------------===// 3133// Typo correction 3134//===----------------------------------------------------------------------===// 3135 3136namespace { 3137 3138typedef llvm::SmallVector<TypoCorrection, 1> TypoResultList; 3139typedef llvm::StringMap<TypoResultList, llvm::BumpPtrAllocator> TypoResultsMap; 3140typedef std::map<unsigned, TypoResultsMap> TypoEditDistanceMap; 3141 3142static const unsigned MaxTypoDistanceResultSets = 5; 3143 3144class TypoCorrectionConsumer : public VisibleDeclConsumer { 3145 /// \brief The name written that is a typo in the source. 3146 StringRef Typo; 3147 3148 /// \brief The results found that have the smallest edit distance 3149 /// found (so far) with the typo name. 3150 /// 3151 /// The pointer value being set to the current DeclContext indicates 3152 /// whether there is a keyword with this name. 3153 TypoEditDistanceMap CorrectionResults; 3154 3155 Sema &SemaRef; 3156 3157public: 3158 explicit TypoCorrectionConsumer(Sema &SemaRef, IdentifierInfo *Typo) 3159 : Typo(Typo->getName()), 3160 SemaRef(SemaRef) { } 3161 3162 virtual void FoundDecl(NamedDecl *ND, NamedDecl *Hiding, DeclContext *Ctx, 3163 bool InBaseClass); 3164 void FoundName(StringRef Name); 3165 void addKeywordResult(StringRef Keyword); 3166 void addName(StringRef Name, NamedDecl *ND, unsigned Distance, 3167 NestedNameSpecifier *NNS=NULL, bool isKeyword=false); 3168 void addCorrection(TypoCorrection Correction); 3169 3170 typedef TypoResultsMap::iterator result_iterator; 3171 typedef TypoEditDistanceMap::iterator distance_iterator; 3172 distance_iterator begin() { return CorrectionResults.begin(); } 3173 distance_iterator end() { return CorrectionResults.end(); } 3174 void erase(distance_iterator I) { CorrectionResults.erase(I); } 3175 unsigned size() const { return CorrectionResults.size(); } 3176 bool empty() const { return CorrectionResults.empty(); } 3177 3178 TypoResultList &operator[](StringRef Name) { 3179 return CorrectionResults.begin()->second[Name]; 3180 } 3181 3182 unsigned getBestEditDistance(bool Normalized) { 3183 if (CorrectionResults.empty()) 3184 return (std::numeric_limits<unsigned>::max)(); 3185 3186 unsigned BestED = CorrectionResults.begin()->first; 3187 return Normalized ? TypoCorrection::NormalizeEditDistance(BestED) : BestED; 3188 } 3189 3190 TypoResultsMap &getBestResults() { 3191 return CorrectionResults.begin()->second; 3192 } 3193 3194}; 3195 3196} 3197 3198void TypoCorrectionConsumer::FoundDecl(NamedDecl *ND, NamedDecl *Hiding, 3199 DeclContext *Ctx, bool InBaseClass) { 3200 // Don't consider hidden names for typo correction. 3201 if (Hiding) 3202 return; 3203 3204 // Only consider entities with identifiers for names, ignoring 3205 // special names (constructors, overloaded operators, selectors, 3206 // etc.). 3207 IdentifierInfo *Name = ND->getIdentifier(); 3208 if (!Name) 3209 return; 3210 3211 FoundName(Name->getName()); 3212} 3213 3214void TypoCorrectionConsumer::FoundName(StringRef Name) { 3215 // Use a simple length-based heuristic to determine the minimum possible 3216 // edit distance. If the minimum isn't good enough, bail out early. 3217 unsigned MinED = abs((int)Name.size() - (int)Typo.size()); 3218 if (MinED && Typo.size() / MinED < 3) 3219 return; 3220 3221 // Compute an upper bound on the allowable edit distance, so that the 3222 // edit-distance algorithm can short-circuit. 3223 unsigned UpperBound = (Typo.size() + 2) / 3; 3224 3225 // Compute the edit distance between the typo and the name of this 3226 // entity, and add the identifier to the list of results. 3227 addName(Name, NULL, Typo.edit_distance(Name, true, UpperBound)); 3228} 3229 3230void TypoCorrectionConsumer::addKeywordResult(StringRef Keyword) { 3231 // Compute the edit distance between the typo and this keyword, 3232 // and add the keyword to the list of results. 3233 addName(Keyword, NULL, Typo.edit_distance(Keyword), NULL, true); 3234} 3235 3236void TypoCorrectionConsumer::addName(StringRef Name, 3237 NamedDecl *ND, 3238 unsigned Distance, 3239 NestedNameSpecifier *NNS, 3240 bool isKeyword) { 3241 TypoCorrection TC(&SemaRef.Context.Idents.get(Name), ND, NNS, Distance); 3242 if (isKeyword) TC.makeKeyword(); 3243 addCorrection(TC); 3244} 3245 3246void TypoCorrectionConsumer::addCorrection(TypoCorrection Correction) { 3247 StringRef Name = Correction.getCorrectionAsIdentifierInfo()->getName(); 3248 TypoResultList &CList = 3249 CorrectionResults[Correction.getEditDistance(false)][Name]; 3250 3251 if (!CList.empty() && !CList.back().isResolved()) 3252 CList.pop_back(); 3253 if (NamedDecl *NewND = Correction.getCorrectionDecl()) { 3254 std::string CorrectionStr = Correction.getAsString(SemaRef.getLangOpts()); 3255 for (TypoResultList::iterator RI = CList.begin(), RIEnd = CList.end(); 3256 RI != RIEnd; ++RI) { 3257 // If the Correction refers to a decl already in the result list, 3258 // replace the existing result if the string representation of Correction 3259 // comes before the current result alphabetically, then stop as there is 3260 // nothing more to be done to add Correction to the candidate set. 3261 if (RI->getCorrectionDecl() == NewND) { 3262 if (CorrectionStr < RI->getAsString(SemaRef.getLangOpts())) 3263 *RI = Correction; 3264 return; 3265 } 3266 } 3267 } 3268 if (CList.empty() || Correction.isResolved()) 3269 CList.push_back(Correction); 3270 3271 while (CorrectionResults.size() > MaxTypoDistanceResultSets) 3272 erase(llvm::prior(CorrectionResults.end())); 3273} 3274 3275// Fill the supplied vector with the IdentifierInfo pointers for each piece of 3276// the given NestedNameSpecifier (i.e. given a NestedNameSpecifier "foo::bar::", 3277// fill the vector with the IdentifierInfo pointers for "foo" and "bar"). 3278static void getNestedNameSpecifierIdentifiers( 3279 NestedNameSpecifier *NNS, 3280 SmallVectorImpl<const IdentifierInfo*> &Identifiers) { 3281 if (NestedNameSpecifier *Prefix = NNS->getPrefix()) 3282 getNestedNameSpecifierIdentifiers(Prefix, Identifiers); 3283 else 3284 Identifiers.clear(); 3285 3286 const IdentifierInfo *II = NULL; 3287 3288 switch (NNS->getKind()) { 3289 case NestedNameSpecifier::Identifier: 3290 II = NNS->getAsIdentifier(); 3291 break; 3292 3293 case NestedNameSpecifier::Namespace: 3294 if (NNS->getAsNamespace()->isAnonymousNamespace()) 3295 return; 3296 II = NNS->getAsNamespace()->getIdentifier(); 3297 break; 3298 3299 case NestedNameSpecifier::NamespaceAlias: 3300 II = NNS->getAsNamespaceAlias()->getIdentifier(); 3301 break; 3302 3303 case NestedNameSpecifier::TypeSpecWithTemplate: 3304 case NestedNameSpecifier::TypeSpec: 3305 II = QualType(NNS->getAsType(), 0).getBaseTypeIdentifier(); 3306 break; 3307 3308 case NestedNameSpecifier::Global: 3309 return; 3310 } 3311 3312 if (II) 3313 Identifiers.push_back(II); 3314} 3315 3316namespace { 3317 3318class SpecifierInfo { 3319 public: 3320 DeclContext* DeclCtx; 3321 NestedNameSpecifier* NameSpecifier; 3322 unsigned EditDistance; 3323 3324 SpecifierInfo(DeclContext *Ctx, NestedNameSpecifier *NNS, unsigned ED) 3325 : DeclCtx(Ctx), NameSpecifier(NNS), EditDistance(ED) {} 3326}; 3327 3328typedef SmallVector<DeclContext*, 4> DeclContextList; 3329typedef SmallVector<SpecifierInfo, 16> SpecifierInfoList; 3330 3331class NamespaceSpecifierSet { 3332 ASTContext &Context; 3333 DeclContextList CurContextChain; 3334 SmallVector<const IdentifierInfo*, 4> CurContextIdentifiers; 3335 SmallVector<const IdentifierInfo*, 4> CurNameSpecifierIdentifiers; 3336 bool isSorted; 3337 3338 SpecifierInfoList Specifiers; 3339 llvm::SmallSetVector<unsigned, 4> Distances; 3340 llvm::DenseMap<unsigned, SpecifierInfoList> DistanceMap; 3341 3342 /// \brief Helper for building the list of DeclContexts between the current 3343 /// context and the top of the translation unit 3344 static DeclContextList BuildContextChain(DeclContext *Start); 3345 3346 void SortNamespaces(); 3347 3348 public: 3349 NamespaceSpecifierSet(ASTContext &Context, DeclContext *CurContext, 3350 CXXScopeSpec *CurScopeSpec) 3351 : Context(Context), CurContextChain(BuildContextChain(CurContext)), 3352 isSorted(true) { 3353 if (CurScopeSpec && CurScopeSpec->getScopeRep()) 3354 getNestedNameSpecifierIdentifiers(CurScopeSpec->getScopeRep(), 3355 CurNameSpecifierIdentifiers); 3356 // Build the list of identifiers that would be used for an absolute 3357 // (from the global context) NestedNameSpecifier referring to the current 3358 // context. 3359 for (DeclContextList::reverse_iterator C = CurContextChain.rbegin(), 3360 CEnd = CurContextChain.rend(); 3361 C != CEnd; ++C) { 3362 if (NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(*C)) 3363 CurContextIdentifiers.push_back(ND->getIdentifier()); 3364 } 3365 } 3366 3367 /// \brief Add the namespace to the set, computing the corresponding 3368 /// NestedNameSpecifier and its distance in the process. 3369 void AddNamespace(NamespaceDecl *ND); 3370 3371 typedef SpecifierInfoList::iterator iterator; 3372 iterator begin() { 3373 if (!isSorted) SortNamespaces(); 3374 return Specifiers.begin(); 3375 } 3376 iterator end() { return Specifiers.end(); } 3377}; 3378 3379} 3380 3381DeclContextList NamespaceSpecifierSet::BuildContextChain(DeclContext *Start) { 3382 assert(Start && "Bulding a context chain from a null context"); 3383 DeclContextList Chain; 3384 for (DeclContext *DC = Start->getPrimaryContext(); DC != NULL; 3385 DC = DC->getLookupParent()) { 3386 NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(DC); 3387 if (!DC->isInlineNamespace() && !DC->isTransparentContext() && 3388 !(ND && ND->isAnonymousNamespace())) 3389 Chain.push_back(DC->getPrimaryContext()); 3390 } 3391 return Chain; 3392} 3393 3394void NamespaceSpecifierSet::SortNamespaces() { 3395 SmallVector<unsigned, 4> sortedDistances; 3396 sortedDistances.append(Distances.begin(), Distances.end()); 3397 3398 if (sortedDistances.size() > 1) 3399 std::sort(sortedDistances.begin(), sortedDistances.end()); 3400 3401 Specifiers.clear(); 3402 for (SmallVector<unsigned, 4>::iterator DI = sortedDistances.begin(), 3403 DIEnd = sortedDistances.end(); 3404 DI != DIEnd; ++DI) { 3405 SpecifierInfoList &SpecList = DistanceMap[*DI]; 3406 Specifiers.append(SpecList.begin(), SpecList.end()); 3407 } 3408 3409 isSorted = true; 3410} 3411 3412void NamespaceSpecifierSet::AddNamespace(NamespaceDecl *ND) { 3413 DeclContext *Ctx = cast<DeclContext>(ND); 3414 NestedNameSpecifier *NNS = NULL; 3415 unsigned NumSpecifiers = 0; 3416 DeclContextList NamespaceDeclChain(BuildContextChain(Ctx)); 3417 DeclContextList FullNamespaceDeclChain(NamespaceDeclChain); 3418 3419 // Eliminate common elements from the two DeclContext chains. 3420 for (DeclContextList::reverse_iterator C = CurContextChain.rbegin(), 3421 CEnd = CurContextChain.rend(); 3422 C != CEnd && !NamespaceDeclChain.empty() && 3423 NamespaceDeclChain.back() == *C; ++C) { 3424 NamespaceDeclChain.pop_back(); 3425 } 3426 3427 // Add an explicit leading '::' specifier if needed. 3428 if (NamespaceDecl *ND = 3429 NamespaceDeclChain.empty() ? NULL : 3430 dyn_cast_or_null<NamespaceDecl>(NamespaceDeclChain.back())) { 3431 IdentifierInfo *Name = ND->getIdentifier(); 3432 if (std::find(CurContextIdentifiers.begin(), CurContextIdentifiers.end(), 3433 Name) != CurContextIdentifiers.end() || 3434 std::find(CurNameSpecifierIdentifiers.begin(), 3435 CurNameSpecifierIdentifiers.end(), 3436 Name) != CurNameSpecifierIdentifiers.end()) { 3437 NamespaceDeclChain = FullNamespaceDeclChain; 3438 NNS = NestedNameSpecifier::GlobalSpecifier(Context); 3439 } 3440 } 3441 3442 // Build the NestedNameSpecifier from what is left of the NamespaceDeclChain 3443 for (DeclContextList::reverse_iterator C = NamespaceDeclChain.rbegin(), 3444 CEnd = NamespaceDeclChain.rend(); 3445 C != CEnd; ++C) { 3446 NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(*C); 3447 if (ND) { 3448 NNS = NestedNameSpecifier::Create(Context, NNS, ND); 3449 ++NumSpecifiers; 3450 } 3451 } 3452 3453 // If the built NestedNameSpecifier would be replacing an existing 3454 // NestedNameSpecifier, use the number of component identifiers that 3455 // would need to be changed as the edit distance instead of the number 3456 // of components in the built NestedNameSpecifier. 3457 if (NNS && !CurNameSpecifierIdentifiers.empty()) { 3458 SmallVector<const IdentifierInfo*, 4> NewNameSpecifierIdentifiers; 3459 getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers); 3460 NumSpecifiers = llvm::ComputeEditDistance( 3461 llvm::ArrayRef<const IdentifierInfo*>(CurNameSpecifierIdentifiers), 3462 llvm::ArrayRef<const IdentifierInfo*>(NewNameSpecifierIdentifiers)); 3463 } 3464 3465 isSorted = false; 3466 Distances.insert(NumSpecifiers); 3467 DistanceMap[NumSpecifiers].push_back(SpecifierInfo(Ctx, NNS, NumSpecifiers)); 3468} 3469 3470/// \brief Perform name lookup for a possible result for typo correction. 3471static void LookupPotentialTypoResult(Sema &SemaRef, 3472 LookupResult &Res, 3473 IdentifierInfo *Name, 3474 Scope *S, CXXScopeSpec *SS, 3475 DeclContext *MemberContext, 3476 bool EnteringContext, 3477 bool isObjCIvarLookup) { 3478 Res.suppressDiagnostics(); 3479 Res.clear(); 3480 Res.setLookupName(Name); 3481 if (MemberContext) { 3482 if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(MemberContext)) { 3483 if (isObjCIvarLookup) { 3484 if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(Name)) { 3485 Res.addDecl(Ivar); 3486 Res.resolveKind(); 3487 return; 3488 } 3489 } 3490 3491 if (ObjCPropertyDecl *Prop = Class->FindPropertyDeclaration(Name)) { 3492 Res.addDecl(Prop); 3493 Res.resolveKind(); 3494 return; 3495 } 3496 } 3497 3498 SemaRef.LookupQualifiedName(Res, MemberContext); 3499 return; 3500 } 3501 3502 SemaRef.LookupParsedName(Res, S, SS, /*AllowBuiltinCreation=*/false, 3503 EnteringContext); 3504 3505 // Fake ivar lookup; this should really be part of 3506 // LookupParsedName. 3507 if (ObjCMethodDecl *Method = SemaRef.getCurMethodDecl()) { 3508 if (Method->isInstanceMethod() && Method->getClassInterface() && 3509 (Res.empty() || 3510 (Res.isSingleResult() && 3511 Res.getFoundDecl()->isDefinedOutsideFunctionOrMethod()))) { 3512 if (ObjCIvarDecl *IV 3513 = Method->getClassInterface()->lookupInstanceVariable(Name)) { 3514 Res.addDecl(IV); 3515 Res.resolveKind(); 3516 } 3517 } 3518 } 3519} 3520 3521/// \brief Add keywords to the consumer as possible typo corrections. 3522static void AddKeywordsToConsumer(Sema &SemaRef, 3523 TypoCorrectionConsumer &Consumer, 3524 Scope *S, CorrectionCandidateCallback &CCC, 3525 bool AfterNestedNameSpecifier) { 3526 if (AfterNestedNameSpecifier) { 3527 // For 'X::', we know exactly which keywords can appear next. 3528 Consumer.addKeywordResult("template"); 3529 if (CCC.WantExpressionKeywords) 3530 Consumer.addKeywordResult("operator"); 3531 return; 3532 } 3533 3534 if (CCC.WantObjCSuper) 3535 Consumer.addKeywordResult("super"); 3536 3537 if (CCC.WantTypeSpecifiers) { 3538 // Add type-specifier keywords to the set of results. 3539 const char *CTypeSpecs[] = { 3540 "char", "const", "double", "enum", "float", "int", "long", "short", 3541 "signed", "struct", "union", "unsigned", "void", "volatile", 3542 "_Complex", "_Imaginary", 3543 // storage-specifiers as well 3544 "extern", "inline", "static", "typedef" 3545 }; 3546 3547 const unsigned NumCTypeSpecs = sizeof(CTypeSpecs) / sizeof(CTypeSpecs[0]); 3548 for (unsigned I = 0; I != NumCTypeSpecs; ++I) 3549 Consumer.addKeywordResult(CTypeSpecs[I]); 3550 3551 if (SemaRef.getLangOpts().C99) 3552 Consumer.addKeywordResult("restrict"); 3553 if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus) 3554 Consumer.addKeywordResult("bool"); 3555 else if (SemaRef.getLangOpts().C99) 3556 Consumer.addKeywordResult("_Bool"); 3557 3558 if (SemaRef.getLangOpts().CPlusPlus) { 3559 Consumer.addKeywordResult("class"); 3560 Consumer.addKeywordResult("typename"); 3561 Consumer.addKeywordResult("wchar_t"); 3562 3563 if (SemaRef.getLangOpts().CPlusPlus0x) { 3564 Consumer.addKeywordResult("char16_t"); 3565 Consumer.addKeywordResult("char32_t"); 3566 Consumer.addKeywordResult("constexpr"); 3567 Consumer.addKeywordResult("decltype"); 3568 Consumer.addKeywordResult("thread_local"); 3569 } 3570 } 3571 3572 if (SemaRef.getLangOpts().GNUMode) 3573 Consumer.addKeywordResult("typeof"); 3574 } 3575 3576 if (CCC.WantCXXNamedCasts && SemaRef.getLangOpts().CPlusPlus) { 3577 Consumer.addKeywordResult("const_cast"); 3578 Consumer.addKeywordResult("dynamic_cast"); 3579 Consumer.addKeywordResult("reinterpret_cast"); 3580 Consumer.addKeywordResult("static_cast"); 3581 } 3582 3583 if (CCC.WantExpressionKeywords) { 3584 Consumer.addKeywordResult("sizeof"); 3585 if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus) { 3586 Consumer.addKeywordResult("false"); 3587 Consumer.addKeywordResult("true"); 3588 } 3589 3590 if (SemaRef.getLangOpts().CPlusPlus) { 3591 const char *CXXExprs[] = { 3592 "delete", "new", "operator", "throw", "typeid" 3593 }; 3594 const unsigned NumCXXExprs = sizeof(CXXExprs) / sizeof(CXXExprs[0]); 3595 for (unsigned I = 0; I != NumCXXExprs; ++I) 3596 Consumer.addKeywordResult(CXXExprs[I]); 3597 3598 if (isa<CXXMethodDecl>(SemaRef.CurContext) && 3599 cast<CXXMethodDecl>(SemaRef.CurContext)->isInstance()) 3600 Consumer.addKeywordResult("this"); 3601 3602 if (SemaRef.getLangOpts().CPlusPlus0x) { 3603 Consumer.addKeywordResult("alignof"); 3604 Consumer.addKeywordResult("nullptr"); 3605 } 3606 } 3607 3608 if (SemaRef.getLangOpts().C11) { 3609 // FIXME: We should not suggest _Alignof if the alignof macro 3610 // is present. 3611 Consumer.addKeywordResult("_Alignof"); 3612 } 3613 } 3614 3615 if (CCC.WantRemainingKeywords) { 3616 if (SemaRef.getCurFunctionOrMethodDecl() || SemaRef.getCurBlock()) { 3617 // Statements. 3618 const char *CStmts[] = { 3619 "do", "else", "for", "goto", "if", "return", "switch", "while" }; 3620 const unsigned NumCStmts = sizeof(CStmts) / sizeof(CStmts[0]); 3621 for (unsigned I = 0; I != NumCStmts; ++I) 3622 Consumer.addKeywordResult(CStmts[I]); 3623 3624 if (SemaRef.getLangOpts().CPlusPlus) { 3625 Consumer.addKeywordResult("catch"); 3626 Consumer.addKeywordResult("try"); 3627 } 3628 3629 if (S && S->getBreakParent()) 3630 Consumer.addKeywordResult("break"); 3631 3632 if (S && S->getContinueParent()) 3633 Consumer.addKeywordResult("continue"); 3634 3635 if (!SemaRef.getCurFunction()->SwitchStack.empty()) { 3636 Consumer.addKeywordResult("case"); 3637 Consumer.addKeywordResult("default"); 3638 } 3639 } else { 3640 if (SemaRef.getLangOpts().CPlusPlus) { 3641 Consumer.addKeywordResult("namespace"); 3642 Consumer.addKeywordResult("template"); 3643 } 3644 3645 if (S && S->isClassScope()) { 3646 Consumer.addKeywordResult("explicit"); 3647 Consumer.addKeywordResult("friend"); 3648 Consumer.addKeywordResult("mutable"); 3649 Consumer.addKeywordResult("private"); 3650 Consumer.addKeywordResult("protected"); 3651 Consumer.addKeywordResult("public"); 3652 Consumer.addKeywordResult("virtual"); 3653 } 3654 } 3655 3656 if (SemaRef.getLangOpts().CPlusPlus) { 3657 Consumer.addKeywordResult("using"); 3658 3659 if (SemaRef.getLangOpts().CPlusPlus0x) 3660 Consumer.addKeywordResult("static_assert"); 3661 } 3662 } 3663} 3664 3665static bool isCandidateViable(CorrectionCandidateCallback &CCC, 3666 TypoCorrection &Candidate) { 3667 Candidate.setCallbackDistance(CCC.RankCandidate(Candidate)); 3668 return Candidate.getEditDistance(false) != TypoCorrection::InvalidDistance; 3669} 3670 3671/// \brief Try to "correct" a typo in the source code by finding 3672/// visible declarations whose names are similar to the name that was 3673/// present in the source code. 3674/// 3675/// \param TypoName the \c DeclarationNameInfo structure that contains 3676/// the name that was present in the source code along with its location. 3677/// 3678/// \param LookupKind the name-lookup criteria used to search for the name. 3679/// 3680/// \param S the scope in which name lookup occurs. 3681/// 3682/// \param SS the nested-name-specifier that precedes the name we're 3683/// looking for, if present. 3684/// 3685/// \param CCC A CorrectionCandidateCallback object that provides further 3686/// validation of typo correction candidates. It also provides flags for 3687/// determining the set of keywords permitted. 3688/// 3689/// \param MemberContext if non-NULL, the context in which to look for 3690/// a member access expression. 3691/// 3692/// \param EnteringContext whether we're entering the context described by 3693/// the nested-name-specifier SS. 3694/// 3695/// \param OPT when non-NULL, the search for visible declarations will 3696/// also walk the protocols in the qualified interfaces of \p OPT. 3697/// 3698/// \returns a \c TypoCorrection containing the corrected name if the typo 3699/// along with information such as the \c NamedDecl where the corrected name 3700/// was declared, and any additional \c NestedNameSpecifier needed to access 3701/// it (C++ only). The \c TypoCorrection is empty if there is no correction. 3702TypoCorrection Sema::CorrectTypo(const DeclarationNameInfo &TypoName, 3703 Sema::LookupNameKind LookupKind, 3704 Scope *S, CXXScopeSpec *SS, 3705 CorrectionCandidateCallback &CCC, 3706 DeclContext *MemberContext, 3707 bool EnteringContext, 3708 const ObjCObjectPointerType *OPT) { 3709 if (Diags.hasFatalErrorOccurred() || !getLangOpts().SpellChecking) 3710 return TypoCorrection(); 3711 3712 // In Microsoft mode, don't perform typo correction in a template member 3713 // function dependent context because it interferes with the "lookup into 3714 // dependent bases of class templates" feature. 3715 if (getLangOpts().MicrosoftMode && CurContext->isDependentContext() && 3716 isa<CXXMethodDecl>(CurContext)) 3717 return TypoCorrection(); 3718 3719 // We only attempt to correct typos for identifiers. 3720 IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo(); 3721 if (!Typo) 3722 return TypoCorrection(); 3723 3724 // If the scope specifier itself was invalid, don't try to correct 3725 // typos. 3726 if (SS && SS->isInvalid()) 3727 return TypoCorrection(); 3728 3729 // Never try to correct typos during template deduction or 3730 // instantiation. 3731 if (!ActiveTemplateInstantiations.empty()) 3732 return TypoCorrection(); 3733 3734 NamespaceSpecifierSet Namespaces(Context, CurContext, SS); 3735 3736 TypoCorrectionConsumer Consumer(*this, Typo); 3737 3738 // If a callback object considers an empty typo correction candidate to be 3739 // viable, assume it does not do any actual validation of the candidates. 3740 TypoCorrection EmptyCorrection; 3741 bool ValidatingCallback = !isCandidateViable(CCC, EmptyCorrection); 3742 3743 // Perform name lookup to find visible, similarly-named entities. 3744 bool IsUnqualifiedLookup = false; 3745 DeclContext *QualifiedDC = MemberContext; 3746 if (MemberContext) { 3747 LookupVisibleDecls(MemberContext, LookupKind, Consumer); 3748 3749 // Look in qualified interfaces. 3750 if (OPT) { 3751 for (ObjCObjectPointerType::qual_iterator 3752 I = OPT->qual_begin(), E = OPT->qual_end(); 3753 I != E; ++I) 3754 LookupVisibleDecls(*I, LookupKind, Consumer); 3755 } 3756 } else if (SS && SS->isSet()) { 3757 QualifiedDC = computeDeclContext(*SS, EnteringContext); 3758 if (!QualifiedDC) 3759 return TypoCorrection(); 3760 3761 // Provide a stop gap for files that are just seriously broken. Trying 3762 // to correct all typos can turn into a HUGE performance penalty, causing 3763 // some files to take minutes to get rejected by the parser. 3764 if (TyposCorrected + UnqualifiedTyposCorrected.size() >= 20) 3765 return TypoCorrection(); 3766 ++TyposCorrected; 3767 3768 LookupVisibleDecls(QualifiedDC, LookupKind, Consumer); 3769 } else { 3770 IsUnqualifiedLookup = true; 3771 UnqualifiedTyposCorrectedMap::iterator Cached 3772 = UnqualifiedTyposCorrected.find(Typo); 3773 if (Cached != UnqualifiedTyposCorrected.end()) { 3774 // Add the cached value, unless it's a keyword or fails validation. In the 3775 // keyword case, we'll end up adding the keyword below. 3776 if (Cached->second) { 3777 if (!Cached->second.isKeyword() && 3778 isCandidateViable(CCC, Cached->second)) 3779 Consumer.addCorrection(Cached->second); 3780 } else { 3781 // Only honor no-correction cache hits when a callback that will validate 3782 // correction candidates is not being used. 3783 if (!ValidatingCallback) 3784 return TypoCorrection(); 3785 } 3786 } 3787 if (Cached == UnqualifiedTyposCorrected.end()) { 3788 // Provide a stop gap for files that are just seriously broken. Trying 3789 // to correct all typos can turn into a HUGE performance penalty, causing 3790 // some files to take minutes to get rejected by the parser. 3791 if (TyposCorrected + UnqualifiedTyposCorrected.size() >= 20) 3792 return TypoCorrection(); 3793 } 3794 } 3795 3796 // Determine whether we are going to search in the various namespaces for 3797 // corrections. 3798 bool SearchNamespaces 3799 = getLangOpts().CPlusPlus && 3800 (IsUnqualifiedLookup || (QualifiedDC && QualifiedDC->isNamespace())); 3801 // In a few cases we *only* want to search for corrections bases on just 3802 // adding or changing the nested name specifier. 3803 bool AllowOnlyNNSChanges = Typo->getName().size() < 3; 3804 3805 if (IsUnqualifiedLookup || SearchNamespaces) { 3806 // For unqualified lookup, look through all of the names that we have 3807 // seen in this translation unit. 3808 // FIXME: Re-add the ability to skip very unlikely potential corrections. 3809 for (IdentifierTable::iterator I = Context.Idents.begin(), 3810 IEnd = Context.Idents.end(); 3811 I != IEnd; ++I) 3812 Consumer.FoundName(I->getKey()); 3813 3814 // Walk through identifiers in external identifier sources. 3815 // FIXME: Re-add the ability to skip very unlikely potential corrections. 3816 if (IdentifierInfoLookup *External 3817 = Context.Idents.getExternalIdentifierLookup()) { 3818 OwningPtr<IdentifierIterator> Iter(External->getIdentifiers()); 3819 do { 3820 StringRef Name = Iter->Next(); 3821 if (Name.empty()) 3822 break; 3823 3824 Consumer.FoundName(Name); 3825 } while (true); 3826 } 3827 } 3828 3829 AddKeywordsToConsumer(*this, Consumer, S, CCC, SS && SS->isNotEmpty()); 3830 3831 // If we haven't found anything, we're done. 3832 if (Consumer.empty()) { 3833 // If this was an unqualified lookup, note that no correction was found. 3834 if (IsUnqualifiedLookup) 3835 (void)UnqualifiedTyposCorrected[Typo]; 3836 3837 return TypoCorrection(); 3838 } 3839 3840 // Make sure the best edit distance (prior to adding any namespace qualifiers) 3841 // is not more that about a third of the length of the typo's identifier. 3842 unsigned ED = Consumer.getBestEditDistance(true); 3843 if (ED > 0 && Typo->getName().size() / ED < 3) { 3844 // If this was an unqualified lookup, note that no correction was found. 3845 if (IsUnqualifiedLookup) 3846 (void)UnqualifiedTyposCorrected[Typo]; 3847 3848 return TypoCorrection(); 3849 } 3850 3851 // Build the NestedNameSpecifiers for the KnownNamespaces, if we're going 3852 // to search those namespaces. 3853 if (SearchNamespaces) { 3854 // Load any externally-known namespaces. 3855 if (ExternalSource && !LoadedExternalKnownNamespaces) { 3856 SmallVector<NamespaceDecl *, 4> ExternalKnownNamespaces; 3857 LoadedExternalKnownNamespaces = true; 3858 ExternalSource->ReadKnownNamespaces(ExternalKnownNamespaces); 3859 for (unsigned I = 0, N = ExternalKnownNamespaces.size(); I != N; ++I) 3860 KnownNamespaces[ExternalKnownNamespaces[I]] = true; 3861 } 3862 3863 for (llvm::DenseMap<NamespaceDecl*, bool>::iterator 3864 KNI = KnownNamespaces.begin(), 3865 KNIEnd = KnownNamespaces.end(); 3866 KNI != KNIEnd; ++KNI) 3867 Namespaces.AddNamespace(KNI->first); 3868 } 3869 3870 // Weed out any names that could not be found by name lookup or, if a 3871 // CorrectionCandidateCallback object was provided, failed validation. 3872 llvm::SmallVector<TypoCorrection, 16> QualifiedResults; 3873 LookupResult TmpRes(*this, TypoName, LookupKind); 3874 TmpRes.suppressDiagnostics(); 3875 while (!Consumer.empty()) { 3876 TypoCorrectionConsumer::distance_iterator DI = Consumer.begin(); 3877 unsigned ED = DI->first; 3878 for (TypoCorrectionConsumer::result_iterator I = DI->second.begin(), 3879 IEnd = DI->second.end(); 3880 I != IEnd; /* Increment in loop. */) { 3881 // If we only want nested name specifier corrections, ignore potential 3882 // corrections that have a different base identifier from the typo. 3883 if (AllowOnlyNNSChanges && 3884 I->second.front().getCorrectionAsIdentifierInfo() != Typo) { 3885 TypoCorrectionConsumer::result_iterator Prev = I; 3886 ++I; 3887 DI->second.erase(Prev); 3888 continue; 3889 } 3890 3891 // If the item already has been looked up or is a keyword, keep it. 3892 // If a validator callback object was given, drop the correction 3893 // unless it passes validation. 3894 bool Viable = false; 3895 for (TypoResultList::iterator RI = I->second.begin(); 3896 RI != I->second.end(); /* Increment in loop. */) { 3897 TypoResultList::iterator Prev = RI; 3898 ++RI; 3899 if (Prev->isResolved()) { 3900 if (!isCandidateViable(CCC, *Prev)) 3901 RI = I->second.erase(Prev); 3902 else 3903 Viable = true; 3904 } 3905 } 3906 if (Viable || I->second.empty()) { 3907 TypoCorrectionConsumer::result_iterator Prev = I; 3908 ++I; 3909 if (!Viable) 3910 DI->second.erase(Prev); 3911 continue; 3912 } 3913 assert(I->second.size() == 1 && "Expected a single unresolved candidate"); 3914 3915 // Perform name lookup on this name. 3916 TypoCorrection &Candidate = I->second.front(); 3917 IdentifierInfo *Name = Candidate.getCorrectionAsIdentifierInfo(); 3918 LookupPotentialTypoResult(*this, TmpRes, Name, S, SS, MemberContext, 3919 EnteringContext, CCC.IsObjCIvarLookup); 3920 3921 switch (TmpRes.getResultKind()) { 3922 case LookupResult::NotFound: 3923 case LookupResult::NotFoundInCurrentInstantiation: 3924 case LookupResult::FoundUnresolvedValue: 3925 QualifiedResults.push_back(Candidate); 3926 // We didn't find this name in our scope, or didn't like what we found; 3927 // ignore it. 3928 { 3929 TypoCorrectionConsumer::result_iterator Next = I; 3930 ++Next; 3931 DI->second.erase(I); 3932 I = Next; 3933 } 3934 break; 3935 3936 case LookupResult::Ambiguous: 3937 // We don't deal with ambiguities. 3938 return TypoCorrection(); 3939 3940 case LookupResult::FoundOverloaded: { 3941 TypoCorrectionConsumer::result_iterator Prev = I; 3942 // Store all of the Decls for overloaded symbols 3943 for (LookupResult::iterator TRD = TmpRes.begin(), 3944 TRDEnd = TmpRes.end(); 3945 TRD != TRDEnd; ++TRD) 3946 Candidate.addCorrectionDecl(*TRD); 3947 ++I; 3948 if (!isCandidateViable(CCC, Candidate)) 3949 DI->second.erase(Prev); 3950 break; 3951 } 3952 3953 case LookupResult::Found: { 3954 TypoCorrectionConsumer::result_iterator Prev = I; 3955 Candidate.setCorrectionDecl(TmpRes.getAsSingle<NamedDecl>()); 3956 ++I; 3957 if (!isCandidateViable(CCC, Candidate)) 3958 DI->second.erase(Prev); 3959 break; 3960 } 3961 3962 } 3963 } 3964 3965 if (DI->second.empty()) 3966 Consumer.erase(DI); 3967 else if (!getLangOpts().CPlusPlus || QualifiedResults.empty() || !ED) 3968 // If there are results in the closest possible bucket, stop 3969 break; 3970 3971 // Only perform the qualified lookups for C++ 3972 if (SearchNamespaces) { 3973 TmpRes.suppressDiagnostics(); 3974 for (llvm::SmallVector<TypoCorrection, 3975 16>::iterator QRI = QualifiedResults.begin(), 3976 QRIEnd = QualifiedResults.end(); 3977 QRI != QRIEnd; ++QRI) { 3978 for (NamespaceSpecifierSet::iterator NI = Namespaces.begin(), 3979 NIEnd = Namespaces.end(); 3980 NI != NIEnd; ++NI) { 3981 DeclContext *Ctx = NI->DeclCtx; 3982 3983 // FIXME: Stop searching once the namespaces are too far away to create 3984 // acceptable corrections for this identifier (since the namespaces 3985 // are sorted in ascending order by edit distance). 3986 3987 TmpRes.clear(); 3988 TmpRes.setLookupName(QRI->getCorrectionAsIdentifierInfo()); 3989 if (!LookupQualifiedName(TmpRes, Ctx)) continue; 3990 3991 // Any corrections added below will be validated in subsequent 3992 // iterations of the main while() loop over the Consumer's contents. 3993 switch (TmpRes.getResultKind()) { 3994 case LookupResult::Found: { 3995 TypoCorrection TC(*QRI); 3996 TC.setCorrectionDecl(TmpRes.getAsSingle<NamedDecl>()); 3997 TC.setCorrectionSpecifier(NI->NameSpecifier); 3998 TC.setQualifierDistance(NI->EditDistance); 3999 Consumer.addCorrection(TC); 4000 break; 4001 } 4002 case LookupResult::FoundOverloaded: { 4003 TypoCorrection TC(*QRI); 4004 TC.setCorrectionSpecifier(NI->NameSpecifier); 4005 TC.setQualifierDistance(NI->EditDistance); 4006 for (LookupResult::iterator TRD = TmpRes.begin(), 4007 TRDEnd = TmpRes.end(); 4008 TRD != TRDEnd; ++TRD) 4009 TC.addCorrectionDecl(*TRD); 4010 Consumer.addCorrection(TC); 4011 break; 4012 } 4013 case LookupResult::NotFound: 4014 case LookupResult::NotFoundInCurrentInstantiation: 4015 case LookupResult::Ambiguous: 4016 case LookupResult::FoundUnresolvedValue: 4017 break; 4018 } 4019 } 4020 } 4021 } 4022 4023 QualifiedResults.clear(); 4024 } 4025 4026 // No corrections remain... 4027 if (Consumer.empty()) return TypoCorrection(); 4028 4029 TypoResultsMap &BestResults = Consumer.getBestResults(); 4030 ED = Consumer.getBestEditDistance(true); 4031 4032 if (!AllowOnlyNNSChanges && ED > 0 && Typo->getName().size() / ED < 3) { 4033 // If this was an unqualified lookup and we believe the callback 4034 // object wouldn't have filtered out possible corrections, note 4035 // that no correction was found. 4036 if (IsUnqualifiedLookup && !ValidatingCallback) 4037 (void)UnqualifiedTyposCorrected[Typo]; 4038 4039 return TypoCorrection(); 4040 } 4041 4042 // If only a single name remains, return that result. 4043 if (BestResults.size() == 1) { 4044 const TypoResultList &CorrectionList = BestResults.begin()->second; 4045 const TypoCorrection &Result = CorrectionList.front(); 4046 if (CorrectionList.size() != 1) return TypoCorrection(); 4047 4048 // Don't correct to a keyword that's the same as the typo; the keyword 4049 // wasn't actually in scope. 4050 if (ED == 0 && Result.isKeyword()) return TypoCorrection(); 4051 4052 // Record the correction for unqualified lookup. 4053 if (IsUnqualifiedLookup) 4054 UnqualifiedTyposCorrected[Typo] = Result; 4055 4056 TypoCorrection TC = Result; 4057 TC.setCorrectionRange(SS, TypoName); 4058 return TC; 4059 } 4060 else if (BestResults.size() > 1 4061 // Ugly hack equivalent to CTC == CTC_ObjCMessageReceiver; 4062 // WantObjCSuper is only true for CTC_ObjCMessageReceiver and for 4063 // some instances of CTC_Unknown, while WantRemainingKeywords is true 4064 // for CTC_Unknown but not for CTC_ObjCMessageReceiver. 4065 && CCC.WantObjCSuper && !CCC.WantRemainingKeywords 4066 && BestResults["super"].front().isKeyword()) { 4067 // Prefer 'super' when we're completing in a message-receiver 4068 // context. 4069 4070 // Don't correct to a keyword that's the same as the typo; the keyword 4071 // wasn't actually in scope. 4072 if (ED == 0) return TypoCorrection(); 4073 4074 // Record the correction for unqualified lookup. 4075 if (IsUnqualifiedLookup) 4076 UnqualifiedTyposCorrected[Typo] = BestResults["super"].front(); 4077 4078 TypoCorrection TC = BestResults["super"].front(); 4079 TC.setCorrectionRange(SS, TypoName); 4080 return TC; 4081 } 4082 4083 // If this was an unqualified lookup and we believe the callback object did 4084 // not filter out possible corrections, note that no correction was found. 4085 if (IsUnqualifiedLookup && !ValidatingCallback) 4086 (void)UnqualifiedTyposCorrected[Typo]; 4087 4088 return TypoCorrection(); 4089} 4090 4091void TypoCorrection::addCorrectionDecl(NamedDecl *CDecl) { 4092 if (!CDecl) return; 4093 4094 if (isKeyword()) 4095 CorrectionDecls.clear(); 4096 4097 CorrectionDecls.push_back(CDecl); 4098 4099 if (!CorrectionName) 4100 CorrectionName = CDecl->getDeclName(); 4101} 4102 4103std::string TypoCorrection::getAsString(const LangOptions &LO) const { 4104 if (CorrectionNameSpec) { 4105 std::string tmpBuffer; 4106 llvm::raw_string_ostream PrefixOStream(tmpBuffer); 4107 CorrectionNameSpec->print(PrefixOStream, PrintingPolicy(LO)); 4108 CorrectionName.printName(PrefixOStream); 4109 return PrefixOStream.str(); 4110 } 4111 4112 return CorrectionName.getAsString(); 4113} 4114