SemaCXXScopeSpec.cpp revision 245431
1//===--- SemaCXXScopeSpec.cpp - Semantic Analysis for C++ scope specifiers-===// 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 C++ semantic analysis for scope specifiers. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Lookup.h" 16#include "clang/Sema/Template.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclTemplate.h" 19#include "clang/AST/ExprCXX.h" 20#include "clang/AST/NestedNameSpecifier.h" 21#include "clang/Basic/PartialDiagnostic.h" 22#include "clang/Sema/DeclSpec.h" 23#include "TypeLocBuilder.h" 24#include "llvm/ADT/STLExtras.h" 25#include "llvm/Support/raw_ostream.h" 26using namespace clang; 27 28/// \brief Find the current instantiation that associated with the given type. 29static CXXRecordDecl *getCurrentInstantiationOf(QualType T, 30 DeclContext *CurContext) { 31 if (T.isNull()) 32 return 0; 33 34 const Type *Ty = T->getCanonicalTypeInternal().getTypePtr(); 35 if (const RecordType *RecordTy = dyn_cast<RecordType>(Ty)) { 36 CXXRecordDecl *Record = cast<CXXRecordDecl>(RecordTy->getDecl()); 37 if (!T->isDependentType()) 38 return Record; 39 40 // This may be a member of a class template or class template partial 41 // specialization. If it's part of the current semantic context, then it's 42 // an injected-class-name; 43 for (; !CurContext->isFileContext(); CurContext = CurContext->getParent()) 44 if (CurContext->Equals(Record)) 45 return Record; 46 47 return 0; 48 } else if (isa<InjectedClassNameType>(Ty)) 49 return cast<InjectedClassNameType>(Ty)->getDecl(); 50 else 51 return 0; 52} 53 54/// \brief Compute the DeclContext that is associated with the given type. 55/// 56/// \param T the type for which we are attempting to find a DeclContext. 57/// 58/// \returns the declaration context represented by the type T, 59/// or NULL if the declaration context cannot be computed (e.g., because it is 60/// dependent and not the current instantiation). 61DeclContext *Sema::computeDeclContext(QualType T) { 62 if (!T->isDependentType()) 63 if (const TagType *Tag = T->getAs<TagType>()) 64 return Tag->getDecl(); 65 66 return ::getCurrentInstantiationOf(T, CurContext); 67} 68 69/// \brief Compute the DeclContext that is associated with the given 70/// scope specifier. 71/// 72/// \param SS the C++ scope specifier as it appears in the source 73/// 74/// \param EnteringContext when true, we will be entering the context of 75/// this scope specifier, so we can retrieve the declaration context of a 76/// class template or class template partial specialization even if it is 77/// not the current instantiation. 78/// 79/// \returns the declaration context represented by the scope specifier @p SS, 80/// or NULL if the declaration context cannot be computed (e.g., because it is 81/// dependent and not the current instantiation). 82DeclContext *Sema::computeDeclContext(const CXXScopeSpec &SS, 83 bool EnteringContext) { 84 if (!SS.isSet() || SS.isInvalid()) 85 return 0; 86 87 NestedNameSpecifier *NNS 88 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 89 if (NNS->isDependent()) { 90 // If this nested-name-specifier refers to the current 91 // instantiation, return its DeclContext. 92 if (CXXRecordDecl *Record = getCurrentInstantiationOf(NNS)) 93 return Record; 94 95 if (EnteringContext) { 96 const Type *NNSType = NNS->getAsType(); 97 if (!NNSType) { 98 return 0; 99 } 100 101 // Look through type alias templates, per C++0x [temp.dep.type]p1. 102 NNSType = Context.getCanonicalType(NNSType); 103 if (const TemplateSpecializationType *SpecType 104 = NNSType->getAs<TemplateSpecializationType>()) { 105 // We are entering the context of the nested name specifier, so try to 106 // match the nested name specifier to either a primary class template 107 // or a class template partial specialization. 108 if (ClassTemplateDecl *ClassTemplate 109 = dyn_cast_or_null<ClassTemplateDecl>( 110 SpecType->getTemplateName().getAsTemplateDecl())) { 111 QualType ContextType 112 = Context.getCanonicalType(QualType(SpecType, 0)); 113 114 // If the type of the nested name specifier is the same as the 115 // injected class name of the named class template, we're entering 116 // into that class template definition. 117 QualType Injected 118 = ClassTemplate->getInjectedClassNameSpecialization(); 119 if (Context.hasSameType(Injected, ContextType)) 120 return ClassTemplate->getTemplatedDecl(); 121 122 // If the type of the nested name specifier is the same as the 123 // type of one of the class template's class template partial 124 // specializations, we're entering into the definition of that 125 // class template partial specialization. 126 if (ClassTemplatePartialSpecializationDecl *PartialSpec 127 = ClassTemplate->findPartialSpecialization(ContextType)) 128 return PartialSpec; 129 } 130 } else if (const RecordType *RecordT = NNSType->getAs<RecordType>()) { 131 // The nested name specifier refers to a member of a class template. 132 return RecordT->getDecl(); 133 } 134 } 135 136 return 0; 137 } 138 139 switch (NNS->getKind()) { 140 case NestedNameSpecifier::Identifier: 141 llvm_unreachable("Dependent nested-name-specifier has no DeclContext"); 142 143 case NestedNameSpecifier::Namespace: 144 return NNS->getAsNamespace(); 145 146 case NestedNameSpecifier::NamespaceAlias: 147 return NNS->getAsNamespaceAlias()->getNamespace(); 148 149 case NestedNameSpecifier::TypeSpec: 150 case NestedNameSpecifier::TypeSpecWithTemplate: { 151 const TagType *Tag = NNS->getAsType()->getAs<TagType>(); 152 assert(Tag && "Non-tag type in nested-name-specifier"); 153 return Tag->getDecl(); 154 } 155 156 case NestedNameSpecifier::Global: 157 return Context.getTranslationUnitDecl(); 158 } 159 160 llvm_unreachable("Invalid NestedNameSpecifier::Kind!"); 161} 162 163bool Sema::isDependentScopeSpecifier(const CXXScopeSpec &SS) { 164 if (!SS.isSet() || SS.isInvalid()) 165 return false; 166 167 NestedNameSpecifier *NNS 168 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 169 return NNS->isDependent(); 170} 171 172// \brief Determine whether this C++ scope specifier refers to an 173// unknown specialization, i.e., a dependent type that is not the 174// current instantiation. 175bool Sema::isUnknownSpecialization(const CXXScopeSpec &SS) { 176 if (!isDependentScopeSpecifier(SS)) 177 return false; 178 179 NestedNameSpecifier *NNS 180 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 181 return getCurrentInstantiationOf(NNS) == 0; 182} 183 184/// \brief If the given nested name specifier refers to the current 185/// instantiation, return the declaration that corresponds to that 186/// current instantiation (C++0x [temp.dep.type]p1). 187/// 188/// \param NNS a dependent nested name specifier. 189CXXRecordDecl *Sema::getCurrentInstantiationOf(NestedNameSpecifier *NNS) { 190 assert(getLangOpts().CPlusPlus && "Only callable in C++"); 191 assert(NNS->isDependent() && "Only dependent nested-name-specifier allowed"); 192 193 if (!NNS->getAsType()) 194 return 0; 195 196 QualType T = QualType(NNS->getAsType(), 0); 197 return ::getCurrentInstantiationOf(T, CurContext); 198} 199 200/// \brief Require that the context specified by SS be complete. 201/// 202/// If SS refers to a type, this routine checks whether the type is 203/// complete enough (or can be made complete enough) for name lookup 204/// into the DeclContext. A type that is not yet completed can be 205/// considered "complete enough" if it is a class/struct/union/enum 206/// that is currently being defined. Or, if we have a type that names 207/// a class template specialization that is not a complete type, we 208/// will attempt to instantiate that class template. 209bool Sema::RequireCompleteDeclContext(CXXScopeSpec &SS, 210 DeclContext *DC) { 211 assert(DC != 0 && "given null context"); 212 213 TagDecl *tag = dyn_cast<TagDecl>(DC); 214 215 // If this is a dependent type, then we consider it complete. 216 if (!tag || tag->isDependentContext()) 217 return false; 218 219 // If we're currently defining this type, then lookup into the 220 // type is okay: don't complain that it isn't complete yet. 221 QualType type = Context.getTypeDeclType(tag); 222 const TagType *tagType = type->getAs<TagType>(); 223 if (tagType && tagType->isBeingDefined()) 224 return false; 225 226 SourceLocation loc = SS.getLastQualifierNameLoc(); 227 if (loc.isInvalid()) loc = SS.getRange().getBegin(); 228 229 // The type must be complete. 230 if (RequireCompleteType(loc, type, diag::err_incomplete_nested_name_spec, 231 SS.getRange())) { 232 SS.SetInvalid(SS.getRange()); 233 return true; 234 } 235 236 // Fixed enum types are complete, but they aren't valid as scopes 237 // until we see a definition, so awkwardly pull out this special 238 // case. 239 const EnumType *enumType = dyn_cast_or_null<EnumType>(tagType); 240 if (!enumType || enumType->getDecl()->isCompleteDefinition()) 241 return false; 242 243 // Try to instantiate the definition, if this is a specialization of an 244 // enumeration temploid. 245 EnumDecl *ED = enumType->getDecl(); 246 if (EnumDecl *Pattern = ED->getInstantiatedFromMemberEnum()) { 247 MemberSpecializationInfo *MSI = ED->getMemberSpecializationInfo(); 248 if (MSI->getTemplateSpecializationKind() != TSK_ExplicitSpecialization) { 249 if (InstantiateEnum(loc, ED, Pattern, getTemplateInstantiationArgs(ED), 250 TSK_ImplicitInstantiation)) { 251 SS.SetInvalid(SS.getRange()); 252 return true; 253 } 254 return false; 255 } 256 } 257 258 Diag(loc, diag::err_incomplete_nested_name_spec) 259 << type << SS.getRange(); 260 SS.SetInvalid(SS.getRange()); 261 return true; 262} 263 264bool Sema::ActOnCXXGlobalScopeSpecifier(Scope *S, SourceLocation CCLoc, 265 CXXScopeSpec &SS) { 266 SS.MakeGlobal(Context, CCLoc); 267 return false; 268} 269 270/// \brief Determines whether the given declaration is an valid acceptable 271/// result for name lookup of a nested-name-specifier. 272bool Sema::isAcceptableNestedNameSpecifier(NamedDecl *SD) { 273 if (!SD) 274 return false; 275 276 // Namespace and namespace aliases are fine. 277 if (isa<NamespaceDecl>(SD) || isa<NamespaceAliasDecl>(SD)) 278 return true; 279 280 if (!isa<TypeDecl>(SD)) 281 return false; 282 283 // Determine whether we have a class (or, in C++11, an enum) or 284 // a typedef thereof. If so, build the nested-name-specifier. 285 QualType T = Context.getTypeDeclType(cast<TypeDecl>(SD)); 286 if (T->isDependentType()) 287 return true; 288 else if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(SD)) { 289 if (TD->getUnderlyingType()->isRecordType() || 290 (Context.getLangOpts().CPlusPlus0x && 291 TD->getUnderlyingType()->isEnumeralType())) 292 return true; 293 } else if (isa<RecordDecl>(SD) || 294 (Context.getLangOpts().CPlusPlus0x && isa<EnumDecl>(SD))) 295 return true; 296 297 return false; 298} 299 300/// \brief If the given nested-name-specifier begins with a bare identifier 301/// (e.g., Base::), perform name lookup for that identifier as a 302/// nested-name-specifier within the given scope, and return the result of that 303/// name lookup. 304NamedDecl *Sema::FindFirstQualifierInScope(Scope *S, NestedNameSpecifier *NNS) { 305 if (!S || !NNS) 306 return 0; 307 308 while (NNS->getPrefix()) 309 NNS = NNS->getPrefix(); 310 311 if (NNS->getKind() != NestedNameSpecifier::Identifier) 312 return 0; 313 314 LookupResult Found(*this, NNS->getAsIdentifier(), SourceLocation(), 315 LookupNestedNameSpecifierName); 316 LookupName(Found, S); 317 assert(!Found.isAmbiguous() && "Cannot handle ambiguities here yet"); 318 319 if (!Found.isSingleResult()) 320 return 0; 321 322 NamedDecl *Result = Found.getFoundDecl(); 323 if (isAcceptableNestedNameSpecifier(Result)) 324 return Result; 325 326 return 0; 327} 328 329bool Sema::isNonTypeNestedNameSpecifier(Scope *S, CXXScopeSpec &SS, 330 SourceLocation IdLoc, 331 IdentifierInfo &II, 332 ParsedType ObjectTypePtr) { 333 QualType ObjectType = GetTypeFromParser(ObjectTypePtr); 334 LookupResult Found(*this, &II, IdLoc, LookupNestedNameSpecifierName); 335 336 // Determine where to perform name lookup 337 DeclContext *LookupCtx = 0; 338 bool isDependent = false; 339 if (!ObjectType.isNull()) { 340 // This nested-name-specifier occurs in a member access expression, e.g., 341 // x->B::f, and we are looking into the type of the object. 342 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist"); 343 LookupCtx = computeDeclContext(ObjectType); 344 isDependent = ObjectType->isDependentType(); 345 } else if (SS.isSet()) { 346 // This nested-name-specifier occurs after another nested-name-specifier, 347 // so long into the context associated with the prior nested-name-specifier. 348 LookupCtx = computeDeclContext(SS, false); 349 isDependent = isDependentScopeSpecifier(SS); 350 Found.setContextRange(SS.getRange()); 351 } 352 353 if (LookupCtx) { 354 // Perform "qualified" name lookup into the declaration context we 355 // computed, which is either the type of the base of a member access 356 // expression or the declaration context associated with a prior 357 // nested-name-specifier. 358 359 // The declaration context must be complete. 360 if (!LookupCtx->isDependentContext() && 361 RequireCompleteDeclContext(SS, LookupCtx)) 362 return false; 363 364 LookupQualifiedName(Found, LookupCtx); 365 } else if (isDependent) { 366 return false; 367 } else { 368 LookupName(Found, S); 369 } 370 Found.suppressDiagnostics(); 371 372 if (NamedDecl *ND = Found.getAsSingle<NamedDecl>()) 373 return isa<NamespaceDecl>(ND) || isa<NamespaceAliasDecl>(ND); 374 375 return false; 376} 377 378namespace { 379 380// Callback to only accept typo corrections that can be a valid C++ member 381// intializer: either a non-static field member or a base class. 382class NestedNameSpecifierValidatorCCC : public CorrectionCandidateCallback { 383 public: 384 explicit NestedNameSpecifierValidatorCCC(Sema &SRef) 385 : SRef(SRef) {} 386 387 virtual bool ValidateCandidate(const TypoCorrection &candidate) { 388 return SRef.isAcceptableNestedNameSpecifier(candidate.getCorrectionDecl()); 389 } 390 391 private: 392 Sema &SRef; 393}; 394 395} 396 397/// \brief Build a new nested-name-specifier for "identifier::", as described 398/// by ActOnCXXNestedNameSpecifier. 399/// 400/// This routine differs only slightly from ActOnCXXNestedNameSpecifier, in 401/// that it contains an extra parameter \p ScopeLookupResult, which provides 402/// the result of name lookup within the scope of the nested-name-specifier 403/// that was computed at template definition time. 404/// 405/// If ErrorRecoveryLookup is true, then this call is used to improve error 406/// recovery. This means that it should not emit diagnostics, it should 407/// just return true on failure. It also means it should only return a valid 408/// scope if it *knows* that the result is correct. It should not return in a 409/// dependent context, for example. Nor will it extend \p SS with the scope 410/// specifier. 411bool Sema::BuildCXXNestedNameSpecifier(Scope *S, 412 IdentifierInfo &Identifier, 413 SourceLocation IdentifierLoc, 414 SourceLocation CCLoc, 415 QualType ObjectType, 416 bool EnteringContext, 417 CXXScopeSpec &SS, 418 NamedDecl *ScopeLookupResult, 419 bool ErrorRecoveryLookup) { 420 LookupResult Found(*this, &Identifier, IdentifierLoc, 421 LookupNestedNameSpecifierName); 422 423 // Determine where to perform name lookup 424 DeclContext *LookupCtx = 0; 425 bool isDependent = false; 426 if (!ObjectType.isNull()) { 427 // This nested-name-specifier occurs in a member access expression, e.g., 428 // x->B::f, and we are looking into the type of the object. 429 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist"); 430 LookupCtx = computeDeclContext(ObjectType); 431 isDependent = ObjectType->isDependentType(); 432 } else if (SS.isSet()) { 433 // This nested-name-specifier occurs after another nested-name-specifier, 434 // so look into the context associated with the prior nested-name-specifier. 435 LookupCtx = computeDeclContext(SS, EnteringContext); 436 isDependent = isDependentScopeSpecifier(SS); 437 Found.setContextRange(SS.getRange()); 438 } 439 440 441 bool ObjectTypeSearchedInScope = false; 442 if (LookupCtx) { 443 // Perform "qualified" name lookup into the declaration context we 444 // computed, which is either the type of the base of a member access 445 // expression or the declaration context associated with a prior 446 // nested-name-specifier. 447 448 // The declaration context must be complete. 449 if (!LookupCtx->isDependentContext() && 450 RequireCompleteDeclContext(SS, LookupCtx)) 451 return true; 452 453 LookupQualifiedName(Found, LookupCtx); 454 455 if (!ObjectType.isNull() && Found.empty()) { 456 // C++ [basic.lookup.classref]p4: 457 // If the id-expression in a class member access is a qualified-id of 458 // the form 459 // 460 // class-name-or-namespace-name::... 461 // 462 // the class-name-or-namespace-name following the . or -> operator is 463 // looked up both in the context of the entire postfix-expression and in 464 // the scope of the class of the object expression. If the name is found 465 // only in the scope of the class of the object expression, the name 466 // shall refer to a class-name. If the name is found only in the 467 // context of the entire postfix-expression, the name shall refer to a 468 // class-name or namespace-name. [...] 469 // 470 // Qualified name lookup into a class will not find a namespace-name, 471 // so we do not need to diagnose that case specifically. However, 472 // this qualified name lookup may find nothing. In that case, perform 473 // unqualified name lookup in the given scope (if available) or 474 // reconstruct the result from when name lookup was performed at template 475 // definition time. 476 if (S) 477 LookupName(Found, S); 478 else if (ScopeLookupResult) 479 Found.addDecl(ScopeLookupResult); 480 481 ObjectTypeSearchedInScope = true; 482 } 483 } else if (!isDependent) { 484 // Perform unqualified name lookup in the current scope. 485 LookupName(Found, S); 486 } 487 488 // If we performed lookup into a dependent context and did not find anything, 489 // that's fine: just build a dependent nested-name-specifier. 490 if (Found.empty() && isDependent && 491 !(LookupCtx && LookupCtx->isRecord() && 492 (!cast<CXXRecordDecl>(LookupCtx)->hasDefinition() || 493 !cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases()))) { 494 // Don't speculate if we're just trying to improve error recovery. 495 if (ErrorRecoveryLookup) 496 return true; 497 498 // We were not able to compute the declaration context for a dependent 499 // base object type or prior nested-name-specifier, so this 500 // nested-name-specifier refers to an unknown specialization. Just build 501 // a dependent nested-name-specifier. 502 SS.Extend(Context, &Identifier, IdentifierLoc, CCLoc); 503 return false; 504 } 505 506 // FIXME: Deal with ambiguities cleanly. 507 508 if (Found.empty() && !ErrorRecoveryLookup) { 509 // We haven't found anything, and we're not recovering from a 510 // different kind of error, so look for typos. 511 DeclarationName Name = Found.getLookupName(); 512 NestedNameSpecifierValidatorCCC Validator(*this); 513 TypoCorrection Corrected; 514 Found.clear(); 515 if ((Corrected = CorrectTypo(Found.getLookupNameInfo(), 516 Found.getLookupKind(), S, &SS, Validator, 517 LookupCtx, EnteringContext))) { 518 std::string CorrectedStr(Corrected.getAsString(getLangOpts())); 519 std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOpts())); 520 if (LookupCtx) 521 Diag(Found.getNameLoc(), diag::err_no_member_suggest) 522 << Name << LookupCtx << CorrectedQuotedStr << SS.getRange() 523 << FixItHint::CreateReplacement(Corrected.getCorrectionRange(), 524 CorrectedStr); 525 else 526 Diag(Found.getNameLoc(), diag::err_undeclared_var_use_suggest) 527 << Name << CorrectedQuotedStr 528 << FixItHint::CreateReplacement(Found.getNameLoc(), CorrectedStr); 529 530 if (NamedDecl *ND = Corrected.getCorrectionDecl()) { 531 Diag(ND->getLocation(), diag::note_previous_decl) << CorrectedQuotedStr; 532 Found.addDecl(ND); 533 } 534 Found.setLookupName(Corrected.getCorrection()); 535 } else { 536 Found.setLookupName(&Identifier); 537 } 538 } 539 540 NamedDecl *SD = Found.getAsSingle<NamedDecl>(); 541 if (isAcceptableNestedNameSpecifier(SD)) { 542 if (!ObjectType.isNull() && !ObjectTypeSearchedInScope && 543 !getLangOpts().CPlusPlus0x) { 544 // C++03 [basic.lookup.classref]p4: 545 // [...] If the name is found in both contexts, the 546 // class-name-or-namespace-name shall refer to the same entity. 547 // 548 // We already found the name in the scope of the object. Now, look 549 // into the current scope (the scope of the postfix-expression) to 550 // see if we can find the same name there. As above, if there is no 551 // scope, reconstruct the result from the template instantiation itself. 552 // 553 // Note that C++11 does *not* perform this redundant lookup. 554 NamedDecl *OuterDecl; 555 if (S) { 556 LookupResult FoundOuter(*this, &Identifier, IdentifierLoc, 557 LookupNestedNameSpecifierName); 558 LookupName(FoundOuter, S); 559 OuterDecl = FoundOuter.getAsSingle<NamedDecl>(); 560 } else 561 OuterDecl = ScopeLookupResult; 562 563 if (isAcceptableNestedNameSpecifier(OuterDecl) && 564 OuterDecl->getCanonicalDecl() != SD->getCanonicalDecl() && 565 (!isa<TypeDecl>(OuterDecl) || !isa<TypeDecl>(SD) || 566 !Context.hasSameType( 567 Context.getTypeDeclType(cast<TypeDecl>(OuterDecl)), 568 Context.getTypeDeclType(cast<TypeDecl>(SD))))) { 569 if (ErrorRecoveryLookup) 570 return true; 571 572 Diag(IdentifierLoc, 573 diag::err_nested_name_member_ref_lookup_ambiguous) 574 << &Identifier; 575 Diag(SD->getLocation(), diag::note_ambig_member_ref_object_type) 576 << ObjectType; 577 Diag(OuterDecl->getLocation(), diag::note_ambig_member_ref_scope); 578 579 // Fall through so that we'll pick the name we found in the object 580 // type, since that's probably what the user wanted anyway. 581 } 582 } 583 584 // If we're just performing this lookup for error-recovery purposes, 585 // don't extend the nested-name-specifier. Just return now. 586 if (ErrorRecoveryLookup) 587 return false; 588 589 if (NamespaceDecl *Namespace = dyn_cast<NamespaceDecl>(SD)) { 590 SS.Extend(Context, Namespace, IdentifierLoc, CCLoc); 591 return false; 592 } 593 594 if (NamespaceAliasDecl *Alias = dyn_cast<NamespaceAliasDecl>(SD)) { 595 SS.Extend(Context, Alias, IdentifierLoc, CCLoc); 596 return false; 597 } 598 599 QualType T = Context.getTypeDeclType(cast<TypeDecl>(SD)); 600 TypeLocBuilder TLB; 601 if (isa<InjectedClassNameType>(T)) { 602 InjectedClassNameTypeLoc InjectedTL 603 = TLB.push<InjectedClassNameTypeLoc>(T); 604 InjectedTL.setNameLoc(IdentifierLoc); 605 } else if (isa<RecordType>(T)) { 606 RecordTypeLoc RecordTL = TLB.push<RecordTypeLoc>(T); 607 RecordTL.setNameLoc(IdentifierLoc); 608 } else if (isa<TypedefType>(T)) { 609 TypedefTypeLoc TypedefTL = TLB.push<TypedefTypeLoc>(T); 610 TypedefTL.setNameLoc(IdentifierLoc); 611 } else if (isa<EnumType>(T)) { 612 EnumTypeLoc EnumTL = TLB.push<EnumTypeLoc>(T); 613 EnumTL.setNameLoc(IdentifierLoc); 614 } else if (isa<TemplateTypeParmType>(T)) { 615 TemplateTypeParmTypeLoc TemplateTypeTL 616 = TLB.push<TemplateTypeParmTypeLoc>(T); 617 TemplateTypeTL.setNameLoc(IdentifierLoc); 618 } else if (isa<UnresolvedUsingType>(T)) { 619 UnresolvedUsingTypeLoc UnresolvedTL 620 = TLB.push<UnresolvedUsingTypeLoc>(T); 621 UnresolvedTL.setNameLoc(IdentifierLoc); 622 } else if (isa<SubstTemplateTypeParmType>(T)) { 623 SubstTemplateTypeParmTypeLoc TL 624 = TLB.push<SubstTemplateTypeParmTypeLoc>(T); 625 TL.setNameLoc(IdentifierLoc); 626 } else if (isa<SubstTemplateTypeParmPackType>(T)) { 627 SubstTemplateTypeParmPackTypeLoc TL 628 = TLB.push<SubstTemplateTypeParmPackTypeLoc>(T); 629 TL.setNameLoc(IdentifierLoc); 630 } else { 631 llvm_unreachable("Unhandled TypeDecl node in nested-name-specifier"); 632 } 633 634 if (T->isEnumeralType()) 635 Diag(IdentifierLoc, diag::warn_cxx98_compat_enum_nested_name_spec); 636 637 SS.Extend(Context, SourceLocation(), TLB.getTypeLocInContext(Context, T), 638 CCLoc); 639 return false; 640 } 641 642 // Otherwise, we have an error case. If we don't want diagnostics, just 643 // return an error now. 644 if (ErrorRecoveryLookup) 645 return true; 646 647 // If we didn't find anything during our lookup, try again with 648 // ordinary name lookup, which can help us produce better error 649 // messages. 650 if (Found.empty()) { 651 Found.clear(LookupOrdinaryName); 652 LookupName(Found, S); 653 } 654 655 // In Microsoft mode, if we are within a templated function and we can't 656 // resolve Identifier, then extend the SS with Identifier. This will have 657 // the effect of resolving Identifier during template instantiation. 658 // The goal is to be able to resolve a function call whose 659 // nested-name-specifier is located inside a dependent base class. 660 // Example: 661 // 662 // class C { 663 // public: 664 // static void foo2() { } 665 // }; 666 // template <class T> class A { public: typedef C D; }; 667 // 668 // template <class T> class B : public A<T> { 669 // public: 670 // void foo() { D::foo2(); } 671 // }; 672 if (getLangOpts().MicrosoftExt) { 673 DeclContext *DC = LookupCtx ? LookupCtx : CurContext; 674 if (DC->isDependentContext() && DC->isFunctionOrMethod()) { 675 SS.Extend(Context, &Identifier, IdentifierLoc, CCLoc); 676 return false; 677 } 678 } 679 680 unsigned DiagID; 681 if (!Found.empty()) 682 DiagID = diag::err_expected_class_or_namespace; 683 else if (SS.isSet()) { 684 Diag(IdentifierLoc, diag::err_no_member) 685 << &Identifier << LookupCtx << SS.getRange(); 686 return true; 687 } else 688 DiagID = diag::err_undeclared_var_use; 689 690 if (SS.isSet()) 691 Diag(IdentifierLoc, DiagID) << &Identifier << SS.getRange(); 692 else 693 Diag(IdentifierLoc, DiagID) << &Identifier; 694 695 return true; 696} 697 698bool Sema::ActOnCXXNestedNameSpecifier(Scope *S, 699 IdentifierInfo &Identifier, 700 SourceLocation IdentifierLoc, 701 SourceLocation CCLoc, 702 ParsedType ObjectType, 703 bool EnteringContext, 704 CXXScopeSpec &SS) { 705 if (SS.isInvalid()) 706 return true; 707 708 return BuildCXXNestedNameSpecifier(S, Identifier, IdentifierLoc, CCLoc, 709 GetTypeFromParser(ObjectType), 710 EnteringContext, SS, 711 /*ScopeLookupResult=*/0, false); 712} 713 714bool Sema::ActOnCXXNestedNameSpecifierDecltype(CXXScopeSpec &SS, 715 const DeclSpec &DS, 716 SourceLocation ColonColonLoc) { 717 if (SS.isInvalid() || DS.getTypeSpecType() == DeclSpec::TST_error) 718 return true; 719 720 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype); 721 722 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc()); 723 if (!T->isDependentType() && !T->getAs<TagType>()) { 724 Diag(DS.getTypeSpecTypeLoc(), diag::err_expected_class) 725 << T << getLangOpts().CPlusPlus; 726 return true; 727 } 728 729 TypeLocBuilder TLB; 730 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T); 731 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc()); 732 SS.Extend(Context, SourceLocation(), TLB.getTypeLocInContext(Context, T), 733 ColonColonLoc); 734 return false; 735} 736 737/// IsInvalidUnlessNestedName - This method is used for error recovery 738/// purposes to determine whether the specified identifier is only valid as 739/// a nested name specifier, for example a namespace name. It is 740/// conservatively correct to always return false from this method. 741/// 742/// The arguments are the same as those passed to ActOnCXXNestedNameSpecifier. 743bool Sema::IsInvalidUnlessNestedName(Scope *S, CXXScopeSpec &SS, 744 IdentifierInfo &Identifier, 745 SourceLocation IdentifierLoc, 746 SourceLocation ColonLoc, 747 ParsedType ObjectType, 748 bool EnteringContext) { 749 if (SS.isInvalid()) 750 return false; 751 752 return !BuildCXXNestedNameSpecifier(S, Identifier, IdentifierLoc, ColonLoc, 753 GetTypeFromParser(ObjectType), 754 EnteringContext, SS, 755 /*ScopeLookupResult=*/0, true); 756} 757 758bool Sema::ActOnCXXNestedNameSpecifier(Scope *S, 759 CXXScopeSpec &SS, 760 SourceLocation TemplateKWLoc, 761 TemplateTy Template, 762 SourceLocation TemplateNameLoc, 763 SourceLocation LAngleLoc, 764 ASTTemplateArgsPtr TemplateArgsIn, 765 SourceLocation RAngleLoc, 766 SourceLocation CCLoc, 767 bool EnteringContext) { 768 if (SS.isInvalid()) 769 return true; 770 771 // Translate the parser's template argument list in our AST format. 772 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 773 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 774 775 if (DependentTemplateName *DTN = Template.get().getAsDependentTemplateName()){ 776 // Handle a dependent template specialization for which we cannot resolve 777 // the template name. 778 assert(DTN->getQualifier() 779 == static_cast<NestedNameSpecifier*>(SS.getScopeRep())); 780 QualType T = Context.getDependentTemplateSpecializationType(ETK_None, 781 DTN->getQualifier(), 782 DTN->getIdentifier(), 783 TemplateArgs); 784 785 // Create source-location information for this type. 786 TypeLocBuilder Builder; 787 DependentTemplateSpecializationTypeLoc SpecTL 788 = Builder.push<DependentTemplateSpecializationTypeLoc>(T); 789 SpecTL.setElaboratedKeywordLoc(SourceLocation()); 790 SpecTL.setQualifierLoc(SS.getWithLocInContext(Context)); 791 SpecTL.setTemplateKeywordLoc(TemplateKWLoc); 792 SpecTL.setTemplateNameLoc(TemplateNameLoc); 793 SpecTL.setLAngleLoc(LAngleLoc); 794 SpecTL.setRAngleLoc(RAngleLoc); 795 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I) 796 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo()); 797 798 SS.Extend(Context, TemplateKWLoc, Builder.getTypeLocInContext(Context, T), 799 CCLoc); 800 return false; 801 } 802 803 804 if (Template.get().getAsOverloadedTemplate() || 805 isa<FunctionTemplateDecl>(Template.get().getAsTemplateDecl())) { 806 SourceRange R(TemplateNameLoc, RAngleLoc); 807 if (SS.getRange().isValid()) 808 R.setBegin(SS.getRange().getBegin()); 809 810 Diag(CCLoc, diag::err_non_type_template_in_nested_name_specifier) 811 << Template.get() << R; 812 NoteAllFoundTemplates(Template.get()); 813 return true; 814 } 815 816 // We were able to resolve the template name to an actual template. 817 // Build an appropriate nested-name-specifier. 818 QualType T = CheckTemplateIdType(Template.get(), TemplateNameLoc, 819 TemplateArgs); 820 if (T.isNull()) 821 return true; 822 823 // Alias template specializations can produce types which are not valid 824 // nested name specifiers. 825 if (!T->isDependentType() && !T->getAs<TagType>()) { 826 Diag(TemplateNameLoc, diag::err_nested_name_spec_non_tag) << T; 827 NoteAllFoundTemplates(Template.get()); 828 return true; 829 } 830 831 // Provide source-location information for the template specialization type. 832 TypeLocBuilder Builder; 833 TemplateSpecializationTypeLoc SpecTL 834 = Builder.push<TemplateSpecializationTypeLoc>(T); 835 SpecTL.setTemplateKeywordLoc(TemplateKWLoc); 836 SpecTL.setTemplateNameLoc(TemplateNameLoc); 837 SpecTL.setLAngleLoc(LAngleLoc); 838 SpecTL.setRAngleLoc(RAngleLoc); 839 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I) 840 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo()); 841 842 843 SS.Extend(Context, TemplateKWLoc, Builder.getTypeLocInContext(Context, T), 844 CCLoc); 845 return false; 846} 847 848namespace { 849 /// \brief A structure that stores a nested-name-specifier annotation, 850 /// including both the nested-name-specifier 851 struct NestedNameSpecifierAnnotation { 852 NestedNameSpecifier *NNS; 853 }; 854} 855 856void *Sema::SaveNestedNameSpecifierAnnotation(CXXScopeSpec &SS) { 857 if (SS.isEmpty() || SS.isInvalid()) 858 return 0; 859 860 void *Mem = Context.Allocate((sizeof(NestedNameSpecifierAnnotation) + 861 SS.location_size()), 862 llvm::alignOf<NestedNameSpecifierAnnotation>()); 863 NestedNameSpecifierAnnotation *Annotation 864 = new (Mem) NestedNameSpecifierAnnotation; 865 Annotation->NNS = SS.getScopeRep(); 866 memcpy(Annotation + 1, SS.location_data(), SS.location_size()); 867 return Annotation; 868} 869 870void Sema::RestoreNestedNameSpecifierAnnotation(void *AnnotationPtr, 871 SourceRange AnnotationRange, 872 CXXScopeSpec &SS) { 873 if (!AnnotationPtr) { 874 SS.SetInvalid(AnnotationRange); 875 return; 876 } 877 878 NestedNameSpecifierAnnotation *Annotation 879 = static_cast<NestedNameSpecifierAnnotation *>(AnnotationPtr); 880 SS.Adopt(NestedNameSpecifierLoc(Annotation->NNS, Annotation + 1)); 881} 882 883bool Sema::ShouldEnterDeclaratorScope(Scope *S, const CXXScopeSpec &SS) { 884 assert(SS.isSet() && "Parser passed invalid CXXScopeSpec."); 885 886 NestedNameSpecifier *Qualifier = 887 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 888 889 // There are only two places a well-formed program may qualify a 890 // declarator: first, when defining a namespace or class member 891 // out-of-line, and second, when naming an explicitly-qualified 892 // friend function. The latter case is governed by 893 // C++03 [basic.lookup.unqual]p10: 894 // In a friend declaration naming a member function, a name used 895 // in the function declarator and not part of a template-argument 896 // in a template-id is first looked up in the scope of the member 897 // function's class. If it is not found, or if the name is part of 898 // a template-argument in a template-id, the look up is as 899 // described for unqualified names in the definition of the class 900 // granting friendship. 901 // i.e. we don't push a scope unless it's a class member. 902 903 switch (Qualifier->getKind()) { 904 case NestedNameSpecifier::Global: 905 case NestedNameSpecifier::Namespace: 906 case NestedNameSpecifier::NamespaceAlias: 907 // These are always namespace scopes. We never want to enter a 908 // namespace scope from anything but a file context. 909 return CurContext->getRedeclContext()->isFileContext(); 910 911 case NestedNameSpecifier::Identifier: 912 case NestedNameSpecifier::TypeSpec: 913 case NestedNameSpecifier::TypeSpecWithTemplate: 914 // These are never namespace scopes. 915 return true; 916 } 917 918 llvm_unreachable("Invalid NestedNameSpecifier::Kind!"); 919} 920 921/// ActOnCXXEnterDeclaratorScope - Called when a C++ scope specifier (global 922/// scope or nested-name-specifier) is parsed, part of a declarator-id. 923/// After this method is called, according to [C++ 3.4.3p3], names should be 924/// looked up in the declarator-id's scope, until the declarator is parsed and 925/// ActOnCXXExitDeclaratorScope is called. 926/// The 'SS' should be a non-empty valid CXXScopeSpec. 927bool Sema::ActOnCXXEnterDeclaratorScope(Scope *S, CXXScopeSpec &SS) { 928 assert(SS.isSet() && "Parser passed invalid CXXScopeSpec."); 929 930 if (SS.isInvalid()) return true; 931 932 DeclContext *DC = computeDeclContext(SS, true); 933 if (!DC) return true; 934 935 // Before we enter a declarator's context, we need to make sure that 936 // it is a complete declaration context. 937 if (!DC->isDependentContext() && RequireCompleteDeclContext(SS, DC)) 938 return true; 939 940 EnterDeclaratorContext(S, DC); 941 942 // Rebuild the nested name specifier for the new scope. 943 if (DC->isDependentContext()) 944 RebuildNestedNameSpecifierInCurrentInstantiation(SS); 945 946 return false; 947} 948 949/// ActOnCXXExitDeclaratorScope - Called when a declarator that previously 950/// invoked ActOnCXXEnterDeclaratorScope(), is finished. 'SS' is the same 951/// CXXScopeSpec that was passed to ActOnCXXEnterDeclaratorScope as well. 952/// Used to indicate that names should revert to being looked up in the 953/// defining scope. 954void Sema::ActOnCXXExitDeclaratorScope(Scope *S, const CXXScopeSpec &SS) { 955 assert(SS.isSet() && "Parser passed invalid CXXScopeSpec."); 956 if (SS.isInvalid()) 957 return; 958 assert(!SS.isInvalid() && computeDeclContext(SS, true) && 959 "exiting declarator scope we never really entered"); 960 ExitDeclaratorContext(S); 961} 962