1 //===--------------------- SemaLookup.cpp - Name Lookup ------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements name lookup for C, C++, Objective-C, and
13 //===----------------------------------------------------------------------===//
14 #include "clang/Sema/Lookup.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/ASTMutationListener.h"
17 #include "clang/AST/CXXInheritance.h"
18 #include "clang/AST/Decl.h"
19 #include "clang/AST/DeclCXX.h"
20 #include "clang/AST/DeclLookups.h"
21 #include "clang/AST/DeclObjC.h"
22 #include "clang/AST/DeclTemplate.h"
23 #include "clang/AST/Expr.h"
24 #include "clang/AST/ExprCXX.h"
25 #include "clang/Basic/Builtins.h"
26 #include "clang/Basic/LangOptions.h"
27 #include "clang/Lex/HeaderSearch.h"
28 #include "clang/Lex/ModuleLoader.h"
29 #include "clang/Lex/Preprocessor.h"
30 #include "clang/Sema/DeclSpec.h"
31 #include "clang/Sema/ExternalSemaSource.h"
32 #include "clang/Sema/Overload.h"
33 #include "clang/Sema/Scope.h"
34 #include "clang/Sema/ScopeInfo.h"
35 #include "clang/Sema/Sema.h"
36 #include "clang/Sema/SemaInternal.h"
37 #include "clang/Sema/TemplateDeduction.h"
38 #include "clang/Sema/TypoCorrection.h"
39 #include "llvm/ADT/STLExtras.h"
40 #include "llvm/ADT/SetVector.h"
41 #include "llvm/ADT/SmallPtrSet.h"
42 #include "llvm/ADT/StringMap.h"
43 #include "llvm/ADT/TinyPtrVector.h"
44 #include "llvm/ADT/edit_distance.h"
45 #include "llvm/Support/ErrorHandling.h"
55 using namespace clang;
59 class UnqualUsingEntry {
60 const DeclContext *Nominated;
61 const DeclContext *CommonAncestor;
64 UnqualUsingEntry(const DeclContext *Nominated,
65 const DeclContext *CommonAncestor)
66 : Nominated(Nominated), CommonAncestor(CommonAncestor) {
69 const DeclContext *getCommonAncestor() const {
70 return CommonAncestor;
73 const DeclContext *getNominatedNamespace() const {
77 // Sort by the pointer value of the common ancestor.
79 bool operator()(const UnqualUsingEntry &L, const UnqualUsingEntry &R) {
80 return L.getCommonAncestor() < R.getCommonAncestor();
83 bool operator()(const UnqualUsingEntry &E, const DeclContext *DC) {
84 return E.getCommonAncestor() < DC;
87 bool operator()(const DeclContext *DC, const UnqualUsingEntry &E) {
88 return DC < E.getCommonAncestor();
93 /// A collection of using directives, as used by C++ unqualified
95 class UnqualUsingDirectiveSet {
96 typedef SmallVector<UnqualUsingEntry, 8> ListTy;
99 llvm::SmallPtrSet<DeclContext*, 8> visited;
102 UnqualUsingDirectiveSet() {}
104 void visitScopeChain(Scope *S, Scope *InnermostFileScope) {
105 // C++ [namespace.udir]p1:
106 // During unqualified name lookup, the names appear as if they
107 // were declared in the nearest enclosing namespace which contains
108 // both the using-directive and the nominated namespace.
109 DeclContext *InnermostFileDC = InnermostFileScope->getEntity();
110 assert(InnermostFileDC && InnermostFileDC->isFileContext());
112 for (; S; S = S->getParent()) {
113 // C++ [namespace.udir]p1:
114 // A using-directive shall not appear in class scope, but may
115 // appear in namespace scope or in block scope.
116 DeclContext *Ctx = S->getEntity();
117 if (Ctx && Ctx->isFileContext()) {
119 } else if (!Ctx || Ctx->isFunctionOrMethod()) {
120 for (auto *I : S->using_directives())
121 visit(I, InnermostFileDC);
126 // Visits a context and collect all of its using directives
127 // recursively. Treats all using directives as if they were
128 // declared in the context.
130 // A given context is only every visited once, so it is important
131 // that contexts be visited from the inside out in order to get
132 // the effective DCs right.
133 void visit(DeclContext *DC, DeclContext *EffectiveDC) {
134 if (!visited.insert(DC).second)
137 addUsingDirectives(DC, EffectiveDC);
140 // Visits a using directive and collects all of its using
141 // directives recursively. Treats all using directives as if they
142 // were declared in the effective DC.
143 void visit(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) {
144 DeclContext *NS = UD->getNominatedNamespace();
145 if (!visited.insert(NS).second)
148 addUsingDirective(UD, EffectiveDC);
149 addUsingDirectives(NS, EffectiveDC);
152 // Adds all the using directives in a context (and those nominated
153 // by its using directives, transitively) as if they appeared in
154 // the given effective context.
155 void addUsingDirectives(DeclContext *DC, DeclContext *EffectiveDC) {
156 SmallVector<DeclContext*,4> queue;
158 for (auto UD : DC->using_directives()) {
159 DeclContext *NS = UD->getNominatedNamespace();
160 if (visited.insert(NS).second) {
161 addUsingDirective(UD, EffectiveDC);
169 DC = queue.pop_back_val();
173 // Add a using directive as if it had been declared in the given
174 // context. This helps implement C++ [namespace.udir]p3:
175 // The using-directive is transitive: if a scope contains a
176 // using-directive that nominates a second namespace that itself
177 // contains using-directives, the effect is as if the
178 // using-directives from the second namespace also appeared in
180 void addUsingDirective(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) {
181 // Find the common ancestor between the effective context and
182 // the nominated namespace.
183 DeclContext *Common = UD->getNominatedNamespace();
184 while (!Common->Encloses(EffectiveDC))
185 Common = Common->getParent();
186 Common = Common->getPrimaryContext();
188 list.push_back(UnqualUsingEntry(UD->getNominatedNamespace(), Common));
192 std::sort(list.begin(), list.end(), UnqualUsingEntry::Comparator());
195 typedef ListTy::const_iterator const_iterator;
197 const_iterator begin() const { return list.begin(); }
198 const_iterator end() const { return list.end(); }
200 llvm::iterator_range<const_iterator>
201 getNamespacesFor(DeclContext *DC) const {
202 return llvm::make_range(std::equal_range(begin(), end(),
203 DC->getPrimaryContext(),
204 UnqualUsingEntry::Comparator()));
209 // Retrieve the set of identifier namespaces that correspond to a
210 // specific kind of name lookup.
211 static inline unsigned getIDNS(Sema::LookupNameKind NameKind,
213 bool Redeclaration) {
216 case Sema::LookupObjCImplicitSelfParam:
217 case Sema::LookupOrdinaryName:
218 case Sema::LookupRedeclarationWithLinkage:
219 case Sema::LookupLocalFriendName:
220 IDNS = Decl::IDNS_Ordinary;
222 IDNS |= Decl::IDNS_Tag | Decl::IDNS_Member | Decl::IDNS_Namespace;
224 IDNS |= Decl::IDNS_TagFriend | Decl::IDNS_OrdinaryFriend;
227 IDNS |= Decl::IDNS_LocalExtern;
230 case Sema::LookupOperatorName:
231 // Operator lookup is its own crazy thing; it is not the same
232 // as (e.g.) looking up an operator name for redeclaration.
233 assert(!Redeclaration && "cannot do redeclaration operator lookup");
234 IDNS = Decl::IDNS_NonMemberOperator;
237 case Sema::LookupTagName:
239 IDNS = Decl::IDNS_Type;
241 // When looking for a redeclaration of a tag name, we add:
242 // 1) TagFriend to find undeclared friend decls
243 // 2) Namespace because they can't "overload" with tag decls.
244 // 3) Tag because it includes class templates, which can't
245 // "overload" with tag decls.
247 IDNS |= Decl::IDNS_Tag | Decl::IDNS_TagFriend | Decl::IDNS_Namespace;
249 IDNS = Decl::IDNS_Tag;
253 case Sema::LookupLabel:
254 IDNS = Decl::IDNS_Label;
257 case Sema::LookupMemberName:
258 IDNS = Decl::IDNS_Member;
260 IDNS |= Decl::IDNS_Tag | Decl::IDNS_Ordinary;
263 case Sema::LookupNestedNameSpecifierName:
264 IDNS = Decl::IDNS_Type | Decl::IDNS_Namespace;
267 case Sema::LookupNamespaceName:
268 IDNS = Decl::IDNS_Namespace;
271 case Sema::LookupUsingDeclName:
272 assert(Redeclaration && "should only be used for redecl lookup");
273 IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag | Decl::IDNS_Member |
274 Decl::IDNS_Using | Decl::IDNS_TagFriend | Decl::IDNS_OrdinaryFriend |
275 Decl::IDNS_LocalExtern;
278 case Sema::LookupObjCProtocolName:
279 IDNS = Decl::IDNS_ObjCProtocol;
282 case Sema::LookupAnyName:
283 IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag | Decl::IDNS_Member
284 | Decl::IDNS_Using | Decl::IDNS_Namespace | Decl::IDNS_ObjCProtocol
291 void LookupResult::configure() {
292 IDNS = getIDNS(LookupKind, getSema().getLangOpts().CPlusPlus,
293 isForRedeclaration());
295 // If we're looking for one of the allocation or deallocation
296 // operators, make sure that the implicitly-declared new and delete
297 // operators can be found.
298 switch (NameInfo.getName().getCXXOverloadedOperator()) {
302 case OO_Array_Delete:
303 getSema().DeclareGlobalNewDelete();
310 // Compiler builtins are always visible, regardless of where they end
311 // up being declared.
312 if (IdentifierInfo *Id = NameInfo.getName().getAsIdentifierInfo()) {
313 if (unsigned BuiltinID = Id->getBuiltinID()) {
314 if (!getSema().Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
320 bool LookupResult::sanity() const {
321 // This function is never called by NDEBUG builds.
322 assert(ResultKind != NotFound || Decls.size() == 0);
323 assert(ResultKind != Found || Decls.size() == 1);
324 assert(ResultKind != FoundOverloaded || Decls.size() > 1 ||
325 (Decls.size() == 1 &&
326 isa<FunctionTemplateDecl>((*begin())->getUnderlyingDecl())));
327 assert(ResultKind != FoundUnresolvedValue || sanityCheckUnresolved());
328 assert(ResultKind != Ambiguous || Decls.size() > 1 ||
329 (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects ||
330 Ambiguity == AmbiguousBaseSubobjectTypes)));
331 assert((Paths != nullptr) == (ResultKind == Ambiguous &&
332 (Ambiguity == AmbiguousBaseSubobjectTypes ||
333 Ambiguity == AmbiguousBaseSubobjects)));
337 // Necessary because CXXBasePaths is not complete in Sema.h
338 void LookupResult::deletePaths(CXXBasePaths *Paths) {
342 /// Get a representative context for a declaration such that two declarations
343 /// will have the same context if they were found within the same scope.
344 static DeclContext *getContextForScopeMatching(Decl *D) {
345 // For function-local declarations, use that function as the context. This
346 // doesn't account for scopes within the function; the caller must deal with
348 DeclContext *DC = D->getLexicalDeclContext();
349 if (DC->isFunctionOrMethod())
352 // Otherwise, look at the semantic context of the declaration. The
353 // declaration must have been found there.
354 return D->getDeclContext()->getRedeclContext();
357 /// Resolves the result kind of this lookup.
358 void LookupResult::resolveKind() {
359 unsigned N = Decls.size();
361 // Fast case: no possible ambiguity.
363 assert(ResultKind == NotFound || ResultKind == NotFoundInCurrentInstantiation);
367 // If there's a single decl, we need to examine it to decide what
368 // kind of lookup this is.
370 NamedDecl *D = (*Decls.begin())->getUnderlyingDecl();
371 if (isa<FunctionTemplateDecl>(D))
372 ResultKind = FoundOverloaded;
373 else if (isa<UnresolvedUsingValueDecl>(D))
374 ResultKind = FoundUnresolvedValue;
378 // Don't do any extra resolution if we've already resolved as ambiguous.
379 if (ResultKind == Ambiguous) return;
381 llvm::SmallPtrSet<NamedDecl*, 16> Unique;
382 llvm::SmallPtrSet<QualType, 16> UniqueTypes;
384 bool Ambiguous = false;
385 bool HasTag = false, HasFunction = false, HasNonFunction = false;
386 bool HasFunctionTemplate = false, HasUnresolved = false;
388 unsigned UniqueTagIndex = 0;
392 NamedDecl *D = Decls[I]->getUnderlyingDecl();
393 D = cast<NamedDecl>(D->getCanonicalDecl());
395 // Ignore an invalid declaration unless it's the only one left.
396 if (D->isInvalidDecl() && I < N-1) {
397 Decls[I] = Decls[--N];
401 // Redeclarations of types via typedef can occur both within a scope
402 // and, through using declarations and directives, across scopes. There is
403 // no ambiguity if they all refer to the same type, so unique based on the
405 if (TypeDecl *TD = dyn_cast<TypeDecl>(D)) {
406 if (!TD->getDeclContext()->isRecord()) {
407 QualType T = getSema().Context.getTypeDeclType(TD);
408 if (!UniqueTypes.insert(getSema().Context.getCanonicalType(T)).second) {
409 // The type is not unique; pull something off the back and continue
411 Decls[I] = Decls[--N];
417 if (!Unique.insert(D).second) {
418 // If it's not unique, pull something off the back (and
419 // continue at this index).
420 // FIXME: This is wrong. We need to take the more recent declaration in
421 // order to get the right type, default arguments, etc. We also need to
422 // prefer visible declarations to hidden ones (for redeclaration lookup
423 // in modules builds).
424 Decls[I] = Decls[--N];
428 // Otherwise, do some decl type analysis and then continue.
430 if (isa<UnresolvedUsingValueDecl>(D)) {
431 HasUnresolved = true;
432 } else if (isa<TagDecl>(D)) {
437 } else if (isa<FunctionTemplateDecl>(D)) {
439 HasFunctionTemplate = true;
440 } else if (isa<FunctionDecl>(D)) {
445 HasNonFunction = true;
450 // C++ [basic.scope.hiding]p2:
451 // A class name or enumeration name can be hidden by the name of
452 // an object, function, or enumerator declared in the same
453 // scope. If a class or enumeration name and an object, function,
454 // or enumerator are declared in the same scope (in any order)
455 // with the same name, the class or enumeration name is hidden
456 // wherever the object, function, or enumerator name is visible.
457 // But it's still an error if there are distinct tag types found,
458 // even if they're not visible. (ref?)
459 if (HideTags && HasTag && !Ambiguous &&
460 (HasFunction || HasNonFunction || HasUnresolved)) {
461 if (getContextForScopeMatching(Decls[UniqueTagIndex])->Equals(
462 getContextForScopeMatching(Decls[UniqueTagIndex ? 0 : N - 1])))
463 Decls[UniqueTagIndex] = Decls[--N];
470 if (HasNonFunction && (HasFunction || HasUnresolved))
474 setAmbiguous(LookupResult::AmbiguousReference);
475 else if (HasUnresolved)
476 ResultKind = LookupResult::FoundUnresolvedValue;
477 else if (N > 1 || HasFunctionTemplate)
478 ResultKind = LookupResult::FoundOverloaded;
480 ResultKind = LookupResult::Found;
483 void LookupResult::addDeclsFromBasePaths(const CXXBasePaths &P) {
484 CXXBasePaths::const_paths_iterator I, E;
485 for (I = P.begin(), E = P.end(); I != E; ++I)
486 for (DeclContext::lookup_iterator DI = I->Decls.begin(),
487 DE = I->Decls.end(); DI != DE; ++DI)
491 void LookupResult::setAmbiguousBaseSubobjects(CXXBasePaths &P) {
492 Paths = new CXXBasePaths;
494 addDeclsFromBasePaths(*Paths);
496 setAmbiguous(AmbiguousBaseSubobjects);
499 void LookupResult::setAmbiguousBaseSubobjectTypes(CXXBasePaths &P) {
500 Paths = new CXXBasePaths;
502 addDeclsFromBasePaths(*Paths);
504 setAmbiguous(AmbiguousBaseSubobjectTypes);
507 void LookupResult::print(raw_ostream &Out) {
508 Out << Decls.size() << " result(s)";
509 if (isAmbiguous()) Out << ", ambiguous";
510 if (Paths) Out << ", base paths present";
512 for (iterator I = begin(), E = end(); I != E; ++I) {
518 /// \brief Lookup a builtin function, when name lookup would otherwise
520 static bool LookupBuiltin(Sema &S, LookupResult &R) {
521 Sema::LookupNameKind NameKind = R.getLookupKind();
523 // If we didn't find a use of this identifier, and if the identifier
524 // corresponds to a compiler builtin, create the decl object for the builtin
525 // now, injecting it into translation unit scope, and return it.
526 if (NameKind == Sema::LookupOrdinaryName ||
527 NameKind == Sema::LookupRedeclarationWithLinkage) {
528 IdentifierInfo *II = R.getLookupName().getAsIdentifierInfo();
530 if (S.getLangOpts().CPlusPlus11 && S.getLangOpts().GNUMode &&
531 II == S.getFloat128Identifier()) {
532 // libstdc++4.7's type_traits expects type __float128 to exist, so
533 // insert a dummy type to make that header build in gnu++11 mode.
534 R.addDecl(S.getASTContext().getFloat128StubType());
538 // If this is a builtin on this (or all) targets, create the decl.
539 if (unsigned BuiltinID = II->getBuiltinID()) {
540 // In C++, we don't have any predefined library functions like
541 // 'malloc'. Instead, we'll just error.
542 if (S.getLangOpts().CPlusPlus &&
543 S.Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
546 if (NamedDecl *D = S.LazilyCreateBuiltin((IdentifierInfo *)II,
547 BuiltinID, S.TUScope,
548 R.isForRedeclaration(),
560 /// \brief Determine whether we can declare a special member function within
561 /// the class at this point.
562 static bool CanDeclareSpecialMemberFunction(const CXXRecordDecl *Class) {
563 // We need to have a definition for the class.
564 if (!Class->getDefinition() || Class->isDependentContext())
567 // We can't be in the middle of defining the class.
568 return !Class->isBeingDefined();
571 void Sema::ForceDeclarationOfImplicitMembers(CXXRecordDecl *Class) {
572 if (!CanDeclareSpecialMemberFunction(Class))
575 // If the default constructor has not yet been declared, do so now.
576 if (Class->needsImplicitDefaultConstructor())
577 DeclareImplicitDefaultConstructor(Class);
579 // If the copy constructor has not yet been declared, do so now.
580 if (Class->needsImplicitCopyConstructor())
581 DeclareImplicitCopyConstructor(Class);
583 // If the copy assignment operator has not yet been declared, do so now.
584 if (Class->needsImplicitCopyAssignment())
585 DeclareImplicitCopyAssignment(Class);
587 if (getLangOpts().CPlusPlus11) {
588 // If the move constructor has not yet been declared, do so now.
589 if (Class->needsImplicitMoveConstructor())
590 DeclareImplicitMoveConstructor(Class); // might not actually do it
592 // If the move assignment operator has not yet been declared, do so now.
593 if (Class->needsImplicitMoveAssignment())
594 DeclareImplicitMoveAssignment(Class); // might not actually do it
597 // If the destructor has not yet been declared, do so now.
598 if (Class->needsImplicitDestructor())
599 DeclareImplicitDestructor(Class);
602 /// \brief Determine whether this is the name of an implicitly-declared
603 /// special member function.
604 static bool isImplicitlyDeclaredMemberFunctionName(DeclarationName Name) {
605 switch (Name.getNameKind()) {
606 case DeclarationName::CXXConstructorName:
607 case DeclarationName::CXXDestructorName:
610 case DeclarationName::CXXOperatorName:
611 return Name.getCXXOverloadedOperator() == OO_Equal;
620 /// \brief If there are any implicit member functions with the given name
621 /// that need to be declared in the given declaration context, do so.
622 static void DeclareImplicitMemberFunctionsWithName(Sema &S,
623 DeclarationName Name,
624 const DeclContext *DC) {
628 switch (Name.getNameKind()) {
629 case DeclarationName::CXXConstructorName:
630 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
631 if (Record->getDefinition() && CanDeclareSpecialMemberFunction(Record)) {
632 CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record);
633 if (Record->needsImplicitDefaultConstructor())
634 S.DeclareImplicitDefaultConstructor(Class);
635 if (Record->needsImplicitCopyConstructor())
636 S.DeclareImplicitCopyConstructor(Class);
637 if (S.getLangOpts().CPlusPlus11 &&
638 Record->needsImplicitMoveConstructor())
639 S.DeclareImplicitMoveConstructor(Class);
643 case DeclarationName::CXXDestructorName:
644 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
645 if (Record->getDefinition() && Record->needsImplicitDestructor() &&
646 CanDeclareSpecialMemberFunction(Record))
647 S.DeclareImplicitDestructor(const_cast<CXXRecordDecl *>(Record));
650 case DeclarationName::CXXOperatorName:
651 if (Name.getCXXOverloadedOperator() != OO_Equal)
654 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) {
655 if (Record->getDefinition() && CanDeclareSpecialMemberFunction(Record)) {
656 CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record);
657 if (Record->needsImplicitCopyAssignment())
658 S.DeclareImplicitCopyAssignment(Class);
659 if (S.getLangOpts().CPlusPlus11 &&
660 Record->needsImplicitMoveAssignment())
661 S.DeclareImplicitMoveAssignment(Class);
671 // Adds all qualifying matches for a name within a decl context to the
672 // given lookup result. Returns true if any matches were found.
673 static bool LookupDirect(Sema &S, LookupResult &R, const DeclContext *DC) {
676 // Lazily declare C++ special member functions.
677 if (S.getLangOpts().CPlusPlus)
678 DeclareImplicitMemberFunctionsWithName(S, R.getLookupName(), DC);
680 // Perform lookup into this declaration context.
681 DeclContext::lookup_result DR = DC->lookup(R.getLookupName());
682 for (DeclContext::lookup_iterator I = DR.begin(), E = DR.end(); I != E;
685 if ((D = R.getAcceptableDecl(D))) {
691 if (!Found && DC->isTranslationUnit() && LookupBuiltin(S, R))
694 if (R.getLookupName().getNameKind()
695 != DeclarationName::CXXConversionFunctionName ||
696 R.getLookupName().getCXXNameType()->isDependentType() ||
697 !isa<CXXRecordDecl>(DC))
701 // A specialization of a conversion function template is not found by
702 // name lookup. Instead, any conversion function templates visible in the
703 // context of the use are considered. [...]
704 const CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
705 if (!Record->isCompleteDefinition())
708 for (CXXRecordDecl::conversion_iterator U = Record->conversion_begin(),
709 UEnd = Record->conversion_end(); U != UEnd; ++U) {
710 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(*U);
714 // When we're performing lookup for the purposes of redeclaration, just
715 // add the conversion function template. When we deduce template
716 // arguments for specializations, we'll end up unifying the return
717 // type of the new declaration with the type of the function template.
718 if (R.isForRedeclaration()) {
719 R.addDecl(ConvTemplate);
725 // [...] For each such operator, if argument deduction succeeds
726 // (14.9.2.3), the resulting specialization is used as if found by
729 // When referencing a conversion function for any purpose other than
730 // a redeclaration (such that we'll be building an expression with the
731 // result), perform template argument deduction and place the
732 // specialization into the result set. We do this to avoid forcing all
733 // callers to perform special deduction for conversion functions.
734 TemplateDeductionInfo Info(R.getNameLoc());
735 FunctionDecl *Specialization = nullptr;
737 const FunctionProtoType *ConvProto
738 = ConvTemplate->getTemplatedDecl()->getType()->getAs<FunctionProtoType>();
739 assert(ConvProto && "Nonsensical conversion function template type");
741 // Compute the type of the function that we would expect the conversion
742 // function to have, if it were to match the name given.
743 // FIXME: Calling convention!
744 FunctionProtoType::ExtProtoInfo EPI = ConvProto->getExtProtoInfo();
745 EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC_C);
746 EPI.ExceptionSpec = EST_None;
747 QualType ExpectedType
748 = R.getSema().Context.getFunctionType(R.getLookupName().getCXXNameType(),
751 // Perform template argument deduction against the type that we would
752 // expect the function to have.
753 if (R.getSema().DeduceTemplateArguments(ConvTemplate, nullptr, ExpectedType,
754 Specialization, Info)
755 == Sema::TDK_Success) {
756 R.addDecl(Specialization);
764 // Performs C++ unqualified lookup into the given file context.
766 CppNamespaceLookup(Sema &S, LookupResult &R, ASTContext &Context,
767 DeclContext *NS, UnqualUsingDirectiveSet &UDirs) {
769 assert(NS && NS->isFileContext() && "CppNamespaceLookup() requires namespace!");
771 // Perform direct name lookup into the LookupCtx.
772 bool Found = LookupDirect(S, R, NS);
774 // Perform direct name lookup into the namespaces nominated by the
775 // using directives whose common ancestor is this namespace.
776 for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(NS))
777 if (LookupDirect(S, R, UUE.getNominatedNamespace()))
785 static bool isNamespaceOrTranslationUnitScope(Scope *S) {
786 if (DeclContext *Ctx = S->getEntity())
787 return Ctx->isFileContext();
791 // Find the next outer declaration context from this scope. This
792 // routine actually returns the semantic outer context, which may
793 // differ from the lexical context (encoded directly in the Scope
794 // stack) when we are parsing a member of a class template. In this
795 // case, the second element of the pair will be true, to indicate that
796 // name lookup should continue searching in this semantic context when
797 // it leaves the current template parameter scope.
798 static std::pair<DeclContext *, bool> findOuterContext(Scope *S) {
799 DeclContext *DC = S->getEntity();
800 DeclContext *Lexical = nullptr;
801 for (Scope *OuterS = S->getParent(); OuterS;
802 OuterS = OuterS->getParent()) {
803 if (OuterS->getEntity()) {
804 Lexical = OuterS->getEntity();
809 // C++ [temp.local]p8:
810 // In the definition of a member of a class template that appears
811 // outside of the namespace containing the class template
812 // definition, the name of a template-parameter hides the name of
813 // a member of this namespace.
820 // template<class T> class B {
825 // template<class C> void N::B<C>::f(C) {
826 // C b; // C is the template parameter, not N::C
829 // In this example, the lexical context we return is the
830 // TranslationUnit, while the semantic context is the namespace N.
831 if (!Lexical || !DC || !S->getParent() ||
832 !S->getParent()->isTemplateParamScope())
833 return std::make_pair(Lexical, false);
835 // Find the outermost template parameter scope.
836 // For the example, this is the scope for the template parameters of
837 // template<class C>.
838 Scope *OutermostTemplateScope = S->getParent();
839 while (OutermostTemplateScope->getParent() &&
840 OutermostTemplateScope->getParent()->isTemplateParamScope())
841 OutermostTemplateScope = OutermostTemplateScope->getParent();
843 // Find the namespace context in which the original scope occurs. In
844 // the example, this is namespace N.
845 DeclContext *Semantic = DC;
846 while (!Semantic->isFileContext())
847 Semantic = Semantic->getParent();
849 // Find the declaration context just outside of the template
850 // parameter scope. This is the context in which the template is
851 // being lexically declaration (a namespace context). In the
852 // example, this is the global scope.
853 if (Lexical->isFileContext() && !Lexical->Equals(Semantic) &&
854 Lexical->Encloses(Semantic))
855 return std::make_pair(Semantic, true);
857 return std::make_pair(Lexical, false);
861 /// An RAII object to specify that we want to find block scope extern
863 struct FindLocalExternScope {
864 FindLocalExternScope(LookupResult &R)
865 : R(R), OldFindLocalExtern(R.getIdentifierNamespace() &
866 Decl::IDNS_LocalExtern) {
867 R.setFindLocalExtern(R.getIdentifierNamespace() & Decl::IDNS_Ordinary);
870 R.setFindLocalExtern(OldFindLocalExtern);
872 ~FindLocalExternScope() {
876 bool OldFindLocalExtern;
880 bool Sema::CppLookupName(LookupResult &R, Scope *S) {
881 assert(getLangOpts().CPlusPlus && "Can perform only C++ lookup");
883 DeclarationName Name = R.getLookupName();
884 Sema::LookupNameKind NameKind = R.getLookupKind();
886 // If this is the name of an implicitly-declared special member function,
887 // go through the scope stack to implicitly declare
888 if (isImplicitlyDeclaredMemberFunctionName(Name)) {
889 for (Scope *PreS = S; PreS; PreS = PreS->getParent())
890 if (DeclContext *DC = PreS->getEntity())
891 DeclareImplicitMemberFunctionsWithName(*this, Name, DC);
894 // Implicitly declare member functions with the name we're looking for, if in
895 // fact we are in a scope where it matters.
898 IdentifierResolver::iterator
899 I = IdResolver.begin(Name),
900 IEnd = IdResolver.end();
902 // First we lookup local scope.
903 // We don't consider using-directives, as per 7.3.4.p1 [namespace.udir]
904 // ...During unqualified name lookup (3.4.1), the names appear as if
905 // they were declared in the nearest enclosing namespace which contains
906 // both the using-directive and the nominated namespace.
907 // [Note: in this context, "contains" means "contains directly or
911 // namespace A { int i; }
915 // using namespace A;
916 // ++i; // finds local 'i', A::i appears at global scope
920 UnqualUsingDirectiveSet UDirs;
921 bool VisitedUsingDirectives = false;
922 bool LeftStartingScope = false;
923 DeclContext *OutsideOfTemplateParamDC = nullptr;
925 // When performing a scope lookup, we want to find local extern decls.
926 FindLocalExternScope FindLocals(R);
928 for (; S && !isNamespaceOrTranslationUnitScope(S); S = S->getParent()) {
929 DeclContext *Ctx = S->getEntity();
931 // Check whether the IdResolver has anything in this scope.
933 for (; I != IEnd && S->isDeclScope(*I); ++I) {
934 if (NamedDecl *ND = R.getAcceptableDecl(*I)) {
935 if (NameKind == LookupRedeclarationWithLinkage) {
936 // Determine whether this (or a previous) declaration is
938 if (!LeftStartingScope && !Initial->isDeclScope(*I))
939 LeftStartingScope = true;
941 // If we found something outside of our starting scope that
942 // does not have linkage, skip it. If it's a template parameter,
943 // we still find it, so we can diagnose the invalid redeclaration.
944 if (LeftStartingScope && !((*I)->hasLinkage()) &&
945 !(*I)->isTemplateParameter()) {
957 if (S->isClassScope())
958 if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(Ctx))
959 R.setNamingClass(Record);
963 if (NameKind == LookupLocalFriendName && !S->isClassScope()) {
964 // C++11 [class.friend]p11:
965 // If a friend declaration appears in a local class and the name
966 // specified is an unqualified name, a prior declaration is
967 // looked up without considering scopes that are outside the
968 // innermost enclosing non-class scope.
972 if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
973 S->getParent() && !S->getParent()->isTemplateParamScope()) {
974 // We've just searched the last template parameter scope and
975 // found nothing, so look into the contexts between the
976 // lexical and semantic declaration contexts returned by
977 // findOuterContext(). This implements the name lookup behavior
978 // of C++ [temp.local]p8.
979 Ctx = OutsideOfTemplateParamDC;
980 OutsideOfTemplateParamDC = nullptr;
984 DeclContext *OuterCtx;
985 bool SearchAfterTemplateScope;
986 std::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
987 if (SearchAfterTemplateScope)
988 OutsideOfTemplateParamDC = OuterCtx;
990 for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
991 // We do not directly look into transparent contexts, since
992 // those entities will be found in the nearest enclosing
993 // non-transparent context.
994 if (Ctx->isTransparentContext())
997 // We do not look directly into function or method contexts,
998 // since all of the local variables and parameters of the
999 // function/method are present within the Scope.
1000 if (Ctx->isFunctionOrMethod()) {
1001 // If we have an Objective-C instance method, look for ivars
1002 // in the corresponding interface.
1003 if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
1004 if (Method->isInstanceMethod() && Name.getAsIdentifierInfo())
1005 if (ObjCInterfaceDecl *Class = Method->getClassInterface()) {
1006 ObjCInterfaceDecl *ClassDeclared;
1007 if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(
1008 Name.getAsIdentifierInfo(),
1010 if (NamedDecl *ND = R.getAcceptableDecl(Ivar)) {
1022 // If this is a file context, we need to perform unqualified name
1023 // lookup considering using directives.
1024 if (Ctx->isFileContext()) {
1025 // If we haven't handled using directives yet, do so now.
1026 if (!VisitedUsingDirectives) {
1027 // Add using directives from this context up to the top level.
1028 for (DeclContext *UCtx = Ctx; UCtx; UCtx = UCtx->getParent()) {
1029 if (UCtx->isTransparentContext())
1032 UDirs.visit(UCtx, UCtx);
1035 // Find the innermost file scope, so we can add using directives
1036 // from local scopes.
1037 Scope *InnermostFileScope = S;
1038 while (InnermostFileScope &&
1039 !isNamespaceOrTranslationUnitScope(InnermostFileScope))
1040 InnermostFileScope = InnermostFileScope->getParent();
1041 UDirs.visitScopeChain(Initial, InnermostFileScope);
1045 VisitedUsingDirectives = true;
1048 if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs)) {
1056 // Perform qualified name lookup into this context.
1057 // FIXME: In some cases, we know that every name that could be found by
1058 // this qualified name lookup will also be on the identifier chain. For
1059 // example, inside a class without any base classes, we never need to
1060 // perform qualified lookup because all of the members are on top of the
1061 // identifier chain.
1062 if (LookupQualifiedName(R, Ctx, /*InUnqualifiedLookup=*/true))
1068 // Stop if we ran out of scopes.
1069 // FIXME: This really, really shouldn't be happening.
1070 if (!S) return false;
1072 // If we are looking for members, no need to look into global/namespace scope.
1073 if (NameKind == LookupMemberName)
1076 // Collect UsingDirectiveDecls in all scopes, and recursively all
1077 // nominated namespaces by those using-directives.
1079 // FIXME: Cache this sorted list in Scope structure, and DeclContext, so we
1080 // don't build it for each lookup!
1081 if (!VisitedUsingDirectives) {
1082 UDirs.visitScopeChain(Initial, S);
1086 // If we're not performing redeclaration lookup, do not look for local
1087 // extern declarations outside of a function scope.
1088 if (!R.isForRedeclaration())
1089 FindLocals.restore();
1091 // Lookup namespace scope, and global scope.
1092 // Unqualified name lookup in C++ requires looking into scopes
1093 // that aren't strictly lexical, and therefore we walk through the
1094 // context as well as walking through the scopes.
1095 for (; S; S = S->getParent()) {
1096 // Check whether the IdResolver has anything in this scope.
1098 for (; I != IEnd && S->isDeclScope(*I); ++I) {
1099 if (NamedDecl *ND = R.getAcceptableDecl(*I)) {
1100 // We found something. Look for anything else in our scope
1101 // with this same name and in an acceptable identifier
1102 // namespace, so that we can construct an overload set if we
1109 if (Found && S->isTemplateParamScope()) {
1114 DeclContext *Ctx = S->getEntity();
1115 if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
1116 S->getParent() && !S->getParent()->isTemplateParamScope()) {
1117 // We've just searched the last template parameter scope and
1118 // found nothing, so look into the contexts between the
1119 // lexical and semantic declaration contexts returned by
1120 // findOuterContext(). This implements the name lookup behavior
1121 // of C++ [temp.local]p8.
1122 Ctx = OutsideOfTemplateParamDC;
1123 OutsideOfTemplateParamDC = nullptr;
1127 DeclContext *OuterCtx;
1128 bool SearchAfterTemplateScope;
1129 std::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
1130 if (SearchAfterTemplateScope)
1131 OutsideOfTemplateParamDC = OuterCtx;
1133 for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
1134 // We do not directly look into transparent contexts, since
1135 // those entities will be found in the nearest enclosing
1136 // non-transparent context.
1137 if (Ctx->isTransparentContext())
1140 // If we have a context, and it's not a context stashed in the
1141 // template parameter scope for an out-of-line definition, also
1142 // look into that context.
1143 if (!(Found && S && S->isTemplateParamScope())) {
1144 assert(Ctx->isFileContext() &&
1145 "We should have been looking only at file context here already.");
1147 // Look into context considering using-directives.
1148 if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs))
1157 if (R.isForRedeclaration() && !Ctx->isTransparentContext())
1162 if (R.isForRedeclaration() && Ctx && !Ctx->isTransparentContext())
1169 /// \brief Find the declaration that a class temploid member specialization was
1170 /// instantiated from, or the member itself if it is an explicit specialization.
1171 static Decl *getInstantiatedFrom(Decl *D, MemberSpecializationInfo *MSInfo) {
1172 return MSInfo->isExplicitSpecialization() ? D : MSInfo->getInstantiatedFrom();
1175 Module *Sema::getOwningModule(Decl *Entity) {
1176 // If it's imported, grab its owning module.
1177 Module *M = Entity->getImportedOwningModule();
1178 if (M || !isa<NamedDecl>(Entity) || !cast<NamedDecl>(Entity)->isHidden())
1180 assert(!Entity->isFromASTFile() &&
1181 "hidden entity from AST file has no owning module");
1183 if (!getLangOpts().ModulesLocalVisibility) {
1184 // If we're not tracking visibility locally, the only way a declaration
1185 // can be hidden and local is if it's hidden because it's parent is (for
1186 // instance, maybe this is a lazily-declared special member of an imported
1188 auto *Parent = cast<NamedDecl>(Entity->getDeclContext());
1189 assert(Parent->isHidden() && "unexpectedly hidden decl");
1190 return getOwningModule(Parent);
1193 // It's local and hidden; grab or compute its owning module.
1194 M = Entity->getLocalOwningModule();
1198 if (auto *Containing =
1199 PP.getModuleContainingLocation(Entity->getLocation())) {
1201 } else if (Entity->isInvalidDecl() || Entity->getLocation().isInvalid()) {
1202 // Don't bother tracking visibility for invalid declarations with broken
1204 cast<NamedDecl>(Entity)->setHidden(false);
1206 // We need to assign a module to an entity that exists outside of any
1207 // module, so that we can hide it from modules that we textually enter.
1208 // Invent a fake module for all such entities.
1209 if (!CachedFakeTopLevelModule) {
1210 CachedFakeTopLevelModule =
1211 PP.getHeaderSearchInfo().getModuleMap().findOrCreateModule(
1212 "<top-level>", nullptr, false, false).first;
1214 auto &SrcMgr = PP.getSourceManager();
1215 SourceLocation StartLoc =
1216 SrcMgr.getLocForStartOfFile(SrcMgr.getMainFileID());
1218 VisibleModulesStack.empty() ? VisibleModules : VisibleModulesStack[0];
1219 TopLevel.setVisible(CachedFakeTopLevelModule, StartLoc);
1222 M = CachedFakeTopLevelModule;
1226 Entity->setLocalOwningModule(M);
1230 void Sema::makeMergedDefinitionVisible(NamedDecl *ND, SourceLocation Loc) {
1231 if (auto *M = PP.getModuleContainingLocation(Loc))
1232 Context.mergeDefinitionIntoModule(ND, M);
1234 // We're not building a module; just make the definition visible.
1235 ND->setHidden(false);
1237 // If ND is a template declaration, make the template parameters
1238 // visible too. They're not (necessarily) within a mergeable DeclContext.
1239 if (auto *TD = dyn_cast<TemplateDecl>(ND))
1240 for (auto *Param : *TD->getTemplateParameters())
1241 makeMergedDefinitionVisible(Param, Loc);
1244 /// \brief Find the module in which the given declaration was defined.
1245 static Module *getDefiningModule(Sema &S, Decl *Entity) {
1246 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Entity)) {
1247 // If this function was instantiated from a template, the defining module is
1248 // the module containing the pattern.
1249 if (FunctionDecl *Pattern = FD->getTemplateInstantiationPattern())
1251 } else if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Entity)) {
1252 if (CXXRecordDecl *Pattern = RD->getTemplateInstantiationPattern())
1254 } else if (EnumDecl *ED = dyn_cast<EnumDecl>(Entity)) {
1255 if (MemberSpecializationInfo *MSInfo = ED->getMemberSpecializationInfo())
1256 Entity = getInstantiatedFrom(ED, MSInfo);
1257 } else if (VarDecl *VD = dyn_cast<VarDecl>(Entity)) {
1258 // FIXME: Map from variable template specializations back to the template.
1259 if (MemberSpecializationInfo *MSInfo = VD->getMemberSpecializationInfo())
1260 Entity = getInstantiatedFrom(VD, MSInfo);
1263 // Walk up to the containing context. That might also have been instantiated
1265 DeclContext *Context = Entity->getDeclContext();
1266 if (Context->isFileContext())
1267 return S.getOwningModule(Entity);
1268 return getDefiningModule(S, cast<Decl>(Context));
1271 llvm::DenseSet<Module*> &Sema::getLookupModules() {
1272 unsigned N = ActiveTemplateInstantiations.size();
1273 for (unsigned I = ActiveTemplateInstantiationLookupModules.size();
1276 getDefiningModule(*this, ActiveTemplateInstantiations[I].Entity);
1277 if (M && !LookupModulesCache.insert(M).second)
1279 ActiveTemplateInstantiationLookupModules.push_back(M);
1281 return LookupModulesCache;
1284 bool Sema::hasVisibleMergedDefinition(NamedDecl *Def) {
1285 for (Module *Merged : Context.getModulesWithMergedDefinition(Def))
1286 if (isModuleVisible(Merged))
1291 template<typename ParmDecl>
1293 hasVisibleDefaultArgument(Sema &S, const ParmDecl *D,
1294 llvm::SmallVectorImpl<Module *> *Modules) {
1295 if (!D->hasDefaultArgument())
1299 auto &DefaultArg = D->getDefaultArgStorage();
1300 if (!DefaultArg.isInherited() && S.isVisible(D))
1303 if (!DefaultArg.isInherited() && Modules) {
1304 auto *NonConstD = const_cast<ParmDecl*>(D);
1305 Modules->push_back(S.getOwningModule(NonConstD));
1306 const auto &Merged = S.Context.getModulesWithMergedDefinition(NonConstD);
1307 Modules->insert(Modules->end(), Merged.begin(), Merged.end());
1310 // If there was a previous default argument, maybe its parameter is visible.
1311 D = DefaultArg.getInheritedFrom();
1316 bool Sema::hasVisibleDefaultArgument(const NamedDecl *D,
1317 llvm::SmallVectorImpl<Module *> *Modules) {
1318 if (auto *P = dyn_cast<TemplateTypeParmDecl>(D))
1319 return ::hasVisibleDefaultArgument(*this, P, Modules);
1320 if (auto *P = dyn_cast<NonTypeTemplateParmDecl>(D))
1321 return ::hasVisibleDefaultArgument(*this, P, Modules);
1322 return ::hasVisibleDefaultArgument(*this, cast<TemplateTemplateParmDecl>(D),
1326 /// \brief Determine whether a declaration is visible to name lookup.
1328 /// This routine determines whether the declaration D is visible in the current
1329 /// lookup context, taking into account the current template instantiation
1330 /// stack. During template instantiation, a declaration is visible if it is
1331 /// visible from a module containing any entity on the template instantiation
1332 /// path (by instantiating a template, you allow it to see the declarations that
1333 /// your module can see, including those later on in your module).
1334 bool LookupResult::isVisibleSlow(Sema &SemaRef, NamedDecl *D) {
1335 assert(D->isHidden() && "should not call this: not in slow case");
1336 Module *DeclModule = SemaRef.getOwningModule(D);
1338 // getOwningModule() may have decided the declaration should not be hidden.
1339 assert(!D->isHidden() && "hidden decl not from a module");
1343 // If the owning module is visible, and the decl is not module private,
1344 // then the decl is visible too. (Module private is ignored within the same
1345 // top-level module.)
1346 if (!D->isFromASTFile() || !D->isModulePrivate()) {
1347 if (SemaRef.isModuleVisible(DeclModule))
1349 // Also check merged definitions.
1350 if (SemaRef.getLangOpts().ModulesLocalVisibility &&
1351 SemaRef.hasVisibleMergedDefinition(D))
1355 // If this declaration is not at namespace scope nor module-private,
1356 // then it is visible if its lexical parent has a visible definition.
1357 DeclContext *DC = D->getLexicalDeclContext();
1358 if (!D->isModulePrivate() &&
1359 DC && !DC->isFileContext() && !isa<LinkageSpecDecl>(DC)) {
1360 // For a parameter, check whether our current template declaration's
1361 // lexical context is visible, not whether there's some other visible
1362 // definition of it, because parameters aren't "within" the definition.
1363 if ((D->isTemplateParameter() || isa<ParmVarDecl>(D))
1364 ? isVisible(SemaRef, cast<NamedDecl>(DC))
1365 : SemaRef.hasVisibleDefinition(cast<NamedDecl>(DC))) {
1366 if (SemaRef.ActiveTemplateInstantiations.empty() &&
1367 // FIXME: Do something better in this case.
1368 !SemaRef.getLangOpts().ModulesLocalVisibility) {
1369 // Cache the fact that this declaration is implicitly visible because
1370 // its parent has a visible definition.
1371 D->setHidden(false);
1378 // Find the extra places where we need to look.
1379 llvm::DenseSet<Module*> &LookupModules = SemaRef.getLookupModules();
1380 if (LookupModules.empty())
1383 // If our lookup set contains the decl's module, it's visible.
1384 if (LookupModules.count(DeclModule))
1387 // If the declaration isn't exported, it's not visible in any other module.
1388 if (D->isModulePrivate())
1391 // Check whether DeclModule is transitively exported to an import of
1393 for (llvm::DenseSet<Module *>::iterator I = LookupModules.begin(),
1394 E = LookupModules.end();
1396 if ((*I)->isModuleVisible(DeclModule))
1401 bool Sema::isVisibleSlow(const NamedDecl *D) {
1402 return LookupResult::isVisible(*this, const_cast<NamedDecl*>(D));
1405 /// \brief Retrieve the visible declaration corresponding to D, if any.
1407 /// This routine determines whether the declaration D is visible in the current
1408 /// module, with the current imports. If not, it checks whether any
1409 /// redeclaration of D is visible, and if so, returns that declaration.
1411 /// \returns D, or a visible previous declaration of D, whichever is more recent
1412 /// and visible. If no declaration of D is visible, returns null.
1413 static NamedDecl *findAcceptableDecl(Sema &SemaRef, NamedDecl *D) {
1414 assert(!LookupResult::isVisible(SemaRef, D) && "not in slow case");
1416 for (auto RD : D->redecls()) {
1417 if (auto ND = dyn_cast<NamedDecl>(RD)) {
1418 // FIXME: This is wrong in the case where the previous declaration is not
1419 // visible in the same scope as D. This needs to be done much more
1421 if (LookupResult::isVisible(SemaRef, ND))
1429 NamedDecl *LookupResult::getAcceptableDeclSlow(NamedDecl *D) const {
1430 return findAcceptableDecl(getSema(), D);
1433 /// @brief Perform unqualified name lookup starting from a given
1436 /// Unqualified name lookup (C++ [basic.lookup.unqual], C99 6.2.1) is
1437 /// used to find names within the current scope. For example, 'x' in
1441 /// return x; // unqualified name look finds 'x' in the global scope
1445 /// Different lookup criteria can find different names. For example, a
1446 /// particular scope can have both a struct and a function of the same
1447 /// name, and each can be found by certain lookup criteria. For more
1448 /// information about lookup criteria, see the documentation for the
1449 /// class LookupCriteria.
1451 /// @param S The scope from which unqualified name lookup will
1452 /// begin. If the lookup criteria permits, name lookup may also search
1453 /// in the parent scopes.
1455 /// @param [in,out] R Specifies the lookup to perform (e.g., the name to
1456 /// look up and the lookup kind), and is updated with the results of lookup
1457 /// including zero or more declarations and possibly additional information
1458 /// used to diagnose ambiguities.
1460 /// @returns \c true if lookup succeeded and false otherwise.
1461 bool Sema::LookupName(LookupResult &R, Scope *S, bool AllowBuiltinCreation) {
1462 DeclarationName Name = R.getLookupName();
1463 if (!Name) return false;
1465 LookupNameKind NameKind = R.getLookupKind();
1467 if (!getLangOpts().CPlusPlus) {
1468 // Unqualified name lookup in C/Objective-C is purely lexical, so
1469 // search in the declarations attached to the name.
1470 if (NameKind == Sema::LookupRedeclarationWithLinkage) {
1471 // Find the nearest non-transparent declaration scope.
1472 while (!(S->getFlags() & Scope::DeclScope) ||
1473 (S->getEntity() && S->getEntity()->isTransparentContext()))
1477 // When performing a scope lookup, we want to find local extern decls.
1478 FindLocalExternScope FindLocals(R);
1480 // Scan up the scope chain looking for a decl that matches this
1481 // identifier that is in the appropriate namespace. This search
1482 // should not take long, as shadowing of names is uncommon, and
1483 // deep shadowing is extremely uncommon.
1484 bool LeftStartingScope = false;
1486 for (IdentifierResolver::iterator I = IdResolver.begin(Name),
1487 IEnd = IdResolver.end();
1489 if (NamedDecl *D = R.getAcceptableDecl(*I)) {
1490 if (NameKind == LookupRedeclarationWithLinkage) {
1491 // Determine whether this (or a previous) declaration is
1493 if (!LeftStartingScope && !S->isDeclScope(*I))
1494 LeftStartingScope = true;
1496 // If we found something outside of our starting scope that
1497 // does not have linkage, skip it.
1498 if (LeftStartingScope && !((*I)->hasLinkage())) {
1503 else if (NameKind == LookupObjCImplicitSelfParam &&
1504 !isa<ImplicitParamDecl>(*I))
1509 // Check whether there are any other declarations with the same name
1510 // and in the same scope.
1512 // Find the scope in which this declaration was declared (if it
1513 // actually exists in a Scope).
1514 while (S && !S->isDeclScope(D))
1517 // If the scope containing the declaration is the translation unit,
1518 // then we'll need to perform our checks based on the matching
1519 // DeclContexts rather than matching scopes.
1520 if (S && isNamespaceOrTranslationUnitScope(S))
1523 // Compute the DeclContext, if we need it.
1524 DeclContext *DC = nullptr;
1526 DC = (*I)->getDeclContext()->getRedeclContext();
1528 IdentifierResolver::iterator LastI = I;
1529 for (++LastI; LastI != IEnd; ++LastI) {
1531 // Match based on scope.
1532 if (!S->isDeclScope(*LastI))
1535 // Match based on DeclContext.
1537 = (*LastI)->getDeclContext()->getRedeclContext();
1538 if (!LastDC->Equals(DC))
1542 // If the declaration is in the right namespace and visible, add it.
1543 if (NamedDecl *LastD = R.getAcceptableDecl(*LastI))
1553 // Perform C++ unqualified name lookup.
1554 if (CppLookupName(R, S))
1558 // If we didn't find a use of this identifier, and if the identifier
1559 // corresponds to a compiler builtin, create the decl object for the builtin
1560 // now, injecting it into translation unit scope, and return it.
1561 if (AllowBuiltinCreation && LookupBuiltin(*this, R))
1564 // If we didn't find a use of this identifier, the ExternalSource
1565 // may be able to handle the situation.
1566 // Note: some lookup failures are expected!
1567 // See e.g. R.isForRedeclaration().
1568 return (ExternalSource && ExternalSource->LookupUnqualified(R, S));
1571 /// @brief Perform qualified name lookup in the namespaces nominated by
1572 /// using directives by the given context.
1574 /// C++98 [namespace.qual]p2:
1575 /// Given X::m (where X is a user-declared namespace), or given \::m
1576 /// (where X is the global namespace), let S be the set of all
1577 /// declarations of m in X and in the transitive closure of all
1578 /// namespaces nominated by using-directives in X and its used
1579 /// namespaces, except that using-directives are ignored in any
1580 /// namespace, including X, directly containing one or more
1581 /// declarations of m. No namespace is searched more than once in
1582 /// the lookup of a name. If S is the empty set, the program is
1583 /// ill-formed. Otherwise, if S has exactly one member, or if the
1584 /// context of the reference is a using-declaration
1585 /// (namespace.udecl), S is the required set of declarations of
1586 /// m. Otherwise if the use of m is not one that allows a unique
1587 /// declaration to be chosen from S, the program is ill-formed.
1589 /// C++98 [namespace.qual]p5:
1590 /// During the lookup of a qualified namespace member name, if the
1591 /// lookup finds more than one declaration of the member, and if one
1592 /// declaration introduces a class name or enumeration name and the
1593 /// other declarations either introduce the same object, the same
1594 /// enumerator or a set of functions, the non-type name hides the
1595 /// class or enumeration name if and only if the declarations are
1596 /// from the same namespace; otherwise (the declarations are from
1597 /// different namespaces), the program is ill-formed.
1598 static bool LookupQualifiedNameInUsingDirectives(Sema &S, LookupResult &R,
1599 DeclContext *StartDC) {
1600 assert(StartDC->isFileContext() && "start context is not a file context");
1602 DeclContext::udir_range UsingDirectives = StartDC->using_directives();
1603 if (UsingDirectives.begin() == UsingDirectives.end()) return false;
1605 // We have at least added all these contexts to the queue.
1606 llvm::SmallPtrSet<DeclContext*, 8> Visited;
1607 Visited.insert(StartDC);
1609 // We have not yet looked into these namespaces, much less added
1610 // their "using-children" to the queue.
1611 SmallVector<NamespaceDecl*, 8> Queue;
1613 // We have already looked into the initial namespace; seed the queue
1614 // with its using-children.
1615 for (auto *I : UsingDirectives) {
1616 NamespaceDecl *ND = I->getNominatedNamespace()->getOriginalNamespace();
1617 if (Visited.insert(ND).second)
1618 Queue.push_back(ND);
1621 // The easiest way to implement the restriction in [namespace.qual]p5
1622 // is to check whether any of the individual results found a tag
1623 // and, if so, to declare an ambiguity if the final result is not
1625 bool FoundTag = false;
1626 bool FoundNonTag = false;
1628 LookupResult LocalR(LookupResult::Temporary, R);
1631 while (!Queue.empty()) {
1632 NamespaceDecl *ND = Queue.pop_back_val();
1634 // We go through some convolutions here to avoid copying results
1635 // between LookupResults.
1636 bool UseLocal = !R.empty();
1637 LookupResult &DirectR = UseLocal ? LocalR : R;
1638 bool FoundDirect = LookupDirect(S, DirectR, ND);
1641 // First do any local hiding.
1642 DirectR.resolveKind();
1644 // If the local result is a tag, remember that.
1645 if (DirectR.isSingleTagDecl())
1650 // Append the local results to the total results if necessary.
1652 R.addAllDecls(LocalR);
1657 // If we find names in this namespace, ignore its using directives.
1663 for (auto I : ND->using_directives()) {
1664 NamespaceDecl *Nom = I->getNominatedNamespace();
1665 if (Visited.insert(Nom).second)
1666 Queue.push_back(Nom);
1671 if (FoundTag && FoundNonTag)
1672 R.setAmbiguousQualifiedTagHiding();
1680 /// \brief Callback that looks for any member of a class with the given name.
1681 static bool LookupAnyMember(const CXXBaseSpecifier *Specifier,
1684 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl();
1686 DeclarationName N = DeclarationName::getFromOpaquePtr(Name);
1687 Path.Decls = BaseRecord->lookup(N);
1688 return !Path.Decls.empty();
1691 /// \brief Determine whether the given set of member declarations contains only
1692 /// static members, nested types, and enumerators.
1693 template<typename InputIterator>
1694 static bool HasOnlyStaticMembers(InputIterator First, InputIterator Last) {
1695 Decl *D = (*First)->getUnderlyingDecl();
1696 if (isa<VarDecl>(D) || isa<TypeDecl>(D) || isa<EnumConstantDecl>(D))
1699 if (isa<CXXMethodDecl>(D)) {
1700 // Determine whether all of the methods are static.
1701 bool AllMethodsAreStatic = true;
1702 for(; First != Last; ++First) {
1703 D = (*First)->getUnderlyingDecl();
1705 if (!isa<CXXMethodDecl>(D)) {
1706 assert(isa<TagDecl>(D) && "Non-function must be a tag decl");
1710 if (!cast<CXXMethodDecl>(D)->isStatic()) {
1711 AllMethodsAreStatic = false;
1716 if (AllMethodsAreStatic)
1723 /// \brief Perform qualified name lookup into a given context.
1725 /// Qualified name lookup (C++ [basic.lookup.qual]) is used to find
1726 /// names when the context of those names is explicit specified, e.g.,
1727 /// "std::vector" or "x->member", or as part of unqualified name lookup.
1729 /// Different lookup criteria can find different names. For example, a
1730 /// particular scope can have both a struct and a function of the same
1731 /// name, and each can be found by certain lookup criteria. For more
1732 /// information about lookup criteria, see the documentation for the
1733 /// class LookupCriteria.
1735 /// \param R captures both the lookup criteria and any lookup results found.
1737 /// \param LookupCtx The context in which qualified name lookup will
1738 /// search. If the lookup criteria permits, name lookup may also search
1739 /// in the parent contexts or (for C++ classes) base classes.
1741 /// \param InUnqualifiedLookup true if this is qualified name lookup that
1742 /// occurs as part of unqualified name lookup.
1744 /// \returns true if lookup succeeded, false if it failed.
1745 bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
1746 bool InUnqualifiedLookup) {
1747 assert(LookupCtx && "Sema::LookupQualifiedName requires a lookup context");
1749 if (!R.getLookupName())
1752 // Make sure that the declaration context is complete.
1753 assert((!isa<TagDecl>(LookupCtx) ||
1754 LookupCtx->isDependentContext() ||
1755 cast<TagDecl>(LookupCtx)->isCompleteDefinition() ||
1756 cast<TagDecl>(LookupCtx)->isBeingDefined()) &&
1757 "Declaration context must already be complete!");
1759 // Perform qualified name lookup into the LookupCtx.
1760 if (LookupDirect(*this, R, LookupCtx)) {
1762 if (isa<CXXRecordDecl>(LookupCtx))
1763 R.setNamingClass(cast<CXXRecordDecl>(LookupCtx));
1767 // Don't descend into implied contexts for redeclarations.
1768 // C++98 [namespace.qual]p6:
1769 // In a declaration for a namespace member in which the
1770 // declarator-id is a qualified-id, given that the qualified-id
1771 // for the namespace member has the form
1772 // nested-name-specifier unqualified-id
1773 // the unqualified-id shall name a member of the namespace
1774 // designated by the nested-name-specifier.
1775 // See also [class.mfct]p5 and [class.static.data]p2.
1776 if (R.isForRedeclaration())
1779 // If this is a namespace, look it up in the implied namespaces.
1780 if (LookupCtx->isFileContext())
1781 return LookupQualifiedNameInUsingDirectives(*this, R, LookupCtx);
1783 // If this isn't a C++ class, we aren't allowed to look into base
1784 // classes, we're done.
1785 CXXRecordDecl *LookupRec = dyn_cast<CXXRecordDecl>(LookupCtx);
1786 if (!LookupRec || !LookupRec->getDefinition())
1789 // If we're performing qualified name lookup into a dependent class,
1790 // then we are actually looking into a current instantiation. If we have any
1791 // dependent base classes, then we either have to delay lookup until
1792 // template instantiation time (at which point all bases will be available)
1793 // or we have to fail.
1794 if (!InUnqualifiedLookup && LookupRec->isDependentContext() &&
1795 LookupRec->hasAnyDependentBases()) {
1796 R.setNotFoundInCurrentInstantiation();
1800 // Perform lookup into our base classes.
1802 Paths.setOrigin(LookupRec);
1804 // Look for this member in our base classes
1805 CXXRecordDecl::BaseMatchesCallback *BaseCallback = nullptr;
1806 switch (R.getLookupKind()) {
1807 case LookupObjCImplicitSelfParam:
1808 case LookupOrdinaryName:
1809 case LookupMemberName:
1810 case LookupRedeclarationWithLinkage:
1811 case LookupLocalFriendName:
1812 BaseCallback = &CXXRecordDecl::FindOrdinaryMember;
1816 BaseCallback = &CXXRecordDecl::FindTagMember;
1820 BaseCallback = &LookupAnyMember;
1823 case LookupUsingDeclName:
1824 // This lookup is for redeclarations only.
1826 case LookupOperatorName:
1827 case LookupNamespaceName:
1828 case LookupObjCProtocolName:
1830 // These lookups will never find a member in a C++ class (or base class).
1833 case LookupNestedNameSpecifierName:
1834 BaseCallback = &CXXRecordDecl::FindNestedNameSpecifierMember;
1838 if (!LookupRec->lookupInBases(BaseCallback,
1839 R.getLookupName().getAsOpaquePtr(), Paths))
1842 R.setNamingClass(LookupRec);
1844 // C++ [class.member.lookup]p2:
1845 // [...] If the resulting set of declarations are not all from
1846 // sub-objects of the same type, or the set has a nonstatic member
1847 // and includes members from distinct sub-objects, there is an
1848 // ambiguity and the program is ill-formed. Otherwise that set is
1849 // the result of the lookup.
1850 QualType SubobjectType;
1851 int SubobjectNumber = 0;
1852 AccessSpecifier SubobjectAccess = AS_none;
1854 for (CXXBasePaths::paths_iterator Path = Paths.begin(), PathEnd = Paths.end();
1855 Path != PathEnd; ++Path) {
1856 const CXXBasePathElement &PathElement = Path->back();
1858 // Pick the best (i.e. most permissive i.e. numerically lowest) access
1859 // across all paths.
1860 SubobjectAccess = std::min(SubobjectAccess, Path->Access);
1862 // Determine whether we're looking at a distinct sub-object or not.
1863 if (SubobjectType.isNull()) {
1864 // This is the first subobject we've looked at. Record its type.
1865 SubobjectType = Context.getCanonicalType(PathElement.Base->getType());
1866 SubobjectNumber = PathElement.SubobjectNumber;
1871 != Context.getCanonicalType(PathElement.Base->getType())) {
1872 // We found members of the given name in two subobjects of
1873 // different types. If the declaration sets aren't the same, this
1874 // lookup is ambiguous.
1875 if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end())) {
1876 CXXBasePaths::paths_iterator FirstPath = Paths.begin();
1877 DeclContext::lookup_iterator FirstD = FirstPath->Decls.begin();
1878 DeclContext::lookup_iterator CurrentD = Path->Decls.begin();
1880 while (FirstD != FirstPath->Decls.end() &&
1881 CurrentD != Path->Decls.end()) {
1882 if ((*FirstD)->getUnderlyingDecl()->getCanonicalDecl() !=
1883 (*CurrentD)->getUnderlyingDecl()->getCanonicalDecl())
1890 if (FirstD == FirstPath->Decls.end() &&
1891 CurrentD == Path->Decls.end())
1895 R.setAmbiguousBaseSubobjectTypes(Paths);
1899 if (SubobjectNumber != PathElement.SubobjectNumber) {
1900 // We have a different subobject of the same type.
1902 // C++ [class.member.lookup]p5:
1903 // A static member, a nested type or an enumerator defined in
1904 // a base class T can unambiguously be found even if an object
1905 // has more than one base class subobject of type T.
1906 if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end()))
1909 // We have found a nonstatic member name in multiple, distinct
1910 // subobjects. Name lookup is ambiguous.
1911 R.setAmbiguousBaseSubobjects(Paths);
1916 // Lookup in a base class succeeded; return these results.
1918 for (auto *D : Paths.front().Decls) {
1919 AccessSpecifier AS = CXXRecordDecl::MergeAccess(SubobjectAccess,
1927 /// \brief Performs qualified name lookup or special type of lookup for
1928 /// "__super::" scope specifier.
1930 /// This routine is a convenience overload meant to be called from contexts
1931 /// that need to perform a qualified name lookup with an optional C++ scope
1932 /// specifier that might require special kind of lookup.
1934 /// \param R captures both the lookup criteria and any lookup results found.
1936 /// \param LookupCtx The context in which qualified name lookup will
1939 /// \param SS An optional C++ scope-specifier.
1941 /// \returns true if lookup succeeded, false if it failed.
1942 bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
1944 auto *NNS = SS.getScopeRep();
1945 if (NNS && NNS->getKind() == NestedNameSpecifier::Super)
1946 return LookupInSuper(R, NNS->getAsRecordDecl());
1949 return LookupQualifiedName(R, LookupCtx);
1952 /// @brief Performs name lookup for a name that was parsed in the
1953 /// source code, and may contain a C++ scope specifier.
1955 /// This routine is a convenience routine meant to be called from
1956 /// contexts that receive a name and an optional C++ scope specifier
1957 /// (e.g., "N::M::x"). It will then perform either qualified or
1958 /// unqualified name lookup (with LookupQualifiedName or LookupName,
1959 /// respectively) on the given name and return those results. It will
1960 /// perform a special type of lookup for "__super::" scope specifier.
1962 /// @param S The scope from which unqualified name lookup will
1965 /// @param SS An optional C++ scope-specifier, e.g., "::N::M".
1967 /// @param EnteringContext Indicates whether we are going to enter the
1968 /// context of the scope-specifier SS (if present).
1970 /// @returns True if any decls were found (but possibly ambiguous)
1971 bool Sema::LookupParsedName(LookupResult &R, Scope *S, CXXScopeSpec *SS,
1972 bool AllowBuiltinCreation, bool EnteringContext) {
1973 if (SS && SS->isInvalid()) {
1974 // When the scope specifier is invalid, don't even look for
1979 if (SS && SS->isSet()) {
1980 NestedNameSpecifier *NNS = SS->getScopeRep();
1981 if (NNS->getKind() == NestedNameSpecifier::Super)
1982 return LookupInSuper(R, NNS->getAsRecordDecl());
1984 if (DeclContext *DC = computeDeclContext(*SS, EnteringContext)) {
1985 // We have resolved the scope specifier to a particular declaration
1986 // contex, and will perform name lookup in that context.
1987 if (!DC->isDependentContext() && RequireCompleteDeclContext(*SS, DC))
1990 R.setContextRange(SS->getRange());
1991 return LookupQualifiedName(R, DC);
1994 // We could not resolve the scope specified to a specific declaration
1995 // context, which means that SS refers to an unknown specialization.
1996 // Name lookup can't find anything in this case.
1997 R.setNotFoundInCurrentInstantiation();
1998 R.setContextRange(SS->getRange());
2002 // Perform unqualified name lookup starting in the given scope.
2003 return LookupName(R, S, AllowBuiltinCreation);
2006 /// \brief Perform qualified name lookup into all base classes of the given
2009 /// \param R captures both the lookup criteria and any lookup results found.
2011 /// \param Class The context in which qualified name lookup will
2012 /// search. Name lookup will search in all base classes merging the results.
2014 /// @returns True if any decls were found (but possibly ambiguous)
2015 bool Sema::LookupInSuper(LookupResult &R, CXXRecordDecl *Class) {
2016 for (const auto &BaseSpec : Class->bases()) {
2017 CXXRecordDecl *RD = cast<CXXRecordDecl>(
2018 BaseSpec.getType()->castAs<RecordType>()->getDecl());
2019 LookupResult Result(*this, R.getLookupNameInfo(), R.getLookupKind());
2020 Result.setBaseObjectType(Context.getRecordType(Class));
2021 LookupQualifiedName(Result, RD);
2022 for (auto *Decl : Result)
2031 /// \brief Produce a diagnostic describing the ambiguity that resulted
2032 /// from name lookup.
2034 /// \param Result The result of the ambiguous lookup to be diagnosed.
2035 void Sema::DiagnoseAmbiguousLookup(LookupResult &Result) {
2036 assert(Result.isAmbiguous() && "Lookup result must be ambiguous");
2038 DeclarationName Name = Result.getLookupName();
2039 SourceLocation NameLoc = Result.getNameLoc();
2040 SourceRange LookupRange = Result.getContextRange();
2042 switch (Result.getAmbiguityKind()) {
2043 case LookupResult::AmbiguousBaseSubobjects: {
2044 CXXBasePaths *Paths = Result.getBasePaths();
2045 QualType SubobjectType = Paths->front().back().Base->getType();
2046 Diag(NameLoc, diag::err_ambiguous_member_multiple_subobjects)
2047 << Name << SubobjectType << getAmbiguousPathsDisplayString(*Paths)
2050 DeclContext::lookup_iterator Found = Paths->front().Decls.begin();
2051 while (isa<CXXMethodDecl>(*Found) &&
2052 cast<CXXMethodDecl>(*Found)->isStatic())
2055 Diag((*Found)->getLocation(), diag::note_ambiguous_member_found);
2059 case LookupResult::AmbiguousBaseSubobjectTypes: {
2060 Diag(NameLoc, diag::err_ambiguous_member_multiple_subobject_types)
2061 << Name << LookupRange;
2063 CXXBasePaths *Paths = Result.getBasePaths();
2064 std::set<Decl *> DeclsPrinted;
2065 for (CXXBasePaths::paths_iterator Path = Paths->begin(),
2066 PathEnd = Paths->end();
2067 Path != PathEnd; ++Path) {
2068 Decl *D = Path->Decls.front();
2069 if (DeclsPrinted.insert(D).second)
2070 Diag(D->getLocation(), diag::note_ambiguous_member_found);
2075 case LookupResult::AmbiguousTagHiding: {
2076 Diag(NameLoc, diag::err_ambiguous_tag_hiding) << Name << LookupRange;
2078 llvm::SmallPtrSet<NamedDecl*,8> TagDecls;
2080 for (auto *D : Result)
2081 if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
2082 TagDecls.insert(TD);
2083 Diag(TD->getLocation(), diag::note_hidden_tag);
2086 for (auto *D : Result)
2087 if (!isa<TagDecl>(D))
2088 Diag(D->getLocation(), diag::note_hiding_object);
2090 // For recovery purposes, go ahead and implement the hiding.
2091 LookupResult::Filter F = Result.makeFilter();
2092 while (F.hasNext()) {
2093 if (TagDecls.count(F.next()))
2100 case LookupResult::AmbiguousReference: {
2101 Diag(NameLoc, diag::err_ambiguous_reference) << Name << LookupRange;
2103 for (auto *D : Result)
2104 Diag(D->getLocation(), diag::note_ambiguous_candidate) << D;
2111 struct AssociatedLookup {
2112 AssociatedLookup(Sema &S, SourceLocation InstantiationLoc,
2113 Sema::AssociatedNamespaceSet &Namespaces,
2114 Sema::AssociatedClassSet &Classes)
2115 : S(S), Namespaces(Namespaces), Classes(Classes),
2116 InstantiationLoc(InstantiationLoc) {
2120 Sema::AssociatedNamespaceSet &Namespaces;
2121 Sema::AssociatedClassSet &Classes;
2122 SourceLocation InstantiationLoc;
2127 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType T);
2129 static void CollectEnclosingNamespace(Sema::AssociatedNamespaceSet &Namespaces,
2131 // Add the associated namespace for this class.
2133 // We don't use DeclContext::getEnclosingNamespaceContext() as this may
2134 // be a locally scoped record.
2136 // We skip out of inline namespaces. The innermost non-inline namespace
2137 // contains all names of all its nested inline namespaces anyway, so we can
2138 // replace the entire inline namespace tree with its root.
2139 while (Ctx->isRecord() || Ctx->isTransparentContext() ||
2140 Ctx->isInlineNamespace())
2141 Ctx = Ctx->getParent();
2143 if (Ctx->isFileContext())
2144 Namespaces.insert(Ctx->getPrimaryContext());
2147 // \brief Add the associated classes and namespaces for argument-dependent
2148 // lookup that involves a template argument (C++ [basic.lookup.koenig]p2).
2150 addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
2151 const TemplateArgument &Arg) {
2152 // C++ [basic.lookup.koenig]p2, last bullet:
2154 switch (Arg.getKind()) {
2155 case TemplateArgument::Null:
2158 case TemplateArgument::Type:
2159 // [...] the namespaces and classes associated with the types of the
2160 // template arguments provided for template type parameters (excluding
2161 // template template parameters)
2162 addAssociatedClassesAndNamespaces(Result, Arg.getAsType());
2165 case TemplateArgument::Template:
2166 case TemplateArgument::TemplateExpansion: {
2167 // [...] the namespaces in which any template template arguments are
2168 // defined; and the classes in which any member templates used as
2169 // template template arguments are defined.
2170 TemplateName Template = Arg.getAsTemplateOrTemplatePattern();
2171 if (ClassTemplateDecl *ClassTemplate
2172 = dyn_cast<ClassTemplateDecl>(Template.getAsTemplateDecl())) {
2173 DeclContext *Ctx = ClassTemplate->getDeclContext();
2174 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2175 Result.Classes.insert(EnclosingClass);
2176 // Add the associated namespace for this class.
2177 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2182 case TemplateArgument::Declaration:
2183 case TemplateArgument::Integral:
2184 case TemplateArgument::Expression:
2185 case TemplateArgument::NullPtr:
2186 // [Note: non-type template arguments do not contribute to the set of
2187 // associated namespaces. ]
2190 case TemplateArgument::Pack:
2191 for (const auto &P : Arg.pack_elements())
2192 addAssociatedClassesAndNamespaces(Result, P);
2197 // \brief Add the associated classes and namespaces for
2198 // argument-dependent lookup with an argument of class type
2199 // (C++ [basic.lookup.koenig]p2).
2201 addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
2202 CXXRecordDecl *Class) {
2204 // Just silently ignore anything whose name is __va_list_tag.
2205 if (Class->getDeclName() == Result.S.VAListTagName)
2208 // C++ [basic.lookup.koenig]p2:
2210 // -- If T is a class type (including unions), its associated
2211 // classes are: the class itself; the class of which it is a
2212 // member, if any; and its direct and indirect base
2213 // classes. Its associated namespaces are the namespaces in
2214 // which its associated classes are defined.
2216 // Add the class of which it is a member, if any.
2217 DeclContext *Ctx = Class->getDeclContext();
2218 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2219 Result.Classes.insert(EnclosingClass);
2220 // Add the associated namespace for this class.
2221 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2223 // Add the class itself. If we've already seen this class, we don't
2224 // need to visit base classes.
2226 // FIXME: That's not correct, we may have added this class only because it
2227 // was the enclosing class of another class, and in that case we won't have
2228 // added its base classes yet.
2229 if (!Result.Classes.insert(Class).second)
2232 // -- If T is a template-id, its associated namespaces and classes are
2233 // the namespace in which the template is defined; for member
2234 // templates, the member template's class; the namespaces and classes
2235 // associated with the types of the template arguments provided for
2236 // template type parameters (excluding template template parameters); the
2237 // namespaces in which any template template arguments are defined; and
2238 // the classes in which any member templates used as template template
2239 // arguments are defined. [Note: non-type template arguments do not
2240 // contribute to the set of associated namespaces. ]
2241 if (ClassTemplateSpecializationDecl *Spec
2242 = dyn_cast<ClassTemplateSpecializationDecl>(Class)) {
2243 DeclContext *Ctx = Spec->getSpecializedTemplate()->getDeclContext();
2244 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2245 Result.Classes.insert(EnclosingClass);
2246 // Add the associated namespace for this class.
2247 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2249 const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
2250 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
2251 addAssociatedClassesAndNamespaces(Result, TemplateArgs[I]);
2254 // Only recurse into base classes for complete types.
2255 if (!Class->hasDefinition())
2258 // Add direct and indirect base classes along with their associated
2260 SmallVector<CXXRecordDecl *, 32> Bases;
2261 Bases.push_back(Class);
2262 while (!Bases.empty()) {
2263 // Pop this class off the stack.
2264 Class = Bases.pop_back_val();
2266 // Visit the base classes.
2267 for (const auto &Base : Class->bases()) {
2268 const RecordType *BaseType = Base.getType()->getAs<RecordType>();
2269 // In dependent contexts, we do ADL twice, and the first time around,
2270 // the base type might be a dependent TemplateSpecializationType, or a
2271 // TemplateTypeParmType. If that happens, simply ignore it.
2272 // FIXME: If we want to support export, we probably need to add the
2273 // namespace of the template in a TemplateSpecializationType, or even
2274 // the classes and namespaces of known non-dependent arguments.
2277 CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(BaseType->getDecl());
2278 if (Result.Classes.insert(BaseDecl).second) {
2279 // Find the associated namespace for this base class.
2280 DeclContext *BaseCtx = BaseDecl->getDeclContext();
2281 CollectEnclosingNamespace(Result.Namespaces, BaseCtx);
2283 // Make sure we visit the bases of this base class.
2284 if (BaseDecl->bases_begin() != BaseDecl->bases_end())
2285 Bases.push_back(BaseDecl);
2291 // \brief Add the associated classes and namespaces for
2292 // argument-dependent lookup with an argument of type T
2293 // (C++ [basic.lookup.koenig]p2).
2295 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType Ty) {
2296 // C++ [basic.lookup.koenig]p2:
2298 // For each argument type T in the function call, there is a set
2299 // of zero or more associated namespaces and a set of zero or more
2300 // associated classes to be considered. The sets of namespaces and
2301 // classes is determined entirely by the types of the function
2302 // arguments (and the namespace of any template template
2303 // argument). Typedef names and using-declarations used to specify
2304 // the types do not contribute to this set. The sets of namespaces
2305 // and classes are determined in the following way:
2307 SmallVector<const Type *, 16> Queue;
2308 const Type *T = Ty->getCanonicalTypeInternal().getTypePtr();
2311 switch (T->getTypeClass()) {
2313 #define TYPE(Class, Base)
2314 #define DEPENDENT_TYPE(Class, Base) case Type::Class:
2315 #define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2316 #define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
2317 #define ABSTRACT_TYPE(Class, Base)
2318 #include "clang/AST/TypeNodes.def"
2319 // T is canonical. We can also ignore dependent types because
2320 // we don't need to do ADL at the definition point, but if we
2321 // wanted to implement template export (or if we find some other
2322 // use for associated classes and namespaces...) this would be
2326 // -- If T is a pointer to U or an array of U, its associated
2327 // namespaces and classes are those associated with U.
2329 T = cast<PointerType>(T)->getPointeeType().getTypePtr();
2331 case Type::ConstantArray:
2332 case Type::IncompleteArray:
2333 case Type::VariableArray:
2334 T = cast<ArrayType>(T)->getElementType().getTypePtr();
2337 // -- If T is a fundamental type, its associated sets of
2338 // namespaces and classes are both empty.
2342 // -- If T is a class type (including unions), its associated
2343 // classes are: the class itself; the class of which it is a
2344 // member, if any; and its direct and indirect base
2345 // classes. Its associated namespaces are the namespaces in
2346 // which its associated classes are defined.
2347 case Type::Record: {
2348 Result.S.RequireCompleteType(Result.InstantiationLoc, QualType(T, 0),
2349 /*no diagnostic*/ 0);
2350 CXXRecordDecl *Class
2351 = cast<CXXRecordDecl>(cast<RecordType>(T)->getDecl());
2352 addAssociatedClassesAndNamespaces(Result, Class);
2356 // -- If T is an enumeration type, its associated namespace is
2357 // the namespace in which it is defined. If it is class
2358 // member, its associated class is the member's class; else
2359 // it has no associated class.
2361 EnumDecl *Enum = cast<EnumType>(T)->getDecl();
2363 DeclContext *Ctx = Enum->getDeclContext();
2364 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2365 Result.Classes.insert(EnclosingClass);
2367 // Add the associated namespace for this class.
2368 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2373 // -- If T is a function type, its associated namespaces and
2374 // classes are those associated with the function parameter
2375 // types and those associated with the return type.
2376 case Type::FunctionProto: {
2377 const FunctionProtoType *Proto = cast<FunctionProtoType>(T);
2378 for (const auto &Arg : Proto->param_types())
2379 Queue.push_back(Arg.getTypePtr());
2382 case Type::FunctionNoProto: {
2383 const FunctionType *FnType = cast<FunctionType>(T);
2384 T = FnType->getReturnType().getTypePtr();
2388 // -- If T is a pointer to a member function of a class X, its
2389 // associated namespaces and classes are those associated
2390 // with the function parameter types and return type,
2391 // together with those associated with X.
2393 // -- If T is a pointer to a data member of class X, its
2394 // associated namespaces and classes are those associated
2395 // with the member type together with those associated with
2397 case Type::MemberPointer: {
2398 const MemberPointerType *MemberPtr = cast<MemberPointerType>(T);
2400 // Queue up the class type into which this points.
2401 Queue.push_back(MemberPtr->getClass());
2403 // And directly continue with the pointee type.
2404 T = MemberPtr->getPointeeType().getTypePtr();
2408 // As an extension, treat this like a normal pointer.
2409 case Type::BlockPointer:
2410 T = cast<BlockPointerType>(T)->getPointeeType().getTypePtr();
2413 // References aren't covered by the standard, but that's such an
2414 // obvious defect that we cover them anyway.
2415 case Type::LValueReference:
2416 case Type::RValueReference:
2417 T = cast<ReferenceType>(T)->getPointeeType().getTypePtr();
2420 // These are fundamental types.
2422 case Type::ExtVector:
2426 // Non-deduced auto types only get here for error cases.
2430 // If T is an Objective-C object or interface type, or a pointer to an
2431 // object or interface type, the associated namespace is the global
2433 case Type::ObjCObject:
2434 case Type::ObjCInterface:
2435 case Type::ObjCObjectPointer:
2436 Result.Namespaces.insert(Result.S.Context.getTranslationUnitDecl());
2439 // Atomic types are just wrappers; use the associations of the
2442 T = cast<AtomicType>(T)->getValueType().getTypePtr();
2448 T = Queue.pop_back_val();
2452 /// \brief Find the associated classes and namespaces for
2453 /// argument-dependent lookup for a call with the given set of
2456 /// This routine computes the sets of associated classes and associated
2457 /// namespaces searched by argument-dependent lookup
2458 /// (C++ [basic.lookup.argdep]) for a given set of arguments.
2459 void Sema::FindAssociatedClassesAndNamespaces(
2460 SourceLocation InstantiationLoc, ArrayRef<Expr *> Args,
2461 AssociatedNamespaceSet &AssociatedNamespaces,
2462 AssociatedClassSet &AssociatedClasses) {
2463 AssociatedNamespaces.clear();
2464 AssociatedClasses.clear();
2466 AssociatedLookup Result(*this, InstantiationLoc,
2467 AssociatedNamespaces, AssociatedClasses);
2469 // C++ [basic.lookup.koenig]p2:
2470 // For each argument type T in the function call, there is a set
2471 // of zero or more associated namespaces and a set of zero or more
2472 // associated classes to be considered. The sets of namespaces and
2473 // classes is determined entirely by the types of the function
2474 // arguments (and the namespace of any template template
2476 for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) {
2477 Expr *Arg = Args[ArgIdx];
2479 if (Arg->getType() != Context.OverloadTy) {
2480 addAssociatedClassesAndNamespaces(Result, Arg->getType());
2484 // [...] In addition, if the argument is the name or address of a
2485 // set of overloaded functions and/or function templates, its
2486 // associated classes and namespaces are the union of those
2487 // associated with each of the members of the set: the namespace
2488 // in which the function or function template is defined and the
2489 // classes and namespaces associated with its (non-dependent)
2490 // parameter types and return type.
2491 Arg = Arg->IgnoreParens();
2492 if (UnaryOperator *unaryOp = dyn_cast<UnaryOperator>(Arg))
2493 if (unaryOp->getOpcode() == UO_AddrOf)
2494 Arg = unaryOp->getSubExpr();
2496 UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Arg);
2499 for (const auto *D : ULE->decls()) {
2500 // Look through any using declarations to find the underlying function.
2501 const FunctionDecl *FDecl = D->getUnderlyingDecl()->getAsFunction();
2503 // Add the classes and namespaces associated with the parameter
2504 // types and return type of this function.
2505 addAssociatedClassesAndNamespaces(Result, FDecl->getType());
2510 NamedDecl *Sema::LookupSingleName(Scope *S, DeclarationName Name,
2512 LookupNameKind NameKind,
2513 RedeclarationKind Redecl) {
2514 LookupResult R(*this, Name, Loc, NameKind, Redecl);
2516 return R.getAsSingle<NamedDecl>();
2519 /// \brief Find the protocol with the given name, if any.
2520 ObjCProtocolDecl *Sema::LookupProtocol(IdentifierInfo *II,
2521 SourceLocation IdLoc,
2522 RedeclarationKind Redecl) {
2523 Decl *D = LookupSingleName(TUScope, II, IdLoc,
2524 LookupObjCProtocolName, Redecl);
2525 return cast_or_null<ObjCProtocolDecl>(D);
2528 void Sema::LookupOverloadedOperatorName(OverloadedOperatorKind Op, Scope *S,
2529 QualType T1, QualType T2,
2530 UnresolvedSetImpl &Functions) {
2531 // C++ [over.match.oper]p3:
2532 // -- The set of non-member candidates is the result of the
2533 // unqualified lookup of operator@ in the context of the
2534 // expression according to the usual rules for name lookup in
2535 // unqualified function calls (3.4.2) except that all member
2536 // functions are ignored.
2537 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op);
2538 LookupResult Operators(*this, OpName, SourceLocation(), LookupOperatorName);
2539 LookupName(Operators, S);
2541 assert(!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous");
2542 Functions.append(Operators.begin(), Operators.end());
2545 Sema::SpecialMemberOverloadResult *Sema::LookupSpecialMember(CXXRecordDecl *RD,
2546 CXXSpecialMember SM,
2551 bool VolatileThis) {
2552 assert(CanDeclareSpecialMemberFunction(RD) &&
2553 "doing special member lookup into record that isn't fully complete");
2554 RD = RD->getDefinition();
2555 if (RValueThis || ConstThis || VolatileThis)
2556 assert((SM == CXXCopyAssignment || SM == CXXMoveAssignment) &&
2557 "constructors and destructors always have unqualified lvalue this");
2558 if (ConstArg || VolatileArg)
2559 assert((SM != CXXDefaultConstructor && SM != CXXDestructor) &&
2560 "parameter-less special members can't have qualified arguments");
2562 llvm::FoldingSetNodeID ID;
2565 ID.AddInteger(ConstArg);
2566 ID.AddInteger(VolatileArg);
2567 ID.AddInteger(RValueThis);
2568 ID.AddInteger(ConstThis);
2569 ID.AddInteger(VolatileThis);
2572 SpecialMemberOverloadResult *Result =
2573 SpecialMemberCache.FindNodeOrInsertPos(ID, InsertPoint);
2575 // This was already cached
2579 Result = BumpAlloc.Allocate<SpecialMemberOverloadResult>();
2580 Result = new (Result) SpecialMemberOverloadResult(ID);
2581 SpecialMemberCache.InsertNode(Result, InsertPoint);
2583 if (SM == CXXDestructor) {
2584 if (RD->needsImplicitDestructor())
2585 DeclareImplicitDestructor(RD);
2586 CXXDestructorDecl *DD = RD->getDestructor();
2587 assert(DD && "record without a destructor");
2588 Result->setMethod(DD);
2589 Result->setKind(DD->isDeleted() ?
2590 SpecialMemberOverloadResult::NoMemberOrDeleted :
2591 SpecialMemberOverloadResult::Success);
2595 // Prepare for overload resolution. Here we construct a synthetic argument
2596 // if necessary and make sure that implicit functions are declared.
2597 CanQualType CanTy = Context.getCanonicalType(Context.getTagDeclType(RD));
2598 DeclarationName Name;
2599 Expr *Arg = nullptr;
2602 QualType ArgType = CanTy;
2603 ExprValueKind VK = VK_LValue;
2605 if (SM == CXXDefaultConstructor) {
2606 Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
2608 if (RD->needsImplicitDefaultConstructor())
2609 DeclareImplicitDefaultConstructor(RD);
2611 if (SM == CXXCopyConstructor || SM == CXXMoveConstructor) {
2612 Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
2613 if (RD->needsImplicitCopyConstructor())
2614 DeclareImplicitCopyConstructor(RD);
2615 if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveConstructor())
2616 DeclareImplicitMoveConstructor(RD);
2618 Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
2619 if (RD->needsImplicitCopyAssignment())
2620 DeclareImplicitCopyAssignment(RD);
2621 if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveAssignment())
2622 DeclareImplicitMoveAssignment(RD);
2628 ArgType.addVolatile();
2630 // This isn't /really/ specified by the standard, but it's implied
2631 // we should be working from an RValue in the case of move to ensure
2632 // that we prefer to bind to rvalue references, and an LValue in the
2633 // case of copy to ensure we don't bind to rvalue references.
2634 // Possibly an XValue is actually correct in the case of move, but
2635 // there is no semantic difference for class types in this restricted
2637 if (SM == CXXCopyConstructor || SM == CXXCopyAssignment)
2643 OpaqueValueExpr FakeArg(SourceLocation(), ArgType, VK);
2645 if (SM != CXXDefaultConstructor) {
2650 // Create the object argument
2651 QualType ThisTy = CanTy;
2655 ThisTy.addVolatile();
2656 Expr::Classification Classification =
2657 OpaqueValueExpr(SourceLocation(), ThisTy,
2658 RValueThis ? VK_RValue : VK_LValue).Classify(Context);
2660 // Now we perform lookup on the name we computed earlier and do overload
2661 // resolution. Lookup is only performed directly into the class since there
2662 // will always be a (possibly implicit) declaration to shadow any others.
2663 OverloadCandidateSet OCS(RD->getLocation(), OverloadCandidateSet::CSK_Normal);
2664 DeclContext::lookup_result R = RD->lookup(Name);
2667 // We might have no default constructor because we have a lambda's closure
2668 // type, rather than because there's some other declared constructor.
2669 // Every class has a copy/move constructor, copy/move assignment, and
2671 assert(SM == CXXDefaultConstructor &&
2672 "lookup for a constructor or assignment operator was empty");
2673 Result->setMethod(nullptr);
2674 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
2678 // Copy the candidates as our processing of them may load new declarations
2679 // from an external source and invalidate lookup_result.
2680 SmallVector<NamedDecl *, 8> Candidates(R.begin(), R.end());
2682 for (auto *Cand : Candidates) {
2683 if (Cand->isInvalidDecl())
2686 if (UsingShadowDecl *U = dyn_cast<UsingShadowDecl>(Cand)) {
2687 // FIXME: [namespace.udecl]p15 says that we should only consider a
2688 // using declaration here if it does not match a declaration in the
2689 // derived class. We do not implement this correctly in other cases
2691 Cand = U->getTargetDecl();
2693 if (Cand->isInvalidDecl())
2697 if (CXXMethodDecl *M = dyn_cast<CXXMethodDecl>(Cand)) {
2698 if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
2699 AddMethodCandidate(M, DeclAccessPair::make(M, AS_public), RD, ThisTy,
2700 Classification, llvm::makeArrayRef(&Arg, NumArgs),
2703 AddOverloadCandidate(M, DeclAccessPair::make(M, AS_public),
2704 llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
2705 } else if (FunctionTemplateDecl *Tmpl =
2706 dyn_cast<FunctionTemplateDecl>(Cand)) {
2707 if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
2708 AddMethodTemplateCandidate(Tmpl, DeclAccessPair::make(Tmpl, AS_public),
2709 RD, nullptr, ThisTy, Classification,
2710 llvm::makeArrayRef(&Arg, NumArgs),
2713 AddTemplateOverloadCandidate(Tmpl, DeclAccessPair::make(Tmpl, AS_public),
2714 nullptr, llvm::makeArrayRef(&Arg, NumArgs),
2717 assert(isa<UsingDecl>(Cand) && "illegal Kind of operator = Decl");
2721 OverloadCandidateSet::iterator Best;
2722 switch (OCS.BestViableFunction(*this, SourceLocation(), Best)) {
2724 Result->setMethod(cast<CXXMethodDecl>(Best->Function));
2725 Result->setKind(SpecialMemberOverloadResult::Success);
2729 Result->setMethod(cast<CXXMethodDecl>(Best->Function));
2730 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
2734 Result->setMethod(nullptr);
2735 Result->setKind(SpecialMemberOverloadResult::Ambiguous);
2738 case OR_No_Viable_Function:
2739 Result->setMethod(nullptr);
2740 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
2747 /// \brief Look up the default constructor for the given class.
2748 CXXConstructorDecl *Sema::LookupDefaultConstructor(CXXRecordDecl *Class) {
2749 SpecialMemberOverloadResult *Result =
2750 LookupSpecialMember(Class, CXXDefaultConstructor, false, false, false,
2753 return cast_or_null<CXXConstructorDecl>(Result->getMethod());
2756 /// \brief Look up the copying constructor for the given class.
2757 CXXConstructorDecl *Sema::LookupCopyingConstructor(CXXRecordDecl *Class,
2759 assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
2760 "non-const, non-volatile qualifiers for copy ctor arg");
2761 SpecialMemberOverloadResult *Result =
2762 LookupSpecialMember(Class, CXXCopyConstructor, Quals & Qualifiers::Const,
2763 Quals & Qualifiers::Volatile, false, false, false);
2765 return cast_or_null<CXXConstructorDecl>(Result->getMethod());
2768 /// \brief Look up the moving constructor for the given class.
2769 CXXConstructorDecl *Sema::LookupMovingConstructor(CXXRecordDecl *Class,
2771 SpecialMemberOverloadResult *Result =
2772 LookupSpecialMember(Class, CXXMoveConstructor, Quals & Qualifiers::Const,
2773 Quals & Qualifiers::Volatile, false, false, false);
2775 return cast_or_null<CXXConstructorDecl>(Result->getMethod());
2778 /// \brief Look up the constructors for the given class.
2779 DeclContext::lookup_result Sema::LookupConstructors(CXXRecordDecl *Class) {
2780 // If the implicit constructors have not yet been declared, do so now.
2781 if (CanDeclareSpecialMemberFunction(Class)) {
2782 if (Class->needsImplicitDefaultConstructor())
2783 DeclareImplicitDefaultConstructor(Class);
2784 if (Class->needsImplicitCopyConstructor())
2785 DeclareImplicitCopyConstructor(Class);
2786 if (getLangOpts().CPlusPlus11 && Class->needsImplicitMoveConstructor())
2787 DeclareImplicitMoveConstructor(Class);
2790 CanQualType T = Context.getCanonicalType(Context.getTypeDeclType(Class));
2791 DeclarationName Name = Context.DeclarationNames.getCXXConstructorName(T);
2792 return Class->lookup(Name);
2795 /// \brief Look up the copying assignment operator for the given class.
2796 CXXMethodDecl *Sema::LookupCopyingAssignment(CXXRecordDecl *Class,
2797 unsigned Quals, bool RValueThis,
2798 unsigned ThisQuals) {
2799 assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
2800 "non-const, non-volatile qualifiers for copy assignment arg");
2801 assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
2802 "non-const, non-volatile qualifiers for copy assignment this");
2803 SpecialMemberOverloadResult *Result =
2804 LookupSpecialMember(Class, CXXCopyAssignment, Quals & Qualifiers::Const,
2805 Quals & Qualifiers::Volatile, RValueThis,
2806 ThisQuals & Qualifiers::Const,
2807 ThisQuals & Qualifiers::Volatile);
2809 return Result->getMethod();
2812 /// \brief Look up the moving assignment operator for the given class.
2813 CXXMethodDecl *Sema::LookupMovingAssignment(CXXRecordDecl *Class,
2816 unsigned ThisQuals) {
2817 assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
2818 "non-const, non-volatile qualifiers for copy assignment this");
2819 SpecialMemberOverloadResult *Result =
2820 LookupSpecialMember(Class, CXXMoveAssignment, Quals & Qualifiers::Const,
2821 Quals & Qualifiers::Volatile, RValueThis,
2822 ThisQuals & Qualifiers::Const,
2823 ThisQuals & Qualifiers::Volatile);
2825 return Result->getMethod();
2828 /// \brief Look for the destructor of the given class.
2830 /// During semantic analysis, this routine should be used in lieu of
2831 /// CXXRecordDecl::getDestructor().
2833 /// \returns The destructor for this class.
2834 CXXDestructorDecl *Sema::LookupDestructor(CXXRecordDecl *Class) {
2835 return cast<CXXDestructorDecl>(LookupSpecialMember(Class, CXXDestructor,
2836 false, false, false,
2837 false, false)->getMethod());
2840 /// LookupLiteralOperator - Determine which literal operator should be used for
2841 /// a user-defined literal, per C++11 [lex.ext].
2843 /// Normal overload resolution is not used to select which literal operator to
2844 /// call for a user-defined literal. Look up the provided literal operator name,
2845 /// and filter the results to the appropriate set for the given argument types.
2846 Sema::LiteralOperatorLookupResult
2847 Sema::LookupLiteralOperator(Scope *S, LookupResult &R,
2848 ArrayRef<QualType> ArgTys,
2849 bool AllowRaw, bool AllowTemplate,
2850 bool AllowStringTemplate) {
2852 assert(R.getResultKind() != LookupResult::Ambiguous &&
2853 "literal operator lookup can't be ambiguous");
2855 // Filter the lookup results appropriately.
2856 LookupResult::Filter F = R.makeFilter();
2858 bool FoundRaw = false;
2859 bool FoundTemplate = false;
2860 bool FoundStringTemplate = false;
2861 bool FoundExactMatch = false;
2863 while (F.hasNext()) {
2865 if (UsingShadowDecl *USD = dyn_cast<UsingShadowDecl>(D))
2866 D = USD->getTargetDecl();
2868 // If the declaration we found is invalid, skip it.
2869 if (D->isInvalidDecl()) {
2875 bool IsTemplate = false;
2876 bool IsStringTemplate = false;
2877 bool IsExactMatch = false;
2879 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
2880 if (FD->getNumParams() == 1 &&
2881 FD->getParamDecl(0)->getType()->getAs<PointerType>())
2883 else if (FD->getNumParams() == ArgTys.size()) {
2884 IsExactMatch = true;
2885 for (unsigned ArgIdx = 0; ArgIdx != ArgTys.size(); ++ArgIdx) {
2886 QualType ParamTy = FD->getParamDecl(ArgIdx)->getType();
2887 if (!Context.hasSameUnqualifiedType(ArgTys[ArgIdx], ParamTy)) {
2888 IsExactMatch = false;
2894 if (FunctionTemplateDecl *FD = dyn_cast<FunctionTemplateDecl>(D)) {
2895 TemplateParameterList *Params = FD->getTemplateParameters();
2896 if (Params->size() == 1)
2899 IsStringTemplate = true;
2903 FoundExactMatch = true;
2905 AllowTemplate = false;
2906 AllowStringTemplate = false;
2907 if (FoundRaw || FoundTemplate || FoundStringTemplate) {
2908 // Go through again and remove the raw and template decls we've
2911 FoundRaw = FoundTemplate = FoundStringTemplate = false;
2913 } else if (AllowRaw && IsRaw) {
2915 } else if (AllowTemplate && IsTemplate) {
2916 FoundTemplate = true;
2917 } else if (AllowStringTemplate && IsStringTemplate) {
2918 FoundStringTemplate = true;
2926 // C++11 [lex.ext]p3, p4: If S contains a literal operator with a matching
2927 // parameter type, that is used in preference to a raw literal operator
2928 // or literal operator template.
2929 if (FoundExactMatch)
2932 // C++11 [lex.ext]p3, p4: S shall contain a raw literal operator or a literal
2933 // operator template, but not both.
2934 if (FoundRaw && FoundTemplate) {
2935 Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call) << R.getLookupName();
2936 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
2937 NoteOverloadCandidate((*I)->getUnderlyingDecl()->getAsFunction());
2945 return LOLR_Template;
2947 if (FoundStringTemplate)
2948 return LOLR_StringTemplate;
2950 // Didn't find anything we could use.
2951 Diag(R.getNameLoc(), diag::err_ovl_no_viable_literal_operator)
2952 << R.getLookupName() << (int)ArgTys.size() << ArgTys[0]
2953 << (ArgTys.size() == 2 ? ArgTys[1] : QualType()) << AllowRaw
2954 << (AllowTemplate || AllowStringTemplate);
2958 void ADLResult::insert(NamedDecl *New) {
2959 NamedDecl *&Old = Decls[cast<NamedDecl>(New->getCanonicalDecl())];
2961 // If we haven't yet seen a decl for this key, or the last decl
2962 // was exactly this one, we're done.
2963 if (Old == nullptr || Old == New) {
2968 // Otherwise, decide which is a more recent redeclaration.
2969 FunctionDecl *OldFD = Old->getAsFunction();
2970 FunctionDecl *NewFD = New->getAsFunction();
2972 FunctionDecl *Cursor = NewFD;
2974 Cursor = Cursor->getPreviousDecl();
2976 // If we got to the end without finding OldFD, OldFD is the newer
2977 // declaration; leave things as they are.
2978 if (!Cursor) return;
2980 // If we do find OldFD, then NewFD is newer.
2981 if (Cursor == OldFD) break;
2983 // Otherwise, keep looking.
2989 void Sema::ArgumentDependentLookup(DeclarationName Name, SourceLocation Loc,
2990 ArrayRef<Expr *> Args, ADLResult &Result) {
2991 // Find all of the associated namespaces and classes based on the
2992 // arguments we have.
2993 AssociatedNamespaceSet AssociatedNamespaces;
2994 AssociatedClassSet AssociatedClasses;
2995 FindAssociatedClassesAndNamespaces(Loc, Args,
2996 AssociatedNamespaces,
2999 // C++ [basic.lookup.argdep]p3:
3000 // Let X be the lookup set produced by unqualified lookup (3.4.1)
3001 // and let Y be the lookup set produced by argument dependent
3002 // lookup (defined as follows). If X contains [...] then Y is
3003 // empty. Otherwise Y is the set of declarations found in the
3004 // namespaces associated with the argument types as described
3005 // below. The set of declarations found by the lookup of the name
3006 // is the union of X and Y.
3008 // Here, we compute Y and add its members to the overloaded
3010 for (auto *NS : AssociatedNamespaces) {
3011 // When considering an associated namespace, the lookup is the
3012 // same as the lookup performed when the associated namespace is
3013 // used as a qualifier (3.4.3.2) except that:
3015 // -- Any using-directives in the associated namespace are
3018 // -- Any namespace-scope friend functions declared in
3019 // associated classes are visible within their respective
3020 // namespaces even if they are not visible during an ordinary
3022 DeclContext::lookup_result R = NS->lookup(Name);
3024 // If the only declaration here is an ordinary friend, consider
3025 // it only if it was declared in an associated classes.
3026 if ((D->getIdentifierNamespace() & Decl::IDNS_Ordinary) == 0) {
3027 // If it's neither ordinarily visible nor a friend, we can't find it.
3028 if ((D->getIdentifierNamespace() & Decl::IDNS_OrdinaryFriend) == 0)
3031 bool DeclaredInAssociatedClass = false;
3032 for (Decl *DI = D; DI; DI = DI->getPreviousDecl()) {
3033 DeclContext *LexDC = DI->getLexicalDeclContext();
3034 if (isa<CXXRecordDecl>(LexDC) &&
3035 AssociatedClasses.count(cast<CXXRecordDecl>(LexDC))) {
3036 DeclaredInAssociatedClass = true;
3040 if (!DeclaredInAssociatedClass)
3044 if (isa<UsingShadowDecl>(D))
3045 D = cast<UsingShadowDecl>(D)->getTargetDecl();
3047 if (!isa<FunctionDecl>(D) && !isa<FunctionTemplateDecl>(D))
3050 if (!isVisible(D) && !(D = findAcceptableDecl(*this, D)))
3058 //----------------------------------------------------------------------------
3059 // Search for all visible declarations.
3060 //----------------------------------------------------------------------------
3061 VisibleDeclConsumer::~VisibleDeclConsumer() { }
3063 bool VisibleDeclConsumer::includeHiddenDecls() const { return false; }
3067 class ShadowContextRAII;
3069 class VisibleDeclsRecord {
3071 /// \brief An entry in the shadow map, which is optimized to store a
3072 /// single declaration (the common case) but can also store a list
3073 /// of declarations.
3074 typedef llvm::TinyPtrVector<NamedDecl*> ShadowMapEntry;
3077 /// \brief A mapping from declaration names to the declarations that have
3078 /// this name within a particular scope.
3079 typedef llvm::DenseMap<DeclarationName, ShadowMapEntry> ShadowMap;
3081 /// \brief A list of shadow maps, which is used to model name hiding.
3082 std::list<ShadowMap> ShadowMaps;
3084 /// \brief The declaration contexts we have already visited.
3085 llvm::SmallPtrSet<DeclContext *, 8> VisitedContexts;
3087 friend class ShadowContextRAII;
3090 /// \brief Determine whether we have already visited this context
3091 /// (and, if not, note that we are going to visit that context now).
3092 bool visitedContext(DeclContext *Ctx) {
3093 return !VisitedContexts.insert(Ctx).second;
3096 bool alreadyVisitedContext(DeclContext *Ctx) {
3097 return VisitedContexts.count(Ctx);
3100 /// \brief Determine whether the given declaration is hidden in the
3103 /// \returns the declaration that hides the given declaration, or
3104 /// NULL if no such declaration exists.
3105 NamedDecl *checkHidden(NamedDecl *ND);
3107 /// \brief Add a declaration to the current shadow map.
3108 void add(NamedDecl *ND) {
3109 ShadowMaps.back()[ND->getDeclName()].push_back(ND);
3113 /// \brief RAII object that records when we've entered a shadow context.
3114 class ShadowContextRAII {
3115 VisibleDeclsRecord &Visible;
3117 typedef VisibleDeclsRecord::ShadowMap ShadowMap;
3120 ShadowContextRAII(VisibleDeclsRecord &Visible) : Visible(Visible) {
3121 Visible.ShadowMaps.emplace_back();
3124 ~ShadowContextRAII() {
3125 Visible.ShadowMaps.pop_back();
3129 } // end anonymous namespace
3131 NamedDecl *VisibleDeclsRecord::checkHidden(NamedDecl *ND) {
3132 // Look through using declarations.
3133 ND = ND->getUnderlyingDecl();
3135 unsigned IDNS = ND->getIdentifierNamespace();
3136 std::list<ShadowMap>::reverse_iterator SM = ShadowMaps.rbegin();
3137 for (std::list<ShadowMap>::reverse_iterator SMEnd = ShadowMaps.rend();
3138 SM != SMEnd; ++SM) {
3139 ShadowMap::iterator Pos = SM->find(ND->getDeclName());
3140 if (Pos == SM->end())
3143 for (auto *D : Pos->second) {
3144 // A tag declaration does not hide a non-tag declaration.
3145 if (D->hasTagIdentifierNamespace() &&
3146 (IDNS & (Decl::IDNS_Member | Decl::IDNS_Ordinary |
3147 Decl::IDNS_ObjCProtocol)))
3150 // Protocols are in distinct namespaces from everything else.
3151 if (((D->getIdentifierNamespace() & Decl::IDNS_ObjCProtocol)
3152 || (IDNS & Decl::IDNS_ObjCProtocol)) &&
3153 D->getIdentifierNamespace() != IDNS)
3156 // Functions and function templates in the same scope overload
3157 // rather than hide. FIXME: Look for hiding based on function
3159 if (D->getUnderlyingDecl()->isFunctionOrFunctionTemplate() &&
3160 ND->getUnderlyingDecl()->isFunctionOrFunctionTemplate() &&
3161 SM == ShadowMaps.rbegin())
3164 // We've found a declaration that hides this one.
3172 static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
3173 bool QualifiedNameLookup,
3175 VisibleDeclConsumer &Consumer,
3176 VisibleDeclsRecord &Visited) {
3180 // Make sure we don't visit the same context twice.
3181 if (Visited.visitedContext(Ctx->getPrimaryContext()))
3184 // Outside C++, lookup results for the TU live on identifiers.
3185 if (isa<TranslationUnitDecl>(Ctx) &&
3186 !Result.getSema().getLangOpts().CPlusPlus) {
3187 auto &S = Result.getSema();
3188 auto &Idents = S.Context.Idents;
3190 // Ensure all external identifiers are in the identifier table.
3191 if (IdentifierInfoLookup *External = Idents.getExternalIdentifierLookup()) {
3192 std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
3193 for (StringRef Name = Iter->Next(); !Name.empty(); Name = Iter->Next())
3197 // Walk all lookup results in the TU for each identifier.
3198 for (const auto &Ident : Idents) {
3199 for (auto I = S.IdResolver.begin(Ident.getValue()),
3200 E = S.IdResolver.end();
3202 if (S.IdResolver.isDeclInScope(*I, Ctx)) {
3203 if (NamedDecl *ND = Result.getAcceptableDecl(*I)) {
3204 Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
3214 if (CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(Ctx))
3215 Result.getSema().ForceDeclarationOfImplicitMembers(Class);
3217 // Enumerate all of the results in this context.
3218 for (DeclContextLookupResult R : Ctx->lookups()) {
3220 if (auto *ND = Result.getAcceptableDecl(D)) {
3221 Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
3227 // Traverse using directives for qualified name lookup.
3228 if (QualifiedNameLookup) {
3229 ShadowContextRAII Shadow(Visited);
3230 for (auto I : Ctx->using_directives()) {
3231 LookupVisibleDecls(I->getNominatedNamespace(), Result,
3232 QualifiedNameLookup, InBaseClass, Consumer, Visited);
3236 // Traverse the contexts of inherited C++ classes.
3237 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) {
3238 if (!Record->hasDefinition())
3241 for (const auto &B : Record->bases()) {
3242 QualType BaseType = B.getType();
3244 // Don't look into dependent bases, because name lookup can't look
3246 if (BaseType->isDependentType())
3249 const RecordType *Record = BaseType->getAs<RecordType>();
3253 // FIXME: It would be nice to be able to determine whether referencing
3254 // a particular member would be ambiguous. For example, given
3256 // struct A { int member; };
3257 // struct B { int member; };
3258 // struct C : A, B { };
3260 // void f(C *c) { c->### }
3262 // accessing 'member' would result in an ambiguity. However, we
3263 // could be smart enough to qualify the member with the base
3272 // Find results in this base class (and its bases).
3273 ShadowContextRAII Shadow(Visited);
3274 LookupVisibleDecls(Record->getDecl(), Result, QualifiedNameLookup,
3275 true, Consumer, Visited);
3279 // Traverse the contexts of Objective-C classes.
3280 if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>(Ctx)) {
3281 // Traverse categories.
3282 for (auto *Cat : IFace->visible_categories()) {
3283 ShadowContextRAII Shadow(Visited);
3284 LookupVisibleDecls(Cat, Result, QualifiedNameLookup, false,
3288 // Traverse protocols.
3289 for (auto *I : IFace->all_referenced_protocols()) {
3290 ShadowContextRAII Shadow(Visited);
3291 LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3295 // Traverse the superclass.
3296 if (IFace->getSuperClass()) {
3297 ShadowContextRAII Shadow(Visited);
3298 LookupVisibleDecls(IFace->getSuperClass(), Result, QualifiedNameLookup,
3299 true, Consumer, Visited);
3302 // If there is an implementation, traverse it. We do this to find
3303 // synthesized ivars.
3304 if (IFace->getImplementation()) {
3305 ShadowContextRAII Shadow(Visited);
3306 LookupVisibleDecls(IFace->getImplementation(), Result,
3307 QualifiedNameLookup, InBaseClass, Consumer, Visited);
3309 } else if (ObjCProtocolDecl *Protocol = dyn_cast<ObjCProtocolDecl>(Ctx)) {
3310 for (auto *I : Protocol->protocols()) {
3311 ShadowContextRAII Shadow(Visited);
3312 LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3315 } else if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(Ctx)) {
3316 for (auto *I : Category->protocols()) {
3317 ShadowContextRAII Shadow(Visited);
3318 LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3322 // If there is an implementation, traverse it.
3323 if (Category->getImplementation()) {
3324 ShadowContextRAII Shadow(Visited);
3325 LookupVisibleDecls(Category->getImplementation(), Result,
3326 QualifiedNameLookup, true, Consumer, Visited);
3331 static void LookupVisibleDecls(Scope *S, LookupResult &Result,
3332 UnqualUsingDirectiveSet &UDirs,
3333 VisibleDeclConsumer &Consumer,
3334 VisibleDeclsRecord &Visited) {
3338 if (!S->getEntity() ||
3340 !Visited.alreadyVisitedContext(S->getEntity())) ||
3341 (S->getEntity())->isFunctionOrMethod()) {
3342 FindLocalExternScope FindLocals(Result);
3343 // Walk through the declarations in this Scope.
3344 for (auto *D : S->decls()) {
3345 if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
3346 if ((ND = Result.getAcceptableDecl(ND))) {
3347 Consumer.FoundDecl(ND, Visited.checkHidden(ND), nullptr, false);
3353 // FIXME: C++ [temp.local]p8
3354 DeclContext *Entity = nullptr;
3355 if (S->getEntity()) {
3356 // Look into this scope's declaration context, along with any of its
3357 // parent lookup contexts (e.g., enclosing classes), up to the point
3358 // where we hit the context stored in the next outer scope.
3359 Entity = S->getEntity();
3360 DeclContext *OuterCtx = findOuterContext(S).first; // FIXME
3362 for (DeclContext *Ctx = Entity; Ctx && !Ctx->Equals(OuterCtx);
3363 Ctx = Ctx->getLookupParent()) {
3364 if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
3365 if (Method->isInstanceMethod()) {
3366 // For instance methods, look for ivars in the method's interface.
3367 LookupResult IvarResult(Result.getSema(), Result.getLookupName(),
3368 Result.getNameLoc(), Sema::LookupMemberName);
3369 if (ObjCInterfaceDecl *IFace = Method->getClassInterface()) {
3370 LookupVisibleDecls(IFace, IvarResult, /*QualifiedNameLookup=*/false,
3371 /*InBaseClass=*/false, Consumer, Visited);
3375 // We've already performed all of the name lookup that we need
3376 // to for Objective-C methods; the next context will be the
3381 if (Ctx->isFunctionOrMethod())
3384 LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/false,
3385 /*InBaseClass=*/false, Consumer, Visited);
3387 } else if (!S->getParent()) {
3388 // Look into the translation unit scope. We walk through the translation
3389 // unit's declaration context, because the Scope itself won't have all of
3390 // the declarations if we loaded a precompiled header.
3391 // FIXME: We would like the translation unit's Scope object to point to the
3392 // translation unit, so we don't need this special "if" branch. However,
3393 // doing so would force the normal C++ name-lookup code to look into the
3394 // translation unit decl when the IdentifierInfo chains would suffice.
3395 // Once we fix that problem (which is part of a more general "don't look
3396 // in DeclContexts unless we have to" optimization), we can eliminate this.
3397 Entity = Result.getSema().Context.getTranslationUnitDecl();
3398 LookupVisibleDecls(Entity, Result, /*QualifiedNameLookup=*/false,
3399 /*InBaseClass=*/false, Consumer, Visited);
3403 // Lookup visible declarations in any namespaces found by using
3405 for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(Entity))
3406 LookupVisibleDecls(const_cast<DeclContext *>(UUE.getNominatedNamespace()),
3407 Result, /*QualifiedNameLookup=*/false,
3408 /*InBaseClass=*/false, Consumer, Visited);
3411 // Lookup names in the parent scope.
3412 ShadowContextRAII Shadow(Visited);
3413 LookupVisibleDecls(S->getParent(), Result, UDirs, Consumer, Visited);
3416 void Sema::LookupVisibleDecls(Scope *S, LookupNameKind Kind,
3417 VisibleDeclConsumer &Consumer,
3418 bool IncludeGlobalScope) {
3419 // Determine the set of using directives available during
3420 // unqualified name lookup.
3422 UnqualUsingDirectiveSet UDirs;
3423 if (getLangOpts().CPlusPlus) {
3424 // Find the first namespace or translation-unit scope.
3425 while (S && !isNamespaceOrTranslationUnitScope(S))
3428 UDirs.visitScopeChain(Initial, S);
3432 // Look for visible declarations.
3433 LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
3434 Result.setAllowHidden(Consumer.includeHiddenDecls());
3435 VisibleDeclsRecord Visited;
3436 if (!IncludeGlobalScope)
3437 Visited.visitedContext(Context.getTranslationUnitDecl());
3438 ShadowContextRAII Shadow(Visited);
3439 ::LookupVisibleDecls(Initial, Result, UDirs, Consumer, Visited);
3442 void Sema::LookupVisibleDecls(DeclContext *Ctx, LookupNameKind Kind,
3443 VisibleDeclConsumer &Consumer,
3444 bool IncludeGlobalScope) {
3445 LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
3446 Result.setAllowHidden(Consumer.includeHiddenDecls());
3447 VisibleDeclsRecord Visited;
3448 if (!IncludeGlobalScope)
3449 Visited.visitedContext(Context.getTranslationUnitDecl());
3450 ShadowContextRAII Shadow(Visited);
3451 ::LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/true,
3452 /*InBaseClass=*/false, Consumer, Visited);
3455 /// LookupOrCreateLabel - Do a name lookup of a label with the specified name.
3456 /// If GnuLabelLoc is a valid source location, then this is a definition
3457 /// of an __label__ label name, otherwise it is a normal label definition
3459 LabelDecl *Sema::LookupOrCreateLabel(IdentifierInfo *II, SourceLocation Loc,
3460 SourceLocation GnuLabelLoc) {
3461 // Do a lookup to see if we have a label with this name already.
3462 NamedDecl *Res = nullptr;
3464 if (GnuLabelLoc.isValid()) {
3465 // Local label definitions always shadow existing labels.
3466 Res = LabelDecl::Create(Context, CurContext, Loc, II, GnuLabelLoc);
3467 Scope *S = CurScope;
3468 PushOnScopeChains(Res, S, true);
3469 return cast<LabelDecl>(Res);
3472 // Not a GNU local label.
3473 Res = LookupSingleName(CurScope, II, Loc, LookupLabel, NotForRedeclaration);
3474 // If we found a label, check to see if it is in the same context as us.
3475 // When in a Block, we don't want to reuse a label in an enclosing function.
3476 if (Res && Res->getDeclContext() != CurContext)
3479 // If not forward referenced or defined already, create the backing decl.
3480 Res = LabelDecl::Create(Context, CurContext, Loc, II);
3481 Scope *S = CurScope->getFnParent();
3482 assert(S && "Not in a function?");
3483 PushOnScopeChains(Res, S, true);
3485 return cast<LabelDecl>(Res);
3488 //===----------------------------------------------------------------------===//
3490 //===----------------------------------------------------------------------===//
3492 static bool isCandidateViable(CorrectionCandidateCallback &CCC,
3493 TypoCorrection &Candidate) {
3494 Candidate.setCallbackDistance(CCC.RankCandidate(Candidate));
3495 return Candidate.getEditDistance(false) != TypoCorrection::InvalidDistance;
3498 static void LookupPotentialTypoResult(Sema &SemaRef,
3500 IdentifierInfo *Name,
3501 Scope *S, CXXScopeSpec *SS,
3502 DeclContext *MemberContext,
3503 bool EnteringContext,
3504 bool isObjCIvarLookup,
3507 /// \brief Check whether the declarations found for a typo correction are
3508 /// visible, and if none of them are, convert the correction to an 'import
3509 /// a module' correction.
3510 static void checkCorrectionVisibility(Sema &SemaRef, TypoCorrection &TC) {
3511 if (TC.begin() == TC.end())
3514 TypoCorrection::decl_iterator DI = TC.begin(), DE = TC.end();
3516 for (/**/; DI != DE; ++DI)
3517 if (!LookupResult::isVisible(SemaRef, *DI))
3519 // Nothing to do if all decls are visible.
3523 llvm::SmallVector<NamedDecl*, 4> NewDecls(TC.begin(), DI);
3524 bool AnyVisibleDecls = !NewDecls.empty();
3526 for (/**/; DI != DE; ++DI) {
3527 NamedDecl *VisibleDecl = *DI;
3528 if (!LookupResult::isVisible(SemaRef, *DI))
3529 VisibleDecl = findAcceptableDecl(SemaRef, *DI);
3532 if (!AnyVisibleDecls) {
3533 // Found a visible decl, discard all hidden ones.
3534 AnyVisibleDecls = true;
3537 NewDecls.push_back(VisibleDecl);
3538 } else if (!AnyVisibleDecls && !(*DI)->isModulePrivate())
3539 NewDecls.push_back(*DI);
3542 if (NewDecls.empty())
3543 TC = TypoCorrection();
3545 TC.setCorrectionDecls(NewDecls);
3546 TC.setRequiresImport(!AnyVisibleDecls);
3550 // Fill the supplied vector with the IdentifierInfo pointers for each piece of
3551 // the given NestedNameSpecifier (i.e. given a NestedNameSpecifier "foo::bar::",
3552 // fill the vector with the IdentifierInfo pointers for "foo" and "bar").
3553 static void getNestedNameSpecifierIdentifiers(
3554 NestedNameSpecifier *NNS,
3555 SmallVectorImpl<const IdentifierInfo*> &Identifiers) {
3556 if (NestedNameSpecifier *Prefix = NNS->getPrefix())
3557 getNestedNameSpecifierIdentifiers(Prefix, Identifiers);
3559 Identifiers.clear();
3561 const IdentifierInfo *II = nullptr;
3563 switch (NNS->getKind()) {
3564 case NestedNameSpecifier::Identifier:
3565 II = NNS->getAsIdentifier();
3568 case NestedNameSpecifier::Namespace:
3569 if (NNS->getAsNamespace()->isAnonymousNamespace())
3571 II = NNS->getAsNamespace()->getIdentifier();
3574 case NestedNameSpecifier::NamespaceAlias:
3575 II = NNS->getAsNamespaceAlias()->getIdentifier();
3578 case NestedNameSpecifier::TypeSpecWithTemplate:
3579 case NestedNameSpecifier::TypeSpec:
3580 II = QualType(NNS->getAsType(), 0).getBaseTypeIdentifier();
3583 case NestedNameSpecifier::Global:
3584 case NestedNameSpecifier::Super:
3589 Identifiers.push_back(II);
3592 void TypoCorrectionConsumer::FoundDecl(NamedDecl *ND, NamedDecl *Hiding,
3593 DeclContext *Ctx, bool InBaseClass) {
3594 // Don't consider hidden names for typo correction.
3598 // Only consider entities with identifiers for names, ignoring
3599 // special names (constructors, overloaded operators, selectors,
3601 IdentifierInfo *Name = ND->getIdentifier();
3605 // Only consider visible declarations and declarations from modules with
3606 // names that exactly match.
3607 if (!LookupResult::isVisible(SemaRef, ND) && Name != Typo &&
3608 !findAcceptableDecl(SemaRef, ND))
3611 FoundName(Name->getName());
3614 void TypoCorrectionConsumer::FoundName(StringRef Name) {
3615 // Compute the edit distance between the typo and the name of this
3616 // entity, and add the identifier to the list of results.
3617 addName(Name, nullptr);
3620 void TypoCorrectionConsumer::addKeywordResult(StringRef Keyword) {
3621 // Compute the edit distance between the typo and this keyword,
3622 // and add the keyword to the list of results.
3623 addName(Keyword, nullptr, nullptr, true);
3626 void TypoCorrectionConsumer::addName(StringRef Name, NamedDecl *ND,
3627 NestedNameSpecifier *NNS, bool isKeyword) {
3628 // Use a simple length-based heuristic to determine the minimum possible
3629 // edit distance. If the minimum isn't good enough, bail out early.
3630 StringRef TypoStr = Typo->getName();
3631 unsigned MinED = abs((int)Name.size() - (int)TypoStr.size());
3632 if (MinED && TypoStr.size() / MinED < 3)
3635 // Compute an upper bound on the allowable edit distance, so that the
3636 // edit-distance algorithm can short-circuit.
3637 unsigned UpperBound = (TypoStr.size() + 2) / 3 + 1;
3638 unsigned ED = TypoStr.edit_distance(Name, true, UpperBound);
3639 if (ED >= UpperBound) return;
3641 TypoCorrection TC(&SemaRef.Context.Idents.get(Name), ND, NNS, ED);
3642 if (isKeyword) TC.makeKeyword();
3643 TC.setCorrectionRange(nullptr, Result.getLookupNameInfo());
3647 static const unsigned MaxTypoDistanceResultSets = 5;
3649 void TypoCorrectionConsumer::addCorrection(TypoCorrection Correction) {
3650 StringRef TypoStr = Typo->getName();
3651 StringRef Name = Correction.getCorrectionAsIdentifierInfo()->getName();
3653 // For very short typos, ignore potential corrections that have a different
3654 // base identifier from the typo or which have a normalized edit distance
3655 // longer than the typo itself.
3656 if (TypoStr.size() < 3 &&
3657 (Name != TypoStr || Correction.getEditDistance(true) > TypoStr.size()))
3660 // If the correction is resolved but is not viable, ignore it.
3661 if (Correction.isResolved()) {
3662 checkCorrectionVisibility(SemaRef, Correction);
3663 if (!Correction || !isCandidateViable(*CorrectionValidator, Correction))
3667 TypoResultList &CList =
3668 CorrectionResults[Correction.getEditDistance(false)][Name];
3670 if (!CList.empty() && !CList.back().isResolved())
3672 if (NamedDecl *NewND = Correction.getCorrectionDecl()) {
3673 std::string CorrectionStr = Correction.getAsString(SemaRef.getLangOpts());
3674 for (TypoResultList::iterator RI = CList.begin(), RIEnd = CList.end();
3675 RI != RIEnd; ++RI) {
3676 // If the Correction refers to a decl already in the result list,
3677 // replace the existing result if the string representation of Correction
3678 // comes before the current result alphabetically, then stop as there is
3679 // nothing more to be done to add Correction to the candidate set.
3680 if (RI->getCorrectionDecl() == NewND) {
3681 if (CorrectionStr < RI->getAsString(SemaRef.getLangOpts()))
3687 if (CList.empty() || Correction.isResolved())
3688 CList.push_back(Correction);
3690 while (CorrectionResults.size() > MaxTypoDistanceResultSets)
3691 CorrectionResults.erase(std::prev(CorrectionResults.end()));
3694 void TypoCorrectionConsumer::addNamespaces(
3695 const llvm::MapVector<NamespaceDecl *, bool> &KnownNamespaces) {
3696 SearchNamespaces = true;
3698 for (auto KNPair : KnownNamespaces)
3699 Namespaces.addNameSpecifier(KNPair.first);
3701 bool SSIsTemplate = false;
3702 if (NestedNameSpecifier *NNS =
3703 (SS && SS->isValid()) ? SS->getScopeRep() : nullptr) {
3704 if (const Type *T = NNS->getAsType())
3705 SSIsTemplate = T->getTypeClass() == Type::TemplateSpecialization;
3707 for (const auto *TI : SemaRef.getASTContext().types()) {
3708 if (CXXRecordDecl *CD = TI->getAsCXXRecordDecl()) {
3709 CD = CD->getCanonicalDecl();
3710 if (!CD->isDependentType() && !CD->isAnonymousStructOrUnion() &&
3711 !CD->isUnion() && CD->getIdentifier() &&
3712 (SSIsTemplate || !isa<ClassTemplateSpecializationDecl>(CD)) &&
3713 (CD->isBeingDefined() || CD->isCompleteDefinition()))
3714 Namespaces.addNameSpecifier(CD);
3719 const TypoCorrection &TypoCorrectionConsumer::getNextCorrection() {
3720 if (++CurrentTCIndex < ValidatedCorrections.size())
3721 return ValidatedCorrections[CurrentTCIndex];
3723 CurrentTCIndex = ValidatedCorrections.size();
3724 while (!CorrectionResults.empty()) {
3725 auto DI = CorrectionResults.begin();
3726 if (DI->second.empty()) {
3727 CorrectionResults.erase(DI);
3731 auto RI = DI->second.begin();
3732 if (RI->second.empty()) {
3733 DI->second.erase(RI);
3734 performQualifiedLookups();
3738 TypoCorrection TC = RI->second.pop_back_val();
3739 if (TC.isResolved() || TC.requiresImport() || resolveCorrection(TC)) {
3740 ValidatedCorrections.push_back(TC);
3741 return ValidatedCorrections[CurrentTCIndex];
3744 return ValidatedCorrections[0]; // The empty correction.
3747 bool TypoCorrectionConsumer::resolveCorrection(TypoCorrection &Candidate) {
3748 IdentifierInfo *Name = Candidate.getCorrectionAsIdentifierInfo();
3749 DeclContext *TempMemberContext = MemberContext;
3750 CXXScopeSpec *TempSS = SS.get();
3752 LookupPotentialTypoResult(SemaRef, Result, Name, S, TempSS, TempMemberContext,
3754 CorrectionValidator->IsObjCIvarLookup,
3755 Name == Typo && !Candidate.WillReplaceSpecifier());
3756 switch (Result.getResultKind()) {
3757 case LookupResult::NotFound:
3758 case LookupResult::NotFoundInCurrentInstantiation:
3759 case LookupResult::FoundUnresolvedValue:
3761 // Immediately retry the lookup without the given CXXScopeSpec
3763 Candidate.WillReplaceSpecifier(true);
3766 if (TempMemberContext) {
3769 TempMemberContext = nullptr;
3772 if (SearchNamespaces)
3773 QualifiedResults.push_back(Candidate);
3776 case LookupResult::Ambiguous:
3777 // We don't deal with ambiguities.
3780 case LookupResult::Found:
3781 case LookupResult::FoundOverloaded:
3782 // Store all of the Decls for overloaded symbols
3783 for (auto *TRD : Result)
3784 Candidate.addCorrectionDecl(TRD);
3785 checkCorrectionVisibility(SemaRef, Candidate);
3786 if (!isCandidateViable(*CorrectionValidator, Candidate)) {
3787 if (SearchNamespaces)
3788 QualifiedResults.push_back(Candidate);
3791 Candidate.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
3797 void TypoCorrectionConsumer::performQualifiedLookups() {
3798 unsigned TypoLen = Typo->getName().size();
3799 for (auto QR : QualifiedResults) {
3800 for (auto NSI : Namespaces) {
3801 DeclContext *Ctx = NSI.DeclCtx;
3802 const Type *NSType = NSI.NameSpecifier->getAsType();
3804 // If the current NestedNameSpecifier refers to a class and the
3805 // current correction candidate is the name of that class, then skip
3806 // it as it is unlikely a qualified version of the class' constructor
3807 // is an appropriate correction.
3808 if (CXXRecordDecl *NSDecl = NSType ? NSType->getAsCXXRecordDecl() : 0) {
3809 if (NSDecl->getIdentifier() == QR.getCorrectionAsIdentifierInfo())
3813 TypoCorrection TC(QR);
3814 TC.ClearCorrectionDecls();
3815 TC.setCorrectionSpecifier(NSI.NameSpecifier);
3816 TC.setQualifierDistance(NSI.EditDistance);
3817 TC.setCallbackDistance(0); // Reset the callback distance
3819 // If the current correction candidate and namespace combination are
3820 // too far away from the original typo based on the normalized edit
3821 // distance, then skip performing a qualified name lookup.
3822 unsigned TmpED = TC.getEditDistance(true);
3823 if (QR.getCorrectionAsIdentifierInfo() != Typo && TmpED &&
3824 TypoLen / TmpED < 3)
3828 Result.setLookupName(QR.getCorrectionAsIdentifierInfo());
3829 if (!SemaRef.LookupQualifiedName(Result, Ctx))
3832 // Any corrections added below will be validated in subsequent
3833 // iterations of the main while() loop over the Consumer's contents.
3834 switch (Result.getResultKind()) {
3835 case LookupResult::Found:
3836 case LookupResult::FoundOverloaded: {
3837 if (SS && SS->isValid()) {
3838 std::string NewQualified = TC.getAsString(SemaRef.getLangOpts());
3839 std::string OldQualified;
3840 llvm::raw_string_ostream OldOStream(OldQualified);
3841 SS->getScopeRep()->print(OldOStream, SemaRef.getPrintingPolicy());
3842 OldOStream << Typo->getName();
3843 // If correction candidate would be an identical written qualified
3844 // identifer, then the existing CXXScopeSpec probably included a
3845 // typedef that didn't get accounted for properly.
3846 if (OldOStream.str() == NewQualified)
3849 for (LookupResult::iterator TRD = Result.begin(), TRDEnd = Result.end();
3850 TRD != TRDEnd; ++TRD) {
3851 if (SemaRef.CheckMemberAccess(TC.getCorrectionRange().getBegin(),
3852 NSType ? NSType->getAsCXXRecordDecl()
3854 TRD.getPair()) == Sema::AR_accessible)
3855 TC.addCorrectionDecl(*TRD);
3857 if (TC.isResolved()) {
3858 TC.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
3863 case LookupResult::NotFound:
3864 case LookupResult::NotFoundInCurrentInstantiation:
3865 case LookupResult::Ambiguous:
3866 case LookupResult::FoundUnresolvedValue:
3871 QualifiedResults.clear();
3874 TypoCorrectionConsumer::NamespaceSpecifierSet::NamespaceSpecifierSet(
3875 ASTContext &Context, DeclContext *CurContext, CXXScopeSpec *CurScopeSpec)
3876 : Context(Context), CurContextChain(buildContextChain(CurContext)) {
3877 if (NestedNameSpecifier *NNS =
3878 CurScopeSpec ? CurScopeSpec->getScopeRep() : nullptr) {
3879 llvm::raw_string_ostream SpecifierOStream(CurNameSpecifier);
3880 NNS->print(SpecifierOStream, Context.getPrintingPolicy());
3882 getNestedNameSpecifierIdentifiers(NNS, CurNameSpecifierIdentifiers);
3884 // Build the list of identifiers that would be used for an absolute
3885 // (from the global context) NestedNameSpecifier referring to the current
3887 for (DeclContextList::reverse_iterator C = CurContextChain.rbegin(),
3888 CEnd = CurContextChain.rend();
3890 if (NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(*C))
3891 CurContextIdentifiers.push_back(ND->getIdentifier());
3894 // Add the global context as a NestedNameSpecifier
3895 SpecifierInfo SI = {cast<DeclContext>(Context.getTranslationUnitDecl()),
3896 NestedNameSpecifier::GlobalSpecifier(Context), 1};
3897 DistanceMap[1].push_back(SI);
3900 auto TypoCorrectionConsumer::NamespaceSpecifierSet::buildContextChain(
3901 DeclContext *Start) -> DeclContextList {
3902 assert(Start && "Building a context chain from a null context");
3903 DeclContextList Chain;
3904 for (DeclContext *DC = Start->getPrimaryContext(); DC != nullptr;
3905 DC = DC->getLookupParent()) {
3906 NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(DC);
3907 if (!DC->isInlineNamespace() && !DC->isTransparentContext() &&
3908 !(ND && ND->isAnonymousNamespace()))
3909 Chain.push_back(DC->getPrimaryContext());
3915 TypoCorrectionConsumer::NamespaceSpecifierSet::buildNestedNameSpecifier(
3916 DeclContextList &DeclChain, NestedNameSpecifier *&NNS) {
3917 unsigned NumSpecifiers = 0;
3918 for (DeclContextList::reverse_iterator C = DeclChain.rbegin(),
3919 CEnd = DeclChain.rend();
3921 if (NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(*C)) {
3922 NNS = NestedNameSpecifier::Create(Context, NNS, ND);
3924 } else if (RecordDecl *RD = dyn_cast_or_null<RecordDecl>(*C)) {
3925 NNS = NestedNameSpecifier::Create(Context, NNS, RD->isTemplateDecl(),
3926 RD->getTypeForDecl());
3930 return NumSpecifiers;
3933 void TypoCorrectionConsumer::NamespaceSpecifierSet::addNameSpecifier(
3935 NestedNameSpecifier *NNS = nullptr;
3936 unsigned NumSpecifiers = 0;
3937 DeclContextList NamespaceDeclChain(buildContextChain(Ctx));
3938 DeclContextList FullNamespaceDeclChain(NamespaceDeclChain);
3940 // Eliminate common elements from the two DeclContext chains.
3941 for (DeclContextList::reverse_iterator C = CurContextChain.rbegin(),
3942 CEnd = CurContextChain.rend();
3943 C != CEnd && !NamespaceDeclChain.empty() &&
3944 NamespaceDeclChain.back() == *C; ++C) {
3945 NamespaceDeclChain.pop_back();
3948 // Build the NestedNameSpecifier from what is left of the NamespaceDeclChain
3949 NumSpecifiers = buildNestedNameSpecifier(NamespaceDeclChain, NNS);
3951 // Add an explicit leading '::' specifier if needed.
3952 if (NamespaceDeclChain.empty()) {
3953 // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
3954 NNS = NestedNameSpecifier::GlobalSpecifier(Context);
3956 buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
3957 } else if (NamedDecl *ND =
3958 dyn_cast_or_null<NamedDecl>(NamespaceDeclChain.back())) {
3959 IdentifierInfo *Name = ND->getIdentifier();
3960 bool SameNameSpecifier = false;
3961 if (std::find(CurNameSpecifierIdentifiers.begin(),
3962 CurNameSpecifierIdentifiers.end(),
3963 Name) != CurNameSpecifierIdentifiers.end()) {
3964 std::string NewNameSpecifier;
3965 llvm::raw_string_ostream SpecifierOStream(NewNameSpecifier);
3966 SmallVector<const IdentifierInfo *, 4> NewNameSpecifierIdentifiers;
3967 getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
3968 NNS->print(SpecifierOStream, Context.getPrintingPolicy());
3969 SpecifierOStream.flush();
3970 SameNameSpecifier = NewNameSpecifier == CurNameSpecifier;
3972 if (SameNameSpecifier ||
3973 std::find(CurContextIdentifiers.begin(), CurContextIdentifiers.end(),
3974 Name) != CurContextIdentifiers.end()) {
3975 // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
3976 NNS = NestedNameSpecifier::GlobalSpecifier(Context);
3978 buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
3982 // If the built NestedNameSpecifier would be replacing an existing
3983 // NestedNameSpecifier, use the number of component identifiers that
3984 // would need to be changed as the edit distance instead of the number
3985 // of components in the built NestedNameSpecifier.
3986 if (NNS && !CurNameSpecifierIdentifiers.empty()) {
3987 SmallVector<const IdentifierInfo*, 4> NewNameSpecifierIdentifiers;
3988 getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
3989 NumSpecifiers = llvm::ComputeEditDistance(
3990 llvm::makeArrayRef(CurNameSpecifierIdentifiers),
3991 llvm::makeArrayRef(NewNameSpecifierIdentifiers));
3994 SpecifierInfo SI = {Ctx, NNS, NumSpecifiers};
3995 DistanceMap[NumSpecifiers].push_back(SI);
3998 /// \brief Perform name lookup for a possible result for typo correction.
3999 static void LookupPotentialTypoResult(Sema &SemaRef,
4001 IdentifierInfo *Name,
4002 Scope *S, CXXScopeSpec *SS,
4003 DeclContext *MemberContext,
4004 bool EnteringContext,
4005 bool isObjCIvarLookup,
4007 Res.suppressDiagnostics();
4009 Res.setLookupName(Name);
4010 Res.setAllowHidden(FindHidden);
4011 if (MemberContext) {
4012 if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(MemberContext)) {
4013 if (isObjCIvarLookup) {
4014 if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(Name)) {
4021 if (ObjCPropertyDecl *Prop = Class->FindPropertyDeclaration(Name)) {
4028 SemaRef.LookupQualifiedName(Res, MemberContext);
4032 SemaRef.LookupParsedName(Res, S, SS, /*AllowBuiltinCreation=*/false,
4035 // Fake ivar lookup; this should really be part of
4036 // LookupParsedName.
4037 if (ObjCMethodDecl *Method = SemaRef.getCurMethodDecl()) {
4038 if (Method->isInstanceMethod() && Method->getClassInterface() &&
4040 (Res.isSingleResult() &&
4041 Res.getFoundDecl()->isDefinedOutsideFunctionOrMethod()))) {
4042 if (ObjCIvarDecl *IV
4043 = Method->getClassInterface()->lookupInstanceVariable(Name)) {
4051 /// \brief Add keywords to the consumer as possible typo corrections.
4052 static void AddKeywordsToConsumer(Sema &SemaRef,
4053 TypoCorrectionConsumer &Consumer,
4054 Scope *S, CorrectionCandidateCallback &CCC,
4055 bool AfterNestedNameSpecifier) {
4056 if (AfterNestedNameSpecifier) {
4057 // For 'X::', we know exactly which keywords can appear next.
4058 Consumer.addKeywordResult("template");
4059 if (CCC.WantExpressionKeywords)
4060 Consumer.addKeywordResult("operator");
4064 if (CCC.WantObjCSuper)
4065 Consumer.addKeywordResult("super");
4067 if (CCC.WantTypeSpecifiers) {
4068 // Add type-specifier keywords to the set of results.
4069 static const char *const CTypeSpecs[] = {
4070 "char", "const", "double", "enum", "float", "int", "long", "short",
4071 "signed", "struct", "union", "unsigned", "void", "volatile",
4072 "_Complex", "_Imaginary",
4073 // storage-specifiers as well
4074 "extern", "inline", "static", "typedef"
4077 const unsigned NumCTypeSpecs = llvm::array_lengthof(CTypeSpecs);
4078 for (unsigned I = 0; I != NumCTypeSpecs; ++I)
4079 Consumer.addKeywordResult(CTypeSpecs[I]);
4081 if (SemaRef.getLangOpts().C99)
4082 Consumer.addKeywordResult("restrict");
4083 if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus)
4084 Consumer.addKeywordResult("bool");
4085 else if (SemaRef.getLangOpts().C99)
4086 Consumer.addKeywordResult("_Bool");
4088 if (SemaRef.getLangOpts().CPlusPlus) {
4089 Consumer.addKeywordResult("class");
4090 Consumer.addKeywordResult("typename");
4091 Consumer.addKeywordResult("wchar_t");
4093 if (SemaRef.getLangOpts().CPlusPlus11) {
4094 Consumer.addKeywordResult("char16_t");
4095 Consumer.addKeywordResult("char32_t");
4096 Consumer.addKeywordResult("constexpr");
4097 Consumer.addKeywordResult("decltype");
4098 Consumer.addKeywordResult("thread_local");
4102 if (SemaRef.getLangOpts().GNUMode)
4103 Consumer.addKeywordResult("typeof");
4104 } else if (CCC.WantFunctionLikeCasts) {
4105 static const char *const CastableTypeSpecs[] = {
4106 "char", "double", "float", "int", "long", "short",
4107 "signed", "unsigned", "void"
4109 for (auto *kw : CastableTypeSpecs)
4110 Consumer.addKeywordResult(kw);
4113 if (CCC.WantCXXNamedCasts && SemaRef.getLangOpts().CPlusPlus) {
4114 Consumer.addKeywordResult("const_cast");
4115 Consumer.addKeywordResult("dynamic_cast");
4116 Consumer.addKeywordResult("reinterpret_cast");
4117 Consumer.addKeywordResult("static_cast");
4120 if (CCC.WantExpressionKeywords) {
4121 Consumer.addKeywordResult("sizeof");
4122 if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus) {
4123 Consumer.addKeywordResult("false");
4124 Consumer.addKeywordResult("true");
4127 if (SemaRef.getLangOpts().CPlusPlus) {
4128 static const char *const CXXExprs[] = {
4129 "delete", "new", "operator", "throw", "typeid"
4131 const unsigned NumCXXExprs = llvm::array_lengthof(CXXExprs);
4132 for (unsigned I = 0; I != NumCXXExprs; ++I)
4133 Consumer.addKeywordResult(CXXExprs[I]);
4135 if (isa<CXXMethodDecl>(SemaRef.CurContext) &&
4136 cast<CXXMethodDecl>(SemaRef.CurContext)->isInstance())
4137 Consumer.addKeywordResult("this");
4139 if (SemaRef.getLangOpts().CPlusPlus11) {
4140 Consumer.addKeywordResult("alignof");
4141 Consumer.addKeywordResult("nullptr");
4145 if (SemaRef.getLangOpts().C11) {
4146 // FIXME: We should not suggest _Alignof if the alignof macro
4148 Consumer.addKeywordResult("_Alignof");
4152 if (CCC.WantRemainingKeywords) {
4153 if (SemaRef.getCurFunctionOrMethodDecl() || SemaRef.getCurBlock()) {
4155 static const char *const CStmts[] = {
4156 "do", "else", "for", "goto", "if", "return", "switch", "while" };
4157 const unsigned NumCStmts = llvm::array_lengthof(CStmts);
4158 for (unsigned I = 0; I != NumCStmts; ++I)
4159 Consumer.addKeywordResult(CStmts[I]);
4161 if (SemaRef.getLangOpts().CPlusPlus) {
4162 Consumer.addKeywordResult("catch");
4163 Consumer.addKeywordResult("try");
4166 if (S && S->getBreakParent())
4167 Consumer.addKeywordResult("break");
4169 if (S && S->getContinueParent())
4170 Consumer.addKeywordResult("continue");
4172 if (!SemaRef.getCurFunction()->SwitchStack.empty()) {
4173 Consumer.addKeywordResult("case");
4174 Consumer.addKeywordResult("default");
4177 if (SemaRef.getLangOpts().CPlusPlus) {
4178 Consumer.addKeywordResult("namespace");
4179 Consumer.addKeywordResult("template");
4182 if (S && S->isClassScope()) {
4183 Consumer.addKeywordResult("explicit");
4184 Consumer.addKeywordResult("friend");
4185 Consumer.addKeywordResult("mutable");
4186 Consumer.addKeywordResult("private");
4187 Consumer.addKeywordResult("protected");
4188 Consumer.addKeywordResult("public");
4189 Consumer.addKeywordResult("virtual");
4193 if (SemaRef.getLangOpts().CPlusPlus) {
4194 Consumer.addKeywordResult("using");
4196 if (SemaRef.getLangOpts().CPlusPlus11)
4197 Consumer.addKeywordResult("static_assert");
4202 std::unique_ptr<TypoCorrectionConsumer> Sema::makeTypoCorrectionConsumer(
4203 const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
4204 Scope *S, CXXScopeSpec *SS,
4205 std::unique_ptr<CorrectionCandidateCallback> CCC,
4206 DeclContext *MemberContext, bool EnteringContext,
4207 const ObjCObjectPointerType *OPT, bool ErrorRecovery) {
4209 if (Diags.hasFatalErrorOccurred() || !getLangOpts().SpellChecking ||
4210 DisableTypoCorrection)
4213 // In Microsoft mode, don't perform typo correction in a template member
4214 // function dependent context because it interferes with the "lookup into
4215 // dependent bases of class templates" feature.
4216 if (getLangOpts().MSVCCompat && CurContext->isDependentContext() &&
4217 isa<CXXMethodDecl>(CurContext))
4220 // We only attempt to correct typos for identifiers.
4221 IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4225 // If the scope specifier itself was invalid, don't try to correct
4227 if (SS && SS->isInvalid())
4230 // Never try to correct typos during template deduction or
4232 if (!ActiveTemplateInstantiations.empty())
4235 // Don't try to correct 'super'.
4236 if (S && S->isInObjcMethodScope() && Typo == getSuperIdentifier())
4239 // Abort if typo correction already failed for this specific typo.
4240 IdentifierSourceLocations::iterator locs = TypoCorrectionFailures.find(Typo);
4241 if (locs != TypoCorrectionFailures.end() &&
4242 locs->second.count(TypoName.getLoc()))
4245 // Don't try to correct the identifier "vector" when in AltiVec mode.
4246 // TODO: Figure out why typo correction misbehaves in this case, fix it, and
4247 // remove this workaround.
4248 if ((getLangOpts().AltiVec || getLangOpts().ZVector) && Typo->isStr("vector"))
4251 // Provide a stop gap for files that are just seriously broken. Trying
4252 // to correct all typos can turn into a HUGE performance penalty, causing
4253 // some files to take minutes to get rejected by the parser.
4254 unsigned Limit = getDiagnostics().getDiagnosticOptions().SpellCheckingLimit;
4255 if (Limit && TyposCorrected >= Limit)
4259 // If we're handling a missing symbol error, using modules, and the
4260 // special search all modules option is used, look for a missing import.
4261 if (ErrorRecovery && getLangOpts().Modules &&
4262 getLangOpts().ModulesSearchAll) {
4263 // The following has the side effect of loading the missing module.
4264 getModuleLoader().lookupMissingImports(Typo->getName(),
4265 TypoName.getLocStart());
4268 CorrectionCandidateCallback &CCCRef = *CCC;
4269 auto Consumer = llvm::make_unique<TypoCorrectionConsumer>(
4270 *this, TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4273 // Perform name lookup to find visible, similarly-named entities.
4274 bool IsUnqualifiedLookup = false;
4275 DeclContext *QualifiedDC = MemberContext;
4276 if (MemberContext) {
4277 LookupVisibleDecls(MemberContext, LookupKind, *Consumer);
4279 // Look in qualified interfaces.
4281 for (auto *I : OPT->quals())
4282 LookupVisibleDecls(I, LookupKind, *Consumer);
4284 } else if (SS && SS->isSet()) {
4285 QualifiedDC = computeDeclContext(*SS, EnteringContext);
4289 LookupVisibleDecls(QualifiedDC, LookupKind, *Consumer);
4291 IsUnqualifiedLookup = true;
4294 // Determine whether we are going to search in the various namespaces for
4296 bool SearchNamespaces
4297 = getLangOpts().CPlusPlus &&
4298 (IsUnqualifiedLookup || (SS && SS->isSet()));
4300 if (IsUnqualifiedLookup || SearchNamespaces) {
4301 // For unqualified lookup, look through all of the names that we have
4302 // seen in this translation unit.
4303 // FIXME: Re-add the ability to skip very unlikely potential corrections.
4304 for (const auto &I : Context.Idents)
4305 Consumer->FoundName(I.getKey());
4307 // Walk through identifiers in external identifier sources.
4308 // FIXME: Re-add the ability to skip very unlikely potential corrections.
4309 if (IdentifierInfoLookup *External
4310 = Context.Idents.getExternalIdentifierLookup()) {
4311 std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
4313 StringRef Name = Iter->Next();
4317 Consumer->FoundName(Name);
4322 AddKeywordsToConsumer(*this, *Consumer, S, CCCRef, SS && SS->isNotEmpty());
4324 // Build the NestedNameSpecifiers for the KnownNamespaces, if we're going
4325 // to search those namespaces.
4326 if (SearchNamespaces) {
4327 // Load any externally-known namespaces.
4328 if (ExternalSource && !LoadedExternalKnownNamespaces) {
4329 SmallVector<NamespaceDecl *, 4> ExternalKnownNamespaces;
4330 LoadedExternalKnownNamespaces = true;
4331 ExternalSource->ReadKnownNamespaces(ExternalKnownNamespaces);
4332 for (auto *N : ExternalKnownNamespaces)
4333 KnownNamespaces[N] = true;
4336 Consumer->addNamespaces(KnownNamespaces);
4342 /// \brief Try to "correct" a typo in the source code by finding
4343 /// visible declarations whose names are similar to the name that was
4344 /// present in the source code.
4346 /// \param TypoName the \c DeclarationNameInfo structure that contains
4347 /// the name that was present in the source code along with its location.
4349 /// \param LookupKind the name-lookup criteria used to search for the name.
4351 /// \param S the scope in which name lookup occurs.
4353 /// \param SS the nested-name-specifier that precedes the name we're
4354 /// looking for, if present.
4356 /// \param CCC A CorrectionCandidateCallback object that provides further
4357 /// validation of typo correction candidates. It also provides flags for
4358 /// determining the set of keywords permitted.
4360 /// \param MemberContext if non-NULL, the context in which to look for
4361 /// a member access expression.
4363 /// \param EnteringContext whether we're entering the context described by
4364 /// the nested-name-specifier SS.
4366 /// \param OPT when non-NULL, the search for visible declarations will
4367 /// also walk the protocols in the qualified interfaces of \p OPT.
4369 /// \returns a \c TypoCorrection containing the corrected name if the typo
4370 /// along with information such as the \c NamedDecl where the corrected name
4371 /// was declared, and any additional \c NestedNameSpecifier needed to access
4372 /// it (C++ only). The \c TypoCorrection is empty if there is no correction.
4373 TypoCorrection Sema::CorrectTypo(const DeclarationNameInfo &TypoName,
4374 Sema::LookupNameKind LookupKind,
4375 Scope *S, CXXScopeSpec *SS,
4376 std::unique_ptr<CorrectionCandidateCallback> CCC,
4377 CorrectTypoKind Mode,
4378 DeclContext *MemberContext,
4379 bool EnteringContext,
4380 const ObjCObjectPointerType *OPT,
4381 bool RecordFailure) {
4382 assert(CCC && "CorrectTypo requires a CorrectionCandidateCallback");
4384 // Always let the ExternalSource have the first chance at correction, even
4385 // if we would otherwise have given up.
4386 if (ExternalSource) {
4387 if (TypoCorrection Correction = ExternalSource->CorrectTypo(
4388 TypoName, LookupKind, S, SS, *CCC, MemberContext, EnteringContext, OPT))
4392 // Ugly hack equivalent to CTC == CTC_ObjCMessageReceiver;
4393 // WantObjCSuper is only true for CTC_ObjCMessageReceiver and for
4394 // some instances of CTC_Unknown, while WantRemainingKeywords is true
4395 // for CTC_Unknown but not for CTC_ObjCMessageReceiver.
4396 bool ObjCMessageReceiver = CCC->WantObjCSuper && !CCC->WantRemainingKeywords;
4398 IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4399 auto Consumer = makeTypoCorrectionConsumer(
4400 TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4401 EnteringContext, OPT, Mode == CTK_ErrorRecovery);
4404 return TypoCorrection();
4406 // If we haven't found anything, we're done.
4407 if (Consumer->empty())
4408 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4410 // Make sure the best edit distance (prior to adding any namespace qualifiers)
4411 // is not more that about a third of the length of the typo's identifier.
4412 unsigned ED = Consumer->getBestEditDistance(true);
4413 unsigned TypoLen = Typo->getName().size();
4414 if (ED > 0 && TypoLen / ED < 3)
4415 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4417 TypoCorrection BestTC = Consumer->getNextCorrection();
4418 TypoCorrection SecondBestTC = Consumer->getNextCorrection();
4420 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4422 ED = BestTC.getEditDistance();
4424 if (TypoLen >= 3 && ED > 0 && TypoLen / ED < 3) {
4425 // If this was an unqualified lookup and we believe the callback
4426 // object wouldn't have filtered out possible corrections, note
4427 // that no correction was found.
4428 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4431 // If only a single name remains, return that result.
4432 if (!SecondBestTC ||
4433 SecondBestTC.getEditDistance(false) > BestTC.getEditDistance(false)) {
4434 const TypoCorrection &Result = BestTC;
4436 // Don't correct to a keyword that's the same as the typo; the keyword
4437 // wasn't actually in scope.
4438 if (ED == 0 && Result.isKeyword())
4439 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4441 TypoCorrection TC = Result;
4442 TC.setCorrectionRange(SS, TypoName);
4443 checkCorrectionVisibility(*this, TC);
4445 } else if (SecondBestTC && ObjCMessageReceiver) {
4446 // Prefer 'super' when we're completing in a message-receiver
4449 if (BestTC.getCorrection().getAsString() != "super") {
4450 if (SecondBestTC.getCorrection().getAsString() == "super")
4451 BestTC = SecondBestTC;
4452 else if ((*Consumer)["super"].front().isKeyword())
4453 BestTC = (*Consumer)["super"].front();
4455 // Don't correct to a keyword that's the same as the typo; the keyword
4456 // wasn't actually in scope.
4457 if (BestTC.getEditDistance() == 0 ||
4458 BestTC.getCorrection().getAsString() != "super")
4459 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4461 BestTC.setCorrectionRange(SS, TypoName);
4465 // Record the failure's location if needed and return an empty correction. If
4466 // this was an unqualified lookup and we believe the callback object did not
4467 // filter out possible corrections, also cache the failure for the typo.
4468 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure && !SecondBestTC);
4471 /// \brief Try to "correct" a typo in the source code by finding
4472 /// visible declarations whose names are similar to the name that was
4473 /// present in the source code.
4475 /// \param TypoName the \c DeclarationNameInfo structure that contains
4476 /// the name that was present in the source code along with its location.
4478 /// \param LookupKind the name-lookup criteria used to search for the name.
4480 /// \param S the scope in which name lookup occurs.
4482 /// \param SS the nested-name-specifier that precedes the name we're
4483 /// looking for, if present.
4485 /// \param CCC A CorrectionCandidateCallback object that provides further
4486 /// validation of typo correction candidates. It also provides flags for
4487 /// determining the set of keywords permitted.
4489 /// \param TDG A TypoDiagnosticGenerator functor that will be used to print
4490 /// diagnostics when the actual typo correction is attempted.
4492 /// \param TRC A TypoRecoveryCallback functor that will be used to build an
4493 /// Expr from a typo correction candidate.
4495 /// \param MemberContext if non-NULL, the context in which to look for
4496 /// a member access expression.
4498 /// \param EnteringContext whether we're entering the context described by
4499 /// the nested-name-specifier SS.
4501 /// \param OPT when non-NULL, the search for visible declarations will
4502 /// also walk the protocols in the qualified interfaces of \p OPT.
4504 /// \returns a new \c TypoExpr that will later be replaced in the AST with an
4505 /// Expr representing the result of performing typo correction, or nullptr if
4506 /// typo correction is not possible. If nullptr is returned, no diagnostics will
4507 /// be emitted and it is the responsibility of the caller to emit any that are
4509 TypoExpr *Sema::CorrectTypoDelayed(
4510 const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
4511 Scope *S, CXXScopeSpec *SS,
4512 std::unique_ptr<CorrectionCandidateCallback> CCC,
4513 TypoDiagnosticGenerator TDG, TypoRecoveryCallback TRC, CorrectTypoKind Mode,
4514 DeclContext *MemberContext, bool EnteringContext,
4515 const ObjCObjectPointerType *OPT) {
4516 assert(CCC && "CorrectTypoDelayed requires a CorrectionCandidateCallback");
4518 TypoCorrection Empty;
4519 auto Consumer = makeTypoCorrectionConsumer(
4520 TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4521 EnteringContext, OPT, Mode == CTK_ErrorRecovery);
4523 if (!Consumer || Consumer->empty())
4526 // Make sure the best edit distance (prior to adding any namespace qualifiers)
4527 // is not more that about a third of the length of the typo's identifier.
4528 unsigned ED = Consumer->getBestEditDistance(true);
4529 IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4530 if (ED > 0 && Typo->getName().size() / ED < 3)
4533 ExprEvalContexts.back().NumTypos++;
4534 return createDelayedTypo(std::move(Consumer), std::move(TDG), std::move(TRC));
4537 void TypoCorrection::addCorrectionDecl(NamedDecl *CDecl) {
4541 CorrectionDecls.clear();
4543 CorrectionDecls.push_back(CDecl->getUnderlyingDecl());
4545 if (!CorrectionName)
4546 CorrectionName = CDecl->getDeclName();
4549 std::string TypoCorrection::getAsString(const LangOptions &LO) const {
4550 if (CorrectionNameSpec) {
4551 std::string tmpBuffer;
4552 llvm::raw_string_ostream PrefixOStream(tmpBuffer);
4553 CorrectionNameSpec->print(PrefixOStream, PrintingPolicy(LO));
4554 PrefixOStream << CorrectionName;
4555 return PrefixOStream.str();
4558 return CorrectionName.getAsString();
4561 bool CorrectionCandidateCallback::ValidateCandidate(
4562 const TypoCorrection &candidate) {
4563 if (!candidate.isResolved())
4566 if (candidate.isKeyword())
4567 return WantTypeSpecifiers || WantExpressionKeywords || WantCXXNamedCasts ||
4568 WantRemainingKeywords || WantObjCSuper;
4570 bool HasNonType = false;
4571 bool HasStaticMethod = false;
4572 bool HasNonStaticMethod = false;
4573 for (Decl *D : candidate) {
4574 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(D))
4575 D = FTD->getTemplatedDecl();
4576 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
4577 if (Method->isStatic())
4578 HasStaticMethod = true;
4580 HasNonStaticMethod = true;
4582 if (!isa<TypeDecl>(D))
4586 if (IsAddressOfOperand && HasNonStaticMethod && !HasStaticMethod &&
4587 !candidate.getCorrectionSpecifier())
4590 return WantTypeSpecifiers || HasNonType;
4593 FunctionCallFilterCCC::FunctionCallFilterCCC(Sema &SemaRef, unsigned NumArgs,
4594 bool HasExplicitTemplateArgs,
4596 : NumArgs(NumArgs), HasExplicitTemplateArgs(HasExplicitTemplateArgs),
4597 CurContext(SemaRef.CurContext), MemberFn(ME) {
4598 WantTypeSpecifiers = false;
4599 WantFunctionLikeCasts = SemaRef.getLangOpts().CPlusPlus && NumArgs == 1;
4600 WantRemainingKeywords = false;
4603 bool FunctionCallFilterCCC::ValidateCandidate(const TypoCorrection &candidate) {
4604 if (!candidate.getCorrectionDecl())
4605 return candidate.isKeyword();
4607 for (auto *C : candidate) {
4608 FunctionDecl *FD = nullptr;
4609 NamedDecl *ND = C->getUnderlyingDecl();
4610 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
4611 FD = FTD->getTemplatedDecl();
4612 if (!HasExplicitTemplateArgs && !FD) {
4613 if (!(FD = dyn_cast<FunctionDecl>(ND)) && isa<ValueDecl>(ND)) {
4614 // If the Decl is neither a function nor a template function,
4615 // determine if it is a pointer or reference to a function. If so,
4616 // check against the number of arguments expected for the pointee.
4617 QualType ValType = cast<ValueDecl>(ND)->getType();
4618 if (ValType->isAnyPointerType() || ValType->isReferenceType())
4619 ValType = ValType->getPointeeType();
4620 if (const FunctionProtoType *FPT = ValType->getAs<FunctionProtoType>())
4621 if (FPT->getNumParams() == NumArgs)
4626 // Skip the current candidate if it is not a FunctionDecl or does not accept
4627 // the current number of arguments.
4628 if (!FD || !(FD->getNumParams() >= NumArgs &&
4629 FD->getMinRequiredArguments() <= NumArgs))
4632 // If the current candidate is a non-static C++ method, skip the candidate
4633 // unless the method being corrected--or the current DeclContext, if the
4634 // function being corrected is not a method--is a method in the same class
4635 // or a descendent class of the candidate's parent class.
4636 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
4637 if (MemberFn || !MD->isStatic()) {
4638 CXXMethodDecl *CurMD =
4640 ? dyn_cast_or_null<CXXMethodDecl>(MemberFn->getMemberDecl())
4641 : dyn_cast_or_null<CXXMethodDecl>(CurContext);
4642 CXXRecordDecl *CurRD =
4643 CurMD ? CurMD->getParent()->getCanonicalDecl() : nullptr;
4644 CXXRecordDecl *RD = MD->getParent()->getCanonicalDecl();
4645 if (!CurRD || (CurRD != RD && !CurRD->isDerivedFrom(RD)))
4654 void Sema::diagnoseTypo(const TypoCorrection &Correction,
4655 const PartialDiagnostic &TypoDiag,
4656 bool ErrorRecovery) {
4657 diagnoseTypo(Correction, TypoDiag, PDiag(diag::note_previous_decl),
4661 /// Find which declaration we should import to provide the definition of
4662 /// the given declaration.
4663 static NamedDecl *getDefinitionToImport(NamedDecl *D) {
4664 if (VarDecl *VD = dyn_cast<VarDecl>(D))
4665 return VD->getDefinition();
4666 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
4667 return FD->isDefined(FD) ? const_cast<FunctionDecl*>(FD) : nullptr;
4668 if (TagDecl *TD = dyn_cast<TagDecl>(D))
4669 return TD->getDefinition();
4670 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(D))
4671 return ID->getDefinition();
4672 if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl>(D))
4673 return PD->getDefinition();
4674 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
4675 return getDefinitionToImport(TD->getTemplatedDecl());
4679 void Sema::diagnoseMissingImport(SourceLocation Loc, NamedDecl *Decl,
4680 bool NeedDefinition, bool Recover) {
4681 assert(!isVisible(Decl) && "missing import for non-hidden decl?");
4683 // Suggest importing a module providing the definition of this entity, if
4685 NamedDecl *Def = getDefinitionToImport(Decl);
4689 // FIXME: Add a Fix-It that imports the corresponding module or includes
4691 Module *Owner = getOwningModule(Decl);
4692 assert(Owner && "definition of hidden declaration is not in a module");
4694 llvm::SmallVector<Module*, 8> OwningModules;
4695 OwningModules.push_back(Owner);
4696 auto Merged = Context.getModulesWithMergedDefinition(Decl);
4697 OwningModules.insert(OwningModules.end(), Merged.begin(), Merged.end());
4699 diagnoseMissingImport(Loc, Decl, Decl->getLocation(), OwningModules,
4700 NeedDefinition ? MissingImportKind::Definition
4701 : MissingImportKind::Declaration,
4705 void Sema::diagnoseMissingImport(SourceLocation UseLoc, NamedDecl *Decl,
4706 SourceLocation DeclLoc,
4707 ArrayRef<Module *> Modules,
4708 MissingImportKind MIK, bool Recover) {
4709 assert(!Modules.empty());
4711 if (Modules.size() > 1) {
4712 std::string ModuleList;
4714 for (Module *M : Modules) {
4715 ModuleList += "\n ";
4716 if (++N == 5 && N != Modules.size()) {
4717 ModuleList += "[...]";
4720 ModuleList += M->getFullModuleName();
4723 Diag(UseLoc, diag::err_module_unimported_use_multiple)
4724 << (int)MIK << Decl << ModuleList;
4726 Diag(UseLoc, diag::err_module_unimported_use)
4727 << (int)MIK << Decl << Modules[0]->getFullModuleName();
4732 case MissingImportKind::Declaration:
4733 DiagID = diag::note_previous_declaration;
4735 case MissingImportKind::Definition:
4736 DiagID = diag::note_previous_definition;
4738 case MissingImportKind::DefaultArgument:
4739 DiagID = diag::note_default_argument_declared_here;
4742 Diag(DeclLoc, DiagID);
4744 // Try to recover by implicitly importing this module.
4746 createImplicitModuleImportForErrorRecovery(UseLoc, Modules[0]);
4749 /// \brief Diagnose a successfully-corrected typo. Separated from the correction
4750 /// itself to allow external validation of the result, etc.
4752 /// \param Correction The result of performing typo correction.
4753 /// \param TypoDiag The diagnostic to produce. This will have the corrected
4754 /// string added to it (and usually also a fixit).
4755 /// \param PrevNote A note to use when indicating the location of the entity to
4756 /// which we are correcting. Will have the correction string added to it.
4757 /// \param ErrorRecovery If \c true (the default), the caller is going to
4758 /// recover from the typo as if the corrected string had been typed.
4759 /// In this case, \c PDiag must be an error, and we will attach a fixit
4761 void Sema::diagnoseTypo(const TypoCorrection &Correction,
4762 const PartialDiagnostic &TypoDiag,
4763 const PartialDiagnostic &PrevNote,
4764 bool ErrorRecovery) {
4765 std::string CorrectedStr = Correction.getAsString(getLangOpts());
4766 std::string CorrectedQuotedStr = Correction.getQuoted(getLangOpts());
4767 FixItHint FixTypo = FixItHint::CreateReplacement(
4768 Correction.getCorrectionRange(), CorrectedStr);
4770 // Maybe we're just missing a module import.
4771 if (Correction.requiresImport()) {
4772 NamedDecl *Decl = Correction.getCorrectionDecl();
4773 assert(Decl && "import required but no declaration to import");
4775 diagnoseMissingImport(Correction.getCorrectionRange().getBegin(), Decl,
4776 /*NeedDefinition*/ false, ErrorRecovery);
4780 Diag(Correction.getCorrectionRange().getBegin(), TypoDiag)
4781 << CorrectedQuotedStr << (ErrorRecovery ? FixTypo : FixItHint());
4783 NamedDecl *ChosenDecl =
4784 Correction.isKeyword() ? nullptr : Correction.getCorrectionDecl();
4785 if (PrevNote.getDiagID() && ChosenDecl)
4786 Diag(ChosenDecl->getLocation(), PrevNote)
4787 << CorrectedQuotedStr << (ErrorRecovery ? FixItHint() : FixTypo);
4790 TypoExpr *Sema::createDelayedTypo(std::unique_ptr<TypoCorrectionConsumer> TCC,
4791 TypoDiagnosticGenerator TDG,
4792 TypoRecoveryCallback TRC) {
4793 assert(TCC && "createDelayedTypo requires a valid TypoCorrectionConsumer");
4794 auto TE = new (Context) TypoExpr(Context.DependentTy);
4795 auto &State = DelayedTypos[TE];
4796 State.Consumer = std::move(TCC);
4797 State.DiagHandler = std::move(TDG);
4798 State.RecoveryHandler = std::move(TRC);
4802 const Sema::TypoExprState &Sema::getTypoExprState(TypoExpr *TE) const {
4803 auto Entry = DelayedTypos.find(TE);
4804 assert(Entry != DelayedTypos.end() &&
4805 "Failed to get the state for a TypoExpr!");
4806 return Entry->second;
4809 void Sema::clearDelayedTypo(TypoExpr *TE) {
4810 DelayedTypos.erase(TE);