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 //===----------------------------------------------------------------------===//
15 #include "clang/Sema/Lookup.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/ASTMutationListener.h"
18 #include "clang/AST/CXXInheritance.h"
19 #include "clang/AST/Decl.h"
20 #include "clang/AST/DeclCXX.h"
21 #include "clang/AST/DeclLookups.h"
22 #include "clang/AST/DeclObjC.h"
23 #include "clang/AST/DeclTemplate.h"
24 #include "clang/AST/Expr.h"
25 #include "clang/AST/ExprCXX.h"
26 #include "clang/Basic/Builtins.h"
27 #include "clang/Basic/LangOptions.h"
28 #include "clang/Lex/HeaderSearch.h"
29 #include "clang/Lex/ModuleLoader.h"
30 #include "clang/Lex/Preprocessor.h"
31 #include "clang/Sema/DeclSpec.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()));
207 } // end anonymous namespace
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::LookupOMPReductionName:
283 IDNS = Decl::IDNS_OMPReduction;
286 case Sema::LookupAnyName:
287 IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag | Decl::IDNS_Member
288 | Decl::IDNS_Using | Decl::IDNS_Namespace | Decl::IDNS_ObjCProtocol
295 void LookupResult::configure() {
296 IDNS = getIDNS(LookupKind, getSema().getLangOpts().CPlusPlus,
297 isForRedeclaration());
299 // If we're looking for one of the allocation or deallocation
300 // operators, make sure that the implicitly-declared new and delete
301 // operators can be found.
302 switch (NameInfo.getName().getCXXOverloadedOperator()) {
306 case OO_Array_Delete:
307 getSema().DeclareGlobalNewDelete();
314 // Compiler builtins are always visible, regardless of where they end
315 // up being declared.
316 if (IdentifierInfo *Id = NameInfo.getName().getAsIdentifierInfo()) {
317 if (unsigned BuiltinID = Id->getBuiltinID()) {
318 if (!getSema().Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
324 bool LookupResult::sanity() const {
325 // This function is never called by NDEBUG builds.
326 assert(ResultKind != NotFound || Decls.size() == 0);
327 assert(ResultKind != Found || Decls.size() == 1);
328 assert(ResultKind != FoundOverloaded || Decls.size() > 1 ||
329 (Decls.size() == 1 &&
330 isa<FunctionTemplateDecl>((*begin())->getUnderlyingDecl())));
331 assert(ResultKind != FoundUnresolvedValue || sanityCheckUnresolved());
332 assert(ResultKind != Ambiguous || Decls.size() > 1 ||
333 (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects ||
334 Ambiguity == AmbiguousBaseSubobjectTypes)));
335 assert((Paths != nullptr) == (ResultKind == Ambiguous &&
336 (Ambiguity == AmbiguousBaseSubobjectTypes ||
337 Ambiguity == AmbiguousBaseSubobjects)));
341 // Necessary because CXXBasePaths is not complete in Sema.h
342 void LookupResult::deletePaths(CXXBasePaths *Paths) {
346 /// Get a representative context for a declaration such that two declarations
347 /// will have the same context if they were found within the same scope.
348 static DeclContext *getContextForScopeMatching(Decl *D) {
349 // For function-local declarations, use that function as the context. This
350 // doesn't account for scopes within the function; the caller must deal with
352 DeclContext *DC = D->getLexicalDeclContext();
353 if (DC->isFunctionOrMethod())
356 // Otherwise, look at the semantic context of the declaration. The
357 // declaration must have been found there.
358 return D->getDeclContext()->getRedeclContext();
361 /// \brief Determine whether \p D is a better lookup result than \p Existing,
362 /// given that they declare the same entity.
363 static bool isPreferredLookupResult(Sema &S, Sema::LookupNameKind Kind,
364 NamedDecl *D, NamedDecl *Existing) {
365 // When looking up redeclarations of a using declaration, prefer a using
366 // shadow declaration over any other declaration of the same entity.
367 if (Kind == Sema::LookupUsingDeclName && isa<UsingShadowDecl>(D) &&
368 !isa<UsingShadowDecl>(Existing))
371 auto *DUnderlying = D->getUnderlyingDecl();
372 auto *EUnderlying = Existing->getUnderlyingDecl();
374 // If they have different underlying declarations, prefer a typedef over the
375 // original type (this happens when two type declarations denote the same
376 // type), per a generous reading of C++ [dcl.typedef]p3 and p4. The typedef
377 // might carry additional semantic information, such as an alignment override.
378 // However, per C++ [dcl.typedef]p5, when looking up a tag name, prefer a tag
379 // declaration over a typedef.
380 if (DUnderlying->getCanonicalDecl() != EUnderlying->getCanonicalDecl()) {
381 assert(isa<TypeDecl>(DUnderlying) && isa<TypeDecl>(EUnderlying));
382 bool HaveTag = isa<TagDecl>(EUnderlying);
383 bool WantTag = Kind == Sema::LookupTagName;
384 return HaveTag != WantTag;
387 // Pick the function with more default arguments.
388 // FIXME: In the presence of ambiguous default arguments, we should keep both,
389 // so we can diagnose the ambiguity if the default argument is needed.
390 // See C++ [over.match.best]p3.
391 if (auto *DFD = dyn_cast<FunctionDecl>(DUnderlying)) {
392 auto *EFD = cast<FunctionDecl>(EUnderlying);
393 unsigned DMin = DFD->getMinRequiredArguments();
394 unsigned EMin = EFD->getMinRequiredArguments();
395 // If D has more default arguments, it is preferred.
398 // FIXME: When we track visibility for default function arguments, check
399 // that we pick the declaration with more visible default arguments.
402 // Pick the template with more default template arguments.
403 if (auto *DTD = dyn_cast<TemplateDecl>(DUnderlying)) {
404 auto *ETD = cast<TemplateDecl>(EUnderlying);
405 unsigned DMin = DTD->getTemplateParameters()->getMinRequiredArguments();
406 unsigned EMin = ETD->getTemplateParameters()->getMinRequiredArguments();
407 // If D has more default arguments, it is preferred. Note that default
408 // arguments (and their visibility) is monotonically increasing across the
409 // redeclaration chain, so this is a quick proxy for "is more recent".
412 // If D has more *visible* default arguments, it is preferred. Note, an
413 // earlier default argument being visible does not imply that a later
414 // default argument is visible, so we can't just check the first one.
415 for (unsigned I = DMin, N = DTD->getTemplateParameters()->size();
417 if (!S.hasVisibleDefaultArgument(
418 ETD->getTemplateParameters()->getParam(I)) &&
419 S.hasVisibleDefaultArgument(
420 DTD->getTemplateParameters()->getParam(I)))
425 // VarDecl can have incomplete array types, prefer the one with more complete
427 if (VarDecl *DVD = dyn_cast<VarDecl>(DUnderlying)) {
428 VarDecl *EVD = cast<VarDecl>(EUnderlying);
429 if (EVD->getType()->isIncompleteType() &&
430 !DVD->getType()->isIncompleteType()) {
431 // Prefer the decl with a more complete type if visible.
432 return S.isVisible(DVD);
434 return false; // Avoid picking up a newer decl, just because it was newer.
437 // For most kinds of declaration, it doesn't really matter which one we pick.
438 if (!isa<FunctionDecl>(DUnderlying) && !isa<VarDecl>(DUnderlying)) {
439 // If the existing declaration is hidden, prefer the new one. Otherwise,
440 // keep what we've got.
441 return !S.isVisible(Existing);
444 // Pick the newer declaration; it might have a more precise type.
445 for (Decl *Prev = DUnderlying->getPreviousDecl(); Prev;
446 Prev = Prev->getPreviousDecl())
447 if (Prev == EUnderlying)
452 /// Determine whether \p D can hide a tag declaration.
453 static bool canHideTag(NamedDecl *D) {
454 // C++ [basic.scope.declarative]p4:
455 // Given a set of declarations in a single declarative region [...]
456 // exactly one declaration shall declare a class name or enumeration name
457 // that is not a typedef name and the other declarations shall all refer to
458 // the same variable or enumerator, or all refer to functions and function
459 // templates; in this case the class name or enumeration name is hidden.
460 // C++ [basic.scope.hiding]p2:
461 // A class name or enumeration name can be hidden by the name of a
462 // variable, data member, function, or enumerator declared in the same
464 D = D->getUnderlyingDecl();
465 return isa<VarDecl>(D) || isa<EnumConstantDecl>(D) || isa<FunctionDecl>(D) ||
466 isa<FunctionTemplateDecl>(D) || isa<FieldDecl>(D);
469 /// Resolves the result kind of this lookup.
470 void LookupResult::resolveKind() {
471 unsigned N = Decls.size();
473 // Fast case: no possible ambiguity.
475 assert(ResultKind == NotFound ||
476 ResultKind == NotFoundInCurrentInstantiation);
480 // If there's a single decl, we need to examine it to decide what
481 // kind of lookup this is.
483 NamedDecl *D = (*Decls.begin())->getUnderlyingDecl();
484 if (isa<FunctionTemplateDecl>(D))
485 ResultKind = FoundOverloaded;
486 else if (isa<UnresolvedUsingValueDecl>(D))
487 ResultKind = FoundUnresolvedValue;
491 // Don't do any extra resolution if we've already resolved as ambiguous.
492 if (ResultKind == Ambiguous) return;
494 llvm::SmallDenseMap<NamedDecl*, unsigned, 16> Unique;
495 llvm::SmallDenseMap<QualType, unsigned, 16> UniqueTypes;
497 bool Ambiguous = false;
498 bool HasTag = false, HasFunction = false;
499 bool HasFunctionTemplate = false, HasUnresolved = false;
500 NamedDecl *HasNonFunction = nullptr;
502 llvm::SmallVector<NamedDecl*, 4> EquivalentNonFunctions;
504 unsigned UniqueTagIndex = 0;
508 NamedDecl *D = Decls[I]->getUnderlyingDecl();
509 D = cast<NamedDecl>(D->getCanonicalDecl());
511 // Ignore an invalid declaration unless it's the only one left.
512 if (D->isInvalidDecl() && !(I == 0 && N == 1)) {
513 Decls[I] = Decls[--N];
517 llvm::Optional<unsigned> ExistingI;
519 // Redeclarations of types via typedef can occur both within a scope
520 // and, through using declarations and directives, across scopes. There is
521 // no ambiguity if they all refer to the same type, so unique based on the
523 if (TypeDecl *TD = dyn_cast<TypeDecl>(D)) {
524 QualType T = getSema().Context.getTypeDeclType(TD);
525 auto UniqueResult = UniqueTypes.insert(
526 std::make_pair(getSema().Context.getCanonicalType(T), I));
527 if (!UniqueResult.second) {
528 // The type is not unique.
529 ExistingI = UniqueResult.first->second;
533 // For non-type declarations, check for a prior lookup result naming this
534 // canonical declaration.
536 auto UniqueResult = Unique.insert(std::make_pair(D, I));
537 if (!UniqueResult.second) {
538 // We've seen this entity before.
539 ExistingI = UniqueResult.first->second;
544 // This is not a unique lookup result. Pick one of the results and
545 // discard the other.
546 if (isPreferredLookupResult(getSema(), getLookupKind(), Decls[I],
548 Decls[*ExistingI] = Decls[I];
549 Decls[I] = Decls[--N];
553 // Otherwise, do some decl type analysis and then continue.
555 if (isa<UnresolvedUsingValueDecl>(D)) {
556 HasUnresolved = true;
557 } else if (isa<TagDecl>(D)) {
562 } else if (isa<FunctionTemplateDecl>(D)) {
564 HasFunctionTemplate = true;
565 } else if (isa<FunctionDecl>(D)) {
568 if (HasNonFunction) {
569 // If we're about to create an ambiguity between two declarations that
570 // are equivalent, but one is an internal linkage declaration from one
571 // module and the other is an internal linkage declaration from another
572 // module, just skip it.
573 if (getSema().isEquivalentInternalLinkageDeclaration(HasNonFunction,
575 EquivalentNonFunctions.push_back(D);
576 Decls[I] = Decls[--N];
587 // C++ [basic.scope.hiding]p2:
588 // A class name or enumeration name can be hidden by the name of
589 // an object, function, or enumerator declared in the same
590 // scope. If a class or enumeration name and an object, function,
591 // or enumerator are declared in the same scope (in any order)
592 // with the same name, the class or enumeration name is hidden
593 // wherever the object, function, or enumerator name is visible.
594 // But it's still an error if there are distinct tag types found,
595 // even if they're not visible. (ref?)
596 if (N > 1 && HideTags && HasTag && !Ambiguous &&
597 (HasFunction || HasNonFunction || HasUnresolved)) {
598 NamedDecl *OtherDecl = Decls[UniqueTagIndex ? 0 : N - 1];
599 if (isa<TagDecl>(Decls[UniqueTagIndex]->getUnderlyingDecl()) &&
600 getContextForScopeMatching(Decls[UniqueTagIndex])->Equals(
601 getContextForScopeMatching(OtherDecl)) &&
602 canHideTag(OtherDecl))
603 Decls[UniqueTagIndex] = Decls[--N];
608 // FIXME: This diagnostic should really be delayed until we're done with
609 // the lookup result, in case the ambiguity is resolved by the caller.
610 if (!EquivalentNonFunctions.empty() && !Ambiguous)
611 getSema().diagnoseEquivalentInternalLinkageDeclarations(
612 getNameLoc(), HasNonFunction, EquivalentNonFunctions);
616 if (HasNonFunction && (HasFunction || HasUnresolved))
620 setAmbiguous(LookupResult::AmbiguousReference);
621 else if (HasUnresolved)
622 ResultKind = LookupResult::FoundUnresolvedValue;
623 else if (N > 1 || HasFunctionTemplate)
624 ResultKind = LookupResult::FoundOverloaded;
626 ResultKind = LookupResult::Found;
629 void LookupResult::addDeclsFromBasePaths(const CXXBasePaths &P) {
630 CXXBasePaths::const_paths_iterator I, E;
631 for (I = P.begin(), E = P.end(); I != E; ++I)
632 for (DeclContext::lookup_iterator DI = I->Decls.begin(),
633 DE = I->Decls.end(); DI != DE; ++DI)
637 void LookupResult::setAmbiguousBaseSubobjects(CXXBasePaths &P) {
638 Paths = new CXXBasePaths;
640 addDeclsFromBasePaths(*Paths);
642 setAmbiguous(AmbiguousBaseSubobjects);
645 void LookupResult::setAmbiguousBaseSubobjectTypes(CXXBasePaths &P) {
646 Paths = new CXXBasePaths;
648 addDeclsFromBasePaths(*Paths);
650 setAmbiguous(AmbiguousBaseSubobjectTypes);
653 void LookupResult::print(raw_ostream &Out) {
654 Out << Decls.size() << " result(s)";
655 if (isAmbiguous()) Out << ", ambiguous";
656 if (Paths) Out << ", base paths present";
658 for (iterator I = begin(), E = end(); I != E; ++I) {
664 LLVM_DUMP_METHOD void LookupResult::dump() {
665 llvm::errs() << "lookup results for " << getLookupName().getAsString()
667 for (NamedDecl *D : *this)
671 /// \brief Lookup a builtin function, when name lookup would otherwise
673 static bool LookupBuiltin(Sema &S, LookupResult &R) {
674 Sema::LookupNameKind NameKind = R.getLookupKind();
676 // If we didn't find a use of this identifier, and if the identifier
677 // corresponds to a compiler builtin, create the decl object for the builtin
678 // now, injecting it into translation unit scope, and return it.
679 if (NameKind == Sema::LookupOrdinaryName ||
680 NameKind == Sema::LookupRedeclarationWithLinkage) {
681 IdentifierInfo *II = R.getLookupName().getAsIdentifierInfo();
683 if (S.getLangOpts().CPlusPlus && NameKind == Sema::LookupOrdinaryName) {
684 if (II == S.getASTContext().getMakeIntegerSeqName()) {
685 R.addDecl(S.getASTContext().getMakeIntegerSeqDecl());
687 } else if (II == S.getASTContext().getTypePackElementName()) {
688 R.addDecl(S.getASTContext().getTypePackElementDecl());
693 // If this is a builtin on this (or all) targets, create the decl.
694 if (unsigned BuiltinID = II->getBuiltinID()) {
695 // In C++ and OpenCL (spec v1.2 s6.9.f), we don't have any predefined
696 // library functions like 'malloc'. Instead, we'll just error.
697 if ((S.getLangOpts().CPlusPlus || S.getLangOpts().OpenCL) &&
698 S.Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
701 if (NamedDecl *D = S.LazilyCreateBuiltin((IdentifierInfo *)II,
702 BuiltinID, S.TUScope,
703 R.isForRedeclaration(),
715 /// \brief Determine whether we can declare a special member function within
716 /// the class at this point.
717 static bool CanDeclareSpecialMemberFunction(const CXXRecordDecl *Class) {
718 // We need to have a definition for the class.
719 if (!Class->getDefinition() || Class->isDependentContext())
722 // We can't be in the middle of defining the class.
723 return !Class->isBeingDefined();
726 void Sema::ForceDeclarationOfImplicitMembers(CXXRecordDecl *Class) {
727 if (!CanDeclareSpecialMemberFunction(Class))
730 // If the default constructor has not yet been declared, do so now.
731 if (Class->needsImplicitDefaultConstructor())
732 DeclareImplicitDefaultConstructor(Class);
734 // If the copy constructor has not yet been declared, do so now.
735 if (Class->needsImplicitCopyConstructor())
736 DeclareImplicitCopyConstructor(Class);
738 // If the copy assignment operator has not yet been declared, do so now.
739 if (Class->needsImplicitCopyAssignment())
740 DeclareImplicitCopyAssignment(Class);
742 if (getLangOpts().CPlusPlus11) {
743 // If the move constructor has not yet been declared, do so now.
744 if (Class->needsImplicitMoveConstructor())
745 DeclareImplicitMoveConstructor(Class);
747 // If the move assignment operator has not yet been declared, do so now.
748 if (Class->needsImplicitMoveAssignment())
749 DeclareImplicitMoveAssignment(Class);
752 // If the destructor has not yet been declared, do so now.
753 if (Class->needsImplicitDestructor())
754 DeclareImplicitDestructor(Class);
757 /// \brief Determine whether this is the name of an implicitly-declared
758 /// special member function.
759 static bool isImplicitlyDeclaredMemberFunctionName(DeclarationName Name) {
760 switch (Name.getNameKind()) {
761 case DeclarationName::CXXConstructorName:
762 case DeclarationName::CXXDestructorName:
765 case DeclarationName::CXXOperatorName:
766 return Name.getCXXOverloadedOperator() == OO_Equal;
775 /// \brief If there are any implicit member functions with the given name
776 /// that need to be declared in the given declaration context, do so.
777 static void DeclareImplicitMemberFunctionsWithName(Sema &S,
778 DeclarationName Name,
779 const DeclContext *DC) {
783 switch (Name.getNameKind()) {
784 case DeclarationName::CXXConstructorName:
785 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
786 if (Record->getDefinition() && CanDeclareSpecialMemberFunction(Record)) {
787 CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record);
788 if (Record->needsImplicitDefaultConstructor())
789 S.DeclareImplicitDefaultConstructor(Class);
790 if (Record->needsImplicitCopyConstructor())
791 S.DeclareImplicitCopyConstructor(Class);
792 if (S.getLangOpts().CPlusPlus11 &&
793 Record->needsImplicitMoveConstructor())
794 S.DeclareImplicitMoveConstructor(Class);
798 case DeclarationName::CXXDestructorName:
799 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
800 if (Record->getDefinition() && Record->needsImplicitDestructor() &&
801 CanDeclareSpecialMemberFunction(Record))
802 S.DeclareImplicitDestructor(const_cast<CXXRecordDecl *>(Record));
805 case DeclarationName::CXXOperatorName:
806 if (Name.getCXXOverloadedOperator() != OO_Equal)
809 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) {
810 if (Record->getDefinition() && CanDeclareSpecialMemberFunction(Record)) {
811 CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record);
812 if (Record->needsImplicitCopyAssignment())
813 S.DeclareImplicitCopyAssignment(Class);
814 if (S.getLangOpts().CPlusPlus11 &&
815 Record->needsImplicitMoveAssignment())
816 S.DeclareImplicitMoveAssignment(Class);
826 // Adds all qualifying matches for a name within a decl context to the
827 // given lookup result. Returns true if any matches were found.
828 static bool LookupDirect(Sema &S, LookupResult &R, const DeclContext *DC) {
831 // Lazily declare C++ special member functions.
832 if (S.getLangOpts().CPlusPlus)
833 DeclareImplicitMemberFunctionsWithName(S, R.getLookupName(), DC);
835 // Perform lookup into this declaration context.
836 DeclContext::lookup_result DR = DC->lookup(R.getLookupName());
837 for (DeclContext::lookup_iterator I = DR.begin(), E = DR.end(); I != E;
840 if ((D = R.getAcceptableDecl(D))) {
846 if (!Found && DC->isTranslationUnit() && LookupBuiltin(S, R))
849 if (R.getLookupName().getNameKind()
850 != DeclarationName::CXXConversionFunctionName ||
851 R.getLookupName().getCXXNameType()->isDependentType() ||
852 !isa<CXXRecordDecl>(DC))
856 // A specialization of a conversion function template is not found by
857 // name lookup. Instead, any conversion function templates visible in the
858 // context of the use are considered. [...]
859 const CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
860 if (!Record->isCompleteDefinition())
863 for (CXXRecordDecl::conversion_iterator U = Record->conversion_begin(),
864 UEnd = Record->conversion_end(); U != UEnd; ++U) {
865 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(*U);
869 // When we're performing lookup for the purposes of redeclaration, just
870 // add the conversion function template. When we deduce template
871 // arguments for specializations, we'll end up unifying the return
872 // type of the new declaration with the type of the function template.
873 if (R.isForRedeclaration()) {
874 R.addDecl(ConvTemplate);
880 // [...] For each such operator, if argument deduction succeeds
881 // (14.9.2.3), the resulting specialization is used as if found by
884 // When referencing a conversion function for any purpose other than
885 // a redeclaration (such that we'll be building an expression with the
886 // result), perform template argument deduction and place the
887 // specialization into the result set. We do this to avoid forcing all
888 // callers to perform special deduction for conversion functions.
889 TemplateDeductionInfo Info(R.getNameLoc());
890 FunctionDecl *Specialization = nullptr;
892 const FunctionProtoType *ConvProto
893 = ConvTemplate->getTemplatedDecl()->getType()->getAs<FunctionProtoType>();
894 assert(ConvProto && "Nonsensical conversion function template type");
896 // Compute the type of the function that we would expect the conversion
897 // function to have, if it were to match the name given.
898 // FIXME: Calling convention!
899 FunctionProtoType::ExtProtoInfo EPI = ConvProto->getExtProtoInfo();
900 EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC_C);
901 EPI.ExceptionSpec = EST_None;
902 QualType ExpectedType
903 = R.getSema().Context.getFunctionType(R.getLookupName().getCXXNameType(),
906 // Perform template argument deduction against the type that we would
907 // expect the function to have.
908 if (R.getSema().DeduceTemplateArguments(ConvTemplate, nullptr, ExpectedType,
909 Specialization, Info)
910 == Sema::TDK_Success) {
911 R.addDecl(Specialization);
919 // Performs C++ unqualified lookup into the given file context.
921 CppNamespaceLookup(Sema &S, LookupResult &R, ASTContext &Context,
922 DeclContext *NS, UnqualUsingDirectiveSet &UDirs) {
924 assert(NS && NS->isFileContext() && "CppNamespaceLookup() requires namespace!");
926 // Perform direct name lookup into the LookupCtx.
927 bool Found = LookupDirect(S, R, NS);
929 // Perform direct name lookup into the namespaces nominated by the
930 // using directives whose common ancestor is this namespace.
931 for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(NS))
932 if (LookupDirect(S, R, UUE.getNominatedNamespace()))
940 static bool isNamespaceOrTranslationUnitScope(Scope *S) {
941 if (DeclContext *Ctx = S->getEntity())
942 return Ctx->isFileContext();
946 // Find the next outer declaration context from this scope. This
947 // routine actually returns the semantic outer context, which may
948 // differ from the lexical context (encoded directly in the Scope
949 // stack) when we are parsing a member of a class template. In this
950 // case, the second element of the pair will be true, to indicate that
951 // name lookup should continue searching in this semantic context when
952 // it leaves the current template parameter scope.
953 static std::pair<DeclContext *, bool> findOuterContext(Scope *S) {
954 DeclContext *DC = S->getEntity();
955 DeclContext *Lexical = nullptr;
956 for (Scope *OuterS = S->getParent(); OuterS;
957 OuterS = OuterS->getParent()) {
958 if (OuterS->getEntity()) {
959 Lexical = OuterS->getEntity();
964 // C++ [temp.local]p8:
965 // In the definition of a member of a class template that appears
966 // outside of the namespace containing the class template
967 // definition, the name of a template-parameter hides the name of
968 // a member of this namespace.
975 // template<class T> class B {
980 // template<class C> void N::B<C>::f(C) {
981 // C b; // C is the template parameter, not N::C
984 // In this example, the lexical context we return is the
985 // TranslationUnit, while the semantic context is the namespace N.
986 if (!Lexical || !DC || !S->getParent() ||
987 !S->getParent()->isTemplateParamScope())
988 return std::make_pair(Lexical, false);
990 // Find the outermost template parameter scope.
991 // For the example, this is the scope for the template parameters of
992 // template<class C>.
993 Scope *OutermostTemplateScope = S->getParent();
994 while (OutermostTemplateScope->getParent() &&
995 OutermostTemplateScope->getParent()->isTemplateParamScope())
996 OutermostTemplateScope = OutermostTemplateScope->getParent();
998 // Find the namespace context in which the original scope occurs. In
999 // the example, this is namespace N.
1000 DeclContext *Semantic = DC;
1001 while (!Semantic->isFileContext())
1002 Semantic = Semantic->getParent();
1004 // Find the declaration context just outside of the template
1005 // parameter scope. This is the context in which the template is
1006 // being lexically declaration (a namespace context). In the
1007 // example, this is the global scope.
1008 if (Lexical->isFileContext() && !Lexical->Equals(Semantic) &&
1009 Lexical->Encloses(Semantic))
1010 return std::make_pair(Semantic, true);
1012 return std::make_pair(Lexical, false);
1016 /// An RAII object to specify that we want to find block scope extern
1018 struct FindLocalExternScope {
1019 FindLocalExternScope(LookupResult &R)
1020 : R(R), OldFindLocalExtern(R.getIdentifierNamespace() &
1021 Decl::IDNS_LocalExtern) {
1022 R.setFindLocalExtern(R.getIdentifierNamespace() & Decl::IDNS_Ordinary);
1025 R.setFindLocalExtern(OldFindLocalExtern);
1027 ~FindLocalExternScope() {
1031 bool OldFindLocalExtern;
1033 } // end anonymous namespace
1035 bool Sema::CppLookupName(LookupResult &R, Scope *S) {
1036 assert(getLangOpts().CPlusPlus && "Can perform only C++ lookup");
1038 DeclarationName Name = R.getLookupName();
1039 Sema::LookupNameKind NameKind = R.getLookupKind();
1041 // If this is the name of an implicitly-declared special member function,
1042 // go through the scope stack to implicitly declare
1043 if (isImplicitlyDeclaredMemberFunctionName(Name)) {
1044 for (Scope *PreS = S; PreS; PreS = PreS->getParent())
1045 if (DeclContext *DC = PreS->getEntity())
1046 DeclareImplicitMemberFunctionsWithName(*this, Name, DC);
1049 // Implicitly declare member functions with the name we're looking for, if in
1050 // fact we are in a scope where it matters.
1053 IdentifierResolver::iterator
1054 I = IdResolver.begin(Name),
1055 IEnd = IdResolver.end();
1057 // First we lookup local scope.
1058 // We don't consider using-directives, as per 7.3.4.p1 [namespace.udir]
1059 // ...During unqualified name lookup (3.4.1), the names appear as if
1060 // they were declared in the nearest enclosing namespace which contains
1061 // both the using-directive and the nominated namespace.
1062 // [Note: in this context, "contains" means "contains directly or
1066 // namespace A { int i; }
1070 // using namespace A;
1071 // ++i; // finds local 'i', A::i appears at global scope
1075 UnqualUsingDirectiveSet UDirs;
1076 bool VisitedUsingDirectives = false;
1077 bool LeftStartingScope = false;
1078 DeclContext *OutsideOfTemplateParamDC = nullptr;
1080 // When performing a scope lookup, we want to find local extern decls.
1081 FindLocalExternScope FindLocals(R);
1083 for (; S && !isNamespaceOrTranslationUnitScope(S); S = S->getParent()) {
1084 DeclContext *Ctx = S->getEntity();
1085 bool SearchNamespaceScope = true;
1086 // Check whether the IdResolver has anything in this scope.
1087 for (; I != IEnd && S->isDeclScope(*I); ++I) {
1088 if (NamedDecl *ND = R.getAcceptableDecl(*I)) {
1089 if (NameKind == LookupRedeclarationWithLinkage &&
1090 !(*I)->isTemplateParameter()) {
1091 // If it's a template parameter, we still find it, so we can diagnose
1092 // the invalid redeclaration.
1094 // Determine whether this (or a previous) declaration is
1096 if (!LeftStartingScope && !Initial->isDeclScope(*I))
1097 LeftStartingScope = true;
1099 // If we found something outside of our starting scope that
1100 // does not have linkage, skip it.
1101 if (LeftStartingScope && !((*I)->hasLinkage())) {
1106 // We found something in this scope, we should not look at the
1108 SearchNamespaceScope = false;
1113 if (!SearchNamespaceScope) {
1115 if (S->isClassScope())
1116 if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(Ctx))
1117 R.setNamingClass(Record);
1121 if (NameKind == LookupLocalFriendName && !S->isClassScope()) {
1122 // C++11 [class.friend]p11:
1123 // If a friend declaration appears in a local class and the name
1124 // specified is an unqualified name, a prior declaration is
1125 // looked up without considering scopes that are outside the
1126 // innermost enclosing non-class scope.
1130 if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
1131 S->getParent() && !S->getParent()->isTemplateParamScope()) {
1132 // We've just searched the last template parameter scope and
1133 // found nothing, so look into the contexts between the
1134 // lexical and semantic declaration contexts returned by
1135 // findOuterContext(). This implements the name lookup behavior
1136 // of C++ [temp.local]p8.
1137 Ctx = OutsideOfTemplateParamDC;
1138 OutsideOfTemplateParamDC = nullptr;
1142 DeclContext *OuterCtx;
1143 bool SearchAfterTemplateScope;
1144 std::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
1145 if (SearchAfterTemplateScope)
1146 OutsideOfTemplateParamDC = OuterCtx;
1148 for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
1149 // We do not directly look into transparent contexts, since
1150 // those entities will be found in the nearest enclosing
1151 // non-transparent context.
1152 if (Ctx->isTransparentContext())
1155 // We do not look directly into function or method contexts,
1156 // since all of the local variables and parameters of the
1157 // function/method are present within the Scope.
1158 if (Ctx->isFunctionOrMethod()) {
1159 // If we have an Objective-C instance method, look for ivars
1160 // in the corresponding interface.
1161 if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
1162 if (Method->isInstanceMethod() && Name.getAsIdentifierInfo())
1163 if (ObjCInterfaceDecl *Class = Method->getClassInterface()) {
1164 ObjCInterfaceDecl *ClassDeclared;
1165 if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(
1166 Name.getAsIdentifierInfo(),
1168 if (NamedDecl *ND = R.getAcceptableDecl(Ivar)) {
1180 // If this is a file context, we need to perform unqualified name
1181 // lookup considering using directives.
1182 if (Ctx->isFileContext()) {
1183 // If we haven't handled using directives yet, do so now.
1184 if (!VisitedUsingDirectives) {
1185 // Add using directives from this context up to the top level.
1186 for (DeclContext *UCtx = Ctx; UCtx; UCtx = UCtx->getParent()) {
1187 if (UCtx->isTransparentContext())
1190 UDirs.visit(UCtx, UCtx);
1193 // Find the innermost file scope, so we can add using directives
1194 // from local scopes.
1195 Scope *InnermostFileScope = S;
1196 while (InnermostFileScope &&
1197 !isNamespaceOrTranslationUnitScope(InnermostFileScope))
1198 InnermostFileScope = InnermostFileScope->getParent();
1199 UDirs.visitScopeChain(Initial, InnermostFileScope);
1203 VisitedUsingDirectives = true;
1206 if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs)) {
1214 // Perform qualified name lookup into this context.
1215 // FIXME: In some cases, we know that every name that could be found by
1216 // this qualified name lookup will also be on the identifier chain. For
1217 // example, inside a class without any base classes, we never need to
1218 // perform qualified lookup because all of the members are on top of the
1219 // identifier chain.
1220 if (LookupQualifiedName(R, Ctx, /*InUnqualifiedLookup=*/true))
1226 // Stop if we ran out of scopes.
1227 // FIXME: This really, really shouldn't be happening.
1228 if (!S) return false;
1230 // If we are looking for members, no need to look into global/namespace scope.
1231 if (NameKind == LookupMemberName)
1234 // Collect UsingDirectiveDecls in all scopes, and recursively all
1235 // nominated namespaces by those using-directives.
1237 // FIXME: Cache this sorted list in Scope structure, and DeclContext, so we
1238 // don't build it for each lookup!
1239 if (!VisitedUsingDirectives) {
1240 UDirs.visitScopeChain(Initial, S);
1244 // If we're not performing redeclaration lookup, do not look for local
1245 // extern declarations outside of a function scope.
1246 if (!R.isForRedeclaration())
1247 FindLocals.restore();
1249 // Lookup namespace scope, and global scope.
1250 // Unqualified name lookup in C++ requires looking into scopes
1251 // that aren't strictly lexical, and therefore we walk through the
1252 // context as well as walking through the scopes.
1253 for (; S; S = S->getParent()) {
1254 // Check whether the IdResolver has anything in this scope.
1256 for (; I != IEnd && S->isDeclScope(*I); ++I) {
1257 if (NamedDecl *ND = R.getAcceptableDecl(*I)) {
1258 // We found something. Look for anything else in our scope
1259 // with this same name and in an acceptable identifier
1260 // namespace, so that we can construct an overload set if we
1267 if (Found && S->isTemplateParamScope()) {
1272 DeclContext *Ctx = S->getEntity();
1273 if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
1274 S->getParent() && !S->getParent()->isTemplateParamScope()) {
1275 // We've just searched the last template parameter scope and
1276 // found nothing, so look into the contexts between the
1277 // lexical and semantic declaration contexts returned by
1278 // findOuterContext(). This implements the name lookup behavior
1279 // of C++ [temp.local]p8.
1280 Ctx = OutsideOfTemplateParamDC;
1281 OutsideOfTemplateParamDC = nullptr;
1285 DeclContext *OuterCtx;
1286 bool SearchAfterTemplateScope;
1287 std::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
1288 if (SearchAfterTemplateScope)
1289 OutsideOfTemplateParamDC = OuterCtx;
1291 for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
1292 // We do not directly look into transparent contexts, since
1293 // those entities will be found in the nearest enclosing
1294 // non-transparent context.
1295 if (Ctx->isTransparentContext())
1298 // If we have a context, and it's not a context stashed in the
1299 // template parameter scope for an out-of-line definition, also
1300 // look into that context.
1301 if (!(Found && S && S->isTemplateParamScope())) {
1302 assert(Ctx->isFileContext() &&
1303 "We should have been looking only at file context here already.");
1305 // Look into context considering using-directives.
1306 if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs))
1315 if (R.isForRedeclaration() && !Ctx->isTransparentContext())
1320 if (R.isForRedeclaration() && Ctx && !Ctx->isTransparentContext())
1327 /// \brief Find the declaration that a class temploid member specialization was
1328 /// instantiated from, or the member itself if it is an explicit specialization.
1329 static Decl *getInstantiatedFrom(Decl *D, MemberSpecializationInfo *MSInfo) {
1330 return MSInfo->isExplicitSpecialization() ? D : MSInfo->getInstantiatedFrom();
1333 Module *Sema::getOwningModule(Decl *Entity) {
1334 // If it's imported, grab its owning module.
1335 Module *M = Entity->getImportedOwningModule();
1336 if (M || !isa<NamedDecl>(Entity) || !cast<NamedDecl>(Entity)->isHidden())
1338 assert(!Entity->isFromASTFile() &&
1339 "hidden entity from AST file has no owning module");
1341 if (!getLangOpts().ModulesLocalVisibility) {
1342 // If we're not tracking visibility locally, the only way a declaration
1343 // can be hidden and local is if it's hidden because it's parent is (for
1344 // instance, maybe this is a lazily-declared special member of an imported
1346 auto *Parent = cast<NamedDecl>(Entity->getDeclContext());
1347 assert(Parent->isHidden() && "unexpectedly hidden decl");
1348 return getOwningModule(Parent);
1351 // It's local and hidden; grab or compute its owning module.
1352 M = Entity->getLocalOwningModule();
1356 if (auto *Containing =
1357 PP.getModuleContainingLocation(Entity->getLocation())) {
1359 } else if (Entity->isInvalidDecl() || Entity->getLocation().isInvalid()) {
1360 // Don't bother tracking visibility for invalid declarations with broken
1362 cast<NamedDecl>(Entity)->setHidden(false);
1364 // We need to assign a module to an entity that exists outside of any
1365 // module, so that we can hide it from modules that we textually enter.
1366 // Invent a fake module for all such entities.
1367 if (!CachedFakeTopLevelModule) {
1368 CachedFakeTopLevelModule =
1369 PP.getHeaderSearchInfo().getModuleMap().findOrCreateModule(
1370 "<top-level>", nullptr, false, false).first;
1372 auto &SrcMgr = PP.getSourceManager();
1373 SourceLocation StartLoc =
1374 SrcMgr.getLocForStartOfFile(SrcMgr.getMainFileID());
1376 VisibleModulesStack.empty() ? VisibleModules : VisibleModulesStack[0];
1377 TopLevel.setVisible(CachedFakeTopLevelModule, StartLoc);
1380 M = CachedFakeTopLevelModule;
1384 Entity->setLocalOwningModule(M);
1388 void Sema::makeMergedDefinitionVisible(NamedDecl *ND, SourceLocation Loc) {
1389 if (auto *M = PP.getModuleContainingLocation(Loc))
1390 Context.mergeDefinitionIntoModule(ND, M);
1392 // We're not building a module; just make the definition visible.
1393 ND->setHidden(false);
1395 // If ND is a template declaration, make the template parameters
1396 // visible too. They're not (necessarily) within a mergeable DeclContext.
1397 if (auto *TD = dyn_cast<TemplateDecl>(ND))
1398 for (auto *Param : *TD->getTemplateParameters())
1399 makeMergedDefinitionVisible(Param, Loc);
1402 /// \brief Find the module in which the given declaration was defined.
1403 static Module *getDefiningModule(Sema &S, Decl *Entity) {
1404 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Entity)) {
1405 // If this function was instantiated from a template, the defining module is
1406 // the module containing the pattern.
1407 if (FunctionDecl *Pattern = FD->getTemplateInstantiationPattern())
1409 } else if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Entity)) {
1410 if (CXXRecordDecl *Pattern = RD->getTemplateInstantiationPattern())
1412 } else if (EnumDecl *ED = dyn_cast<EnumDecl>(Entity)) {
1413 if (MemberSpecializationInfo *MSInfo = ED->getMemberSpecializationInfo())
1414 Entity = getInstantiatedFrom(ED, MSInfo);
1415 } else if (VarDecl *VD = dyn_cast<VarDecl>(Entity)) {
1416 // FIXME: Map from variable template specializations back to the template.
1417 if (MemberSpecializationInfo *MSInfo = VD->getMemberSpecializationInfo())
1418 Entity = getInstantiatedFrom(VD, MSInfo);
1421 // Walk up to the containing context. That might also have been instantiated
1423 DeclContext *Context = Entity->getDeclContext();
1424 if (Context->isFileContext())
1425 return S.getOwningModule(Entity);
1426 return getDefiningModule(S, cast<Decl>(Context));
1429 llvm::DenseSet<Module*> &Sema::getLookupModules() {
1430 unsigned N = ActiveTemplateInstantiations.size();
1431 for (unsigned I = ActiveTemplateInstantiationLookupModules.size();
1434 getDefiningModule(*this, ActiveTemplateInstantiations[I].Entity);
1435 if (M && !LookupModulesCache.insert(M).second)
1437 ActiveTemplateInstantiationLookupModules.push_back(M);
1439 return LookupModulesCache;
1442 bool Sema::hasVisibleMergedDefinition(NamedDecl *Def) {
1443 for (Module *Merged : Context.getModulesWithMergedDefinition(Def))
1444 if (isModuleVisible(Merged))
1449 template<typename ParmDecl>
1451 hasVisibleDefaultArgument(Sema &S, const ParmDecl *D,
1452 llvm::SmallVectorImpl<Module *> *Modules) {
1453 if (!D->hasDefaultArgument())
1457 auto &DefaultArg = D->getDefaultArgStorage();
1458 if (!DefaultArg.isInherited() && S.isVisible(D))
1461 if (!DefaultArg.isInherited() && Modules) {
1462 auto *NonConstD = const_cast<ParmDecl*>(D);
1463 Modules->push_back(S.getOwningModule(NonConstD));
1464 const auto &Merged = S.Context.getModulesWithMergedDefinition(NonConstD);
1465 Modules->insert(Modules->end(), Merged.begin(), Merged.end());
1468 // If there was a previous default argument, maybe its parameter is visible.
1469 D = DefaultArg.getInheritedFrom();
1474 bool Sema::hasVisibleDefaultArgument(const NamedDecl *D,
1475 llvm::SmallVectorImpl<Module *> *Modules) {
1476 if (auto *P = dyn_cast<TemplateTypeParmDecl>(D))
1477 return ::hasVisibleDefaultArgument(*this, P, Modules);
1478 if (auto *P = dyn_cast<NonTypeTemplateParmDecl>(D))
1479 return ::hasVisibleDefaultArgument(*this, P, Modules);
1480 return ::hasVisibleDefaultArgument(*this, cast<TemplateTemplateParmDecl>(D),
1484 bool Sema::hasVisibleMemberSpecialization(
1485 const NamedDecl *D, llvm::SmallVectorImpl<Module *> *Modules) {
1486 assert(isa<CXXRecordDecl>(D->getDeclContext()) &&
1487 "not a member specialization");
1488 for (auto *Redecl : D->redecls()) {
1489 // If the specialization is declared at namespace scope, then it's a member
1490 // specialization declaration. If it's lexically inside the class
1491 // definition then it was instantiated.
1493 // FIXME: This is a hack. There should be a better way to determine this.
1494 // FIXME: What about MS-style explicit specializations declared within a
1495 // class definition?
1496 if (Redecl->getLexicalDeclContext()->isFileContext()) {
1497 auto *NonConstR = const_cast<NamedDecl*>(cast<NamedDecl>(Redecl));
1499 if (isVisible(NonConstR))
1503 Modules->push_back(getOwningModule(NonConstR));
1504 const auto &Merged = Context.getModulesWithMergedDefinition(NonConstR);
1505 Modules->insert(Modules->end(), Merged.begin(), Merged.end());
1513 /// \brief Determine whether a declaration is visible to name lookup.
1515 /// This routine determines whether the declaration D is visible in the current
1516 /// lookup context, taking into account the current template instantiation
1517 /// stack. During template instantiation, a declaration is visible if it is
1518 /// visible from a module containing any entity on the template instantiation
1519 /// path (by instantiating a template, you allow it to see the declarations that
1520 /// your module can see, including those later on in your module).
1521 bool LookupResult::isVisibleSlow(Sema &SemaRef, NamedDecl *D) {
1522 assert(D->isHidden() && "should not call this: not in slow case");
1523 Module *DeclModule = nullptr;
1525 if (SemaRef.getLangOpts().ModulesLocalVisibility) {
1526 DeclModule = SemaRef.getOwningModule(D);
1528 // getOwningModule() may have decided the declaration should not be hidden.
1529 assert(!D->isHidden() && "hidden decl not from a module");
1533 // If the owning module is visible, and the decl is not module private,
1534 // then the decl is visible too. (Module private is ignored within the same
1535 // top-level module.)
1536 if ((!D->isFromASTFile() || !D->isModulePrivate()) &&
1537 (SemaRef.isModuleVisible(DeclModule) ||
1538 SemaRef.hasVisibleMergedDefinition(D)))
1542 // If this declaration is not at namespace scope nor module-private,
1543 // then it is visible if its lexical parent has a visible definition.
1544 DeclContext *DC = D->getLexicalDeclContext();
1545 if (!D->isModulePrivate() &&
1546 DC && !DC->isFileContext() && !isa<LinkageSpecDecl>(DC)) {
1547 // For a parameter, check whether our current template declaration's
1548 // lexical context is visible, not whether there's some other visible
1549 // definition of it, because parameters aren't "within" the definition.
1550 if ((D->isTemplateParameter() || isa<ParmVarDecl>(D))
1551 ? isVisible(SemaRef, cast<NamedDecl>(DC))
1552 : SemaRef.hasVisibleDefinition(cast<NamedDecl>(DC))) {
1553 if (SemaRef.ActiveTemplateInstantiations.empty() &&
1554 // FIXME: Do something better in this case.
1555 !SemaRef.getLangOpts().ModulesLocalVisibility) {
1556 // Cache the fact that this declaration is implicitly visible because
1557 // its parent has a visible definition.
1558 D->setHidden(false);
1565 // Find the extra places where we need to look.
1566 llvm::DenseSet<Module*> &LookupModules = SemaRef.getLookupModules();
1567 if (LookupModules.empty())
1571 DeclModule = SemaRef.getOwningModule(D);
1572 assert(DeclModule && "hidden decl not from a module");
1575 // If our lookup set contains the decl's module, it's visible.
1576 if (LookupModules.count(DeclModule))
1579 // If the declaration isn't exported, it's not visible in any other module.
1580 if (D->isModulePrivate())
1583 // Check whether DeclModule is transitively exported to an import of
1585 return std::any_of(LookupModules.begin(), LookupModules.end(),
1586 [&](Module *M) { return M->isModuleVisible(DeclModule); });
1589 bool Sema::isVisibleSlow(const NamedDecl *D) {
1590 return LookupResult::isVisible(*this, const_cast<NamedDecl*>(D));
1593 bool Sema::shouldLinkPossiblyHiddenDecl(LookupResult &R, const NamedDecl *New) {
1598 return New->isExternallyVisible();
1601 /// \brief Retrieve the visible declaration corresponding to D, if any.
1603 /// This routine determines whether the declaration D is visible in the current
1604 /// module, with the current imports. If not, it checks whether any
1605 /// redeclaration of D is visible, and if so, returns that declaration.
1607 /// \returns D, or a visible previous declaration of D, whichever is more recent
1608 /// and visible. If no declaration of D is visible, returns null.
1609 static NamedDecl *findAcceptableDecl(Sema &SemaRef, NamedDecl *D) {
1610 assert(!LookupResult::isVisible(SemaRef, D) && "not in slow case");
1612 for (auto RD : D->redecls()) {
1613 // Don't bother with extra checks if we already know this one isn't visible.
1617 auto ND = cast<NamedDecl>(RD);
1618 // FIXME: This is wrong in the case where the previous declaration is not
1619 // visible in the same scope as D. This needs to be done much more
1621 if (LookupResult::isVisible(SemaRef, ND))
1628 bool Sema::hasVisibleDeclarationSlow(const NamedDecl *D,
1629 llvm::SmallVectorImpl<Module *> *Modules) {
1630 assert(!isVisible(D) && "not in slow case");
1632 for (auto *Redecl : D->redecls()) {
1633 auto *NonConstR = const_cast<NamedDecl*>(cast<NamedDecl>(Redecl));
1634 if (isVisible(NonConstR))
1638 Modules->push_back(getOwningModule(NonConstR));
1639 const auto &Merged = Context.getModulesWithMergedDefinition(NonConstR);
1640 Modules->insert(Modules->end(), Merged.begin(), Merged.end());
1647 NamedDecl *LookupResult::getAcceptableDeclSlow(NamedDecl *D) const {
1648 if (auto *ND = dyn_cast<NamespaceDecl>(D)) {
1649 // Namespaces are a bit of a special case: we expect there to be a lot of
1650 // redeclarations of some namespaces, all declarations of a namespace are
1651 // essentially interchangeable, all declarations are found by name lookup
1652 // if any is, and namespaces are never looked up during template
1653 // instantiation. So we benefit from caching the check in this case, and
1654 // it is correct to do so.
1655 auto *Key = ND->getCanonicalDecl();
1656 if (auto *Acceptable = getSema().VisibleNamespaceCache.lookup(Key))
1659 isVisible(getSema(), Key) ? Key : findAcceptableDecl(getSema(), Key);
1661 getSema().VisibleNamespaceCache.insert(std::make_pair(Key, Acceptable));
1665 return findAcceptableDecl(getSema(), D);
1668 /// @brief Perform unqualified name lookup starting from a given
1671 /// Unqualified name lookup (C++ [basic.lookup.unqual], C99 6.2.1) is
1672 /// used to find names within the current scope. For example, 'x' in
1676 /// return x; // unqualified name look finds 'x' in the global scope
1680 /// Different lookup criteria can find different names. For example, a
1681 /// particular scope can have both a struct and a function of the same
1682 /// name, and each can be found by certain lookup criteria. For more
1683 /// information about lookup criteria, see the documentation for the
1684 /// class LookupCriteria.
1686 /// @param S The scope from which unqualified name lookup will
1687 /// begin. If the lookup criteria permits, name lookup may also search
1688 /// in the parent scopes.
1690 /// @param [in,out] R Specifies the lookup to perform (e.g., the name to
1691 /// look up and the lookup kind), and is updated with the results of lookup
1692 /// including zero or more declarations and possibly additional information
1693 /// used to diagnose ambiguities.
1695 /// @returns \c true if lookup succeeded and false otherwise.
1696 bool Sema::LookupName(LookupResult &R, Scope *S, bool AllowBuiltinCreation) {
1697 DeclarationName Name = R.getLookupName();
1698 if (!Name) return false;
1700 LookupNameKind NameKind = R.getLookupKind();
1702 if (!getLangOpts().CPlusPlus) {
1703 // Unqualified name lookup in C/Objective-C is purely lexical, so
1704 // search in the declarations attached to the name.
1705 if (NameKind == Sema::LookupRedeclarationWithLinkage) {
1706 // Find the nearest non-transparent declaration scope.
1707 while (!(S->getFlags() & Scope::DeclScope) ||
1708 (S->getEntity() && S->getEntity()->isTransparentContext()))
1712 // When performing a scope lookup, we want to find local extern decls.
1713 FindLocalExternScope FindLocals(R);
1715 // Scan up the scope chain looking for a decl that matches this
1716 // identifier that is in the appropriate namespace. This search
1717 // should not take long, as shadowing of names is uncommon, and
1718 // deep shadowing is extremely uncommon.
1719 bool LeftStartingScope = false;
1721 for (IdentifierResolver::iterator I = IdResolver.begin(Name),
1722 IEnd = IdResolver.end();
1724 if (NamedDecl *D = R.getAcceptableDecl(*I)) {
1725 if (NameKind == LookupRedeclarationWithLinkage) {
1726 // Determine whether this (or a previous) declaration is
1728 if (!LeftStartingScope && !S->isDeclScope(*I))
1729 LeftStartingScope = true;
1731 // If we found something outside of our starting scope that
1732 // does not have linkage, skip it.
1733 if (LeftStartingScope && !((*I)->hasLinkage())) {
1738 else if (NameKind == LookupObjCImplicitSelfParam &&
1739 !isa<ImplicitParamDecl>(*I))
1744 // Check whether there are any other declarations with the same name
1745 // and in the same scope.
1747 // Find the scope in which this declaration was declared (if it
1748 // actually exists in a Scope).
1749 while (S && !S->isDeclScope(D))
1752 // If the scope containing the declaration is the translation unit,
1753 // then we'll need to perform our checks based on the matching
1754 // DeclContexts rather than matching scopes.
1755 if (S && isNamespaceOrTranslationUnitScope(S))
1758 // Compute the DeclContext, if we need it.
1759 DeclContext *DC = nullptr;
1761 DC = (*I)->getDeclContext()->getRedeclContext();
1763 IdentifierResolver::iterator LastI = I;
1764 for (++LastI; LastI != IEnd; ++LastI) {
1766 // Match based on scope.
1767 if (!S->isDeclScope(*LastI))
1770 // Match based on DeclContext.
1772 = (*LastI)->getDeclContext()->getRedeclContext();
1773 if (!LastDC->Equals(DC))
1777 // If the declaration is in the right namespace and visible, add it.
1778 if (NamedDecl *LastD = R.getAcceptableDecl(*LastI))
1788 // Perform C++ unqualified name lookup.
1789 if (CppLookupName(R, S))
1793 // If we didn't find a use of this identifier, and if the identifier
1794 // corresponds to a compiler builtin, create the decl object for the builtin
1795 // now, injecting it into translation unit scope, and return it.
1796 if (AllowBuiltinCreation && LookupBuiltin(*this, R))
1799 // If we didn't find a use of this identifier, the ExternalSource
1800 // may be able to handle the situation.
1801 // Note: some lookup failures are expected!
1802 // See e.g. R.isForRedeclaration().
1803 return (ExternalSource && ExternalSource->LookupUnqualified(R, S));
1806 /// @brief Perform qualified name lookup in the namespaces nominated by
1807 /// using directives by the given context.
1809 /// C++98 [namespace.qual]p2:
1810 /// Given X::m (where X is a user-declared namespace), or given \::m
1811 /// (where X is the global namespace), let S be the set of all
1812 /// declarations of m in X and in the transitive closure of all
1813 /// namespaces nominated by using-directives in X and its used
1814 /// namespaces, except that using-directives are ignored in any
1815 /// namespace, including X, directly containing one or more
1816 /// declarations of m. No namespace is searched more than once in
1817 /// the lookup of a name. If S is the empty set, the program is
1818 /// ill-formed. Otherwise, if S has exactly one member, or if the
1819 /// context of the reference is a using-declaration
1820 /// (namespace.udecl), S is the required set of declarations of
1821 /// m. Otherwise if the use of m is not one that allows a unique
1822 /// declaration to be chosen from S, the program is ill-formed.
1824 /// C++98 [namespace.qual]p5:
1825 /// During the lookup of a qualified namespace member name, if the
1826 /// lookup finds more than one declaration of the member, and if one
1827 /// declaration introduces a class name or enumeration name and the
1828 /// other declarations either introduce the same object, the same
1829 /// enumerator or a set of functions, the non-type name hides the
1830 /// class or enumeration name if and only if the declarations are
1831 /// from the same namespace; otherwise (the declarations are from
1832 /// different namespaces), the program is ill-formed.
1833 static bool LookupQualifiedNameInUsingDirectives(Sema &S, LookupResult &R,
1834 DeclContext *StartDC) {
1835 assert(StartDC->isFileContext() && "start context is not a file context");
1837 DeclContext::udir_range UsingDirectives = StartDC->using_directives();
1838 if (UsingDirectives.begin() == UsingDirectives.end()) return false;
1840 // We have at least added all these contexts to the queue.
1841 llvm::SmallPtrSet<DeclContext*, 8> Visited;
1842 Visited.insert(StartDC);
1844 // We have not yet looked into these namespaces, much less added
1845 // their "using-children" to the queue.
1846 SmallVector<NamespaceDecl*, 8> Queue;
1848 // We have already looked into the initial namespace; seed the queue
1849 // with its using-children.
1850 for (auto *I : UsingDirectives) {
1851 NamespaceDecl *ND = I->getNominatedNamespace()->getOriginalNamespace();
1852 if (Visited.insert(ND).second)
1853 Queue.push_back(ND);
1856 // The easiest way to implement the restriction in [namespace.qual]p5
1857 // is to check whether any of the individual results found a tag
1858 // and, if so, to declare an ambiguity if the final result is not
1860 bool FoundTag = false;
1861 bool FoundNonTag = false;
1863 LookupResult LocalR(LookupResult::Temporary, R);
1866 while (!Queue.empty()) {
1867 NamespaceDecl *ND = Queue.pop_back_val();
1869 // We go through some convolutions here to avoid copying results
1870 // between LookupResults.
1871 bool UseLocal = !R.empty();
1872 LookupResult &DirectR = UseLocal ? LocalR : R;
1873 bool FoundDirect = LookupDirect(S, DirectR, ND);
1876 // First do any local hiding.
1877 DirectR.resolveKind();
1879 // If the local result is a tag, remember that.
1880 if (DirectR.isSingleTagDecl())
1885 // Append the local results to the total results if necessary.
1887 R.addAllDecls(LocalR);
1892 // If we find names in this namespace, ignore its using directives.
1898 for (auto I : ND->using_directives()) {
1899 NamespaceDecl *Nom = I->getNominatedNamespace();
1900 if (Visited.insert(Nom).second)
1901 Queue.push_back(Nom);
1906 if (FoundTag && FoundNonTag)
1907 R.setAmbiguousQualifiedTagHiding();
1915 /// \brief Callback that looks for any member of a class with the given name.
1916 static bool LookupAnyMember(const CXXBaseSpecifier *Specifier,
1917 CXXBasePath &Path, DeclarationName Name) {
1918 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl();
1920 Path.Decls = BaseRecord->lookup(Name);
1921 return !Path.Decls.empty();
1924 /// \brief Determine whether the given set of member declarations contains only
1925 /// static members, nested types, and enumerators.
1926 template<typename InputIterator>
1927 static bool HasOnlyStaticMembers(InputIterator First, InputIterator Last) {
1928 Decl *D = (*First)->getUnderlyingDecl();
1929 if (isa<VarDecl>(D) || isa<TypeDecl>(D) || isa<EnumConstantDecl>(D))
1932 if (isa<CXXMethodDecl>(D)) {
1933 // Determine whether all of the methods are static.
1934 bool AllMethodsAreStatic = true;
1935 for(; First != Last; ++First) {
1936 D = (*First)->getUnderlyingDecl();
1938 if (!isa<CXXMethodDecl>(D)) {
1939 assert(isa<TagDecl>(D) && "Non-function must be a tag decl");
1943 if (!cast<CXXMethodDecl>(D)->isStatic()) {
1944 AllMethodsAreStatic = false;
1949 if (AllMethodsAreStatic)
1956 /// \brief Perform qualified name lookup into a given context.
1958 /// Qualified name lookup (C++ [basic.lookup.qual]) is used to find
1959 /// names when the context of those names is explicit specified, e.g.,
1960 /// "std::vector" or "x->member", or as part of unqualified name lookup.
1962 /// Different lookup criteria can find different names. For example, a
1963 /// particular scope can have both a struct and a function of the same
1964 /// name, and each can be found by certain lookup criteria. For more
1965 /// information about lookup criteria, see the documentation for the
1966 /// class LookupCriteria.
1968 /// \param R captures both the lookup criteria and any lookup results found.
1970 /// \param LookupCtx The context in which qualified name lookup will
1971 /// search. If the lookup criteria permits, name lookup may also search
1972 /// in the parent contexts or (for C++ classes) base classes.
1974 /// \param InUnqualifiedLookup true if this is qualified name lookup that
1975 /// occurs as part of unqualified name lookup.
1977 /// \returns true if lookup succeeded, false if it failed.
1978 bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
1979 bool InUnqualifiedLookup) {
1980 assert(LookupCtx && "Sema::LookupQualifiedName requires a lookup context");
1982 if (!R.getLookupName())
1985 // Make sure that the declaration context is complete.
1986 assert((!isa<TagDecl>(LookupCtx) ||
1987 LookupCtx->isDependentContext() ||
1988 cast<TagDecl>(LookupCtx)->isCompleteDefinition() ||
1989 cast<TagDecl>(LookupCtx)->isBeingDefined()) &&
1990 "Declaration context must already be complete!");
1992 struct QualifiedLookupInScope {
1994 DeclContext *Context;
1995 // Set flag in DeclContext informing debugger that we're looking for qualified name
1996 QualifiedLookupInScope(DeclContext *ctx) : Context(ctx) {
1997 oldVal = ctx->setUseQualifiedLookup();
1999 ~QualifiedLookupInScope() {
2000 Context->setUseQualifiedLookup(oldVal);
2004 if (LookupDirect(*this, R, LookupCtx)) {
2006 if (isa<CXXRecordDecl>(LookupCtx))
2007 R.setNamingClass(cast<CXXRecordDecl>(LookupCtx));
2011 // Don't descend into implied contexts for redeclarations.
2012 // C++98 [namespace.qual]p6:
2013 // In a declaration for a namespace member in which the
2014 // declarator-id is a qualified-id, given that the qualified-id
2015 // for the namespace member has the form
2016 // nested-name-specifier unqualified-id
2017 // the unqualified-id shall name a member of the namespace
2018 // designated by the nested-name-specifier.
2019 // See also [class.mfct]p5 and [class.static.data]p2.
2020 if (R.isForRedeclaration())
2023 // If this is a namespace, look it up in the implied namespaces.
2024 if (LookupCtx->isFileContext())
2025 return LookupQualifiedNameInUsingDirectives(*this, R, LookupCtx);
2027 // If this isn't a C++ class, we aren't allowed to look into base
2028 // classes, we're done.
2029 CXXRecordDecl *LookupRec = dyn_cast<CXXRecordDecl>(LookupCtx);
2030 if (!LookupRec || !LookupRec->getDefinition())
2033 // If we're performing qualified name lookup into a dependent class,
2034 // then we are actually looking into a current instantiation. If we have any
2035 // dependent base classes, then we either have to delay lookup until
2036 // template instantiation time (at which point all bases will be available)
2037 // or we have to fail.
2038 if (!InUnqualifiedLookup && LookupRec->isDependentContext() &&
2039 LookupRec->hasAnyDependentBases()) {
2040 R.setNotFoundInCurrentInstantiation();
2044 // Perform lookup into our base classes.
2046 Paths.setOrigin(LookupRec);
2048 // Look for this member in our base classes
2049 bool (*BaseCallback)(const CXXBaseSpecifier *Specifier, CXXBasePath &Path,
2050 DeclarationName Name) = nullptr;
2051 switch (R.getLookupKind()) {
2052 case LookupObjCImplicitSelfParam:
2053 case LookupOrdinaryName:
2054 case LookupMemberName:
2055 case LookupRedeclarationWithLinkage:
2056 case LookupLocalFriendName:
2057 BaseCallback = &CXXRecordDecl::FindOrdinaryMember;
2061 BaseCallback = &CXXRecordDecl::FindTagMember;
2065 BaseCallback = &LookupAnyMember;
2068 case LookupOMPReductionName:
2069 BaseCallback = &CXXRecordDecl::FindOMPReductionMember;
2072 case LookupUsingDeclName:
2073 // This lookup is for redeclarations only.
2075 case LookupOperatorName:
2076 case LookupNamespaceName:
2077 case LookupObjCProtocolName:
2079 // These lookups will never find a member in a C++ class (or base class).
2082 case LookupNestedNameSpecifierName:
2083 BaseCallback = &CXXRecordDecl::FindNestedNameSpecifierMember;
2087 DeclarationName Name = R.getLookupName();
2088 if (!LookupRec->lookupInBases(
2089 [=](const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
2090 return BaseCallback(Specifier, Path, Name);
2095 R.setNamingClass(LookupRec);
2097 // C++ [class.member.lookup]p2:
2098 // [...] If the resulting set of declarations are not all from
2099 // sub-objects of the same type, or the set has a nonstatic member
2100 // and includes members from distinct sub-objects, there is an
2101 // ambiguity and the program is ill-formed. Otherwise that set is
2102 // the result of the lookup.
2103 QualType SubobjectType;
2104 int SubobjectNumber = 0;
2105 AccessSpecifier SubobjectAccess = AS_none;
2107 for (CXXBasePaths::paths_iterator Path = Paths.begin(), PathEnd = Paths.end();
2108 Path != PathEnd; ++Path) {
2109 const CXXBasePathElement &PathElement = Path->back();
2111 // Pick the best (i.e. most permissive i.e. numerically lowest) access
2112 // across all paths.
2113 SubobjectAccess = std::min(SubobjectAccess, Path->Access);
2115 // Determine whether we're looking at a distinct sub-object or not.
2116 if (SubobjectType.isNull()) {
2117 // This is the first subobject we've looked at. Record its type.
2118 SubobjectType = Context.getCanonicalType(PathElement.Base->getType());
2119 SubobjectNumber = PathElement.SubobjectNumber;
2124 != Context.getCanonicalType(PathElement.Base->getType())) {
2125 // We found members of the given name in two subobjects of
2126 // different types. If the declaration sets aren't the same, this
2127 // lookup is ambiguous.
2128 if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end())) {
2129 CXXBasePaths::paths_iterator FirstPath = Paths.begin();
2130 DeclContext::lookup_iterator FirstD = FirstPath->Decls.begin();
2131 DeclContext::lookup_iterator CurrentD = Path->Decls.begin();
2133 while (FirstD != FirstPath->Decls.end() &&
2134 CurrentD != Path->Decls.end()) {
2135 if ((*FirstD)->getUnderlyingDecl()->getCanonicalDecl() !=
2136 (*CurrentD)->getUnderlyingDecl()->getCanonicalDecl())
2143 if (FirstD == FirstPath->Decls.end() &&
2144 CurrentD == Path->Decls.end())
2148 R.setAmbiguousBaseSubobjectTypes(Paths);
2152 if (SubobjectNumber != PathElement.SubobjectNumber) {
2153 // We have a different subobject of the same type.
2155 // C++ [class.member.lookup]p5:
2156 // A static member, a nested type or an enumerator defined in
2157 // a base class T can unambiguously be found even if an object
2158 // has more than one base class subobject of type T.
2159 if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end()))
2162 // We have found a nonstatic member name in multiple, distinct
2163 // subobjects. Name lookup is ambiguous.
2164 R.setAmbiguousBaseSubobjects(Paths);
2169 // Lookup in a base class succeeded; return these results.
2171 for (auto *D : Paths.front().Decls) {
2172 AccessSpecifier AS = CXXRecordDecl::MergeAccess(SubobjectAccess,
2180 /// \brief Performs qualified name lookup or special type of lookup for
2181 /// "__super::" scope specifier.
2183 /// This routine is a convenience overload meant to be called from contexts
2184 /// that need to perform a qualified name lookup with an optional C++ scope
2185 /// specifier that might require special kind of lookup.
2187 /// \param R captures both the lookup criteria and any lookup results found.
2189 /// \param LookupCtx The context in which qualified name lookup will
2192 /// \param SS An optional C++ scope-specifier.
2194 /// \returns true if lookup succeeded, false if it failed.
2195 bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
2197 auto *NNS = SS.getScopeRep();
2198 if (NNS && NNS->getKind() == NestedNameSpecifier::Super)
2199 return LookupInSuper(R, NNS->getAsRecordDecl());
2202 return LookupQualifiedName(R, LookupCtx);
2205 /// @brief Performs name lookup for a name that was parsed in the
2206 /// source code, and may contain a C++ scope specifier.
2208 /// This routine is a convenience routine meant to be called from
2209 /// contexts that receive a name and an optional C++ scope specifier
2210 /// (e.g., "N::M::x"). It will then perform either qualified or
2211 /// unqualified name lookup (with LookupQualifiedName or LookupName,
2212 /// respectively) on the given name and return those results. It will
2213 /// perform a special type of lookup for "__super::" scope specifier.
2215 /// @param S The scope from which unqualified name lookup will
2218 /// @param SS An optional C++ scope-specifier, e.g., "::N::M".
2220 /// @param EnteringContext Indicates whether we are going to enter the
2221 /// context of the scope-specifier SS (if present).
2223 /// @returns True if any decls were found (but possibly ambiguous)
2224 bool Sema::LookupParsedName(LookupResult &R, Scope *S, CXXScopeSpec *SS,
2225 bool AllowBuiltinCreation, bool EnteringContext) {
2226 if (SS && SS->isInvalid()) {
2227 // When the scope specifier is invalid, don't even look for
2232 if (SS && SS->isSet()) {
2233 NestedNameSpecifier *NNS = SS->getScopeRep();
2234 if (NNS->getKind() == NestedNameSpecifier::Super)
2235 return LookupInSuper(R, NNS->getAsRecordDecl());
2237 if (DeclContext *DC = computeDeclContext(*SS, EnteringContext)) {
2238 // We have resolved the scope specifier to a particular declaration
2239 // contex, and will perform name lookup in that context.
2240 if (!DC->isDependentContext() && RequireCompleteDeclContext(*SS, DC))
2243 R.setContextRange(SS->getRange());
2244 return LookupQualifiedName(R, DC);
2247 // We could not resolve the scope specified to a specific declaration
2248 // context, which means that SS refers to an unknown specialization.
2249 // Name lookup can't find anything in this case.
2250 R.setNotFoundInCurrentInstantiation();
2251 R.setContextRange(SS->getRange());
2255 // Perform unqualified name lookup starting in the given scope.
2256 return LookupName(R, S, AllowBuiltinCreation);
2259 /// \brief Perform qualified name lookup into all base classes of the given
2262 /// \param R captures both the lookup criteria and any lookup results found.
2264 /// \param Class The context in which qualified name lookup will
2265 /// search. Name lookup will search in all base classes merging the results.
2267 /// @returns True if any decls were found (but possibly ambiguous)
2268 bool Sema::LookupInSuper(LookupResult &R, CXXRecordDecl *Class) {
2269 // The access-control rules we use here are essentially the rules for
2270 // doing a lookup in Class that just magically skipped the direct
2271 // members of Class itself. That is, the naming class is Class, and the
2272 // access includes the access of the base.
2273 for (const auto &BaseSpec : Class->bases()) {
2274 CXXRecordDecl *RD = cast<CXXRecordDecl>(
2275 BaseSpec.getType()->castAs<RecordType>()->getDecl());
2276 LookupResult Result(*this, R.getLookupNameInfo(), R.getLookupKind());
2277 Result.setBaseObjectType(Context.getRecordType(Class));
2278 LookupQualifiedName(Result, RD);
2280 // Copy the lookup results into the target, merging the base's access into
2282 for (auto I = Result.begin(), E = Result.end(); I != E; ++I) {
2283 R.addDecl(I.getDecl(),
2284 CXXRecordDecl::MergeAccess(BaseSpec.getAccessSpecifier(),
2288 Result.suppressDiagnostics();
2292 R.setNamingClass(Class);
2297 /// \brief Produce a diagnostic describing the ambiguity that resulted
2298 /// from name lookup.
2300 /// \param Result The result of the ambiguous lookup to be diagnosed.
2301 void Sema::DiagnoseAmbiguousLookup(LookupResult &Result) {
2302 assert(Result.isAmbiguous() && "Lookup result must be ambiguous");
2304 DeclarationName Name = Result.getLookupName();
2305 SourceLocation NameLoc = Result.getNameLoc();
2306 SourceRange LookupRange = Result.getContextRange();
2308 switch (Result.getAmbiguityKind()) {
2309 case LookupResult::AmbiguousBaseSubobjects: {
2310 CXXBasePaths *Paths = Result.getBasePaths();
2311 QualType SubobjectType = Paths->front().back().Base->getType();
2312 Diag(NameLoc, diag::err_ambiguous_member_multiple_subobjects)
2313 << Name << SubobjectType << getAmbiguousPathsDisplayString(*Paths)
2316 DeclContext::lookup_iterator Found = Paths->front().Decls.begin();
2317 while (isa<CXXMethodDecl>(*Found) &&
2318 cast<CXXMethodDecl>(*Found)->isStatic())
2321 Diag((*Found)->getLocation(), diag::note_ambiguous_member_found);
2325 case LookupResult::AmbiguousBaseSubobjectTypes: {
2326 Diag(NameLoc, diag::err_ambiguous_member_multiple_subobject_types)
2327 << Name << LookupRange;
2329 CXXBasePaths *Paths = Result.getBasePaths();
2330 std::set<Decl *> DeclsPrinted;
2331 for (CXXBasePaths::paths_iterator Path = Paths->begin(),
2332 PathEnd = Paths->end();
2333 Path != PathEnd; ++Path) {
2334 Decl *D = Path->Decls.front();
2335 if (DeclsPrinted.insert(D).second)
2336 Diag(D->getLocation(), diag::note_ambiguous_member_found);
2341 case LookupResult::AmbiguousTagHiding: {
2342 Diag(NameLoc, diag::err_ambiguous_tag_hiding) << Name << LookupRange;
2344 llvm::SmallPtrSet<NamedDecl*, 8> TagDecls;
2346 for (auto *D : Result)
2347 if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
2348 TagDecls.insert(TD);
2349 Diag(TD->getLocation(), diag::note_hidden_tag);
2352 for (auto *D : Result)
2353 if (!isa<TagDecl>(D))
2354 Diag(D->getLocation(), diag::note_hiding_object);
2356 // For recovery purposes, go ahead and implement the hiding.
2357 LookupResult::Filter F = Result.makeFilter();
2358 while (F.hasNext()) {
2359 if (TagDecls.count(F.next()))
2366 case LookupResult::AmbiguousReference: {
2367 Diag(NameLoc, diag::err_ambiguous_reference) << Name << LookupRange;
2369 for (auto *D : Result)
2370 Diag(D->getLocation(), diag::note_ambiguous_candidate) << D;
2377 struct AssociatedLookup {
2378 AssociatedLookup(Sema &S, SourceLocation InstantiationLoc,
2379 Sema::AssociatedNamespaceSet &Namespaces,
2380 Sema::AssociatedClassSet &Classes)
2381 : S(S), Namespaces(Namespaces), Classes(Classes),
2382 InstantiationLoc(InstantiationLoc) {
2386 Sema::AssociatedNamespaceSet &Namespaces;
2387 Sema::AssociatedClassSet &Classes;
2388 SourceLocation InstantiationLoc;
2390 } // end anonymous namespace
2393 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType T);
2395 static void CollectEnclosingNamespace(Sema::AssociatedNamespaceSet &Namespaces,
2397 // Add the associated namespace for this class.
2399 // We don't use DeclContext::getEnclosingNamespaceContext() as this may
2400 // be a locally scoped record.
2402 // We skip out of inline namespaces. The innermost non-inline namespace
2403 // contains all names of all its nested inline namespaces anyway, so we can
2404 // replace the entire inline namespace tree with its root.
2405 while (Ctx->isRecord() || Ctx->isTransparentContext() ||
2406 Ctx->isInlineNamespace())
2407 Ctx = Ctx->getParent();
2409 if (Ctx->isFileContext())
2410 Namespaces.insert(Ctx->getPrimaryContext());
2413 // \brief Add the associated classes and namespaces for argument-dependent
2414 // lookup that involves a template argument (C++ [basic.lookup.koenig]p2).
2416 addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
2417 const TemplateArgument &Arg) {
2418 // C++ [basic.lookup.koenig]p2, last bullet:
2420 switch (Arg.getKind()) {
2421 case TemplateArgument::Null:
2424 case TemplateArgument::Type:
2425 // [...] the namespaces and classes associated with the types of the
2426 // template arguments provided for template type parameters (excluding
2427 // template template parameters)
2428 addAssociatedClassesAndNamespaces(Result, Arg.getAsType());
2431 case TemplateArgument::Template:
2432 case TemplateArgument::TemplateExpansion: {
2433 // [...] the namespaces in which any template template arguments are
2434 // defined; and the classes in which any member templates used as
2435 // template template arguments are defined.
2436 TemplateName Template = Arg.getAsTemplateOrTemplatePattern();
2437 if (ClassTemplateDecl *ClassTemplate
2438 = dyn_cast<ClassTemplateDecl>(Template.getAsTemplateDecl())) {
2439 DeclContext *Ctx = ClassTemplate->getDeclContext();
2440 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2441 Result.Classes.insert(EnclosingClass);
2442 // Add the associated namespace for this class.
2443 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2448 case TemplateArgument::Declaration:
2449 case TemplateArgument::Integral:
2450 case TemplateArgument::Expression:
2451 case TemplateArgument::NullPtr:
2452 // [Note: non-type template arguments do not contribute to the set of
2453 // associated namespaces. ]
2456 case TemplateArgument::Pack:
2457 for (const auto &P : Arg.pack_elements())
2458 addAssociatedClassesAndNamespaces(Result, P);
2463 // \brief Add the associated classes and namespaces for
2464 // argument-dependent lookup with an argument of class type
2465 // (C++ [basic.lookup.koenig]p2).
2467 addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
2468 CXXRecordDecl *Class) {
2470 // Just silently ignore anything whose name is __va_list_tag.
2471 if (Class->getDeclName() == Result.S.VAListTagName)
2474 // C++ [basic.lookup.koenig]p2:
2476 // -- If T is a class type (including unions), its associated
2477 // classes are: the class itself; the class of which it is a
2478 // member, if any; and its direct and indirect base
2479 // classes. Its associated namespaces are the namespaces in
2480 // which its associated classes are defined.
2482 // Add the class of which it is a member, if any.
2483 DeclContext *Ctx = Class->getDeclContext();
2484 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2485 Result.Classes.insert(EnclosingClass);
2486 // Add the associated namespace for this class.
2487 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2489 // Add the class itself. If we've already seen this class, we don't
2490 // need to visit base classes.
2492 // FIXME: That's not correct, we may have added this class only because it
2493 // was the enclosing class of another class, and in that case we won't have
2494 // added its base classes yet.
2495 if (!Result.Classes.insert(Class))
2498 // -- If T is a template-id, its associated namespaces and classes are
2499 // the namespace in which the template is defined; for member
2500 // templates, the member template's class; the namespaces and classes
2501 // associated with the types of the template arguments provided for
2502 // template type parameters (excluding template template parameters); the
2503 // namespaces in which any template template arguments are defined; and
2504 // the classes in which any member templates used as template template
2505 // arguments are defined. [Note: non-type template arguments do not
2506 // contribute to the set of associated namespaces. ]
2507 if (ClassTemplateSpecializationDecl *Spec
2508 = dyn_cast<ClassTemplateSpecializationDecl>(Class)) {
2509 DeclContext *Ctx = Spec->getSpecializedTemplate()->getDeclContext();
2510 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2511 Result.Classes.insert(EnclosingClass);
2512 // Add the associated namespace for this class.
2513 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2515 const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
2516 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
2517 addAssociatedClassesAndNamespaces(Result, TemplateArgs[I]);
2520 // Only recurse into base classes for complete types.
2521 if (!Result.S.isCompleteType(Result.InstantiationLoc,
2522 Result.S.Context.getRecordType(Class)))
2525 // Add direct and indirect base classes along with their associated
2527 SmallVector<CXXRecordDecl *, 32> Bases;
2528 Bases.push_back(Class);
2529 while (!Bases.empty()) {
2530 // Pop this class off the stack.
2531 Class = Bases.pop_back_val();
2533 // Visit the base classes.
2534 for (const auto &Base : Class->bases()) {
2535 const RecordType *BaseType = Base.getType()->getAs<RecordType>();
2536 // In dependent contexts, we do ADL twice, and the first time around,
2537 // the base type might be a dependent TemplateSpecializationType, or a
2538 // TemplateTypeParmType. If that happens, simply ignore it.
2539 // FIXME: If we want to support export, we probably need to add the
2540 // namespace of the template in a TemplateSpecializationType, or even
2541 // the classes and namespaces of known non-dependent arguments.
2544 CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(BaseType->getDecl());
2545 if (Result.Classes.insert(BaseDecl)) {
2546 // Find the associated namespace for this base class.
2547 DeclContext *BaseCtx = BaseDecl->getDeclContext();
2548 CollectEnclosingNamespace(Result.Namespaces, BaseCtx);
2550 // Make sure we visit the bases of this base class.
2551 if (BaseDecl->bases_begin() != BaseDecl->bases_end())
2552 Bases.push_back(BaseDecl);
2558 // \brief Add the associated classes and namespaces for
2559 // argument-dependent lookup with an argument of type T
2560 // (C++ [basic.lookup.koenig]p2).
2562 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType Ty) {
2563 // C++ [basic.lookup.koenig]p2:
2565 // For each argument type T in the function call, there is a set
2566 // of zero or more associated namespaces and a set of zero or more
2567 // associated classes to be considered. The sets of namespaces and
2568 // classes is determined entirely by the types of the function
2569 // arguments (and the namespace of any template template
2570 // argument). Typedef names and using-declarations used to specify
2571 // the types do not contribute to this set. The sets of namespaces
2572 // and classes are determined in the following way:
2574 SmallVector<const Type *, 16> Queue;
2575 const Type *T = Ty->getCanonicalTypeInternal().getTypePtr();
2578 switch (T->getTypeClass()) {
2580 #define TYPE(Class, Base)
2581 #define DEPENDENT_TYPE(Class, Base) case Type::Class:
2582 #define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2583 #define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
2584 #define ABSTRACT_TYPE(Class, Base)
2585 #include "clang/AST/TypeNodes.def"
2586 // T is canonical. We can also ignore dependent types because
2587 // we don't need to do ADL at the definition point, but if we
2588 // wanted to implement template export (or if we find some other
2589 // use for associated classes and namespaces...) this would be
2593 // -- If T is a pointer to U or an array of U, its associated
2594 // namespaces and classes are those associated with U.
2596 T = cast<PointerType>(T)->getPointeeType().getTypePtr();
2598 case Type::ConstantArray:
2599 case Type::IncompleteArray:
2600 case Type::VariableArray:
2601 T = cast<ArrayType>(T)->getElementType().getTypePtr();
2604 // -- If T is a fundamental type, its associated sets of
2605 // namespaces and classes are both empty.
2609 // -- If T is a class type (including unions), its associated
2610 // classes are: the class itself; the class of which it is a
2611 // member, if any; and its direct and indirect base
2612 // classes. Its associated namespaces are the namespaces in
2613 // which its associated classes are defined.
2614 case Type::Record: {
2615 CXXRecordDecl *Class =
2616 cast<CXXRecordDecl>(cast<RecordType>(T)->getDecl());
2617 addAssociatedClassesAndNamespaces(Result, Class);
2621 // -- If T is an enumeration type, its associated namespace is
2622 // the namespace in which it is defined. If it is class
2623 // member, its associated class is the member's class; else
2624 // it has no associated class.
2626 EnumDecl *Enum = cast<EnumType>(T)->getDecl();
2628 DeclContext *Ctx = Enum->getDeclContext();
2629 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2630 Result.Classes.insert(EnclosingClass);
2632 // Add the associated namespace for this class.
2633 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2638 // -- If T is a function type, its associated namespaces and
2639 // classes are those associated with the function parameter
2640 // types and those associated with the return type.
2641 case Type::FunctionProto: {
2642 const FunctionProtoType *Proto = cast<FunctionProtoType>(T);
2643 for (const auto &Arg : Proto->param_types())
2644 Queue.push_back(Arg.getTypePtr());
2647 case Type::FunctionNoProto: {
2648 const FunctionType *FnType = cast<FunctionType>(T);
2649 T = FnType->getReturnType().getTypePtr();
2653 // -- If T is a pointer to a member function of a class X, its
2654 // associated namespaces and classes are those associated
2655 // with the function parameter types and return type,
2656 // together with those associated with X.
2658 // -- If T is a pointer to a data member of class X, its
2659 // associated namespaces and classes are those associated
2660 // with the member type together with those associated with
2662 case Type::MemberPointer: {
2663 const MemberPointerType *MemberPtr = cast<MemberPointerType>(T);
2665 // Queue up the class type into which this points.
2666 Queue.push_back(MemberPtr->getClass());
2668 // And directly continue with the pointee type.
2669 T = MemberPtr->getPointeeType().getTypePtr();
2673 // As an extension, treat this like a normal pointer.
2674 case Type::BlockPointer:
2675 T = cast<BlockPointerType>(T)->getPointeeType().getTypePtr();
2678 // References aren't covered by the standard, but that's such an
2679 // obvious defect that we cover them anyway.
2680 case Type::LValueReference:
2681 case Type::RValueReference:
2682 T = cast<ReferenceType>(T)->getPointeeType().getTypePtr();
2685 // These are fundamental types.
2687 case Type::ExtVector:
2691 // Non-deduced auto types only get here for error cases.
2695 // If T is an Objective-C object or interface type, or a pointer to an
2696 // object or interface type, the associated namespace is the global
2698 case Type::ObjCObject:
2699 case Type::ObjCInterface:
2700 case Type::ObjCObjectPointer:
2701 Result.Namespaces.insert(Result.S.Context.getTranslationUnitDecl());
2704 // Atomic types are just wrappers; use the associations of the
2707 T = cast<AtomicType>(T)->getValueType().getTypePtr();
2710 T = cast<PipeType>(T)->getElementType().getTypePtr();
2716 T = Queue.pop_back_val();
2720 /// \brief Find the associated classes and namespaces for
2721 /// argument-dependent lookup for a call with the given set of
2724 /// This routine computes the sets of associated classes and associated
2725 /// namespaces searched by argument-dependent lookup
2726 /// (C++ [basic.lookup.argdep]) for a given set of arguments.
2727 void Sema::FindAssociatedClassesAndNamespaces(
2728 SourceLocation InstantiationLoc, ArrayRef<Expr *> Args,
2729 AssociatedNamespaceSet &AssociatedNamespaces,
2730 AssociatedClassSet &AssociatedClasses) {
2731 AssociatedNamespaces.clear();
2732 AssociatedClasses.clear();
2734 AssociatedLookup Result(*this, InstantiationLoc,
2735 AssociatedNamespaces, AssociatedClasses);
2737 // C++ [basic.lookup.koenig]p2:
2738 // For each argument type T in the function call, there is a set
2739 // of zero or more associated namespaces and a set of zero or more
2740 // associated classes to be considered. The sets of namespaces and
2741 // classes is determined entirely by the types of the function
2742 // arguments (and the namespace of any template template
2744 for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) {
2745 Expr *Arg = Args[ArgIdx];
2747 if (Arg->getType() != Context.OverloadTy) {
2748 addAssociatedClassesAndNamespaces(Result, Arg->getType());
2752 // [...] In addition, if the argument is the name or address of a
2753 // set of overloaded functions and/or function templates, its
2754 // associated classes and namespaces are the union of those
2755 // associated with each of the members of the set: the namespace
2756 // in which the function or function template is defined and the
2757 // classes and namespaces associated with its (non-dependent)
2758 // parameter types and return type.
2759 Arg = Arg->IgnoreParens();
2760 if (UnaryOperator *unaryOp = dyn_cast<UnaryOperator>(Arg))
2761 if (unaryOp->getOpcode() == UO_AddrOf)
2762 Arg = unaryOp->getSubExpr();
2764 UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Arg);
2767 for (const auto *D : ULE->decls()) {
2768 // Look through any using declarations to find the underlying function.
2769 const FunctionDecl *FDecl = D->getUnderlyingDecl()->getAsFunction();
2771 // Add the classes and namespaces associated with the parameter
2772 // types and return type of this function.
2773 addAssociatedClassesAndNamespaces(Result, FDecl->getType());
2778 NamedDecl *Sema::LookupSingleName(Scope *S, DeclarationName Name,
2780 LookupNameKind NameKind,
2781 RedeclarationKind Redecl) {
2782 LookupResult R(*this, Name, Loc, NameKind, Redecl);
2784 return R.getAsSingle<NamedDecl>();
2787 /// \brief Find the protocol with the given name, if any.
2788 ObjCProtocolDecl *Sema::LookupProtocol(IdentifierInfo *II,
2789 SourceLocation IdLoc,
2790 RedeclarationKind Redecl) {
2791 Decl *D = LookupSingleName(TUScope, II, IdLoc,
2792 LookupObjCProtocolName, Redecl);
2793 return cast_or_null<ObjCProtocolDecl>(D);
2796 void Sema::LookupOverloadedOperatorName(OverloadedOperatorKind Op, Scope *S,
2797 QualType T1, QualType T2,
2798 UnresolvedSetImpl &Functions) {
2799 // C++ [over.match.oper]p3:
2800 // -- The set of non-member candidates is the result of the
2801 // unqualified lookup of operator@ in the context of the
2802 // expression according to the usual rules for name lookup in
2803 // unqualified function calls (3.4.2) except that all member
2804 // functions are ignored.
2805 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op);
2806 LookupResult Operators(*this, OpName, SourceLocation(), LookupOperatorName);
2807 LookupName(Operators, S);
2809 assert(!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous");
2810 Functions.append(Operators.begin(), Operators.end());
2813 Sema::SpecialMemberOverloadResult *Sema::LookupSpecialMember(CXXRecordDecl *RD,
2814 CXXSpecialMember SM,
2819 bool VolatileThis) {
2820 assert(CanDeclareSpecialMemberFunction(RD) &&
2821 "doing special member lookup into record that isn't fully complete");
2822 RD = RD->getDefinition();
2823 if (RValueThis || ConstThis || VolatileThis)
2824 assert((SM == CXXCopyAssignment || SM == CXXMoveAssignment) &&
2825 "constructors and destructors always have unqualified lvalue this");
2826 if (ConstArg || VolatileArg)
2827 assert((SM != CXXDefaultConstructor && SM != CXXDestructor) &&
2828 "parameter-less special members can't have qualified arguments");
2830 llvm::FoldingSetNodeID ID;
2833 ID.AddInteger(ConstArg);
2834 ID.AddInteger(VolatileArg);
2835 ID.AddInteger(RValueThis);
2836 ID.AddInteger(ConstThis);
2837 ID.AddInteger(VolatileThis);
2840 SpecialMemberOverloadResult *Result =
2841 SpecialMemberCache.FindNodeOrInsertPos(ID, InsertPoint);
2843 // This was already cached
2847 Result = BumpAlloc.Allocate<SpecialMemberOverloadResult>();
2848 Result = new (Result) SpecialMemberOverloadResult(ID);
2849 SpecialMemberCache.InsertNode(Result, InsertPoint);
2851 if (SM == CXXDestructor) {
2852 if (RD->needsImplicitDestructor())
2853 DeclareImplicitDestructor(RD);
2854 CXXDestructorDecl *DD = RD->getDestructor();
2855 assert(DD && "record without a destructor");
2856 Result->setMethod(DD);
2857 Result->setKind(DD->isDeleted() ?
2858 SpecialMemberOverloadResult::NoMemberOrDeleted :
2859 SpecialMemberOverloadResult::Success);
2863 // Prepare for overload resolution. Here we construct a synthetic argument
2864 // if necessary and make sure that implicit functions are declared.
2865 CanQualType CanTy = Context.getCanonicalType(Context.getTagDeclType(RD));
2866 DeclarationName Name;
2867 Expr *Arg = nullptr;
2870 QualType ArgType = CanTy;
2871 ExprValueKind VK = VK_LValue;
2873 if (SM == CXXDefaultConstructor) {
2874 Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
2876 if (RD->needsImplicitDefaultConstructor())
2877 DeclareImplicitDefaultConstructor(RD);
2879 if (SM == CXXCopyConstructor || SM == CXXMoveConstructor) {
2880 Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
2881 if (RD->needsImplicitCopyConstructor())
2882 DeclareImplicitCopyConstructor(RD);
2883 if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveConstructor())
2884 DeclareImplicitMoveConstructor(RD);
2886 Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
2887 if (RD->needsImplicitCopyAssignment())
2888 DeclareImplicitCopyAssignment(RD);
2889 if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveAssignment())
2890 DeclareImplicitMoveAssignment(RD);
2896 ArgType.addVolatile();
2898 // This isn't /really/ specified by the standard, but it's implied
2899 // we should be working from an RValue in the case of move to ensure
2900 // that we prefer to bind to rvalue references, and an LValue in the
2901 // case of copy to ensure we don't bind to rvalue references.
2902 // Possibly an XValue is actually correct in the case of move, but
2903 // there is no semantic difference for class types in this restricted
2905 if (SM == CXXCopyConstructor || SM == CXXCopyAssignment)
2911 OpaqueValueExpr FakeArg(SourceLocation(), ArgType, VK);
2913 if (SM != CXXDefaultConstructor) {
2918 // Create the object argument
2919 QualType ThisTy = CanTy;
2923 ThisTy.addVolatile();
2924 Expr::Classification Classification =
2925 OpaqueValueExpr(SourceLocation(), ThisTy,
2926 RValueThis ? VK_RValue : VK_LValue).Classify(Context);
2928 // Now we perform lookup on the name we computed earlier and do overload
2929 // resolution. Lookup is only performed directly into the class since there
2930 // will always be a (possibly implicit) declaration to shadow any others.
2931 OverloadCandidateSet OCS(RD->getLocation(), OverloadCandidateSet::CSK_Normal);
2932 DeclContext::lookup_result R = RD->lookup(Name);
2935 // We might have no default constructor because we have a lambda's closure
2936 // type, rather than because there's some other declared constructor.
2937 // Every class has a copy/move constructor, copy/move assignment, and
2939 assert(SM == CXXDefaultConstructor &&
2940 "lookup for a constructor or assignment operator was empty");
2941 Result->setMethod(nullptr);
2942 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
2946 // Copy the candidates as our processing of them may load new declarations
2947 // from an external source and invalidate lookup_result.
2948 SmallVector<NamedDecl *, 8> Candidates(R.begin(), R.end());
2950 for (NamedDecl *CandDecl : Candidates) {
2951 if (CandDecl->isInvalidDecl())
2954 DeclAccessPair Cand = DeclAccessPair::make(CandDecl, AS_public);
2955 auto CtorInfo = getConstructorInfo(Cand);
2956 if (CXXMethodDecl *M = dyn_cast<CXXMethodDecl>(Cand->getUnderlyingDecl())) {
2957 if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
2958 AddMethodCandidate(M, Cand, RD, ThisTy, Classification,
2959 llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
2961 AddOverloadCandidate(CtorInfo.Constructor, CtorInfo.FoundDecl,
2962 llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
2964 AddOverloadCandidate(M, Cand, llvm::makeArrayRef(&Arg, NumArgs), OCS,
2966 } else if (FunctionTemplateDecl *Tmpl =
2967 dyn_cast<FunctionTemplateDecl>(Cand->getUnderlyingDecl())) {
2968 if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
2969 AddMethodTemplateCandidate(
2970 Tmpl, Cand, RD, nullptr, ThisTy, Classification,
2971 llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
2973 AddTemplateOverloadCandidate(
2974 CtorInfo.ConstructorTmpl, CtorInfo.FoundDecl, nullptr,
2975 llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
2977 AddTemplateOverloadCandidate(
2978 Tmpl, Cand, nullptr, llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
2980 assert(isa<UsingDecl>(Cand.getDecl()) &&
2981 "illegal Kind of operator = Decl");
2985 OverloadCandidateSet::iterator Best;
2986 switch (OCS.BestViableFunction(*this, SourceLocation(), Best)) {
2988 Result->setMethod(cast<CXXMethodDecl>(Best->Function));
2989 Result->setKind(SpecialMemberOverloadResult::Success);
2993 Result->setMethod(cast<CXXMethodDecl>(Best->Function));
2994 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
2998 Result->setMethod(nullptr);
2999 Result->setKind(SpecialMemberOverloadResult::Ambiguous);
3002 case OR_No_Viable_Function:
3003 Result->setMethod(nullptr);
3004 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
3011 /// \brief Look up the default constructor for the given class.
3012 CXXConstructorDecl *Sema::LookupDefaultConstructor(CXXRecordDecl *Class) {
3013 SpecialMemberOverloadResult *Result =
3014 LookupSpecialMember(Class, CXXDefaultConstructor, false, false, false,
3017 return cast_or_null<CXXConstructorDecl>(Result->getMethod());
3020 /// \brief Look up the copying constructor for the given class.
3021 CXXConstructorDecl *Sema::LookupCopyingConstructor(CXXRecordDecl *Class,
3023 assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3024 "non-const, non-volatile qualifiers for copy ctor arg");
3025 SpecialMemberOverloadResult *Result =
3026 LookupSpecialMember(Class, CXXCopyConstructor, Quals & Qualifiers::Const,
3027 Quals & Qualifiers::Volatile, false, false, false);
3029 return cast_or_null<CXXConstructorDecl>(Result->getMethod());
3032 /// \brief Look up the moving constructor for the given class.
3033 CXXConstructorDecl *Sema::LookupMovingConstructor(CXXRecordDecl *Class,
3035 SpecialMemberOverloadResult *Result =
3036 LookupSpecialMember(Class, CXXMoveConstructor, Quals & Qualifiers::Const,
3037 Quals & Qualifiers::Volatile, false, false, false);
3039 return cast_or_null<CXXConstructorDecl>(Result->getMethod());
3042 /// \brief Look up the constructors for the given class.
3043 DeclContext::lookup_result Sema::LookupConstructors(CXXRecordDecl *Class) {
3044 // If the implicit constructors have not yet been declared, do so now.
3045 if (CanDeclareSpecialMemberFunction(Class)) {
3046 if (Class->needsImplicitDefaultConstructor())
3047 DeclareImplicitDefaultConstructor(Class);
3048 if (Class->needsImplicitCopyConstructor())
3049 DeclareImplicitCopyConstructor(Class);
3050 if (getLangOpts().CPlusPlus11 && Class->needsImplicitMoveConstructor())
3051 DeclareImplicitMoveConstructor(Class);
3054 CanQualType T = Context.getCanonicalType(Context.getTypeDeclType(Class));
3055 DeclarationName Name = Context.DeclarationNames.getCXXConstructorName(T);
3056 return Class->lookup(Name);
3059 /// \brief Look up the copying assignment operator for the given class.
3060 CXXMethodDecl *Sema::LookupCopyingAssignment(CXXRecordDecl *Class,
3061 unsigned Quals, bool RValueThis,
3062 unsigned ThisQuals) {
3063 assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3064 "non-const, non-volatile qualifiers for copy assignment arg");
3065 assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3066 "non-const, non-volatile qualifiers for copy assignment this");
3067 SpecialMemberOverloadResult *Result =
3068 LookupSpecialMember(Class, CXXCopyAssignment, Quals & Qualifiers::Const,
3069 Quals & Qualifiers::Volatile, RValueThis,
3070 ThisQuals & Qualifiers::Const,
3071 ThisQuals & Qualifiers::Volatile);
3073 return Result->getMethod();
3076 /// \brief Look up the moving assignment operator for the given class.
3077 CXXMethodDecl *Sema::LookupMovingAssignment(CXXRecordDecl *Class,
3080 unsigned ThisQuals) {
3081 assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3082 "non-const, non-volatile qualifiers for copy assignment this");
3083 SpecialMemberOverloadResult *Result =
3084 LookupSpecialMember(Class, CXXMoveAssignment, Quals & Qualifiers::Const,
3085 Quals & Qualifiers::Volatile, RValueThis,
3086 ThisQuals & Qualifiers::Const,
3087 ThisQuals & Qualifiers::Volatile);
3089 return Result->getMethod();
3092 /// \brief Look for the destructor of the given class.
3094 /// During semantic analysis, this routine should be used in lieu of
3095 /// CXXRecordDecl::getDestructor().
3097 /// \returns The destructor for this class.
3098 CXXDestructorDecl *Sema::LookupDestructor(CXXRecordDecl *Class) {
3099 return cast<CXXDestructorDecl>(LookupSpecialMember(Class, CXXDestructor,
3100 false, false, false,
3101 false, false)->getMethod());
3104 /// LookupLiteralOperator - Determine which literal operator should be used for
3105 /// a user-defined literal, per C++11 [lex.ext].
3107 /// Normal overload resolution is not used to select which literal operator to
3108 /// call for a user-defined literal. Look up the provided literal operator name,
3109 /// and filter the results to the appropriate set for the given argument types.
3110 Sema::LiteralOperatorLookupResult
3111 Sema::LookupLiteralOperator(Scope *S, LookupResult &R,
3112 ArrayRef<QualType> ArgTys,
3113 bool AllowRaw, bool AllowTemplate,
3114 bool AllowStringTemplate) {
3116 assert(R.getResultKind() != LookupResult::Ambiguous &&
3117 "literal operator lookup can't be ambiguous");
3119 // Filter the lookup results appropriately.
3120 LookupResult::Filter F = R.makeFilter();
3122 bool FoundRaw = false;
3123 bool FoundTemplate = false;
3124 bool FoundStringTemplate = false;
3125 bool FoundExactMatch = false;
3127 while (F.hasNext()) {
3129 if (UsingShadowDecl *USD = dyn_cast<UsingShadowDecl>(D))
3130 D = USD->getTargetDecl();
3132 // If the declaration we found is invalid, skip it.
3133 if (D->isInvalidDecl()) {
3139 bool IsTemplate = false;
3140 bool IsStringTemplate = false;
3141 bool IsExactMatch = false;
3143 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
3144 if (FD->getNumParams() == 1 &&
3145 FD->getParamDecl(0)->getType()->getAs<PointerType>())
3147 else if (FD->getNumParams() == ArgTys.size()) {
3148 IsExactMatch = true;
3149 for (unsigned ArgIdx = 0; ArgIdx != ArgTys.size(); ++ArgIdx) {
3150 QualType ParamTy = FD->getParamDecl(ArgIdx)->getType();
3151 if (!Context.hasSameUnqualifiedType(ArgTys[ArgIdx], ParamTy)) {
3152 IsExactMatch = false;
3158 if (FunctionTemplateDecl *FD = dyn_cast<FunctionTemplateDecl>(D)) {
3159 TemplateParameterList *Params = FD->getTemplateParameters();
3160 if (Params->size() == 1)
3163 IsStringTemplate = true;
3167 FoundExactMatch = true;
3169 AllowTemplate = false;
3170 AllowStringTemplate = false;
3171 if (FoundRaw || FoundTemplate || FoundStringTemplate) {
3172 // Go through again and remove the raw and template decls we've
3175 FoundRaw = FoundTemplate = FoundStringTemplate = false;
3177 } else if (AllowRaw && IsRaw) {
3179 } else if (AllowTemplate && IsTemplate) {
3180 FoundTemplate = true;
3181 } else if (AllowStringTemplate && IsStringTemplate) {
3182 FoundStringTemplate = true;
3190 // C++11 [lex.ext]p3, p4: If S contains a literal operator with a matching
3191 // parameter type, that is used in preference to a raw literal operator
3192 // or literal operator template.
3193 if (FoundExactMatch)
3196 // C++11 [lex.ext]p3, p4: S shall contain a raw literal operator or a literal
3197 // operator template, but not both.
3198 if (FoundRaw && FoundTemplate) {
3199 Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call) << R.getLookupName();
3200 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
3201 NoteOverloadCandidate(*I, (*I)->getUnderlyingDecl()->getAsFunction());
3209 return LOLR_Template;
3211 if (FoundStringTemplate)
3212 return LOLR_StringTemplate;
3214 // Didn't find anything we could use.
3215 Diag(R.getNameLoc(), diag::err_ovl_no_viable_literal_operator)
3216 << R.getLookupName() << (int)ArgTys.size() << ArgTys[0]
3217 << (ArgTys.size() == 2 ? ArgTys[1] : QualType()) << AllowRaw
3218 << (AllowTemplate || AllowStringTemplate);
3222 void ADLResult::insert(NamedDecl *New) {
3223 NamedDecl *&Old = Decls[cast<NamedDecl>(New->getCanonicalDecl())];
3225 // If we haven't yet seen a decl for this key, or the last decl
3226 // was exactly this one, we're done.
3227 if (Old == nullptr || Old == New) {
3232 // Otherwise, decide which is a more recent redeclaration.
3233 FunctionDecl *OldFD = Old->getAsFunction();
3234 FunctionDecl *NewFD = New->getAsFunction();
3236 FunctionDecl *Cursor = NewFD;
3238 Cursor = Cursor->getPreviousDecl();
3240 // If we got to the end without finding OldFD, OldFD is the newer
3241 // declaration; leave things as they are.
3242 if (!Cursor) return;
3244 // If we do find OldFD, then NewFD is newer.
3245 if (Cursor == OldFD) break;
3247 // Otherwise, keep looking.
3253 void Sema::ArgumentDependentLookup(DeclarationName Name, SourceLocation Loc,
3254 ArrayRef<Expr *> Args, ADLResult &Result) {
3255 // Find all of the associated namespaces and classes based on the
3256 // arguments we have.
3257 AssociatedNamespaceSet AssociatedNamespaces;
3258 AssociatedClassSet AssociatedClasses;
3259 FindAssociatedClassesAndNamespaces(Loc, Args,
3260 AssociatedNamespaces,
3263 // C++ [basic.lookup.argdep]p3:
3264 // Let X be the lookup set produced by unqualified lookup (3.4.1)
3265 // and let Y be the lookup set produced by argument dependent
3266 // lookup (defined as follows). If X contains [...] then Y is
3267 // empty. Otherwise Y is the set of declarations found in the
3268 // namespaces associated with the argument types as described
3269 // below. The set of declarations found by the lookup of the name
3270 // is the union of X and Y.
3272 // Here, we compute Y and add its members to the overloaded
3274 for (auto *NS : AssociatedNamespaces) {
3275 // When considering an associated namespace, the lookup is the
3276 // same as the lookup performed when the associated namespace is
3277 // used as a qualifier (3.4.3.2) except that:
3279 // -- Any using-directives in the associated namespace are
3282 // -- Any namespace-scope friend functions declared in
3283 // associated classes are visible within their respective
3284 // namespaces even if they are not visible during an ordinary
3286 DeclContext::lookup_result R = NS->lookup(Name);
3288 // If the only declaration here is an ordinary friend, consider
3289 // it only if it was declared in an associated classes.
3290 if ((D->getIdentifierNamespace() & Decl::IDNS_Ordinary) == 0) {
3291 // If it's neither ordinarily visible nor a friend, we can't find it.
3292 if ((D->getIdentifierNamespace() & Decl::IDNS_OrdinaryFriend) == 0)
3295 bool DeclaredInAssociatedClass = false;
3296 for (Decl *DI = D; DI; DI = DI->getPreviousDecl()) {
3297 DeclContext *LexDC = DI->getLexicalDeclContext();
3298 if (isa<CXXRecordDecl>(LexDC) &&
3299 AssociatedClasses.count(cast<CXXRecordDecl>(LexDC)) &&
3300 isVisible(cast<NamedDecl>(DI))) {
3301 DeclaredInAssociatedClass = true;
3305 if (!DeclaredInAssociatedClass)
3309 if (isa<UsingShadowDecl>(D))
3310 D = cast<UsingShadowDecl>(D)->getTargetDecl();
3312 if (!isa<FunctionDecl>(D) && !isa<FunctionTemplateDecl>(D))
3315 if (!isVisible(D) && !(D = findAcceptableDecl(*this, D)))
3323 //----------------------------------------------------------------------------
3324 // Search for all visible declarations.
3325 //----------------------------------------------------------------------------
3326 VisibleDeclConsumer::~VisibleDeclConsumer() { }
3328 bool VisibleDeclConsumer::includeHiddenDecls() const { return false; }
3332 class ShadowContextRAII;
3334 class VisibleDeclsRecord {
3336 /// \brief An entry in the shadow map, which is optimized to store a
3337 /// single declaration (the common case) but can also store a list
3338 /// of declarations.
3339 typedef llvm::TinyPtrVector<NamedDecl*> ShadowMapEntry;
3342 /// \brief A mapping from declaration names to the declarations that have
3343 /// this name within a particular scope.
3344 typedef llvm::DenseMap<DeclarationName, ShadowMapEntry> ShadowMap;
3346 /// \brief A list of shadow maps, which is used to model name hiding.
3347 std::list<ShadowMap> ShadowMaps;
3349 /// \brief The declaration contexts we have already visited.
3350 llvm::SmallPtrSet<DeclContext *, 8> VisitedContexts;
3352 friend class ShadowContextRAII;
3355 /// \brief Determine whether we have already visited this context
3356 /// (and, if not, note that we are going to visit that context now).
3357 bool visitedContext(DeclContext *Ctx) {
3358 return !VisitedContexts.insert(Ctx).second;
3361 bool alreadyVisitedContext(DeclContext *Ctx) {
3362 return VisitedContexts.count(Ctx);
3365 /// \brief Determine whether the given declaration is hidden in the
3368 /// \returns the declaration that hides the given declaration, or
3369 /// NULL if no such declaration exists.
3370 NamedDecl *checkHidden(NamedDecl *ND);
3372 /// \brief Add a declaration to the current shadow map.
3373 void add(NamedDecl *ND) {
3374 ShadowMaps.back()[ND->getDeclName()].push_back(ND);
3378 /// \brief RAII object that records when we've entered a shadow context.
3379 class ShadowContextRAII {
3380 VisibleDeclsRecord &Visible;
3382 typedef VisibleDeclsRecord::ShadowMap ShadowMap;
3385 ShadowContextRAII(VisibleDeclsRecord &Visible) : Visible(Visible) {
3386 Visible.ShadowMaps.emplace_back();
3389 ~ShadowContextRAII() {
3390 Visible.ShadowMaps.pop_back();
3394 } // end anonymous namespace
3396 NamedDecl *VisibleDeclsRecord::checkHidden(NamedDecl *ND) {
3397 unsigned IDNS = ND->getIdentifierNamespace();
3398 std::list<ShadowMap>::reverse_iterator SM = ShadowMaps.rbegin();
3399 for (std::list<ShadowMap>::reverse_iterator SMEnd = ShadowMaps.rend();
3400 SM != SMEnd; ++SM) {
3401 ShadowMap::iterator Pos = SM->find(ND->getDeclName());
3402 if (Pos == SM->end())
3405 for (auto *D : Pos->second) {
3406 // A tag declaration does not hide a non-tag declaration.
3407 if (D->hasTagIdentifierNamespace() &&
3408 (IDNS & (Decl::IDNS_Member | Decl::IDNS_Ordinary |
3409 Decl::IDNS_ObjCProtocol)))
3412 // Protocols are in distinct namespaces from everything else.
3413 if (((D->getIdentifierNamespace() & Decl::IDNS_ObjCProtocol)
3414 || (IDNS & Decl::IDNS_ObjCProtocol)) &&
3415 D->getIdentifierNamespace() != IDNS)
3418 // Functions and function templates in the same scope overload
3419 // rather than hide. FIXME: Look for hiding based on function
3421 if (D->getUnderlyingDecl()->isFunctionOrFunctionTemplate() &&
3422 ND->getUnderlyingDecl()->isFunctionOrFunctionTemplate() &&
3423 SM == ShadowMaps.rbegin())
3426 // We've found a declaration that hides this one.
3434 static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
3435 bool QualifiedNameLookup,
3437 VisibleDeclConsumer &Consumer,
3438 VisibleDeclsRecord &Visited) {
3442 // Make sure we don't visit the same context twice.
3443 if (Visited.visitedContext(Ctx->getPrimaryContext()))
3446 // Outside C++, lookup results for the TU live on identifiers.
3447 if (isa<TranslationUnitDecl>(Ctx) &&
3448 !Result.getSema().getLangOpts().CPlusPlus) {
3449 auto &S = Result.getSema();
3450 auto &Idents = S.Context.Idents;
3452 // Ensure all external identifiers are in the identifier table.
3453 if (IdentifierInfoLookup *External = Idents.getExternalIdentifierLookup()) {
3454 std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
3455 for (StringRef Name = Iter->Next(); !Name.empty(); Name = Iter->Next())
3459 // Walk all lookup results in the TU for each identifier.
3460 for (const auto &Ident : Idents) {
3461 for (auto I = S.IdResolver.begin(Ident.getValue()),
3462 E = S.IdResolver.end();
3464 if (S.IdResolver.isDeclInScope(*I, Ctx)) {
3465 if (NamedDecl *ND = Result.getAcceptableDecl(*I)) {
3466 Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
3476 if (CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(Ctx))
3477 Result.getSema().ForceDeclarationOfImplicitMembers(Class);
3479 // Enumerate all of the results in this context.
3480 for (DeclContextLookupResult R : Ctx->lookups()) {
3482 if (auto *ND = Result.getAcceptableDecl(D)) {
3483 Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
3489 // Traverse using directives for qualified name lookup.
3490 if (QualifiedNameLookup) {
3491 ShadowContextRAII Shadow(Visited);
3492 for (auto I : Ctx->using_directives()) {
3493 LookupVisibleDecls(I->getNominatedNamespace(), Result,
3494 QualifiedNameLookup, InBaseClass, Consumer, Visited);
3498 // Traverse the contexts of inherited C++ classes.
3499 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) {
3500 if (!Record->hasDefinition())
3503 for (const auto &B : Record->bases()) {
3504 QualType BaseType = B.getType();
3506 // Don't look into dependent bases, because name lookup can't look
3508 if (BaseType->isDependentType())
3511 const RecordType *Record = BaseType->getAs<RecordType>();
3515 // FIXME: It would be nice to be able to determine whether referencing
3516 // a particular member would be ambiguous. For example, given
3518 // struct A { int member; };
3519 // struct B { int member; };
3520 // struct C : A, B { };
3522 // void f(C *c) { c->### }
3524 // accessing 'member' would result in an ambiguity. However, we
3525 // could be smart enough to qualify the member with the base
3534 // Find results in this base class (and its bases).
3535 ShadowContextRAII Shadow(Visited);
3536 LookupVisibleDecls(Record->getDecl(), Result, QualifiedNameLookup,
3537 true, Consumer, Visited);
3541 // Traverse the contexts of Objective-C classes.
3542 if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>(Ctx)) {
3543 // Traverse categories.
3544 for (auto *Cat : IFace->visible_categories()) {
3545 ShadowContextRAII Shadow(Visited);
3546 LookupVisibleDecls(Cat, Result, QualifiedNameLookup, false,
3550 // Traverse protocols.
3551 for (auto *I : IFace->all_referenced_protocols()) {
3552 ShadowContextRAII Shadow(Visited);
3553 LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3557 // Traverse the superclass.
3558 if (IFace->getSuperClass()) {
3559 ShadowContextRAII Shadow(Visited);
3560 LookupVisibleDecls(IFace->getSuperClass(), Result, QualifiedNameLookup,
3561 true, Consumer, Visited);
3564 // If there is an implementation, traverse it. We do this to find
3565 // synthesized ivars.
3566 if (IFace->getImplementation()) {
3567 ShadowContextRAII Shadow(Visited);
3568 LookupVisibleDecls(IFace->getImplementation(), Result,
3569 QualifiedNameLookup, InBaseClass, Consumer, Visited);
3571 } else if (ObjCProtocolDecl *Protocol = dyn_cast<ObjCProtocolDecl>(Ctx)) {
3572 for (auto *I : Protocol->protocols()) {
3573 ShadowContextRAII Shadow(Visited);
3574 LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3577 } else if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(Ctx)) {
3578 for (auto *I : Category->protocols()) {
3579 ShadowContextRAII Shadow(Visited);
3580 LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3584 // If there is an implementation, traverse it.
3585 if (Category->getImplementation()) {
3586 ShadowContextRAII Shadow(Visited);
3587 LookupVisibleDecls(Category->getImplementation(), Result,
3588 QualifiedNameLookup, true, Consumer, Visited);
3593 static void LookupVisibleDecls(Scope *S, LookupResult &Result,
3594 UnqualUsingDirectiveSet &UDirs,
3595 VisibleDeclConsumer &Consumer,
3596 VisibleDeclsRecord &Visited) {
3600 if (!S->getEntity() ||
3602 !Visited.alreadyVisitedContext(S->getEntity())) ||
3603 (S->getEntity())->isFunctionOrMethod()) {
3604 FindLocalExternScope FindLocals(Result);
3605 // Walk through the declarations in this Scope.
3606 for (auto *D : S->decls()) {
3607 if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
3608 if ((ND = Result.getAcceptableDecl(ND))) {
3609 Consumer.FoundDecl(ND, Visited.checkHidden(ND), nullptr, false);
3615 // FIXME: C++ [temp.local]p8
3616 DeclContext *Entity = nullptr;
3617 if (S->getEntity()) {
3618 // Look into this scope's declaration context, along with any of its
3619 // parent lookup contexts (e.g., enclosing classes), up to the point
3620 // where we hit the context stored in the next outer scope.
3621 Entity = S->getEntity();
3622 DeclContext *OuterCtx = findOuterContext(S).first; // FIXME
3624 for (DeclContext *Ctx = Entity; Ctx && !Ctx->Equals(OuterCtx);
3625 Ctx = Ctx->getLookupParent()) {
3626 if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
3627 if (Method->isInstanceMethod()) {
3628 // For instance methods, look for ivars in the method's interface.
3629 LookupResult IvarResult(Result.getSema(), Result.getLookupName(),
3630 Result.getNameLoc(), Sema::LookupMemberName);
3631 if (ObjCInterfaceDecl *IFace = Method->getClassInterface()) {
3632 LookupVisibleDecls(IFace, IvarResult, /*QualifiedNameLookup=*/false,
3633 /*InBaseClass=*/false, Consumer, Visited);
3637 // We've already performed all of the name lookup that we need
3638 // to for Objective-C methods; the next context will be the
3643 if (Ctx->isFunctionOrMethod())
3646 LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/false,
3647 /*InBaseClass=*/false, Consumer, Visited);
3649 } else if (!S->getParent()) {
3650 // Look into the translation unit scope. We walk through the translation
3651 // unit's declaration context, because the Scope itself won't have all of
3652 // the declarations if we loaded a precompiled header.
3653 // FIXME: We would like the translation unit's Scope object to point to the
3654 // translation unit, so we don't need this special "if" branch. However,
3655 // doing so would force the normal C++ name-lookup code to look into the
3656 // translation unit decl when the IdentifierInfo chains would suffice.
3657 // Once we fix that problem (which is part of a more general "don't look
3658 // in DeclContexts unless we have to" optimization), we can eliminate this.
3659 Entity = Result.getSema().Context.getTranslationUnitDecl();
3660 LookupVisibleDecls(Entity, Result, /*QualifiedNameLookup=*/false,
3661 /*InBaseClass=*/false, Consumer, Visited);
3665 // Lookup visible declarations in any namespaces found by using
3667 for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(Entity))
3668 LookupVisibleDecls(const_cast<DeclContext *>(UUE.getNominatedNamespace()),
3669 Result, /*QualifiedNameLookup=*/false,
3670 /*InBaseClass=*/false, Consumer, Visited);
3673 // Lookup names in the parent scope.
3674 ShadowContextRAII Shadow(Visited);
3675 LookupVisibleDecls(S->getParent(), Result, UDirs, Consumer, Visited);
3678 void Sema::LookupVisibleDecls(Scope *S, LookupNameKind Kind,
3679 VisibleDeclConsumer &Consumer,
3680 bool IncludeGlobalScope) {
3681 // Determine the set of using directives available during
3682 // unqualified name lookup.
3684 UnqualUsingDirectiveSet UDirs;
3685 if (getLangOpts().CPlusPlus) {
3686 // Find the first namespace or translation-unit scope.
3687 while (S && !isNamespaceOrTranslationUnitScope(S))
3690 UDirs.visitScopeChain(Initial, S);
3694 // Look for visible declarations.
3695 LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
3696 Result.setAllowHidden(Consumer.includeHiddenDecls());
3697 VisibleDeclsRecord Visited;
3698 if (!IncludeGlobalScope)
3699 Visited.visitedContext(Context.getTranslationUnitDecl());
3700 ShadowContextRAII Shadow(Visited);
3701 ::LookupVisibleDecls(Initial, Result, UDirs, Consumer, Visited);
3704 void Sema::LookupVisibleDecls(DeclContext *Ctx, LookupNameKind Kind,
3705 VisibleDeclConsumer &Consumer,
3706 bool IncludeGlobalScope) {
3707 LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
3708 Result.setAllowHidden(Consumer.includeHiddenDecls());
3709 VisibleDeclsRecord Visited;
3710 if (!IncludeGlobalScope)
3711 Visited.visitedContext(Context.getTranslationUnitDecl());
3712 ShadowContextRAII Shadow(Visited);
3713 ::LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/true,
3714 /*InBaseClass=*/false, Consumer, Visited);
3717 /// LookupOrCreateLabel - Do a name lookup of a label with the specified name.
3718 /// If GnuLabelLoc is a valid source location, then this is a definition
3719 /// of an __label__ label name, otherwise it is a normal label definition
3721 LabelDecl *Sema::LookupOrCreateLabel(IdentifierInfo *II, SourceLocation Loc,
3722 SourceLocation GnuLabelLoc) {
3723 // Do a lookup to see if we have a label with this name already.
3724 NamedDecl *Res = nullptr;
3726 if (GnuLabelLoc.isValid()) {
3727 // Local label definitions always shadow existing labels.
3728 Res = LabelDecl::Create(Context, CurContext, Loc, II, GnuLabelLoc);
3729 Scope *S = CurScope;
3730 PushOnScopeChains(Res, S, true);
3731 return cast<LabelDecl>(Res);
3734 // Not a GNU local label.
3735 Res = LookupSingleName(CurScope, II, Loc, LookupLabel, NotForRedeclaration);
3736 // If we found a label, check to see if it is in the same context as us.
3737 // When in a Block, we don't want to reuse a label in an enclosing function.
3738 if (Res && Res->getDeclContext() != CurContext)
3741 // If not forward referenced or defined already, create the backing decl.
3742 Res = LabelDecl::Create(Context, CurContext, Loc, II);
3743 Scope *S = CurScope->getFnParent();
3744 assert(S && "Not in a function?");
3745 PushOnScopeChains(Res, S, true);
3747 return cast<LabelDecl>(Res);
3750 //===----------------------------------------------------------------------===//
3752 //===----------------------------------------------------------------------===//
3754 static bool isCandidateViable(CorrectionCandidateCallback &CCC,
3755 TypoCorrection &Candidate) {
3756 Candidate.setCallbackDistance(CCC.RankCandidate(Candidate));
3757 return Candidate.getEditDistance(false) != TypoCorrection::InvalidDistance;
3760 static void LookupPotentialTypoResult(Sema &SemaRef,
3762 IdentifierInfo *Name,
3763 Scope *S, CXXScopeSpec *SS,
3764 DeclContext *MemberContext,
3765 bool EnteringContext,
3766 bool isObjCIvarLookup,
3769 /// \brief Check whether the declarations found for a typo correction are
3770 /// visible, and if none of them are, convert the correction to an 'import
3771 /// a module' correction.
3772 static void checkCorrectionVisibility(Sema &SemaRef, TypoCorrection &TC) {
3773 if (TC.begin() == TC.end())
3776 TypoCorrection::decl_iterator DI = TC.begin(), DE = TC.end();
3778 for (/**/; DI != DE; ++DI)
3779 if (!LookupResult::isVisible(SemaRef, *DI))
3781 // Nothing to do if all decls are visible.
3785 llvm::SmallVector<NamedDecl*, 4> NewDecls(TC.begin(), DI);
3786 bool AnyVisibleDecls = !NewDecls.empty();
3788 for (/**/; DI != DE; ++DI) {
3789 NamedDecl *VisibleDecl = *DI;
3790 if (!LookupResult::isVisible(SemaRef, *DI))
3791 VisibleDecl = findAcceptableDecl(SemaRef, *DI);
3794 if (!AnyVisibleDecls) {
3795 // Found a visible decl, discard all hidden ones.
3796 AnyVisibleDecls = true;
3799 NewDecls.push_back(VisibleDecl);
3800 } else if (!AnyVisibleDecls && !(*DI)->isModulePrivate())
3801 NewDecls.push_back(*DI);
3804 if (NewDecls.empty())
3805 TC = TypoCorrection();
3807 TC.setCorrectionDecls(NewDecls);
3808 TC.setRequiresImport(!AnyVisibleDecls);
3812 // Fill the supplied vector with the IdentifierInfo pointers for each piece of
3813 // the given NestedNameSpecifier (i.e. given a NestedNameSpecifier "foo::bar::",
3814 // fill the vector with the IdentifierInfo pointers for "foo" and "bar").
3815 static void getNestedNameSpecifierIdentifiers(
3816 NestedNameSpecifier *NNS,
3817 SmallVectorImpl<const IdentifierInfo*> &Identifiers) {
3818 if (NestedNameSpecifier *Prefix = NNS->getPrefix())
3819 getNestedNameSpecifierIdentifiers(Prefix, Identifiers);
3821 Identifiers.clear();
3823 const IdentifierInfo *II = nullptr;
3825 switch (NNS->getKind()) {
3826 case NestedNameSpecifier::Identifier:
3827 II = NNS->getAsIdentifier();
3830 case NestedNameSpecifier::Namespace:
3831 if (NNS->getAsNamespace()->isAnonymousNamespace())
3833 II = NNS->getAsNamespace()->getIdentifier();
3836 case NestedNameSpecifier::NamespaceAlias:
3837 II = NNS->getAsNamespaceAlias()->getIdentifier();
3840 case NestedNameSpecifier::TypeSpecWithTemplate:
3841 case NestedNameSpecifier::TypeSpec:
3842 II = QualType(NNS->getAsType(), 0).getBaseTypeIdentifier();
3845 case NestedNameSpecifier::Global:
3846 case NestedNameSpecifier::Super:
3851 Identifiers.push_back(II);
3854 void TypoCorrectionConsumer::FoundDecl(NamedDecl *ND, NamedDecl *Hiding,
3855 DeclContext *Ctx, bool InBaseClass) {
3856 // Don't consider hidden names for typo correction.
3860 // Only consider entities with identifiers for names, ignoring
3861 // special names (constructors, overloaded operators, selectors,
3863 IdentifierInfo *Name = ND->getIdentifier();
3867 // Only consider visible declarations and declarations from modules with
3868 // names that exactly match.
3869 if (!LookupResult::isVisible(SemaRef, ND) && Name != Typo &&
3870 !findAcceptableDecl(SemaRef, ND))
3873 FoundName(Name->getName());
3876 void TypoCorrectionConsumer::FoundName(StringRef Name) {
3877 // Compute the edit distance between the typo and the name of this
3878 // entity, and add the identifier to the list of results.
3879 addName(Name, nullptr);
3882 void TypoCorrectionConsumer::addKeywordResult(StringRef Keyword) {
3883 // Compute the edit distance between the typo and this keyword,
3884 // and add the keyword to the list of results.
3885 addName(Keyword, nullptr, nullptr, true);
3888 void TypoCorrectionConsumer::addName(StringRef Name, NamedDecl *ND,
3889 NestedNameSpecifier *NNS, bool isKeyword) {
3890 // Use a simple length-based heuristic to determine the minimum possible
3891 // edit distance. If the minimum isn't good enough, bail out early.
3892 StringRef TypoStr = Typo->getName();
3893 unsigned MinED = abs((int)Name.size() - (int)TypoStr.size());
3894 if (MinED && TypoStr.size() / MinED < 3)
3897 // Compute an upper bound on the allowable edit distance, so that the
3898 // edit-distance algorithm can short-circuit.
3899 unsigned UpperBound = (TypoStr.size() + 2) / 3 + 1;
3900 unsigned ED = TypoStr.edit_distance(Name, true, UpperBound);
3901 if (ED >= UpperBound) return;
3903 TypoCorrection TC(&SemaRef.Context.Idents.get(Name), ND, NNS, ED);
3904 if (isKeyword) TC.makeKeyword();
3905 TC.setCorrectionRange(nullptr, Result.getLookupNameInfo());
3909 static const unsigned MaxTypoDistanceResultSets = 5;
3911 void TypoCorrectionConsumer::addCorrection(TypoCorrection Correction) {
3912 StringRef TypoStr = Typo->getName();
3913 StringRef Name = Correction.getCorrectionAsIdentifierInfo()->getName();
3915 // For very short typos, ignore potential corrections that have a different
3916 // base identifier from the typo or which have a normalized edit distance
3917 // longer than the typo itself.
3918 if (TypoStr.size() < 3 &&
3919 (Name != TypoStr || Correction.getEditDistance(true) > TypoStr.size()))
3922 // If the correction is resolved but is not viable, ignore it.
3923 if (Correction.isResolved()) {
3924 checkCorrectionVisibility(SemaRef, Correction);
3925 if (!Correction || !isCandidateViable(*CorrectionValidator, Correction))
3929 TypoResultList &CList =
3930 CorrectionResults[Correction.getEditDistance(false)][Name];
3932 if (!CList.empty() && !CList.back().isResolved())
3934 if (NamedDecl *NewND = Correction.getCorrectionDecl()) {
3935 std::string CorrectionStr = Correction.getAsString(SemaRef.getLangOpts());
3936 for (TypoResultList::iterator RI = CList.begin(), RIEnd = CList.end();
3937 RI != RIEnd; ++RI) {
3938 // If the Correction refers to a decl already in the result list,
3939 // replace the existing result if the string representation of Correction
3940 // comes before the current result alphabetically, then stop as there is
3941 // nothing more to be done to add Correction to the candidate set.
3942 if (RI->getCorrectionDecl() == NewND) {
3943 if (CorrectionStr < RI->getAsString(SemaRef.getLangOpts()))
3949 if (CList.empty() || Correction.isResolved())
3950 CList.push_back(Correction);
3952 while (CorrectionResults.size() > MaxTypoDistanceResultSets)
3953 CorrectionResults.erase(std::prev(CorrectionResults.end()));
3956 void TypoCorrectionConsumer::addNamespaces(
3957 const llvm::MapVector<NamespaceDecl *, bool> &KnownNamespaces) {
3958 SearchNamespaces = true;
3960 for (auto KNPair : KnownNamespaces)
3961 Namespaces.addNameSpecifier(KNPair.first);
3963 bool SSIsTemplate = false;
3964 if (NestedNameSpecifier *NNS =
3965 (SS && SS->isValid()) ? SS->getScopeRep() : nullptr) {
3966 if (const Type *T = NNS->getAsType())
3967 SSIsTemplate = T->getTypeClass() == Type::TemplateSpecialization;
3969 // Do not transform this into an iterator-based loop. The loop body can
3970 // trigger the creation of further types (through lazy deserialization) and
3971 // invalide iterators into this list.
3972 auto &Types = SemaRef.getASTContext().getTypes();
3973 for (unsigned I = 0; I != Types.size(); ++I) {
3974 const auto *TI = Types[I];
3975 if (CXXRecordDecl *CD = TI->getAsCXXRecordDecl()) {
3976 CD = CD->getCanonicalDecl();
3977 if (!CD->isDependentType() && !CD->isAnonymousStructOrUnion() &&
3978 !CD->isUnion() && CD->getIdentifier() &&
3979 (SSIsTemplate || !isa<ClassTemplateSpecializationDecl>(CD)) &&
3980 (CD->isBeingDefined() || CD->isCompleteDefinition()))
3981 Namespaces.addNameSpecifier(CD);
3986 const TypoCorrection &TypoCorrectionConsumer::getNextCorrection() {
3987 if (++CurrentTCIndex < ValidatedCorrections.size())
3988 return ValidatedCorrections[CurrentTCIndex];
3990 CurrentTCIndex = ValidatedCorrections.size();
3991 while (!CorrectionResults.empty()) {
3992 auto DI = CorrectionResults.begin();
3993 if (DI->second.empty()) {
3994 CorrectionResults.erase(DI);
3998 auto RI = DI->second.begin();
3999 if (RI->second.empty()) {
4000 DI->second.erase(RI);
4001 performQualifiedLookups();
4005 TypoCorrection TC = RI->second.pop_back_val();
4006 if (TC.isResolved() || TC.requiresImport() || resolveCorrection(TC)) {
4007 ValidatedCorrections.push_back(TC);
4008 return ValidatedCorrections[CurrentTCIndex];
4011 return ValidatedCorrections[0]; // The empty correction.
4014 bool TypoCorrectionConsumer::resolveCorrection(TypoCorrection &Candidate) {
4015 IdentifierInfo *Name = Candidate.getCorrectionAsIdentifierInfo();
4016 DeclContext *TempMemberContext = MemberContext;
4017 CXXScopeSpec *TempSS = SS.get();
4019 LookupPotentialTypoResult(SemaRef, Result, Name, S, TempSS, TempMemberContext,
4021 CorrectionValidator->IsObjCIvarLookup,
4022 Name == Typo && !Candidate.WillReplaceSpecifier());
4023 switch (Result.getResultKind()) {
4024 case LookupResult::NotFound:
4025 case LookupResult::NotFoundInCurrentInstantiation:
4026 case LookupResult::FoundUnresolvedValue:
4028 // Immediately retry the lookup without the given CXXScopeSpec
4030 Candidate.WillReplaceSpecifier(true);
4033 if (TempMemberContext) {
4036 TempMemberContext = nullptr;
4039 if (SearchNamespaces)
4040 QualifiedResults.push_back(Candidate);
4043 case LookupResult::Ambiguous:
4044 // We don't deal with ambiguities.
4047 case LookupResult::Found:
4048 case LookupResult::FoundOverloaded:
4049 // Store all of the Decls for overloaded symbols
4050 for (auto *TRD : Result)
4051 Candidate.addCorrectionDecl(TRD);
4052 checkCorrectionVisibility(SemaRef, Candidate);
4053 if (!isCandidateViable(*CorrectionValidator, Candidate)) {
4054 if (SearchNamespaces)
4055 QualifiedResults.push_back(Candidate);
4058 Candidate.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
4064 void TypoCorrectionConsumer::performQualifiedLookups() {
4065 unsigned TypoLen = Typo->getName().size();
4066 for (const TypoCorrection &QR : QualifiedResults) {
4067 for (const auto &NSI : Namespaces) {
4068 DeclContext *Ctx = NSI.DeclCtx;
4069 const Type *NSType = NSI.NameSpecifier->getAsType();
4071 // If the current NestedNameSpecifier refers to a class and the
4072 // current correction candidate is the name of that class, then skip
4073 // it as it is unlikely a qualified version of the class' constructor
4074 // is an appropriate correction.
4075 if (CXXRecordDecl *NSDecl = NSType ? NSType->getAsCXXRecordDecl() :
4077 if (NSDecl->getIdentifier() == QR.getCorrectionAsIdentifierInfo())
4081 TypoCorrection TC(QR);
4082 TC.ClearCorrectionDecls();
4083 TC.setCorrectionSpecifier(NSI.NameSpecifier);
4084 TC.setQualifierDistance(NSI.EditDistance);
4085 TC.setCallbackDistance(0); // Reset the callback distance
4087 // If the current correction candidate and namespace combination are
4088 // too far away from the original typo based on the normalized edit
4089 // distance, then skip performing a qualified name lookup.
4090 unsigned TmpED = TC.getEditDistance(true);
4091 if (QR.getCorrectionAsIdentifierInfo() != Typo && TmpED &&
4092 TypoLen / TmpED < 3)
4096 Result.setLookupName(QR.getCorrectionAsIdentifierInfo());
4097 if (!SemaRef.LookupQualifiedName(Result, Ctx))
4100 // Any corrections added below will be validated in subsequent
4101 // iterations of the main while() loop over the Consumer's contents.
4102 switch (Result.getResultKind()) {
4103 case LookupResult::Found:
4104 case LookupResult::FoundOverloaded: {
4105 if (SS && SS->isValid()) {
4106 std::string NewQualified = TC.getAsString(SemaRef.getLangOpts());
4107 std::string OldQualified;
4108 llvm::raw_string_ostream OldOStream(OldQualified);
4109 SS->getScopeRep()->print(OldOStream, SemaRef.getPrintingPolicy());
4110 OldOStream << Typo->getName();
4111 // If correction candidate would be an identical written qualified
4112 // identifer, then the existing CXXScopeSpec probably included a
4113 // typedef that didn't get accounted for properly.
4114 if (OldOStream.str() == NewQualified)
4117 for (LookupResult::iterator TRD = Result.begin(), TRDEnd = Result.end();
4118 TRD != TRDEnd; ++TRD) {
4119 if (SemaRef.CheckMemberAccess(TC.getCorrectionRange().getBegin(),
4120 NSType ? NSType->getAsCXXRecordDecl()
4122 TRD.getPair()) == Sema::AR_accessible)
4123 TC.addCorrectionDecl(*TRD);
4125 if (TC.isResolved()) {
4126 TC.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
4131 case LookupResult::NotFound:
4132 case LookupResult::NotFoundInCurrentInstantiation:
4133 case LookupResult::Ambiguous:
4134 case LookupResult::FoundUnresolvedValue:
4139 QualifiedResults.clear();
4142 TypoCorrectionConsumer::NamespaceSpecifierSet::NamespaceSpecifierSet(
4143 ASTContext &Context, DeclContext *CurContext, CXXScopeSpec *CurScopeSpec)
4144 : Context(Context), CurContextChain(buildContextChain(CurContext)) {
4145 if (NestedNameSpecifier *NNS =
4146 CurScopeSpec ? CurScopeSpec->getScopeRep() : nullptr) {
4147 llvm::raw_string_ostream SpecifierOStream(CurNameSpecifier);
4148 NNS->print(SpecifierOStream, Context.getPrintingPolicy());
4150 getNestedNameSpecifierIdentifiers(NNS, CurNameSpecifierIdentifiers);
4152 // Build the list of identifiers that would be used for an absolute
4153 // (from the global context) NestedNameSpecifier referring to the current
4155 for (DeclContext *C : llvm::reverse(CurContextChain)) {
4156 if (auto *ND = dyn_cast_or_null<NamespaceDecl>(C))
4157 CurContextIdentifiers.push_back(ND->getIdentifier());
4160 // Add the global context as a NestedNameSpecifier
4161 SpecifierInfo SI = {cast<DeclContext>(Context.getTranslationUnitDecl()),
4162 NestedNameSpecifier::GlobalSpecifier(Context), 1};
4163 DistanceMap[1].push_back(SI);
4166 auto TypoCorrectionConsumer::NamespaceSpecifierSet::buildContextChain(
4167 DeclContext *Start) -> DeclContextList {
4168 assert(Start && "Building a context chain from a null context");
4169 DeclContextList Chain;
4170 for (DeclContext *DC = Start->getPrimaryContext(); DC != nullptr;
4171 DC = DC->getLookupParent()) {
4172 NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(DC);
4173 if (!DC->isInlineNamespace() && !DC->isTransparentContext() &&
4174 !(ND && ND->isAnonymousNamespace()))
4175 Chain.push_back(DC->getPrimaryContext());
4181 TypoCorrectionConsumer::NamespaceSpecifierSet::buildNestedNameSpecifier(
4182 DeclContextList &DeclChain, NestedNameSpecifier *&NNS) {
4183 unsigned NumSpecifiers = 0;
4184 for (DeclContext *C : llvm::reverse(DeclChain)) {
4185 if (auto *ND = dyn_cast_or_null<NamespaceDecl>(C)) {
4186 NNS = NestedNameSpecifier::Create(Context, NNS, ND);
4188 } else if (auto *RD = dyn_cast_or_null<RecordDecl>(C)) {
4189 NNS = NestedNameSpecifier::Create(Context, NNS, RD->isTemplateDecl(),
4190 RD->getTypeForDecl());
4194 return NumSpecifiers;
4197 void TypoCorrectionConsumer::NamespaceSpecifierSet::addNameSpecifier(
4199 NestedNameSpecifier *NNS = nullptr;
4200 unsigned NumSpecifiers = 0;
4201 DeclContextList NamespaceDeclChain(buildContextChain(Ctx));
4202 DeclContextList FullNamespaceDeclChain(NamespaceDeclChain);
4204 // Eliminate common elements from the two DeclContext chains.
4205 for (DeclContext *C : llvm::reverse(CurContextChain)) {
4206 if (NamespaceDeclChain.empty() || NamespaceDeclChain.back() != C)
4208 NamespaceDeclChain.pop_back();
4211 // Build the NestedNameSpecifier from what is left of the NamespaceDeclChain
4212 NumSpecifiers = buildNestedNameSpecifier(NamespaceDeclChain, NNS);
4214 // Add an explicit leading '::' specifier if needed.
4215 if (NamespaceDeclChain.empty()) {
4216 // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
4217 NNS = NestedNameSpecifier::GlobalSpecifier(Context);
4219 buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
4220 } else if (NamedDecl *ND =
4221 dyn_cast_or_null<NamedDecl>(NamespaceDeclChain.back())) {
4222 IdentifierInfo *Name = ND->getIdentifier();
4223 bool SameNameSpecifier = false;
4224 if (std::find(CurNameSpecifierIdentifiers.begin(),
4225 CurNameSpecifierIdentifiers.end(),
4226 Name) != CurNameSpecifierIdentifiers.end()) {
4227 std::string NewNameSpecifier;
4228 llvm::raw_string_ostream SpecifierOStream(NewNameSpecifier);
4229 SmallVector<const IdentifierInfo *, 4> NewNameSpecifierIdentifiers;
4230 getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
4231 NNS->print(SpecifierOStream, Context.getPrintingPolicy());
4232 SpecifierOStream.flush();
4233 SameNameSpecifier = NewNameSpecifier == CurNameSpecifier;
4235 if (SameNameSpecifier ||
4236 std::find(CurContextIdentifiers.begin(), CurContextIdentifiers.end(),
4237 Name) != CurContextIdentifiers.end()) {
4238 // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
4239 NNS = NestedNameSpecifier::GlobalSpecifier(Context);
4241 buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
4245 // If the built NestedNameSpecifier would be replacing an existing
4246 // NestedNameSpecifier, use the number of component identifiers that
4247 // would need to be changed as the edit distance instead of the number
4248 // of components in the built NestedNameSpecifier.
4249 if (NNS && !CurNameSpecifierIdentifiers.empty()) {
4250 SmallVector<const IdentifierInfo*, 4> NewNameSpecifierIdentifiers;
4251 getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
4252 NumSpecifiers = llvm::ComputeEditDistance(
4253 llvm::makeArrayRef(CurNameSpecifierIdentifiers),
4254 llvm::makeArrayRef(NewNameSpecifierIdentifiers));
4257 SpecifierInfo SI = {Ctx, NNS, NumSpecifiers};
4258 DistanceMap[NumSpecifiers].push_back(SI);
4261 /// \brief Perform name lookup for a possible result for typo correction.
4262 static void LookupPotentialTypoResult(Sema &SemaRef,
4264 IdentifierInfo *Name,
4265 Scope *S, CXXScopeSpec *SS,
4266 DeclContext *MemberContext,
4267 bool EnteringContext,
4268 bool isObjCIvarLookup,
4270 Res.suppressDiagnostics();
4272 Res.setLookupName(Name);
4273 Res.setAllowHidden(FindHidden);
4274 if (MemberContext) {
4275 if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(MemberContext)) {
4276 if (isObjCIvarLookup) {
4277 if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(Name)) {
4284 if (ObjCPropertyDecl *Prop = Class->FindPropertyDeclaration(
4285 Name, ObjCPropertyQueryKind::OBJC_PR_query_instance)) {
4292 SemaRef.LookupQualifiedName(Res, MemberContext);
4296 SemaRef.LookupParsedName(Res, S, SS, /*AllowBuiltinCreation=*/false,
4299 // Fake ivar lookup; this should really be part of
4300 // LookupParsedName.
4301 if (ObjCMethodDecl *Method = SemaRef.getCurMethodDecl()) {
4302 if (Method->isInstanceMethod() && Method->getClassInterface() &&
4304 (Res.isSingleResult() &&
4305 Res.getFoundDecl()->isDefinedOutsideFunctionOrMethod()))) {
4306 if (ObjCIvarDecl *IV
4307 = Method->getClassInterface()->lookupInstanceVariable(Name)) {
4315 /// \brief Add keywords to the consumer as possible typo corrections.
4316 static void AddKeywordsToConsumer(Sema &SemaRef,
4317 TypoCorrectionConsumer &Consumer,
4318 Scope *S, CorrectionCandidateCallback &CCC,
4319 bool AfterNestedNameSpecifier) {
4320 if (AfterNestedNameSpecifier) {
4321 // For 'X::', we know exactly which keywords can appear next.
4322 Consumer.addKeywordResult("template");
4323 if (CCC.WantExpressionKeywords)
4324 Consumer.addKeywordResult("operator");
4328 if (CCC.WantObjCSuper)
4329 Consumer.addKeywordResult("super");
4331 if (CCC.WantTypeSpecifiers) {
4332 // Add type-specifier keywords to the set of results.
4333 static const char *const CTypeSpecs[] = {
4334 "char", "const", "double", "enum", "float", "int", "long", "short",
4335 "signed", "struct", "union", "unsigned", "void", "volatile",
4336 "_Complex", "_Imaginary",
4337 // storage-specifiers as well
4338 "extern", "inline", "static", "typedef"
4341 const unsigned NumCTypeSpecs = llvm::array_lengthof(CTypeSpecs);
4342 for (unsigned I = 0; I != NumCTypeSpecs; ++I)
4343 Consumer.addKeywordResult(CTypeSpecs[I]);
4345 if (SemaRef.getLangOpts().C99)
4346 Consumer.addKeywordResult("restrict");
4347 if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus)
4348 Consumer.addKeywordResult("bool");
4349 else if (SemaRef.getLangOpts().C99)
4350 Consumer.addKeywordResult("_Bool");
4352 if (SemaRef.getLangOpts().CPlusPlus) {
4353 Consumer.addKeywordResult("class");
4354 Consumer.addKeywordResult("typename");
4355 Consumer.addKeywordResult("wchar_t");
4357 if (SemaRef.getLangOpts().CPlusPlus11) {
4358 Consumer.addKeywordResult("char16_t");
4359 Consumer.addKeywordResult("char32_t");
4360 Consumer.addKeywordResult("constexpr");
4361 Consumer.addKeywordResult("decltype");
4362 Consumer.addKeywordResult("thread_local");
4366 if (SemaRef.getLangOpts().GNUMode)
4367 Consumer.addKeywordResult("typeof");
4368 } else if (CCC.WantFunctionLikeCasts) {
4369 static const char *const CastableTypeSpecs[] = {
4370 "char", "double", "float", "int", "long", "short",
4371 "signed", "unsigned", "void"
4373 for (auto *kw : CastableTypeSpecs)
4374 Consumer.addKeywordResult(kw);
4377 if (CCC.WantCXXNamedCasts && SemaRef.getLangOpts().CPlusPlus) {
4378 Consumer.addKeywordResult("const_cast");
4379 Consumer.addKeywordResult("dynamic_cast");
4380 Consumer.addKeywordResult("reinterpret_cast");
4381 Consumer.addKeywordResult("static_cast");
4384 if (CCC.WantExpressionKeywords) {
4385 Consumer.addKeywordResult("sizeof");
4386 if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus) {
4387 Consumer.addKeywordResult("false");
4388 Consumer.addKeywordResult("true");
4391 if (SemaRef.getLangOpts().CPlusPlus) {
4392 static const char *const CXXExprs[] = {
4393 "delete", "new", "operator", "throw", "typeid"
4395 const unsigned NumCXXExprs = llvm::array_lengthof(CXXExprs);
4396 for (unsigned I = 0; I != NumCXXExprs; ++I)
4397 Consumer.addKeywordResult(CXXExprs[I]);
4399 if (isa<CXXMethodDecl>(SemaRef.CurContext) &&
4400 cast<CXXMethodDecl>(SemaRef.CurContext)->isInstance())
4401 Consumer.addKeywordResult("this");
4403 if (SemaRef.getLangOpts().CPlusPlus11) {
4404 Consumer.addKeywordResult("alignof");
4405 Consumer.addKeywordResult("nullptr");
4409 if (SemaRef.getLangOpts().C11) {
4410 // FIXME: We should not suggest _Alignof if the alignof macro
4412 Consumer.addKeywordResult("_Alignof");
4416 if (CCC.WantRemainingKeywords) {
4417 if (SemaRef.getCurFunctionOrMethodDecl() || SemaRef.getCurBlock()) {
4419 static const char *const CStmts[] = {
4420 "do", "else", "for", "goto", "if", "return", "switch", "while" };
4421 const unsigned NumCStmts = llvm::array_lengthof(CStmts);
4422 for (unsigned I = 0; I != NumCStmts; ++I)
4423 Consumer.addKeywordResult(CStmts[I]);
4425 if (SemaRef.getLangOpts().CPlusPlus) {
4426 Consumer.addKeywordResult("catch");
4427 Consumer.addKeywordResult("try");
4430 if (S && S->getBreakParent())
4431 Consumer.addKeywordResult("break");
4433 if (S && S->getContinueParent())
4434 Consumer.addKeywordResult("continue");
4436 if (!SemaRef.getCurFunction()->SwitchStack.empty()) {
4437 Consumer.addKeywordResult("case");
4438 Consumer.addKeywordResult("default");
4441 if (SemaRef.getLangOpts().CPlusPlus) {
4442 Consumer.addKeywordResult("namespace");
4443 Consumer.addKeywordResult("template");
4446 if (S && S->isClassScope()) {
4447 Consumer.addKeywordResult("explicit");
4448 Consumer.addKeywordResult("friend");
4449 Consumer.addKeywordResult("mutable");
4450 Consumer.addKeywordResult("private");
4451 Consumer.addKeywordResult("protected");
4452 Consumer.addKeywordResult("public");
4453 Consumer.addKeywordResult("virtual");
4457 if (SemaRef.getLangOpts().CPlusPlus) {
4458 Consumer.addKeywordResult("using");
4460 if (SemaRef.getLangOpts().CPlusPlus11)
4461 Consumer.addKeywordResult("static_assert");
4466 std::unique_ptr<TypoCorrectionConsumer> Sema::makeTypoCorrectionConsumer(
4467 const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
4468 Scope *S, CXXScopeSpec *SS,
4469 std::unique_ptr<CorrectionCandidateCallback> CCC,
4470 DeclContext *MemberContext, bool EnteringContext,
4471 const ObjCObjectPointerType *OPT, bool ErrorRecovery) {
4473 if (Diags.hasFatalErrorOccurred() || !getLangOpts().SpellChecking ||
4474 DisableTypoCorrection)
4477 // In Microsoft mode, don't perform typo correction in a template member
4478 // function dependent context because it interferes with the "lookup into
4479 // dependent bases of class templates" feature.
4480 if (getLangOpts().MSVCCompat && CurContext->isDependentContext() &&
4481 isa<CXXMethodDecl>(CurContext))
4484 // We only attempt to correct typos for identifiers.
4485 IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4489 // If the scope specifier itself was invalid, don't try to correct
4491 if (SS && SS->isInvalid())
4494 // Never try to correct typos during template deduction or
4496 if (!ActiveTemplateInstantiations.empty())
4499 // Don't try to correct 'super'.
4500 if (S && S->isInObjcMethodScope() && Typo == getSuperIdentifier())
4503 // Abort if typo correction already failed for this specific typo.
4504 IdentifierSourceLocations::iterator locs = TypoCorrectionFailures.find(Typo);
4505 if (locs != TypoCorrectionFailures.end() &&
4506 locs->second.count(TypoName.getLoc()))
4509 // Don't try to correct the identifier "vector" when in AltiVec mode.
4510 // TODO: Figure out why typo correction misbehaves in this case, fix it, and
4511 // remove this workaround.
4512 if ((getLangOpts().AltiVec || getLangOpts().ZVector) && Typo->isStr("vector"))
4515 // Provide a stop gap for files that are just seriously broken. Trying
4516 // to correct all typos can turn into a HUGE performance penalty, causing
4517 // some files to take minutes to get rejected by the parser.
4518 unsigned Limit = getDiagnostics().getDiagnosticOptions().SpellCheckingLimit;
4519 if (Limit && TyposCorrected >= Limit)
4523 // If we're handling a missing symbol error, using modules, and the
4524 // special search all modules option is used, look for a missing import.
4525 if (ErrorRecovery && getLangOpts().Modules &&
4526 getLangOpts().ModulesSearchAll) {
4527 // The following has the side effect of loading the missing module.
4528 getModuleLoader().lookupMissingImports(Typo->getName(),
4529 TypoName.getLocStart());
4532 CorrectionCandidateCallback &CCCRef = *CCC;
4533 auto Consumer = llvm::make_unique<TypoCorrectionConsumer>(
4534 *this, TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4537 // Perform name lookup to find visible, similarly-named entities.
4538 bool IsUnqualifiedLookup = false;
4539 DeclContext *QualifiedDC = MemberContext;
4540 if (MemberContext) {
4541 LookupVisibleDecls(MemberContext, LookupKind, *Consumer);
4543 // Look in qualified interfaces.
4545 for (auto *I : OPT->quals())
4546 LookupVisibleDecls(I, LookupKind, *Consumer);
4548 } else if (SS && SS->isSet()) {
4549 QualifiedDC = computeDeclContext(*SS, EnteringContext);
4553 LookupVisibleDecls(QualifiedDC, LookupKind, *Consumer);
4555 IsUnqualifiedLookup = true;
4558 // Determine whether we are going to search in the various namespaces for
4560 bool SearchNamespaces
4561 = getLangOpts().CPlusPlus &&
4562 (IsUnqualifiedLookup || (SS && SS->isSet()));
4564 if (IsUnqualifiedLookup || SearchNamespaces) {
4565 // For unqualified lookup, look through all of the names that we have
4566 // seen in this translation unit.
4567 // FIXME: Re-add the ability to skip very unlikely potential corrections.
4568 for (const auto &I : Context.Idents)
4569 Consumer->FoundName(I.getKey());
4571 // Walk through identifiers in external identifier sources.
4572 // FIXME: Re-add the ability to skip very unlikely potential corrections.
4573 if (IdentifierInfoLookup *External
4574 = Context.Idents.getExternalIdentifierLookup()) {
4575 std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
4577 StringRef Name = Iter->Next();
4581 Consumer->FoundName(Name);
4586 AddKeywordsToConsumer(*this, *Consumer, S, CCCRef, SS && SS->isNotEmpty());
4588 // Build the NestedNameSpecifiers for the KnownNamespaces, if we're going
4589 // to search those namespaces.
4590 if (SearchNamespaces) {
4591 // Load any externally-known namespaces.
4592 if (ExternalSource && !LoadedExternalKnownNamespaces) {
4593 SmallVector<NamespaceDecl *, 4> ExternalKnownNamespaces;
4594 LoadedExternalKnownNamespaces = true;
4595 ExternalSource->ReadKnownNamespaces(ExternalKnownNamespaces);
4596 for (auto *N : ExternalKnownNamespaces)
4597 KnownNamespaces[N] = true;
4600 Consumer->addNamespaces(KnownNamespaces);
4606 /// \brief Try to "correct" a typo in the source code by finding
4607 /// visible declarations whose names are similar to the name that was
4608 /// present in the source code.
4610 /// \param TypoName the \c DeclarationNameInfo structure that contains
4611 /// the name that was present in the source code along with its location.
4613 /// \param LookupKind the name-lookup criteria used to search for the name.
4615 /// \param S the scope in which name lookup occurs.
4617 /// \param SS the nested-name-specifier that precedes the name we're
4618 /// looking for, if present.
4620 /// \param CCC A CorrectionCandidateCallback object that provides further
4621 /// validation of typo correction candidates. It also provides flags for
4622 /// determining the set of keywords permitted.
4624 /// \param MemberContext if non-NULL, the context in which to look for
4625 /// a member access expression.
4627 /// \param EnteringContext whether we're entering the context described by
4628 /// the nested-name-specifier SS.
4630 /// \param OPT when non-NULL, the search for visible declarations will
4631 /// also walk the protocols in the qualified interfaces of \p OPT.
4633 /// \returns a \c TypoCorrection containing the corrected name if the typo
4634 /// along with information such as the \c NamedDecl where the corrected name
4635 /// was declared, and any additional \c NestedNameSpecifier needed to access
4636 /// it (C++ only). The \c TypoCorrection is empty if there is no correction.
4637 TypoCorrection Sema::CorrectTypo(const DeclarationNameInfo &TypoName,
4638 Sema::LookupNameKind LookupKind,
4639 Scope *S, CXXScopeSpec *SS,
4640 std::unique_ptr<CorrectionCandidateCallback> CCC,
4641 CorrectTypoKind Mode,
4642 DeclContext *MemberContext,
4643 bool EnteringContext,
4644 const ObjCObjectPointerType *OPT,
4645 bool RecordFailure) {
4646 assert(CCC && "CorrectTypo requires a CorrectionCandidateCallback");
4648 // Always let the ExternalSource have the first chance at correction, even
4649 // if we would otherwise have given up.
4650 if (ExternalSource) {
4651 if (TypoCorrection Correction = ExternalSource->CorrectTypo(
4652 TypoName, LookupKind, S, SS, *CCC, MemberContext, EnteringContext, OPT))
4656 // Ugly hack equivalent to CTC == CTC_ObjCMessageReceiver;
4657 // WantObjCSuper is only true for CTC_ObjCMessageReceiver and for
4658 // some instances of CTC_Unknown, while WantRemainingKeywords is true
4659 // for CTC_Unknown but not for CTC_ObjCMessageReceiver.
4660 bool ObjCMessageReceiver = CCC->WantObjCSuper && !CCC->WantRemainingKeywords;
4662 IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4663 auto Consumer = makeTypoCorrectionConsumer(
4664 TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4665 EnteringContext, OPT, Mode == CTK_ErrorRecovery);
4668 return TypoCorrection();
4670 // If we haven't found anything, we're done.
4671 if (Consumer->empty())
4672 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4674 // Make sure the best edit distance (prior to adding any namespace qualifiers)
4675 // is not more that about a third of the length of the typo's identifier.
4676 unsigned ED = Consumer->getBestEditDistance(true);
4677 unsigned TypoLen = Typo->getName().size();
4678 if (ED > 0 && TypoLen / ED < 3)
4679 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4681 TypoCorrection BestTC = Consumer->getNextCorrection();
4682 TypoCorrection SecondBestTC = Consumer->getNextCorrection();
4684 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4686 ED = BestTC.getEditDistance();
4688 if (TypoLen >= 3 && ED > 0 && TypoLen / ED < 3) {
4689 // If this was an unqualified lookup and we believe the callback
4690 // object wouldn't have filtered out possible corrections, note
4691 // that no correction was found.
4692 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4695 // If only a single name remains, return that result.
4696 if (!SecondBestTC ||
4697 SecondBestTC.getEditDistance(false) > BestTC.getEditDistance(false)) {
4698 const TypoCorrection &Result = BestTC;
4700 // Don't correct to a keyword that's the same as the typo; the keyword
4701 // wasn't actually in scope.
4702 if (ED == 0 && Result.isKeyword())
4703 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4705 TypoCorrection TC = Result;
4706 TC.setCorrectionRange(SS, TypoName);
4707 checkCorrectionVisibility(*this, TC);
4709 } else if (SecondBestTC && ObjCMessageReceiver) {
4710 // Prefer 'super' when we're completing in a message-receiver
4713 if (BestTC.getCorrection().getAsString() != "super") {
4714 if (SecondBestTC.getCorrection().getAsString() == "super")
4715 BestTC = SecondBestTC;
4716 else if ((*Consumer)["super"].front().isKeyword())
4717 BestTC = (*Consumer)["super"].front();
4719 // Don't correct to a keyword that's the same as the typo; the keyword
4720 // wasn't actually in scope.
4721 if (BestTC.getEditDistance() == 0 ||
4722 BestTC.getCorrection().getAsString() != "super")
4723 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4725 BestTC.setCorrectionRange(SS, TypoName);
4729 // Record the failure's location if needed and return an empty correction. If
4730 // this was an unqualified lookup and we believe the callback object did not
4731 // filter out possible corrections, also cache the failure for the typo.
4732 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure && !SecondBestTC);
4735 /// \brief Try to "correct" a typo in the source code by finding
4736 /// visible declarations whose names are similar to the name that was
4737 /// present in the source code.
4739 /// \param TypoName the \c DeclarationNameInfo structure that contains
4740 /// the name that was present in the source code along with its location.
4742 /// \param LookupKind the name-lookup criteria used to search for the name.
4744 /// \param S the scope in which name lookup occurs.
4746 /// \param SS the nested-name-specifier that precedes the name we're
4747 /// looking for, if present.
4749 /// \param CCC A CorrectionCandidateCallback object that provides further
4750 /// validation of typo correction candidates. It also provides flags for
4751 /// determining the set of keywords permitted.
4753 /// \param TDG A TypoDiagnosticGenerator functor that will be used to print
4754 /// diagnostics when the actual typo correction is attempted.
4756 /// \param TRC A TypoRecoveryCallback functor that will be used to build an
4757 /// Expr from a typo correction candidate.
4759 /// \param MemberContext if non-NULL, the context in which to look for
4760 /// a member access expression.
4762 /// \param EnteringContext whether we're entering the context described by
4763 /// the nested-name-specifier SS.
4765 /// \param OPT when non-NULL, the search for visible declarations will
4766 /// also walk the protocols in the qualified interfaces of \p OPT.
4768 /// \returns a new \c TypoExpr that will later be replaced in the AST with an
4769 /// Expr representing the result of performing typo correction, or nullptr if
4770 /// typo correction is not possible. If nullptr is returned, no diagnostics will
4771 /// be emitted and it is the responsibility of the caller to emit any that are
4773 TypoExpr *Sema::CorrectTypoDelayed(
4774 const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
4775 Scope *S, CXXScopeSpec *SS,
4776 std::unique_ptr<CorrectionCandidateCallback> CCC,
4777 TypoDiagnosticGenerator TDG, TypoRecoveryCallback TRC, CorrectTypoKind Mode,
4778 DeclContext *MemberContext, bool EnteringContext,
4779 const ObjCObjectPointerType *OPT) {
4780 assert(CCC && "CorrectTypoDelayed requires a CorrectionCandidateCallback");
4782 auto Consumer = makeTypoCorrectionConsumer(
4783 TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4784 EnteringContext, OPT, Mode == CTK_ErrorRecovery);
4786 // Give the external sema source a chance to correct the typo.
4787 TypoCorrection ExternalTypo;
4788 if (ExternalSource && Consumer) {
4789 ExternalTypo = ExternalSource->CorrectTypo(
4790 TypoName, LookupKind, S, SS, *Consumer->getCorrectionValidator(),
4791 MemberContext, EnteringContext, OPT);
4793 Consumer->addCorrection(ExternalTypo);
4796 if (!Consumer || Consumer->empty())
4799 // Make sure the best edit distance (prior to adding any namespace qualifiers)
4800 // is not more that about a third of the length of the typo's identifier.
4801 unsigned ED = Consumer->getBestEditDistance(true);
4802 IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4803 if (!ExternalTypo && ED > 0 && Typo->getName().size() / ED < 3)
4806 ExprEvalContexts.back().NumTypos++;
4807 return createDelayedTypo(std::move(Consumer), std::move(TDG), std::move(TRC));
4810 void TypoCorrection::addCorrectionDecl(NamedDecl *CDecl) {
4814 CorrectionDecls.clear();
4816 CorrectionDecls.push_back(CDecl);
4818 if (!CorrectionName)
4819 CorrectionName = CDecl->getDeclName();
4822 std::string TypoCorrection::getAsString(const LangOptions &LO) const {
4823 if (CorrectionNameSpec) {
4824 std::string tmpBuffer;
4825 llvm::raw_string_ostream PrefixOStream(tmpBuffer);
4826 CorrectionNameSpec->print(PrefixOStream, PrintingPolicy(LO));
4827 PrefixOStream << CorrectionName;
4828 return PrefixOStream.str();
4831 return CorrectionName.getAsString();
4834 bool CorrectionCandidateCallback::ValidateCandidate(
4835 const TypoCorrection &candidate) {
4836 if (!candidate.isResolved())
4839 if (candidate.isKeyword())
4840 return WantTypeSpecifiers || WantExpressionKeywords || WantCXXNamedCasts ||
4841 WantRemainingKeywords || WantObjCSuper;
4843 bool HasNonType = false;
4844 bool HasStaticMethod = false;
4845 bool HasNonStaticMethod = false;
4846 for (Decl *D : candidate) {
4847 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(D))
4848 D = FTD->getTemplatedDecl();
4849 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
4850 if (Method->isStatic())
4851 HasStaticMethod = true;
4853 HasNonStaticMethod = true;
4855 if (!isa<TypeDecl>(D))
4859 if (IsAddressOfOperand && HasNonStaticMethod && !HasStaticMethod &&
4860 !candidate.getCorrectionSpecifier())
4863 return WantTypeSpecifiers || HasNonType;
4866 FunctionCallFilterCCC::FunctionCallFilterCCC(Sema &SemaRef, unsigned NumArgs,
4867 bool HasExplicitTemplateArgs,
4869 : NumArgs(NumArgs), HasExplicitTemplateArgs(HasExplicitTemplateArgs),
4870 CurContext(SemaRef.CurContext), MemberFn(ME) {
4871 WantTypeSpecifiers = false;
4872 WantFunctionLikeCasts = SemaRef.getLangOpts().CPlusPlus && NumArgs == 1;
4873 WantRemainingKeywords = false;
4876 bool FunctionCallFilterCCC::ValidateCandidate(const TypoCorrection &candidate) {
4877 if (!candidate.getCorrectionDecl())
4878 return candidate.isKeyword();
4880 for (auto *C : candidate) {
4881 FunctionDecl *FD = nullptr;
4882 NamedDecl *ND = C->getUnderlyingDecl();
4883 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
4884 FD = FTD->getTemplatedDecl();
4885 if (!HasExplicitTemplateArgs && !FD) {
4886 if (!(FD = dyn_cast<FunctionDecl>(ND)) && isa<ValueDecl>(ND)) {
4887 // If the Decl is neither a function nor a template function,
4888 // determine if it is a pointer or reference to a function. If so,
4889 // check against the number of arguments expected for the pointee.
4890 QualType ValType = cast<ValueDecl>(ND)->getType();
4891 if (ValType->isAnyPointerType() || ValType->isReferenceType())
4892 ValType = ValType->getPointeeType();
4893 if (const FunctionProtoType *FPT = ValType->getAs<FunctionProtoType>())
4894 if (FPT->getNumParams() == NumArgs)
4899 // Skip the current candidate if it is not a FunctionDecl or does not accept
4900 // the current number of arguments.
4901 if (!FD || !(FD->getNumParams() >= NumArgs &&
4902 FD->getMinRequiredArguments() <= NumArgs))
4905 // If the current candidate is a non-static C++ method, skip the candidate
4906 // unless the method being corrected--or the current DeclContext, if the
4907 // function being corrected is not a method--is a method in the same class
4908 // or a descendent class of the candidate's parent class.
4909 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
4910 if (MemberFn || !MD->isStatic()) {
4911 CXXMethodDecl *CurMD =
4913 ? dyn_cast_or_null<CXXMethodDecl>(MemberFn->getMemberDecl())
4914 : dyn_cast_or_null<CXXMethodDecl>(CurContext);
4915 CXXRecordDecl *CurRD =
4916 CurMD ? CurMD->getParent()->getCanonicalDecl() : nullptr;
4917 CXXRecordDecl *RD = MD->getParent()->getCanonicalDecl();
4918 if (!CurRD || (CurRD != RD && !CurRD->isDerivedFrom(RD)))
4927 void Sema::diagnoseTypo(const TypoCorrection &Correction,
4928 const PartialDiagnostic &TypoDiag,
4929 bool ErrorRecovery) {
4930 diagnoseTypo(Correction, TypoDiag, PDiag(diag::note_previous_decl),
4934 /// Find which declaration we should import to provide the definition of
4935 /// the given declaration.
4936 static NamedDecl *getDefinitionToImport(NamedDecl *D) {
4937 if (VarDecl *VD = dyn_cast<VarDecl>(D))
4938 return VD->getDefinition();
4939 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
4940 return FD->getDefinition();
4941 if (TagDecl *TD = dyn_cast<TagDecl>(D))
4942 return TD->getDefinition();
4943 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(D))
4944 return ID->getDefinition();
4945 if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl>(D))
4946 return PD->getDefinition();
4947 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
4948 return getDefinitionToImport(TD->getTemplatedDecl());
4952 void Sema::diagnoseMissingImport(SourceLocation Loc, NamedDecl *Decl,
4953 MissingImportKind MIK, bool Recover) {
4954 assert(!isVisible(Decl) && "missing import for non-hidden decl?");
4956 // Suggest importing a module providing the definition of this entity, if
4958 NamedDecl *Def = getDefinitionToImport(Decl);
4962 Module *Owner = getOwningModule(Decl);
4963 assert(Owner && "definition of hidden declaration is not in a module");
4965 llvm::SmallVector<Module*, 8> OwningModules;
4966 OwningModules.push_back(Owner);
4967 auto Merged = Context.getModulesWithMergedDefinition(Decl);
4968 OwningModules.insert(OwningModules.end(), Merged.begin(), Merged.end());
4970 diagnoseMissingImport(Loc, Decl, Decl->getLocation(), OwningModules, MIK,
4974 /// \brief Get a "quoted.h" or <angled.h> include path to use in a diagnostic
4975 /// suggesting the addition of a #include of the specified file.
4976 static std::string getIncludeStringForHeader(Preprocessor &PP,
4977 const FileEntry *E) {
4980 PP.getHeaderSearchInfo().suggestPathToFileForDiagnostics(E, &IsSystem);
4981 return (IsSystem ? '<' : '"') + Path + (IsSystem ? '>' : '"');
4984 void Sema::diagnoseMissingImport(SourceLocation UseLoc, NamedDecl *Decl,
4985 SourceLocation DeclLoc,
4986 ArrayRef<Module *> Modules,
4987 MissingImportKind MIK, bool Recover) {
4988 assert(!Modules.empty());
4990 if (Modules.size() > 1) {
4991 std::string ModuleList;
4993 for (Module *M : Modules) {
4994 ModuleList += "\n ";
4995 if (++N == 5 && N != Modules.size()) {
4996 ModuleList += "[...]";
4999 ModuleList += M->getFullModuleName();
5002 Diag(UseLoc, diag::err_module_unimported_use_multiple)
5003 << (int)MIK << Decl << ModuleList;
5004 } else if (const FileEntry *E =
5005 PP.getModuleHeaderToIncludeForDiagnostics(UseLoc, DeclLoc)) {
5006 // The right way to make the declaration visible is to include a header;
5007 // suggest doing so.
5009 // FIXME: Find a smart place to suggest inserting a #include, and add
5010 // a FixItHint there.
5011 Diag(UseLoc, diag::err_module_unimported_use_header)
5012 << (int)MIK << Decl << Modules[0]->getFullModuleName()
5013 << getIncludeStringForHeader(PP, E);
5015 // FIXME: Add a FixItHint that imports the corresponding module.
5016 Diag(UseLoc, diag::err_module_unimported_use)
5017 << (int)MIK << Decl << Modules[0]->getFullModuleName();
5022 case MissingImportKind::Declaration:
5023 DiagID = diag::note_previous_declaration;
5025 case MissingImportKind::Definition:
5026 DiagID = diag::note_previous_definition;
5028 case MissingImportKind::DefaultArgument:
5029 DiagID = diag::note_default_argument_declared_here;
5031 case MissingImportKind::ExplicitSpecialization:
5032 DiagID = diag::note_explicit_specialization_declared_here;
5034 case MissingImportKind::PartialSpecialization:
5035 DiagID = diag::note_partial_specialization_declared_here;
5038 Diag(DeclLoc, DiagID);
5040 // Try to recover by implicitly importing this module.
5042 createImplicitModuleImportForErrorRecovery(UseLoc, Modules[0]);
5045 /// \brief Diagnose a successfully-corrected typo. Separated from the correction
5046 /// itself to allow external validation of the result, etc.
5048 /// \param Correction The result of performing typo correction.
5049 /// \param TypoDiag The diagnostic to produce. This will have the corrected
5050 /// string added to it (and usually also a fixit).
5051 /// \param PrevNote A note to use when indicating the location of the entity to
5052 /// which we are correcting. Will have the correction string added to it.
5053 /// \param ErrorRecovery If \c true (the default), the caller is going to
5054 /// recover from the typo as if the corrected string had been typed.
5055 /// In this case, \c PDiag must be an error, and we will attach a fixit
5057 void Sema::diagnoseTypo(const TypoCorrection &Correction,
5058 const PartialDiagnostic &TypoDiag,
5059 const PartialDiagnostic &PrevNote,
5060 bool ErrorRecovery) {
5061 std::string CorrectedStr = Correction.getAsString(getLangOpts());
5062 std::string CorrectedQuotedStr = Correction.getQuoted(getLangOpts());
5063 FixItHint FixTypo = FixItHint::CreateReplacement(
5064 Correction.getCorrectionRange(), CorrectedStr);
5066 // Maybe we're just missing a module import.
5067 if (Correction.requiresImport()) {
5068 NamedDecl *Decl = Correction.getFoundDecl();
5069 assert(Decl && "import required but no declaration to import");
5071 diagnoseMissingImport(Correction.getCorrectionRange().getBegin(), Decl,
5072 MissingImportKind::Declaration, ErrorRecovery);
5076 Diag(Correction.getCorrectionRange().getBegin(), TypoDiag)
5077 << CorrectedQuotedStr << (ErrorRecovery ? FixTypo : FixItHint());
5079 NamedDecl *ChosenDecl =
5080 Correction.isKeyword() ? nullptr : Correction.getFoundDecl();
5081 if (PrevNote.getDiagID() && ChosenDecl)
5082 Diag(ChosenDecl->getLocation(), PrevNote)
5083 << CorrectedQuotedStr << (ErrorRecovery ? FixItHint() : FixTypo);
5086 TypoExpr *Sema::createDelayedTypo(std::unique_ptr<TypoCorrectionConsumer> TCC,
5087 TypoDiagnosticGenerator TDG,
5088 TypoRecoveryCallback TRC) {
5089 assert(TCC && "createDelayedTypo requires a valid TypoCorrectionConsumer");
5090 auto TE = new (Context) TypoExpr(Context.DependentTy);
5091 auto &State = DelayedTypos[TE];
5092 State.Consumer = std::move(TCC);
5093 State.DiagHandler = std::move(TDG);
5094 State.RecoveryHandler = std::move(TRC);
5098 const Sema::TypoExprState &Sema::getTypoExprState(TypoExpr *TE) const {
5099 auto Entry = DelayedTypos.find(TE);
5100 assert(Entry != DelayedTypos.end() &&
5101 "Failed to get the state for a TypoExpr!");
5102 return Entry->second;
5105 void Sema::clearDelayedTypo(TypoExpr *TE) {
5106 DelayedTypos.erase(TE);
5109 void Sema::ActOnPragmaDump(Scope *S, SourceLocation IILoc, IdentifierInfo *II) {
5110 DeclarationNameInfo Name(II, IILoc);
5111 LookupResult R(*this, Name, LookupAnyName, Sema::NotForRedeclaration);
5112 R.suppressDiagnostics();
5113 R.setHideTags(false);