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/AST/ASTContext.h"
16 #include "clang/AST/CXXInheritance.h"
17 #include "clang/AST/Decl.h"
18 #include "clang/AST/DeclCXX.h"
19 #include "clang/AST/DeclLookups.h"
20 #include "clang/AST/DeclObjC.h"
21 #include "clang/AST/DeclTemplate.h"
22 #include "clang/AST/Expr.h"
23 #include "clang/AST/ExprCXX.h"
24 #include "clang/Basic/Builtins.h"
25 #include "clang/Basic/LangOptions.h"
26 #include "clang/Lex/HeaderSearch.h"
27 #include "clang/Lex/ModuleLoader.h"
28 #include "clang/Lex/Preprocessor.h"
29 #include "clang/Sema/DeclSpec.h"
30 #include "clang/Sema/Lookup.h"
31 #include "clang/Sema/Overload.h"
32 #include "clang/Sema/Scope.h"
33 #include "clang/Sema/ScopeInfo.h"
34 #include "clang/Sema/Sema.h"
35 #include "clang/Sema/SemaInternal.h"
36 #include "clang/Sema/TemplateDeduction.h"
37 #include "clang/Sema/TypoCorrection.h"
38 #include "llvm/ADT/STLExtras.h"
39 #include "llvm/ADT/SmallPtrSet.h"
40 #include "llvm/ADT/TinyPtrVector.h"
41 #include "llvm/ADT/edit_distance.h"
42 #include "llvm/Support/ErrorHandling.h"
50 using namespace clang;
54 class UnqualUsingEntry {
55 const DeclContext *Nominated;
56 const DeclContext *CommonAncestor;
59 UnqualUsingEntry(const DeclContext *Nominated,
60 const DeclContext *CommonAncestor)
61 : Nominated(Nominated), CommonAncestor(CommonAncestor) {
64 const DeclContext *getCommonAncestor() const {
65 return CommonAncestor;
68 const DeclContext *getNominatedNamespace() const {
72 // Sort by the pointer value of the common ancestor.
74 bool operator()(const UnqualUsingEntry &L, const UnqualUsingEntry &R) {
75 return L.getCommonAncestor() < R.getCommonAncestor();
78 bool operator()(const UnqualUsingEntry &E, const DeclContext *DC) {
79 return E.getCommonAncestor() < DC;
82 bool operator()(const DeclContext *DC, const UnqualUsingEntry &E) {
83 return DC < E.getCommonAncestor();
88 /// A collection of using directives, as used by C++ unqualified
90 class UnqualUsingDirectiveSet {
91 typedef SmallVector<UnqualUsingEntry, 8> ListTy;
94 llvm::SmallPtrSet<DeclContext*, 8> visited;
97 UnqualUsingDirectiveSet() {}
99 void visitScopeChain(Scope *S, Scope *InnermostFileScope) {
100 // C++ [namespace.udir]p1:
101 // During unqualified name lookup, the names appear as if they
102 // were declared in the nearest enclosing namespace which contains
103 // both the using-directive and the nominated namespace.
104 DeclContext *InnermostFileDC = InnermostFileScope->getEntity();
105 assert(InnermostFileDC && InnermostFileDC->isFileContext());
107 for (; S; S = S->getParent()) {
108 // C++ [namespace.udir]p1:
109 // A using-directive shall not appear in class scope, but may
110 // appear in namespace scope or in block scope.
111 DeclContext *Ctx = S->getEntity();
112 if (Ctx && Ctx->isFileContext()) {
114 } else if (!Ctx || Ctx->isFunctionOrMethod()) {
115 for (auto *I : S->using_directives())
116 visit(I, InnermostFileDC);
121 // Visits a context and collect all of its using directives
122 // recursively. Treats all using directives as if they were
123 // declared in the context.
125 // A given context is only every visited once, so it is important
126 // that contexts be visited from the inside out in order to get
127 // the effective DCs right.
128 void visit(DeclContext *DC, DeclContext *EffectiveDC) {
129 if (!visited.insert(DC).second)
132 addUsingDirectives(DC, EffectiveDC);
135 // Visits a using directive and collects all of its using
136 // directives recursively. Treats all using directives as if they
137 // were declared in the effective DC.
138 void visit(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) {
139 DeclContext *NS = UD->getNominatedNamespace();
140 if (!visited.insert(NS).second)
143 addUsingDirective(UD, EffectiveDC);
144 addUsingDirectives(NS, EffectiveDC);
147 // Adds all the using directives in a context (and those nominated
148 // by its using directives, transitively) as if they appeared in
149 // the given effective context.
150 void addUsingDirectives(DeclContext *DC, DeclContext *EffectiveDC) {
151 SmallVector<DeclContext*, 4> queue;
153 for (auto UD : DC->using_directives()) {
154 DeclContext *NS = UD->getNominatedNamespace();
155 if (visited.insert(NS).second) {
156 addUsingDirective(UD, EffectiveDC);
164 DC = queue.pop_back_val();
168 // Add a using directive as if it had been declared in the given
169 // context. This helps implement C++ [namespace.udir]p3:
170 // The using-directive is transitive: if a scope contains a
171 // using-directive that nominates a second namespace that itself
172 // contains using-directives, the effect is as if the
173 // using-directives from the second namespace also appeared in
175 void addUsingDirective(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) {
176 // Find the common ancestor between the effective context and
177 // the nominated namespace.
178 DeclContext *Common = UD->getNominatedNamespace();
179 while (!Common->Encloses(EffectiveDC))
180 Common = Common->getParent();
181 Common = Common->getPrimaryContext();
183 list.push_back(UnqualUsingEntry(UD->getNominatedNamespace(), Common));
187 std::sort(list.begin(), list.end(), UnqualUsingEntry::Comparator());
190 typedef ListTy::const_iterator const_iterator;
192 const_iterator begin() const { return list.begin(); }
193 const_iterator end() const { return list.end(); }
195 llvm::iterator_range<const_iterator>
196 getNamespacesFor(DeclContext *DC) const {
197 return llvm::make_range(std::equal_range(begin(), end(),
198 DC->getPrimaryContext(),
199 UnqualUsingEntry::Comparator()));
202 } // end anonymous namespace
204 // Retrieve the set of identifier namespaces that correspond to a
205 // specific kind of name lookup.
206 static inline unsigned getIDNS(Sema::LookupNameKind NameKind,
208 bool Redeclaration) {
211 case Sema::LookupObjCImplicitSelfParam:
212 case Sema::LookupOrdinaryName:
213 case Sema::LookupRedeclarationWithLinkage:
214 case Sema::LookupLocalFriendName:
215 IDNS = Decl::IDNS_Ordinary;
217 IDNS |= Decl::IDNS_Tag | Decl::IDNS_Member | Decl::IDNS_Namespace;
219 IDNS |= Decl::IDNS_TagFriend | Decl::IDNS_OrdinaryFriend;
222 IDNS |= Decl::IDNS_LocalExtern;
225 case Sema::LookupOperatorName:
226 // Operator lookup is its own crazy thing; it is not the same
227 // as (e.g.) looking up an operator name for redeclaration.
228 assert(!Redeclaration && "cannot do redeclaration operator lookup");
229 IDNS = Decl::IDNS_NonMemberOperator;
232 case Sema::LookupTagName:
234 IDNS = Decl::IDNS_Type;
236 // When looking for a redeclaration of a tag name, we add:
237 // 1) TagFriend to find undeclared friend decls
238 // 2) Namespace because they can't "overload" with tag decls.
239 // 3) Tag because it includes class templates, which can't
240 // "overload" with tag decls.
242 IDNS |= Decl::IDNS_Tag | Decl::IDNS_TagFriend | Decl::IDNS_Namespace;
244 IDNS = Decl::IDNS_Tag;
248 case Sema::LookupLabel:
249 IDNS = Decl::IDNS_Label;
252 case Sema::LookupMemberName:
253 IDNS = Decl::IDNS_Member;
255 IDNS |= Decl::IDNS_Tag | Decl::IDNS_Ordinary;
258 case Sema::LookupNestedNameSpecifierName:
259 IDNS = Decl::IDNS_Type | Decl::IDNS_Namespace;
262 case Sema::LookupNamespaceName:
263 IDNS = Decl::IDNS_Namespace;
266 case Sema::LookupUsingDeclName:
267 assert(Redeclaration && "should only be used for redecl lookup");
268 IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag | Decl::IDNS_Member |
269 Decl::IDNS_Using | Decl::IDNS_TagFriend | Decl::IDNS_OrdinaryFriend |
270 Decl::IDNS_LocalExtern;
273 case Sema::LookupObjCProtocolName:
274 IDNS = Decl::IDNS_ObjCProtocol;
277 case Sema::LookupOMPReductionName:
278 IDNS = Decl::IDNS_OMPReduction;
281 case Sema::LookupAnyName:
282 IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag | Decl::IDNS_Member
283 | Decl::IDNS_Using | Decl::IDNS_Namespace | Decl::IDNS_ObjCProtocol
290 void LookupResult::configure() {
291 IDNS = getIDNS(LookupKind, getSema().getLangOpts().CPlusPlus,
292 isForRedeclaration());
294 // If we're looking for one of the allocation or deallocation
295 // operators, make sure that the implicitly-declared new and delete
296 // operators can be found.
297 switch (NameInfo.getName().getCXXOverloadedOperator()) {
301 case OO_Array_Delete:
302 getSema().DeclareGlobalNewDelete();
309 // Compiler builtins are always visible, regardless of where they end
310 // up being declared.
311 if (IdentifierInfo *Id = NameInfo.getName().getAsIdentifierInfo()) {
312 if (unsigned BuiltinID = Id->getBuiltinID()) {
313 if (!getSema().Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
319 bool LookupResult::sanity() const {
320 // This function is never called by NDEBUG builds.
321 assert(ResultKind != NotFound || Decls.size() == 0);
322 assert(ResultKind != Found || Decls.size() == 1);
323 assert(ResultKind != FoundOverloaded || Decls.size() > 1 ||
324 (Decls.size() == 1 &&
325 isa<FunctionTemplateDecl>((*begin())->getUnderlyingDecl())));
326 assert(ResultKind != FoundUnresolvedValue || sanityCheckUnresolved());
327 assert(ResultKind != Ambiguous || Decls.size() > 1 ||
328 (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects ||
329 Ambiguity == AmbiguousBaseSubobjectTypes)));
330 assert((Paths != nullptr) == (ResultKind == Ambiguous &&
331 (Ambiguity == AmbiguousBaseSubobjectTypes ||
332 Ambiguity == AmbiguousBaseSubobjects)));
336 // Necessary because CXXBasePaths is not complete in Sema.h
337 void LookupResult::deletePaths(CXXBasePaths *Paths) {
341 /// Get a representative context for a declaration such that two declarations
342 /// will have the same context if they were found within the same scope.
343 static DeclContext *getContextForScopeMatching(Decl *D) {
344 // For function-local declarations, use that function as the context. This
345 // doesn't account for scopes within the function; the caller must deal with
347 DeclContext *DC = D->getLexicalDeclContext();
348 if (DC->isFunctionOrMethod())
351 // Otherwise, look at the semantic context of the declaration. The
352 // declaration must have been found there.
353 return D->getDeclContext()->getRedeclContext();
356 /// \brief Determine whether \p D is a better lookup result than \p Existing,
357 /// given that they declare the same entity.
358 static bool isPreferredLookupResult(Sema &S, Sema::LookupNameKind Kind,
359 NamedDecl *D, NamedDecl *Existing) {
360 // When looking up redeclarations of a using declaration, prefer a using
361 // shadow declaration over any other declaration of the same entity.
362 if (Kind == Sema::LookupUsingDeclName && isa<UsingShadowDecl>(D) &&
363 !isa<UsingShadowDecl>(Existing))
366 auto *DUnderlying = D->getUnderlyingDecl();
367 auto *EUnderlying = Existing->getUnderlyingDecl();
369 // If they have different underlying declarations, prefer a typedef over the
370 // original type (this happens when two type declarations denote the same
371 // type), per a generous reading of C++ [dcl.typedef]p3 and p4. The typedef
372 // might carry additional semantic information, such as an alignment override.
373 // However, per C++ [dcl.typedef]p5, when looking up a tag name, prefer a tag
374 // declaration over a typedef.
375 if (DUnderlying->getCanonicalDecl() != EUnderlying->getCanonicalDecl()) {
376 assert(isa<TypeDecl>(DUnderlying) && isa<TypeDecl>(EUnderlying));
377 bool HaveTag = isa<TagDecl>(EUnderlying);
378 bool WantTag = Kind == Sema::LookupTagName;
379 return HaveTag != WantTag;
382 // Pick the function with more default arguments.
383 // FIXME: In the presence of ambiguous default arguments, we should keep both,
384 // so we can diagnose the ambiguity if the default argument is needed.
385 // See C++ [over.match.best]p3.
386 if (auto *DFD = dyn_cast<FunctionDecl>(DUnderlying)) {
387 auto *EFD = cast<FunctionDecl>(EUnderlying);
388 unsigned DMin = DFD->getMinRequiredArguments();
389 unsigned EMin = EFD->getMinRequiredArguments();
390 // If D has more default arguments, it is preferred.
393 // FIXME: When we track visibility for default function arguments, check
394 // that we pick the declaration with more visible default arguments.
397 // Pick the template with more default template arguments.
398 if (auto *DTD = dyn_cast<TemplateDecl>(DUnderlying)) {
399 auto *ETD = cast<TemplateDecl>(EUnderlying);
400 unsigned DMin = DTD->getTemplateParameters()->getMinRequiredArguments();
401 unsigned EMin = ETD->getTemplateParameters()->getMinRequiredArguments();
402 // If D has more default arguments, it is preferred. Note that default
403 // arguments (and their visibility) is monotonically increasing across the
404 // redeclaration chain, so this is a quick proxy for "is more recent".
407 // If D has more *visible* default arguments, it is preferred. Note, an
408 // earlier default argument being visible does not imply that a later
409 // default argument is visible, so we can't just check the first one.
410 for (unsigned I = DMin, N = DTD->getTemplateParameters()->size();
412 if (!S.hasVisibleDefaultArgument(
413 ETD->getTemplateParameters()->getParam(I)) &&
414 S.hasVisibleDefaultArgument(
415 DTD->getTemplateParameters()->getParam(I)))
420 // VarDecl can have incomplete array types, prefer the one with more complete
422 if (VarDecl *DVD = dyn_cast<VarDecl>(DUnderlying)) {
423 VarDecl *EVD = cast<VarDecl>(EUnderlying);
424 if (EVD->getType()->isIncompleteType() &&
425 !DVD->getType()->isIncompleteType()) {
426 // Prefer the decl with a more complete type if visible.
427 return S.isVisible(DVD);
429 return false; // Avoid picking up a newer decl, just because it was newer.
432 // For most kinds of declaration, it doesn't really matter which one we pick.
433 if (!isa<FunctionDecl>(DUnderlying) && !isa<VarDecl>(DUnderlying)) {
434 // If the existing declaration is hidden, prefer the new one. Otherwise,
435 // keep what we've got.
436 return !S.isVisible(Existing);
439 // Pick the newer declaration; it might have a more precise type.
440 for (Decl *Prev = DUnderlying->getPreviousDecl(); Prev;
441 Prev = Prev->getPreviousDecl())
442 if (Prev == EUnderlying)
447 /// Determine whether \p D can hide a tag declaration.
448 static bool canHideTag(NamedDecl *D) {
449 // C++ [basic.scope.declarative]p4:
450 // Given a set of declarations in a single declarative region [...]
451 // exactly one declaration shall declare a class name or enumeration name
452 // that is not a typedef name and the other declarations shall all refer to
453 // the same variable, non-static data member, or enumerator, or all refer
454 // to functions and function templates; in this case the class name or
455 // enumeration name is hidden.
456 // C++ [basic.scope.hiding]p2:
457 // A class name or enumeration name can be hidden by the name of a
458 // variable, data member, function, or enumerator declared in the same
460 // An UnresolvedUsingValueDecl always instantiates to one of these.
461 D = D->getUnderlyingDecl();
462 return isa<VarDecl>(D) || isa<EnumConstantDecl>(D) || isa<FunctionDecl>(D) ||
463 isa<FunctionTemplateDecl>(D) || isa<FieldDecl>(D) ||
464 isa<UnresolvedUsingValueDecl>(D);
467 /// Resolves the result kind of this lookup.
468 void LookupResult::resolveKind() {
469 unsigned N = Decls.size();
471 // Fast case: no possible ambiguity.
473 assert(ResultKind == NotFound ||
474 ResultKind == NotFoundInCurrentInstantiation);
478 // If there's a single decl, we need to examine it to decide what
479 // kind of lookup this is.
481 NamedDecl *D = (*Decls.begin())->getUnderlyingDecl();
482 if (isa<FunctionTemplateDecl>(D))
483 ResultKind = FoundOverloaded;
484 else if (isa<UnresolvedUsingValueDecl>(D))
485 ResultKind = FoundUnresolvedValue;
489 // Don't do any extra resolution if we've already resolved as ambiguous.
490 if (ResultKind == Ambiguous) return;
492 llvm::SmallDenseMap<NamedDecl*, unsigned, 16> Unique;
493 llvm::SmallDenseMap<QualType, unsigned, 16> UniqueTypes;
495 bool Ambiguous = false;
496 bool HasTag = false, HasFunction = false;
497 bool HasFunctionTemplate = false, HasUnresolved = false;
498 NamedDecl *HasNonFunction = nullptr;
500 llvm::SmallVector<NamedDecl*, 4> EquivalentNonFunctions;
502 unsigned UniqueTagIndex = 0;
506 NamedDecl *D = Decls[I]->getUnderlyingDecl();
507 D = cast<NamedDecl>(D->getCanonicalDecl());
509 // Ignore an invalid declaration unless it's the only one left.
510 if (D->isInvalidDecl() && !(I == 0 && N == 1)) {
511 Decls[I] = Decls[--N];
515 llvm::Optional<unsigned> ExistingI;
517 // Redeclarations of types via typedef can occur both within a scope
518 // and, through using declarations and directives, across scopes. There is
519 // no ambiguity if they all refer to the same type, so unique based on the
521 if (TypeDecl *TD = dyn_cast<TypeDecl>(D)) {
522 QualType T = getSema().Context.getTypeDeclType(TD);
523 auto UniqueResult = UniqueTypes.insert(
524 std::make_pair(getSema().Context.getCanonicalType(T), I));
525 if (!UniqueResult.second) {
526 // The type is not unique.
527 ExistingI = UniqueResult.first->second;
531 // For non-type declarations, check for a prior lookup result naming this
532 // canonical declaration.
534 auto UniqueResult = Unique.insert(std::make_pair(D, I));
535 if (!UniqueResult.second) {
536 // We've seen this entity before.
537 ExistingI = UniqueResult.first->second;
542 // This is not a unique lookup result. Pick one of the results and
543 // discard the other.
544 if (isPreferredLookupResult(getSema(), getLookupKind(), Decls[I],
546 Decls[*ExistingI] = Decls[I];
547 Decls[I] = Decls[--N];
551 // Otherwise, do some decl type analysis and then continue.
553 if (isa<UnresolvedUsingValueDecl>(D)) {
554 HasUnresolved = true;
555 } else if (isa<TagDecl>(D)) {
560 } else if (isa<FunctionTemplateDecl>(D)) {
562 HasFunctionTemplate = true;
563 } else if (isa<FunctionDecl>(D)) {
566 if (HasNonFunction) {
567 // If we're about to create an ambiguity between two declarations that
568 // are equivalent, but one is an internal linkage declaration from one
569 // module and the other is an internal linkage declaration from another
570 // module, just skip it.
571 if (getSema().isEquivalentInternalLinkageDeclaration(HasNonFunction,
573 EquivalentNonFunctions.push_back(D);
574 Decls[I] = Decls[--N];
585 // C++ [basic.scope.hiding]p2:
586 // A class name or enumeration name can be hidden by the name of
587 // an object, function, or enumerator declared in the same
588 // scope. If a class or enumeration name and an object, function,
589 // or enumerator are declared in the same scope (in any order)
590 // with the same name, the class or enumeration name is hidden
591 // wherever the object, function, or enumerator name is visible.
592 // But it's still an error if there are distinct tag types found,
593 // even if they're not visible. (ref?)
594 if (N > 1 && HideTags && HasTag && !Ambiguous &&
595 (HasFunction || HasNonFunction || HasUnresolved)) {
596 NamedDecl *OtherDecl = Decls[UniqueTagIndex ? 0 : N - 1];
597 if (isa<TagDecl>(Decls[UniqueTagIndex]->getUnderlyingDecl()) &&
598 getContextForScopeMatching(Decls[UniqueTagIndex])->Equals(
599 getContextForScopeMatching(OtherDecl)) &&
600 canHideTag(OtherDecl))
601 Decls[UniqueTagIndex] = Decls[--N];
606 // FIXME: This diagnostic should really be delayed until we're done with
607 // the lookup result, in case the ambiguity is resolved by the caller.
608 if (!EquivalentNonFunctions.empty() && !Ambiguous)
609 getSema().diagnoseEquivalentInternalLinkageDeclarations(
610 getNameLoc(), HasNonFunction, EquivalentNonFunctions);
614 if (HasNonFunction && (HasFunction || HasUnresolved))
618 setAmbiguous(LookupResult::AmbiguousReference);
619 else if (HasUnresolved)
620 ResultKind = LookupResult::FoundUnresolvedValue;
621 else if (N > 1 || HasFunctionTemplate)
622 ResultKind = LookupResult::FoundOverloaded;
624 ResultKind = LookupResult::Found;
627 void LookupResult::addDeclsFromBasePaths(const CXXBasePaths &P) {
628 CXXBasePaths::const_paths_iterator I, E;
629 for (I = P.begin(), E = P.end(); I != E; ++I)
630 for (DeclContext::lookup_iterator DI = I->Decls.begin(),
631 DE = I->Decls.end(); DI != DE; ++DI)
635 void LookupResult::setAmbiguousBaseSubobjects(CXXBasePaths &P) {
636 Paths = new CXXBasePaths;
638 addDeclsFromBasePaths(*Paths);
640 setAmbiguous(AmbiguousBaseSubobjects);
643 void LookupResult::setAmbiguousBaseSubobjectTypes(CXXBasePaths &P) {
644 Paths = new CXXBasePaths;
646 addDeclsFromBasePaths(*Paths);
648 setAmbiguous(AmbiguousBaseSubobjectTypes);
651 void LookupResult::print(raw_ostream &Out) {
652 Out << Decls.size() << " result(s)";
653 if (isAmbiguous()) Out << ", ambiguous";
654 if (Paths) Out << ", base paths present";
656 for (iterator I = begin(), E = end(); I != E; ++I) {
662 LLVM_DUMP_METHOD void LookupResult::dump() {
663 llvm::errs() << "lookup results for " << getLookupName().getAsString()
665 for (NamedDecl *D : *this)
669 /// \brief Lookup a builtin function, when name lookup would otherwise
671 static bool LookupBuiltin(Sema &S, LookupResult &R) {
672 Sema::LookupNameKind NameKind = R.getLookupKind();
674 // If we didn't find a use of this identifier, and if the identifier
675 // corresponds to a compiler builtin, create the decl object for the builtin
676 // now, injecting it into translation unit scope, and return it.
677 if (NameKind == Sema::LookupOrdinaryName ||
678 NameKind == Sema::LookupRedeclarationWithLinkage) {
679 IdentifierInfo *II = R.getLookupName().getAsIdentifierInfo();
681 if (S.getLangOpts().CPlusPlus && NameKind == Sema::LookupOrdinaryName) {
682 if (II == S.getASTContext().getMakeIntegerSeqName()) {
683 R.addDecl(S.getASTContext().getMakeIntegerSeqDecl());
685 } else if (II == S.getASTContext().getTypePackElementName()) {
686 R.addDecl(S.getASTContext().getTypePackElementDecl());
691 // If this is a builtin on this (or all) targets, create the decl.
692 if (unsigned BuiltinID = II->getBuiltinID()) {
693 // In C++ and OpenCL (spec v1.2 s6.9.f), we don't have any predefined
694 // library functions like 'malloc'. Instead, we'll just error.
695 if ((S.getLangOpts().CPlusPlus || S.getLangOpts().OpenCL) &&
696 S.Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
699 if (NamedDecl *D = S.LazilyCreateBuiltin((IdentifierInfo *)II,
700 BuiltinID, S.TUScope,
701 R.isForRedeclaration(),
713 /// \brief Determine whether we can declare a special member function within
714 /// the class at this point.
715 static bool CanDeclareSpecialMemberFunction(const CXXRecordDecl *Class) {
716 // We need to have a definition for the class.
717 if (!Class->getDefinition() || Class->isDependentContext())
720 // We can't be in the middle of defining the class.
721 return !Class->isBeingDefined();
724 void Sema::ForceDeclarationOfImplicitMembers(CXXRecordDecl *Class) {
725 if (!CanDeclareSpecialMemberFunction(Class))
728 // If the default constructor has not yet been declared, do so now.
729 if (Class->needsImplicitDefaultConstructor())
730 DeclareImplicitDefaultConstructor(Class);
732 // If the copy constructor has not yet been declared, do so now.
733 if (Class->needsImplicitCopyConstructor())
734 DeclareImplicitCopyConstructor(Class);
736 // If the copy assignment operator has not yet been declared, do so now.
737 if (Class->needsImplicitCopyAssignment())
738 DeclareImplicitCopyAssignment(Class);
740 if (getLangOpts().CPlusPlus11) {
741 // If the move constructor has not yet been declared, do so now.
742 if (Class->needsImplicitMoveConstructor())
743 DeclareImplicitMoveConstructor(Class);
745 // If the move assignment operator has not yet been declared, do so now.
746 if (Class->needsImplicitMoveAssignment())
747 DeclareImplicitMoveAssignment(Class);
750 // If the destructor has not yet been declared, do so now.
751 if (Class->needsImplicitDestructor())
752 DeclareImplicitDestructor(Class);
755 /// \brief Determine whether this is the name of an implicitly-declared
756 /// special member function.
757 static bool isImplicitlyDeclaredMemberFunctionName(DeclarationName Name) {
758 switch (Name.getNameKind()) {
759 case DeclarationName::CXXConstructorName:
760 case DeclarationName::CXXDestructorName:
763 case DeclarationName::CXXOperatorName:
764 return Name.getCXXOverloadedOperator() == OO_Equal;
773 /// \brief If there are any implicit member functions with the given name
774 /// that need to be declared in the given declaration context, do so.
775 static void DeclareImplicitMemberFunctionsWithName(Sema &S,
776 DeclarationName Name,
777 const DeclContext *DC) {
781 switch (Name.getNameKind()) {
782 case DeclarationName::CXXConstructorName:
783 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
784 if (Record->getDefinition() && CanDeclareSpecialMemberFunction(Record)) {
785 CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record);
786 if (Record->needsImplicitDefaultConstructor())
787 S.DeclareImplicitDefaultConstructor(Class);
788 if (Record->needsImplicitCopyConstructor())
789 S.DeclareImplicitCopyConstructor(Class);
790 if (S.getLangOpts().CPlusPlus11 &&
791 Record->needsImplicitMoveConstructor())
792 S.DeclareImplicitMoveConstructor(Class);
796 case DeclarationName::CXXDestructorName:
797 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
798 if (Record->getDefinition() && Record->needsImplicitDestructor() &&
799 CanDeclareSpecialMemberFunction(Record))
800 S.DeclareImplicitDestructor(const_cast<CXXRecordDecl *>(Record));
803 case DeclarationName::CXXOperatorName:
804 if (Name.getCXXOverloadedOperator() != OO_Equal)
807 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) {
808 if (Record->getDefinition() && CanDeclareSpecialMemberFunction(Record)) {
809 CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record);
810 if (Record->needsImplicitCopyAssignment())
811 S.DeclareImplicitCopyAssignment(Class);
812 if (S.getLangOpts().CPlusPlus11 &&
813 Record->needsImplicitMoveAssignment())
814 S.DeclareImplicitMoveAssignment(Class);
824 // Adds all qualifying matches for a name within a decl context to the
825 // given lookup result. Returns true if any matches were found.
826 static bool LookupDirect(Sema &S, LookupResult &R, const DeclContext *DC) {
829 // Lazily declare C++ special member functions.
830 if (S.getLangOpts().CPlusPlus)
831 DeclareImplicitMemberFunctionsWithName(S, R.getLookupName(), DC);
833 // Perform lookup into this declaration context.
834 DeclContext::lookup_result DR = DC->lookup(R.getLookupName());
835 for (DeclContext::lookup_iterator I = DR.begin(), E = DR.end(); I != E;
838 if ((D = R.getAcceptableDecl(D))) {
844 if (!Found && DC->isTranslationUnit() && LookupBuiltin(S, R))
847 if (R.getLookupName().getNameKind()
848 != DeclarationName::CXXConversionFunctionName ||
849 R.getLookupName().getCXXNameType()->isDependentType() ||
850 !isa<CXXRecordDecl>(DC))
854 // A specialization of a conversion function template is not found by
855 // name lookup. Instead, any conversion function templates visible in the
856 // context of the use are considered. [...]
857 const CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
858 if (!Record->isCompleteDefinition())
861 for (CXXRecordDecl::conversion_iterator U = Record->conversion_begin(),
862 UEnd = Record->conversion_end(); U != UEnd; ++U) {
863 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(*U);
867 // When we're performing lookup for the purposes of redeclaration, just
868 // add the conversion function template. When we deduce template
869 // arguments for specializations, we'll end up unifying the return
870 // type of the new declaration with the type of the function template.
871 if (R.isForRedeclaration()) {
872 R.addDecl(ConvTemplate);
878 // [...] For each such operator, if argument deduction succeeds
879 // (14.9.2.3), the resulting specialization is used as if found by
882 // When referencing a conversion function for any purpose other than
883 // a redeclaration (such that we'll be building an expression with the
884 // result), perform template argument deduction and place the
885 // specialization into the result set. We do this to avoid forcing all
886 // callers to perform special deduction for conversion functions.
887 TemplateDeductionInfo Info(R.getNameLoc());
888 FunctionDecl *Specialization = nullptr;
890 const FunctionProtoType *ConvProto
891 = ConvTemplate->getTemplatedDecl()->getType()->getAs<FunctionProtoType>();
892 assert(ConvProto && "Nonsensical conversion function template type");
894 // Compute the type of the function that we would expect the conversion
895 // function to have, if it were to match the name given.
896 // FIXME: Calling convention!
897 FunctionProtoType::ExtProtoInfo EPI = ConvProto->getExtProtoInfo();
898 EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC_C);
899 EPI.ExceptionSpec = EST_None;
900 QualType ExpectedType
901 = R.getSema().Context.getFunctionType(R.getLookupName().getCXXNameType(),
904 // Perform template argument deduction against the type that we would
905 // expect the function to have.
906 if (R.getSema().DeduceTemplateArguments(ConvTemplate, nullptr, ExpectedType,
907 Specialization, Info)
908 == Sema::TDK_Success) {
909 R.addDecl(Specialization);
917 // Performs C++ unqualified lookup into the given file context.
919 CppNamespaceLookup(Sema &S, LookupResult &R, ASTContext &Context,
920 DeclContext *NS, UnqualUsingDirectiveSet &UDirs) {
922 assert(NS && NS->isFileContext() && "CppNamespaceLookup() requires namespace!");
924 // Perform direct name lookup into the LookupCtx.
925 bool Found = LookupDirect(S, R, NS);
927 // Perform direct name lookup into the namespaces nominated by the
928 // using directives whose common ancestor is this namespace.
929 for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(NS))
930 if (LookupDirect(S, R, UUE.getNominatedNamespace()))
938 static bool isNamespaceOrTranslationUnitScope(Scope *S) {
939 if (DeclContext *Ctx = S->getEntity())
940 return Ctx->isFileContext();
944 // Find the next outer declaration context from this scope. This
945 // routine actually returns the semantic outer context, which may
946 // differ from the lexical context (encoded directly in the Scope
947 // stack) when we are parsing a member of a class template. In this
948 // case, the second element of the pair will be true, to indicate that
949 // name lookup should continue searching in this semantic context when
950 // it leaves the current template parameter scope.
951 static std::pair<DeclContext *, bool> findOuterContext(Scope *S) {
952 DeclContext *DC = S->getEntity();
953 DeclContext *Lexical = nullptr;
954 for (Scope *OuterS = S->getParent(); OuterS;
955 OuterS = OuterS->getParent()) {
956 if (OuterS->getEntity()) {
957 Lexical = OuterS->getEntity();
962 // C++ [temp.local]p8:
963 // In the definition of a member of a class template that appears
964 // outside of the namespace containing the class template
965 // definition, the name of a template-parameter hides the name of
966 // a member of this namespace.
973 // template<class T> class B {
978 // template<class C> void N::B<C>::f(C) {
979 // C b; // C is the template parameter, not N::C
982 // In this example, the lexical context we return is the
983 // TranslationUnit, while the semantic context is the namespace N.
984 if (!Lexical || !DC || !S->getParent() ||
985 !S->getParent()->isTemplateParamScope())
986 return std::make_pair(Lexical, false);
988 // Find the outermost template parameter scope.
989 // For the example, this is the scope for the template parameters of
990 // template<class C>.
991 Scope *OutermostTemplateScope = S->getParent();
992 while (OutermostTemplateScope->getParent() &&
993 OutermostTemplateScope->getParent()->isTemplateParamScope())
994 OutermostTemplateScope = OutermostTemplateScope->getParent();
996 // Find the namespace context in which the original scope occurs. In
997 // the example, this is namespace N.
998 DeclContext *Semantic = DC;
999 while (!Semantic->isFileContext())
1000 Semantic = Semantic->getParent();
1002 // Find the declaration context just outside of the template
1003 // parameter scope. This is the context in which the template is
1004 // being lexically declaration (a namespace context). In the
1005 // example, this is the global scope.
1006 if (Lexical->isFileContext() && !Lexical->Equals(Semantic) &&
1007 Lexical->Encloses(Semantic))
1008 return std::make_pair(Semantic, true);
1010 return std::make_pair(Lexical, false);
1014 /// An RAII object to specify that we want to find block scope extern
1016 struct FindLocalExternScope {
1017 FindLocalExternScope(LookupResult &R)
1018 : R(R), OldFindLocalExtern(R.getIdentifierNamespace() &
1019 Decl::IDNS_LocalExtern) {
1020 R.setFindLocalExtern(R.getIdentifierNamespace() & Decl::IDNS_Ordinary);
1023 R.setFindLocalExtern(OldFindLocalExtern);
1025 ~FindLocalExternScope() {
1029 bool OldFindLocalExtern;
1031 } // end anonymous namespace
1033 bool Sema::CppLookupName(LookupResult &R, Scope *S) {
1034 assert(getLangOpts().CPlusPlus && "Can perform only C++ lookup");
1036 DeclarationName Name = R.getLookupName();
1037 Sema::LookupNameKind NameKind = R.getLookupKind();
1039 // If this is the name of an implicitly-declared special member function,
1040 // go through the scope stack to implicitly declare
1041 if (isImplicitlyDeclaredMemberFunctionName(Name)) {
1042 for (Scope *PreS = S; PreS; PreS = PreS->getParent())
1043 if (DeclContext *DC = PreS->getEntity())
1044 DeclareImplicitMemberFunctionsWithName(*this, Name, DC);
1047 // Implicitly declare member functions with the name we're looking for, if in
1048 // fact we are in a scope where it matters.
1051 IdentifierResolver::iterator
1052 I = IdResolver.begin(Name),
1053 IEnd = IdResolver.end();
1055 // First we lookup local scope.
1056 // We don't consider using-directives, as per 7.3.4.p1 [namespace.udir]
1057 // ...During unqualified name lookup (3.4.1), the names appear as if
1058 // they were declared in the nearest enclosing namespace which contains
1059 // both the using-directive and the nominated namespace.
1060 // [Note: in this context, "contains" means "contains directly or
1064 // namespace A { int i; }
1068 // using namespace A;
1069 // ++i; // finds local 'i', A::i appears at global scope
1073 UnqualUsingDirectiveSet UDirs;
1074 bool VisitedUsingDirectives = false;
1075 bool LeftStartingScope = false;
1076 DeclContext *OutsideOfTemplateParamDC = nullptr;
1078 // When performing a scope lookup, we want to find local extern decls.
1079 FindLocalExternScope FindLocals(R);
1081 for (; S && !isNamespaceOrTranslationUnitScope(S); S = S->getParent()) {
1082 DeclContext *Ctx = S->getEntity();
1083 bool SearchNamespaceScope = true;
1084 // Check whether the IdResolver has anything in this scope.
1085 for (; I != IEnd && S->isDeclScope(*I); ++I) {
1086 if (NamedDecl *ND = R.getAcceptableDecl(*I)) {
1087 if (NameKind == LookupRedeclarationWithLinkage &&
1088 !(*I)->isTemplateParameter()) {
1089 // If it's a template parameter, we still find it, so we can diagnose
1090 // the invalid redeclaration.
1092 // Determine whether this (or a previous) declaration is
1094 if (!LeftStartingScope && !Initial->isDeclScope(*I))
1095 LeftStartingScope = true;
1097 // If we found something outside of our starting scope that
1098 // does not have linkage, skip it.
1099 if (LeftStartingScope && !((*I)->hasLinkage())) {
1104 // We found something in this scope, we should not look at the
1106 SearchNamespaceScope = false;
1111 if (!SearchNamespaceScope) {
1113 if (S->isClassScope())
1114 if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(Ctx))
1115 R.setNamingClass(Record);
1119 if (NameKind == LookupLocalFriendName && !S->isClassScope()) {
1120 // C++11 [class.friend]p11:
1121 // If a friend declaration appears in a local class and the name
1122 // specified is an unqualified name, a prior declaration is
1123 // looked up without considering scopes that are outside the
1124 // innermost enclosing non-class scope.
1128 if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
1129 S->getParent() && !S->getParent()->isTemplateParamScope()) {
1130 // We've just searched the last template parameter scope and
1131 // found nothing, so look into the contexts between the
1132 // lexical and semantic declaration contexts returned by
1133 // findOuterContext(). This implements the name lookup behavior
1134 // of C++ [temp.local]p8.
1135 Ctx = OutsideOfTemplateParamDC;
1136 OutsideOfTemplateParamDC = nullptr;
1140 DeclContext *OuterCtx;
1141 bool SearchAfterTemplateScope;
1142 std::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
1143 if (SearchAfterTemplateScope)
1144 OutsideOfTemplateParamDC = OuterCtx;
1146 for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
1147 // We do not directly look into transparent contexts, since
1148 // those entities will be found in the nearest enclosing
1149 // non-transparent context.
1150 if (Ctx->isTransparentContext())
1153 // We do not look directly into function or method contexts,
1154 // since all of the local variables and parameters of the
1155 // function/method are present within the Scope.
1156 if (Ctx->isFunctionOrMethod()) {
1157 // If we have an Objective-C instance method, look for ivars
1158 // in the corresponding interface.
1159 if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
1160 if (Method->isInstanceMethod() && Name.getAsIdentifierInfo())
1161 if (ObjCInterfaceDecl *Class = Method->getClassInterface()) {
1162 ObjCInterfaceDecl *ClassDeclared;
1163 if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(
1164 Name.getAsIdentifierInfo(),
1166 if (NamedDecl *ND = R.getAcceptableDecl(Ivar)) {
1178 // If this is a file context, we need to perform unqualified name
1179 // lookup considering using directives.
1180 if (Ctx->isFileContext()) {
1181 // If we haven't handled using directives yet, do so now.
1182 if (!VisitedUsingDirectives) {
1183 // Add using directives from this context up to the top level.
1184 for (DeclContext *UCtx = Ctx; UCtx; UCtx = UCtx->getParent()) {
1185 if (UCtx->isTransparentContext())
1188 UDirs.visit(UCtx, UCtx);
1191 // Find the innermost file scope, so we can add using directives
1192 // from local scopes.
1193 Scope *InnermostFileScope = S;
1194 while (InnermostFileScope &&
1195 !isNamespaceOrTranslationUnitScope(InnermostFileScope))
1196 InnermostFileScope = InnermostFileScope->getParent();
1197 UDirs.visitScopeChain(Initial, InnermostFileScope);
1201 VisitedUsingDirectives = true;
1204 if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs)) {
1212 // Perform qualified name lookup into this context.
1213 // FIXME: In some cases, we know that every name that could be found by
1214 // this qualified name lookup will also be on the identifier chain. For
1215 // example, inside a class without any base classes, we never need to
1216 // perform qualified lookup because all of the members are on top of the
1217 // identifier chain.
1218 if (LookupQualifiedName(R, Ctx, /*InUnqualifiedLookup=*/true))
1224 // Stop if we ran out of scopes.
1225 // FIXME: This really, really shouldn't be happening.
1226 if (!S) return false;
1228 // If we are looking for members, no need to look into global/namespace scope.
1229 if (NameKind == LookupMemberName)
1232 // Collect UsingDirectiveDecls in all scopes, and recursively all
1233 // nominated namespaces by those using-directives.
1235 // FIXME: Cache this sorted list in Scope structure, and DeclContext, so we
1236 // don't build it for each lookup!
1237 if (!VisitedUsingDirectives) {
1238 UDirs.visitScopeChain(Initial, S);
1242 // If we're not performing redeclaration lookup, do not look for local
1243 // extern declarations outside of a function scope.
1244 if (!R.isForRedeclaration())
1245 FindLocals.restore();
1247 // Lookup namespace scope, and global scope.
1248 // Unqualified name lookup in C++ requires looking into scopes
1249 // that aren't strictly lexical, and therefore we walk through the
1250 // context as well as walking through the scopes.
1251 for (; S; S = S->getParent()) {
1252 // Check whether the IdResolver has anything in this scope.
1254 for (; I != IEnd && S->isDeclScope(*I); ++I) {
1255 if (NamedDecl *ND = R.getAcceptableDecl(*I)) {
1256 // We found something. Look for anything else in our scope
1257 // with this same name and in an acceptable identifier
1258 // namespace, so that we can construct an overload set if we
1265 if (Found && S->isTemplateParamScope()) {
1270 DeclContext *Ctx = S->getEntity();
1271 if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
1272 S->getParent() && !S->getParent()->isTemplateParamScope()) {
1273 // We've just searched the last template parameter scope and
1274 // found nothing, so look into the contexts between the
1275 // lexical and semantic declaration contexts returned by
1276 // findOuterContext(). This implements the name lookup behavior
1277 // of C++ [temp.local]p8.
1278 Ctx = OutsideOfTemplateParamDC;
1279 OutsideOfTemplateParamDC = nullptr;
1283 DeclContext *OuterCtx;
1284 bool SearchAfterTemplateScope;
1285 std::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
1286 if (SearchAfterTemplateScope)
1287 OutsideOfTemplateParamDC = OuterCtx;
1289 for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
1290 // We do not directly look into transparent contexts, since
1291 // those entities will be found in the nearest enclosing
1292 // non-transparent context.
1293 if (Ctx->isTransparentContext())
1296 // If we have a context, and it's not a context stashed in the
1297 // template parameter scope for an out-of-line definition, also
1298 // look into that context.
1299 if (!(Found && S->isTemplateParamScope())) {
1300 assert(Ctx->isFileContext() &&
1301 "We should have been looking only at file context here already.");
1303 // Look into context considering using-directives.
1304 if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs))
1313 if (R.isForRedeclaration() && !Ctx->isTransparentContext())
1318 if (R.isForRedeclaration() && Ctx && !Ctx->isTransparentContext())
1325 /// \brief Find the declaration that a class temploid member specialization was
1326 /// instantiated from, or the member itself if it is an explicit specialization.
1327 static Decl *getInstantiatedFrom(Decl *D, MemberSpecializationInfo *MSInfo) {
1328 return MSInfo->isExplicitSpecialization() ? D : MSInfo->getInstantiatedFrom();
1331 Module *Sema::getOwningModule(Decl *Entity) {
1332 // If it's imported, grab its owning module.
1333 Module *M = Entity->getImportedOwningModule();
1334 if (M || !isa<NamedDecl>(Entity) || !cast<NamedDecl>(Entity)->isHidden())
1336 assert(!Entity->isFromASTFile() &&
1337 "hidden entity from AST file has no owning module");
1339 if (!getLangOpts().ModulesLocalVisibility) {
1340 // If we're not tracking visibility locally, the only way a declaration
1341 // can be hidden and local is if it's hidden because it's parent is (for
1342 // instance, maybe this is a lazily-declared special member of an imported
1344 auto *Parent = cast<NamedDecl>(Entity->getDeclContext());
1345 assert(Parent->isHidden() && "unexpectedly hidden decl");
1346 return getOwningModule(Parent);
1349 // It's local and hidden; grab or compute its owning module.
1350 M = Entity->getLocalOwningModule();
1354 if (auto *Containing =
1355 PP.getModuleContainingLocation(Entity->getLocation())) {
1357 } else if (Entity->isInvalidDecl() || Entity->getLocation().isInvalid()) {
1358 // Don't bother tracking visibility for invalid declarations with broken
1360 cast<NamedDecl>(Entity)->setHidden(false);
1362 // We need to assign a module to an entity that exists outside of any
1363 // module, so that we can hide it from modules that we textually enter.
1364 // Invent a fake module for all such entities.
1365 if (!CachedFakeTopLevelModule) {
1366 CachedFakeTopLevelModule =
1367 PP.getHeaderSearchInfo().getModuleMap().findOrCreateModule(
1368 "<top-level>", nullptr, false, false).first;
1370 auto &SrcMgr = PP.getSourceManager();
1371 SourceLocation StartLoc =
1372 SrcMgr.getLocForStartOfFile(SrcMgr.getMainFileID());
1373 auto &TopLevel = ModuleScopes.empty()
1375 : ModuleScopes[0].OuterVisibleModules;
1376 TopLevel.setVisible(CachedFakeTopLevelModule, StartLoc);
1379 M = CachedFakeTopLevelModule;
1383 Entity->setLocalOwningModule(M);
1387 void Sema::makeMergedDefinitionVisible(NamedDecl *ND, SourceLocation Loc) {
1388 if (auto *M = PP.getModuleContainingLocation(Loc))
1389 Context.mergeDefinitionIntoModule(ND, M);
1391 // We're not building a module; just make the definition visible.
1392 ND->setHidden(false);
1394 // If ND is a template declaration, make the template parameters
1395 // visible too. They're not (necessarily) within a mergeable DeclContext.
1396 if (auto *TD = dyn_cast<TemplateDecl>(ND))
1397 for (auto *Param : *TD->getTemplateParameters())
1398 makeMergedDefinitionVisible(Param, Loc);
1401 /// \brief Find the module in which the given declaration was defined.
1402 static Module *getDefiningModule(Sema &S, Decl *Entity) {
1403 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Entity)) {
1404 // If this function was instantiated from a template, the defining module is
1405 // the module containing the pattern.
1406 if (FunctionDecl *Pattern = FD->getTemplateInstantiationPattern())
1408 } else if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Entity)) {
1409 if (CXXRecordDecl *Pattern = RD->getTemplateInstantiationPattern())
1411 } else if (EnumDecl *ED = dyn_cast<EnumDecl>(Entity)) {
1412 if (MemberSpecializationInfo *MSInfo = ED->getMemberSpecializationInfo())
1413 Entity = getInstantiatedFrom(ED, MSInfo);
1414 } else if (VarDecl *VD = dyn_cast<VarDecl>(Entity)) {
1415 // FIXME: Map from variable template specializations back to the template.
1416 if (MemberSpecializationInfo *MSInfo = VD->getMemberSpecializationInfo())
1417 Entity = getInstantiatedFrom(VD, MSInfo);
1420 // Walk up to the containing context. That might also have been instantiated
1422 DeclContext *Context = Entity->getDeclContext();
1423 if (Context->isFileContext())
1424 return S.getOwningModule(Entity);
1425 return getDefiningModule(S, cast<Decl>(Context));
1428 llvm::DenseSet<Module*> &Sema::getLookupModules() {
1429 unsigned N = ActiveTemplateInstantiations.size();
1430 for (unsigned I = ActiveTemplateInstantiationLookupModules.size();
1433 getDefiningModule(*this, ActiveTemplateInstantiations[I].Entity);
1434 if (M && !LookupModulesCache.insert(M).second)
1436 ActiveTemplateInstantiationLookupModules.push_back(M);
1438 return LookupModulesCache;
1441 bool Sema::hasVisibleMergedDefinition(NamedDecl *Def) {
1442 for (Module *Merged : Context.getModulesWithMergedDefinition(Def))
1443 if (isModuleVisible(Merged))
1448 template<typename ParmDecl>
1450 hasVisibleDefaultArgument(Sema &S, const ParmDecl *D,
1451 llvm::SmallVectorImpl<Module *> *Modules) {
1452 if (!D->hasDefaultArgument())
1456 auto &DefaultArg = D->getDefaultArgStorage();
1457 if (!DefaultArg.isInherited() && S.isVisible(D))
1460 if (!DefaultArg.isInherited() && Modules) {
1461 auto *NonConstD = const_cast<ParmDecl*>(D);
1462 Modules->push_back(S.getOwningModule(NonConstD));
1463 const auto &Merged = S.Context.getModulesWithMergedDefinition(NonConstD);
1464 Modules->insert(Modules->end(), Merged.begin(), Merged.end());
1467 // If there was a previous default argument, maybe its parameter is visible.
1468 D = DefaultArg.getInheritedFrom();
1473 bool Sema::hasVisibleDefaultArgument(const NamedDecl *D,
1474 llvm::SmallVectorImpl<Module *> *Modules) {
1475 if (auto *P = dyn_cast<TemplateTypeParmDecl>(D))
1476 return ::hasVisibleDefaultArgument(*this, P, Modules);
1477 if (auto *P = dyn_cast<NonTypeTemplateParmDecl>(D))
1478 return ::hasVisibleDefaultArgument(*this, P, Modules);
1479 return ::hasVisibleDefaultArgument(*this, cast<TemplateTemplateParmDecl>(D),
1483 bool Sema::hasVisibleMemberSpecialization(
1484 const NamedDecl *D, llvm::SmallVectorImpl<Module *> *Modules) {
1485 assert(isa<CXXRecordDecl>(D->getDeclContext()) &&
1486 "not a member specialization");
1487 for (auto *Redecl : D->redecls()) {
1488 // If the specialization is declared at namespace scope, then it's a member
1489 // specialization declaration. If it's lexically inside the class
1490 // definition then it was instantiated.
1492 // FIXME: This is a hack. There should be a better way to determine this.
1493 // FIXME: What about MS-style explicit specializations declared within a
1494 // class definition?
1495 if (Redecl->getLexicalDeclContext()->isFileContext()) {
1496 auto *NonConstR = const_cast<NamedDecl*>(cast<NamedDecl>(Redecl));
1498 if (isVisible(NonConstR))
1502 Modules->push_back(getOwningModule(NonConstR));
1503 const auto &Merged = Context.getModulesWithMergedDefinition(NonConstR);
1504 Modules->insert(Modules->end(), Merged.begin(), Merged.end());
1512 /// \brief Determine whether a declaration is visible to name lookup.
1514 /// This routine determines whether the declaration D is visible in the current
1515 /// lookup context, taking into account the current template instantiation
1516 /// stack. During template instantiation, a declaration is visible if it is
1517 /// visible from a module containing any entity on the template instantiation
1518 /// path (by instantiating a template, you allow it to see the declarations that
1519 /// your module can see, including those later on in your module).
1520 bool LookupResult::isVisibleSlow(Sema &SemaRef, NamedDecl *D) {
1521 assert(D->isHidden() && "should not call this: not in slow case");
1522 Module *DeclModule = nullptr;
1524 if (SemaRef.getLangOpts().ModulesLocalVisibility) {
1525 DeclModule = SemaRef.getOwningModule(D);
1527 // getOwningModule() may have decided the declaration should not be hidden.
1528 assert(!D->isHidden() && "hidden decl not from a module");
1532 // If the owning module is visible, and the decl is not module private,
1533 // then the decl is visible too. (Module private is ignored within the same
1534 // top-level module.)
1535 if ((!D->isFromASTFile() || !D->isModulePrivate()) &&
1536 (SemaRef.isModuleVisible(DeclModule) ||
1537 SemaRef.hasVisibleMergedDefinition(D)))
1541 // If this declaration is not at namespace scope nor module-private,
1542 // then it is visible if its lexical parent has a visible definition.
1543 DeclContext *DC = D->getLexicalDeclContext();
1544 if (!D->isModulePrivate() && DC && !DC->isFileContext() &&
1545 !isa<LinkageSpecDecl>(DC) && !isa<ExportDecl>(DC)) {
1546 // For a parameter, check whether our current template declaration's
1547 // lexical context is visible, not whether there's some other visible
1548 // definition of it, because parameters aren't "within" the definition.
1550 // In C++ we need to check for a visible definition due to ODR merging,
1551 // and in C we must not because each declaration of a function gets its own
1552 // set of declarations for tags in prototype scope.
1553 if ((D->isTemplateParameter() || isa<ParmVarDecl>(D)
1554 || (isa<FunctionDecl>(DC) && !SemaRef.getLangOpts().CPlusPlus))
1555 ? isVisible(SemaRef, cast<NamedDecl>(DC))
1556 : SemaRef.hasVisibleDefinition(cast<NamedDecl>(DC))) {
1557 if (SemaRef.ActiveTemplateInstantiations.empty() &&
1558 // FIXME: Do something better in this case.
1559 !SemaRef.getLangOpts().ModulesLocalVisibility) {
1560 // Cache the fact that this declaration is implicitly visible because
1561 // its parent has a visible definition.
1562 D->setHidden(false);
1569 // Find the extra places where we need to look.
1570 llvm::DenseSet<Module*> &LookupModules = SemaRef.getLookupModules();
1571 if (LookupModules.empty())
1575 DeclModule = SemaRef.getOwningModule(D);
1576 assert(DeclModule && "hidden decl not from a module");
1579 // If our lookup set contains the decl's module, it's visible.
1580 if (LookupModules.count(DeclModule))
1583 // If the declaration isn't exported, it's not visible in any other module.
1584 if (D->isModulePrivate())
1587 // Check whether DeclModule is transitively exported to an import of
1589 return std::any_of(LookupModules.begin(), LookupModules.end(),
1590 [&](Module *M) { return M->isModuleVisible(DeclModule); });
1593 bool Sema::isVisibleSlow(const NamedDecl *D) {
1594 return LookupResult::isVisible(*this, const_cast<NamedDecl*>(D));
1597 bool Sema::shouldLinkPossiblyHiddenDecl(LookupResult &R, const NamedDecl *New) {
1602 return New->isExternallyVisible();
1605 /// \brief Retrieve the visible declaration corresponding to D, if any.
1607 /// This routine determines whether the declaration D is visible in the current
1608 /// module, with the current imports. If not, it checks whether any
1609 /// redeclaration of D is visible, and if so, returns that declaration.
1611 /// \returns D, or a visible previous declaration of D, whichever is more recent
1612 /// and visible. If no declaration of D is visible, returns null.
1613 static NamedDecl *findAcceptableDecl(Sema &SemaRef, NamedDecl *D) {
1614 assert(!LookupResult::isVisible(SemaRef, D) && "not in slow case");
1616 for (auto RD : D->redecls()) {
1617 // Don't bother with extra checks if we already know this one isn't visible.
1621 auto ND = cast<NamedDecl>(RD);
1622 // FIXME: This is wrong in the case where the previous declaration is not
1623 // visible in the same scope as D. This needs to be done much more
1625 if (LookupResult::isVisible(SemaRef, ND))
1632 bool Sema::hasVisibleDeclarationSlow(const NamedDecl *D,
1633 llvm::SmallVectorImpl<Module *> *Modules) {
1634 assert(!isVisible(D) && "not in slow case");
1636 for (auto *Redecl : D->redecls()) {
1637 auto *NonConstR = const_cast<NamedDecl*>(cast<NamedDecl>(Redecl));
1638 if (isVisible(NonConstR))
1642 Modules->push_back(getOwningModule(NonConstR));
1643 const auto &Merged = Context.getModulesWithMergedDefinition(NonConstR);
1644 Modules->insert(Modules->end(), Merged.begin(), Merged.end());
1651 NamedDecl *LookupResult::getAcceptableDeclSlow(NamedDecl *D) const {
1652 if (auto *ND = dyn_cast<NamespaceDecl>(D)) {
1653 // Namespaces are a bit of a special case: we expect there to be a lot of
1654 // redeclarations of some namespaces, all declarations of a namespace are
1655 // essentially interchangeable, all declarations are found by name lookup
1656 // if any is, and namespaces are never looked up during template
1657 // instantiation. So we benefit from caching the check in this case, and
1658 // it is correct to do so.
1659 auto *Key = ND->getCanonicalDecl();
1660 if (auto *Acceptable = getSema().VisibleNamespaceCache.lookup(Key))
1663 isVisible(getSema(), Key) ? Key : findAcceptableDecl(getSema(), Key);
1665 getSema().VisibleNamespaceCache.insert(std::make_pair(Key, Acceptable));
1669 return findAcceptableDecl(getSema(), D);
1672 /// @brief Perform unqualified name lookup starting from a given
1675 /// Unqualified name lookup (C++ [basic.lookup.unqual], C99 6.2.1) is
1676 /// used to find names within the current scope. For example, 'x' in
1680 /// return x; // unqualified name look finds 'x' in the global scope
1684 /// Different lookup criteria can find different names. For example, a
1685 /// particular scope can have both a struct and a function of the same
1686 /// name, and each can be found by certain lookup criteria. For more
1687 /// information about lookup criteria, see the documentation for the
1688 /// class LookupCriteria.
1690 /// @param S The scope from which unqualified name lookup will
1691 /// begin. If the lookup criteria permits, name lookup may also search
1692 /// in the parent scopes.
1694 /// @param [in,out] R Specifies the lookup to perform (e.g., the name to
1695 /// look up and the lookup kind), and is updated with the results of lookup
1696 /// including zero or more declarations and possibly additional information
1697 /// used to diagnose ambiguities.
1699 /// @returns \c true if lookup succeeded and false otherwise.
1700 bool Sema::LookupName(LookupResult &R, Scope *S, bool AllowBuiltinCreation) {
1701 DeclarationName Name = R.getLookupName();
1702 if (!Name) return false;
1704 LookupNameKind NameKind = R.getLookupKind();
1706 if (!getLangOpts().CPlusPlus) {
1707 // Unqualified name lookup in C/Objective-C is purely lexical, so
1708 // search in the declarations attached to the name.
1709 if (NameKind == Sema::LookupRedeclarationWithLinkage) {
1710 // Find the nearest non-transparent declaration scope.
1711 while (!(S->getFlags() & Scope::DeclScope) ||
1712 (S->getEntity() && S->getEntity()->isTransparentContext()))
1716 // When performing a scope lookup, we want to find local extern decls.
1717 FindLocalExternScope FindLocals(R);
1719 // Scan up the scope chain looking for a decl that matches this
1720 // identifier that is in the appropriate namespace. This search
1721 // should not take long, as shadowing of names is uncommon, and
1722 // deep shadowing is extremely uncommon.
1723 bool LeftStartingScope = false;
1725 for (IdentifierResolver::iterator I = IdResolver.begin(Name),
1726 IEnd = IdResolver.end();
1728 if (NamedDecl *D = R.getAcceptableDecl(*I)) {
1729 if (NameKind == LookupRedeclarationWithLinkage) {
1730 // Determine whether this (or a previous) declaration is
1732 if (!LeftStartingScope && !S->isDeclScope(*I))
1733 LeftStartingScope = true;
1735 // If we found something outside of our starting scope that
1736 // does not have linkage, skip it.
1737 if (LeftStartingScope && !((*I)->hasLinkage())) {
1742 else if (NameKind == LookupObjCImplicitSelfParam &&
1743 !isa<ImplicitParamDecl>(*I))
1748 // Check whether there are any other declarations with the same name
1749 // and in the same scope.
1751 // Find the scope in which this declaration was declared (if it
1752 // actually exists in a Scope).
1753 while (S && !S->isDeclScope(D))
1756 // If the scope containing the declaration is the translation unit,
1757 // then we'll need to perform our checks based on the matching
1758 // DeclContexts rather than matching scopes.
1759 if (S && isNamespaceOrTranslationUnitScope(S))
1762 // Compute the DeclContext, if we need it.
1763 DeclContext *DC = nullptr;
1765 DC = (*I)->getDeclContext()->getRedeclContext();
1767 IdentifierResolver::iterator LastI = I;
1768 for (++LastI; LastI != IEnd; ++LastI) {
1770 // Match based on scope.
1771 if (!S->isDeclScope(*LastI))
1774 // Match based on DeclContext.
1776 = (*LastI)->getDeclContext()->getRedeclContext();
1777 if (!LastDC->Equals(DC))
1781 // If the declaration is in the right namespace and visible, add it.
1782 if (NamedDecl *LastD = R.getAcceptableDecl(*LastI))
1792 // Perform C++ unqualified name lookup.
1793 if (CppLookupName(R, S))
1797 // If we didn't find a use of this identifier, and if the identifier
1798 // corresponds to a compiler builtin, create the decl object for the builtin
1799 // now, injecting it into translation unit scope, and return it.
1800 if (AllowBuiltinCreation && LookupBuiltin(*this, R))
1803 // If we didn't find a use of this identifier, the ExternalSource
1804 // may be able to handle the situation.
1805 // Note: some lookup failures are expected!
1806 // See e.g. R.isForRedeclaration().
1807 return (ExternalSource && ExternalSource->LookupUnqualified(R, S));
1810 /// @brief Perform qualified name lookup in the namespaces nominated by
1811 /// using directives by the given context.
1813 /// C++98 [namespace.qual]p2:
1814 /// Given X::m (where X is a user-declared namespace), or given \::m
1815 /// (where X is the global namespace), let S be the set of all
1816 /// declarations of m in X and in the transitive closure of all
1817 /// namespaces nominated by using-directives in X and its used
1818 /// namespaces, except that using-directives are ignored in any
1819 /// namespace, including X, directly containing one or more
1820 /// declarations of m. No namespace is searched more than once in
1821 /// the lookup of a name. If S is the empty set, the program is
1822 /// ill-formed. Otherwise, if S has exactly one member, or if the
1823 /// context of the reference is a using-declaration
1824 /// (namespace.udecl), S is the required set of declarations of
1825 /// m. Otherwise if the use of m is not one that allows a unique
1826 /// declaration to be chosen from S, the program is ill-formed.
1828 /// C++98 [namespace.qual]p5:
1829 /// During the lookup of a qualified namespace member name, if the
1830 /// lookup finds more than one declaration of the member, and if one
1831 /// declaration introduces a class name or enumeration name and the
1832 /// other declarations either introduce the same object, the same
1833 /// enumerator or a set of functions, the non-type name hides the
1834 /// class or enumeration name if and only if the declarations are
1835 /// from the same namespace; otherwise (the declarations are from
1836 /// different namespaces), the program is ill-formed.
1837 static bool LookupQualifiedNameInUsingDirectives(Sema &S, LookupResult &R,
1838 DeclContext *StartDC) {
1839 assert(StartDC->isFileContext() && "start context is not a file context");
1841 DeclContext::udir_range UsingDirectives = StartDC->using_directives();
1842 if (UsingDirectives.begin() == UsingDirectives.end()) return false;
1844 // We have at least added all these contexts to the queue.
1845 llvm::SmallPtrSet<DeclContext*, 8> Visited;
1846 Visited.insert(StartDC);
1848 // We have not yet looked into these namespaces, much less added
1849 // their "using-children" to the queue.
1850 SmallVector<NamespaceDecl*, 8> Queue;
1852 // We have already looked into the initial namespace; seed the queue
1853 // with its using-children.
1854 for (auto *I : UsingDirectives) {
1855 NamespaceDecl *ND = I->getNominatedNamespace()->getOriginalNamespace();
1856 if (Visited.insert(ND).second)
1857 Queue.push_back(ND);
1860 // The easiest way to implement the restriction in [namespace.qual]p5
1861 // is to check whether any of the individual results found a tag
1862 // and, if so, to declare an ambiguity if the final result is not
1864 bool FoundTag = false;
1865 bool FoundNonTag = false;
1867 LookupResult LocalR(LookupResult::Temporary, R);
1870 while (!Queue.empty()) {
1871 NamespaceDecl *ND = Queue.pop_back_val();
1873 // We go through some convolutions here to avoid copying results
1874 // between LookupResults.
1875 bool UseLocal = !R.empty();
1876 LookupResult &DirectR = UseLocal ? LocalR : R;
1877 bool FoundDirect = LookupDirect(S, DirectR, ND);
1880 // First do any local hiding.
1881 DirectR.resolveKind();
1883 // If the local result is a tag, remember that.
1884 if (DirectR.isSingleTagDecl())
1889 // Append the local results to the total results if necessary.
1891 R.addAllDecls(LocalR);
1896 // If we find names in this namespace, ignore its using directives.
1902 for (auto I : ND->using_directives()) {
1903 NamespaceDecl *Nom = I->getNominatedNamespace();
1904 if (Visited.insert(Nom).second)
1905 Queue.push_back(Nom);
1910 if (FoundTag && FoundNonTag)
1911 R.setAmbiguousQualifiedTagHiding();
1919 /// \brief Callback that looks for any member of a class with the given name.
1920 static bool LookupAnyMember(const CXXBaseSpecifier *Specifier,
1921 CXXBasePath &Path, DeclarationName Name) {
1922 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl();
1924 Path.Decls = BaseRecord->lookup(Name);
1925 return !Path.Decls.empty();
1928 /// \brief Determine whether the given set of member declarations contains only
1929 /// static members, nested types, and enumerators.
1930 template<typename InputIterator>
1931 static bool HasOnlyStaticMembers(InputIterator First, InputIterator Last) {
1932 Decl *D = (*First)->getUnderlyingDecl();
1933 if (isa<VarDecl>(D) || isa<TypeDecl>(D) || isa<EnumConstantDecl>(D))
1936 if (isa<CXXMethodDecl>(D)) {
1937 // Determine whether all of the methods are static.
1938 bool AllMethodsAreStatic = true;
1939 for(; First != Last; ++First) {
1940 D = (*First)->getUnderlyingDecl();
1942 if (!isa<CXXMethodDecl>(D)) {
1943 assert(isa<TagDecl>(D) && "Non-function must be a tag decl");
1947 if (!cast<CXXMethodDecl>(D)->isStatic()) {
1948 AllMethodsAreStatic = false;
1953 if (AllMethodsAreStatic)
1960 /// \brief Perform qualified name lookup into a given context.
1962 /// Qualified name lookup (C++ [basic.lookup.qual]) is used to find
1963 /// names when the context of those names is explicit specified, e.g.,
1964 /// "std::vector" or "x->member", or as part of unqualified name lookup.
1966 /// Different lookup criteria can find different names. For example, a
1967 /// particular scope can have both a struct and a function of the same
1968 /// name, and each can be found by certain lookup criteria. For more
1969 /// information about lookup criteria, see the documentation for the
1970 /// class LookupCriteria.
1972 /// \param R captures both the lookup criteria and any lookup results found.
1974 /// \param LookupCtx The context in which qualified name lookup will
1975 /// search. If the lookup criteria permits, name lookup may also search
1976 /// in the parent contexts or (for C++ classes) base classes.
1978 /// \param InUnqualifiedLookup true if this is qualified name lookup that
1979 /// occurs as part of unqualified name lookup.
1981 /// \returns true if lookup succeeded, false if it failed.
1982 bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
1983 bool InUnqualifiedLookup) {
1984 assert(LookupCtx && "Sema::LookupQualifiedName requires a lookup context");
1986 if (!R.getLookupName())
1989 // Make sure that the declaration context is complete.
1990 assert((!isa<TagDecl>(LookupCtx) ||
1991 LookupCtx->isDependentContext() ||
1992 cast<TagDecl>(LookupCtx)->isCompleteDefinition() ||
1993 cast<TagDecl>(LookupCtx)->isBeingDefined()) &&
1994 "Declaration context must already be complete!");
1996 struct QualifiedLookupInScope {
1998 DeclContext *Context;
1999 // Set flag in DeclContext informing debugger that we're looking for qualified name
2000 QualifiedLookupInScope(DeclContext *ctx) : Context(ctx) {
2001 oldVal = ctx->setUseQualifiedLookup();
2003 ~QualifiedLookupInScope() {
2004 Context->setUseQualifiedLookup(oldVal);
2008 if (LookupDirect(*this, R, LookupCtx)) {
2010 if (isa<CXXRecordDecl>(LookupCtx))
2011 R.setNamingClass(cast<CXXRecordDecl>(LookupCtx));
2015 // Don't descend into implied contexts for redeclarations.
2016 // C++98 [namespace.qual]p6:
2017 // In a declaration for a namespace member in which the
2018 // declarator-id is a qualified-id, given that the qualified-id
2019 // for the namespace member has the form
2020 // nested-name-specifier unqualified-id
2021 // the unqualified-id shall name a member of the namespace
2022 // designated by the nested-name-specifier.
2023 // See also [class.mfct]p5 and [class.static.data]p2.
2024 if (R.isForRedeclaration())
2027 // If this is a namespace, look it up in the implied namespaces.
2028 if (LookupCtx->isFileContext())
2029 return LookupQualifiedNameInUsingDirectives(*this, R, LookupCtx);
2031 // If this isn't a C++ class, we aren't allowed to look into base
2032 // classes, we're done.
2033 CXXRecordDecl *LookupRec = dyn_cast<CXXRecordDecl>(LookupCtx);
2034 if (!LookupRec || !LookupRec->getDefinition())
2037 // If we're performing qualified name lookup into a dependent class,
2038 // then we are actually looking into a current instantiation. If we have any
2039 // dependent base classes, then we either have to delay lookup until
2040 // template instantiation time (at which point all bases will be available)
2041 // or we have to fail.
2042 if (!InUnqualifiedLookup && LookupRec->isDependentContext() &&
2043 LookupRec->hasAnyDependentBases()) {
2044 R.setNotFoundInCurrentInstantiation();
2048 // Perform lookup into our base classes.
2050 Paths.setOrigin(LookupRec);
2052 // Look for this member in our base classes
2053 bool (*BaseCallback)(const CXXBaseSpecifier *Specifier, CXXBasePath &Path,
2054 DeclarationName Name) = nullptr;
2055 switch (R.getLookupKind()) {
2056 case LookupObjCImplicitSelfParam:
2057 case LookupOrdinaryName:
2058 case LookupMemberName:
2059 case LookupRedeclarationWithLinkage:
2060 case LookupLocalFriendName:
2061 BaseCallback = &CXXRecordDecl::FindOrdinaryMember;
2065 BaseCallback = &CXXRecordDecl::FindTagMember;
2069 BaseCallback = &LookupAnyMember;
2072 case LookupOMPReductionName:
2073 BaseCallback = &CXXRecordDecl::FindOMPReductionMember;
2076 case LookupUsingDeclName:
2077 // This lookup is for redeclarations only.
2079 case LookupOperatorName:
2080 case LookupNamespaceName:
2081 case LookupObjCProtocolName:
2083 // These lookups will never find a member in a C++ class (or base class).
2086 case LookupNestedNameSpecifierName:
2087 BaseCallback = &CXXRecordDecl::FindNestedNameSpecifierMember;
2091 DeclarationName Name = R.getLookupName();
2092 if (!LookupRec->lookupInBases(
2093 [=](const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
2094 return BaseCallback(Specifier, Path, Name);
2099 R.setNamingClass(LookupRec);
2101 // C++ [class.member.lookup]p2:
2102 // [...] If the resulting set of declarations are not all from
2103 // sub-objects of the same type, or the set has a nonstatic member
2104 // and includes members from distinct sub-objects, there is an
2105 // ambiguity and the program is ill-formed. Otherwise that set is
2106 // the result of the lookup.
2107 QualType SubobjectType;
2108 int SubobjectNumber = 0;
2109 AccessSpecifier SubobjectAccess = AS_none;
2111 for (CXXBasePaths::paths_iterator Path = Paths.begin(), PathEnd = Paths.end();
2112 Path != PathEnd; ++Path) {
2113 const CXXBasePathElement &PathElement = Path->back();
2115 // Pick the best (i.e. most permissive i.e. numerically lowest) access
2116 // across all paths.
2117 SubobjectAccess = std::min(SubobjectAccess, Path->Access);
2119 // Determine whether we're looking at a distinct sub-object or not.
2120 if (SubobjectType.isNull()) {
2121 // This is the first subobject we've looked at. Record its type.
2122 SubobjectType = Context.getCanonicalType(PathElement.Base->getType());
2123 SubobjectNumber = PathElement.SubobjectNumber;
2128 != Context.getCanonicalType(PathElement.Base->getType())) {
2129 // We found members of the given name in two subobjects of
2130 // different types. If the declaration sets aren't the same, this
2131 // lookup is ambiguous.
2132 if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end())) {
2133 CXXBasePaths::paths_iterator FirstPath = Paths.begin();
2134 DeclContext::lookup_iterator FirstD = FirstPath->Decls.begin();
2135 DeclContext::lookup_iterator CurrentD = Path->Decls.begin();
2137 while (FirstD != FirstPath->Decls.end() &&
2138 CurrentD != Path->Decls.end()) {
2139 if ((*FirstD)->getUnderlyingDecl()->getCanonicalDecl() !=
2140 (*CurrentD)->getUnderlyingDecl()->getCanonicalDecl())
2147 if (FirstD == FirstPath->Decls.end() &&
2148 CurrentD == Path->Decls.end())
2152 R.setAmbiguousBaseSubobjectTypes(Paths);
2156 if (SubobjectNumber != PathElement.SubobjectNumber) {
2157 // We have a different subobject of the same type.
2159 // C++ [class.member.lookup]p5:
2160 // A static member, a nested type or an enumerator defined in
2161 // a base class T can unambiguously be found even if an object
2162 // has more than one base class subobject of type T.
2163 if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end()))
2166 // We have found a nonstatic member name in multiple, distinct
2167 // subobjects. Name lookup is ambiguous.
2168 R.setAmbiguousBaseSubobjects(Paths);
2173 // Lookup in a base class succeeded; return these results.
2175 for (auto *D : Paths.front().Decls) {
2176 AccessSpecifier AS = CXXRecordDecl::MergeAccess(SubobjectAccess,
2184 /// \brief Performs qualified name lookup or special type of lookup for
2185 /// "__super::" scope specifier.
2187 /// This routine is a convenience overload meant to be called from contexts
2188 /// that need to perform a qualified name lookup with an optional C++ scope
2189 /// specifier that might require special kind of lookup.
2191 /// \param R captures both the lookup criteria and any lookup results found.
2193 /// \param LookupCtx The context in which qualified name lookup will
2196 /// \param SS An optional C++ scope-specifier.
2198 /// \returns true if lookup succeeded, false if it failed.
2199 bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
2201 auto *NNS = SS.getScopeRep();
2202 if (NNS && NNS->getKind() == NestedNameSpecifier::Super)
2203 return LookupInSuper(R, NNS->getAsRecordDecl());
2206 return LookupQualifiedName(R, LookupCtx);
2209 /// @brief Performs name lookup for a name that was parsed in the
2210 /// source code, and may contain a C++ scope specifier.
2212 /// This routine is a convenience routine meant to be called from
2213 /// contexts that receive a name and an optional C++ scope specifier
2214 /// (e.g., "N::M::x"). It will then perform either qualified or
2215 /// unqualified name lookup (with LookupQualifiedName or LookupName,
2216 /// respectively) on the given name and return those results. It will
2217 /// perform a special type of lookup for "__super::" scope specifier.
2219 /// @param S The scope from which unqualified name lookup will
2222 /// @param SS An optional C++ scope-specifier, e.g., "::N::M".
2224 /// @param EnteringContext Indicates whether we are going to enter the
2225 /// context of the scope-specifier SS (if present).
2227 /// @returns True if any decls were found (but possibly ambiguous)
2228 bool Sema::LookupParsedName(LookupResult &R, Scope *S, CXXScopeSpec *SS,
2229 bool AllowBuiltinCreation, bool EnteringContext) {
2230 if (SS && SS->isInvalid()) {
2231 // When the scope specifier is invalid, don't even look for
2236 if (SS && SS->isSet()) {
2237 NestedNameSpecifier *NNS = SS->getScopeRep();
2238 if (NNS->getKind() == NestedNameSpecifier::Super)
2239 return LookupInSuper(R, NNS->getAsRecordDecl());
2241 if (DeclContext *DC = computeDeclContext(*SS, EnteringContext)) {
2242 // We have resolved the scope specifier to a particular declaration
2243 // contex, and will perform name lookup in that context.
2244 if (!DC->isDependentContext() && RequireCompleteDeclContext(*SS, DC))
2247 R.setContextRange(SS->getRange());
2248 return LookupQualifiedName(R, DC);
2251 // We could not resolve the scope specified to a specific declaration
2252 // context, which means that SS refers to an unknown specialization.
2253 // Name lookup can't find anything in this case.
2254 R.setNotFoundInCurrentInstantiation();
2255 R.setContextRange(SS->getRange());
2259 // Perform unqualified name lookup starting in the given scope.
2260 return LookupName(R, S, AllowBuiltinCreation);
2263 /// \brief Perform qualified name lookup into all base classes of the given
2266 /// \param R captures both the lookup criteria and any lookup results found.
2268 /// \param Class The context in which qualified name lookup will
2269 /// search. Name lookup will search in all base classes merging the results.
2271 /// @returns True if any decls were found (but possibly ambiguous)
2272 bool Sema::LookupInSuper(LookupResult &R, CXXRecordDecl *Class) {
2273 // The access-control rules we use here are essentially the rules for
2274 // doing a lookup in Class that just magically skipped the direct
2275 // members of Class itself. That is, the naming class is Class, and the
2276 // access includes the access of the base.
2277 for (const auto &BaseSpec : Class->bases()) {
2278 CXXRecordDecl *RD = cast<CXXRecordDecl>(
2279 BaseSpec.getType()->castAs<RecordType>()->getDecl());
2280 LookupResult Result(*this, R.getLookupNameInfo(), R.getLookupKind());
2281 Result.setBaseObjectType(Context.getRecordType(Class));
2282 LookupQualifiedName(Result, RD);
2284 // Copy the lookup results into the target, merging the base's access into
2286 for (auto I = Result.begin(), E = Result.end(); I != E; ++I) {
2287 R.addDecl(I.getDecl(),
2288 CXXRecordDecl::MergeAccess(BaseSpec.getAccessSpecifier(),
2292 Result.suppressDiagnostics();
2296 R.setNamingClass(Class);
2301 /// \brief Produce a diagnostic describing the ambiguity that resulted
2302 /// from name lookup.
2304 /// \param Result The result of the ambiguous lookup to be diagnosed.
2305 void Sema::DiagnoseAmbiguousLookup(LookupResult &Result) {
2306 assert(Result.isAmbiguous() && "Lookup result must be ambiguous");
2308 DeclarationName Name = Result.getLookupName();
2309 SourceLocation NameLoc = Result.getNameLoc();
2310 SourceRange LookupRange = Result.getContextRange();
2312 switch (Result.getAmbiguityKind()) {
2313 case LookupResult::AmbiguousBaseSubobjects: {
2314 CXXBasePaths *Paths = Result.getBasePaths();
2315 QualType SubobjectType = Paths->front().back().Base->getType();
2316 Diag(NameLoc, diag::err_ambiguous_member_multiple_subobjects)
2317 << Name << SubobjectType << getAmbiguousPathsDisplayString(*Paths)
2320 DeclContext::lookup_iterator Found = Paths->front().Decls.begin();
2321 while (isa<CXXMethodDecl>(*Found) &&
2322 cast<CXXMethodDecl>(*Found)->isStatic())
2325 Diag((*Found)->getLocation(), diag::note_ambiguous_member_found);
2329 case LookupResult::AmbiguousBaseSubobjectTypes: {
2330 Diag(NameLoc, diag::err_ambiguous_member_multiple_subobject_types)
2331 << Name << LookupRange;
2333 CXXBasePaths *Paths = Result.getBasePaths();
2334 std::set<Decl *> DeclsPrinted;
2335 for (CXXBasePaths::paths_iterator Path = Paths->begin(),
2336 PathEnd = Paths->end();
2337 Path != PathEnd; ++Path) {
2338 Decl *D = Path->Decls.front();
2339 if (DeclsPrinted.insert(D).second)
2340 Diag(D->getLocation(), diag::note_ambiguous_member_found);
2345 case LookupResult::AmbiguousTagHiding: {
2346 Diag(NameLoc, diag::err_ambiguous_tag_hiding) << Name << LookupRange;
2348 llvm::SmallPtrSet<NamedDecl*, 8> TagDecls;
2350 for (auto *D : Result)
2351 if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
2352 TagDecls.insert(TD);
2353 Diag(TD->getLocation(), diag::note_hidden_tag);
2356 for (auto *D : Result)
2357 if (!isa<TagDecl>(D))
2358 Diag(D->getLocation(), diag::note_hiding_object);
2360 // For recovery purposes, go ahead and implement the hiding.
2361 LookupResult::Filter F = Result.makeFilter();
2362 while (F.hasNext()) {
2363 if (TagDecls.count(F.next()))
2370 case LookupResult::AmbiguousReference: {
2371 Diag(NameLoc, diag::err_ambiguous_reference) << Name << LookupRange;
2373 for (auto *D : Result)
2374 Diag(D->getLocation(), diag::note_ambiguous_candidate) << D;
2381 struct AssociatedLookup {
2382 AssociatedLookup(Sema &S, SourceLocation InstantiationLoc,
2383 Sema::AssociatedNamespaceSet &Namespaces,
2384 Sema::AssociatedClassSet &Classes)
2385 : S(S), Namespaces(Namespaces), Classes(Classes),
2386 InstantiationLoc(InstantiationLoc) {
2390 Sema::AssociatedNamespaceSet &Namespaces;
2391 Sema::AssociatedClassSet &Classes;
2392 SourceLocation InstantiationLoc;
2394 } // end anonymous namespace
2397 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType T);
2399 static void CollectEnclosingNamespace(Sema::AssociatedNamespaceSet &Namespaces,
2401 // Add the associated namespace for this class.
2403 // We don't use DeclContext::getEnclosingNamespaceContext() as this may
2404 // be a locally scoped record.
2406 // We skip out of inline namespaces. The innermost non-inline namespace
2407 // contains all names of all its nested inline namespaces anyway, so we can
2408 // replace the entire inline namespace tree with its root.
2409 while (Ctx->isRecord() || Ctx->isTransparentContext() ||
2410 Ctx->isInlineNamespace())
2411 Ctx = Ctx->getParent();
2413 if (Ctx->isFileContext())
2414 Namespaces.insert(Ctx->getPrimaryContext());
2417 // \brief Add the associated classes and namespaces for argument-dependent
2418 // lookup that involves a template argument (C++ [basic.lookup.koenig]p2).
2420 addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
2421 const TemplateArgument &Arg) {
2422 // C++ [basic.lookup.koenig]p2, last bullet:
2424 switch (Arg.getKind()) {
2425 case TemplateArgument::Null:
2428 case TemplateArgument::Type:
2429 // [...] the namespaces and classes associated with the types of the
2430 // template arguments provided for template type parameters (excluding
2431 // template template parameters)
2432 addAssociatedClassesAndNamespaces(Result, Arg.getAsType());
2435 case TemplateArgument::Template:
2436 case TemplateArgument::TemplateExpansion: {
2437 // [...] the namespaces in which any template template arguments are
2438 // defined; and the classes in which any member templates used as
2439 // template template arguments are defined.
2440 TemplateName Template = Arg.getAsTemplateOrTemplatePattern();
2441 if (ClassTemplateDecl *ClassTemplate
2442 = dyn_cast<ClassTemplateDecl>(Template.getAsTemplateDecl())) {
2443 DeclContext *Ctx = ClassTemplate->getDeclContext();
2444 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2445 Result.Classes.insert(EnclosingClass);
2446 // Add the associated namespace for this class.
2447 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2452 case TemplateArgument::Declaration:
2453 case TemplateArgument::Integral:
2454 case TemplateArgument::Expression:
2455 case TemplateArgument::NullPtr:
2456 // [Note: non-type template arguments do not contribute to the set of
2457 // associated namespaces. ]
2460 case TemplateArgument::Pack:
2461 for (const auto &P : Arg.pack_elements())
2462 addAssociatedClassesAndNamespaces(Result, P);
2467 // \brief Add the associated classes and namespaces for
2468 // argument-dependent lookup with an argument of class type
2469 // (C++ [basic.lookup.koenig]p2).
2471 addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
2472 CXXRecordDecl *Class) {
2474 // Just silently ignore anything whose name is __va_list_tag.
2475 if (Class->getDeclName() == Result.S.VAListTagName)
2478 // C++ [basic.lookup.koenig]p2:
2480 // -- If T is a class type (including unions), its associated
2481 // classes are: the class itself; the class of which it is a
2482 // member, if any; and its direct and indirect base
2483 // classes. Its associated namespaces are the namespaces in
2484 // which its associated classes are defined.
2486 // Add the class of which it is a member, if any.
2487 DeclContext *Ctx = Class->getDeclContext();
2488 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2489 Result.Classes.insert(EnclosingClass);
2490 // Add the associated namespace for this class.
2491 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2493 // Add the class itself. If we've already seen this class, we don't
2494 // need to visit base classes.
2496 // FIXME: That's not correct, we may have added this class only because it
2497 // was the enclosing class of another class, and in that case we won't have
2498 // added its base classes yet.
2499 if (!Result.Classes.insert(Class))
2502 // -- If T is a template-id, its associated namespaces and classes are
2503 // the namespace in which the template is defined; for member
2504 // templates, the member template's class; the namespaces and classes
2505 // associated with the types of the template arguments provided for
2506 // template type parameters (excluding template template parameters); the
2507 // namespaces in which any template template arguments are defined; and
2508 // the classes in which any member templates used as template template
2509 // arguments are defined. [Note: non-type template arguments do not
2510 // contribute to the set of associated namespaces. ]
2511 if (ClassTemplateSpecializationDecl *Spec
2512 = dyn_cast<ClassTemplateSpecializationDecl>(Class)) {
2513 DeclContext *Ctx = Spec->getSpecializedTemplate()->getDeclContext();
2514 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2515 Result.Classes.insert(EnclosingClass);
2516 // Add the associated namespace for this class.
2517 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2519 const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
2520 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
2521 addAssociatedClassesAndNamespaces(Result, TemplateArgs[I]);
2524 // Only recurse into base classes for complete types.
2525 if (!Result.S.isCompleteType(Result.InstantiationLoc,
2526 Result.S.Context.getRecordType(Class)))
2529 // Add direct and indirect base classes along with their associated
2531 SmallVector<CXXRecordDecl *, 32> Bases;
2532 Bases.push_back(Class);
2533 while (!Bases.empty()) {
2534 // Pop this class off the stack.
2535 Class = Bases.pop_back_val();
2537 // Visit the base classes.
2538 for (const auto &Base : Class->bases()) {
2539 const RecordType *BaseType = Base.getType()->getAs<RecordType>();
2540 // In dependent contexts, we do ADL twice, and the first time around,
2541 // the base type might be a dependent TemplateSpecializationType, or a
2542 // TemplateTypeParmType. If that happens, simply ignore it.
2543 // FIXME: If we want to support export, we probably need to add the
2544 // namespace of the template in a TemplateSpecializationType, or even
2545 // the classes and namespaces of known non-dependent arguments.
2548 CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(BaseType->getDecl());
2549 if (Result.Classes.insert(BaseDecl)) {
2550 // Find the associated namespace for this base class.
2551 DeclContext *BaseCtx = BaseDecl->getDeclContext();
2552 CollectEnclosingNamespace(Result.Namespaces, BaseCtx);
2554 // Make sure we visit the bases of this base class.
2555 if (BaseDecl->bases_begin() != BaseDecl->bases_end())
2556 Bases.push_back(BaseDecl);
2562 // \brief Add the associated classes and namespaces for
2563 // argument-dependent lookup with an argument of type T
2564 // (C++ [basic.lookup.koenig]p2).
2566 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType Ty) {
2567 // C++ [basic.lookup.koenig]p2:
2569 // For each argument type T in the function call, there is a set
2570 // of zero or more associated namespaces and a set of zero or more
2571 // associated classes to be considered. The sets of namespaces and
2572 // classes is determined entirely by the types of the function
2573 // arguments (and the namespace of any template template
2574 // argument). Typedef names and using-declarations used to specify
2575 // the types do not contribute to this set. The sets of namespaces
2576 // and classes are determined in the following way:
2578 SmallVector<const Type *, 16> Queue;
2579 const Type *T = Ty->getCanonicalTypeInternal().getTypePtr();
2582 switch (T->getTypeClass()) {
2584 #define TYPE(Class, Base)
2585 #define DEPENDENT_TYPE(Class, Base) case Type::Class:
2586 #define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2587 #define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
2588 #define ABSTRACT_TYPE(Class, Base)
2589 #include "clang/AST/TypeNodes.def"
2590 // T is canonical. We can also ignore dependent types because
2591 // we don't need to do ADL at the definition point, but if we
2592 // wanted to implement template export (or if we find some other
2593 // use for associated classes and namespaces...) this would be
2597 // -- If T is a pointer to U or an array of U, its associated
2598 // namespaces and classes are those associated with U.
2600 T = cast<PointerType>(T)->getPointeeType().getTypePtr();
2602 case Type::ConstantArray:
2603 case Type::IncompleteArray:
2604 case Type::VariableArray:
2605 T = cast<ArrayType>(T)->getElementType().getTypePtr();
2608 // -- If T is a fundamental type, its associated sets of
2609 // namespaces and classes are both empty.
2613 // -- If T is a class type (including unions), its associated
2614 // classes are: the class itself; the class of which it is a
2615 // member, if any; and its direct and indirect base
2616 // classes. Its associated namespaces are the namespaces in
2617 // which its associated classes are defined.
2618 case Type::Record: {
2619 CXXRecordDecl *Class =
2620 cast<CXXRecordDecl>(cast<RecordType>(T)->getDecl());
2621 addAssociatedClassesAndNamespaces(Result, Class);
2625 // -- If T is an enumeration type, its associated namespace is
2626 // the namespace in which it is defined. If it is class
2627 // member, its associated class is the member's class; else
2628 // it has no associated class.
2630 EnumDecl *Enum = cast<EnumType>(T)->getDecl();
2632 DeclContext *Ctx = Enum->getDeclContext();
2633 if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2634 Result.Classes.insert(EnclosingClass);
2636 // Add the associated namespace for this class.
2637 CollectEnclosingNamespace(Result.Namespaces, Ctx);
2642 // -- If T is a function type, its associated namespaces and
2643 // classes are those associated with the function parameter
2644 // types and those associated with the return type.
2645 case Type::FunctionProto: {
2646 const FunctionProtoType *Proto = cast<FunctionProtoType>(T);
2647 for (const auto &Arg : Proto->param_types())
2648 Queue.push_back(Arg.getTypePtr());
2651 case Type::FunctionNoProto: {
2652 const FunctionType *FnType = cast<FunctionType>(T);
2653 T = FnType->getReturnType().getTypePtr();
2657 // -- If T is a pointer to a member function of a class X, its
2658 // associated namespaces and classes are those associated
2659 // with the function parameter types and return type,
2660 // together with those associated with X.
2662 // -- If T is a pointer to a data member of class X, its
2663 // associated namespaces and classes are those associated
2664 // with the member type together with those associated with
2666 case Type::MemberPointer: {
2667 const MemberPointerType *MemberPtr = cast<MemberPointerType>(T);
2669 // Queue up the class type into which this points.
2670 Queue.push_back(MemberPtr->getClass());
2672 // And directly continue with the pointee type.
2673 T = MemberPtr->getPointeeType().getTypePtr();
2677 // As an extension, treat this like a normal pointer.
2678 case Type::BlockPointer:
2679 T = cast<BlockPointerType>(T)->getPointeeType().getTypePtr();
2682 // References aren't covered by the standard, but that's such an
2683 // obvious defect that we cover them anyway.
2684 case Type::LValueReference:
2685 case Type::RValueReference:
2686 T = cast<ReferenceType>(T)->getPointeeType().getTypePtr();
2689 // These are fundamental types.
2691 case Type::ExtVector:
2695 // Non-deduced auto types only get here for error cases.
2699 // If T is an Objective-C object or interface type, or a pointer to an
2700 // object or interface type, the associated namespace is the global
2702 case Type::ObjCObject:
2703 case Type::ObjCInterface:
2704 case Type::ObjCObjectPointer:
2705 Result.Namespaces.insert(Result.S.Context.getTranslationUnitDecl());
2708 // Atomic types are just wrappers; use the associations of the
2711 T = cast<AtomicType>(T)->getValueType().getTypePtr();
2714 T = cast<PipeType>(T)->getElementType().getTypePtr();
2720 T = Queue.pop_back_val();
2724 /// \brief Find the associated classes and namespaces for
2725 /// argument-dependent lookup for a call with the given set of
2728 /// This routine computes the sets of associated classes and associated
2729 /// namespaces searched by argument-dependent lookup
2730 /// (C++ [basic.lookup.argdep]) for a given set of arguments.
2731 void Sema::FindAssociatedClassesAndNamespaces(
2732 SourceLocation InstantiationLoc, ArrayRef<Expr *> Args,
2733 AssociatedNamespaceSet &AssociatedNamespaces,
2734 AssociatedClassSet &AssociatedClasses) {
2735 AssociatedNamespaces.clear();
2736 AssociatedClasses.clear();
2738 AssociatedLookup Result(*this, InstantiationLoc,
2739 AssociatedNamespaces, AssociatedClasses);
2741 // C++ [basic.lookup.koenig]p2:
2742 // For each argument type T in the function call, there is a set
2743 // of zero or more associated namespaces and a set of zero or more
2744 // associated classes to be considered. The sets of namespaces and
2745 // classes is determined entirely by the types of the function
2746 // arguments (and the namespace of any template template
2748 for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) {
2749 Expr *Arg = Args[ArgIdx];
2751 if (Arg->getType() != Context.OverloadTy) {
2752 addAssociatedClassesAndNamespaces(Result, Arg->getType());
2756 // [...] In addition, if the argument is the name or address of a
2757 // set of overloaded functions and/or function templates, its
2758 // associated classes and namespaces are the union of those
2759 // associated with each of the members of the set: the namespace
2760 // in which the function or function template is defined and the
2761 // classes and namespaces associated with its (non-dependent)
2762 // parameter types and return type.
2763 Arg = Arg->IgnoreParens();
2764 if (UnaryOperator *unaryOp = dyn_cast<UnaryOperator>(Arg))
2765 if (unaryOp->getOpcode() == UO_AddrOf)
2766 Arg = unaryOp->getSubExpr();
2768 UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Arg);
2771 for (const auto *D : ULE->decls()) {
2772 // Look through any using declarations to find the underlying function.
2773 const FunctionDecl *FDecl = D->getUnderlyingDecl()->getAsFunction();
2775 // Add the classes and namespaces associated with the parameter
2776 // types and return type of this function.
2777 addAssociatedClassesAndNamespaces(Result, FDecl->getType());
2782 NamedDecl *Sema::LookupSingleName(Scope *S, DeclarationName Name,
2784 LookupNameKind NameKind,
2785 RedeclarationKind Redecl) {
2786 LookupResult R(*this, Name, Loc, NameKind, Redecl);
2788 return R.getAsSingle<NamedDecl>();
2791 /// \brief Find the protocol with the given name, if any.
2792 ObjCProtocolDecl *Sema::LookupProtocol(IdentifierInfo *II,
2793 SourceLocation IdLoc,
2794 RedeclarationKind Redecl) {
2795 Decl *D = LookupSingleName(TUScope, II, IdLoc,
2796 LookupObjCProtocolName, Redecl);
2797 return cast_or_null<ObjCProtocolDecl>(D);
2800 void Sema::LookupOverloadedOperatorName(OverloadedOperatorKind Op, Scope *S,
2801 QualType T1, QualType T2,
2802 UnresolvedSetImpl &Functions) {
2803 // C++ [over.match.oper]p3:
2804 // -- The set of non-member candidates is the result of the
2805 // unqualified lookup of operator@ in the context of the
2806 // expression according to the usual rules for name lookup in
2807 // unqualified function calls (3.4.2) except that all member
2808 // functions are ignored.
2809 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op);
2810 LookupResult Operators(*this, OpName, SourceLocation(), LookupOperatorName);
2811 LookupName(Operators, S);
2813 assert(!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous");
2814 Functions.append(Operators.begin(), Operators.end());
2817 Sema::SpecialMemberOverloadResult *Sema::LookupSpecialMember(CXXRecordDecl *RD,
2818 CXXSpecialMember SM,
2823 bool VolatileThis) {
2824 assert(CanDeclareSpecialMemberFunction(RD) &&
2825 "doing special member lookup into record that isn't fully complete");
2826 RD = RD->getDefinition();
2827 if (RValueThis || ConstThis || VolatileThis)
2828 assert((SM == CXXCopyAssignment || SM == CXXMoveAssignment) &&
2829 "constructors and destructors always have unqualified lvalue this");
2830 if (ConstArg || VolatileArg)
2831 assert((SM != CXXDefaultConstructor && SM != CXXDestructor) &&
2832 "parameter-less special members can't have qualified arguments");
2834 llvm::FoldingSetNodeID ID;
2837 ID.AddInteger(ConstArg);
2838 ID.AddInteger(VolatileArg);
2839 ID.AddInteger(RValueThis);
2840 ID.AddInteger(ConstThis);
2841 ID.AddInteger(VolatileThis);
2844 SpecialMemberOverloadResult *Result =
2845 SpecialMemberCache.FindNodeOrInsertPos(ID, InsertPoint);
2847 // This was already cached
2851 Result = BumpAlloc.Allocate<SpecialMemberOverloadResult>();
2852 Result = new (Result) SpecialMemberOverloadResult(ID);
2853 SpecialMemberCache.InsertNode(Result, InsertPoint);
2855 if (SM == CXXDestructor) {
2856 if (RD->needsImplicitDestructor())
2857 DeclareImplicitDestructor(RD);
2858 CXXDestructorDecl *DD = RD->getDestructor();
2859 assert(DD && "record without a destructor");
2860 Result->setMethod(DD);
2861 Result->setKind(DD->isDeleted() ?
2862 SpecialMemberOverloadResult::NoMemberOrDeleted :
2863 SpecialMemberOverloadResult::Success);
2867 // Prepare for overload resolution. Here we construct a synthetic argument
2868 // if necessary and make sure that implicit functions are declared.
2869 CanQualType CanTy = Context.getCanonicalType(Context.getTagDeclType(RD));
2870 DeclarationName Name;
2871 Expr *Arg = nullptr;
2874 QualType ArgType = CanTy;
2875 ExprValueKind VK = VK_LValue;
2877 if (SM == CXXDefaultConstructor) {
2878 Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
2880 if (RD->needsImplicitDefaultConstructor())
2881 DeclareImplicitDefaultConstructor(RD);
2883 if (SM == CXXCopyConstructor || SM == CXXMoveConstructor) {
2884 Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
2885 if (RD->needsImplicitCopyConstructor())
2886 DeclareImplicitCopyConstructor(RD);
2887 if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveConstructor())
2888 DeclareImplicitMoveConstructor(RD);
2890 Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
2891 if (RD->needsImplicitCopyAssignment())
2892 DeclareImplicitCopyAssignment(RD);
2893 if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveAssignment())
2894 DeclareImplicitMoveAssignment(RD);
2900 ArgType.addVolatile();
2902 // This isn't /really/ specified by the standard, but it's implied
2903 // we should be working from an RValue in the case of move to ensure
2904 // that we prefer to bind to rvalue references, and an LValue in the
2905 // case of copy to ensure we don't bind to rvalue references.
2906 // Possibly an XValue is actually correct in the case of move, but
2907 // there is no semantic difference for class types in this restricted
2909 if (SM == CXXCopyConstructor || SM == CXXCopyAssignment)
2915 OpaqueValueExpr FakeArg(SourceLocation(), ArgType, VK);
2917 if (SM != CXXDefaultConstructor) {
2922 // Create the object argument
2923 QualType ThisTy = CanTy;
2927 ThisTy.addVolatile();
2928 Expr::Classification Classification =
2929 OpaqueValueExpr(SourceLocation(), ThisTy,
2930 RValueThis ? VK_RValue : VK_LValue).Classify(Context);
2932 // Now we perform lookup on the name we computed earlier and do overload
2933 // resolution. Lookup is only performed directly into the class since there
2934 // will always be a (possibly implicit) declaration to shadow any others.
2935 OverloadCandidateSet OCS(RD->getLocation(), OverloadCandidateSet::CSK_Normal);
2936 DeclContext::lookup_result R = RD->lookup(Name);
2939 // We might have no default constructor because we have a lambda's closure
2940 // type, rather than because there's some other declared constructor.
2941 // Every class has a copy/move constructor, copy/move assignment, and
2943 assert(SM == CXXDefaultConstructor &&
2944 "lookup for a constructor or assignment operator was empty");
2945 Result->setMethod(nullptr);
2946 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
2950 // Copy the candidates as our processing of them may load new declarations
2951 // from an external source and invalidate lookup_result.
2952 SmallVector<NamedDecl *, 8> Candidates(R.begin(), R.end());
2954 for (NamedDecl *CandDecl : Candidates) {
2955 if (CandDecl->isInvalidDecl())
2958 DeclAccessPair Cand = DeclAccessPair::make(CandDecl, AS_public);
2959 auto CtorInfo = getConstructorInfo(Cand);
2960 if (CXXMethodDecl *M = dyn_cast<CXXMethodDecl>(Cand->getUnderlyingDecl())) {
2961 if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
2962 AddMethodCandidate(M, Cand, RD, ThisTy, Classification,
2963 llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
2965 AddOverloadCandidate(CtorInfo.Constructor, CtorInfo.FoundDecl,
2966 llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
2968 AddOverloadCandidate(M, Cand, llvm::makeArrayRef(&Arg, NumArgs), OCS,
2970 } else if (FunctionTemplateDecl *Tmpl =
2971 dyn_cast<FunctionTemplateDecl>(Cand->getUnderlyingDecl())) {
2972 if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
2973 AddMethodTemplateCandidate(
2974 Tmpl, Cand, RD, nullptr, ThisTy, Classification,
2975 llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
2977 AddTemplateOverloadCandidate(
2978 CtorInfo.ConstructorTmpl, CtorInfo.FoundDecl, nullptr,
2979 llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
2981 AddTemplateOverloadCandidate(
2982 Tmpl, Cand, nullptr, llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
2984 assert(isa<UsingDecl>(Cand.getDecl()) &&
2985 "illegal Kind of operator = Decl");
2989 OverloadCandidateSet::iterator Best;
2990 switch (OCS.BestViableFunction(*this, SourceLocation(), Best)) {
2992 Result->setMethod(cast<CXXMethodDecl>(Best->Function));
2993 Result->setKind(SpecialMemberOverloadResult::Success);
2997 Result->setMethod(cast<CXXMethodDecl>(Best->Function));
2998 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
3002 Result->setMethod(nullptr);
3003 Result->setKind(SpecialMemberOverloadResult::Ambiguous);
3006 case OR_No_Viable_Function:
3007 Result->setMethod(nullptr);
3008 Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
3015 /// \brief Look up the default constructor for the given class.
3016 CXXConstructorDecl *Sema::LookupDefaultConstructor(CXXRecordDecl *Class) {
3017 SpecialMemberOverloadResult *Result =
3018 LookupSpecialMember(Class, CXXDefaultConstructor, false, false, false,
3021 return cast_or_null<CXXConstructorDecl>(Result->getMethod());
3024 /// \brief Look up the copying constructor for the given class.
3025 CXXConstructorDecl *Sema::LookupCopyingConstructor(CXXRecordDecl *Class,
3027 assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3028 "non-const, non-volatile qualifiers for copy ctor arg");
3029 SpecialMemberOverloadResult *Result =
3030 LookupSpecialMember(Class, CXXCopyConstructor, Quals & Qualifiers::Const,
3031 Quals & Qualifiers::Volatile, false, false, false);
3033 return cast_or_null<CXXConstructorDecl>(Result->getMethod());
3036 /// \brief Look up the moving constructor for the given class.
3037 CXXConstructorDecl *Sema::LookupMovingConstructor(CXXRecordDecl *Class,
3039 SpecialMemberOverloadResult *Result =
3040 LookupSpecialMember(Class, CXXMoveConstructor, Quals & Qualifiers::Const,
3041 Quals & Qualifiers::Volatile, false, false, false);
3043 return cast_or_null<CXXConstructorDecl>(Result->getMethod());
3046 /// \brief Look up the constructors for the given class.
3047 DeclContext::lookup_result Sema::LookupConstructors(CXXRecordDecl *Class) {
3048 // If the implicit constructors have not yet been declared, do so now.
3049 if (CanDeclareSpecialMemberFunction(Class)) {
3050 if (Class->needsImplicitDefaultConstructor())
3051 DeclareImplicitDefaultConstructor(Class);
3052 if (Class->needsImplicitCopyConstructor())
3053 DeclareImplicitCopyConstructor(Class);
3054 if (getLangOpts().CPlusPlus11 && Class->needsImplicitMoveConstructor())
3055 DeclareImplicitMoveConstructor(Class);
3058 CanQualType T = Context.getCanonicalType(Context.getTypeDeclType(Class));
3059 DeclarationName Name = Context.DeclarationNames.getCXXConstructorName(T);
3060 return Class->lookup(Name);
3063 /// \brief Look up the copying assignment operator for the given class.
3064 CXXMethodDecl *Sema::LookupCopyingAssignment(CXXRecordDecl *Class,
3065 unsigned Quals, bool RValueThis,
3066 unsigned ThisQuals) {
3067 assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3068 "non-const, non-volatile qualifiers for copy assignment arg");
3069 assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3070 "non-const, non-volatile qualifiers for copy assignment this");
3071 SpecialMemberOverloadResult *Result =
3072 LookupSpecialMember(Class, CXXCopyAssignment, Quals & Qualifiers::Const,
3073 Quals & Qualifiers::Volatile, RValueThis,
3074 ThisQuals & Qualifiers::Const,
3075 ThisQuals & Qualifiers::Volatile);
3077 return Result->getMethod();
3080 /// \brief Look up the moving assignment operator for the given class.
3081 CXXMethodDecl *Sema::LookupMovingAssignment(CXXRecordDecl *Class,
3084 unsigned ThisQuals) {
3085 assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3086 "non-const, non-volatile qualifiers for copy assignment this");
3087 SpecialMemberOverloadResult *Result =
3088 LookupSpecialMember(Class, CXXMoveAssignment, Quals & Qualifiers::Const,
3089 Quals & Qualifiers::Volatile, RValueThis,
3090 ThisQuals & Qualifiers::Const,
3091 ThisQuals & Qualifiers::Volatile);
3093 return Result->getMethod();
3096 /// \brief Look for the destructor of the given class.
3098 /// During semantic analysis, this routine should be used in lieu of
3099 /// CXXRecordDecl::getDestructor().
3101 /// \returns The destructor for this class.
3102 CXXDestructorDecl *Sema::LookupDestructor(CXXRecordDecl *Class) {
3103 return cast<CXXDestructorDecl>(LookupSpecialMember(Class, CXXDestructor,
3104 false, false, false,
3105 false, false)->getMethod());
3108 /// LookupLiteralOperator - Determine which literal operator should be used for
3109 /// a user-defined literal, per C++11 [lex.ext].
3111 /// Normal overload resolution is not used to select which literal operator to
3112 /// call for a user-defined literal. Look up the provided literal operator name,
3113 /// and filter the results to the appropriate set for the given argument types.
3114 Sema::LiteralOperatorLookupResult
3115 Sema::LookupLiteralOperator(Scope *S, LookupResult &R,
3116 ArrayRef<QualType> ArgTys,
3117 bool AllowRaw, bool AllowTemplate,
3118 bool AllowStringTemplate) {
3120 assert(R.getResultKind() != LookupResult::Ambiguous &&
3121 "literal operator lookup can't be ambiguous");
3123 // Filter the lookup results appropriately.
3124 LookupResult::Filter F = R.makeFilter();
3126 bool FoundRaw = false;
3127 bool FoundTemplate = false;
3128 bool FoundStringTemplate = false;
3129 bool FoundExactMatch = false;
3131 while (F.hasNext()) {
3133 if (UsingShadowDecl *USD = dyn_cast<UsingShadowDecl>(D))
3134 D = USD->getTargetDecl();
3136 // If the declaration we found is invalid, skip it.
3137 if (D->isInvalidDecl()) {
3143 bool IsTemplate = false;
3144 bool IsStringTemplate = false;
3145 bool IsExactMatch = false;
3147 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
3148 if (FD->getNumParams() == 1 &&
3149 FD->getParamDecl(0)->getType()->getAs<PointerType>())
3151 else if (FD->getNumParams() == ArgTys.size()) {
3152 IsExactMatch = true;
3153 for (unsigned ArgIdx = 0; ArgIdx != ArgTys.size(); ++ArgIdx) {
3154 QualType ParamTy = FD->getParamDecl(ArgIdx)->getType();
3155 if (!Context.hasSameUnqualifiedType(ArgTys[ArgIdx], ParamTy)) {
3156 IsExactMatch = false;
3162 if (FunctionTemplateDecl *FD = dyn_cast<FunctionTemplateDecl>(D)) {
3163 TemplateParameterList *Params = FD->getTemplateParameters();
3164 if (Params->size() == 1)
3167 IsStringTemplate = true;
3171 FoundExactMatch = true;
3173 AllowTemplate = false;
3174 AllowStringTemplate = false;
3175 if (FoundRaw || FoundTemplate || FoundStringTemplate) {
3176 // Go through again and remove the raw and template decls we've
3179 FoundRaw = FoundTemplate = FoundStringTemplate = false;
3181 } else if (AllowRaw && IsRaw) {
3183 } else if (AllowTemplate && IsTemplate) {
3184 FoundTemplate = true;
3185 } else if (AllowStringTemplate && IsStringTemplate) {
3186 FoundStringTemplate = true;
3194 // C++11 [lex.ext]p3, p4: If S contains a literal operator with a matching
3195 // parameter type, that is used in preference to a raw literal operator
3196 // or literal operator template.
3197 if (FoundExactMatch)
3200 // C++11 [lex.ext]p3, p4: S shall contain a raw literal operator or a literal
3201 // operator template, but not both.
3202 if (FoundRaw && FoundTemplate) {
3203 Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call) << R.getLookupName();
3204 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
3205 NoteOverloadCandidate(*I, (*I)->getUnderlyingDecl()->getAsFunction());
3213 return LOLR_Template;
3215 if (FoundStringTemplate)
3216 return LOLR_StringTemplate;
3218 // Didn't find anything we could use.
3219 Diag(R.getNameLoc(), diag::err_ovl_no_viable_literal_operator)
3220 << R.getLookupName() << (int)ArgTys.size() << ArgTys[0]
3221 << (ArgTys.size() == 2 ? ArgTys[1] : QualType()) << AllowRaw
3222 << (AllowTemplate || AllowStringTemplate);
3226 void ADLResult::insert(NamedDecl *New) {
3227 NamedDecl *&Old = Decls[cast<NamedDecl>(New->getCanonicalDecl())];
3229 // If we haven't yet seen a decl for this key, or the last decl
3230 // was exactly this one, we're done.
3231 if (Old == nullptr || Old == New) {
3236 // Otherwise, decide which is a more recent redeclaration.
3237 FunctionDecl *OldFD = Old->getAsFunction();
3238 FunctionDecl *NewFD = New->getAsFunction();
3240 FunctionDecl *Cursor = NewFD;
3242 Cursor = Cursor->getPreviousDecl();
3244 // If we got to the end without finding OldFD, OldFD is the newer
3245 // declaration; leave things as they are.
3246 if (!Cursor) return;
3248 // If we do find OldFD, then NewFD is newer.
3249 if (Cursor == OldFD) break;
3251 // Otherwise, keep looking.
3257 void Sema::ArgumentDependentLookup(DeclarationName Name, SourceLocation Loc,
3258 ArrayRef<Expr *> Args, ADLResult &Result) {
3259 // Find all of the associated namespaces and classes based on the
3260 // arguments we have.
3261 AssociatedNamespaceSet AssociatedNamespaces;
3262 AssociatedClassSet AssociatedClasses;
3263 FindAssociatedClassesAndNamespaces(Loc, Args,
3264 AssociatedNamespaces,
3267 // C++ [basic.lookup.argdep]p3:
3268 // Let X be the lookup set produced by unqualified lookup (3.4.1)
3269 // and let Y be the lookup set produced by argument dependent
3270 // lookup (defined as follows). If X contains [...] then Y is
3271 // empty. Otherwise Y is the set of declarations found in the
3272 // namespaces associated with the argument types as described
3273 // below. The set of declarations found by the lookup of the name
3274 // is the union of X and Y.
3276 // Here, we compute Y and add its members to the overloaded
3278 for (auto *NS : AssociatedNamespaces) {
3279 // When considering an associated namespace, the lookup is the
3280 // same as the lookup performed when the associated namespace is
3281 // used as a qualifier (3.4.3.2) except that:
3283 // -- Any using-directives in the associated namespace are
3286 // -- Any namespace-scope friend functions declared in
3287 // associated classes are visible within their respective
3288 // namespaces even if they are not visible during an ordinary
3290 DeclContext::lookup_result R = NS->lookup(Name);
3292 // If the only declaration here is an ordinary friend, consider
3293 // it only if it was declared in an associated classes.
3294 if ((D->getIdentifierNamespace() & Decl::IDNS_Ordinary) == 0) {
3295 // If it's neither ordinarily visible nor a friend, we can't find it.
3296 if ((D->getIdentifierNamespace() & Decl::IDNS_OrdinaryFriend) == 0)
3299 bool DeclaredInAssociatedClass = false;
3300 for (Decl *DI = D; DI; DI = DI->getPreviousDecl()) {
3301 DeclContext *LexDC = DI->getLexicalDeclContext();
3302 if (isa<CXXRecordDecl>(LexDC) &&
3303 AssociatedClasses.count(cast<CXXRecordDecl>(LexDC)) &&
3304 isVisible(cast<NamedDecl>(DI))) {
3305 DeclaredInAssociatedClass = true;
3309 if (!DeclaredInAssociatedClass)
3313 if (isa<UsingShadowDecl>(D))
3314 D = cast<UsingShadowDecl>(D)->getTargetDecl();
3316 if (!isa<FunctionDecl>(D) && !isa<FunctionTemplateDecl>(D))
3319 if (!isVisible(D) && !(D = findAcceptableDecl(*this, D)))
3327 //----------------------------------------------------------------------------
3328 // Search for all visible declarations.
3329 //----------------------------------------------------------------------------
3330 VisibleDeclConsumer::~VisibleDeclConsumer() { }
3332 bool VisibleDeclConsumer::includeHiddenDecls() const { return false; }
3336 class ShadowContextRAII;
3338 class VisibleDeclsRecord {
3340 /// \brief An entry in the shadow map, which is optimized to store a
3341 /// single declaration (the common case) but can also store a list
3342 /// of declarations.
3343 typedef llvm::TinyPtrVector<NamedDecl*> ShadowMapEntry;
3346 /// \brief A mapping from declaration names to the declarations that have
3347 /// this name within a particular scope.
3348 typedef llvm::DenseMap<DeclarationName, ShadowMapEntry> ShadowMap;
3350 /// \brief A list of shadow maps, which is used to model name hiding.
3351 std::list<ShadowMap> ShadowMaps;
3353 /// \brief The declaration contexts we have already visited.
3354 llvm::SmallPtrSet<DeclContext *, 8> VisitedContexts;
3356 friend class ShadowContextRAII;
3359 /// \brief Determine whether we have already visited this context
3360 /// (and, if not, note that we are going to visit that context now).
3361 bool visitedContext(DeclContext *Ctx) {
3362 return !VisitedContexts.insert(Ctx).second;
3365 bool alreadyVisitedContext(DeclContext *Ctx) {
3366 return VisitedContexts.count(Ctx);
3369 /// \brief Determine whether the given declaration is hidden in the
3372 /// \returns the declaration that hides the given declaration, or
3373 /// NULL if no such declaration exists.
3374 NamedDecl *checkHidden(NamedDecl *ND);
3376 /// \brief Add a declaration to the current shadow map.
3377 void add(NamedDecl *ND) {
3378 ShadowMaps.back()[ND->getDeclName()].push_back(ND);
3382 /// \brief RAII object that records when we've entered a shadow context.
3383 class ShadowContextRAII {
3384 VisibleDeclsRecord &Visible;
3386 typedef VisibleDeclsRecord::ShadowMap ShadowMap;
3389 ShadowContextRAII(VisibleDeclsRecord &Visible) : Visible(Visible) {
3390 Visible.ShadowMaps.emplace_back();
3393 ~ShadowContextRAII() {
3394 Visible.ShadowMaps.pop_back();
3398 } // end anonymous namespace
3400 NamedDecl *VisibleDeclsRecord::checkHidden(NamedDecl *ND) {
3401 unsigned IDNS = ND->getIdentifierNamespace();
3402 std::list<ShadowMap>::reverse_iterator SM = ShadowMaps.rbegin();
3403 for (std::list<ShadowMap>::reverse_iterator SMEnd = ShadowMaps.rend();
3404 SM != SMEnd; ++SM) {
3405 ShadowMap::iterator Pos = SM->find(ND->getDeclName());
3406 if (Pos == SM->end())
3409 for (auto *D : Pos->second) {
3410 // A tag declaration does not hide a non-tag declaration.
3411 if (D->hasTagIdentifierNamespace() &&
3412 (IDNS & (Decl::IDNS_Member | Decl::IDNS_Ordinary |
3413 Decl::IDNS_ObjCProtocol)))
3416 // Protocols are in distinct namespaces from everything else.
3417 if (((D->getIdentifierNamespace() & Decl::IDNS_ObjCProtocol)
3418 || (IDNS & Decl::IDNS_ObjCProtocol)) &&
3419 D->getIdentifierNamespace() != IDNS)
3422 // Functions and function templates in the same scope overload
3423 // rather than hide. FIXME: Look for hiding based on function
3425 if (D->getUnderlyingDecl()->isFunctionOrFunctionTemplate() &&
3426 ND->getUnderlyingDecl()->isFunctionOrFunctionTemplate() &&
3427 SM == ShadowMaps.rbegin())
3430 // We've found a declaration that hides this one.
3438 static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
3439 bool QualifiedNameLookup,
3441 VisibleDeclConsumer &Consumer,
3442 VisibleDeclsRecord &Visited) {
3446 // Make sure we don't visit the same context twice.
3447 if (Visited.visitedContext(Ctx->getPrimaryContext()))
3450 // Outside C++, lookup results for the TU live on identifiers.
3451 if (isa<TranslationUnitDecl>(Ctx) &&
3452 !Result.getSema().getLangOpts().CPlusPlus) {
3453 auto &S = Result.getSema();
3454 auto &Idents = S.Context.Idents;
3456 // Ensure all external identifiers are in the identifier table.
3457 if (IdentifierInfoLookup *External = Idents.getExternalIdentifierLookup()) {
3458 std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
3459 for (StringRef Name = Iter->Next(); !Name.empty(); Name = Iter->Next())
3463 // Walk all lookup results in the TU for each identifier.
3464 for (const auto &Ident : Idents) {
3465 for (auto I = S.IdResolver.begin(Ident.getValue()),
3466 E = S.IdResolver.end();
3468 if (S.IdResolver.isDeclInScope(*I, Ctx)) {
3469 if (NamedDecl *ND = Result.getAcceptableDecl(*I)) {
3470 Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
3480 if (CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(Ctx))
3481 Result.getSema().ForceDeclarationOfImplicitMembers(Class);
3483 // Enumerate all of the results in this context.
3484 for (DeclContextLookupResult R : Ctx->lookups()) {
3486 if (auto *ND = Result.getAcceptableDecl(D)) {
3487 Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
3493 // Traverse using directives for qualified name lookup.
3494 if (QualifiedNameLookup) {
3495 ShadowContextRAII Shadow(Visited);
3496 for (auto I : Ctx->using_directives()) {
3497 LookupVisibleDecls(I->getNominatedNamespace(), Result,
3498 QualifiedNameLookup, InBaseClass, Consumer, Visited);
3502 // Traverse the contexts of inherited C++ classes.
3503 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) {
3504 if (!Record->hasDefinition())
3507 for (const auto &B : Record->bases()) {
3508 QualType BaseType = B.getType();
3510 // Don't look into dependent bases, because name lookup can't look
3512 if (BaseType->isDependentType())
3515 const RecordType *Record = BaseType->getAs<RecordType>();
3519 // FIXME: It would be nice to be able to determine whether referencing
3520 // a particular member would be ambiguous. For example, given
3522 // struct A { int member; };
3523 // struct B { int member; };
3524 // struct C : A, B { };
3526 // void f(C *c) { c->### }
3528 // accessing 'member' would result in an ambiguity. However, we
3529 // could be smart enough to qualify the member with the base
3538 // Find results in this base class (and its bases).
3539 ShadowContextRAII Shadow(Visited);
3540 LookupVisibleDecls(Record->getDecl(), Result, QualifiedNameLookup,
3541 true, Consumer, Visited);
3545 // Traverse the contexts of Objective-C classes.
3546 if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>(Ctx)) {
3547 // Traverse categories.
3548 for (auto *Cat : IFace->visible_categories()) {
3549 ShadowContextRAII Shadow(Visited);
3550 LookupVisibleDecls(Cat, Result, QualifiedNameLookup, false,
3554 // Traverse protocols.
3555 for (auto *I : IFace->all_referenced_protocols()) {
3556 ShadowContextRAII Shadow(Visited);
3557 LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3561 // Traverse the superclass.
3562 if (IFace->getSuperClass()) {
3563 ShadowContextRAII Shadow(Visited);
3564 LookupVisibleDecls(IFace->getSuperClass(), Result, QualifiedNameLookup,
3565 true, Consumer, Visited);
3568 // If there is an implementation, traverse it. We do this to find
3569 // synthesized ivars.
3570 if (IFace->getImplementation()) {
3571 ShadowContextRAII Shadow(Visited);
3572 LookupVisibleDecls(IFace->getImplementation(), Result,
3573 QualifiedNameLookup, InBaseClass, Consumer, Visited);
3575 } else if (ObjCProtocolDecl *Protocol = dyn_cast<ObjCProtocolDecl>(Ctx)) {
3576 for (auto *I : Protocol->protocols()) {
3577 ShadowContextRAII Shadow(Visited);
3578 LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3581 } else if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(Ctx)) {
3582 for (auto *I : Category->protocols()) {
3583 ShadowContextRAII Shadow(Visited);
3584 LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3588 // If there is an implementation, traverse it.
3589 if (Category->getImplementation()) {
3590 ShadowContextRAII Shadow(Visited);
3591 LookupVisibleDecls(Category->getImplementation(), Result,
3592 QualifiedNameLookup, true, Consumer, Visited);
3597 static void LookupVisibleDecls(Scope *S, LookupResult &Result,
3598 UnqualUsingDirectiveSet &UDirs,
3599 VisibleDeclConsumer &Consumer,
3600 VisibleDeclsRecord &Visited) {
3604 if (!S->getEntity() ||
3606 !Visited.alreadyVisitedContext(S->getEntity())) ||
3607 (S->getEntity())->isFunctionOrMethod()) {
3608 FindLocalExternScope FindLocals(Result);
3609 // Walk through the declarations in this Scope.
3610 for (auto *D : S->decls()) {
3611 if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
3612 if ((ND = Result.getAcceptableDecl(ND))) {
3613 Consumer.FoundDecl(ND, Visited.checkHidden(ND), nullptr, false);
3619 // FIXME: C++ [temp.local]p8
3620 DeclContext *Entity = nullptr;
3621 if (S->getEntity()) {
3622 // Look into this scope's declaration context, along with any of its
3623 // parent lookup contexts (e.g., enclosing classes), up to the point
3624 // where we hit the context stored in the next outer scope.
3625 Entity = S->getEntity();
3626 DeclContext *OuterCtx = findOuterContext(S).first; // FIXME
3628 for (DeclContext *Ctx = Entity; Ctx && !Ctx->Equals(OuterCtx);
3629 Ctx = Ctx->getLookupParent()) {
3630 if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
3631 if (Method->isInstanceMethod()) {
3632 // For instance methods, look for ivars in the method's interface.
3633 LookupResult IvarResult(Result.getSema(), Result.getLookupName(),
3634 Result.getNameLoc(), Sema::LookupMemberName);
3635 if (ObjCInterfaceDecl *IFace = Method->getClassInterface()) {
3636 LookupVisibleDecls(IFace, IvarResult, /*QualifiedNameLookup=*/false,
3637 /*InBaseClass=*/false, Consumer, Visited);
3641 // We've already performed all of the name lookup that we need
3642 // to for Objective-C methods; the next context will be the
3647 if (Ctx->isFunctionOrMethod())
3650 LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/false,
3651 /*InBaseClass=*/false, Consumer, Visited);
3653 } else if (!S->getParent()) {
3654 // Look into the translation unit scope. We walk through the translation
3655 // unit's declaration context, because the Scope itself won't have all of
3656 // the declarations if we loaded a precompiled header.
3657 // FIXME: We would like the translation unit's Scope object to point to the
3658 // translation unit, so we don't need this special "if" branch. However,
3659 // doing so would force the normal C++ name-lookup code to look into the
3660 // translation unit decl when the IdentifierInfo chains would suffice.
3661 // Once we fix that problem (which is part of a more general "don't look
3662 // in DeclContexts unless we have to" optimization), we can eliminate this.
3663 Entity = Result.getSema().Context.getTranslationUnitDecl();
3664 LookupVisibleDecls(Entity, Result, /*QualifiedNameLookup=*/false,
3665 /*InBaseClass=*/false, Consumer, Visited);
3669 // Lookup visible declarations in any namespaces found by using
3671 for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(Entity))
3672 LookupVisibleDecls(const_cast<DeclContext *>(UUE.getNominatedNamespace()),
3673 Result, /*QualifiedNameLookup=*/false,
3674 /*InBaseClass=*/false, Consumer, Visited);
3677 // Lookup names in the parent scope.
3678 ShadowContextRAII Shadow(Visited);
3679 LookupVisibleDecls(S->getParent(), Result, UDirs, Consumer, Visited);
3682 void Sema::LookupVisibleDecls(Scope *S, LookupNameKind Kind,
3683 VisibleDeclConsumer &Consumer,
3684 bool IncludeGlobalScope) {
3685 // Determine the set of using directives available during
3686 // unqualified name lookup.
3688 UnqualUsingDirectiveSet UDirs;
3689 if (getLangOpts().CPlusPlus) {
3690 // Find the first namespace or translation-unit scope.
3691 while (S && !isNamespaceOrTranslationUnitScope(S))
3694 UDirs.visitScopeChain(Initial, S);
3698 // Look for visible declarations.
3699 LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
3700 Result.setAllowHidden(Consumer.includeHiddenDecls());
3701 VisibleDeclsRecord Visited;
3702 if (!IncludeGlobalScope)
3703 Visited.visitedContext(Context.getTranslationUnitDecl());
3704 ShadowContextRAII Shadow(Visited);
3705 ::LookupVisibleDecls(Initial, Result, UDirs, Consumer, Visited);
3708 void Sema::LookupVisibleDecls(DeclContext *Ctx, LookupNameKind Kind,
3709 VisibleDeclConsumer &Consumer,
3710 bool IncludeGlobalScope) {
3711 LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
3712 Result.setAllowHidden(Consumer.includeHiddenDecls());
3713 VisibleDeclsRecord Visited;
3714 if (!IncludeGlobalScope)
3715 Visited.visitedContext(Context.getTranslationUnitDecl());
3716 ShadowContextRAII Shadow(Visited);
3717 ::LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/true,
3718 /*InBaseClass=*/false, Consumer, Visited);
3721 /// LookupOrCreateLabel - Do a name lookup of a label with the specified name.
3722 /// If GnuLabelLoc is a valid source location, then this is a definition
3723 /// of an __label__ label name, otherwise it is a normal label definition
3725 LabelDecl *Sema::LookupOrCreateLabel(IdentifierInfo *II, SourceLocation Loc,
3726 SourceLocation GnuLabelLoc) {
3727 // Do a lookup to see if we have a label with this name already.
3728 NamedDecl *Res = nullptr;
3730 if (GnuLabelLoc.isValid()) {
3731 // Local label definitions always shadow existing labels.
3732 Res = LabelDecl::Create(Context, CurContext, Loc, II, GnuLabelLoc);
3733 Scope *S = CurScope;
3734 PushOnScopeChains(Res, S, true);
3735 return cast<LabelDecl>(Res);
3738 // Not a GNU local label.
3739 Res = LookupSingleName(CurScope, II, Loc, LookupLabel, NotForRedeclaration);
3740 // If we found a label, check to see if it is in the same context as us.
3741 // When in a Block, we don't want to reuse a label in an enclosing function.
3742 if (Res && Res->getDeclContext() != CurContext)
3745 // If not forward referenced or defined already, create the backing decl.
3746 Res = LabelDecl::Create(Context, CurContext, Loc, II);
3747 Scope *S = CurScope->getFnParent();
3748 assert(S && "Not in a function?");
3749 PushOnScopeChains(Res, S, true);
3751 return cast<LabelDecl>(Res);
3754 //===----------------------------------------------------------------------===//
3756 //===----------------------------------------------------------------------===//
3758 static bool isCandidateViable(CorrectionCandidateCallback &CCC,
3759 TypoCorrection &Candidate) {
3760 Candidate.setCallbackDistance(CCC.RankCandidate(Candidate));
3761 return Candidate.getEditDistance(false) != TypoCorrection::InvalidDistance;
3764 static void LookupPotentialTypoResult(Sema &SemaRef,
3766 IdentifierInfo *Name,
3767 Scope *S, CXXScopeSpec *SS,
3768 DeclContext *MemberContext,
3769 bool EnteringContext,
3770 bool isObjCIvarLookup,
3773 /// \brief Check whether the declarations found for a typo correction are
3774 /// visible, and if none of them are, convert the correction to an 'import
3775 /// a module' correction.
3776 static void checkCorrectionVisibility(Sema &SemaRef, TypoCorrection &TC) {
3777 if (TC.begin() == TC.end())
3780 TypoCorrection::decl_iterator DI = TC.begin(), DE = TC.end();
3782 for (/**/; DI != DE; ++DI)
3783 if (!LookupResult::isVisible(SemaRef, *DI))
3785 // Nothing to do if all decls are visible.
3789 llvm::SmallVector<NamedDecl*, 4> NewDecls(TC.begin(), DI);
3790 bool AnyVisibleDecls = !NewDecls.empty();
3792 for (/**/; DI != DE; ++DI) {
3793 NamedDecl *VisibleDecl = *DI;
3794 if (!LookupResult::isVisible(SemaRef, *DI))
3795 VisibleDecl = findAcceptableDecl(SemaRef, *DI);
3798 if (!AnyVisibleDecls) {
3799 // Found a visible decl, discard all hidden ones.
3800 AnyVisibleDecls = true;
3803 NewDecls.push_back(VisibleDecl);
3804 } else if (!AnyVisibleDecls && !(*DI)->isModulePrivate())
3805 NewDecls.push_back(*DI);
3808 if (NewDecls.empty())
3809 TC = TypoCorrection();
3811 TC.setCorrectionDecls(NewDecls);
3812 TC.setRequiresImport(!AnyVisibleDecls);
3816 // Fill the supplied vector with the IdentifierInfo pointers for each piece of
3817 // the given NestedNameSpecifier (i.e. given a NestedNameSpecifier "foo::bar::",
3818 // fill the vector with the IdentifierInfo pointers for "foo" and "bar").
3819 static void getNestedNameSpecifierIdentifiers(
3820 NestedNameSpecifier *NNS,
3821 SmallVectorImpl<const IdentifierInfo*> &Identifiers) {
3822 if (NestedNameSpecifier *Prefix = NNS->getPrefix())
3823 getNestedNameSpecifierIdentifiers(Prefix, Identifiers);
3825 Identifiers.clear();
3827 const IdentifierInfo *II = nullptr;
3829 switch (NNS->getKind()) {
3830 case NestedNameSpecifier::Identifier:
3831 II = NNS->getAsIdentifier();
3834 case NestedNameSpecifier::Namespace:
3835 if (NNS->getAsNamespace()->isAnonymousNamespace())
3837 II = NNS->getAsNamespace()->getIdentifier();
3840 case NestedNameSpecifier::NamespaceAlias:
3841 II = NNS->getAsNamespaceAlias()->getIdentifier();
3844 case NestedNameSpecifier::TypeSpecWithTemplate:
3845 case NestedNameSpecifier::TypeSpec:
3846 II = QualType(NNS->getAsType(), 0).getBaseTypeIdentifier();
3849 case NestedNameSpecifier::Global:
3850 case NestedNameSpecifier::Super:
3855 Identifiers.push_back(II);
3858 void TypoCorrectionConsumer::FoundDecl(NamedDecl *ND, NamedDecl *Hiding,
3859 DeclContext *Ctx, bool InBaseClass) {
3860 // Don't consider hidden names for typo correction.
3864 // Only consider entities with identifiers for names, ignoring
3865 // special names (constructors, overloaded operators, selectors,
3867 IdentifierInfo *Name = ND->getIdentifier();
3871 // Only consider visible declarations and declarations from modules with
3872 // names that exactly match.
3873 if (!LookupResult::isVisible(SemaRef, ND) && Name != Typo &&
3874 !findAcceptableDecl(SemaRef, ND))
3877 FoundName(Name->getName());
3880 void TypoCorrectionConsumer::FoundName(StringRef Name) {
3881 // Compute the edit distance between the typo and the name of this
3882 // entity, and add the identifier to the list of results.
3883 addName(Name, nullptr);
3886 void TypoCorrectionConsumer::addKeywordResult(StringRef Keyword) {
3887 // Compute the edit distance between the typo and this keyword,
3888 // and add the keyword to the list of results.
3889 addName(Keyword, nullptr, nullptr, true);
3892 void TypoCorrectionConsumer::addName(StringRef Name, NamedDecl *ND,
3893 NestedNameSpecifier *NNS, bool isKeyword) {
3894 // Use a simple length-based heuristic to determine the minimum possible
3895 // edit distance. If the minimum isn't good enough, bail out early.
3896 StringRef TypoStr = Typo->getName();
3897 unsigned MinED = abs((int)Name.size() - (int)TypoStr.size());
3898 if (MinED && TypoStr.size() / MinED < 3)
3901 // Compute an upper bound on the allowable edit distance, so that the
3902 // edit-distance algorithm can short-circuit.
3903 unsigned UpperBound = (TypoStr.size() + 2) / 3 + 1;
3904 unsigned ED = TypoStr.edit_distance(Name, true, UpperBound);
3905 if (ED >= UpperBound) return;
3907 TypoCorrection TC(&SemaRef.Context.Idents.get(Name), ND, NNS, ED);
3908 if (isKeyword) TC.makeKeyword();
3909 TC.setCorrectionRange(nullptr, Result.getLookupNameInfo());
3913 static const unsigned MaxTypoDistanceResultSets = 5;
3915 void TypoCorrectionConsumer::addCorrection(TypoCorrection Correction) {
3916 StringRef TypoStr = Typo->getName();
3917 StringRef Name = Correction.getCorrectionAsIdentifierInfo()->getName();
3919 // For very short typos, ignore potential corrections that have a different
3920 // base identifier from the typo or which have a normalized edit distance
3921 // longer than the typo itself.
3922 if (TypoStr.size() < 3 &&
3923 (Name != TypoStr || Correction.getEditDistance(true) > TypoStr.size()))
3926 // If the correction is resolved but is not viable, ignore it.
3927 if (Correction.isResolved()) {
3928 checkCorrectionVisibility(SemaRef, Correction);
3929 if (!Correction || !isCandidateViable(*CorrectionValidator, Correction))
3933 TypoResultList &CList =
3934 CorrectionResults[Correction.getEditDistance(false)][Name];
3936 if (!CList.empty() && !CList.back().isResolved())
3938 if (NamedDecl *NewND = Correction.getCorrectionDecl()) {
3939 std::string CorrectionStr = Correction.getAsString(SemaRef.getLangOpts());
3940 for (TypoResultList::iterator RI = CList.begin(), RIEnd = CList.end();
3941 RI != RIEnd; ++RI) {
3942 // If the Correction refers to a decl already in the result list,
3943 // replace the existing result if the string representation of Correction
3944 // comes before the current result alphabetically, then stop as there is
3945 // nothing more to be done to add Correction to the candidate set.
3946 if (RI->getCorrectionDecl() == NewND) {
3947 if (CorrectionStr < RI->getAsString(SemaRef.getLangOpts()))
3953 if (CList.empty() || Correction.isResolved())
3954 CList.push_back(Correction);
3956 while (CorrectionResults.size() > MaxTypoDistanceResultSets)
3957 CorrectionResults.erase(std::prev(CorrectionResults.end()));
3960 void TypoCorrectionConsumer::addNamespaces(
3961 const llvm::MapVector<NamespaceDecl *, bool> &KnownNamespaces) {
3962 SearchNamespaces = true;
3964 for (auto KNPair : KnownNamespaces)
3965 Namespaces.addNameSpecifier(KNPair.first);
3967 bool SSIsTemplate = false;
3968 if (NestedNameSpecifier *NNS =
3969 (SS && SS->isValid()) ? SS->getScopeRep() : nullptr) {
3970 if (const Type *T = NNS->getAsType())
3971 SSIsTemplate = T->getTypeClass() == Type::TemplateSpecialization;
3973 // Do not transform this into an iterator-based loop. The loop body can
3974 // trigger the creation of further types (through lazy deserialization) and
3975 // invalide iterators into this list.
3976 auto &Types = SemaRef.getASTContext().getTypes();
3977 for (unsigned I = 0; I != Types.size(); ++I) {
3978 const auto *TI = Types[I];
3979 if (CXXRecordDecl *CD = TI->getAsCXXRecordDecl()) {
3980 CD = CD->getCanonicalDecl();
3981 if (!CD->isDependentType() && !CD->isAnonymousStructOrUnion() &&
3982 !CD->isUnion() && CD->getIdentifier() &&
3983 (SSIsTemplate || !isa<ClassTemplateSpecializationDecl>(CD)) &&
3984 (CD->isBeingDefined() || CD->isCompleteDefinition()))
3985 Namespaces.addNameSpecifier(CD);
3990 const TypoCorrection &TypoCorrectionConsumer::getNextCorrection() {
3991 if (++CurrentTCIndex < ValidatedCorrections.size())
3992 return ValidatedCorrections[CurrentTCIndex];
3994 CurrentTCIndex = ValidatedCorrections.size();
3995 while (!CorrectionResults.empty()) {
3996 auto DI = CorrectionResults.begin();
3997 if (DI->second.empty()) {
3998 CorrectionResults.erase(DI);
4002 auto RI = DI->second.begin();
4003 if (RI->second.empty()) {
4004 DI->second.erase(RI);
4005 performQualifiedLookups();
4009 TypoCorrection TC = RI->second.pop_back_val();
4010 if (TC.isResolved() || TC.requiresImport() || resolveCorrection(TC)) {
4011 ValidatedCorrections.push_back(TC);
4012 return ValidatedCorrections[CurrentTCIndex];
4015 return ValidatedCorrections[0]; // The empty correction.
4018 bool TypoCorrectionConsumer::resolveCorrection(TypoCorrection &Candidate) {
4019 IdentifierInfo *Name = Candidate.getCorrectionAsIdentifierInfo();
4020 DeclContext *TempMemberContext = MemberContext;
4021 CXXScopeSpec *TempSS = SS.get();
4023 LookupPotentialTypoResult(SemaRef, Result, Name, S, TempSS, TempMemberContext,
4025 CorrectionValidator->IsObjCIvarLookup,
4026 Name == Typo && !Candidate.WillReplaceSpecifier());
4027 switch (Result.getResultKind()) {
4028 case LookupResult::NotFound:
4029 case LookupResult::NotFoundInCurrentInstantiation:
4030 case LookupResult::FoundUnresolvedValue:
4032 // Immediately retry the lookup without the given CXXScopeSpec
4034 Candidate.WillReplaceSpecifier(true);
4037 if (TempMemberContext) {
4040 TempMemberContext = nullptr;
4043 if (SearchNamespaces)
4044 QualifiedResults.push_back(Candidate);
4047 case LookupResult::Ambiguous:
4048 // We don't deal with ambiguities.
4051 case LookupResult::Found:
4052 case LookupResult::FoundOverloaded:
4053 // Store all of the Decls for overloaded symbols
4054 for (auto *TRD : Result)
4055 Candidate.addCorrectionDecl(TRD);
4056 checkCorrectionVisibility(SemaRef, Candidate);
4057 if (!isCandidateViable(*CorrectionValidator, Candidate)) {
4058 if (SearchNamespaces)
4059 QualifiedResults.push_back(Candidate);
4062 Candidate.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
4068 void TypoCorrectionConsumer::performQualifiedLookups() {
4069 unsigned TypoLen = Typo->getName().size();
4070 for (const TypoCorrection &QR : QualifiedResults) {
4071 for (const auto &NSI : Namespaces) {
4072 DeclContext *Ctx = NSI.DeclCtx;
4073 const Type *NSType = NSI.NameSpecifier->getAsType();
4075 // If the current NestedNameSpecifier refers to a class and the
4076 // current correction candidate is the name of that class, then skip
4077 // it as it is unlikely a qualified version of the class' constructor
4078 // is an appropriate correction.
4079 if (CXXRecordDecl *NSDecl = NSType ? NSType->getAsCXXRecordDecl() :
4081 if (NSDecl->getIdentifier() == QR.getCorrectionAsIdentifierInfo())
4085 TypoCorrection TC(QR);
4086 TC.ClearCorrectionDecls();
4087 TC.setCorrectionSpecifier(NSI.NameSpecifier);
4088 TC.setQualifierDistance(NSI.EditDistance);
4089 TC.setCallbackDistance(0); // Reset the callback distance
4091 // If the current correction candidate and namespace combination are
4092 // too far away from the original typo based on the normalized edit
4093 // distance, then skip performing a qualified name lookup.
4094 unsigned TmpED = TC.getEditDistance(true);
4095 if (QR.getCorrectionAsIdentifierInfo() != Typo && TmpED &&
4096 TypoLen / TmpED < 3)
4100 Result.setLookupName(QR.getCorrectionAsIdentifierInfo());
4101 if (!SemaRef.LookupQualifiedName(Result, Ctx))
4104 // Any corrections added below will be validated in subsequent
4105 // iterations of the main while() loop over the Consumer's contents.
4106 switch (Result.getResultKind()) {
4107 case LookupResult::Found:
4108 case LookupResult::FoundOverloaded: {
4109 if (SS && SS->isValid()) {
4110 std::string NewQualified = TC.getAsString(SemaRef.getLangOpts());
4111 std::string OldQualified;
4112 llvm::raw_string_ostream OldOStream(OldQualified);
4113 SS->getScopeRep()->print(OldOStream, SemaRef.getPrintingPolicy());
4114 OldOStream << Typo->getName();
4115 // If correction candidate would be an identical written qualified
4116 // identifer, then the existing CXXScopeSpec probably included a
4117 // typedef that didn't get accounted for properly.
4118 if (OldOStream.str() == NewQualified)
4121 for (LookupResult::iterator TRD = Result.begin(), TRDEnd = Result.end();
4122 TRD != TRDEnd; ++TRD) {
4123 if (SemaRef.CheckMemberAccess(TC.getCorrectionRange().getBegin(),
4124 NSType ? NSType->getAsCXXRecordDecl()
4126 TRD.getPair()) == Sema::AR_accessible)
4127 TC.addCorrectionDecl(*TRD);
4129 if (TC.isResolved()) {
4130 TC.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
4135 case LookupResult::NotFound:
4136 case LookupResult::NotFoundInCurrentInstantiation:
4137 case LookupResult::Ambiguous:
4138 case LookupResult::FoundUnresolvedValue:
4143 QualifiedResults.clear();
4146 TypoCorrectionConsumer::NamespaceSpecifierSet::NamespaceSpecifierSet(
4147 ASTContext &Context, DeclContext *CurContext, CXXScopeSpec *CurScopeSpec)
4148 : Context(Context), CurContextChain(buildContextChain(CurContext)) {
4149 if (NestedNameSpecifier *NNS =
4150 CurScopeSpec ? CurScopeSpec->getScopeRep() : nullptr) {
4151 llvm::raw_string_ostream SpecifierOStream(CurNameSpecifier);
4152 NNS->print(SpecifierOStream, Context.getPrintingPolicy());
4154 getNestedNameSpecifierIdentifiers(NNS, CurNameSpecifierIdentifiers);
4156 // Build the list of identifiers that would be used for an absolute
4157 // (from the global context) NestedNameSpecifier referring to the current
4159 for (DeclContext *C : llvm::reverse(CurContextChain)) {
4160 if (auto *ND = dyn_cast_or_null<NamespaceDecl>(C))
4161 CurContextIdentifiers.push_back(ND->getIdentifier());
4164 // Add the global context as a NestedNameSpecifier
4165 SpecifierInfo SI = {cast<DeclContext>(Context.getTranslationUnitDecl()),
4166 NestedNameSpecifier::GlobalSpecifier(Context), 1};
4167 DistanceMap[1].push_back(SI);
4170 auto TypoCorrectionConsumer::NamespaceSpecifierSet::buildContextChain(
4171 DeclContext *Start) -> DeclContextList {
4172 assert(Start && "Building a context chain from a null context");
4173 DeclContextList Chain;
4174 for (DeclContext *DC = Start->getPrimaryContext(); DC != nullptr;
4175 DC = DC->getLookupParent()) {
4176 NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(DC);
4177 if (!DC->isInlineNamespace() && !DC->isTransparentContext() &&
4178 !(ND && ND->isAnonymousNamespace()))
4179 Chain.push_back(DC->getPrimaryContext());
4185 TypoCorrectionConsumer::NamespaceSpecifierSet::buildNestedNameSpecifier(
4186 DeclContextList &DeclChain, NestedNameSpecifier *&NNS) {
4187 unsigned NumSpecifiers = 0;
4188 for (DeclContext *C : llvm::reverse(DeclChain)) {
4189 if (auto *ND = dyn_cast_or_null<NamespaceDecl>(C)) {
4190 NNS = NestedNameSpecifier::Create(Context, NNS, ND);
4192 } else if (auto *RD = dyn_cast_or_null<RecordDecl>(C)) {
4193 NNS = NestedNameSpecifier::Create(Context, NNS, RD->isTemplateDecl(),
4194 RD->getTypeForDecl());
4198 return NumSpecifiers;
4201 void TypoCorrectionConsumer::NamespaceSpecifierSet::addNameSpecifier(
4203 NestedNameSpecifier *NNS = nullptr;
4204 unsigned NumSpecifiers = 0;
4205 DeclContextList NamespaceDeclChain(buildContextChain(Ctx));
4206 DeclContextList FullNamespaceDeclChain(NamespaceDeclChain);
4208 // Eliminate common elements from the two DeclContext chains.
4209 for (DeclContext *C : llvm::reverse(CurContextChain)) {
4210 if (NamespaceDeclChain.empty() || NamespaceDeclChain.back() != C)
4212 NamespaceDeclChain.pop_back();
4215 // Build the NestedNameSpecifier from what is left of the NamespaceDeclChain
4216 NumSpecifiers = buildNestedNameSpecifier(NamespaceDeclChain, NNS);
4218 // Add an explicit leading '::' specifier if needed.
4219 if (NamespaceDeclChain.empty()) {
4220 // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
4221 NNS = NestedNameSpecifier::GlobalSpecifier(Context);
4223 buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
4224 } else if (NamedDecl *ND =
4225 dyn_cast_or_null<NamedDecl>(NamespaceDeclChain.back())) {
4226 IdentifierInfo *Name = ND->getIdentifier();
4227 bool SameNameSpecifier = false;
4228 if (std::find(CurNameSpecifierIdentifiers.begin(),
4229 CurNameSpecifierIdentifiers.end(),
4230 Name) != CurNameSpecifierIdentifiers.end()) {
4231 std::string NewNameSpecifier;
4232 llvm::raw_string_ostream SpecifierOStream(NewNameSpecifier);
4233 SmallVector<const IdentifierInfo *, 4> NewNameSpecifierIdentifiers;
4234 getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
4235 NNS->print(SpecifierOStream, Context.getPrintingPolicy());
4236 SpecifierOStream.flush();
4237 SameNameSpecifier = NewNameSpecifier == CurNameSpecifier;
4239 if (SameNameSpecifier ||
4240 std::find(CurContextIdentifiers.begin(), CurContextIdentifiers.end(),
4241 Name) != CurContextIdentifiers.end()) {
4242 // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
4243 NNS = NestedNameSpecifier::GlobalSpecifier(Context);
4245 buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
4249 // If the built NestedNameSpecifier would be replacing an existing
4250 // NestedNameSpecifier, use the number of component identifiers that
4251 // would need to be changed as the edit distance instead of the number
4252 // of components in the built NestedNameSpecifier.
4253 if (NNS && !CurNameSpecifierIdentifiers.empty()) {
4254 SmallVector<const IdentifierInfo*, 4> NewNameSpecifierIdentifiers;
4255 getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
4256 NumSpecifiers = llvm::ComputeEditDistance(
4257 llvm::makeArrayRef(CurNameSpecifierIdentifiers),
4258 llvm::makeArrayRef(NewNameSpecifierIdentifiers));
4261 SpecifierInfo SI = {Ctx, NNS, NumSpecifiers};
4262 DistanceMap[NumSpecifiers].push_back(SI);
4265 /// \brief Perform name lookup for a possible result for typo correction.
4266 static void LookupPotentialTypoResult(Sema &SemaRef,
4268 IdentifierInfo *Name,
4269 Scope *S, CXXScopeSpec *SS,
4270 DeclContext *MemberContext,
4271 bool EnteringContext,
4272 bool isObjCIvarLookup,
4274 Res.suppressDiagnostics();
4276 Res.setLookupName(Name);
4277 Res.setAllowHidden(FindHidden);
4278 if (MemberContext) {
4279 if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(MemberContext)) {
4280 if (isObjCIvarLookup) {
4281 if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(Name)) {
4288 if (ObjCPropertyDecl *Prop = Class->FindPropertyDeclaration(
4289 Name, ObjCPropertyQueryKind::OBJC_PR_query_instance)) {
4296 SemaRef.LookupQualifiedName(Res, MemberContext);
4300 SemaRef.LookupParsedName(Res, S, SS, /*AllowBuiltinCreation=*/false,
4303 // Fake ivar lookup; this should really be part of
4304 // LookupParsedName.
4305 if (ObjCMethodDecl *Method = SemaRef.getCurMethodDecl()) {
4306 if (Method->isInstanceMethod() && Method->getClassInterface() &&
4308 (Res.isSingleResult() &&
4309 Res.getFoundDecl()->isDefinedOutsideFunctionOrMethod()))) {
4310 if (ObjCIvarDecl *IV
4311 = Method->getClassInterface()->lookupInstanceVariable(Name)) {
4319 /// \brief Add keywords to the consumer as possible typo corrections.
4320 static void AddKeywordsToConsumer(Sema &SemaRef,
4321 TypoCorrectionConsumer &Consumer,
4322 Scope *S, CorrectionCandidateCallback &CCC,
4323 bool AfterNestedNameSpecifier) {
4324 if (AfterNestedNameSpecifier) {
4325 // For 'X::', we know exactly which keywords can appear next.
4326 Consumer.addKeywordResult("template");
4327 if (CCC.WantExpressionKeywords)
4328 Consumer.addKeywordResult("operator");
4332 if (CCC.WantObjCSuper)
4333 Consumer.addKeywordResult("super");
4335 if (CCC.WantTypeSpecifiers) {
4336 // Add type-specifier keywords to the set of results.
4337 static const char *const CTypeSpecs[] = {
4338 "char", "const", "double", "enum", "float", "int", "long", "short",
4339 "signed", "struct", "union", "unsigned", "void", "volatile",
4340 "_Complex", "_Imaginary",
4341 // storage-specifiers as well
4342 "extern", "inline", "static", "typedef"
4345 const unsigned NumCTypeSpecs = llvm::array_lengthof(CTypeSpecs);
4346 for (unsigned I = 0; I != NumCTypeSpecs; ++I)
4347 Consumer.addKeywordResult(CTypeSpecs[I]);
4349 if (SemaRef.getLangOpts().C99)
4350 Consumer.addKeywordResult("restrict");
4351 if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus)
4352 Consumer.addKeywordResult("bool");
4353 else if (SemaRef.getLangOpts().C99)
4354 Consumer.addKeywordResult("_Bool");
4356 if (SemaRef.getLangOpts().CPlusPlus) {
4357 Consumer.addKeywordResult("class");
4358 Consumer.addKeywordResult("typename");
4359 Consumer.addKeywordResult("wchar_t");
4361 if (SemaRef.getLangOpts().CPlusPlus11) {
4362 Consumer.addKeywordResult("char16_t");
4363 Consumer.addKeywordResult("char32_t");
4364 Consumer.addKeywordResult("constexpr");
4365 Consumer.addKeywordResult("decltype");
4366 Consumer.addKeywordResult("thread_local");
4370 if (SemaRef.getLangOpts().GNUMode)
4371 Consumer.addKeywordResult("typeof");
4372 } else if (CCC.WantFunctionLikeCasts) {
4373 static const char *const CastableTypeSpecs[] = {
4374 "char", "double", "float", "int", "long", "short",
4375 "signed", "unsigned", "void"
4377 for (auto *kw : CastableTypeSpecs)
4378 Consumer.addKeywordResult(kw);
4381 if (CCC.WantCXXNamedCasts && SemaRef.getLangOpts().CPlusPlus) {
4382 Consumer.addKeywordResult("const_cast");
4383 Consumer.addKeywordResult("dynamic_cast");
4384 Consumer.addKeywordResult("reinterpret_cast");
4385 Consumer.addKeywordResult("static_cast");
4388 if (CCC.WantExpressionKeywords) {
4389 Consumer.addKeywordResult("sizeof");
4390 if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus) {
4391 Consumer.addKeywordResult("false");
4392 Consumer.addKeywordResult("true");
4395 if (SemaRef.getLangOpts().CPlusPlus) {
4396 static const char *const CXXExprs[] = {
4397 "delete", "new", "operator", "throw", "typeid"
4399 const unsigned NumCXXExprs = llvm::array_lengthof(CXXExprs);
4400 for (unsigned I = 0; I != NumCXXExprs; ++I)
4401 Consumer.addKeywordResult(CXXExprs[I]);
4403 if (isa<CXXMethodDecl>(SemaRef.CurContext) &&
4404 cast<CXXMethodDecl>(SemaRef.CurContext)->isInstance())
4405 Consumer.addKeywordResult("this");
4407 if (SemaRef.getLangOpts().CPlusPlus11) {
4408 Consumer.addKeywordResult("alignof");
4409 Consumer.addKeywordResult("nullptr");
4413 if (SemaRef.getLangOpts().C11) {
4414 // FIXME: We should not suggest _Alignof if the alignof macro
4416 Consumer.addKeywordResult("_Alignof");
4420 if (CCC.WantRemainingKeywords) {
4421 if (SemaRef.getCurFunctionOrMethodDecl() || SemaRef.getCurBlock()) {
4423 static const char *const CStmts[] = {
4424 "do", "else", "for", "goto", "if", "return", "switch", "while" };
4425 const unsigned NumCStmts = llvm::array_lengthof(CStmts);
4426 for (unsigned I = 0; I != NumCStmts; ++I)
4427 Consumer.addKeywordResult(CStmts[I]);
4429 if (SemaRef.getLangOpts().CPlusPlus) {
4430 Consumer.addKeywordResult("catch");
4431 Consumer.addKeywordResult("try");
4434 if (S && S->getBreakParent())
4435 Consumer.addKeywordResult("break");
4437 if (S && S->getContinueParent())
4438 Consumer.addKeywordResult("continue");
4440 if (!SemaRef.getCurFunction()->SwitchStack.empty()) {
4441 Consumer.addKeywordResult("case");
4442 Consumer.addKeywordResult("default");
4445 if (SemaRef.getLangOpts().CPlusPlus) {
4446 Consumer.addKeywordResult("namespace");
4447 Consumer.addKeywordResult("template");
4450 if (S && S->isClassScope()) {
4451 Consumer.addKeywordResult("explicit");
4452 Consumer.addKeywordResult("friend");
4453 Consumer.addKeywordResult("mutable");
4454 Consumer.addKeywordResult("private");
4455 Consumer.addKeywordResult("protected");
4456 Consumer.addKeywordResult("public");
4457 Consumer.addKeywordResult("virtual");
4461 if (SemaRef.getLangOpts().CPlusPlus) {
4462 Consumer.addKeywordResult("using");
4464 if (SemaRef.getLangOpts().CPlusPlus11)
4465 Consumer.addKeywordResult("static_assert");
4470 std::unique_ptr<TypoCorrectionConsumer> Sema::makeTypoCorrectionConsumer(
4471 const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
4472 Scope *S, CXXScopeSpec *SS,
4473 std::unique_ptr<CorrectionCandidateCallback> CCC,
4474 DeclContext *MemberContext, bool EnteringContext,
4475 const ObjCObjectPointerType *OPT, bool ErrorRecovery) {
4477 if (Diags.hasFatalErrorOccurred() || !getLangOpts().SpellChecking ||
4478 DisableTypoCorrection)
4481 // In Microsoft mode, don't perform typo correction in a template member
4482 // function dependent context because it interferes with the "lookup into
4483 // dependent bases of class templates" feature.
4484 if (getLangOpts().MSVCCompat && CurContext->isDependentContext() &&
4485 isa<CXXMethodDecl>(CurContext))
4488 // We only attempt to correct typos for identifiers.
4489 IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4493 // If the scope specifier itself was invalid, don't try to correct
4495 if (SS && SS->isInvalid())
4498 // Never try to correct typos during template deduction or
4500 if (!ActiveTemplateInstantiations.empty())
4503 // Don't try to correct 'super'.
4504 if (S && S->isInObjcMethodScope() && Typo == getSuperIdentifier())
4507 // Abort if typo correction already failed for this specific typo.
4508 IdentifierSourceLocations::iterator locs = TypoCorrectionFailures.find(Typo);
4509 if (locs != TypoCorrectionFailures.end() &&
4510 locs->second.count(TypoName.getLoc()))
4513 // Don't try to correct the identifier "vector" when in AltiVec mode.
4514 // TODO: Figure out why typo correction misbehaves in this case, fix it, and
4515 // remove this workaround.
4516 if ((getLangOpts().AltiVec || getLangOpts().ZVector) && Typo->isStr("vector"))
4519 // Provide a stop gap for files that are just seriously broken. Trying
4520 // to correct all typos can turn into a HUGE performance penalty, causing
4521 // some files to take minutes to get rejected by the parser.
4522 unsigned Limit = getDiagnostics().getDiagnosticOptions().SpellCheckingLimit;
4523 if (Limit && TyposCorrected >= Limit)
4527 // If we're handling a missing symbol error, using modules, and the
4528 // special search all modules option is used, look for a missing import.
4529 if (ErrorRecovery && getLangOpts().Modules &&
4530 getLangOpts().ModulesSearchAll) {
4531 // The following has the side effect of loading the missing module.
4532 getModuleLoader().lookupMissingImports(Typo->getName(),
4533 TypoName.getLocStart());
4536 CorrectionCandidateCallback &CCCRef = *CCC;
4537 auto Consumer = llvm::make_unique<TypoCorrectionConsumer>(
4538 *this, TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4541 // Perform name lookup to find visible, similarly-named entities.
4542 bool IsUnqualifiedLookup = false;
4543 DeclContext *QualifiedDC = MemberContext;
4544 if (MemberContext) {
4545 LookupVisibleDecls(MemberContext, LookupKind, *Consumer);
4547 // Look in qualified interfaces.
4549 for (auto *I : OPT->quals())
4550 LookupVisibleDecls(I, LookupKind, *Consumer);
4552 } else if (SS && SS->isSet()) {
4553 QualifiedDC = computeDeclContext(*SS, EnteringContext);
4557 LookupVisibleDecls(QualifiedDC, LookupKind, *Consumer);
4559 IsUnqualifiedLookup = true;
4562 // Determine whether we are going to search in the various namespaces for
4564 bool SearchNamespaces
4565 = getLangOpts().CPlusPlus &&
4566 (IsUnqualifiedLookup || (SS && SS->isSet()));
4568 if (IsUnqualifiedLookup || SearchNamespaces) {
4569 // For unqualified lookup, look through all of the names that we have
4570 // seen in this translation unit.
4571 // FIXME: Re-add the ability to skip very unlikely potential corrections.
4572 for (const auto &I : Context.Idents)
4573 Consumer->FoundName(I.getKey());
4575 // Walk through identifiers in external identifier sources.
4576 // FIXME: Re-add the ability to skip very unlikely potential corrections.
4577 if (IdentifierInfoLookup *External
4578 = Context.Idents.getExternalIdentifierLookup()) {
4579 std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
4581 StringRef Name = Iter->Next();
4585 Consumer->FoundName(Name);
4590 AddKeywordsToConsumer(*this, *Consumer, S, CCCRef, SS && SS->isNotEmpty());
4592 // Build the NestedNameSpecifiers for the KnownNamespaces, if we're going
4593 // to search those namespaces.
4594 if (SearchNamespaces) {
4595 // Load any externally-known namespaces.
4596 if (ExternalSource && !LoadedExternalKnownNamespaces) {
4597 SmallVector<NamespaceDecl *, 4> ExternalKnownNamespaces;
4598 LoadedExternalKnownNamespaces = true;
4599 ExternalSource->ReadKnownNamespaces(ExternalKnownNamespaces);
4600 for (auto *N : ExternalKnownNamespaces)
4601 KnownNamespaces[N] = true;
4604 Consumer->addNamespaces(KnownNamespaces);
4610 /// \brief Try to "correct" a typo in the source code by finding
4611 /// visible declarations whose names are similar to the name that was
4612 /// present in the source code.
4614 /// \param TypoName the \c DeclarationNameInfo structure that contains
4615 /// the name that was present in the source code along with its location.
4617 /// \param LookupKind the name-lookup criteria used to search for the name.
4619 /// \param S the scope in which name lookup occurs.
4621 /// \param SS the nested-name-specifier that precedes the name we're
4622 /// looking for, if present.
4624 /// \param CCC A CorrectionCandidateCallback object that provides further
4625 /// validation of typo correction candidates. It also provides flags for
4626 /// determining the set of keywords permitted.
4628 /// \param MemberContext if non-NULL, the context in which to look for
4629 /// a member access expression.
4631 /// \param EnteringContext whether we're entering the context described by
4632 /// the nested-name-specifier SS.
4634 /// \param OPT when non-NULL, the search for visible declarations will
4635 /// also walk the protocols in the qualified interfaces of \p OPT.
4637 /// \returns a \c TypoCorrection containing the corrected name if the typo
4638 /// along with information such as the \c NamedDecl where the corrected name
4639 /// was declared, and any additional \c NestedNameSpecifier needed to access
4640 /// it (C++ only). The \c TypoCorrection is empty if there is no correction.
4641 TypoCorrection Sema::CorrectTypo(const DeclarationNameInfo &TypoName,
4642 Sema::LookupNameKind LookupKind,
4643 Scope *S, CXXScopeSpec *SS,
4644 std::unique_ptr<CorrectionCandidateCallback> CCC,
4645 CorrectTypoKind Mode,
4646 DeclContext *MemberContext,
4647 bool EnteringContext,
4648 const ObjCObjectPointerType *OPT,
4649 bool RecordFailure) {
4650 assert(CCC && "CorrectTypo requires a CorrectionCandidateCallback");
4652 // Always let the ExternalSource have the first chance at correction, even
4653 // if we would otherwise have given up.
4654 if (ExternalSource) {
4655 if (TypoCorrection Correction = ExternalSource->CorrectTypo(
4656 TypoName, LookupKind, S, SS, *CCC, MemberContext, EnteringContext, OPT))
4660 // Ugly hack equivalent to CTC == CTC_ObjCMessageReceiver;
4661 // WantObjCSuper is only true for CTC_ObjCMessageReceiver and for
4662 // some instances of CTC_Unknown, while WantRemainingKeywords is true
4663 // for CTC_Unknown but not for CTC_ObjCMessageReceiver.
4664 bool ObjCMessageReceiver = CCC->WantObjCSuper && !CCC->WantRemainingKeywords;
4666 IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4667 auto Consumer = makeTypoCorrectionConsumer(
4668 TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4669 EnteringContext, OPT, Mode == CTK_ErrorRecovery);
4672 return TypoCorrection();
4674 // If we haven't found anything, we're done.
4675 if (Consumer->empty())
4676 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4678 // Make sure the best edit distance (prior to adding any namespace qualifiers)
4679 // is not more that about a third of the length of the typo's identifier.
4680 unsigned ED = Consumer->getBestEditDistance(true);
4681 unsigned TypoLen = Typo->getName().size();
4682 if (ED > 0 && TypoLen / ED < 3)
4683 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4685 TypoCorrection BestTC = Consumer->getNextCorrection();
4686 TypoCorrection SecondBestTC = Consumer->getNextCorrection();
4688 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4690 ED = BestTC.getEditDistance();
4692 if (TypoLen >= 3 && ED > 0 && TypoLen / ED < 3) {
4693 // If this was an unqualified lookup and we believe the callback
4694 // object wouldn't have filtered out possible corrections, note
4695 // that no correction was found.
4696 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4699 // If only a single name remains, return that result.
4700 if (!SecondBestTC ||
4701 SecondBestTC.getEditDistance(false) > BestTC.getEditDistance(false)) {
4702 const TypoCorrection &Result = BestTC;
4704 // Don't correct to a keyword that's the same as the typo; the keyword
4705 // wasn't actually in scope.
4706 if (ED == 0 && Result.isKeyword())
4707 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4709 TypoCorrection TC = Result;
4710 TC.setCorrectionRange(SS, TypoName);
4711 checkCorrectionVisibility(*this, TC);
4713 } else if (SecondBestTC && ObjCMessageReceiver) {
4714 // Prefer 'super' when we're completing in a message-receiver
4717 if (BestTC.getCorrection().getAsString() != "super") {
4718 if (SecondBestTC.getCorrection().getAsString() == "super")
4719 BestTC = SecondBestTC;
4720 else if ((*Consumer)["super"].front().isKeyword())
4721 BestTC = (*Consumer)["super"].front();
4723 // Don't correct to a keyword that's the same as the typo; the keyword
4724 // wasn't actually in scope.
4725 if (BestTC.getEditDistance() == 0 ||
4726 BestTC.getCorrection().getAsString() != "super")
4727 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4729 BestTC.setCorrectionRange(SS, TypoName);
4733 // Record the failure's location if needed and return an empty correction. If
4734 // this was an unqualified lookup and we believe the callback object did not
4735 // filter out possible corrections, also cache the failure for the typo.
4736 return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure && !SecondBestTC);
4739 /// \brief Try to "correct" a typo in the source code by finding
4740 /// visible declarations whose names are similar to the name that was
4741 /// present in the source code.
4743 /// \param TypoName the \c DeclarationNameInfo structure that contains
4744 /// the name that was present in the source code along with its location.
4746 /// \param LookupKind the name-lookup criteria used to search for the name.
4748 /// \param S the scope in which name lookup occurs.
4750 /// \param SS the nested-name-specifier that precedes the name we're
4751 /// looking for, if present.
4753 /// \param CCC A CorrectionCandidateCallback object that provides further
4754 /// validation of typo correction candidates. It also provides flags for
4755 /// determining the set of keywords permitted.
4757 /// \param TDG A TypoDiagnosticGenerator functor that will be used to print
4758 /// diagnostics when the actual typo correction is attempted.
4760 /// \param TRC A TypoRecoveryCallback functor that will be used to build an
4761 /// Expr from a typo correction candidate.
4763 /// \param MemberContext if non-NULL, the context in which to look for
4764 /// a member access expression.
4766 /// \param EnteringContext whether we're entering the context described by
4767 /// the nested-name-specifier SS.
4769 /// \param OPT when non-NULL, the search for visible declarations will
4770 /// also walk the protocols in the qualified interfaces of \p OPT.
4772 /// \returns a new \c TypoExpr that will later be replaced in the AST with an
4773 /// Expr representing the result of performing typo correction, or nullptr if
4774 /// typo correction is not possible. If nullptr is returned, no diagnostics will
4775 /// be emitted and it is the responsibility of the caller to emit any that are
4777 TypoExpr *Sema::CorrectTypoDelayed(
4778 const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
4779 Scope *S, CXXScopeSpec *SS,
4780 std::unique_ptr<CorrectionCandidateCallback> CCC,
4781 TypoDiagnosticGenerator TDG, TypoRecoveryCallback TRC, CorrectTypoKind Mode,
4782 DeclContext *MemberContext, bool EnteringContext,
4783 const ObjCObjectPointerType *OPT) {
4784 assert(CCC && "CorrectTypoDelayed requires a CorrectionCandidateCallback");
4786 auto Consumer = makeTypoCorrectionConsumer(
4787 TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4788 EnteringContext, OPT, Mode == CTK_ErrorRecovery);
4790 // Give the external sema source a chance to correct the typo.
4791 TypoCorrection ExternalTypo;
4792 if (ExternalSource && Consumer) {
4793 ExternalTypo = ExternalSource->CorrectTypo(
4794 TypoName, LookupKind, S, SS, *Consumer->getCorrectionValidator(),
4795 MemberContext, EnteringContext, OPT);
4797 Consumer->addCorrection(ExternalTypo);
4800 if (!Consumer || Consumer->empty())
4803 // Make sure the best edit distance (prior to adding any namespace qualifiers)
4804 // is not more that about a third of the length of the typo's identifier.
4805 unsigned ED = Consumer->getBestEditDistance(true);
4806 IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4807 if (!ExternalTypo && ED > 0 && Typo->getName().size() / ED < 3)
4810 ExprEvalContexts.back().NumTypos++;
4811 return createDelayedTypo(std::move(Consumer), std::move(TDG), std::move(TRC));
4814 void TypoCorrection::addCorrectionDecl(NamedDecl *CDecl) {
4818 CorrectionDecls.clear();
4820 CorrectionDecls.push_back(CDecl);
4822 if (!CorrectionName)
4823 CorrectionName = CDecl->getDeclName();
4826 std::string TypoCorrection::getAsString(const LangOptions &LO) const {
4827 if (CorrectionNameSpec) {
4828 std::string tmpBuffer;
4829 llvm::raw_string_ostream PrefixOStream(tmpBuffer);
4830 CorrectionNameSpec->print(PrefixOStream, PrintingPolicy(LO));
4831 PrefixOStream << CorrectionName;
4832 return PrefixOStream.str();
4835 return CorrectionName.getAsString();
4838 bool CorrectionCandidateCallback::ValidateCandidate(
4839 const TypoCorrection &candidate) {
4840 if (!candidate.isResolved())
4843 if (candidate.isKeyword())
4844 return WantTypeSpecifiers || WantExpressionKeywords || WantCXXNamedCasts ||
4845 WantRemainingKeywords || WantObjCSuper;
4847 bool HasNonType = false;
4848 bool HasStaticMethod = false;
4849 bool HasNonStaticMethod = false;
4850 for (Decl *D : candidate) {
4851 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(D))
4852 D = FTD->getTemplatedDecl();
4853 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
4854 if (Method->isStatic())
4855 HasStaticMethod = true;
4857 HasNonStaticMethod = true;
4859 if (!isa<TypeDecl>(D))
4863 if (IsAddressOfOperand && HasNonStaticMethod && !HasStaticMethod &&
4864 !candidate.getCorrectionSpecifier())
4867 return WantTypeSpecifiers || HasNonType;
4870 FunctionCallFilterCCC::FunctionCallFilterCCC(Sema &SemaRef, unsigned NumArgs,
4871 bool HasExplicitTemplateArgs,
4873 : NumArgs(NumArgs), HasExplicitTemplateArgs(HasExplicitTemplateArgs),
4874 CurContext(SemaRef.CurContext), MemberFn(ME) {
4875 WantTypeSpecifiers = false;
4876 WantFunctionLikeCasts = SemaRef.getLangOpts().CPlusPlus && NumArgs == 1;
4877 WantRemainingKeywords = false;
4880 bool FunctionCallFilterCCC::ValidateCandidate(const TypoCorrection &candidate) {
4881 if (!candidate.getCorrectionDecl())
4882 return candidate.isKeyword();
4884 for (auto *C : candidate) {
4885 FunctionDecl *FD = nullptr;
4886 NamedDecl *ND = C->getUnderlyingDecl();
4887 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
4888 FD = FTD->getTemplatedDecl();
4889 if (!HasExplicitTemplateArgs && !FD) {
4890 if (!(FD = dyn_cast<FunctionDecl>(ND)) && isa<ValueDecl>(ND)) {
4891 // If the Decl is neither a function nor a template function,
4892 // determine if it is a pointer or reference to a function. If so,
4893 // check against the number of arguments expected for the pointee.
4894 QualType ValType = cast<ValueDecl>(ND)->getType();
4895 if (ValType->isAnyPointerType() || ValType->isReferenceType())
4896 ValType = ValType->getPointeeType();
4897 if (const FunctionProtoType *FPT = ValType->getAs<FunctionProtoType>())
4898 if (FPT->getNumParams() == NumArgs)
4903 // Skip the current candidate if it is not a FunctionDecl or does not accept
4904 // the current number of arguments.
4905 if (!FD || !(FD->getNumParams() >= NumArgs &&
4906 FD->getMinRequiredArguments() <= NumArgs))
4909 // If the current candidate is a non-static C++ method, skip the candidate
4910 // unless the method being corrected--or the current DeclContext, if the
4911 // function being corrected is not a method--is a method in the same class
4912 // or a descendent class of the candidate's parent class.
4913 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
4914 if (MemberFn || !MD->isStatic()) {
4915 CXXMethodDecl *CurMD =
4917 ? dyn_cast_or_null<CXXMethodDecl>(MemberFn->getMemberDecl())
4918 : dyn_cast_or_null<CXXMethodDecl>(CurContext);
4919 CXXRecordDecl *CurRD =
4920 CurMD ? CurMD->getParent()->getCanonicalDecl() : nullptr;
4921 CXXRecordDecl *RD = MD->getParent()->getCanonicalDecl();
4922 if (!CurRD || (CurRD != RD && !CurRD->isDerivedFrom(RD)))
4931 void Sema::diagnoseTypo(const TypoCorrection &Correction,
4932 const PartialDiagnostic &TypoDiag,
4933 bool ErrorRecovery) {
4934 diagnoseTypo(Correction, TypoDiag, PDiag(diag::note_previous_decl),
4938 /// Find which declaration we should import to provide the definition of
4939 /// the given declaration.
4940 static NamedDecl *getDefinitionToImport(NamedDecl *D) {
4941 if (VarDecl *VD = dyn_cast<VarDecl>(D))
4942 return VD->getDefinition();
4943 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
4944 return FD->getDefinition();
4945 if (TagDecl *TD = dyn_cast<TagDecl>(D))
4946 return TD->getDefinition();
4947 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(D))
4948 return ID->getDefinition();
4949 if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl>(D))
4950 return PD->getDefinition();
4951 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
4952 return getDefinitionToImport(TD->getTemplatedDecl());
4956 void Sema::diagnoseMissingImport(SourceLocation Loc, NamedDecl *Decl,
4957 MissingImportKind MIK, bool Recover) {
4958 assert(!isVisible(Decl) && "missing import for non-hidden decl?");
4960 // Suggest importing a module providing the definition of this entity, if
4962 NamedDecl *Def = getDefinitionToImport(Decl);
4966 Module *Owner = getOwningModule(Decl);
4967 assert(Owner && "definition of hidden declaration is not in a module");
4969 llvm::SmallVector<Module*, 8> OwningModules;
4970 OwningModules.push_back(Owner);
4971 auto Merged = Context.getModulesWithMergedDefinition(Decl);
4972 OwningModules.insert(OwningModules.end(), Merged.begin(), Merged.end());
4974 diagnoseMissingImport(Loc, Decl, Decl->getLocation(), OwningModules, MIK,
4978 /// \brief Get a "quoted.h" or <angled.h> include path to use in a diagnostic
4979 /// suggesting the addition of a #include of the specified file.
4980 static std::string getIncludeStringForHeader(Preprocessor &PP,
4981 const FileEntry *E) {
4984 PP.getHeaderSearchInfo().suggestPathToFileForDiagnostics(E, &IsSystem);
4985 return (IsSystem ? '<' : '"') + Path + (IsSystem ? '>' : '"');
4988 void Sema::diagnoseMissingImport(SourceLocation UseLoc, NamedDecl *Decl,
4989 SourceLocation DeclLoc,
4990 ArrayRef<Module *> Modules,
4991 MissingImportKind MIK, bool Recover) {
4992 assert(!Modules.empty());
4994 if (Modules.size() > 1) {
4995 std::string ModuleList;
4997 for (Module *M : Modules) {
4998 ModuleList += "\n ";
4999 if (++N == 5 && N != Modules.size()) {
5000 ModuleList += "[...]";
5003 ModuleList += M->getFullModuleName();
5006 Diag(UseLoc, diag::err_module_unimported_use_multiple)
5007 << (int)MIK << Decl << ModuleList;
5008 } else if (const FileEntry *E =
5009 PP.getModuleHeaderToIncludeForDiagnostics(UseLoc, DeclLoc)) {
5010 // The right way to make the declaration visible is to include a header;
5011 // suggest doing so.
5013 // FIXME: Find a smart place to suggest inserting a #include, and add
5014 // a FixItHint there.
5015 Diag(UseLoc, diag::err_module_unimported_use_header)
5016 << (int)MIK << Decl << Modules[0]->getFullModuleName()
5017 << getIncludeStringForHeader(PP, E);
5019 // FIXME: Add a FixItHint that imports the corresponding module.
5020 Diag(UseLoc, diag::err_module_unimported_use)
5021 << (int)MIK << Decl << Modules[0]->getFullModuleName();
5026 case MissingImportKind::Declaration:
5027 DiagID = diag::note_previous_declaration;
5029 case MissingImportKind::Definition:
5030 DiagID = diag::note_previous_definition;
5032 case MissingImportKind::DefaultArgument:
5033 DiagID = diag::note_default_argument_declared_here;
5035 case MissingImportKind::ExplicitSpecialization:
5036 DiagID = diag::note_explicit_specialization_declared_here;
5038 case MissingImportKind::PartialSpecialization:
5039 DiagID = diag::note_partial_specialization_declared_here;
5042 Diag(DeclLoc, DiagID);
5044 // Try to recover by implicitly importing this module.
5046 createImplicitModuleImportForErrorRecovery(UseLoc, Modules[0]);
5049 /// \brief Diagnose a successfully-corrected typo. Separated from the correction
5050 /// itself to allow external validation of the result, etc.
5052 /// \param Correction The result of performing typo correction.
5053 /// \param TypoDiag The diagnostic to produce. This will have the corrected
5054 /// string added to it (and usually also a fixit).
5055 /// \param PrevNote A note to use when indicating the location of the entity to
5056 /// which we are correcting. Will have the correction string added to it.
5057 /// \param ErrorRecovery If \c true (the default), the caller is going to
5058 /// recover from the typo as if the corrected string had been typed.
5059 /// In this case, \c PDiag must be an error, and we will attach a fixit
5061 void Sema::diagnoseTypo(const TypoCorrection &Correction,
5062 const PartialDiagnostic &TypoDiag,
5063 const PartialDiagnostic &PrevNote,
5064 bool ErrorRecovery) {
5065 std::string CorrectedStr = Correction.getAsString(getLangOpts());
5066 std::string CorrectedQuotedStr = Correction.getQuoted(getLangOpts());
5067 FixItHint FixTypo = FixItHint::CreateReplacement(
5068 Correction.getCorrectionRange(), CorrectedStr);
5070 // Maybe we're just missing a module import.
5071 if (Correction.requiresImport()) {
5072 NamedDecl *Decl = Correction.getFoundDecl();
5073 assert(Decl && "import required but no declaration to import");
5075 diagnoseMissingImport(Correction.getCorrectionRange().getBegin(), Decl,
5076 MissingImportKind::Declaration, ErrorRecovery);
5080 Diag(Correction.getCorrectionRange().getBegin(), TypoDiag)
5081 << CorrectedQuotedStr << (ErrorRecovery ? FixTypo : FixItHint());
5083 NamedDecl *ChosenDecl =
5084 Correction.isKeyword() ? nullptr : Correction.getFoundDecl();
5085 if (PrevNote.getDiagID() && ChosenDecl)
5086 Diag(ChosenDecl->getLocation(), PrevNote)
5087 << CorrectedQuotedStr << (ErrorRecovery ? FixItHint() : FixTypo);
5089 // Add any extra diagnostics.
5090 for (const PartialDiagnostic &PD : Correction.getExtraDiagnostics())
5091 Diag(Correction.getCorrectionRange().getBegin(), PD);
5094 TypoExpr *Sema::createDelayedTypo(std::unique_ptr<TypoCorrectionConsumer> TCC,
5095 TypoDiagnosticGenerator TDG,
5096 TypoRecoveryCallback TRC) {
5097 assert(TCC && "createDelayedTypo requires a valid TypoCorrectionConsumer");
5098 auto TE = new (Context) TypoExpr(Context.DependentTy);
5099 auto &State = DelayedTypos[TE];
5100 State.Consumer = std::move(TCC);
5101 State.DiagHandler = std::move(TDG);
5102 State.RecoveryHandler = std::move(TRC);
5106 const Sema::TypoExprState &Sema::getTypoExprState(TypoExpr *TE) const {
5107 auto Entry = DelayedTypos.find(TE);
5108 assert(Entry != DelayedTypos.end() &&
5109 "Failed to get the state for a TypoExpr!");
5110 return Entry->second;
5113 void Sema::clearDelayedTypo(TypoExpr *TE) {
5114 DelayedTypos.erase(TE);
5117 void Sema::ActOnPragmaDump(Scope *S, SourceLocation IILoc, IdentifierInfo *II) {
5118 DeclarationNameInfo Name(II, IILoc);
5119 LookupResult R(*this, Name, LookupAnyName, Sema::NotForRedeclaration);
5120 R.suppressDiagnostics();
5121 R.setHideTags(false);