1 //===--- SemaCXXScopeSpec.cpp - Semantic Analysis for C++ scope specifiers-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements C++ semantic analysis for scope specifiers.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "TypeLocBuilder.h"
14 #include "clang/AST/ASTContext.h"
15 #include "clang/AST/DeclTemplate.h"
16 #include "clang/AST/ExprCXX.h"
17 #include "clang/AST/NestedNameSpecifier.h"
18 #include "clang/Basic/PartialDiagnostic.h"
19 #include "clang/Sema/DeclSpec.h"
20 #include "clang/Sema/Lookup.h"
21 #include "clang/Sema/SemaInternal.h"
22 #include "clang/Sema/Template.h"
23 #include "llvm/ADT/STLExtras.h"
24 using namespace clang;
25
26 /// Find the current instantiation that associated with the given type.
getCurrentInstantiationOf(QualType T,DeclContext * CurContext)27 static CXXRecordDecl *getCurrentInstantiationOf(QualType T,
28 DeclContext *CurContext) {
29 if (T.isNull())
30 return nullptr;
31
32 const Type *Ty = T->getCanonicalTypeInternal().getTypePtr();
33 if (const RecordType *RecordTy = dyn_cast<RecordType>(Ty)) {
34 CXXRecordDecl *Record = cast<CXXRecordDecl>(RecordTy->getDecl());
35 if (!Record->isDependentContext() ||
36 Record->isCurrentInstantiation(CurContext))
37 return Record;
38
39 return nullptr;
40 } else if (isa<InjectedClassNameType>(Ty))
41 return cast<InjectedClassNameType>(Ty)->getDecl();
42 else
43 return nullptr;
44 }
45
46 /// Compute the DeclContext that is associated with the given type.
47 ///
48 /// \param T the type for which we are attempting to find a DeclContext.
49 ///
50 /// \returns the declaration context represented by the type T,
51 /// or NULL if the declaration context cannot be computed (e.g., because it is
52 /// dependent and not the current instantiation).
computeDeclContext(QualType T)53 DeclContext *Sema::computeDeclContext(QualType T) {
54 if (!T->isDependentType())
55 if (const TagType *Tag = T->getAs<TagType>())
56 return Tag->getDecl();
57
58 return ::getCurrentInstantiationOf(T, CurContext);
59 }
60
61 /// Compute the DeclContext that is associated with the given
62 /// scope specifier.
63 ///
64 /// \param SS the C++ scope specifier as it appears in the source
65 ///
66 /// \param EnteringContext when true, we will be entering the context of
67 /// this scope specifier, so we can retrieve the declaration context of a
68 /// class template or class template partial specialization even if it is
69 /// not the current instantiation.
70 ///
71 /// \returns the declaration context represented by the scope specifier @p SS,
72 /// or NULL if the declaration context cannot be computed (e.g., because it is
73 /// dependent and not the current instantiation).
computeDeclContext(const CXXScopeSpec & SS,bool EnteringContext)74 DeclContext *Sema::computeDeclContext(const CXXScopeSpec &SS,
75 bool EnteringContext) {
76 if (!SS.isSet() || SS.isInvalid())
77 return nullptr;
78
79 NestedNameSpecifier *NNS = SS.getScopeRep();
80 if (NNS->isDependent()) {
81 // If this nested-name-specifier refers to the current
82 // instantiation, return its DeclContext.
83 if (CXXRecordDecl *Record = getCurrentInstantiationOf(NNS))
84 return Record;
85
86 if (EnteringContext) {
87 const Type *NNSType = NNS->getAsType();
88 if (!NNSType) {
89 return nullptr;
90 }
91
92 // Look through type alias templates, per C++0x [temp.dep.type]p1.
93 NNSType = Context.getCanonicalType(NNSType);
94 if (const TemplateSpecializationType *SpecType
95 = NNSType->getAs<TemplateSpecializationType>()) {
96 // We are entering the context of the nested name specifier, so try to
97 // match the nested name specifier to either a primary class template
98 // or a class template partial specialization.
99 if (ClassTemplateDecl *ClassTemplate
100 = dyn_cast_or_null<ClassTemplateDecl>(
101 SpecType->getTemplateName().getAsTemplateDecl())) {
102 QualType ContextType
103 = Context.getCanonicalType(QualType(SpecType, 0));
104
105 // If the type of the nested name specifier is the same as the
106 // injected class name of the named class template, we're entering
107 // into that class template definition.
108 QualType Injected
109 = ClassTemplate->getInjectedClassNameSpecialization();
110 if (Context.hasSameType(Injected, ContextType))
111 return ClassTemplate->getTemplatedDecl();
112
113 // If the type of the nested name specifier is the same as the
114 // type of one of the class template's class template partial
115 // specializations, we're entering into the definition of that
116 // class template partial specialization.
117 if (ClassTemplatePartialSpecializationDecl *PartialSpec
118 = ClassTemplate->findPartialSpecialization(ContextType)) {
119 // A declaration of the partial specialization must be visible.
120 // We can always recover here, because this only happens when we're
121 // entering the context, and that can't happen in a SFINAE context.
122 assert(!isSFINAEContext() &&
123 "partial specialization scope specifier in SFINAE context?");
124 if (!hasVisibleDeclaration(PartialSpec))
125 diagnoseMissingImport(SS.getLastQualifierNameLoc(), PartialSpec,
126 MissingImportKind::PartialSpecialization,
127 /*Recover*/true);
128 return PartialSpec;
129 }
130 }
131 } else if (const RecordType *RecordT = NNSType->getAs<RecordType>()) {
132 // The nested name specifier refers to a member of a class template.
133 return RecordT->getDecl();
134 }
135 }
136
137 return nullptr;
138 }
139
140 switch (NNS->getKind()) {
141 case NestedNameSpecifier::Identifier:
142 llvm_unreachable("Dependent nested-name-specifier has no DeclContext");
143
144 case NestedNameSpecifier::Namespace:
145 return NNS->getAsNamespace();
146
147 case NestedNameSpecifier::NamespaceAlias:
148 return NNS->getAsNamespaceAlias()->getNamespace();
149
150 case NestedNameSpecifier::TypeSpec:
151 case NestedNameSpecifier::TypeSpecWithTemplate: {
152 const TagType *Tag = NNS->getAsType()->getAs<TagType>();
153 assert(Tag && "Non-tag type in nested-name-specifier");
154 return Tag->getDecl();
155 }
156
157 case NestedNameSpecifier::Global:
158 return Context.getTranslationUnitDecl();
159
160 case NestedNameSpecifier::Super:
161 return NNS->getAsRecordDecl();
162 }
163
164 llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
165 }
166
isDependentScopeSpecifier(const CXXScopeSpec & SS)167 bool Sema::isDependentScopeSpecifier(const CXXScopeSpec &SS) {
168 if (!SS.isSet() || SS.isInvalid())
169 return false;
170
171 return SS.getScopeRep()->isDependent();
172 }
173
174 /// If the given nested name specifier refers to the current
175 /// instantiation, return the declaration that corresponds to that
176 /// current instantiation (C++0x [temp.dep.type]p1).
177 ///
178 /// \param NNS a dependent nested name specifier.
getCurrentInstantiationOf(NestedNameSpecifier * NNS)179 CXXRecordDecl *Sema::getCurrentInstantiationOf(NestedNameSpecifier *NNS) {
180 assert(getLangOpts().CPlusPlus && "Only callable in C++");
181 assert(NNS->isDependent() && "Only dependent nested-name-specifier allowed");
182
183 if (!NNS->getAsType())
184 return nullptr;
185
186 QualType T = QualType(NNS->getAsType(), 0);
187 return ::getCurrentInstantiationOf(T, CurContext);
188 }
189
190 /// Require that the context specified by SS be complete.
191 ///
192 /// If SS refers to a type, this routine checks whether the type is
193 /// complete enough (or can be made complete enough) for name lookup
194 /// into the DeclContext. A type that is not yet completed can be
195 /// considered "complete enough" if it is a class/struct/union/enum
196 /// that is currently being defined. Or, if we have a type that names
197 /// a class template specialization that is not a complete type, we
198 /// will attempt to instantiate that class template.
RequireCompleteDeclContext(CXXScopeSpec & SS,DeclContext * DC)199 bool Sema::RequireCompleteDeclContext(CXXScopeSpec &SS,
200 DeclContext *DC) {
201 assert(DC && "given null context");
202
203 TagDecl *tag = dyn_cast<TagDecl>(DC);
204
205 // If this is a dependent type, then we consider it complete.
206 // FIXME: This is wrong; we should require a (visible) definition to
207 // exist in this case too.
208 if (!tag || tag->isDependentContext())
209 return false;
210
211 // Grab the tag definition, if there is one.
212 QualType type = Context.getTypeDeclType(tag);
213 tag = type->getAsTagDecl();
214
215 // If we're currently defining this type, then lookup into the
216 // type is okay: don't complain that it isn't complete yet.
217 if (tag->isBeingDefined())
218 return false;
219
220 SourceLocation loc = SS.getLastQualifierNameLoc();
221 if (loc.isInvalid()) loc = SS.getRange().getBegin();
222
223 // The type must be complete.
224 if (RequireCompleteType(loc, type, diag::err_incomplete_nested_name_spec,
225 SS.getRange())) {
226 SS.SetInvalid(SS.getRange());
227 return true;
228 }
229
230 if (auto *EnumD = dyn_cast<EnumDecl>(tag))
231 // Fixed enum types and scoped enum instantiations are complete, but they
232 // aren't valid as scopes until we see or instantiate their definition.
233 return RequireCompleteEnumDecl(EnumD, loc, &SS);
234
235 return false;
236 }
237
238 /// Require that the EnumDecl is completed with its enumerators defined or
239 /// instantiated. SS, if provided, is the ScopeRef parsed.
240 ///
RequireCompleteEnumDecl(EnumDecl * EnumD,SourceLocation L,CXXScopeSpec * SS)241 bool Sema::RequireCompleteEnumDecl(EnumDecl *EnumD, SourceLocation L,
242 CXXScopeSpec *SS) {
243 if (EnumD->isCompleteDefinition()) {
244 // If we know about the definition but it is not visible, complain.
245 NamedDecl *SuggestedDef = nullptr;
246 if (!hasVisibleDefinition(EnumD, &SuggestedDef,
247 /*OnlyNeedComplete*/false)) {
248 // If the user is going to see an error here, recover by making the
249 // definition visible.
250 bool TreatAsComplete = !isSFINAEContext();
251 diagnoseMissingImport(L, SuggestedDef, MissingImportKind::Definition,
252 /*Recover*/ TreatAsComplete);
253 return !TreatAsComplete;
254 }
255 return false;
256 }
257
258 // Try to instantiate the definition, if this is a specialization of an
259 // enumeration temploid.
260 if (EnumDecl *Pattern = EnumD->getInstantiatedFromMemberEnum()) {
261 MemberSpecializationInfo *MSI = EnumD->getMemberSpecializationInfo();
262 if (MSI->getTemplateSpecializationKind() != TSK_ExplicitSpecialization) {
263 if (InstantiateEnum(L, EnumD, Pattern,
264 getTemplateInstantiationArgs(EnumD),
265 TSK_ImplicitInstantiation)) {
266 if (SS)
267 SS->SetInvalid(SS->getRange());
268 return true;
269 }
270 return false;
271 }
272 }
273
274 if (SS) {
275 Diag(L, diag::err_incomplete_nested_name_spec)
276 << QualType(EnumD->getTypeForDecl(), 0) << SS->getRange();
277 SS->SetInvalid(SS->getRange());
278 } else {
279 Diag(L, diag::err_incomplete_enum) << QualType(EnumD->getTypeForDecl(), 0);
280 Diag(EnumD->getLocation(), diag::note_declared_at);
281 }
282
283 return true;
284 }
285
ActOnCXXGlobalScopeSpecifier(SourceLocation CCLoc,CXXScopeSpec & SS)286 bool Sema::ActOnCXXGlobalScopeSpecifier(SourceLocation CCLoc,
287 CXXScopeSpec &SS) {
288 SS.MakeGlobal(Context, CCLoc);
289 return false;
290 }
291
ActOnSuperScopeSpecifier(SourceLocation SuperLoc,SourceLocation ColonColonLoc,CXXScopeSpec & SS)292 bool Sema::ActOnSuperScopeSpecifier(SourceLocation SuperLoc,
293 SourceLocation ColonColonLoc,
294 CXXScopeSpec &SS) {
295 CXXRecordDecl *RD = nullptr;
296 for (Scope *S = getCurScope(); S; S = S->getParent()) {
297 if (S->isFunctionScope()) {
298 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(S->getEntity()))
299 RD = MD->getParent();
300 break;
301 }
302 if (S->isClassScope()) {
303 RD = cast<CXXRecordDecl>(S->getEntity());
304 break;
305 }
306 }
307
308 if (!RD) {
309 Diag(SuperLoc, diag::err_invalid_super_scope);
310 return true;
311 } else if (RD->isLambda()) {
312 Diag(SuperLoc, diag::err_super_in_lambda_unsupported);
313 return true;
314 } else if (RD->getNumBases() == 0) {
315 Diag(SuperLoc, diag::err_no_base_classes) << RD->getName();
316 return true;
317 }
318
319 SS.MakeSuper(Context, RD, SuperLoc, ColonColonLoc);
320 return false;
321 }
322
323 /// Determines whether the given declaration is an valid acceptable
324 /// result for name lookup of a nested-name-specifier.
325 /// \param SD Declaration checked for nested-name-specifier.
326 /// \param IsExtension If not null and the declaration is accepted as an
327 /// extension, the pointed variable is assigned true.
isAcceptableNestedNameSpecifier(const NamedDecl * SD,bool * IsExtension)328 bool Sema::isAcceptableNestedNameSpecifier(const NamedDecl *SD,
329 bool *IsExtension) {
330 if (!SD)
331 return false;
332
333 SD = SD->getUnderlyingDecl();
334
335 // Namespace and namespace aliases are fine.
336 if (isa<NamespaceDecl>(SD))
337 return true;
338
339 if (!isa<TypeDecl>(SD))
340 return false;
341
342 // Determine whether we have a class (or, in C++11, an enum) or
343 // a typedef thereof. If so, build the nested-name-specifier.
344 QualType T = Context.getTypeDeclType(cast<TypeDecl>(SD));
345 if (T->isDependentType())
346 return true;
347 if (const TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(SD)) {
348 if (TD->getUnderlyingType()->isRecordType())
349 return true;
350 if (TD->getUnderlyingType()->isEnumeralType()) {
351 if (Context.getLangOpts().CPlusPlus11)
352 return true;
353 if (IsExtension)
354 *IsExtension = true;
355 }
356 } else if (isa<RecordDecl>(SD)) {
357 return true;
358 } else if (isa<EnumDecl>(SD)) {
359 if (Context.getLangOpts().CPlusPlus11)
360 return true;
361 if (IsExtension)
362 *IsExtension = true;
363 }
364
365 return false;
366 }
367
368 /// If the given nested-name-specifier begins with a bare identifier
369 /// (e.g., Base::), perform name lookup for that identifier as a
370 /// nested-name-specifier within the given scope, and return the result of that
371 /// name lookup.
FindFirstQualifierInScope(Scope * S,NestedNameSpecifier * NNS)372 NamedDecl *Sema::FindFirstQualifierInScope(Scope *S, NestedNameSpecifier *NNS) {
373 if (!S || !NNS)
374 return nullptr;
375
376 while (NNS->getPrefix())
377 NNS = NNS->getPrefix();
378
379 if (NNS->getKind() != NestedNameSpecifier::Identifier)
380 return nullptr;
381
382 LookupResult Found(*this, NNS->getAsIdentifier(), SourceLocation(),
383 LookupNestedNameSpecifierName);
384 LookupName(Found, S);
385 assert(!Found.isAmbiguous() && "Cannot handle ambiguities here yet");
386
387 if (!Found.isSingleResult())
388 return nullptr;
389
390 NamedDecl *Result = Found.getFoundDecl();
391 if (isAcceptableNestedNameSpecifier(Result))
392 return Result;
393
394 return nullptr;
395 }
396
isNonTypeNestedNameSpecifier(Scope * S,CXXScopeSpec & SS,NestedNameSpecInfo & IdInfo)397 bool Sema::isNonTypeNestedNameSpecifier(Scope *S, CXXScopeSpec &SS,
398 NestedNameSpecInfo &IdInfo) {
399 QualType ObjectType = GetTypeFromParser(IdInfo.ObjectType);
400 LookupResult Found(*this, IdInfo.Identifier, IdInfo.IdentifierLoc,
401 LookupNestedNameSpecifierName);
402
403 // Determine where to perform name lookup
404 DeclContext *LookupCtx = nullptr;
405 bool isDependent = false;
406 if (!ObjectType.isNull()) {
407 // This nested-name-specifier occurs in a member access expression, e.g.,
408 // x->B::f, and we are looking into the type of the object.
409 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist");
410 LookupCtx = computeDeclContext(ObjectType);
411 isDependent = ObjectType->isDependentType();
412 } else if (SS.isSet()) {
413 // This nested-name-specifier occurs after another nested-name-specifier,
414 // so long into the context associated with the prior nested-name-specifier.
415 LookupCtx = computeDeclContext(SS, false);
416 isDependent = isDependentScopeSpecifier(SS);
417 Found.setContextRange(SS.getRange());
418 }
419
420 if (LookupCtx) {
421 // Perform "qualified" name lookup into the declaration context we
422 // computed, which is either the type of the base of a member access
423 // expression or the declaration context associated with a prior
424 // nested-name-specifier.
425
426 // The declaration context must be complete.
427 if (!LookupCtx->isDependentContext() &&
428 RequireCompleteDeclContext(SS, LookupCtx))
429 return false;
430
431 LookupQualifiedName(Found, LookupCtx);
432 } else if (isDependent) {
433 return false;
434 } else {
435 LookupName(Found, S);
436 }
437 Found.suppressDiagnostics();
438
439 return Found.getAsSingle<NamespaceDecl>();
440 }
441
442 namespace {
443
444 // Callback to only accept typo corrections that can be a valid C++ member
445 // initializer: either a non-static field member or a base class.
446 class NestedNameSpecifierValidatorCCC final
447 : public CorrectionCandidateCallback {
448 public:
NestedNameSpecifierValidatorCCC(Sema & SRef)449 explicit NestedNameSpecifierValidatorCCC(Sema &SRef)
450 : SRef(SRef) {}
451
ValidateCandidate(const TypoCorrection & candidate)452 bool ValidateCandidate(const TypoCorrection &candidate) override {
453 return SRef.isAcceptableNestedNameSpecifier(candidate.getCorrectionDecl());
454 }
455
clone()456 std::unique_ptr<CorrectionCandidateCallback> clone() override {
457 return std::make_unique<NestedNameSpecifierValidatorCCC>(*this);
458 }
459
460 private:
461 Sema &SRef;
462 };
463
464 }
465
466 /// Build a new nested-name-specifier for "identifier::", as described
467 /// by ActOnCXXNestedNameSpecifier.
468 ///
469 /// \param S Scope in which the nested-name-specifier occurs.
470 /// \param IdInfo Parser information about an identifier in the
471 /// nested-name-spec.
472 /// \param EnteringContext If true, enter the context specified by the
473 /// nested-name-specifier.
474 /// \param SS Optional nested name specifier preceding the identifier.
475 /// \param ScopeLookupResult Provides the result of name lookup within the
476 /// scope of the nested-name-specifier that was computed at template
477 /// definition time.
478 /// \param ErrorRecoveryLookup Specifies if the method is called to improve
479 /// error recovery and what kind of recovery is performed.
480 /// \param IsCorrectedToColon If not null, suggestion of replace '::' -> ':'
481 /// are allowed. The bool value pointed by this parameter is set to
482 /// 'true' if the identifier is treated as if it was followed by ':',
483 /// not '::'.
484 /// \param OnlyNamespace If true, only considers namespaces in lookup.
485 ///
486 /// This routine differs only slightly from ActOnCXXNestedNameSpecifier, in
487 /// that it contains an extra parameter \p ScopeLookupResult, which provides
488 /// the result of name lookup within the scope of the nested-name-specifier
489 /// that was computed at template definition time.
490 ///
491 /// If ErrorRecoveryLookup is true, then this call is used to improve error
492 /// recovery. This means that it should not emit diagnostics, it should
493 /// just return true on failure. It also means it should only return a valid
494 /// scope if it *knows* that the result is correct. It should not return in a
495 /// dependent context, for example. Nor will it extend \p SS with the scope
496 /// specifier.
BuildCXXNestedNameSpecifier(Scope * S,NestedNameSpecInfo & IdInfo,bool EnteringContext,CXXScopeSpec & SS,NamedDecl * ScopeLookupResult,bool ErrorRecoveryLookup,bool * IsCorrectedToColon,bool OnlyNamespace)497 bool Sema::BuildCXXNestedNameSpecifier(Scope *S, NestedNameSpecInfo &IdInfo,
498 bool EnteringContext, CXXScopeSpec &SS,
499 NamedDecl *ScopeLookupResult,
500 bool ErrorRecoveryLookup,
501 bool *IsCorrectedToColon,
502 bool OnlyNamespace) {
503 if (IdInfo.Identifier->isEditorPlaceholder())
504 return true;
505 LookupResult Found(*this, IdInfo.Identifier, IdInfo.IdentifierLoc,
506 OnlyNamespace ? LookupNamespaceName
507 : LookupNestedNameSpecifierName);
508 QualType ObjectType = GetTypeFromParser(IdInfo.ObjectType);
509
510 // Determine where to perform name lookup
511 DeclContext *LookupCtx = nullptr;
512 bool isDependent = false;
513 if (IsCorrectedToColon)
514 *IsCorrectedToColon = false;
515 if (!ObjectType.isNull()) {
516 // This nested-name-specifier occurs in a member access expression, e.g.,
517 // x->B::f, and we are looking into the type of the object.
518 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist");
519 LookupCtx = computeDeclContext(ObjectType);
520 isDependent = ObjectType->isDependentType();
521 } else if (SS.isSet()) {
522 // This nested-name-specifier occurs after another nested-name-specifier,
523 // so look into the context associated with the prior nested-name-specifier.
524 LookupCtx = computeDeclContext(SS, EnteringContext);
525 isDependent = isDependentScopeSpecifier(SS);
526 Found.setContextRange(SS.getRange());
527 }
528
529 bool ObjectTypeSearchedInScope = false;
530 if (LookupCtx) {
531 // Perform "qualified" name lookup into the declaration context we
532 // computed, which is either the type of the base of a member access
533 // expression or the declaration context associated with a prior
534 // nested-name-specifier.
535
536 // The declaration context must be complete.
537 if (!LookupCtx->isDependentContext() &&
538 RequireCompleteDeclContext(SS, LookupCtx))
539 return true;
540
541 LookupQualifiedName(Found, LookupCtx);
542
543 if (!ObjectType.isNull() && Found.empty()) {
544 // C++ [basic.lookup.classref]p4:
545 // If the id-expression in a class member access is a qualified-id of
546 // the form
547 //
548 // class-name-or-namespace-name::...
549 //
550 // the class-name-or-namespace-name following the . or -> operator is
551 // looked up both in the context of the entire postfix-expression and in
552 // the scope of the class of the object expression. If the name is found
553 // only in the scope of the class of the object expression, the name
554 // shall refer to a class-name. If the name is found only in the
555 // context of the entire postfix-expression, the name shall refer to a
556 // class-name or namespace-name. [...]
557 //
558 // Qualified name lookup into a class will not find a namespace-name,
559 // so we do not need to diagnose that case specifically. However,
560 // this qualified name lookup may find nothing. In that case, perform
561 // unqualified name lookup in the given scope (if available) or
562 // reconstruct the result from when name lookup was performed at template
563 // definition time.
564 if (S)
565 LookupName(Found, S);
566 else if (ScopeLookupResult)
567 Found.addDecl(ScopeLookupResult);
568
569 ObjectTypeSearchedInScope = true;
570 }
571 } else if (!isDependent) {
572 // Perform unqualified name lookup in the current scope.
573 LookupName(Found, S);
574 }
575
576 if (Found.isAmbiguous())
577 return true;
578
579 // If we performed lookup into a dependent context and did not find anything,
580 // that's fine: just build a dependent nested-name-specifier.
581 if (Found.empty() && isDependent &&
582 !(LookupCtx && LookupCtx->isRecord() &&
583 (!cast<CXXRecordDecl>(LookupCtx)->hasDefinition() ||
584 !cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases()))) {
585 // Don't speculate if we're just trying to improve error recovery.
586 if (ErrorRecoveryLookup)
587 return true;
588
589 // We were not able to compute the declaration context for a dependent
590 // base object type or prior nested-name-specifier, so this
591 // nested-name-specifier refers to an unknown specialization. Just build
592 // a dependent nested-name-specifier.
593 SS.Extend(Context, IdInfo.Identifier, IdInfo.IdentifierLoc, IdInfo.CCLoc);
594 return false;
595 }
596
597 if (Found.empty() && !ErrorRecoveryLookup) {
598 // If identifier is not found as class-name-or-namespace-name, but is found
599 // as other entity, don't look for typos.
600 LookupResult R(*this, Found.getLookupNameInfo(), LookupOrdinaryName);
601 if (LookupCtx)
602 LookupQualifiedName(R, LookupCtx);
603 else if (S && !isDependent)
604 LookupName(R, S);
605 if (!R.empty()) {
606 // Don't diagnose problems with this speculative lookup.
607 R.suppressDiagnostics();
608 // The identifier is found in ordinary lookup. If correction to colon is
609 // allowed, suggest replacement to ':'.
610 if (IsCorrectedToColon) {
611 *IsCorrectedToColon = true;
612 Diag(IdInfo.CCLoc, diag::err_nested_name_spec_is_not_class)
613 << IdInfo.Identifier << getLangOpts().CPlusPlus
614 << FixItHint::CreateReplacement(IdInfo.CCLoc, ":");
615 if (NamedDecl *ND = R.getAsSingle<NamedDecl>())
616 Diag(ND->getLocation(), diag::note_declared_at);
617 return true;
618 }
619 // Replacement '::' -> ':' is not allowed, just issue respective error.
620 Diag(R.getNameLoc(), OnlyNamespace
621 ? unsigned(diag::err_expected_namespace_name)
622 : unsigned(diag::err_expected_class_or_namespace))
623 << IdInfo.Identifier << getLangOpts().CPlusPlus;
624 if (NamedDecl *ND = R.getAsSingle<NamedDecl>())
625 Diag(ND->getLocation(), diag::note_entity_declared_at)
626 << IdInfo.Identifier;
627 return true;
628 }
629 }
630
631 if (Found.empty() && !ErrorRecoveryLookup && !getLangOpts().MSVCCompat) {
632 // We haven't found anything, and we're not recovering from a
633 // different kind of error, so look for typos.
634 DeclarationName Name = Found.getLookupName();
635 Found.clear();
636 NestedNameSpecifierValidatorCCC CCC(*this);
637 if (TypoCorrection Corrected = CorrectTypo(
638 Found.getLookupNameInfo(), Found.getLookupKind(), S, &SS, CCC,
639 CTK_ErrorRecovery, LookupCtx, EnteringContext)) {
640 if (LookupCtx) {
641 bool DroppedSpecifier =
642 Corrected.WillReplaceSpecifier() &&
643 Name.getAsString() == Corrected.getAsString(getLangOpts());
644 if (DroppedSpecifier)
645 SS.clear();
646 diagnoseTypo(Corrected, PDiag(diag::err_no_member_suggest)
647 << Name << LookupCtx << DroppedSpecifier
648 << SS.getRange());
649 } else
650 diagnoseTypo(Corrected, PDiag(diag::err_undeclared_var_use_suggest)
651 << Name);
652
653 if (Corrected.getCorrectionSpecifier())
654 SS.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
655 SourceRange(Found.getNameLoc()));
656
657 if (NamedDecl *ND = Corrected.getFoundDecl())
658 Found.addDecl(ND);
659 Found.setLookupName(Corrected.getCorrection());
660 } else {
661 Found.setLookupName(IdInfo.Identifier);
662 }
663 }
664
665 NamedDecl *SD =
666 Found.isSingleResult() ? Found.getRepresentativeDecl() : nullptr;
667 bool IsExtension = false;
668 bool AcceptSpec = isAcceptableNestedNameSpecifier(SD, &IsExtension);
669 if (!AcceptSpec && IsExtension) {
670 AcceptSpec = true;
671 Diag(IdInfo.IdentifierLoc, diag::ext_nested_name_spec_is_enum);
672 }
673 if (AcceptSpec) {
674 if (!ObjectType.isNull() && !ObjectTypeSearchedInScope &&
675 !getLangOpts().CPlusPlus11) {
676 // C++03 [basic.lookup.classref]p4:
677 // [...] If the name is found in both contexts, the
678 // class-name-or-namespace-name shall refer to the same entity.
679 //
680 // We already found the name in the scope of the object. Now, look
681 // into the current scope (the scope of the postfix-expression) to
682 // see if we can find the same name there. As above, if there is no
683 // scope, reconstruct the result from the template instantiation itself.
684 //
685 // Note that C++11 does *not* perform this redundant lookup.
686 NamedDecl *OuterDecl;
687 if (S) {
688 LookupResult FoundOuter(*this, IdInfo.Identifier, IdInfo.IdentifierLoc,
689 LookupNestedNameSpecifierName);
690 LookupName(FoundOuter, S);
691 OuterDecl = FoundOuter.getAsSingle<NamedDecl>();
692 } else
693 OuterDecl = ScopeLookupResult;
694
695 if (isAcceptableNestedNameSpecifier(OuterDecl) &&
696 OuterDecl->getCanonicalDecl() != SD->getCanonicalDecl() &&
697 (!isa<TypeDecl>(OuterDecl) || !isa<TypeDecl>(SD) ||
698 !Context.hasSameType(
699 Context.getTypeDeclType(cast<TypeDecl>(OuterDecl)),
700 Context.getTypeDeclType(cast<TypeDecl>(SD))))) {
701 if (ErrorRecoveryLookup)
702 return true;
703
704 Diag(IdInfo.IdentifierLoc,
705 diag::err_nested_name_member_ref_lookup_ambiguous)
706 << IdInfo.Identifier;
707 Diag(SD->getLocation(), diag::note_ambig_member_ref_object_type)
708 << ObjectType;
709 Diag(OuterDecl->getLocation(), diag::note_ambig_member_ref_scope);
710
711 // Fall through so that we'll pick the name we found in the object
712 // type, since that's probably what the user wanted anyway.
713 }
714 }
715
716 if (auto *TD = dyn_cast_or_null<TypedefNameDecl>(SD))
717 MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false);
718
719 // If we're just performing this lookup for error-recovery purposes,
720 // don't extend the nested-name-specifier. Just return now.
721 if (ErrorRecoveryLookup)
722 return false;
723
724 // The use of a nested name specifier may trigger deprecation warnings.
725 DiagnoseUseOfDecl(SD, IdInfo.CCLoc);
726
727 if (NamespaceDecl *Namespace = dyn_cast<NamespaceDecl>(SD)) {
728 SS.Extend(Context, Namespace, IdInfo.IdentifierLoc, IdInfo.CCLoc);
729 return false;
730 }
731
732 if (NamespaceAliasDecl *Alias = dyn_cast<NamespaceAliasDecl>(SD)) {
733 SS.Extend(Context, Alias, IdInfo.IdentifierLoc, IdInfo.CCLoc);
734 return false;
735 }
736
737 QualType T =
738 Context.getTypeDeclType(cast<TypeDecl>(SD->getUnderlyingDecl()));
739 TypeLocBuilder TLB;
740 if (isa<InjectedClassNameType>(T)) {
741 InjectedClassNameTypeLoc InjectedTL
742 = TLB.push<InjectedClassNameTypeLoc>(T);
743 InjectedTL.setNameLoc(IdInfo.IdentifierLoc);
744 } else if (isa<RecordType>(T)) {
745 RecordTypeLoc RecordTL = TLB.push<RecordTypeLoc>(T);
746 RecordTL.setNameLoc(IdInfo.IdentifierLoc);
747 } else if (isa<TypedefType>(T)) {
748 TypedefTypeLoc TypedefTL = TLB.push<TypedefTypeLoc>(T);
749 TypedefTL.setNameLoc(IdInfo.IdentifierLoc);
750 } else if (isa<EnumType>(T)) {
751 EnumTypeLoc EnumTL = TLB.push<EnumTypeLoc>(T);
752 EnumTL.setNameLoc(IdInfo.IdentifierLoc);
753 } else if (isa<TemplateTypeParmType>(T)) {
754 TemplateTypeParmTypeLoc TemplateTypeTL
755 = TLB.push<TemplateTypeParmTypeLoc>(T);
756 TemplateTypeTL.setNameLoc(IdInfo.IdentifierLoc);
757 } else if (isa<UnresolvedUsingType>(T)) {
758 UnresolvedUsingTypeLoc UnresolvedTL
759 = TLB.push<UnresolvedUsingTypeLoc>(T);
760 UnresolvedTL.setNameLoc(IdInfo.IdentifierLoc);
761 } else if (isa<SubstTemplateTypeParmType>(T)) {
762 SubstTemplateTypeParmTypeLoc TL
763 = TLB.push<SubstTemplateTypeParmTypeLoc>(T);
764 TL.setNameLoc(IdInfo.IdentifierLoc);
765 } else if (isa<SubstTemplateTypeParmPackType>(T)) {
766 SubstTemplateTypeParmPackTypeLoc TL
767 = TLB.push<SubstTemplateTypeParmPackTypeLoc>(T);
768 TL.setNameLoc(IdInfo.IdentifierLoc);
769 } else {
770 llvm_unreachable("Unhandled TypeDecl node in nested-name-specifier");
771 }
772
773 if (T->isEnumeralType())
774 Diag(IdInfo.IdentifierLoc, diag::warn_cxx98_compat_enum_nested_name_spec);
775
776 SS.Extend(Context, SourceLocation(), TLB.getTypeLocInContext(Context, T),
777 IdInfo.CCLoc);
778 return false;
779 }
780
781 // Otherwise, we have an error case. If we don't want diagnostics, just
782 // return an error now.
783 if (ErrorRecoveryLookup)
784 return true;
785
786 // If we didn't find anything during our lookup, try again with
787 // ordinary name lookup, which can help us produce better error
788 // messages.
789 if (Found.empty()) {
790 Found.clear(LookupOrdinaryName);
791 LookupName(Found, S);
792 }
793
794 // In Microsoft mode, if we are within a templated function and we can't
795 // resolve Identifier, then extend the SS with Identifier. This will have
796 // the effect of resolving Identifier during template instantiation.
797 // The goal is to be able to resolve a function call whose
798 // nested-name-specifier is located inside a dependent base class.
799 // Example:
800 //
801 // class C {
802 // public:
803 // static void foo2() { }
804 // };
805 // template <class T> class A { public: typedef C D; };
806 //
807 // template <class T> class B : public A<T> {
808 // public:
809 // void foo() { D::foo2(); }
810 // };
811 if (getLangOpts().MSVCCompat) {
812 DeclContext *DC = LookupCtx ? LookupCtx : CurContext;
813 if (DC->isDependentContext() && DC->isFunctionOrMethod()) {
814 CXXRecordDecl *ContainingClass = dyn_cast<CXXRecordDecl>(DC->getParent());
815 if (ContainingClass && ContainingClass->hasAnyDependentBases()) {
816 Diag(IdInfo.IdentifierLoc,
817 diag::ext_undeclared_unqual_id_with_dependent_base)
818 << IdInfo.Identifier << ContainingClass;
819 SS.Extend(Context, IdInfo.Identifier, IdInfo.IdentifierLoc,
820 IdInfo.CCLoc);
821 return false;
822 }
823 }
824 }
825
826 if (!Found.empty()) {
827 if (TypeDecl *TD = Found.getAsSingle<TypeDecl>())
828 Diag(IdInfo.IdentifierLoc, diag::err_expected_class_or_namespace)
829 << Context.getTypeDeclType(TD) << getLangOpts().CPlusPlus;
830 else {
831 Diag(IdInfo.IdentifierLoc, diag::err_expected_class_or_namespace)
832 << IdInfo.Identifier << getLangOpts().CPlusPlus;
833 if (NamedDecl *ND = Found.getAsSingle<NamedDecl>())
834 Diag(ND->getLocation(), diag::note_entity_declared_at)
835 << IdInfo.Identifier;
836 }
837 } else if (SS.isSet())
838 Diag(IdInfo.IdentifierLoc, diag::err_no_member) << IdInfo.Identifier
839 << LookupCtx << SS.getRange();
840 else
841 Diag(IdInfo.IdentifierLoc, diag::err_undeclared_var_use)
842 << IdInfo.Identifier;
843
844 return true;
845 }
846
ActOnCXXNestedNameSpecifier(Scope * S,NestedNameSpecInfo & IdInfo,bool EnteringContext,CXXScopeSpec & SS,bool ErrorRecoveryLookup,bool * IsCorrectedToColon,bool OnlyNamespace)847 bool Sema::ActOnCXXNestedNameSpecifier(Scope *S, NestedNameSpecInfo &IdInfo,
848 bool EnteringContext, CXXScopeSpec &SS,
849 bool ErrorRecoveryLookup,
850 bool *IsCorrectedToColon,
851 bool OnlyNamespace) {
852 if (SS.isInvalid())
853 return true;
854
855 return BuildCXXNestedNameSpecifier(S, IdInfo, EnteringContext, SS,
856 /*ScopeLookupResult=*/nullptr, false,
857 IsCorrectedToColon, OnlyNamespace);
858 }
859
ActOnCXXNestedNameSpecifierDecltype(CXXScopeSpec & SS,const DeclSpec & DS,SourceLocation ColonColonLoc)860 bool Sema::ActOnCXXNestedNameSpecifierDecltype(CXXScopeSpec &SS,
861 const DeclSpec &DS,
862 SourceLocation ColonColonLoc) {
863 if (SS.isInvalid() || DS.getTypeSpecType() == DeclSpec::TST_error)
864 return true;
865
866 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype);
867
868 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
869 if (T.isNull())
870 return true;
871
872 if (!T->isDependentType() && !T->getAs<TagType>()) {
873 Diag(DS.getTypeSpecTypeLoc(), diag::err_expected_class_or_namespace)
874 << T << getLangOpts().CPlusPlus;
875 return true;
876 }
877
878 TypeLocBuilder TLB;
879 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T);
880 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc());
881 SS.Extend(Context, SourceLocation(), TLB.getTypeLocInContext(Context, T),
882 ColonColonLoc);
883 return false;
884 }
885
886 /// IsInvalidUnlessNestedName - This method is used for error recovery
887 /// purposes to determine whether the specified identifier is only valid as
888 /// a nested name specifier, for example a namespace name. It is
889 /// conservatively correct to always return false from this method.
890 ///
891 /// The arguments are the same as those passed to ActOnCXXNestedNameSpecifier.
IsInvalidUnlessNestedName(Scope * S,CXXScopeSpec & SS,NestedNameSpecInfo & IdInfo,bool EnteringContext)892 bool Sema::IsInvalidUnlessNestedName(Scope *S, CXXScopeSpec &SS,
893 NestedNameSpecInfo &IdInfo,
894 bool EnteringContext) {
895 if (SS.isInvalid())
896 return false;
897
898 return !BuildCXXNestedNameSpecifier(S, IdInfo, EnteringContext, SS,
899 /*ScopeLookupResult=*/nullptr, true);
900 }
901
ActOnCXXNestedNameSpecifier(Scope * S,CXXScopeSpec & SS,SourceLocation TemplateKWLoc,TemplateTy OpaqueTemplate,SourceLocation TemplateNameLoc,SourceLocation LAngleLoc,ASTTemplateArgsPtr TemplateArgsIn,SourceLocation RAngleLoc,SourceLocation CCLoc,bool EnteringContext)902 bool Sema::ActOnCXXNestedNameSpecifier(Scope *S,
903 CXXScopeSpec &SS,
904 SourceLocation TemplateKWLoc,
905 TemplateTy OpaqueTemplate,
906 SourceLocation TemplateNameLoc,
907 SourceLocation LAngleLoc,
908 ASTTemplateArgsPtr TemplateArgsIn,
909 SourceLocation RAngleLoc,
910 SourceLocation CCLoc,
911 bool EnteringContext) {
912 if (SS.isInvalid())
913 return true;
914
915 TemplateName Template = OpaqueTemplate.get();
916
917 // Translate the parser's template argument list in our AST format.
918 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc);
919 translateTemplateArguments(TemplateArgsIn, TemplateArgs);
920
921 DependentTemplateName *DTN = Template.getAsDependentTemplateName();
922 if (DTN && DTN->isIdentifier()) {
923 // Handle a dependent template specialization for which we cannot resolve
924 // the template name.
925 assert(DTN->getQualifier() == SS.getScopeRep());
926 QualType T = Context.getDependentTemplateSpecializationType(ETK_None,
927 DTN->getQualifier(),
928 DTN->getIdentifier(),
929 TemplateArgs);
930
931 // Create source-location information for this type.
932 TypeLocBuilder Builder;
933 DependentTemplateSpecializationTypeLoc SpecTL
934 = Builder.push<DependentTemplateSpecializationTypeLoc>(T);
935 SpecTL.setElaboratedKeywordLoc(SourceLocation());
936 SpecTL.setQualifierLoc(SS.getWithLocInContext(Context));
937 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
938 SpecTL.setTemplateNameLoc(TemplateNameLoc);
939 SpecTL.setLAngleLoc(LAngleLoc);
940 SpecTL.setRAngleLoc(RAngleLoc);
941 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
942 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
943
944 SS.Extend(Context, TemplateKWLoc, Builder.getTypeLocInContext(Context, T),
945 CCLoc);
946 return false;
947 }
948
949 // If we assumed an undeclared identifier was a template name, try to
950 // typo-correct it now.
951 if (Template.getAsAssumedTemplateName() &&
952 resolveAssumedTemplateNameAsType(S, Template, TemplateNameLoc))
953 return true;
954
955 TemplateDecl *TD = Template.getAsTemplateDecl();
956 if (Template.getAsOverloadedTemplate() || DTN ||
957 isa<FunctionTemplateDecl>(TD) || isa<VarTemplateDecl>(TD)) {
958 SourceRange R(TemplateNameLoc, RAngleLoc);
959 if (SS.getRange().isValid())
960 R.setBegin(SS.getRange().getBegin());
961
962 Diag(CCLoc, diag::err_non_type_template_in_nested_name_specifier)
963 << (TD && isa<VarTemplateDecl>(TD)) << Template << R;
964 NoteAllFoundTemplates(Template);
965 return true;
966 }
967
968 // We were able to resolve the template name to an actual template.
969 // Build an appropriate nested-name-specifier.
970 QualType T = CheckTemplateIdType(Template, TemplateNameLoc, TemplateArgs);
971 if (T.isNull())
972 return true;
973
974 // Alias template specializations can produce types which are not valid
975 // nested name specifiers.
976 if (!T->isDependentType() && !T->getAs<TagType>()) {
977 Diag(TemplateNameLoc, diag::err_nested_name_spec_non_tag) << T;
978 NoteAllFoundTemplates(Template);
979 return true;
980 }
981
982 // Provide source-location information for the template specialization type.
983 TypeLocBuilder Builder;
984 TemplateSpecializationTypeLoc SpecTL
985 = Builder.push<TemplateSpecializationTypeLoc>(T);
986 SpecTL.setTemplateKeywordLoc(TemplateKWLoc);
987 SpecTL.setTemplateNameLoc(TemplateNameLoc);
988 SpecTL.setLAngleLoc(LAngleLoc);
989 SpecTL.setRAngleLoc(RAngleLoc);
990 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
991 SpecTL.setArgLocInfo(I, TemplateArgs[I].getLocInfo());
992
993
994 SS.Extend(Context, TemplateKWLoc, Builder.getTypeLocInContext(Context, T),
995 CCLoc);
996 return false;
997 }
998
999 namespace {
1000 /// A structure that stores a nested-name-specifier annotation,
1001 /// including both the nested-name-specifier
1002 struct NestedNameSpecifierAnnotation {
1003 NestedNameSpecifier *NNS;
1004 };
1005 }
1006
SaveNestedNameSpecifierAnnotation(CXXScopeSpec & SS)1007 void *Sema::SaveNestedNameSpecifierAnnotation(CXXScopeSpec &SS) {
1008 if (SS.isEmpty() || SS.isInvalid())
1009 return nullptr;
1010
1011 void *Mem = Context.Allocate(
1012 (sizeof(NestedNameSpecifierAnnotation) + SS.location_size()),
1013 alignof(NestedNameSpecifierAnnotation));
1014 NestedNameSpecifierAnnotation *Annotation
1015 = new (Mem) NestedNameSpecifierAnnotation;
1016 Annotation->NNS = SS.getScopeRep();
1017 memcpy(Annotation + 1, SS.location_data(), SS.location_size());
1018 return Annotation;
1019 }
1020
RestoreNestedNameSpecifierAnnotation(void * AnnotationPtr,SourceRange AnnotationRange,CXXScopeSpec & SS)1021 void Sema::RestoreNestedNameSpecifierAnnotation(void *AnnotationPtr,
1022 SourceRange AnnotationRange,
1023 CXXScopeSpec &SS) {
1024 if (!AnnotationPtr) {
1025 SS.SetInvalid(AnnotationRange);
1026 return;
1027 }
1028
1029 NestedNameSpecifierAnnotation *Annotation
1030 = static_cast<NestedNameSpecifierAnnotation *>(AnnotationPtr);
1031 SS.Adopt(NestedNameSpecifierLoc(Annotation->NNS, Annotation + 1));
1032 }
1033
ShouldEnterDeclaratorScope(Scope * S,const CXXScopeSpec & SS)1034 bool Sema::ShouldEnterDeclaratorScope(Scope *S, const CXXScopeSpec &SS) {
1035 assert(SS.isSet() && "Parser passed invalid CXXScopeSpec.");
1036
1037 // Don't enter a declarator context when the current context is an Objective-C
1038 // declaration.
1039 if (isa<ObjCContainerDecl>(CurContext) || isa<ObjCMethodDecl>(CurContext))
1040 return false;
1041
1042 NestedNameSpecifier *Qualifier = SS.getScopeRep();
1043
1044 // There are only two places a well-formed program may qualify a
1045 // declarator: first, when defining a namespace or class member
1046 // out-of-line, and second, when naming an explicitly-qualified
1047 // friend function. The latter case is governed by
1048 // C++03 [basic.lookup.unqual]p10:
1049 // In a friend declaration naming a member function, a name used
1050 // in the function declarator and not part of a template-argument
1051 // in a template-id is first looked up in the scope of the member
1052 // function's class. If it is not found, or if the name is part of
1053 // a template-argument in a template-id, the look up is as
1054 // described for unqualified names in the definition of the class
1055 // granting friendship.
1056 // i.e. we don't push a scope unless it's a class member.
1057
1058 switch (Qualifier->getKind()) {
1059 case NestedNameSpecifier::Global:
1060 case NestedNameSpecifier::Namespace:
1061 case NestedNameSpecifier::NamespaceAlias:
1062 // These are always namespace scopes. We never want to enter a
1063 // namespace scope from anything but a file context.
1064 return CurContext->getRedeclContext()->isFileContext();
1065
1066 case NestedNameSpecifier::Identifier:
1067 case NestedNameSpecifier::TypeSpec:
1068 case NestedNameSpecifier::TypeSpecWithTemplate:
1069 case NestedNameSpecifier::Super:
1070 // These are never namespace scopes.
1071 return true;
1072 }
1073
1074 llvm_unreachable("Invalid NestedNameSpecifier::Kind!");
1075 }
1076
1077 /// ActOnCXXEnterDeclaratorScope - Called when a C++ scope specifier (global
1078 /// scope or nested-name-specifier) is parsed, part of a declarator-id.
1079 /// After this method is called, according to [C++ 3.4.3p3], names should be
1080 /// looked up in the declarator-id's scope, until the declarator is parsed and
1081 /// ActOnCXXExitDeclaratorScope is called.
1082 /// The 'SS' should be a non-empty valid CXXScopeSpec.
ActOnCXXEnterDeclaratorScope(Scope * S,CXXScopeSpec & SS)1083 bool Sema::ActOnCXXEnterDeclaratorScope(Scope *S, CXXScopeSpec &SS) {
1084 assert(SS.isSet() && "Parser passed invalid CXXScopeSpec.");
1085
1086 if (SS.isInvalid()) return true;
1087
1088 DeclContext *DC = computeDeclContext(SS, true);
1089 if (!DC) return true;
1090
1091 // Before we enter a declarator's context, we need to make sure that
1092 // it is a complete declaration context.
1093 if (!DC->isDependentContext() && RequireCompleteDeclContext(SS, DC))
1094 return true;
1095
1096 EnterDeclaratorContext(S, DC);
1097
1098 // Rebuild the nested name specifier for the new scope.
1099 if (DC->isDependentContext())
1100 RebuildNestedNameSpecifierInCurrentInstantiation(SS);
1101
1102 return false;
1103 }
1104
1105 /// ActOnCXXExitDeclaratorScope - Called when a declarator that previously
1106 /// invoked ActOnCXXEnterDeclaratorScope(), is finished. 'SS' is the same
1107 /// CXXScopeSpec that was passed to ActOnCXXEnterDeclaratorScope as well.
1108 /// Used to indicate that names should revert to being looked up in the
1109 /// defining scope.
ActOnCXXExitDeclaratorScope(Scope * S,const CXXScopeSpec & SS)1110 void Sema::ActOnCXXExitDeclaratorScope(Scope *S, const CXXScopeSpec &SS) {
1111 assert(SS.isSet() && "Parser passed invalid CXXScopeSpec.");
1112 if (SS.isInvalid())
1113 return;
1114 assert(!SS.isInvalid() && computeDeclContext(SS, true) &&
1115 "exiting declarator scope we never really entered");
1116 ExitDeclaratorContext(S);
1117 }
1118