1 //===--- SemaExprMember.cpp - Semantic Analysis for Expressions -----------===//
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 semantic analysis member access expressions.
12 //===----------------------------------------------------------------------===//
13 #include "clang/Sema/SemaInternal.h"
14 #include "clang/AST/ASTLambda.h"
15 #include "clang/AST/DeclCXX.h"
16 #include "clang/AST/DeclObjC.h"
17 #include "clang/AST/DeclTemplate.h"
18 #include "clang/AST/ExprCXX.h"
19 #include "clang/AST/ExprObjC.h"
20 #include "clang/Lex/Preprocessor.h"
21 #include "clang/Sema/Lookup.h"
22 #include "clang/Sema/Scope.h"
23 #include "clang/Sema/ScopeInfo.h"
25 using namespace clang;
28 typedef llvm::SmallPtrSet<const CXXRecordDecl*, 4> BaseSet;
29 static bool BaseIsNotInSet(const CXXRecordDecl *Base, void *BasesPtr) {
30 const BaseSet &Bases = *reinterpret_cast<const BaseSet*>(BasesPtr);
31 return !Bases.count(Base->getCanonicalDecl());
34 /// Determines if the given class is provably not derived from all of
35 /// the prospective base classes.
36 static bool isProvablyNotDerivedFrom(Sema &SemaRef, CXXRecordDecl *Record,
37 const BaseSet &Bases) {
38 void *BasesPtr = const_cast<void*>(reinterpret_cast<const void*>(&Bases));
39 return BaseIsNotInSet(Record, BasesPtr) &&
40 Record->forallBases(BaseIsNotInSet, BasesPtr);
44 /// The reference is definitely not an instance member access.
47 /// The reference may be an implicit instance member access.
50 /// The reference may be to an instance member, but it might be invalid if
51 /// so, because the context is not an instance method.
52 IMA_Mixed_StaticContext,
54 /// The reference may be to an instance member, but it is invalid if
55 /// so, because the context is from an unrelated class.
58 /// The reference is definitely an implicit instance member access.
61 /// The reference may be to an unresolved using declaration.
64 /// The reference is a contextually-permitted abstract member reference.
67 /// The reference may be to an unresolved using declaration and the
68 /// context is not an instance method.
69 IMA_Unresolved_StaticContext,
71 // The reference refers to a field which is not a member of the containing
72 // class, which is allowed because we're in C++11 mode and the context is
74 IMA_Field_Uneval_Context,
76 /// All possible referrents are instance members and the current
77 /// context is not an instance method.
78 IMA_Error_StaticContext,
80 /// All possible referrents are instance members of an unrelated
85 /// The given lookup names class member(s) and is not being used for
86 /// an address-of-member expression. Classify the type of access
87 /// according to whether it's possible that this reference names an
88 /// instance member. This is best-effort in dependent contexts; it is okay to
89 /// conservatively answer "yes", in which case some errors will simply
90 /// not be caught until template-instantiation.
91 static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef,
93 const LookupResult &R) {
94 assert(!R.empty() && (*R.begin())->isCXXClassMember());
96 DeclContext *DC = SemaRef.getFunctionLevelDeclContext();
98 bool isStaticContext = SemaRef.CXXThisTypeOverride.isNull() &&
99 (!isa<CXXMethodDecl>(DC) || cast<CXXMethodDecl>(DC)->isStatic());
101 if (R.isUnresolvableResult())
102 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved;
104 // Collect all the declaring classes of instance members we find.
105 bool hasNonInstance = false;
106 bool isField = false;
108 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) {
111 if (D->isCXXInstanceMember()) {
112 if (dyn_cast<FieldDecl>(D) || dyn_cast<MSPropertyDecl>(D)
113 || dyn_cast<IndirectFieldDecl>(D))
116 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext());
117 Classes.insert(R->getCanonicalDecl());
120 hasNonInstance = true;
123 // If we didn't find any instance members, it can't be an implicit
128 // C++11 [expr.prim.general]p12:
129 // An id-expression that denotes a non-static data member or non-static
130 // member function of a class can only be used:
132 // - if that id-expression denotes a non-static data member and it
133 // appears in an unevaluated operand.
135 // This rule is specific to C++11. However, we also permit this form
136 // in unevaluated inline assembly operands, like the operand to a SIZE.
137 IMAKind AbstractInstanceResult = IMA_Static; // happens to be 'false'
138 assert(!AbstractInstanceResult);
139 switch (SemaRef.ExprEvalContexts.back().Context) {
140 case Sema::Unevaluated:
141 if (isField && SemaRef.getLangOpts().CPlusPlus11)
142 AbstractInstanceResult = IMA_Field_Uneval_Context;
145 case Sema::UnevaluatedAbstract:
146 AbstractInstanceResult = IMA_Abstract;
149 case Sema::ConstantEvaluated:
150 case Sema::PotentiallyEvaluated:
151 case Sema::PotentiallyEvaluatedIfUsed:
155 // If the current context is not an instance method, it can't be
156 // an implicit member reference.
157 if (isStaticContext) {
159 return IMA_Mixed_StaticContext;
161 return AbstractInstanceResult ? AbstractInstanceResult
162 : IMA_Error_StaticContext;
165 CXXRecordDecl *contextClass;
166 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC))
167 contextClass = MD->getParent()->getCanonicalDecl();
169 contextClass = cast<CXXRecordDecl>(DC);
171 // [class.mfct.non-static]p3:
172 // ...is used in the body of a non-static member function of class X,
173 // if name lookup (3.4.1) resolves the name in the id-expression to a
174 // non-static non-type member of some class C [...]
175 // ...if C is not X or a base class of X, the class member access expression
177 if (R.getNamingClass() &&
178 contextClass->getCanonicalDecl() !=
179 R.getNamingClass()->getCanonicalDecl()) {
180 // If the naming class is not the current context, this was a qualified
181 // member name lookup, and it's sufficient to check that we have the naming
182 // class as a base class.
184 Classes.insert(R.getNamingClass()->getCanonicalDecl());
187 // If we can prove that the current context is unrelated to all the
188 // declaring classes, it can't be an implicit member reference (in
189 // which case it's an error if any of those members are selected).
190 if (isProvablyNotDerivedFrom(SemaRef, contextClass, Classes))
191 return hasNonInstance ? IMA_Mixed_Unrelated :
192 AbstractInstanceResult ? AbstractInstanceResult :
195 return (hasNonInstance ? IMA_Mixed : IMA_Instance);
198 /// Diagnose a reference to a field with no object available.
199 static void diagnoseInstanceReference(Sema &SemaRef,
200 const CXXScopeSpec &SS,
202 const DeclarationNameInfo &nameInfo) {
203 SourceLocation Loc = nameInfo.getLoc();
204 SourceRange Range(Loc);
205 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin());
207 DeclContext *FunctionLevelDC = SemaRef.getFunctionLevelDeclContext();
208 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FunctionLevelDC);
209 CXXRecordDecl *ContextClass = Method ? Method->getParent() : nullptr;
210 CXXRecordDecl *RepClass = dyn_cast<CXXRecordDecl>(Rep->getDeclContext());
212 bool InStaticMethod = Method && Method->isStatic();
213 bool IsField = isa<FieldDecl>(Rep) || isa<IndirectFieldDecl>(Rep);
215 if (IsField && InStaticMethod)
216 // "invalid use of member 'x' in static member function"
217 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method)
218 << Range << nameInfo.getName();
219 else if (ContextClass && RepClass && SS.isEmpty() && !InStaticMethod &&
220 !RepClass->Equals(ContextClass) && RepClass->Encloses(ContextClass))
221 // Unqualified lookup in a non-static member function found a member of an
223 SemaRef.Diag(Loc, diag::err_nested_non_static_member_use)
224 << IsField << RepClass << nameInfo.getName() << ContextClass << Range;
226 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use)
227 << nameInfo.getName() << Range;
229 SemaRef.Diag(Loc, diag::err_member_call_without_object)
233 /// Builds an expression which might be an implicit member expression.
235 Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS,
236 SourceLocation TemplateKWLoc,
238 const TemplateArgumentListInfo *TemplateArgs) {
239 switch (ClassifyImplicitMemberAccess(*this, CurScope, R)) {
241 return BuildImplicitMemberExpr(SS, TemplateKWLoc, R, TemplateArgs, true);
244 case IMA_Mixed_Unrelated:
246 return BuildImplicitMemberExpr(SS, TemplateKWLoc, R, TemplateArgs, false);
248 case IMA_Field_Uneval_Context:
249 Diag(R.getNameLoc(), diag::warn_cxx98_compat_non_static_member_use)
250 << R.getLookupNameInfo().getName();
254 case IMA_Mixed_StaticContext:
255 case IMA_Unresolved_StaticContext:
256 if (TemplateArgs || TemplateKWLoc.isValid())
257 return BuildTemplateIdExpr(SS, TemplateKWLoc, R, false, TemplateArgs);
258 return BuildDeclarationNameExpr(SS, R, false);
260 case IMA_Error_StaticContext:
261 case IMA_Error_Unrelated:
262 diagnoseInstanceReference(*this, SS, R.getRepresentativeDecl(),
263 R.getLookupNameInfo());
267 llvm_unreachable("unexpected instance member access kind");
270 /// Check an ext-vector component access expression.
272 /// VK should be set in advance to the value kind of the base
275 CheckExtVectorComponent(Sema &S, QualType baseType, ExprValueKind &VK,
276 SourceLocation OpLoc, const IdentifierInfo *CompName,
277 SourceLocation CompLoc) {
278 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements,
281 // FIXME: This logic can be greatly simplified by splitting it along
282 // halving/not halving and reworking the component checking.
283 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>();
285 // The vector accessor can't exceed the number of elements.
286 const char *compStr = CompName->getNameStart();
288 // This flag determines whether or not the component is one of the four
289 // special names that indicate a subset of exactly half the elements are
291 bool HalvingSwizzle = false;
293 // This flag determines whether or not CompName has an 's' char prefix,
294 // indicating that it is a string of hex values to be used as vector indices.
295 bool HexSwizzle = (*compStr == 's' || *compStr == 'S') && compStr[1];
297 bool HasRepeated = false;
298 bool HasIndex[16] = {};
302 // Check that we've found one of the special components, or that the component
303 // names must come from the same set.
304 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") ||
305 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) {
306 HalvingSwizzle = true;
307 } else if (!HexSwizzle &&
308 (Idx = vecType->getPointAccessorIdx(*compStr)) != -1) {
310 if (HasIndex[Idx]) HasRepeated = true;
311 HasIndex[Idx] = true;
313 } while (*compStr && (Idx = vecType->getPointAccessorIdx(*compStr)) != -1);
315 if (HexSwizzle) compStr++;
316 while ((Idx = vecType->getNumericAccessorIdx(*compStr)) != -1) {
317 if (HasIndex[Idx]) HasRepeated = true;
318 HasIndex[Idx] = true;
323 if (!HalvingSwizzle && *compStr) {
324 // We didn't get to the end of the string. This means the component names
325 // didn't come from the same set *or* we encountered an illegal name.
326 S.Diag(OpLoc, diag::err_ext_vector_component_name_illegal)
327 << StringRef(compStr, 1) << SourceRange(CompLoc);
331 // Ensure no component accessor exceeds the width of the vector type it
333 if (!HalvingSwizzle) {
334 compStr = CompName->getNameStart();
340 if (!vecType->isAccessorWithinNumElements(*compStr++)) {
341 S.Diag(OpLoc, diag::err_ext_vector_component_exceeds_length)
342 << baseType << SourceRange(CompLoc);
348 // The component accessor looks fine - now we need to compute the actual type.
349 // The vector type is implied by the component accessor. For example,
350 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc.
351 // vec4.s0 is a float, vec4.s23 is a vec3, etc.
352 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2.
353 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2
354 : CompName->getLength();
359 return vecType->getElementType();
361 if (HasRepeated) VK = VK_RValue;
363 QualType VT = S.Context.getExtVectorType(vecType->getElementType(), CompSize);
364 // Now look up the TypeDefDecl from the vector type. Without this,
365 // diagostics look bad. We want extended vector types to appear built-in.
366 for (Sema::ExtVectorDeclsType::iterator
367 I = S.ExtVectorDecls.begin(S.getExternalSource()),
368 E = S.ExtVectorDecls.end();
370 if ((*I)->getUnderlyingType() == VT)
371 return S.Context.getTypedefType(*I);
374 return VT; // should never get here (a typedef type should always be found).
377 static Decl *FindGetterSetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl,
378 IdentifierInfo *Member,
380 ASTContext &Context) {
382 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member))
384 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel))
387 for (const auto *I : PDecl->protocols()) {
388 if (Decl *D = FindGetterSetterNameDeclFromProtocolList(I, Member, Sel,
395 static Decl *FindGetterSetterNameDecl(const ObjCObjectPointerType *QIdTy,
396 IdentifierInfo *Member,
398 ASTContext &Context) {
399 // Check protocols on qualified interfaces.
400 Decl *GDecl = nullptr;
401 for (const auto *I : QIdTy->quals()) {
403 if (ObjCPropertyDecl *PD = I->FindPropertyDeclaration(Member)) {
407 // Also must look for a getter or setter name which uses property syntax.
408 if (ObjCMethodDecl *OMD = I->getInstanceMethod(Sel)) {
414 for (const auto *I : QIdTy->quals()) {
415 // Search in the protocol-qualifier list of current protocol.
416 GDecl = FindGetterSetterNameDeclFromProtocolList(I, Member, Sel, Context);
425 Sema::ActOnDependentMemberExpr(Expr *BaseExpr, QualType BaseType,
426 bool IsArrow, SourceLocation OpLoc,
427 const CXXScopeSpec &SS,
428 SourceLocation TemplateKWLoc,
429 NamedDecl *FirstQualifierInScope,
430 const DeclarationNameInfo &NameInfo,
431 const TemplateArgumentListInfo *TemplateArgs) {
432 // Even in dependent contexts, try to diagnose base expressions with
433 // obviously wrong types, e.g.:
438 // In Obj-C++, however, the above expression is valid, since it could be
439 // accessing the 'f' property if T is an Obj-C interface. The extra check
440 // allows this, while still reporting an error if T is a struct pointer.
442 const PointerType *PT = BaseType->getAs<PointerType>();
443 if (PT && (!getLangOpts().ObjC1 ||
444 PT->getPointeeType()->isRecordType())) {
445 assert(BaseExpr && "cannot happen with implicit member accesses");
446 Diag(OpLoc, diag::err_typecheck_member_reference_struct_union)
447 << BaseType << BaseExpr->getSourceRange() << NameInfo.getSourceRange();
452 assert(BaseType->isDependentType() ||
453 NameInfo.getName().isDependentName() ||
454 isDependentScopeSpecifier(SS));
456 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr
457 // must have pointer type, and the accessed type is the pointee.
458 return CXXDependentScopeMemberExpr::Create(
459 Context, BaseExpr, BaseType, IsArrow, OpLoc,
460 SS.getWithLocInContext(Context), TemplateKWLoc, FirstQualifierInScope,
461 NameInfo, TemplateArgs);
464 /// We know that the given qualified member reference points only to
465 /// declarations which do not belong to the static type of the base
466 /// expression. Diagnose the problem.
467 static void DiagnoseQualifiedMemberReference(Sema &SemaRef,
470 const CXXScopeSpec &SS,
472 const DeclarationNameInfo &nameInfo) {
473 // If this is an implicit member access, use a different set of
476 return diagnoseInstanceReference(SemaRef, SS, rep, nameInfo);
478 SemaRef.Diag(nameInfo.getLoc(), diag::err_qualified_member_of_unrelated)
479 << SS.getRange() << rep << BaseType;
482 // Check whether the declarations we found through a nested-name
483 // specifier in a member expression are actually members of the base
484 // type. The restriction here is:
487 // ... In these cases, the id-expression shall name a
488 // member of the class or of one of its base classes.
490 // So it's perfectly legitimate for the nested-name specifier to name
491 // an unrelated class, and for us to find an overload set including
492 // decls from classes which are not superclasses, as long as the decl
493 // we actually pick through overload resolution is from a superclass.
494 bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr,
496 const CXXScopeSpec &SS,
497 const LookupResult &R) {
498 CXXRecordDecl *BaseRecord =
499 cast_or_null<CXXRecordDecl>(computeDeclContext(BaseType));
501 // We can't check this yet because the base type is still
503 assert(BaseType->isDependentType());
507 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) {
508 // If this is an implicit member reference and we find a
509 // non-instance member, it's not an error.
510 if (!BaseExpr && !(*I)->isCXXInstanceMember())
513 // Note that we use the DC of the decl, not the underlying decl.
514 DeclContext *DC = (*I)->getDeclContext();
515 while (DC->isTransparentContext())
516 DC = DC->getParent();
521 CXXRecordDecl *MemberRecord = cast<CXXRecordDecl>(DC)->getCanonicalDecl();
522 if (BaseRecord->getCanonicalDecl() == MemberRecord ||
523 !BaseRecord->isProvablyNotDerivedFrom(MemberRecord))
527 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS,
528 R.getRepresentativeDecl(),
529 R.getLookupNameInfo());
535 // Callback to only accept typo corrections that are either a ValueDecl or a
536 // FunctionTemplateDecl and are declared in the current record or, for a C++
537 // classes, one of its base classes.
538 class RecordMemberExprValidatorCCC : public CorrectionCandidateCallback {
540 explicit RecordMemberExprValidatorCCC(const RecordType *RTy)
541 : Record(RTy->getDecl()) {}
543 bool ValidateCandidate(const TypoCorrection &candidate) override {
544 NamedDecl *ND = candidate.getCorrectionDecl();
545 // Don't accept candidates that cannot be member functions, constants,
546 // variables, or templates.
547 if (!ND || !(isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)))
550 // Accept candidates that occur in the current record.
551 if (Record->containsDecl(ND))
554 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Record)) {
555 // Accept candidates that occur in any of the current class' base classes.
556 for (const auto &BS : RD->bases()) {
557 if (const RecordType *BSTy = dyn_cast_or_null<RecordType>(
558 BS.getType().getTypePtrOrNull())) {
559 if (BSTy->getDecl()->containsDecl(ND))
569 const RecordDecl *const Record;
575 LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R,
576 SourceRange BaseRange, const RecordType *RTy,
577 SourceLocation OpLoc, CXXScopeSpec &SS,
578 bool HasTemplateArgs) {
579 RecordDecl *RDecl = RTy->getDecl();
580 if (!SemaRef.isThisOutsideMemberFunctionBody(QualType(RTy, 0)) &&
581 SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0),
582 diag::err_typecheck_incomplete_tag,
586 if (HasTemplateArgs) {
587 // LookupTemplateName doesn't expect these both to exist simultaneously.
588 QualType ObjectType = SS.isSet() ? QualType() : QualType(RTy, 0);
591 SemaRef.LookupTemplateName(R, nullptr, SS, ObjectType, false, MOUS);
595 DeclContext *DC = RDecl;
597 // If the member name was a qualified-id, look into the
598 // nested-name-specifier.
599 DC = SemaRef.computeDeclContext(SS, false);
601 if (SemaRef.RequireCompleteDeclContext(SS, DC)) {
602 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag)
603 << SS.getRange() << DC;
607 assert(DC && "Cannot handle non-computable dependent contexts in lookup");
609 if (!isa<TypeDecl>(DC)) {
610 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass)
611 << DC << SS.getRange();
616 // The record definition is complete, now look up the member.
617 SemaRef.LookupQualifiedName(R, DC);
622 // We didn't find anything with the given name, so try to correct
624 DeclarationName Name = R.getLookupName();
625 RecordMemberExprValidatorCCC Validator(RTy);
626 TypoCorrection Corrected = SemaRef.CorrectTypo(R.getLookupNameInfo(),
627 R.getLookupKind(), nullptr,
629 Sema::CTK_ErrorRecovery, DC);
631 if (Corrected.isResolved() && !Corrected.isKeyword()) {
632 R.setLookupName(Corrected.getCorrection());
633 for (TypoCorrection::decl_iterator DI = Corrected.begin(),
634 DIEnd = Corrected.end();
640 // If we're typo-correcting to an overloaded name, we don't yet have enough
641 // information to do overload resolution, so we don't know which previous
642 // declaration to point to.
643 if (Corrected.isOverloaded())
644 Corrected.setCorrectionDecl(nullptr);
645 bool DroppedSpecifier =
646 Corrected.WillReplaceSpecifier() &&
647 Name.getAsString() == Corrected.getAsString(SemaRef.getLangOpts());
648 SemaRef.diagnoseTypo(Corrected,
649 SemaRef.PDiag(diag::err_no_member_suggest)
650 << Name << DC << DroppedSpecifier << SS.getRange());
656 static ExprResult LookupMemberExpr(Sema &S, LookupResult &R,
657 ExprResult &BaseExpr, bool &IsArrow,
658 SourceLocation OpLoc, CXXScopeSpec &SS,
659 Decl *ObjCImpDecl, bool HasTemplateArgs);
662 Sema::BuildMemberReferenceExpr(Expr *Base, QualType BaseType,
663 SourceLocation OpLoc, bool IsArrow,
665 SourceLocation TemplateKWLoc,
666 NamedDecl *FirstQualifierInScope,
667 const DeclarationNameInfo &NameInfo,
668 const TemplateArgumentListInfo *TemplateArgs,
669 ActOnMemberAccessExtraArgs *ExtraArgs) {
670 if (BaseType->isDependentType() ||
671 (SS.isSet() && isDependentScopeSpecifier(SS)))
672 return ActOnDependentMemberExpr(Base, BaseType,
674 SS, TemplateKWLoc, FirstQualifierInScope,
675 NameInfo, TemplateArgs);
677 LookupResult R(*this, NameInfo, LookupMemberName);
679 // Implicit member accesses.
681 QualType RecordTy = BaseType;
682 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType();
683 if (LookupMemberExprInRecord(*this, R, SourceRange(),
684 RecordTy->getAs<RecordType>(),
685 OpLoc, SS, TemplateArgs != nullptr))
688 // Explicit member accesses.
690 ExprResult BaseResult = Base;
691 ExprResult Result = LookupMemberExpr(
692 *this, R, BaseResult, IsArrow, OpLoc, SS,
693 ExtraArgs ? ExtraArgs->ObjCImpDecl : nullptr,
694 TemplateArgs != nullptr);
696 if (BaseResult.isInvalid())
698 Base = BaseResult.get();
700 if (Result.isInvalid())
706 // LookupMemberExpr can modify Base, and thus change BaseType
707 BaseType = Base->getType();
710 return BuildMemberReferenceExpr(Base, BaseType,
711 OpLoc, IsArrow, SS, TemplateKWLoc,
712 FirstQualifierInScope, R, TemplateArgs,
717 BuildFieldReferenceExpr(Sema &S, Expr *BaseExpr, bool IsArrow,
718 const CXXScopeSpec &SS, FieldDecl *Field,
719 DeclAccessPair FoundDecl,
720 const DeclarationNameInfo &MemberNameInfo);
723 Sema::BuildAnonymousStructUnionMemberReference(const CXXScopeSpec &SS,
725 IndirectFieldDecl *indirectField,
726 DeclAccessPair foundDecl,
727 Expr *baseObjectExpr,
728 SourceLocation opLoc) {
729 // First, build the expression that refers to the base object.
731 bool baseObjectIsPointer = false;
732 Qualifiers baseQuals;
734 // Case 1: the base of the indirect field is not a field.
735 VarDecl *baseVariable = indirectField->getVarDecl();
736 CXXScopeSpec EmptySS;
738 assert(baseVariable->getType()->isRecordType());
740 // In principle we could have a member access expression that
741 // accesses an anonymous struct/union that's a static member of
742 // the base object's class. However, under the current standard,
743 // static data members cannot be anonymous structs or unions.
744 // Supporting this is as easy as building a MemberExpr here.
745 assert(!baseObjectExpr && "anonymous struct/union is static data member?");
747 DeclarationNameInfo baseNameInfo(DeclarationName(), loc);
750 = BuildDeclarationNameExpr(EmptySS, baseNameInfo, baseVariable);
751 if (result.isInvalid()) return ExprError();
753 baseObjectExpr = result.get();
754 baseObjectIsPointer = false;
755 baseQuals = baseObjectExpr->getType().getQualifiers();
757 // Case 2: the base of the indirect field is a field and the user
758 // wrote a member expression.
759 } else if (baseObjectExpr) {
760 // The caller provided the base object expression. Determine
761 // whether its a pointer and whether it adds any qualifiers to the
762 // anonymous struct/union fields we're looking into.
763 QualType objectType = baseObjectExpr->getType();
765 if (const PointerType *ptr = objectType->getAs<PointerType>()) {
766 baseObjectIsPointer = true;
767 objectType = ptr->getPointeeType();
769 baseObjectIsPointer = false;
771 baseQuals = objectType.getQualifiers();
773 // Case 3: the base of the indirect field is a field and we should
774 // build an implicit member access.
776 // We've found a member of an anonymous struct/union that is
777 // inside a non-anonymous struct/union, so in a well-formed
778 // program our base object expression is "this".
779 QualType ThisTy = getCurrentThisType();
780 if (ThisTy.isNull()) {
781 Diag(loc, diag::err_invalid_member_use_in_static_method)
782 << indirectField->getDeclName();
786 // Our base object expression is "this".
787 CheckCXXThisCapture(loc);
789 = new (Context) CXXThisExpr(loc, ThisTy, /*isImplicit=*/ true);
790 baseObjectIsPointer = true;
791 baseQuals = ThisTy->castAs<PointerType>()->getPointeeType().getQualifiers();
794 // Build the implicit member references to the field of the
795 // anonymous struct/union.
796 Expr *result = baseObjectExpr;
797 IndirectFieldDecl::chain_iterator
798 FI = indirectField->chain_begin(), FEnd = indirectField->chain_end();
800 // Build the first member access in the chain with full information.
802 FieldDecl *field = cast<FieldDecl>(*FI);
804 // Make a nameInfo that properly uses the anonymous name.
805 DeclarationNameInfo memberNameInfo(field->getDeclName(), loc);
807 result = BuildFieldReferenceExpr(*this, result, baseObjectIsPointer,
808 EmptySS, field, foundDecl,
809 memberNameInfo).get();
813 // FIXME: check qualified member access
816 // In all cases, we should now skip the first declaration in the chain.
820 FieldDecl *field = cast<FieldDecl>(*FI++);
822 // FIXME: these are somewhat meaningless
823 DeclarationNameInfo memberNameInfo(field->getDeclName(), loc);
824 DeclAccessPair fakeFoundDecl =
825 DeclAccessPair::make(field, field->getAccess());
827 result = BuildFieldReferenceExpr(*this, result, /*isarrow*/ false,
828 (FI == FEnd? SS : EmptySS), field,
829 fakeFoundDecl, memberNameInfo).get();
836 BuildMSPropertyRefExpr(Sema &S, Expr *BaseExpr, bool IsArrow,
837 const CXXScopeSpec &SS,
839 const DeclarationNameInfo &NameInfo) {
840 // Property names are always simple identifiers and therefore never
841 // require any interesting additional storage.
842 return new (S.Context) MSPropertyRefExpr(BaseExpr, PD, IsArrow,
843 S.Context.PseudoObjectTy, VK_LValue,
844 SS.getWithLocInContext(S.Context),
848 /// \brief Build a MemberExpr AST node.
850 BuildMemberExpr(Sema &SemaRef, ASTContext &C, Expr *Base, bool isArrow,
851 const CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
852 ValueDecl *Member, DeclAccessPair FoundDecl,
853 const DeclarationNameInfo &MemberNameInfo, QualType Ty,
854 ExprValueKind VK, ExprObjectKind OK,
855 const TemplateArgumentListInfo *TemplateArgs = nullptr) {
856 assert((!isArrow || Base->isRValue()) && "-> base must be a pointer rvalue");
858 MemberExpr::Create(C, Base, isArrow, SS.getWithLocInContext(C),
859 TemplateKWLoc, Member, FoundDecl, MemberNameInfo,
860 TemplateArgs, Ty, VK, OK);
861 SemaRef.MarkMemberReferenced(E);
866 Sema::BuildMemberReferenceExpr(Expr *BaseExpr, QualType BaseExprType,
867 SourceLocation OpLoc, bool IsArrow,
868 const CXXScopeSpec &SS,
869 SourceLocation TemplateKWLoc,
870 NamedDecl *FirstQualifierInScope,
872 const TemplateArgumentListInfo *TemplateArgs,
873 bool SuppressQualifierCheck,
874 ActOnMemberAccessExtraArgs *ExtraArgs) {
875 QualType BaseType = BaseExprType;
877 assert(BaseType->isPointerType());
878 BaseType = BaseType->castAs<PointerType>()->getPointeeType();
880 R.setBaseObjectType(BaseType);
882 LambdaScopeInfo *const CurLSI = getCurLambda();
883 // If this is an implicit member reference and the overloaded
884 // name refers to both static and non-static member functions
885 // (i.e. BaseExpr is null) and if we are currently processing a lambda,
886 // check if we should/can capture 'this'...
887 // Keep this example in mind:
890 // static void f(double) { }
893 // auto L = [=](auto a) {
894 // return [](int i) {
895 // return [=](auto b) {
897 // //f(decltype(a){});
903 // N(5.32); // OK, must not error.
908 if (!BaseExpr && CurLSI) {
909 SourceLocation Loc = R.getNameLoc();
910 if (SS.getRange().isValid())
911 Loc = SS.getRange().getBegin();
912 DeclContext *EnclosingFunctionCtx = CurContext->getParent()->getParent();
913 // If the enclosing function is not dependent, then this lambda is
914 // capture ready, so if we can capture this, do so.
915 if (!EnclosingFunctionCtx->isDependentContext()) {
916 // If the current lambda and all enclosing lambdas can capture 'this' -
917 // then go ahead and capture 'this' (since our unresolved overload set
918 // contains both static and non-static member functions).
919 if (!CheckCXXThisCapture(Loc, /*Explcit*/false, /*Diagnose*/false))
920 CheckCXXThisCapture(Loc);
921 } else if (CurContext->isDependentContext()) {
922 // ... since this is an implicit member reference, that might potentially
923 // involve a 'this' capture, mark 'this' for potential capture in
924 // enclosing lambdas.
925 if (CurLSI->ImpCaptureStyle != CurLSI->ImpCap_None)
926 CurLSI->addPotentialThisCapture(Loc);
929 const DeclarationNameInfo &MemberNameInfo = R.getLookupNameInfo();
930 DeclarationName MemberName = MemberNameInfo.getName();
931 SourceLocation MemberLoc = MemberNameInfo.getLoc();
937 // Rederive where we looked up.
938 DeclContext *DC = (SS.isSet()
939 ? computeDeclContext(SS, false)
940 : BaseType->getAs<RecordType>()->getDecl());
943 ExprResult RetryExpr;
944 if (!IsArrow && BaseExpr) {
945 SFINAETrap Trap(*this, true);
946 ParsedType ObjectType;
947 bool MayBePseudoDestructor = false;
948 RetryExpr = ActOnStartCXXMemberReference(getCurScope(), BaseExpr,
949 OpLoc, tok::arrow, ObjectType,
950 MayBePseudoDestructor);
951 if (RetryExpr.isUsable() && !Trap.hasErrorOccurred()) {
952 CXXScopeSpec TempSS(SS);
953 RetryExpr = ActOnMemberAccessExpr(
954 ExtraArgs->S, RetryExpr.get(), OpLoc, tok::arrow, TempSS,
955 TemplateKWLoc, ExtraArgs->Id, ExtraArgs->ObjCImpDecl,
956 ExtraArgs->HasTrailingLParen);
958 if (Trap.hasErrorOccurred())
959 RetryExpr = ExprError();
961 if (RetryExpr.isUsable()) {
962 Diag(OpLoc, diag::err_no_member_overloaded_arrow)
963 << MemberName << DC << FixItHint::CreateReplacement(OpLoc, "->");
968 Diag(R.getNameLoc(), diag::err_no_member)
970 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange());
974 // Diagnose lookups that find only declarations from a non-base
975 // type. This is possible for either qualified lookups (which may
976 // have been qualified with an unrelated type) or implicit member
977 // expressions (which were found with unqualified lookup and thus
978 // may have come from an enclosing scope). Note that it's okay for
979 // lookup to find declarations from a non-base type as long as those
980 // aren't the ones picked by overload resolution.
981 if ((SS.isSet() || !BaseExpr ||
982 (isa<CXXThisExpr>(BaseExpr) &&
983 cast<CXXThisExpr>(BaseExpr)->isImplicit())) &&
984 !SuppressQualifierCheck &&
985 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R))
988 // Construct an unresolved result if we in fact got an unresolved
990 if (R.isOverloadedResult() || R.isUnresolvableResult()) {
991 // Suppress any lookup-related diagnostics; we'll do these when we
993 R.suppressDiagnostics();
995 UnresolvedMemberExpr *MemExpr
996 = UnresolvedMemberExpr::Create(Context, R.isUnresolvableResult(),
997 BaseExpr, BaseExprType,
999 SS.getWithLocInContext(Context),
1000 TemplateKWLoc, MemberNameInfo,
1001 TemplateArgs, R.begin(), R.end());
1006 assert(R.isSingleResult());
1007 DeclAccessPair FoundDecl = R.begin().getPair();
1008 NamedDecl *MemberDecl = R.getFoundDecl();
1010 // FIXME: diagnose the presence of template arguments now.
1012 // If the decl being referenced had an error, return an error for this
1013 // sub-expr without emitting another error, in order to avoid cascading
1015 if (MemberDecl->isInvalidDecl())
1018 // Handle the implicit-member-access case.
1020 // If this is not an instance member, convert to a non-member access.
1021 if (!MemberDecl->isCXXInstanceMember())
1022 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), MemberDecl);
1024 SourceLocation Loc = R.getNameLoc();
1025 if (SS.getRange().isValid())
1026 Loc = SS.getRange().getBegin();
1027 CheckCXXThisCapture(Loc);
1028 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true);
1031 bool ShouldCheckUse = true;
1032 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) {
1033 // Don't diagnose the use of a virtual member function unless it's
1034 // explicitly qualified.
1035 if (MD->isVirtual() && !SS.isSet())
1036 ShouldCheckUse = false;
1039 // Check the use of this member.
1040 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc))
1043 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl))
1044 return BuildFieldReferenceExpr(*this, BaseExpr, IsArrow,
1045 SS, FD, FoundDecl, MemberNameInfo);
1047 if (MSPropertyDecl *PD = dyn_cast<MSPropertyDecl>(MemberDecl))
1048 return BuildMSPropertyRefExpr(*this, BaseExpr, IsArrow, SS, PD,
1051 if (IndirectFieldDecl *FD = dyn_cast<IndirectFieldDecl>(MemberDecl))
1052 // We may have found a field within an anonymous union or struct
1053 // (C++ [class.union]).
1054 return BuildAnonymousStructUnionMemberReference(SS, MemberLoc, FD,
1055 FoundDecl, BaseExpr,
1058 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) {
1059 return BuildMemberExpr(*this, Context, BaseExpr, IsArrow, SS, TemplateKWLoc,
1060 Var, FoundDecl, MemberNameInfo,
1061 Var->getType().getNonReferenceType(), VK_LValue,
1065 if (CXXMethodDecl *MemberFn = dyn_cast<CXXMethodDecl>(MemberDecl)) {
1066 ExprValueKind valueKind;
1068 if (MemberFn->isInstance()) {
1069 valueKind = VK_RValue;
1070 type = Context.BoundMemberTy;
1072 valueKind = VK_LValue;
1073 type = MemberFn->getType();
1076 return BuildMemberExpr(*this, Context, BaseExpr, IsArrow, SS, TemplateKWLoc,
1077 MemberFn, FoundDecl, MemberNameInfo, type, valueKind,
1080 assert(!isa<FunctionDecl>(MemberDecl) && "member function not C++ method?");
1082 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) {
1083 return BuildMemberExpr(*this, Context, BaseExpr, IsArrow, SS, TemplateKWLoc,
1084 Enum, FoundDecl, MemberNameInfo, Enum->getType(),
1085 VK_RValue, OK_Ordinary);
1088 // We found something that we didn't expect. Complain.
1089 if (isa<TypeDecl>(MemberDecl))
1090 Diag(MemberLoc, diag::err_typecheck_member_reference_type)
1091 << MemberName << BaseType << int(IsArrow);
1093 Diag(MemberLoc, diag::err_typecheck_member_reference_unknown)
1094 << MemberName << BaseType << int(IsArrow);
1096 Diag(MemberDecl->getLocation(), diag::note_member_declared_here)
1098 R.suppressDiagnostics();
1102 /// Given that normal member access failed on the given expression,
1103 /// and given that the expression's type involves builtin-id or
1104 /// builtin-Class, decide whether substituting in the redefinition
1105 /// types would be profitable. The redefinition type is whatever
1106 /// this translation unit tried to typedef to id/Class; we store
1107 /// it to the side and then re-use it in places like this.
1108 static bool ShouldTryAgainWithRedefinitionType(Sema &S, ExprResult &base) {
1109 const ObjCObjectPointerType *opty
1110 = base.get()->getType()->getAs<ObjCObjectPointerType>();
1111 if (!opty) return false;
1113 const ObjCObjectType *ty = opty->getObjectType();
1116 if (ty->isObjCId()) {
1117 redef = S.Context.getObjCIdRedefinitionType();
1118 } else if (ty->isObjCClass()) {
1119 redef = S.Context.getObjCClassRedefinitionType();
1124 // Do the substitution as long as the redefinition type isn't just a
1125 // possibly-qualified pointer to builtin-id or builtin-Class again.
1126 opty = redef->getAs<ObjCObjectPointerType>();
1127 if (opty && !opty->getObjectType()->getInterface())
1130 base = S.ImpCastExprToType(base.get(), redef, CK_BitCast);
1134 static bool isRecordType(QualType T) {
1135 return T->isRecordType();
1137 static bool isPointerToRecordType(QualType T) {
1138 if (const PointerType *PT = T->getAs<PointerType>())
1139 return PT->getPointeeType()->isRecordType();
1143 /// Perform conversions on the LHS of a member access expression.
1145 Sema::PerformMemberExprBaseConversion(Expr *Base, bool IsArrow) {
1146 if (IsArrow && !Base->getType()->isFunctionType())
1147 return DefaultFunctionArrayLvalueConversion(Base);
1149 return CheckPlaceholderExpr(Base);
1152 /// Look up the given member of the given non-type-dependent
1153 /// expression. This can return in one of two ways:
1154 /// * If it returns a sentinel null-but-valid result, the caller will
1155 /// assume that lookup was performed and the results written into
1156 /// the provided structure. It will take over from there.
1157 /// * Otherwise, the returned expression will be produced in place of
1158 /// an ordinary member expression.
1160 /// The ObjCImpDecl bit is a gross hack that will need to be properly
1161 /// fixed for ObjC++.
1162 static ExprResult LookupMemberExpr(Sema &S, LookupResult &R,
1163 ExprResult &BaseExpr, bool &IsArrow,
1164 SourceLocation OpLoc, CXXScopeSpec &SS,
1165 Decl *ObjCImpDecl, bool HasTemplateArgs) {
1166 assert(BaseExpr.get() && "no base expression");
1168 // Perform default conversions.
1169 BaseExpr = S.PerformMemberExprBaseConversion(BaseExpr.get(), IsArrow);
1170 if (BaseExpr.isInvalid())
1173 QualType BaseType = BaseExpr.get()->getType();
1174 assert(!BaseType->isDependentType());
1176 DeclarationName MemberName = R.getLookupName();
1177 SourceLocation MemberLoc = R.getNameLoc();
1179 // For later type-checking purposes, turn arrow accesses into dot
1180 // accesses. The only access type we support that doesn't follow
1181 // the C equivalence "a->b === (*a).b" is ObjC property accesses,
1182 // and those never use arrows, so this is unaffected.
1184 if (const PointerType *Ptr = BaseType->getAs<PointerType>())
1185 BaseType = Ptr->getPointeeType();
1186 else if (const ObjCObjectPointerType *Ptr
1187 = BaseType->getAs<ObjCObjectPointerType>())
1188 BaseType = Ptr->getPointeeType();
1189 else if (BaseType->isRecordType()) {
1190 // Recover from arrow accesses to records, e.g.:
1191 // struct MyRecord foo;
1193 // This is actually well-formed in C++ if MyRecord has an
1194 // overloaded operator->, but that should have been dealt with
1195 // by now--or a diagnostic message already issued if a problem
1196 // was encountered while looking for the overloaded operator->.
1197 if (!S.getLangOpts().CPlusPlus) {
1198 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
1199 << BaseType << int(IsArrow) << BaseExpr.get()->getSourceRange()
1200 << FixItHint::CreateReplacement(OpLoc, ".");
1203 } else if (BaseType->isFunctionType()) {
1206 S.Diag(MemberLoc, diag::err_typecheck_member_reference_arrow)
1207 << BaseType << BaseExpr.get()->getSourceRange();
1212 // Handle field access to simple records.
1213 if (const RecordType *RTy = BaseType->getAs<RecordType>()) {
1214 if (LookupMemberExprInRecord(S, R, BaseExpr.get()->getSourceRange(),
1215 RTy, OpLoc, SS, HasTemplateArgs))
1218 // Returning valid-but-null is how we indicate to the caller that
1219 // the lookup result was filled in.
1220 return ExprResult((Expr *)nullptr);
1223 // Handle ivar access to Objective-C objects.
1224 if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>()) {
1225 if (!SS.isEmpty() && !SS.isInvalid()) {
1226 S.Diag(SS.getRange().getBegin(), diag::err_qualified_objc_access)
1227 << 1 << SS.getScopeRep()
1228 << FixItHint::CreateRemoval(SS.getRange());
1232 IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
1234 // There are three cases for the base type:
1235 // - builtin id (qualified or unqualified)
1236 // - builtin Class (qualified or unqualified)
1238 ObjCInterfaceDecl *IDecl = OTy->getInterface();
1240 if (S.getLangOpts().ObjCAutoRefCount &&
1241 (OTy->isObjCId() || OTy->isObjCClass()))
1243 // There's an implicit 'isa' ivar on all objects.
1244 // But we only actually find it this way on objects of type 'id',
1246 if (OTy->isObjCId() && Member->isStr("isa"))
1247 return new (S.Context) ObjCIsaExpr(BaseExpr.get(), IsArrow, MemberLoc,
1248 OpLoc, S.Context.getObjCClassType());
1249 if (ShouldTryAgainWithRedefinitionType(S, BaseExpr))
1250 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1251 ObjCImpDecl, HasTemplateArgs);
1255 if (S.RequireCompleteType(OpLoc, BaseType,
1256 diag::err_typecheck_incomplete_tag,
1260 ObjCInterfaceDecl *ClassDeclared = nullptr;
1261 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared);
1264 // Attempt to correct for typos in ivar names.
1265 DeclFilterCCC<ObjCIvarDecl> Validator;
1266 Validator.IsObjCIvarLookup = IsArrow;
1267 if (TypoCorrection Corrected = S.CorrectTypo(
1268 R.getLookupNameInfo(), Sema::LookupMemberName, nullptr, nullptr,
1269 Validator, Sema::CTK_ErrorRecovery, IDecl)) {
1270 IV = Corrected.getCorrectionDeclAs<ObjCIvarDecl>();
1273 S.PDiag(diag::err_typecheck_member_reference_ivar_suggest)
1274 << IDecl->getDeclName() << MemberName);
1276 // Figure out the class that declares the ivar.
1277 assert(!ClassDeclared);
1278 Decl *D = cast<Decl>(IV->getDeclContext());
1279 if (ObjCCategoryDecl *CAT = dyn_cast<ObjCCategoryDecl>(D))
1280 D = CAT->getClassInterface();
1281 ClassDeclared = cast<ObjCInterfaceDecl>(D);
1283 if (IsArrow && IDecl->FindPropertyDeclaration(Member)) {
1284 S.Diag(MemberLoc, diag::err_property_found_suggest)
1285 << Member << BaseExpr.get()->getType()
1286 << FixItHint::CreateReplacement(OpLoc, ".");
1290 S.Diag(MemberLoc, diag::err_typecheck_member_reference_ivar)
1291 << IDecl->getDeclName() << MemberName
1292 << BaseExpr.get()->getSourceRange();
1297 assert(ClassDeclared);
1299 // If the decl being referenced had an error, return an error for this
1300 // sub-expr without emitting another error, in order to avoid cascading
1302 if (IV->isInvalidDecl())
1305 // Check whether we can reference this field.
1306 if (S.DiagnoseUseOfDecl(IV, MemberLoc))
1308 if (IV->getAccessControl() != ObjCIvarDecl::Public &&
1309 IV->getAccessControl() != ObjCIvarDecl::Package) {
1310 ObjCInterfaceDecl *ClassOfMethodDecl = nullptr;
1311 if (ObjCMethodDecl *MD = S.getCurMethodDecl())
1312 ClassOfMethodDecl = MD->getClassInterface();
1313 else if (ObjCImpDecl && S.getCurFunctionDecl()) {
1314 // Case of a c-function declared inside an objc implementation.
1315 // FIXME: For a c-style function nested inside an objc implementation
1316 // class, there is no implementation context available, so we pass
1317 // down the context as argument to this routine. Ideally, this context
1318 // need be passed down in the AST node and somehow calculated from the
1319 // AST for a function decl.
1320 if (ObjCImplementationDecl *IMPD =
1321 dyn_cast<ObjCImplementationDecl>(ObjCImpDecl))
1322 ClassOfMethodDecl = IMPD->getClassInterface();
1323 else if (ObjCCategoryImplDecl* CatImplClass =
1324 dyn_cast<ObjCCategoryImplDecl>(ObjCImpDecl))
1325 ClassOfMethodDecl = CatImplClass->getClassInterface();
1327 if (!S.getLangOpts().DebuggerSupport) {
1328 if (IV->getAccessControl() == ObjCIvarDecl::Private) {
1329 if (!declaresSameEntity(ClassDeclared, IDecl) ||
1330 !declaresSameEntity(ClassOfMethodDecl, ClassDeclared))
1331 S.Diag(MemberLoc, diag::error_private_ivar_access)
1332 << IV->getDeclName();
1333 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl))
1335 S.Diag(MemberLoc, diag::error_protected_ivar_access)
1336 << IV->getDeclName();
1340 if (S.getLangOpts().ObjCAutoRefCount) {
1341 Expr *BaseExp = BaseExpr.get()->IgnoreParenImpCasts();
1342 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(BaseExp))
1343 if (UO->getOpcode() == UO_Deref)
1344 BaseExp = UO->getSubExpr()->IgnoreParenCasts();
1346 if (DeclRefExpr *DE = dyn_cast<DeclRefExpr>(BaseExp))
1347 if (DE->getType().getObjCLifetime() == Qualifiers::OCL_Weak) {
1348 S.Diag(DE->getLocation(), diag::error_arc_weak_ivar_access);
1353 if (ObjCMethodDecl *MD = S.getCurMethodDecl()) {
1354 ObjCMethodFamily MF = MD->getMethodFamily();
1355 warn = (MF != OMF_init && MF != OMF_dealloc &&
1356 MF != OMF_finalize &&
1357 !S.IvarBacksCurrentMethodAccessor(IDecl, MD, IV));
1360 S.Diag(MemberLoc, diag::warn_direct_ivar_access) << IV->getDeclName();
1363 ObjCIvarRefExpr *Result = new (S.Context) ObjCIvarRefExpr(
1364 IV, IV->getType(), MemberLoc, OpLoc, BaseExpr.get(), IsArrow);
1366 if (S.getLangOpts().ObjCAutoRefCount) {
1367 if (IV->getType().getObjCLifetime() == Qualifiers::OCL_Weak) {
1368 if (!S.Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, MemberLoc))
1369 S.recordUseOfEvaluatedWeak(Result);
1376 // Objective-C property access.
1377 const ObjCObjectPointerType *OPT;
1378 if (!IsArrow && (OPT = BaseType->getAs<ObjCObjectPointerType>())) {
1379 if (!SS.isEmpty() && !SS.isInvalid()) {
1380 S.Diag(SS.getRange().getBegin(), diag::err_qualified_objc_access)
1381 << 0 << SS.getScopeRep() << FixItHint::CreateRemoval(SS.getRange());
1385 // This actually uses the base as an r-value.
1386 BaseExpr = S.DefaultLvalueConversion(BaseExpr.get());
1387 if (BaseExpr.isInvalid())
1390 assert(S.Context.hasSameUnqualifiedType(BaseType,
1391 BaseExpr.get()->getType()));
1393 IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
1395 const ObjCObjectType *OT = OPT->getObjectType();
1397 // id, with and without qualifiers.
1398 if (OT->isObjCId()) {
1399 // Check protocols on qualified interfaces.
1400 Selector Sel = S.PP.getSelectorTable().getNullarySelector(Member);
1402 FindGetterSetterNameDecl(OPT, Member, Sel, S.Context)) {
1403 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) {
1404 // Check the use of this declaration
1405 if (S.DiagnoseUseOfDecl(PD, MemberLoc))
1408 return new (S.Context)
1409 ObjCPropertyRefExpr(PD, S.Context.PseudoObjectTy, VK_LValue,
1410 OK_ObjCProperty, MemberLoc, BaseExpr.get());
1413 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) {
1414 // Check the use of this method.
1415 if (S.DiagnoseUseOfDecl(OMD, MemberLoc))
1417 Selector SetterSel =
1418 SelectorTable::constructSetterSelector(S.PP.getIdentifierTable(),
1419 S.PP.getSelectorTable(),
1421 ObjCMethodDecl *SMD = nullptr;
1422 if (Decl *SDecl = FindGetterSetterNameDecl(OPT,
1423 /*Property id*/ nullptr,
1424 SetterSel, S.Context))
1425 SMD = dyn_cast<ObjCMethodDecl>(SDecl);
1427 return new (S.Context)
1428 ObjCPropertyRefExpr(OMD, SMD, S.Context.PseudoObjectTy, VK_LValue,
1429 OK_ObjCProperty, MemberLoc, BaseExpr.get());
1432 // Use of id.member can only be for a property reference. Do not
1433 // use the 'id' redefinition in this case.
1434 if (IsArrow && ShouldTryAgainWithRedefinitionType(S, BaseExpr))
1435 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1436 ObjCImpDecl, HasTemplateArgs);
1438 return ExprError(S.Diag(MemberLoc, diag::err_property_not_found)
1439 << MemberName << BaseType);
1442 // 'Class', unqualified only.
1443 if (OT->isObjCClass()) {
1444 // Only works in a method declaration (??!).
1445 ObjCMethodDecl *MD = S.getCurMethodDecl();
1447 if (ShouldTryAgainWithRedefinitionType(S, BaseExpr))
1448 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1449 ObjCImpDecl, HasTemplateArgs);
1454 // Also must look for a getter name which uses property syntax.
1455 Selector Sel = S.PP.getSelectorTable().getNullarySelector(Member);
1456 ObjCInterfaceDecl *IFace = MD->getClassInterface();
1457 ObjCMethodDecl *Getter;
1458 if ((Getter = IFace->lookupClassMethod(Sel))) {
1459 // Check the use of this method.
1460 if (S.DiagnoseUseOfDecl(Getter, MemberLoc))
1463 Getter = IFace->lookupPrivateMethod(Sel, false);
1464 // If we found a getter then this may be a valid dot-reference, we
1465 // will look for the matching setter, in case it is needed.
1466 Selector SetterSel =
1467 SelectorTable::constructSetterSelector(S.PP.getIdentifierTable(),
1468 S.PP.getSelectorTable(),
1470 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel);
1472 // If this reference is in an @implementation, also check for 'private'
1474 Setter = IFace->lookupPrivateMethod(SetterSel, false);
1477 if (Setter && S.DiagnoseUseOfDecl(Setter, MemberLoc))
1480 if (Getter || Setter) {
1481 return new (S.Context) ObjCPropertyRefExpr(
1482 Getter, Setter, S.Context.PseudoObjectTy, VK_LValue,
1483 OK_ObjCProperty, MemberLoc, BaseExpr.get());
1486 if (ShouldTryAgainWithRedefinitionType(S, BaseExpr))
1487 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1488 ObjCImpDecl, HasTemplateArgs);
1490 return ExprError(S.Diag(MemberLoc, diag::err_property_not_found)
1491 << MemberName << BaseType);
1494 // Normal property access.
1495 return S.HandleExprPropertyRefExpr(OPT, BaseExpr.get(), OpLoc, MemberName,
1496 MemberLoc, SourceLocation(), QualType(),
1500 // Handle 'field access' to vectors, such as 'V.xx'.
1501 if (BaseType->isExtVectorType()) {
1502 // FIXME: this expr should store IsArrow.
1503 IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
1504 ExprValueKind VK = (IsArrow ? VK_LValue : BaseExpr.get()->getValueKind());
1505 QualType ret = CheckExtVectorComponent(S, BaseType, VK, OpLoc,
1510 return new (S.Context)
1511 ExtVectorElementExpr(ret, VK, BaseExpr.get(), *Member, MemberLoc);
1514 // Adjust builtin-sel to the appropriate redefinition type if that's
1515 // not just a pointer to builtin-sel again.
1516 if (IsArrow && BaseType->isSpecificBuiltinType(BuiltinType::ObjCSel) &&
1517 !S.Context.getObjCSelRedefinitionType()->isObjCSelType()) {
1518 BaseExpr = S.ImpCastExprToType(
1519 BaseExpr.get(), S.Context.getObjCSelRedefinitionType(), CK_BitCast);
1520 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1521 ObjCImpDecl, HasTemplateArgs);
1527 // Recover from dot accesses to pointers, e.g.:
1530 // This is actually well-formed in two cases:
1531 // - 'type' is an Objective C type
1532 // - 'bar' is a pseudo-destructor name which happens to refer to
1533 // the appropriate pointer type
1534 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) {
1535 if (!IsArrow && Ptr->getPointeeType()->isRecordType() &&
1536 MemberName.getNameKind() != DeclarationName::CXXDestructorName) {
1537 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
1538 << BaseType << int(IsArrow) << BaseExpr.get()->getSourceRange()
1539 << FixItHint::CreateReplacement(OpLoc, "->");
1541 // Recurse as an -> access.
1543 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1544 ObjCImpDecl, HasTemplateArgs);
1548 // If the user is trying to apply -> or . to a function name, it's probably
1549 // because they forgot parentheses to call that function.
1550 if (S.tryToRecoverWithCall(
1551 BaseExpr, S.PDiag(diag::err_member_reference_needs_call),
1553 IsArrow ? &isPointerToRecordType : &isRecordType)) {
1554 if (BaseExpr.isInvalid())
1556 BaseExpr = S.DefaultFunctionArrayConversion(BaseExpr.get());
1557 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1558 ObjCImpDecl, HasTemplateArgs);
1561 S.Diag(OpLoc, diag::err_typecheck_member_reference_struct_union)
1562 << BaseType << BaseExpr.get()->getSourceRange() << MemberLoc;
1567 /// The main callback when the parser finds something like
1568 /// expression . [nested-name-specifier] identifier
1569 /// expression -> [nested-name-specifier] identifier
1570 /// where 'identifier' encompasses a fairly broad spectrum of
1571 /// possibilities, including destructor and operator references.
1573 /// \param OpKind either tok::arrow or tok::period
1574 /// \param HasTrailingLParen whether the next token is '(', which
1575 /// is used to diagnose mis-uses of special members that can
1577 /// \param ObjCImpDecl the current Objective-C \@implementation
1578 /// decl; this is an ugly hack around the fact that Objective-C
1579 /// \@implementations aren't properly put in the context chain
1580 ExprResult Sema::ActOnMemberAccessExpr(Scope *S, Expr *Base,
1581 SourceLocation OpLoc,
1582 tok::TokenKind OpKind,
1584 SourceLocation TemplateKWLoc,
1587 bool HasTrailingLParen) {
1588 if (SS.isSet() && SS.isInvalid())
1591 // The only way a reference to a destructor can be used is to
1592 // immediately call it. If the next token is not a '(', produce
1593 // a diagnostic and build the call now.
1594 if (!HasTrailingLParen &&
1595 Id.getKind() == UnqualifiedId::IK_DestructorName) {
1596 ExprResult DtorAccess =
1597 ActOnMemberAccessExpr(S, Base, OpLoc, OpKind, SS, TemplateKWLoc, Id,
1598 ObjCImpDecl, /*HasTrailingLParen*/true);
1599 if (DtorAccess.isInvalid())
1601 return DiagnoseDtorReference(Id.getLocStart(), DtorAccess.get());
1604 // Warn about the explicit constructor calls Microsoft extension.
1605 if (getLangOpts().MicrosoftExt &&
1606 Id.getKind() == UnqualifiedId::IK_ConstructorName)
1607 Diag(Id.getSourceRange().getBegin(),
1608 diag::ext_ms_explicit_constructor_call);
1610 TemplateArgumentListInfo TemplateArgsBuffer;
1612 // Decompose the name into its component parts.
1613 DeclarationNameInfo NameInfo;
1614 const TemplateArgumentListInfo *TemplateArgs;
1615 DecomposeUnqualifiedId(Id, TemplateArgsBuffer,
1616 NameInfo, TemplateArgs);
1618 DeclarationName Name = NameInfo.getName();
1619 bool IsArrow = (OpKind == tok::arrow);
1621 NamedDecl *FirstQualifierInScope
1622 = (!SS.isSet() ? nullptr : FindFirstQualifierInScope(S, SS.getScopeRep()));
1624 // This is a postfix expression, so get rid of ParenListExprs.
1625 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base);
1626 if (Result.isInvalid()) return ExprError();
1627 Base = Result.get();
1629 if (Base->getType()->isDependentType() || Name.isDependentName() ||
1630 isDependentScopeSpecifier(SS)) {
1631 return ActOnDependentMemberExpr(Base, Base->getType(), IsArrow, OpLoc, SS,
1632 TemplateKWLoc, FirstQualifierInScope,
1633 NameInfo, TemplateArgs);
1636 ActOnMemberAccessExtraArgs ExtraArgs = {S, Id, ObjCImpDecl,
1638 return BuildMemberReferenceExpr(Base, Base->getType(), OpLoc, IsArrow, SS,
1639 TemplateKWLoc, FirstQualifierInScope,
1640 NameInfo, TemplateArgs, &ExtraArgs);
1644 BuildFieldReferenceExpr(Sema &S, Expr *BaseExpr, bool IsArrow,
1645 const CXXScopeSpec &SS, FieldDecl *Field,
1646 DeclAccessPair FoundDecl,
1647 const DeclarationNameInfo &MemberNameInfo) {
1648 // x.a is an l-value if 'a' has a reference type. Otherwise:
1649 // x.a is an l-value/x-value/pr-value if the base is (and note
1650 // that *x is always an l-value), except that if the base isn't
1651 // an ordinary object then we must have an rvalue.
1652 ExprValueKind VK = VK_LValue;
1653 ExprObjectKind OK = OK_Ordinary;
1655 if (BaseExpr->getObjectKind() == OK_Ordinary)
1656 VK = BaseExpr->getValueKind();
1660 if (VK != VK_RValue && Field->isBitField())
1663 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref]
1664 QualType MemberType = Field->getType();
1665 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) {
1666 MemberType = Ref->getPointeeType();
1669 QualType BaseType = BaseExpr->getType();
1670 if (IsArrow) BaseType = BaseType->getAs<PointerType>()->getPointeeType();
1672 Qualifiers BaseQuals = BaseType.getQualifiers();
1674 // GC attributes are never picked up by members.
1675 BaseQuals.removeObjCGCAttr();
1677 // CVR attributes from the base are picked up by members,
1678 // except that 'mutable' members don't pick up 'const'.
1679 if (Field->isMutable()) BaseQuals.removeConst();
1681 Qualifiers MemberQuals
1682 = S.Context.getCanonicalType(MemberType).getQualifiers();
1684 assert(!MemberQuals.hasAddressSpace());
1687 Qualifiers Combined = BaseQuals + MemberQuals;
1688 if (Combined != MemberQuals)
1689 MemberType = S.Context.getQualifiedType(MemberType, Combined);
1692 S.UnusedPrivateFields.remove(Field);
1695 S.PerformObjectMemberConversion(BaseExpr, SS.getScopeRep(),
1697 if (Base.isInvalid())
1699 return BuildMemberExpr(S, S.Context, Base.get(), IsArrow, SS,
1700 /*TemplateKWLoc=*/SourceLocation(), Field, FoundDecl,
1701 MemberNameInfo, MemberType, VK, OK);
1704 /// Builds an implicit member access expression. The current context
1705 /// is known to be an instance method, and the given unqualified lookup
1706 /// set is known to contain only instance members, at least one of which
1707 /// is from an appropriate type.
1709 Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS,
1710 SourceLocation TemplateKWLoc,
1712 const TemplateArgumentListInfo *TemplateArgs,
1713 bool IsKnownInstance) {
1714 assert(!R.empty() && !R.isAmbiguous());
1716 SourceLocation loc = R.getNameLoc();
1718 // If this is known to be an instance access, go ahead and build an
1719 // implicit 'this' expression now.
1720 // 'this' expression now.
1721 QualType ThisTy = getCurrentThisType();
1722 assert(!ThisTy.isNull() && "didn't correctly pre-flight capture of 'this'");
1724 Expr *baseExpr = nullptr; // null signifies implicit access
1725 if (IsKnownInstance) {
1726 SourceLocation Loc = R.getNameLoc();
1727 if (SS.getRange().isValid())
1728 Loc = SS.getRange().getBegin();
1729 CheckCXXThisCapture(Loc);
1730 baseExpr = new (Context) CXXThisExpr(loc, ThisTy, /*isImplicit=*/true);
1733 return BuildMemberReferenceExpr(baseExpr, ThisTy,
1734 /*OpLoc*/ SourceLocation(),
1737 /*FirstQualifierInScope*/ nullptr,