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/Overload.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"
24 #include "clang/Sema/SemaInternal.h"
26 using namespace clang;
29 typedef llvm::SmallPtrSet<const CXXRecordDecl*, 4> BaseSet;
30 static bool BaseIsNotInSet(const CXXRecordDecl *Base, void *BasesPtr) {
31 const BaseSet &Bases = *reinterpret_cast<const BaseSet*>(BasesPtr);
32 return !Bases.count(Base->getCanonicalDecl());
35 /// Determines if the given class is provably not derived from all of
36 /// the prospective base classes.
37 static bool isProvablyNotDerivedFrom(Sema &SemaRef, CXXRecordDecl *Record,
38 const BaseSet &Bases) {
39 void *BasesPtr = const_cast<void*>(reinterpret_cast<const void*>(&Bases));
40 return BaseIsNotInSet(Record, BasesPtr) &&
41 Record->forallBases(BaseIsNotInSet, BasesPtr);
45 /// The reference is definitely not an instance member access.
48 /// The reference may be an implicit instance member access.
51 /// The reference may be to an instance member, but it might be invalid if
52 /// so, because the context is not an instance method.
53 IMA_Mixed_StaticContext,
55 /// The reference may be to an instance member, but it is invalid if
56 /// so, because the context is from an unrelated class.
59 /// The reference is definitely an implicit instance member access.
62 /// The reference may be to an unresolved using declaration.
65 /// The reference is a contextually-permitted abstract member reference.
68 /// The reference may be to an unresolved using declaration and the
69 /// context is not an instance method.
70 IMA_Unresolved_StaticContext,
72 // The reference refers to a field which is not a member of the containing
73 // class, which is allowed because we're in C++11 mode and the context is
75 IMA_Field_Uneval_Context,
77 /// All possible referrents are instance members and the current
78 /// context is not an instance method.
79 IMA_Error_StaticContext,
81 /// All possible referrents are instance members of an unrelated
86 /// The given lookup names class member(s) and is not being used for
87 /// an address-of-member expression. Classify the type of access
88 /// according to whether it's possible that this reference names an
89 /// instance member. This is best-effort in dependent contexts; it is okay to
90 /// conservatively answer "yes", in which case some errors will simply
91 /// not be caught until template-instantiation.
92 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 // Look through using shadow decls and aliases.
208 Rep = Rep->getUnderlyingDecl();
210 DeclContext *FunctionLevelDC = SemaRef.getFunctionLevelDeclContext();
211 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FunctionLevelDC);
212 CXXRecordDecl *ContextClass = Method ? Method->getParent() : nullptr;
213 CXXRecordDecl *RepClass = dyn_cast<CXXRecordDecl>(Rep->getDeclContext());
215 bool InStaticMethod = Method && Method->isStatic();
216 bool IsField = isa<FieldDecl>(Rep) || isa<IndirectFieldDecl>(Rep);
218 if (IsField && InStaticMethod)
219 // "invalid use of member 'x' in static member function"
220 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method)
221 << Range << nameInfo.getName();
222 else if (ContextClass && RepClass && SS.isEmpty() && !InStaticMethod &&
223 !RepClass->Equals(ContextClass) && RepClass->Encloses(ContextClass))
224 // Unqualified lookup in a non-static member function found a member of an
226 SemaRef.Diag(Loc, diag::err_nested_non_static_member_use)
227 << IsField << RepClass << nameInfo.getName() << ContextClass << Range;
229 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use)
230 << nameInfo.getName() << Range;
232 SemaRef.Diag(Loc, diag::err_member_call_without_object)
236 /// Builds an expression which might be an implicit member expression.
238 Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS,
239 SourceLocation TemplateKWLoc,
241 const TemplateArgumentListInfo *TemplateArgs) {
242 switch (ClassifyImplicitMemberAccess(*this, R)) {
244 return BuildImplicitMemberExpr(SS, TemplateKWLoc, R, TemplateArgs, true);
247 case IMA_Mixed_Unrelated:
249 return BuildImplicitMemberExpr(SS, TemplateKWLoc, R, TemplateArgs, false);
251 case IMA_Field_Uneval_Context:
252 Diag(R.getNameLoc(), diag::warn_cxx98_compat_non_static_member_use)
253 << R.getLookupNameInfo().getName();
257 case IMA_Mixed_StaticContext:
258 case IMA_Unresolved_StaticContext:
259 if (TemplateArgs || TemplateKWLoc.isValid())
260 return BuildTemplateIdExpr(SS, TemplateKWLoc, R, false, TemplateArgs);
261 return BuildDeclarationNameExpr(SS, R, false);
263 case IMA_Error_StaticContext:
264 case IMA_Error_Unrelated:
265 diagnoseInstanceReference(*this, SS, R.getRepresentativeDecl(),
266 R.getLookupNameInfo());
270 llvm_unreachable("unexpected instance member access kind");
273 /// Check an ext-vector component access expression.
275 /// VK should be set in advance to the value kind of the base
278 CheckExtVectorComponent(Sema &S, QualType baseType, ExprValueKind &VK,
279 SourceLocation OpLoc, const IdentifierInfo *CompName,
280 SourceLocation CompLoc) {
281 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements,
284 // FIXME: This logic can be greatly simplified by splitting it along
285 // halving/not halving and reworking the component checking.
286 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>();
288 // The vector accessor can't exceed the number of elements.
289 const char *compStr = CompName->getNameStart();
291 // This flag determines whether or not the component is one of the four
292 // special names that indicate a subset of exactly half the elements are
294 bool HalvingSwizzle = false;
296 // This flag determines whether or not CompName has an 's' char prefix,
297 // indicating that it is a string of hex values to be used as vector indices.
298 bool HexSwizzle = (*compStr == 's' || *compStr == 'S') && compStr[1];
300 bool HasRepeated = false;
301 bool HasIndex[16] = {};
305 // Check that we've found one of the special components, or that the component
306 // names must come from the same set.
307 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") ||
308 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) {
309 HalvingSwizzle = true;
310 } else if (!HexSwizzle &&
311 (Idx = vecType->getPointAccessorIdx(*compStr)) != -1) {
313 if (HasIndex[Idx]) HasRepeated = true;
314 HasIndex[Idx] = true;
316 } while (*compStr && (Idx = vecType->getPointAccessorIdx(*compStr)) != -1);
318 if (HexSwizzle) compStr++;
319 while ((Idx = vecType->getNumericAccessorIdx(*compStr)) != -1) {
320 if (HasIndex[Idx]) HasRepeated = true;
321 HasIndex[Idx] = true;
326 if (!HalvingSwizzle && *compStr) {
327 // We didn't get to the end of the string. This means the component names
328 // didn't come from the same set *or* we encountered an illegal name.
329 S.Diag(OpLoc, diag::err_ext_vector_component_name_illegal)
330 << StringRef(compStr, 1) << SourceRange(CompLoc);
334 // Ensure no component accessor exceeds the width of the vector type it
336 if (!HalvingSwizzle) {
337 compStr = CompName->getNameStart();
343 if (!vecType->isAccessorWithinNumElements(*compStr++)) {
344 S.Diag(OpLoc, diag::err_ext_vector_component_exceeds_length)
345 << baseType << SourceRange(CompLoc);
351 // The component accessor looks fine - now we need to compute the actual type.
352 // The vector type is implied by the component accessor. For example,
353 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc.
354 // vec4.s0 is a float, vec4.s23 is a vec3, etc.
355 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2.
356 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2
357 : CompName->getLength();
362 return vecType->getElementType();
364 if (HasRepeated) VK = VK_RValue;
366 QualType VT = S.Context.getExtVectorType(vecType->getElementType(), CompSize);
367 // Now look up the TypeDefDecl from the vector type. Without this,
368 // diagostics look bad. We want extended vector types to appear built-in.
369 for (Sema::ExtVectorDeclsType::iterator
370 I = S.ExtVectorDecls.begin(S.getExternalSource()),
371 E = S.ExtVectorDecls.end();
373 if ((*I)->getUnderlyingType() == VT)
374 return S.Context.getTypedefType(*I);
377 return VT; // should never get here (a typedef type should always be found).
380 static Decl *FindGetterSetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl,
381 IdentifierInfo *Member,
383 ASTContext &Context) {
385 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member))
387 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel))
390 for (const auto *I : PDecl->protocols()) {
391 if (Decl *D = FindGetterSetterNameDeclFromProtocolList(I, Member, Sel,
398 static Decl *FindGetterSetterNameDecl(const ObjCObjectPointerType *QIdTy,
399 IdentifierInfo *Member,
401 ASTContext &Context) {
402 // Check protocols on qualified interfaces.
403 Decl *GDecl = nullptr;
404 for (const auto *I : QIdTy->quals()) {
406 if (ObjCPropertyDecl *PD = I->FindPropertyDeclaration(Member)) {
410 // Also must look for a getter or setter name which uses property syntax.
411 if (ObjCMethodDecl *OMD = I->getInstanceMethod(Sel)) {
417 for (const auto *I : QIdTy->quals()) {
418 // Search in the protocol-qualifier list of current protocol.
419 GDecl = FindGetterSetterNameDeclFromProtocolList(I, Member, Sel, Context);
428 Sema::ActOnDependentMemberExpr(Expr *BaseExpr, QualType BaseType,
429 bool IsArrow, SourceLocation OpLoc,
430 const CXXScopeSpec &SS,
431 SourceLocation TemplateKWLoc,
432 NamedDecl *FirstQualifierInScope,
433 const DeclarationNameInfo &NameInfo,
434 const TemplateArgumentListInfo *TemplateArgs) {
435 // Even in dependent contexts, try to diagnose base expressions with
436 // obviously wrong types, e.g.:
441 // In Obj-C++, however, the above expression is valid, since it could be
442 // accessing the 'f' property if T is an Obj-C interface. The extra check
443 // allows this, while still reporting an error if T is a struct pointer.
445 const PointerType *PT = BaseType->getAs<PointerType>();
446 if (PT && (!getLangOpts().ObjC1 ||
447 PT->getPointeeType()->isRecordType())) {
448 assert(BaseExpr && "cannot happen with implicit member accesses");
449 Diag(OpLoc, diag::err_typecheck_member_reference_struct_union)
450 << BaseType << BaseExpr->getSourceRange() << NameInfo.getSourceRange();
455 assert(BaseType->isDependentType() ||
456 NameInfo.getName().isDependentName() ||
457 isDependentScopeSpecifier(SS));
459 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr
460 // must have pointer type, and the accessed type is the pointee.
461 return CXXDependentScopeMemberExpr::Create(
462 Context, BaseExpr, BaseType, IsArrow, OpLoc,
463 SS.getWithLocInContext(Context), TemplateKWLoc, FirstQualifierInScope,
464 NameInfo, TemplateArgs);
467 /// We know that the given qualified member reference points only to
468 /// declarations which do not belong to the static type of the base
469 /// expression. Diagnose the problem.
470 static void DiagnoseQualifiedMemberReference(Sema &SemaRef,
473 const CXXScopeSpec &SS,
475 const DeclarationNameInfo &nameInfo) {
476 // If this is an implicit member access, use a different set of
479 return diagnoseInstanceReference(SemaRef, SS, rep, nameInfo);
481 SemaRef.Diag(nameInfo.getLoc(), diag::err_qualified_member_of_unrelated)
482 << SS.getRange() << rep << BaseType;
485 // Check whether the declarations we found through a nested-name
486 // specifier in a member expression are actually members of the base
487 // type. The restriction here is:
490 // ... In these cases, the id-expression shall name a
491 // member of the class or of one of its base classes.
493 // So it's perfectly legitimate for the nested-name specifier to name
494 // an unrelated class, and for us to find an overload set including
495 // decls from classes which are not superclasses, as long as the decl
496 // we actually pick through overload resolution is from a superclass.
497 bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr,
499 const CXXScopeSpec &SS,
500 const LookupResult &R) {
501 CXXRecordDecl *BaseRecord =
502 cast_or_null<CXXRecordDecl>(computeDeclContext(BaseType));
504 // We can't check this yet because the base type is still
506 assert(BaseType->isDependentType());
510 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) {
511 // If this is an implicit member reference and we find a
512 // non-instance member, it's not an error.
513 if (!BaseExpr && !(*I)->isCXXInstanceMember())
516 // Note that we use the DC of the decl, not the underlying decl.
517 DeclContext *DC = (*I)->getDeclContext();
518 while (DC->isTransparentContext())
519 DC = DC->getParent();
524 CXXRecordDecl *MemberRecord = cast<CXXRecordDecl>(DC)->getCanonicalDecl();
525 if (BaseRecord->getCanonicalDecl() == MemberRecord ||
526 !BaseRecord->isProvablyNotDerivedFrom(MemberRecord))
530 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS,
531 R.getRepresentativeDecl(),
532 R.getLookupNameInfo());
538 // Callback to only accept typo corrections that are either a ValueDecl or a
539 // FunctionTemplateDecl and are declared in the current record or, for a C++
540 // classes, one of its base classes.
541 class RecordMemberExprValidatorCCC : public CorrectionCandidateCallback {
543 explicit RecordMemberExprValidatorCCC(const RecordType *RTy)
544 : Record(RTy->getDecl()) {
545 // Don't add bare keywords to the consumer since they will always fail
546 // validation by virtue of not being associated with any decls.
547 WantTypeSpecifiers = false;
548 WantExpressionKeywords = false;
549 WantCXXNamedCasts = false;
550 WantFunctionLikeCasts = false;
551 WantRemainingKeywords = false;
554 bool ValidateCandidate(const TypoCorrection &candidate) override {
555 NamedDecl *ND = candidate.getCorrectionDecl();
556 // Don't accept candidates that cannot be member functions, constants,
557 // variables, or templates.
558 if (!ND || !(isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)))
561 // Accept candidates that occur in the current record.
562 if (Record->containsDecl(ND))
565 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Record)) {
566 // Accept candidates that occur in any of the current class' base classes.
567 for (const auto &BS : RD->bases()) {
568 if (const RecordType *BSTy =
569 dyn_cast_or_null<RecordType>(BS.getType().getTypePtrOrNull())) {
570 if (BSTy->getDecl()->containsDecl(ND))
580 const RecordDecl *const Record;
585 static bool LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R,
587 const RecordType *RTy,
588 SourceLocation OpLoc, bool IsArrow,
589 CXXScopeSpec &SS, bool HasTemplateArgs,
591 SourceRange BaseRange = BaseExpr ? BaseExpr->getSourceRange() : SourceRange();
592 RecordDecl *RDecl = RTy->getDecl();
593 if (!SemaRef.isThisOutsideMemberFunctionBody(QualType(RTy, 0)) &&
594 SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0),
595 diag::err_typecheck_incomplete_tag,
599 if (HasTemplateArgs) {
600 // LookupTemplateName doesn't expect these both to exist simultaneously.
601 QualType ObjectType = SS.isSet() ? QualType() : QualType(RTy, 0);
604 SemaRef.LookupTemplateName(R, nullptr, SS, ObjectType, false, MOUS);
608 DeclContext *DC = RDecl;
610 // If the member name was a qualified-id, look into the
611 // nested-name-specifier.
612 DC = SemaRef.computeDeclContext(SS, false);
614 if (SemaRef.RequireCompleteDeclContext(SS, DC)) {
615 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag)
616 << SS.getRange() << DC;
620 assert(DC && "Cannot handle non-computable dependent contexts in lookup");
622 if (!isa<TypeDecl>(DC)) {
623 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass)
624 << DC << SS.getRange();
629 // The record definition is complete, now look up the member.
630 SemaRef.LookupQualifiedName(R, DC, SS);
635 DeclarationName Typo = R.getLookupName();
636 SourceLocation TypoLoc = R.getNameLoc();
637 TE = SemaRef.CorrectTypoDelayed(
638 R.getLookupNameInfo(), R.getLookupKind(), nullptr, &SS,
639 llvm::make_unique<RecordMemberExprValidatorCCC>(RTy),
640 [=, &SemaRef](const TypoCorrection &TC) {
642 assert(!TC.isKeyword() &&
643 "Got a keyword as a correction for a member!");
644 bool DroppedSpecifier =
645 TC.WillReplaceSpecifier() &&
646 Typo.getAsString() == TC.getAsString(SemaRef.getLangOpts());
647 SemaRef.diagnoseTypo(TC, SemaRef.PDiag(diag::err_no_member_suggest)
648 << Typo << DC << DroppedSpecifier
651 SemaRef.Diag(TypoLoc, diag::err_no_member) << Typo << DC << BaseRange;
654 [=](Sema &SemaRef, TypoExpr *TE, TypoCorrection TC) mutable {
655 R.clear(); // Ensure there's no decls lingering in the shared state.
656 R.suppressDiagnostics();
657 R.setLookupName(TC.getCorrection());
658 for (NamedDecl *ND : TC)
661 return SemaRef.BuildMemberReferenceExpr(
662 BaseExpr, BaseExpr->getType(), OpLoc, IsArrow, SS, SourceLocation(),
663 nullptr, R, nullptr);
665 Sema::CTK_ErrorRecovery, DC);
670 static ExprResult LookupMemberExpr(Sema &S, LookupResult &R,
671 ExprResult &BaseExpr, bool &IsArrow,
672 SourceLocation OpLoc, CXXScopeSpec &SS,
673 Decl *ObjCImpDecl, bool HasTemplateArgs);
676 Sema::BuildMemberReferenceExpr(Expr *Base, QualType BaseType,
677 SourceLocation OpLoc, bool IsArrow,
679 SourceLocation TemplateKWLoc,
680 NamedDecl *FirstQualifierInScope,
681 const DeclarationNameInfo &NameInfo,
682 const TemplateArgumentListInfo *TemplateArgs,
683 ActOnMemberAccessExtraArgs *ExtraArgs) {
684 if (BaseType->isDependentType() ||
685 (SS.isSet() && isDependentScopeSpecifier(SS)))
686 return ActOnDependentMemberExpr(Base, BaseType,
688 SS, TemplateKWLoc, FirstQualifierInScope,
689 NameInfo, TemplateArgs);
691 LookupResult R(*this, NameInfo, LookupMemberName);
693 // Implicit member accesses.
695 TypoExpr *TE = nullptr;
696 QualType RecordTy = BaseType;
697 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType();
698 if (LookupMemberExprInRecord(*this, R, nullptr,
699 RecordTy->getAs<RecordType>(), OpLoc, IsArrow,
700 SS, TemplateArgs != nullptr, TE))
705 // Explicit member accesses.
707 ExprResult BaseResult = Base;
708 ExprResult Result = LookupMemberExpr(
709 *this, R, BaseResult, IsArrow, OpLoc, SS,
710 ExtraArgs ? ExtraArgs->ObjCImpDecl : nullptr,
711 TemplateArgs != nullptr);
713 if (BaseResult.isInvalid())
715 Base = BaseResult.get();
717 if (Result.isInvalid())
723 // LookupMemberExpr can modify Base, and thus change BaseType
724 BaseType = Base->getType();
727 return BuildMemberReferenceExpr(Base, BaseType,
728 OpLoc, IsArrow, SS, TemplateKWLoc,
729 FirstQualifierInScope, R, TemplateArgs,
734 BuildFieldReferenceExpr(Sema &S, Expr *BaseExpr, bool IsArrow,
735 const CXXScopeSpec &SS, FieldDecl *Field,
736 DeclAccessPair FoundDecl,
737 const DeclarationNameInfo &MemberNameInfo);
740 Sema::BuildAnonymousStructUnionMemberReference(const CXXScopeSpec &SS,
742 IndirectFieldDecl *indirectField,
743 DeclAccessPair foundDecl,
744 Expr *baseObjectExpr,
745 SourceLocation opLoc) {
746 // First, build the expression that refers to the base object.
748 bool baseObjectIsPointer = false;
749 Qualifiers baseQuals;
751 // Case 1: the base of the indirect field is not a field.
752 VarDecl *baseVariable = indirectField->getVarDecl();
753 CXXScopeSpec EmptySS;
755 assert(baseVariable->getType()->isRecordType());
757 // In principle we could have a member access expression that
758 // accesses an anonymous struct/union that's a static member of
759 // the base object's class. However, under the current standard,
760 // static data members cannot be anonymous structs or unions.
761 // Supporting this is as easy as building a MemberExpr here.
762 assert(!baseObjectExpr && "anonymous struct/union is static data member?");
764 DeclarationNameInfo baseNameInfo(DeclarationName(), loc);
767 = BuildDeclarationNameExpr(EmptySS, baseNameInfo, baseVariable);
768 if (result.isInvalid()) return ExprError();
770 baseObjectExpr = result.get();
771 baseObjectIsPointer = false;
772 baseQuals = baseObjectExpr->getType().getQualifiers();
774 // Case 2: the base of the indirect field is a field and the user
775 // wrote a member expression.
776 } else if (baseObjectExpr) {
777 // The caller provided the base object expression. Determine
778 // whether its a pointer and whether it adds any qualifiers to the
779 // anonymous struct/union fields we're looking into.
780 QualType objectType = baseObjectExpr->getType();
782 if (const PointerType *ptr = objectType->getAs<PointerType>()) {
783 baseObjectIsPointer = true;
784 objectType = ptr->getPointeeType();
786 baseObjectIsPointer = false;
788 baseQuals = objectType.getQualifiers();
790 // Case 3: the base of the indirect field is a field and we should
791 // build an implicit member access.
793 // We've found a member of an anonymous struct/union that is
794 // inside a non-anonymous struct/union, so in a well-formed
795 // program our base object expression is "this".
796 QualType ThisTy = getCurrentThisType();
797 if (ThisTy.isNull()) {
798 Diag(loc, diag::err_invalid_member_use_in_static_method)
799 << indirectField->getDeclName();
803 // Our base object expression is "this".
804 CheckCXXThisCapture(loc);
806 = new (Context) CXXThisExpr(loc, ThisTy, /*isImplicit=*/ true);
807 baseObjectIsPointer = true;
808 baseQuals = ThisTy->castAs<PointerType>()->getPointeeType().getQualifiers();
811 // Build the implicit member references to the field of the
812 // anonymous struct/union.
813 Expr *result = baseObjectExpr;
814 IndirectFieldDecl::chain_iterator
815 FI = indirectField->chain_begin(), FEnd = indirectField->chain_end();
817 // Build the first member access in the chain with full information.
819 FieldDecl *field = cast<FieldDecl>(*FI);
821 // Make a nameInfo that properly uses the anonymous name.
822 DeclarationNameInfo memberNameInfo(field->getDeclName(), loc);
824 result = BuildFieldReferenceExpr(*this, result, baseObjectIsPointer,
825 EmptySS, field, foundDecl,
826 memberNameInfo).get();
830 // FIXME: check qualified member access
833 // In all cases, we should now skip the first declaration in the chain.
837 FieldDecl *field = cast<FieldDecl>(*FI++);
839 // FIXME: these are somewhat meaningless
840 DeclarationNameInfo memberNameInfo(field->getDeclName(), loc);
841 DeclAccessPair fakeFoundDecl =
842 DeclAccessPair::make(field, field->getAccess());
844 result = BuildFieldReferenceExpr(*this, result, /*isarrow*/ false,
845 (FI == FEnd? SS : EmptySS), field,
846 fakeFoundDecl, memberNameInfo).get();
853 BuildMSPropertyRefExpr(Sema &S, Expr *BaseExpr, bool IsArrow,
854 const CXXScopeSpec &SS,
856 const DeclarationNameInfo &NameInfo) {
857 // Property names are always simple identifiers and therefore never
858 // require any interesting additional storage.
859 return new (S.Context) MSPropertyRefExpr(BaseExpr, PD, IsArrow,
860 S.Context.PseudoObjectTy, VK_LValue,
861 SS.getWithLocInContext(S.Context),
865 /// \brief Build a MemberExpr AST node.
867 BuildMemberExpr(Sema &SemaRef, ASTContext &C, Expr *Base, bool isArrow,
868 const CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
869 ValueDecl *Member, DeclAccessPair FoundDecl,
870 const DeclarationNameInfo &MemberNameInfo, QualType Ty,
871 ExprValueKind VK, ExprObjectKind OK,
872 const TemplateArgumentListInfo *TemplateArgs = nullptr) {
873 assert((!isArrow || Base->isRValue()) && "-> base must be a pointer rvalue");
875 MemberExpr::Create(C, Base, isArrow, SS.getWithLocInContext(C),
876 TemplateKWLoc, Member, FoundDecl, MemberNameInfo,
877 TemplateArgs, Ty, VK, OK);
878 SemaRef.MarkMemberReferenced(E);
883 Sema::BuildMemberReferenceExpr(Expr *BaseExpr, QualType BaseExprType,
884 SourceLocation OpLoc, bool IsArrow,
885 const CXXScopeSpec &SS,
886 SourceLocation TemplateKWLoc,
887 NamedDecl *FirstQualifierInScope,
889 const TemplateArgumentListInfo *TemplateArgs,
890 bool SuppressQualifierCheck,
891 ActOnMemberAccessExtraArgs *ExtraArgs) {
892 QualType BaseType = BaseExprType;
894 assert(BaseType->isPointerType());
895 BaseType = BaseType->castAs<PointerType>()->getPointeeType();
897 R.setBaseObjectType(BaseType);
899 LambdaScopeInfo *const CurLSI = getCurLambda();
900 // If this is an implicit member reference and the overloaded
901 // name refers to both static and non-static member functions
902 // (i.e. BaseExpr is null) and if we are currently processing a lambda,
903 // check if we should/can capture 'this'...
904 // Keep this example in mind:
907 // static void f(double) { }
910 // auto L = [=](auto a) {
911 // return [](int i) {
912 // return [=](auto b) {
914 // //f(decltype(a){});
920 // N(5.32); // OK, must not error.
925 if (!BaseExpr && CurLSI) {
926 SourceLocation Loc = R.getNameLoc();
927 if (SS.getRange().isValid())
928 Loc = SS.getRange().getBegin();
929 DeclContext *EnclosingFunctionCtx = CurContext->getParent()->getParent();
930 // If the enclosing function is not dependent, then this lambda is
931 // capture ready, so if we can capture this, do so.
932 if (!EnclosingFunctionCtx->isDependentContext()) {
933 // If the current lambda and all enclosing lambdas can capture 'this' -
934 // then go ahead and capture 'this' (since our unresolved overload set
935 // contains both static and non-static member functions).
936 if (!CheckCXXThisCapture(Loc, /*Explcit*/false, /*Diagnose*/false))
937 CheckCXXThisCapture(Loc);
938 } else if (CurContext->isDependentContext()) {
939 // ... since this is an implicit member reference, that might potentially
940 // involve a 'this' capture, mark 'this' for potential capture in
941 // enclosing lambdas.
942 if (CurLSI->ImpCaptureStyle != CurLSI->ImpCap_None)
943 CurLSI->addPotentialThisCapture(Loc);
946 const DeclarationNameInfo &MemberNameInfo = R.getLookupNameInfo();
947 DeclarationName MemberName = MemberNameInfo.getName();
948 SourceLocation MemberLoc = MemberNameInfo.getLoc();
954 // Rederive where we looked up.
955 DeclContext *DC = (SS.isSet()
956 ? computeDeclContext(SS, false)
957 : BaseType->getAs<RecordType>()->getDecl());
960 ExprResult RetryExpr;
961 if (!IsArrow && BaseExpr) {
962 SFINAETrap Trap(*this, true);
963 ParsedType ObjectType;
964 bool MayBePseudoDestructor = false;
965 RetryExpr = ActOnStartCXXMemberReference(getCurScope(), BaseExpr,
966 OpLoc, tok::arrow, ObjectType,
967 MayBePseudoDestructor);
968 if (RetryExpr.isUsable() && !Trap.hasErrorOccurred()) {
969 CXXScopeSpec TempSS(SS);
970 RetryExpr = ActOnMemberAccessExpr(
971 ExtraArgs->S, RetryExpr.get(), OpLoc, tok::arrow, TempSS,
972 TemplateKWLoc, ExtraArgs->Id, ExtraArgs->ObjCImpDecl,
973 ExtraArgs->HasTrailingLParen);
975 if (Trap.hasErrorOccurred())
976 RetryExpr = ExprError();
978 if (RetryExpr.isUsable()) {
979 Diag(OpLoc, diag::err_no_member_overloaded_arrow)
980 << MemberName << DC << FixItHint::CreateReplacement(OpLoc, "->");
985 Diag(R.getNameLoc(), diag::err_no_member)
987 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange());
991 // Diagnose lookups that find only declarations from a non-base
992 // type. This is possible for either qualified lookups (which may
993 // have been qualified with an unrelated type) or implicit member
994 // expressions (which were found with unqualified lookup and thus
995 // may have come from an enclosing scope). Note that it's okay for
996 // lookup to find declarations from a non-base type as long as those
997 // aren't the ones picked by overload resolution.
998 if ((SS.isSet() || !BaseExpr ||
999 (isa<CXXThisExpr>(BaseExpr) &&
1000 cast<CXXThisExpr>(BaseExpr)->isImplicit())) &&
1001 !SuppressQualifierCheck &&
1002 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R))
1005 // Construct an unresolved result if we in fact got an unresolved
1007 if (R.isOverloadedResult() || R.isUnresolvableResult()) {
1008 // Suppress any lookup-related diagnostics; we'll do these when we
1010 R.suppressDiagnostics();
1012 UnresolvedMemberExpr *MemExpr
1013 = UnresolvedMemberExpr::Create(Context, R.isUnresolvableResult(),
1014 BaseExpr, BaseExprType,
1016 SS.getWithLocInContext(Context),
1017 TemplateKWLoc, MemberNameInfo,
1018 TemplateArgs, R.begin(), R.end());
1023 assert(R.isSingleResult());
1024 DeclAccessPair FoundDecl = R.begin().getPair();
1025 NamedDecl *MemberDecl = R.getFoundDecl();
1027 // FIXME: diagnose the presence of template arguments now.
1029 // If the decl being referenced had an error, return an error for this
1030 // sub-expr without emitting another error, in order to avoid cascading
1032 if (MemberDecl->isInvalidDecl())
1035 // Handle the implicit-member-access case.
1037 // If this is not an instance member, convert to a non-member access.
1038 if (!MemberDecl->isCXXInstanceMember())
1039 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), MemberDecl);
1041 SourceLocation Loc = R.getNameLoc();
1042 if (SS.getRange().isValid())
1043 Loc = SS.getRange().getBegin();
1044 CheckCXXThisCapture(Loc);
1045 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true);
1048 bool ShouldCheckUse = true;
1049 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) {
1050 // Don't diagnose the use of a virtual member function unless it's
1051 // explicitly qualified.
1052 if (MD->isVirtual() && !SS.isSet())
1053 ShouldCheckUse = false;
1056 // Check the use of this member.
1057 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc))
1060 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl))
1061 return BuildFieldReferenceExpr(*this, BaseExpr, IsArrow,
1062 SS, FD, FoundDecl, MemberNameInfo);
1064 if (MSPropertyDecl *PD = dyn_cast<MSPropertyDecl>(MemberDecl))
1065 return BuildMSPropertyRefExpr(*this, BaseExpr, IsArrow, SS, PD,
1068 if (IndirectFieldDecl *FD = dyn_cast<IndirectFieldDecl>(MemberDecl))
1069 // We may have found a field within an anonymous union or struct
1070 // (C++ [class.union]).
1071 return BuildAnonymousStructUnionMemberReference(SS, MemberLoc, FD,
1072 FoundDecl, BaseExpr,
1075 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) {
1076 return BuildMemberExpr(*this, Context, BaseExpr, IsArrow, SS, TemplateKWLoc,
1077 Var, FoundDecl, MemberNameInfo,
1078 Var->getType().getNonReferenceType(), VK_LValue,
1082 if (CXXMethodDecl *MemberFn = dyn_cast<CXXMethodDecl>(MemberDecl)) {
1083 ExprValueKind valueKind;
1085 if (MemberFn->isInstance()) {
1086 valueKind = VK_RValue;
1087 type = Context.BoundMemberTy;
1089 valueKind = VK_LValue;
1090 type = MemberFn->getType();
1093 return BuildMemberExpr(*this, Context, BaseExpr, IsArrow, SS, TemplateKWLoc,
1094 MemberFn, FoundDecl, MemberNameInfo, type, valueKind,
1097 assert(!isa<FunctionDecl>(MemberDecl) && "member function not C++ method?");
1099 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) {
1100 return BuildMemberExpr(*this, Context, BaseExpr, IsArrow, SS, TemplateKWLoc,
1101 Enum, FoundDecl, MemberNameInfo, Enum->getType(),
1102 VK_RValue, OK_Ordinary);
1105 // We found something that we didn't expect. Complain.
1106 if (isa<TypeDecl>(MemberDecl))
1107 Diag(MemberLoc, diag::err_typecheck_member_reference_type)
1108 << MemberName << BaseType << int(IsArrow);
1110 Diag(MemberLoc, diag::err_typecheck_member_reference_unknown)
1111 << MemberName << BaseType << int(IsArrow);
1113 Diag(MemberDecl->getLocation(), diag::note_member_declared_here)
1115 R.suppressDiagnostics();
1119 /// Given that normal member access failed on the given expression,
1120 /// and given that the expression's type involves builtin-id or
1121 /// builtin-Class, decide whether substituting in the redefinition
1122 /// types would be profitable. The redefinition type is whatever
1123 /// this translation unit tried to typedef to id/Class; we store
1124 /// it to the side and then re-use it in places like this.
1125 static bool ShouldTryAgainWithRedefinitionType(Sema &S, ExprResult &base) {
1126 const ObjCObjectPointerType *opty
1127 = base.get()->getType()->getAs<ObjCObjectPointerType>();
1128 if (!opty) return false;
1130 const ObjCObjectType *ty = opty->getObjectType();
1133 if (ty->isObjCId()) {
1134 redef = S.Context.getObjCIdRedefinitionType();
1135 } else if (ty->isObjCClass()) {
1136 redef = S.Context.getObjCClassRedefinitionType();
1141 // Do the substitution as long as the redefinition type isn't just a
1142 // possibly-qualified pointer to builtin-id or builtin-Class again.
1143 opty = redef->getAs<ObjCObjectPointerType>();
1144 if (opty && !opty->getObjectType()->getInterface())
1147 base = S.ImpCastExprToType(base.get(), redef, CK_BitCast);
1151 static bool isRecordType(QualType T) {
1152 return T->isRecordType();
1154 static bool isPointerToRecordType(QualType T) {
1155 if (const PointerType *PT = T->getAs<PointerType>())
1156 return PT->getPointeeType()->isRecordType();
1160 /// Perform conversions on the LHS of a member access expression.
1162 Sema::PerformMemberExprBaseConversion(Expr *Base, bool IsArrow) {
1163 if (IsArrow && !Base->getType()->isFunctionType())
1164 return DefaultFunctionArrayLvalueConversion(Base);
1166 return CheckPlaceholderExpr(Base);
1169 /// Look up the given member of the given non-type-dependent
1170 /// expression. This can return in one of two ways:
1171 /// * If it returns a sentinel null-but-valid result, the caller will
1172 /// assume that lookup was performed and the results written into
1173 /// the provided structure. It will take over from there.
1174 /// * Otherwise, the returned expression will be produced in place of
1175 /// an ordinary member expression.
1177 /// The ObjCImpDecl bit is a gross hack that will need to be properly
1178 /// fixed for ObjC++.
1179 static ExprResult LookupMemberExpr(Sema &S, LookupResult &R,
1180 ExprResult &BaseExpr, bool &IsArrow,
1181 SourceLocation OpLoc, CXXScopeSpec &SS,
1182 Decl *ObjCImpDecl, bool HasTemplateArgs) {
1183 assert(BaseExpr.get() && "no base expression");
1185 // Perform default conversions.
1186 BaseExpr = S.PerformMemberExprBaseConversion(BaseExpr.get(), IsArrow);
1187 if (BaseExpr.isInvalid())
1190 QualType BaseType = BaseExpr.get()->getType();
1191 assert(!BaseType->isDependentType());
1193 DeclarationName MemberName = R.getLookupName();
1194 SourceLocation MemberLoc = R.getNameLoc();
1196 // For later type-checking purposes, turn arrow accesses into dot
1197 // accesses. The only access type we support that doesn't follow
1198 // the C equivalence "a->b === (*a).b" is ObjC property accesses,
1199 // and those never use arrows, so this is unaffected.
1201 if (const PointerType *Ptr = BaseType->getAs<PointerType>())
1202 BaseType = Ptr->getPointeeType();
1203 else if (const ObjCObjectPointerType *Ptr
1204 = BaseType->getAs<ObjCObjectPointerType>())
1205 BaseType = Ptr->getPointeeType();
1206 else if (BaseType->isRecordType()) {
1207 // Recover from arrow accesses to records, e.g.:
1208 // struct MyRecord foo;
1210 // This is actually well-formed in C++ if MyRecord has an
1211 // overloaded operator->, but that should have been dealt with
1212 // by now--or a diagnostic message already issued if a problem
1213 // was encountered while looking for the overloaded operator->.
1214 if (!S.getLangOpts().CPlusPlus) {
1215 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
1216 << BaseType << int(IsArrow) << BaseExpr.get()->getSourceRange()
1217 << FixItHint::CreateReplacement(OpLoc, ".");
1220 } else if (BaseType->isFunctionType()) {
1223 S.Diag(MemberLoc, diag::err_typecheck_member_reference_arrow)
1224 << BaseType << BaseExpr.get()->getSourceRange();
1229 // Handle field access to simple records.
1230 if (const RecordType *RTy = BaseType->getAs<RecordType>()) {
1231 TypoExpr *TE = nullptr;
1232 if (LookupMemberExprInRecord(S, R, BaseExpr.get(), RTy,
1233 OpLoc, IsArrow, SS, HasTemplateArgs, TE))
1236 // Returning valid-but-null is how we indicate to the caller that
1237 // the lookup result was filled in. If typo correction was attempted and
1238 // failed, the lookup result will have been cleared--that combined with the
1239 // valid-but-null ExprResult will trigger the appropriate diagnostics.
1240 return ExprResult(TE);
1243 // Handle ivar access to Objective-C objects.
1244 if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>()) {
1245 if (!SS.isEmpty() && !SS.isInvalid()) {
1246 S.Diag(SS.getRange().getBegin(), diag::err_qualified_objc_access)
1247 << 1 << SS.getScopeRep()
1248 << FixItHint::CreateRemoval(SS.getRange());
1252 IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
1254 // There are three cases for the base type:
1255 // - builtin id (qualified or unqualified)
1256 // - builtin Class (qualified or unqualified)
1258 ObjCInterfaceDecl *IDecl = OTy->getInterface();
1260 if (S.getLangOpts().ObjCAutoRefCount &&
1261 (OTy->isObjCId() || OTy->isObjCClass()))
1263 // There's an implicit 'isa' ivar on all objects.
1264 // But we only actually find it this way on objects of type 'id',
1266 if (OTy->isObjCId() && Member->isStr("isa"))
1267 return new (S.Context) ObjCIsaExpr(BaseExpr.get(), IsArrow, MemberLoc,
1268 OpLoc, S.Context.getObjCClassType());
1269 if (ShouldTryAgainWithRedefinitionType(S, BaseExpr))
1270 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1271 ObjCImpDecl, HasTemplateArgs);
1275 if (S.RequireCompleteType(OpLoc, BaseType,
1276 diag::err_typecheck_incomplete_tag,
1280 ObjCInterfaceDecl *ClassDeclared = nullptr;
1281 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared);
1284 // Attempt to correct for typos in ivar names.
1285 auto Validator = llvm::make_unique<DeclFilterCCC<ObjCIvarDecl>>();
1286 Validator->IsObjCIvarLookup = IsArrow;
1287 if (TypoCorrection Corrected = S.CorrectTypo(
1288 R.getLookupNameInfo(), Sema::LookupMemberName, nullptr, nullptr,
1289 std::move(Validator), Sema::CTK_ErrorRecovery, IDecl)) {
1290 IV = Corrected.getCorrectionDeclAs<ObjCIvarDecl>();
1293 S.PDiag(diag::err_typecheck_member_reference_ivar_suggest)
1294 << IDecl->getDeclName() << MemberName);
1296 // Figure out the class that declares the ivar.
1297 assert(!ClassDeclared);
1298 Decl *D = cast<Decl>(IV->getDeclContext());
1299 if (ObjCCategoryDecl *CAT = dyn_cast<ObjCCategoryDecl>(D))
1300 D = CAT->getClassInterface();
1301 ClassDeclared = cast<ObjCInterfaceDecl>(D);
1303 if (IsArrow && IDecl->FindPropertyDeclaration(Member)) {
1304 S.Diag(MemberLoc, diag::err_property_found_suggest)
1305 << Member << BaseExpr.get()->getType()
1306 << FixItHint::CreateReplacement(OpLoc, ".");
1310 S.Diag(MemberLoc, diag::err_typecheck_member_reference_ivar)
1311 << IDecl->getDeclName() << MemberName
1312 << BaseExpr.get()->getSourceRange();
1317 assert(ClassDeclared);
1319 // If the decl being referenced had an error, return an error for this
1320 // sub-expr without emitting another error, in order to avoid cascading
1322 if (IV->isInvalidDecl())
1325 // Check whether we can reference this field.
1326 if (S.DiagnoseUseOfDecl(IV, MemberLoc))
1328 if (IV->getAccessControl() != ObjCIvarDecl::Public &&
1329 IV->getAccessControl() != ObjCIvarDecl::Package) {
1330 ObjCInterfaceDecl *ClassOfMethodDecl = nullptr;
1331 if (ObjCMethodDecl *MD = S.getCurMethodDecl())
1332 ClassOfMethodDecl = MD->getClassInterface();
1333 else if (ObjCImpDecl && S.getCurFunctionDecl()) {
1334 // Case of a c-function declared inside an objc implementation.
1335 // FIXME: For a c-style function nested inside an objc implementation
1336 // class, there is no implementation context available, so we pass
1337 // down the context as argument to this routine. Ideally, this context
1338 // need be passed down in the AST node and somehow calculated from the
1339 // AST for a function decl.
1340 if (ObjCImplementationDecl *IMPD =
1341 dyn_cast<ObjCImplementationDecl>(ObjCImpDecl))
1342 ClassOfMethodDecl = IMPD->getClassInterface();
1343 else if (ObjCCategoryImplDecl* CatImplClass =
1344 dyn_cast<ObjCCategoryImplDecl>(ObjCImpDecl))
1345 ClassOfMethodDecl = CatImplClass->getClassInterface();
1347 if (!S.getLangOpts().DebuggerSupport) {
1348 if (IV->getAccessControl() == ObjCIvarDecl::Private) {
1349 if (!declaresSameEntity(ClassDeclared, IDecl) ||
1350 !declaresSameEntity(ClassOfMethodDecl, ClassDeclared))
1351 S.Diag(MemberLoc, diag::error_private_ivar_access)
1352 << IV->getDeclName();
1353 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl))
1355 S.Diag(MemberLoc, diag::error_protected_ivar_access)
1356 << IV->getDeclName();
1360 if (S.getLangOpts().ObjCAutoRefCount) {
1361 Expr *BaseExp = BaseExpr.get()->IgnoreParenImpCasts();
1362 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(BaseExp))
1363 if (UO->getOpcode() == UO_Deref)
1364 BaseExp = UO->getSubExpr()->IgnoreParenCasts();
1366 if (DeclRefExpr *DE = dyn_cast<DeclRefExpr>(BaseExp))
1367 if (DE->getType().getObjCLifetime() == Qualifiers::OCL_Weak) {
1368 S.Diag(DE->getLocation(), diag::error_arc_weak_ivar_access);
1373 if (ObjCMethodDecl *MD = S.getCurMethodDecl()) {
1374 ObjCMethodFamily MF = MD->getMethodFamily();
1375 warn = (MF != OMF_init && MF != OMF_dealloc &&
1376 MF != OMF_finalize &&
1377 !S.IvarBacksCurrentMethodAccessor(IDecl, MD, IV));
1380 S.Diag(MemberLoc, diag::warn_direct_ivar_access) << IV->getDeclName();
1383 ObjCIvarRefExpr *Result = new (S.Context) ObjCIvarRefExpr(
1384 IV, IV->getType(), MemberLoc, OpLoc, BaseExpr.get(), IsArrow);
1386 if (S.getLangOpts().ObjCAutoRefCount) {
1387 if (IV->getType().getObjCLifetime() == Qualifiers::OCL_Weak) {
1388 if (!S.Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, MemberLoc))
1389 S.recordUseOfEvaluatedWeak(Result);
1396 // Objective-C property access.
1397 const ObjCObjectPointerType *OPT;
1398 if (!IsArrow && (OPT = BaseType->getAs<ObjCObjectPointerType>())) {
1399 if (!SS.isEmpty() && !SS.isInvalid()) {
1400 S.Diag(SS.getRange().getBegin(), diag::err_qualified_objc_access)
1401 << 0 << SS.getScopeRep() << FixItHint::CreateRemoval(SS.getRange());
1405 // This actually uses the base as an r-value.
1406 BaseExpr = S.DefaultLvalueConversion(BaseExpr.get());
1407 if (BaseExpr.isInvalid())
1410 assert(S.Context.hasSameUnqualifiedType(BaseType,
1411 BaseExpr.get()->getType()));
1413 IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
1415 const ObjCObjectType *OT = OPT->getObjectType();
1417 // id, with and without qualifiers.
1418 if (OT->isObjCId()) {
1419 // Check protocols on qualified interfaces.
1420 Selector Sel = S.PP.getSelectorTable().getNullarySelector(Member);
1422 FindGetterSetterNameDecl(OPT, Member, Sel, S.Context)) {
1423 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) {
1424 // Check the use of this declaration
1425 if (S.DiagnoseUseOfDecl(PD, MemberLoc))
1428 return new (S.Context)
1429 ObjCPropertyRefExpr(PD, S.Context.PseudoObjectTy, VK_LValue,
1430 OK_ObjCProperty, MemberLoc, BaseExpr.get());
1433 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) {
1434 // Check the use of this method.
1435 if (S.DiagnoseUseOfDecl(OMD, MemberLoc))
1437 Selector SetterSel =
1438 SelectorTable::constructSetterSelector(S.PP.getIdentifierTable(),
1439 S.PP.getSelectorTable(),
1441 ObjCMethodDecl *SMD = nullptr;
1442 if (Decl *SDecl = FindGetterSetterNameDecl(OPT,
1443 /*Property id*/ nullptr,
1444 SetterSel, S.Context))
1445 SMD = dyn_cast<ObjCMethodDecl>(SDecl);
1447 return new (S.Context)
1448 ObjCPropertyRefExpr(OMD, SMD, S.Context.PseudoObjectTy, VK_LValue,
1449 OK_ObjCProperty, MemberLoc, BaseExpr.get());
1452 // Use of id.member can only be for a property reference. Do not
1453 // use the 'id' redefinition in this case.
1454 if (IsArrow && ShouldTryAgainWithRedefinitionType(S, BaseExpr))
1455 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1456 ObjCImpDecl, HasTemplateArgs);
1458 return ExprError(S.Diag(MemberLoc, diag::err_property_not_found)
1459 << MemberName << BaseType);
1462 // 'Class', unqualified only.
1463 if (OT->isObjCClass()) {
1464 // Only works in a method declaration (??!).
1465 ObjCMethodDecl *MD = S.getCurMethodDecl();
1467 if (ShouldTryAgainWithRedefinitionType(S, BaseExpr))
1468 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1469 ObjCImpDecl, HasTemplateArgs);
1474 // Also must look for a getter name which uses property syntax.
1475 Selector Sel = S.PP.getSelectorTable().getNullarySelector(Member);
1476 ObjCInterfaceDecl *IFace = MD->getClassInterface();
1477 ObjCMethodDecl *Getter;
1478 if ((Getter = IFace->lookupClassMethod(Sel))) {
1479 // Check the use of this method.
1480 if (S.DiagnoseUseOfDecl(Getter, MemberLoc))
1483 Getter = IFace->lookupPrivateMethod(Sel, false);
1484 // If we found a getter then this may be a valid dot-reference, we
1485 // will look for the matching setter, in case it is needed.
1486 Selector SetterSel =
1487 SelectorTable::constructSetterSelector(S.PP.getIdentifierTable(),
1488 S.PP.getSelectorTable(),
1490 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel);
1492 // If this reference is in an @implementation, also check for 'private'
1494 Setter = IFace->lookupPrivateMethod(SetterSel, false);
1497 if (Setter && S.DiagnoseUseOfDecl(Setter, MemberLoc))
1500 if (Getter || Setter) {
1501 return new (S.Context) ObjCPropertyRefExpr(
1502 Getter, Setter, S.Context.PseudoObjectTy, VK_LValue,
1503 OK_ObjCProperty, MemberLoc, BaseExpr.get());
1506 if (ShouldTryAgainWithRedefinitionType(S, BaseExpr))
1507 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1508 ObjCImpDecl, HasTemplateArgs);
1510 return ExprError(S.Diag(MemberLoc, diag::err_property_not_found)
1511 << MemberName << BaseType);
1514 // Normal property access.
1515 return S.HandleExprPropertyRefExpr(OPT, BaseExpr.get(), OpLoc, MemberName,
1516 MemberLoc, SourceLocation(), QualType(),
1520 // Handle 'field access' to vectors, such as 'V.xx'.
1521 if (BaseType->isExtVectorType()) {
1522 // FIXME: this expr should store IsArrow.
1523 IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
1524 ExprValueKind VK = (IsArrow ? VK_LValue : BaseExpr.get()->getValueKind());
1525 QualType ret = CheckExtVectorComponent(S, BaseType, VK, OpLoc,
1530 return new (S.Context)
1531 ExtVectorElementExpr(ret, VK, BaseExpr.get(), *Member, MemberLoc);
1534 // Adjust builtin-sel to the appropriate redefinition type if that's
1535 // not just a pointer to builtin-sel again.
1536 if (IsArrow && BaseType->isSpecificBuiltinType(BuiltinType::ObjCSel) &&
1537 !S.Context.getObjCSelRedefinitionType()->isObjCSelType()) {
1538 BaseExpr = S.ImpCastExprToType(
1539 BaseExpr.get(), S.Context.getObjCSelRedefinitionType(), CK_BitCast);
1540 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1541 ObjCImpDecl, HasTemplateArgs);
1547 // Recover from dot accesses to pointers, e.g.:
1550 // This is actually well-formed in two cases:
1551 // - 'type' is an Objective C type
1552 // - 'bar' is a pseudo-destructor name which happens to refer to
1553 // the appropriate pointer type
1554 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) {
1555 if (!IsArrow && Ptr->getPointeeType()->isRecordType() &&
1556 MemberName.getNameKind() != DeclarationName::CXXDestructorName) {
1557 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
1558 << BaseType << int(IsArrow) << BaseExpr.get()->getSourceRange()
1559 << FixItHint::CreateReplacement(OpLoc, "->");
1561 // Recurse as an -> access.
1563 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1564 ObjCImpDecl, HasTemplateArgs);
1568 // If the user is trying to apply -> or . to a function name, it's probably
1569 // because they forgot parentheses to call that function.
1570 if (S.tryToRecoverWithCall(
1571 BaseExpr, S.PDiag(diag::err_member_reference_needs_call),
1573 IsArrow ? &isPointerToRecordType : &isRecordType)) {
1574 if (BaseExpr.isInvalid())
1576 BaseExpr = S.DefaultFunctionArrayConversion(BaseExpr.get());
1577 return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS,
1578 ObjCImpDecl, HasTemplateArgs);
1581 S.Diag(OpLoc, diag::err_typecheck_member_reference_struct_union)
1582 << BaseType << BaseExpr.get()->getSourceRange() << MemberLoc;
1587 /// The main callback when the parser finds something like
1588 /// expression . [nested-name-specifier] identifier
1589 /// expression -> [nested-name-specifier] identifier
1590 /// where 'identifier' encompasses a fairly broad spectrum of
1591 /// possibilities, including destructor and operator references.
1593 /// \param OpKind either tok::arrow or tok::period
1594 /// \param HasTrailingLParen whether the next token is '(', which
1595 /// is used to diagnose mis-uses of special members that can
1597 /// \param ObjCImpDecl the current Objective-C \@implementation
1598 /// decl; this is an ugly hack around the fact that Objective-C
1599 /// \@implementations aren't properly put in the context chain
1600 ExprResult Sema::ActOnMemberAccessExpr(Scope *S, Expr *Base,
1601 SourceLocation OpLoc,
1602 tok::TokenKind OpKind,
1604 SourceLocation TemplateKWLoc,
1607 bool HasTrailingLParen) {
1608 if (SS.isSet() && SS.isInvalid())
1611 // The only way a reference to a destructor can be used is to
1612 // immediately call it. If the next token is not a '(', produce
1613 // a diagnostic and build the call now.
1614 if (!HasTrailingLParen &&
1615 Id.getKind() == UnqualifiedId::IK_DestructorName) {
1616 ExprResult DtorAccess =
1617 ActOnMemberAccessExpr(S, Base, OpLoc, OpKind, SS, TemplateKWLoc, Id,
1618 ObjCImpDecl, /*HasTrailingLParen*/true);
1619 if (DtorAccess.isInvalid())
1621 return DiagnoseDtorReference(Id.getLocStart(), DtorAccess.get());
1624 // Warn about the explicit constructor calls Microsoft extension.
1625 if (getLangOpts().MicrosoftExt &&
1626 Id.getKind() == UnqualifiedId::IK_ConstructorName)
1627 Diag(Id.getSourceRange().getBegin(),
1628 diag::ext_ms_explicit_constructor_call);
1630 TemplateArgumentListInfo TemplateArgsBuffer;
1632 // Decompose the name into its component parts.
1633 DeclarationNameInfo NameInfo;
1634 const TemplateArgumentListInfo *TemplateArgs;
1635 DecomposeUnqualifiedId(Id, TemplateArgsBuffer,
1636 NameInfo, TemplateArgs);
1638 DeclarationName Name = NameInfo.getName();
1639 bool IsArrow = (OpKind == tok::arrow);
1641 NamedDecl *FirstQualifierInScope
1642 = (!SS.isSet() ? nullptr : FindFirstQualifierInScope(S, SS.getScopeRep()));
1644 // This is a postfix expression, so get rid of ParenListExprs.
1645 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base);
1646 if (Result.isInvalid()) return ExprError();
1647 Base = Result.get();
1649 if (Base->getType()->isDependentType() || Name.isDependentName() ||
1650 isDependentScopeSpecifier(SS)) {
1651 return ActOnDependentMemberExpr(Base, Base->getType(), IsArrow, OpLoc, SS,
1652 TemplateKWLoc, FirstQualifierInScope,
1653 NameInfo, TemplateArgs);
1656 ActOnMemberAccessExtraArgs ExtraArgs = {S, Id, ObjCImpDecl,
1658 return BuildMemberReferenceExpr(Base, Base->getType(), OpLoc, IsArrow, SS,
1659 TemplateKWLoc, FirstQualifierInScope,
1660 NameInfo, TemplateArgs, &ExtraArgs);
1664 BuildFieldReferenceExpr(Sema &S, Expr *BaseExpr, bool IsArrow,
1665 const CXXScopeSpec &SS, FieldDecl *Field,
1666 DeclAccessPair FoundDecl,
1667 const DeclarationNameInfo &MemberNameInfo) {
1668 // x.a is an l-value if 'a' has a reference type. Otherwise:
1669 // x.a is an l-value/x-value/pr-value if the base is (and note
1670 // that *x is always an l-value), except that if the base isn't
1671 // an ordinary object then we must have an rvalue.
1672 ExprValueKind VK = VK_LValue;
1673 ExprObjectKind OK = OK_Ordinary;
1675 if (BaseExpr->getObjectKind() == OK_Ordinary)
1676 VK = BaseExpr->getValueKind();
1680 if (VK != VK_RValue && Field->isBitField())
1683 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref]
1684 QualType MemberType = Field->getType();
1685 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) {
1686 MemberType = Ref->getPointeeType();
1689 QualType BaseType = BaseExpr->getType();
1690 if (IsArrow) BaseType = BaseType->getAs<PointerType>()->getPointeeType();
1692 Qualifiers BaseQuals = BaseType.getQualifiers();
1694 // GC attributes are never picked up by members.
1695 BaseQuals.removeObjCGCAttr();
1697 // CVR attributes from the base are picked up by members,
1698 // except that 'mutable' members don't pick up 'const'.
1699 if (Field->isMutable()) BaseQuals.removeConst();
1701 Qualifiers MemberQuals
1702 = S.Context.getCanonicalType(MemberType).getQualifiers();
1704 assert(!MemberQuals.hasAddressSpace());
1707 Qualifiers Combined = BaseQuals + MemberQuals;
1708 if (Combined != MemberQuals)
1709 MemberType = S.Context.getQualifiedType(MemberType, Combined);
1712 S.UnusedPrivateFields.remove(Field);
1715 S.PerformObjectMemberConversion(BaseExpr, SS.getScopeRep(),
1717 if (Base.isInvalid())
1719 return BuildMemberExpr(S, S.Context, Base.get(), IsArrow, SS,
1720 /*TemplateKWLoc=*/SourceLocation(), Field, FoundDecl,
1721 MemberNameInfo, MemberType, VK, OK);
1724 /// Builds an implicit member access expression. The current context
1725 /// is known to be an instance method, and the given unqualified lookup
1726 /// set is known to contain only instance members, at least one of which
1727 /// is from an appropriate type.
1729 Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS,
1730 SourceLocation TemplateKWLoc,
1732 const TemplateArgumentListInfo *TemplateArgs,
1733 bool IsKnownInstance) {
1734 assert(!R.empty() && !R.isAmbiguous());
1736 SourceLocation loc = R.getNameLoc();
1738 // If this is known to be an instance access, go ahead and build an
1739 // implicit 'this' expression now.
1740 // 'this' expression now.
1741 QualType ThisTy = getCurrentThisType();
1742 assert(!ThisTy.isNull() && "didn't correctly pre-flight capture of 'this'");
1744 Expr *baseExpr = nullptr; // null signifies implicit access
1745 if (IsKnownInstance) {
1746 SourceLocation Loc = R.getNameLoc();
1747 if (SS.getRange().isValid())
1748 Loc = SS.getRange().getBegin();
1749 CheckCXXThisCapture(Loc);
1750 baseExpr = new (Context) CXXThisExpr(loc, ThisTy, /*isImplicit=*/true);
1753 return BuildMemberReferenceExpr(baseExpr, ThisTy,
1754 /*OpLoc*/ SourceLocation(),
1757 /*FirstQualifierInScope*/ nullptr,