| //===--- SemaExprMember.cpp - Semantic Analysis for Expressions -----------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements semantic analysis member access expressions. |
| // |
| //===----------------------------------------------------------------------===// |
| #include "clang/Sema/Overload.h" |
| #include "clang/AST/ASTLambda.h" |
| #include "clang/AST/DeclCXX.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/DeclTemplate.h" |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/AST/ExprObjC.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "clang/Sema/Lookup.h" |
| #include "clang/Sema/Scope.h" |
| #include "clang/Sema/ScopeInfo.h" |
| #include "clang/Sema/SemaInternal.h" |
| |
| using namespace clang; |
| using namespace sema; |
| |
| typedef llvm::SmallPtrSet<const CXXRecordDecl*, 4> BaseSet; |
| |
| /// Determines if the given class is provably not derived from all of |
| /// the prospective base classes. |
| static bool isProvablyNotDerivedFrom(Sema &SemaRef, CXXRecordDecl *Record, |
| const BaseSet &Bases) { |
| auto BaseIsNotInSet = [&Bases](const CXXRecordDecl *Base) { |
| return !Bases.count(Base->getCanonicalDecl()); |
| }; |
| return BaseIsNotInSet(Record) && Record->forallBases(BaseIsNotInSet); |
| } |
| |
| enum IMAKind { |
| /// The reference is definitely not an instance member access. |
| IMA_Static, |
| |
| /// The reference may be an implicit instance member access. |
| IMA_Mixed, |
| |
| /// The reference may be to an instance member, but it might be invalid if |
| /// so, because the context is not an instance method. |
| IMA_Mixed_StaticContext, |
| |
| /// The reference may be to an instance member, but it is invalid if |
| /// so, because the context is from an unrelated class. |
| IMA_Mixed_Unrelated, |
| |
| /// The reference is definitely an implicit instance member access. |
| IMA_Instance, |
| |
| /// The reference may be to an unresolved using declaration. |
| IMA_Unresolved, |
| |
| /// The reference is a contextually-permitted abstract member reference. |
| IMA_Abstract, |
| |
| /// The reference may be to an unresolved using declaration and the |
| /// context is not an instance method. |
| IMA_Unresolved_StaticContext, |
| |
| // The reference refers to a field which is not a member of the containing |
| // class, which is allowed because we're in C++11 mode and the context is |
| // unevaluated. |
| IMA_Field_Uneval_Context, |
| |
| /// All possible referrents are instance members and the current |
| /// context is not an instance method. |
| IMA_Error_StaticContext, |
| |
| /// All possible referrents are instance members of an unrelated |
| /// class. |
| IMA_Error_Unrelated |
| }; |
| |
| /// The given lookup names class member(s) and is not being used for |
| /// an address-of-member expression. Classify the type of access |
| /// according to whether it's possible that this reference names an |
| /// instance member. This is best-effort in dependent contexts; it is okay to |
| /// conservatively answer "yes", in which case some errors will simply |
| /// not be caught until template-instantiation. |
| static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, |
| const LookupResult &R) { |
| assert(!R.empty() && (*R.begin())->isCXXClassMember()); |
| |
| DeclContext *DC = SemaRef.getFunctionLevelDeclContext(); |
| |
| bool isStaticContext = SemaRef.CXXThisTypeOverride.isNull() && |
| (!isa<CXXMethodDecl>(DC) || cast<CXXMethodDecl>(DC)->isStatic()); |
| |
| if (R.isUnresolvableResult()) |
| return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; |
| |
| // Collect all the declaring classes of instance members we find. |
| bool hasNonInstance = false; |
| bool isField = false; |
| BaseSet Classes; |
| for (NamedDecl *D : R) { |
| // Look through any using decls. |
| D = D->getUnderlyingDecl(); |
| |
| if (D->isCXXInstanceMember()) { |
| isField |= isa<FieldDecl>(D) || isa<MSPropertyDecl>(D) || |
| isa<IndirectFieldDecl>(D); |
| |
| CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); |
| Classes.insert(R->getCanonicalDecl()); |
| } else |
| hasNonInstance = true; |
| } |
| |
| // If we didn't find any instance members, it can't be an implicit |
| // member reference. |
| if (Classes.empty()) |
| return IMA_Static; |
| |
| // C++11 [expr.prim.general]p12: |
| // An id-expression that denotes a non-static data member or non-static |
| // member function of a class can only be used: |
| // (...) |
| // - if that id-expression denotes a non-static data member and it |
| // appears in an unevaluated operand. |
| // |
| // This rule is specific to C++11. However, we also permit this form |
| // in unevaluated inline assembly operands, like the operand to a SIZE. |
| IMAKind AbstractInstanceResult = IMA_Static; // happens to be 'false' |
| assert(!AbstractInstanceResult); |
| switch (SemaRef.ExprEvalContexts.back().Context) { |
| case Sema::ExpressionEvaluationContext::Unevaluated: |
| case Sema::ExpressionEvaluationContext::UnevaluatedList: |
| if (isField && SemaRef.getLangOpts().CPlusPlus11) |
| AbstractInstanceResult = IMA_Field_Uneval_Context; |
| break; |
| |
| case Sema::ExpressionEvaluationContext::UnevaluatedAbstract: |
| AbstractInstanceResult = IMA_Abstract; |
| break; |
| |
| case Sema::ExpressionEvaluationContext::DiscardedStatement: |
| case Sema::ExpressionEvaluationContext::ConstantEvaluated: |
| case Sema::ExpressionEvaluationContext::ImmediateFunctionContext: |
| case Sema::ExpressionEvaluationContext::PotentiallyEvaluated: |
| case Sema::ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed: |
| break; |
| } |
| |
| // If the current context is not an instance method, it can't be |
| // an implicit member reference. |
| if (isStaticContext) { |
| if (hasNonInstance) |
| return IMA_Mixed_StaticContext; |
| |
| return AbstractInstanceResult ? AbstractInstanceResult |
| : IMA_Error_StaticContext; |
| } |
| |
| CXXRecordDecl *contextClass; |
| if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) |
| contextClass = MD->getParent()->getCanonicalDecl(); |
| else |
| contextClass = cast<CXXRecordDecl>(DC); |
| |
| // [class.mfct.non-static]p3: |
| // ...is used in the body of a non-static member function of class X, |
| // if name lookup (3.4.1) resolves the name in the id-expression to a |
| // non-static non-type member of some class C [...] |
| // ...if C is not X or a base class of X, the class member access expression |
| // is ill-formed. |
| if (R.getNamingClass() && |
| contextClass->getCanonicalDecl() != |
| R.getNamingClass()->getCanonicalDecl()) { |
| // If the naming class is not the current context, this was a qualified |
| // member name lookup, and it's sufficient to check that we have the naming |
| // class as a base class. |
| Classes.clear(); |
| Classes.insert(R.getNamingClass()->getCanonicalDecl()); |
| } |
| |
| // If we can prove that the current context is unrelated to all the |
| // declaring classes, it can't be an implicit member reference (in |
| // which case it's an error if any of those members are selected). |
| if (isProvablyNotDerivedFrom(SemaRef, contextClass, Classes)) |
| return hasNonInstance ? IMA_Mixed_Unrelated : |
| AbstractInstanceResult ? AbstractInstanceResult : |
| IMA_Error_Unrelated; |
| |
| return (hasNonInstance ? IMA_Mixed : IMA_Instance); |
| } |
| |
| /// Diagnose a reference to a field with no object available. |
| static void diagnoseInstanceReference(Sema &SemaRef, |
| const CXXScopeSpec &SS, |
| NamedDecl *Rep, |
| const DeclarationNameInfo &nameInfo) { |
| SourceLocation Loc = nameInfo.getLoc(); |
| SourceRange Range(Loc); |
| if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); |
| |
| // Look through using shadow decls and aliases. |
| Rep = Rep->getUnderlyingDecl(); |
| |
| DeclContext *FunctionLevelDC = SemaRef.getFunctionLevelDeclContext(); |
| CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FunctionLevelDC); |
| CXXRecordDecl *ContextClass = Method ? Method->getParent() : nullptr; |
| CXXRecordDecl *RepClass = dyn_cast<CXXRecordDecl>(Rep->getDeclContext()); |
| |
| bool InStaticMethod = Method && Method->isStatic(); |
| bool IsField = isa<FieldDecl>(Rep) || isa<IndirectFieldDecl>(Rep); |
| |
| if (IsField && InStaticMethod) |
| // "invalid use of member 'x' in static member function" |
| SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) |
| << Range << nameInfo.getName(); |
| else if (ContextClass && RepClass && SS.isEmpty() && !InStaticMethod && |
| !RepClass->Equals(ContextClass) && RepClass->Encloses(ContextClass)) |
| // Unqualified lookup in a non-static member function found a member of an |
| // enclosing class. |
| SemaRef.Diag(Loc, diag::err_nested_non_static_member_use) |
| << IsField << RepClass << nameInfo.getName() << ContextClass << Range; |
| else if (IsField) |
| SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) |
| << nameInfo.getName() << Range; |
| else |
| SemaRef.Diag(Loc, diag::err_member_call_without_object) |
| << Range; |
| } |
| |
| /// Builds an expression which might be an implicit member expression. |
| ExprResult Sema::BuildPossibleImplicitMemberExpr( |
| const CXXScopeSpec &SS, SourceLocation TemplateKWLoc, LookupResult &R, |
| const TemplateArgumentListInfo *TemplateArgs, const Scope *S, |
| UnresolvedLookupExpr *AsULE) { |
| switch (ClassifyImplicitMemberAccess(*this, R)) { |
| case IMA_Instance: |
| return BuildImplicitMemberExpr(SS, TemplateKWLoc, R, TemplateArgs, true, S); |
| |
| case IMA_Mixed: |
| case IMA_Mixed_Unrelated: |
| case IMA_Unresolved: |
| return BuildImplicitMemberExpr(SS, TemplateKWLoc, R, TemplateArgs, false, |
| S); |
| |
| case IMA_Field_Uneval_Context: |
| Diag(R.getNameLoc(), diag::warn_cxx98_compat_non_static_member_use) |
| << R.getLookupNameInfo().getName(); |
| LLVM_FALLTHROUGH; |
| case IMA_Static: |
| case IMA_Abstract: |
| case IMA_Mixed_StaticContext: |
| case IMA_Unresolved_StaticContext: |
| if (TemplateArgs || TemplateKWLoc.isValid()) |
| return BuildTemplateIdExpr(SS, TemplateKWLoc, R, false, TemplateArgs); |
| return AsULE ? AsULE : BuildDeclarationNameExpr(SS, R, false); |
| |
| case IMA_Error_StaticContext: |
| case IMA_Error_Unrelated: |
| diagnoseInstanceReference(*this, SS, R.getRepresentativeDecl(), |
| R.getLookupNameInfo()); |
| return ExprError(); |
| } |
| |
| llvm_unreachable("unexpected instance member access kind"); |
| } |
| |
| /// Determine whether input char is from rgba component set. |
| static bool |
| IsRGBA(char c) { |
| switch (c) { |
| case 'r': |
| case 'g': |
| case 'b': |
| case 'a': |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| // OpenCL v1.1, s6.1.7 |
| // The component swizzle length must be in accordance with the acceptable |
| // vector sizes. |
| static bool IsValidOpenCLComponentSwizzleLength(unsigned len) |
| { |
| return (len >= 1 && len <= 4) || len == 8 || len == 16; |
| } |
| |
| /// Check an ext-vector component access expression. |
| /// |
| /// VK should be set in advance to the value kind of the base |
| /// expression. |
| static QualType |
| CheckExtVectorComponent(Sema &S, QualType baseType, ExprValueKind &VK, |
| SourceLocation OpLoc, const IdentifierInfo *CompName, |
| SourceLocation CompLoc) { |
| // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, |
| // see FIXME there. |
| // |
| // FIXME: This logic can be greatly simplified by splitting it along |
| // halving/not halving and reworking the component checking. |
| const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); |
| |
| // The vector accessor can't exceed the number of elements. |
| const char *compStr = CompName->getNameStart(); |
| |
| // This flag determines whether or not the component is one of the four |
| // special names that indicate a subset of exactly half the elements are |
| // to be selected. |
| bool HalvingSwizzle = false; |
| |
| // This flag determines whether or not CompName has an 's' char prefix, |
| // indicating that it is a string of hex values to be used as vector indices. |
| bool HexSwizzle = (*compStr == 's' || *compStr == 'S') && compStr[1]; |
| |
| bool HasRepeated = false; |
| bool HasIndex[16] = {}; |
| |
| int Idx; |
| |
| // Check that we've found one of the special components, or that the component |
| // names must come from the same set. |
| if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || |
| !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { |
| HalvingSwizzle = true; |
| } else if (!HexSwizzle && |
| (Idx = vecType->getPointAccessorIdx(*compStr)) != -1) { |
| bool HasRGBA = IsRGBA(*compStr); |
| do { |
| // Ensure that xyzw and rgba components don't intermingle. |
| if (HasRGBA != IsRGBA(*compStr)) |
| break; |
| if (HasIndex[Idx]) HasRepeated = true; |
| HasIndex[Idx] = true; |
| compStr++; |
| } while (*compStr && (Idx = vecType->getPointAccessorIdx(*compStr)) != -1); |
| |
| // Emit a warning if an rgba selector is used earlier than OpenCL C 3.0. |
| if (HasRGBA || (*compStr && IsRGBA(*compStr))) { |
| if (S.getLangOpts().OpenCL && |
| S.getLangOpts().getOpenCLCompatibleVersion() < 300) { |
| const char *DiagBegin = HasRGBA ? CompName->getNameStart() : compStr; |
| S.Diag(OpLoc, diag::ext_opencl_ext_vector_type_rgba_selector) |
| << StringRef(DiagBegin, 1) << SourceRange(CompLoc); |
| } |
| } |
| } else { |
| if (HexSwizzle) compStr++; |
| while ((Idx = vecType->getNumericAccessorIdx(*compStr)) != -1) { |
| if (HasIndex[Idx]) HasRepeated = true; |
| HasIndex[Idx] = true; |
| compStr++; |
| } |
| } |
| |
| if (!HalvingSwizzle && *compStr) { |
| // We didn't get to the end of the string. This means the component names |
| // didn't come from the same set *or* we encountered an illegal name. |
| S.Diag(OpLoc, diag::err_ext_vector_component_name_illegal) |
| << StringRef(compStr, 1) << SourceRange(CompLoc); |
| return QualType(); |
| } |
| |
| // Ensure no component accessor exceeds the width of the vector type it |
| // operates on. |
| if (!HalvingSwizzle) { |
| compStr = CompName->getNameStart(); |
| |
| if (HexSwizzle) |
| compStr++; |
| |
| while (*compStr) { |
| if (!vecType->isAccessorWithinNumElements(*compStr++, HexSwizzle)) { |
| S.Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) |
| << baseType << SourceRange(CompLoc); |
| return QualType(); |
| } |
| } |
| } |
| |
| // OpenCL mode requires swizzle length to be in accordance with accepted |
| // sizes. Clang however supports arbitrary lengths for other languages. |
| if (S.getLangOpts().OpenCL && !HalvingSwizzle) { |
| unsigned SwizzleLength = CompName->getLength(); |
| |
| if (HexSwizzle) |
| SwizzleLength--; |
| |
| if (IsValidOpenCLComponentSwizzleLength(SwizzleLength) == false) { |
| S.Diag(OpLoc, diag::err_opencl_ext_vector_component_invalid_length) |
| << SwizzleLength << SourceRange(CompLoc); |
| return QualType(); |
| } |
| } |
| |
| // The component accessor looks fine - now we need to compute the actual type. |
| // The vector type is implied by the component accessor. For example, |
| // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. |
| // vec4.s0 is a float, vec4.s23 is a vec3, etc. |
| // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. |
| unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 |
| : CompName->getLength(); |
| if (HexSwizzle) |
| CompSize--; |
| |
| if (CompSize == 1) |
| return vecType->getElementType(); |
| |
| if (HasRepeated) |
| VK = VK_PRValue; |
| |
| QualType VT = S.Context.getExtVectorType(vecType->getElementType(), CompSize); |
| // Now look up the TypeDefDecl from the vector type. Without this, |
| // diagostics look bad. We want extended vector types to appear built-in. |
| for (Sema::ExtVectorDeclsType::iterator |
| I = S.ExtVectorDecls.begin(S.getExternalSource()), |
| E = S.ExtVectorDecls.end(); |
| I != E; ++I) { |
| if ((*I)->getUnderlyingType() == VT) |
| return S.Context.getTypedefType(*I); |
| } |
| |
| return VT; // should never get here (a typedef type should always be found). |
| } |
| |
| static Decl *FindGetterSetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, |
| IdentifierInfo *Member, |
| const Selector &Sel, |
| ASTContext &Context) { |
| if (Member) |
| if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration( |
| Member, ObjCPropertyQueryKind::OBJC_PR_query_instance)) |
| return PD; |
| if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) |
| return OMD; |
| |
| for (const auto *I : PDecl->protocols()) { |
| if (Decl *D = FindGetterSetterNameDeclFromProtocolList(I, Member, Sel, |
| Context)) |
| return D; |
| } |
| return nullptr; |
| } |
| |
| static Decl *FindGetterSetterNameDecl(const ObjCObjectPointerType *QIdTy, |
| IdentifierInfo *Member, |
| const Selector &Sel, |
| ASTContext &Context) { |
| // Check protocols on qualified interfaces. |
| Decl *GDecl = nullptr; |
| for (const auto *I : QIdTy->quals()) { |
| if (Member) |
| if (ObjCPropertyDecl *PD = I->FindPropertyDeclaration( |
| Member, ObjCPropertyQueryKind::OBJC_PR_query_instance)) { |
| GDecl = PD; |
| break; |
| } |
| // Also must look for a getter or setter name which uses property syntax. |
| if (ObjCMethodDecl *OMD = I->getInstanceMethod(Sel)) { |
| GDecl = OMD; |
| break; |
| } |
| } |
| if (!GDecl) { |
| for (const auto *I : QIdTy->quals()) { |
| // Search in the protocol-qualifier list of current protocol. |
| GDecl = FindGetterSetterNameDeclFromProtocolList(I, Member, Sel, Context); |
| if (GDecl) |
| return GDecl; |
| } |
| } |
| return GDecl; |
| } |
| |
| ExprResult |
| Sema::ActOnDependentMemberExpr(Expr *BaseExpr, QualType BaseType, |
| bool IsArrow, SourceLocation OpLoc, |
| const CXXScopeSpec &SS, |
| SourceLocation TemplateKWLoc, |
| NamedDecl *FirstQualifierInScope, |
| const DeclarationNameInfo &NameInfo, |
| const TemplateArgumentListInfo *TemplateArgs) { |
| // Even in dependent contexts, try to diagnose base expressions with |
| // obviously wrong types, e.g.: |
| // |
| // T* t; |
| // t.f; |
| // |
| // In Obj-C++, however, the above expression is valid, since it could be |
| // accessing the 'f' property if T is an Obj-C interface. The extra check |
| // allows this, while still reporting an error if T is a struct pointer. |
| if (!IsArrow) { |
| const PointerType *PT = BaseType->getAs<PointerType>(); |
| if (PT && (!getLangOpts().ObjC || |
| PT->getPointeeType()->isRecordType())) { |
| assert(BaseExpr && "cannot happen with implicit member accesses"); |
| Diag(OpLoc, diag::err_typecheck_member_reference_struct_union) |
| << BaseType << BaseExpr->getSourceRange() << NameInfo.getSourceRange(); |
| return ExprError(); |
| } |
| } |
| |
| assert(BaseType->isDependentType() || |
| NameInfo.getName().isDependentName() || |
| isDependentScopeSpecifier(SS)); |
| |
| // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr |
| // must have pointer type, and the accessed type is the pointee. |
| return CXXDependentScopeMemberExpr::Create( |
| Context, BaseExpr, BaseType, IsArrow, OpLoc, |
| SS.getWithLocInContext(Context), TemplateKWLoc, FirstQualifierInScope, |
| NameInfo, TemplateArgs); |
| } |
| |
| /// We know that the given qualified member reference points only to |
| /// declarations which do not belong to the static type of the base |
| /// expression. Diagnose the problem. |
| static void DiagnoseQualifiedMemberReference(Sema &SemaRef, |
| Expr *BaseExpr, |
| QualType BaseType, |
| const CXXScopeSpec &SS, |
| NamedDecl *rep, |
| const DeclarationNameInfo &nameInfo) { |
| // If this is an implicit member access, use a different set of |
| // diagnostics. |
| if (!BaseExpr) |
| return diagnoseInstanceReference(SemaRef, SS, rep, nameInfo); |
| |
| SemaRef.Diag(nameInfo.getLoc(), diag::err_qualified_member_of_unrelated) |
| << SS.getRange() << rep << BaseType; |
| } |
| |
| // Check whether the declarations we found through a nested-name |
| // specifier in a member expression are actually members of the base |
| // type. The restriction here is: |
| // |
| // C++ [expr.ref]p2: |
| // ... In these cases, the id-expression shall name a |
| // member of the class or of one of its base classes. |
| // |
| // So it's perfectly legitimate for the nested-name specifier to name |
| // an unrelated class, and for us to find an overload set including |
| // decls from classes which are not superclasses, as long as the decl |
| // we actually pick through overload resolution is from a superclass. |
| bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, |
| QualType BaseType, |
| const CXXScopeSpec &SS, |
| const LookupResult &R) { |
| CXXRecordDecl *BaseRecord = |
| cast_or_null<CXXRecordDecl>(computeDeclContext(BaseType)); |
| if (!BaseRecord) { |
| // We can't check this yet because the base type is still |
| // dependent. |
| assert(BaseType->isDependentType()); |
| return false; |
| } |
| |
| for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { |
| // If this is an implicit member reference and we find a |
| // non-instance member, it's not an error. |
| if (!BaseExpr && !(*I)->isCXXInstanceMember()) |
| return false; |
| |
| // Note that we use the DC of the decl, not the underlying decl. |
| DeclContext *DC = (*I)->getDeclContext()->getNonTransparentContext(); |
| if (!DC->isRecord()) |
| continue; |
| |
| CXXRecordDecl *MemberRecord = cast<CXXRecordDecl>(DC)->getCanonicalDecl(); |
| if (BaseRecord->getCanonicalDecl() == MemberRecord || |
| !BaseRecord->isProvablyNotDerivedFrom(MemberRecord)) |
| return false; |
| } |
| |
| DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, |
| R.getRepresentativeDecl(), |
| R.getLookupNameInfo()); |
| return true; |
| } |
| |
| namespace { |
| |
| // Callback to only accept typo corrections that are either a ValueDecl or a |
| // FunctionTemplateDecl and are declared in the current record or, for a C++ |
| // classes, one of its base classes. |
| class RecordMemberExprValidatorCCC final : public CorrectionCandidateCallback { |
| public: |
| explicit RecordMemberExprValidatorCCC(const RecordType *RTy) |
| : Record(RTy->getDecl()) { |
| // Don't add bare keywords to the consumer since they will always fail |
| // validation by virtue of not being associated with any decls. |
| WantTypeSpecifiers = false; |
| WantExpressionKeywords = false; |
| WantCXXNamedCasts = false; |
| WantFunctionLikeCasts = false; |
| WantRemainingKeywords = false; |
| } |
| |
| bool ValidateCandidate(const TypoCorrection &candidate) override { |
| NamedDecl *ND = candidate.getCorrectionDecl(); |
| // Don't accept candidates that cannot be member functions, constants, |
| // variables, or templates. |
| if (!ND || !(isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND))) |
| return false; |
| |
| // Accept candidates that occur in the current record. |
| if (Record->containsDecl(ND)) |
| return true; |
| |
| if (const auto *RD = dyn_cast<CXXRecordDecl>(Record)) { |
| // Accept candidates that occur in any of the current class' base classes. |
| for (const auto &BS : RD->bases()) { |
| if (const auto *BSTy = BS.getType()->getAs<RecordType>()) { |
| if (BSTy->getDecl()->containsDecl(ND)) |
| return true; |
| } |
| } |
| } |
| |
| return false; |
| } |
| |
| std::unique_ptr<CorrectionCandidateCallback> clone() override { |
| return std::make_unique<RecordMemberExprValidatorCCC>(*this); |
| } |
| |
| private: |
| const RecordDecl *const Record; |
| }; |
| |
| } |
| |
| static bool LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, |
| Expr *BaseExpr, |
| const RecordType *RTy, |
| SourceLocation OpLoc, bool IsArrow, |
| CXXScopeSpec &SS, bool HasTemplateArgs, |
| SourceLocation TemplateKWLoc, |
| TypoExpr *&TE) { |
| SourceRange BaseRange = BaseExpr ? BaseExpr->getSourceRange() : SourceRange(); |
| RecordDecl *RDecl = RTy->getDecl(); |
| if (!SemaRef.isThisOutsideMemberFunctionBody(QualType(RTy, 0)) && |
| SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), |
| diag::err_typecheck_incomplete_tag, |
| BaseRange)) |
| return true; |
| |
| if (HasTemplateArgs || TemplateKWLoc.isValid()) { |
| // LookupTemplateName doesn't expect these both to exist simultaneously. |
| QualType ObjectType = SS.isSet() ? QualType() : QualType(RTy, 0); |
| |
| bool MOUS; |
| return SemaRef.LookupTemplateName(R, nullptr, SS, ObjectType, false, MOUS, |
| TemplateKWLoc); |
| } |
| |
| DeclContext *DC = RDecl; |
| if (SS.isSet()) { |
| // If the member name was a qualified-id, look into the |
| // nested-name-specifier. |
| DC = SemaRef.computeDeclContext(SS, false); |
| |
| if (SemaRef.RequireCompleteDeclContext(SS, DC)) { |
| SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) |
| << SS.getRange() << DC; |
| return true; |
| } |
| |
| assert(DC && "Cannot handle non-computable dependent contexts in lookup"); |
| |
| if (!isa<TypeDecl>(DC)) { |
| SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) |
| << DC << SS.getRange(); |
| return true; |
| } |
| } |
| |
| // The record definition is complete, now look up the member. |
| SemaRef.LookupQualifiedName(R, DC, SS); |
| |
| if (!R.empty()) |
| return false; |
| |
| DeclarationName Typo = R.getLookupName(); |
| SourceLocation TypoLoc = R.getNameLoc(); |
| |
| struct QueryState { |
| Sema &SemaRef; |
| DeclarationNameInfo NameInfo; |
| Sema::LookupNameKind LookupKind; |
| Sema::RedeclarationKind Redecl; |
| }; |
| QueryState Q = {R.getSema(), R.getLookupNameInfo(), R.getLookupKind(), |
| R.redeclarationKind()}; |
| RecordMemberExprValidatorCCC CCC(RTy); |
| TE = SemaRef.CorrectTypoDelayed( |
| R.getLookupNameInfo(), R.getLookupKind(), nullptr, &SS, CCC, |
| [=, &SemaRef](const TypoCorrection &TC) { |
| if (TC) { |
| assert(!TC.isKeyword() && |
| "Got a keyword as a correction for a member!"); |
| bool DroppedSpecifier = |
| TC.WillReplaceSpecifier() && |
| Typo.getAsString() == TC.getAsString(SemaRef.getLangOpts()); |
| SemaRef.diagnoseTypo(TC, SemaRef.PDiag(diag::err_no_member_suggest) |
| << Typo << DC << DroppedSpecifier |
| << SS.getRange()); |
| } else { |
| SemaRef.Diag(TypoLoc, diag::err_no_member) << Typo << DC << BaseRange; |
| } |
| }, |
| [=](Sema &SemaRef, TypoExpr *TE, TypoCorrection TC) mutable { |
| LookupResult R(Q.SemaRef, Q.NameInfo, Q.LookupKind, Q.Redecl); |
| R.clear(); // Ensure there's no decls lingering in the shared state. |
| R.suppressDiagnostics(); |
| R.setLookupName(TC.getCorrection()); |
| for (NamedDecl *ND : TC) |
| R.addDecl(ND); |
| R.resolveKind(); |
| return SemaRef.BuildMemberReferenceExpr( |
| BaseExpr, BaseExpr->getType(), OpLoc, IsArrow, SS, SourceLocation(), |
| nullptr, R, nullptr, nullptr); |
| }, |
| Sema::CTK_ErrorRecovery, DC); |
| |
| return false; |
| } |
| |
| static ExprResult LookupMemberExpr(Sema &S, LookupResult &R, |
| ExprResult &BaseExpr, bool &IsArrow, |
| SourceLocation OpLoc, CXXScopeSpec &SS, |
| Decl *ObjCImpDecl, bool HasTemplateArgs, |
| SourceLocation TemplateKWLoc); |
| |
| ExprResult |
| Sema::BuildMemberReferenceExpr(Expr *Base, QualType BaseType, |
| SourceLocation OpLoc, bool IsArrow, |
| CXXScopeSpec &SS, |
| SourceLocation TemplateKWLoc, |
| NamedDecl *FirstQualifierInScope, |
| const DeclarationNameInfo &NameInfo, |
| const TemplateArgumentListInfo *TemplateArgs, |
| const Scope *S, |
| ActOnMemberAccessExtraArgs *ExtraArgs) { |
| if (BaseType->isDependentType() || |
| (SS.isSet() && isDependentScopeSpecifier(SS))) |
| return ActOnDependentMemberExpr(Base, BaseType, |
| IsArrow, OpLoc, |
| SS, TemplateKWLoc, FirstQualifierInScope, |
| NameInfo, TemplateArgs); |
| |
| LookupResult R(*this, NameInfo, LookupMemberName); |
| |
| // Implicit member accesses. |
| if (!Base) { |
| TypoExpr *TE = nullptr; |
| QualType RecordTy = BaseType; |
| if (IsArrow) RecordTy = RecordTy->castAs<PointerType>()->getPointeeType(); |
| if (LookupMemberExprInRecord( |
| *this, R, nullptr, RecordTy->getAs<RecordType>(), OpLoc, IsArrow, |
| SS, TemplateArgs != nullptr, TemplateKWLoc, TE)) |
| return ExprError(); |
| if (TE) |
| return TE; |
| |
| // Explicit member accesses. |
| } else { |
| ExprResult BaseResult = Base; |
| ExprResult Result = |
| LookupMemberExpr(*this, R, BaseResult, IsArrow, OpLoc, SS, |
| ExtraArgs ? ExtraArgs->ObjCImpDecl : nullptr, |
| TemplateArgs != nullptr, TemplateKWLoc); |
| |
| if (BaseResult.isInvalid()) |
| return ExprError(); |
| Base = BaseResult.get(); |
| |
| if (Result.isInvalid()) |
| return ExprError(); |
| |
| if (Result.get()) |
| return Result; |
| |
| // LookupMemberExpr can modify Base, and thus change BaseType |
| BaseType = Base->getType(); |
| } |
| |
| return BuildMemberReferenceExpr(Base, BaseType, |
| OpLoc, IsArrow, SS, TemplateKWLoc, |
| FirstQualifierInScope, R, TemplateArgs, S, |
| false, ExtraArgs); |
| } |
| |
| ExprResult |
| Sema::BuildAnonymousStructUnionMemberReference(const CXXScopeSpec &SS, |
| SourceLocation loc, |
| IndirectFieldDecl *indirectField, |
| DeclAccessPair foundDecl, |
| Expr *baseObjectExpr, |
| SourceLocation opLoc) { |
| // First, build the expression that refers to the base object. |
| |
| // Case 1: the base of the indirect field is not a field. |
| VarDecl *baseVariable = indirectField->getVarDecl(); |
| CXXScopeSpec EmptySS; |
| if (baseVariable) { |
| assert(baseVariable->getType()->isRecordType()); |
| |
| // In principle we could have a member access expression that |
| // accesses an anonymous struct/union that's a static member of |
| // the base object's class. However, under the current standard, |
| // static data members cannot be anonymous structs or unions. |
| // Supporting this is as easy as building a MemberExpr here. |
| assert(!baseObjectExpr && "anonymous struct/union is static data member?"); |
| |
| DeclarationNameInfo baseNameInfo(DeclarationName(), loc); |
| |
| ExprResult result |
| = BuildDeclarationNameExpr(EmptySS, baseNameInfo, baseVariable); |
| if (result.isInvalid()) return ExprError(); |
| |
| baseObjectExpr = result.get(); |
| } |
| |
| assert((baseVariable || baseObjectExpr) && |
| "referencing anonymous struct/union without a base variable or " |
| "expression"); |
| |
| // Build the implicit member references to the field of the |
| // anonymous struct/union. |
| Expr *result = baseObjectExpr; |
| IndirectFieldDecl::chain_iterator |
| FI = indirectField->chain_begin(), FEnd = indirectField->chain_end(); |
| |
| // Case 2: the base of the indirect field is a field and the user |
| // wrote a member expression. |
| if (!baseVariable) { |
| FieldDecl *field = cast<FieldDecl>(*FI); |
| |
| bool baseObjectIsPointer = baseObjectExpr->getType()->isPointerType(); |
| |
| // Make a nameInfo that properly uses the anonymous name. |
| DeclarationNameInfo memberNameInfo(field->getDeclName(), loc); |
| |
| // Build the first member access in the chain with full information. |
| result = |
| BuildFieldReferenceExpr(result, baseObjectIsPointer, SourceLocation(), |
| SS, field, foundDecl, memberNameInfo) |
| .get(); |
| if (!result) |
| return ExprError(); |
| } |
| |
| // In all cases, we should now skip the first declaration in the chain. |
| ++FI; |
| |
| while (FI != FEnd) { |
| FieldDecl *field = cast<FieldDecl>(*FI++); |
| |
| // FIXME: these are somewhat meaningless |
| DeclarationNameInfo memberNameInfo(field->getDeclName(), loc); |
| DeclAccessPair fakeFoundDecl = |
| DeclAccessPair::make(field, field->getAccess()); |
| |
| result = |
| BuildFieldReferenceExpr(result, /*isarrow*/ false, SourceLocation(), |
| (FI == FEnd ? SS : EmptySS), field, |
| fakeFoundDecl, memberNameInfo) |
| .get(); |
| } |
| |
| return result; |
| } |
| |
| static ExprResult |
| BuildMSPropertyRefExpr(Sema &S, Expr *BaseExpr, bool IsArrow, |
| const CXXScopeSpec &SS, |
| MSPropertyDecl *PD, |
| const DeclarationNameInfo &NameInfo) { |
| // Property names are always simple identifiers and therefore never |
| // require any interesting additional storage. |
| return new (S.Context) MSPropertyRefExpr(BaseExpr, PD, IsArrow, |
| S.Context.PseudoObjectTy, VK_LValue, |
| SS.getWithLocInContext(S.Context), |
| NameInfo.getLoc()); |
| } |
| |
| MemberExpr *Sema::BuildMemberExpr( |
| Expr *Base, bool IsArrow, SourceLocation OpLoc, const CXXScopeSpec *SS, |
| SourceLocation TemplateKWLoc, ValueDecl *Member, DeclAccessPair FoundDecl, |
| bool HadMultipleCandidates, const DeclarationNameInfo &MemberNameInfo, |
| QualType Ty, ExprValueKind VK, ExprObjectKind OK, |
| const TemplateArgumentListInfo *TemplateArgs) { |
| NestedNameSpecifierLoc NNS = |
| SS ? SS->getWithLocInContext(Context) : NestedNameSpecifierLoc(); |
| return BuildMemberExpr(Base, IsArrow, OpLoc, NNS, TemplateKWLoc, Member, |
| FoundDecl, HadMultipleCandidates, MemberNameInfo, Ty, |
| VK, OK, TemplateArgs); |
| } |
| |
| MemberExpr *Sema::BuildMemberExpr( |
| Expr *Base, bool IsArrow, SourceLocation OpLoc, NestedNameSpecifierLoc NNS, |
| SourceLocation TemplateKWLoc, ValueDecl *Member, DeclAccessPair FoundDecl, |
| bool HadMultipleCandidates, const DeclarationNameInfo &MemberNameInfo, |
| QualType Ty, ExprValueKind VK, ExprObjectKind OK, |
| const TemplateArgumentListInfo *TemplateArgs) { |
| assert((!IsArrow || Base->isPRValue()) && |
| "-> base must be a pointer prvalue"); |
| MemberExpr *E = |
| MemberExpr::Create(Context, Base, IsArrow, OpLoc, NNS, TemplateKWLoc, |
| Member, FoundDecl, MemberNameInfo, TemplateArgs, Ty, |
| VK, OK, getNonOdrUseReasonInCurrentContext(Member)); |
| E->setHadMultipleCandidates(HadMultipleCandidates); |
| MarkMemberReferenced(E); |
| |
| // C++ [except.spec]p17: |
| // An exception-specification is considered to be needed when: |
| // - in an expression the function is the unique lookup result or the |
| // selected member of a set of overloaded functions |
| if (auto *FPT = Ty->getAs<FunctionProtoType>()) { |
| if (isUnresolvedExceptionSpec(FPT->getExceptionSpecType())) { |
| if (auto *NewFPT = ResolveExceptionSpec(MemberNameInfo.getLoc(), FPT)) |
| E->setType(Context.getQualifiedType(NewFPT, Ty.getQualifiers())); |
| } |
| } |
| |
| return E; |
| } |
| |
| /// Determine if the given scope is within a function-try-block handler. |
| static bool IsInFnTryBlockHandler(const Scope *S) { |
| // Walk the scope stack until finding a FnTryCatchScope, or leave the |
| // function scope. If a FnTryCatchScope is found, check whether the TryScope |
| // flag is set. If it is not, it's a function-try-block handler. |
| for (; S != S->getFnParent(); S = S->getParent()) { |
| if (S->getFlags() & Scope::FnTryCatchScope) |
| return (S->getFlags() & Scope::TryScope) != Scope::TryScope; |
| } |
| return false; |
| } |
| |
| ExprResult |
| Sema::BuildMemberReferenceExpr(Expr *BaseExpr, QualType BaseExprType, |
| SourceLocation OpLoc, bool IsArrow, |
| const CXXScopeSpec &SS, |
| SourceLocation TemplateKWLoc, |
| NamedDecl *FirstQualifierInScope, |
| LookupResult &R, |
| const TemplateArgumentListInfo *TemplateArgs, |
| const Scope *S, |
| bool SuppressQualifierCheck, |
| ActOnMemberAccessExtraArgs *ExtraArgs) { |
| QualType BaseType = BaseExprType; |
| if (IsArrow) { |
| assert(BaseType->isPointerType()); |
| BaseType = BaseType->castAs<PointerType>()->getPointeeType(); |
| } |
| R.setBaseObjectType(BaseType); |
| |
| // C++1z [expr.ref]p2: |
| // For the first option (dot) the first expression shall be a glvalue [...] |
| if (!IsArrow && BaseExpr && BaseExpr->isPRValue()) { |
| ExprResult Converted = TemporaryMaterializationConversion(BaseExpr); |
| if (Converted.isInvalid()) |
| return ExprError(); |
| BaseExpr = Converted.get(); |
| } |
| |
| const DeclarationNameInfo &MemberNameInfo = R.getLookupNameInfo(); |
| DeclarationName MemberName = MemberNameInfo.getName(); |
| SourceLocation MemberLoc = MemberNameInfo.getLoc(); |
| |
| if (R.isAmbiguous()) |
| return ExprError(); |
| |
| // [except.handle]p10: Referring to any non-static member or base class of an |
| // object in the handler for a function-try-block of a constructor or |
| // destructor for that object results in undefined behavior. |
| const auto *FD = getCurFunctionDecl(); |
| if (S && BaseExpr && FD && |
| (isa<CXXDestructorDecl>(FD) || isa<CXXConstructorDecl>(FD)) && |
| isa<CXXThisExpr>(BaseExpr->IgnoreImpCasts()) && |
| IsInFnTryBlockHandler(S)) |
| Diag(MemberLoc, diag::warn_cdtor_function_try_handler_mem_expr) |
| << isa<CXXDestructorDecl>(FD); |
| |
| if (R.empty()) { |
| // Rederive where we looked up. |
| DeclContext *DC = (SS.isSet() |
| ? computeDeclContext(SS, false) |
| : BaseType->castAs<RecordType>()->getDecl()); |
| |
| if (ExtraArgs) { |
| ExprResult RetryExpr; |
| if (!IsArrow && BaseExpr) { |
| SFINAETrap Trap(*this, true); |
| ParsedType ObjectType; |
| bool MayBePseudoDestructor = false; |
| RetryExpr = ActOnStartCXXMemberReference(getCurScope(), BaseExpr, |
| OpLoc, tok::arrow, ObjectType, |
| MayBePseudoDestructor); |
| if (RetryExpr.isUsable() && !Trap.hasErrorOccurred()) { |
| CXXScopeSpec TempSS(SS); |
| RetryExpr = ActOnMemberAccessExpr( |
| ExtraArgs->S, RetryExpr.get(), OpLoc, tok::arrow, TempSS, |
| TemplateKWLoc, ExtraArgs->Id, ExtraArgs->ObjCImpDecl); |
| } |
| if (Trap.hasErrorOccurred()) |
| RetryExpr = ExprError(); |
| } |
| if (RetryExpr.isUsable()) { |
| Diag(OpLoc, diag::err_no_member_overloaded_arrow) |
| << MemberName << DC << FixItHint::CreateReplacement(OpLoc, "->"); |
| return RetryExpr; |
| } |
| } |
| |
| Diag(R.getNameLoc(), diag::err_no_member) |
| << MemberName << DC |
| << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); |
| return ExprError(); |
| } |
| |
| // Diagnose lookups that find only declarations from a non-base |
| // type. This is possible for either qualified lookups (which may |
| // have been qualified with an unrelated type) or implicit member |
| // expressions (which were found with unqualified lookup and thus |
| // may have come from an enclosing scope). Note that it's okay for |
| // lookup to find declarations from a non-base type as long as those |
| // aren't the ones picked by overload resolution. |
| if ((SS.isSet() || !BaseExpr || |
| (isa<CXXThisExpr>(BaseExpr) && |
| cast<CXXThisExpr>(BaseExpr)->isImplicit())) && |
| !SuppressQualifierCheck && |
| CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) |
| return ExprError(); |
| |
| // Construct an unresolved result if we in fact got an unresolved |
| // result. |
| if (R.isOverloadedResult() || R.isUnresolvableResult()) { |
| // Suppress any lookup-related diagnostics; we'll do these when we |
| // pick a member. |
| R.suppressDiagnostics(); |
| |
| UnresolvedMemberExpr *MemExpr |
| = UnresolvedMemberExpr::Create(Context, R.isUnresolvableResult(), |
| BaseExpr, BaseExprType, |
| IsArrow, OpLoc, |
| SS.getWithLocInContext(Context), |
| TemplateKWLoc, MemberNameInfo, |
| TemplateArgs, R.begin(), R.end()); |
| |
| return MemExpr; |
| } |
| |
| assert(R.isSingleResult()); |
| DeclAccessPair FoundDecl = R.begin().getPair(); |
| NamedDecl *MemberDecl = R.getFoundDecl(); |
| |
| // FIXME: diagnose the presence of template arguments now. |
| |
| // If the decl being referenced had an error, return an error for this |
| // sub-expr without emitting another error, in order to avoid cascading |
| // error cases. |
| if (MemberDecl->isInvalidDecl()) |
| return ExprError(); |
| |
| // Handle the implicit-member-access case. |
| if (!BaseExpr) { |
| // If this is not an instance member, convert to a non-member access. |
| if (!MemberDecl->isCXXInstanceMember()) { |
| // We might have a variable template specialization (or maybe one day a |
| // member concept-id). |
| if (TemplateArgs || TemplateKWLoc.isValid()) |
| return BuildTemplateIdExpr(SS, TemplateKWLoc, R, /*ADL*/false, TemplateArgs); |
| |
| return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), MemberDecl, |
| FoundDecl, TemplateArgs); |
| } |
| SourceLocation Loc = R.getNameLoc(); |
| if (SS.getRange().isValid()) |
| Loc = SS.getRange().getBegin(); |
| BaseExpr = BuildCXXThisExpr(Loc, BaseExprType, /*IsImplicit=*/true); |
| } |
| |
| // Check the use of this member. |
| if (DiagnoseUseOfDecl(MemberDecl, MemberLoc)) |
| return ExprError(); |
| |
| if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) |
| return BuildFieldReferenceExpr(BaseExpr, IsArrow, OpLoc, SS, FD, FoundDecl, |
| MemberNameInfo); |
| |
| if (MSPropertyDecl *PD = dyn_cast<MSPropertyDecl>(MemberDecl)) |
| return BuildMSPropertyRefExpr(*this, BaseExpr, IsArrow, SS, PD, |
| MemberNameInfo); |
| |
| if (IndirectFieldDecl *FD = dyn_cast<IndirectFieldDecl>(MemberDecl)) |
| // We may have found a field within an anonymous union or struct |
| // (C++ [class.union]). |
| return BuildAnonymousStructUnionMemberReference(SS, MemberLoc, FD, |
| FoundDecl, BaseExpr, |
| OpLoc); |
| |
| if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { |
| return BuildMemberExpr(BaseExpr, IsArrow, OpLoc, &SS, TemplateKWLoc, Var, |
| FoundDecl, /*HadMultipleCandidates=*/false, |
| MemberNameInfo, Var->getType().getNonReferenceType(), |
| VK_LValue, OK_Ordinary); |
| } |
| |
| if (CXXMethodDecl *MemberFn = dyn_cast<CXXMethodDecl>(MemberDecl)) { |
| ExprValueKind valueKind; |
| QualType type; |
| if (MemberFn->isInstance()) { |
| valueKind = VK_PRValue; |
| type = Context.BoundMemberTy; |
| } else { |
| valueKind = VK_LValue; |
| type = MemberFn->getType(); |
| } |
| |
| return BuildMemberExpr(BaseExpr, IsArrow, OpLoc, &SS, TemplateKWLoc, |
| MemberFn, FoundDecl, /*HadMultipleCandidates=*/false, |
| MemberNameInfo, type, valueKind, OK_Ordinary); |
| } |
| assert(!isa<FunctionDecl>(MemberDecl) && "member function not C++ method?"); |
| |
| if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { |
| return BuildMemberExpr(BaseExpr, IsArrow, OpLoc, &SS, TemplateKWLoc, Enum, |
| FoundDecl, /*HadMultipleCandidates=*/false, |
| MemberNameInfo, Enum->getType(), VK_PRValue, |
| OK_Ordinary); |
| } |
| |
| if (VarTemplateDecl *VarTempl = dyn_cast<VarTemplateDecl>(MemberDecl)) { |
| if (!TemplateArgs) { |
| diagnoseMissingTemplateArguments(TemplateName(VarTempl), MemberLoc); |
| return ExprError(); |
| } |
| |
| DeclResult VDecl = CheckVarTemplateId(VarTempl, TemplateKWLoc, |
| MemberNameInfo.getLoc(), *TemplateArgs); |
| if (VDecl.isInvalid()) |
| return ExprError(); |
| |
| // Non-dependent member, but dependent template arguments. |
| if (!VDecl.get()) |
| return ActOnDependentMemberExpr( |
| BaseExpr, BaseExpr->getType(), IsArrow, OpLoc, SS, TemplateKWLoc, |
| FirstQualifierInScope, MemberNameInfo, TemplateArgs); |
| |
| VarDecl *Var = cast<VarDecl>(VDecl.get()); |
| if (!Var->getTemplateSpecializationKind()) |
| Var->setTemplateSpecializationKind(TSK_ImplicitInstantiation, MemberLoc); |
| |
| return BuildMemberExpr( |
| BaseExpr, IsArrow, OpLoc, &SS, TemplateKWLoc, Var, FoundDecl, |
| /*HadMultipleCandidates=*/false, MemberNameInfo, |
| Var->getType().getNonReferenceType(), VK_LValue, OK_Ordinary); |
| } |
| |
| // We found something that we didn't expect. Complain. |
| if (isa<TypeDecl>(MemberDecl)) |
| Diag(MemberLoc, diag::err_typecheck_member_reference_type) |
| << MemberName << BaseType << int(IsArrow); |
| else |
| Diag(MemberLoc, diag::err_typecheck_member_reference_unknown) |
| << MemberName << BaseType << int(IsArrow); |
| |
| Diag(MemberDecl->getLocation(), diag::note_member_declared_here) |
| << MemberName; |
| R.suppressDiagnostics(); |
| return ExprError(); |
| } |
| |
| /// Given that normal member access failed on the given expression, |
| /// and given that the expression's type involves builtin-id or |
| /// builtin-Class, decide whether substituting in the redefinition |
| /// types would be profitable. The redefinition type is whatever |
| /// this translation unit tried to typedef to id/Class; we store |
| /// it to the side and then re-use it in places like this. |
| static bool ShouldTryAgainWithRedefinitionType(Sema &S, ExprResult &base) { |
| const ObjCObjectPointerType *opty |
| = base.get()->getType()->getAs<ObjCObjectPointerType>(); |
| if (!opty) return false; |
| |
| const ObjCObjectType *ty = opty->getObjectType(); |
| |
| QualType redef; |
| if (ty->isObjCId()) { |
| redef = S.Context.getObjCIdRedefinitionType(); |
| } else if (ty->isObjCClass()) { |
| redef = S.Context.getObjCClassRedefinitionType(); |
| } else { |
| return false; |
| } |
| |
| // Do the substitution as long as the redefinition type isn't just a |
| // possibly-qualified pointer to builtin-id or builtin-Class again. |
| opty = redef->getAs<ObjCObjectPointerType>(); |
| if (opty && !opty->getObjectType()->getInterface()) |
| return false; |
| |
| base = S.ImpCastExprToType(base.get(), redef, CK_BitCast); |
| return true; |
| } |
| |
| static bool isRecordType(QualType T) { |
| return T->isRecordType(); |
| } |
| static bool isPointerToRecordType(QualType T) { |
| if (const PointerType *PT = T->getAs<PointerType>()) |
| return PT->getPointeeType()->isRecordType(); |
| return false; |
| } |
| |
| /// Perform conversions on the LHS of a member access expression. |
| ExprResult |
| Sema::PerformMemberExprBaseConversion(Expr *Base, bool IsArrow) { |
| if (IsArrow && !Base->getType()->isFunctionType()) |
| return DefaultFunctionArrayLvalueConversion(Base); |
| |
| return CheckPlaceholderExpr(Base); |
| } |
| |
| /// Look up the given member of the given non-type-dependent |
| /// expression. This can return in one of two ways: |
| /// * If it returns a sentinel null-but-valid result, the caller will |
| /// assume that lookup was performed and the results written into |
| /// the provided structure. It will take over from there. |
| /// * Otherwise, the returned expression will be produced in place of |
| /// an ordinary member expression. |
| /// |
| /// The ObjCImpDecl bit is a gross hack that will need to be properly |
| /// fixed for ObjC++. |
| static ExprResult LookupMemberExpr(Sema &S, LookupResult &R, |
| ExprResult &BaseExpr, bool &IsArrow, |
| SourceLocation OpLoc, CXXScopeSpec &SS, |
| Decl *ObjCImpDecl, bool HasTemplateArgs, |
| SourceLocation TemplateKWLoc) { |
| assert(BaseExpr.get() && "no base expression"); |
| |
| // Perform default conversions. |
| BaseExpr = S.PerformMemberExprBaseConversion(BaseExpr.get(), IsArrow); |
| if (BaseExpr.isInvalid()) |
| return ExprError(); |
| |
| QualType BaseType = BaseExpr.get()->getType(); |
| assert(!BaseType->isDependentType()); |
| |
| DeclarationName MemberName = R.getLookupName(); |
| SourceLocation MemberLoc = R.getNameLoc(); |
| |
| // For later type-checking purposes, turn arrow accesses into dot |
| // accesses. The only access type we support that doesn't follow |
| // the C equivalence "a->b === (*a).b" is ObjC property accesses, |
| // and those never use arrows, so this is unaffected. |
| if (IsArrow) { |
| if (const PointerType *Ptr = BaseType->getAs<PointerType>()) |
| BaseType = Ptr->getPointeeType(); |
| else if (const ObjCObjectPointerType *Ptr |
| = BaseType->getAs<ObjCObjectPointerType>()) |
| BaseType = Ptr->getPointeeType(); |
| else if (BaseType->isRecordType()) { |
| // Recover from arrow accesses to records, e.g.: |
| // struct MyRecord foo; |
| // foo->bar |
| // This is actually well-formed in C++ if MyRecord has an |
| // overloaded operator->, but that should have been dealt with |
| // by now--or a diagnostic message already issued if a problem |
| // was encountered while looking for the overloaded operator->. |
| if (!S.getLangOpts().CPlusPlus) { |
| S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) |
| << BaseType << int(IsArrow) << BaseExpr.get()->getSourceRange() |
| << FixItHint::CreateReplacement(OpLoc, "."); |
| } |
| IsArrow = false; |
| } else if (BaseType->isFunctionType()) { |
| goto fail; |
| } else { |
| S.Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) |
| << BaseType << BaseExpr.get()->getSourceRange(); |
| return ExprError(); |
| } |
| } |
| |
| // Handle field access to simple records. |
| if (const RecordType *RTy = BaseType->getAs<RecordType>()) { |
| TypoExpr *TE = nullptr; |
| if (LookupMemberExprInRecord(S, R, BaseExpr.get(), RTy, OpLoc, IsArrow, SS, |
| HasTemplateArgs, TemplateKWLoc, TE)) |
| return ExprError(); |
| |
| // Returning valid-but-null is how we indicate to the caller that |
| // the lookup result was filled in. If typo correction was attempted and |
| // failed, the lookup result will have been cleared--that combined with the |
| // valid-but-null ExprResult will trigger the appropriate diagnostics. |
| return ExprResult(TE); |
| } |
| |
| // Handle ivar access to Objective-C objects. |
| if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>()) { |
| if (!SS.isEmpty() && !SS.isInvalid()) { |
| S.Diag(SS.getRange().getBegin(), diag::err_qualified_objc_access) |
| << 1 << SS.getScopeRep() |
| << FixItHint::CreateRemoval(SS.getRange()); |
| SS.clear(); |
| } |
| |
| IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); |
| |
| // There are three cases for the base type: |
| // - builtin id (qualified or unqualified) |
| // - builtin Class (qualified or unqualified) |
| // - an interface |
| ObjCInterfaceDecl *IDecl = OTy->getInterface(); |
| if (!IDecl) { |
| if (S.getLangOpts().ObjCAutoRefCount && |
| (OTy->isObjCId() || OTy->isObjCClass())) |
| goto fail; |
| // There's an implicit 'isa' ivar on all objects. |
| // But we only actually find it this way on objects of type 'id', |
| // apparently. |
| if (OTy->isObjCId() && Member->isStr("isa")) |
| return new (S.Context) ObjCIsaExpr(BaseExpr.get(), IsArrow, MemberLoc, |
| OpLoc, S.Context.getObjCClassType()); |
| if (ShouldTryAgainWithRedefinitionType(S, BaseExpr)) |
| return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS, |
| ObjCImpDecl, HasTemplateArgs, TemplateKWLoc); |
| goto fail; |
| } |
| |
| if (S.RequireCompleteType(OpLoc, BaseType, |
| diag::err_typecheck_incomplete_tag, |
| BaseExpr.get())) |
| return ExprError(); |
| |
| ObjCInterfaceDecl *ClassDeclared = nullptr; |
| ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); |
| |
| if (!IV) { |
| // Attempt to correct for typos in ivar names. |
| DeclFilterCCC<ObjCIvarDecl> Validator{}; |
| Validator.IsObjCIvarLookup = IsArrow; |
| if (TypoCorrection Corrected = S.CorrectTypo( |
| R.getLookupNameInfo(), Sema::LookupMemberName, nullptr, nullptr, |
| Validator, Sema::CTK_ErrorRecovery, IDecl)) { |
| IV = Corrected.getCorrectionDeclAs<ObjCIvarDecl>(); |
| S.diagnoseTypo( |
| Corrected, |
| S.PDiag(diag::err_typecheck_member_reference_ivar_suggest) |
| << IDecl->getDeclName() << MemberName); |
| |
| // Figure out the class that declares the ivar. |
| assert(!ClassDeclared); |
| |
| Decl *D = cast<Decl>(IV->getDeclContext()); |
| if (auto *Category = dyn_cast<ObjCCategoryDecl>(D)) |
| D = Category->getClassInterface(); |
| |
| if (auto *Implementation = dyn_cast<ObjCImplementationDecl>(D)) |
| ClassDeclared = Implementation->getClassInterface(); |
| else if (auto *Interface = dyn_cast<ObjCInterfaceDecl>(D)) |
| ClassDeclared = Interface; |
| |
| assert(ClassDeclared && "cannot query interface"); |
| } else { |
| if (IsArrow && |
| IDecl->FindPropertyDeclaration( |
| Member, ObjCPropertyQueryKind::OBJC_PR_query_instance)) { |
| S.Diag(MemberLoc, diag::err_property_found_suggest) |
| << Member << BaseExpr.get()->getType() |
| << FixItHint::CreateReplacement(OpLoc, "."); |
| return ExprError(); |
| } |
| |
| S.Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) |
| << IDecl->getDeclName() << MemberName |
| << BaseExpr.get()->getSourceRange(); |
| return ExprError(); |
| } |
| } |
| |
| assert(ClassDeclared); |
| |
| // If the decl being referenced had an error, return an error for this |
| // sub-expr without emitting another error, in order to avoid cascading |
| // error cases. |
| if (IV->isInvalidDecl()) |
| return ExprError(); |
| |
| // Check whether we can reference this field. |
| if (S.DiagnoseUseOfDecl(IV, MemberLoc)) |
| return ExprError(); |
| if (IV->getAccessControl() != ObjCIvarDecl::Public && |
| IV->getAccessControl() != ObjCIvarDecl::Package) { |
| ObjCInterfaceDecl *ClassOfMethodDecl = nullptr; |
| if (ObjCMethodDecl *MD = S.getCurMethodDecl()) |
| ClassOfMethodDecl = MD->getClassInterface(); |
| else if (ObjCImpDecl && S.getCurFunctionDecl()) { |
| // Case of a c-function declared inside an objc implementation. |
| // FIXME: For a c-style function nested inside an objc implementation |
| // class, there is no implementation context available, so we pass |
| // down the context as argument to this routine. Ideally, this context |
| // need be passed down in the AST node and somehow calculated from the |
| // AST for a function decl. |
| if (ObjCImplementationDecl *IMPD = |
| dyn_cast<ObjCImplementationDecl>(ObjCImpDecl)) |
| ClassOfMethodDecl = IMPD->getClassInterface(); |
| else if (ObjCCategoryImplDecl* CatImplClass = |
| dyn_cast<ObjCCategoryImplDecl>(ObjCImpDecl)) |
| ClassOfMethodDecl = CatImplClass->getClassInterface(); |
| } |
| if (!S.getLangOpts().DebuggerSupport) { |
| if (IV->getAccessControl() == ObjCIvarDecl::Private) { |
| if (!declaresSameEntity(ClassDeclared, IDecl) || |
| !declaresSameEntity(ClassOfMethodDecl, ClassDeclared)) |
| S.Diag(MemberLoc, diag::err_private_ivar_access) |
| << IV->getDeclName(); |
| } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) |
| // @protected |
| S.Diag(MemberLoc, diag::err_protected_ivar_access) |
| << IV->getDeclName(); |
| } |
| } |
| bool warn = true; |
| if (S.getLangOpts().ObjCWeak) { |
| Expr *BaseExp = BaseExpr.get()->IgnoreParenImpCasts(); |
| if (UnaryOperator *UO = dyn_cast<UnaryOperator>(BaseExp)) |
| if (UO->getOpcode() == UO_Deref) |
| BaseExp = UO->getSubExpr()->IgnoreParenCasts(); |
| |
| if (DeclRefExpr *DE = dyn_cast<DeclRefExpr>(BaseExp)) |
| if (DE->getType().getObjCLifetime() == Qualifiers::OCL_Weak) { |
| S.Diag(DE->getLocation(), diag::err_arc_weak_ivar_access); |
| warn = false; |
| } |
| } |
| if (warn) { |
| if (ObjCMethodDecl *MD = S.getCurMethodDecl()) { |
| ObjCMethodFamily MF = MD->getMethodFamily(); |
| warn = (MF != OMF_init && MF != OMF_dealloc && |
| MF != OMF_finalize && |
| !S.IvarBacksCurrentMethodAccessor(IDecl, MD, IV)); |
| } |
| if (warn) |
| S.Diag(MemberLoc, diag::warn_direct_ivar_access) << IV->getDeclName(); |
| } |
| |
| ObjCIvarRefExpr *Result = new (S.Context) ObjCIvarRefExpr( |
| IV, IV->getUsageType(BaseType), MemberLoc, OpLoc, BaseExpr.get(), |
| IsArrow); |
| |
| if (IV->getType().getObjCLifetime() == Qualifiers::OCL_Weak) { |
| if (!S.isUnevaluatedContext() && |
| !S.Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, MemberLoc)) |
| S.getCurFunction()->recordUseOfWeak(Result); |
| } |
| |
| return Result; |
| } |
| |
| // Objective-C property access. |
| const ObjCObjectPointerType *OPT; |
| if (!IsArrow && (OPT = BaseType->getAs<ObjCObjectPointerType>())) { |
| if (!SS.isEmpty() && !SS.isInvalid()) { |
| S.Diag(SS.getRange().getBegin(), diag::err_qualified_objc_access) |
| << 0 << SS.getScopeRep() << FixItHint::CreateRemoval(SS.getRange()); |
| SS.clear(); |
| } |
| |
| // This actually uses the base as an r-value. |
| BaseExpr = S.DefaultLvalueConversion(BaseExpr.get()); |
| if (BaseExpr.isInvalid()) |
| return ExprError(); |
| |
| assert(S.Context.hasSameUnqualifiedType(BaseType, |
| BaseExpr.get()->getType())); |
| |
| IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); |
| |
| const ObjCObjectType *OT = OPT->getObjectType(); |
| |
| // id, with and without qualifiers. |
| if (OT->isObjCId()) { |
| // Check protocols on qualified interfaces. |
| Selector Sel = S.PP.getSelectorTable().getNullarySelector(Member); |
| if (Decl *PMDecl = |
| FindGetterSetterNameDecl(OPT, Member, Sel, S.Context)) { |
| if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { |
| // Check the use of this declaration |
| if (S.DiagnoseUseOfDecl(PD, MemberLoc)) |
| return ExprError(); |
| |
| return new (S.Context) |
| ObjCPropertyRefExpr(PD, S.Context.PseudoObjectTy, VK_LValue, |
| OK_ObjCProperty, MemberLoc, BaseExpr.get()); |
| } |
| |
| if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { |
| Selector SetterSel = |
| SelectorTable::constructSetterSelector(S.PP.getIdentifierTable(), |
| S.PP.getSelectorTable(), |
| Member); |
| ObjCMethodDecl *SMD = nullptr; |
| if (Decl *SDecl = FindGetterSetterNameDecl(OPT, |
| /*Property id*/ nullptr, |
| SetterSel, S.Context)) |
| SMD = dyn_cast<ObjCMethodDecl>(SDecl); |
| |
| return new (S.Context) |
| ObjCPropertyRefExpr(OMD, SMD, S.Context.PseudoObjectTy, VK_LValue, |
| OK_ObjCProperty, MemberLoc, BaseExpr.get()); |
| } |
| } |
| // Use of id.member can only be for a property reference. Do not |
| // use the 'id' redefinition in this case. |
| if (IsArrow && ShouldTryAgainWithRedefinitionType(S, BaseExpr)) |
| return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS, |
| ObjCImpDecl, HasTemplateArgs, TemplateKWLoc); |
| |
| return ExprError(S.Diag(MemberLoc, diag::err_property_not_found) |
| << MemberName << BaseType); |
| } |
| |
| // 'Class', unqualified only. |
| if (OT->isObjCClass()) { |
| // Only works in a method declaration (??!). |
| ObjCMethodDecl *MD = S.getCurMethodDecl(); |
| if (!MD) { |
| if (ShouldTryAgainWithRedefinitionType(S, BaseExpr)) |
| return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS, |
| ObjCImpDecl, HasTemplateArgs, TemplateKWLoc); |
| |
| goto fail; |
| } |
| |
| // Also must look for a getter name which uses property syntax. |
| Selector Sel = S.PP.getSelectorTable().getNullarySelector(Member); |
| ObjCInterfaceDecl *IFace = MD->getClassInterface(); |
| if (!IFace) |
| goto fail; |
| |
| ObjCMethodDecl *Getter; |
| if ((Getter = IFace->lookupClassMethod(Sel))) { |
| // Check the use of this method. |
| if (S.DiagnoseUseOfDecl(Getter, MemberLoc)) |
| return ExprError(); |
| } else |
| Getter = IFace->lookupPrivateMethod(Sel, false); |
| // If we found a getter then this may be a valid dot-reference, we |
| // will look for the matching setter, in case it is needed. |
| Selector SetterSel = |
| SelectorTable::constructSetterSelector(S.PP.getIdentifierTable(), |
| S.PP.getSelectorTable(), |
| Member); |
| ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); |
| if (!Setter) { |
| // If this reference is in an @implementation, also check for 'private' |
| // methods. |
| Setter = IFace->lookupPrivateMethod(SetterSel, false); |
| } |
| |
| if (Setter && S.DiagnoseUseOfDecl(Setter, MemberLoc)) |
| return ExprError(); |
| |
| if (Getter || Setter) { |
| return new (S.Context) ObjCPropertyRefExpr( |
| Getter, Setter, S.Context.PseudoObjectTy, VK_LValue, |
| OK_ObjCProperty, MemberLoc, BaseExpr.get()); |
| } |
| |
| if (ShouldTryAgainWithRedefinitionType(S, BaseExpr)) |
| return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS, |
| ObjCImpDecl, HasTemplateArgs, TemplateKWLoc); |
| |
| return ExprError(S.Diag(MemberLoc, diag::err_property_not_found) |
| << MemberName << BaseType); |
| } |
| |
| // Normal property access. |
| return S.HandleExprPropertyRefExpr(OPT, BaseExpr.get(), OpLoc, MemberName, |
| MemberLoc, SourceLocation(), QualType(), |
| false); |
| } |
| |
| // Handle 'field access' to vectors, such as 'V.xx'. |
| if (BaseType->isExtVectorType()) { |
| // FIXME: this expr should store IsArrow. |
| IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); |
| ExprValueKind VK; |
| if (IsArrow) |
| VK = VK_LValue; |
| else { |
| if (PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(BaseExpr.get())) |
| VK = POE->getSyntacticForm()->getValueKind(); |
| else |
| VK = BaseExpr.get()->getValueKind(); |
| } |
| |
| QualType ret = CheckExtVectorComponent(S, BaseType, VK, OpLoc, |
| Member, MemberLoc); |
| if (ret.isNull()) |
| return ExprError(); |
| Qualifiers BaseQ = |
| S.Context.getCanonicalType(BaseExpr.get()->getType()).getQualifiers(); |
| ret = S.Context.getQualifiedType(ret, BaseQ); |
| |
| return new (S.Context) |
| ExtVectorElementExpr(ret, VK, BaseExpr.get(), *Member, MemberLoc); |
| } |
| |
| // Adjust builtin-sel to the appropriate redefinition type if that's |
| // not just a pointer to builtin-sel again. |
| if (IsArrow && BaseType->isSpecificBuiltinType(BuiltinType::ObjCSel) && |
| !S.Context.getObjCSelRedefinitionType()->isObjCSelType()) { |
| BaseExpr = S.ImpCastExprToType( |
| BaseExpr.get(), S.Context.getObjCSelRedefinitionType(), CK_BitCast); |
| return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS, |
| ObjCImpDecl, HasTemplateArgs, TemplateKWLoc); |
| } |
| |
| // Failure cases. |
| fail: |
| |
| // Recover from dot accesses to pointers, e.g.: |
| // type *foo; |
| // foo.bar |
| // This is actually well-formed in two cases: |
| // - 'type' is an Objective C type |
| // - 'bar' is a pseudo-destructor name which happens to refer to |
| // the appropriate pointer type |
| if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { |
| if (!IsArrow && Ptr->getPointeeType()->isRecordType() && |
| MemberName.getNameKind() != DeclarationName::CXXDestructorName) { |
| S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) |
| << BaseType << int(IsArrow) << BaseExpr.get()->getSourceRange() |
| << FixItHint::CreateReplacement(OpLoc, "->"); |
| |
| // Recurse as an -> access. |
| IsArrow = true; |
| return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS, |
| ObjCImpDecl, HasTemplateArgs, TemplateKWLoc); |
| } |
| } |
| |
| // If the user is trying to apply -> or . to a function name, it's probably |
| // because they forgot parentheses to call that function. |
| if (S.tryToRecoverWithCall( |
| BaseExpr, S.PDiag(diag::err_member_reference_needs_call), |
| /*complain*/ false, |
| IsArrow ? &isPointerToRecordType : &isRecordType)) { |
| if (BaseExpr.isInvalid()) |
| return ExprError(); |
| BaseExpr = S.DefaultFunctionArrayConversion(BaseExpr.get()); |
| return LookupMemberExpr(S, R, BaseExpr, IsArrow, OpLoc, SS, |
| ObjCImpDecl, HasTemplateArgs, TemplateKWLoc); |
| } |
| |
| S.Diag(OpLoc, diag::err_typecheck_member_reference_struct_union) |
| << BaseType << BaseExpr.get()->getSourceRange() << MemberLoc; |
| |
| return ExprError(); |
| } |
| |
| /// The main callback when the parser finds something like |
| /// expression . [nested-name-specifier] identifier |
| /// expression -> [nested-name-specifier] identifier |
| /// where 'identifier' encompasses a fairly broad spectrum of |
| /// possibilities, including destructor and operator references. |
| /// |
| /// \param OpKind either tok::arrow or tok::period |
| /// \param ObjCImpDecl the current Objective-C \@implementation |
| /// decl; this is an ugly hack around the fact that Objective-C |
| /// \@implementations aren't properly put in the context chain |
| ExprResult Sema::ActOnMemberAccessExpr(Scope *S, Expr *Base, |
| SourceLocation OpLoc, |
| tok::TokenKind OpKind, |
| CXXScopeSpec &SS, |
| SourceLocation TemplateKWLoc, |
| UnqualifiedId &Id, |
| Decl *ObjCImpDecl) { |
| if (SS.isSet() && SS.isInvalid()) |
| return ExprError(); |
| |
| // Warn about the explicit constructor calls Microsoft extension. |
| if (getLangOpts().MicrosoftExt && |
| Id.getKind() == UnqualifiedIdKind::IK_ConstructorName) |
| Diag(Id.getSourceRange().getBegin(), |
| diag::ext_ms_explicit_constructor_call); |
| |
| TemplateArgumentListInfo TemplateArgsBuffer; |
| |
| // Decompose the name into its component parts. |
| DeclarationNameInfo NameInfo; |
| const TemplateArgumentListInfo *TemplateArgs; |
| DecomposeUnqualifiedId(Id, TemplateArgsBuffer, |
| NameInfo, TemplateArgs); |
| |
| DeclarationName Name = NameInfo.getName(); |
| bool IsArrow = (OpKind == tok::arrow); |
| |
| NamedDecl *FirstQualifierInScope |
| = (!SS.isSet() ? nullptr : FindFirstQualifierInScope(S, SS.getScopeRep())); |
| |
| // This is a postfix expression, so get rid of ParenListExprs. |
| ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); |
| if (Result.isInvalid()) return ExprError(); |
| Base = Result.get(); |
| |
| if (Base->getType()->isDependentType() || Name.isDependentName() || |
| isDependentScopeSpecifier(SS)) { |
| return ActOnDependentMemberExpr(Base, Base->getType(), IsArrow, OpLoc, SS, |
| TemplateKWLoc, FirstQualifierInScope, |
| NameInfo, TemplateArgs); |
| } |
| |
| ActOnMemberAccessExtraArgs ExtraArgs = {S, Id, ObjCImpDecl}; |
| ExprResult Res = BuildMemberReferenceExpr( |
| Base, Base->getType(), OpLoc, IsArrow, SS, TemplateKWLoc, |
| FirstQualifierInScope, NameInfo, TemplateArgs, S, &ExtraArgs); |
| |
| if (!Res.isInvalid() && isa<MemberExpr>(Res.get())) |
| CheckMemberAccessOfNoDeref(cast<MemberExpr>(Res.get())); |
| |
| return Res; |
| } |
| |
| void Sema::CheckMemberAccessOfNoDeref(const MemberExpr *E) { |
| if (isUnevaluatedContext()) |
| return; |
| |
| QualType ResultTy = E->getType(); |
| |
| // Member accesses have four cases: |
| // 1: non-array member via "->": dereferences |
| // 2: non-array member via ".": nothing interesting happens |
| // 3: array member access via "->": nothing interesting happens |
| // (this returns an array lvalue and does not actually dereference memory) |
| // 4: array member access via ".": *adds* a layer of indirection |
| if (ResultTy->isArrayType()) { |
| if (!E->isArrow()) { |
| // This might be something like: |
| // (*structPtr).arrayMember |
| // which behaves roughly like: |
| // &(*structPtr).pointerMember |
| // in that the apparent dereference in the base expression does not |
| // actually happen. |
| CheckAddressOfNoDeref(E->getBase()); |
| } |
| } else if (E->isArrow()) { |
| if (const auto *Ptr = dyn_cast<PointerType>( |
| E->getBase()->getType().getDesugaredType(Context))) { |
| if (Ptr->getPointeeType()->hasAttr(attr::NoDeref)) |
| ExprEvalContexts.back().PossibleDerefs.insert(E); |
| } |
| } |
| } |
| |
| ExprResult |
| Sema::BuildFieldReferenceExpr(Expr *BaseExpr, bool IsArrow, |
| SourceLocation OpLoc, const CXXScopeSpec &SS, |
| FieldDecl *Field, DeclAccessPair FoundDecl, |
| const DeclarationNameInfo &MemberNameInfo) { |
| // x.a is an l-value if 'a' has a reference type. Otherwise: |
| // x.a is an l-value/x-value/pr-value if the base is (and note |
| // that *x is always an l-value), except that if the base isn't |
| // an ordinary object then we must have an rvalue. |
| ExprValueKind VK = VK_LValue; |
| ExprObjectKind OK = OK_Ordinary; |
| if (!IsArrow) { |
| if (BaseExpr->getObjectKind() == OK_Ordinary) |
| VK = BaseExpr->getValueKind(); |
| else |
| VK = VK_PRValue; |
| } |
| if (VK != VK_PRValue && Field->isBitField()) |
| OK = OK_BitField; |
| |
| // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] |
| QualType MemberType = Field->getType(); |
| if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) { |
| MemberType = Ref->getPointeeType(); |
| VK = VK_LValue; |
| } else { |
| QualType BaseType = BaseExpr->getType(); |
| if (IsArrow) BaseType = BaseType->castAs<PointerType>()->getPointeeType(); |
| |
| Qualifiers BaseQuals = BaseType.getQualifiers(); |
| |
| // GC attributes are never picked up by members. |
| BaseQuals.removeObjCGCAttr(); |
| |
| // CVR attributes from the base are picked up by members, |
| // except that 'mutable' members don't pick up 'const'. |
| if (Field->isMutable()) BaseQuals.removeConst(); |
| |
| Qualifiers MemberQuals = |
| Context.getCanonicalType(MemberType).getQualifiers(); |
| |
| assert(!MemberQuals.hasAddressSpace()); |
| |
| Qualifiers Combined = BaseQuals + MemberQuals; |
| if (Combined != MemberQuals) |
| MemberType = Context.getQualifiedType(MemberType, Combined); |
| |
| // Pick up NoDeref from the base in case we end up using AddrOf on the |
| // result. E.g. the expression |
| // &someNoDerefPtr->pointerMember |
| // should be a noderef pointer again. |
| if (BaseType->hasAttr(attr::NoDeref)) |
| MemberType = |
| Context.getAttributedType(attr::NoDeref, MemberType, MemberType); |
| } |
| |
| auto *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); |
| if (!(CurMethod && CurMethod->isDefaulted())) |
| UnusedPrivateFields.remove(Field); |
| |
| ExprResult Base = PerformObjectMemberConversion(BaseExpr, SS.getScopeRep(), |
| FoundDecl, Field); |
| if (Base.isInvalid()) |
| return ExprError(); |
| |
| // Build a reference to a private copy for non-static data members in |
| // non-static member functions, privatized by OpenMP constructs. |
| if (getLangOpts().OpenMP && IsArrow && |
| !CurContext->isDependentContext() && |
| isa<CXXThisExpr>(Base.get()->IgnoreParenImpCasts())) { |
| if (auto *PrivateCopy = isOpenMPCapturedDecl(Field)) { |
| return getOpenMPCapturedExpr(PrivateCopy, VK, OK, |
| MemberNameInfo.getLoc()); |
| } |
| } |
| |
| return BuildMemberExpr(Base.get(), IsArrow, OpLoc, &SS, |
| /*TemplateKWLoc=*/SourceLocation(), Field, FoundDecl, |
| /*HadMultipleCandidates=*/false, MemberNameInfo, |
| MemberType, VK, OK); |
| } |
| |
| /// Builds an implicit member access expression. The current context |
| /// is known to be an instance method, and the given unqualified lookup |
| /// set is known to contain only instance members, at least one of which |
| /// is from an appropriate type. |
| ExprResult |
| Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, |
| SourceLocation TemplateKWLoc, |
| LookupResult &R, |
| const TemplateArgumentListInfo *TemplateArgs, |
| bool IsKnownInstance, const Scope *S) { |
| assert(!R.empty() && !R.isAmbiguous()); |
| |
| SourceLocation loc = R.getNameLoc(); |
| |
| // If this is known to be an instance access, go ahead and build an |
| // implicit 'this' expression now. |
| QualType ThisTy = getCurrentThisType(); |
| assert(!ThisTy.isNull() && "didn't correctly pre-flight capture of 'this'"); |
| |
| Expr *baseExpr = nullptr; // null signifies implicit access |
| if (IsKnownInstance) { |
| SourceLocation Loc = R.getNameLoc(); |
| if (SS.getRange().isValid()) |
| Loc = SS.getRange().getBegin(); |
| baseExpr = BuildCXXThisExpr(loc, ThisTy, /*IsImplicit=*/true); |
| } |
| |
| return BuildMemberReferenceExpr(baseExpr, ThisTy, |
| /*OpLoc*/ SourceLocation(), |
| /*IsArrow*/ true, |
| SS, TemplateKWLoc, |
| /*FirstQualifierInScope*/ nullptr, |
| R, TemplateArgs, S); |
| } |