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diff --git a/clang/lib/Sema/SemaExprMember.cpp b/clang/lib/Sema/SemaExprMember.cpp
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+//===--- SemaExprMember.cpp - Semantic Analysis for Expressions -----------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements semantic analysis member access expressions.
+//
+//===----------------------------------------------------------------------===//
+#include "clang/Sema/SemaInternal.h"
+#include "clang/Sema/Lookup.h"
+#include "clang/Sema/Scope.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"
+
+using namespace clang;
+using namespace sema;
+
+/// Determines if the given class is provably not derived from all of
+/// the prospective base classes.
+static bool IsProvablyNotDerivedFrom(Sema &SemaRef,
+ CXXRecordDecl *Record,
+ const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) {
+ if (Bases.count(Record->getCanonicalDecl()))
+ return false;
+
+ RecordDecl *RD = Record->getDefinition();
+ if (!RD) return false;
+ Record = cast<CXXRecordDecl>(RD);
+
+ for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(),
+ E = Record->bases_end(); I != E; ++I) {
+ CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType());
+ CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>();
+ if (!BaseRT) return false;
+
+ CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl());
+ if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases))
+ return false;
+ }
+
+ return true;
+}
+
+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 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,
+ Scope *CurScope,
+ 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;
+ llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes;
+ for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) {
+ NamedDecl *D = *I;
+
+ if (D->isCXXInstanceMember()) {
+ if (dyn_cast<FieldDecl>(D))
+ isField = true;
+
+ 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;
+
+ bool IsCXX11UnevaluatedField = false;
+ if (SemaRef.getLangOpts().CPlusPlus0x && isField) {
+ // 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.
+ const Sema::ExpressionEvaluationContextRecord& record
+ = SemaRef.ExprEvalContexts.back();
+ if (record.Context == Sema::Unevaluated)
+ IsCXX11UnevaluatedField = true;
+ }
+
+ // 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 IsCXX11UnevaluatedField ? IMA_Field_Uneval_Context
+ : 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() &&
+ contextClass->isProvablyNotDerivedFrom(R.getNamingClass()))
+ return hasNonInstance ? IMA_Mixed_Unrelated :
+ IsCXX11UnevaluatedField ? IMA_Field_Uneval_Context :
+ IMA_Error_Unrelated;
+
+ // 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 :
+ IsCXX11UnevaluatedField ? IMA_Field_Uneval_Context :
+ 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());
+
+ DeclContext *FunctionLevelDC = SemaRef.getFunctionLevelDeclContext();
+ CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FunctionLevelDC);
+ CXXRecordDecl *ContextClass = Method ? Method->getParent() : 0;
+ 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) {
+ switch (ClassifyImplicitMemberAccess(*this, CurScope, R)) {
+ case IMA_Instance:
+ return BuildImplicitMemberExpr(SS, TemplateKWLoc, R, TemplateArgs, true);
+
+ case IMA_Mixed:
+ case IMA_Mixed_Unrelated:
+ case IMA_Unresolved:
+ return BuildImplicitMemberExpr(SS, TemplateKWLoc, R, TemplateArgs, false);
+
+ case IMA_Field_Uneval_Context:
+ Diag(R.getNameLoc(), diag::warn_cxx98_compat_non_static_member_use)
+ << R.getLookupNameInfo().getName();
+ // Fall through.
+ case IMA_Static:
+ case IMA_Mixed_StaticContext:
+ case IMA_Unresolved_StaticContext:
+ if (TemplateArgs || TemplateKWLoc.isValid())
+ return BuildTemplateIdExpr(SS, TemplateKWLoc, R, false, TemplateArgs);
+ return 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");
+}
+
+/// 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';
+
+ 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) {
+ do {
+ if (HasIndex[Idx]) HasRepeated = true;
+ HasIndex[Idx] = true;
+ compStr++;
+ } while (*compStr && (Idx = vecType->getPointAccessorIdx(*compStr)) != -1);
+ } 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++)) {
+ S.Diag(OpLoc, diag::err_ext_vector_component_exceeds_length)
+ << baseType << 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_RValue;
+
+ 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.ExternalSource),
+ 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))
+ return PD;
+ if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel))
+ return OMD;
+
+ for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(),
+ E = PDecl->protocol_end(); I != E; ++I) {
+ if (Decl *D = FindGetterSetterNameDeclFromProtocolList(*I, Member, Sel,
+ Context))
+ return D;
+ }
+ return 0;
+}
+
+static Decl *FindGetterSetterNameDecl(const ObjCObjectPointerType *QIdTy,
+ IdentifierInfo *Member,
+ const Selector &Sel,
+ ASTContext &Context) {
+ // Check protocols on qualified interfaces.
+ Decl *GDecl = 0;
+ for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(),
+ E = QIdTy->qual_end(); I != E; ++I) {
+ if (Member)
+ if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) {
+ 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 (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(),
+ E = QIdTy->qual_end(); I != E; ++I) {
+ // 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().ObjC1 ||
+ PT->getPointeeType()->isRecordType())) {
+ assert(BaseExpr && "cannot happen with implicit member accesses");
+ Diag(NameInfo.getLoc(), diag::err_typecheck_member_reference_struct_union)
+ << BaseType << BaseExpr->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 Owned(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) {
+ const RecordType *BaseRT = BaseType->getAs<RecordType>();
+ if (!BaseRT) {
+ // We can't check this yet because the base type is still
+ // dependent.
+ assert(BaseType->isDependentType());
+ return false;
+ }
+ CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl());
+
+ 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();
+ while (DC->isTransparentContext())
+ DC = DC->getParent();
+
+ if (!DC->isRecord())
+ continue;
+
+ llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord;
+ MemberRecord.insert(cast<CXXRecordDecl>(DC)->getCanonicalDecl());
+
+ if (!IsProvablyNotDerivedFrom(*this, BaseRecord, 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.
+class RecordMemberExprValidatorCCC : public CorrectionCandidateCallback {
+ public:
+ virtual bool ValidateCandidate(const TypoCorrection &candidate) {
+ NamedDecl *ND = candidate.getCorrectionDecl();
+ return ND && (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND));
+ }
+};
+
+}
+
+static bool
+LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R,
+ SourceRange BaseRange, const RecordType *RTy,
+ SourceLocation OpLoc, CXXScopeSpec &SS,
+ bool HasTemplateArgs) {
+ RecordDecl *RDecl = RTy->getDecl();
+ if (!SemaRef.isThisOutsideMemberFunctionBody(QualType(RTy, 0)) &&
+ SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0),
+ SemaRef.PDiag(diag::err_typecheck_incomplete_tag)
+ << BaseRange))
+ return true;
+
+ if (HasTemplateArgs) {
+ // LookupTemplateName doesn't expect these both to exist simultaneously.
+ QualType ObjectType = SS.isSet() ? QualType() : QualType(RTy, 0);
+
+ bool MOUS;
+ SemaRef.LookupTemplateName(R, 0, SS, ObjectType, false, MOUS);
+ return false;
+ }
+
+ 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);
+
+ if (!R.empty())
+ return false;
+
+ // We didn't find anything with the given name, so try to correct
+ // for typos.
+ DeclarationName Name = R.getLookupName();
+ RecordMemberExprValidatorCCC Validator;
+ TypoCorrection Corrected = SemaRef.CorrectTypo(R.getLookupNameInfo(),
+ R.getLookupKind(), NULL,
+ &SS, Validator, DC);
+ R.clear();
+ if (NamedDecl *ND = Corrected.getCorrectionDecl()) {
+ std::string CorrectedStr(
+ Corrected.getAsString(SemaRef.getLangOpts()));
+ std::string CorrectedQuotedStr(
+ Corrected.getQuoted(SemaRef.getLangOpts()));
+ R.setLookupName(Corrected.getCorrection());
+ R.addDecl(ND);
+ SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest)
+ << Name << DC << CorrectedQuotedStr << SS.getRange()
+ << FixItHint::CreateReplacement(R.getNameLoc(), CorrectedStr);
+ SemaRef.Diag(ND->getLocation(), diag::note_previous_decl)
+ << ND->getDeclName();
+ }
+
+ return false;
+}
+
+ExprResult
+Sema::BuildMemberReferenceExpr(Expr *Base, QualType BaseType,
+ SourceLocation OpLoc, bool IsArrow,
+ CXXScopeSpec &SS,
+ SourceLocation TemplateKWLoc,
+ NamedDecl *FirstQualifierInScope,
+ const DeclarationNameInfo &NameInfo,
+ const TemplateArgumentListInfo *TemplateArgs) {
+ 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) {
+ QualType RecordTy = BaseType;
+ if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType();
+ if (LookupMemberExprInRecord(*this, R, SourceRange(),
+ RecordTy->getAs<RecordType>(),
+ OpLoc, SS, TemplateArgs != 0))
+ return ExprError();
+
+ // Explicit member accesses.
+ } else {
+ ExprResult BaseResult = Owned(Base);
+ ExprResult Result =
+ LookupMemberExpr(R, BaseResult, IsArrow, OpLoc,
+ SS, /*ObjCImpDecl*/ 0, TemplateArgs != 0);
+
+ if (BaseResult.isInvalid())
+ return ExprError();
+ Base = BaseResult.take();
+
+ if (Result.isInvalid()) {
+ Owned(Base);
+ return ExprError();
+ }
+
+ if (Result.get())
+ return move(Result);
+
+ // LookupMemberExpr can modify Base, and thus change BaseType
+ BaseType = Base->getType();
+ }
+
+ return BuildMemberReferenceExpr(Base, BaseType,
+ OpLoc, IsArrow, SS, TemplateKWLoc,
+ FirstQualifierInScope, R, TemplateArgs);
+}
+
+static ExprResult
+BuildFieldReferenceExpr(Sema &S, Expr *BaseExpr, bool IsArrow,
+ const CXXScopeSpec &SS, FieldDecl *Field,
+ DeclAccessPair FoundDecl,
+ const DeclarationNameInfo &MemberNameInfo);
+
+ExprResult
+Sema::BuildAnonymousStructUnionMemberReference(const CXXScopeSpec &SS,
+ SourceLocation loc,
+ IndirectFieldDecl *indirectField,
+ Expr *baseObjectExpr,
+ SourceLocation opLoc) {
+ // First, build the expression that refers to the base object.
+
+ bool baseObjectIsPointer = false;
+ Qualifiers baseQuals;
+
+ // 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.take();
+ baseObjectIsPointer = false;
+ baseQuals = baseObjectExpr->getType().getQualifiers();
+
+ // Case 2: the base of the indirect field is a field and the user
+ // wrote a member expression.
+ } else if (baseObjectExpr) {
+ // The caller provided the base object expression. Determine
+ // whether its a pointer and whether it adds any qualifiers to the
+ // anonymous struct/union fields we're looking into.
+ QualType objectType = baseObjectExpr->getType();
+
+ if (const PointerType *ptr = objectType->getAs<PointerType>()) {
+ baseObjectIsPointer = true;
+ objectType = ptr->getPointeeType();
+ } else {
+ baseObjectIsPointer = false;
+ }
+ baseQuals = objectType.getQualifiers();
+
+ // Case 3: the base of the indirect field is a field and we should
+ // build an implicit member access.
+ } else {
+ // We've found a member of an anonymous struct/union that is
+ // inside a non-anonymous struct/union, so in a well-formed
+ // program our base object expression is "this".
+ QualType ThisTy = getCurrentThisType();
+ if (ThisTy.isNull()) {
+ Diag(loc, diag::err_invalid_member_use_in_static_method)
+ << indirectField->getDeclName();
+ return ExprError();
+ }
+
+ // Our base object expression is "this".
+ CheckCXXThisCapture(loc);
+ baseObjectExpr
+ = new (Context) CXXThisExpr(loc, ThisTy, /*isImplicit=*/ true);
+ baseObjectIsPointer = true;
+ baseQuals = ThisTy->castAs<PointerType>()->getPointeeType().getQualifiers();
+ }
+
+ // 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();
+
+ // Build the first member access in the chain with full information.
+ if (!baseVariable) {
+ FieldDecl *field = cast<FieldDecl>(*FI);
+
+ // FIXME: use the real found-decl info!
+ DeclAccessPair foundDecl = DeclAccessPair::make(field, field->getAccess());
+
+ // Make a nameInfo that properly uses the anonymous name.
+ DeclarationNameInfo memberNameInfo(field->getDeclName(), loc);
+
+ result = BuildFieldReferenceExpr(*this, result, baseObjectIsPointer,
+ EmptySS, field, foundDecl,
+ memberNameInfo).take();
+ baseObjectIsPointer = false;
+
+ // FIXME: check qualified member access
+ }
+
+ // 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 foundDecl = DeclAccessPair::make(field, field->getAccess());
+
+ result = BuildFieldReferenceExpr(*this, result, /*isarrow*/ false,
+ (FI == FEnd? SS : EmptySS), field,
+ foundDecl, memberNameInfo).take();
+ }
+
+ return Owned(result);
+}
+
+/// \brief Build a MemberExpr AST node.
+static MemberExpr *BuildMemberExpr(Sema &SemaRef,
+ ASTContext &C, Expr *Base, bool isArrow,
+ const CXXScopeSpec &SS,
+ SourceLocation TemplateKWLoc,
+ ValueDecl *Member,
+ DeclAccessPair FoundDecl,
+ const DeclarationNameInfo &MemberNameInfo,
+ QualType Ty,
+ ExprValueKind VK, ExprObjectKind OK,
+ const TemplateArgumentListInfo *TemplateArgs = 0) {
+ assert((!isArrow || Base->isRValue()) && "-> base must be a pointer rvalue");
+ MemberExpr *E =
+ MemberExpr::Create(C, Base, isArrow, SS.getWithLocInContext(C),
+ TemplateKWLoc, Member, FoundDecl, MemberNameInfo,
+ TemplateArgs, Ty, VK, OK);
+ SemaRef.MarkMemberReferenced(E);
+ return E;
+}
+
+ExprResult
+Sema::BuildMemberReferenceExpr(Expr *BaseExpr, QualType BaseExprType,
+ SourceLocation OpLoc, bool IsArrow,
+ const CXXScopeSpec &SS,
+ SourceLocation TemplateKWLoc,
+ NamedDecl *FirstQualifierInScope,
+ LookupResult &R,
+ const TemplateArgumentListInfo *TemplateArgs,
+ bool SuppressQualifierCheck) {
+ QualType BaseType = BaseExprType;
+ if (IsArrow) {
+ assert(BaseType->isPointerType());
+ BaseType = BaseType->castAs<PointerType>()->getPointeeType();
+ }
+ R.setBaseObjectType(BaseType);
+
+ const DeclarationNameInfo &MemberNameInfo = R.getLookupNameInfo();
+ DeclarationName MemberName = MemberNameInfo.getName();
+ SourceLocation MemberLoc = MemberNameInfo.getLoc();
+
+ if (R.isAmbiguous())
+ return ExprError();
+
+ if (R.empty()) {
+ // Rederive where we looked up.
+ DeclContext *DC = (SS.isSet()
+ ? computeDeclContext(SS, false)
+ : BaseType->getAs<RecordType>()->getDecl());
+
+ 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 Owned(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())
+ return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), MemberDecl);
+
+ SourceLocation Loc = R.getNameLoc();
+ if (SS.getRange().isValid())
+ Loc = SS.getRange().getBegin();
+ CheckCXXThisCapture(Loc);
+ BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true);
+ }
+
+ bool ShouldCheckUse = true;
+ if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) {
+ // Don't diagnose the use of a virtual member function unless it's
+ // explicitly qualified.
+ if (MD->isVirtual() && !SS.isSet())
+ ShouldCheckUse = false;
+ }
+
+ // Check the use of this member.
+ if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) {
+ Owned(BaseExpr);
+ return ExprError();
+ }
+
+ if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl))
+ return BuildFieldReferenceExpr(*this, BaseExpr, IsArrow,
+ SS, FD, FoundDecl, 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,
+ BaseExpr, OpLoc);
+
+ if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) {
+ return Owned(BuildMemberExpr(*this, Context, BaseExpr, IsArrow, SS,
+ TemplateKWLoc, Var, FoundDecl, MemberNameInfo,
+ Var->getType().getNonReferenceType(),
+ VK_LValue, OK_Ordinary));
+ }
+
+ if (CXXMethodDecl *MemberFn = dyn_cast<CXXMethodDecl>(MemberDecl)) {
+ ExprValueKind valueKind;
+ QualType type;
+ if (MemberFn->isInstance()) {
+ valueKind = VK_RValue;
+ type = Context.BoundMemberTy;
+ } else {
+ valueKind = VK_LValue;
+ type = MemberFn->getType();
+ }
+
+ return Owned(BuildMemberExpr(*this, Context, BaseExpr, IsArrow, SS,
+ TemplateKWLoc, MemberFn, FoundDecl,
+ MemberNameInfo, type, valueKind,
+ OK_Ordinary));
+ }
+ assert(!isa<FunctionDecl>(MemberDecl) && "member function not C++ method?");
+
+ if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) {
+ return Owned(BuildMemberExpr(*this, Context, BaseExpr, IsArrow, SS,
+ TemplateKWLoc, Enum, FoundDecl, MemberNameInfo,
+ Enum->getType(), VK_RValue, OK_Ordinary));
+ }
+
+ Owned(BaseExpr);
+
+ // 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() != 0)
+ return false;
+
+ base = S.ImpCastExprToType(base.take(), 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++.
+ExprResult
+Sema::LookupMemberExpr(LookupResult &R, ExprResult &BaseExpr,
+ bool &IsArrow, SourceLocation OpLoc,
+ CXXScopeSpec &SS,
+ Decl *ObjCImpDecl, bool HasTemplateArgs) {
+ assert(BaseExpr.get() && "no base expression");
+
+ // Perform default conversions.
+ BaseExpr = PerformMemberExprBaseConversion(BaseExpr.take(), 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.
+ 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 {
+ 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>()) {
+ if (LookupMemberExprInRecord(*this, R, BaseExpr.get()->getSourceRange(),
+ RTy, OpLoc, SS, HasTemplateArgs))
+ return ExprError();
+
+ // Returning valid-but-null is how we indicate to the caller that
+ // the lookup result was filled in.
+ return Owned((Expr*) 0);
+ }
+
+ // Handle ivar access to Objective-C objects.
+ if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>()) {
+ if (!SS.isEmpty() && !SS.isInvalid()) {
+ 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 (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.ghjg
+ if (OTy->isObjCId() && Member->isStr("isa")) {
+ Diag(MemberLoc, diag::warn_objc_isa_use);
+ return Owned(new (Context) ObjCIsaExpr(BaseExpr.take(), IsArrow, MemberLoc,
+ Context.getObjCClassType()));
+ }
+
+ if (ShouldTryAgainWithRedefinitionType(*this, BaseExpr))
+ return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS,
+ ObjCImpDecl, HasTemplateArgs);
+ goto fail;
+ }
+
+ if (RequireCompleteType(OpLoc, BaseType,
+ PDiag(diag::err_typecheck_incomplete_tag)
+ << BaseExpr.get()->getSourceRange()))
+ return ExprError();
+
+ ObjCInterfaceDecl *ClassDeclared = 0;
+ 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 = CorrectTypo(R.getLookupNameInfo(),
+ LookupMemberName, NULL, NULL,
+ Validator, IDecl)) {
+ IV = Corrected.getCorrectionDeclAs<ObjCIvarDecl>();
+ Diag(R.getNameLoc(),
+ diag::err_typecheck_member_reference_ivar_suggest)
+ << IDecl->getDeclName() << MemberName << IV->getDeclName()
+ << FixItHint::CreateReplacement(R.getNameLoc(),
+ IV->getNameAsString());
+ Diag(IV->getLocation(), diag::note_previous_decl)
+ << IV->getDeclName();
+
+ // Figure out the class that declares the ivar.
+ assert(!ClassDeclared);
+ Decl *D = cast<Decl>(IV->getDeclContext());
+ if (ObjCCategoryDecl *CAT = dyn_cast<ObjCCategoryDecl>(D))
+ D = CAT->getClassInterface();
+ ClassDeclared = cast<ObjCInterfaceDecl>(D);
+ } else {
+ if (IsArrow && IDecl->FindPropertyDeclaration(Member)) {
+ Diag(MemberLoc,
+ diag::err_property_found_suggest)
+ << Member << BaseExpr.get()->getType()
+ << FixItHint::CreateReplacement(OpLoc, ".");
+ return ExprError();
+ }
+
+ 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 (DiagnoseUseOfDecl(IV, MemberLoc))
+ return ExprError();
+ if (IV->getAccessControl() != ObjCIvarDecl::Public &&
+ IV->getAccessControl() != ObjCIvarDecl::Package) {
+ ObjCInterfaceDecl *ClassOfMethodDecl = 0;
+ if (ObjCMethodDecl *MD = getCurMethodDecl())
+ ClassOfMethodDecl = MD->getClassInterface();
+ else if (ObjCImpDecl && 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 (!getLangOpts().DebuggerSupport) {
+ if (IV->getAccessControl() == ObjCIvarDecl::Private) {
+ if (!declaresSameEntity(ClassDeclared, IDecl) ||
+ !declaresSameEntity(ClassOfMethodDecl, ClassDeclared))
+ Diag(MemberLoc, diag::error_private_ivar_access)
+ << IV->getDeclName();
+ } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl))
+ // @protected
+ Diag(MemberLoc, diag::error_protected_ivar_access)
+ << IV->getDeclName();
+ }
+ }
+ if (getLangOpts().ObjCAutoRefCount) {
+ 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)
+ Diag(DE->getLocation(), diag::error_arc_weak_ivar_access);
+ }
+
+ return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(),
+ MemberLoc, BaseExpr.take(),
+ IsArrow));
+ }
+
+ // Objective-C property access.
+ const ObjCObjectPointerType *OPT;
+ if (!IsArrow && (OPT = BaseType->getAs<ObjCObjectPointerType>())) {
+ if (!SS.isEmpty() && !SS.isInvalid()) {
+ 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 = DefaultLvalueConversion(BaseExpr.take());
+ if (BaseExpr.isInvalid())
+ return ExprError();
+
+ assert(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 = PP.getSelectorTable().getNullarySelector(Member);
+ if (Decl *PMDecl = FindGetterSetterNameDecl(OPT, Member, Sel, Context)) {
+ if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) {
+ // Check the use of this declaration
+ if (DiagnoseUseOfDecl(PD, MemberLoc))
+ return ExprError();
+
+ return Owned(new (Context) ObjCPropertyRefExpr(PD,
+ Context.PseudoObjectTy,
+ VK_LValue,
+ OK_ObjCProperty,
+ MemberLoc,
+ BaseExpr.take()));
+ }
+
+ if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) {
+ // Check the use of this method.
+ if (DiagnoseUseOfDecl(OMD, MemberLoc))
+ return ExprError();
+ Selector SetterSel =
+ SelectorTable::constructSetterName(PP.getIdentifierTable(),
+ PP.getSelectorTable(), Member);
+ ObjCMethodDecl *SMD = 0;
+ if (Decl *SDecl = FindGetterSetterNameDecl(OPT, /*Property id*/0,
+ SetterSel, Context))
+ SMD = dyn_cast<ObjCMethodDecl>(SDecl);
+
+ return Owned(new (Context) ObjCPropertyRefExpr(OMD, SMD,
+ Context.PseudoObjectTy,
+ VK_LValue, OK_ObjCProperty,
+ MemberLoc, BaseExpr.take()));
+ }
+ }
+ // Use of id.member can only be for a property reference. Do not
+ // use the 'id' redefinition in this case.
+ if (IsArrow && ShouldTryAgainWithRedefinitionType(*this, BaseExpr))
+ return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS,
+ ObjCImpDecl, HasTemplateArgs);
+
+ return ExprError(Diag(MemberLoc, diag::err_property_not_found)
+ << MemberName << BaseType);
+ }
+
+ // 'Class', unqualified only.
+ if (OT->isObjCClass()) {
+ // Only works in a method declaration (??!).
+ ObjCMethodDecl *MD = getCurMethodDecl();
+ if (!MD) {
+ if (ShouldTryAgainWithRedefinitionType(*this, BaseExpr))
+ return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS,
+ ObjCImpDecl, HasTemplateArgs);
+
+ goto fail;
+ }
+
+ // Also must look for a getter name which uses property syntax.
+ Selector Sel = PP.getSelectorTable().getNullarySelector(Member);
+ ObjCInterfaceDecl *IFace = MD->getClassInterface();
+ ObjCMethodDecl *Getter;
+ if ((Getter = IFace->lookupClassMethod(Sel))) {
+ // Check the use of this method.
+ if (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::constructSetterName(PP.getIdentifierTable(),
+ 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);
+ }
+ // Look through local category implementations associated with the class.
+ if (!Setter)
+ Setter = IFace->getCategoryClassMethod(SetterSel);
+
+ if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc))
+ return ExprError();
+
+ if (Getter || Setter) {
+ return Owned(new (Context) ObjCPropertyRefExpr(Getter, Setter,
+ Context.PseudoObjectTy,
+ VK_LValue, OK_ObjCProperty,
+ MemberLoc, BaseExpr.take()));
+ }
+
+ if (ShouldTryAgainWithRedefinitionType(*this, BaseExpr))
+ return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS,
+ ObjCImpDecl, HasTemplateArgs);
+
+ return ExprError(Diag(MemberLoc, diag::err_property_not_found)
+ << MemberName << BaseType);
+ }
+
+ // Normal property access.
+ return 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 = (IsArrow ? VK_LValue : BaseExpr.get()->getValueKind());
+ QualType ret = CheckExtVectorComponent(*this, BaseType, VK, OpLoc,
+ Member, MemberLoc);
+ if (ret.isNull())
+ return ExprError();
+
+ return Owned(new (Context) ExtVectorElementExpr(ret, VK, BaseExpr.take(),
+ *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) &&
+ !Context.getObjCSelRedefinitionType()->isObjCSelType()) {
+ BaseExpr = ImpCastExprToType(BaseExpr.take(),
+ Context.getObjCSelRedefinitionType(),
+ CK_BitCast);
+ return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS,
+ ObjCImpDecl, HasTemplateArgs);
+ }
+
+ // 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) {
+ 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(R, BaseExpr, IsArrow, OpLoc, SS,
+ ObjCImpDecl, HasTemplateArgs);
+ }
+ }
+
+ // If the user is trying to apply -> or . to a function name, it's probably
+ // because they forgot parentheses to call that function.
+ if (tryToRecoverWithCall(BaseExpr,
+ PDiag(diag::err_member_reference_needs_call),
+ /*complain*/ false,
+ IsArrow ? &isPointerToRecordType : &isRecordType)) {
+ if (BaseExpr.isInvalid())
+ return ExprError();
+ BaseExpr = DefaultFunctionArrayConversion(BaseExpr.take());
+ return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS,
+ ObjCImpDecl, HasTemplateArgs);
+ }
+
+ Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union)
+ << BaseType << BaseExpr.get()->getSourceRange();
+
+ 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 HasTrailingLParen whether the next token is '(', which
+/// is used to diagnose mis-uses of special members that can
+/// only be called
+/// \param ObjCImpDecl the current ObjC @implementation decl;
+/// this is an ugly hack around the fact that ObjC @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,
+ bool HasTrailingLParen) {
+ if (SS.isSet() && SS.isInvalid())
+ return ExprError();
+
+ // Warn about the explicit constructor calls Microsoft extension.
+ if (getLangOpts().MicrosoftExt &&
+ Id.getKind() == UnqualifiedId::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() ? 0 : FindFirstQualifierInScope(S,
+ static_cast<NestedNameSpecifier*>(SS.getScopeRep())));
+
+ // This is a postfix expression, so get rid of ParenListExprs.
+ ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base);
+ if (Result.isInvalid()) return ExprError();
+ Base = Result.take();
+
+ if (Base->getType()->isDependentType() || Name.isDependentName() ||
+ isDependentScopeSpecifier(SS)) {
+ Result = ActOnDependentMemberExpr(Base, Base->getType(),
+ IsArrow, OpLoc,
+ SS, TemplateKWLoc, FirstQualifierInScope,
+ NameInfo, TemplateArgs);
+ } else {
+ LookupResult R(*this, NameInfo, LookupMemberName);
+ ExprResult BaseResult = Owned(Base);
+ Result = LookupMemberExpr(R, BaseResult, IsArrow, OpLoc,
+ SS, ObjCImpDecl, TemplateArgs != 0);
+ if (BaseResult.isInvalid())
+ return ExprError();
+ Base = BaseResult.take();
+
+ if (Result.isInvalid()) {
+ Owned(Base);
+ return ExprError();
+ }
+
+ if (Result.get()) {
+ // The only way a reference to a destructor can be used is to
+ // immediately call it, which falls into this case. If the
+ // next token is not a '(', produce a diagnostic and build the
+ // call now.
+ if (!HasTrailingLParen &&
+ Id.getKind() == UnqualifiedId::IK_DestructorName)
+ return DiagnoseDtorReference(NameInfo.getLoc(), Result.get());
+
+ return move(Result);
+ }
+
+ Result = BuildMemberReferenceExpr(Base, Base->getType(),
+ OpLoc, IsArrow, SS, TemplateKWLoc,
+ FirstQualifierInScope, R, TemplateArgs);
+ }
+
+ return move(Result);
+}
+
+static ExprResult
+BuildFieldReferenceExpr(Sema &S, Expr *BaseExpr, bool IsArrow,
+ 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_RValue;
+ }
+ if (VK != VK_RValue && 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->getAs<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
+ = S.Context.getCanonicalType(MemberType).getQualifiers();
+
+ // TR 18037 does not allow fields to be declared with address spaces.
+ assert(!MemberQuals.hasAddressSpace());
+
+ Qualifiers Combined = BaseQuals + MemberQuals;
+ if (Combined != MemberQuals)
+ MemberType = S.Context.getQualifiedType(MemberType, Combined);
+ }
+
+ ExprResult Base =
+ S.PerformObjectMemberConversion(BaseExpr, SS.getScopeRep(),
+ FoundDecl, Field);
+ if (Base.isInvalid())
+ return ExprError();
+ return S.Owned(BuildMemberExpr(S, S.Context, Base.take(), IsArrow, SS,
+ /*TemplateKWLoc=*/SourceLocation(),
+ Field, FoundDecl, 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) {
+ assert(!R.empty() && !R.isAmbiguous());
+
+ SourceLocation loc = R.getNameLoc();
+
+ // We may have found a field within an anonymous union or struct
+ // (C++ [class.union]).
+ // FIXME: template-ids inside anonymous structs?
+ if (IndirectFieldDecl *FD = R.getAsSingle<IndirectFieldDecl>())
+ return BuildAnonymousStructUnionMemberReference(SS, R.getNameLoc(), FD);
+
+ // If this is known to be an instance access, go ahead and build an
+ // implicit 'this' expression now.
+ // 'this' expression now.
+ QualType ThisTy = getCurrentThisType();
+ assert(!ThisTy.isNull() && "didn't correctly pre-flight capture of 'this'");
+
+ Expr *baseExpr = 0; // null signifies implicit access
+ if (IsKnownInstance) {
+ SourceLocation Loc = R.getNameLoc();
+ if (SS.getRange().isValid())
+ Loc = SS.getRange().getBegin();
+ CheckCXXThisCapture(Loc);
+ baseExpr = new (Context) CXXThisExpr(loc, ThisTy, /*isImplicit=*/true);
+ }
+
+ return BuildMemberReferenceExpr(baseExpr, ThisTy,
+ /*OpLoc*/ SourceLocation(),
+ /*IsArrow*/ true,
+ SS, TemplateKWLoc,
+ /*FirstQualifierInScope*/ 0,
+ R, TemplateArgs);
+}