diff options
Diffstat (limited to 'lib/Sema/SemaCXXCast.cpp')
| -rw-r--r-- | lib/Sema/SemaCXXCast.cpp | 162 |
1 files changed, 122 insertions, 40 deletions
diff --git a/lib/Sema/SemaCXXCast.cpp b/lib/Sema/SemaCXXCast.cpp index e46ad5b..d053d5a 100644 --- a/lib/Sema/SemaCXXCast.cpp +++ b/lib/Sema/SemaCXXCast.cpp @@ -63,7 +63,8 @@ static void CheckDynamicCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, CastKind &Kind, CXXCastPath &BasePath); -static bool CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType); +static bool CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType, + bool CheckCVR, bool CheckObjCLifetime); // The Try functions attempt a specific way of casting. If they succeed, they // return TC_Success. If their way of casting is not appropriate for the given @@ -109,12 +110,14 @@ static TryCastResult TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExp CXXCastPath &BasePath); static TryCastResult TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, - QualType DestType, bool CStyle, + QualType DestType, + Sema::CheckedConversionKind CCK, const SourceRange &OpRange, unsigned &msg, CastKind &Kind); static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr, - QualType DestType, bool CStyle, + QualType DestType, + Sema::CheckedConversionKind CCK, const SourceRange &OpRange, unsigned &msg, CastKind &Kind, @@ -131,17 +134,23 @@ static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr, /// ActOnCXXNamedCast - Parse {dynamic,static,reinterpret,const}_cast's. ExprResult Sema::ActOnCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind, - SourceLocation LAngleBracketLoc, ParsedType Ty, + SourceLocation LAngleBracketLoc, Declarator &D, SourceLocation RAngleBracketLoc, SourceLocation LParenLoc, Expr *E, SourceLocation RParenLoc) { - - TypeSourceInfo *DestTInfo; - QualType DestType = GetTypeFromParser(Ty, &DestTInfo); - if (!DestTInfo) - DestTInfo = Context.getTrivialTypeSourceInfo(DestType, SourceLocation()); - return BuildCXXNamedCast(OpLoc, Kind, DestTInfo, move(E), + assert(!D.isInvalidType()); + + TypeSourceInfo *TInfo = GetTypeForDeclaratorCast(D, E->getType()); + if (D.isInvalidType()) + return ExprError(); + + if (getLangOptions().CPlusPlus) { + // Check that there are no default arguments (C++ only). + CheckExtraCXXDefaultArguments(D); + } + + return BuildCXXNamedCast(OpLoc, Kind, TInfo, move(E), SourceRange(LAngleBracketLoc, RAngleBracketLoc), SourceRange(LParenLoc, RParenLoc)); } @@ -248,8 +257,10 @@ static bool tryDiagnoseOverloadedCast(Sema &S, CastType CT, InitializedEntity entity = InitializedEntity::InitializeTemporary(destType); InitializationKind initKind - = InitializationKind::CreateCast(/*type range?*/ range, - (CT == CT_CStyle || CT == CT_Functional)); + = (CT == CT_CStyle)? InitializationKind::CreateCStyleCast(range.getBegin(), + range) + : (CT == CT_Functional)? InitializationKind::CreateFunctionalCast(range) + : InitializationKind::CreateCast(/*type range?*/ range); InitializationSequence sequence(S, entity, initKind, &src, 1); assert(sequence.Failed() && "initialization succeeded on second try?"); @@ -373,8 +384,19 @@ static bool UnwrapDissimilarPointerTypes(QualType& T1, QualType& T2) { /// DestType casts away constness as defined in C++ 5.2.11p8ff. This is used by /// the cast checkers. Both arguments must denote pointer (possibly to member) /// types. +/// +/// \param CheckCVR Whether to check for const/volatile/restrict qualifiers. +/// +/// \param CheckObjCLifetime Whether to check Objective-C lifetime qualifiers. static bool -CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType) { +CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType, + bool CheckCVR, bool CheckObjCLifetime) { + // If the only checking we care about is for Objective-C lifetime qualifiers, + // and we're not in ARC mode, there's nothing to check. + if (!CheckCVR && CheckObjCLifetime && + !Self.Context.getLangOptions().ObjCAutoRefCount) + return false; + // Casting away constness is defined in C++ 5.2.11p8 with reference to // C++ 4.4. We piggyback on Sema::IsQualificationConversion for this, since // the rules are non-trivial. So first we construct Tcv *...cv* as described @@ -394,13 +416,23 @@ CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType) { // purpose of this check, because other qualifiers (address spaces, // Objective-C GC, etc.) are part of the type's identity. while (UnwrapDissimilarPointerTypes(UnwrappedSrcType, UnwrappedDestType)) { - Qualifiers SrcQuals; + // Determine the relevant qualifiers at this level. + Qualifiers SrcQuals, DestQuals; Self.Context.getUnqualifiedArrayType(UnwrappedSrcType, SrcQuals); - cv1.push_back(Qualifiers::fromCVRMask(SrcQuals.getCVRQualifiers())); - - Qualifiers DestQuals; Self.Context.getUnqualifiedArrayType(UnwrappedDestType, DestQuals); - cv2.push_back(Qualifiers::fromCVRMask(DestQuals.getCVRQualifiers())); + + Qualifiers RetainedSrcQuals, RetainedDestQuals; + if (CheckCVR) { + RetainedSrcQuals.setCVRQualifiers(SrcQuals.getCVRQualifiers()); + RetainedDestQuals.setCVRQualifiers(DestQuals.getCVRQualifiers()); + } + + if (CheckObjCLifetime && + !DestQuals.compatiblyIncludesObjCLifetime(SrcQuals)) + return true; + + cv1.push_back(RetainedSrcQuals); + cv2.push_back(RetainedDestQuals); } if (cv1.empty()) return false; @@ -420,8 +452,10 @@ CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType) { } // Test if they're compatible. + bool ObjCLifetimeConversion; return SrcConstruct != DestConstruct && - !Self.IsQualificationConversion(SrcConstruct, DestConstruct, false); + !Self.IsQualificationConversion(SrcConstruct, DestConstruct, false, + ObjCLifetimeConversion); } /// CheckDynamicCast - Check that a dynamic_cast\<DestType\>(SrcExpr) is valid. @@ -595,9 +629,10 @@ CheckReinterpretCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, } unsigned msg = diag::err_bad_cxx_cast_generic; - if (TryReinterpretCast(Self, SrcExpr, DestType, /*CStyle*/false, OpRange, - msg, Kind) - != TC_Success && msg != 0) + TryCastResult tcr = + TryReinterpretCast(Self, SrcExpr, DestType, + /*CStyle*/false, OpRange, msg, Kind); + if (tcr != TC_Success && msg != 0) { if (SrcExpr.isInvalid()) // if conversion failed, don't report another error return; @@ -611,7 +646,12 @@ CheckReinterpretCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, } else { diagnoseBadCast(Self, msg, CT_Reinterpret, OpRange, SrcExpr.get(), DestType); } - } + } else if (tcr == TC_Success && Self.getLangOptions().ObjCAutoRefCount) { + Expr *Exp = SrcExpr.get(); + // Note that Exp does not change with CCK_OtherCast cast type + Self.CheckObjCARCConversion(OpRange, DestType, + Exp, Sema::CCK_OtherCast); + } } @@ -654,8 +694,10 @@ CheckStaticCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, } unsigned msg = diag::err_bad_cxx_cast_generic; - if (TryStaticCast(Self, SrcExpr, DestType, /*CStyle*/false, OpRange, msg, - Kind, BasePath) != TC_Success && msg != 0) { + TryCastResult tcr + = TryStaticCast(Self, SrcExpr, DestType, Sema::CCK_OtherCast, OpRange, msg, + Kind, BasePath); + if (tcr != TC_Success && msg != 0) { if (SrcExpr.isInvalid()) return; if (SrcExpr.get()->getType() == Self.Context.OverloadTy) { @@ -667,6 +709,15 @@ CheckStaticCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, } else { diagnoseBadCast(Self, msg, CT_Static, OpRange, SrcExpr.get(), DestType); } + } else if (tcr == TC_Success) { + if (Kind == CK_BitCast) + Self.CheckCastAlign(SrcExpr.get(), DestType, OpRange); + if (Self.getLangOptions().ObjCAutoRefCount) { + Expr *Exp = SrcExpr.get(); + // Note that Exp does not change with CCK_OtherCast cast type + Self.CheckObjCARCConversion(OpRange, DestType, + Exp, Sema::CCK_OtherCast); + } } else if (Kind == CK_BitCast) Self.CheckCastAlign(SrcExpr.get(), DestType, OpRange); @@ -676,10 +727,15 @@ CheckStaticCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, /// possible. If @p CStyle, ignore access restrictions on hierarchy casting /// and casting away constness. static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr, - QualType DestType, bool CStyle, + QualType DestType, + Sema::CheckedConversionKind CCK, const SourceRange &OpRange, unsigned &msg, CastKind &Kind, CXXCastPath &BasePath) { + // Determine whether we have the semantics of a C-style cast. + bool CStyle + = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast); + // The order the tests is not entirely arbitrary. There is one conversion // that can be handled in two different ways. Given: // struct A {}; @@ -715,7 +771,7 @@ static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr, // C++ 5.2.9p2: An expression e can be explicitly converted to a type T // [...] if the declaration "T t(e);" is well-formed, [...]. - tcr = TryStaticImplicitCast(Self, SrcExpr, DestType, CStyle, OpRange, msg, + tcr = TryStaticImplicitCast(Self, SrcExpr, DestType, CCK, OpRange, msg, Kind); if (SrcExpr.isInvalid()) return TC_Failed; @@ -792,10 +848,20 @@ static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr, QualType DestPointee = DestPointer->getPointeeType(); if (DestPointee->isIncompleteOrObjectType()) { // This is definitely the intended conversion, but it might fail due - // to a const violation. - if (!CStyle && !DestPointee.isAtLeastAsQualifiedAs(SrcPointee)) { - msg = diag::err_bad_cxx_cast_qualifiers_away; - return TC_Failed; + // to a qualifier violation. Note that we permit Objective-C lifetime + // and GC qualifier mismatches here. + if (!CStyle) { + Qualifiers DestPointeeQuals = DestPointee.getQualifiers(); + Qualifiers SrcPointeeQuals = SrcPointee.getQualifiers(); + DestPointeeQuals.removeObjCGCAttr(); + DestPointeeQuals.removeObjCLifetime(); + SrcPointeeQuals.removeObjCGCAttr(); + SrcPointeeQuals.removeObjCLifetime(); + if (DestPointeeQuals != SrcPointeeQuals && + !DestPointeeQuals.compatiblyIncludes(SrcPointeeQuals)) { + msg = diag::err_bad_cxx_cast_qualifiers_away; + return TC_Failed; + } } Kind = CK_BitCast; return TC_Success; @@ -845,6 +911,7 @@ TryLValueToRValueCast(Sema &Self, Expr *SrcExpr, QualType DestType, // FIXME: Should allow casting away constness if CStyle. bool DerivedToBase; bool ObjCConversion; + bool ObjCLifetimeConversion; QualType FromType = SrcExpr->getType(); QualType ToType = R->getPointeeType(); if (CStyle) { @@ -854,8 +921,9 @@ TryLValueToRValueCast(Sema &Self, Expr *SrcExpr, QualType DestType, if (Self.CompareReferenceRelationship(SrcExpr->getLocStart(), ToType, FromType, - DerivedToBase, ObjCConversion) < - Sema::Ref_Compatible_With_Added_Qualification) { + DerivedToBase, ObjCConversion, + ObjCLifetimeConversion) + < Sema::Ref_Compatible_With_Added_Qualification) { msg = diag::err_bad_lvalue_to_rvalue_cast; return TC_Failed; } @@ -1172,7 +1240,8 @@ TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExpr, QualType SrcType, /// @c static_cast if the declaration "T t(e);" is well-formed [...]. TryCastResult TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, - bool CStyle, const SourceRange &OpRange, unsigned &msg, + Sema::CheckedConversionKind CCK, + const SourceRange &OpRange, unsigned &msg, CastKind &Kind) { if (DestType->isRecordType()) { if (Self.RequireCompleteType(OpRange.getBegin(), DestType, @@ -1184,7 +1253,11 @@ TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, InitializedEntity Entity = InitializedEntity::InitializeTemporary(DestType); InitializationKind InitKind - = InitializationKind::CreateCast(/*FIXME:*/OpRange, CStyle); + = (CCK == Sema::CCK_CStyleCast) + ? InitializationKind::CreateCStyleCast(OpRange.getBegin(), OpRange) + : (CCK == Sema::CCK_FunctionalCast) + ? InitializationKind::CreateFunctionalCast(OpRange) + : InitializationKind::CreateCast(OpRange); Expr *SrcExprRaw = SrcExpr.get(); InitializationSequence InitSeq(Self, Entity, InitKind, &SrcExprRaw, 1); @@ -1193,7 +1266,8 @@ TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, QualType DestType, // There is no other way that works. // On the other hand, if we're checking a C-style cast, we've still got // the reinterpret_cast way. - + bool CStyle + = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast); if (InitSeq.Failed() && (CStyle || !DestType->isReferenceType())) return TC_NotApplicable; @@ -1428,7 +1502,8 @@ static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr, // constness. // A reinterpret_cast followed by a const_cast can, though, so in C-style, // we accept it. - if (!CStyle && CastsAwayConstness(Self, SrcType, DestType)) { + if (CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle, + /*CheckObjCLifetime=*/CStyle)) { msg = diag::err_bad_cxx_cast_qualifiers_away; return TC_Failed; } @@ -1543,7 +1618,8 @@ static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr, // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away constness. // The C-style cast operator can. - if (!CStyle && CastsAwayConstness(Self, SrcType, DestType)) { + if (CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle, + /*CheckObjCLifetime=*/CStyle)) { msg = diag::err_bad_cxx_cast_qualifiers_away; return TC_Failed; } @@ -1675,11 +1751,14 @@ Sema::CXXCheckCStyleCast(SourceRange R, QualType CastTy, ExprValueKind &VK, if (tcr == TC_Success) Kind = CK_NoOp; + Sema::CheckedConversionKind CCK + = FunctionalStyle? Sema::CCK_FunctionalCast + : Sema::CCK_CStyleCast; if (tcr == TC_NotApplicable) { // ... or if that is not possible, a static_cast, ignoring const, ... ExprResult CastExprRes = Owned(CastExpr); - tcr = TryStaticCast(*this, CastExprRes, CastTy, /*CStyle*/true, R, msg, - Kind, BasePath); + tcr = TryStaticCast(*this, CastExprRes, CastTy, CCK, R, msg, Kind, + BasePath); if (CastExprRes.isInvalid()) return ExprError(); CastExpr = CastExprRes.take(); @@ -1694,6 +1773,9 @@ Sema::CXXCheckCStyleCast(SourceRange R, QualType CastTy, ExprValueKind &VK, } } + if (getLangOptions().ObjCAutoRefCount && tcr == TC_Success) + CheckObjCARCConversion(R, CastTy, CastExpr, CCK); + if (tcr != TC_Success && msg != 0) { if (CastExpr->getType() == Context.OverloadTy) { DeclAccessPair Found; |
