diff options
Diffstat (limited to 'lib/Sema/SemaStmt.cpp')
| -rw-r--r-- | lib/Sema/SemaStmt.cpp | 638 |
1 files changed, 469 insertions, 169 deletions
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp index 0d1da4540eb3..5c72529caa8a 100644 --- a/lib/Sema/SemaStmt.cpp +++ b/lib/Sema/SemaStmt.cpp @@ -15,6 +15,7 @@ #include "clang/AST/ASTContext.h" #include "clang/AST/ASTDiagnostic.h" #include "clang/AST/CharUnits.h" +#include "clang/AST/CXXInheritance.h" #include "clang/AST/DeclObjC.h" #include "clang/AST/EvaluatedExprVisitor.h" #include "clang/AST/ExprCXX.h" @@ -23,12 +24,14 @@ #include "clang/AST/StmtCXX.h" #include "clang/AST/StmtObjC.h" #include "clang/AST/TypeLoc.h" +#include "clang/AST/TypeOrdering.h" #include "clang/Lex/Preprocessor.h" #include "clang/Sema/Initialization.h" #include "clang/Sema/Lookup.h" #include "clang/Sema/Scope.h" #include "clang/Sema/ScopeInfo.h" #include "llvm/ADT/ArrayRef.h" +#include "llvm/ADT/DenseMap.h" #include "llvm/ADT/STLExtras.h" #include "llvm/ADT/SmallPtrSet.h" #include "llvm/ADT/SmallString.h" @@ -236,7 +239,9 @@ void Sema::DiagnoseUnusedExprResult(const Stmt *S) { // is written in a macro body, only warn if it has the warn_unused_result // attribute. if (const Decl *FD = CE->getCalleeDecl()) { - if (FD->hasAttr<WarnUnusedResultAttr>()) { + const FunctionDecl *Func = dyn_cast<FunctionDecl>(FD); + if (Func ? Func->hasUnusedResultAttr() + : FD->hasAttr<WarnUnusedResultAttr>()) { Diag(Loc, diag::warn_unused_result) << R1 << R2; return; } @@ -265,10 +270,6 @@ void Sema::DiagnoseUnusedExprResult(const Stmt *S) { Diag(Loc, diag::warn_unused_result) << R1 << R2; return; } - if (MD->isPropertyAccessor()) { - Diag(Loc, diag::warn_unused_property_expr); - return; - } } } else if (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E)) { const Expr *Source = POE->getSyntacticForm(); @@ -687,26 +688,39 @@ static void checkCaseValue(Sema &S, SourceLocation Loc, const llvm::APSInt &Val, } } +typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl*>, 64> EnumValsTy; + /// Returns true if we should emit a diagnostic about this case expression not /// being a part of the enum used in the switch controlling expression. -static bool ShouldDiagnoseSwitchCaseNotInEnum(const ASTContext &Ctx, +static bool ShouldDiagnoseSwitchCaseNotInEnum(const Sema &S, const EnumDecl *ED, - const Expr *CaseExpr) { - // Don't warn if the 'case' expression refers to a static const variable of - // the enum type. - CaseExpr = CaseExpr->IgnoreParenImpCasts(); - if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CaseExpr)) { + const Expr *CaseExpr, + EnumValsTy::iterator &EI, + EnumValsTy::iterator &EIEnd, + const llvm::APSInt &Val) { + bool FlagType = ED->hasAttr<FlagEnumAttr>(); + + if (const DeclRefExpr *DRE = + dyn_cast<DeclRefExpr>(CaseExpr->IgnoreParenImpCasts())) { if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) { - if (!VD->hasGlobalStorage()) - return true; QualType VarType = VD->getType(); - if (!VarType.isConstQualified()) - return true; - QualType EnumType = Ctx.getTypeDeclType(ED); - if (Ctx.hasSameUnqualifiedType(EnumType, VarType)) + QualType EnumType = S.Context.getTypeDeclType(ED); + if (VD->hasGlobalStorage() && VarType.isConstQualified() && + S.Context.hasSameUnqualifiedType(EnumType, VarType)) return false; } } + + if (FlagType) { + return !S.IsValueInFlagEnum(ED, Val, false); + } else { + while (EI != EIEnd && EI->first < Val) + EI++; + + if (EI != EIEnd && EI->first == Val) + return false; + } + return true; } @@ -897,12 +911,12 @@ Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch, if (PrevString == CurrString) Diag(CaseVals[i].second->getLHS()->getLocStart(), diag::err_duplicate_case) << - (PrevString.empty() ? CaseValStr.str() : PrevString); + (PrevString.empty() ? StringRef(CaseValStr) : PrevString); else Diag(CaseVals[i].second->getLHS()->getLocStart(), diag::err_duplicate_case_differing_expr) << - (PrevString.empty() ? CaseValStr.str() : PrevString) << - (CurrString.empty() ? CaseValStr.str() : CurrString) << + (PrevString.empty() ? StringRef(CaseValStr) : PrevString) << + (CurrString.empty() ? StringRef(CaseValStr) : CurrString) << CaseValStr; Diag(CaseVals[i-1].second->getLHS()->getLocStart(), @@ -1046,8 +1060,6 @@ Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch, // If switch has default case, then ignore it. if (!CaseListIsErroneous && !HasConstantCond && ET) { const EnumDecl *ED = ET->getDecl(); - typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl*>, 64> - EnumValsTy; EnumValsTy EnumVals; // Gather all enum values, set their type and sort them, @@ -1058,57 +1070,48 @@ Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch, EnumVals.push_back(std::make_pair(Val, EDI)); } std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals); - EnumValsTy::iterator EIend = + auto EI = EnumVals.begin(), EIEnd = std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals); // See which case values aren't in enum. - EnumValsTy::const_iterator EI = EnumVals.begin(); for (CaseValsTy::const_iterator CI = CaseVals.begin(); - CI != CaseVals.end(); CI++) { - while (EI != EIend && EI->first < CI->first) - EI++; - if (EI == EIend || EI->first > CI->first) { - Expr *CaseExpr = CI->second->getLHS(); - if (ShouldDiagnoseSwitchCaseNotInEnum(Context, ED, CaseExpr)) - Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum) - << CondTypeBeforePromotion; - } + CI != CaseVals.end(); CI++) { + Expr *CaseExpr = CI->second->getLHS(); + if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd, + CI->first)) + Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum) + << CondTypeBeforePromotion; } + // See which of case ranges aren't in enum EI = EnumVals.begin(); for (CaseRangesTy::const_iterator RI = CaseRanges.begin(); - RI != CaseRanges.end() && EI != EIend; RI++) { - while (EI != EIend && EI->first < RI->first) - EI++; - - if (EI == EIend || EI->first != RI->first) { - Expr *CaseExpr = RI->second->getLHS(); - if (ShouldDiagnoseSwitchCaseNotInEnum(Context, ED, CaseExpr)) - Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum) - << CondTypeBeforePromotion; - } + RI != CaseRanges.end(); RI++) { + Expr *CaseExpr = RI->second->getLHS(); + if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd, + RI->first)) + Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum) + << CondTypeBeforePromotion; llvm::APSInt Hi = RI->second->getRHS()->EvaluateKnownConstInt(Context); AdjustAPSInt(Hi, CondWidth, CondIsSigned); - while (EI != EIend && EI->first < Hi) - EI++; - if (EI == EIend || EI->first != Hi) { - Expr *CaseExpr = RI->second->getRHS(); - if (ShouldDiagnoseSwitchCaseNotInEnum(Context, ED, CaseExpr)) - Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum) - << CondTypeBeforePromotion; - } + + CaseExpr = RI->second->getRHS(); + if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd, + Hi)) + Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum) + << CondTypeBeforePromotion; } // Check which enum vals aren't in switch - CaseValsTy::const_iterator CI = CaseVals.begin(); - CaseRangesTy::const_iterator RI = CaseRanges.begin(); + auto CI = CaseVals.begin(); + auto RI = CaseRanges.begin(); bool hasCasesNotInSwitch = false; SmallVector<DeclarationName,8> UnhandledNames; - for (EI = EnumVals.begin(); EI != EIend; EI++){ + for (EI = EnumVals.begin(); EI != EIEnd; EI++){ // Drop unneeded case values while (CI != CaseVals.end() && CI->first < EI->first) CI++; @@ -1135,29 +1138,15 @@ Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch, Diag(TheDefaultStmt->getDefaultLoc(), diag::warn_unreachable_default); // Produce a nice diagnostic if multiple values aren't handled. - switch (UnhandledNames.size()) { - case 0: break; - case 1: - Diag(CondExpr->getExprLoc(), TheDefaultStmt - ? diag::warn_def_missing_case1 : diag::warn_missing_case1) - << UnhandledNames[0]; - break; - case 2: - Diag(CondExpr->getExprLoc(), TheDefaultStmt - ? diag::warn_def_missing_case2 : diag::warn_missing_case2) - << UnhandledNames[0] << UnhandledNames[1]; - break; - case 3: - Diag(CondExpr->getExprLoc(), TheDefaultStmt - ? diag::warn_def_missing_case3 : diag::warn_missing_case3) - << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2]; - break; - default: - Diag(CondExpr->getExprLoc(), TheDefaultStmt - ? diag::warn_def_missing_cases : diag::warn_missing_cases) - << (unsigned)UnhandledNames.size() - << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2]; - break; + if (!UnhandledNames.empty()) { + DiagnosticBuilder DB = Diag(CondExpr->getExprLoc(), + TheDefaultStmt ? diag::warn_def_missing_case + : diag::warn_missing_case) + << (int)UnhandledNames.size(); + + for (size_t I = 0, E = std::min(UnhandledNames.size(), (size_t)3); + I != E; ++I) + DB << UnhandledNames[I]; } if (!hasCasesNotInSwitch) @@ -1195,30 +1184,37 @@ Sema::DiagnoseAssignmentEnum(QualType DstType, QualType SrcType, llvm::APSInt RhsVal = SrcExpr->EvaluateKnownConstInt(Context); AdjustAPSInt(RhsVal, DstWidth, DstIsSigned); const EnumDecl *ED = ET->getDecl(); - typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl *>, 64> - EnumValsTy; - EnumValsTy EnumVals; - - // Gather all enum values, set their type and sort them, - // allowing easier comparison with rhs constant. - for (auto *EDI : ED->enumerators()) { - llvm::APSInt Val = EDI->getInitVal(); - AdjustAPSInt(Val, DstWidth, DstIsSigned); - EnumVals.push_back(std::make_pair(Val, EDI)); - } - if (EnumVals.empty()) - return; - std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals); - EnumValsTy::iterator EIend = - std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals); - - // See which values aren't in the enum. - EnumValsTy::const_iterator EI = EnumVals.begin(); - while (EI != EIend && EI->first < RhsVal) - EI++; - if (EI == EIend || EI->first != RhsVal) { - Diag(SrcExpr->getExprLoc(), diag::warn_not_in_enum_assignment) + + if (ED->hasAttr<FlagEnumAttr>()) { + if (!IsValueInFlagEnum(ED, RhsVal, true)) + Diag(SrcExpr->getExprLoc(), diag::warn_not_in_enum_assignment) << DstType.getUnqualifiedType(); + } else { + typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl *>, 64> + EnumValsTy; + EnumValsTy EnumVals; + + // Gather all enum values, set their type and sort them, + // allowing easier comparison with rhs constant. + for (auto *EDI : ED->enumerators()) { + llvm::APSInt Val = EDI->getInitVal(); + AdjustAPSInt(Val, DstWidth, DstIsSigned); + EnumVals.push_back(std::make_pair(Val, EDI)); + } + if (EnumVals.empty()) + return; + std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals); + EnumValsTy::iterator EIend = + std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals); + + // See which values aren't in the enum. + EnumValsTy::const_iterator EI = EnumVals.begin(); + while (EI != EIend && EI->first < RhsVal) + EI++; + if (EI == EIend || EI->first != RhsVal) { + Diag(SrcExpr->getExprLoc(), diag::warn_not_in_enum_assignment) + << DstType.getUnqualifiedType(); + } } } } @@ -1832,6 +1828,15 @@ Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc, /// \return true if an error occurs. static bool FinishForRangeVarDecl(Sema &SemaRef, VarDecl *Decl, Expr *Init, SourceLocation Loc, int DiagID) { + if (Decl->getType()->isUndeducedType()) { + ExprResult Res = SemaRef.CorrectDelayedTyposInExpr(Init); + if (!Res.isUsable()) { + Decl->setInvalidDecl(); + return true; + } + Init = Res.get(); + } + // Deduce the type for the iterator variable now rather than leaving it to // AddInitializerToDecl, so we can produce a more suitable diagnostic. QualType InitType; @@ -2368,6 +2373,156 @@ StmtResult Sema::FinishObjCForCollectionStmt(Stmt *S, Stmt *B) { return S; } +// Warn when the loop variable is a const reference that creates a copy. +// Suggest using the non-reference type for copies. If a copy can be prevented +// suggest the const reference type that would do so. +// For instance, given "for (const &Foo : Range)", suggest +// "for (const Foo : Range)" to denote a copy is made for the loop. If +// possible, also suggest "for (const &Bar : Range)" if this type prevents +// the copy altogether. +static void DiagnoseForRangeReferenceVariableCopies(Sema &SemaRef, + const VarDecl *VD, + QualType RangeInitType) { + const Expr *InitExpr = VD->getInit(); + if (!InitExpr) + return; + + QualType VariableType = VD->getType(); + + const MaterializeTemporaryExpr *MTE = + dyn_cast<MaterializeTemporaryExpr>(InitExpr); + + // No copy made. + if (!MTE) + return; + + const Expr *E = MTE->GetTemporaryExpr()->IgnoreImpCasts(); + + // Searching for either UnaryOperator for dereference of a pointer or + // CXXOperatorCallExpr for handling iterators. + while (!isa<CXXOperatorCallExpr>(E) && !isa<UnaryOperator>(E)) { + if (const CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(E)) { + E = CCE->getArg(0); + } else if (const CXXMemberCallExpr *Call = dyn_cast<CXXMemberCallExpr>(E)) { + const MemberExpr *ME = cast<MemberExpr>(Call->getCallee()); + E = ME->getBase(); + } else { + const MaterializeTemporaryExpr *MTE = cast<MaterializeTemporaryExpr>(E); + E = MTE->GetTemporaryExpr(); + } + E = E->IgnoreImpCasts(); + } + + bool ReturnsReference = false; + if (isa<UnaryOperator>(E)) { + ReturnsReference = true; + } else { + const CXXOperatorCallExpr *Call = cast<CXXOperatorCallExpr>(E); + const FunctionDecl *FD = Call->getDirectCallee(); + QualType ReturnType = FD->getReturnType(); + ReturnsReference = ReturnType->isReferenceType(); + } + + if (ReturnsReference) { + // Loop variable creates a temporary. Suggest either to go with + // non-reference loop variable to indiciate a copy is made, or + // the correct time to bind a const reference. + SemaRef.Diag(VD->getLocation(), diag::warn_for_range_const_reference_copy) + << VD << VariableType << E->getType(); + QualType NonReferenceType = VariableType.getNonReferenceType(); + NonReferenceType.removeLocalConst(); + QualType NewReferenceType = + SemaRef.Context.getLValueReferenceType(E->getType().withConst()); + SemaRef.Diag(VD->getLocStart(), diag::note_use_type_or_non_reference) + << NonReferenceType << NewReferenceType << VD->getSourceRange(); + } else { + // The range always returns a copy, so a temporary is always created. + // Suggest removing the reference from the loop variable. + SemaRef.Diag(VD->getLocation(), diag::warn_for_range_variable_always_copy) + << VD << RangeInitType; + QualType NonReferenceType = VariableType.getNonReferenceType(); + NonReferenceType.removeLocalConst(); + SemaRef.Diag(VD->getLocStart(), diag::note_use_non_reference_type) + << NonReferenceType << VD->getSourceRange(); + } +} + +// Warns when the loop variable can be changed to a reference type to +// prevent a copy. For instance, if given "for (const Foo x : Range)" suggest +// "for (const Foo &x : Range)" if this form does not make a copy. +static void DiagnoseForRangeConstVariableCopies(Sema &SemaRef, + const VarDecl *VD) { + const Expr *InitExpr = VD->getInit(); + if (!InitExpr) + return; + + QualType VariableType = VD->getType(); + + if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(InitExpr)) { + if (!CE->getConstructor()->isCopyConstructor()) + return; + } else if (const CastExpr *CE = dyn_cast<CastExpr>(InitExpr)) { + if (CE->getCastKind() != CK_LValueToRValue) + return; + } else { + return; + } + + // TODO: Determine a maximum size that a POD type can be before a diagnostic + // should be emitted. Also, only ignore POD types with trivial copy + // constructors. + if (VariableType.isPODType(SemaRef.Context)) + return; + + // Suggest changing from a const variable to a const reference variable + // if doing so will prevent a copy. + SemaRef.Diag(VD->getLocation(), diag::warn_for_range_copy) + << VD << VariableType << InitExpr->getType(); + SemaRef.Diag(VD->getLocStart(), diag::note_use_reference_type) + << SemaRef.Context.getLValueReferenceType(VariableType) + << VD->getSourceRange(); +} + +/// DiagnoseForRangeVariableCopies - Diagnose three cases and fixes for them. +/// 1) for (const foo &x : foos) where foos only returns a copy. Suggest +/// using "const foo x" to show that a copy is made +/// 2) for (const bar &x : foos) where bar is a temporary intialized by bar. +/// Suggest either "const bar x" to keep the copying or "const foo& x" to +/// prevent the copy. +/// 3) for (const foo x : foos) where x is constructed from a reference foo. +/// Suggest "const foo &x" to prevent the copy. +static void DiagnoseForRangeVariableCopies(Sema &SemaRef, + const CXXForRangeStmt *ForStmt) { + if (SemaRef.Diags.isIgnored(diag::warn_for_range_const_reference_copy, + ForStmt->getLocStart()) && + SemaRef.Diags.isIgnored(diag::warn_for_range_variable_always_copy, + ForStmt->getLocStart()) && + SemaRef.Diags.isIgnored(diag::warn_for_range_copy, + ForStmt->getLocStart())) { + return; + } + + const VarDecl *VD = ForStmt->getLoopVariable(); + if (!VD) + return; + + QualType VariableType = VD->getType(); + + if (VariableType->isIncompleteType()) + return; + + const Expr *InitExpr = VD->getInit(); + if (!InitExpr) + return; + + if (VariableType->isReferenceType()) { + DiagnoseForRangeReferenceVariableCopies(SemaRef, VD, + ForStmt->getRangeInit()->getType()); + } else if (VariableType.isConstQualified()) { + DiagnoseForRangeConstVariableCopies(SemaRef, VD); + } +} + /// FinishCXXForRangeStmt - Attach the body to a C++0x for-range statement. /// This is a separate step from ActOnCXXForRangeStmt because analysis of the /// body cannot be performed until after the type of the range variable is @@ -2385,6 +2540,8 @@ StmtResult Sema::FinishCXXForRangeStmt(Stmt *S, Stmt *B) { DiagnoseEmptyStmtBody(ForStmt->getRParenLoc(), B, diag::warn_empty_range_based_for_body); + DiagnoseForRangeVariableCopies(*this, ForStmt); + return S; } @@ -2423,6 +2580,14 @@ Sema::ActOnIndirectGotoStmt(SourceLocation GotoLoc, SourceLocation StarLoc, return new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E); } +static void CheckJumpOutOfSEHFinally(Sema &S, SourceLocation Loc, + const Scope &DestScope) { + if (!S.CurrentSEHFinally.empty() && + DestScope.Contains(*S.CurrentSEHFinally.back())) { + S.Diag(Loc, diag::warn_jump_out_of_seh_finally); + } +} + StmtResult Sema::ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope) { Scope *S = CurScope->getContinueParent(); @@ -2430,6 +2595,7 @@ Sema::ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope) { // C99 6.8.6.2p1: A break shall appear only in or as a loop body. return StmtError(Diag(ContinueLoc, diag::err_continue_not_in_loop)); } + CheckJumpOutOfSEHFinally(*this, ContinueLoc, *S); return new (Context) ContinueStmt(ContinueLoc); } @@ -2444,6 +2610,7 @@ Sema::ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope) { if (S->isOpenMPLoopScope()) return StmtError(Diag(BreakLoc, diag::err_omp_loop_cannot_use_stmt) << "break"); + CheckJumpOutOfSEHFinally(*this, BreakLoc, *S); return new (Context) BreakStmt(BreakLoc); } @@ -2903,6 +3070,8 @@ Sema::ActOnReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp, CurScope->setNoNRVO(); } + CheckJumpOutOfSEHFinally(*this, ReturnLoc, *CurScope->getFnParent()); + return R; } @@ -3179,7 +3348,7 @@ Sema::ActOnObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw, Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@throw"; if (!Throw) { - // @throw without an expression designates a rethrow (which much occur + // @throw without an expression designates a rethrow (which must occur // in the context of an @catch clause). Scope *AtCatchParent = CurScope; while (AtCatchParent && !AtCatchParent->isAtCatchScope()) @@ -3251,35 +3420,112 @@ Sema::ActOnObjCAutoreleasePoolStmt(SourceLocation AtLoc, Stmt *Body) { } namespace { +class CatchHandlerType { + QualType QT; + unsigned IsPointer : 1; -class TypeWithHandler { - QualType t; - CXXCatchStmt *stmt; -public: - TypeWithHandler(const QualType &type, CXXCatchStmt *statement) - : t(type), stmt(statement) {} + // This is a special constructor to be used only with DenseMapInfo's + // getEmptyKey() and getTombstoneKey() functions. + friend struct llvm::DenseMapInfo<CatchHandlerType>; + enum Unique { ForDenseMap }; + CatchHandlerType(QualType QT, Unique) : QT(QT), IsPointer(false) {} - // An arbitrary order is fine as long as it places identical - // types next to each other. - bool operator<(const TypeWithHandler &y) const { - if (t.getAsOpaquePtr() < y.t.getAsOpaquePtr()) - return true; - if (t.getAsOpaquePtr() > y.t.getAsOpaquePtr()) +public: + /// Used when creating a CatchHandlerType from a handler type; will determine + /// whether the type is a pointer or reference and will strip off the the top + /// level pointer and cv-qualifiers. + CatchHandlerType(QualType Q) : QT(Q), IsPointer(false) { + if (QT->isPointerType()) + IsPointer = true; + + if (IsPointer || QT->isReferenceType()) + QT = QT->getPointeeType(); + QT = QT.getUnqualifiedType(); + } + + /// Used when creating a CatchHandlerType from a base class type; pretends the + /// type passed in had the pointer qualifier, does not need to get an + /// unqualified type. + CatchHandlerType(QualType QT, bool IsPointer) + : QT(QT), IsPointer(IsPointer) {} + + QualType underlying() const { return QT; } + bool isPointer() const { return IsPointer; } + + friend bool operator==(const CatchHandlerType &LHS, + const CatchHandlerType &RHS) { + // If the pointer qualification does not match, we can return early. + if (LHS.IsPointer != RHS.IsPointer) return false; - else - return getTypeSpecStartLoc() < y.getTypeSpecStartLoc(); + // Otherwise, check the underlying type without cv-qualifiers. + return LHS.QT == RHS.QT; + } +}; +} // namespace + +namespace llvm { +template <> struct DenseMapInfo<CatchHandlerType> { + static CatchHandlerType getEmptyKey() { + return CatchHandlerType(DenseMapInfo<QualType>::getEmptyKey(), + CatchHandlerType::ForDenseMap); } - bool operator==(const TypeWithHandler& other) const { - return t == other.t; + static CatchHandlerType getTombstoneKey() { + return CatchHandlerType(DenseMapInfo<QualType>::getTombstoneKey(), + CatchHandlerType::ForDenseMap); } - CXXCatchStmt *getCatchStmt() const { return stmt; } - SourceLocation getTypeSpecStartLoc() const { - return stmt->getExceptionDecl()->getTypeSpecStartLoc(); + static unsigned getHashValue(const CatchHandlerType &Base) { + return DenseMapInfo<QualType>::getHashValue(Base.underlying()); } + + static bool isEqual(const CatchHandlerType &LHS, + const CatchHandlerType &RHS) { + return LHS == RHS; + } +}; + +// It's OK to treat CatchHandlerType as a POD type. +template <> struct isPodLike<CatchHandlerType> { + static const bool value = true; }; +} + +namespace { +class CatchTypePublicBases { + ASTContext &Ctx; + const llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> &TypesToCheck; + const bool CheckAgainstPointer; + + CXXCatchStmt *FoundHandler; + CanQualType FoundHandlerType; +public: + CatchTypePublicBases( + ASTContext &Ctx, + const llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> &T, bool C) + : Ctx(Ctx), TypesToCheck(T), CheckAgainstPointer(C), + FoundHandler(nullptr) {} + + CXXCatchStmt *getFoundHandler() const { return FoundHandler; } + CanQualType getFoundHandlerType() const { return FoundHandlerType; } + + static bool FindPublicBasesOfType(const CXXBaseSpecifier *S, CXXBasePath &, + void *User) { + auto &PBOT = *reinterpret_cast<CatchTypePublicBases *>(User); + if (S->getAccessSpecifier() == AccessSpecifier::AS_public) { + CatchHandlerType Check(S->getType(), PBOT.CheckAgainstPointer); + auto M = PBOT.TypesToCheck; + auto I = M.find(Check); + if (I != M.end()) { + PBOT.FoundHandler = I->second; + PBOT.FoundHandlerType = PBOT.Ctx.getCanonicalType(S->getType()); + return true; + } + } + return false; + } +}; } /// ActOnCXXTryBlock - Takes a try compound-statement and a number of @@ -3289,74 +3535,120 @@ StmtResult Sema::ActOnCXXTryBlock(SourceLocation TryLoc, Stmt *TryBlock, // Don't report an error if 'try' is used in system headers. if (!getLangOpts().CXXExceptions && !getSourceManager().isInSystemHeader(TryLoc)) - Diag(TryLoc, diag::err_exceptions_disabled) << "try"; + Diag(TryLoc, diag::err_exceptions_disabled) << "try"; if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope()) Diag(TryLoc, diag::err_omp_simd_region_cannot_use_stmt) << "try"; + sema::FunctionScopeInfo *FSI = getCurFunction(); + + // C++ try is incompatible with SEH __try. + if (!getLangOpts().Borland && FSI->FirstSEHTryLoc.isValid()) { + Diag(TryLoc, diag::err_mixing_cxx_try_seh_try); + Diag(FSI->FirstSEHTryLoc, diag::note_conflicting_try_here) << "'__try'"; + } + const unsigned NumHandlers = Handlers.size(); - assert(NumHandlers > 0 && + assert(!Handlers.empty() && "The parser shouldn't call this if there are no handlers."); - SmallVector<TypeWithHandler, 8> TypesWithHandlers; - + llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> HandledTypes; for (unsigned i = 0; i < NumHandlers; ++i) { - CXXCatchStmt *Handler = cast<CXXCatchStmt>(Handlers[i]); - if (!Handler->getExceptionDecl()) { - if (i < NumHandlers - 1) - return StmtError(Diag(Handler->getLocStart(), - diag::err_early_catch_all)); + CXXCatchStmt *H = cast<CXXCatchStmt>(Handlers[i]); + // Diagnose when the handler is a catch-all handler, but it isn't the last + // handler for the try block. [except.handle]p5. Also, skip exception + // declarations that are invalid, since we can't usefully report on them. + if (!H->getExceptionDecl()) { + if (i < NumHandlers - 1) + return StmtError(Diag(H->getLocStart(), diag::err_early_catch_all)); + continue; + } else if (H->getExceptionDecl()->isInvalidDecl()) continue; - } - - const QualType CaughtType = Handler->getCaughtType(); - const QualType CanonicalCaughtType = Context.getCanonicalType(CaughtType); - TypesWithHandlers.push_back(TypeWithHandler(CanonicalCaughtType, Handler)); - } - - // Detect handlers for the same type as an earlier one. - if (NumHandlers > 1) { - llvm::array_pod_sort(TypesWithHandlers.begin(), TypesWithHandlers.end()); - - TypeWithHandler prev = TypesWithHandlers[0]; - for (unsigned i = 1; i < TypesWithHandlers.size(); ++i) { - TypeWithHandler curr = TypesWithHandlers[i]; - if (curr == prev) { - Diag(curr.getTypeSpecStartLoc(), - diag::warn_exception_caught_by_earlier_handler) - << curr.getCatchStmt()->getCaughtType().getAsString(); - Diag(prev.getTypeSpecStartLoc(), - diag::note_previous_exception_handler) - << prev.getCatchStmt()->getCaughtType().getAsString(); + // Walk the type hierarchy to diagnose when this type has already been + // handled (duplication), or cannot be handled (derivation inversion). We + // ignore top-level cv-qualifiers, per [except.handle]p3 + CatchHandlerType HandlerCHT = + (QualType)Context.getCanonicalType(H->getCaughtType()); + + // We can ignore whether the type is a reference or a pointer; we need the + // underlying declaration type in order to get at the underlying record + // decl, if there is one. + QualType Underlying = HandlerCHT.underlying(); + if (auto *RD = Underlying->getAsCXXRecordDecl()) { + if (!RD->hasDefinition()) + continue; + // Check that none of the public, unambiguous base classes are in the + // map ([except.handle]p1). Give the base classes the same pointer + // qualification as the original type we are basing off of. This allows + // comparison against the handler type using the same top-level pointer + // as the original type. + CXXBasePaths Paths; + Paths.setOrigin(RD); + CatchTypePublicBases CTPB(Context, HandledTypes, HandlerCHT.isPointer()); + if (RD->lookupInBases(CatchTypePublicBases::FindPublicBasesOfType, &CTPB, + Paths)) { + const CXXCatchStmt *Problem = CTPB.getFoundHandler(); + if (!Paths.isAmbiguous(CTPB.getFoundHandlerType())) { + Diag(H->getExceptionDecl()->getTypeSpecStartLoc(), + diag::warn_exception_caught_by_earlier_handler) + << H->getCaughtType(); + Diag(Problem->getExceptionDecl()->getTypeSpecStartLoc(), + diag::note_previous_exception_handler) + << Problem->getCaughtType(); + } } + } - prev = curr; + // Add the type the list of ones we have handled; diagnose if we've already + // handled it. + auto R = HandledTypes.insert(std::make_pair(H->getCaughtType(), H)); + if (!R.second) { + const CXXCatchStmt *Problem = R.first->second; + Diag(H->getExceptionDecl()->getTypeSpecStartLoc(), + diag::warn_exception_caught_by_earlier_handler) + << H->getCaughtType(); + Diag(Problem->getExceptionDecl()->getTypeSpecStartLoc(), + diag::note_previous_exception_handler) + << Problem->getCaughtType(); } } - getCurFunction()->setHasBranchProtectedScope(); - - // FIXME: We should detect handlers that cannot catch anything because an - // earlier handler catches a superclass. Need to find a method that is not - // quadratic for this. - // Neither of these are explicitly forbidden, but every compiler detects them - // and warns. + FSI->setHasCXXTry(TryLoc); return CXXTryStmt::Create(Context, TryLoc, TryBlock, Handlers); } -StmtResult -Sema::ActOnSEHTryBlock(bool IsCXXTry, - SourceLocation TryLoc, - Stmt *TryBlock, - Stmt *Handler) { +StmtResult Sema::ActOnSEHTryBlock(bool IsCXXTry, SourceLocation TryLoc, + Stmt *TryBlock, Stmt *Handler) { assert(TryBlock && Handler); - getCurFunction()->setHasBranchProtectedScope(); + sema::FunctionScopeInfo *FSI = getCurFunction(); + + // SEH __try is incompatible with C++ try. Borland appears to support this, + // however. + if (!getLangOpts().Borland) { + if (FSI->FirstCXXTryLoc.isValid()) { + Diag(TryLoc, diag::err_mixing_cxx_try_seh_try); + Diag(FSI->FirstCXXTryLoc, diag::note_conflicting_try_here) << "'try'"; + } + } + + FSI->setHasSEHTry(TryLoc); - return SEHTryStmt::Create(Context,IsCXXTry,TryLoc,TryBlock,Handler); + // Reject __try in Obj-C methods, blocks, and captured decls, since we don't + // track if they use SEH. + DeclContext *DC = CurContext; + while (DC && !DC->isFunctionOrMethod()) + DC = DC->getParent(); + FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(DC); + if (FD) + FD->setUsesSEHTry(true); + else + Diag(TryLoc, diag::err_seh_try_outside_functions); + + return SEHTryStmt::Create(Context, IsCXXTry, TryLoc, TryBlock, Handler); } StmtResult @@ -3374,11 +3666,18 @@ Sema::ActOnSEHExceptBlock(SourceLocation Loc, return SEHExceptStmt::Create(Context,Loc,FilterExpr,Block); } -StmtResult -Sema::ActOnSEHFinallyBlock(SourceLocation Loc, - Stmt *Block) { +void Sema::ActOnStartSEHFinallyBlock() { + CurrentSEHFinally.push_back(CurScope); +} + +void Sema::ActOnAbortSEHFinallyBlock() { + CurrentSEHFinally.pop_back(); +} + +StmtResult Sema::ActOnFinishSEHFinallyBlock(SourceLocation Loc, Stmt *Block) { assert(Block); - return SEHFinallyStmt::Create(Context,Loc,Block); + CurrentSEHFinally.pop_back(); + return SEHFinallyStmt::Create(Context, Loc, Block); } StmtResult @@ -3388,6 +3687,7 @@ Sema::ActOnSEHLeaveStmt(SourceLocation Loc, Scope *CurScope) { SEHTryParent = SEHTryParent->getParent(); if (!SEHTryParent) return StmtError(Diag(Loc, diag::err_ms___leave_not_in___try)); + CheckJumpOutOfSEHFinally(*this, Loc, *SEHTryParent); return new (Context) SEHLeaveStmt(Loc); } |