//===--- Sema.cpp - AST Builder and Semantic Analysis Implementation ------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements the actions class which performs semantic analysis and // builds an AST out of a parse stream. // //===----------------------------------------------------------------------===// #include "clang/Sema/SemaInternal.h" #include "clang/AST/ASTContext.h" #include "clang/AST/ASTDiagnostic.h" #include "clang/AST/DeclCXX.h" #include "clang/AST/DeclFriend.h" #include "clang/AST/DeclObjC.h" #include "clang/AST/Expr.h" #include "clang/AST/ExprCXX.h" #include "clang/AST/StmtCXX.h" #include "clang/Basic/DiagnosticOptions.h" #include "clang/Basic/FileManager.h" #include "clang/Basic/PartialDiagnostic.h" #include "clang/Basic/TargetInfo.h" #include "clang/Lex/HeaderSearch.h" #include "clang/Lex/Preprocessor.h" #include "clang/Sema/CXXFieldCollector.h" #include "clang/Sema/DelayedDiagnostic.h" #include "clang/Sema/ExternalSemaSource.h" #include "clang/Sema/MultiplexExternalSemaSource.h" #include "clang/Sema/ObjCMethodList.h" #include "clang/Sema/PrettyDeclStackTrace.h" #include "clang/Sema/Scope.h" #include "clang/Sema/ScopeInfo.h" #include "clang/Sema/SemaConsumer.h" #include "clang/Sema/TemplateDeduction.h" #include "llvm/ADT/APFloat.h" #include "llvm/ADT/DenseMap.h" #include "llvm/ADT/SmallSet.h" using namespace clang; using namespace sema; SourceLocation Sema::getLocForEndOfToken(SourceLocation Loc, unsigned Offset) { return Lexer::getLocForEndOfToken(Loc, Offset, SourceMgr, LangOpts); } ModuleLoader &Sema::getModuleLoader() const { return PP.getModuleLoader(); } PrintingPolicy Sema::getPrintingPolicy(const ASTContext &Context, const Preprocessor &PP) { PrintingPolicy Policy = Context.getPrintingPolicy(); Policy.Bool = Context.getLangOpts().Bool; if (!Policy.Bool) { if (const MacroInfo * BoolMacro = PP.getMacroInfo(&Context.Idents.get("bool"))) { Policy.Bool = BoolMacro->isObjectLike() && BoolMacro->getNumTokens() == 1 && BoolMacro->getReplacementToken(0).is(tok::kw__Bool); } } return Policy; } void Sema::ActOnTranslationUnitScope(Scope *S) { TUScope = S; PushDeclContext(S, Context.getTranslationUnitDecl()); } Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer, TranslationUnitKind TUKind, CodeCompleteConsumer *CodeCompleter) : ExternalSource(nullptr), isMultiplexExternalSource(false), FPFeatures(pp.getLangOpts()), LangOpts(pp.getLangOpts()), PP(pp), Context(ctxt), Consumer(consumer), Diags(PP.getDiagnostics()), SourceMgr(PP.getSourceManager()), CollectStats(false), CodeCompleter(CodeCompleter), CurContext(nullptr), OriginalLexicalContext(nullptr), PackContext(nullptr), MSStructPragmaOn(false), MSPointerToMemberRepresentationMethod( LangOpts.getMSPointerToMemberRepresentationMethod()), VtorDispModeStack(1, MSVtorDispAttr::Mode(LangOpts.VtorDispMode)), DataSegStack(nullptr), BSSSegStack(nullptr), ConstSegStack(nullptr), CodeSegStack(nullptr), CurInitSeg(nullptr), VisContext(nullptr), IsBuildingRecoveryCallExpr(false), ExprNeedsCleanups(false), LateTemplateParser(nullptr), LateTemplateParserCleanup(nullptr), OpaqueParser(nullptr), IdResolver(pp), StdInitializerList(nullptr), CXXTypeInfoDecl(nullptr), MSVCGuidDecl(nullptr), NSNumberDecl(nullptr), NSValueDecl(nullptr), NSStringDecl(nullptr), StringWithUTF8StringMethod(nullptr), ValueWithBytesObjCTypeMethod(nullptr), NSArrayDecl(nullptr), ArrayWithObjectsMethod(nullptr), NSDictionaryDecl(nullptr), DictionaryWithObjectsMethod(nullptr), MSAsmLabelNameCounter(0), GlobalNewDeleteDeclared(false), TUKind(TUKind), NumSFINAEErrors(0), CachedFakeTopLevelModule(nullptr), AccessCheckingSFINAE(false), InNonInstantiationSFINAEContext(false), NonInstantiationEntries(0), ArgumentPackSubstitutionIndex(-1), CurrentInstantiationScope(nullptr), DisableTypoCorrection(false), TyposCorrected(0), AnalysisWarnings(*this), ThreadSafetyDeclCache(nullptr), VarDataSharingAttributesStack(nullptr), CurScope(nullptr), Ident_super(nullptr), Ident___float128(nullptr) { TUScope = nullptr; LoadedExternalKnownNamespaces = false; for (unsigned I = 0; I != NSAPI::NumNSNumberLiteralMethods; ++I) NSNumberLiteralMethods[I] = nullptr; if (getLangOpts().ObjC1) NSAPIObj.reset(new NSAPI(Context)); if (getLangOpts().CPlusPlus) FieldCollector.reset(new CXXFieldCollector()); // Tell diagnostics how to render things from the AST library. Diags.SetArgToStringFn(&FormatASTNodeDiagnosticArgument, &Context); ExprEvalContexts.emplace_back(PotentiallyEvaluated, 0, false, nullptr, false); FunctionScopes.push_back(new FunctionScopeInfo(Diags)); // Initilization of data sharing attributes stack for OpenMP InitDataSharingAttributesStack(); } void Sema::addImplicitTypedef(StringRef Name, QualType T) { DeclarationName DN = &Context.Idents.get(Name); if (IdResolver.begin(DN) == IdResolver.end()) PushOnScopeChains(Context.buildImplicitTypedef(T, Name), TUScope); } void Sema::Initialize() { if (SemaConsumer *SC = dyn_cast<SemaConsumer>(&Consumer)) SC->InitializeSema(*this); // Tell the external Sema source about this Sema object. if (ExternalSemaSource *ExternalSema = dyn_cast_or_null<ExternalSemaSource>(Context.getExternalSource())) ExternalSema->InitializeSema(*this); // This needs to happen after ExternalSemaSource::InitializeSema(this) or we // will not be able to merge any duplicate __va_list_tag decls correctly. VAListTagName = PP.getIdentifierInfo("__va_list_tag"); if (!TUScope) return; // Initialize predefined 128-bit integer types, if needed. if (Context.getTargetInfo().hasInt128Type()) { // If either of the 128-bit integer types are unavailable to name lookup, // define them now. DeclarationName Int128 = &Context.Idents.get("__int128_t"); if (IdResolver.begin(Int128) == IdResolver.end()) PushOnScopeChains(Context.getInt128Decl(), TUScope); DeclarationName UInt128 = &Context.Idents.get("__uint128_t"); if (IdResolver.begin(UInt128) == IdResolver.end()) PushOnScopeChains(Context.getUInt128Decl(), TUScope); } // Initialize predefined Objective-C types: if (getLangOpts().ObjC1) { // If 'SEL' does not yet refer to any declarations, make it refer to the // predefined 'SEL'. DeclarationName SEL = &Context.Idents.get("SEL"); if (IdResolver.begin(SEL) == IdResolver.end()) PushOnScopeChains(Context.getObjCSelDecl(), TUScope); // If 'id' does not yet refer to any declarations, make it refer to the // predefined 'id'. DeclarationName Id = &Context.Idents.get("id"); if (IdResolver.begin(Id) == IdResolver.end()) PushOnScopeChains(Context.getObjCIdDecl(), TUScope); // Create the built-in typedef for 'Class'. DeclarationName Class = &Context.Idents.get("Class"); if (IdResolver.begin(Class) == IdResolver.end()) PushOnScopeChains(Context.getObjCClassDecl(), TUScope); // Create the built-in forward declaratino for 'Protocol'. DeclarationName Protocol = &Context.Idents.get("Protocol"); if (IdResolver.begin(Protocol) == IdResolver.end()) PushOnScopeChains(Context.getObjCProtocolDecl(), TUScope); } // Initialize Microsoft "predefined C++ types". if (getLangOpts().MSVCCompat) { if (getLangOpts().CPlusPlus && IdResolver.begin(&Context.Idents.get("type_info")) == IdResolver.end()) PushOnScopeChains(Context.buildImplicitRecord("type_info", TTK_Class), TUScope); addImplicitTypedef("size_t", Context.getSizeType()); } // Initialize predefined OpenCL types. if (getLangOpts().OpenCL) { addImplicitTypedef("image1d_t", Context.OCLImage1dTy); addImplicitTypedef("image1d_array_t", Context.OCLImage1dArrayTy); addImplicitTypedef("image1d_buffer_t", Context.OCLImage1dBufferTy); addImplicitTypedef("image2d_t", Context.OCLImage2dTy); addImplicitTypedef("image2d_array_t", Context.OCLImage2dArrayTy); addImplicitTypedef("image3d_t", Context.OCLImage3dTy); addImplicitTypedef("sampler_t", Context.OCLSamplerTy); addImplicitTypedef("event_t", Context.OCLEventTy); if (getLangOpts().OpenCLVersion >= 200) { addImplicitTypedef("image2d_depth_t", Context.OCLImage2dDepthTy); addImplicitTypedef("image2d_array_depth_t", Context.OCLImage2dArrayDepthTy); addImplicitTypedef("image2d_msaa_t", Context.OCLImage2dMSAATy); addImplicitTypedef("image2d_array_msaa_t", Context.OCLImage2dArrayMSAATy); addImplicitTypedef("image2d_msaa_depth_t", Context.OCLImage2dMSAADepthTy); addImplicitTypedef("image2d_array_msaa_depth_t", Context.OCLImage2dArrayMSAADepthTy); addImplicitTypedef("clk_event_t", Context.OCLClkEventTy); addImplicitTypedef("queue_t", Context.OCLQueueTy); addImplicitTypedef("ndrange_t", Context.OCLNDRangeTy); addImplicitTypedef("reserve_id_t", Context.OCLReserveIDTy); addImplicitTypedef("atomic_int", Context.getAtomicType(Context.IntTy)); addImplicitTypedef("atomic_uint", Context.getAtomicType(Context.UnsignedIntTy)); addImplicitTypedef("atomic_long", Context.getAtomicType(Context.LongTy)); addImplicitTypedef("atomic_ulong", Context.getAtomicType(Context.UnsignedLongTy)); addImplicitTypedef("atomic_float", Context.getAtomicType(Context.FloatTy)); addImplicitTypedef("atomic_double", Context.getAtomicType(Context.DoubleTy)); // OpenCLC v2.0, s6.13.11.6 requires that atomic_flag is implemented as // 32-bit integer and OpenCLC v2.0, s6.1.1 int is always 32-bit wide. addImplicitTypedef("atomic_flag", Context.getAtomicType(Context.IntTy)); addImplicitTypedef("atomic_intptr_t", Context.getAtomicType(Context.getIntPtrType())); addImplicitTypedef("atomic_uintptr_t", Context.getAtomicType(Context.getUIntPtrType())); addImplicitTypedef("atomic_size_t", Context.getAtomicType(Context.getSizeType())); addImplicitTypedef("atomic_ptrdiff_t", Context.getAtomicType(Context.getPointerDiffType())); } } if (Context.getTargetInfo().hasBuiltinMSVaList()) { DeclarationName MSVaList = &Context.Idents.get("__builtin_ms_va_list"); if (IdResolver.begin(MSVaList) == IdResolver.end()) PushOnScopeChains(Context.getBuiltinMSVaListDecl(), TUScope); } DeclarationName BuiltinVaList = &Context.Idents.get("__builtin_va_list"); if (IdResolver.begin(BuiltinVaList) == IdResolver.end()) PushOnScopeChains(Context.getBuiltinVaListDecl(), TUScope); } Sema::~Sema() { llvm::DeleteContainerSeconds(LateParsedTemplateMap); if (PackContext) FreePackedContext(); if (VisContext) FreeVisContext(); // Kill all the active scopes. for (unsigned I = 1, E = FunctionScopes.size(); I != E; ++I) delete FunctionScopes[I]; if (FunctionScopes.size() == 1) delete FunctionScopes[0]; // Tell the SemaConsumer to forget about us; we're going out of scope. if (SemaConsumer *SC = dyn_cast<SemaConsumer>(&Consumer)) SC->ForgetSema(); // Detach from the external Sema source. if (ExternalSemaSource *ExternalSema = dyn_cast_or_null<ExternalSemaSource>(Context.getExternalSource())) ExternalSema->ForgetSema(); // If Sema's ExternalSource is the multiplexer - we own it. if (isMultiplexExternalSource) delete ExternalSource; threadSafety::threadSafetyCleanup(ThreadSafetyDeclCache); // Destroys data sharing attributes stack for OpenMP DestroyDataSharingAttributesStack(); assert(DelayedTypos.empty() && "Uncorrected typos!"); } /// makeUnavailableInSystemHeader - There is an error in the current /// context. If we're still in a system header, and we can plausibly /// make the relevant declaration unavailable instead of erroring, do /// so and return true. bool Sema::makeUnavailableInSystemHeader(SourceLocation loc, UnavailableAttr::ImplicitReason reason) { // If we're not in a function, it's an error. FunctionDecl *fn = dyn_cast<FunctionDecl>(CurContext); if (!fn) return false; // If we're in template instantiation, it's an error. if (!ActiveTemplateInstantiations.empty()) return false; // If that function's not in a system header, it's an error. if (!Context.getSourceManager().isInSystemHeader(loc)) return false; // If the function is already unavailable, it's not an error. if (fn->hasAttr<UnavailableAttr>()) return true; fn->addAttr(UnavailableAttr::CreateImplicit(Context, "", reason, loc)); return true; } ASTMutationListener *Sema::getASTMutationListener() const { return getASTConsumer().GetASTMutationListener(); } ///\brief Registers an external source. If an external source already exists, /// creates a multiplex external source and appends to it. /// ///\param[in] E - A non-null external sema source. /// void Sema::addExternalSource(ExternalSemaSource *E) { assert(E && "Cannot use with NULL ptr"); if (!ExternalSource) { ExternalSource = E; return; } if (isMultiplexExternalSource) static_cast<MultiplexExternalSemaSource*>(ExternalSource)->addSource(*E); else { ExternalSource = new MultiplexExternalSemaSource(*ExternalSource, *E); isMultiplexExternalSource = true; } } /// \brief Print out statistics about the semantic analysis. void Sema::PrintStats() const { llvm::errs() << "\n*** Semantic Analysis Stats:\n"; llvm::errs() << NumSFINAEErrors << " SFINAE diagnostics trapped.\n"; BumpAlloc.PrintStats(); AnalysisWarnings.PrintStats(); } void Sema::diagnoseNullableToNonnullConversion(QualType DstType, QualType SrcType, SourceLocation Loc) { Optional<NullabilityKind> ExprNullability = SrcType->getNullability(Context); if (!ExprNullability || *ExprNullability != NullabilityKind::Nullable) return; Optional<NullabilityKind> TypeNullability = DstType->getNullability(Context); if (!TypeNullability || *TypeNullability != NullabilityKind::NonNull) return; Diag(Loc, diag::warn_nullability_lost) << SrcType << DstType; } /// ImpCastExprToType - If Expr is not of type 'Type', insert an implicit cast. /// If there is already an implicit cast, merge into the existing one. /// The result is of the given category. ExprResult Sema::ImpCastExprToType(Expr *E, QualType Ty, CastKind Kind, ExprValueKind VK, const CXXCastPath *BasePath, CheckedConversionKind CCK) { #ifndef NDEBUG if (VK == VK_RValue && !E->isRValue()) { switch (Kind) { default: llvm_unreachable("can't implicitly cast lvalue to rvalue with this cast " "kind"); case CK_LValueToRValue: case CK_ArrayToPointerDecay: case CK_FunctionToPointerDecay: case CK_ToVoid: break; } } assert((VK == VK_RValue || !E->isRValue()) && "can't cast rvalue to lvalue"); #endif diagnoseNullableToNonnullConversion(Ty, E->getType(), E->getLocStart()); QualType ExprTy = Context.getCanonicalType(E->getType()); QualType TypeTy = Context.getCanonicalType(Ty); if (ExprTy == TypeTy) return E; if (ImplicitCastExpr *ImpCast = dyn_cast<ImplicitCastExpr>(E)) { if (ImpCast->getCastKind() == Kind && (!BasePath || BasePath->empty())) { ImpCast->setType(Ty); ImpCast->setValueKind(VK); return E; } } return ImplicitCastExpr::Create(Context, Ty, Kind, E, BasePath, VK); } /// ScalarTypeToBooleanCastKind - Returns the cast kind corresponding /// to the conversion from scalar type ScalarTy to the Boolean type. CastKind Sema::ScalarTypeToBooleanCastKind(QualType ScalarTy) { switch (ScalarTy->getScalarTypeKind()) { case Type::STK_Bool: return CK_NoOp; case Type::STK_CPointer: return CK_PointerToBoolean; case Type::STK_BlockPointer: return CK_PointerToBoolean; case Type::STK_ObjCObjectPointer: return CK_PointerToBoolean; case Type::STK_MemberPointer: return CK_MemberPointerToBoolean; case Type::STK_Integral: return CK_IntegralToBoolean; case Type::STK_Floating: return CK_FloatingToBoolean; case Type::STK_IntegralComplex: return CK_IntegralComplexToBoolean; case Type::STK_FloatingComplex: return CK_FloatingComplexToBoolean; } return CK_Invalid; } /// \brief Used to prune the decls of Sema's UnusedFileScopedDecls vector. static bool ShouldRemoveFromUnused(Sema *SemaRef, const DeclaratorDecl *D) { if (D->getMostRecentDecl()->isUsed()) return true; if (D->isExternallyVisible()) return true; if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { // UnusedFileScopedDecls stores the first declaration. // The declaration may have become definition so check again. const FunctionDecl *DeclToCheck; if (FD->hasBody(DeclToCheck)) return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck); // Later redecls may add new information resulting in not having to warn, // so check again. DeclToCheck = FD->getMostRecentDecl(); if (DeclToCheck != FD) return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck); } if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { // If a variable usable in constant expressions is referenced, // don't warn if it isn't used: if the value of a variable is required // for the computation of a constant expression, it doesn't make sense to // warn even if the variable isn't odr-used. (isReferenced doesn't // precisely reflect that, but it's a decent approximation.) if (VD->isReferenced() && VD->isUsableInConstantExpressions(SemaRef->Context)) return true; // UnusedFileScopedDecls stores the first declaration. // The declaration may have become definition so check again. const VarDecl *DeclToCheck = VD->getDefinition(); if (DeclToCheck) return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck); // Later redecls may add new information resulting in not having to warn, // so check again. DeclToCheck = VD->getMostRecentDecl(); if (DeclToCheck != VD) return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck); } return false; } /// Obtains a sorted list of functions that are undefined but ODR-used. void Sema::getUndefinedButUsed( SmallVectorImpl<std::pair<NamedDecl *, SourceLocation> > &Undefined) { for (llvm::DenseMap<NamedDecl *, SourceLocation>::iterator I = UndefinedButUsed.begin(), E = UndefinedButUsed.end(); I != E; ++I) { NamedDecl *ND = I->first; // Ignore attributes that have become invalid. if (ND->isInvalidDecl()) continue; // __attribute__((weakref)) is basically a definition. if (ND->hasAttr<WeakRefAttr>()) continue; if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) { if (FD->isDefined()) continue; if (FD->isExternallyVisible() && !FD->getMostRecentDecl()->isInlined()) continue; } else { if (cast<VarDecl>(ND)->hasDefinition() != VarDecl::DeclarationOnly) continue; if (ND->isExternallyVisible()) continue; } Undefined.push_back(std::make_pair(ND, I->second)); } // Sort (in order of use site) so that we're not dependent on the iteration // order through an llvm::DenseMap. SourceManager &SM = Context.getSourceManager(); std::sort(Undefined.begin(), Undefined.end(), [&SM](const std::pair<NamedDecl *, SourceLocation> &l, const std::pair<NamedDecl *, SourceLocation> &r) { if (l.second.isValid() && !r.second.isValid()) return true; if (!l.second.isValid() && r.second.isValid()) return false; if (l.second != r.second) return SM.isBeforeInTranslationUnit(l.second, r.second); return SM.isBeforeInTranslationUnit(l.first->getLocation(), r.first->getLocation()); }); } /// checkUndefinedButUsed - Check for undefined objects with internal linkage /// or that are inline. static void checkUndefinedButUsed(Sema &S) { if (S.UndefinedButUsed.empty()) return; // Collect all the still-undefined entities with internal linkage. SmallVector<std::pair<NamedDecl *, SourceLocation>, 16> Undefined; S.getUndefinedButUsed(Undefined); if (Undefined.empty()) return; for (SmallVectorImpl<std::pair<NamedDecl *, SourceLocation> >::iterator I = Undefined.begin(), E = Undefined.end(); I != E; ++I) { NamedDecl *ND = I->first; if (ND->hasAttr<DLLImportAttr>() || ND->hasAttr<DLLExportAttr>()) { // An exported function will always be emitted when defined, so even if // the function is inline, it doesn't have to be emitted in this TU. An // imported function implies that it has been exported somewhere else. continue; } if (!ND->isExternallyVisible()) { S.Diag(ND->getLocation(), diag::warn_undefined_internal) << isa<VarDecl>(ND) << ND; } else { assert(cast<FunctionDecl>(ND)->getMostRecentDecl()->isInlined() && "used object requires definition but isn't inline or internal?"); S.Diag(ND->getLocation(), diag::warn_undefined_inline) << ND; } if (I->second.isValid()) S.Diag(I->second, diag::note_used_here); } } void Sema::LoadExternalWeakUndeclaredIdentifiers() { if (!ExternalSource) return; SmallVector<std::pair<IdentifierInfo *, WeakInfo>, 4> WeakIDs; ExternalSource->ReadWeakUndeclaredIdentifiers(WeakIDs); for (auto &WeakID : WeakIDs) WeakUndeclaredIdentifiers.insert(WeakID); } typedef llvm::DenseMap<const CXXRecordDecl*, bool> RecordCompleteMap; /// \brief Returns true, if all methods and nested classes of the given /// CXXRecordDecl are defined in this translation unit. /// /// Should only be called from ActOnEndOfTranslationUnit so that all /// definitions are actually read. static bool MethodsAndNestedClassesComplete(const CXXRecordDecl *RD, RecordCompleteMap &MNCComplete) { RecordCompleteMap::iterator Cache = MNCComplete.find(RD); if (Cache != MNCComplete.end()) return Cache->second; if (!RD->isCompleteDefinition()) return false; bool Complete = true; for (DeclContext::decl_iterator I = RD->decls_begin(), E = RD->decls_end(); I != E && Complete; ++I) { if (const CXXMethodDecl *M = dyn_cast<CXXMethodDecl>(*I)) Complete = M->isDefined() || (M->isPure() && !isa<CXXDestructorDecl>(M)); else if (const FunctionTemplateDecl *F = dyn_cast<FunctionTemplateDecl>(*I)) // If the template function is marked as late template parsed at this // point, it has not been instantiated and therefore we have not // performed semantic analysis on it yet, so we cannot know if the type // can be considered complete. Complete = !F->getTemplatedDecl()->isLateTemplateParsed() && F->getTemplatedDecl()->isDefined(); else if (const CXXRecordDecl *R = dyn_cast<CXXRecordDecl>(*I)) { if (R->isInjectedClassName()) continue; if (R->hasDefinition()) Complete = MethodsAndNestedClassesComplete(R->getDefinition(), MNCComplete); else Complete = false; } } MNCComplete[RD] = Complete; return Complete; } /// \brief Returns true, if the given CXXRecordDecl is fully defined in this /// translation unit, i.e. all methods are defined or pure virtual and all /// friends, friend functions and nested classes are fully defined in this /// translation unit. /// /// Should only be called from ActOnEndOfTranslationUnit so that all /// definitions are actually read. static bool IsRecordFullyDefined(const CXXRecordDecl *RD, RecordCompleteMap &RecordsComplete, RecordCompleteMap &MNCComplete) { RecordCompleteMap::iterator Cache = RecordsComplete.find(RD); if (Cache != RecordsComplete.end()) return Cache->second; bool Complete = MethodsAndNestedClassesComplete(RD, MNCComplete); for (CXXRecordDecl::friend_iterator I = RD->friend_begin(), E = RD->friend_end(); I != E && Complete; ++I) { // Check if friend classes and methods are complete. if (TypeSourceInfo *TSI = (*I)->getFriendType()) { // Friend classes are available as the TypeSourceInfo of the FriendDecl. if (CXXRecordDecl *FriendD = TSI->getType()->getAsCXXRecordDecl()) Complete = MethodsAndNestedClassesComplete(FriendD, MNCComplete); else Complete = false; } else { // Friend functions are available through the NamedDecl of FriendDecl. if (const FunctionDecl *FD = dyn_cast<FunctionDecl>((*I)->getFriendDecl())) Complete = FD->isDefined(); else // This is a template friend, give up. Complete = false; } } RecordsComplete[RD] = Complete; return Complete; } void Sema::emitAndClearUnusedLocalTypedefWarnings() { if (ExternalSource) ExternalSource->ReadUnusedLocalTypedefNameCandidates( UnusedLocalTypedefNameCandidates); for (const TypedefNameDecl *TD : UnusedLocalTypedefNameCandidates) { if (TD->isReferenced()) continue; Diag(TD->getLocation(), diag::warn_unused_local_typedef) << isa<TypeAliasDecl>(TD) << TD->getDeclName(); } UnusedLocalTypedefNameCandidates.clear(); } /// ActOnEndOfTranslationUnit - This is called at the very end of the /// translation unit when EOF is reached and all but the top-level scope is /// popped. void Sema::ActOnEndOfTranslationUnit() { assert(DelayedDiagnostics.getCurrentPool() == nullptr && "reached end of translation unit with a pool attached?"); // If code completion is enabled, don't perform any end-of-translation-unit // work. if (PP.isCodeCompletionEnabled()) return; // Complete translation units and modules define vtables and perform implicit // instantiations. PCH files do not. if (TUKind != TU_Prefix) { DiagnoseUseOfUnimplementedSelectors(); // If DefinedUsedVTables ends up marking any virtual member functions it // might lead to more pending template instantiations, which we then need // to instantiate. DefineUsedVTables(); // C++: Perform implicit template instantiations. // // FIXME: When we perform these implicit instantiations, we do not // carefully keep track of the point of instantiation (C++ [temp.point]). // This means that name lookup that occurs within the template // instantiation will always happen at the end of the translation unit, // so it will find some names that are not required to be found. This is // valid, but we could do better by diagnosing if an instantiation uses a // name that was not visible at its first point of instantiation. if (ExternalSource) { // Load pending instantiations from the external source. SmallVector<PendingImplicitInstantiation, 4> Pending; ExternalSource->ReadPendingInstantiations(Pending); PendingInstantiations.insert(PendingInstantiations.begin(), Pending.begin(), Pending.end()); } PerformPendingInstantiations(); if (LateTemplateParserCleanup) LateTemplateParserCleanup(OpaqueParser); CheckDelayedMemberExceptionSpecs(); } // All delayed member exception specs should be checked or we end up accepting // incompatible declarations. // FIXME: This is wrong for TUKind == TU_Prefix. In that case, we need to // write out the lists to the AST file (if any). assert(DelayedDefaultedMemberExceptionSpecs.empty()); assert(DelayedExceptionSpecChecks.empty()); // All dllexport classes should have been processed already. assert(DelayedDllExportClasses.empty()); // Remove file scoped decls that turned out to be used. UnusedFileScopedDecls.erase( std::remove_if(UnusedFileScopedDecls.begin(nullptr, true), UnusedFileScopedDecls.end(), std::bind1st(std::ptr_fun(ShouldRemoveFromUnused), this)), UnusedFileScopedDecls.end()); if (TUKind == TU_Prefix) { // Translation unit prefixes don't need any of the checking below. TUScope = nullptr; return; } // Check for #pragma weak identifiers that were never declared LoadExternalWeakUndeclaredIdentifiers(); for (auto WeakID : WeakUndeclaredIdentifiers) { if (WeakID.second.getUsed()) continue; Decl *PrevDecl = LookupSingleName(TUScope, WeakID.first, SourceLocation(), LookupOrdinaryName); if (PrevDecl != nullptr && !(isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) Diag(WeakID.second.getLocation(), diag::warn_attribute_wrong_decl_type) << "'weak'" << ExpectedVariableOrFunction; else Diag(WeakID.second.getLocation(), diag::warn_weak_identifier_undeclared) << WeakID.first; } if (LangOpts.CPlusPlus11 && !Diags.isIgnored(diag::warn_delegating_ctor_cycle, SourceLocation())) CheckDelegatingCtorCycles(); if (TUKind == TU_Module) { // If we are building a module, resolve all of the exported declarations // now. if (Module *CurrentModule = PP.getCurrentModule()) { ModuleMap &ModMap = PP.getHeaderSearchInfo().getModuleMap(); SmallVector<Module *, 2> Stack; Stack.push_back(CurrentModule); while (!Stack.empty()) { Module *Mod = Stack.pop_back_val(); // Resolve the exported declarations and conflicts. // FIXME: Actually complain, once we figure out how to teach the // diagnostic client to deal with complaints in the module map at this // point. ModMap.resolveExports(Mod, /*Complain=*/false); ModMap.resolveUses(Mod, /*Complain=*/false); ModMap.resolveConflicts(Mod, /*Complain=*/false); // Queue the submodules, so their exports will also be resolved. Stack.append(Mod->submodule_begin(), Mod->submodule_end()); } } // Warnings emitted in ActOnEndOfTranslationUnit() should be emitted for // modules when they are built, not every time they are used. emitAndClearUnusedLocalTypedefWarnings(); // Modules don't need any of the checking below. TUScope = nullptr; return; } // C99 6.9.2p2: // A declaration of an identifier for an object that has file // scope without an initializer, and without a storage-class // specifier or with the storage-class specifier static, // constitutes a tentative definition. If a translation unit // contains one or more tentative definitions for an identifier, // and the translation unit contains no external definition for // that identifier, then the behavior is exactly as if the // translation unit contains a file scope declaration of that // identifier, with the composite type as of the end of the // translation unit, with an initializer equal to 0. llvm::SmallSet<VarDecl *, 32> Seen; for (TentativeDefinitionsType::iterator T = TentativeDefinitions.begin(ExternalSource), TEnd = TentativeDefinitions.end(); T != TEnd; ++T) { VarDecl *VD = (*T)->getActingDefinition(); // If the tentative definition was completed, getActingDefinition() returns // null. If we've already seen this variable before, insert()'s second // return value is false. if (!VD || VD->isInvalidDecl() || !Seen.insert(VD).second) continue; if (const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(VD->getType())) { // Set the length of the array to 1 (C99 6.9.2p5). Diag(VD->getLocation(), diag::warn_tentative_incomplete_array); llvm::APInt One(Context.getTypeSize(Context.getSizeType()), true); QualType T = Context.getConstantArrayType(ArrayT->getElementType(), One, ArrayType::Normal, 0); VD->setType(T); } else if (RequireCompleteType(VD->getLocation(), VD->getType(), diag::err_tentative_def_incomplete_type)) VD->setInvalidDecl(); CheckCompleteVariableDeclaration(VD); // Notify the consumer that we've completed a tentative definition. if (!VD->isInvalidDecl()) Consumer.CompleteTentativeDefinition(VD); } // If there were errors, disable 'unused' warnings since they will mostly be // noise. if (!Diags.hasErrorOccurred()) { // Output warning for unused file scoped decls. for (UnusedFileScopedDeclsType::iterator I = UnusedFileScopedDecls.begin(ExternalSource), E = UnusedFileScopedDecls.end(); I != E; ++I) { if (ShouldRemoveFromUnused(this, *I)) continue; if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) { const FunctionDecl *DiagD; if (!FD->hasBody(DiagD)) DiagD = FD; if (DiagD->isDeleted()) continue; // Deleted functions are supposed to be unused. if (DiagD->isReferenced()) { if (isa<CXXMethodDecl>(DiagD)) Diag(DiagD->getLocation(), diag::warn_unneeded_member_function) << DiagD->getDeclName(); else { if (FD->getStorageClass() == SC_Static && !FD->isInlineSpecified() && !SourceMgr.isInMainFile( SourceMgr.getExpansionLoc(FD->getLocation()))) Diag(DiagD->getLocation(), diag::warn_unneeded_static_internal_decl) << DiagD->getDeclName(); else Diag(DiagD->getLocation(), diag::warn_unneeded_internal_decl) << /*function*/0 << DiagD->getDeclName(); } } else { Diag(DiagD->getLocation(), isa<CXXMethodDecl>(DiagD) ? diag::warn_unused_member_function : diag::warn_unused_function) << DiagD->getDeclName(); } } else { const VarDecl *DiagD = cast<VarDecl>(*I)->getDefinition(); if (!DiagD) DiagD = cast<VarDecl>(*I); if (DiagD->isReferenced()) { Diag(DiagD->getLocation(), diag::warn_unneeded_internal_decl) << /*variable*/1 << DiagD->getDeclName(); } else if (DiagD->getType().isConstQualified()) { Diag(DiagD->getLocation(), diag::warn_unused_const_variable) << DiagD->getDeclName(); } else { Diag(DiagD->getLocation(), diag::warn_unused_variable) << DiagD->getDeclName(); } } } if (ExternalSource) ExternalSource->ReadUndefinedButUsed(UndefinedButUsed); checkUndefinedButUsed(*this); emitAndClearUnusedLocalTypedefWarnings(); } if (!Diags.isIgnored(diag::warn_unused_private_field, SourceLocation())) { RecordCompleteMap RecordsComplete; RecordCompleteMap MNCComplete; for (NamedDeclSetType::iterator I = UnusedPrivateFields.begin(), E = UnusedPrivateFields.end(); I != E; ++I) { const NamedDecl *D = *I; const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D->getDeclContext()); if (RD && !RD->isUnion() && IsRecordFullyDefined(RD, RecordsComplete, MNCComplete)) { Diag(D->getLocation(), diag::warn_unused_private_field) << D->getDeclName(); } } } if (!Diags.isIgnored(diag::warn_mismatched_delete_new, SourceLocation())) { if (ExternalSource) ExternalSource->ReadMismatchingDeleteExpressions(DeleteExprs); for (const auto &DeletedFieldInfo : DeleteExprs) { for (const auto &DeleteExprLoc : DeletedFieldInfo.second) { AnalyzeDeleteExprMismatch(DeletedFieldInfo.first, DeleteExprLoc.first, DeleteExprLoc.second); } } } // Check we've noticed that we're no longer parsing the initializer for every // variable. If we miss cases, then at best we have a performance issue and // at worst a rejects-valid bug. assert(ParsingInitForAutoVars.empty() && "Didn't unmark var as having its initializer parsed"); TUScope = nullptr; } //===----------------------------------------------------------------------===// // Helper functions. //===----------------------------------------------------------------------===// DeclContext *Sema::getFunctionLevelDeclContext() { DeclContext *DC = CurContext; while (true) { if (isa<BlockDecl>(DC) || isa<EnumDecl>(DC) || isa<CapturedDecl>(DC)) { DC = DC->getParent(); } else if (isa<CXXMethodDecl>(DC) && cast<CXXMethodDecl>(DC)->getOverloadedOperator() == OO_Call && cast<CXXRecordDecl>(DC->getParent())->isLambda()) { DC = DC->getParent()->getParent(); } else break; } return DC; } /// getCurFunctionDecl - If inside of a function body, this returns a pointer /// to the function decl for the function being parsed. If we're currently /// in a 'block', this returns the containing context. FunctionDecl *Sema::getCurFunctionDecl() { DeclContext *DC = getFunctionLevelDeclContext(); return dyn_cast<FunctionDecl>(DC); } ObjCMethodDecl *Sema::getCurMethodDecl() { DeclContext *DC = getFunctionLevelDeclContext(); while (isa<RecordDecl>(DC)) DC = DC->getParent(); return dyn_cast<ObjCMethodDecl>(DC); } NamedDecl *Sema::getCurFunctionOrMethodDecl() { DeclContext *DC = getFunctionLevelDeclContext(); if (isa<ObjCMethodDecl>(DC) || isa<FunctionDecl>(DC)) return cast<NamedDecl>(DC); return nullptr; } void Sema::EmitCurrentDiagnostic(unsigned DiagID) { // FIXME: It doesn't make sense to me that DiagID is an incoming argument here // and yet we also use the current diag ID on the DiagnosticsEngine. This has // been made more painfully obvious by the refactor that introduced this // function, but it is possible that the incoming argument can be // eliminnated. If it truly cannot be (for example, there is some reentrancy // issue I am not seeing yet), then there should at least be a clarifying // comment somewhere. if (Optional<TemplateDeductionInfo*> Info = isSFINAEContext()) { switch (DiagnosticIDs::getDiagnosticSFINAEResponse( Diags.getCurrentDiagID())) { case DiagnosticIDs::SFINAE_Report: // We'll report the diagnostic below. break; case DiagnosticIDs::SFINAE_SubstitutionFailure: // Count this failure so that we know that template argument deduction // has failed. ++NumSFINAEErrors; // Make a copy of this suppressed diagnostic and store it with the // template-deduction information. if (*Info && !(*Info)->hasSFINAEDiagnostic()) { Diagnostic DiagInfo(&Diags); (*Info)->addSFINAEDiagnostic(DiagInfo.getLocation(), PartialDiagnostic(DiagInfo, Context.getDiagAllocator())); } Diags.setLastDiagnosticIgnored(); Diags.Clear(); return; case DiagnosticIDs::SFINAE_AccessControl: { // Per C++ Core Issue 1170, access control is part of SFINAE. // Additionally, the AccessCheckingSFINAE flag can be used to temporarily // make access control a part of SFINAE for the purposes of checking // type traits. if (!AccessCheckingSFINAE && !getLangOpts().CPlusPlus11) break; SourceLocation Loc = Diags.getCurrentDiagLoc(); // Suppress this diagnostic. ++NumSFINAEErrors; // Make a copy of this suppressed diagnostic and store it with the // template-deduction information. if (*Info && !(*Info)->hasSFINAEDiagnostic()) { Diagnostic DiagInfo(&Diags); (*Info)->addSFINAEDiagnostic(DiagInfo.getLocation(), PartialDiagnostic(DiagInfo, Context.getDiagAllocator())); } Diags.setLastDiagnosticIgnored(); Diags.Clear(); // Now the diagnostic state is clear, produce a C++98 compatibility // warning. Diag(Loc, diag::warn_cxx98_compat_sfinae_access_control); // The last diagnostic which Sema produced was ignored. Suppress any // notes attached to it. Diags.setLastDiagnosticIgnored(); return; } case DiagnosticIDs::SFINAE_Suppress: // Make a copy of this suppressed diagnostic and store it with the // template-deduction information; if (*Info) { Diagnostic DiagInfo(&Diags); (*Info)->addSuppressedDiagnostic(DiagInfo.getLocation(), PartialDiagnostic(DiagInfo, Context.getDiagAllocator())); } // Suppress this diagnostic. Diags.setLastDiagnosticIgnored(); Diags.Clear(); return; } } // Set up the context's printing policy based on our current state. Context.setPrintingPolicy(getPrintingPolicy()); // Emit the diagnostic. if (!Diags.EmitCurrentDiagnostic()) return; // If this is not a note, and we're in a template instantiation // that is different from the last template instantiation where // we emitted an error, print a template instantiation // backtrace. if (!DiagnosticIDs::isBuiltinNote(DiagID) && !ActiveTemplateInstantiations.empty() && ActiveTemplateInstantiations.back() != LastTemplateInstantiationErrorContext) { PrintInstantiationStack(); LastTemplateInstantiationErrorContext = ActiveTemplateInstantiations.back(); } } Sema::SemaDiagnosticBuilder Sema::Diag(SourceLocation Loc, const PartialDiagnostic& PD) { SemaDiagnosticBuilder Builder(Diag(Loc, PD.getDiagID())); PD.Emit(Builder); return Builder; } /// \brief Looks through the macro-expansion chain for the given /// location, looking for a macro expansion with the given name. /// If one is found, returns true and sets the location to that /// expansion loc. bool Sema::findMacroSpelling(SourceLocation &locref, StringRef name) { SourceLocation loc = locref; if (!loc.isMacroID()) return false; // There's no good way right now to look at the intermediate // expansions, so just jump to the expansion location. loc = getSourceManager().getExpansionLoc(loc); // If that's written with the name, stop here. SmallVector<char, 16> buffer; if (getPreprocessor().getSpelling(loc, buffer) == name) { locref = loc; return true; } return false; } /// \brief Determines the active Scope associated with the given declaration /// context. /// /// This routine maps a declaration context to the active Scope object that /// represents that declaration context in the parser. It is typically used /// from "scope-less" code (e.g., template instantiation, lazy creation of /// declarations) that injects a name for name-lookup purposes and, therefore, /// must update the Scope. /// /// \returns The scope corresponding to the given declaraion context, or NULL /// if no such scope is open. Scope *Sema::getScopeForContext(DeclContext *Ctx) { if (!Ctx) return nullptr; Ctx = Ctx->getPrimaryContext(); for (Scope *S = getCurScope(); S; S = S->getParent()) { // Ignore scopes that cannot have declarations. This is important for // out-of-line definitions of static class members. if (S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) if (DeclContext *Entity = S->getEntity()) if (Ctx == Entity->getPrimaryContext()) return S; } return nullptr; } /// \brief Enter a new function scope void Sema::PushFunctionScope() { if (FunctionScopes.size() == 1) { // Use the "top" function scope rather than having to allocate // memory for a new scope. FunctionScopes.back()->Clear(); FunctionScopes.push_back(FunctionScopes.back()); return; } FunctionScopes.push_back(new FunctionScopeInfo(getDiagnostics())); } void Sema::PushBlockScope(Scope *BlockScope, BlockDecl *Block) { FunctionScopes.push_back(new BlockScopeInfo(getDiagnostics(), BlockScope, Block)); } LambdaScopeInfo *Sema::PushLambdaScope() { LambdaScopeInfo *const LSI = new LambdaScopeInfo(getDiagnostics()); FunctionScopes.push_back(LSI); return LSI; } void Sema::RecordParsingTemplateParameterDepth(unsigned Depth) { if (LambdaScopeInfo *const LSI = getCurLambda()) { LSI->AutoTemplateParameterDepth = Depth; return; } llvm_unreachable( "Remove assertion if intentionally called in a non-lambda context."); } void Sema::PopFunctionScopeInfo(const AnalysisBasedWarnings::Policy *WP, const Decl *D, const BlockExpr *blkExpr) { FunctionScopeInfo *Scope = FunctionScopes.pop_back_val(); assert(!FunctionScopes.empty() && "mismatched push/pop!"); // Issue any analysis-based warnings. if (WP && D) AnalysisWarnings.IssueWarnings(*WP, Scope, D, blkExpr); else for (const auto &PUD : Scope->PossiblyUnreachableDiags) Diag(PUD.Loc, PUD.PD); if (FunctionScopes.back() != Scope) delete Scope; } void Sema::PushCompoundScope() { getCurFunction()->CompoundScopes.push_back(CompoundScopeInfo()); } void Sema::PopCompoundScope() { FunctionScopeInfo *CurFunction = getCurFunction(); assert(!CurFunction->CompoundScopes.empty() && "mismatched push/pop"); CurFunction->CompoundScopes.pop_back(); } /// \brief Determine whether any errors occurred within this function/method/ /// block. bool Sema::hasAnyUnrecoverableErrorsInThisFunction() const { return getCurFunction()->ErrorTrap.hasUnrecoverableErrorOccurred(); } BlockScopeInfo *Sema::getCurBlock() { if (FunctionScopes.empty()) return nullptr; auto CurBSI = dyn_cast<BlockScopeInfo>(FunctionScopes.back()); if (CurBSI && CurBSI->TheDecl && !CurBSI->TheDecl->Encloses(CurContext)) { // We have switched contexts due to template instantiation. assert(!ActiveTemplateInstantiations.empty()); return nullptr; } return CurBSI; } LambdaScopeInfo *Sema::getCurLambda() { if (FunctionScopes.empty()) return nullptr; auto CurLSI = dyn_cast<LambdaScopeInfo>(FunctionScopes.back()); if (CurLSI && CurLSI->Lambda && !CurLSI->Lambda->Encloses(CurContext)) { // We have switched contexts due to template instantiation. assert(!ActiveTemplateInstantiations.empty()); return nullptr; } return CurLSI; } // We have a generic lambda if we parsed auto parameters, or we have // an associated template parameter list. LambdaScopeInfo *Sema::getCurGenericLambda() { if (LambdaScopeInfo *LSI = getCurLambda()) { return (LSI->AutoTemplateParams.size() || LSI->GLTemplateParameterList) ? LSI : nullptr; } return nullptr; } void Sema::ActOnComment(SourceRange Comment) { if (!LangOpts.RetainCommentsFromSystemHeaders && SourceMgr.isInSystemHeader(Comment.getBegin())) return; RawComment RC(SourceMgr, Comment, false, LangOpts.CommentOpts.ParseAllComments); if (RC.isAlmostTrailingComment()) { SourceRange MagicMarkerRange(Comment.getBegin(), Comment.getBegin().getLocWithOffset(3)); StringRef MagicMarkerText; switch (RC.getKind()) { case RawComment::RCK_OrdinaryBCPL: MagicMarkerText = "///<"; break; case RawComment::RCK_OrdinaryC: MagicMarkerText = "/**<"; break; default: llvm_unreachable("if this is an almost Doxygen comment, " "it should be ordinary"); } Diag(Comment.getBegin(), diag::warn_not_a_doxygen_trailing_member_comment) << FixItHint::CreateReplacement(MagicMarkerRange, MagicMarkerText); } Context.addComment(RC); } // Pin this vtable to this file. ExternalSemaSource::~ExternalSemaSource() {} void ExternalSemaSource::ReadMethodPool(Selector Sel) { } void ExternalSemaSource::ReadKnownNamespaces( SmallVectorImpl<NamespaceDecl *> &Namespaces) { } void ExternalSemaSource::ReadUndefinedButUsed( llvm::DenseMap<NamedDecl *, SourceLocation> &Undefined) { } void ExternalSemaSource::ReadMismatchingDeleteExpressions(llvm::MapVector< FieldDecl *, llvm::SmallVector<std::pair<SourceLocation, bool>, 4>> &) {} void PrettyDeclStackTraceEntry::print(raw_ostream &OS) const { SourceLocation Loc = this->Loc; if (!Loc.isValid() && TheDecl) Loc = TheDecl->getLocation(); if (Loc.isValid()) { Loc.print(OS, S.getSourceManager()); OS << ": "; } OS << Message; if (TheDecl && isa<NamedDecl>(TheDecl)) { std::string Name = cast<NamedDecl>(TheDecl)->getNameAsString(); if (!Name.empty()) OS << " '" << Name << '\''; } OS << '\n'; } /// \brief Figure out if an expression could be turned into a call. /// /// Use this when trying to recover from an error where the programmer may have /// written just the name of a function instead of actually calling it. /// /// \param E - The expression to examine. /// \param ZeroArgCallReturnTy - If the expression can be turned into a call /// with no arguments, this parameter is set to the type returned by such a /// call; otherwise, it is set to an empty QualType. /// \param OverloadSet - If the expression is an overloaded function /// name, this parameter is populated with the decls of the various overloads. bool Sema::tryExprAsCall(Expr &E, QualType &ZeroArgCallReturnTy, UnresolvedSetImpl &OverloadSet) { ZeroArgCallReturnTy = QualType(); OverloadSet.clear(); const OverloadExpr *Overloads = nullptr; bool IsMemExpr = false; if (E.getType() == Context.OverloadTy) { OverloadExpr::FindResult FR = OverloadExpr::find(const_cast<Expr*>(&E)); // Ignore overloads that are pointer-to-member constants. if (FR.HasFormOfMemberPointer) return false; Overloads = FR.Expression; } else if (E.getType() == Context.BoundMemberTy) { Overloads = dyn_cast<UnresolvedMemberExpr>(E.IgnoreParens()); IsMemExpr = true; } bool Ambiguous = false; if (Overloads) { for (OverloadExpr::decls_iterator it = Overloads->decls_begin(), DeclsEnd = Overloads->decls_end(); it != DeclsEnd; ++it) { OverloadSet.addDecl(*it); // Check whether the function is a non-template, non-member which takes no // arguments. if (IsMemExpr) continue; if (const FunctionDecl *OverloadDecl = dyn_cast<FunctionDecl>((*it)->getUnderlyingDecl())) { if (OverloadDecl->getMinRequiredArguments() == 0) { if (!ZeroArgCallReturnTy.isNull() && !Ambiguous) { ZeroArgCallReturnTy = QualType(); Ambiguous = true; } else ZeroArgCallReturnTy = OverloadDecl->getReturnType(); } } } // If it's not a member, use better machinery to try to resolve the call if (!IsMemExpr) return !ZeroArgCallReturnTy.isNull(); } // Attempt to call the member with no arguments - this will correctly handle // member templates with defaults/deduction of template arguments, overloads // with default arguments, etc. if (IsMemExpr && !E.isTypeDependent()) { bool Suppress = getDiagnostics().getSuppressAllDiagnostics(); getDiagnostics().setSuppressAllDiagnostics(true); ExprResult R = BuildCallToMemberFunction(nullptr, &E, SourceLocation(), None, SourceLocation()); getDiagnostics().setSuppressAllDiagnostics(Suppress); if (R.isUsable()) { ZeroArgCallReturnTy = R.get()->getType(); return true; } return false; } if (const DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(E.IgnoreParens())) { if (const FunctionDecl *Fun = dyn_cast<FunctionDecl>(DeclRef->getDecl())) { if (Fun->getMinRequiredArguments() == 0) ZeroArgCallReturnTy = Fun->getReturnType(); return true; } } // We don't have an expression that's convenient to get a FunctionDecl from, // but we can at least check if the type is "function of 0 arguments". QualType ExprTy = E.getType(); const FunctionType *FunTy = nullptr; QualType PointeeTy = ExprTy->getPointeeType(); if (!PointeeTy.isNull()) FunTy = PointeeTy->getAs<FunctionType>(); if (!FunTy) FunTy = ExprTy->getAs<FunctionType>(); if (const FunctionProtoType *FPT = dyn_cast_or_null<FunctionProtoType>(FunTy)) { if (FPT->getNumParams() == 0) ZeroArgCallReturnTy = FunTy->getReturnType(); return true; } return false; } /// \brief Give notes for a set of overloads. /// /// A companion to tryExprAsCall. In cases when the name that the programmer /// wrote was an overloaded function, we may be able to make some guesses about /// plausible overloads based on their return types; such guesses can be handed /// off to this method to be emitted as notes. /// /// \param Overloads - The overloads to note. /// \param FinalNoteLoc - If we've suppressed printing some overloads due to /// -fshow-overloads=best, this is the location to attach to the note about too /// many candidates. Typically this will be the location of the original /// ill-formed expression. static void noteOverloads(Sema &S, const UnresolvedSetImpl &Overloads, const SourceLocation FinalNoteLoc) { int ShownOverloads = 0; int SuppressedOverloads = 0; for (UnresolvedSetImpl::iterator It = Overloads.begin(), DeclsEnd = Overloads.end(); It != DeclsEnd; ++It) { // FIXME: Magic number for max shown overloads stolen from // OverloadCandidateSet::NoteCandidates. if (ShownOverloads >= 4 && S.Diags.getShowOverloads() == Ovl_Best) { ++SuppressedOverloads; continue; } NamedDecl *Fn = (*It)->getUnderlyingDecl(); S.Diag(Fn->getLocation(), diag::note_possible_target_of_call); ++ShownOverloads; } if (SuppressedOverloads) S.Diag(FinalNoteLoc, diag::note_ovl_too_many_candidates) << SuppressedOverloads; } static void notePlausibleOverloads(Sema &S, SourceLocation Loc, const UnresolvedSetImpl &Overloads, bool (*IsPlausibleResult)(QualType)) { if (!IsPlausibleResult) return noteOverloads(S, Overloads, Loc); UnresolvedSet<2> PlausibleOverloads; for (OverloadExpr::decls_iterator It = Overloads.begin(), DeclsEnd = Overloads.end(); It != DeclsEnd; ++It) { const FunctionDecl *OverloadDecl = cast<FunctionDecl>(*It); QualType OverloadResultTy = OverloadDecl->getReturnType(); if (IsPlausibleResult(OverloadResultTy)) PlausibleOverloads.addDecl(It.getDecl()); } noteOverloads(S, PlausibleOverloads, Loc); } /// Determine whether the given expression can be called by just /// putting parentheses after it. Notably, expressions with unary /// operators can't be because the unary operator will start parsing /// outside the call. static bool IsCallableWithAppend(Expr *E) { E = E->IgnoreImplicit(); return (!isa<CStyleCastExpr>(E) && !isa<UnaryOperator>(E) && !isa<BinaryOperator>(E) && !isa<CXXOperatorCallExpr>(E)); } bool Sema::tryToRecoverWithCall(ExprResult &E, const PartialDiagnostic &PD, bool ForceComplain, bool (*IsPlausibleResult)(QualType)) { SourceLocation Loc = E.get()->getExprLoc(); SourceRange Range = E.get()->getSourceRange(); QualType ZeroArgCallTy; UnresolvedSet<4> Overloads; if (tryExprAsCall(*E.get(), ZeroArgCallTy, Overloads) && !ZeroArgCallTy.isNull() && (!IsPlausibleResult || IsPlausibleResult(ZeroArgCallTy))) { // At this point, we know E is potentially callable with 0 // arguments and that it returns something of a reasonable type, // so we can emit a fixit and carry on pretending that E was // actually a CallExpr. SourceLocation ParenInsertionLoc = getLocForEndOfToken(Range.getEnd()); Diag(Loc, PD) << /*zero-arg*/ 1 << Range << (IsCallableWithAppend(E.get()) ? FixItHint::CreateInsertion(ParenInsertionLoc, "()") : FixItHint()); notePlausibleOverloads(*this, Loc, Overloads, IsPlausibleResult); // FIXME: Try this before emitting the fixit, and suppress diagnostics // while doing so. E = ActOnCallExpr(nullptr, E.get(), Range.getEnd(), None, Range.getEnd().getLocWithOffset(1)); return true; } if (!ForceComplain) return false; Diag(Loc, PD) << /*not zero-arg*/ 0 << Range; notePlausibleOverloads(*this, Loc, Overloads, IsPlausibleResult); E = ExprError(); return true; } IdentifierInfo *Sema::getSuperIdentifier() const { if (!Ident_super) Ident_super = &Context.Idents.get("super"); return Ident_super; } IdentifierInfo *Sema::getFloat128Identifier() const { if (!Ident___float128) Ident___float128 = &Context.Idents.get("__float128"); return Ident___float128; } void Sema::PushCapturedRegionScope(Scope *S, CapturedDecl *CD, RecordDecl *RD, CapturedRegionKind K) { CapturingScopeInfo *CSI = new CapturedRegionScopeInfo( getDiagnostics(), S, CD, RD, CD->getContextParam(), K); CSI->ReturnType = Context.VoidTy; FunctionScopes.push_back(CSI); } CapturedRegionScopeInfo *Sema::getCurCapturedRegion() { if (FunctionScopes.empty()) return nullptr; return dyn_cast<CapturedRegionScopeInfo>(FunctionScopes.back()); } const llvm::MapVector<FieldDecl *, Sema::DeleteLocs> & Sema::getMismatchingDeleteExpressions() const { return DeleteExprs; }