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Diffstat (limited to 'contrib/llvm/tools/clang/lib/Sema/SemaExpr.cpp')
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diff --git a/contrib/llvm/tools/clang/lib/Sema/SemaExpr.cpp b/contrib/llvm/tools/clang/lib/Sema/SemaExpr.cpp new file mode 100644 index 0000000..0d0f2f5 --- /dev/null +++ b/contrib/llvm/tools/clang/lib/Sema/SemaExpr.cpp @@ -0,0 +1,11289 @@ +//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements semantic analysis for expressions. +// +//===----------------------------------------------------------------------===// + +#include "clang/Sema/SemaInternal.h" +#include "clang/Sema/DelayedDiagnostic.h" +#include "clang/Sema/Initialization.h" +#include "clang/Sema/Lookup.h" +#include "clang/Sema/ScopeInfo.h" +#include "clang/Sema/AnalysisBasedWarnings.h" +#include "clang/AST/ASTContext.h" +#include "clang/AST/ASTConsumer.h" +#include "clang/AST/ASTMutationListener.h" +#include "clang/AST/CXXInheritance.h" +#include "clang/AST/DeclObjC.h" +#include "clang/AST/DeclTemplate.h" +#include "clang/AST/EvaluatedExprVisitor.h" +#include "clang/AST/Expr.h" +#include "clang/AST/ExprCXX.h" +#include "clang/AST/ExprObjC.h" +#include "clang/AST/RecursiveASTVisitor.h" +#include "clang/AST/TypeLoc.h" +#include "clang/Basic/PartialDiagnostic.h" +#include "clang/Basic/SourceManager.h" +#include "clang/Basic/TargetInfo.h" +#include "clang/Lex/LiteralSupport.h" +#include "clang/Lex/Preprocessor.h" +#include "clang/Sema/DeclSpec.h" +#include "clang/Sema/Designator.h" +#include "clang/Sema/Scope.h" +#include "clang/Sema/ScopeInfo.h" +#include "clang/Sema/ParsedTemplate.h" +#include "clang/Sema/SemaFixItUtils.h" +#include "clang/Sema/Template.h" +#include "TreeTransform.h" +using namespace clang; +using namespace sema; + +/// \brief Determine whether the use of this declaration is valid, without +/// emitting diagnostics. +bool Sema::CanUseDecl(NamedDecl *D) { + // See if this is an auto-typed variable whose initializer we are parsing. + if (ParsingInitForAutoVars.count(D)) + return false; + + // See if this is a deleted function. + if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { + if (FD->isDeleted()) + return false; + } + + // See if this function is unavailable. + if (D->getAvailability() == AR_Unavailable && + cast<Decl>(CurContext)->getAvailability() != AR_Unavailable) + return false; + + return true; +} + +static AvailabilityResult DiagnoseAvailabilityOfDecl(Sema &S, + NamedDecl *D, SourceLocation Loc, + const ObjCInterfaceDecl *UnknownObjCClass) { + // See if this declaration is unavailable or deprecated. + std::string Message; + AvailabilityResult Result = D->getAvailability(&Message); + if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(D)) + if (Result == AR_Available) { + const DeclContext *DC = ECD->getDeclContext(); + if (const EnumDecl *TheEnumDecl = dyn_cast<EnumDecl>(DC)) + Result = TheEnumDecl->getAvailability(&Message); + } + + switch (Result) { + case AR_Available: + case AR_NotYetIntroduced: + break; + + case AR_Deprecated: + S.EmitDeprecationWarning(D, Message, Loc, UnknownObjCClass); + break; + + case AR_Unavailable: + if (S.getCurContextAvailability() != AR_Unavailable) { + if (Message.empty()) { + if (!UnknownObjCClass) + S.Diag(Loc, diag::err_unavailable) << D->getDeclName(); + else + S.Diag(Loc, diag::warn_unavailable_fwdclass_message) + << D->getDeclName(); + } + else + S.Diag(Loc, diag::err_unavailable_message) + << D->getDeclName() << Message; + S.Diag(D->getLocation(), diag::note_unavailable_here) + << isa<FunctionDecl>(D) << false; + } + break; + } + return Result; +} + +/// \brief Emit a note explaining that this function is deleted or unavailable. +void Sema::NoteDeletedFunction(FunctionDecl *Decl) { + CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Decl); + + if (Method && Method->isDeleted() && !Method->isDeletedAsWritten()) { + // If the method was explicitly defaulted, point at that declaration. + if (!Method->isImplicit()) + Diag(Decl->getLocation(), diag::note_implicitly_deleted); + + // Try to diagnose why this special member function was implicitly + // deleted. This might fail, if that reason no longer applies. + CXXSpecialMember CSM = getSpecialMember(Method); + if (CSM != CXXInvalid) + ShouldDeleteSpecialMember(Method, CSM, /*Diagnose=*/true); + + return; + } + + Diag(Decl->getLocation(), diag::note_unavailable_here) + << 1 << Decl->isDeleted(); +} + +/// \brief Determine whether the use of this declaration is valid, and +/// emit any corresponding diagnostics. +/// +/// This routine diagnoses various problems with referencing +/// declarations that can occur when using a declaration. For example, +/// it might warn if a deprecated or unavailable declaration is being +/// used, or produce an error (and return true) if a C++0x deleted +/// function is being used. +/// +/// \returns true if there was an error (this declaration cannot be +/// referenced), false otherwise. +/// +bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc, + const ObjCInterfaceDecl *UnknownObjCClass) { + if (getLangOpts().CPlusPlus && isa<FunctionDecl>(D)) { + // If there were any diagnostics suppressed by template argument deduction, + // emit them now. + llvm::DenseMap<Decl *, SmallVector<PartialDiagnosticAt, 1> >::iterator + Pos = SuppressedDiagnostics.find(D->getCanonicalDecl()); + if (Pos != SuppressedDiagnostics.end()) { + SmallVectorImpl<PartialDiagnosticAt> &Suppressed = Pos->second; + for (unsigned I = 0, N = Suppressed.size(); I != N; ++I) + Diag(Suppressed[I].first, Suppressed[I].second); + + // Clear out the list of suppressed diagnostics, so that we don't emit + // them again for this specialization. However, we don't obsolete this + // entry from the table, because we want to avoid ever emitting these + // diagnostics again. + Suppressed.clear(); + } + } + + // See if this is an auto-typed variable whose initializer we are parsing. + if (ParsingInitForAutoVars.count(D)) { + Diag(Loc, diag::err_auto_variable_cannot_appear_in_own_initializer) + << D->getDeclName(); + return true; + } + + // See if this is a deleted function. + if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { + if (FD->isDeleted()) { + Diag(Loc, diag::err_deleted_function_use); + NoteDeletedFunction(FD); + return true; + } + } + DiagnoseAvailabilityOfDecl(*this, D, Loc, UnknownObjCClass); + + // Warn if this is used but marked unused. + if (D->hasAttr<UnusedAttr>()) + Diag(Loc, diag::warn_used_but_marked_unused) << D->getDeclName(); + return false; +} + +/// \brief Retrieve the message suffix that should be added to a +/// diagnostic complaining about the given function being deleted or +/// unavailable. +std::string Sema::getDeletedOrUnavailableSuffix(const FunctionDecl *FD) { + // FIXME: C++0x implicitly-deleted special member functions could be + // detected here so that we could improve diagnostics to say, e.g., + // "base class 'A' had a deleted copy constructor". + if (FD->isDeleted()) + return std::string(); + + std::string Message; + if (FD->getAvailability(&Message)) + return ": " + Message; + + return std::string(); +} + +/// DiagnoseSentinelCalls - This routine checks whether a call or +/// message-send is to a declaration with the sentinel attribute, and +/// if so, it checks that the requirements of the sentinel are +/// satisfied. +void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, + Expr **args, unsigned numArgs) { + const SentinelAttr *attr = D->getAttr<SentinelAttr>(); + if (!attr) + return; + + // The number of formal parameters of the declaration. + unsigned numFormalParams; + + // The kind of declaration. This is also an index into a %select in + // the diagnostic. + enum CalleeType { CT_Function, CT_Method, CT_Block } calleeType; + + if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { + numFormalParams = MD->param_size(); + calleeType = CT_Method; + } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { + numFormalParams = FD->param_size(); + calleeType = CT_Function; + } else if (isa<VarDecl>(D)) { + QualType type = cast<ValueDecl>(D)->getType(); + const FunctionType *fn = 0; + if (const PointerType *ptr = type->getAs<PointerType>()) { + fn = ptr->getPointeeType()->getAs<FunctionType>(); + if (!fn) return; + calleeType = CT_Function; + } else if (const BlockPointerType *ptr = type->getAs<BlockPointerType>()) { + fn = ptr->getPointeeType()->castAs<FunctionType>(); + calleeType = CT_Block; + } else { + return; + } + + if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fn)) { + numFormalParams = proto->getNumArgs(); + } else { + numFormalParams = 0; + } + } else { + return; + } + + // "nullPos" is the number of formal parameters at the end which + // effectively count as part of the variadic arguments. This is + // useful if you would prefer to not have *any* formal parameters, + // but the language forces you to have at least one. + unsigned nullPos = attr->getNullPos(); + assert((nullPos == 0 || nullPos == 1) && "invalid null position on sentinel"); + numFormalParams = (nullPos > numFormalParams ? 0 : numFormalParams - nullPos); + + // The number of arguments which should follow the sentinel. + unsigned numArgsAfterSentinel = attr->getSentinel(); + + // If there aren't enough arguments for all the formal parameters, + // the sentinel, and the args after the sentinel, complain. + if (numArgs < numFormalParams + numArgsAfterSentinel + 1) { + Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); + Diag(D->getLocation(), diag::note_sentinel_here) << calleeType; + return; + } + + // Otherwise, find the sentinel expression. + Expr *sentinelExpr = args[numArgs - numArgsAfterSentinel - 1]; + if (!sentinelExpr) return; + if (sentinelExpr->isValueDependent()) return; + if (Context.isSentinelNullExpr(sentinelExpr)) return; + + // Pick a reasonable string to insert. Optimistically use 'nil' or + // 'NULL' if those are actually defined in the context. Only use + // 'nil' for ObjC methods, where it's much more likely that the + // variadic arguments form a list of object pointers. + SourceLocation MissingNilLoc + = PP.getLocForEndOfToken(sentinelExpr->getLocEnd()); + std::string NullValue; + if (calleeType == CT_Method && + PP.getIdentifierInfo("nil")->hasMacroDefinition()) + NullValue = "nil"; + else if (PP.getIdentifierInfo("NULL")->hasMacroDefinition()) + NullValue = "NULL"; + else + NullValue = "(void*) 0"; + + if (MissingNilLoc.isInvalid()) + Diag(Loc, diag::warn_missing_sentinel) << calleeType; + else + Diag(MissingNilLoc, diag::warn_missing_sentinel) + << calleeType + << FixItHint::CreateInsertion(MissingNilLoc, ", " + NullValue); + Diag(D->getLocation(), diag::note_sentinel_here) << calleeType; +} + +SourceRange Sema::getExprRange(Expr *E) const { + return E ? E->getSourceRange() : SourceRange(); +} + +//===----------------------------------------------------------------------===// +// Standard Promotions and Conversions +//===----------------------------------------------------------------------===// + +/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). +ExprResult Sema::DefaultFunctionArrayConversion(Expr *E) { + // Handle any placeholder expressions which made it here. + if (E->getType()->isPlaceholderType()) { + ExprResult result = CheckPlaceholderExpr(E); + if (result.isInvalid()) return ExprError(); + E = result.take(); + } + + QualType Ty = E->getType(); + assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); + + if (Ty->isFunctionType()) + E = ImpCastExprToType(E, Context.getPointerType(Ty), + CK_FunctionToPointerDecay).take(); + else if (Ty->isArrayType()) { + // In C90 mode, arrays only promote to pointers if the array expression is + // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has + // type 'array of type' is converted to an expression that has type 'pointer + // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression + // that has type 'array of type' ...". The relevant change is "an lvalue" + // (C90) to "an expression" (C99). + // + // C++ 4.2p1: + // An lvalue or rvalue of type "array of N T" or "array of unknown bound of + // T" can be converted to an rvalue of type "pointer to T". + // + if (getLangOpts().C99 || getLangOpts().CPlusPlus || E->isLValue()) + E = ImpCastExprToType(E, Context.getArrayDecayedType(Ty), + CK_ArrayToPointerDecay).take(); + } + return Owned(E); +} + +static void CheckForNullPointerDereference(Sema &S, Expr *E) { + // Check to see if we are dereferencing a null pointer. If so, + // and if not volatile-qualified, this is undefined behavior that the + // optimizer will delete, so warn about it. People sometimes try to use this + // to get a deterministic trap and are surprised by clang's behavior. This + // only handles the pattern "*null", which is a very syntactic check. + if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E->IgnoreParenCasts())) + if (UO->getOpcode() == UO_Deref && + UO->getSubExpr()->IgnoreParenCasts()-> + isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull) && + !UO->getType().isVolatileQualified()) { + S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO, + S.PDiag(diag::warn_indirection_through_null) + << UO->getSubExpr()->getSourceRange()); + S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO, + S.PDiag(diag::note_indirection_through_null)); + } +} + +ExprResult Sema::DefaultLvalueConversion(Expr *E) { + // Handle any placeholder expressions which made it here. + if (E->getType()->isPlaceholderType()) { + ExprResult result = CheckPlaceholderExpr(E); + if (result.isInvalid()) return ExprError(); + E = result.take(); + } + + // C++ [conv.lval]p1: + // A glvalue of a non-function, non-array type T can be + // converted to a prvalue. + if (!E->isGLValue()) return Owned(E); + + QualType T = E->getType(); + assert(!T.isNull() && "r-value conversion on typeless expression?"); + + // We don't want to throw lvalue-to-rvalue casts on top of + // expressions of certain types in C++. + if (getLangOpts().CPlusPlus && + (E->getType() == Context.OverloadTy || + T->isDependentType() || + T->isRecordType())) + return Owned(E); + + // The C standard is actually really unclear on this point, and + // DR106 tells us what the result should be but not why. It's + // generally best to say that void types just doesn't undergo + // lvalue-to-rvalue at all. Note that expressions of unqualified + // 'void' type are never l-values, but qualified void can be. + if (T->isVoidType()) + return Owned(E); + + CheckForNullPointerDereference(*this, E); + + // C++ [conv.lval]p1: + // [...] If T is a non-class type, the type of the prvalue is the + // cv-unqualified version of T. Otherwise, the type of the + // rvalue is T. + // + // C99 6.3.2.1p2: + // If the lvalue has qualified type, the value has the unqualified + // version of the type of the lvalue; otherwise, the value has the + // type of the lvalue. + if (T.hasQualifiers()) + T = T.getUnqualifiedType(); + + UpdateMarkingForLValueToRValue(E); + + ExprResult Res = Owned(ImplicitCastExpr::Create(Context, T, CK_LValueToRValue, + E, 0, VK_RValue)); + + // C11 6.3.2.1p2: + // ... if the lvalue has atomic type, the value has the non-atomic version + // of the type of the lvalue ... + if (const AtomicType *Atomic = T->getAs<AtomicType>()) { + T = Atomic->getValueType().getUnqualifiedType(); + Res = Owned(ImplicitCastExpr::Create(Context, T, CK_AtomicToNonAtomic, + Res.get(), 0, VK_RValue)); + } + + return Res; +} + +ExprResult Sema::DefaultFunctionArrayLvalueConversion(Expr *E) { + ExprResult Res = DefaultFunctionArrayConversion(E); + if (Res.isInvalid()) + return ExprError(); + Res = DefaultLvalueConversion(Res.take()); + if (Res.isInvalid()) + return ExprError(); + return move(Res); +} + + +/// UsualUnaryConversions - Performs various conversions that are common to most +/// operators (C99 6.3). The conversions of array and function types are +/// sometimes suppressed. For example, the array->pointer conversion doesn't +/// apply if the array is an argument to the sizeof or address (&) operators. +/// In these instances, this routine should *not* be called. +ExprResult Sema::UsualUnaryConversions(Expr *E) { + // First, convert to an r-value. + ExprResult Res = DefaultFunctionArrayLvalueConversion(E); + if (Res.isInvalid()) + return Owned(E); + E = Res.take(); + + QualType Ty = E->getType(); + assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); + + // Half FP is a bit different: it's a storage-only type, meaning that any + // "use" of it should be promoted to float. + if (Ty->isHalfType()) + return ImpCastExprToType(Res.take(), Context.FloatTy, CK_FloatingCast); + + // Try to perform integral promotions if the object has a theoretically + // promotable type. + if (Ty->isIntegralOrUnscopedEnumerationType()) { + // C99 6.3.1.1p2: + // + // The following may be used in an expression wherever an int or + // unsigned int may be used: + // - an object or expression with an integer type whose integer + // conversion rank is less than or equal to the rank of int + // and unsigned int. + // - A bit-field of type _Bool, int, signed int, or unsigned int. + // + // If an int can represent all values of the original type, the + // value is converted to an int; otherwise, it is converted to an + // unsigned int. These are called the integer promotions. All + // other types are unchanged by the integer promotions. + + QualType PTy = Context.isPromotableBitField(E); + if (!PTy.isNull()) { + E = ImpCastExprToType(E, PTy, CK_IntegralCast).take(); + return Owned(E); + } + if (Ty->isPromotableIntegerType()) { + QualType PT = Context.getPromotedIntegerType(Ty); + E = ImpCastExprToType(E, PT, CK_IntegralCast).take(); + return Owned(E); + } + } + return Owned(E); +} + +/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that +/// do not have a prototype. Arguments that have type float are promoted to +/// double. All other argument types are converted by UsualUnaryConversions(). +ExprResult Sema::DefaultArgumentPromotion(Expr *E) { + QualType Ty = E->getType(); + assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); + + ExprResult Res = UsualUnaryConversions(E); + if (Res.isInvalid()) + return Owned(E); + E = Res.take(); + + // If this is a 'float' (CVR qualified or typedef) promote to double. + if (Ty->isSpecificBuiltinType(BuiltinType::Float)) + E = ImpCastExprToType(E, Context.DoubleTy, CK_FloatingCast).take(); + + // C++ performs lvalue-to-rvalue conversion as a default argument + // promotion, even on class types, but note: + // C++11 [conv.lval]p2: + // When an lvalue-to-rvalue conversion occurs in an unevaluated + // operand or a subexpression thereof the value contained in the + // referenced object is not accessed. Otherwise, if the glvalue + // has a class type, the conversion copy-initializes a temporary + // of type T from the glvalue and the result of the conversion + // is a prvalue for the temporary. + // FIXME: add some way to gate this entire thing for correctness in + // potentially potentially evaluated contexts. + if (getLangOpts().CPlusPlus && E->isGLValue() && + ExprEvalContexts.back().Context != Unevaluated) { + ExprResult Temp = PerformCopyInitialization( + InitializedEntity::InitializeTemporary(E->getType()), + E->getExprLoc(), + Owned(E)); + if (Temp.isInvalid()) + return ExprError(); + E = Temp.get(); + } + + return Owned(E); +} + +/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but +/// will warn if the resulting type is not a POD type, and rejects ObjC +/// interfaces passed by value. +ExprResult Sema::DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT, + FunctionDecl *FDecl) { + if (const BuiltinType *PlaceholderTy = E->getType()->getAsPlaceholderType()) { + // Strip the unbridged-cast placeholder expression off, if applicable. + if (PlaceholderTy->getKind() == BuiltinType::ARCUnbridgedCast && + (CT == VariadicMethod || + (FDecl && FDecl->hasAttr<CFAuditedTransferAttr>()))) { + E = stripARCUnbridgedCast(E); + + // Otherwise, do normal placeholder checking. + } else { + ExprResult ExprRes = CheckPlaceholderExpr(E); + if (ExprRes.isInvalid()) + return ExprError(); + E = ExprRes.take(); + } + } + + ExprResult ExprRes = DefaultArgumentPromotion(E); + if (ExprRes.isInvalid()) + return ExprError(); + E = ExprRes.take(); + + // Don't allow one to pass an Objective-C interface to a vararg. + if (E->getType()->isObjCObjectType() && + DiagRuntimeBehavior(E->getLocStart(), 0, + PDiag(diag::err_cannot_pass_objc_interface_to_vararg) + << E->getType() << CT)) + return ExprError(); + + // Complain about passing non-POD types through varargs. However, don't + // perform this check for incomplete types, which we can get here when we're + // in an unevaluated context. + if (!E->getType()->isIncompleteType() && !E->getType().isPODType(Context)) { + // C++0x [expr.call]p7: + // Passing a potentially-evaluated argument of class type (Clause 9) + // having a non-trivial copy constructor, a non-trivial move constructor, + // or a non-trivial destructor, with no corresponding parameter, + // is conditionally-supported with implementation-defined semantics. + bool TrivialEnough = false; + if (getLangOpts().CPlusPlus0x && !E->getType()->isDependentType()) { + if (CXXRecordDecl *Record = E->getType()->getAsCXXRecordDecl()) { + if (Record->hasTrivialCopyConstructor() && + Record->hasTrivialMoveConstructor() && + Record->hasTrivialDestructor()) { + DiagRuntimeBehavior(E->getLocStart(), 0, + PDiag(diag::warn_cxx98_compat_pass_non_pod_arg_to_vararg) + << E->getType() << CT); + TrivialEnough = true; + } + } + } + + if (!TrivialEnough && + getLangOpts().ObjCAutoRefCount && + E->getType()->isObjCLifetimeType()) + TrivialEnough = true; + + if (TrivialEnough) { + // Nothing to diagnose. This is okay. + } else if (DiagRuntimeBehavior(E->getLocStart(), 0, + PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) + << getLangOpts().CPlusPlus0x << E->getType() + << CT)) { + // Turn this into a trap. + CXXScopeSpec SS; + SourceLocation TemplateKWLoc; + UnqualifiedId Name; + Name.setIdentifier(PP.getIdentifierInfo("__builtin_trap"), + E->getLocStart()); + ExprResult TrapFn = ActOnIdExpression(TUScope, SS, TemplateKWLoc, Name, + true, false); + if (TrapFn.isInvalid()) + return ExprError(); + + ExprResult Call = ActOnCallExpr(TUScope, TrapFn.get(), E->getLocStart(), + MultiExprArg(), E->getLocEnd()); + if (Call.isInvalid()) + return ExprError(); + + ExprResult Comma = ActOnBinOp(TUScope, E->getLocStart(), tok::comma, + Call.get(), E); + if (Comma.isInvalid()) + return ExprError(); + E = Comma.get(); + } + } + // c++ rules are enforced elsewhere. + if (!getLangOpts().CPlusPlus && + RequireCompleteType(E->getExprLoc(), E->getType(), + diag::err_call_incomplete_argument)) + return ExprError(); + + return Owned(E); +} + +/// \brief Converts an integer to complex float type. Helper function of +/// UsualArithmeticConversions() +/// +/// \return false if the integer expression is an integer type and is +/// successfully converted to the complex type. +static bool handleIntegerToComplexFloatConversion(Sema &S, ExprResult &IntExpr, + ExprResult &ComplexExpr, + QualType IntTy, + QualType ComplexTy, + bool SkipCast) { + if (IntTy->isComplexType() || IntTy->isRealFloatingType()) return true; + if (SkipCast) return false; + if (IntTy->isIntegerType()) { + QualType fpTy = cast<ComplexType>(ComplexTy)->getElementType(); + IntExpr = S.ImpCastExprToType(IntExpr.take(), fpTy, CK_IntegralToFloating); + IntExpr = S.ImpCastExprToType(IntExpr.take(), ComplexTy, + CK_FloatingRealToComplex); + } else { + assert(IntTy->isComplexIntegerType()); + IntExpr = S.ImpCastExprToType(IntExpr.take(), ComplexTy, + CK_IntegralComplexToFloatingComplex); + } + return false; +} + +/// \brief Takes two complex float types and converts them to the same type. +/// Helper function of UsualArithmeticConversions() +static QualType +handleComplexFloatToComplexFloatConverstion(Sema &S, ExprResult &LHS, + ExprResult &RHS, QualType LHSType, + QualType RHSType, + bool IsCompAssign) { + int order = S.Context.getFloatingTypeOrder(LHSType, RHSType); + + if (order < 0) { + // _Complex float -> _Complex double + if (!IsCompAssign) + LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_FloatingComplexCast); + return RHSType; + } + if (order > 0) + // _Complex float -> _Complex double + RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_FloatingComplexCast); + return LHSType; +} + +/// \brief Converts otherExpr to complex float and promotes complexExpr if +/// necessary. Helper function of UsualArithmeticConversions() +static QualType handleOtherComplexFloatConversion(Sema &S, + ExprResult &ComplexExpr, + ExprResult &OtherExpr, + QualType ComplexTy, + QualType OtherTy, + bool ConvertComplexExpr, + bool ConvertOtherExpr) { + int order = S.Context.getFloatingTypeOrder(ComplexTy, OtherTy); + + // If just the complexExpr is complex, the otherExpr needs to be converted, + // and the complexExpr might need to be promoted. + if (order > 0) { // complexExpr is wider + // float -> _Complex double + if (ConvertOtherExpr) { + QualType fp = cast<ComplexType>(ComplexTy)->getElementType(); + OtherExpr = S.ImpCastExprToType(OtherExpr.take(), fp, CK_FloatingCast); + OtherExpr = S.ImpCastExprToType(OtherExpr.take(), ComplexTy, + CK_FloatingRealToComplex); + } + return ComplexTy; + } + + // otherTy is at least as wide. Find its corresponding complex type. + QualType result = (order == 0 ? ComplexTy : + S.Context.getComplexType(OtherTy)); + + // double -> _Complex double + if (ConvertOtherExpr) + OtherExpr = S.ImpCastExprToType(OtherExpr.take(), result, + CK_FloatingRealToComplex); + + // _Complex float -> _Complex double + if (ConvertComplexExpr && order < 0) + ComplexExpr = S.ImpCastExprToType(ComplexExpr.take(), result, + CK_FloatingComplexCast); + + return result; +} + +/// \brief Handle arithmetic conversion with complex types. Helper function of +/// UsualArithmeticConversions() +static QualType handleComplexFloatConversion(Sema &S, ExprResult &LHS, + ExprResult &RHS, QualType LHSType, + QualType RHSType, + bool IsCompAssign) { + // if we have an integer operand, the result is the complex type. + if (!handleIntegerToComplexFloatConversion(S, RHS, LHS, RHSType, LHSType, + /*skipCast*/false)) + return LHSType; + if (!handleIntegerToComplexFloatConversion(S, LHS, RHS, LHSType, RHSType, + /*skipCast*/IsCompAssign)) + return RHSType; + + // This handles complex/complex, complex/float, or float/complex. + // When both operands are complex, the shorter operand is converted to the + // type of the longer, and that is the type of the result. This corresponds + // to what is done when combining two real floating-point operands. + // The fun begins when size promotion occur across type domains. + // From H&S 6.3.4: When one operand is complex and the other is a real + // floating-point type, the less precise type is converted, within it's + // real or complex domain, to the precision of the other type. For example, + // when combining a "long double" with a "double _Complex", the + // "double _Complex" is promoted to "long double _Complex". + + bool LHSComplexFloat = LHSType->isComplexType(); + bool RHSComplexFloat = RHSType->isComplexType(); + + // If both are complex, just cast to the more precise type. + if (LHSComplexFloat && RHSComplexFloat) + return handleComplexFloatToComplexFloatConverstion(S, LHS, RHS, + LHSType, RHSType, + IsCompAssign); + + // If only one operand is complex, promote it if necessary and convert the + // other operand to complex. + if (LHSComplexFloat) + return handleOtherComplexFloatConversion( + S, LHS, RHS, LHSType, RHSType, /*convertComplexExpr*/!IsCompAssign, + /*convertOtherExpr*/ true); + + assert(RHSComplexFloat); + return handleOtherComplexFloatConversion( + S, RHS, LHS, RHSType, LHSType, /*convertComplexExpr*/true, + /*convertOtherExpr*/ !IsCompAssign); +} + +/// \brief Hande arithmetic conversion from integer to float. Helper function +/// of UsualArithmeticConversions() +static QualType handleIntToFloatConversion(Sema &S, ExprResult &FloatExpr, + ExprResult &IntExpr, + QualType FloatTy, QualType IntTy, + bool ConvertFloat, bool ConvertInt) { + if (IntTy->isIntegerType()) { + if (ConvertInt) + // Convert intExpr to the lhs floating point type. + IntExpr = S.ImpCastExprToType(IntExpr.take(), FloatTy, + CK_IntegralToFloating); + return FloatTy; + } + + // Convert both sides to the appropriate complex float. + assert(IntTy->isComplexIntegerType()); + QualType result = S.Context.getComplexType(FloatTy); + + // _Complex int -> _Complex float + if (ConvertInt) + IntExpr = S.ImpCastExprToType(IntExpr.take(), result, + CK_IntegralComplexToFloatingComplex); + + // float -> _Complex float + if (ConvertFloat) + FloatExpr = S.ImpCastExprToType(FloatExpr.take(), result, + CK_FloatingRealToComplex); + + return result; +} + +/// \brief Handle arithmethic conversion with floating point types. Helper +/// function of UsualArithmeticConversions() +static QualType handleFloatConversion(Sema &S, ExprResult &LHS, + ExprResult &RHS, QualType LHSType, + QualType RHSType, bool IsCompAssign) { + bool LHSFloat = LHSType->isRealFloatingType(); + bool RHSFloat = RHSType->isRealFloatingType(); + + // If we have two real floating types, convert the smaller operand + // to the bigger result. + if (LHSFloat && RHSFloat) { + int order = S.Context.getFloatingTypeOrder(LHSType, RHSType); + if (order > 0) { + RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_FloatingCast); + return LHSType; + } + + assert(order < 0 && "illegal float comparison"); + if (!IsCompAssign) + LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_FloatingCast); + return RHSType; + } + + if (LHSFloat) + return handleIntToFloatConversion(S, LHS, RHS, LHSType, RHSType, + /*convertFloat=*/!IsCompAssign, + /*convertInt=*/ true); + assert(RHSFloat); + return handleIntToFloatConversion(S, RHS, LHS, RHSType, LHSType, + /*convertInt=*/ true, + /*convertFloat=*/!IsCompAssign); +} + +/// \brief Handle conversions with GCC complex int extension. Helper function +/// of UsualArithmeticConversions() +// FIXME: if the operands are (int, _Complex long), we currently +// don't promote the complex. Also, signedness? +static QualType handleComplexIntConversion(Sema &S, ExprResult &LHS, + ExprResult &RHS, QualType LHSType, + QualType RHSType, + bool IsCompAssign) { + const ComplexType *LHSComplexInt = LHSType->getAsComplexIntegerType(); + const ComplexType *RHSComplexInt = RHSType->getAsComplexIntegerType(); + + if (LHSComplexInt && RHSComplexInt) { + int order = S.Context.getIntegerTypeOrder(LHSComplexInt->getElementType(), + RHSComplexInt->getElementType()); + assert(order && "inequal types with equal element ordering"); + if (order > 0) { + // _Complex int -> _Complex long + RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralComplexCast); + return LHSType; + } + + if (!IsCompAssign) + LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralComplexCast); + return RHSType; + } + + if (LHSComplexInt) { + // int -> _Complex int + // FIXME: This needs to take integer ranks into account + RHS = S.ImpCastExprToType(RHS.take(), LHSComplexInt->getElementType(), + CK_IntegralCast); + RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralRealToComplex); + return LHSType; + } + + assert(RHSComplexInt); + // int -> _Complex int + // FIXME: This needs to take integer ranks into account + if (!IsCompAssign) { + LHS = S.ImpCastExprToType(LHS.take(), RHSComplexInt->getElementType(), + CK_IntegralCast); + LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralRealToComplex); + } + return RHSType; +} + +/// \brief Handle integer arithmetic conversions. Helper function of +/// UsualArithmeticConversions() +static QualType handleIntegerConversion(Sema &S, ExprResult &LHS, + ExprResult &RHS, QualType LHSType, + QualType RHSType, bool IsCompAssign) { + // The rules for this case are in C99 6.3.1.8 + int order = S.Context.getIntegerTypeOrder(LHSType, RHSType); + bool LHSSigned = LHSType->hasSignedIntegerRepresentation(); + bool RHSSigned = RHSType->hasSignedIntegerRepresentation(); + if (LHSSigned == RHSSigned) { + // Same signedness; use the higher-ranked type + if (order >= 0) { + RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralCast); + return LHSType; + } else if (!IsCompAssign) + LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralCast); + return RHSType; + } else if (order != (LHSSigned ? 1 : -1)) { + // The unsigned type has greater than or equal rank to the + // signed type, so use the unsigned type + if (RHSSigned) { + RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralCast); + return LHSType; + } else if (!IsCompAssign) + LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralCast); + return RHSType; + } else if (S.Context.getIntWidth(LHSType) != S.Context.getIntWidth(RHSType)) { + // The two types are different widths; if we are here, that + // means the signed type is larger than the unsigned type, so + // use the signed type. + if (LHSSigned) { + RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralCast); + return LHSType; + } else if (!IsCompAssign) + LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralCast); + return RHSType; + } else { + // The signed type is higher-ranked than the unsigned type, + // but isn't actually any bigger (like unsigned int and long + // on most 32-bit systems). Use the unsigned type corresponding + // to the signed type. + QualType result = + S.Context.getCorrespondingUnsignedType(LHSSigned ? LHSType : RHSType); + RHS = S.ImpCastExprToType(RHS.take(), result, CK_IntegralCast); + if (!IsCompAssign) + LHS = S.ImpCastExprToType(LHS.take(), result, CK_IntegralCast); + return result; + } +} + +/// UsualArithmeticConversions - Performs various conversions that are common to +/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this +/// routine returns the first non-arithmetic type found. The client is +/// responsible for emitting appropriate error diagnostics. +/// FIXME: verify the conversion rules for "complex int" are consistent with +/// GCC. +QualType Sema::UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS, + bool IsCompAssign) { + if (!IsCompAssign) { + LHS = UsualUnaryConversions(LHS.take()); + if (LHS.isInvalid()) + return QualType(); + } + + RHS = UsualUnaryConversions(RHS.take()); + if (RHS.isInvalid()) + return QualType(); + + // For conversion purposes, we ignore any qualifiers. + // For example, "const float" and "float" are equivalent. + QualType LHSType = + Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType(); + QualType RHSType = + Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType(); + + // If both types are identical, no conversion is needed. + if (LHSType == RHSType) + return LHSType; + + // If either side is a non-arithmetic type (e.g. a pointer), we are done. + // The caller can deal with this (e.g. pointer + int). + if (!LHSType->isArithmeticType() || !RHSType->isArithmeticType()) + return LHSType; + + // Apply unary and bitfield promotions to the LHS's type. + QualType LHSUnpromotedType = LHSType; + if (LHSType->isPromotableIntegerType()) + LHSType = Context.getPromotedIntegerType(LHSType); + QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(LHS.get()); + if (!LHSBitfieldPromoteTy.isNull()) + LHSType = LHSBitfieldPromoteTy; + if (LHSType != LHSUnpromotedType && !IsCompAssign) + LHS = ImpCastExprToType(LHS.take(), LHSType, CK_IntegralCast); + + // If both types are identical, no conversion is needed. + if (LHSType == RHSType) + return LHSType; + + // At this point, we have two different arithmetic types. + + // Handle complex types first (C99 6.3.1.8p1). + if (LHSType->isComplexType() || RHSType->isComplexType()) + return handleComplexFloatConversion(*this, LHS, RHS, LHSType, RHSType, + IsCompAssign); + + // Now handle "real" floating types (i.e. float, double, long double). + if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType()) + return handleFloatConversion(*this, LHS, RHS, LHSType, RHSType, + IsCompAssign); + + // Handle GCC complex int extension. + if (LHSType->isComplexIntegerType() || RHSType->isComplexIntegerType()) + return handleComplexIntConversion(*this, LHS, RHS, LHSType, RHSType, + IsCompAssign); + + // Finally, we have two differing integer types. + return handleIntegerConversion(*this, LHS, RHS, LHSType, RHSType, + IsCompAssign); +} + +//===----------------------------------------------------------------------===// +// Semantic Analysis for various Expression Types +//===----------------------------------------------------------------------===// + + +ExprResult +Sema::ActOnGenericSelectionExpr(SourceLocation KeyLoc, + SourceLocation DefaultLoc, + SourceLocation RParenLoc, + Expr *ControllingExpr, + MultiTypeArg ArgTypes, + MultiExprArg ArgExprs) { + unsigned NumAssocs = ArgTypes.size(); + assert(NumAssocs == ArgExprs.size()); + + ParsedType *ParsedTypes = ArgTypes.release(); + Expr **Exprs = ArgExprs.release(); + + TypeSourceInfo **Types = new TypeSourceInfo*[NumAssocs]; + for (unsigned i = 0; i < NumAssocs; ++i) { + if (ParsedTypes[i]) + (void) GetTypeFromParser(ParsedTypes[i], &Types[i]); + else + Types[i] = 0; + } + + ExprResult ER = CreateGenericSelectionExpr(KeyLoc, DefaultLoc, RParenLoc, + ControllingExpr, Types, Exprs, + NumAssocs); + delete [] Types; + return ER; +} + +ExprResult +Sema::CreateGenericSelectionExpr(SourceLocation KeyLoc, + SourceLocation DefaultLoc, + SourceLocation RParenLoc, + Expr *ControllingExpr, + TypeSourceInfo **Types, + Expr **Exprs, + unsigned NumAssocs) { + bool TypeErrorFound = false, + IsResultDependent = ControllingExpr->isTypeDependent(), + ContainsUnexpandedParameterPack + = ControllingExpr->containsUnexpandedParameterPack(); + + for (unsigned i = 0; i < NumAssocs; ++i) { + if (Exprs[i]->containsUnexpandedParameterPack()) + ContainsUnexpandedParameterPack = true; + + if (Types[i]) { + if (Types[i]->getType()->containsUnexpandedParameterPack()) + ContainsUnexpandedParameterPack = true; + + if (Types[i]->getType()->isDependentType()) { + IsResultDependent = true; + } else { + // C11 6.5.1.1p2 "The type name in a generic association shall specify a + // complete object type other than a variably modified type." + unsigned D = 0; + if (Types[i]->getType()->isIncompleteType()) + D = diag::err_assoc_type_incomplete; + else if (!Types[i]->getType()->isObjectType()) + D = diag::err_assoc_type_nonobject; + else if (Types[i]->getType()->isVariablyModifiedType()) + D = diag::err_assoc_type_variably_modified; + + if (D != 0) { + Diag(Types[i]->getTypeLoc().getBeginLoc(), D) + << Types[i]->getTypeLoc().getSourceRange() + << Types[i]->getType(); + TypeErrorFound = true; + } + + // C11 6.5.1.1p2 "No two generic associations in the same generic + // selection shall specify compatible types." + for (unsigned j = i+1; j < NumAssocs; ++j) + if (Types[j] && !Types[j]->getType()->isDependentType() && + Context.typesAreCompatible(Types[i]->getType(), + Types[j]->getType())) { + Diag(Types[j]->getTypeLoc().getBeginLoc(), + diag::err_assoc_compatible_types) + << Types[j]->getTypeLoc().getSourceRange() + << Types[j]->getType() + << Types[i]->getType(); + Diag(Types[i]->getTypeLoc().getBeginLoc(), + diag::note_compat_assoc) + << Types[i]->getTypeLoc().getSourceRange() + << Types[i]->getType(); + TypeErrorFound = true; + } + } + } + } + if (TypeErrorFound) + return ExprError(); + + // If we determined that the generic selection is result-dependent, don't + // try to compute the result expression. + if (IsResultDependent) + return Owned(new (Context) GenericSelectionExpr( + Context, KeyLoc, ControllingExpr, + Types, Exprs, NumAssocs, DefaultLoc, + RParenLoc, ContainsUnexpandedParameterPack)); + + SmallVector<unsigned, 1> CompatIndices; + unsigned DefaultIndex = -1U; + for (unsigned i = 0; i < NumAssocs; ++i) { + if (!Types[i]) + DefaultIndex = i; + else if (Context.typesAreCompatible(ControllingExpr->getType(), + Types[i]->getType())) + CompatIndices.push_back(i); + } + + // C11 6.5.1.1p2 "The controlling expression of a generic selection shall have + // type compatible with at most one of the types named in its generic + // association list." + if (CompatIndices.size() > 1) { + // We strip parens here because the controlling expression is typically + // parenthesized in macro definitions. + ControllingExpr = ControllingExpr->IgnoreParens(); + Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_multi_match) + << ControllingExpr->getSourceRange() << ControllingExpr->getType() + << (unsigned) CompatIndices.size(); + for (SmallVector<unsigned, 1>::iterator I = CompatIndices.begin(), + E = CompatIndices.end(); I != E; ++I) { + Diag(Types[*I]->getTypeLoc().getBeginLoc(), + diag::note_compat_assoc) + << Types[*I]->getTypeLoc().getSourceRange() + << Types[*I]->getType(); + } + return ExprError(); + } + + // C11 6.5.1.1p2 "If a generic selection has no default generic association, + // its controlling expression shall have type compatible with exactly one of + // the types named in its generic association list." + if (DefaultIndex == -1U && CompatIndices.size() == 0) { + // We strip parens here because the controlling expression is typically + // parenthesized in macro definitions. + ControllingExpr = ControllingExpr->IgnoreParens(); + Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_no_match) + << ControllingExpr->getSourceRange() << ControllingExpr->getType(); + return ExprError(); + } + + // C11 6.5.1.1p3 "If a generic selection has a generic association with a + // type name that is compatible with the type of the controlling expression, + // then the result expression of the generic selection is the expression + // in that generic association. Otherwise, the result expression of the + // generic selection is the expression in the default generic association." + unsigned ResultIndex = + CompatIndices.size() ? CompatIndices[0] : DefaultIndex; + + return Owned(new (Context) GenericSelectionExpr( + Context, KeyLoc, ControllingExpr, + Types, Exprs, NumAssocs, DefaultLoc, + RParenLoc, ContainsUnexpandedParameterPack, + ResultIndex)); +} + +/// getUDSuffixLoc - Create a SourceLocation for a ud-suffix, given the +/// location of the token and the offset of the ud-suffix within it. +static SourceLocation getUDSuffixLoc(Sema &S, SourceLocation TokLoc, + unsigned Offset) { + return Lexer::AdvanceToTokenCharacter(TokLoc, Offset, S.getSourceManager(), + S.getLangOpts()); +} + +/// BuildCookedLiteralOperatorCall - A user-defined literal was found. Look up +/// the corresponding cooked (non-raw) literal operator, and build a call to it. +static ExprResult BuildCookedLiteralOperatorCall(Sema &S, Scope *Scope, + IdentifierInfo *UDSuffix, + SourceLocation UDSuffixLoc, + ArrayRef<Expr*> Args, + SourceLocation LitEndLoc) { + assert(Args.size() <= 2 && "too many arguments for literal operator"); + + QualType ArgTy[2]; + for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) { + ArgTy[ArgIdx] = Args[ArgIdx]->getType(); + if (ArgTy[ArgIdx]->isArrayType()) + ArgTy[ArgIdx] = S.Context.getArrayDecayedType(ArgTy[ArgIdx]); + } + + DeclarationName OpName = + S.Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix); + DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc); + OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc); + + LookupResult R(S, OpName, UDSuffixLoc, Sema::LookupOrdinaryName); + if (S.LookupLiteralOperator(Scope, R, llvm::makeArrayRef(ArgTy, Args.size()), + /*AllowRawAndTemplate*/false) == Sema::LOLR_Error) + return ExprError(); + + return S.BuildLiteralOperatorCall(R, OpNameInfo, Args, LitEndLoc); +} + +/// ActOnStringLiteral - The specified tokens were lexed as pasted string +/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string +/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from +/// multiple tokens. However, the common case is that StringToks points to one +/// string. +/// +ExprResult +Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks, + Scope *UDLScope) { + assert(NumStringToks && "Must have at least one string!"); + + StringLiteralParser Literal(StringToks, NumStringToks, PP); + if (Literal.hadError) + return ExprError(); + + SmallVector<SourceLocation, 4> StringTokLocs; + for (unsigned i = 0; i != NumStringToks; ++i) + StringTokLocs.push_back(StringToks[i].getLocation()); + + QualType StrTy = Context.CharTy; + if (Literal.isWide()) + StrTy = Context.getWCharType(); + else if (Literal.isUTF16()) + StrTy = Context.Char16Ty; + else if (Literal.isUTF32()) + StrTy = Context.Char32Ty; + else if (Literal.isPascal()) + StrTy = Context.UnsignedCharTy; + + StringLiteral::StringKind Kind = StringLiteral::Ascii; + if (Literal.isWide()) + Kind = StringLiteral::Wide; + else if (Literal.isUTF8()) + Kind = StringLiteral::UTF8; + else if (Literal.isUTF16()) + Kind = StringLiteral::UTF16; + else if (Literal.isUTF32()) + Kind = StringLiteral::UTF32; + + // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). + if (getLangOpts().CPlusPlus || getLangOpts().ConstStrings) + StrTy.addConst(); + + // Get an array type for the string, according to C99 6.4.5. This includes + // the nul terminator character as well as the string length for pascal + // strings. + StrTy = Context.getConstantArrayType(StrTy, + llvm::APInt(32, Literal.GetNumStringChars()+1), + ArrayType::Normal, 0); + + // Pass &StringTokLocs[0], StringTokLocs.size() to factory! + StringLiteral *Lit = StringLiteral::Create(Context, Literal.GetString(), + Kind, Literal.Pascal, StrTy, + &StringTokLocs[0], + StringTokLocs.size()); + if (Literal.getUDSuffix().empty()) + return Owned(Lit); + + // We're building a user-defined literal. + IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix()); + SourceLocation UDSuffixLoc = + getUDSuffixLoc(*this, StringTokLocs[Literal.getUDSuffixToken()], + Literal.getUDSuffixOffset()); + + // Make sure we're allowed user-defined literals here. + if (!UDLScope) + return ExprError(Diag(UDSuffixLoc, diag::err_invalid_string_udl)); + + // C++11 [lex.ext]p5: The literal L is treated as a call of the form + // operator "" X (str, len) + QualType SizeType = Context.getSizeType(); + llvm::APInt Len(Context.getIntWidth(SizeType), Literal.GetNumStringChars()); + IntegerLiteral *LenArg = IntegerLiteral::Create(Context, Len, SizeType, + StringTokLocs[0]); + Expr *Args[] = { Lit, LenArg }; + return BuildCookedLiteralOperatorCall(*this, UDLScope, UDSuffix, UDSuffixLoc, + Args, StringTokLocs.back()); +} + +ExprResult +Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, + SourceLocation Loc, + const CXXScopeSpec *SS) { + DeclarationNameInfo NameInfo(D->getDeclName(), Loc); + return BuildDeclRefExpr(D, Ty, VK, NameInfo, SS); +} + +/// BuildDeclRefExpr - Build an expression that references a +/// declaration that does not require a closure capture. +ExprResult +Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, + const DeclarationNameInfo &NameInfo, + const CXXScopeSpec *SS) { + if (getLangOpts().CUDA) + if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext)) + if (const FunctionDecl *Callee = dyn_cast<FunctionDecl>(D)) { + CUDAFunctionTarget CallerTarget = IdentifyCUDATarget(Caller), + CalleeTarget = IdentifyCUDATarget(Callee); + if (CheckCUDATarget(CallerTarget, CalleeTarget)) { + Diag(NameInfo.getLoc(), diag::err_ref_bad_target) + << CalleeTarget << D->getIdentifier() << CallerTarget; + Diag(D->getLocation(), diag::note_previous_decl) + << D->getIdentifier(); + return ExprError(); + } + } + + bool refersToEnclosingScope = + (CurContext != D->getDeclContext() && + D->getDeclContext()->isFunctionOrMethod()); + + DeclRefExpr *E = DeclRefExpr::Create(Context, + SS ? SS->getWithLocInContext(Context) + : NestedNameSpecifierLoc(), + SourceLocation(), + D, refersToEnclosingScope, + NameInfo, Ty, VK); + + MarkDeclRefReferenced(E); + + // Just in case we're building an illegal pointer-to-member. + FieldDecl *FD = dyn_cast<FieldDecl>(D); + if (FD && FD->isBitField()) + E->setObjectKind(OK_BitField); + + return Owned(E); +} + +/// Decomposes the given name into a DeclarationNameInfo, its location, and +/// possibly a list of template arguments. +/// +/// If this produces template arguments, it is permitted to call +/// DecomposeTemplateName. +/// +/// This actually loses a lot of source location information for +/// non-standard name kinds; we should consider preserving that in +/// some way. +void +Sema::DecomposeUnqualifiedId(const UnqualifiedId &Id, + TemplateArgumentListInfo &Buffer, + DeclarationNameInfo &NameInfo, + const TemplateArgumentListInfo *&TemplateArgs) { + if (Id.getKind() == UnqualifiedId::IK_TemplateId) { + Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); + Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); + + ASTTemplateArgsPtr TemplateArgsPtr(*this, + Id.TemplateId->getTemplateArgs(), + Id.TemplateId->NumArgs); + translateTemplateArguments(TemplateArgsPtr, Buffer); + TemplateArgsPtr.release(); + + TemplateName TName = Id.TemplateId->Template.get(); + SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc; + NameInfo = Context.getNameForTemplate(TName, TNameLoc); + TemplateArgs = &Buffer; + } else { + NameInfo = GetNameFromUnqualifiedId(Id); + TemplateArgs = 0; + } +} + +/// Diagnose an empty lookup. +/// +/// \return false if new lookup candidates were found +bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R, + CorrectionCandidateCallback &CCC, + TemplateArgumentListInfo *ExplicitTemplateArgs, + llvm::ArrayRef<Expr *> Args) { + DeclarationName Name = R.getLookupName(); + + unsigned diagnostic = diag::err_undeclared_var_use; + unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; + if (Name.getNameKind() == DeclarationName::CXXOperatorName || + Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || + Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { + diagnostic = diag::err_undeclared_use; + diagnostic_suggest = diag::err_undeclared_use_suggest; + } + + // If the original lookup was an unqualified lookup, fake an + // unqualified lookup. This is useful when (for example) the + // original lookup would not have found something because it was a + // dependent name. + DeclContext *DC = SS.isEmpty() ? CurContext : 0; + while (DC) { + if (isa<CXXRecordDecl>(DC)) { + LookupQualifiedName(R, DC); + + if (!R.empty()) { + // Don't give errors about ambiguities in this lookup. + R.suppressDiagnostics(); + + // During a default argument instantiation the CurContext points + // to a CXXMethodDecl; but we can't apply a this-> fixit inside a + // function parameter list, hence add an explicit check. + bool isDefaultArgument = !ActiveTemplateInstantiations.empty() && + ActiveTemplateInstantiations.back().Kind == + ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation; + CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); + bool isInstance = CurMethod && + CurMethod->isInstance() && + DC == CurMethod->getParent() && !isDefaultArgument; + + + // Give a code modification hint to insert 'this->'. + // TODO: fixit for inserting 'Base<T>::' in the other cases. + // Actually quite difficult! + if (isInstance) { + UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>( + CallsUndergoingInstantiation.back()->getCallee()); + CXXMethodDecl *DepMethod = cast_or_null<CXXMethodDecl>( + CurMethod->getInstantiatedFromMemberFunction()); + if (DepMethod) { + if (getLangOpts().MicrosoftMode) + diagnostic = diag::warn_found_via_dependent_bases_lookup; + Diag(R.getNameLoc(), diagnostic) << Name + << FixItHint::CreateInsertion(R.getNameLoc(), "this->"); + QualType DepThisType = DepMethod->getThisType(Context); + CheckCXXThisCapture(R.getNameLoc()); + CXXThisExpr *DepThis = new (Context) CXXThisExpr( + R.getNameLoc(), DepThisType, false); + TemplateArgumentListInfo TList; + if (ULE->hasExplicitTemplateArgs()) + ULE->copyTemplateArgumentsInto(TList); + + CXXScopeSpec SS; + SS.Adopt(ULE->getQualifierLoc()); + CXXDependentScopeMemberExpr *DepExpr = + CXXDependentScopeMemberExpr::Create( + Context, DepThis, DepThisType, true, SourceLocation(), + SS.getWithLocInContext(Context), + ULE->getTemplateKeywordLoc(), 0, + R.getLookupNameInfo(), + ULE->hasExplicitTemplateArgs() ? &TList : 0); + CallsUndergoingInstantiation.back()->setCallee(DepExpr); + } else { + // FIXME: we should be able to handle this case too. It is correct + // to add this-> here. This is a workaround for PR7947. + Diag(R.getNameLoc(), diagnostic) << Name; + } + } else { + if (getLangOpts().MicrosoftMode) + diagnostic = diag::warn_found_via_dependent_bases_lookup; + Diag(R.getNameLoc(), diagnostic) << Name; + } + + // Do we really want to note all of these? + for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) + Diag((*I)->getLocation(), diag::note_dependent_var_use); + + // Return true if we are inside a default argument instantiation + // and the found name refers to an instance member function, otherwise + // the function calling DiagnoseEmptyLookup will try to create an + // implicit member call and this is wrong for default argument. + if (isDefaultArgument && ((*R.begin())->isCXXInstanceMember())) { + Diag(R.getNameLoc(), diag::err_member_call_without_object); + return true; + } + + // Tell the callee to try to recover. + return false; + } + + R.clear(); + } + + // In Microsoft mode, if we are performing lookup from within a friend + // function definition declared at class scope then we must set + // DC to the lexical parent to be able to search into the parent + // class. + if (getLangOpts().MicrosoftMode && isa<FunctionDecl>(DC) && + cast<FunctionDecl>(DC)->getFriendObjectKind() && + DC->getLexicalParent()->isRecord()) + DC = DC->getLexicalParent(); + else + DC = DC->getParent(); + } + + // We didn't find anything, so try to correct for a typo. + TypoCorrection Corrected; + if (S && (Corrected = CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), + S, &SS, CCC))) { + std::string CorrectedStr(Corrected.getAsString(getLangOpts())); + std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOpts())); + R.setLookupName(Corrected.getCorrection()); + + if (NamedDecl *ND = Corrected.getCorrectionDecl()) { + if (Corrected.isOverloaded()) { + OverloadCandidateSet OCS(R.getNameLoc()); + OverloadCandidateSet::iterator Best; + for (TypoCorrection::decl_iterator CD = Corrected.begin(), + CDEnd = Corrected.end(); + CD != CDEnd; ++CD) { + if (FunctionTemplateDecl *FTD = + dyn_cast<FunctionTemplateDecl>(*CD)) + AddTemplateOverloadCandidate( + FTD, DeclAccessPair::make(FTD, AS_none), ExplicitTemplateArgs, + Args, OCS); + else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*CD)) + if (!ExplicitTemplateArgs || ExplicitTemplateArgs->size() == 0) + AddOverloadCandidate(FD, DeclAccessPair::make(FD, AS_none), + Args, OCS); + } + switch (OCS.BestViableFunction(*this, R.getNameLoc(), Best)) { + case OR_Success: + ND = Best->Function; + break; + default: + break; + } + } + R.addDecl(ND); + if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)) { + if (SS.isEmpty()) + Diag(R.getNameLoc(), diagnostic_suggest) << Name << CorrectedQuotedStr + << FixItHint::CreateReplacement(R.getNameLoc(), CorrectedStr); + else + Diag(R.getNameLoc(), diag::err_no_member_suggest) + << Name << computeDeclContext(SS, false) << CorrectedQuotedStr + << SS.getRange() + << FixItHint::CreateReplacement(R.getNameLoc(), CorrectedStr); + if (ND) + Diag(ND->getLocation(), diag::note_previous_decl) + << CorrectedQuotedStr; + + // Tell the callee to try to recover. + return false; + } + + if (isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND)) { + // FIXME: If we ended up with a typo for a type name or + // Objective-C class name, we're in trouble because the parser + // is in the wrong place to recover. Suggest the typo + // correction, but don't make it a fix-it since we're not going + // to recover well anyway. + if (SS.isEmpty()) + Diag(R.getNameLoc(), diagnostic_suggest) + << Name << CorrectedQuotedStr; + else + Diag(R.getNameLoc(), diag::err_no_member_suggest) + << Name << computeDeclContext(SS, false) << CorrectedQuotedStr + << SS.getRange(); + + // Don't try to recover; it won't work. + return true; + } + } else { + // FIXME: We found a keyword. Suggest it, but don't provide a fix-it + // because we aren't able to recover. + if (SS.isEmpty()) + Diag(R.getNameLoc(), diagnostic_suggest) << Name << CorrectedQuotedStr; + else + Diag(R.getNameLoc(), diag::err_no_member_suggest) + << Name << computeDeclContext(SS, false) << CorrectedQuotedStr + << SS.getRange(); + return true; + } + } + R.clear(); + + // Emit a special diagnostic for failed member lookups. + // FIXME: computing the declaration context might fail here (?) + if (!SS.isEmpty()) { + Diag(R.getNameLoc(), diag::err_no_member) + << Name << computeDeclContext(SS, false) + << SS.getRange(); + return true; + } + + // Give up, we can't recover. + Diag(R.getNameLoc(), diagnostic) << Name; + return true; +} + +ExprResult Sema::ActOnIdExpression(Scope *S, + CXXScopeSpec &SS, + SourceLocation TemplateKWLoc, + UnqualifiedId &Id, + bool HasTrailingLParen, + bool IsAddressOfOperand, + CorrectionCandidateCallback *CCC) { + assert(!(IsAddressOfOperand && HasTrailingLParen) && + "cannot be direct & operand and have a trailing lparen"); + + if (SS.isInvalid()) + return ExprError(); + + TemplateArgumentListInfo TemplateArgsBuffer; + + // Decompose the UnqualifiedId into the following data. + DeclarationNameInfo NameInfo; + const TemplateArgumentListInfo *TemplateArgs; + DecomposeUnqualifiedId(Id, TemplateArgsBuffer, NameInfo, TemplateArgs); + + DeclarationName Name = NameInfo.getName(); + IdentifierInfo *II = Name.getAsIdentifierInfo(); + SourceLocation NameLoc = NameInfo.getLoc(); + + // C++ [temp.dep.expr]p3: + // An id-expression is type-dependent if it contains: + // -- an identifier that was declared with a dependent type, + // (note: handled after lookup) + // -- a template-id that is dependent, + // (note: handled in BuildTemplateIdExpr) + // -- a conversion-function-id that specifies a dependent type, + // -- a nested-name-specifier that contains a class-name that + // names a dependent type. + // Determine whether this is a member of an unknown specialization; + // we need to handle these differently. + bool DependentID = false; + if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName && + Name.getCXXNameType()->isDependentType()) { + DependentID = true; + } else if (SS.isSet()) { + if (DeclContext *DC = computeDeclContext(SS, false)) { + if (RequireCompleteDeclContext(SS, DC)) + return ExprError(); + } else { + DependentID = true; + } + } + + if (DependentID) + return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, + IsAddressOfOperand, TemplateArgs); + + // Perform the required lookup. + LookupResult R(*this, NameInfo, + (Id.getKind() == UnqualifiedId::IK_ImplicitSelfParam) + ? LookupObjCImplicitSelfParam : LookupOrdinaryName); + if (TemplateArgs) { + // Lookup the template name again to correctly establish the context in + // which it was found. This is really unfortunate as we already did the + // lookup to determine that it was a template name in the first place. If + // this becomes a performance hit, we can work harder to preserve those + // results until we get here but it's likely not worth it. + bool MemberOfUnknownSpecialization; + LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false, + MemberOfUnknownSpecialization); + + if (MemberOfUnknownSpecialization || + (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)) + return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, + IsAddressOfOperand, TemplateArgs); + } else { + bool IvarLookupFollowUp = II && !SS.isSet() && getCurMethodDecl(); + LookupParsedName(R, S, &SS, !IvarLookupFollowUp); + + // If the result might be in a dependent base class, this is a dependent + // id-expression. + if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation) + return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, + IsAddressOfOperand, TemplateArgs); + + // If this reference is in an Objective-C method, then we need to do + // some special Objective-C lookup, too. + if (IvarLookupFollowUp) { + ExprResult E(LookupInObjCMethod(R, S, II, true)); + if (E.isInvalid()) + return ExprError(); + + if (Expr *Ex = E.takeAs<Expr>()) + return Owned(Ex); + } + } + + if (R.isAmbiguous()) + return ExprError(); + + // Determine whether this name might be a candidate for + // argument-dependent lookup. + bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); + + if (R.empty() && !ADL) { + // Otherwise, this could be an implicitly declared function reference (legal + // in C90, extension in C99, forbidden in C++). + if (HasTrailingLParen && II && !getLangOpts().CPlusPlus) { + NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); + if (D) R.addDecl(D); + } + + // If this name wasn't predeclared and if this is not a function + // call, diagnose the problem. + if (R.empty()) { + + // In Microsoft mode, if we are inside a template class member function + // and we can't resolve an identifier then assume the identifier is type + // dependent. The goal is to postpone name lookup to instantiation time + // to be able to search into type dependent base classes. + if (getLangOpts().MicrosoftMode && CurContext->isDependentContext() && + isa<CXXMethodDecl>(CurContext)) + return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, + IsAddressOfOperand, TemplateArgs); + + CorrectionCandidateCallback DefaultValidator; + if (DiagnoseEmptyLookup(S, SS, R, CCC ? *CCC : DefaultValidator)) + return ExprError(); + + assert(!R.empty() && + "DiagnoseEmptyLookup returned false but added no results"); + + // If we found an Objective-C instance variable, let + // LookupInObjCMethod build the appropriate expression to + // reference the ivar. + if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { + R.clear(); + ExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); + // In a hopelessly buggy code, Objective-C instance variable + // lookup fails and no expression will be built to reference it. + if (!E.isInvalid() && !E.get()) + return ExprError(); + return move(E); + } + } + } + + // This is guaranteed from this point on. + assert(!R.empty() || ADL); + + // Check whether this might be a C++ implicit instance member access. + // C++ [class.mfct.non-static]p3: + // When an id-expression that is not part of a class member access + // syntax and not used to form a pointer to member is used in the + // body of a non-static member function of class X, if name lookup + // resolves the name in the id-expression to a non-static non-type + // member of some class C, the id-expression is transformed into a + // class member access expression using (*this) as the + // postfix-expression to the left of the . operator. + // + // But we don't actually need to do this for '&' operands if R + // resolved to a function or overloaded function set, because the + // expression is ill-formed if it actually works out to be a + // non-static member function: + // + // C++ [expr.ref]p4: + // Otherwise, if E1.E2 refers to a non-static member function. . . + // [t]he expression can be used only as the left-hand operand of a + // member function call. + // + // There are other safeguards against such uses, but it's important + // to get this right here so that we don't end up making a + // spuriously dependent expression if we're inside a dependent + // instance method. + if (!R.empty() && (*R.begin())->isCXXClassMember()) { + bool MightBeImplicitMember; + if (!IsAddressOfOperand) + MightBeImplicitMember = true; + else if (!SS.isEmpty()) + MightBeImplicitMember = false; + else if (R.isOverloadedResult()) + MightBeImplicitMember = false; + else if (R.isUnresolvableResult()) + MightBeImplicitMember = true; + else + MightBeImplicitMember = isa<FieldDecl>(R.getFoundDecl()) || + isa<IndirectFieldDecl>(R.getFoundDecl()); + + if (MightBeImplicitMember) + return BuildPossibleImplicitMemberExpr(SS, TemplateKWLoc, + R, TemplateArgs); + } + + if (TemplateArgs || TemplateKWLoc.isValid()) + return BuildTemplateIdExpr(SS, TemplateKWLoc, R, ADL, TemplateArgs); + + return BuildDeclarationNameExpr(SS, R, ADL); +} + +/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified +/// declaration name, generally during template instantiation. +/// There's a large number of things which don't need to be done along +/// this path. +ExprResult +Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS, + const DeclarationNameInfo &NameInfo) { + DeclContext *DC; + if (!(DC = computeDeclContext(SS, false)) || DC->isDependentContext()) + return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(), + NameInfo, /*TemplateArgs=*/0); + + if (RequireCompleteDeclContext(SS, DC)) + return ExprError(); + + LookupResult R(*this, NameInfo, LookupOrdinaryName); + LookupQualifiedName(R, DC); + + if (R.isAmbiguous()) + return ExprError(); + + if (R.empty()) { + Diag(NameInfo.getLoc(), diag::err_no_member) + << NameInfo.getName() << DC << SS.getRange(); + return ExprError(); + } + + return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); +} + +/// LookupInObjCMethod - The parser has read a name in, and Sema has +/// detected that we're currently inside an ObjC method. Perform some +/// additional lookup. +/// +/// Ideally, most of this would be done by lookup, but there's +/// actually quite a lot of extra work involved. +/// +/// Returns a null sentinel to indicate trivial success. +ExprResult +Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, + IdentifierInfo *II, bool AllowBuiltinCreation) { + SourceLocation Loc = Lookup.getNameLoc(); + ObjCMethodDecl *CurMethod = getCurMethodDecl(); + + // There are two cases to handle here. 1) scoped lookup could have failed, + // in which case we should look for an ivar. 2) scoped lookup could have + // found a decl, but that decl is outside the current instance method (i.e. + // a global variable). In these two cases, we do a lookup for an ivar with + // this name, if the lookup sucedes, we replace it our current decl. + + // If we're in a class method, we don't normally want to look for + // ivars. But if we don't find anything else, and there's an + // ivar, that's an error. + bool IsClassMethod = CurMethod->isClassMethod(); + + bool LookForIvars; + if (Lookup.empty()) + LookForIvars = true; + else if (IsClassMethod) + LookForIvars = false; + else + LookForIvars = (Lookup.isSingleResult() && + Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); + ObjCInterfaceDecl *IFace = 0; + if (LookForIvars) { + IFace = CurMethod->getClassInterface(); + ObjCInterfaceDecl *ClassDeclared; + ObjCIvarDecl *IV = 0; + if (IFace && (IV = IFace->lookupInstanceVariable(II, ClassDeclared))) { + // Diagnose using an ivar in a class method. + if (IsClassMethod) + return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) + << IV->getDeclName()); + + // If we're referencing an invalid decl, just return this as a silent + // error node. The error diagnostic was already emitted on the decl. + if (IV->isInvalidDecl()) + return ExprError(); + + // Check if referencing a field with __attribute__((deprecated)). + if (DiagnoseUseOfDecl(IV, Loc)) + return ExprError(); + + // Diagnose the use of an ivar outside of the declaring class. + if (IV->getAccessControl() == ObjCIvarDecl::Private && + !declaresSameEntity(ClassDeclared, IFace) && + !getLangOpts().DebuggerSupport) + Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); + + // FIXME: This should use a new expr for a direct reference, don't + // turn this into Self->ivar, just return a BareIVarExpr or something. + IdentifierInfo &II = Context.Idents.get("self"); + UnqualifiedId SelfName; + SelfName.setIdentifier(&II, SourceLocation()); + SelfName.setKind(UnqualifiedId::IK_ImplicitSelfParam); + CXXScopeSpec SelfScopeSpec; + SourceLocation TemplateKWLoc; + ExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, TemplateKWLoc, + SelfName, false, false); + if (SelfExpr.isInvalid()) + return ExprError(); + + SelfExpr = DefaultLvalueConversion(SelfExpr.take()); + if (SelfExpr.isInvalid()) + return ExprError(); + + MarkAnyDeclReferenced(Loc, IV); + return Owned(new (Context) + ObjCIvarRefExpr(IV, IV->getType(), Loc, + SelfExpr.take(), true, true)); + } + } else if (CurMethod->isInstanceMethod()) { + // We should warn if a local variable hides an ivar. + if (ObjCInterfaceDecl *IFace = CurMethod->getClassInterface()) { + ObjCInterfaceDecl *ClassDeclared; + if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { + if (IV->getAccessControl() != ObjCIvarDecl::Private || + declaresSameEntity(IFace, ClassDeclared)) + Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); + } + } + } else if (Lookup.isSingleResult() && + Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()) { + // If accessing a stand-alone ivar in a class method, this is an error. + if (const ObjCIvarDecl *IV = dyn_cast<ObjCIvarDecl>(Lookup.getFoundDecl())) + return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) + << IV->getDeclName()); + } + + if (Lookup.empty() && II && AllowBuiltinCreation) { + // FIXME. Consolidate this with similar code in LookupName. + if (unsigned BuiltinID = II->getBuiltinID()) { + if (!(getLangOpts().CPlusPlus && + Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { + NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, + S, Lookup.isForRedeclaration(), + Lookup.getNameLoc()); + if (D) Lookup.addDecl(D); + } + } + } + // Sentinel value saying that we didn't do anything special. + return Owned((Expr*) 0); +} + +/// \brief Cast a base object to a member's actual type. +/// +/// Logically this happens in three phases: +/// +/// * First we cast from the base type to the naming class. +/// The naming class is the class into which we were looking +/// when we found the member; it's the qualifier type if a +/// qualifier was provided, and otherwise it's the base type. +/// +/// * Next we cast from the naming class to the declaring class. +/// If the member we found was brought into a class's scope by +/// a using declaration, this is that class; otherwise it's +/// the class declaring the member. +/// +/// * Finally we cast from the declaring class to the "true" +/// declaring class of the member. This conversion does not +/// obey access control. +ExprResult +Sema::PerformObjectMemberConversion(Expr *From, + NestedNameSpecifier *Qualifier, + NamedDecl *FoundDecl, + NamedDecl *Member) { + CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); + if (!RD) + return Owned(From); + + QualType DestRecordType; + QualType DestType; + QualType FromRecordType; + QualType FromType = From->getType(); + bool PointerConversions = false; + if (isa<FieldDecl>(Member)) { + DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); + + if (FromType->getAs<PointerType>()) { + DestType = Context.getPointerType(DestRecordType); + FromRecordType = FromType->getPointeeType(); + PointerConversions = true; + } else { + DestType = DestRecordType; + FromRecordType = FromType; + } + } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { + if (Method->isStatic()) + return Owned(From); + + DestType = Method->getThisType(Context); + DestRecordType = DestType->getPointeeType(); + + if (FromType->getAs<PointerType>()) { + FromRecordType = FromType->getPointeeType(); + PointerConversions = true; + } else { + FromRecordType = FromType; + DestType = DestRecordType; + } + } else { + // No conversion necessary. + return Owned(From); + } + + if (DestType->isDependentType() || FromType->isDependentType()) + return Owned(From); + + // If the unqualified types are the same, no conversion is necessary. + if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) + return Owned(From); + + SourceRange FromRange = From->getSourceRange(); + SourceLocation FromLoc = FromRange.getBegin(); + + ExprValueKind VK = From->getValueKind(); + + // C++ [class.member.lookup]p8: + // [...] Ambiguities can often be resolved by qualifying a name with its + // class name. + // + // If the member was a qualified name and the qualified referred to a + // specific base subobject type, we'll cast to that intermediate type + // first and then to the object in which the member is declared. That allows + // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: + // + // class Base { public: int x; }; + // class Derived1 : public Base { }; + // class Derived2 : public Base { }; + // class VeryDerived : public Derived1, public Derived2 { void f(); }; + // + // void VeryDerived::f() { + // x = 17; // error: ambiguous base subobjects + // Derived1::x = 17; // okay, pick the Base subobject of Derived1 + // } + if (Qualifier) { + QualType QType = QualType(Qualifier->getAsType(), 0); + assert(!QType.isNull() && "lookup done with dependent qualifier?"); + assert(QType->isRecordType() && "lookup done with non-record type"); + + QualType QRecordType = QualType(QType->getAs<RecordType>(), 0); + + // In C++98, the qualifier type doesn't actually have to be a base + // type of the object type, in which case we just ignore it. + // Otherwise build the appropriate casts. + if (IsDerivedFrom(FromRecordType, QRecordType)) { + CXXCastPath BasePath; + if (CheckDerivedToBaseConversion(FromRecordType, QRecordType, + FromLoc, FromRange, &BasePath)) + return ExprError(); + + if (PointerConversions) + QType = Context.getPointerType(QType); + From = ImpCastExprToType(From, QType, CK_UncheckedDerivedToBase, + VK, &BasePath).take(); + + FromType = QType; + FromRecordType = QRecordType; + + // If the qualifier type was the same as the destination type, + // we're done. + if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) + return Owned(From); + } + } + + bool IgnoreAccess = false; + + // If we actually found the member through a using declaration, cast + // down to the using declaration's type. + // + // Pointer equality is fine here because only one declaration of a + // class ever has member declarations. + if (FoundDecl->getDeclContext() != Member->getDeclContext()) { + assert(isa<UsingShadowDecl>(FoundDecl)); + QualType URecordType = Context.getTypeDeclType( + cast<CXXRecordDecl>(FoundDecl->getDeclContext())); + + // We only need to do this if the naming-class to declaring-class + // conversion is non-trivial. + if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) { + assert(IsDerivedFrom(FromRecordType, URecordType)); + CXXCastPath BasePath; + if (CheckDerivedToBaseConversion(FromRecordType, URecordType, + FromLoc, FromRange, &BasePath)) + return ExprError(); + + QualType UType = URecordType; + if (PointerConversions) + UType = Context.getPointerType(UType); + From = ImpCastExprToType(From, UType, CK_UncheckedDerivedToBase, + VK, &BasePath).take(); + FromType = UType; + FromRecordType = URecordType; + } + + // We don't do access control for the conversion from the + // declaring class to the true declaring class. + IgnoreAccess = true; + } + + CXXCastPath BasePath; + if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType, + FromLoc, FromRange, &BasePath, + IgnoreAccess)) + return ExprError(); + + return ImpCastExprToType(From, DestType, CK_UncheckedDerivedToBase, + VK, &BasePath); +} + +bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, + const LookupResult &R, + bool HasTrailingLParen) { + // Only when used directly as the postfix-expression of a call. + if (!HasTrailingLParen) + return false; + + // Never if a scope specifier was provided. + if (SS.isSet()) + return false; + + // Only in C++ or ObjC++. + if (!getLangOpts().CPlusPlus) + return false; + + // Turn off ADL when we find certain kinds of declarations during + // normal lookup: + for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { + NamedDecl *D = *I; + + // C++0x [basic.lookup.argdep]p3: + // -- a declaration of a class member + // Since using decls preserve this property, we check this on the + // original decl. + if (D->isCXXClassMember()) + return false; + + // C++0x [basic.lookup.argdep]p3: + // -- a block-scope function declaration that is not a + // using-declaration + // NOTE: we also trigger this for function templates (in fact, we + // don't check the decl type at all, since all other decl types + // turn off ADL anyway). + if (isa<UsingShadowDecl>(D)) + D = cast<UsingShadowDecl>(D)->getTargetDecl(); + else if (D->getDeclContext()->isFunctionOrMethod()) + return false; + + // C++0x [basic.lookup.argdep]p3: + // -- a declaration that is neither a function or a function + // template + // And also for builtin functions. + if (isa<FunctionDecl>(D)) { + FunctionDecl *FDecl = cast<FunctionDecl>(D); + + // But also builtin functions. + if (FDecl->getBuiltinID() && FDecl->isImplicit()) + return false; + } else if (!isa<FunctionTemplateDecl>(D)) + return false; + } + + return true; +} + + +/// Diagnoses obvious problems with the use of the given declaration +/// as an expression. This is only actually called for lookups that +/// were not overloaded, and it doesn't promise that the declaration +/// will in fact be used. +static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { + if (isa<TypedefNameDecl>(D)) { + S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); + return true; + } + + if (isa<ObjCInterfaceDecl>(D)) { + S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); + return true; + } + + if (isa<NamespaceDecl>(D)) { + S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); + return true; + } + + return false; +} + +ExprResult +Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, + LookupResult &R, + bool NeedsADL) { + // If this is a single, fully-resolved result and we don't need ADL, + // just build an ordinary singleton decl ref. + if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) + return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), + R.getFoundDecl()); + + // We only need to check the declaration if there's exactly one + // result, because in the overloaded case the results can only be + // functions and function templates. + if (R.isSingleResult() && + CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) + return ExprError(); + + // Otherwise, just build an unresolved lookup expression. Suppress + // any lookup-related diagnostics; we'll hash these out later, when + // we've picked a target. + R.suppressDiagnostics(); + + UnresolvedLookupExpr *ULE + = UnresolvedLookupExpr::Create(Context, R.getNamingClass(), + SS.getWithLocInContext(Context), + R.getLookupNameInfo(), + NeedsADL, R.isOverloadedResult(), + R.begin(), R.end()); + + return Owned(ULE); +} + +/// \brief Complete semantic analysis for a reference to the given declaration. +ExprResult +Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, + const DeclarationNameInfo &NameInfo, + NamedDecl *D) { + assert(D && "Cannot refer to a NULL declaration"); + assert(!isa<FunctionTemplateDecl>(D) && + "Cannot refer unambiguously to a function template"); + + SourceLocation Loc = NameInfo.getLoc(); + if (CheckDeclInExpr(*this, Loc, D)) + return ExprError(); + + if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { + // Specifically diagnose references to class templates that are missing + // a template argument list. + Diag(Loc, diag::err_template_decl_ref) + << Template << SS.getRange(); + Diag(Template->getLocation(), diag::note_template_decl_here); + return ExprError(); + } + + // Make sure that we're referring to a value. + ValueDecl *VD = dyn_cast<ValueDecl>(D); + if (!VD) { + Diag(Loc, diag::err_ref_non_value) + << D << SS.getRange(); + Diag(D->getLocation(), diag::note_declared_at); + return ExprError(); + } + + // Check whether this declaration can be used. Note that we suppress + // this check when we're going to perform argument-dependent lookup + // on this function name, because this might not be the function + // that overload resolution actually selects. + if (DiagnoseUseOfDecl(VD, Loc)) + return ExprError(); + + // Only create DeclRefExpr's for valid Decl's. + if (VD->isInvalidDecl()) + return ExprError(); + + // Handle members of anonymous structs and unions. If we got here, + // and the reference is to a class member indirect field, then this + // must be the subject of a pointer-to-member expression. + if (IndirectFieldDecl *indirectField = dyn_cast<IndirectFieldDecl>(VD)) + if (!indirectField->isCXXClassMember()) + return BuildAnonymousStructUnionMemberReference(SS, NameInfo.getLoc(), + indirectField); + + { + QualType type = VD->getType(); + ExprValueKind valueKind = VK_RValue; + + switch (D->getKind()) { + // Ignore all the non-ValueDecl kinds. +#define ABSTRACT_DECL(kind) +#define VALUE(type, base) +#define DECL(type, base) \ + case Decl::type: +#include "clang/AST/DeclNodes.inc" + llvm_unreachable("invalid value decl kind"); + + // These shouldn't make it here. + case Decl::ObjCAtDefsField: + case Decl::ObjCIvar: + llvm_unreachable("forming non-member reference to ivar?"); + + // Enum constants are always r-values and never references. + // Unresolved using declarations are dependent. + case Decl::EnumConstant: + case Decl::UnresolvedUsingValue: + valueKind = VK_RValue; + break; + + // Fields and indirect fields that got here must be for + // pointer-to-member expressions; we just call them l-values for + // internal consistency, because this subexpression doesn't really + // exist in the high-level semantics. + case Decl::Field: + case Decl::IndirectField: + assert(getLangOpts().CPlusPlus && + "building reference to field in C?"); + + // These can't have reference type in well-formed programs, but + // for internal consistency we do this anyway. + type = type.getNonReferenceType(); + valueKind = VK_LValue; + break; + + // Non-type template parameters are either l-values or r-values + // depending on the type. + case Decl::NonTypeTemplateParm: { + if (const ReferenceType *reftype = type->getAs<ReferenceType>()) { + type = reftype->getPointeeType(); + valueKind = VK_LValue; // even if the parameter is an r-value reference + break; + } + + // For non-references, we need to strip qualifiers just in case + // the template parameter was declared as 'const int' or whatever. + valueKind = VK_RValue; + type = type.getUnqualifiedType(); + break; + } + + case Decl::Var: + // In C, "extern void blah;" is valid and is an r-value. + if (!getLangOpts().CPlusPlus && + !type.hasQualifiers() && + type->isVoidType()) { + valueKind = VK_RValue; + break; + } + // fallthrough + + case Decl::ImplicitParam: + case Decl::ParmVar: { + // These are always l-values. + valueKind = VK_LValue; + type = type.getNonReferenceType(); + + // FIXME: Does the addition of const really only apply in + // potentially-evaluated contexts? Since the variable isn't actually + // captured in an unevaluated context, it seems that the answer is no. + if (ExprEvalContexts.back().Context != Sema::Unevaluated) { + QualType CapturedType = getCapturedDeclRefType(cast<VarDecl>(VD), Loc); + if (!CapturedType.isNull()) + type = CapturedType; + } + + break; + } + + case Decl::Function: { + const FunctionType *fty = type->castAs<FunctionType>(); + + // If we're referring to a function with an __unknown_anytype + // result type, make the entire expression __unknown_anytype. + if (fty->getResultType() == Context.UnknownAnyTy) { + type = Context.UnknownAnyTy; + valueKind = VK_RValue; + break; + } + + // Functions are l-values in C++. + if (getLangOpts().CPlusPlus) { + valueKind = VK_LValue; + break; + } + + // C99 DR 316 says that, if a function type comes from a + // function definition (without a prototype), that type is only + // used for checking compatibility. Therefore, when referencing + // the function, we pretend that we don't have the full function + // type. + if (!cast<FunctionDecl>(VD)->hasPrototype() && + isa<FunctionProtoType>(fty)) + type = Context.getFunctionNoProtoType(fty->getResultType(), + fty->getExtInfo()); + + // Functions are r-values in C. + valueKind = VK_RValue; + break; + } + + case Decl::CXXMethod: + // If we're referring to a method with an __unknown_anytype + // result type, make the entire expression __unknown_anytype. + // This should only be possible with a type written directly. + if (const FunctionProtoType *proto + = dyn_cast<FunctionProtoType>(VD->getType())) + if (proto->getResultType() == Context.UnknownAnyTy) { + type = Context.UnknownAnyTy; + valueKind = VK_RValue; + break; + } + + // C++ methods are l-values if static, r-values if non-static. + if (cast<CXXMethodDecl>(VD)->isStatic()) { + valueKind = VK_LValue; + break; + } + // fallthrough + + case Decl::CXXConversion: + case Decl::CXXDestructor: + case Decl::CXXConstructor: + valueKind = VK_RValue; + break; + } + + return BuildDeclRefExpr(VD, type, valueKind, NameInfo, &SS); + } +} + +ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) { + PredefinedExpr::IdentType IT; + + switch (Kind) { + default: llvm_unreachable("Unknown simple primary expr!"); + case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] + case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; + case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; + } + + // Pre-defined identifiers are of type char[x], where x is the length of the + // string. + + Decl *currentDecl = getCurFunctionOrMethodDecl(); + if (!currentDecl && getCurBlock()) + currentDecl = getCurBlock()->TheDecl; + if (!currentDecl) { + Diag(Loc, diag::ext_predef_outside_function); + currentDecl = Context.getTranslationUnitDecl(); + } + + QualType ResTy; + if (cast<DeclContext>(currentDecl)->isDependentContext()) { + ResTy = Context.DependentTy; + } else { + unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); + + llvm::APInt LengthI(32, Length + 1); + ResTy = Context.CharTy.withConst(); + ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); + } + return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); +} + +ExprResult Sema::ActOnCharacterConstant(const Token &Tok, Scope *UDLScope) { + SmallString<16> CharBuffer; + bool Invalid = false; + StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); + if (Invalid) + return ExprError(); + + CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), + PP, Tok.getKind()); + if (Literal.hadError()) + return ExprError(); + + QualType Ty; + if (Literal.isWide()) + Ty = Context.WCharTy; // L'x' -> wchar_t in C and C++. + else if (Literal.isUTF16()) + Ty = Context.Char16Ty; // u'x' -> char16_t in C11 and C++11. + else if (Literal.isUTF32()) + Ty = Context.Char32Ty; // U'x' -> char32_t in C11 and C++11. + else if (!getLangOpts().CPlusPlus || Literal.isMultiChar()) + Ty = Context.IntTy; // 'x' -> int in C, 'wxyz' -> int in C++. + else + Ty = Context.CharTy; // 'x' -> char in C++ + + CharacterLiteral::CharacterKind Kind = CharacterLiteral::Ascii; + if (Literal.isWide()) + Kind = CharacterLiteral::Wide; + else if (Literal.isUTF16()) + Kind = CharacterLiteral::UTF16; + else if (Literal.isUTF32()) + Kind = CharacterLiteral::UTF32; + + Expr *Lit = new (Context) CharacterLiteral(Literal.getValue(), Kind, Ty, + Tok.getLocation()); + + if (Literal.getUDSuffix().empty()) + return Owned(Lit); + + // We're building a user-defined literal. + IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix()); + SourceLocation UDSuffixLoc = + getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset()); + + // Make sure we're allowed user-defined literals here. + if (!UDLScope) + return ExprError(Diag(UDSuffixLoc, diag::err_invalid_character_udl)); + + // C++11 [lex.ext]p6: The literal L is treated as a call of the form + // operator "" X (ch) + return BuildCookedLiteralOperatorCall(*this, UDLScope, UDSuffix, UDSuffixLoc, + llvm::makeArrayRef(&Lit, 1), + Tok.getLocation()); +} + +ExprResult Sema::ActOnIntegerConstant(SourceLocation Loc, uint64_t Val) { + unsigned IntSize = Context.getTargetInfo().getIntWidth(); + return Owned(IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val), + Context.IntTy, Loc)); +} + +static Expr *BuildFloatingLiteral(Sema &S, NumericLiteralParser &Literal, + QualType Ty, SourceLocation Loc) { + const llvm::fltSemantics &Format = S.Context.getFloatTypeSemantics(Ty); + + using llvm::APFloat; + APFloat Val(Format); + + APFloat::opStatus result = Literal.GetFloatValue(Val); + + // Overflow is always an error, but underflow is only an error if + // we underflowed to zero (APFloat reports denormals as underflow). + if ((result & APFloat::opOverflow) || + ((result & APFloat::opUnderflow) && Val.isZero())) { + unsigned diagnostic; + SmallString<20> buffer; + if (result & APFloat::opOverflow) { + diagnostic = diag::warn_float_overflow; + APFloat::getLargest(Format).toString(buffer); + } else { + diagnostic = diag::warn_float_underflow; + APFloat::getSmallest(Format).toString(buffer); + } + + S.Diag(Loc, diagnostic) + << Ty + << StringRef(buffer.data(), buffer.size()); + } + + bool isExact = (result == APFloat::opOK); + return FloatingLiteral::Create(S.Context, Val, isExact, Ty, Loc); +} + +ExprResult Sema::ActOnNumericConstant(const Token &Tok, Scope *UDLScope) { + // Fast path for a single digit (which is quite common). A single digit + // cannot have a trigraph, escaped newline, radix prefix, or suffix. + if (Tok.getLength() == 1) { + const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); + return ActOnIntegerConstant(Tok.getLocation(), Val-'0'); + } + + SmallString<512> IntegerBuffer; + // Add padding so that NumericLiteralParser can overread by one character. + IntegerBuffer.resize(Tok.getLength()+1); + const char *ThisTokBegin = &IntegerBuffer[0]; + + // Get the spelling of the token, which eliminates trigraphs, etc. + bool Invalid = false; + unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid); + if (Invalid) + return ExprError(); + + NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, + Tok.getLocation(), PP); + if (Literal.hadError) + return ExprError(); + + if (Literal.hasUDSuffix()) { + // We're building a user-defined literal. + IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix()); + SourceLocation UDSuffixLoc = + getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset()); + + // Make sure we're allowed user-defined literals here. + if (!UDLScope) + return ExprError(Diag(UDSuffixLoc, diag::err_invalid_numeric_udl)); + + QualType CookedTy; + if (Literal.isFloatingLiteral()) { + // C++11 [lex.ext]p4: If S contains a literal operator with parameter type + // long double, the literal is treated as a call of the form + // operator "" X (f L) + CookedTy = Context.LongDoubleTy; + } else { + // C++11 [lex.ext]p3: If S contains a literal operator with parameter type + // unsigned long long, the literal is treated as a call of the form + // operator "" X (n ULL) + CookedTy = Context.UnsignedLongLongTy; + } + + DeclarationName OpName = + Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix); + DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc); + OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc); + + // Perform literal operator lookup to determine if we're building a raw + // literal or a cooked one. + LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName); + switch (LookupLiteralOperator(UDLScope, R, llvm::makeArrayRef(&CookedTy, 1), + /*AllowRawAndTemplate*/true)) { + case LOLR_Error: + return ExprError(); + + case LOLR_Cooked: { + Expr *Lit; + if (Literal.isFloatingLiteral()) { + Lit = BuildFloatingLiteral(*this, Literal, CookedTy, Tok.getLocation()); + } else { + llvm::APInt ResultVal(Context.getTargetInfo().getLongLongWidth(), 0); + if (Literal.GetIntegerValue(ResultVal)) + Diag(Tok.getLocation(), diag::warn_integer_too_large); + Lit = IntegerLiteral::Create(Context, ResultVal, CookedTy, + Tok.getLocation()); + } + return BuildLiteralOperatorCall(R, OpNameInfo, + llvm::makeArrayRef(&Lit, 1), + Tok.getLocation()); + } + + case LOLR_Raw: { + // C++11 [lit.ext]p3, p4: If S contains a raw literal operator, the + // literal is treated as a call of the form + // operator "" X ("n") + SourceLocation TokLoc = Tok.getLocation(); + unsigned Length = Literal.getUDSuffixOffset(); + QualType StrTy = Context.getConstantArrayType( + Context.CharTy, llvm::APInt(32, Length + 1), + ArrayType::Normal, 0); + Expr *Lit = StringLiteral::Create( + Context, StringRef(ThisTokBegin, Length), StringLiteral::Ascii, + /*Pascal*/false, StrTy, &TokLoc, 1); + return BuildLiteralOperatorCall(R, OpNameInfo, + llvm::makeArrayRef(&Lit, 1), TokLoc); + } + + case LOLR_Template: + // C++11 [lit.ext]p3, p4: Otherwise (S contains a literal operator + // template), L is treated as a call fo the form + // operator "" X <'c1', 'c2', ... 'ck'>() + // where n is the source character sequence c1 c2 ... ck. + TemplateArgumentListInfo ExplicitArgs; + unsigned CharBits = Context.getIntWidth(Context.CharTy); + bool CharIsUnsigned = Context.CharTy->isUnsignedIntegerType(); + llvm::APSInt Value(CharBits, CharIsUnsigned); + for (unsigned I = 0, N = Literal.getUDSuffixOffset(); I != N; ++I) { + Value = ThisTokBegin[I]; + TemplateArgument Arg(Value, Context.CharTy); + TemplateArgumentLocInfo ArgInfo; + ExplicitArgs.addArgument(TemplateArgumentLoc(Arg, ArgInfo)); + } + return BuildLiteralOperatorCall(R, OpNameInfo, ArrayRef<Expr*>(), + Tok.getLocation(), &ExplicitArgs); + } + + llvm_unreachable("unexpected literal operator lookup result"); + } + + Expr *Res; + + if (Literal.isFloatingLiteral()) { + QualType Ty; + if (Literal.isFloat) + Ty = Context.FloatTy; + else if (!Literal.isLong) + Ty = Context.DoubleTy; + else + Ty = Context.LongDoubleTy; + + Res = BuildFloatingLiteral(*this, Literal, Ty, Tok.getLocation()); + + if (Ty == Context.DoubleTy) { + if (getLangOpts().SinglePrecisionConstants) { + Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); + } else if (getLangOpts().OpenCL && !getOpenCLOptions().cl_khr_fp64) { + Diag(Tok.getLocation(), diag::warn_double_const_requires_fp64); + Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); + } + } + } else if (!Literal.isIntegerLiteral()) { + return ExprError(); + } else { + QualType Ty; + + // long long is a C99 feature. + if (!getLangOpts().C99 && Literal.isLongLong) + Diag(Tok.getLocation(), + getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_longlong : diag::ext_longlong); + + // Get the value in the widest-possible width. + llvm::APInt ResultVal(Context.getTargetInfo().getIntMaxTWidth(), 0); + + if (Literal.GetIntegerValue(ResultVal)) { + // If this value didn't fit into uintmax_t, warn and force to ull. + Diag(Tok.getLocation(), diag::warn_integer_too_large); + Ty = Context.UnsignedLongLongTy; + assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && + "long long is not intmax_t?"); + } else { + // If this value fits into a ULL, try to figure out what else it fits into + // according to the rules of C99 6.4.4.1p5. + + // Octal, Hexadecimal, and integers with a U suffix are allowed to + // be an unsigned int. + bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; + + // Check from smallest to largest, picking the smallest type we can. + unsigned Width = 0; + if (!Literal.isLong && !Literal.isLongLong) { + // Are int/unsigned possibilities? + unsigned IntSize = Context.getTargetInfo().getIntWidth(); + + // Does it fit in a unsigned int? + if (ResultVal.isIntN(IntSize)) { + // Does it fit in a signed int? + if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) + Ty = Context.IntTy; + else if (AllowUnsigned) + Ty = Context.UnsignedIntTy; + Width = IntSize; + } + } + + // Are long/unsigned long possibilities? + if (Ty.isNull() && !Literal.isLongLong) { + unsigned LongSize = Context.getTargetInfo().getLongWidth(); + + // Does it fit in a unsigned long? + if (ResultVal.isIntN(LongSize)) { + // Does it fit in a signed long? + if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) + Ty = Context.LongTy; + else if (AllowUnsigned) + Ty = Context.UnsignedLongTy; + Width = LongSize; + } + } + + // Finally, check long long if needed. + if (Ty.isNull()) { + unsigned LongLongSize = Context.getTargetInfo().getLongLongWidth(); + + // Does it fit in a unsigned long long? + if (ResultVal.isIntN(LongLongSize)) { + // Does it fit in a signed long long? + // To be compatible with MSVC, hex integer literals ending with the + // LL or i64 suffix are always signed in Microsoft mode. + if (!Literal.isUnsigned && (ResultVal[LongLongSize-1] == 0 || + (getLangOpts().MicrosoftExt && Literal.isLongLong))) + Ty = Context.LongLongTy; + else if (AllowUnsigned) + Ty = Context.UnsignedLongLongTy; + Width = LongLongSize; + } + } + + // If we still couldn't decide a type, we probably have something that + // does not fit in a signed long long, but has no U suffix. + if (Ty.isNull()) { + Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); + Ty = Context.UnsignedLongLongTy; + Width = Context.getTargetInfo().getLongLongWidth(); + } + + if (ResultVal.getBitWidth() != Width) + ResultVal = ResultVal.trunc(Width); + } + Res = IntegerLiteral::Create(Context, ResultVal, Ty, Tok.getLocation()); + } + + // If this is an imaginary literal, create the ImaginaryLiteral wrapper. + if (Literal.isImaginary) + Res = new (Context) ImaginaryLiteral(Res, + Context.getComplexType(Res->getType())); + + return Owned(Res); +} + +ExprResult Sema::ActOnParenExpr(SourceLocation L, SourceLocation R, Expr *E) { + assert((E != 0) && "ActOnParenExpr() missing expr"); + return Owned(new (Context) ParenExpr(L, R, E)); +} + +static bool CheckVecStepTraitOperandType(Sema &S, QualType T, + SourceLocation Loc, + SourceRange ArgRange) { + // [OpenCL 1.1 6.11.12] "The vec_step built-in function takes a built-in + // scalar or vector data type argument..." + // Every built-in scalar type (OpenCL 1.1 6.1.1) is either an arithmetic + // type (C99 6.2.5p18) or void. + if (!(T->isArithmeticType() || T->isVoidType() || T->isVectorType())) { + S.Diag(Loc, diag::err_vecstep_non_scalar_vector_type) + << T << ArgRange; + return true; + } + + assert((T->isVoidType() || !T->isIncompleteType()) && + "Scalar types should always be complete"); + return false; +} + +static bool CheckExtensionTraitOperandType(Sema &S, QualType T, + SourceLocation Loc, + SourceRange ArgRange, + UnaryExprOrTypeTrait TraitKind) { + // C99 6.5.3.4p1: + if (T->isFunctionType()) { + // alignof(function) is allowed as an extension. + if (TraitKind == UETT_SizeOf) + S.Diag(Loc, diag::ext_sizeof_function_type) << ArgRange; + return false; + } + + // Allow sizeof(void)/alignof(void) as an extension. + if (T->isVoidType()) { + S.Diag(Loc, diag::ext_sizeof_void_type) << TraitKind << ArgRange; + return false; + } + + return true; +} + +static bool CheckObjCTraitOperandConstraints(Sema &S, QualType T, + SourceLocation Loc, + SourceRange ArgRange, + UnaryExprOrTypeTrait TraitKind) { + // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. + if (S.LangOpts.ObjCNonFragileABI && T->isObjCObjectType()) { + S.Diag(Loc, diag::err_sizeof_nonfragile_interface) + << T << (TraitKind == UETT_SizeOf) + << ArgRange; + return true; + } + + return false; +} + +/// \brief Check the constrains on expression operands to unary type expression +/// and type traits. +/// +/// Completes any types necessary and validates the constraints on the operand +/// expression. The logic mostly mirrors the type-based overload, but may modify +/// the expression as it completes the type for that expression through template +/// instantiation, etc. +bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E, + UnaryExprOrTypeTrait ExprKind) { + QualType ExprTy = E->getType(); + + // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, + // the result is the size of the referenced type." + // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the + // result shall be the alignment of the referenced type." + if (const ReferenceType *Ref = ExprTy->getAs<ReferenceType>()) + ExprTy = Ref->getPointeeType(); + + if (ExprKind == UETT_VecStep) + return CheckVecStepTraitOperandType(*this, ExprTy, E->getExprLoc(), + E->getSourceRange()); + + // Whitelist some types as extensions + if (!CheckExtensionTraitOperandType(*this, ExprTy, E->getExprLoc(), + E->getSourceRange(), ExprKind)) + return false; + + if (RequireCompleteExprType(E, + PDiag(diag::err_sizeof_alignof_incomplete_type) + << ExprKind << E->getSourceRange(), + std::make_pair(SourceLocation(), PDiag(0)))) + return true; + + // Completeing the expression's type may have changed it. + ExprTy = E->getType(); + if (const ReferenceType *Ref = ExprTy->getAs<ReferenceType>()) + ExprTy = Ref->getPointeeType(); + + if (CheckObjCTraitOperandConstraints(*this, ExprTy, E->getExprLoc(), + E->getSourceRange(), ExprKind)) + return true; + + if (ExprKind == UETT_SizeOf) { + if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParens())) { + if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DeclRef->getFoundDecl())) { + QualType OType = PVD->getOriginalType(); + QualType Type = PVD->getType(); + if (Type->isPointerType() && OType->isArrayType()) { + Diag(E->getExprLoc(), diag::warn_sizeof_array_param) + << Type << OType; + Diag(PVD->getLocation(), diag::note_declared_at); + } + } + } + } + + return false; +} + +/// \brief Check the constraints on operands to unary expression and type +/// traits. +/// +/// This will complete any types necessary, and validate the various constraints +/// on those operands. +/// +/// The UsualUnaryConversions() function is *not* called by this routine. +/// C99 6.3.2.1p[2-4] all state: +/// Except when it is the operand of the sizeof operator ... +/// +/// C++ [expr.sizeof]p4 +/// The lvalue-to-rvalue, array-to-pointer, and function-to-pointer +/// standard conversions are not applied to the operand of sizeof. +/// +/// This policy is followed for all of the unary trait expressions. +bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType ExprType, + SourceLocation OpLoc, + SourceRange ExprRange, + UnaryExprOrTypeTrait ExprKind) { + if (ExprType->isDependentType()) + return false; + + // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, + // the result is the size of the referenced type." + // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the + // result shall be the alignment of the referenced type." + if (const ReferenceType *Ref = ExprType->getAs<ReferenceType>()) + ExprType = Ref->getPointeeType(); + + if (ExprKind == UETT_VecStep) + return CheckVecStepTraitOperandType(*this, ExprType, OpLoc, ExprRange); + + // Whitelist some types as extensions + if (!CheckExtensionTraitOperandType(*this, ExprType, OpLoc, ExprRange, + ExprKind)) + return false; + + if (RequireCompleteType(OpLoc, ExprType, + PDiag(diag::err_sizeof_alignof_incomplete_type) + << ExprKind << ExprRange)) + return true; + + if (CheckObjCTraitOperandConstraints(*this, ExprType, OpLoc, ExprRange, + ExprKind)) + return true; + + return false; +} + +static bool CheckAlignOfExpr(Sema &S, Expr *E) { + E = E->IgnoreParens(); + + // alignof decl is always ok. + if (isa<DeclRefExpr>(E)) + return false; + + // Cannot know anything else if the expression is dependent. + if (E->isTypeDependent()) + return false; + + if (E->getBitField()) { + S.Diag(E->getExprLoc(), diag::err_sizeof_alignof_bitfield) + << 1 << E->getSourceRange(); + return true; + } + + // Alignment of a field access is always okay, so long as it isn't a + // bit-field. + if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) + if (isa<FieldDecl>(ME->getMemberDecl())) + return false; + + return S.CheckUnaryExprOrTypeTraitOperand(E, UETT_AlignOf); +} + +bool Sema::CheckVecStepExpr(Expr *E) { + E = E->IgnoreParens(); + + // Cannot know anything else if the expression is dependent. + if (E->isTypeDependent()) + return false; + + return CheckUnaryExprOrTypeTraitOperand(E, UETT_VecStep); +} + +/// \brief Build a sizeof or alignof expression given a type operand. +ExprResult +Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo, + SourceLocation OpLoc, + UnaryExprOrTypeTrait ExprKind, + SourceRange R) { + if (!TInfo) + return ExprError(); + + QualType T = TInfo->getType(); + + if (!T->isDependentType() && + CheckUnaryExprOrTypeTraitOperand(T, OpLoc, R, ExprKind)) + return ExprError(); + + // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. + return Owned(new (Context) UnaryExprOrTypeTraitExpr(ExprKind, TInfo, + Context.getSizeType(), + OpLoc, R.getEnd())); +} + +/// \brief Build a sizeof or alignof expression given an expression +/// operand. +ExprResult +Sema::CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc, + UnaryExprOrTypeTrait ExprKind) { + ExprResult PE = CheckPlaceholderExpr(E); + if (PE.isInvalid()) + return ExprError(); + + E = PE.get(); + + // Verify that the operand is valid. + bool isInvalid = false; + if (E->isTypeDependent()) { + // Delay type-checking for type-dependent expressions. + } else if (ExprKind == UETT_AlignOf) { + isInvalid = CheckAlignOfExpr(*this, E); + } else if (ExprKind == UETT_VecStep) { + isInvalid = CheckVecStepExpr(E); + } else if (E->getBitField()) { // C99 6.5.3.4p1. + Diag(E->getExprLoc(), diag::err_sizeof_alignof_bitfield) << 0; + isInvalid = true; + } else { + isInvalid = CheckUnaryExprOrTypeTraitOperand(E, UETT_SizeOf); + } + + if (isInvalid) + return ExprError(); + + if (ExprKind == UETT_SizeOf && E->getType()->isVariableArrayType()) { + PE = TranformToPotentiallyEvaluated(E); + if (PE.isInvalid()) return ExprError(); + E = PE.take(); + } + + // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. + return Owned(new (Context) UnaryExprOrTypeTraitExpr( + ExprKind, E, Context.getSizeType(), OpLoc, + E->getSourceRange().getEnd())); +} + +/// ActOnUnaryExprOrTypeTraitExpr - Handle @c sizeof(type) and @c sizeof @c +/// expr and the same for @c alignof and @c __alignof +/// Note that the ArgRange is invalid if isType is false. +ExprResult +Sema::ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc, + UnaryExprOrTypeTrait ExprKind, bool IsType, + void *TyOrEx, const SourceRange &ArgRange) { + // If error parsing type, ignore. + if (TyOrEx == 0) return ExprError(); + + if (IsType) { + TypeSourceInfo *TInfo; + (void) GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrEx), &TInfo); + return CreateUnaryExprOrTypeTraitExpr(TInfo, OpLoc, ExprKind, ArgRange); + } + + Expr *ArgEx = (Expr *)TyOrEx; + ExprResult Result = CreateUnaryExprOrTypeTraitExpr(ArgEx, OpLoc, ExprKind); + return move(Result); +} + +static QualType CheckRealImagOperand(Sema &S, ExprResult &V, SourceLocation Loc, + bool IsReal) { + if (V.get()->isTypeDependent()) + return S.Context.DependentTy; + + // _Real and _Imag are only l-values for normal l-values. + if (V.get()->getObjectKind() != OK_Ordinary) { + V = S.DefaultLvalueConversion(V.take()); + if (V.isInvalid()) + return QualType(); + } + + // These operators return the element type of a complex type. + if (const ComplexType *CT = V.get()->getType()->getAs<ComplexType>()) + return CT->getElementType(); + + // Otherwise they pass through real integer and floating point types here. + if (V.get()->getType()->isArithmeticType()) + return V.get()->getType(); + + // Test for placeholders. + ExprResult PR = S.CheckPlaceholderExpr(V.get()); + if (PR.isInvalid()) return QualType(); + if (PR.get() != V.get()) { + V = move(PR); + return CheckRealImagOperand(S, V, Loc, IsReal); + } + + // Reject anything else. + S.Diag(Loc, diag::err_realimag_invalid_type) << V.get()->getType() + << (IsReal ? "__real" : "__imag"); + return QualType(); +} + + + +ExprResult +Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, + tok::TokenKind Kind, Expr *Input) { + UnaryOperatorKind Opc; + switch (Kind) { + default: llvm_unreachable("Unknown unary op!"); + case tok::plusplus: Opc = UO_PostInc; break; + case tok::minusminus: Opc = UO_PostDec; break; + } + + // Since this might is a postfix expression, get rid of ParenListExprs. + ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Input); + if (Result.isInvalid()) return ExprError(); + Input = Result.take(); + + return BuildUnaryOp(S, OpLoc, Opc, Input); +} + +ExprResult +Sema::ActOnArraySubscriptExpr(Scope *S, Expr *Base, SourceLocation LLoc, + Expr *Idx, SourceLocation RLoc) { + // Since this might be a postfix expression, get rid of ParenListExprs. + ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); + if (Result.isInvalid()) return ExprError(); + Base = Result.take(); + + Expr *LHSExp = Base, *RHSExp = Idx; + + if (getLangOpts().CPlusPlus && + (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { + return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, + Context.DependentTy, + VK_LValue, OK_Ordinary, + RLoc)); + } + + if (getLangOpts().CPlusPlus && + (LHSExp->getType()->isRecordType() || + LHSExp->getType()->isEnumeralType() || + RHSExp->getType()->isRecordType() || + RHSExp->getType()->isEnumeralType()) && + !LHSExp->getType()->isObjCObjectPointerType()) { + return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, Base, Idx); + } + + return CreateBuiltinArraySubscriptExpr(Base, LLoc, Idx, RLoc); +} + + +ExprResult +Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc, + Expr *Idx, SourceLocation RLoc) { + Expr *LHSExp = Base; + Expr *RHSExp = Idx; + + // Perform default conversions. + if (!LHSExp->getType()->getAs<VectorType>()) { + ExprResult Result = DefaultFunctionArrayLvalueConversion(LHSExp); + if (Result.isInvalid()) + return ExprError(); + LHSExp = Result.take(); + } + ExprResult Result = DefaultFunctionArrayLvalueConversion(RHSExp); + if (Result.isInvalid()) + return ExprError(); + RHSExp = Result.take(); + + QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); + ExprValueKind VK = VK_LValue; + ExprObjectKind OK = OK_Ordinary; + + // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent + // to the expression *((e1)+(e2)). This means the array "Base" may actually be + // in the subscript position. As a result, we need to derive the array base + // and index from the expression types. + Expr *BaseExpr, *IndexExpr; + QualType ResultType; + if (LHSTy->isDependentType() || RHSTy->isDependentType()) { + BaseExpr = LHSExp; + IndexExpr = RHSExp; + ResultType = Context.DependentTy; + } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { + BaseExpr = LHSExp; + IndexExpr = RHSExp; + ResultType = PTy->getPointeeType(); + } else if (const ObjCObjectPointerType *PTy = + LHSTy->getAs<ObjCObjectPointerType>()) { + BaseExpr = LHSExp; + IndexExpr = RHSExp; + Result = BuildObjCSubscriptExpression(RLoc, BaseExpr, IndexExpr, 0, 0); + if (!Result.isInvalid()) + return Owned(Result.take()); + ResultType = PTy->getPointeeType(); + } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { + // Handle the uncommon case of "123[Ptr]". + BaseExpr = RHSExp; + IndexExpr = LHSExp; + ResultType = PTy->getPointeeType(); + } else if (const ObjCObjectPointerType *PTy = + RHSTy->getAs<ObjCObjectPointerType>()) { + // Handle the uncommon case of "123[Ptr]". + BaseExpr = RHSExp; + IndexExpr = LHSExp; + ResultType = PTy->getPointeeType(); + } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { + BaseExpr = LHSExp; // vectors: V[123] + IndexExpr = RHSExp; + VK = LHSExp->getValueKind(); + if (VK != VK_RValue) + OK = OK_VectorComponent; + + // FIXME: need to deal with const... + ResultType = VTy->getElementType(); + } else if (LHSTy->isArrayType()) { + // If we see an array that wasn't promoted by + // DefaultFunctionArrayLvalueConversion, it must be an array that + // wasn't promoted because of the C90 rule that doesn't + // allow promoting non-lvalue arrays. Warn, then + // force the promotion here. + Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << + LHSExp->getSourceRange(); + LHSExp = ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), + CK_ArrayToPointerDecay).take(); + LHSTy = LHSExp->getType(); + + BaseExpr = LHSExp; + IndexExpr = RHSExp; + ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); + } else if (RHSTy->isArrayType()) { + // Same as previous, except for 123[f().a] case + Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << + RHSExp->getSourceRange(); + RHSExp = ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), + CK_ArrayToPointerDecay).take(); + RHSTy = RHSExp->getType(); + + BaseExpr = RHSExp; + IndexExpr = LHSExp; + ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); + } else { + return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) + << LHSExp->getSourceRange() << RHSExp->getSourceRange()); + } + // C99 6.5.2.1p1 + if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent()) + return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) + << IndexExpr->getSourceRange()); + + if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || + IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) + && !IndexExpr->isTypeDependent()) + Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); + + // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, + // C++ [expr.sub]p1: The type "T" shall be a completely-defined object + // type. Note that Functions are not objects, and that (in C99 parlance) + // incomplete types are not object types. + if (ResultType->isFunctionType()) { + Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) + << ResultType << BaseExpr->getSourceRange(); + return ExprError(); + } + + if (ResultType->isVoidType() && !getLangOpts().CPlusPlus) { + // GNU extension: subscripting on pointer to void + Diag(LLoc, diag::ext_gnu_subscript_void_type) + << BaseExpr->getSourceRange(); + + // C forbids expressions of unqualified void type from being l-values. + // See IsCForbiddenLValueType. + if (!ResultType.hasQualifiers()) VK = VK_RValue; + } else if (!ResultType->isDependentType() && + RequireCompleteType(LLoc, ResultType, + PDiag(diag::err_subscript_incomplete_type) + << BaseExpr->getSourceRange())) + return ExprError(); + + // Diagnose bad cases where we step over interface counts. + if (ResultType->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { + Diag(LLoc, diag::err_subscript_nonfragile_interface) + << ResultType << BaseExpr->getSourceRange(); + return ExprError(); + } + + assert(VK == VK_RValue || LangOpts.CPlusPlus || + !ResultType.isCForbiddenLValueType()); + + return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, + ResultType, VK, OK, RLoc)); +} + +ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, + FunctionDecl *FD, + ParmVarDecl *Param) { + if (Param->hasUnparsedDefaultArg()) { + Diag(CallLoc, + diag::err_use_of_default_argument_to_function_declared_later) << + FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); + Diag(UnparsedDefaultArgLocs[Param], + diag::note_default_argument_declared_here); + return ExprError(); + } + + if (Param->hasUninstantiatedDefaultArg()) { + Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); + + // Instantiate the expression. + MultiLevelTemplateArgumentList ArgList + = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); + + std::pair<const TemplateArgument *, unsigned> Innermost + = ArgList.getInnermost(); + InstantiatingTemplate Inst(*this, CallLoc, Param, Innermost.first, + Innermost.second); + + ExprResult Result; + { + // C++ [dcl.fct.default]p5: + // The names in the [default argument] expression are bound, and + // the semantic constraints are checked, at the point where the + // default argument expression appears. + ContextRAII SavedContext(*this, FD); + LocalInstantiationScope Local(*this); + Result = SubstExpr(UninstExpr, ArgList); + } + if (Result.isInvalid()) + return ExprError(); + + // Check the expression as an initializer for the parameter. + InitializedEntity Entity + = InitializedEntity::InitializeParameter(Context, Param); + InitializationKind Kind + = InitializationKind::CreateCopy(Param->getLocation(), + /*FIXME:EqualLoc*/UninstExpr->getLocStart()); + Expr *ResultE = Result.takeAs<Expr>(); + + InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); + Result = InitSeq.Perform(*this, Entity, Kind, + MultiExprArg(*this, &ResultE, 1)); + if (Result.isInvalid()) + return ExprError(); + + // Build the default argument expression. + return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, + Result.takeAs<Expr>())); + } + + // If the default expression creates temporaries, we need to + // push them to the current stack of expression temporaries so they'll + // be properly destroyed. + // FIXME: We should really be rebuilding the default argument with new + // bound temporaries; see the comment in PR5810. + // We don't need to do that with block decls, though, because + // blocks in default argument expression can never capture anything. + if (isa<ExprWithCleanups>(Param->getInit())) { + // Set the "needs cleanups" bit regardless of whether there are + // any explicit objects. + ExprNeedsCleanups = true; + + // Append all the objects to the cleanup list. Right now, this + // should always be a no-op, because blocks in default argument + // expressions should never be able to capture anything. + assert(!cast<ExprWithCleanups>(Param->getInit())->getNumObjects() && + "default argument expression has capturing blocks?"); + } + + // We already type-checked the argument, so we know it works. + // Just mark all of the declarations in this potentially-evaluated expression + // as being "referenced". + MarkDeclarationsReferencedInExpr(Param->getDefaultArg(), + /*SkipLocalVariables=*/true); + return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); +} + +/// ConvertArgumentsForCall - Converts the arguments specified in +/// Args/NumArgs to the parameter types of the function FDecl with +/// function prototype Proto. Call is the call expression itself, and +/// Fn is the function expression. For a C++ member function, this +/// routine does not attempt to convert the object argument. Returns +/// true if the call is ill-formed. +bool +Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, + FunctionDecl *FDecl, + const FunctionProtoType *Proto, + Expr **Args, unsigned NumArgs, + SourceLocation RParenLoc, + bool IsExecConfig) { + // Bail out early if calling a builtin with custom typechecking. + // We don't need to do this in the + if (FDecl) + if (unsigned ID = FDecl->getBuiltinID()) + if (Context.BuiltinInfo.hasCustomTypechecking(ID)) + return false; + + // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by + // assignment, to the types of the corresponding parameter, ... + unsigned NumArgsInProto = Proto->getNumArgs(); + bool Invalid = false; + unsigned MinArgs = FDecl ? FDecl->getMinRequiredArguments() : NumArgsInProto; + unsigned FnKind = Fn->getType()->isBlockPointerType() + ? 1 /* block */ + : (IsExecConfig ? 3 /* kernel function (exec config) */ + : 0 /* function */); + + // If too few arguments are available (and we don't have default + // arguments for the remaining parameters), don't make the call. + if (NumArgs < NumArgsInProto) { + if (NumArgs < MinArgs) { + Diag(RParenLoc, MinArgs == NumArgsInProto + ? diag::err_typecheck_call_too_few_args + : diag::err_typecheck_call_too_few_args_at_least) + << FnKind + << MinArgs << NumArgs << Fn->getSourceRange(); + + // Emit the location of the prototype. + if (FDecl && !FDecl->getBuiltinID() && !IsExecConfig) + Diag(FDecl->getLocStart(), diag::note_callee_decl) + << FDecl; + + return true; + } + Call->setNumArgs(Context, NumArgsInProto); + } + + // If too many are passed and not variadic, error on the extras and drop + // them. + if (NumArgs > NumArgsInProto) { + if (!Proto->isVariadic()) { + Diag(Args[NumArgsInProto]->getLocStart(), + MinArgs == NumArgsInProto + ? diag::err_typecheck_call_too_many_args + : diag::err_typecheck_call_too_many_args_at_most) + << FnKind + << NumArgsInProto << NumArgs << Fn->getSourceRange() + << SourceRange(Args[NumArgsInProto]->getLocStart(), + Args[NumArgs-1]->getLocEnd()); + + // Emit the location of the prototype. + if (FDecl && !FDecl->getBuiltinID() && !IsExecConfig) + Diag(FDecl->getLocStart(), diag::note_callee_decl) + << FDecl; + + // This deletes the extra arguments. + Call->setNumArgs(Context, NumArgsInProto); + return true; + } + } + SmallVector<Expr *, 8> AllArgs; + VariadicCallType CallType = + Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; + if (Fn->getType()->isBlockPointerType()) + CallType = VariadicBlock; // Block + else if (isa<MemberExpr>(Fn)) + CallType = VariadicMethod; + Invalid = GatherArgumentsForCall(Call->getLocStart(), FDecl, + Proto, 0, Args, NumArgs, AllArgs, CallType); + if (Invalid) + return true; + unsigned TotalNumArgs = AllArgs.size(); + for (unsigned i = 0; i < TotalNumArgs; ++i) + Call->setArg(i, AllArgs[i]); + + return false; +} + +bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, + FunctionDecl *FDecl, + const FunctionProtoType *Proto, + unsigned FirstProtoArg, + Expr **Args, unsigned NumArgs, + SmallVector<Expr *, 8> &AllArgs, + VariadicCallType CallType, + bool AllowExplicit) { + unsigned NumArgsInProto = Proto->getNumArgs(); + unsigned NumArgsToCheck = NumArgs; + bool Invalid = false; + if (NumArgs != NumArgsInProto) + // Use default arguments for missing arguments + NumArgsToCheck = NumArgsInProto; + unsigned ArgIx = 0; + // Continue to check argument types (even if we have too few/many args). + for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { + QualType ProtoArgType = Proto->getArgType(i); + + Expr *Arg; + ParmVarDecl *Param; + if (ArgIx < NumArgs) { + Arg = Args[ArgIx++]; + + if (RequireCompleteType(Arg->getLocStart(), + ProtoArgType, + PDiag(diag::err_call_incomplete_argument) + << Arg->getSourceRange())) + return true; + + // Pass the argument + Param = 0; + if (FDecl && i < FDecl->getNumParams()) + Param = FDecl->getParamDecl(i); + + // Strip the unbridged-cast placeholder expression off, if applicable. + if (Arg->getType() == Context.ARCUnbridgedCastTy && + FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() && + (!Param || !Param->hasAttr<CFConsumedAttr>())) + Arg = stripARCUnbridgedCast(Arg); + + InitializedEntity Entity = + Param? InitializedEntity::InitializeParameter(Context, Param) + : InitializedEntity::InitializeParameter(Context, ProtoArgType, + Proto->isArgConsumed(i)); + ExprResult ArgE = PerformCopyInitialization(Entity, + SourceLocation(), + Owned(Arg), + /*TopLevelOfInitList=*/false, + AllowExplicit); + if (ArgE.isInvalid()) + return true; + + Arg = ArgE.takeAs<Expr>(); + } else { + Param = FDecl->getParamDecl(i); + + ExprResult ArgExpr = + BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); + if (ArgExpr.isInvalid()) + return true; + + Arg = ArgExpr.takeAs<Expr>(); + } + + // Check for array bounds violations for each argument to the call. This + // check only triggers warnings when the argument isn't a more complex Expr + // with its own checking, such as a BinaryOperator. + CheckArrayAccess(Arg); + + // Check for violations of C99 static array rules (C99 6.7.5.3p7). + CheckStaticArrayArgument(CallLoc, Param, Arg); + + AllArgs.push_back(Arg); + } + + // If this is a variadic call, handle args passed through "...". + if (CallType != VariadicDoesNotApply) { + + // Assume that extern "C" functions with variadic arguments that + // return __unknown_anytype aren't *really* variadic. + if (Proto->getResultType() == Context.UnknownAnyTy && + FDecl && FDecl->isExternC()) { + for (unsigned i = ArgIx; i != NumArgs; ++i) { + ExprResult arg; + if (isa<ExplicitCastExpr>(Args[i]->IgnoreParens())) + arg = DefaultFunctionArrayLvalueConversion(Args[i]); + else + arg = DefaultVariadicArgumentPromotion(Args[i], CallType, FDecl); + Invalid |= arg.isInvalid(); + AllArgs.push_back(arg.take()); + } + + // Otherwise do argument promotion, (C99 6.5.2.2p7). + } else { + for (unsigned i = ArgIx; i != NumArgs; ++i) { + ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], CallType, + FDecl); + Invalid |= Arg.isInvalid(); + AllArgs.push_back(Arg.take()); + } + } + + // Check for array bounds violations. + for (unsigned i = ArgIx; i != NumArgs; ++i) + CheckArrayAccess(Args[i]); + } + return Invalid; +} + +static void DiagnoseCalleeStaticArrayParam(Sema &S, ParmVarDecl *PVD) { + TypeLoc TL = PVD->getTypeSourceInfo()->getTypeLoc(); + if (ArrayTypeLoc *ATL = dyn_cast<ArrayTypeLoc>(&TL)) + S.Diag(PVD->getLocation(), diag::note_callee_static_array) + << ATL->getLocalSourceRange(); +} + +/// CheckStaticArrayArgument - If the given argument corresponds to a static +/// array parameter, check that it is non-null, and that if it is formed by +/// array-to-pointer decay, the underlying array is sufficiently large. +/// +/// C99 6.7.5.3p7: If the keyword static also appears within the [ and ] of the +/// array type derivation, then for each call to the function, the value of the +/// corresponding actual argument shall provide access to the first element of +/// an array with at least as many elements as specified by the size expression. +void +Sema::CheckStaticArrayArgument(SourceLocation CallLoc, + ParmVarDecl *Param, + const Expr *ArgExpr) { + // Static array parameters are not supported in C++. + if (!Param || getLangOpts().CPlusPlus) + return; + + QualType OrigTy = Param->getOriginalType(); + + const ArrayType *AT = Context.getAsArrayType(OrigTy); + if (!AT || AT->getSizeModifier() != ArrayType::Static) + return; + + if (ArgExpr->isNullPointerConstant(Context, + Expr::NPC_NeverValueDependent)) { + Diag(CallLoc, diag::warn_null_arg) << ArgExpr->getSourceRange(); + DiagnoseCalleeStaticArrayParam(*this, Param); + return; + } + + const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT); + if (!CAT) + return; + + const ConstantArrayType *ArgCAT = + Context.getAsConstantArrayType(ArgExpr->IgnoreParenImpCasts()->getType()); + if (!ArgCAT) + return; + + if (ArgCAT->getSize().ult(CAT->getSize())) { + Diag(CallLoc, diag::warn_static_array_too_small) + << ArgExpr->getSourceRange() + << (unsigned) ArgCAT->getSize().getZExtValue() + << (unsigned) CAT->getSize().getZExtValue(); + DiagnoseCalleeStaticArrayParam(*this, Param); + } +} + +/// Given a function expression of unknown-any type, try to rebuild it +/// to have a function type. +static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn); + +/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. +/// This provides the location of the left/right parens and a list of comma +/// locations. +ExprResult +Sema::ActOnCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc, + MultiExprArg ArgExprs, SourceLocation RParenLoc, + Expr *ExecConfig, bool IsExecConfig) { + unsigned NumArgs = ArgExprs.size(); + + // Since this might be a postfix expression, get rid of ParenListExprs. + ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Fn); + if (Result.isInvalid()) return ExprError(); + Fn = Result.take(); + + Expr **Args = ArgExprs.release(); + + if (getLangOpts().CPlusPlus) { + // If this is a pseudo-destructor expression, build the call immediately. + if (isa<CXXPseudoDestructorExpr>(Fn)) { + if (NumArgs > 0) { + // Pseudo-destructor calls should not have any arguments. + Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) + << FixItHint::CreateRemoval( + SourceRange(Args[0]->getLocStart(), + Args[NumArgs-1]->getLocEnd())); + } + + return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, + VK_RValue, RParenLoc)); + } + + // Determine whether this is a dependent call inside a C++ template, + // in which case we won't do any semantic analysis now. + // FIXME: Will need to cache the results of name lookup (including ADL) in + // Fn. + bool Dependent = false; + if (Fn->isTypeDependent()) + Dependent = true; + else if (Expr::hasAnyTypeDependentArguments( + llvm::makeArrayRef(Args, NumArgs))) + Dependent = true; + + if (Dependent) { + if (ExecConfig) { + return Owned(new (Context) CUDAKernelCallExpr( + Context, Fn, cast<CallExpr>(ExecConfig), Args, NumArgs, + Context.DependentTy, VK_RValue, RParenLoc)); + } else { + return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, + Context.DependentTy, VK_RValue, + RParenLoc)); + } + } + + // Determine whether this is a call to an object (C++ [over.call.object]). + if (Fn->getType()->isRecordType()) + return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, + RParenLoc)); + + if (Fn->getType() == Context.UnknownAnyTy) { + ExprResult result = rebuildUnknownAnyFunction(*this, Fn); + if (result.isInvalid()) return ExprError(); + Fn = result.take(); + } + + if (Fn->getType() == Context.BoundMemberTy) { + return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, + RParenLoc); + } + } + + // Check for overloaded calls. This can happen even in C due to extensions. + if (Fn->getType() == Context.OverloadTy) { + OverloadExpr::FindResult find = OverloadExpr::find(Fn); + + // We aren't supposed to apply this logic for if there's an '&' involved. + if (!find.HasFormOfMemberPointer) { + OverloadExpr *ovl = find.Expression; + if (isa<UnresolvedLookupExpr>(ovl)) { + UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(ovl); + return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, + RParenLoc, ExecConfig); + } else { + return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, + RParenLoc); + } + } + } + + // If we're directly calling a function, get the appropriate declaration. + if (Fn->getType() == Context.UnknownAnyTy) { + ExprResult result = rebuildUnknownAnyFunction(*this, Fn); + if (result.isInvalid()) return ExprError(); + Fn = result.take(); + } + + Expr *NakedFn = Fn->IgnoreParens(); + + NamedDecl *NDecl = 0; + if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(NakedFn)) + if (UnOp->getOpcode() == UO_AddrOf) + NakedFn = UnOp->getSubExpr()->IgnoreParens(); + + if (isa<DeclRefExpr>(NakedFn)) + NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); + else if (isa<MemberExpr>(NakedFn)) + NDecl = cast<MemberExpr>(NakedFn)->getMemberDecl(); + + return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc, + ExecConfig, IsExecConfig); +} + +ExprResult +Sema::ActOnCUDAExecConfigExpr(Scope *S, SourceLocation LLLLoc, + MultiExprArg ExecConfig, SourceLocation GGGLoc) { + FunctionDecl *ConfigDecl = Context.getcudaConfigureCallDecl(); + if (!ConfigDecl) + return ExprError(Diag(LLLLoc, diag::err_undeclared_var_use) + << "cudaConfigureCall"); + QualType ConfigQTy = ConfigDecl->getType(); + + DeclRefExpr *ConfigDR = new (Context) DeclRefExpr( + ConfigDecl, false, ConfigQTy, VK_LValue, LLLLoc); + MarkFunctionReferenced(LLLLoc, ConfigDecl); + + return ActOnCallExpr(S, ConfigDR, LLLLoc, ExecConfig, GGGLoc, 0, + /*IsExecConfig=*/true); +} + +/// ActOnAsTypeExpr - create a new asType (bitcast) from the arguments. +/// +/// __builtin_astype( value, dst type ) +/// +ExprResult Sema::ActOnAsTypeExpr(Expr *E, ParsedType ParsedDestTy, + SourceLocation BuiltinLoc, + SourceLocation RParenLoc) { + ExprValueKind VK = VK_RValue; + ExprObjectKind OK = OK_Ordinary; + QualType DstTy = GetTypeFromParser(ParsedDestTy); + QualType SrcTy = E->getType(); + if (Context.getTypeSize(DstTy) != Context.getTypeSize(SrcTy)) + return ExprError(Diag(BuiltinLoc, + diag::err_invalid_astype_of_different_size) + << DstTy + << SrcTy + << E->getSourceRange()); + return Owned(new (Context) AsTypeExpr(E, DstTy, VK, OK, BuiltinLoc, + RParenLoc)); +} + +/// BuildResolvedCallExpr - Build a call to a resolved expression, +/// i.e. an expression not of \p OverloadTy. The expression should +/// unary-convert to an expression of function-pointer or +/// block-pointer type. +/// +/// \param NDecl the declaration being called, if available +ExprResult +Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, + SourceLocation LParenLoc, + Expr **Args, unsigned NumArgs, + SourceLocation RParenLoc, + Expr *Config, bool IsExecConfig) { + FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); + + // Promote the function operand. + ExprResult Result = UsualUnaryConversions(Fn); + if (Result.isInvalid()) + return ExprError(); + Fn = Result.take(); + + // Make the call expr early, before semantic checks. This guarantees cleanup + // of arguments and function on error. + CallExpr *TheCall; + if (Config) { + TheCall = new (Context) CUDAKernelCallExpr(Context, Fn, + cast<CallExpr>(Config), + Args, NumArgs, + Context.BoolTy, + VK_RValue, + RParenLoc); + } else { + TheCall = new (Context) CallExpr(Context, Fn, + Args, NumArgs, + Context.BoolTy, + VK_RValue, + RParenLoc); + } + + unsigned BuiltinID = (FDecl ? FDecl->getBuiltinID() : 0); + + // Bail out early if calling a builtin with custom typechecking. + if (BuiltinID && Context.BuiltinInfo.hasCustomTypechecking(BuiltinID)) + return CheckBuiltinFunctionCall(BuiltinID, TheCall); + + retry: + const FunctionType *FuncT; + if (const PointerType *PT = Fn->getType()->getAs<PointerType>()) { + // C99 6.5.2.2p1 - "The expression that denotes the called function shall + // have type pointer to function". + FuncT = PT->getPointeeType()->getAs<FunctionType>(); + if (FuncT == 0) + return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) + << Fn->getType() << Fn->getSourceRange()); + } else if (const BlockPointerType *BPT = + Fn->getType()->getAs<BlockPointerType>()) { + FuncT = BPT->getPointeeType()->castAs<FunctionType>(); + } else { + // Handle calls to expressions of unknown-any type. + if (Fn->getType() == Context.UnknownAnyTy) { + ExprResult rewrite = rebuildUnknownAnyFunction(*this, Fn); + if (rewrite.isInvalid()) return ExprError(); + Fn = rewrite.take(); + TheCall->setCallee(Fn); + goto retry; + } + + return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) + << Fn->getType() << Fn->getSourceRange()); + } + + if (getLangOpts().CUDA) { + if (Config) { + // CUDA: Kernel calls must be to global functions + if (FDecl && !FDecl->hasAttr<CUDAGlobalAttr>()) + return ExprError(Diag(LParenLoc,diag::err_kern_call_not_global_function) + << FDecl->getName() << Fn->getSourceRange()); + + // CUDA: Kernel function must have 'void' return type + if (!FuncT->getResultType()->isVoidType()) + return ExprError(Diag(LParenLoc, diag::err_kern_type_not_void_return) + << Fn->getType() << Fn->getSourceRange()); + } else { + // CUDA: Calls to global functions must be configured + if (FDecl && FDecl->hasAttr<CUDAGlobalAttr>()) + return ExprError(Diag(LParenLoc, diag::err_global_call_not_config) + << FDecl->getName() << Fn->getSourceRange()); + } + } + + // Check for a valid return type + if (CheckCallReturnType(FuncT->getResultType(), + Fn->getLocStart(), TheCall, + FDecl)) + return ExprError(); + + // We know the result type of the call, set it. + TheCall->setType(FuncT->getCallResultType(Context)); + TheCall->setValueKind(Expr::getValueKindForType(FuncT->getResultType())); + + if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { + if (ConvertArgumentsForCall(TheCall, Fn, FDecl, Proto, Args, NumArgs, + RParenLoc, IsExecConfig)) + return ExprError(); + } else { + assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); + + if (FDecl) { + // Check if we have too few/too many template arguments, based + // on our knowledge of the function definition. + const FunctionDecl *Def = 0; + if (FDecl->hasBody(Def) && NumArgs != Def->param_size()) { + const FunctionProtoType *Proto + = Def->getType()->getAs<FunctionProtoType>(); + if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) + Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) + << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); + } + + // If the function we're calling isn't a function prototype, but we have + // a function prototype from a prior declaratiom, use that prototype. + if (!FDecl->hasPrototype()) + Proto = FDecl->getType()->getAs<FunctionProtoType>(); + } + + // Promote the arguments (C99 6.5.2.2p6). + for (unsigned i = 0; i != NumArgs; i++) { + Expr *Arg = Args[i]; + + if (Proto && i < Proto->getNumArgs()) { + InitializedEntity Entity + = InitializedEntity::InitializeParameter(Context, + Proto->getArgType(i), + Proto->isArgConsumed(i)); + ExprResult ArgE = PerformCopyInitialization(Entity, + SourceLocation(), + Owned(Arg)); + if (ArgE.isInvalid()) + return true; + + Arg = ArgE.takeAs<Expr>(); + + } else { + ExprResult ArgE = DefaultArgumentPromotion(Arg); + + if (ArgE.isInvalid()) + return true; + + Arg = ArgE.takeAs<Expr>(); + } + + if (RequireCompleteType(Arg->getLocStart(), + Arg->getType(), + PDiag(diag::err_call_incomplete_argument) + << Arg->getSourceRange())) + return ExprError(); + + TheCall->setArg(i, Arg); + } + } + + if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) + if (!Method->isStatic()) + return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) + << Fn->getSourceRange()); + + // Check for sentinels + if (NDecl) + DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); + + // Do special checking on direct calls to functions. + if (FDecl) { + if (CheckFunctionCall(FDecl, TheCall)) + return ExprError(); + + if (BuiltinID) + return CheckBuiltinFunctionCall(BuiltinID, TheCall); + } else if (NDecl) { + if (CheckBlockCall(NDecl, TheCall)) + return ExprError(); + } + + return MaybeBindToTemporary(TheCall); +} + +ExprResult +Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty, + SourceLocation RParenLoc, Expr *InitExpr) { + assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); + // FIXME: put back this assert when initializers are worked out. + //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); + + TypeSourceInfo *TInfo; + QualType literalType = GetTypeFromParser(Ty, &TInfo); + if (!TInfo) + TInfo = Context.getTrivialTypeSourceInfo(literalType); + + return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, InitExpr); +} + +ExprResult +Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, + SourceLocation RParenLoc, Expr *LiteralExpr) { + QualType literalType = TInfo->getType(); + + if (literalType->isArrayType()) { + if (RequireCompleteType(LParenLoc, Context.getBaseElementType(literalType), + PDiag(diag::err_illegal_decl_array_incomplete_type) + << SourceRange(LParenLoc, + LiteralExpr->getSourceRange().getEnd()))) + return ExprError(); + if (literalType->isVariableArrayType()) + return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) + << SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd())); + } else if (!literalType->isDependentType() && + RequireCompleteType(LParenLoc, literalType, + PDiag(diag::err_typecheck_decl_incomplete_type) + << SourceRange(LParenLoc, + LiteralExpr->getSourceRange().getEnd()))) + return ExprError(); + + InitializedEntity Entity + = InitializedEntity::InitializeTemporary(literalType); + InitializationKind Kind + = InitializationKind::CreateCStyleCast(LParenLoc, + SourceRange(LParenLoc, RParenLoc), + /*InitList=*/true); + InitializationSequence InitSeq(*this, Entity, Kind, &LiteralExpr, 1); + ExprResult Result = InitSeq.Perform(*this, Entity, Kind, + MultiExprArg(*this, &LiteralExpr, 1), + &literalType); + if (Result.isInvalid()) + return ExprError(); + LiteralExpr = Result.get(); + + bool isFileScope = getCurFunctionOrMethodDecl() == 0; + if (isFileScope) { // 6.5.2.5p3 + if (CheckForConstantInitializer(LiteralExpr, literalType)) + return ExprError(); + } + + // In C, compound literals are l-values for some reason. + ExprValueKind VK = getLangOpts().CPlusPlus ? VK_RValue : VK_LValue; + + return MaybeBindToTemporary( + new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, + VK, LiteralExpr, isFileScope)); +} + +ExprResult +Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg InitArgList, + SourceLocation RBraceLoc) { + unsigned NumInit = InitArgList.size(); + Expr **InitList = InitArgList.release(); + + // Immediately handle non-overload placeholders. Overloads can be + // resolved contextually, but everything else here can't. + for (unsigned I = 0; I != NumInit; ++I) { + if (InitList[I]->getType()->isNonOverloadPlaceholderType()) { + ExprResult result = CheckPlaceholderExpr(InitList[I]); + + // Ignore failures; dropping the entire initializer list because + // of one failure would be terrible for indexing/etc. + if (result.isInvalid()) continue; + + InitList[I] = result.take(); + } + } + + // Semantic analysis for initializers is done by ActOnDeclarator() and + // CheckInitializer() - it requires knowledge of the object being intialized. + + InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, + NumInit, RBraceLoc); + E->setType(Context.VoidTy); // FIXME: just a place holder for now. + return Owned(E); +} + +/// Do an explicit extend of the given block pointer if we're in ARC. +static void maybeExtendBlockObject(Sema &S, ExprResult &E) { + assert(E.get()->getType()->isBlockPointerType()); + assert(E.get()->isRValue()); + + // Only do this in an r-value context. + if (!S.getLangOpts().ObjCAutoRefCount) return; + + E = ImplicitCastExpr::Create(S.Context, E.get()->getType(), + CK_ARCExtendBlockObject, E.get(), + /*base path*/ 0, VK_RValue); + S.ExprNeedsCleanups = true; +} + +/// Prepare a conversion of the given expression to an ObjC object +/// pointer type. +CastKind Sema::PrepareCastToObjCObjectPointer(ExprResult &E) { + QualType type = E.get()->getType(); + if (type->isObjCObjectPointerType()) { + return CK_BitCast; + } else if (type->isBlockPointerType()) { + maybeExtendBlockObject(*this, E); + return CK_BlockPointerToObjCPointerCast; + } else { + assert(type->isPointerType()); + return CK_CPointerToObjCPointerCast; + } +} + +/// Prepares for a scalar cast, performing all the necessary stages +/// except the final cast and returning the kind required. +CastKind Sema::PrepareScalarCast(ExprResult &Src, QualType DestTy) { + // Both Src and Dest are scalar types, i.e. arithmetic or pointer. + // Also, callers should have filtered out the invalid cases with + // pointers. Everything else should be possible. + + QualType SrcTy = Src.get()->getType(); + if (const AtomicType *SrcAtomicTy = SrcTy->getAs<AtomicType>()) + SrcTy = SrcAtomicTy->getValueType(); + if (const AtomicType *DestAtomicTy = DestTy->getAs<AtomicType>()) + DestTy = DestAtomicTy->getValueType(); + + if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) + return CK_NoOp; + + switch (Type::ScalarTypeKind SrcKind = SrcTy->getScalarTypeKind()) { + case Type::STK_MemberPointer: + llvm_unreachable("member pointer type in C"); + + case Type::STK_CPointer: + case Type::STK_BlockPointer: + case Type::STK_ObjCObjectPointer: + switch (DestTy->getScalarTypeKind()) { + case Type::STK_CPointer: + return CK_BitCast; + case Type::STK_BlockPointer: + return (SrcKind == Type::STK_BlockPointer + ? CK_BitCast : CK_AnyPointerToBlockPointerCast); + case Type::STK_ObjCObjectPointer: + if (SrcKind == Type::STK_ObjCObjectPointer) + return CK_BitCast; + if (SrcKind == Type::STK_CPointer) + return CK_CPointerToObjCPointerCast; + maybeExtendBlockObject(*this, Src); + return CK_BlockPointerToObjCPointerCast; + case Type::STK_Bool: + return CK_PointerToBoolean; + case Type::STK_Integral: + return CK_PointerToIntegral; + case Type::STK_Floating: + case Type::STK_FloatingComplex: + case Type::STK_IntegralComplex: + case Type::STK_MemberPointer: + llvm_unreachable("illegal cast from pointer"); + } + llvm_unreachable("Should have returned before this"); + + case Type::STK_Bool: // casting from bool is like casting from an integer + case Type::STK_Integral: + switch (DestTy->getScalarTypeKind()) { + case Type::STK_CPointer: + case Type::STK_ObjCObjectPointer: + case Type::STK_BlockPointer: + if (Src.get()->isNullPointerConstant(Context, + Expr::NPC_ValueDependentIsNull)) + return CK_NullToPointer; + return CK_IntegralToPointer; + case Type::STK_Bool: + return CK_IntegralToBoolean; + case Type::STK_Integral: + return CK_IntegralCast; + case Type::STK_Floating: + return CK_IntegralToFloating; + case Type::STK_IntegralComplex: + Src = ImpCastExprToType(Src.take(), + DestTy->castAs<ComplexType>()->getElementType(), + CK_IntegralCast); + return CK_IntegralRealToComplex; + case Type::STK_FloatingComplex: + Src = ImpCastExprToType(Src.take(), + DestTy->castAs<ComplexType>()->getElementType(), + CK_IntegralToFloating); + return CK_FloatingRealToComplex; + case Type::STK_MemberPointer: + llvm_unreachable("member pointer type in C"); + } + llvm_unreachable("Should have returned before this"); + + case Type::STK_Floating: + switch (DestTy->getScalarTypeKind()) { + case Type::STK_Floating: + return CK_FloatingCast; + case Type::STK_Bool: + return CK_FloatingToBoolean; + case Type::STK_Integral: + return CK_FloatingToIntegral; + case Type::STK_FloatingComplex: + Src = ImpCastExprToType(Src.take(), + DestTy->castAs<ComplexType>()->getElementType(), + CK_FloatingCast); + return CK_FloatingRealToComplex; + case Type::STK_IntegralComplex: + Src = ImpCastExprToType(Src.take(), + DestTy->castAs<ComplexType>()->getElementType(), + CK_FloatingToIntegral); + return CK_IntegralRealToComplex; + case Type::STK_CPointer: + case Type::STK_ObjCObjectPointer: + case Type::STK_BlockPointer: + llvm_unreachable("valid float->pointer cast?"); + case Type::STK_MemberPointer: + llvm_unreachable("member pointer type in C"); + } + llvm_unreachable("Should have returned before this"); + + case Type::STK_FloatingComplex: + switch (DestTy->getScalarTypeKind()) { + case Type::STK_FloatingComplex: + return CK_FloatingComplexCast; + case Type::STK_IntegralComplex: + return CK_FloatingComplexToIntegralComplex; + case Type::STK_Floating: { + QualType ET = SrcTy->castAs<ComplexType>()->getElementType(); + if (Context.hasSameType(ET, DestTy)) + return CK_FloatingComplexToReal; + Src = ImpCastExprToType(Src.take(), ET, CK_FloatingComplexToReal); + return CK_FloatingCast; + } + case Type::STK_Bool: + return CK_FloatingComplexToBoolean; + case Type::STK_Integral: + Src = ImpCastExprToType(Src.take(), + SrcTy->castAs<ComplexType>()->getElementType(), + CK_FloatingComplexToReal); + return CK_FloatingToIntegral; + case Type::STK_CPointer: + case Type::STK_ObjCObjectPointer: + case Type::STK_BlockPointer: + llvm_unreachable("valid complex float->pointer cast?"); + case Type::STK_MemberPointer: + llvm_unreachable("member pointer type in C"); + } + llvm_unreachable("Should have returned before this"); + + case Type::STK_IntegralComplex: + switch (DestTy->getScalarTypeKind()) { + case Type::STK_FloatingComplex: + return CK_IntegralComplexToFloatingComplex; + case Type::STK_IntegralComplex: + return CK_IntegralComplexCast; + case Type::STK_Integral: { + QualType ET = SrcTy->castAs<ComplexType>()->getElementType(); + if (Context.hasSameType(ET, DestTy)) + return CK_IntegralComplexToReal; + Src = ImpCastExprToType(Src.take(), ET, CK_IntegralComplexToReal); + return CK_IntegralCast; + } + case Type::STK_Bool: + return CK_IntegralComplexToBoolean; + case Type::STK_Floating: + Src = ImpCastExprToType(Src.take(), + SrcTy->castAs<ComplexType>()->getElementType(), + CK_IntegralComplexToReal); + return CK_IntegralToFloating; + case Type::STK_CPointer: + case Type::STK_ObjCObjectPointer: + case Type::STK_BlockPointer: + llvm_unreachable("valid complex int->pointer cast?"); + case Type::STK_MemberPointer: + llvm_unreachable("member pointer type in C"); + } + llvm_unreachable("Should have returned before this"); + } + + llvm_unreachable("Unhandled scalar cast"); +} + +bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, + CastKind &Kind) { + assert(VectorTy->isVectorType() && "Not a vector type!"); + + if (Ty->isVectorType() || Ty->isIntegerType()) { + if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) + return Diag(R.getBegin(), + Ty->isVectorType() ? + diag::err_invalid_conversion_between_vectors : + diag::err_invalid_conversion_between_vector_and_integer) + << VectorTy << Ty << R; + } else + return Diag(R.getBegin(), + diag::err_invalid_conversion_between_vector_and_scalar) + << VectorTy << Ty << R; + + Kind = CK_BitCast; + return false; +} + +ExprResult Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, + Expr *CastExpr, CastKind &Kind) { + assert(DestTy->isExtVectorType() && "Not an extended vector type!"); + + QualType SrcTy = CastExpr->getType(); + + // If SrcTy is a VectorType, the total size must match to explicitly cast to + // an ExtVectorType. + // In OpenCL, casts between vectors of different types are not allowed. + // (See OpenCL 6.2). + if (SrcTy->isVectorType()) { + if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy) + || (getLangOpts().OpenCL && + (DestTy.getCanonicalType() != SrcTy.getCanonicalType()))) { + Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) + << DestTy << SrcTy << R; + return ExprError(); + } + Kind = CK_BitCast; + return Owned(CastExpr); + } + + // All non-pointer scalars can be cast to ExtVector type. The appropriate + // conversion will take place first from scalar to elt type, and then + // splat from elt type to vector. + if (SrcTy->isPointerType()) + return Diag(R.getBegin(), + diag::err_invalid_conversion_between_vector_and_scalar) + << DestTy << SrcTy << R; + + QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); + ExprResult CastExprRes = Owned(CastExpr); + CastKind CK = PrepareScalarCast(CastExprRes, DestElemTy); + if (CastExprRes.isInvalid()) + return ExprError(); + CastExpr = ImpCastExprToType(CastExprRes.take(), DestElemTy, CK).take(); + + Kind = CK_VectorSplat; + return Owned(CastExpr); +} + +ExprResult +Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, + Declarator &D, ParsedType &Ty, + SourceLocation RParenLoc, Expr *CastExpr) { + assert(!D.isInvalidType() && (CastExpr != 0) && + "ActOnCastExpr(): missing type or expr"); + + TypeSourceInfo *castTInfo = GetTypeForDeclaratorCast(D, CastExpr->getType()); + if (D.isInvalidType()) + return ExprError(); + + if (getLangOpts().CPlusPlus) { + // Check that there are no default arguments (C++ only). + CheckExtraCXXDefaultArguments(D); + } + + checkUnusedDeclAttributes(D); + + QualType castType = castTInfo->getType(); + Ty = CreateParsedType(castType, castTInfo); + + bool isVectorLiteral = false; + + // Check for an altivec or OpenCL literal, + // i.e. all the elements are integer constants. + ParenExpr *PE = dyn_cast<ParenExpr>(CastExpr); + ParenListExpr *PLE = dyn_cast<ParenListExpr>(CastExpr); + if ((getLangOpts().AltiVec || getLangOpts().OpenCL) + && castType->isVectorType() && (PE || PLE)) { + if (PLE && PLE->getNumExprs() == 0) { + Diag(PLE->getExprLoc(), diag::err_altivec_empty_initializer); + return ExprError(); + } + if (PE || PLE->getNumExprs() == 1) { + Expr *E = (PE ? PE->getSubExpr() : PLE->getExpr(0)); + if (!E->getType()->isVectorType()) + isVectorLiteral = true; + } + else + isVectorLiteral = true; + } + + // If this is a vector initializer, '(' type ')' '(' init, ..., init ')' + // then handle it as such. + if (isVectorLiteral) + return BuildVectorLiteral(LParenLoc, RParenLoc, CastExpr, castTInfo); + + // If the Expr being casted is a ParenListExpr, handle it specially. + // This is not an AltiVec-style cast, so turn the ParenListExpr into a + // sequence of BinOp comma operators. + if (isa<ParenListExpr>(CastExpr)) { + ExprResult Result = MaybeConvertParenListExprToParenExpr(S, CastExpr); + if (Result.isInvalid()) return ExprError(); + CastExpr = Result.take(); + } + + return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, CastExpr); +} + +ExprResult Sema::BuildVectorLiteral(SourceLocation LParenLoc, + SourceLocation RParenLoc, Expr *E, + TypeSourceInfo *TInfo) { + assert((isa<ParenListExpr>(E) || isa<ParenExpr>(E)) && + "Expected paren or paren list expression"); + + Expr **exprs; + unsigned numExprs; + Expr *subExpr; + if (ParenListExpr *PE = dyn_cast<ParenListExpr>(E)) { + exprs = PE->getExprs(); + numExprs = PE->getNumExprs(); + } else { + subExpr = cast<ParenExpr>(E)->getSubExpr(); + exprs = &subExpr; + numExprs = 1; + } + + QualType Ty = TInfo->getType(); + assert(Ty->isVectorType() && "Expected vector type"); + + SmallVector<Expr *, 8> initExprs; + const VectorType *VTy = Ty->getAs<VectorType>(); + unsigned numElems = Ty->getAs<VectorType>()->getNumElements(); + + // '(...)' form of vector initialization in AltiVec: the number of + // initializers must be one or must match the size of the vector. + // If a single value is specified in the initializer then it will be + // replicated to all the components of the vector + if (VTy->getVectorKind() == VectorType::AltiVecVector) { + // The number of initializers must be one or must match the size of the + // vector. If a single value is specified in the initializer then it will + // be replicated to all the components of the vector + if (numExprs == 1) { + QualType ElemTy = Ty->getAs<VectorType>()->getElementType(); + ExprResult Literal = DefaultLvalueConversion(exprs[0]); + if (Literal.isInvalid()) + return ExprError(); + Literal = ImpCastExprToType(Literal.take(), ElemTy, + PrepareScalarCast(Literal, ElemTy)); + return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.take()); + } + else if (numExprs < numElems) { + Diag(E->getExprLoc(), + diag::err_incorrect_number_of_vector_initializers); + return ExprError(); + } + else + initExprs.append(exprs, exprs + numExprs); + } + else { + // For OpenCL, when the number of initializers is a single value, + // it will be replicated to all components of the vector. + if (getLangOpts().OpenCL && + VTy->getVectorKind() == VectorType::GenericVector && + numExprs == 1) { + QualType ElemTy = Ty->getAs<VectorType>()->getElementType(); + ExprResult Literal = DefaultLvalueConversion(exprs[0]); + if (Literal.isInvalid()) + return ExprError(); + Literal = ImpCastExprToType(Literal.take(), ElemTy, + PrepareScalarCast(Literal, ElemTy)); + return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.take()); + } + + initExprs.append(exprs, exprs + numExprs); + } + // FIXME: This means that pretty-printing the final AST will produce curly + // braces instead of the original commas. + InitListExpr *initE = new (Context) InitListExpr(Context, LParenLoc, + &initExprs[0], + initExprs.size(), RParenLoc); + initE->setType(Ty); + return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, initE); +} + +/// This is not an AltiVec-style cast or or C++ direct-initialization, so turn +/// the ParenListExpr into a sequence of comma binary operators. +ExprResult +Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *OrigExpr) { + ParenListExpr *E = dyn_cast<ParenListExpr>(OrigExpr); + if (!E) + return Owned(OrigExpr); + + ExprResult Result(E->getExpr(0)); + + for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) + Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, Result.get(), + E->getExpr(i)); + + if (Result.isInvalid()) return ExprError(); + + return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), Result.get()); +} + +ExprResult Sema::ActOnParenListExpr(SourceLocation L, + SourceLocation R, + MultiExprArg Val) { + unsigned nexprs = Val.size(); + Expr **exprs = reinterpret_cast<Expr**>(Val.release()); + assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); + Expr *expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); + return Owned(expr); +} + +/// \brief Emit a specialized diagnostic when one expression is a null pointer +/// constant and the other is not a pointer. Returns true if a diagnostic is +/// emitted. +bool Sema::DiagnoseConditionalForNull(Expr *LHSExpr, Expr *RHSExpr, + SourceLocation QuestionLoc) { + Expr *NullExpr = LHSExpr; + Expr *NonPointerExpr = RHSExpr; + Expr::NullPointerConstantKind NullKind = + NullExpr->isNullPointerConstant(Context, + Expr::NPC_ValueDependentIsNotNull); + + if (NullKind == Expr::NPCK_NotNull) { + NullExpr = RHSExpr; + NonPointerExpr = LHSExpr; + NullKind = + NullExpr->isNullPointerConstant(Context, + Expr::NPC_ValueDependentIsNotNull); + } + + if (NullKind == Expr::NPCK_NotNull) + return false; + + if (NullKind == Expr::NPCK_ZeroInteger) { + // In this case, check to make sure that we got here from a "NULL" + // string in the source code. + NullExpr = NullExpr->IgnoreParenImpCasts(); + SourceLocation loc = NullExpr->getExprLoc(); + if (!findMacroSpelling(loc, "NULL")) + return false; + } + + int DiagType = (NullKind == Expr::NPCK_CXX0X_nullptr); + Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands_null) + << NonPointerExpr->getType() << DiagType + << NonPointerExpr->getSourceRange(); + return true; +} + +/// \brief Return false if the condition expression is valid, true otherwise. +static bool checkCondition(Sema &S, Expr *Cond) { + QualType CondTy = Cond->getType(); + + // C99 6.5.15p2 + if (CondTy->isScalarType()) return false; + + // OpenCL: Sec 6.3.i says the condition is allowed to be a vector or scalar. + if (S.getLangOpts().OpenCL && CondTy->isVectorType()) + return false; + + // Emit the proper error message. + S.Diag(Cond->getLocStart(), S.getLangOpts().OpenCL ? + diag::err_typecheck_cond_expect_scalar : + diag::err_typecheck_cond_expect_scalar_or_vector) + << CondTy; + return true; +} + +/// \brief Return false if the two expressions can be converted to a vector, +/// true otherwise +static bool checkConditionalConvertScalarsToVectors(Sema &S, ExprResult &LHS, + ExprResult &RHS, + QualType CondTy) { + // Both operands should be of scalar type. + if (!LHS.get()->getType()->isScalarType()) { + S.Diag(LHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) + << CondTy; + return true; + } + if (!RHS.get()->getType()->isScalarType()) { + S.Diag(RHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) + << CondTy; + return true; + } + + // Implicity convert these scalars to the type of the condition. + LHS = S.ImpCastExprToType(LHS.take(), CondTy, CK_IntegralCast); + RHS = S.ImpCastExprToType(RHS.take(), CondTy, CK_IntegralCast); + return false; +} + +/// \brief Handle when one or both operands are void type. +static QualType checkConditionalVoidType(Sema &S, ExprResult &LHS, + ExprResult &RHS) { + Expr *LHSExpr = LHS.get(); + Expr *RHSExpr = RHS.get(); + + if (!LHSExpr->getType()->isVoidType()) + S.Diag(RHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void) + << RHSExpr->getSourceRange(); + if (!RHSExpr->getType()->isVoidType()) + S.Diag(LHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void) + << LHSExpr->getSourceRange(); + LHS = S.ImpCastExprToType(LHS.take(), S.Context.VoidTy, CK_ToVoid); + RHS = S.ImpCastExprToType(RHS.take(), S.Context.VoidTy, CK_ToVoid); + return S.Context.VoidTy; +} + +/// \brief Return false if the NullExpr can be promoted to PointerTy, +/// true otherwise. +static bool checkConditionalNullPointer(Sema &S, ExprResult &NullExpr, + QualType PointerTy) { + if ((!PointerTy->isAnyPointerType() && !PointerTy->isBlockPointerType()) || + !NullExpr.get()->isNullPointerConstant(S.Context, + Expr::NPC_ValueDependentIsNull)) + return true; + + NullExpr = S.ImpCastExprToType(NullExpr.take(), PointerTy, CK_NullToPointer); + return false; +} + +/// \brief Checks compatibility between two pointers and return the resulting +/// type. +static QualType checkConditionalPointerCompatibility(Sema &S, ExprResult &LHS, + ExprResult &RHS, + SourceLocation Loc) { + QualType LHSTy = LHS.get()->getType(); + QualType RHSTy = RHS.get()->getType(); + + if (S.Context.hasSameType(LHSTy, RHSTy)) { + // Two identical pointers types are always compatible. + return LHSTy; + } + + QualType lhptee, rhptee; + + // Get the pointee types. + if (const BlockPointerType *LHSBTy = LHSTy->getAs<BlockPointerType>()) { + lhptee = LHSBTy->getPointeeType(); + rhptee = RHSTy->castAs<BlockPointerType>()->getPointeeType(); + } else { + lhptee = LHSTy->castAs<PointerType>()->getPointeeType(); + rhptee = RHSTy->castAs<PointerType>()->getPointeeType(); + } + + // C99 6.5.15p6: If both operands are pointers to compatible types or to + // differently qualified versions of compatible types, the result type is + // a pointer to an appropriately qualified version of the composite + // type. + + // Only CVR-qualifiers exist in the standard, and the differently-qualified + // clause doesn't make sense for our extensions. E.g. address space 2 should + // be incompatible with address space 3: they may live on different devices or + // anything. + Qualifiers lhQual = lhptee.getQualifiers(); + Qualifiers rhQual = rhptee.getQualifiers(); + + unsigned MergedCVRQual = lhQual.getCVRQualifiers() | rhQual.getCVRQualifiers(); + lhQual.removeCVRQualifiers(); + rhQual.removeCVRQualifiers(); + + lhptee = S.Context.getQualifiedType(lhptee.getUnqualifiedType(), lhQual); + rhptee = S.Context.getQualifiedType(rhptee.getUnqualifiedType(), rhQual); + + QualType CompositeTy = S.Context.mergeTypes(lhptee, rhptee); + + if (CompositeTy.isNull()) { + S.Diag(Loc, diag::warn_typecheck_cond_incompatible_pointers) + << LHSTy << RHSTy << LHS.get()->getSourceRange() + << RHS.get()->getSourceRange(); + // In this situation, we assume void* type. No especially good + // reason, but this is what gcc does, and we do have to pick + // to get a consistent AST. + QualType incompatTy = S.Context.getPointerType(S.Context.VoidTy); + LHS = S.ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); + RHS = S.ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); + return incompatTy; + } + + // The pointer types are compatible. + QualType ResultTy = CompositeTy.withCVRQualifiers(MergedCVRQual); + ResultTy = S.Context.getPointerType(ResultTy); + + LHS = S.ImpCastExprToType(LHS.take(), ResultTy, CK_BitCast); + RHS = S.ImpCastExprToType(RHS.take(), ResultTy, CK_BitCast); + return ResultTy; +} + +/// \brief Return the resulting type when the operands are both block pointers. +static QualType checkConditionalBlockPointerCompatibility(Sema &S, + ExprResult &LHS, + ExprResult &RHS, + SourceLocation Loc) { + QualType LHSTy = LHS.get()->getType(); + QualType RHSTy = RHS.get()->getType(); + + if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { + if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { + QualType destType = S.Context.getPointerType(S.Context.VoidTy); + LHS = S.ImpCastExprToType(LHS.take(), destType, CK_BitCast); + RHS = S.ImpCastExprToType(RHS.take(), destType, CK_BitCast); + return destType; + } + S.Diag(Loc, diag::err_typecheck_cond_incompatible_operands) + << LHSTy << RHSTy << LHS.get()->getSourceRange() + << RHS.get()->getSourceRange(); + return QualType(); + } + + // We have 2 block pointer types. + return checkConditionalPointerCompatibility(S, LHS, RHS, Loc); +} + +/// \brief Return the resulting type when the operands are both pointers. +static QualType +checkConditionalObjectPointersCompatibility(Sema &S, ExprResult &LHS, + ExprResult &RHS, + SourceLocation Loc) { + // get the pointer types + QualType LHSTy = LHS.get()->getType(); + QualType RHSTy = RHS.get()->getType(); + + // get the "pointed to" types + QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); + QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); + + // ignore qualifiers on void (C99 6.5.15p3, clause 6) + if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { + // Figure out necessary qualifiers (C99 6.5.15p6) + QualType destPointee + = S.Context.getQualifiedType(lhptee, rhptee.getQualifiers()); + QualType destType = S.Context.getPointerType(destPointee); + // Add qualifiers if necessary. + LHS = S.ImpCastExprToType(LHS.take(), destType, CK_NoOp); + // Promote to void*. + RHS = S.ImpCastExprToType(RHS.take(), destType, CK_BitCast); + return destType; + } + if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { + QualType destPointee + = S.Context.getQualifiedType(rhptee, lhptee.getQualifiers()); + QualType destType = S.Context.getPointerType(destPointee); + // Add qualifiers if necessary. + RHS = S.ImpCastExprToType(RHS.take(), destType, CK_NoOp); + // Promote to void*. + LHS = S.ImpCastExprToType(LHS.take(), destType, CK_BitCast); + return destType; + } + + return checkConditionalPointerCompatibility(S, LHS, RHS, Loc); +} + +/// \brief Return false if the first expression is not an integer and the second +/// expression is not a pointer, true otherwise. +static bool checkPointerIntegerMismatch(Sema &S, ExprResult &Int, + Expr* PointerExpr, SourceLocation Loc, + bool IsIntFirstExpr) { + if (!PointerExpr->getType()->isPointerType() || + !Int.get()->getType()->isIntegerType()) + return false; + + Expr *Expr1 = IsIntFirstExpr ? Int.get() : PointerExpr; + Expr *Expr2 = IsIntFirstExpr ? PointerExpr : Int.get(); + + S.Diag(Loc, diag::warn_typecheck_cond_pointer_integer_mismatch) + << Expr1->getType() << Expr2->getType() + << Expr1->getSourceRange() << Expr2->getSourceRange(); + Int = S.ImpCastExprToType(Int.take(), PointerExpr->getType(), + CK_IntegralToPointer); + return true; +} + +/// Note that LHS is not null here, even if this is the gnu "x ?: y" extension. +/// In that case, LHS = cond. +/// C99 6.5.15 +QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, + ExprResult &RHS, ExprValueKind &VK, + ExprObjectKind &OK, + SourceLocation QuestionLoc) { + + ExprResult LHSResult = CheckPlaceholderExpr(LHS.get()); + if (!LHSResult.isUsable()) return QualType(); + LHS = move(LHSResult); + + ExprResult RHSResult = CheckPlaceholderExpr(RHS.get()); + if (!RHSResult.isUsable()) return QualType(); + RHS = move(RHSResult); + + // C++ is sufficiently different to merit its own checker. + if (getLangOpts().CPlusPlus) + return CXXCheckConditionalOperands(Cond, LHS, RHS, VK, OK, QuestionLoc); + + VK = VK_RValue; + OK = OK_Ordinary; + + Cond = UsualUnaryConversions(Cond.take()); + if (Cond.isInvalid()) + return QualType(); + LHS = UsualUnaryConversions(LHS.take()); + if (LHS.isInvalid()) + return QualType(); + RHS = UsualUnaryConversions(RHS.take()); + if (RHS.isInvalid()) + return QualType(); + + QualType CondTy = Cond.get()->getType(); + QualType LHSTy = LHS.get()->getType(); + QualType RHSTy = RHS.get()->getType(); + + // first, check the condition. + if (checkCondition(*this, Cond.get())) + return QualType(); + + // Now check the two expressions. + if (LHSTy->isVectorType() || RHSTy->isVectorType()) + return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); + + // OpenCL: If the condition is a vector, and both operands are scalar, + // attempt to implicity convert them to the vector type to act like the + // built in select. + if (getLangOpts().OpenCL && CondTy->isVectorType()) + if (checkConditionalConvertScalarsToVectors(*this, LHS, RHS, CondTy)) + return QualType(); + + // If both operands have arithmetic type, do the usual arithmetic conversions + // to find a common type: C99 6.5.15p3,5. + if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { + UsualArithmeticConversions(LHS, RHS); + if (LHS.isInvalid() || RHS.isInvalid()) + return QualType(); + return LHS.get()->getType(); + } + + // If both operands are the same structure or union type, the result is that + // type. + if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 + if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) + if (LHSRT->getDecl() == RHSRT->getDecl()) + // "If both the operands have structure or union type, the result has + // that type." This implies that CV qualifiers are dropped. + return LHSTy.getUnqualifiedType(); + // FIXME: Type of conditional expression must be complete in C mode. + } + + // C99 6.5.15p5: "If both operands have void type, the result has void type." + // The following || allows only one side to be void (a GCC-ism). + if (LHSTy->isVoidType() || RHSTy->isVoidType()) { + return checkConditionalVoidType(*this, LHS, RHS); + } + + // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has + // the type of the other operand." + if (!checkConditionalNullPointer(*this, RHS, LHSTy)) return LHSTy; + if (!checkConditionalNullPointer(*this, LHS, RHSTy)) return RHSTy; + + // All objective-c pointer type analysis is done here. + QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, + QuestionLoc); + if (LHS.isInvalid() || RHS.isInvalid()) + return QualType(); + if (!compositeType.isNull()) + return compositeType; + + + // Handle block pointer types. + if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) + return checkConditionalBlockPointerCompatibility(*this, LHS, RHS, + QuestionLoc); + + // Check constraints for C object pointers types (C99 6.5.15p3,6). + if (LHSTy->isPointerType() && RHSTy->isPointerType()) + return checkConditionalObjectPointersCompatibility(*this, LHS, RHS, + QuestionLoc); + + // GCC compatibility: soften pointer/integer mismatch. Note that + // null pointers have been filtered out by this point. + if (checkPointerIntegerMismatch(*this, LHS, RHS.get(), QuestionLoc, + /*isIntFirstExpr=*/true)) + return RHSTy; + if (checkPointerIntegerMismatch(*this, RHS, LHS.get(), QuestionLoc, + /*isIntFirstExpr=*/false)) + return LHSTy; + + // Emit a better diagnostic if one of the expressions is a null pointer + // constant and the other is not a pointer type. In this case, the user most + // likely forgot to take the address of the other expression. + if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) + return QualType(); + + // Otherwise, the operands are not compatible. + Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) + << LHSTy << RHSTy << LHS.get()->getSourceRange() + << RHS.get()->getSourceRange(); + return QualType(); +} + +/// FindCompositeObjCPointerType - Helper method to find composite type of +/// two objective-c pointer types of the two input expressions. +QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS, + SourceLocation QuestionLoc) { + QualType LHSTy = LHS.get()->getType(); + QualType RHSTy = RHS.get()->getType(); + + // Handle things like Class and struct objc_class*. Here we case the result + // to the pseudo-builtin, because that will be implicitly cast back to the + // redefinition type if an attempt is made to access its fields. + if (LHSTy->isObjCClassType() && + (Context.hasSameType(RHSTy, Context.getObjCClassRedefinitionType()))) { + RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_CPointerToObjCPointerCast); + return LHSTy; + } + if (RHSTy->isObjCClassType() && + (Context.hasSameType(LHSTy, Context.getObjCClassRedefinitionType()))) { + LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_CPointerToObjCPointerCast); + return RHSTy; + } + // And the same for struct objc_object* / id + if (LHSTy->isObjCIdType() && + (Context.hasSameType(RHSTy, Context.getObjCIdRedefinitionType()))) { + RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_CPointerToObjCPointerCast); + return LHSTy; + } + if (RHSTy->isObjCIdType() && + (Context.hasSameType(LHSTy, Context.getObjCIdRedefinitionType()))) { + LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_CPointerToObjCPointerCast); + return RHSTy; + } + // And the same for struct objc_selector* / SEL + if (Context.isObjCSelType(LHSTy) && + (Context.hasSameType(RHSTy, Context.getObjCSelRedefinitionType()))) { + RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); + return LHSTy; + } + if (Context.isObjCSelType(RHSTy) && + (Context.hasSameType(LHSTy, Context.getObjCSelRedefinitionType()))) { + LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_BitCast); + return RHSTy; + } + // Check constraints for Objective-C object pointers types. + if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { + + if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { + // Two identical object pointer types are always compatible. + return LHSTy; + } + const ObjCObjectPointerType *LHSOPT = LHSTy->castAs<ObjCObjectPointerType>(); + const ObjCObjectPointerType *RHSOPT = RHSTy->castAs<ObjCObjectPointerType>(); + QualType compositeType = LHSTy; + + // If both operands are interfaces and either operand can be + // assigned to the other, use that type as the composite + // type. This allows + // xxx ? (A*) a : (B*) b + // where B is a subclass of A. + // + // Additionally, as for assignment, if either type is 'id' + // allow silent coercion. Finally, if the types are + // incompatible then make sure to use 'id' as the composite + // type so the result is acceptable for sending messages to. + + // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. + // It could return the composite type. + if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { + compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; + } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { + compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; + } else if ((LHSTy->isObjCQualifiedIdType() || + RHSTy->isObjCQualifiedIdType()) && + Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { + // Need to handle "id<xx>" explicitly. + // GCC allows qualified id and any Objective-C type to devolve to + // id. Currently localizing to here until clear this should be + // part of ObjCQualifiedIdTypesAreCompatible. + compositeType = Context.getObjCIdType(); + } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { + compositeType = Context.getObjCIdType(); + } else if (!(compositeType = + Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) + ; + else { + Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) + << LHSTy << RHSTy + << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); + QualType incompatTy = Context.getObjCIdType(); + LHS = ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); + RHS = ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); + return incompatTy; + } + // The object pointer types are compatible. + LHS = ImpCastExprToType(LHS.take(), compositeType, CK_BitCast); + RHS = ImpCastExprToType(RHS.take(), compositeType, CK_BitCast); + return compositeType; + } + // Check Objective-C object pointer types and 'void *' + if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { + if (getLangOpts().ObjCAutoRefCount) { + // ARC forbids the implicit conversion of object pointers to 'void *', + // so these types are not compatible. + Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy + << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); + LHS = RHS = true; + return QualType(); + } + QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); + QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); + QualType destPointee + = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); + QualType destType = Context.getPointerType(destPointee); + // Add qualifiers if necessary. + LHS = ImpCastExprToType(LHS.take(), destType, CK_NoOp); + // Promote to void*. + RHS = ImpCastExprToType(RHS.take(), destType, CK_BitCast); + return destType; + } + if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { + if (getLangOpts().ObjCAutoRefCount) { + // ARC forbids the implicit conversion of object pointers to 'void *', + // so these types are not compatible. + Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy + << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); + LHS = RHS = true; + return QualType(); + } + QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); + QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); + QualType destPointee + = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); + QualType destType = Context.getPointerType(destPointee); + // Add qualifiers if necessary. + RHS = ImpCastExprToType(RHS.take(), destType, CK_NoOp); + // Promote to void*. + LHS = ImpCastExprToType(LHS.take(), destType, CK_BitCast); + return destType; + } + return QualType(); +} + +/// SuggestParentheses - Emit a note with a fixit hint that wraps +/// ParenRange in parentheses. +static void SuggestParentheses(Sema &Self, SourceLocation Loc, + const PartialDiagnostic &Note, + SourceRange ParenRange) { + SourceLocation EndLoc = Self.PP.getLocForEndOfToken(ParenRange.getEnd()); + if (ParenRange.getBegin().isFileID() && ParenRange.getEnd().isFileID() && + EndLoc.isValid()) { + Self.Diag(Loc, Note) + << FixItHint::CreateInsertion(ParenRange.getBegin(), "(") + << FixItHint::CreateInsertion(EndLoc, ")"); + } else { + // We can't display the parentheses, so just show the bare note. + Self.Diag(Loc, Note) << ParenRange; + } +} + +static bool IsArithmeticOp(BinaryOperatorKind Opc) { + return Opc >= BO_Mul && Opc <= BO_Shr; +} + +/// IsArithmeticBinaryExpr - Returns true if E is an arithmetic binary +/// expression, either using a built-in or overloaded operator, +/// and sets *OpCode to the opcode and *RHSExprs to the right-hand side +/// expression. +static bool IsArithmeticBinaryExpr(Expr *E, BinaryOperatorKind *Opcode, + Expr **RHSExprs) { + // Don't strip parenthesis: we should not warn if E is in parenthesis. + E = E->IgnoreImpCasts(); + E = E->IgnoreConversionOperator(); + E = E->IgnoreImpCasts(); + + // Built-in binary operator. + if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) { + if (IsArithmeticOp(OP->getOpcode())) { + *Opcode = OP->getOpcode(); + *RHSExprs = OP->getRHS(); + return true; + } + } + + // Overloaded operator. + if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(E)) { + if (Call->getNumArgs() != 2) + return false; + + // Make sure this is really a binary operator that is safe to pass into + // BinaryOperator::getOverloadedOpcode(), e.g. it's not a subscript op. + OverloadedOperatorKind OO = Call->getOperator(); + if (OO < OO_Plus || OO > OO_Arrow) + return false; + + BinaryOperatorKind OpKind = BinaryOperator::getOverloadedOpcode(OO); + if (IsArithmeticOp(OpKind)) { + *Opcode = OpKind; + *RHSExprs = Call->getArg(1); + return true; + } + } + + return false; +} + +static bool IsLogicOp(BinaryOperatorKind Opc) { + return (Opc >= BO_LT && Opc <= BO_NE) || (Opc >= BO_LAnd && Opc <= BO_LOr); +} + +/// ExprLooksBoolean - Returns true if E looks boolean, i.e. it has boolean type +/// or is a logical expression such as (x==y) which has int type, but is +/// commonly interpreted as boolean. +static bool ExprLooksBoolean(Expr *E) { + E = E->IgnoreParenImpCasts(); + + if (E->getType()->isBooleanType()) + return true; + if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) + return IsLogicOp(OP->getOpcode()); + if (UnaryOperator *OP = dyn_cast<UnaryOperator>(E)) + return OP->getOpcode() == UO_LNot; + + return false; +} + +/// DiagnoseConditionalPrecedence - Emit a warning when a conditional operator +/// and binary operator are mixed in a way that suggests the programmer assumed +/// the conditional operator has higher precedence, for example: +/// "int x = a + someBinaryCondition ? 1 : 2". +static void DiagnoseConditionalPrecedence(Sema &Self, + SourceLocation OpLoc, + Expr *Condition, + Expr *LHSExpr, + Expr *RHSExpr) { + BinaryOperatorKind CondOpcode; + Expr *CondRHS; + + if (!IsArithmeticBinaryExpr(Condition, &CondOpcode, &CondRHS)) + return; + if (!ExprLooksBoolean(CondRHS)) + return; + + // The condition is an arithmetic binary expression, with a right- + // hand side that looks boolean, so warn. + + Self.Diag(OpLoc, diag::warn_precedence_conditional) + << Condition->getSourceRange() + << BinaryOperator::getOpcodeStr(CondOpcode); + + SuggestParentheses(Self, OpLoc, + Self.PDiag(diag::note_precedence_conditional_silence) + << BinaryOperator::getOpcodeStr(CondOpcode), + SourceRange(Condition->getLocStart(), Condition->getLocEnd())); + + SuggestParentheses(Self, OpLoc, + Self.PDiag(diag::note_precedence_conditional_first), + SourceRange(CondRHS->getLocStart(), RHSExpr->getLocEnd())); +} + +/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null +/// in the case of a the GNU conditional expr extension. +ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, + SourceLocation ColonLoc, + Expr *CondExpr, Expr *LHSExpr, + Expr *RHSExpr) { + // If this is the gnu "x ?: y" extension, analyze the types as though the LHS + // was the condition. + OpaqueValueExpr *opaqueValue = 0; + Expr *commonExpr = 0; + if (LHSExpr == 0) { + commonExpr = CondExpr; + + // We usually want to apply unary conversions *before* saving, except + // in the special case of a C++ l-value conditional. + if (!(getLangOpts().CPlusPlus + && !commonExpr->isTypeDependent() + && commonExpr->getValueKind() == RHSExpr->getValueKind() + && commonExpr->isGLValue() + && commonExpr->isOrdinaryOrBitFieldObject() + && RHSExpr->isOrdinaryOrBitFieldObject() + && Context.hasSameType(commonExpr->getType(), RHSExpr->getType()))) { + ExprResult commonRes = UsualUnaryConversions(commonExpr); + if (commonRes.isInvalid()) + return ExprError(); + commonExpr = commonRes.take(); + } + + opaqueValue = new (Context) OpaqueValueExpr(commonExpr->getExprLoc(), + commonExpr->getType(), + commonExpr->getValueKind(), + commonExpr->getObjectKind(), + commonExpr); + LHSExpr = CondExpr = opaqueValue; + } + + ExprValueKind VK = VK_RValue; + ExprObjectKind OK = OK_Ordinary; + ExprResult Cond = Owned(CondExpr), LHS = Owned(LHSExpr), RHS = Owned(RHSExpr); + QualType result = CheckConditionalOperands(Cond, LHS, RHS, + VK, OK, QuestionLoc); + if (result.isNull() || Cond.isInvalid() || LHS.isInvalid() || + RHS.isInvalid()) + return ExprError(); + + DiagnoseConditionalPrecedence(*this, QuestionLoc, Cond.get(), LHS.get(), + RHS.get()); + + if (!commonExpr) + return Owned(new (Context) ConditionalOperator(Cond.take(), QuestionLoc, + LHS.take(), ColonLoc, + RHS.take(), result, VK, OK)); + + return Owned(new (Context) + BinaryConditionalOperator(commonExpr, opaqueValue, Cond.take(), LHS.take(), + RHS.take(), QuestionLoc, ColonLoc, result, VK, + OK)); +} + +// checkPointerTypesForAssignment - This is a very tricky routine (despite +// being closely modeled after the C99 spec:-). The odd characteristic of this +// routine is it effectively iqnores the qualifiers on the top level pointee. +// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. +// FIXME: add a couple examples in this comment. +static Sema::AssignConvertType +checkPointerTypesForAssignment(Sema &S, QualType LHSType, QualType RHSType) { + assert(LHSType.isCanonical() && "LHS not canonicalized!"); + assert(RHSType.isCanonical() && "RHS not canonicalized!"); + + // get the "pointed to" type (ignoring qualifiers at the top level) + const Type *lhptee, *rhptee; + Qualifiers lhq, rhq; + llvm::tie(lhptee, lhq) = cast<PointerType>(LHSType)->getPointeeType().split(); + llvm::tie(rhptee, rhq) = cast<PointerType>(RHSType)->getPointeeType().split(); + + Sema::AssignConvertType ConvTy = Sema::Compatible; + + // C99 6.5.16.1p1: This following citation is common to constraints + // 3 & 4 (below). ...and the type *pointed to* by the left has all the + // qualifiers of the type *pointed to* by the right; + Qualifiers lq; + + // As a special case, 'non-__weak A *' -> 'non-__weak const *' is okay. + if (lhq.getObjCLifetime() != rhq.getObjCLifetime() && + lhq.compatiblyIncludesObjCLifetime(rhq)) { + // Ignore lifetime for further calculation. + lhq.removeObjCLifetime(); + rhq.removeObjCLifetime(); + } + + if (!lhq.compatiblyIncludes(rhq)) { + // Treat address-space mismatches as fatal. TODO: address subspaces + if (lhq.getAddressSpace() != rhq.getAddressSpace()) + ConvTy = Sema::IncompatiblePointerDiscardsQualifiers; + + // It's okay to add or remove GC or lifetime qualifiers when converting to + // and from void*. + else if (lhq.withoutObjCGCAttr().withoutObjCLifetime() + .compatiblyIncludes( + rhq.withoutObjCGCAttr().withoutObjCLifetime()) + && (lhptee->isVoidType() || rhptee->isVoidType())) + ; // keep old + + // Treat lifetime mismatches as fatal. + else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) + ConvTy = Sema::IncompatiblePointerDiscardsQualifiers; + + // For GCC compatibility, other qualifier mismatches are treated + // as still compatible in C. + else ConvTy = Sema::CompatiblePointerDiscardsQualifiers; + } + + // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or + // incomplete type and the other is a pointer to a qualified or unqualified + // version of void... + if (lhptee->isVoidType()) { + if (rhptee->isIncompleteOrObjectType()) + return ConvTy; + + // As an extension, we allow cast to/from void* to function pointer. + assert(rhptee->isFunctionType()); + return Sema::FunctionVoidPointer; + } + + if (rhptee->isVoidType()) { + if (lhptee->isIncompleteOrObjectType()) + return ConvTy; + + // As an extension, we allow cast to/from void* to function pointer. + assert(lhptee->isFunctionType()); + return Sema::FunctionVoidPointer; + } + + // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or + // unqualified versions of compatible types, ... + QualType ltrans = QualType(lhptee, 0), rtrans = QualType(rhptee, 0); + if (!S.Context.typesAreCompatible(ltrans, rtrans)) { + // Check if the pointee types are compatible ignoring the sign. + // We explicitly check for char so that we catch "char" vs + // "unsigned char" on systems where "char" is unsigned. + if (lhptee->isCharType()) + ltrans = S.Context.UnsignedCharTy; + else if (lhptee->hasSignedIntegerRepresentation()) + ltrans = S.Context.getCorrespondingUnsignedType(ltrans); + + if (rhptee->isCharType()) + rtrans = S.Context.UnsignedCharTy; + else if (rhptee->hasSignedIntegerRepresentation()) + rtrans = S.Context.getCorrespondingUnsignedType(rtrans); + + if (ltrans == rtrans) { + // Types are compatible ignoring the sign. Qualifier incompatibility + // takes priority over sign incompatibility because the sign + // warning can be disabled. + if (ConvTy != Sema::Compatible) + return ConvTy; + + return Sema::IncompatiblePointerSign; + } + + // If we are a multi-level pointer, it's possible that our issue is simply + // one of qualification - e.g. char ** -> const char ** is not allowed. If + // the eventual target type is the same and the pointers have the same + // level of indirection, this must be the issue. + if (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)) { + do { + lhptee = cast<PointerType>(lhptee)->getPointeeType().getTypePtr(); + rhptee = cast<PointerType>(rhptee)->getPointeeType().getTypePtr(); + } while (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)); + + if (lhptee == rhptee) + return Sema::IncompatibleNestedPointerQualifiers; + } + + // General pointer incompatibility takes priority over qualifiers. + return Sema::IncompatiblePointer; + } + if (!S.getLangOpts().CPlusPlus && + S.IsNoReturnConversion(ltrans, rtrans, ltrans)) + return Sema::IncompatiblePointer; + return ConvTy; +} + +/// checkBlockPointerTypesForAssignment - This routine determines whether two +/// block pointer types are compatible or whether a block and normal pointer +/// are compatible. It is more restrict than comparing two function pointer +// types. +static Sema::AssignConvertType +checkBlockPointerTypesForAssignment(Sema &S, QualType LHSType, + QualType RHSType) { + assert(LHSType.isCanonical() && "LHS not canonicalized!"); + assert(RHSType.isCanonical() && "RHS not canonicalized!"); + + QualType lhptee, rhptee; + + // get the "pointed to" type (ignoring qualifiers at the top level) + lhptee = cast<BlockPointerType>(LHSType)->getPointeeType(); + rhptee = cast<BlockPointerType>(RHSType)->getPointeeType(); + + // In C++, the types have to match exactly. + if (S.getLangOpts().CPlusPlus) + return Sema::IncompatibleBlockPointer; + + Sema::AssignConvertType ConvTy = Sema::Compatible; + + // For blocks we enforce that qualifiers are identical. + if (lhptee.getLocalQualifiers() != rhptee.getLocalQualifiers()) + ConvTy = Sema::CompatiblePointerDiscardsQualifiers; + + if (!S.Context.typesAreBlockPointerCompatible(LHSType, RHSType)) + return Sema::IncompatibleBlockPointer; + + return ConvTy; +} + +/// checkObjCPointerTypesForAssignment - Compares two objective-c pointer types +/// for assignment compatibility. +static Sema::AssignConvertType +checkObjCPointerTypesForAssignment(Sema &S, QualType LHSType, + QualType RHSType) { + assert(LHSType.isCanonical() && "LHS was not canonicalized!"); + assert(RHSType.isCanonical() && "RHS was not canonicalized!"); + + if (LHSType->isObjCBuiltinType()) { + // Class is not compatible with ObjC object pointers. + if (LHSType->isObjCClassType() && !RHSType->isObjCBuiltinType() && + !RHSType->isObjCQualifiedClassType()) + return Sema::IncompatiblePointer; + return Sema::Compatible; + } + if (RHSType->isObjCBuiltinType()) { + if (RHSType->isObjCClassType() && !LHSType->isObjCBuiltinType() && + !LHSType->isObjCQualifiedClassType()) + return Sema::IncompatiblePointer; + return Sema::Compatible; + } + QualType lhptee = LHSType->getAs<ObjCObjectPointerType>()->getPointeeType(); + QualType rhptee = RHSType->getAs<ObjCObjectPointerType>()->getPointeeType(); + + if (!lhptee.isAtLeastAsQualifiedAs(rhptee) && + // make an exception for id<P> + !LHSType->isObjCQualifiedIdType()) + return Sema::CompatiblePointerDiscardsQualifiers; + + if (S.Context.typesAreCompatible(LHSType, RHSType)) + return Sema::Compatible; + if (LHSType->isObjCQualifiedIdType() || RHSType->isObjCQualifiedIdType()) + return Sema::IncompatibleObjCQualifiedId; + return Sema::IncompatiblePointer; +} + +Sema::AssignConvertType +Sema::CheckAssignmentConstraints(SourceLocation Loc, + QualType LHSType, QualType RHSType) { + // Fake up an opaque expression. We don't actually care about what + // cast operations are required, so if CheckAssignmentConstraints + // adds casts to this they'll be wasted, but fortunately that doesn't + // usually happen on valid code. + OpaqueValueExpr RHSExpr(Loc, RHSType, VK_RValue); + ExprResult RHSPtr = &RHSExpr; + CastKind K = CK_Invalid; + + return CheckAssignmentConstraints(LHSType, RHSPtr, K); +} + +/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently +/// has code to accommodate several GCC extensions when type checking +/// pointers. Here are some objectionable examples that GCC considers warnings: +/// +/// int a, *pint; +/// short *pshort; +/// struct foo *pfoo; +/// +/// pint = pshort; // warning: assignment from incompatible pointer type +/// a = pint; // warning: assignment makes integer from pointer without a cast +/// pint = a; // warning: assignment makes pointer from integer without a cast +/// pint = pfoo; // warning: assignment from incompatible pointer type +/// +/// As a result, the code for dealing with pointers is more complex than the +/// C99 spec dictates. +/// +/// Sets 'Kind' for any result kind except Incompatible. +Sema::AssignConvertType +Sema::CheckAssignmentConstraints(QualType LHSType, ExprResult &RHS, + CastKind &Kind) { + QualType RHSType = RHS.get()->getType(); + QualType OrigLHSType = LHSType; + + // Get canonical types. We're not formatting these types, just comparing + // them. + LHSType = Context.getCanonicalType(LHSType).getUnqualifiedType(); + RHSType = Context.getCanonicalType(RHSType).getUnqualifiedType(); + + + // Common case: no conversion required. + if (LHSType == RHSType) { + Kind = CK_NoOp; + return Compatible; + } + + if (const AtomicType *AtomicTy = dyn_cast<AtomicType>(LHSType)) { + if (AtomicTy->getValueType() == RHSType) { + Kind = CK_NonAtomicToAtomic; + return Compatible; + } + } + + if (const AtomicType *AtomicTy = dyn_cast<AtomicType>(RHSType)) { + if (AtomicTy->getValueType() == LHSType) { + Kind = CK_AtomicToNonAtomic; + return Compatible; + } + } + + + // If the left-hand side is a reference type, then we are in a + // (rare!) case where we've allowed the use of references in C, + // e.g., as a parameter type in a built-in function. In this case, + // just make sure that the type referenced is compatible with the + // right-hand side type. The caller is responsible for adjusting + // LHSType so that the resulting expression does not have reference + // type. + if (const ReferenceType *LHSTypeRef = LHSType->getAs<ReferenceType>()) { + if (Context.typesAreCompatible(LHSTypeRef->getPointeeType(), RHSType)) { + Kind = CK_LValueBitCast; + return Compatible; + } + return Incompatible; + } + + // Allow scalar to ExtVector assignments, and assignments of an ExtVector type + // to the same ExtVector type. + if (LHSType->isExtVectorType()) { + if (RHSType->isExtVectorType()) + return Incompatible; + if (RHSType->isArithmeticType()) { + // CK_VectorSplat does T -> vector T, so first cast to the + // element type. + QualType elType = cast<ExtVectorType>(LHSType)->getElementType(); + if (elType != RHSType) { + Kind = PrepareScalarCast(RHS, elType); + RHS = ImpCastExprToType(RHS.take(), elType, Kind); + } + Kind = CK_VectorSplat; + return Compatible; + } + } + + // Conversions to or from vector type. + if (LHSType->isVectorType() || RHSType->isVectorType()) { + if (LHSType->isVectorType() && RHSType->isVectorType()) { + // Allow assignments of an AltiVec vector type to an equivalent GCC + // vector type and vice versa + if (Context.areCompatibleVectorTypes(LHSType, RHSType)) { + Kind = CK_BitCast; + return Compatible; + } + + // If we are allowing lax vector conversions, and LHS and RHS are both + // vectors, the total size only needs to be the same. This is a bitcast; + // no bits are changed but the result type is different. + if (getLangOpts().LaxVectorConversions && + (Context.getTypeSize(LHSType) == Context.getTypeSize(RHSType))) { + Kind = CK_BitCast; + return IncompatibleVectors; + } + } + return Incompatible; + } + + // Arithmetic conversions. + if (LHSType->isArithmeticType() && RHSType->isArithmeticType() && + !(getLangOpts().CPlusPlus && LHSType->isEnumeralType())) { + Kind = PrepareScalarCast(RHS, LHSType); + return Compatible; + } + + // Conversions to normal pointers. + if (const PointerType *LHSPointer = dyn_cast<PointerType>(LHSType)) { + // U* -> T* + if (isa<PointerType>(RHSType)) { + Kind = CK_BitCast; + return checkPointerTypesForAssignment(*this, LHSType, RHSType); + } + + // int -> T* + if (RHSType->isIntegerType()) { + Kind = CK_IntegralToPointer; // FIXME: null? + return IntToPointer; + } + + // C pointers are not compatible with ObjC object pointers, + // with two exceptions: + if (isa<ObjCObjectPointerType>(RHSType)) { + // - conversions to void* + if (LHSPointer->getPointeeType()->isVoidType()) { + Kind = CK_BitCast; + return Compatible; + } + + // - conversions from 'Class' to the redefinition type + if (RHSType->isObjCClassType() && + Context.hasSameType(LHSType, + Context.getObjCClassRedefinitionType())) { + Kind = CK_BitCast; + return Compatible; + } + + Kind = CK_BitCast; + return IncompatiblePointer; + } + + // U^ -> void* + if (RHSType->getAs<BlockPointerType>()) { + if (LHSPointer->getPointeeType()->isVoidType()) { + Kind = CK_BitCast; + return Compatible; + } + } + + return Incompatible; + } + + // Conversions to block pointers. + if (isa<BlockPointerType>(LHSType)) { + // U^ -> T^ + if (RHSType->isBlockPointerType()) { + Kind = CK_BitCast; + return checkBlockPointerTypesForAssignment(*this, LHSType, RHSType); + } + + // int or null -> T^ + if (RHSType->isIntegerType()) { + Kind = CK_IntegralToPointer; // FIXME: null + return IntToBlockPointer; + } + + // id -> T^ + if (getLangOpts().ObjC1 && RHSType->isObjCIdType()) { + Kind = CK_AnyPointerToBlockPointerCast; + return Compatible; + } + + // void* -> T^ + if (const PointerType *RHSPT = RHSType->getAs<PointerType>()) + if (RHSPT->getPointeeType()->isVoidType()) { + Kind = CK_AnyPointerToBlockPointerCast; + return Compatible; + } + + return Incompatible; + } + + // Conversions to Objective-C pointers. + if (isa<ObjCObjectPointerType>(LHSType)) { + // A* -> B* + if (RHSType->isObjCObjectPointerType()) { + Kind = CK_BitCast; + Sema::AssignConvertType result = + checkObjCPointerTypesForAssignment(*this, LHSType, RHSType); + if (getLangOpts().ObjCAutoRefCount && + result == Compatible && + !CheckObjCARCUnavailableWeakConversion(OrigLHSType, RHSType)) + result = IncompatibleObjCWeakRef; + return result; + } + + // int or null -> A* + if (RHSType->isIntegerType()) { + Kind = CK_IntegralToPointer; // FIXME: null + return IntToPointer; + } + + // In general, C pointers are not compatible with ObjC object pointers, + // with two exceptions: + if (isa<PointerType>(RHSType)) { + Kind = CK_CPointerToObjCPointerCast; + + // - conversions from 'void*' + if (RHSType->isVoidPointerType()) { + return Compatible; + } + + // - conversions to 'Class' from its redefinition type + if (LHSType->isObjCClassType() && + Context.hasSameType(RHSType, + Context.getObjCClassRedefinitionType())) { + return Compatible; + } + + return IncompatiblePointer; + } + + // T^ -> A* + if (RHSType->isBlockPointerType()) { + maybeExtendBlockObject(*this, RHS); + Kind = CK_BlockPointerToObjCPointerCast; + return Compatible; + } + + return Incompatible; + } + + // Conversions from pointers that are not covered by the above. + if (isa<PointerType>(RHSType)) { + // T* -> _Bool + if (LHSType == Context.BoolTy) { + Kind = CK_PointerToBoolean; + return Compatible; + } + + // T* -> int + if (LHSType->isIntegerType()) { + Kind = CK_PointerToIntegral; + return PointerToInt; + } + + return Incompatible; + } + + // Conversions from Objective-C pointers that are not covered by the above. + if (isa<ObjCObjectPointerType>(RHSType)) { + // T* -> _Bool + if (LHSType == Context.BoolTy) { + Kind = CK_PointerToBoolean; + return Compatible; + } + + // T* -> int + if (LHSType->isIntegerType()) { + Kind = CK_PointerToIntegral; + return PointerToInt; + } + + return Incompatible; + } + + // struct A -> struct B + if (isa<TagType>(LHSType) && isa<TagType>(RHSType)) { + if (Context.typesAreCompatible(LHSType, RHSType)) { + Kind = CK_NoOp; + return Compatible; + } + } + + return Incompatible; +} + +/// \brief Constructs a transparent union from an expression that is +/// used to initialize the transparent union. +static void ConstructTransparentUnion(Sema &S, ASTContext &C, + ExprResult &EResult, QualType UnionType, + FieldDecl *Field) { + // Build an initializer list that designates the appropriate member + // of the transparent union. + Expr *E = EResult.take(); + InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), + &E, 1, + SourceLocation()); + Initializer->setType(UnionType); + Initializer->setInitializedFieldInUnion(Field); + + // Build a compound literal constructing a value of the transparent + // union type from this initializer list. + TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); + EResult = S.Owned( + new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, + VK_RValue, Initializer, false)); +} + +Sema::AssignConvertType +Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, + ExprResult &RHS) { + QualType RHSType = RHS.get()->getType(); + + // If the ArgType is a Union type, we want to handle a potential + // transparent_union GCC extension. + const RecordType *UT = ArgType->getAsUnionType(); + if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) + return Incompatible; + + // The field to initialize within the transparent union. + RecordDecl *UD = UT->getDecl(); + FieldDecl *InitField = 0; + // It's compatible if the expression matches any of the fields. + for (RecordDecl::field_iterator it = UD->field_begin(), + itend = UD->field_end(); + it != itend; ++it) { + if (it->getType()->isPointerType()) { + // If the transparent union contains a pointer type, we allow: + // 1) void pointer + // 2) null pointer constant + if (RHSType->isPointerType()) + if (RHSType->castAs<PointerType>()->getPointeeType()->isVoidType()) { + RHS = ImpCastExprToType(RHS.take(), it->getType(), CK_BitCast); + InitField = *it; + break; + } + + if (RHS.get()->isNullPointerConstant(Context, + Expr::NPC_ValueDependentIsNull)) { + RHS = ImpCastExprToType(RHS.take(), it->getType(), + CK_NullToPointer); + InitField = *it; + break; + } + } + + CastKind Kind = CK_Invalid; + if (CheckAssignmentConstraints(it->getType(), RHS, Kind) + == Compatible) { + RHS = ImpCastExprToType(RHS.take(), it->getType(), Kind); + InitField = *it; + break; + } + } + + if (!InitField) + return Incompatible; + + ConstructTransparentUnion(*this, Context, RHS, ArgType, InitField); + return Compatible; +} + +Sema::AssignConvertType +Sema::CheckSingleAssignmentConstraints(QualType LHSType, ExprResult &RHS, + bool Diagnose) { + if (getLangOpts().CPlusPlus) { + if (!LHSType->isRecordType() && !LHSType->isAtomicType()) { + // C++ 5.17p3: If the left operand is not of class type, the + // expression is implicitly converted (C++ 4) to the + // cv-unqualified type of the left operand. + ExprResult Res; + if (Diagnose) { + Res = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), + AA_Assigning); + } else { + ImplicitConversionSequence ICS = + TryImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), + /*SuppressUserConversions=*/false, + /*AllowExplicit=*/false, + /*InOverloadResolution=*/false, + /*CStyle=*/false, + /*AllowObjCWritebackConversion=*/false); + if (ICS.isFailure()) + return Incompatible; + Res = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), + ICS, AA_Assigning); + } + if (Res.isInvalid()) + return Incompatible; + Sema::AssignConvertType result = Compatible; + if (getLangOpts().ObjCAutoRefCount && + !CheckObjCARCUnavailableWeakConversion(LHSType, + RHS.get()->getType())) + result = IncompatibleObjCWeakRef; + RHS = move(Res); + return result; + } + + // FIXME: Currently, we fall through and treat C++ classes like C + // structures. + // FIXME: We also fall through for atomics; not sure what should + // happen there, though. + } + + // C99 6.5.16.1p1: the left operand is a pointer and the right is + // a null pointer constant. + if ((LHSType->isPointerType() || + LHSType->isObjCObjectPointerType() || + LHSType->isBlockPointerType()) + && RHS.get()->isNullPointerConstant(Context, + Expr::NPC_ValueDependentIsNull)) { + RHS = ImpCastExprToType(RHS.take(), LHSType, CK_NullToPointer); + return Compatible; + } + + // This check seems unnatural, however it is necessary to ensure the proper + // conversion of functions/arrays. If the conversion were done for all + // DeclExpr's (created by ActOnIdExpression), it would mess up the unary + // expressions that suppress this implicit conversion (&, sizeof). + // + // Suppress this for references: C++ 8.5.3p5. + if (!LHSType->isReferenceType()) { + RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); + if (RHS.isInvalid()) + return Incompatible; + } + + CastKind Kind = CK_Invalid; + Sema::AssignConvertType result = + CheckAssignmentConstraints(LHSType, RHS, Kind); + + // C99 6.5.16.1p2: The value of the right operand is converted to the + // type of the assignment expression. + // CheckAssignmentConstraints allows the left-hand side to be a reference, + // so that we can use references in built-in functions even in C. + // The getNonReferenceType() call makes sure that the resulting expression + // does not have reference type. + if (result != Incompatible && RHS.get()->getType() != LHSType) + RHS = ImpCastExprToType(RHS.take(), + LHSType.getNonLValueExprType(Context), Kind); + return result; +} + +QualType Sema::InvalidOperands(SourceLocation Loc, ExprResult &LHS, + ExprResult &RHS) { + Diag(Loc, diag::err_typecheck_invalid_operands) + << LHS.get()->getType() << RHS.get()->getType() + << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); + return QualType(); +} + +QualType Sema::CheckVectorOperands(ExprResult &LHS, ExprResult &RHS, + SourceLocation Loc, bool IsCompAssign) { + if (!IsCompAssign) { + LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); + if (LHS.isInvalid()) + return QualType(); + } + RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); + if (RHS.isInvalid()) + return QualType(); + + // For conversion purposes, we ignore any qualifiers. + // For example, "const float" and "float" are equivalent. + QualType LHSType = + Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType(); + QualType RHSType = + Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType(); + + // If the vector types are identical, return. + if (LHSType == RHSType) + return LHSType; + + // Handle the case of equivalent AltiVec and GCC vector types + if (LHSType->isVectorType() && RHSType->isVectorType() && + Context.areCompatibleVectorTypes(LHSType, RHSType)) { + if (LHSType->isExtVectorType()) { + RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); + return LHSType; + } + + if (!IsCompAssign) + LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); + return RHSType; + } + + if (getLangOpts().LaxVectorConversions && + Context.getTypeSize(LHSType) == Context.getTypeSize(RHSType)) { + // If we are allowing lax vector conversions, and LHS and RHS are both + // vectors, the total size only needs to be the same. This is a + // bitcast; no bits are changed but the result type is different. + // FIXME: Should we really be allowing this? + RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); + return LHSType; + } + + // Canonicalize the ExtVector to the LHS, remember if we swapped so we can + // swap back (so that we don't reverse the inputs to a subtract, for instance. + bool swapped = false; + if (RHSType->isExtVectorType() && !IsCompAssign) { + swapped = true; + std::swap(RHS, LHS); + std::swap(RHSType, LHSType); + } + + // Handle the case of an ext vector and scalar. + if (const ExtVectorType *LV = LHSType->getAs<ExtVectorType>()) { + QualType EltTy = LV->getElementType(); + if (EltTy->isIntegralType(Context) && RHSType->isIntegralType(Context)) { + int order = Context.getIntegerTypeOrder(EltTy, RHSType); + if (order > 0) + RHS = ImpCastExprToType(RHS.take(), EltTy, CK_IntegralCast); + if (order >= 0) { + RHS = ImpCastExprToType(RHS.take(), LHSType, CK_VectorSplat); + if (swapped) std::swap(RHS, LHS); + return LHSType; + } + } + if (EltTy->isRealFloatingType() && RHSType->isScalarType() && + RHSType->isRealFloatingType()) { + int order = Context.getFloatingTypeOrder(EltTy, RHSType); + if (order > 0) + RHS = ImpCastExprToType(RHS.take(), EltTy, CK_FloatingCast); + if (order >= 0) { + RHS = ImpCastExprToType(RHS.take(), LHSType, CK_VectorSplat); + if (swapped) std::swap(RHS, LHS); + return LHSType; + } + } + } + + // Vectors of different size or scalar and non-ext-vector are errors. + if (swapped) std::swap(RHS, LHS); + Diag(Loc, diag::err_typecheck_vector_not_convertable) + << LHS.get()->getType() << RHS.get()->getType() + << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); + return QualType(); +} + +// checkArithmeticNull - Detect when a NULL constant is used improperly in an +// expression. These are mainly cases where the null pointer is used as an +// integer instead of a pointer. +static void checkArithmeticNull(Sema &S, ExprResult &LHS, ExprResult &RHS, + SourceLocation Loc, bool IsCompare) { + // The canonical way to check for a GNU null is with isNullPointerConstant, + // but we use a bit of a hack here for speed; this is a relatively + // hot path, and isNullPointerConstant is slow. + bool LHSNull = isa<GNUNullExpr>(LHS.get()->IgnoreParenImpCasts()); + bool RHSNull = isa<GNUNullExpr>(RHS.get()->IgnoreParenImpCasts()); + + QualType NonNullType = LHSNull ? RHS.get()->getType() : LHS.get()->getType(); + + // Avoid analyzing cases where the result will either be invalid (and + // diagnosed as such) or entirely valid and not something to warn about. + if ((!LHSNull && !RHSNull) || NonNullType->isBlockPointerType() || + NonNullType->isMemberPointerType() || NonNullType->isFunctionType()) + return; + + // Comparison operations would not make sense with a null pointer no matter + // what the other expression is. + if (!IsCompare) { + S.Diag(Loc, diag::warn_null_in_arithmetic_operation) + << (LHSNull ? LHS.get()->getSourceRange() : SourceRange()) + << (RHSNull ? RHS.get()->getSourceRange() : SourceRange()); + return; + } + + // The rest of the operations only make sense with a null pointer + // if the other expression is a pointer. + if (LHSNull == RHSNull || NonNullType->isAnyPointerType() || + NonNullType->canDecayToPointerType()) + return; + + S.Diag(Loc, diag::warn_null_in_comparison_operation) + << LHSNull /* LHS is NULL */ << NonNullType + << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); +} + +QualType Sema::CheckMultiplyDivideOperands(ExprResult &LHS, ExprResult &RHS, + SourceLocation Loc, + bool IsCompAssign, bool IsDiv) { + checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); + + if (LHS.get()->getType()->isVectorType() || + RHS.get()->getType()->isVectorType()) + return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); + + QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign); + if (LHS.isInvalid() || RHS.isInvalid()) + return QualType(); + + + if (!LHS.get()->getType()->isArithmeticType() || + !RHS.get()->getType()->isArithmeticType()) { + if (IsCompAssign && + LHS.get()->getType()->isAtomicType() && + RHS.get()->getType()->isArithmeticType()) + return compType; + return InvalidOperands(Loc, LHS, RHS); + } + + // Check for division by zero. + if (IsDiv && + RHS.get()->isNullPointerConstant(Context, + Expr::NPC_ValueDependentIsNotNull)) + DiagRuntimeBehavior(Loc, RHS.get(), PDiag(diag::warn_division_by_zero) + << RHS.get()->getSourceRange()); + + return compType; +} + +QualType Sema::CheckRemainderOperands( + ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) { + checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); + + if (LHS.get()->getType()->isVectorType() || + RHS.get()->getType()->isVectorType()) { + if (LHS.get()->getType()->hasIntegerRepresentation() && + RHS.get()->getType()->hasIntegerRepresentation()) + return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); + return InvalidOperands(Loc, LHS, RHS); + } + + QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign); + if (LHS.isInvalid() || RHS.isInvalid()) + return QualType(); + + if (!LHS.get()->getType()->isIntegerType() || + !RHS.get()->getType()->isIntegerType()) + return InvalidOperands(Loc, LHS, RHS); + + // Check for remainder by zero. + if (RHS.get()->isNullPointerConstant(Context, + Expr::NPC_ValueDependentIsNotNull)) + DiagRuntimeBehavior(Loc, RHS.get(), PDiag(diag::warn_remainder_by_zero) + << RHS.get()->getSourceRange()); + + return compType; +} + +/// \brief Diagnose invalid arithmetic on two void pointers. +static void diagnoseArithmeticOnTwoVoidPointers(Sema &S, SourceLocation Loc, + Expr *LHSExpr, Expr *RHSExpr) { + S.Diag(Loc, S.getLangOpts().CPlusPlus + ? diag::err_typecheck_pointer_arith_void_type + : diag::ext_gnu_void_ptr) + << 1 /* two pointers */ << LHSExpr->getSourceRange() + << RHSExpr->getSourceRange(); +} + +/// \brief Diagnose invalid arithmetic on a void pointer. +static void diagnoseArithmeticOnVoidPointer(Sema &S, SourceLocation Loc, + Expr *Pointer) { + S.Diag(Loc, S.getLangOpts().CPlusPlus + ? diag::err_typecheck_pointer_arith_void_type + : diag::ext_gnu_void_ptr) + << 0 /* one pointer */ << Pointer->getSourceRange(); +} + +/// \brief Diagnose invalid arithmetic on two function pointers. +static void diagnoseArithmeticOnTwoFunctionPointers(Sema &S, SourceLocation Loc, + Expr *LHS, Expr *RHS) { + assert(LHS->getType()->isAnyPointerType()); + assert(RHS->getType()->isAnyPointerType()); + S.Diag(Loc, S.getLangOpts().CPlusPlus + ? diag::err_typecheck_pointer_arith_function_type + : diag::ext_gnu_ptr_func_arith) + << 1 /* two pointers */ << LHS->getType()->getPointeeType() + // We only show the second type if it differs from the first. + << (unsigned)!S.Context.hasSameUnqualifiedType(LHS->getType(), + RHS->getType()) + << RHS->getType()->getPointeeType() + << LHS->getSourceRange() << RHS->getSourceRange(); +} + +/// \brief Diagnose invalid arithmetic on a function pointer. +static void diagnoseArithmeticOnFunctionPointer(Sema &S, SourceLocation Loc, + Expr *Pointer) { + assert(Pointer->getType()->isAnyPointerType()); + S.Diag(Loc, S.getLangOpts().CPlusPlus + ? diag::err_typecheck_pointer_arith_function_type + : diag::ext_gnu_ptr_func_arith) + << 0 /* one pointer */ << Pointer->getType()->getPointeeType() + << 0 /* one pointer, so only one type */ + << Pointer->getSourceRange(); +} + +/// \brief Emit error if Operand is incomplete pointer type +/// +/// \returns True if pointer has incomplete type +static bool checkArithmeticIncompletePointerType(Sema &S, SourceLocation Loc, + Expr *Operand) { + if ((Operand->getType()->isPointerType() && + !Operand->getType()->isDependentType()) || + Operand->getType()->isObjCObjectPointerType()) { + QualType PointeeTy = Operand->getType()->getPointeeType(); + if (S.RequireCompleteType( + Loc, PointeeTy, + S.PDiag(diag::err_typecheck_arithmetic_incomplete_type) + << PointeeTy << Operand->getSourceRange())) + return true; + } + return false; +} + +/// \brief Check the validity of an arithmetic pointer operand. +/// +/// If the operand has pointer type, this code will check for pointer types +/// which are invalid in arithmetic operations. These will be diagnosed +/// appropriately, including whether or not the use is supported as an +/// extension. +/// +/// \returns True when the operand is valid to use (even if as an extension). +static bool checkArithmeticOpPointerOperand(Sema &S, SourceLocation Loc, + Expr *Operand) { + if (!Operand->getType()->isAnyPointerType()) return true; + + QualType PointeeTy = Operand->getType()->getPointeeType(); + if (PointeeTy->isVoidType()) { + diagnoseArithmeticOnVoidPointer(S, Loc, Operand); + return !S.getLangOpts().CPlusPlus; + } + if (PointeeTy->isFunctionType()) { + diagnoseArithmeticOnFunctionPointer(S, Loc, Operand); + return !S.getLangOpts().CPlusPlus; + } + + if (checkArithmeticIncompletePointerType(S, Loc, Operand)) return false; + + return true; +} + +/// \brief Check the validity of a binary arithmetic operation w.r.t. pointer +/// operands. +/// +/// This routine will diagnose any invalid arithmetic on pointer operands much +/// like \see checkArithmeticOpPointerOperand. However, it has special logic +/// for emitting a single diagnostic even for operations where both LHS and RHS +/// are (potentially problematic) pointers. +/// +/// \returns True when the operand is valid to use (even if as an extension). +static bool checkArithmeticBinOpPointerOperands(Sema &S, SourceLocation Loc, + Expr *LHSExpr, Expr *RHSExpr) { + bool isLHSPointer = LHSExpr->getType()->isAnyPointerType(); + bool isRHSPointer = RHSExpr->getType()->isAnyPointerType(); + if (!isLHSPointer && !isRHSPointer) return true; + + QualType LHSPointeeTy, RHSPointeeTy; + if (isLHSPointer) LHSPointeeTy = LHSExpr->getType()->getPointeeType(); + if (isRHSPointer) RHSPointeeTy = RHSExpr->getType()->getPointeeType(); + + // Check for arithmetic on pointers to incomplete types. + bool isLHSVoidPtr = isLHSPointer && LHSPointeeTy->isVoidType(); + bool isRHSVoidPtr = isRHSPointer && RHSPointeeTy->isVoidType(); + if (isLHSVoidPtr || isRHSVoidPtr) { + if (!isRHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, LHSExpr); + else if (!isLHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, RHSExpr); + else diagnoseArithmeticOnTwoVoidPointers(S, Loc, LHSExpr, RHSExpr); + + return !S.getLangOpts().CPlusPlus; + } + + bool isLHSFuncPtr = isLHSPointer && LHSPointeeTy->isFunctionType(); + bool isRHSFuncPtr = isRHSPointer && RHSPointeeTy->isFunctionType(); + if (isLHSFuncPtr || isRHSFuncPtr) { + if (!isRHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, LHSExpr); + else if (!isLHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, + RHSExpr); + else diagnoseArithmeticOnTwoFunctionPointers(S, Loc, LHSExpr, RHSExpr); + + return !S.getLangOpts().CPlusPlus; + } + + if (checkArithmeticIncompletePointerType(S, Loc, LHSExpr)) return false; + if (checkArithmeticIncompletePointerType(S, Loc, RHSExpr)) return false; + + return true; +} + +/// \brief Check bad cases where we step over interface counts. +static bool checkArithmethicPointerOnNonFragileABI(Sema &S, + SourceLocation OpLoc, + Expr *Op) { + assert(Op->getType()->isAnyPointerType()); + QualType PointeeTy = Op->getType()->getPointeeType(); + if (!PointeeTy->isObjCObjectType() || !S.LangOpts.ObjCNonFragileABI) + return true; + + S.Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) + << PointeeTy << Op->getSourceRange(); + return false; +} + +/// diagnoseStringPlusInt - Emit a warning when adding an integer to a string +/// literal. +static void diagnoseStringPlusInt(Sema &Self, SourceLocation OpLoc, + Expr *LHSExpr, Expr *RHSExpr) { + StringLiteral* StrExpr = dyn_cast<StringLiteral>(LHSExpr->IgnoreImpCasts()); + Expr* IndexExpr = RHSExpr; + if (!StrExpr) { + StrExpr = dyn_cast<StringLiteral>(RHSExpr->IgnoreImpCasts()); + IndexExpr = LHSExpr; + } + + bool IsStringPlusInt = StrExpr && + IndexExpr->getType()->isIntegralOrUnscopedEnumerationType(); + if (!IsStringPlusInt) + return; + + llvm::APSInt index; + if (IndexExpr->EvaluateAsInt(index, Self.getASTContext())) { + unsigned StrLenWithNull = StrExpr->getLength() + 1; + if (index.isNonNegative() && + index <= llvm::APSInt(llvm::APInt(index.getBitWidth(), StrLenWithNull), + index.isUnsigned())) + return; + } + + SourceRange DiagRange(LHSExpr->getLocStart(), RHSExpr->getLocEnd()); + Self.Diag(OpLoc, diag::warn_string_plus_int) + << DiagRange << IndexExpr->IgnoreImpCasts()->getType(); + + // Only print a fixit for "str" + int, not for int + "str". + if (IndexExpr == RHSExpr) { + SourceLocation EndLoc = Self.PP.getLocForEndOfToken(RHSExpr->getLocEnd()); + Self.Diag(OpLoc, diag::note_string_plus_int_silence) + << FixItHint::CreateInsertion(LHSExpr->getLocStart(), "&") + << FixItHint::CreateReplacement(SourceRange(OpLoc), "[") + << FixItHint::CreateInsertion(EndLoc, "]"); + } else + Self.Diag(OpLoc, diag::note_string_plus_int_silence); +} + +/// \brief Emit error when two pointers are incompatible. +static void diagnosePointerIncompatibility(Sema &S, SourceLocation Loc, + Expr *LHSExpr, Expr *RHSExpr) { + assert(LHSExpr->getType()->isAnyPointerType()); + assert(RHSExpr->getType()->isAnyPointerType()); + S.Diag(Loc, diag::err_typecheck_sub_ptr_compatible) + << LHSExpr->getType() << RHSExpr->getType() << LHSExpr->getSourceRange() + << RHSExpr->getSourceRange(); +} + +QualType Sema::CheckAdditionOperands( // C99 6.5.6 + ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, unsigned Opc, + QualType* CompLHSTy) { + checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); + + if (LHS.get()->getType()->isVectorType() || + RHS.get()->getType()->isVectorType()) { + QualType compType = CheckVectorOperands(LHS, RHS, Loc, CompLHSTy); + if (CompLHSTy) *CompLHSTy = compType; + return compType; + } + + QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy); + if (LHS.isInvalid() || RHS.isInvalid()) + return QualType(); + + // Diagnose "string literal" '+' int. + if (Opc == BO_Add) + diagnoseStringPlusInt(*this, Loc, LHS.get(), RHS.get()); + + // handle the common case first (both operands are arithmetic). + if (LHS.get()->getType()->isArithmeticType() && + RHS.get()->getType()->isArithmeticType()) { + if (CompLHSTy) *CompLHSTy = compType; + return compType; + } + + if (LHS.get()->getType()->isAtomicType() && + RHS.get()->getType()->isArithmeticType()) { + *CompLHSTy = LHS.get()->getType(); + return compType; + } + + // Put any potential pointer into PExp + Expr* PExp = LHS.get(), *IExp = RHS.get(); + if (IExp->getType()->isAnyPointerType()) + std::swap(PExp, IExp); + + if (!PExp->getType()->isAnyPointerType()) + return InvalidOperands(Loc, LHS, RHS); + + if (!IExp->getType()->isIntegerType()) + return InvalidOperands(Loc, LHS, RHS); + + if (!checkArithmeticOpPointerOperand(*this, Loc, PExp)) + return QualType(); + + // Diagnose bad cases where we step over interface counts. + if (!checkArithmethicPointerOnNonFragileABI(*this, Loc, PExp)) + return QualType(); + + // Check array bounds for pointer arithemtic + CheckArrayAccess(PExp, IExp); + + if (CompLHSTy) { + QualType LHSTy = Context.isPromotableBitField(LHS.get()); + if (LHSTy.isNull()) { + LHSTy = LHS.get()->getType(); + if (LHSTy->isPromotableIntegerType()) + LHSTy = Context.getPromotedIntegerType(LHSTy); + } + *CompLHSTy = LHSTy; + } + + return PExp->getType(); +} + +// C99 6.5.6 +QualType Sema::CheckSubtractionOperands(ExprResult &LHS, ExprResult &RHS, + SourceLocation Loc, + QualType* CompLHSTy) { + checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); + + if (LHS.get()->getType()->isVectorType() || + RHS.get()->getType()->isVectorType()) { + QualType compType = CheckVectorOperands(LHS, RHS, Loc, CompLHSTy); + if (CompLHSTy) *CompLHSTy = compType; + return compType; + } + + QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy); + if (LHS.isInvalid() || RHS.isInvalid()) + return QualType(); + + // Enforce type constraints: C99 6.5.6p3. + + // Handle the common case first (both operands are arithmetic). + if (LHS.get()->getType()->isArithmeticType() && + RHS.get()->getType()->isArithmeticType()) { + if (CompLHSTy) *CompLHSTy = compType; + return compType; + } + + if (LHS.get()->getType()->isAtomicType() && + RHS.get()->getType()->isArithmeticType()) { + *CompLHSTy = LHS.get()->getType(); + return compType; + } + + // Either ptr - int or ptr - ptr. + if (LHS.get()->getType()->isAnyPointerType()) { + QualType lpointee = LHS.get()->getType()->getPointeeType(); + + // Diagnose bad cases where we step over interface counts. + if (!checkArithmethicPointerOnNonFragileABI(*this, Loc, LHS.get())) + return QualType(); + + // The result type of a pointer-int computation is the pointer type. + if (RHS.get()->getType()->isIntegerType()) { + if (!checkArithmeticOpPointerOperand(*this, Loc, LHS.get())) + return QualType(); + + // Check array bounds for pointer arithemtic + CheckArrayAccess(LHS.get(), RHS.get(), /*ArraySubscriptExpr*/0, + /*AllowOnePastEnd*/true, /*IndexNegated*/true); + + if (CompLHSTy) *CompLHSTy = LHS.get()->getType(); + return LHS.get()->getType(); + } + + // Handle pointer-pointer subtractions. + if (const PointerType *RHSPTy + = RHS.get()->getType()->getAs<PointerType>()) { + QualType rpointee = RHSPTy->getPointeeType(); + + if (getLangOpts().CPlusPlus) { + // Pointee types must be the same: C++ [expr.add] + if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { + diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get()); + } + } else { + // Pointee types must be compatible C99 6.5.6p3 + if (!Context.typesAreCompatible( + Context.getCanonicalType(lpointee).getUnqualifiedType(), + Context.getCanonicalType(rpointee).getUnqualifiedType())) { + diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get()); + return QualType(); + } + } + + if (!checkArithmeticBinOpPointerOperands(*this, Loc, + LHS.get(), RHS.get())) + return QualType(); + + if (CompLHSTy) *CompLHSTy = LHS.get()->getType(); + return Context.getPointerDiffType(); + } + } + + return InvalidOperands(Loc, LHS, RHS); +} + +static bool isScopedEnumerationType(QualType T) { + if (const EnumType *ET = dyn_cast<EnumType>(T)) + return ET->getDecl()->isScoped(); + return false; +} + +static void DiagnoseBadShiftValues(Sema& S, ExprResult &LHS, ExprResult &RHS, + SourceLocation Loc, unsigned Opc, + QualType LHSType) { + llvm::APSInt Right; + // Check right/shifter operand + if (RHS.get()->isValueDependent() || + !RHS.get()->isIntegerConstantExpr(Right, S.Context)) + return; + + if (Right.isNegative()) { + S.DiagRuntimeBehavior(Loc, RHS.get(), + S.PDiag(diag::warn_shift_negative) + << RHS.get()->getSourceRange()); + return; + } + llvm::APInt LeftBits(Right.getBitWidth(), + S.Context.getTypeSize(LHS.get()->getType())); + if (Right.uge(LeftBits)) { + S.DiagRuntimeBehavior(Loc, RHS.get(), + S.PDiag(diag::warn_shift_gt_typewidth) + << RHS.get()->getSourceRange()); + return; + } + if (Opc != BO_Shl) + return; + + // When left shifting an ICE which is signed, we can check for overflow which + // according to C++ has undefined behavior ([expr.shift] 5.8/2). Unsigned + // integers have defined behavior modulo one more than the maximum value + // representable in the result type, so never warn for those. + llvm::APSInt Left; + if (LHS.get()->isValueDependent() || + !LHS.get()->isIntegerConstantExpr(Left, S.Context) || + LHSType->hasUnsignedIntegerRepresentation()) + return; + llvm::APInt ResultBits = + static_cast<llvm::APInt&>(Right) + Left.getMinSignedBits(); + if (LeftBits.uge(ResultBits)) + return; + llvm::APSInt Result = Left.extend(ResultBits.getLimitedValue()); + Result = Result.shl(Right); + + // Print the bit representation of the signed integer as an unsigned + // hexadecimal number. + SmallString<40> HexResult; + Result.toString(HexResult, 16, /*Signed =*/false, /*Literal =*/true); + + // If we are only missing a sign bit, this is less likely to result in actual + // bugs -- if the result is cast back to an unsigned type, it will have the + // expected value. Thus we place this behind a different warning that can be + // turned off separately if needed. + if (LeftBits == ResultBits - 1) { + S.Diag(Loc, diag::warn_shift_result_sets_sign_bit) + << HexResult.str() << LHSType + << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); + return; + } + + S.Diag(Loc, diag::warn_shift_result_gt_typewidth) + << HexResult.str() << Result.getMinSignedBits() << LHSType + << Left.getBitWidth() << LHS.get()->getSourceRange() + << RHS.get()->getSourceRange(); +} + +// C99 6.5.7 +QualType Sema::CheckShiftOperands(ExprResult &LHS, ExprResult &RHS, + SourceLocation Loc, unsigned Opc, + bool IsCompAssign) { + checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); + + // C99 6.5.7p2: Each of the operands shall have integer type. + if (!LHS.get()->getType()->hasIntegerRepresentation() || + !RHS.get()->getType()->hasIntegerRepresentation()) + return InvalidOperands(Loc, LHS, RHS); + + // C++0x: Don't allow scoped enums. FIXME: Use something better than + // hasIntegerRepresentation() above instead of this. + if (isScopedEnumerationType(LHS.get()->getType()) || + isScopedEnumerationType(RHS.get()->getType())) { + return InvalidOperands(Loc, LHS, RHS); + } + + // Vector shifts promote their scalar inputs to vector type. + if (LHS.get()->getType()->isVectorType() || + RHS.get()->getType()->isVectorType()) + return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); + + // Shifts don't perform usual arithmetic conversions, they just do integer + // promotions on each operand. C99 6.5.7p3 + + // For the LHS, do usual unary conversions, but then reset them away + // if this is a compound assignment. + ExprResult OldLHS = LHS; + LHS = UsualUnaryConversions(LHS.take()); + if (LHS.isInvalid()) + return QualType(); + QualType LHSType = LHS.get()->getType(); + if (IsCompAssign) LHS = OldLHS; + + // The RHS is simpler. + RHS = UsualUnaryConversions(RHS.take()); + if (RHS.isInvalid()) + return QualType(); + + // Sanity-check shift operands + DiagnoseBadShiftValues(*this, LHS, RHS, Loc, Opc, LHSType); + + // "The type of the result is that of the promoted left operand." + return LHSType; +} + +static bool IsWithinTemplateSpecialization(Decl *D) { + if (DeclContext *DC = D->getDeclContext()) { + if (isa<ClassTemplateSpecializationDecl>(DC)) + return true; + if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) + return FD->isFunctionTemplateSpecialization(); + } + return false; +} + +/// If two different enums are compared, raise a warning. +static void checkEnumComparison(Sema &S, SourceLocation Loc, ExprResult &LHS, + ExprResult &RHS) { + QualType LHSStrippedType = LHS.get()->IgnoreParenImpCasts()->getType(); + QualType RHSStrippedType = RHS.get()->IgnoreParenImpCasts()->getType(); + + const EnumType *LHSEnumType = LHSStrippedType->getAs<EnumType>(); + if (!LHSEnumType) + return; + const EnumType *RHSEnumType = RHSStrippedType->getAs<EnumType>(); + if (!RHSEnumType) + return; + + // Ignore anonymous enums. + if (!LHSEnumType->getDecl()->getIdentifier()) + return; + if (!RHSEnumType->getDecl()->getIdentifier()) + return; + + if (S.Context.hasSameUnqualifiedType(LHSStrippedType, RHSStrippedType)) + return; + + S.Diag(Loc, diag::warn_comparison_of_mixed_enum_types) + << LHSStrippedType << RHSStrippedType + << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); +} + +/// \brief Diagnose bad pointer comparisons. +static void diagnoseDistinctPointerComparison(Sema &S, SourceLocation Loc, + ExprResult &LHS, ExprResult &RHS, + bool IsError) { + S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_distinct_pointers + : diag::ext_typecheck_comparison_of_distinct_pointers) + << LHS.get()->getType() << RHS.get()->getType() + << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); +} + +/// \brief Returns false if the pointers are converted to a composite type, +/// true otherwise. +static bool convertPointersToCompositeType(Sema &S, SourceLocation Loc, + ExprResult &LHS, ExprResult &RHS) { + // C++ [expr.rel]p2: + // [...] Pointer conversions (4.10) and qualification + // conversions (4.4) are performed on pointer operands (or on + // a pointer operand and a null pointer constant) to bring + // them to their composite pointer type. [...] + // + // C++ [expr.eq]p1 uses the same notion for (in)equality + // comparisons of pointers. + + // C++ [expr.eq]p2: + // In addition, pointers to members can be compared, or a pointer to + // member and a null pointer constant. Pointer to member conversions + // (4.11) and qualification conversions (4.4) are performed to bring + // them to a common type. If one operand is a null pointer constant, + // the common type is the type of the other operand. Otherwise, the + // common type is a pointer to member type similar (4.4) to the type + // of one of the operands, with a cv-qualification signature (4.4) + // that is the union of the cv-qualification signatures of the operand + // types. + + QualType LHSType = LHS.get()->getType(); + QualType RHSType = RHS.get()->getType(); + assert((LHSType->isPointerType() && RHSType->isPointerType()) || + (LHSType->isMemberPointerType() && RHSType->isMemberPointerType())); + + bool NonStandardCompositeType = false; + bool *BoolPtr = S.isSFINAEContext() ? 0 : &NonStandardCompositeType; + QualType T = S.FindCompositePointerType(Loc, LHS, RHS, BoolPtr); + if (T.isNull()) { + diagnoseDistinctPointerComparison(S, Loc, LHS, RHS, /*isError*/true); + return true; + } + + if (NonStandardCompositeType) + S.Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) + << LHSType << RHSType << T << LHS.get()->getSourceRange() + << RHS.get()->getSourceRange(); + + LHS = S.ImpCastExprToType(LHS.take(), T, CK_BitCast); + RHS = S.ImpCastExprToType(RHS.take(), T, CK_BitCast); + return false; +} + +static void diagnoseFunctionPointerToVoidComparison(Sema &S, SourceLocation Loc, + ExprResult &LHS, + ExprResult &RHS, + bool IsError) { + S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_fptr_to_void + : diag::ext_typecheck_comparison_of_fptr_to_void) + << LHS.get()->getType() << RHS.get()->getType() + << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); +} + +// C99 6.5.8, C++ [expr.rel] +QualType Sema::CheckCompareOperands(ExprResult &LHS, ExprResult &RHS, + SourceLocation Loc, unsigned OpaqueOpc, + bool IsRelational) { + checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/true); + + BinaryOperatorKind Opc = (BinaryOperatorKind) OpaqueOpc; + + // Handle vector comparisons separately. + if (LHS.get()->getType()->isVectorType() || + RHS.get()->getType()->isVectorType()) + return CheckVectorCompareOperands(LHS, RHS, Loc, IsRelational); + + QualType LHSType = LHS.get()->getType(); + QualType RHSType = RHS.get()->getType(); + + Expr *LHSStripped = LHS.get()->IgnoreParenImpCasts(); + Expr *RHSStripped = RHS.get()->IgnoreParenImpCasts(); + + checkEnumComparison(*this, Loc, LHS, RHS); + + if (!LHSType->hasFloatingRepresentation() && + !(LHSType->isBlockPointerType() && IsRelational) && + !LHS.get()->getLocStart().isMacroID() && + !RHS.get()->getLocStart().isMacroID()) { + // For non-floating point types, check for self-comparisons of the form + // x == x, x != x, x < x, etc. These always evaluate to a constant, and + // often indicate logic errors in the program. + // + // NOTE: Don't warn about comparison expressions resulting from macro + // expansion. Also don't warn about comparisons which are only self + // comparisons within a template specialization. The warnings should catch + // obvious cases in the definition of the template anyways. The idea is to + // warn when the typed comparison operator will always evaluate to the same + // result. + if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) { + if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) { + if (DRL->getDecl() == DRR->getDecl() && + !IsWithinTemplateSpecialization(DRL->getDecl())) { + DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) + << 0 // self- + << (Opc == BO_EQ + || Opc == BO_LE + || Opc == BO_GE)); + } else if (LHSType->isArrayType() && RHSType->isArrayType() && + !DRL->getDecl()->getType()->isReferenceType() && + !DRR->getDecl()->getType()->isReferenceType()) { + // what is it always going to eval to? + char always_evals_to; + switch(Opc) { + case BO_EQ: // e.g. array1 == array2 + always_evals_to = 0; // false + break; + case BO_NE: // e.g. array1 != array2 + always_evals_to = 1; // true + break; + default: + // best we can say is 'a constant' + always_evals_to = 2; // e.g. array1 <= array2 + break; + } + DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) + << 1 // array + << always_evals_to); + } + } + } + + if (isa<CastExpr>(LHSStripped)) + LHSStripped = LHSStripped->IgnoreParenCasts(); + if (isa<CastExpr>(RHSStripped)) + RHSStripped = RHSStripped->IgnoreParenCasts(); + + // Warn about comparisons against a string constant (unless the other + // operand is null), the user probably wants strcmp. + Expr *literalString = 0; + Expr *literalStringStripped = 0; + if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && + !RHSStripped->isNullPointerConstant(Context, + Expr::NPC_ValueDependentIsNull)) { + literalString = LHS.get(); + literalStringStripped = LHSStripped; + } else if ((isa<StringLiteral>(RHSStripped) || + isa<ObjCEncodeExpr>(RHSStripped)) && + !LHSStripped->isNullPointerConstant(Context, + Expr::NPC_ValueDependentIsNull)) { + literalString = RHS.get(); + literalStringStripped = RHSStripped; + } + + if (literalString) { + std::string resultComparison; + switch (Opc) { + case BO_LT: resultComparison = ") < 0"; break; + case BO_GT: resultComparison = ") > 0"; break; + case BO_LE: resultComparison = ") <= 0"; break; + case BO_GE: resultComparison = ") >= 0"; break; + case BO_EQ: resultComparison = ") == 0"; break; + case BO_NE: resultComparison = ") != 0"; break; + default: llvm_unreachable("Invalid comparison operator"); + } + + DiagRuntimeBehavior(Loc, 0, + PDiag(diag::warn_stringcompare) + << isa<ObjCEncodeExpr>(literalStringStripped) + << literalString->getSourceRange()); + } + } + + // C99 6.5.8p3 / C99 6.5.9p4 + if (LHS.get()->getType()->isArithmeticType() && + RHS.get()->getType()->isArithmeticType()) { + UsualArithmeticConversions(LHS, RHS); + if (LHS.isInvalid() || RHS.isInvalid()) + return QualType(); + } + else { + LHS = UsualUnaryConversions(LHS.take()); + if (LHS.isInvalid()) + return QualType(); + + RHS = UsualUnaryConversions(RHS.take()); + if (RHS.isInvalid()) + return QualType(); + } + + LHSType = LHS.get()->getType(); + RHSType = RHS.get()->getType(); + + // The result of comparisons is 'bool' in C++, 'int' in C. + QualType ResultTy = Context.getLogicalOperationType(); + + if (IsRelational) { + if (LHSType->isRealType() && RHSType->isRealType()) + return ResultTy; + } else { + // Check for comparisons of floating point operands using != and ==. + if (LHSType->hasFloatingRepresentation()) + CheckFloatComparison(Loc, LHS.get(), RHS.get()); + + if (LHSType->isArithmeticType() && RHSType->isArithmeticType()) + return ResultTy; + } + + bool LHSIsNull = LHS.get()->isNullPointerConstant(Context, + Expr::NPC_ValueDependentIsNull); + bool RHSIsNull = RHS.get()->isNullPointerConstant(Context, + Expr::NPC_ValueDependentIsNull); + + // All of the following pointer-related warnings are GCC extensions, except + // when handling null pointer constants. + if (LHSType->isPointerType() && RHSType->isPointerType()) { // C99 6.5.8p2 + QualType LCanPointeeTy = + LHSType->castAs<PointerType>()->getPointeeType().getCanonicalType(); + QualType RCanPointeeTy = + RHSType->castAs<PointerType>()->getPointeeType().getCanonicalType(); + + if (getLangOpts().CPlusPlus) { + if (LCanPointeeTy == RCanPointeeTy) + return ResultTy; + if (!IsRelational && + (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { + // Valid unless comparison between non-null pointer and function pointer + // This is a gcc extension compatibility comparison. + // In a SFINAE context, we treat this as a hard error to maintain + // conformance with the C++ standard. + if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) + && !LHSIsNull && !RHSIsNull) { + diagnoseFunctionPointerToVoidComparison( + *this, Loc, LHS, RHS, /*isError*/ isSFINAEContext()); + + if (isSFINAEContext()) + return QualType(); + + RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); + return ResultTy; + } + } + + if (convertPointersToCompositeType(*this, Loc, LHS, RHS)) + return QualType(); + else + return ResultTy; + } + // C99 6.5.9p2 and C99 6.5.8p2 + if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), + RCanPointeeTy.getUnqualifiedType())) { + // Valid unless a relational comparison of function pointers + if (IsRelational && LCanPointeeTy->isFunctionType()) { + Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) + << LHSType << RHSType << LHS.get()->getSourceRange() + << RHS.get()->getSourceRange(); + } + } else if (!IsRelational && + (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { + // Valid unless comparison between non-null pointer and function pointer + if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) + && !LHSIsNull && !RHSIsNull) + diagnoseFunctionPointerToVoidComparison(*this, Loc, LHS, RHS, + /*isError*/false); + } else { + // Invalid + diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, /*isError*/false); + } + if (LCanPointeeTy != RCanPointeeTy) { + if (LHSIsNull && !RHSIsNull) + LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); + else + RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); + } + return ResultTy; + } + + if (getLangOpts().CPlusPlus) { + // Comparison of nullptr_t with itself. + if (LHSType->isNullPtrType() && RHSType->isNullPtrType()) + return ResultTy; + + // Comparison of pointers with null pointer constants and equality + // comparisons of member pointers to null pointer constants. + if (RHSIsNull && + ((LHSType->isAnyPointerType() || LHSType->isNullPtrType()) || + (!IsRelational && + (LHSType->isMemberPointerType() || LHSType->isBlockPointerType())))) { + RHS = ImpCastExprToType(RHS.take(), LHSType, + LHSType->isMemberPointerType() + ? CK_NullToMemberPointer + : CK_NullToPointer); + return ResultTy; + } + if (LHSIsNull && + ((RHSType->isAnyPointerType() || RHSType->isNullPtrType()) || + (!IsRelational && + (RHSType->isMemberPointerType() || RHSType->isBlockPointerType())))) { + LHS = ImpCastExprToType(LHS.take(), RHSType, + RHSType->isMemberPointerType() + ? CK_NullToMemberPointer + : CK_NullToPointer); + return ResultTy; + } + + // Comparison of member pointers. + if (!IsRelational && + LHSType->isMemberPointerType() && RHSType->isMemberPointerType()) { + if (convertPointersToCompositeType(*this, Loc, LHS, RHS)) + return QualType(); + else + return ResultTy; + } + + // Handle scoped enumeration types specifically, since they don't promote + // to integers. + if (LHS.get()->getType()->isEnumeralType() && + Context.hasSameUnqualifiedType(LHS.get()->getType(), + RHS.get()->getType())) + return ResultTy; + } + + // Handle block pointer types. + if (!IsRelational && LHSType->isBlockPointerType() && + RHSType->isBlockPointerType()) { + QualType lpointee = LHSType->castAs<BlockPointerType>()->getPointeeType(); + QualType rpointee = RHSType->castAs<BlockPointerType>()->getPointeeType(); + + if (!LHSIsNull && !RHSIsNull && + !Context.typesAreCompatible(lpointee, rpointee)) { + Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) + << LHSType << RHSType << LHS.get()->getSourceRange() + << RHS.get()->getSourceRange(); + } + RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); + return ResultTy; + } + + // Allow block pointers to be compared with null pointer constants. + if (!IsRelational + && ((LHSType->isBlockPointerType() && RHSType->isPointerType()) + || (LHSType->isPointerType() && RHSType->isBlockPointerType()))) { + if (!LHSIsNull && !RHSIsNull) { + if (!((RHSType->isPointerType() && RHSType->castAs<PointerType>() + ->getPointeeType()->isVoidType()) + || (LHSType->isPointerType() && LHSType->castAs<PointerType>() + ->getPointeeType()->isVoidType()))) + Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) + << LHSType << RHSType << LHS.get()->getSourceRange() + << RHS.get()->getSourceRange(); + } + if (LHSIsNull && !RHSIsNull) + LHS = ImpCastExprToType(LHS.take(), RHSType, + RHSType->isPointerType() ? CK_BitCast + : CK_AnyPointerToBlockPointerCast); + else + RHS = ImpCastExprToType(RHS.take(), LHSType, + LHSType->isPointerType() ? CK_BitCast + : CK_AnyPointerToBlockPointerCast); + return ResultTy; + } + + if (LHSType->isObjCObjectPointerType() || + RHSType->isObjCObjectPointerType()) { + const PointerType *LPT = LHSType->getAs<PointerType>(); + const PointerType *RPT = RHSType->getAs<PointerType>(); + if (LPT || RPT) { + bool LPtrToVoid = LPT ? LPT->getPointeeType()->isVoidType() : false; + bool RPtrToVoid = RPT ? RPT->getPointeeType()->isVoidType() : false; + + if (!LPtrToVoid && !RPtrToVoid && + !Context.typesAreCompatible(LHSType, RHSType)) { + diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, + /*isError*/false); + } + if (LHSIsNull && !RHSIsNull) + LHS = ImpCastExprToType(LHS.take(), RHSType, + RPT ? CK_BitCast :CK_CPointerToObjCPointerCast); + else + RHS = ImpCastExprToType(RHS.take(), LHSType, + LPT ? CK_BitCast :CK_CPointerToObjCPointerCast); + return ResultTy; + } + if (LHSType->isObjCObjectPointerType() && + RHSType->isObjCObjectPointerType()) { + if (!Context.areComparableObjCPointerTypes(LHSType, RHSType)) + diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, + /*isError*/false); + if (LHSIsNull && !RHSIsNull) + LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); + else + RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); + return ResultTy; + } + } + if ((LHSType->isAnyPointerType() && RHSType->isIntegerType()) || + (LHSType->isIntegerType() && RHSType->isAnyPointerType())) { + unsigned DiagID = 0; + bool isError = false; + if ((LHSIsNull && LHSType->isIntegerType()) || + (RHSIsNull && RHSType->isIntegerType())) { + if (IsRelational && !getLangOpts().CPlusPlus) + DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; + } else if (IsRelational && !getLangOpts().CPlusPlus) + DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; + else if (getLangOpts().CPlusPlus) { + DiagID = diag::err_typecheck_comparison_of_pointer_integer; + isError = true; + } else + DiagID = diag::ext_typecheck_comparison_of_pointer_integer; + + if (DiagID) { + Diag(Loc, DiagID) + << LHSType << RHSType << LHS.get()->getSourceRange() + << RHS.get()->getSourceRange(); + if (isError) + return QualType(); + } + + if (LHSType->isIntegerType()) + LHS = ImpCastExprToType(LHS.take(), RHSType, + LHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); + else + RHS = ImpCastExprToType(RHS.take(), LHSType, + RHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); + return ResultTy; + } + + // Handle block pointers. + if (!IsRelational && RHSIsNull + && LHSType->isBlockPointerType() && RHSType->isIntegerType()) { + RHS = ImpCastExprToType(RHS.take(), LHSType, CK_NullToPointer); + return ResultTy; + } + if (!IsRelational && LHSIsNull + && LHSType->isIntegerType() && RHSType->isBlockPointerType()) { + LHS = ImpCastExprToType(LHS.take(), RHSType, CK_NullToPointer); + return ResultTy; + } + + return InvalidOperands(Loc, LHS, RHS); +} + + +// Return a signed type that is of identical size and number of elements. +// For floating point vectors, return an integer type of identical size +// and number of elements. +QualType Sema::GetSignedVectorType(QualType V) { + const VectorType *VTy = V->getAs<VectorType>(); + unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); + if (TypeSize == Context.getTypeSize(Context.CharTy)) + return Context.getExtVectorType(Context.CharTy, VTy->getNumElements()); + else if (TypeSize == Context.getTypeSize(Context.ShortTy)) + return Context.getExtVectorType(Context.ShortTy, VTy->getNumElements()); + else if (TypeSize == Context.getTypeSize(Context.IntTy)) + return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); + else if (TypeSize == Context.getTypeSize(Context.LongTy)) + return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); + assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && + "Unhandled vector element size in vector compare"); + return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); +} + +/// CheckVectorCompareOperands - vector comparisons are a clang extension that +/// operates on extended vector types. Instead of producing an IntTy result, +/// like a scalar comparison, a vector comparison produces a vector of integer +/// types. +QualType Sema::CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS, + SourceLocation Loc, + bool IsRelational) { + // Check to make sure we're operating on vectors of the same type and width, + // Allowing one side to be a scalar of element type. + QualType vType = CheckVectorOperands(LHS, RHS, Loc, /*isCompAssign*/false); + if (vType.isNull()) + return vType; + + QualType LHSType = LHS.get()->getType(); + + // If AltiVec, the comparison results in a numeric type, i.e. + // bool for C++, int for C + if (vType->getAs<VectorType>()->getVectorKind() == VectorType::AltiVecVector) + return Context.getLogicalOperationType(); + + // For non-floating point types, check for self-comparisons of the form + // x == x, x != x, x < x, etc. These always evaluate to a constant, and + // often indicate logic errors in the program. + if (!LHSType->hasFloatingRepresentation()) { + if (DeclRefExpr* DRL + = dyn_cast<DeclRefExpr>(LHS.get()->IgnoreParenImpCasts())) + if (DeclRefExpr* DRR + = dyn_cast<DeclRefExpr>(RHS.get()->IgnoreParenImpCasts())) + if (DRL->getDecl() == DRR->getDecl()) + DiagRuntimeBehavior(Loc, 0, + PDiag(diag::warn_comparison_always) + << 0 // self- + << 2 // "a constant" + ); + } + + // Check for comparisons of floating point operands using != and ==. + if (!IsRelational && LHSType->hasFloatingRepresentation()) { + assert (RHS.get()->getType()->hasFloatingRepresentation()); + CheckFloatComparison(Loc, LHS.get(), RHS.get()); + } + + // Return a signed type for the vector. + return GetSignedVectorType(LHSType); +} + +QualType Sema::CheckVectorLogicalOperands(ExprResult &LHS, ExprResult &RHS, + SourceLocation Loc) { + // Ensure that either both operands are of the same vector type, or + // one operand is of a vector type and the other is of its element type. + QualType vType = CheckVectorOperands(LHS, RHS, Loc, false); + if (vType.isNull() || vType->isFloatingType()) + return InvalidOperands(Loc, LHS, RHS); + + return GetSignedVectorType(LHS.get()->getType()); +} + +inline QualType Sema::CheckBitwiseOperands( + ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) { + checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); + + if (LHS.get()->getType()->isVectorType() || + RHS.get()->getType()->isVectorType()) { + if (LHS.get()->getType()->hasIntegerRepresentation() && + RHS.get()->getType()->hasIntegerRepresentation()) + return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); + + return InvalidOperands(Loc, LHS, RHS); + } + + ExprResult LHSResult = Owned(LHS), RHSResult = Owned(RHS); + QualType compType = UsualArithmeticConversions(LHSResult, RHSResult, + IsCompAssign); + if (LHSResult.isInvalid() || RHSResult.isInvalid()) + return QualType(); + LHS = LHSResult.take(); + RHS = RHSResult.take(); + + if (LHS.get()->getType()->isIntegralOrUnscopedEnumerationType() && + RHS.get()->getType()->isIntegralOrUnscopedEnumerationType()) + return compType; + return InvalidOperands(Loc, LHS, RHS); +} + +inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] + ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, unsigned Opc) { + + // Check vector operands differently. + if (LHS.get()->getType()->isVectorType() || RHS.get()->getType()->isVectorType()) + return CheckVectorLogicalOperands(LHS, RHS, Loc); + + // Diagnose cases where the user write a logical and/or but probably meant a + // bitwise one. We do this when the LHS is a non-bool integer and the RHS + // is a constant. + if (LHS.get()->getType()->isIntegerType() && + !LHS.get()->getType()->isBooleanType() && + RHS.get()->getType()->isIntegerType() && !RHS.get()->isValueDependent() && + // Don't warn in macros or template instantiations. + !Loc.isMacroID() && ActiveTemplateInstantiations.empty()) { + // If the RHS can be constant folded, and if it constant folds to something + // that isn't 0 or 1 (which indicate a potential logical operation that + // happened to fold to true/false) then warn. + // Parens on the RHS are ignored. + llvm::APSInt Result; + if (RHS.get()->EvaluateAsInt(Result, Context)) + if ((getLangOpts().Bool && !RHS.get()->getType()->isBooleanType()) || + (Result != 0 && Result != 1)) { + Diag(Loc, diag::warn_logical_instead_of_bitwise) + << RHS.get()->getSourceRange() + << (Opc == BO_LAnd ? "&&" : "||"); + // Suggest replacing the logical operator with the bitwise version + Diag(Loc, diag::note_logical_instead_of_bitwise_change_operator) + << (Opc == BO_LAnd ? "&" : "|") + << FixItHint::CreateReplacement(SourceRange( + Loc, Lexer::getLocForEndOfToken(Loc, 0, getSourceManager(), + getLangOpts())), + Opc == BO_LAnd ? "&" : "|"); + if (Opc == BO_LAnd) + // Suggest replacing "Foo() && kNonZero" with "Foo()" + Diag(Loc, diag::note_logical_instead_of_bitwise_remove_constant) + << FixItHint::CreateRemoval( + SourceRange( + Lexer::getLocForEndOfToken(LHS.get()->getLocEnd(), + 0, getSourceManager(), + getLangOpts()), + RHS.get()->getLocEnd())); + } + } + + if (!Context.getLangOpts().CPlusPlus) { + LHS = UsualUnaryConversions(LHS.take()); + if (LHS.isInvalid()) + return QualType(); + + RHS = UsualUnaryConversions(RHS.take()); + if (RHS.isInvalid()) + return QualType(); + + if (!LHS.get()->getType()->isScalarType() || + !RHS.get()->getType()->isScalarType()) + return InvalidOperands(Loc, LHS, RHS); + + return Context.IntTy; + } + + // The following is safe because we only use this method for + // non-overloadable operands. + + // C++ [expr.log.and]p1 + // C++ [expr.log.or]p1 + // The operands are both contextually converted to type bool. + ExprResult LHSRes = PerformContextuallyConvertToBool(LHS.get()); + if (LHSRes.isInvalid()) + return InvalidOperands(Loc, LHS, RHS); + LHS = move(LHSRes); + + ExprResult RHSRes = PerformContextuallyConvertToBool(RHS.get()); + if (RHSRes.isInvalid()) + return InvalidOperands(Loc, LHS, RHS); + RHS = move(RHSRes); + + // C++ [expr.log.and]p2 + // C++ [expr.log.or]p2 + // The result is a bool. + return Context.BoolTy; +} + +/// IsReadonlyProperty - Verify that otherwise a valid l-value expression +/// is a read-only property; return true if so. A readonly property expression +/// depends on various declarations and thus must be treated specially. +/// +static bool IsReadonlyProperty(Expr *E, Sema &S) { + const ObjCPropertyRefExpr *PropExpr = dyn_cast<ObjCPropertyRefExpr>(E); + if (!PropExpr) return false; + if (PropExpr->isImplicitProperty()) return false; + + ObjCPropertyDecl *PDecl = PropExpr->getExplicitProperty(); + QualType BaseType = PropExpr->isSuperReceiver() ? + PropExpr->getSuperReceiverType() : + PropExpr->getBase()->getType(); + + if (const ObjCObjectPointerType *OPT = + BaseType->getAsObjCInterfacePointerType()) + if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) + if (S.isPropertyReadonly(PDecl, IFace)) + return true; + return false; +} + +static bool IsReadonlyMessage(Expr *E, Sema &S) { + const MemberExpr *ME = dyn_cast<MemberExpr>(E); + if (!ME) return false; + if (!isa<FieldDecl>(ME->getMemberDecl())) return false; + ObjCMessageExpr *Base = + dyn_cast<ObjCMessageExpr>(ME->getBase()->IgnoreParenImpCasts()); + if (!Base) return false; + return Base->getMethodDecl() != 0; +} + +/// Is the given expression (which must be 'const') a reference to a +/// variable which was originally non-const, but which has become +/// 'const' due to being captured within a block? +enum NonConstCaptureKind { NCCK_None, NCCK_Block, NCCK_Lambda }; +static NonConstCaptureKind isReferenceToNonConstCapture(Sema &S, Expr *E) { + assert(E->isLValue() && E->getType().isConstQualified()); + E = E->IgnoreParens(); + + // Must be a reference to a declaration from an enclosing scope. + DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E); + if (!DRE) return NCCK_None; + if (!DRE->refersToEnclosingLocal()) return NCCK_None; + + // The declaration must be a variable which is not declared 'const'. + VarDecl *var = dyn_cast<VarDecl>(DRE->getDecl()); + if (!var) return NCCK_None; + if (var->getType().isConstQualified()) return NCCK_None; + assert(var->hasLocalStorage() && "capture added 'const' to non-local?"); + + // Decide whether the first capture was for a block or a lambda. + DeclContext *DC = S.CurContext; + while (DC->getParent() != var->getDeclContext()) + DC = DC->getParent(); + return (isa<BlockDecl>(DC) ? NCCK_Block : NCCK_Lambda); +} + +/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, +/// emit an error and return true. If so, return false. +static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { + assert(!E->hasPlaceholderType(BuiltinType::PseudoObject)); + SourceLocation OrigLoc = Loc; + Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, + &Loc); + if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) + IsLV = Expr::MLV_ReadonlyProperty; + else if (IsLV == Expr::MLV_ClassTemporary && IsReadonlyMessage(E, S)) + IsLV = Expr::MLV_InvalidMessageExpression; + if (IsLV == Expr::MLV_Valid) + return false; + + unsigned Diag = 0; + bool NeedType = false; + switch (IsLV) { // C99 6.5.16p2 + case Expr::MLV_ConstQualified: + Diag = diag::err_typecheck_assign_const; + + // Use a specialized diagnostic when we're assigning to an object + // from an enclosing function or block. + if (NonConstCaptureKind NCCK = isReferenceToNonConstCapture(S, E)) { + if (NCCK == NCCK_Block) + Diag = diag::err_block_decl_ref_not_modifiable_lvalue; + else + Diag = diag::err_lambda_decl_ref_not_modifiable_lvalue; + break; + } + + // In ARC, use some specialized diagnostics for occasions where we + // infer 'const'. These are always pseudo-strong variables. + if (S.getLangOpts().ObjCAutoRefCount) { + DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts()); + if (declRef && isa<VarDecl>(declRef->getDecl())) { + VarDecl *var = cast<VarDecl>(declRef->getDecl()); + + // Use the normal diagnostic if it's pseudo-__strong but the + // user actually wrote 'const'. + if (var->isARCPseudoStrong() && + (!var->getTypeSourceInfo() || + !var->getTypeSourceInfo()->getType().isConstQualified())) { + // There are two pseudo-strong cases: + // - self + ObjCMethodDecl *method = S.getCurMethodDecl(); + if (method && var == method->getSelfDecl()) + Diag = method->isClassMethod() + ? diag::err_typecheck_arc_assign_self_class_method + : diag::err_typecheck_arc_assign_self; + + // - fast enumeration variables + else + Diag = diag::err_typecheck_arr_assign_enumeration; + + SourceRange Assign; + if (Loc != OrigLoc) + Assign = SourceRange(OrigLoc, OrigLoc); + S.Diag(Loc, Diag) << E->getSourceRange() << Assign; + // We need to preserve the AST regardless, so migration tool + // can do its job. + return false; + } + } + } + + break; + case Expr::MLV_ArrayType: + Diag = diag::err_typecheck_array_not_modifiable_lvalue; + NeedType = true; + break; + case Expr::MLV_NotObjectType: + Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; + NeedType = true; + break; + case Expr::MLV_LValueCast: + Diag = diag::err_typecheck_lvalue_casts_not_supported; + break; + case Expr::MLV_Valid: + llvm_unreachable("did not take early return for MLV_Valid"); + case Expr::MLV_InvalidExpression: + case Expr::MLV_MemberFunction: + case Expr::MLV_ClassTemporary: + Diag = diag::err_typecheck_expression_not_modifiable_lvalue; + break; + case Expr::MLV_IncompleteType: + case Expr::MLV_IncompleteVoidType: + return S.RequireCompleteType(Loc, E->getType(), + S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) + << E->getSourceRange()); + case Expr::MLV_DuplicateVectorComponents: + Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; + break; + case Expr::MLV_ReadonlyProperty: + case Expr::MLV_NoSetterProperty: + llvm_unreachable("readonly properties should be processed differently"); + case Expr::MLV_InvalidMessageExpression: + Diag = diag::error_readonly_message_assignment; + break; + case Expr::MLV_SubObjCPropertySetting: + Diag = diag::error_no_subobject_property_setting; + break; + } + + SourceRange Assign; + if (Loc != OrigLoc) + Assign = SourceRange(OrigLoc, OrigLoc); + if (NeedType) + S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; + else + S.Diag(Loc, Diag) << E->getSourceRange() << Assign; + return true; +} + + + +// C99 6.5.16.1 +QualType Sema::CheckAssignmentOperands(Expr *LHSExpr, ExprResult &RHS, + SourceLocation Loc, + QualType CompoundType) { + assert(!LHSExpr->hasPlaceholderType(BuiltinType::PseudoObject)); + + // Verify that LHS is a modifiable lvalue, and emit error if not. + if (CheckForModifiableLvalue(LHSExpr, Loc, *this)) + return QualType(); + + QualType LHSType = LHSExpr->getType(); + QualType RHSType = CompoundType.isNull() ? RHS.get()->getType() : + CompoundType; + AssignConvertType ConvTy; + if (CompoundType.isNull()) { + QualType LHSTy(LHSType); + ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS); + if (RHS.isInvalid()) + return QualType(); + // Special case of NSObject attributes on c-style pointer types. + if (ConvTy == IncompatiblePointer && + ((Context.isObjCNSObjectType(LHSType) && + RHSType->isObjCObjectPointerType()) || + (Context.isObjCNSObjectType(RHSType) && + LHSType->isObjCObjectPointerType()))) + ConvTy = Compatible; + + if (ConvTy == Compatible && + LHSType->isObjCObjectType()) + Diag(Loc, diag::err_objc_object_assignment) + << LHSType; + + // If the RHS is a unary plus or minus, check to see if they = and + are + // right next to each other. If so, the user may have typo'd "x =+ 4" + // instead of "x += 4". + Expr *RHSCheck = RHS.get(); + if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) + RHSCheck = ICE->getSubExpr(); + if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { + if ((UO->getOpcode() == UO_Plus || + UO->getOpcode() == UO_Minus) && + Loc.isFileID() && UO->getOperatorLoc().isFileID() && + // Only if the two operators are exactly adjacent. + Loc.getLocWithOffset(1) == UO->getOperatorLoc() && + // And there is a space or other character before the subexpr of the + // unary +/-. We don't want to warn on "x=-1". + Loc.getLocWithOffset(2) != UO->getSubExpr()->getLocStart() && + UO->getSubExpr()->getLocStart().isFileID()) { + Diag(Loc, diag::warn_not_compound_assign) + << (UO->getOpcode() == UO_Plus ? "+" : "-") + << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); + } + } + + if (ConvTy == Compatible) { + if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong) + checkRetainCycles(LHSExpr, RHS.get()); + else if (getLangOpts().ObjCAutoRefCount) + checkUnsafeExprAssigns(Loc, LHSExpr, RHS.get()); + } + } else { + // Compound assignment "x += y" + ConvTy = CheckAssignmentConstraints(Loc, LHSType, RHSType); + } + + if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, + RHS.get(), AA_Assigning)) + return QualType(); + + CheckForNullPointerDereference(*this, LHSExpr); + + // C99 6.5.16p3: The type of an assignment expression is the type of the + // left operand unless the left operand has qualified type, in which case + // it is the unqualified version of the type of the left operand. + // C99 6.5.16.1p2: In simple assignment, the value of the right operand + // is converted to the type of the assignment expression (above). + // C++ 5.17p1: the type of the assignment expression is that of its left + // operand. + return (getLangOpts().CPlusPlus + ? LHSType : LHSType.getUnqualifiedType()); +} + +// C99 6.5.17 +static QualType CheckCommaOperands(Sema &S, ExprResult &LHS, ExprResult &RHS, + SourceLocation Loc) { + S.DiagnoseUnusedExprResult(LHS.get()); + + LHS = S.CheckPlaceholderExpr(LHS.take()); + RHS = S.CheckPlaceholderExpr(RHS.take()); + if (LHS.isInvalid() || RHS.isInvalid()) + return QualType(); + + // C's comma performs lvalue conversion (C99 6.3.2.1) on both its + // operands, but not unary promotions. + // C++'s comma does not do any conversions at all (C++ [expr.comma]p1). + + // So we treat the LHS as a ignored value, and in C++ we allow the + // containing site to determine what should be done with the RHS. + LHS = S.IgnoredValueConversions(LHS.take()); + if (LHS.isInvalid()) + return QualType(); + + if (!S.getLangOpts().CPlusPlus) { + RHS = S.DefaultFunctionArrayLvalueConversion(RHS.take()); + if (RHS.isInvalid()) + return QualType(); + if (!RHS.get()->getType()->isVoidType()) + S.RequireCompleteType(Loc, RHS.get()->getType(), + diag::err_incomplete_type); + } + + return RHS.get()->getType(); +} + +/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine +/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. +static QualType CheckIncrementDecrementOperand(Sema &S, Expr *Op, + ExprValueKind &VK, + SourceLocation OpLoc, + bool IsInc, bool IsPrefix) { + if (Op->isTypeDependent()) + return S.Context.DependentTy; + + QualType ResType = Op->getType(); + // Atomic types can be used for increment / decrement where the non-atomic + // versions can, so ignore the _Atomic() specifier for the purpose of + // checking. + if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>()) + ResType = ResAtomicType->getValueType(); + + assert(!ResType.isNull() && "no type for increment/decrement expression"); + + if (S.getLangOpts().CPlusPlus && ResType->isBooleanType()) { + // Decrement of bool is not allowed. + if (!IsInc) { + S.Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); + return QualType(); + } + // Increment of bool sets it to true, but is deprecated. + S.Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); + } else if (ResType->isRealType()) { + // OK! + } else if (ResType->isAnyPointerType()) { + // C99 6.5.2.4p2, 6.5.6p2 + if (!checkArithmeticOpPointerOperand(S, OpLoc, Op)) + return QualType(); + + // Diagnose bad cases where we step over interface counts. + else if (!checkArithmethicPointerOnNonFragileABI(S, OpLoc, Op)) + return QualType(); + } else if (ResType->isAnyComplexType()) { + // C99 does not support ++/-- on complex types, we allow as an extension. + S.Diag(OpLoc, diag::ext_integer_increment_complex) + << ResType << Op->getSourceRange(); + } else if (ResType->isPlaceholderType()) { + ExprResult PR = S.CheckPlaceholderExpr(Op); + if (PR.isInvalid()) return QualType(); + return CheckIncrementDecrementOperand(S, PR.take(), VK, OpLoc, + IsInc, IsPrefix); + } else if (S.getLangOpts().AltiVec && ResType->isVectorType()) { + // OK! ( C/C++ Language Extensions for CBEA(Version 2.6) 10.3 ) + } else { + S.Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) + << ResType << int(IsInc) << Op->getSourceRange(); + return QualType(); + } + // At this point, we know we have a real, complex or pointer type. + // Now make sure the operand is a modifiable lvalue. + if (CheckForModifiableLvalue(Op, OpLoc, S)) + return QualType(); + // In C++, a prefix increment is the same type as the operand. Otherwise + // (in C or with postfix), the increment is the unqualified type of the + // operand. + if (IsPrefix && S.getLangOpts().CPlusPlus) { + VK = VK_LValue; + return ResType; + } else { + VK = VK_RValue; + return ResType.getUnqualifiedType(); + } +} + + +/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). +/// This routine allows us to typecheck complex/recursive expressions +/// where the declaration is needed for type checking. We only need to +/// handle cases when the expression references a function designator +/// or is an lvalue. Here are some examples: +/// - &(x) => x +/// - &*****f => f for f a function designator. +/// - &s.xx => s +/// - &s.zz[1].yy -> s, if zz is an array +/// - *(x + 1) -> x, if x is an array +/// - &"123"[2] -> 0 +/// - & __real__ x -> x +static ValueDecl *getPrimaryDecl(Expr *E) { + switch (E->getStmtClass()) { + case Stmt::DeclRefExprClass: + return cast<DeclRefExpr>(E)->getDecl(); + case Stmt::MemberExprClass: + // If this is an arrow operator, the address is an offset from + // the base's value, so the object the base refers to is + // irrelevant. + if (cast<MemberExpr>(E)->isArrow()) + return 0; + // Otherwise, the expression refers to a part of the base + return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); + case Stmt::ArraySubscriptExprClass: { + // FIXME: This code shouldn't be necessary! We should catch the implicit + // promotion of register arrays earlier. + Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); + if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { + if (ICE->getSubExpr()->getType()->isArrayType()) + return getPrimaryDecl(ICE->getSubExpr()); + } + return 0; + } + case Stmt::UnaryOperatorClass: { + UnaryOperator *UO = cast<UnaryOperator>(E); + + switch(UO->getOpcode()) { + case UO_Real: + case UO_Imag: + case UO_Extension: + return getPrimaryDecl(UO->getSubExpr()); + default: + return 0; + } + } + case Stmt::ParenExprClass: + return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); + case Stmt::ImplicitCastExprClass: + // If the result of an implicit cast is an l-value, we care about + // the sub-expression; otherwise, the result here doesn't matter. + return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); + default: + return 0; + } +} + +namespace { + enum { + AO_Bit_Field = 0, + AO_Vector_Element = 1, + AO_Property_Expansion = 2, + AO_Register_Variable = 3, + AO_No_Error = 4 + }; +} +/// \brief Diagnose invalid operand for address of operations. +/// +/// \param Type The type of operand which cannot have its address taken. +static void diagnoseAddressOfInvalidType(Sema &S, SourceLocation Loc, + Expr *E, unsigned Type) { + S.Diag(Loc, diag::err_typecheck_address_of) << Type << E->getSourceRange(); +} + +/// CheckAddressOfOperand - The operand of & must be either a function +/// designator or an lvalue designating an object. If it is an lvalue, the +/// object cannot be declared with storage class register or be a bit field. +/// Note: The usual conversions are *not* applied to the operand of the & +/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. +/// In C++, the operand might be an overloaded function name, in which case +/// we allow the '&' but retain the overloaded-function type. +static QualType CheckAddressOfOperand(Sema &S, ExprResult &OrigOp, + SourceLocation OpLoc) { + if (const BuiltinType *PTy = OrigOp.get()->getType()->getAsPlaceholderType()){ + if (PTy->getKind() == BuiltinType::Overload) { + if (!isa<OverloadExpr>(OrigOp.get()->IgnoreParens())) { + S.Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) + << OrigOp.get()->getSourceRange(); + return QualType(); + } + + return S.Context.OverloadTy; + } + + if (PTy->getKind() == BuiltinType::UnknownAny) + return S.Context.UnknownAnyTy; + + if (PTy->getKind() == BuiltinType::BoundMember) { + S.Diag(OpLoc, diag::err_invalid_form_pointer_member_function) + << OrigOp.get()->getSourceRange(); + return QualType(); + } + + OrigOp = S.CheckPlaceholderExpr(OrigOp.take()); + if (OrigOp.isInvalid()) return QualType(); + } + + if (OrigOp.get()->isTypeDependent()) + return S.Context.DependentTy; + + assert(!OrigOp.get()->getType()->isPlaceholderType()); + + // Make sure to ignore parentheses in subsequent checks + Expr *op = OrigOp.get()->IgnoreParens(); + + if (S.getLangOpts().C99) { + // Implement C99-only parts of addressof rules. + if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { + if (uOp->getOpcode() == UO_Deref) + // Per C99 6.5.3.2, the address of a deref always returns a valid result + // (assuming the deref expression is valid). + return uOp->getSubExpr()->getType(); + } + // Technically, there should be a check for array subscript + // expressions here, but the result of one is always an lvalue anyway. + } + ValueDecl *dcl = getPrimaryDecl(op); + Expr::LValueClassification lval = op->ClassifyLValue(S.Context); + unsigned AddressOfError = AO_No_Error; + + if (lval == Expr::LV_ClassTemporary) { + bool sfinae = S.isSFINAEContext(); + S.Diag(OpLoc, sfinae ? diag::err_typecheck_addrof_class_temporary + : diag::ext_typecheck_addrof_class_temporary) + << op->getType() << op->getSourceRange(); + if (sfinae) + return QualType(); + } else if (isa<ObjCSelectorExpr>(op)) { + return S.Context.getPointerType(op->getType()); + } else if (lval == Expr::LV_MemberFunction) { + // If it's an instance method, make a member pointer. + // The expression must have exactly the form &A::foo. + + // If the underlying expression isn't a decl ref, give up. + if (!isa<DeclRefExpr>(op)) { + S.Diag(OpLoc, diag::err_invalid_form_pointer_member_function) + << OrigOp.get()->getSourceRange(); + return QualType(); + } + DeclRefExpr *DRE = cast<DeclRefExpr>(op); + CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl()); + + // The id-expression was parenthesized. + if (OrigOp.get() != DRE) { + S.Diag(OpLoc, diag::err_parens_pointer_member_function) + << OrigOp.get()->getSourceRange(); + + // The method was named without a qualifier. + } else if (!DRE->getQualifier()) { + S.Diag(OpLoc, diag::err_unqualified_pointer_member_function) + << op->getSourceRange(); + } + + return S.Context.getMemberPointerType(op->getType(), + S.Context.getTypeDeclType(MD->getParent()).getTypePtr()); + } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { + // C99 6.5.3.2p1 + // The operand must be either an l-value or a function designator + if (!op->getType()->isFunctionType()) { + // Use a special diagnostic for loads from property references. + if (isa<PseudoObjectExpr>(op)) { + AddressOfError = AO_Property_Expansion; + } else { + // FIXME: emit more specific diag... + S.Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) + << op->getSourceRange(); + return QualType(); + } + } + } else if (op->getObjectKind() == OK_BitField) { // C99 6.5.3.2p1 + // The operand cannot be a bit-field + AddressOfError = AO_Bit_Field; + } else if (op->getObjectKind() == OK_VectorComponent) { + // The operand cannot be an element of a vector + AddressOfError = AO_Vector_Element; + } else if (dcl) { // C99 6.5.3.2p1 + // We have an lvalue with a decl. Make sure the decl is not declared + // with the register storage-class specifier. + if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { + // in C++ it is not error to take address of a register + // variable (c++03 7.1.1P3) + if (vd->getStorageClass() == SC_Register && + !S.getLangOpts().CPlusPlus) { + AddressOfError = AO_Register_Variable; + } + } else if (isa<FunctionTemplateDecl>(dcl)) { + return S.Context.OverloadTy; + } else if (isa<FieldDecl>(dcl) || isa<IndirectFieldDecl>(dcl)) { + // Okay: we can take the address of a field. + // Could be a pointer to member, though, if there is an explicit + // scope qualifier for the class. + if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { + DeclContext *Ctx = dcl->getDeclContext(); + if (Ctx && Ctx->isRecord()) { + if (dcl->getType()->isReferenceType()) { + S.Diag(OpLoc, + diag::err_cannot_form_pointer_to_member_of_reference_type) + << dcl->getDeclName() << dcl->getType(); + return QualType(); + } + + while (cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()) + Ctx = Ctx->getParent(); + return S.Context.getMemberPointerType(op->getType(), + S.Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); + } + } + } else if (!isa<FunctionDecl>(dcl) && !isa<NonTypeTemplateParmDecl>(dcl)) + llvm_unreachable("Unknown/unexpected decl type"); + } + + if (AddressOfError != AO_No_Error) { + diagnoseAddressOfInvalidType(S, OpLoc, op, AddressOfError); + return QualType(); + } + + if (lval == Expr::LV_IncompleteVoidType) { + // Taking the address of a void variable is technically illegal, but we + // allow it in cases which are otherwise valid. + // Example: "extern void x; void* y = &x;". + S.Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); + } + + // If the operand has type "type", the result has type "pointer to type". + if (op->getType()->isObjCObjectType()) + return S.Context.getObjCObjectPointerType(op->getType()); + return S.Context.getPointerType(op->getType()); +} + +/// CheckIndirectionOperand - Type check unary indirection (prefix '*'). +static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK, + SourceLocation OpLoc) { + if (Op->isTypeDependent()) + return S.Context.DependentTy; + + ExprResult ConvResult = S.UsualUnaryConversions(Op); + if (ConvResult.isInvalid()) + return QualType(); + Op = ConvResult.take(); + QualType OpTy = Op->getType(); + QualType Result; + + if (isa<CXXReinterpretCastExpr>(Op)) { + QualType OpOrigType = Op->IgnoreParenCasts()->getType(); + S.CheckCompatibleReinterpretCast(OpOrigType, OpTy, /*IsDereference*/true, + Op->getSourceRange()); + } + + // Note that per both C89 and C99, indirection is always legal, even if OpTy + // is an incomplete type or void. It would be possible to warn about + // dereferencing a void pointer, but it's completely well-defined, and such a + // warning is unlikely to catch any mistakes. + if (const PointerType *PT = OpTy->getAs<PointerType>()) + Result = PT->getPointeeType(); + else if (const ObjCObjectPointerType *OPT = + OpTy->getAs<ObjCObjectPointerType>()) + Result = OPT->getPointeeType(); + else { + ExprResult PR = S.CheckPlaceholderExpr(Op); + if (PR.isInvalid()) return QualType(); + if (PR.take() != Op) + return CheckIndirectionOperand(S, PR.take(), VK, OpLoc); + } + + if (Result.isNull()) { + S.Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) + << OpTy << Op->getSourceRange(); + return QualType(); + } + + // Dereferences are usually l-values... + VK = VK_LValue; + + // ...except that certain expressions are never l-values in C. + if (!S.getLangOpts().CPlusPlus && Result.isCForbiddenLValueType()) + VK = VK_RValue; + + return Result; +} + +static inline BinaryOperatorKind ConvertTokenKindToBinaryOpcode( + tok::TokenKind Kind) { + BinaryOperatorKind Opc; + switch (Kind) { + default: llvm_unreachable("Unknown binop!"); + case tok::periodstar: Opc = BO_PtrMemD; break; + case tok::arrowstar: Opc = BO_PtrMemI; break; + case tok::star: Opc = BO_Mul; break; + case tok::slash: Opc = BO_Div; break; + case tok::percent: Opc = BO_Rem; break; + case tok::plus: Opc = BO_Add; break; + case tok::minus: Opc = BO_Sub; break; + case tok::lessless: Opc = BO_Shl; break; + case tok::greatergreater: Opc = BO_Shr; break; + case tok::lessequal: Opc = BO_LE; break; + case tok::less: Opc = BO_LT; break; + case tok::greaterequal: Opc = BO_GE; break; + case tok::greater: Opc = BO_GT; break; + case tok::exclaimequal: Opc = BO_NE; break; + case tok::equalequal: Opc = BO_EQ; break; + case tok::amp: Opc = BO_And; break; + case tok::caret: Opc = BO_Xor; break; + case tok::pipe: Opc = BO_Or; break; + case tok::ampamp: Opc = BO_LAnd; break; + case tok::pipepipe: Opc = BO_LOr; break; + case tok::equal: Opc = BO_Assign; break; + case tok::starequal: Opc = BO_MulAssign; break; + case tok::slashequal: Opc = BO_DivAssign; break; + case tok::percentequal: Opc = BO_RemAssign; break; + case tok::plusequal: Opc = BO_AddAssign; break; + case tok::minusequal: Opc = BO_SubAssign; break; + case tok::lesslessequal: Opc = BO_ShlAssign; break; + case tok::greatergreaterequal: Opc = BO_ShrAssign; break; + case tok::ampequal: Opc = BO_AndAssign; break; + case tok::caretequal: Opc = BO_XorAssign; break; + case tok::pipeequal: Opc = BO_OrAssign; break; + case tok::comma: Opc = BO_Comma; break; + } + return Opc; +} + +static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode( + tok::TokenKind Kind) { + UnaryOperatorKind Opc; + switch (Kind) { + default: llvm_unreachable("Unknown unary op!"); + case tok::plusplus: Opc = UO_PreInc; break; + case tok::minusminus: Opc = UO_PreDec; break; + case tok::amp: Opc = UO_AddrOf; break; + case tok::star: Opc = UO_Deref; break; + case tok::plus: Opc = UO_Plus; break; + case tok::minus: Opc = UO_Minus; break; + case tok::tilde: Opc = UO_Not; break; + case tok::exclaim: Opc = UO_LNot; break; + case tok::kw___real: Opc = UO_Real; break; + case tok::kw___imag: Opc = UO_Imag; break; + case tok::kw___extension__: Opc = UO_Extension; break; + } + return Opc; +} + +/// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself. +/// This warning is only emitted for builtin assignment operations. It is also +/// suppressed in the event of macro expansions. +static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr, + SourceLocation OpLoc) { + if (!S.ActiveTemplateInstantiations.empty()) + return; + if (OpLoc.isInvalid() || OpLoc.isMacroID()) + return; + LHSExpr = LHSExpr->IgnoreParenImpCasts(); + RHSExpr = RHSExpr->IgnoreParenImpCasts(); + const DeclRefExpr *LHSDeclRef = dyn_cast<DeclRefExpr>(LHSExpr); + const DeclRefExpr *RHSDeclRef = dyn_cast<DeclRefExpr>(RHSExpr); + if (!LHSDeclRef || !RHSDeclRef || + LHSDeclRef->getLocation().isMacroID() || + RHSDeclRef->getLocation().isMacroID()) + return; + const ValueDecl *LHSDecl = + cast<ValueDecl>(LHSDeclRef->getDecl()->getCanonicalDecl()); + const ValueDecl *RHSDecl = + cast<ValueDecl>(RHSDeclRef->getDecl()->getCanonicalDecl()); + if (LHSDecl != RHSDecl) + return; + if (LHSDecl->getType().isVolatileQualified()) + return; + if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>()) + if (RefTy->getPointeeType().isVolatileQualified()) + return; + + S.Diag(OpLoc, diag::warn_self_assignment) + << LHSDeclRef->getType() + << LHSExpr->getSourceRange() << RHSExpr->getSourceRange(); +} + +/// CreateBuiltinBinOp - Creates a new built-in binary operation with +/// operator @p Opc at location @c TokLoc. This routine only supports +/// built-in operations; ActOnBinOp handles overloaded operators. +ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, + BinaryOperatorKind Opc, + Expr *LHSExpr, Expr *RHSExpr) { + if (getLangOpts().CPlusPlus0x && isa<InitListExpr>(RHSExpr)) { + // The syntax only allows initializer lists on the RHS of assignment, + // so we don't need to worry about accepting invalid code for + // non-assignment operators. + // C++11 5.17p9: + // The meaning of x = {v} [...] is that of x = T(v) [...]. The meaning + // of x = {} is x = T(). + InitializationKind Kind = + InitializationKind::CreateDirectList(RHSExpr->getLocStart()); + InitializedEntity Entity = + InitializedEntity::InitializeTemporary(LHSExpr->getType()); + InitializationSequence InitSeq(*this, Entity, Kind, &RHSExpr, 1); + ExprResult Init = InitSeq.Perform(*this, Entity, Kind, + MultiExprArg(&RHSExpr, 1)); + if (Init.isInvalid()) + return Init; + RHSExpr = Init.take(); + } + + ExprResult LHS = Owned(LHSExpr), RHS = Owned(RHSExpr); + QualType ResultTy; // Result type of the binary operator. + // The following two variables are used for compound assignment operators + QualType CompLHSTy; // Type of LHS after promotions for computation + QualType CompResultTy; // Type of computation result + ExprValueKind VK = VK_RValue; + ExprObjectKind OK = OK_Ordinary; + + switch (Opc) { + case BO_Assign: + ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, QualType()); + if (getLangOpts().CPlusPlus && + LHS.get()->getObjectKind() != OK_ObjCProperty) { + VK = LHS.get()->getValueKind(); + OK = LHS.get()->getObjectKind(); + } + if (!ResultTy.isNull()) + DiagnoseSelfAssignment(*this, LHS.get(), RHS.get(), OpLoc); + break; + case BO_PtrMemD: + case BO_PtrMemI: + ResultTy = CheckPointerToMemberOperands(LHS, RHS, VK, OpLoc, + Opc == BO_PtrMemI); + break; + case BO_Mul: + case BO_Div: + ResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, false, + Opc == BO_Div); + break; + case BO_Rem: + ResultTy = CheckRemainderOperands(LHS, RHS, OpLoc); + break; + case BO_Add: + ResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc); + break; + case BO_Sub: + ResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc); + break; + case BO_Shl: + case BO_Shr: + ResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc); + break; + case BO_LE: + case BO_LT: + case BO_GE: + case BO_GT: + ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc, true); + break; + case BO_EQ: + case BO_NE: + ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc, false); + break; + case BO_And: + case BO_Xor: + case BO_Or: + ResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc); + break; + case BO_LAnd: + case BO_LOr: + ResultTy = CheckLogicalOperands(LHS, RHS, OpLoc, Opc); + break; + case BO_MulAssign: + case BO_DivAssign: + CompResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, true, + Opc == BO_DivAssign); + CompLHSTy = CompResultTy; + if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) + ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); + break; + case BO_RemAssign: + CompResultTy = CheckRemainderOperands(LHS, RHS, OpLoc, true); + CompLHSTy = CompResultTy; + if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) + ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); + break; + case BO_AddAssign: + CompResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc, &CompLHSTy); + if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) + ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); + break; + case BO_SubAssign: + CompResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc, &CompLHSTy); + if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) + ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); + break; + case BO_ShlAssign: + case BO_ShrAssign: + CompResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc, true); + CompLHSTy = CompResultTy; + if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) + ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); + break; + case BO_AndAssign: + case BO_XorAssign: + case BO_OrAssign: + CompResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc, true); + CompLHSTy = CompResultTy; + if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) + ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); + break; + case BO_Comma: + ResultTy = CheckCommaOperands(*this, LHS, RHS, OpLoc); + if (getLangOpts().CPlusPlus && !RHS.isInvalid()) { + VK = RHS.get()->getValueKind(); + OK = RHS.get()->getObjectKind(); + } + break; + } + if (ResultTy.isNull() || LHS.isInvalid() || RHS.isInvalid()) + return ExprError(); + + // Check for array bounds violations for both sides of the BinaryOperator + CheckArrayAccess(LHS.get()); + CheckArrayAccess(RHS.get()); + + if (CompResultTy.isNull()) + return Owned(new (Context) BinaryOperator(LHS.take(), RHS.take(), Opc, + ResultTy, VK, OK, OpLoc)); + if (getLangOpts().CPlusPlus && LHS.get()->getObjectKind() != + OK_ObjCProperty) { + VK = VK_LValue; + OK = LHS.get()->getObjectKind(); + } + return Owned(new (Context) CompoundAssignOperator(LHS.take(), RHS.take(), Opc, + ResultTy, VK, OK, CompLHSTy, + CompResultTy, OpLoc)); +} + +/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison +/// operators are mixed in a way that suggests that the programmer forgot that +/// comparison operators have higher precedence. The most typical example of +/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". +static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc, + SourceLocation OpLoc, Expr *LHSExpr, + Expr *RHSExpr) { + typedef BinaryOperator BinOp; + BinOp::Opcode LHSopc = static_cast<BinOp::Opcode>(-1), + RHSopc = static_cast<BinOp::Opcode>(-1); + if (BinOp *BO = dyn_cast<BinOp>(LHSExpr)) + LHSopc = BO->getOpcode(); + if (BinOp *BO = dyn_cast<BinOp>(RHSExpr)) + RHSopc = BO->getOpcode(); + + // Subs are not binary operators. + if (LHSopc == -1 && RHSopc == -1) + return; + + // Bitwise operations are sometimes used as eager logical ops. + // Don't diagnose this. + if ((BinOp::isComparisonOp(LHSopc) || BinOp::isBitwiseOp(LHSopc)) && + (BinOp::isComparisonOp(RHSopc) || BinOp::isBitwiseOp(RHSopc))) + return; + + bool isLeftComp = BinOp::isComparisonOp(LHSopc); + bool isRightComp = BinOp::isComparisonOp(RHSopc); + if (!isLeftComp && !isRightComp) return; + + SourceRange DiagRange = isLeftComp ? SourceRange(LHSExpr->getLocStart(), + OpLoc) + : SourceRange(OpLoc, RHSExpr->getLocEnd()); + std::string OpStr = isLeftComp ? BinOp::getOpcodeStr(LHSopc) + : BinOp::getOpcodeStr(RHSopc); + SourceRange ParensRange = isLeftComp ? + SourceRange(cast<BinOp>(LHSExpr)->getRHS()->getLocStart(), + RHSExpr->getLocEnd()) + : SourceRange(LHSExpr->getLocStart(), + cast<BinOp>(RHSExpr)->getLHS()->getLocStart()); + + Self.Diag(OpLoc, diag::warn_precedence_bitwise_rel) + << DiagRange << BinOp::getOpcodeStr(Opc) << OpStr; + SuggestParentheses(Self, OpLoc, + Self.PDiag(diag::note_precedence_bitwise_silence) << OpStr, + RHSExpr->getSourceRange()); + SuggestParentheses(Self, OpLoc, + Self.PDiag(diag::note_precedence_bitwise_first) << BinOp::getOpcodeStr(Opc), + ParensRange); +} + +/// \brief It accepts a '&' expr that is inside a '|' one. +/// Emit a diagnostic together with a fixit hint that wraps the '&' expression +/// in parentheses. +static void +EmitDiagnosticForBitwiseAndInBitwiseOr(Sema &Self, SourceLocation OpLoc, + BinaryOperator *Bop) { + assert(Bop->getOpcode() == BO_And); + Self.Diag(Bop->getOperatorLoc(), diag::warn_bitwise_and_in_bitwise_or) + << Bop->getSourceRange() << OpLoc; + SuggestParentheses(Self, Bop->getOperatorLoc(), + Self.PDiag(diag::note_bitwise_and_in_bitwise_or_silence), + Bop->getSourceRange()); +} + +/// \brief It accepts a '&&' expr that is inside a '||' one. +/// Emit a diagnostic together with a fixit hint that wraps the '&&' expression +/// in parentheses. +static void +EmitDiagnosticForLogicalAndInLogicalOr(Sema &Self, SourceLocation OpLoc, + BinaryOperator *Bop) { + assert(Bop->getOpcode() == BO_LAnd); + Self.Diag(Bop->getOperatorLoc(), diag::warn_logical_and_in_logical_or) + << Bop->getSourceRange() << OpLoc; + SuggestParentheses(Self, Bop->getOperatorLoc(), + Self.PDiag(diag::note_logical_and_in_logical_or_silence), + Bop->getSourceRange()); +} + +/// \brief Returns true if the given expression can be evaluated as a constant +/// 'true'. +static bool EvaluatesAsTrue(Sema &S, Expr *E) { + bool Res; + return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && Res; +} + +/// \brief Returns true if the given expression can be evaluated as a constant +/// 'false'. +static bool EvaluatesAsFalse(Sema &S, Expr *E) { + bool Res; + return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && !Res; +} + +/// \brief Look for '&&' in the left hand of a '||' expr. +static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc, + Expr *LHSExpr, Expr *RHSExpr) { + if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(LHSExpr)) { + if (Bop->getOpcode() == BO_LAnd) { + // If it's "a && b || 0" don't warn since the precedence doesn't matter. + if (EvaluatesAsFalse(S, RHSExpr)) + return; + // If it's "1 && a || b" don't warn since the precedence doesn't matter. + if (!EvaluatesAsTrue(S, Bop->getLHS())) + return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); + } else if (Bop->getOpcode() == BO_LOr) { + if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Bop->getRHS())) { + // If it's "a || b && 1 || c" we didn't warn earlier for + // "a || b && 1", but warn now. + if (RBop->getOpcode() == BO_LAnd && EvaluatesAsTrue(S, RBop->getRHS())) + return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, RBop); + } + } + } +} + +/// \brief Look for '&&' in the right hand of a '||' expr. +static void DiagnoseLogicalAndInLogicalOrRHS(Sema &S, SourceLocation OpLoc, + Expr *LHSExpr, Expr *RHSExpr) { + if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(RHSExpr)) { + if (Bop->getOpcode() == BO_LAnd) { + // If it's "0 || a && b" don't warn since the precedence doesn't matter. + if (EvaluatesAsFalse(S, LHSExpr)) + return; + // If it's "a || b && 1" don't warn since the precedence doesn't matter. + if (!EvaluatesAsTrue(S, Bop->getRHS())) + return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); + } + } +} + +/// \brief Look for '&' in the left or right hand of a '|' expr. +static void DiagnoseBitwiseAndInBitwiseOr(Sema &S, SourceLocation OpLoc, + Expr *OrArg) { + if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(OrArg)) { + if (Bop->getOpcode() == BO_And) + return EmitDiagnosticForBitwiseAndInBitwiseOr(S, OpLoc, Bop); + } +} + +/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky +/// precedence. +static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc, + SourceLocation OpLoc, Expr *LHSExpr, + Expr *RHSExpr){ + // Diagnose "arg1 'bitwise' arg2 'eq' arg3". + if (BinaryOperator::isBitwiseOp(Opc)) + DiagnoseBitwisePrecedence(Self, Opc, OpLoc, LHSExpr, RHSExpr); + + // Diagnose "arg1 & arg2 | arg3" + if (Opc == BO_Or && !OpLoc.isMacroID()/* Don't warn in macros. */) { + DiagnoseBitwiseAndInBitwiseOr(Self, OpLoc, LHSExpr); + DiagnoseBitwiseAndInBitwiseOr(Self, OpLoc, RHSExpr); + } + + // Warn about arg1 || arg2 && arg3, as GCC 4.3+ does. + // We don't warn for 'assert(a || b && "bad")' since this is safe. + if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) { + DiagnoseLogicalAndInLogicalOrLHS(Self, OpLoc, LHSExpr, RHSExpr); + DiagnoseLogicalAndInLogicalOrRHS(Self, OpLoc, LHSExpr, RHSExpr); + } +} + +// Binary Operators. 'Tok' is the token for the operator. +ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, + tok::TokenKind Kind, + Expr *LHSExpr, Expr *RHSExpr) { + BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind); + assert((LHSExpr != 0) && "ActOnBinOp(): missing left expression"); + assert((RHSExpr != 0) && "ActOnBinOp(): missing right expression"); + + // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" + DiagnoseBinOpPrecedence(*this, Opc, TokLoc, LHSExpr, RHSExpr); + + return BuildBinOp(S, TokLoc, Opc, LHSExpr, RHSExpr); +} + +/// Build an overloaded binary operator expression in the given scope. +static ExprResult BuildOverloadedBinOp(Sema &S, Scope *Sc, SourceLocation OpLoc, + BinaryOperatorKind Opc, + Expr *LHS, Expr *RHS) { + // Find all of the overloaded operators visible from this + // point. We perform both an operator-name lookup from the local + // scope and an argument-dependent lookup based on the types of + // the arguments. + UnresolvedSet<16> Functions; + OverloadedOperatorKind OverOp + = BinaryOperator::getOverloadedOperator(Opc); + if (Sc && OverOp != OO_None) + S.LookupOverloadedOperatorName(OverOp, Sc, LHS->getType(), + RHS->getType(), Functions); + + // Build the (potentially-overloaded, potentially-dependent) + // binary operation. + return S.CreateOverloadedBinOp(OpLoc, Opc, Functions, LHS, RHS); +} + +ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, + BinaryOperatorKind Opc, + Expr *LHSExpr, Expr *RHSExpr) { + // We want to end up calling one of checkPseudoObjectAssignment + // (if the LHS is a pseudo-object), BuildOverloadedBinOp (if + // both expressions are overloadable or either is type-dependent), + // or CreateBuiltinBinOp (in any other case). We also want to get + // any placeholder types out of the way. + + // Handle pseudo-objects in the LHS. + if (const BuiltinType *pty = LHSExpr->getType()->getAsPlaceholderType()) { + // Assignments with a pseudo-object l-value need special analysis. + if (pty->getKind() == BuiltinType::PseudoObject && + BinaryOperator::isAssignmentOp(Opc)) + return checkPseudoObjectAssignment(S, OpLoc, Opc, LHSExpr, RHSExpr); + + // Don't resolve overloads if the other type is overloadable. + if (pty->getKind() == BuiltinType::Overload) { + // We can't actually test that if we still have a placeholder, + // though. Fortunately, none of the exceptions we see in that + // code below are valid when the LHS is an overload set. Note + // that an overload set can be dependently-typed, but it never + // instantiates to having an overloadable type. + ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr); + if (resolvedRHS.isInvalid()) return ExprError(); + RHSExpr = resolvedRHS.take(); + + if (RHSExpr->isTypeDependent() || + RHSExpr->getType()->isOverloadableType()) + return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); + } + + ExprResult LHS = CheckPlaceholderExpr(LHSExpr); + if (LHS.isInvalid()) return ExprError(); + LHSExpr = LHS.take(); + } + + // Handle pseudo-objects in the RHS. + if (const BuiltinType *pty = RHSExpr->getType()->getAsPlaceholderType()) { + // An overload in the RHS can potentially be resolved by the type + // being assigned to. + if (Opc == BO_Assign && pty->getKind() == BuiltinType::Overload) { + if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent()) + return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); + + if (LHSExpr->getType()->isOverloadableType()) + return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); + + return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr); + } + + // Don't resolve overloads if the other type is overloadable. + if (pty->getKind() == BuiltinType::Overload && + LHSExpr->getType()->isOverloadableType()) + return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); + + ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr); + if (!resolvedRHS.isUsable()) return ExprError(); + RHSExpr = resolvedRHS.take(); + } + + if (getLangOpts().CPlusPlus) { + // If either expression is type-dependent, always build an + // overloaded op. + if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent()) + return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); + + // Otherwise, build an overloaded op if either expression has an + // overloadable type. + if (LHSExpr->getType()->isOverloadableType() || + RHSExpr->getType()->isOverloadableType()) + return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); + } + + // Build a built-in binary operation. + return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr); +} + +ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, + UnaryOperatorKind Opc, + Expr *InputExpr) { + ExprResult Input = Owned(InputExpr); + ExprValueKind VK = VK_RValue; + ExprObjectKind OK = OK_Ordinary; + QualType resultType; + switch (Opc) { + case UO_PreInc: + case UO_PreDec: + case UO_PostInc: + case UO_PostDec: + resultType = CheckIncrementDecrementOperand(*this, Input.get(), VK, OpLoc, + Opc == UO_PreInc || + Opc == UO_PostInc, + Opc == UO_PreInc || + Opc == UO_PreDec); + break; + case UO_AddrOf: + resultType = CheckAddressOfOperand(*this, Input, OpLoc); + break; + case UO_Deref: { + Input = DefaultFunctionArrayLvalueConversion(Input.take()); + resultType = CheckIndirectionOperand(*this, Input.get(), VK, OpLoc); + break; + } + case UO_Plus: + case UO_Minus: + Input = UsualUnaryConversions(Input.take()); + if (Input.isInvalid()) return ExprError(); + resultType = Input.get()->getType(); + if (resultType->isDependentType()) + break; + if (resultType->isArithmeticType() || // C99 6.5.3.3p1 + resultType->isVectorType()) + break; + else if (getLangOpts().CPlusPlus && // C++ [expr.unary.op]p6-7 + resultType->isEnumeralType()) + break; + else if (getLangOpts().CPlusPlus && // C++ [expr.unary.op]p6 + Opc == UO_Plus && + resultType->isPointerType()) + break; + + return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) + << resultType << Input.get()->getSourceRange()); + + case UO_Not: // bitwise complement + Input = UsualUnaryConversions(Input.take()); + if (Input.isInvalid()) return ExprError(); + resultType = Input.get()->getType(); + if (resultType->isDependentType()) + break; + // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. + if (resultType->isComplexType() || resultType->isComplexIntegerType()) + // C99 does not support '~' for complex conjugation. + Diag(OpLoc, diag::ext_integer_complement_complex) + << resultType << Input.get()->getSourceRange(); + else if (resultType->hasIntegerRepresentation()) + break; + else { + return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) + << resultType << Input.get()->getSourceRange()); + } + break; + + case UO_LNot: // logical negation + // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). + Input = DefaultFunctionArrayLvalueConversion(Input.take()); + if (Input.isInvalid()) return ExprError(); + resultType = Input.get()->getType(); + + // Though we still have to promote half FP to float... + if (resultType->isHalfType()) { + Input = ImpCastExprToType(Input.take(), Context.FloatTy, CK_FloatingCast).take(); + resultType = Context.FloatTy; + } + + if (resultType->isDependentType()) + break; + if (resultType->isScalarType()) { + // C99 6.5.3.3p1: ok, fallthrough; + if (Context.getLangOpts().CPlusPlus) { + // C++03 [expr.unary.op]p8, C++0x [expr.unary.op]p9: + // operand contextually converted to bool. + Input = ImpCastExprToType(Input.take(), Context.BoolTy, + ScalarTypeToBooleanCastKind(resultType)); + } + } else if (resultType->isExtVectorType()) { + // Vector logical not returns the signed variant of the operand type. + resultType = GetSignedVectorType(resultType); + break; + } else { + return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) + << resultType << Input.get()->getSourceRange()); + } + + // LNot always has type int. C99 6.5.3.3p5. + // In C++, it's bool. C++ 5.3.1p8 + resultType = Context.getLogicalOperationType(); + break; + case UO_Real: + case UO_Imag: + resultType = CheckRealImagOperand(*this, Input, OpLoc, Opc == UO_Real); + // _Real maps ordinary l-values into ordinary l-values. _Imag maps ordinary + // complex l-values to ordinary l-values and all other values to r-values. + if (Input.isInvalid()) return ExprError(); + if (Opc == UO_Real || Input.get()->getType()->isAnyComplexType()) { + if (Input.get()->getValueKind() != VK_RValue && + Input.get()->getObjectKind() == OK_Ordinary) + VK = Input.get()->getValueKind(); + } else if (!getLangOpts().CPlusPlus) { + // In C, a volatile scalar is read by __imag. In C++, it is not. + Input = DefaultLvalueConversion(Input.take()); + } + break; + case UO_Extension: + resultType = Input.get()->getType(); + VK = Input.get()->getValueKind(); + OK = Input.get()->getObjectKind(); + break; + } + if (resultType.isNull() || Input.isInvalid()) + return ExprError(); + + // Check for array bounds violations in the operand of the UnaryOperator, + // except for the '*' and '&' operators that have to be handled specially + // by CheckArrayAccess (as there are special cases like &array[arraysize] + // that are explicitly defined as valid by the standard). + if (Opc != UO_AddrOf && Opc != UO_Deref) + CheckArrayAccess(Input.get()); + + return Owned(new (Context) UnaryOperator(Input.take(), Opc, resultType, + VK, OK, OpLoc)); +} + +/// \brief Determine whether the given expression is a qualified member +/// access expression, of a form that could be turned into a pointer to member +/// with the address-of operator. +static bool isQualifiedMemberAccess(Expr *E) { + if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) { + if (!DRE->getQualifier()) + return false; + + ValueDecl *VD = DRE->getDecl(); + if (!VD->isCXXClassMember()) + return false; + + if (isa<FieldDecl>(VD) || isa<IndirectFieldDecl>(VD)) + return true; + if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(VD)) + return Method->isInstance(); + + return false; + } + + if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) { + if (!ULE->getQualifier()) + return false; + + for (UnresolvedLookupExpr::decls_iterator D = ULE->decls_begin(), + DEnd = ULE->decls_end(); + D != DEnd; ++D) { + if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(*D)) { + if (Method->isInstance()) + return true; + } else { + // Overload set does not contain methods. + break; + } + } + + return false; + } + + return false; +} + +ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, + UnaryOperatorKind Opc, Expr *Input) { + // First things first: handle placeholders so that the + // overloaded-operator check considers the right type. + if (const BuiltinType *pty = Input->getType()->getAsPlaceholderType()) { + // Increment and decrement of pseudo-object references. + if (pty->getKind() == BuiltinType::PseudoObject && + UnaryOperator::isIncrementDecrementOp(Opc)) + return checkPseudoObjectIncDec(S, OpLoc, Opc, Input); + + // extension is always a builtin operator. + if (Opc == UO_Extension) + return CreateBuiltinUnaryOp(OpLoc, Opc, Input); + + // & gets special logic for several kinds of placeholder. + // The builtin code knows what to do. + if (Opc == UO_AddrOf && + (pty->getKind() == BuiltinType::Overload || + pty->getKind() == BuiltinType::UnknownAny || + pty->getKind() == BuiltinType::BoundMember)) + return CreateBuiltinUnaryOp(OpLoc, Opc, Input); + + // Anything else needs to be handled now. + ExprResult Result = CheckPlaceholderExpr(Input); + if (Result.isInvalid()) return ExprError(); + Input = Result.take(); + } + + if (getLangOpts().CPlusPlus && Input->getType()->isOverloadableType() && + UnaryOperator::getOverloadedOperator(Opc) != OO_None && + !(Opc == UO_AddrOf && isQualifiedMemberAccess(Input))) { + // Find all of the overloaded operators visible from this + // point. We perform both an operator-name lookup from the local + // scope and an argument-dependent lookup based on the types of + // the arguments. + UnresolvedSet<16> Functions; + OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); + if (S && OverOp != OO_None) + LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), + Functions); + + return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, Input); + } + + return CreateBuiltinUnaryOp(OpLoc, Opc, Input); +} + +// Unary Operators. 'Tok' is the token for the operator. +ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, + tok::TokenKind Op, Expr *Input) { + return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), Input); +} + +/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". +ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc, + LabelDecl *TheDecl) { + TheDecl->setUsed(); + // Create the AST node. The address of a label always has type 'void*'. + return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, TheDecl, + Context.getPointerType(Context.VoidTy))); +} + +/// Given the last statement in a statement-expression, check whether +/// the result is a producing expression (like a call to an +/// ns_returns_retained function) and, if so, rebuild it to hoist the +/// release out of the full-expression. Otherwise, return null. +/// Cannot fail. +static Expr *maybeRebuildARCConsumingStmt(Stmt *Statement) { + // Should always be wrapped with one of these. + ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(Statement); + if (!cleanups) return 0; + + ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(cleanups->getSubExpr()); + if (!cast || cast->getCastKind() != CK_ARCConsumeObject) + return 0; + + // Splice out the cast. This shouldn't modify any interesting + // features of the statement. + Expr *producer = cast->getSubExpr(); + assert(producer->getType() == cast->getType()); + assert(producer->getValueKind() == cast->getValueKind()); + cleanups->setSubExpr(producer); + return cleanups; +} + +void Sema::ActOnStartStmtExpr() { + PushExpressionEvaluationContext(ExprEvalContexts.back().Context); +} + +void Sema::ActOnStmtExprError() { + // Note that function is also called by TreeTransform when leaving a + // StmtExpr scope without rebuilding anything. + + DiscardCleanupsInEvaluationContext(); + PopExpressionEvaluationContext(); +} + +ExprResult +Sema::ActOnStmtExpr(SourceLocation LPLoc, Stmt *SubStmt, + SourceLocation RPLoc) { // "({..})" + assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); + CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); + + if (hasAnyUnrecoverableErrorsInThisFunction()) + DiscardCleanupsInEvaluationContext(); + assert(!ExprNeedsCleanups && "cleanups within StmtExpr not correctly bound!"); + PopExpressionEvaluationContext(); + + bool isFileScope + = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); + if (isFileScope) + return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); + + // FIXME: there are a variety of strange constraints to enforce here, for + // example, it is not possible to goto into a stmt expression apparently. + // More semantic analysis is needed. + + // If there are sub stmts in the compound stmt, take the type of the last one + // as the type of the stmtexpr. + QualType Ty = Context.VoidTy; + bool StmtExprMayBindToTemp = false; + if (!Compound->body_empty()) { + Stmt *LastStmt = Compound->body_back(); + LabelStmt *LastLabelStmt = 0; + // If LastStmt is a label, skip down through into the body. + while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) { + LastLabelStmt = Label; + LastStmt = Label->getSubStmt(); + } + + if (Expr *LastE = dyn_cast<Expr>(LastStmt)) { + // Do function/array conversion on the last expression, but not + // lvalue-to-rvalue. However, initialize an unqualified type. + ExprResult LastExpr = DefaultFunctionArrayConversion(LastE); + if (LastExpr.isInvalid()) + return ExprError(); + Ty = LastExpr.get()->getType().getUnqualifiedType(); + + if (!Ty->isDependentType() && !LastExpr.get()->isTypeDependent()) { + // In ARC, if the final expression ends in a consume, splice + // the consume out and bind it later. In the alternate case + // (when dealing with a retainable type), the result + // initialization will create a produce. In both cases the + // result will be +1, and we'll need to balance that out with + // a bind. + if (Expr *rebuiltLastStmt + = maybeRebuildARCConsumingStmt(LastExpr.get())) { + LastExpr = rebuiltLastStmt; + } else { + LastExpr = PerformCopyInitialization( + InitializedEntity::InitializeResult(LPLoc, + Ty, + false), + SourceLocation(), + LastExpr); + } + + if (LastExpr.isInvalid()) + return ExprError(); + if (LastExpr.get() != 0) { + if (!LastLabelStmt) + Compound->setLastStmt(LastExpr.take()); + else + LastLabelStmt->setSubStmt(LastExpr.take()); + StmtExprMayBindToTemp = true; + } + } + } + } + + // FIXME: Check that expression type is complete/non-abstract; statement + // expressions are not lvalues. + Expr *ResStmtExpr = new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc); + if (StmtExprMayBindToTemp) + return MaybeBindToTemporary(ResStmtExpr); + return Owned(ResStmtExpr); +} + +ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, + TypeSourceInfo *TInfo, + OffsetOfComponent *CompPtr, + unsigned NumComponents, + SourceLocation RParenLoc) { + QualType ArgTy = TInfo->getType(); + bool Dependent = ArgTy->isDependentType(); + SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange(); + + // We must have at least one component that refers to the type, and the first + // one is known to be a field designator. Verify that the ArgTy represents + // a struct/union/class. + if (!Dependent && !ArgTy->isRecordType()) + return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) + << ArgTy << TypeRange); + + // Type must be complete per C99 7.17p3 because a declaring a variable + // with an incomplete type would be ill-formed. + if (!Dependent + && RequireCompleteType(BuiltinLoc, ArgTy, + PDiag(diag::err_offsetof_incomplete_type) + << TypeRange)) + return ExprError(); + + // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a + // GCC extension, diagnose them. + // FIXME: This diagnostic isn't actually visible because the location is in + // a system header! + if (NumComponents != 1) + Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) + << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); + + bool DidWarnAboutNonPOD = false; + QualType CurrentType = ArgTy; + typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; + SmallVector<OffsetOfNode, 4> Comps; + SmallVector<Expr*, 4> Exprs; + for (unsigned i = 0; i != NumComponents; ++i) { + const OffsetOfComponent &OC = CompPtr[i]; + if (OC.isBrackets) { + // Offset of an array sub-field. TODO: Should we allow vector elements? + if (!CurrentType->isDependentType()) { + const ArrayType *AT = Context.getAsArrayType(CurrentType); + if(!AT) + return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) + << CurrentType); + CurrentType = AT->getElementType(); + } else + CurrentType = Context.DependentTy; + + ExprResult IdxRval = DefaultLvalueConversion(static_cast<Expr*>(OC.U.E)); + if (IdxRval.isInvalid()) + return ExprError(); + Expr *Idx = IdxRval.take(); + + // The expression must be an integral expression. + // FIXME: An integral constant expression? + if (!Idx->isTypeDependent() && !Idx->isValueDependent() && + !Idx->getType()->isIntegerType()) + return ExprError(Diag(Idx->getLocStart(), + diag::err_typecheck_subscript_not_integer) + << Idx->getSourceRange()); + + // Record this array index. + Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); + Exprs.push_back(Idx); + continue; + } + + // Offset of a field. + if (CurrentType->isDependentType()) { + // We have the offset of a field, but we can't look into the dependent + // type. Just record the identifier of the field. + Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); + CurrentType = Context.DependentTy; + continue; + } + + // We need to have a complete type to look into. + if (RequireCompleteType(OC.LocStart, CurrentType, + diag::err_offsetof_incomplete_type)) + return ExprError(); + + // Look for the designated field. + const RecordType *RC = CurrentType->getAs<RecordType>(); + if (!RC) + return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) + << CurrentType); + RecordDecl *RD = RC->getDecl(); + + // C++ [lib.support.types]p5: + // The macro offsetof accepts a restricted set of type arguments in this + // International Standard. type shall be a POD structure or a POD union + // (clause 9). + if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { + if (!CRD->isPOD() && !DidWarnAboutNonPOD && + DiagRuntimeBehavior(BuiltinLoc, 0, + PDiag(diag::warn_offsetof_non_pod_type) + << SourceRange(CompPtr[0].LocStart, OC.LocEnd) + << CurrentType)) + DidWarnAboutNonPOD = true; + } + + // Look for the field. + LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); + LookupQualifiedName(R, RD); + FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); + IndirectFieldDecl *IndirectMemberDecl = 0; + if (!MemberDecl) { + if ((IndirectMemberDecl = R.getAsSingle<IndirectFieldDecl>())) + MemberDecl = IndirectMemberDecl->getAnonField(); + } + + if (!MemberDecl) + return ExprError(Diag(BuiltinLoc, diag::err_no_member) + << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, + OC.LocEnd)); + + // C99 7.17p3: + // (If the specified member is a bit-field, the behavior is undefined.) + // + // We diagnose this as an error. + if (MemberDecl->isBitField()) { + Diag(OC.LocEnd, diag::err_offsetof_bitfield) + << MemberDecl->getDeclName() + << SourceRange(BuiltinLoc, RParenLoc); + Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); + return ExprError(); + } + + RecordDecl *Parent = MemberDecl->getParent(); + if (IndirectMemberDecl) + Parent = cast<RecordDecl>(IndirectMemberDecl->getDeclContext()); + + // If the member was found in a base class, introduce OffsetOfNodes for + // the base class indirections. + CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, + /*DetectVirtual=*/false); + if (IsDerivedFrom(CurrentType, Context.getTypeDeclType(Parent), Paths)) { + CXXBasePath &Path = Paths.front(); + for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); + B != BEnd; ++B) + Comps.push_back(OffsetOfNode(B->Base)); + } + + if (IndirectMemberDecl) { + for (IndirectFieldDecl::chain_iterator FI = + IndirectMemberDecl->chain_begin(), + FEnd = IndirectMemberDecl->chain_end(); FI != FEnd; FI++) { + assert(isa<FieldDecl>(*FI)); + Comps.push_back(OffsetOfNode(OC.LocStart, + cast<FieldDecl>(*FI), OC.LocEnd)); + } + } else + Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); + + CurrentType = MemberDecl->getType().getNonReferenceType(); + } + + return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, + TInfo, Comps.data(), Comps.size(), + Exprs.data(), Exprs.size(), RParenLoc)); +} + +ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, + SourceLocation BuiltinLoc, + SourceLocation TypeLoc, + ParsedType ParsedArgTy, + OffsetOfComponent *CompPtr, + unsigned NumComponents, + SourceLocation RParenLoc) { + + TypeSourceInfo *ArgTInfo; + QualType ArgTy = GetTypeFromParser(ParsedArgTy, &ArgTInfo); + if (ArgTy.isNull()) + return ExprError(); + + if (!ArgTInfo) + ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); + + return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, + RParenLoc); +} + + +ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, + Expr *CondExpr, + Expr *LHSExpr, Expr *RHSExpr, + SourceLocation RPLoc) { + assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); + + ExprValueKind VK = VK_RValue; + ExprObjectKind OK = OK_Ordinary; + QualType resType; + bool ValueDependent = false; + if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { + resType = Context.DependentTy; + ValueDependent = true; + } else { + // The conditional expression is required to be a constant expression. + llvm::APSInt condEval(32); + ExprResult CondICE = VerifyIntegerConstantExpression(CondExpr, &condEval, + PDiag(diag::err_typecheck_choose_expr_requires_constant), false); + if (CondICE.isInvalid()) + return ExprError(); + CondExpr = CondICE.take(); + + // If the condition is > zero, then the AST type is the same as the LSHExpr. + Expr *ActiveExpr = condEval.getZExtValue() ? LHSExpr : RHSExpr; + + resType = ActiveExpr->getType(); + ValueDependent = ActiveExpr->isValueDependent(); + VK = ActiveExpr->getValueKind(); + OK = ActiveExpr->getObjectKind(); + } + + return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, + resType, VK, OK, RPLoc, + resType->isDependentType(), + ValueDependent)); +} + +//===----------------------------------------------------------------------===// +// Clang Extensions. +//===----------------------------------------------------------------------===// + +/// ActOnBlockStart - This callback is invoked when a block literal is started. +void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope) { + BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); + PushBlockScope(CurScope, Block); + CurContext->addDecl(Block); + if (CurScope) + PushDeclContext(CurScope, Block); + else + CurContext = Block; + + getCurBlock()->HasImplicitReturnType = true; + + // Enter a new evaluation context to insulate the block from any + // cleanups from the enclosing full-expression. + PushExpressionEvaluationContext(PotentiallyEvaluated); +} + +void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { + assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); + assert(ParamInfo.getContext() == Declarator::BlockLiteralContext); + BlockScopeInfo *CurBlock = getCurBlock(); + + TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope); + QualType T = Sig->getType(); + + // GetTypeForDeclarator always produces a function type for a block + // literal signature. Furthermore, it is always a FunctionProtoType + // unless the function was written with a typedef. + assert(T->isFunctionType() && + "GetTypeForDeclarator made a non-function block signature"); + + // Look for an explicit signature in that function type. + FunctionProtoTypeLoc ExplicitSignature; + + TypeLoc tmp = Sig->getTypeLoc().IgnoreParens(); + if (isa<FunctionProtoTypeLoc>(tmp)) { + ExplicitSignature = cast<FunctionProtoTypeLoc>(tmp); + + // Check whether that explicit signature was synthesized by + // GetTypeForDeclarator. If so, don't save that as part of the + // written signature. + if (ExplicitSignature.getLocalRangeBegin() == + ExplicitSignature.getLocalRangeEnd()) { + // This would be much cheaper if we stored TypeLocs instead of + // TypeSourceInfos. + TypeLoc Result = ExplicitSignature.getResultLoc(); + unsigned Size = Result.getFullDataSize(); + Sig = Context.CreateTypeSourceInfo(Result.getType(), Size); + Sig->getTypeLoc().initializeFullCopy(Result, Size); + + ExplicitSignature = FunctionProtoTypeLoc(); + } + } + + CurBlock->TheDecl->setSignatureAsWritten(Sig); + CurBlock->FunctionType = T; + + const FunctionType *Fn = T->getAs<FunctionType>(); + QualType RetTy = Fn->getResultType(); + bool isVariadic = + (isa<FunctionProtoType>(Fn) && cast<FunctionProtoType>(Fn)->isVariadic()); + + CurBlock->TheDecl->setIsVariadic(isVariadic); + + // Don't allow returning a objc interface by value. + if (RetTy->isObjCObjectType()) { + Diag(ParamInfo.getLocStart(), + diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; + return; + } + + // Context.DependentTy is used as a placeholder for a missing block + // return type. TODO: what should we do with declarators like: + // ^ * { ... } + // If the answer is "apply template argument deduction".... + if (RetTy != Context.DependentTy) { + CurBlock->ReturnType = RetTy; + CurBlock->TheDecl->setBlockMissingReturnType(false); + CurBlock->HasImplicitReturnType = false; + } + + // Push block parameters from the declarator if we had them. + SmallVector<ParmVarDecl*, 8> Params; + if (ExplicitSignature) { + for (unsigned I = 0, E = ExplicitSignature.getNumArgs(); I != E; ++I) { + ParmVarDecl *Param = ExplicitSignature.getArg(I); + if (Param->getIdentifier() == 0 && + !Param->isImplicit() && + !Param->isInvalidDecl() && + !getLangOpts().CPlusPlus) + Diag(Param->getLocation(), diag::err_parameter_name_omitted); + Params.push_back(Param); + } + + // Fake up parameter variables if we have a typedef, like + // ^ fntype { ... } + } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) { + for (FunctionProtoType::arg_type_iterator + I = Fn->arg_type_begin(), E = Fn->arg_type_end(); I != E; ++I) { + ParmVarDecl *Param = + BuildParmVarDeclForTypedef(CurBlock->TheDecl, + ParamInfo.getLocStart(), + *I); + Params.push_back(Param); + } + } + + // Set the parameters on the block decl. + if (!Params.empty()) { + CurBlock->TheDecl->setParams(Params); + CheckParmsForFunctionDef(CurBlock->TheDecl->param_begin(), + CurBlock->TheDecl->param_end(), + /*CheckParameterNames=*/false); + } + + // Finally we can process decl attributes. + ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); + + // Put the parameter variables in scope. We can bail out immediately + // if we don't have any. + if (Params.empty()) + return; + + for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), + E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { + (*AI)->setOwningFunction(CurBlock->TheDecl); + + // If this has an identifier, add it to the scope stack. + if ((*AI)->getIdentifier()) { + CheckShadow(CurBlock->TheScope, *AI); + + PushOnScopeChains(*AI, CurBlock->TheScope); + } + } +} + +/// ActOnBlockError - If there is an error parsing a block, this callback +/// is invoked to pop the information about the block from the action impl. +void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { + // Leave the expression-evaluation context. + DiscardCleanupsInEvaluationContext(); + PopExpressionEvaluationContext(); + + // Pop off CurBlock, handle nested blocks. + PopDeclContext(); + PopFunctionScopeInfo(); +} + +/// ActOnBlockStmtExpr - This is called when the body of a block statement +/// literal was successfully completed. ^(int x){...} +ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, + Stmt *Body, Scope *CurScope) { + // If blocks are disabled, emit an error. + if (!LangOpts.Blocks) + Diag(CaretLoc, diag::err_blocks_disable); + + // Leave the expression-evaluation context. + if (hasAnyUnrecoverableErrorsInThisFunction()) + DiscardCleanupsInEvaluationContext(); + assert(!ExprNeedsCleanups && "cleanups within block not correctly bound!"); + PopExpressionEvaluationContext(); + + BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); + + PopDeclContext(); + + QualType RetTy = Context.VoidTy; + if (!BSI->ReturnType.isNull()) + RetTy = BSI->ReturnType; + + bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); + QualType BlockTy; + + // Set the captured variables on the block. + // FIXME: Share capture structure between BlockDecl and CapturingScopeInfo! + SmallVector<BlockDecl::Capture, 4> Captures; + for (unsigned i = 0, e = BSI->Captures.size(); i != e; i++) { + CapturingScopeInfo::Capture &Cap = BSI->Captures[i]; + if (Cap.isThisCapture()) + continue; + BlockDecl::Capture NewCap(Cap.getVariable(), Cap.isBlockCapture(), + Cap.isNested(), Cap.getCopyExpr()); + Captures.push_back(NewCap); + } + BSI->TheDecl->setCaptures(Context, Captures.begin(), Captures.end(), + BSI->CXXThisCaptureIndex != 0); + + // If the user wrote a function type in some form, try to use that. + if (!BSI->FunctionType.isNull()) { + const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>(); + + FunctionType::ExtInfo Ext = FTy->getExtInfo(); + if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true); + + // Turn protoless block types into nullary block types. + if (isa<FunctionNoProtoType>(FTy)) { + FunctionProtoType::ExtProtoInfo EPI; + EPI.ExtInfo = Ext; + BlockTy = Context.getFunctionType(RetTy, 0, 0, EPI); + + // Otherwise, if we don't need to change anything about the function type, + // preserve its sugar structure. + } else if (FTy->getResultType() == RetTy && + (!NoReturn || FTy->getNoReturnAttr())) { + BlockTy = BSI->FunctionType; + + // Otherwise, make the minimal modifications to the function type. + } else { + const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy); + FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo(); + EPI.TypeQuals = 0; // FIXME: silently? + EPI.ExtInfo = Ext; + BlockTy = Context.getFunctionType(RetTy, + FPT->arg_type_begin(), + FPT->getNumArgs(), + EPI); + } + + // If we don't have a function type, just build one from nothing. + } else { + FunctionProtoType::ExtProtoInfo EPI; + EPI.ExtInfo = FunctionType::ExtInfo().withNoReturn(NoReturn); + BlockTy = Context.getFunctionType(RetTy, 0, 0, EPI); + } + + DiagnoseUnusedParameters(BSI->TheDecl->param_begin(), + BSI->TheDecl->param_end()); + BlockTy = Context.getBlockPointerType(BlockTy); + + // If needed, diagnose invalid gotos and switches in the block. + if (getCurFunction()->NeedsScopeChecking() && + !hasAnyUnrecoverableErrorsInThisFunction()) + DiagnoseInvalidJumps(cast<CompoundStmt>(Body)); + + BSI->TheDecl->setBody(cast<CompoundStmt>(Body)); + + computeNRVO(Body, getCurBlock()); + + BlockExpr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy); + const AnalysisBasedWarnings::Policy &WP = AnalysisWarnings.getDefaultPolicy(); + PopFunctionScopeInfo(&WP, Result->getBlockDecl(), Result); + + // If the block isn't obviously global, i.e. it captures anything at + // all, then we need to do a few things in the surrounding context: + if (Result->getBlockDecl()->hasCaptures()) { + // First, this expression has a new cleanup object. + ExprCleanupObjects.push_back(Result->getBlockDecl()); + ExprNeedsCleanups = true; + + // It also gets a branch-protected scope if any of the captured + // variables needs destruction. + for (BlockDecl::capture_const_iterator + ci = Result->getBlockDecl()->capture_begin(), + ce = Result->getBlockDecl()->capture_end(); ci != ce; ++ci) { + const VarDecl *var = ci->getVariable(); + if (var->getType().isDestructedType() != QualType::DK_none) { + getCurFunction()->setHasBranchProtectedScope(); + break; + } + } + } + + return Owned(Result); +} + +ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, + Expr *E, ParsedType Ty, + SourceLocation RPLoc) { + TypeSourceInfo *TInfo; + GetTypeFromParser(Ty, &TInfo); + return BuildVAArgExpr(BuiltinLoc, E, TInfo, RPLoc); +} + +ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc, + Expr *E, TypeSourceInfo *TInfo, + SourceLocation RPLoc) { + Expr *OrigExpr = E; + + // Get the va_list type + QualType VaListType = Context.getBuiltinVaListType(); + if (VaListType->isArrayType()) { + // Deal with implicit array decay; for example, on x86-64, + // va_list is an array, but it's supposed to decay to + // a pointer for va_arg. + VaListType = Context.getArrayDecayedType(VaListType); + // Make sure the input expression also decays appropriately. + ExprResult Result = UsualUnaryConversions(E); + if (Result.isInvalid()) + return ExprError(); + E = Result.take(); + } else { + // Otherwise, the va_list argument must be an l-value because + // it is modified by va_arg. + if (!E->isTypeDependent() && + CheckForModifiableLvalue(E, BuiltinLoc, *this)) + return ExprError(); + } + + if (!E->isTypeDependent() && + !Context.hasSameType(VaListType, E->getType())) { + return ExprError(Diag(E->getLocStart(), + diag::err_first_argument_to_va_arg_not_of_type_va_list) + << OrigExpr->getType() << E->getSourceRange()); + } + + if (!TInfo->getType()->isDependentType()) { + if (RequireCompleteType(TInfo->getTypeLoc().getBeginLoc(), TInfo->getType(), + PDiag(diag::err_second_parameter_to_va_arg_incomplete) + << TInfo->getTypeLoc().getSourceRange())) + return ExprError(); + + if (RequireNonAbstractType(TInfo->getTypeLoc().getBeginLoc(), + TInfo->getType(), + PDiag(diag::err_second_parameter_to_va_arg_abstract) + << TInfo->getTypeLoc().getSourceRange())) + return ExprError(); + + if (!TInfo->getType().isPODType(Context)) { + Diag(TInfo->getTypeLoc().getBeginLoc(), + TInfo->getType()->isObjCLifetimeType() + ? diag::warn_second_parameter_to_va_arg_ownership_qualified + : diag::warn_second_parameter_to_va_arg_not_pod) + << TInfo->getType() + << TInfo->getTypeLoc().getSourceRange(); + } + + // Check for va_arg where arguments of the given type will be promoted + // (i.e. this va_arg is guaranteed to have undefined behavior). + QualType PromoteType; + if (TInfo->getType()->isPromotableIntegerType()) { + PromoteType = Context.getPromotedIntegerType(TInfo->getType()); + if (Context.typesAreCompatible(PromoteType, TInfo->getType())) + PromoteType = QualType(); + } + if (TInfo->getType()->isSpecificBuiltinType(BuiltinType::Float)) + PromoteType = Context.DoubleTy; + if (!PromoteType.isNull()) + Diag(TInfo->getTypeLoc().getBeginLoc(), + diag::warn_second_parameter_to_va_arg_never_compatible) + << TInfo->getType() + << PromoteType + << TInfo->getTypeLoc().getSourceRange(); + } + + QualType T = TInfo->getType().getNonLValueExprType(Context); + return Owned(new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T)); +} + +ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { + // The type of __null will be int or long, depending on the size of + // pointers on the target. + QualType Ty; + unsigned pw = Context.getTargetInfo().getPointerWidth(0); + if (pw == Context.getTargetInfo().getIntWidth()) + Ty = Context.IntTy; + else if (pw == Context.getTargetInfo().getLongWidth()) + Ty = Context.LongTy; + else if (pw == Context.getTargetInfo().getLongLongWidth()) + Ty = Context.LongLongTy; + else { + llvm_unreachable("I don't know size of pointer!"); + } + + return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); +} + +static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, + Expr *SrcExpr, FixItHint &Hint) { + if (!SemaRef.getLangOpts().ObjC1) + return; + + const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); + if (!PT) + return; + + // Check if the destination is of type 'id'. + if (!PT->isObjCIdType()) { + // Check if the destination is the 'NSString' interface. + const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); + if (!ID || !ID->getIdentifier()->isStr("NSString")) + return; + } + + // Ignore any parens, implicit casts (should only be + // array-to-pointer decays), and not-so-opaque values. The last is + // important for making this trigger for property assignments. + SrcExpr = SrcExpr->IgnoreParenImpCasts(); + if (OpaqueValueExpr *OV = dyn_cast<OpaqueValueExpr>(SrcExpr)) + if (OV->getSourceExpr()) + SrcExpr = OV->getSourceExpr()->IgnoreParenImpCasts(); + + StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr); + if (!SL || !SL->isAscii()) + return; + + Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); +} + +bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, + SourceLocation Loc, + QualType DstType, QualType SrcType, + Expr *SrcExpr, AssignmentAction Action, + bool *Complained) { + if (Complained) + *Complained = false; + + // Decode the result (notice that AST's are still created for extensions). + bool CheckInferredResultType = false; + bool isInvalid = false; + unsigned DiagKind = 0; + FixItHint Hint; + ConversionFixItGenerator ConvHints; + bool MayHaveConvFixit = false; + bool MayHaveFunctionDiff = false; + + switch (ConvTy) { + case Compatible: return false; + case PointerToInt: + DiagKind = diag::ext_typecheck_convert_pointer_int; + ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); + MayHaveConvFixit = true; + break; + case IntToPointer: + DiagKind = diag::ext_typecheck_convert_int_pointer; + ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); + MayHaveConvFixit = true; + break; + case IncompatiblePointer: + MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); + DiagKind = diag::ext_typecheck_convert_incompatible_pointer; + CheckInferredResultType = DstType->isObjCObjectPointerType() && + SrcType->isObjCObjectPointerType(); + if (Hint.isNull() && !CheckInferredResultType) { + ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); + } + MayHaveConvFixit = true; + break; + case IncompatiblePointerSign: + DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; + break; + case FunctionVoidPointer: + DiagKind = diag::ext_typecheck_convert_pointer_void_func; + break; + case IncompatiblePointerDiscardsQualifiers: { + // Perform array-to-pointer decay if necessary. + if (SrcType->isArrayType()) SrcType = Context.getArrayDecayedType(SrcType); + + Qualifiers lhq = SrcType->getPointeeType().getQualifiers(); + Qualifiers rhq = DstType->getPointeeType().getQualifiers(); + if (lhq.getAddressSpace() != rhq.getAddressSpace()) { + DiagKind = diag::err_typecheck_incompatible_address_space; + break; + + + } else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) { + DiagKind = diag::err_typecheck_incompatible_ownership; + break; + } + + llvm_unreachable("unknown error case for discarding qualifiers!"); + // fallthrough + } + case CompatiblePointerDiscardsQualifiers: + // If the qualifiers lost were because we were applying the + // (deprecated) C++ conversion from a string literal to a char* + // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: + // Ideally, this check would be performed in + // checkPointerTypesForAssignment. However, that would require a + // bit of refactoring (so that the second argument is an + // expression, rather than a type), which should be done as part + // of a larger effort to fix checkPointerTypesForAssignment for + // C++ semantics. + if (getLangOpts().CPlusPlus && + IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) + return false; + DiagKind = diag::ext_typecheck_convert_discards_qualifiers; + break; + case IncompatibleNestedPointerQualifiers: + DiagKind = diag::ext_nested_pointer_qualifier_mismatch; + break; + case IntToBlockPointer: + DiagKind = diag::err_int_to_block_pointer; + break; + case IncompatibleBlockPointer: + DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; + break; + case IncompatibleObjCQualifiedId: + // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since + // it can give a more specific diagnostic. + DiagKind = diag::warn_incompatible_qualified_id; + break; + case IncompatibleVectors: + DiagKind = diag::warn_incompatible_vectors; + break; + case IncompatibleObjCWeakRef: + DiagKind = diag::err_arc_weak_unavailable_assign; + break; + case Incompatible: + DiagKind = diag::err_typecheck_convert_incompatible; + ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); + MayHaveConvFixit = true; + isInvalid = true; + MayHaveFunctionDiff = true; + break; + } + + QualType FirstType, SecondType; + switch (Action) { + case AA_Assigning: + case AA_Initializing: + // The destination type comes first. + FirstType = DstType; + SecondType = SrcType; + break; + + case AA_Returning: + case AA_Passing: + case AA_Converting: + case AA_Sending: + case AA_Casting: + // The source type comes first. + FirstType = SrcType; + SecondType = DstType; + break; + } + + PartialDiagnostic FDiag = PDiag(DiagKind); + FDiag << FirstType << SecondType << Action << SrcExpr->getSourceRange(); + + // If we can fix the conversion, suggest the FixIts. + assert(ConvHints.isNull() || Hint.isNull()); + if (!ConvHints.isNull()) { + for (std::vector<FixItHint>::iterator HI = ConvHints.Hints.begin(), + HE = ConvHints.Hints.end(); HI != HE; ++HI) + FDiag << *HI; + } else { + FDiag << Hint; + } + if (MayHaveConvFixit) { FDiag << (unsigned) (ConvHints.Kind); } + + if (MayHaveFunctionDiff) + HandleFunctionTypeMismatch(FDiag, SecondType, FirstType); + + Diag(Loc, FDiag); + + if (SecondType == Context.OverloadTy) + NoteAllOverloadCandidates(OverloadExpr::find(SrcExpr).Expression, + FirstType); + + if (CheckInferredResultType) + EmitRelatedResultTypeNote(SrcExpr); + + if (Complained) + *Complained = true; + return isInvalid; +} + +ExprResult Sema::VerifyIntegerConstantExpression(Expr *E, + llvm::APSInt *Result) { + return VerifyIntegerConstantExpression(E, Result, + PDiag(diag::err_expr_not_ice) << LangOpts.CPlusPlus); +} + +ExprResult Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result, + PartialDiagnostic NotIceDiag, + bool AllowFold, + PartialDiagnostic FoldDiag) { + SourceLocation DiagLoc = E->getLocStart(); + + if (getLangOpts().CPlusPlus0x) { + // C++11 [expr.const]p5: + // If an expression of literal class type is used in a context where an + // integral constant expression is required, then that class type shall + // have a single non-explicit conversion function to an integral or + // unscoped enumeration type + ExprResult Converted; + if (NotIceDiag.getDiagID()) { + Converted = ConvertToIntegralOrEnumerationType( + DiagLoc, E, + PDiag(diag::err_ice_not_integral), + PDiag(diag::err_ice_incomplete_type), + PDiag(diag::err_ice_explicit_conversion), + PDiag(diag::note_ice_conversion_here), + PDiag(diag::err_ice_ambiguous_conversion), + PDiag(diag::note_ice_conversion_here), + PDiag(0), + /*AllowScopedEnumerations*/ false); + } else { + // The caller wants to silently enquire whether this is an ICE. Don't + // produce any diagnostics if it isn't. + Converted = ConvertToIntegralOrEnumerationType( + DiagLoc, E, PDiag(), PDiag(), PDiag(), PDiag(), + PDiag(), PDiag(), PDiag(), false); + } + if (Converted.isInvalid()) + return Converted; + E = Converted.take(); + if (!E->getType()->isIntegralOrUnscopedEnumerationType()) + return ExprError(); + } else if (!E->getType()->isIntegralOrUnscopedEnumerationType()) { + // An ICE must be of integral or unscoped enumeration type. + if (NotIceDiag.getDiagID()) + Diag(DiagLoc, NotIceDiag) << E->getSourceRange(); + return ExprError(); + } + + // Circumvent ICE checking in C++11 to avoid evaluating the expression twice + // in the non-ICE case. + if (!getLangOpts().CPlusPlus0x && E->isIntegerConstantExpr(Context)) { + if (Result) + *Result = E->EvaluateKnownConstInt(Context); + return Owned(E); + } + + Expr::EvalResult EvalResult; + llvm::SmallVector<PartialDiagnosticAt, 8> Notes; + EvalResult.Diag = &Notes; + + // Try to evaluate the expression, and produce diagnostics explaining why it's + // not a constant expression as a side-effect. + bool Folded = E->EvaluateAsRValue(EvalResult, Context) && + EvalResult.Val.isInt() && !EvalResult.HasSideEffects; + + // In C++11, we can rely on diagnostics being produced for any expression + // which is not a constant expression. If no diagnostics were produced, then + // this is a constant expression. + if (Folded && getLangOpts().CPlusPlus0x && Notes.empty()) { + if (Result) + *Result = EvalResult.Val.getInt(); + return Owned(E); + } + + // If our only note is the usual "invalid subexpression" note, just point + // the caret at its location rather than producing an essentially + // redundant note. + if (Notes.size() == 1 && Notes[0].second.getDiagID() == + diag::note_invalid_subexpr_in_const_expr) { + DiagLoc = Notes[0].first; + Notes.clear(); + } + + if (!Folded || !AllowFold) { + if (NotIceDiag.getDiagID()) { + Diag(DiagLoc, NotIceDiag) << E->getSourceRange(); + for (unsigned I = 0, N = Notes.size(); I != N; ++I) + Diag(Notes[I].first, Notes[I].second); + } + + return ExprError(); + } + + if (FoldDiag.getDiagID()) + Diag(DiagLoc, FoldDiag) << E->getSourceRange(); + else + Diag(DiagLoc, diag::ext_expr_not_ice) + << E->getSourceRange() << LangOpts.CPlusPlus; + for (unsigned I = 0, N = Notes.size(); I != N; ++I) + Diag(Notes[I].first, Notes[I].second); + + if (Result) + *Result = EvalResult.Val.getInt(); + return Owned(E); +} + +namespace { + // Handle the case where we conclude a expression which we speculatively + // considered to be unevaluated is actually evaluated. + class TransformToPE : public TreeTransform<TransformToPE> { + typedef TreeTransform<TransformToPE> BaseTransform; + + public: + TransformToPE(Sema &SemaRef) : BaseTransform(SemaRef) { } + + // Make sure we redo semantic analysis + bool AlwaysRebuild() { return true; } + + // Make sure we handle LabelStmts correctly. + // FIXME: This does the right thing, but maybe we need a more general + // fix to TreeTransform? + StmtResult TransformLabelStmt(LabelStmt *S) { + S->getDecl()->setStmt(0); + return BaseTransform::TransformLabelStmt(S); + } + + // We need to special-case DeclRefExprs referring to FieldDecls which + // are not part of a member pointer formation; normal TreeTransforming + // doesn't catch this case because of the way we represent them in the AST. + // FIXME: This is a bit ugly; is it really the best way to handle this + // case? + // + // Error on DeclRefExprs referring to FieldDecls. + ExprResult TransformDeclRefExpr(DeclRefExpr *E) { + if (isa<FieldDecl>(E->getDecl()) && + SemaRef.ExprEvalContexts.back().Context != Sema::Unevaluated) + return SemaRef.Diag(E->getLocation(), + diag::err_invalid_non_static_member_use) + << E->getDecl() << E->getSourceRange(); + + return BaseTransform::TransformDeclRefExpr(E); + } + + // Exception: filter out member pointer formation + ExprResult TransformUnaryOperator(UnaryOperator *E) { + if (E->getOpcode() == UO_AddrOf && E->getType()->isMemberPointerType()) + return E; + + return BaseTransform::TransformUnaryOperator(E); + } + + ExprResult TransformLambdaExpr(LambdaExpr *E) { + // Lambdas never need to be transformed. + return E; + } + }; +} + +ExprResult Sema::TranformToPotentiallyEvaluated(Expr *E) { + assert(ExprEvalContexts.back().Context == Unevaluated && + "Should only transform unevaluated expressions"); + ExprEvalContexts.back().Context = + ExprEvalContexts[ExprEvalContexts.size()-2].Context; + if (ExprEvalContexts.back().Context == Unevaluated) + return E; + return TransformToPE(*this).TransformExpr(E); +} + +void +Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext, + Decl *LambdaContextDecl, + bool IsDecltype) { + ExprEvalContexts.push_back( + ExpressionEvaluationContextRecord(NewContext, + ExprCleanupObjects.size(), + ExprNeedsCleanups, + LambdaContextDecl, + IsDecltype)); + ExprNeedsCleanups = false; + if (!MaybeODRUseExprs.empty()) + std::swap(MaybeODRUseExprs, ExprEvalContexts.back().SavedMaybeODRUseExprs); +} + +void Sema::PopExpressionEvaluationContext() { + ExpressionEvaluationContextRecord& Rec = ExprEvalContexts.back(); + + if (!Rec.Lambdas.empty()) { + if (Rec.Context == Unevaluated) { + // C++11 [expr.prim.lambda]p2: + // A lambda-expression shall not appear in an unevaluated operand + // (Clause 5). + for (unsigned I = 0, N = Rec.Lambdas.size(); I != N; ++I) + Diag(Rec.Lambdas[I]->getLocStart(), + diag::err_lambda_unevaluated_operand); + } else { + // Mark the capture expressions odr-used. This was deferred + // during lambda expression creation. + for (unsigned I = 0, N = Rec.Lambdas.size(); I != N; ++I) { + LambdaExpr *Lambda = Rec.Lambdas[I]; + for (LambdaExpr::capture_init_iterator + C = Lambda->capture_init_begin(), + CEnd = Lambda->capture_init_end(); + C != CEnd; ++C) { + MarkDeclarationsReferencedInExpr(*C); + } + } + } + } + + // When are coming out of an unevaluated context, clear out any + // temporaries that we may have created as part of the evaluation of + // the expression in that context: they aren't relevant because they + // will never be constructed. + if (Rec.Context == Unevaluated || Rec.Context == ConstantEvaluated) { + ExprCleanupObjects.erase(ExprCleanupObjects.begin() + Rec.NumCleanupObjects, + ExprCleanupObjects.end()); + ExprNeedsCleanups = Rec.ParentNeedsCleanups; + CleanupVarDeclMarking(); + std::swap(MaybeODRUseExprs, Rec.SavedMaybeODRUseExprs); + // Otherwise, merge the contexts together. + } else { + ExprNeedsCleanups |= Rec.ParentNeedsCleanups; + MaybeODRUseExprs.insert(Rec.SavedMaybeODRUseExprs.begin(), + Rec.SavedMaybeODRUseExprs.end()); + } + + // Pop the current expression evaluation context off the stack. + ExprEvalContexts.pop_back(); +} + +void Sema::DiscardCleanupsInEvaluationContext() { + ExprCleanupObjects.erase( + ExprCleanupObjects.begin() + ExprEvalContexts.back().NumCleanupObjects, + ExprCleanupObjects.end()); + ExprNeedsCleanups = false; + MaybeODRUseExprs.clear(); +} + +ExprResult Sema::HandleExprEvaluationContextForTypeof(Expr *E) { + if (!E->getType()->isVariablyModifiedType()) + return E; + return TranformToPotentiallyEvaluated(E); +} + +static bool IsPotentiallyEvaluatedContext(Sema &SemaRef) { + // Do not mark anything as "used" within a dependent context; wait for + // an instantiation. + if (SemaRef.CurContext->isDependentContext()) + return false; + + switch (SemaRef.ExprEvalContexts.back().Context) { + case Sema::Unevaluated: + // We are in an expression that is not potentially evaluated; do nothing. + // (Depending on how you read the standard, we actually do need to do + // something here for null pointer constants, but the standard's + // definition of a null pointer constant is completely crazy.) + return false; + + case Sema::ConstantEvaluated: + case Sema::PotentiallyEvaluated: + // We are in a potentially evaluated expression (or a constant-expression + // in C++03); we need to do implicit template instantiation, implicitly + // define class members, and mark most declarations as used. + return true; + + case Sema::PotentiallyEvaluatedIfUsed: + // Referenced declarations will only be used if the construct in the + // containing expression is used. + return false; + } + llvm_unreachable("Invalid context"); +} + +/// \brief Mark a function referenced, and check whether it is odr-used +/// (C++ [basic.def.odr]p2, C99 6.9p3) +void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func) { + assert(Func && "No function?"); + + Func->setReferenced(); + + // Don't mark this function as used multiple times, unless it's a constexpr + // function which we need to instantiate. + if (Func->isUsed(false) && + !(Func->isConstexpr() && !Func->getBody() && + Func->isImplicitlyInstantiable())) + return; + + if (!IsPotentiallyEvaluatedContext(*this)) + return; + + // Note that this declaration has been used. + if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Func)) { + if (Constructor->isDefaulted() && !Constructor->isDeleted()) { + if (Constructor->isDefaultConstructor()) { + if (Constructor->isTrivial()) + return; + if (!Constructor->isUsed(false)) + DefineImplicitDefaultConstructor(Loc, Constructor); + } else if (Constructor->isCopyConstructor()) { + if (!Constructor->isUsed(false)) + DefineImplicitCopyConstructor(Loc, Constructor); + } else if (Constructor->isMoveConstructor()) { + if (!Constructor->isUsed(false)) + DefineImplicitMoveConstructor(Loc, Constructor); + } + } + + MarkVTableUsed(Loc, Constructor->getParent()); + } else if (CXXDestructorDecl *Destructor = + dyn_cast<CXXDestructorDecl>(Func)) { + if (Destructor->isDefaulted() && !Destructor->isDeleted() && + !Destructor->isUsed(false)) + DefineImplicitDestructor(Loc, Destructor); + if (Destructor->isVirtual()) + MarkVTableUsed(Loc, Destructor->getParent()); + } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(Func)) { + if (MethodDecl->isDefaulted() && !MethodDecl->isDeleted() && + MethodDecl->isOverloadedOperator() && + MethodDecl->getOverloadedOperator() == OO_Equal) { + if (!MethodDecl->isUsed(false)) { + if (MethodDecl->isCopyAssignmentOperator()) + DefineImplicitCopyAssignment(Loc, MethodDecl); + else + DefineImplicitMoveAssignment(Loc, MethodDecl); + } + } else if (isa<CXXConversionDecl>(MethodDecl) && + MethodDecl->getParent()->isLambda()) { + CXXConversionDecl *Conversion = cast<CXXConversionDecl>(MethodDecl); + if (Conversion->isLambdaToBlockPointerConversion()) + DefineImplicitLambdaToBlockPointerConversion(Loc, Conversion); + else + DefineImplicitLambdaToFunctionPointerConversion(Loc, Conversion); + } else if (MethodDecl->isVirtual()) + MarkVTableUsed(Loc, MethodDecl->getParent()); + } + + // Recursive functions should be marked when used from another function. + // FIXME: Is this really right? + if (CurContext == Func) return; + + // Implicit instantiation of function templates and member functions of + // class templates. + if (Func->isImplicitlyInstantiable()) { + bool AlreadyInstantiated = false; + SourceLocation PointOfInstantiation = Loc; + if (FunctionTemplateSpecializationInfo *SpecInfo + = Func->getTemplateSpecializationInfo()) { + if (SpecInfo->getPointOfInstantiation().isInvalid()) + SpecInfo->setPointOfInstantiation(Loc); + else if (SpecInfo->getTemplateSpecializationKind() + == TSK_ImplicitInstantiation) { + AlreadyInstantiated = true; + PointOfInstantiation = SpecInfo->getPointOfInstantiation(); + } + } else if (MemberSpecializationInfo *MSInfo + = Func->getMemberSpecializationInfo()) { + if (MSInfo->getPointOfInstantiation().isInvalid()) + MSInfo->setPointOfInstantiation(Loc); + else if (MSInfo->getTemplateSpecializationKind() + == TSK_ImplicitInstantiation) { + AlreadyInstantiated = true; + PointOfInstantiation = MSInfo->getPointOfInstantiation(); + } + } + + if (!AlreadyInstantiated || Func->isConstexpr()) { + if (isa<CXXRecordDecl>(Func->getDeclContext()) && + cast<CXXRecordDecl>(Func->getDeclContext())->isLocalClass()) + PendingLocalImplicitInstantiations.push_back( + std::make_pair(Func, PointOfInstantiation)); + else if (Func->isConstexpr()) + // Do not defer instantiations of constexpr functions, to avoid the + // expression evaluator needing to call back into Sema if it sees a + // call to such a function. + InstantiateFunctionDefinition(PointOfInstantiation, Func); + else { + PendingInstantiations.push_back(std::make_pair(Func, + PointOfInstantiation)); + // Notify the consumer that a function was implicitly instantiated. + Consumer.HandleCXXImplicitFunctionInstantiation(Func); + } + } + } else { + // Walk redefinitions, as some of them may be instantiable. + for (FunctionDecl::redecl_iterator i(Func->redecls_begin()), + e(Func->redecls_end()); i != e; ++i) { + if (!i->isUsed(false) && i->isImplicitlyInstantiable()) + MarkFunctionReferenced(Loc, *i); + } + } + + // Keep track of used but undefined functions. + if (!Func->isPure() && !Func->hasBody() && + Func->getLinkage() != ExternalLinkage) { + SourceLocation &old = UndefinedInternals[Func->getCanonicalDecl()]; + if (old.isInvalid()) old = Loc; + } + + Func->setUsed(true); +} + +static void +diagnoseUncapturableValueReference(Sema &S, SourceLocation loc, + VarDecl *var, DeclContext *DC) { + DeclContext *VarDC = var->getDeclContext(); + + // If the parameter still belongs to the translation unit, then + // we're actually just using one parameter in the declaration of + // the next. + if (isa<ParmVarDecl>(var) && + isa<TranslationUnitDecl>(VarDC)) + return; + + // For C code, don't diagnose about capture if we're not actually in code + // right now; it's impossible to write a non-constant expression outside of + // function context, so we'll get other (more useful) diagnostics later. + // + // For C++, things get a bit more nasty... it would be nice to suppress this + // diagnostic for certain cases like using a local variable in an array bound + // for a member of a local class, but the correct predicate is not obvious. + if (!S.getLangOpts().CPlusPlus && !S.CurContext->isFunctionOrMethod()) + return; + + if (isa<CXXMethodDecl>(VarDC) && + cast<CXXRecordDecl>(VarDC->getParent())->isLambda()) { + S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_lambda) + << var->getIdentifier(); + } else if (FunctionDecl *fn = dyn_cast<FunctionDecl>(VarDC)) { + S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_function) + << var->getIdentifier() << fn->getDeclName(); + } else if (isa<BlockDecl>(VarDC)) { + S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_block) + << var->getIdentifier(); + } else { + // FIXME: Is there any other context where a local variable can be + // declared? + S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_context) + << var->getIdentifier(); + } + + S.Diag(var->getLocation(), diag::note_local_variable_declared_here) + << var->getIdentifier(); + + // FIXME: Add additional diagnostic info about class etc. which prevents + // capture. +} + +/// \brief Capture the given variable in the given lambda expression. +static ExprResult captureInLambda(Sema &S, LambdaScopeInfo *LSI, + VarDecl *Var, QualType FieldType, + QualType DeclRefType, + SourceLocation Loc) { + CXXRecordDecl *Lambda = LSI->Lambda; + + // Build the non-static data member. + FieldDecl *Field + = FieldDecl::Create(S.Context, Lambda, Loc, Loc, 0, FieldType, + S.Context.getTrivialTypeSourceInfo(FieldType, Loc), + 0, false, false); + Field->setImplicit(true); + Field->setAccess(AS_private); + Lambda->addDecl(Field); + + // C++11 [expr.prim.lambda]p21: + // When the lambda-expression is evaluated, the entities that + // are captured by copy are used to direct-initialize each + // corresponding non-static data member of the resulting closure + // object. (For array members, the array elements are + // direct-initialized in increasing subscript order.) These + // initializations are performed in the (unspecified) order in + // which the non-static data members are declared. + + // Introduce a new evaluation context for the initialization, so + // that temporaries introduced as part of the capture are retained + // to be re-"exported" from the lambda expression itself. + S.PushExpressionEvaluationContext(Sema::PotentiallyEvaluated); + + // C++ [expr.prim.labda]p12: + // An entity captured by a lambda-expression is odr-used (3.2) in + // the scope containing the lambda-expression. + Expr *Ref = new (S.Context) DeclRefExpr(Var, false, DeclRefType, + VK_LValue, Loc); + Var->setReferenced(true); + Var->setUsed(true); + + // When the field has array type, create index variables for each + // dimension of the array. We use these index variables to subscript + // the source array, and other clients (e.g., CodeGen) will perform + // the necessary iteration with these index variables. + SmallVector<VarDecl *, 4> IndexVariables; + QualType BaseType = FieldType; + QualType SizeType = S.Context.getSizeType(); + LSI->ArrayIndexStarts.push_back(LSI->ArrayIndexVars.size()); + while (const ConstantArrayType *Array + = S.Context.getAsConstantArrayType(BaseType)) { + // Create the iteration variable for this array index. + IdentifierInfo *IterationVarName = 0; + { + SmallString<8> Str; + llvm::raw_svector_ostream OS(Str); + OS << "__i" << IndexVariables.size(); + IterationVarName = &S.Context.Idents.get(OS.str()); + } + VarDecl *IterationVar + = VarDecl::Create(S.Context, S.CurContext, Loc, Loc, + IterationVarName, SizeType, + S.Context.getTrivialTypeSourceInfo(SizeType, Loc), + SC_None, SC_None); + IndexVariables.push_back(IterationVar); + LSI->ArrayIndexVars.push_back(IterationVar); + + // Create a reference to the iteration variable. + ExprResult IterationVarRef + = S.BuildDeclRefExpr(IterationVar, SizeType, VK_LValue, Loc); + assert(!IterationVarRef.isInvalid() && + "Reference to invented variable cannot fail!"); + IterationVarRef = S.DefaultLvalueConversion(IterationVarRef.take()); + assert(!IterationVarRef.isInvalid() && + "Conversion of invented variable cannot fail!"); + + // Subscript the array with this iteration variable. + ExprResult Subscript = S.CreateBuiltinArraySubscriptExpr( + Ref, Loc, IterationVarRef.take(), Loc); + if (Subscript.isInvalid()) { + S.CleanupVarDeclMarking(); + S.DiscardCleanupsInEvaluationContext(); + S.PopExpressionEvaluationContext(); + return ExprError(); + } + + Ref = Subscript.take(); + BaseType = Array->getElementType(); + } + + // Construct the entity that we will be initializing. For an array, this + // will be first element in the array, which may require several levels + // of array-subscript entities. + SmallVector<InitializedEntity, 4> Entities; + Entities.reserve(1 + IndexVariables.size()); + Entities.push_back( + InitializedEntity::InitializeLambdaCapture(Var, Field, Loc)); + for (unsigned I = 0, N = IndexVariables.size(); I != N; ++I) + Entities.push_back(InitializedEntity::InitializeElement(S.Context, + 0, + Entities.back())); + + InitializationKind InitKind + = InitializationKind::CreateDirect(Loc, Loc, Loc); + InitializationSequence Init(S, Entities.back(), InitKind, &Ref, 1); + ExprResult Result(true); + if (!Init.Diagnose(S, Entities.back(), InitKind, &Ref, 1)) + Result = Init.Perform(S, Entities.back(), InitKind, + MultiExprArg(S, &Ref, 1)); + + // If this initialization requires any cleanups (e.g., due to a + // default argument to a copy constructor), note that for the + // lambda. + if (S.ExprNeedsCleanups) + LSI->ExprNeedsCleanups = true; + + // Exit the expression evaluation context used for the capture. + S.CleanupVarDeclMarking(); + S.DiscardCleanupsInEvaluationContext(); + S.PopExpressionEvaluationContext(); + return Result; +} + +bool Sema::tryCaptureVariable(VarDecl *Var, SourceLocation Loc, + TryCaptureKind Kind, SourceLocation EllipsisLoc, + bool BuildAndDiagnose, + QualType &CaptureType, + QualType &DeclRefType) { + bool Nested = false; + + DeclContext *DC = CurContext; + if (Var->getDeclContext() == DC) return true; + if (!Var->hasLocalStorage()) return true; + + bool HasBlocksAttr = Var->hasAttr<BlocksAttr>(); + + // Walk up the stack to determine whether we can capture the variable, + // performing the "simple" checks that don't depend on type. We stop when + // we've either hit the declared scope of the variable or find an existing + // capture of that variable. + CaptureType = Var->getType(); + DeclRefType = CaptureType.getNonReferenceType(); + bool Explicit = (Kind != TryCapture_Implicit); + unsigned FunctionScopesIndex = FunctionScopes.size() - 1; + do { + // Only block literals and lambda expressions can capture; other + // scopes don't work. + DeclContext *ParentDC; + if (isa<BlockDecl>(DC)) + ParentDC = DC->getParent(); + else if (isa<CXXMethodDecl>(DC) && + cast<CXXMethodDecl>(DC)->getOverloadedOperator() == OO_Call && + cast<CXXRecordDecl>(DC->getParent())->isLambda()) + ParentDC = DC->getParent()->getParent(); + else { + if (BuildAndDiagnose) + diagnoseUncapturableValueReference(*this, Loc, Var, DC); + return true; + } + + CapturingScopeInfo *CSI = + cast<CapturingScopeInfo>(FunctionScopes[FunctionScopesIndex]); + + // Check whether we've already captured it. + if (CSI->CaptureMap.count(Var)) { + // If we found a capture, any subcaptures are nested. + Nested = true; + + // Retrieve the capture type for this variable. + CaptureType = CSI->getCapture(Var).getCaptureType(); + + // Compute the type of an expression that refers to this variable. + DeclRefType = CaptureType.getNonReferenceType(); + + const CapturingScopeInfo::Capture &Cap = CSI->getCapture(Var); + if (Cap.isCopyCapture() && + !(isa<LambdaScopeInfo>(CSI) && cast<LambdaScopeInfo>(CSI)->Mutable)) + DeclRefType.addConst(); + break; + } + + bool IsBlock = isa<BlockScopeInfo>(CSI); + bool IsLambda = !IsBlock; + + // Lambdas are not allowed to capture unnamed variables + // (e.g. anonymous unions). + // FIXME: The C++11 rule don't actually state this explicitly, but I'm + // assuming that's the intent. + if (IsLambda && !Var->getDeclName()) { + if (BuildAndDiagnose) { + Diag(Loc, diag::err_lambda_capture_anonymous_var); + Diag(Var->getLocation(), diag::note_declared_at); + } + return true; + } + + // Prohibit variably-modified types; they're difficult to deal with. + if (Var->getType()->isVariablyModifiedType()) { + if (BuildAndDiagnose) { + if (IsBlock) + Diag(Loc, diag::err_ref_vm_type); + else + Diag(Loc, diag::err_lambda_capture_vm_type) << Var->getDeclName(); + Diag(Var->getLocation(), diag::note_previous_decl) + << Var->getDeclName(); + } + return true; + } + + // Lambdas are not allowed to capture __block variables; they don't + // support the expected semantics. + if (IsLambda && HasBlocksAttr) { + if (BuildAndDiagnose) { + Diag(Loc, diag::err_lambda_capture_block) + << Var->getDeclName(); + Diag(Var->getLocation(), diag::note_previous_decl) + << Var->getDeclName(); + } + return true; + } + + if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None && !Explicit) { + // No capture-default + if (BuildAndDiagnose) { + Diag(Loc, diag::err_lambda_impcap) << Var->getDeclName(); + Diag(Var->getLocation(), diag::note_previous_decl) + << Var->getDeclName(); + Diag(cast<LambdaScopeInfo>(CSI)->Lambda->getLocStart(), + diag::note_lambda_decl); + } + return true; + } + + FunctionScopesIndex--; + DC = ParentDC; + Explicit = false; + } while (!Var->getDeclContext()->Equals(DC)); + + // Walk back down the scope stack, computing the type of the capture at + // each step, checking type-specific requirements, and adding captures if + // requested. + for (unsigned I = ++FunctionScopesIndex, N = FunctionScopes.size(); I != N; + ++I) { + CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[I]); + + // Compute the type of the capture and of a reference to the capture within + // this scope. + if (isa<BlockScopeInfo>(CSI)) { + Expr *CopyExpr = 0; + bool ByRef = false; + + // Blocks are not allowed to capture arrays. + if (CaptureType->isArrayType()) { + if (BuildAndDiagnose) { + Diag(Loc, diag::err_ref_array_type); + Diag(Var->getLocation(), diag::note_previous_decl) + << Var->getDeclName(); + } + return true; + } + + // Forbid the block-capture of autoreleasing variables. + if (CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) { + if (BuildAndDiagnose) { + Diag(Loc, diag::err_arc_autoreleasing_capture) + << /*block*/ 0; + Diag(Var->getLocation(), diag::note_previous_decl) + << Var->getDeclName(); + } + return true; + } + + if (HasBlocksAttr || CaptureType->isReferenceType()) { + // Block capture by reference does not change the capture or + // declaration reference types. + ByRef = true; + } else { + // Block capture by copy introduces 'const'. + CaptureType = CaptureType.getNonReferenceType().withConst(); + DeclRefType = CaptureType; + + if (getLangOpts().CPlusPlus && BuildAndDiagnose) { + if (const RecordType *Record = DeclRefType->getAs<RecordType>()) { + // The capture logic needs the destructor, so make sure we mark it. + // Usually this is unnecessary because most local variables have + // their destructors marked at declaration time, but parameters are + // an exception because it's technically only the call site that + // actually requires the destructor. + if (isa<ParmVarDecl>(Var)) + FinalizeVarWithDestructor(Var, Record); + + // According to the blocks spec, the capture of a variable from + // the stack requires a const copy constructor. This is not true + // of the copy/move done to move a __block variable to the heap. + Expr *DeclRef = new (Context) DeclRefExpr(Var, false, + DeclRefType.withConst(), + VK_LValue, Loc); + ExprResult Result + = PerformCopyInitialization( + InitializedEntity::InitializeBlock(Var->getLocation(), + CaptureType, false), + Loc, Owned(DeclRef)); + + // Build a full-expression copy expression if initialization + // succeeded and used a non-trivial constructor. Recover from + // errors by pretending that the copy isn't necessary. + if (!Result.isInvalid() && + !cast<CXXConstructExpr>(Result.get())->getConstructor() + ->isTrivial()) { + Result = MaybeCreateExprWithCleanups(Result); + CopyExpr = Result.take(); + } + } + } + } + + // Actually capture the variable. + if (BuildAndDiagnose) + CSI->addCapture(Var, HasBlocksAttr, ByRef, Nested, Loc, + SourceLocation(), CaptureType, CopyExpr); + Nested = true; + continue; + } + + LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(CSI); + + // Determine whether we are capturing by reference or by value. + bool ByRef = false; + if (I == N - 1 && Kind != TryCapture_Implicit) { + ByRef = (Kind == TryCapture_ExplicitByRef); + } else { + ByRef = (LSI->ImpCaptureStyle == LambdaScopeInfo::ImpCap_LambdaByref); + } + + // Compute the type of the field that will capture this variable. + if (ByRef) { + // C++11 [expr.prim.lambda]p15: + // An entity is captured by reference if it is implicitly or + // explicitly captured but not captured by copy. It is + // unspecified whether additional unnamed non-static data + // members are declared in the closure type for entities + // captured by reference. + // + // FIXME: It is not clear whether we want to build an lvalue reference + // to the DeclRefType or to CaptureType.getNonReferenceType(). GCC appears + // to do the former, while EDG does the latter. Core issue 1249 will + // clarify, but for now we follow GCC because it's a more permissive and + // easily defensible position. + CaptureType = Context.getLValueReferenceType(DeclRefType); + } else { + // C++11 [expr.prim.lambda]p14: + // For each entity captured by copy, an unnamed non-static + // data member is declared in the closure type. The + // declaration order of these members is unspecified. The type + // of such a data member is the type of the corresponding + // captured entity if the entity is not a reference to an + // object, or the referenced type otherwise. [Note: If the + // captured entity is a reference to a function, the + // corresponding data member is also a reference to a + // function. - end note ] + if (const ReferenceType *RefType = CaptureType->getAs<ReferenceType>()){ + if (!RefType->getPointeeType()->isFunctionType()) + CaptureType = RefType->getPointeeType(); + } + + // Forbid the lambda copy-capture of autoreleasing variables. + if (CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) { + if (BuildAndDiagnose) { + Diag(Loc, diag::err_arc_autoreleasing_capture) << /*lambda*/ 1; + Diag(Var->getLocation(), diag::note_previous_decl) + << Var->getDeclName(); + } + return true; + } + } + + // Capture this variable in the lambda. + Expr *CopyExpr = 0; + if (BuildAndDiagnose) { + ExprResult Result = captureInLambda(*this, LSI, Var, CaptureType, + DeclRefType, Loc); + if (!Result.isInvalid()) + CopyExpr = Result.take(); + } + + // Compute the type of a reference to this captured variable. + if (ByRef) + DeclRefType = CaptureType.getNonReferenceType(); + else { + // C++ [expr.prim.lambda]p5: + // The closure type for a lambda-expression has a public inline + // function call operator [...]. This function call operator is + // declared const (9.3.1) if and only if the lambda-expression’s + // parameter-declaration-clause is not followed by mutable. + DeclRefType = CaptureType.getNonReferenceType(); + if (!LSI->Mutable && !CaptureType->isReferenceType()) + DeclRefType.addConst(); + } + + // Add the capture. + if (BuildAndDiagnose) + CSI->addCapture(Var, /*IsBlock=*/false, ByRef, Nested, Loc, + EllipsisLoc, CaptureType, CopyExpr); + Nested = true; + } + + return false; +} + +bool Sema::tryCaptureVariable(VarDecl *Var, SourceLocation Loc, + TryCaptureKind Kind, SourceLocation EllipsisLoc) { + QualType CaptureType; + QualType DeclRefType; + return tryCaptureVariable(Var, Loc, Kind, EllipsisLoc, + /*BuildAndDiagnose=*/true, CaptureType, + DeclRefType); +} + +QualType Sema::getCapturedDeclRefType(VarDecl *Var, SourceLocation Loc) { + QualType CaptureType; + QualType DeclRefType; + + // Determine whether we can capture this variable. + if (tryCaptureVariable(Var, Loc, TryCapture_Implicit, SourceLocation(), + /*BuildAndDiagnose=*/false, CaptureType, DeclRefType)) + return QualType(); + + return DeclRefType; +} + +static void MarkVarDeclODRUsed(Sema &SemaRef, VarDecl *Var, + SourceLocation Loc) { + // Keep track of used but undefined variables. + // FIXME: We shouldn't suppress this warning for static data members. + if (Var->hasDefinition(SemaRef.Context) == VarDecl::DeclarationOnly && + Var->getLinkage() != ExternalLinkage && + !(Var->isStaticDataMember() && Var->hasInit())) { + SourceLocation &old = SemaRef.UndefinedInternals[Var->getCanonicalDecl()]; + if (old.isInvalid()) old = Loc; + } + + SemaRef.tryCaptureVariable(Var, Loc); + + Var->setUsed(true); +} + +void Sema::UpdateMarkingForLValueToRValue(Expr *E) { + // Per C++11 [basic.def.odr], a variable is odr-used "unless it is + // an object that satisfies the requirements for appearing in a + // constant expression (5.19) and the lvalue-to-rvalue conversion (4.1) + // is immediately applied." This function handles the lvalue-to-rvalue + // conversion part. + MaybeODRUseExprs.erase(E->IgnoreParens()); +} + +ExprResult Sema::ActOnConstantExpression(ExprResult Res) { + if (!Res.isUsable()) + return Res; + + // If a constant-expression is a reference to a variable where we delay + // deciding whether it is an odr-use, just assume we will apply the + // lvalue-to-rvalue conversion. In the one case where this doesn't happen + // (a non-type template argument), we have special handling anyway. + UpdateMarkingForLValueToRValue(Res.get()); + return Res; +} + +void Sema::CleanupVarDeclMarking() { + for (llvm::SmallPtrSetIterator<Expr*> i = MaybeODRUseExprs.begin(), + e = MaybeODRUseExprs.end(); + i != e; ++i) { + VarDecl *Var; + SourceLocation Loc; + if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(*i)) { + Var = cast<VarDecl>(DRE->getDecl()); + Loc = DRE->getLocation(); + } else if (MemberExpr *ME = dyn_cast<MemberExpr>(*i)) { + Var = cast<VarDecl>(ME->getMemberDecl()); + Loc = ME->getMemberLoc(); + } else { + llvm_unreachable("Unexpcted expression"); + } + + MarkVarDeclODRUsed(*this, Var, Loc); + } + + MaybeODRUseExprs.clear(); +} + +// Mark a VarDecl referenced, and perform the necessary handling to compute +// odr-uses. +static void DoMarkVarDeclReferenced(Sema &SemaRef, SourceLocation Loc, + VarDecl *Var, Expr *E) { + Var->setReferenced(); + + if (!IsPotentiallyEvaluatedContext(SemaRef)) + return; + + // Implicit instantiation of static data members of class templates. + if (Var->isStaticDataMember() && Var->getInstantiatedFromStaticDataMember()) { + MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); + assert(MSInfo && "Missing member specialization information?"); + bool AlreadyInstantiated = !MSInfo->getPointOfInstantiation().isInvalid(); + if (MSInfo->getTemplateSpecializationKind() == TSK_ImplicitInstantiation && + (!AlreadyInstantiated || + Var->isUsableInConstantExpressions(SemaRef.Context))) { + if (!AlreadyInstantiated) { + // This is a modification of an existing AST node. Notify listeners. + if (ASTMutationListener *L = SemaRef.getASTMutationListener()) + L->StaticDataMemberInstantiated(Var); + MSInfo->setPointOfInstantiation(Loc); + } + SourceLocation PointOfInstantiation = MSInfo->getPointOfInstantiation(); + if (Var->isUsableInConstantExpressions(SemaRef.Context)) + // Do not defer instantiations of variables which could be used in a + // constant expression. + SemaRef.InstantiateStaticDataMemberDefinition(PointOfInstantiation,Var); + else + SemaRef.PendingInstantiations.push_back( + std::make_pair(Var, PointOfInstantiation)); + } + } + + // Per C++11 [basic.def.odr], a variable is odr-used "unless it is + // an object that satisfies the requirements for appearing in a + // constant expression (5.19) and the lvalue-to-rvalue conversion (4.1) + // is immediately applied." We check the first part here, and + // Sema::UpdateMarkingForLValueToRValue deals with the second part. + // Note that we use the C++11 definition everywhere because nothing in + // C++03 depends on whether we get the C++03 version correct. This does not + // apply to references, since they are not objects. + const VarDecl *DefVD; + if (E && !isa<ParmVarDecl>(Var) && !Var->getType()->isReferenceType() && + Var->isUsableInConstantExpressions(SemaRef.Context) && + Var->getAnyInitializer(DefVD) && DefVD->checkInitIsICE()) + SemaRef.MaybeODRUseExprs.insert(E); + else + MarkVarDeclODRUsed(SemaRef, Var, Loc); +} + +/// \brief Mark a variable referenced, and check whether it is odr-used +/// (C++ [basic.def.odr]p2, C99 6.9p3). Note that this should not be +/// used directly for normal expressions referring to VarDecl. +void Sema::MarkVariableReferenced(SourceLocation Loc, VarDecl *Var) { + DoMarkVarDeclReferenced(*this, Loc, Var, 0); +} + +static void MarkExprReferenced(Sema &SemaRef, SourceLocation Loc, + Decl *D, Expr *E) { + if (VarDecl *Var = dyn_cast<VarDecl>(D)) { + DoMarkVarDeclReferenced(SemaRef, Loc, Var, E); + return; + } + + SemaRef.MarkAnyDeclReferenced(Loc, D); +} + +/// \brief Perform reference-marking and odr-use handling for a DeclRefExpr. +void Sema::MarkDeclRefReferenced(DeclRefExpr *E) { + MarkExprReferenced(*this, E->getLocation(), E->getDecl(), E); +} + +/// \brief Perform reference-marking and odr-use handling for a MemberExpr. +void Sema::MarkMemberReferenced(MemberExpr *E) { + MarkExprReferenced(*this, E->getMemberLoc(), E->getMemberDecl(), E); +} + +/// \brief Perform marking for a reference to an arbitrary declaration. It +/// marks the declaration referenced, and performs odr-use checking for functions +/// and variables. This method should not be used when building an normal +/// expression which refers to a variable. +void Sema::MarkAnyDeclReferenced(SourceLocation Loc, Decl *D) { + if (VarDecl *VD = dyn_cast<VarDecl>(D)) + MarkVariableReferenced(Loc, VD); + else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) + MarkFunctionReferenced(Loc, FD); + else + D->setReferenced(); +} + +namespace { + // Mark all of the declarations referenced + // FIXME: Not fully implemented yet! We need to have a better understanding + // of when we're entering + class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { + Sema &S; + SourceLocation Loc; + + public: + typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; + + MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } + + bool TraverseTemplateArgument(const TemplateArgument &Arg); + bool TraverseRecordType(RecordType *T); + }; +} + +bool MarkReferencedDecls::TraverseTemplateArgument( + const TemplateArgument &Arg) { + if (Arg.getKind() == TemplateArgument::Declaration) { + if (Decl *D = Arg.getAsDecl()) + S.MarkAnyDeclReferenced(Loc, D); + } + + return Inherited::TraverseTemplateArgument(Arg); +} + +bool MarkReferencedDecls::TraverseRecordType(RecordType *T) { + if (ClassTemplateSpecializationDecl *Spec + = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { + const TemplateArgumentList &Args = Spec->getTemplateArgs(); + return TraverseTemplateArguments(Args.data(), Args.size()); + } + + return true; +} + +void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { + MarkReferencedDecls Marker(*this, Loc); + Marker.TraverseType(Context.getCanonicalType(T)); +} + +namespace { + /// \brief Helper class that marks all of the declarations referenced by + /// potentially-evaluated subexpressions as "referenced". + class EvaluatedExprMarker : public EvaluatedExprVisitor<EvaluatedExprMarker> { + Sema &S; + bool SkipLocalVariables; + + public: + typedef EvaluatedExprVisitor<EvaluatedExprMarker> Inherited; + + EvaluatedExprMarker(Sema &S, bool SkipLocalVariables) + : Inherited(S.Context), S(S), SkipLocalVariables(SkipLocalVariables) { } + + void VisitDeclRefExpr(DeclRefExpr *E) { + // If we were asked not to visit local variables, don't. + if (SkipLocalVariables) { + if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl())) + if (VD->hasLocalStorage()) + return; + } + + S.MarkDeclRefReferenced(E); + } + + void VisitMemberExpr(MemberExpr *E) { + S.MarkMemberReferenced(E); + Inherited::VisitMemberExpr(E); + } + + void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) { + S.MarkFunctionReferenced(E->getLocStart(), + const_cast<CXXDestructorDecl*>(E->getTemporary()->getDestructor())); + Visit(E->getSubExpr()); + } + + void VisitCXXNewExpr(CXXNewExpr *E) { + if (E->getOperatorNew()) + S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorNew()); + if (E->getOperatorDelete()) + S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorDelete()); + Inherited::VisitCXXNewExpr(E); + } + + void VisitCXXDeleteExpr(CXXDeleteExpr *E) { + if (E->getOperatorDelete()) + S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorDelete()); + QualType Destroyed = S.Context.getBaseElementType(E->getDestroyedType()); + if (const RecordType *DestroyedRec = Destroyed->getAs<RecordType>()) { + CXXRecordDecl *Record = cast<CXXRecordDecl>(DestroyedRec->getDecl()); + S.MarkFunctionReferenced(E->getLocStart(), + S.LookupDestructor(Record)); + } + + Inherited::VisitCXXDeleteExpr(E); + } + + void VisitCXXConstructExpr(CXXConstructExpr *E) { + S.MarkFunctionReferenced(E->getLocStart(), E->getConstructor()); + Inherited::VisitCXXConstructExpr(E); + } + + void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) { + Visit(E->getExpr()); + } + + void VisitImplicitCastExpr(ImplicitCastExpr *E) { + Inherited::VisitImplicitCastExpr(E); + + if (E->getCastKind() == CK_LValueToRValue) + S.UpdateMarkingForLValueToRValue(E->getSubExpr()); + } + }; +} + +/// \brief Mark any declarations that appear within this expression or any +/// potentially-evaluated subexpressions as "referenced". +/// +/// \param SkipLocalVariables If true, don't mark local variables as +/// 'referenced'. +void Sema::MarkDeclarationsReferencedInExpr(Expr *E, + bool SkipLocalVariables) { + EvaluatedExprMarker(*this, SkipLocalVariables).Visit(E); +} + +/// \brief Emit a diagnostic that describes an effect on the run-time behavior +/// of the program being compiled. +/// +/// This routine emits the given diagnostic when the code currently being +/// type-checked is "potentially evaluated", meaning that there is a +/// possibility that the code will actually be executable. Code in sizeof() +/// expressions, code used only during overload resolution, etc., are not +/// potentially evaluated. This routine will suppress such diagnostics or, +/// in the absolutely nutty case of potentially potentially evaluated +/// expressions (C++ typeid), queue the diagnostic to potentially emit it +/// later. +/// +/// This routine should be used for all diagnostics that describe the run-time +/// behavior of a program, such as passing a non-POD value through an ellipsis. +/// Failure to do so will likely result in spurious diagnostics or failures +/// during overload resolution or within sizeof/alignof/typeof/typeid. +bool Sema::DiagRuntimeBehavior(SourceLocation Loc, const Stmt *Statement, + const PartialDiagnostic &PD) { + switch (ExprEvalContexts.back().Context) { + case Unevaluated: + // The argument will never be evaluated, so don't complain. + break; + + case ConstantEvaluated: + // Relevant diagnostics should be produced by constant evaluation. + break; + + case PotentiallyEvaluated: + case PotentiallyEvaluatedIfUsed: + if (Statement && getCurFunctionOrMethodDecl()) { + FunctionScopes.back()->PossiblyUnreachableDiags. + push_back(sema::PossiblyUnreachableDiag(PD, Loc, Statement)); + } + else + Diag(Loc, PD); + + return true; + } + + return false; +} + +bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, + CallExpr *CE, FunctionDecl *FD) { + if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) + return false; + + // If we're inside a decltype's expression, don't check for a valid return + // type or construct temporaries until we know whether this is the last call. + if (ExprEvalContexts.back().IsDecltype) { + ExprEvalContexts.back().DelayedDecltypeCalls.push_back(CE); + return false; + } + + PartialDiagnostic Note = + FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) + << FD->getDeclName() : PDiag(); + SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); + + if (RequireCompleteType(Loc, ReturnType, + FD ? + PDiag(diag::err_call_function_incomplete_return) + << CE->getSourceRange() << FD->getDeclName() : + PDiag(diag::err_call_incomplete_return) + << CE->getSourceRange(), + std::make_pair(NoteLoc, Note))) + return true; + + return false; +} + +// Diagnose the s/=/==/ and s/\|=/!=/ typos. Note that adding parentheses +// will prevent this condition from triggering, which is what we want. +void Sema::DiagnoseAssignmentAsCondition(Expr *E) { + SourceLocation Loc; + + unsigned diagnostic = diag::warn_condition_is_assignment; + bool IsOrAssign = false; + + if (BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) { + if (Op->getOpcode() != BO_Assign && Op->getOpcode() != BO_OrAssign) + return; + + IsOrAssign = Op->getOpcode() == BO_OrAssign; + + // Greylist some idioms by putting them into a warning subcategory. + if (ObjCMessageExpr *ME + = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { + Selector Sel = ME->getSelector(); + + // self = [<foo> init...] + if (isSelfExpr(Op->getLHS()) && Sel.getNameForSlot(0).startswith("init")) + diagnostic = diag::warn_condition_is_idiomatic_assignment; + + // <foo> = [<bar> nextObject] + else if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "nextObject") + diagnostic = diag::warn_condition_is_idiomatic_assignment; + } + + Loc = Op->getOperatorLoc(); + } else if (CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) { + if (Op->getOperator() != OO_Equal && Op->getOperator() != OO_PipeEqual) + return; + + IsOrAssign = Op->getOperator() == OO_PipeEqual; + Loc = Op->getOperatorLoc(); + } else { + // Not an assignment. + return; + } + + Diag(Loc, diagnostic) << E->getSourceRange(); + + SourceLocation Open = E->getLocStart(); + SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); + Diag(Loc, diag::note_condition_assign_silence) + << FixItHint::CreateInsertion(Open, "(") + << FixItHint::CreateInsertion(Close, ")"); + + if (IsOrAssign) + Diag(Loc, diag::note_condition_or_assign_to_comparison) + << FixItHint::CreateReplacement(Loc, "!="); + else + Diag(Loc, diag::note_condition_assign_to_comparison) + << FixItHint::CreateReplacement(Loc, "=="); +} + +/// \brief Redundant parentheses over an equality comparison can indicate +/// that the user intended an assignment used as condition. +void Sema::DiagnoseEqualityWithExtraParens(ParenExpr *ParenE) { + // Don't warn if the parens came from a macro. + SourceLocation parenLoc = ParenE->getLocStart(); + if (parenLoc.isInvalid() || parenLoc.isMacroID()) + return; + // Don't warn for dependent expressions. + if (ParenE->isTypeDependent()) + return; + + Expr *E = ParenE->IgnoreParens(); + + if (BinaryOperator *opE = dyn_cast<BinaryOperator>(E)) + if (opE->getOpcode() == BO_EQ && + opE->getLHS()->IgnoreParenImpCasts()->isModifiableLvalue(Context) + == Expr::MLV_Valid) { + SourceLocation Loc = opE->getOperatorLoc(); + + Diag(Loc, diag::warn_equality_with_extra_parens) << E->getSourceRange(); + SourceRange ParenERange = ParenE->getSourceRange(); + Diag(Loc, diag::note_equality_comparison_silence) + << FixItHint::CreateRemoval(ParenERange.getBegin()) + << FixItHint::CreateRemoval(ParenERange.getEnd()); + Diag(Loc, diag::note_equality_comparison_to_assign) + << FixItHint::CreateReplacement(Loc, "="); + } +} + +ExprResult Sema::CheckBooleanCondition(Expr *E, SourceLocation Loc) { + DiagnoseAssignmentAsCondition(E); + if (ParenExpr *parenE = dyn_cast<ParenExpr>(E)) + DiagnoseEqualityWithExtraParens(parenE); + + ExprResult result = CheckPlaceholderExpr(E); + if (result.isInvalid()) return ExprError(); + E = result.take(); + + if (!E->isTypeDependent()) { + if (getLangOpts().CPlusPlus) + return CheckCXXBooleanCondition(E); // C++ 6.4p4 + + ExprResult ERes = DefaultFunctionArrayLvalueConversion(E); + if (ERes.isInvalid()) + return ExprError(); + E = ERes.take(); + + QualType T = E->getType(); + if (!T->isScalarType()) { // C99 6.8.4.1p1 + Diag(Loc, diag::err_typecheck_statement_requires_scalar) + << T << E->getSourceRange(); + return ExprError(); + } + } + + return Owned(E); +} + +ExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, + Expr *SubExpr) { + if (!SubExpr) + return ExprError(); + + return CheckBooleanCondition(SubExpr, Loc); +} + +namespace { + /// A visitor for rebuilding a call to an __unknown_any expression + /// to have an appropriate type. + struct RebuildUnknownAnyFunction + : StmtVisitor<RebuildUnknownAnyFunction, ExprResult> { + + Sema &S; + + RebuildUnknownAnyFunction(Sema &S) : S(S) {} + + ExprResult VisitStmt(Stmt *S) { + llvm_unreachable("unexpected statement!"); + } + + ExprResult VisitExpr(Expr *E) { + S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_call) + << E->getSourceRange(); + return ExprError(); + } + + /// Rebuild an expression which simply semantically wraps another + /// expression which it shares the type and value kind of. + template <class T> ExprResult rebuildSugarExpr(T *E) { + ExprResult SubResult = Visit(E->getSubExpr()); + if (SubResult.isInvalid()) return ExprError(); + + Expr *SubExpr = SubResult.take(); + E->setSubExpr(SubExpr); + E->setType(SubExpr->getType()); + E->setValueKind(SubExpr->getValueKind()); + assert(E->getObjectKind() == OK_Ordinary); + return E; + } + + ExprResult VisitParenExpr(ParenExpr *E) { + return rebuildSugarExpr(E); + } + + ExprResult VisitUnaryExtension(UnaryOperator *E) { + return rebuildSugarExpr(E); + } + + ExprResult VisitUnaryAddrOf(UnaryOperator *E) { + ExprResult SubResult = Visit(E->getSubExpr()); + if (SubResult.isInvalid()) return ExprError(); + + Expr *SubExpr = SubResult.take(); + E->setSubExpr(SubExpr); + E->setType(S.Context.getPointerType(SubExpr->getType())); + assert(E->getValueKind() == VK_RValue); + assert(E->getObjectKind() == OK_Ordinary); + return E; + } + + ExprResult resolveDecl(Expr *E, ValueDecl *VD) { + if (!isa<FunctionDecl>(VD)) return VisitExpr(E); + + E->setType(VD->getType()); + + assert(E->getValueKind() == VK_RValue); + if (S.getLangOpts().CPlusPlus && + !(isa<CXXMethodDecl>(VD) && + cast<CXXMethodDecl>(VD)->isInstance())) + E->setValueKind(VK_LValue); + + return E; + } + + ExprResult VisitMemberExpr(MemberExpr *E) { + return resolveDecl(E, E->getMemberDecl()); + } + + ExprResult VisitDeclRefExpr(DeclRefExpr *E) { + return resolveDecl(E, E->getDecl()); + } + }; +} + +/// Given a function expression of unknown-any type, try to rebuild it +/// to have a function type. +static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *FunctionExpr) { + ExprResult Result = RebuildUnknownAnyFunction(S).Visit(FunctionExpr); + if (Result.isInvalid()) return ExprError(); + return S.DefaultFunctionArrayConversion(Result.take()); +} + +namespace { + /// A visitor for rebuilding an expression of type __unknown_anytype + /// into one which resolves the type directly on the referring + /// expression. Strict preservation of the original source + /// structure is not a goal. + struct RebuildUnknownAnyExpr + : StmtVisitor<RebuildUnknownAnyExpr, ExprResult> { + + Sema &S; + + /// The current destination type. + QualType DestType; + + RebuildUnknownAnyExpr(Sema &S, QualType CastType) + : S(S), DestType(CastType) {} + + ExprResult VisitStmt(Stmt *S) { + llvm_unreachable("unexpected statement!"); + } + + ExprResult VisitExpr(Expr *E) { + S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr) + << E->getSourceRange(); + return ExprError(); + } + + ExprResult VisitCallExpr(CallExpr *E); + ExprResult VisitObjCMessageExpr(ObjCMessageExpr *E); + + /// Rebuild an expression which simply semantically wraps another + /// expression which it shares the type and value kind of. + template <class T> ExprResult rebuildSugarExpr(T *E) { + ExprResult SubResult = Visit(E->getSubExpr()); + if (SubResult.isInvalid()) return ExprError(); + Expr *SubExpr = SubResult.take(); + E->setSubExpr(SubExpr); + E->setType(SubExpr->getType()); + E->setValueKind(SubExpr->getValueKind()); + assert(E->getObjectKind() == OK_Ordinary); + return E; + } + + ExprResult VisitParenExpr(ParenExpr *E) { + return rebuildSugarExpr(E); + } + + ExprResult VisitUnaryExtension(UnaryOperator *E) { + return rebuildSugarExpr(E); + } + + ExprResult VisitUnaryAddrOf(UnaryOperator *E) { + const PointerType *Ptr = DestType->getAs<PointerType>(); + if (!Ptr) { + S.Diag(E->getOperatorLoc(), diag::err_unknown_any_addrof) + << E->getSourceRange(); + return ExprError(); + } + assert(E->getValueKind() == VK_RValue); + assert(E->getObjectKind() == OK_Ordinary); + E->setType(DestType); + + // Build the sub-expression as if it were an object of the pointee type. + DestType = Ptr->getPointeeType(); + ExprResult SubResult = Visit(E->getSubExpr()); + if (SubResult.isInvalid()) return ExprError(); + E->setSubExpr(SubResult.take()); + return E; + } + + ExprResult VisitImplicitCastExpr(ImplicitCastExpr *E); + + ExprResult resolveDecl(Expr *E, ValueDecl *VD); + + ExprResult VisitMemberExpr(MemberExpr *E) { + return resolveDecl(E, E->getMemberDecl()); + } + + ExprResult VisitDeclRefExpr(DeclRefExpr *E) { + return resolveDecl(E, E->getDecl()); + } + }; +} + +/// Rebuilds a call expression which yielded __unknown_anytype. +ExprResult RebuildUnknownAnyExpr::VisitCallExpr(CallExpr *E) { + Expr *CalleeExpr = E->getCallee(); + + enum FnKind { + FK_MemberFunction, + FK_FunctionPointer, + FK_BlockPointer + }; + + FnKind Kind; + QualType CalleeType = CalleeExpr->getType(); + if (CalleeType == S.Context.BoundMemberTy) { + assert(isa<CXXMemberCallExpr>(E) || isa<CXXOperatorCallExpr>(E)); + Kind = FK_MemberFunction; + CalleeType = Expr::findBoundMemberType(CalleeExpr); + } else if (const PointerType *Ptr = CalleeType->getAs<PointerType>()) { + CalleeType = Ptr->getPointeeType(); + Kind = FK_FunctionPointer; + } else { + CalleeType = CalleeType->castAs<BlockPointerType>()->getPointeeType(); + Kind = FK_BlockPointer; + } + const FunctionType *FnType = CalleeType->castAs<FunctionType>(); + + // Verify that this is a legal result type of a function. + if (DestType->isArrayType() || DestType->isFunctionType()) { + unsigned diagID = diag::err_func_returning_array_function; + if (Kind == FK_BlockPointer) + diagID = diag::err_block_returning_array_function; + + S.Diag(E->getExprLoc(), diagID) + << DestType->isFunctionType() << DestType; + return ExprError(); + } + + // Otherwise, go ahead and set DestType as the call's result. + E->setType(DestType.getNonLValueExprType(S.Context)); + E->setValueKind(Expr::getValueKindForType(DestType)); + assert(E->getObjectKind() == OK_Ordinary); + + // Rebuild the function type, replacing the result type with DestType. + if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FnType)) + DestType = S.Context.getFunctionType(DestType, + Proto->arg_type_begin(), + Proto->getNumArgs(), + Proto->getExtProtoInfo()); + else + DestType = S.Context.getFunctionNoProtoType(DestType, + FnType->getExtInfo()); + + // Rebuild the appropriate pointer-to-function type. + switch (Kind) { + case FK_MemberFunction: + // Nothing to do. + break; + + case FK_FunctionPointer: + DestType = S.Context.getPointerType(DestType); + break; + + case FK_BlockPointer: + DestType = S.Context.getBlockPointerType(DestType); + break; + } + + // Finally, we can recurse. + ExprResult CalleeResult = Visit(CalleeExpr); + if (!CalleeResult.isUsable()) return ExprError(); + E->setCallee(CalleeResult.take()); + + // Bind a temporary if necessary. + return S.MaybeBindToTemporary(E); +} + +ExprResult RebuildUnknownAnyExpr::VisitObjCMessageExpr(ObjCMessageExpr *E) { + // Verify that this is a legal result type of a call. + if (DestType->isArrayType() || DestType->isFunctionType()) { + S.Diag(E->getExprLoc(), diag::err_func_returning_array_function) + << DestType->isFunctionType() << DestType; + return ExprError(); + } + + // Rewrite the method result type if available. + if (ObjCMethodDecl *Method = E->getMethodDecl()) { + assert(Method->getResultType() == S.Context.UnknownAnyTy); + Method->setResultType(DestType); + } + + // Change the type of the message. + E->setType(DestType.getNonReferenceType()); + E->setValueKind(Expr::getValueKindForType(DestType)); + + return S.MaybeBindToTemporary(E); +} + +ExprResult RebuildUnknownAnyExpr::VisitImplicitCastExpr(ImplicitCastExpr *E) { + // The only case we should ever see here is a function-to-pointer decay. + if (E->getCastKind() == CK_FunctionToPointerDecay) { + assert(E->getValueKind() == VK_RValue); + assert(E->getObjectKind() == OK_Ordinary); + + E->setType(DestType); + + // Rebuild the sub-expression as the pointee (function) type. + DestType = DestType->castAs<PointerType>()->getPointeeType(); + + ExprResult Result = Visit(E->getSubExpr()); + if (!Result.isUsable()) return ExprError(); + + E->setSubExpr(Result.take()); + return S.Owned(E); + } else if (E->getCastKind() == CK_LValueToRValue) { + assert(E->getValueKind() == VK_RValue); + assert(E->getObjectKind() == OK_Ordinary); + + assert(isa<BlockPointerType>(E->getType())); + + E->setType(DestType); + + // The sub-expression has to be a lvalue reference, so rebuild it as such. + DestType = S.Context.getLValueReferenceType(DestType); + + ExprResult Result = Visit(E->getSubExpr()); + if (!Result.isUsable()) return ExprError(); + + E->setSubExpr(Result.take()); + return S.Owned(E); + } else { + llvm_unreachable("Unhandled cast type!"); + } +} + +ExprResult RebuildUnknownAnyExpr::resolveDecl(Expr *E, ValueDecl *VD) { + ExprValueKind ValueKind = VK_LValue; + QualType Type = DestType; + + // We know how to make this work for certain kinds of decls: + + // - functions + if (FunctionDecl *FD = dyn_cast<FunctionDecl>(VD)) { + if (const PointerType *Ptr = Type->getAs<PointerType>()) { + DestType = Ptr->getPointeeType(); + ExprResult Result = resolveDecl(E, VD); + if (Result.isInvalid()) return ExprError(); + return S.ImpCastExprToType(Result.take(), Type, + CK_FunctionToPointerDecay, VK_RValue); + } + + if (!Type->isFunctionType()) { + S.Diag(E->getExprLoc(), diag::err_unknown_any_function) + << VD << E->getSourceRange(); + return ExprError(); + } + + if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) + if (MD->isInstance()) { + ValueKind = VK_RValue; + Type = S.Context.BoundMemberTy; + } + + // Function references aren't l-values in C. + if (!S.getLangOpts().CPlusPlus) + ValueKind = VK_RValue; + + // - variables + } else if (isa<VarDecl>(VD)) { + if (const ReferenceType *RefTy = Type->getAs<ReferenceType>()) { + Type = RefTy->getPointeeType(); + } else if (Type->isFunctionType()) { + S.Diag(E->getExprLoc(), diag::err_unknown_any_var_function_type) + << VD << E->getSourceRange(); + return ExprError(); + } + + // - nothing else + } else { + S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_decl) + << VD << E->getSourceRange(); + return ExprError(); + } + + VD->setType(DestType); + E->setType(Type); + E->setValueKind(ValueKind); + return S.Owned(E); +} + +/// Check a cast of an unknown-any type. We intentionally only +/// trigger this for C-style casts. +ExprResult Sema::checkUnknownAnyCast(SourceRange TypeRange, QualType CastType, + Expr *CastExpr, CastKind &CastKind, + ExprValueKind &VK, CXXCastPath &Path) { + // Rewrite the casted expression from scratch. + ExprResult result = RebuildUnknownAnyExpr(*this, CastType).Visit(CastExpr); + if (!result.isUsable()) return ExprError(); + + CastExpr = result.take(); + VK = CastExpr->getValueKind(); + CastKind = CK_NoOp; + + return CastExpr; +} + +ExprResult Sema::forceUnknownAnyToType(Expr *E, QualType ToType) { + return RebuildUnknownAnyExpr(*this, ToType).Visit(E); +} + +static ExprResult diagnoseUnknownAnyExpr(Sema &S, Expr *E) { + Expr *orig = E; + unsigned diagID = diag::err_uncasted_use_of_unknown_any; + while (true) { + E = E->IgnoreParenImpCasts(); + if (CallExpr *call = dyn_cast<CallExpr>(E)) { + E = call->getCallee(); + diagID = diag::err_uncasted_call_of_unknown_any; + } else { + break; + } + } + + SourceLocation loc; + NamedDecl *d; + if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(E)) { + loc = ref->getLocation(); + d = ref->getDecl(); + } else if (MemberExpr *mem = dyn_cast<MemberExpr>(E)) { + loc = mem->getMemberLoc(); + d = mem->getMemberDecl(); + } else if (ObjCMessageExpr *msg = dyn_cast<ObjCMessageExpr>(E)) { + diagID = diag::err_uncasted_call_of_unknown_any; + loc = msg->getSelectorStartLoc(); + d = msg->getMethodDecl(); + if (!d) { + S.Diag(loc, diag::err_uncasted_send_to_unknown_any_method) + << static_cast<unsigned>(msg->isClassMessage()) << msg->getSelector() + << orig->getSourceRange(); + return ExprError(); + } + } else { + S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr) + << E->getSourceRange(); + return ExprError(); + } + + S.Diag(loc, diagID) << d << orig->getSourceRange(); + + // Never recoverable. + return ExprError(); +} + +/// Check for operands with placeholder types and complain if found. +/// Returns true if there was an error and no recovery was possible. +ExprResult Sema::CheckPlaceholderExpr(Expr *E) { + const BuiltinType *placeholderType = E->getType()->getAsPlaceholderType(); + if (!placeholderType) return Owned(E); + + switch (placeholderType->getKind()) { + + // Overloaded expressions. + case BuiltinType::Overload: { + // Try to resolve a single function template specialization. + // This is obligatory. + ExprResult result = Owned(E); + if (ResolveAndFixSingleFunctionTemplateSpecialization(result, false)) { + return result; + + // If that failed, try to recover with a call. + } else { + tryToRecoverWithCall(result, PDiag(diag::err_ovl_unresolvable), + /*complain*/ true); + return result; + } + } + + // Bound member functions. + case BuiltinType::BoundMember: { + ExprResult result = Owned(E); + tryToRecoverWithCall(result, PDiag(diag::err_bound_member_function), + /*complain*/ true); + return result; + } + + // ARC unbridged casts. + case BuiltinType::ARCUnbridgedCast: { + Expr *realCast = stripARCUnbridgedCast(E); + diagnoseARCUnbridgedCast(realCast); + return Owned(realCast); + } + + // Expressions of unknown type. + case BuiltinType::UnknownAny: + return diagnoseUnknownAnyExpr(*this, E); + + // Pseudo-objects. + case BuiltinType::PseudoObject: + return checkPseudoObjectRValue(E); + + // Everything else should be impossible. +#define BUILTIN_TYPE(Id, SingletonId) \ + case BuiltinType::Id: +#define PLACEHOLDER_TYPE(Id, SingletonId) +#include "clang/AST/BuiltinTypes.def" + break; + } + + llvm_unreachable("invalid placeholder type!"); +} + +bool Sema::CheckCaseExpression(Expr *E) { + if (E->isTypeDependent()) + return true; + if (E->isValueDependent() || E->isIntegerConstantExpr(Context)) + return E->getType()->isIntegralOrEnumerationType(); + return false; +} + +/// ActOnObjCBoolLiteral - Parse {__objc_yes,__objc_no} literals. +ExprResult +Sema::ActOnObjCBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) { + assert((Kind == tok::kw___objc_yes || Kind == tok::kw___objc_no) && + "Unknown Objective-C Boolean value!"); + QualType ObjCBoolLiteralQT = Context.ObjCBuiltinBoolTy; + // signed char is the default type for boolean literals. Use 'BOOL' + // instead, if BOOL typedef is visible in its scope instead. + Decl *TD = + LookupSingleName(TUScope, &Context.Idents.get("BOOL"), + SourceLocation(), LookupOrdinaryName); + if (TypedefDecl *BoolTD = dyn_cast_or_null<TypedefDecl>(TD)) { + QualType QT = BoolTD->getUnderlyingType(); + if (!QT->isIntegralOrUnscopedEnumerationType()) { + Diag(OpLoc, diag::warn_bool_for_boolean_literal) << QT; + Diag(BoolTD->getLocation(), diag::note_previous_declaration); + } + else + ObjCBoolLiteralQT = QT; + } + + return Owned(new (Context) ObjCBoolLiteralExpr(Kind == tok::kw___objc_yes, + ObjCBoolLiteralQT, OpLoc)); +} |
