From 222e2a7620e6520ffaf4fc4e69d79c18da31542e Mon Sep 17 00:00:00 2001 From: "Zancanaro; Carlo" Date: Mon, 24 Sep 2012 09:58:17 +1000 Subject: Add the clang library to the repo (with some of my changes, too). --- clang/lib/Sema/SemaInit.cpp | 6167 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 6167 insertions(+) create mode 100644 clang/lib/Sema/SemaInit.cpp (limited to 'clang/lib/Sema/SemaInit.cpp') diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp new file mode 100644 index 0000000..a65b41f --- /dev/null +++ b/clang/lib/Sema/SemaInit.cpp @@ -0,0 +1,6167 @@ +//===--- SemaInit.cpp - Semantic Analysis for Initializers ----------------===// +// +// 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 initializers. +// +//===----------------------------------------------------------------------===// + +#include "clang/Sema/Designator.h" +#include "clang/Sema/Initialization.h" +#include "clang/Sema/Lookup.h" +#include "clang/Sema/SemaInternal.h" +#include "clang/Lex/Preprocessor.h" +#include "clang/AST/ASTContext.h" +#include "clang/AST/DeclObjC.h" +#include "clang/AST/ExprCXX.h" +#include "clang/AST/ExprObjC.h" +#include "clang/AST/TypeLoc.h" +#include "llvm/ADT/APInt.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/raw_ostream.h" +#include +using namespace clang; + +//===----------------------------------------------------------------------===// +// Sema Initialization Checking +//===----------------------------------------------------------------------===// + +static Expr *IsStringInit(Expr *Init, const ArrayType *AT, + ASTContext &Context) { + if (!isa(AT) && !isa(AT)) + return 0; + + // See if this is a string literal or @encode. + Init = Init->IgnoreParens(); + + // Handle @encode, which is a narrow string. + if (isa(Init) && AT->getElementType()->isCharType()) + return Init; + + // Otherwise we can only handle string literals. + StringLiteral *SL = dyn_cast(Init); + if (SL == 0) return 0; + + QualType ElemTy = Context.getCanonicalType(AT->getElementType()); + + switch (SL->getKind()) { + case StringLiteral::Ascii: + case StringLiteral::UTF8: + // char array can be initialized with a narrow string. + // Only allow char x[] = "foo"; not char x[] = L"foo"; + return ElemTy->isCharType() ? Init : 0; + case StringLiteral::UTF16: + return ElemTy->isChar16Type() ? Init : 0; + case StringLiteral::UTF32: + return ElemTy->isChar32Type() ? Init : 0; + case StringLiteral::Wide: + // wchar_t array can be initialized with a wide string: C99 6.7.8p15 (with + // correction from DR343): "An array with element type compatible with a + // qualified or unqualified version of wchar_t may be initialized by a wide + // string literal, optionally enclosed in braces." + if (Context.typesAreCompatible(Context.getWCharType(), + ElemTy.getUnqualifiedType())) + return Init; + + return 0; + } + + llvm_unreachable("missed a StringLiteral kind?"); +} + +static Expr *IsStringInit(Expr *init, QualType declType, ASTContext &Context) { + const ArrayType *arrayType = Context.getAsArrayType(declType); + if (!arrayType) return 0; + + return IsStringInit(init, arrayType, Context); +} + +static void CheckStringInit(Expr *Str, QualType &DeclT, const ArrayType *AT, + Sema &S) { + // Get the length of the string as parsed. + uint64_t StrLength = + cast(Str->getType())->getSize().getZExtValue(); + + + if (const IncompleteArrayType *IAT = dyn_cast(AT)) { + // C99 6.7.8p14. We have an array of character type with unknown size + // being initialized to a string literal. + llvm::APSInt ConstVal(32); + ConstVal = StrLength; + // Return a new array type (C99 6.7.8p22). + DeclT = S.Context.getConstantArrayType(IAT->getElementType(), + ConstVal, + ArrayType::Normal, 0); + return; + } + + const ConstantArrayType *CAT = cast(AT); + + // We have an array of character type with known size. However, + // the size may be smaller or larger than the string we are initializing. + // FIXME: Avoid truncation for 64-bit length strings. + if (S.getLangOpts().CPlusPlus) { + if (StringLiteral *SL = dyn_cast(Str)) { + // For Pascal strings it's OK to strip off the terminating null character, + // so the example below is valid: + // + // unsigned char a[2] = "\pa"; + if (SL->isPascal()) + StrLength--; + } + + // [dcl.init.string]p2 + if (StrLength > CAT->getSize().getZExtValue()) + S.Diag(Str->getLocStart(), + diag::err_initializer_string_for_char_array_too_long) + << Str->getSourceRange(); + } else { + // C99 6.7.8p14. + if (StrLength-1 > CAT->getSize().getZExtValue()) + S.Diag(Str->getLocStart(), + diag::warn_initializer_string_for_char_array_too_long) + << Str->getSourceRange(); + } + + // Set the type to the actual size that we are initializing. If we have + // something like: + // char x[1] = "foo"; + // then this will set the string literal's type to char[1]. + Str->setType(DeclT); +} + +//===----------------------------------------------------------------------===// +// Semantic checking for initializer lists. +//===----------------------------------------------------------------------===// + +/// @brief Semantic checking for initializer lists. +/// +/// The InitListChecker class contains a set of routines that each +/// handle the initialization of a certain kind of entity, e.g., +/// arrays, vectors, struct/union types, scalars, etc. The +/// InitListChecker itself performs a recursive walk of the subobject +/// structure of the type to be initialized, while stepping through +/// the initializer list one element at a time. The IList and Index +/// parameters to each of the Check* routines contain the active +/// (syntactic) initializer list and the index into that initializer +/// list that represents the current initializer. Each routine is +/// responsible for moving that Index forward as it consumes elements. +/// +/// Each Check* routine also has a StructuredList/StructuredIndex +/// arguments, which contains the current "structured" (semantic) +/// initializer list and the index into that initializer list where we +/// are copying initializers as we map them over to the semantic +/// list. Once we have completed our recursive walk of the subobject +/// structure, we will have constructed a full semantic initializer +/// list. +/// +/// C99 designators cause changes in the initializer list traversal, +/// because they make the initialization "jump" into a specific +/// subobject and then continue the initialization from that +/// point. CheckDesignatedInitializer() recursively steps into the +/// designated subobject and manages backing out the recursion to +/// initialize the subobjects after the one designated. +namespace { +class InitListChecker { + Sema &SemaRef; + bool hadError; + bool VerifyOnly; // no diagnostics, no structure building + bool AllowBraceElision; + llvm::DenseMap SyntacticToSemantic; + InitListExpr *FullyStructuredList; + + void CheckImplicitInitList(const InitializedEntity &Entity, + InitListExpr *ParentIList, QualType T, + unsigned &Index, InitListExpr *StructuredList, + unsigned &StructuredIndex); + void CheckExplicitInitList(const InitializedEntity &Entity, + InitListExpr *IList, QualType &T, + unsigned &Index, InitListExpr *StructuredList, + unsigned &StructuredIndex, + bool TopLevelObject = false); + void CheckListElementTypes(const InitializedEntity &Entity, + InitListExpr *IList, QualType &DeclType, + bool SubobjectIsDesignatorContext, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex, + bool TopLevelObject = false); + void CheckSubElementType(const InitializedEntity &Entity, + InitListExpr *IList, QualType ElemType, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex); + void CheckComplexType(const InitializedEntity &Entity, + InitListExpr *IList, QualType DeclType, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex); + void CheckScalarType(const InitializedEntity &Entity, + InitListExpr *IList, QualType DeclType, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex); + void CheckReferenceType(const InitializedEntity &Entity, + InitListExpr *IList, QualType DeclType, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex); + void CheckVectorType(const InitializedEntity &Entity, + InitListExpr *IList, QualType DeclType, unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex); + void CheckStructUnionTypes(const InitializedEntity &Entity, + InitListExpr *IList, QualType DeclType, + RecordDecl::field_iterator Field, + bool SubobjectIsDesignatorContext, unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex, + bool TopLevelObject = false); + void CheckArrayType(const InitializedEntity &Entity, + InitListExpr *IList, QualType &DeclType, + llvm::APSInt elementIndex, + bool SubobjectIsDesignatorContext, unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex); + bool CheckDesignatedInitializer(const InitializedEntity &Entity, + InitListExpr *IList, DesignatedInitExpr *DIE, + unsigned DesigIdx, + QualType &CurrentObjectType, + RecordDecl::field_iterator *NextField, + llvm::APSInt *NextElementIndex, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex, + bool FinishSubobjectInit, + bool TopLevelObject); + InitListExpr *getStructuredSubobjectInit(InitListExpr *IList, unsigned Index, + QualType CurrentObjectType, + InitListExpr *StructuredList, + unsigned StructuredIndex, + SourceRange InitRange); + void UpdateStructuredListElement(InitListExpr *StructuredList, + unsigned &StructuredIndex, + Expr *expr); + int numArrayElements(QualType DeclType); + int numStructUnionElements(QualType DeclType); + + void FillInValueInitForField(unsigned Init, FieldDecl *Field, + const InitializedEntity &ParentEntity, + InitListExpr *ILE, bool &RequiresSecondPass); + void FillInValueInitializations(const InitializedEntity &Entity, + InitListExpr *ILE, bool &RequiresSecondPass); + bool CheckFlexibleArrayInit(const InitializedEntity &Entity, + Expr *InitExpr, FieldDecl *Field, + bool TopLevelObject); + void CheckValueInitializable(const InitializedEntity &Entity); + +public: + InitListChecker(Sema &S, const InitializedEntity &Entity, + InitListExpr *IL, QualType &T, bool VerifyOnly, + bool AllowBraceElision); + bool HadError() { return hadError; } + + // @brief Retrieves the fully-structured initializer list used for + // semantic analysis and code generation. + InitListExpr *getFullyStructuredList() const { return FullyStructuredList; } +}; +} // end anonymous namespace + +void InitListChecker::CheckValueInitializable(const InitializedEntity &Entity) { + assert(VerifyOnly && + "CheckValueInitializable is only inteded for verification mode."); + + SourceLocation Loc; + InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc, + true); + InitializationSequence InitSeq(SemaRef, Entity, Kind, 0, 0); + if (InitSeq.Failed()) + hadError = true; +} + +void InitListChecker::FillInValueInitForField(unsigned Init, FieldDecl *Field, + const InitializedEntity &ParentEntity, + InitListExpr *ILE, + bool &RequiresSecondPass) { + SourceLocation Loc = ILE->getLocStart(); + unsigned NumInits = ILE->getNumInits(); + InitializedEntity MemberEntity + = InitializedEntity::InitializeMember(Field, &ParentEntity); + if (Init >= NumInits || !ILE->getInit(Init)) { + // FIXME: We probably don't need to handle references + // specially here, since value-initialization of references is + // handled in InitializationSequence. + if (Field->getType()->isReferenceType()) { + // C++ [dcl.init.aggr]p9: + // If an incomplete or empty initializer-list leaves a + // member of reference type uninitialized, the program is + // ill-formed. + SemaRef.Diag(Loc, diag::err_init_reference_member_uninitialized) + << Field->getType() + << ILE->getSyntacticForm()->getSourceRange(); + SemaRef.Diag(Field->getLocation(), + diag::note_uninit_reference_member); + hadError = true; + return; + } + + InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc, + true); + InitializationSequence InitSeq(SemaRef, MemberEntity, Kind, 0, 0); + if (!InitSeq) { + InitSeq.Diagnose(SemaRef, MemberEntity, Kind, 0, 0); + hadError = true; + return; + } + + ExprResult MemberInit + = InitSeq.Perform(SemaRef, MemberEntity, Kind, MultiExprArg()); + if (MemberInit.isInvalid()) { + hadError = true; + return; + } + + if (hadError) { + // Do nothing + } else if (Init < NumInits) { + ILE->setInit(Init, MemberInit.takeAs()); + } else if (InitSeq.isConstructorInitialization()) { + // Value-initialization requires a constructor call, so + // extend the initializer list to include the constructor + // call and make a note that we'll need to take another pass + // through the initializer list. + ILE->updateInit(SemaRef.Context, Init, MemberInit.takeAs()); + RequiresSecondPass = true; + } + } else if (InitListExpr *InnerILE + = dyn_cast(ILE->getInit(Init))) + FillInValueInitializations(MemberEntity, InnerILE, + RequiresSecondPass); +} + +/// Recursively replaces NULL values within the given initializer list +/// with expressions that perform value-initialization of the +/// appropriate type. +void +InitListChecker::FillInValueInitializations(const InitializedEntity &Entity, + InitListExpr *ILE, + bool &RequiresSecondPass) { + assert((ILE->getType() != SemaRef.Context.VoidTy) && + "Should not have void type"); + SourceLocation Loc = ILE->getLocStart(); + if (ILE->getSyntacticForm()) + Loc = ILE->getSyntacticForm()->getLocStart(); + + if (const RecordType *RType = ILE->getType()->getAs()) { + if (RType->getDecl()->isUnion() && + ILE->getInitializedFieldInUnion()) + FillInValueInitForField(0, ILE->getInitializedFieldInUnion(), + Entity, ILE, RequiresSecondPass); + else { + unsigned Init = 0; + for (RecordDecl::field_iterator + Field = RType->getDecl()->field_begin(), + FieldEnd = RType->getDecl()->field_end(); + Field != FieldEnd; ++Field) { + if (Field->isUnnamedBitfield()) + continue; + + if (hadError) + return; + + FillInValueInitForField(Init, *Field, Entity, ILE, RequiresSecondPass); + if (hadError) + return; + + ++Init; + + // Only look at the first initialization of a union. + if (RType->getDecl()->isUnion()) + break; + } + } + + return; + } + + QualType ElementType; + + InitializedEntity ElementEntity = Entity; + unsigned NumInits = ILE->getNumInits(); + unsigned NumElements = NumInits; + if (const ArrayType *AType = SemaRef.Context.getAsArrayType(ILE->getType())) { + ElementType = AType->getElementType(); + if (const ConstantArrayType *CAType = dyn_cast(AType)) + NumElements = CAType->getSize().getZExtValue(); + ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context, + 0, Entity); + } else if (const VectorType *VType = ILE->getType()->getAs()) { + ElementType = VType->getElementType(); + NumElements = VType->getNumElements(); + ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context, + 0, Entity); + } else + ElementType = ILE->getType(); + + + for (unsigned Init = 0; Init != NumElements; ++Init) { + if (hadError) + return; + + if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement || + ElementEntity.getKind() == InitializedEntity::EK_VectorElement) + ElementEntity.setElementIndex(Init); + + Expr *InitExpr = (Init < NumInits ? ILE->getInit(Init) : 0); + if (!InitExpr && !ILE->hasArrayFiller()) { + InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc, + true); + InitializationSequence InitSeq(SemaRef, ElementEntity, Kind, 0, 0); + if (!InitSeq) { + InitSeq.Diagnose(SemaRef, ElementEntity, Kind, 0, 0); + hadError = true; + return; + } + + ExprResult ElementInit + = InitSeq.Perform(SemaRef, ElementEntity, Kind, MultiExprArg()); + if (ElementInit.isInvalid()) { + hadError = true; + return; + } + + if (hadError) { + // Do nothing + } else if (Init < NumInits) { + // For arrays, just set the expression used for value-initialization + // of the "holes" in the array. + if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) + ILE->setArrayFiller(ElementInit.takeAs()); + else + ILE->setInit(Init, ElementInit.takeAs()); + } else { + // For arrays, just set the expression used for value-initialization + // of the rest of elements and exit. + if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) { + ILE->setArrayFiller(ElementInit.takeAs()); + return; + } + + if (InitSeq.isConstructorInitialization()) { + // Value-initialization requires a constructor call, so + // extend the initializer list to include the constructor + // call and make a note that we'll need to take another pass + // through the initializer list. + ILE->updateInit(SemaRef.Context, Init, ElementInit.takeAs()); + RequiresSecondPass = true; + } + } + } else if (InitListExpr *InnerILE + = dyn_cast_or_null(InitExpr)) + FillInValueInitializations(ElementEntity, InnerILE, RequiresSecondPass); + } +} + + +InitListChecker::InitListChecker(Sema &S, const InitializedEntity &Entity, + InitListExpr *IL, QualType &T, + bool VerifyOnly, bool AllowBraceElision) + : SemaRef(S), VerifyOnly(VerifyOnly), AllowBraceElision(AllowBraceElision) { + hadError = false; + + unsigned newIndex = 0; + unsigned newStructuredIndex = 0; + FullyStructuredList + = getStructuredSubobjectInit(IL, newIndex, T, 0, 0, IL->getSourceRange()); + CheckExplicitInitList(Entity, IL, T, newIndex, + FullyStructuredList, newStructuredIndex, + /*TopLevelObject=*/true); + + if (!hadError && !VerifyOnly) { + bool RequiresSecondPass = false; + FillInValueInitializations(Entity, FullyStructuredList, RequiresSecondPass); + if (RequiresSecondPass && !hadError) + FillInValueInitializations(Entity, FullyStructuredList, + RequiresSecondPass); + } +} + +int InitListChecker::numArrayElements(QualType DeclType) { + // FIXME: use a proper constant + int maxElements = 0x7FFFFFFF; + if (const ConstantArrayType *CAT = + SemaRef.Context.getAsConstantArrayType(DeclType)) { + maxElements = static_cast(CAT->getSize().getZExtValue()); + } + return maxElements; +} + +int InitListChecker::numStructUnionElements(QualType DeclType) { + RecordDecl *structDecl = DeclType->getAs()->getDecl(); + int InitializableMembers = 0; + for (RecordDecl::field_iterator + Field = structDecl->field_begin(), + FieldEnd = structDecl->field_end(); + Field != FieldEnd; ++Field) { + if (!Field->isUnnamedBitfield()) + ++InitializableMembers; + } + if (structDecl->isUnion()) + return std::min(InitializableMembers, 1); + return InitializableMembers - structDecl->hasFlexibleArrayMember(); +} + +void InitListChecker::CheckImplicitInitList(const InitializedEntity &Entity, + InitListExpr *ParentIList, + QualType T, unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex) { + int maxElements = 0; + + if (T->isArrayType()) + maxElements = numArrayElements(T); + else if (T->isRecordType()) + maxElements = numStructUnionElements(T); + else if (T->isVectorType()) + maxElements = T->getAs()->getNumElements(); + else + llvm_unreachable("CheckImplicitInitList(): Illegal type"); + + if (maxElements == 0) { + if (!VerifyOnly) + SemaRef.Diag(ParentIList->getInit(Index)->getLocStart(), + diag::err_implicit_empty_initializer); + ++Index; + hadError = true; + return; + } + + // Build a structured initializer list corresponding to this subobject. + InitListExpr *StructuredSubobjectInitList + = getStructuredSubobjectInit(ParentIList, Index, T, StructuredList, + StructuredIndex, + SourceRange(ParentIList->getInit(Index)->getLocStart(), + ParentIList->getSourceRange().getEnd())); + unsigned StructuredSubobjectInitIndex = 0; + + // Check the element types and build the structural subobject. + unsigned StartIndex = Index; + CheckListElementTypes(Entity, ParentIList, T, + /*SubobjectIsDesignatorContext=*/false, Index, + StructuredSubobjectInitList, + StructuredSubobjectInitIndex); + + if (VerifyOnly) { + if (!AllowBraceElision && (T->isArrayType() || T->isRecordType())) + hadError = true; + } else { + StructuredSubobjectInitList->setType(T); + + unsigned EndIndex = (Index == StartIndex? StartIndex : Index - 1); + // Update the structured sub-object initializer so that it's ending + // range corresponds with the end of the last initializer it used. + if (EndIndex < ParentIList->getNumInits()) { + SourceLocation EndLoc + = ParentIList->getInit(EndIndex)->getSourceRange().getEnd(); + StructuredSubobjectInitList->setRBraceLoc(EndLoc); + } + + // Complain about missing braces. + if (T->isArrayType() || T->isRecordType()) { + SemaRef.Diag(StructuredSubobjectInitList->getLocStart(), + AllowBraceElision ? diag::warn_missing_braces : + diag::err_missing_braces) + << StructuredSubobjectInitList->getSourceRange() + << FixItHint::CreateInsertion( + StructuredSubobjectInitList->getLocStart(), "{") + << FixItHint::CreateInsertion( + SemaRef.PP.getLocForEndOfToken( + StructuredSubobjectInitList->getLocEnd()), + "}"); + if (!AllowBraceElision) + hadError = true; + } + } +} + +void InitListChecker::CheckExplicitInitList(const InitializedEntity &Entity, + InitListExpr *IList, QualType &T, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex, + bool TopLevelObject) { + assert(IList->isExplicit() && "Illegal Implicit InitListExpr"); + if (!VerifyOnly) { + SyntacticToSemantic[IList] = StructuredList; + StructuredList->setSyntacticForm(IList); + } + CheckListElementTypes(Entity, IList, T, /*SubobjectIsDesignatorContext=*/true, + Index, StructuredList, StructuredIndex, TopLevelObject); + if (!VerifyOnly) { + QualType ExprTy = T; + if (!ExprTy->isArrayType()) + ExprTy = ExprTy.getNonLValueExprType(SemaRef.Context); + IList->setType(ExprTy); + StructuredList->setType(ExprTy); + } + if (hadError) + return; + + if (Index < IList->getNumInits()) { + // We have leftover initializers + if (VerifyOnly) { + if (SemaRef.getLangOpts().CPlusPlus || + (SemaRef.getLangOpts().OpenCL && + IList->getType()->isVectorType())) { + hadError = true; + } + return; + } + + if (StructuredIndex == 1 && + IsStringInit(StructuredList->getInit(0), T, SemaRef.Context)) { + unsigned DK = diag::warn_excess_initializers_in_char_array_initializer; + if (SemaRef.getLangOpts().CPlusPlus) { + DK = diag::err_excess_initializers_in_char_array_initializer; + hadError = true; + } + // Special-case + SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK) + << IList->getInit(Index)->getSourceRange(); + } else if (!T->isIncompleteType()) { + // Don't complain for incomplete types, since we'll get an error + // elsewhere + QualType CurrentObjectType = StructuredList->getType(); + int initKind = + CurrentObjectType->isArrayType()? 0 : + CurrentObjectType->isVectorType()? 1 : + CurrentObjectType->isScalarType()? 2 : + CurrentObjectType->isUnionType()? 3 : + 4; + + unsigned DK = diag::warn_excess_initializers; + if (SemaRef.getLangOpts().CPlusPlus) { + DK = diag::err_excess_initializers; + hadError = true; + } + if (SemaRef.getLangOpts().OpenCL && initKind == 1) { + DK = diag::err_excess_initializers; + hadError = true; + } + + SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK) + << initKind << IList->getInit(Index)->getSourceRange(); + } + } + + if (!VerifyOnly && T->isScalarType() && IList->getNumInits() == 1 && + !TopLevelObject) + SemaRef.Diag(IList->getLocStart(), diag::warn_braces_around_scalar_init) + << IList->getSourceRange() + << FixItHint::CreateRemoval(IList->getLocStart()) + << FixItHint::CreateRemoval(IList->getLocEnd()); +} + +void InitListChecker::CheckListElementTypes(const InitializedEntity &Entity, + InitListExpr *IList, + QualType &DeclType, + bool SubobjectIsDesignatorContext, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex, + bool TopLevelObject) { + if (DeclType->isAnyComplexType() && SubobjectIsDesignatorContext) { + // Explicitly braced initializer for complex type can be real+imaginary + // parts. + CheckComplexType(Entity, IList, DeclType, Index, + StructuredList, StructuredIndex); + } else if (DeclType->isScalarType()) { + CheckScalarType(Entity, IList, DeclType, Index, + StructuredList, StructuredIndex); + } else if (DeclType->isVectorType()) { + CheckVectorType(Entity, IList, DeclType, Index, + StructuredList, StructuredIndex); + } else if (DeclType->isAggregateType()) { + if (DeclType->isRecordType()) { + RecordDecl *RD = DeclType->getAs()->getDecl(); + CheckStructUnionTypes(Entity, IList, DeclType, RD->field_begin(), + SubobjectIsDesignatorContext, Index, + StructuredList, StructuredIndex, + TopLevelObject); + } else if (DeclType->isArrayType()) { + llvm::APSInt Zero( + SemaRef.Context.getTypeSize(SemaRef.Context.getSizeType()), + false); + CheckArrayType(Entity, IList, DeclType, Zero, + SubobjectIsDesignatorContext, Index, + StructuredList, StructuredIndex); + } else + llvm_unreachable("Aggregate that isn't a structure or array?!"); + } else if (DeclType->isVoidType() || DeclType->isFunctionType()) { + // This type is invalid, issue a diagnostic. + ++Index; + if (!VerifyOnly) + SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type) + << DeclType; + hadError = true; + } else if (DeclType->isRecordType()) { + // C++ [dcl.init]p14: + // [...] If the class is an aggregate (8.5.1), and the initializer + // is a brace-enclosed list, see 8.5.1. + // + // Note: 8.5.1 is handled below; here, we diagnose the case where + // we have an initializer list and a destination type that is not + // an aggregate. + // FIXME: In C++0x, this is yet another form of initialization. + if (!VerifyOnly) + SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list) + << DeclType << IList->getSourceRange(); + hadError = true; + } else if (DeclType->isReferenceType()) { + CheckReferenceType(Entity, IList, DeclType, Index, + StructuredList, StructuredIndex); + } else if (DeclType->isObjCObjectType()) { + if (!VerifyOnly) + SemaRef.Diag(IList->getLocStart(), diag::err_init_objc_class) + << DeclType; + hadError = true; + } else { + if (!VerifyOnly) + SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type) + << DeclType; + hadError = true; + } +} + +void InitListChecker::CheckSubElementType(const InitializedEntity &Entity, + InitListExpr *IList, + QualType ElemType, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex) { + Expr *expr = IList->getInit(Index); + if (InitListExpr *SubInitList = dyn_cast(expr)) { + unsigned newIndex = 0; + unsigned newStructuredIndex = 0; + InitListExpr *newStructuredList + = getStructuredSubobjectInit(IList, Index, ElemType, + StructuredList, StructuredIndex, + SubInitList->getSourceRange()); + CheckExplicitInitList(Entity, SubInitList, ElemType, newIndex, + newStructuredList, newStructuredIndex); + ++StructuredIndex; + ++Index; + return; + } else if (ElemType->isScalarType()) { + return CheckScalarType(Entity, IList, ElemType, Index, + StructuredList, StructuredIndex); + } else if (ElemType->isReferenceType()) { + return CheckReferenceType(Entity, IList, ElemType, Index, + StructuredList, StructuredIndex); + } + + if (const ArrayType *arrayType = SemaRef.Context.getAsArrayType(ElemType)) { + // arrayType can be incomplete if we're initializing a flexible + // array member. There's nothing we can do with the completed + // type here, though. + + if (Expr *Str = IsStringInit(expr, arrayType, SemaRef.Context)) { + if (!VerifyOnly) { + CheckStringInit(Str, ElemType, arrayType, SemaRef); + UpdateStructuredListElement(StructuredList, StructuredIndex, Str); + } + ++Index; + return; + } + + // Fall through for subaggregate initialization. + + } else if (SemaRef.getLangOpts().CPlusPlus) { + // C++ [dcl.init.aggr]p12: + // All implicit type conversions (clause 4) are considered when + // initializing the aggregate member with an initializer from + // an initializer-list. If the initializer can initialize a + // member, the member is initialized. [...] + + // FIXME: Better EqualLoc? + InitializationKind Kind = + InitializationKind::CreateCopy(expr->getLocStart(), SourceLocation()); + InitializationSequence Seq(SemaRef, Entity, Kind, &expr, 1); + + if (Seq) { + if (!VerifyOnly) { + ExprResult Result = + Seq.Perform(SemaRef, Entity, Kind, MultiExprArg(&expr, 1)); + if (Result.isInvalid()) + hadError = true; + + UpdateStructuredListElement(StructuredList, StructuredIndex, + Result.takeAs()); + } + ++Index; + return; + } + + // Fall through for subaggregate initialization + } else { + // C99 6.7.8p13: + // + // The initializer for a structure or union object that has + // automatic storage duration shall be either an initializer + // list as described below, or a single expression that has + // compatible structure or union type. In the latter case, the + // initial value of the object, including unnamed members, is + // that of the expression. + ExprResult ExprRes = SemaRef.Owned(expr); + if ((ElemType->isRecordType() || ElemType->isVectorType()) && + SemaRef.CheckSingleAssignmentConstraints(ElemType, ExprRes, + !VerifyOnly) + == Sema::Compatible) { + if (ExprRes.isInvalid()) + hadError = true; + else { + ExprRes = SemaRef.DefaultFunctionArrayLvalueConversion(ExprRes.take()); + if (ExprRes.isInvalid()) + hadError = true; + } + UpdateStructuredListElement(StructuredList, StructuredIndex, + ExprRes.takeAs()); + ++Index; + return; + } + ExprRes.release(); + // Fall through for subaggregate initialization + } + + // C++ [dcl.init.aggr]p12: + // + // [...] Otherwise, if the member is itself a non-empty + // subaggregate, brace elision is assumed and the initializer is + // considered for the initialization of the first member of + // the subaggregate. + if (!SemaRef.getLangOpts().OpenCL && + (ElemType->isAggregateType() || ElemType->isVectorType())) { + CheckImplicitInitList(Entity, IList, ElemType, Index, StructuredList, + StructuredIndex); + ++StructuredIndex; + } else { + if (!VerifyOnly) { + // We cannot initialize this element, so let + // PerformCopyInitialization produce the appropriate diagnostic. + SemaRef.PerformCopyInitialization(Entity, SourceLocation(), + SemaRef.Owned(expr), + /*TopLevelOfInitList=*/true); + } + hadError = true; + ++Index; + ++StructuredIndex; + } +} + +void InitListChecker::CheckComplexType(const InitializedEntity &Entity, + InitListExpr *IList, QualType DeclType, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex) { + assert(Index == 0 && "Index in explicit init list must be zero"); + + // As an extension, clang supports complex initializers, which initialize + // a complex number component-wise. When an explicit initializer list for + // a complex number contains two two initializers, this extension kicks in: + // it exepcts the initializer list to contain two elements convertible to + // the element type of the complex type. The first element initializes + // the real part, and the second element intitializes the imaginary part. + + if (IList->getNumInits() != 2) + return CheckScalarType(Entity, IList, DeclType, Index, StructuredList, + StructuredIndex); + + // This is an extension in C. (The builtin _Complex type does not exist + // in the C++ standard.) + if (!SemaRef.getLangOpts().CPlusPlus && !VerifyOnly) + SemaRef.Diag(IList->getLocStart(), diag::ext_complex_component_init) + << IList->getSourceRange(); + + // Initialize the complex number. + QualType elementType = DeclType->getAs()->getElementType(); + InitializedEntity ElementEntity = + InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); + + for (unsigned i = 0; i < 2; ++i) { + ElementEntity.setElementIndex(Index); + CheckSubElementType(ElementEntity, IList, elementType, Index, + StructuredList, StructuredIndex); + } +} + + +void InitListChecker::CheckScalarType(const InitializedEntity &Entity, + InitListExpr *IList, QualType DeclType, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex) { + if (Index >= IList->getNumInits()) { + if (!VerifyOnly) + SemaRef.Diag(IList->getLocStart(), + SemaRef.getLangOpts().CPlusPlus0x ? + diag::warn_cxx98_compat_empty_scalar_initializer : + diag::err_empty_scalar_initializer) + << IList->getSourceRange(); + hadError = !SemaRef.getLangOpts().CPlusPlus0x; + ++Index; + ++StructuredIndex; + return; + } + + Expr *expr = IList->getInit(Index); + if (InitListExpr *SubIList = dyn_cast(expr)) { + if (!VerifyOnly) + SemaRef.Diag(SubIList->getLocStart(), + diag::warn_many_braces_around_scalar_init) + << SubIList->getSourceRange(); + + CheckScalarType(Entity, SubIList, DeclType, Index, StructuredList, + StructuredIndex); + return; + } else if (isa(expr)) { + if (!VerifyOnly) + SemaRef.Diag(expr->getLocStart(), + diag::err_designator_for_scalar_init) + << DeclType << expr->getSourceRange(); + hadError = true; + ++Index; + ++StructuredIndex; + return; + } + + if (VerifyOnly) { + if (!SemaRef.CanPerformCopyInitialization(Entity, SemaRef.Owned(expr))) + hadError = true; + ++Index; + return; + } + + ExprResult Result = + SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), + SemaRef.Owned(expr), + /*TopLevelOfInitList=*/true); + + Expr *ResultExpr = 0; + + if (Result.isInvalid()) + hadError = true; // types weren't compatible. + else { + ResultExpr = Result.takeAs(); + + if (ResultExpr != expr) { + // The type was promoted, update initializer list. + IList->setInit(Index, ResultExpr); + } + } + if (hadError) + ++StructuredIndex; + else + UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr); + ++Index; +} + +void InitListChecker::CheckReferenceType(const InitializedEntity &Entity, + InitListExpr *IList, QualType DeclType, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex) { + if (Index >= IList->getNumInits()) { + // FIXME: It would be wonderful if we could point at the actual member. In + // general, it would be useful to pass location information down the stack, + // so that we know the location (or decl) of the "current object" being + // initialized. + if (!VerifyOnly) + SemaRef.Diag(IList->getLocStart(), + diag::err_init_reference_member_uninitialized) + << DeclType + << IList->getSourceRange(); + hadError = true; + ++Index; + ++StructuredIndex; + return; + } + + Expr *expr = IList->getInit(Index); + if (isa(expr) && !SemaRef.getLangOpts().CPlusPlus0x) { + if (!VerifyOnly) + SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list) + << DeclType << IList->getSourceRange(); + hadError = true; + ++Index; + ++StructuredIndex; + return; + } + + if (VerifyOnly) { + if (!SemaRef.CanPerformCopyInitialization(Entity, SemaRef.Owned(expr))) + hadError = true; + ++Index; + return; + } + + ExprResult Result = + SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), + SemaRef.Owned(expr), + /*TopLevelOfInitList=*/true); + + if (Result.isInvalid()) + hadError = true; + + expr = Result.takeAs(); + IList->setInit(Index, expr); + + if (hadError) + ++StructuredIndex; + else + UpdateStructuredListElement(StructuredList, StructuredIndex, expr); + ++Index; +} + +void InitListChecker::CheckVectorType(const InitializedEntity &Entity, + InitListExpr *IList, QualType DeclType, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex) { + const VectorType *VT = DeclType->getAs(); + unsigned maxElements = VT->getNumElements(); + unsigned numEltsInit = 0; + QualType elementType = VT->getElementType(); + + if (Index >= IList->getNumInits()) { + // Make sure the element type can be value-initialized. + if (VerifyOnly) + CheckValueInitializable( + InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity)); + return; + } + + if (!SemaRef.getLangOpts().OpenCL) { + // If the initializing element is a vector, try to copy-initialize + // instead of breaking it apart (which is doomed to failure anyway). + Expr *Init = IList->getInit(Index); + if (!isa(Init) && Init->getType()->isVectorType()) { + if (VerifyOnly) { + if (!SemaRef.CanPerformCopyInitialization(Entity, SemaRef.Owned(Init))) + hadError = true; + ++Index; + return; + } + + ExprResult Result = + SemaRef.PerformCopyInitialization(Entity, Init->getLocStart(), + SemaRef.Owned(Init), + /*TopLevelOfInitList=*/true); + + Expr *ResultExpr = 0; + if (Result.isInvalid()) + hadError = true; // types weren't compatible. + else { + ResultExpr = Result.takeAs(); + + if (ResultExpr != Init) { + // The type was promoted, update initializer list. + IList->setInit(Index, ResultExpr); + } + } + if (hadError) + ++StructuredIndex; + else + UpdateStructuredListElement(StructuredList, StructuredIndex, + ResultExpr); + ++Index; + return; + } + + InitializedEntity ElementEntity = + InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); + + for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) { + // Don't attempt to go past the end of the init list + if (Index >= IList->getNumInits()) { + if (VerifyOnly) + CheckValueInitializable(ElementEntity); + break; + } + + ElementEntity.setElementIndex(Index); + CheckSubElementType(ElementEntity, IList, elementType, Index, + StructuredList, StructuredIndex); + } + return; + } + + InitializedEntity ElementEntity = + InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); + + // OpenCL initializers allows vectors to be constructed from vectors. + for (unsigned i = 0; i < maxElements; ++i) { + // Don't attempt to go past the end of the init list + if (Index >= IList->getNumInits()) + break; + + ElementEntity.setElementIndex(Index); + + QualType IType = IList->getInit(Index)->getType(); + if (!IType->isVectorType()) { + CheckSubElementType(ElementEntity, IList, elementType, Index, + StructuredList, StructuredIndex); + ++numEltsInit; + } else { + QualType VecType; + const VectorType *IVT = IType->getAs(); + unsigned numIElts = IVT->getNumElements(); + + if (IType->isExtVectorType()) + VecType = SemaRef.Context.getExtVectorType(elementType, numIElts); + else + VecType = SemaRef.Context.getVectorType(elementType, numIElts, + IVT->getVectorKind()); + CheckSubElementType(ElementEntity, IList, VecType, Index, + StructuredList, StructuredIndex); + numEltsInit += numIElts; + } + } + + // OpenCL requires all elements to be initialized. + if (numEltsInit != maxElements) { + if (!VerifyOnly) + SemaRef.Diag(IList->getLocStart(), + diag::err_vector_incorrect_num_initializers) + << (numEltsInit < maxElements) << maxElements << numEltsInit; + hadError = true; + } +} + +void InitListChecker::CheckArrayType(const InitializedEntity &Entity, + InitListExpr *IList, QualType &DeclType, + llvm::APSInt elementIndex, + bool SubobjectIsDesignatorContext, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex) { + const ArrayType *arrayType = SemaRef.Context.getAsArrayType(DeclType); + + // Check for the special-case of initializing an array with a string. + if (Index < IList->getNumInits()) { + if (Expr *Str = IsStringInit(IList->getInit(Index), arrayType, + SemaRef.Context)) { + // We place the string literal directly into the resulting + // initializer list. This is the only place where the structure + // of the structured initializer list doesn't match exactly, + // because doing so would involve allocating one character + // constant for each string. + if (!VerifyOnly) { + CheckStringInit(Str, DeclType, arrayType, SemaRef); + UpdateStructuredListElement(StructuredList, StructuredIndex, Str); + StructuredList->resizeInits(SemaRef.Context, StructuredIndex); + } + ++Index; + return; + } + } + if (const VariableArrayType *VAT = dyn_cast(arrayType)) { + // Check for VLAs; in standard C it would be possible to check this + // earlier, but I don't know where clang accepts VLAs (gcc accepts + // them in all sorts of strange places). + if (!VerifyOnly) + SemaRef.Diag(VAT->getSizeExpr()->getLocStart(), + diag::err_variable_object_no_init) + << VAT->getSizeExpr()->getSourceRange(); + hadError = true; + ++Index; + ++StructuredIndex; + return; + } + + // We might know the maximum number of elements in advance. + llvm::APSInt maxElements(elementIndex.getBitWidth(), + elementIndex.isUnsigned()); + bool maxElementsKnown = false; + if (const ConstantArrayType *CAT = dyn_cast(arrayType)) { + maxElements = CAT->getSize(); + elementIndex = elementIndex.extOrTrunc(maxElements.getBitWidth()); + elementIndex.setIsUnsigned(maxElements.isUnsigned()); + maxElementsKnown = true; + } + + QualType elementType = arrayType->getElementType(); + while (Index < IList->getNumInits()) { + Expr *Init = IList->getInit(Index); + if (DesignatedInitExpr *DIE = dyn_cast(Init)) { + // If we're not the subobject that matches up with the '{' for + // the designator, we shouldn't be handling the + // designator. Return immediately. + if (!SubobjectIsDesignatorContext) + return; + + // Handle this designated initializer. elementIndex will be + // updated to be the next array element we'll initialize. + if (CheckDesignatedInitializer(Entity, IList, DIE, 0, + DeclType, 0, &elementIndex, Index, + StructuredList, StructuredIndex, true, + false)) { + hadError = true; + continue; + } + + if (elementIndex.getBitWidth() > maxElements.getBitWidth()) + maxElements = maxElements.extend(elementIndex.getBitWidth()); + else if (elementIndex.getBitWidth() < maxElements.getBitWidth()) + elementIndex = elementIndex.extend(maxElements.getBitWidth()); + elementIndex.setIsUnsigned(maxElements.isUnsigned()); + + // If the array is of incomplete type, keep track of the number of + // elements in the initializer. + if (!maxElementsKnown && elementIndex > maxElements) + maxElements = elementIndex; + + continue; + } + + // If we know the maximum number of elements, and we've already + // hit it, stop consuming elements in the initializer list. + if (maxElementsKnown && elementIndex == maxElements) + break; + + InitializedEntity ElementEntity = + InitializedEntity::InitializeElement(SemaRef.Context, StructuredIndex, + Entity); + // Check this element. + CheckSubElementType(ElementEntity, IList, elementType, Index, + StructuredList, StructuredIndex); + ++elementIndex; + + // If the array is of incomplete type, keep track of the number of + // elements in the initializer. + if (!maxElementsKnown && elementIndex > maxElements) + maxElements = elementIndex; + } + if (!hadError && DeclType->isIncompleteArrayType() && !VerifyOnly) { + // If this is an incomplete array type, the actual type needs to + // be calculated here. + llvm::APSInt Zero(maxElements.getBitWidth(), maxElements.isUnsigned()); + if (maxElements == Zero) { + // Sizing an array implicitly to zero is not allowed by ISO C, + // but is supported by GNU. + SemaRef.Diag(IList->getLocStart(), + diag::ext_typecheck_zero_array_size); + } + + DeclType = SemaRef.Context.getConstantArrayType(elementType, maxElements, + ArrayType::Normal, 0); + } + if (!hadError && VerifyOnly) { + // Check if there are any members of the array that get value-initialized. + // If so, check if doing that is possible. + // FIXME: This needs to detect holes left by designated initializers too. + if (maxElementsKnown && elementIndex < maxElements) + CheckValueInitializable(InitializedEntity::InitializeElement( + SemaRef.Context, 0, Entity)); + } +} + +bool InitListChecker::CheckFlexibleArrayInit(const InitializedEntity &Entity, + Expr *InitExpr, + FieldDecl *Field, + bool TopLevelObject) { + // Handle GNU flexible array initializers. + unsigned FlexArrayDiag; + if (isa(InitExpr) && + cast(InitExpr)->getNumInits() == 0) { + // Empty flexible array init always allowed as an extension + FlexArrayDiag = diag::ext_flexible_array_init; + } else if (SemaRef.getLangOpts().CPlusPlus) { + // Disallow flexible array init in C++; it is not required for gcc + // compatibility, and it needs work to IRGen correctly in general. + FlexArrayDiag = diag::err_flexible_array_init; + } else if (!TopLevelObject) { + // Disallow flexible array init on non-top-level object + FlexArrayDiag = diag::err_flexible_array_init; + } else if (Entity.getKind() != InitializedEntity::EK_Variable) { + // Disallow flexible array init on anything which is not a variable. + FlexArrayDiag = diag::err_flexible_array_init; + } else if (cast(Entity.getDecl())->hasLocalStorage()) { + // Disallow flexible array init on local variables. + FlexArrayDiag = diag::err_flexible_array_init; + } else { + // Allow other cases. + FlexArrayDiag = diag::ext_flexible_array_init; + } + + if (!VerifyOnly) { + SemaRef.Diag(InitExpr->getLocStart(), + FlexArrayDiag) + << InitExpr->getLocStart(); + SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) + << Field; + } + + return FlexArrayDiag != diag::ext_flexible_array_init; +} + +void InitListChecker::CheckStructUnionTypes(const InitializedEntity &Entity, + InitListExpr *IList, + QualType DeclType, + RecordDecl::field_iterator Field, + bool SubobjectIsDesignatorContext, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex, + bool TopLevelObject) { + RecordDecl* structDecl = DeclType->getAs()->getDecl(); + + // If the record is invalid, some of it's members are invalid. To avoid + // confusion, we forgo checking the intializer for the entire record. + if (structDecl->isInvalidDecl()) { + hadError = true; + return; + } + + if (DeclType->isUnionType() && IList->getNumInits() == 0) { + // Value-initialize the first named member of the union. + RecordDecl *RD = DeclType->getAs()->getDecl(); + for (RecordDecl::field_iterator FieldEnd = RD->field_end(); + Field != FieldEnd; ++Field) { + if (Field->getDeclName()) { + if (VerifyOnly) + CheckValueInitializable( + InitializedEntity::InitializeMember(*Field, &Entity)); + else + StructuredList->setInitializedFieldInUnion(*Field); + break; + } + } + return; + } + + // If structDecl is a forward declaration, this loop won't do + // anything except look at designated initializers; That's okay, + // because an error should get printed out elsewhere. It might be + // worthwhile to skip over the rest of the initializer, though. + RecordDecl *RD = DeclType->getAs()->getDecl(); + RecordDecl::field_iterator FieldEnd = RD->field_end(); + bool InitializedSomething = false; + bool CheckForMissingFields = true; + while (Index < IList->getNumInits()) { + Expr *Init = IList->getInit(Index); + + if (DesignatedInitExpr *DIE = dyn_cast(Init)) { + // If we're not the subobject that matches up with the '{' for + // the designator, we shouldn't be handling the + // designator. Return immediately. + if (!SubobjectIsDesignatorContext) + return; + + // Handle this designated initializer. Field will be updated to + // the next field that we'll be initializing. + if (CheckDesignatedInitializer(Entity, IList, DIE, 0, + DeclType, &Field, 0, Index, + StructuredList, StructuredIndex, + true, TopLevelObject)) + hadError = true; + + InitializedSomething = true; + + // Disable check for missing fields when designators are used. + // This matches gcc behaviour. + CheckForMissingFields = false; + continue; + } + + if (Field == FieldEnd) { + // We've run out of fields. We're done. + break; + } + + // We've already initialized a member of a union. We're done. + if (InitializedSomething && DeclType->isUnionType()) + break; + + // If we've hit the flexible array member at the end, we're done. + if (Field->getType()->isIncompleteArrayType()) + break; + + if (Field->isUnnamedBitfield()) { + // Don't initialize unnamed bitfields, e.g. "int : 20;" + ++Field; + continue; + } + + // Make sure we can use this declaration. + bool InvalidUse; + if (VerifyOnly) + InvalidUse = !SemaRef.CanUseDecl(*Field); + else + InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, + IList->getInit(Index)->getLocStart()); + if (InvalidUse) { + ++Index; + ++Field; + hadError = true; + continue; + } + + InitializedEntity MemberEntity = + InitializedEntity::InitializeMember(*Field, &Entity); + CheckSubElementType(MemberEntity, IList, Field->getType(), Index, + StructuredList, StructuredIndex); + InitializedSomething = true; + + if (DeclType->isUnionType() && !VerifyOnly) { + // Initialize the first field within the union. + StructuredList->setInitializedFieldInUnion(*Field); + } + + ++Field; + } + + // Emit warnings for missing struct field initializers. + if (!VerifyOnly && InitializedSomething && CheckForMissingFields && + Field != FieldEnd && !Field->getType()->isIncompleteArrayType() && + !DeclType->isUnionType()) { + // It is possible we have one or more unnamed bitfields remaining. + // Find first (if any) named field and emit warning. + for (RecordDecl::field_iterator it = Field, end = RD->field_end(); + it != end; ++it) { + if (!it->isUnnamedBitfield()) { + SemaRef.Diag(IList->getSourceRange().getEnd(), + diag::warn_missing_field_initializers) << it->getName(); + break; + } + } + } + + // Check that any remaining fields can be value-initialized. + if (VerifyOnly && Field != FieldEnd && !DeclType->isUnionType() && + !Field->getType()->isIncompleteArrayType()) { + // FIXME: Should check for holes left by designated initializers too. + for (; Field != FieldEnd && !hadError; ++Field) { + if (!Field->isUnnamedBitfield()) + CheckValueInitializable( + InitializedEntity::InitializeMember(*Field, &Entity)); + } + } + + if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() || + Index >= IList->getNumInits()) + return; + + if (CheckFlexibleArrayInit(Entity, IList->getInit(Index), *Field, + TopLevelObject)) { + hadError = true; + ++Index; + return; + } + + InitializedEntity MemberEntity = + InitializedEntity::InitializeMember(*Field, &Entity); + + if (isa(IList->getInit(Index))) + CheckSubElementType(MemberEntity, IList, Field->getType(), Index, + StructuredList, StructuredIndex); + else + CheckImplicitInitList(MemberEntity, IList, Field->getType(), Index, + StructuredList, StructuredIndex); +} + +/// \brief Expand a field designator that refers to a member of an +/// anonymous struct or union into a series of field designators that +/// refers to the field within the appropriate subobject. +/// +static void ExpandAnonymousFieldDesignator(Sema &SemaRef, + DesignatedInitExpr *DIE, + unsigned DesigIdx, + IndirectFieldDecl *IndirectField) { + typedef DesignatedInitExpr::Designator Designator; + + // Build the replacement designators. + SmallVector Replacements; + for (IndirectFieldDecl::chain_iterator PI = IndirectField->chain_begin(), + PE = IndirectField->chain_end(); PI != PE; ++PI) { + if (PI + 1 == PE) + Replacements.push_back(Designator((IdentifierInfo *)0, + DIE->getDesignator(DesigIdx)->getDotLoc(), + DIE->getDesignator(DesigIdx)->getFieldLoc())); + else + Replacements.push_back(Designator((IdentifierInfo *)0, SourceLocation(), + SourceLocation())); + assert(isa(*PI)); + Replacements.back().setField(cast(*PI)); + } + + // Expand the current designator into the set of replacement + // designators, so we have a full subobject path down to where the + // member of the anonymous struct/union is actually stored. + DIE->ExpandDesignator(SemaRef.Context, DesigIdx, &Replacements[0], + &Replacements[0] + Replacements.size()); +} + +/// \brief Given an implicit anonymous field, search the IndirectField that +/// corresponds to FieldName. +static IndirectFieldDecl *FindIndirectFieldDesignator(FieldDecl *AnonField, + IdentifierInfo *FieldName) { + assert(AnonField->isAnonymousStructOrUnion()); + Decl *NextDecl = AnonField->getNextDeclInContext(); + while (IndirectFieldDecl *IF = + dyn_cast_or_null(NextDecl)) { + if (FieldName && FieldName == IF->getAnonField()->getIdentifier()) + return IF; + NextDecl = NextDecl->getNextDeclInContext(); + } + return 0; +} + +static DesignatedInitExpr *CloneDesignatedInitExpr(Sema &SemaRef, + DesignatedInitExpr *DIE) { + unsigned NumIndexExprs = DIE->getNumSubExprs() - 1; + SmallVector IndexExprs(NumIndexExprs); + for (unsigned I = 0; I < NumIndexExprs; ++I) + IndexExprs[I] = DIE->getSubExpr(I + 1); + return DesignatedInitExpr::Create(SemaRef.Context, DIE->designators_begin(), + DIE->size(), IndexExprs.data(), + NumIndexExprs, DIE->getEqualOrColonLoc(), + DIE->usesGNUSyntax(), DIE->getInit()); +} + +namespace { + +// Callback to only accept typo corrections that are for field members of +// the given struct or union. +class FieldInitializerValidatorCCC : public CorrectionCandidateCallback { + public: + explicit FieldInitializerValidatorCCC(RecordDecl *RD) + : Record(RD) {} + + virtual bool ValidateCandidate(const TypoCorrection &candidate) { + FieldDecl *FD = candidate.getCorrectionDeclAs(); + return FD && FD->getDeclContext()->getRedeclContext()->Equals(Record); + } + + private: + RecordDecl *Record; +}; + +} + +/// @brief Check the well-formedness of a C99 designated initializer. +/// +/// Determines whether the designated initializer @p DIE, which +/// resides at the given @p Index within the initializer list @p +/// IList, is well-formed for a current object of type @p DeclType +/// (C99 6.7.8). The actual subobject that this designator refers to +/// within the current subobject is returned in either +/// @p NextField or @p NextElementIndex (whichever is appropriate). +/// +/// @param IList The initializer list in which this designated +/// initializer occurs. +/// +/// @param DIE The designated initializer expression. +/// +/// @param DesigIdx The index of the current designator. +/// +/// @param DeclType The type of the "current object" (C99 6.7.8p17), +/// into which the designation in @p DIE should refer. +/// +/// @param NextField If non-NULL and the first designator in @p DIE is +/// a field, this will be set to the field declaration corresponding +/// to the field named by the designator. +/// +/// @param NextElementIndex If non-NULL and the first designator in @p +/// DIE is an array designator or GNU array-range designator, this +/// will be set to the last index initialized by this designator. +/// +/// @param Index Index into @p IList where the designated initializer +/// @p DIE occurs. +/// +/// @param StructuredList The initializer list expression that +/// describes all of the subobject initializers in the order they'll +/// actually be initialized. +/// +/// @returns true if there was an error, false otherwise. +bool +InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity, + InitListExpr *IList, + DesignatedInitExpr *DIE, + unsigned DesigIdx, + QualType &CurrentObjectType, + RecordDecl::field_iterator *NextField, + llvm::APSInt *NextElementIndex, + unsigned &Index, + InitListExpr *StructuredList, + unsigned &StructuredIndex, + bool FinishSubobjectInit, + bool TopLevelObject) { + if (DesigIdx == DIE->size()) { + // Check the actual initialization for the designated object type. + bool prevHadError = hadError; + + // Temporarily remove the designator expression from the + // initializer list that the child calls see, so that we don't try + // to re-process the designator. + unsigned OldIndex = Index; + IList->setInit(OldIndex, DIE->getInit()); + + CheckSubElementType(Entity, IList, CurrentObjectType, Index, + StructuredList, StructuredIndex); + + // Restore the designated initializer expression in the syntactic + // form of the initializer list. + if (IList->getInit(OldIndex) != DIE->getInit()) + DIE->setInit(IList->getInit(OldIndex)); + IList->setInit(OldIndex, DIE); + + return hadError && !prevHadError; + } + + DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx); + bool IsFirstDesignator = (DesigIdx == 0); + if (!VerifyOnly) { + assert((IsFirstDesignator || StructuredList) && + "Need a non-designated initializer list to start from"); + + // Determine the structural initializer list that corresponds to the + // current subobject. + StructuredList = IsFirstDesignator? SyntacticToSemantic.lookup(IList) + : getStructuredSubobjectInit(IList, Index, CurrentObjectType, + StructuredList, StructuredIndex, + SourceRange(D->getStartLocation(), + DIE->getSourceRange().getEnd())); + assert(StructuredList && "Expected a structured initializer list"); + } + + if (D->isFieldDesignator()) { + // C99 6.7.8p7: + // + // If a designator has the form + // + // . identifier + // + // then the current object (defined below) shall have + // structure or union type and the identifier shall be the + // name of a member of that type. + const RecordType *RT = CurrentObjectType->getAs(); + if (!RT) { + SourceLocation Loc = D->getDotLoc(); + if (Loc.isInvalid()) + Loc = D->getFieldLoc(); + if (!VerifyOnly) + SemaRef.Diag(Loc, diag::err_field_designator_non_aggr) + << SemaRef.getLangOpts().CPlusPlus << CurrentObjectType; + ++Index; + return true; + } + + // Note: we perform a linear search of the fields here, despite + // the fact that we have a faster lookup method, because we always + // need to compute the field's index. + FieldDecl *KnownField = D->getField(); + IdentifierInfo *FieldName = D->getFieldName(); + unsigned FieldIndex = 0; + RecordDecl::field_iterator + Field = RT->getDecl()->field_begin(), + FieldEnd = RT->getDecl()->field_end(); + for (; Field != FieldEnd; ++Field) { + if (Field->isUnnamedBitfield()) + continue; + + // If we find a field representing an anonymous field, look in the + // IndirectFieldDecl that follow for the designated initializer. + if (!KnownField && Field->isAnonymousStructOrUnion()) { + if (IndirectFieldDecl *IF = + FindIndirectFieldDesignator(*Field, FieldName)) { + // In verify mode, don't modify the original. + if (VerifyOnly) + DIE = CloneDesignatedInitExpr(SemaRef, DIE); + ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, IF); + D = DIE->getDesignator(DesigIdx); + break; + } + } + if (KnownField && KnownField == *Field) + break; + if (FieldName && FieldName == Field->getIdentifier()) + break; + + ++FieldIndex; + } + + if (Field == FieldEnd) { + if (VerifyOnly) { + ++Index; + return true; // No typo correction when just trying this out. + } + + // There was no normal field in the struct with the designated + // name. Perform another lookup for this name, which may find + // something that we can't designate (e.g., a member function), + // may find nothing, or may find a member of an anonymous + // struct/union. + DeclContext::lookup_result Lookup = RT->getDecl()->lookup(FieldName); + FieldDecl *ReplacementField = 0; + if (Lookup.first == Lookup.second) { + // Name lookup didn't find anything. Determine whether this + // was a typo for another field name. + FieldInitializerValidatorCCC Validator(RT->getDecl()); + TypoCorrection Corrected = SemaRef.CorrectTypo( + DeclarationNameInfo(FieldName, D->getFieldLoc()), + Sema::LookupMemberName, /*Scope=*/0, /*SS=*/0, Validator, + RT->getDecl()); + if (Corrected) { + std::string CorrectedStr( + Corrected.getAsString(SemaRef.getLangOpts())); + std::string CorrectedQuotedStr( + Corrected.getQuoted(SemaRef.getLangOpts())); + ReplacementField = Corrected.getCorrectionDeclAs(); + SemaRef.Diag(D->getFieldLoc(), + diag::err_field_designator_unknown_suggest) + << FieldName << CurrentObjectType << CorrectedQuotedStr + << FixItHint::CreateReplacement(D->getFieldLoc(), CorrectedStr); + SemaRef.Diag(ReplacementField->getLocation(), + diag::note_previous_decl) << CorrectedQuotedStr; + hadError = true; + } else { + SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown) + << FieldName << CurrentObjectType; + ++Index; + return true; + } + } + + if (!ReplacementField) { + // Name lookup found something, but it wasn't a field. + SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_nonfield) + << FieldName; + SemaRef.Diag((*Lookup.first)->getLocation(), + diag::note_field_designator_found); + ++Index; + return true; + } + + if (!KnownField) { + // The replacement field comes from typo correction; find it + // in the list of fields. + FieldIndex = 0; + Field = RT->getDecl()->field_begin(); + for (; Field != FieldEnd; ++Field) { + if (Field->isUnnamedBitfield()) + continue; + + if (ReplacementField == *Field || + Field->getIdentifier() == ReplacementField->getIdentifier()) + break; + + ++FieldIndex; + } + } + } + + // All of the fields of a union are located at the same place in + // the initializer list. + if (RT->getDecl()->isUnion()) { + FieldIndex = 0; + if (!VerifyOnly) + StructuredList->setInitializedFieldInUnion(*Field); + } + + // Make sure we can use this declaration. + bool InvalidUse; + if (VerifyOnly) + InvalidUse = !SemaRef.CanUseDecl(*Field); + else + InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, D->getFieldLoc()); + if (InvalidUse) { + ++Index; + return true; + } + + if (!VerifyOnly) { + // Update the designator with the field declaration. + D->setField(*Field); + + // Make sure that our non-designated initializer list has space + // for a subobject corresponding to this field. + if (FieldIndex >= StructuredList->getNumInits()) + StructuredList->resizeInits(SemaRef.Context, FieldIndex + 1); + } + + // This designator names a flexible array member. + if (Field->getType()->isIncompleteArrayType()) { + bool Invalid = false; + if ((DesigIdx + 1) != DIE->size()) { + // We can't designate an object within the flexible array + // member (because GCC doesn't allow it). + if (!VerifyOnly) { + DesignatedInitExpr::Designator *NextD + = DIE->getDesignator(DesigIdx + 1); + SemaRef.Diag(NextD->getStartLocation(), + diag::err_designator_into_flexible_array_member) + << SourceRange(NextD->getStartLocation(), + DIE->getSourceRange().getEnd()); + SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) + << *Field; + } + Invalid = true; + } + + if (!hadError && !isa(DIE->getInit()) && + !isa(DIE->getInit())) { + // The initializer is not an initializer list. + if (!VerifyOnly) { + SemaRef.Diag(DIE->getInit()->getLocStart(), + diag::err_flexible_array_init_needs_braces) + << DIE->getInit()->getSourceRange(); + SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) + << *Field; + } + Invalid = true; + } + + // Check GNU flexible array initializer. + if (!Invalid && CheckFlexibleArrayInit(Entity, DIE->getInit(), *Field, + TopLevelObject)) + Invalid = true; + + if (Invalid) { + ++Index; + return true; + } + + // Initialize the array. + bool prevHadError = hadError; + unsigned newStructuredIndex = FieldIndex; + unsigned OldIndex = Index; + IList->setInit(Index, DIE->getInit()); + + InitializedEntity MemberEntity = + InitializedEntity::InitializeMember(*Field, &Entity); + CheckSubElementType(MemberEntity, IList, Field->getType(), Index, + StructuredList, newStructuredIndex); + + IList->setInit(OldIndex, DIE); + if (hadError && !prevHadError) { + ++Field; + ++FieldIndex; + if (NextField) + *NextField = Field; + StructuredIndex = FieldIndex; + return true; + } + } else { + // Recurse to check later designated subobjects. + QualType FieldType = (*Field)->getType(); + unsigned newStructuredIndex = FieldIndex; + + InitializedEntity MemberEntity = + InitializedEntity::InitializeMember(*Field, &Entity); + if (CheckDesignatedInitializer(MemberEntity, IList, DIE, DesigIdx + 1, + FieldType, 0, 0, Index, + StructuredList, newStructuredIndex, + true, false)) + return true; + } + + // Find the position of the next field to be initialized in this + // subobject. + ++Field; + ++FieldIndex; + + // If this the first designator, our caller will continue checking + // the rest of this struct/class/union subobject. + if (IsFirstDesignator) { + if (NextField) + *NextField = Field; + StructuredIndex = FieldIndex; + return false; + } + + if (!FinishSubobjectInit) + return false; + + // We've already initialized something in the union; we're done. + if (RT->getDecl()->isUnion()) + return hadError; + + // Check the remaining fields within this class/struct/union subobject. + bool prevHadError = hadError; + + CheckStructUnionTypes(Entity, IList, CurrentObjectType, Field, false, Index, + StructuredList, FieldIndex); + return hadError && !prevHadError; + } + + // C99 6.7.8p6: + // + // If a designator has the form + // + // [ constant-expression ] + // + // then the current object (defined below) shall have array + // type and the expression shall be an integer constant + // expression. If the array is of unknown size, any + // nonnegative value is valid. + // + // Additionally, cope with the GNU extension that permits + // designators of the form + // + // [ constant-expression ... constant-expression ] + const ArrayType *AT = SemaRef.Context.getAsArrayType(CurrentObjectType); + if (!AT) { + if (!VerifyOnly) + SemaRef.Diag(D->getLBracketLoc(), diag::err_array_designator_non_array) + << CurrentObjectType; + ++Index; + return true; + } + + Expr *IndexExpr = 0; + llvm::APSInt DesignatedStartIndex, DesignatedEndIndex; + if (D->isArrayDesignator()) { + IndexExpr = DIE->getArrayIndex(*D); + DesignatedStartIndex = IndexExpr->EvaluateKnownConstInt(SemaRef.Context); + DesignatedEndIndex = DesignatedStartIndex; + } else { + assert(D->isArrayRangeDesignator() && "Need array-range designator"); + + DesignatedStartIndex = + DIE->getArrayRangeStart(*D)->EvaluateKnownConstInt(SemaRef.Context); + DesignatedEndIndex = + DIE->getArrayRangeEnd(*D)->EvaluateKnownConstInt(SemaRef.Context); + IndexExpr = DIE->getArrayRangeEnd(*D); + + // Codegen can't handle evaluating array range designators that have side + // effects, because we replicate the AST value for each initialized element. + // As such, set the sawArrayRangeDesignator() bit if we initialize multiple + // elements with something that has a side effect, so codegen can emit an + // "error unsupported" error instead of miscompiling the app. + if (DesignatedStartIndex.getZExtValue()!=DesignatedEndIndex.getZExtValue()&& + DIE->getInit()->HasSideEffects(SemaRef.Context) && !VerifyOnly) + FullyStructuredList->sawArrayRangeDesignator(); + } + + if (isa(AT)) { + llvm::APSInt MaxElements(cast(AT)->getSize(), false); + DesignatedStartIndex + = DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth()); + DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned()); + DesignatedEndIndex + = DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth()); + DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned()); + if (DesignatedEndIndex >= MaxElements) { + if (!VerifyOnly) + SemaRef.Diag(IndexExpr->getLocStart(), + diag::err_array_designator_too_large) + << DesignatedEndIndex.toString(10) << MaxElements.toString(10) + << IndexExpr->getSourceRange(); + ++Index; + return true; + } + } else { + // Make sure the bit-widths and signedness match. + if (DesignatedStartIndex.getBitWidth() > DesignatedEndIndex.getBitWidth()) + DesignatedEndIndex + = DesignatedEndIndex.extend(DesignatedStartIndex.getBitWidth()); + else if (DesignatedStartIndex.getBitWidth() < + DesignatedEndIndex.getBitWidth()) + DesignatedStartIndex + = DesignatedStartIndex.extend(DesignatedEndIndex.getBitWidth()); + DesignatedStartIndex.setIsUnsigned(true); + DesignatedEndIndex.setIsUnsigned(true); + } + + // Make sure that our non-designated initializer list has space + // for a subobject corresponding to this array element. + if (!VerifyOnly && + DesignatedEndIndex.getZExtValue() >= StructuredList->getNumInits()) + StructuredList->resizeInits(SemaRef.Context, + DesignatedEndIndex.getZExtValue() + 1); + + // Repeatedly perform subobject initializations in the range + // [DesignatedStartIndex, DesignatedEndIndex]. + + // Move to the next designator + unsigned ElementIndex = DesignatedStartIndex.getZExtValue(); + unsigned OldIndex = Index; + + InitializedEntity ElementEntity = + InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); + + while (DesignatedStartIndex <= DesignatedEndIndex) { + // Recurse to check later designated subobjects. + QualType ElementType = AT->getElementType(); + Index = OldIndex; + + ElementEntity.setElementIndex(ElementIndex); + if (CheckDesignatedInitializer(ElementEntity, IList, DIE, DesigIdx + 1, + ElementType, 0, 0, Index, + StructuredList, ElementIndex, + (DesignatedStartIndex == DesignatedEndIndex), + false)) + return true; + + // Move to the next index in the array that we'll be initializing. + ++DesignatedStartIndex; + ElementIndex = DesignatedStartIndex.getZExtValue(); + } + + // If this the first designator, our caller will continue checking + // the rest of this array subobject. + if (IsFirstDesignator) { + if (NextElementIndex) + *NextElementIndex = DesignatedStartIndex; + StructuredIndex = ElementIndex; + return false; + } + + if (!FinishSubobjectInit) + return false; + + // Check the remaining elements within this array subobject. + bool prevHadError = hadError; + CheckArrayType(Entity, IList, CurrentObjectType, DesignatedStartIndex, + /*SubobjectIsDesignatorContext=*/false, Index, + StructuredList, ElementIndex); + return hadError && !prevHadError; +} + +// Get the structured initializer list for a subobject of type +// @p CurrentObjectType. +InitListExpr * +InitListChecker::getStructuredSubobjectInit(InitListExpr *IList, unsigned Index, + QualType CurrentObjectType, + InitListExpr *StructuredList, + unsigned StructuredIndex, + SourceRange InitRange) { + if (VerifyOnly) + return 0; // No structured list in verification-only mode. + Expr *ExistingInit = 0; + if (!StructuredList) + ExistingInit = SyntacticToSemantic.lookup(IList); + else if (StructuredIndex < StructuredList->getNumInits()) + ExistingInit = StructuredList->getInit(StructuredIndex); + + if (InitListExpr *Result = dyn_cast_or_null(ExistingInit)) + return Result; + + if (ExistingInit) { + // We are creating an initializer list that initializes the + // subobjects of the current object, but there was already an + // initialization that completely initialized the current + // subobject, e.g., by a compound literal: + // + // struct X { int a, b; }; + // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 }; + // + // Here, xs[0].a == 0 and xs[0].b == 3, since the second, + // designated initializer re-initializes the whole + // subobject [0], overwriting previous initializers. + SemaRef.Diag(InitRange.getBegin(), + diag::warn_subobject_initializer_overrides) + << InitRange; + SemaRef.Diag(ExistingInit->getLocStart(), + diag::note_previous_initializer) + << /*FIXME:has side effects=*/0 + << ExistingInit->getSourceRange(); + } + + InitListExpr *Result + = new (SemaRef.Context) InitListExpr(SemaRef.Context, + InitRange.getBegin(), 0, 0, + InitRange.getEnd()); + + QualType ResultType = CurrentObjectType; + if (!ResultType->isArrayType()) + ResultType = ResultType.getNonLValueExprType(SemaRef.Context); + Result->setType(ResultType); + + // Pre-allocate storage for the structured initializer list. + unsigned NumElements = 0; + unsigned NumInits = 0; + bool GotNumInits = false; + if (!StructuredList) { + NumInits = IList->getNumInits(); + GotNumInits = true; + } else if (Index < IList->getNumInits()) { + if (InitListExpr *SubList = dyn_cast(IList->getInit(Index))) { + NumInits = SubList->getNumInits(); + GotNumInits = true; + } + } + + if (const ArrayType *AType + = SemaRef.Context.getAsArrayType(CurrentObjectType)) { + if (const ConstantArrayType *CAType = dyn_cast(AType)) { + NumElements = CAType->getSize().getZExtValue(); + // Simple heuristic so that we don't allocate a very large + // initializer with many empty entries at the end. + if (GotNumInits && NumElements > NumInits) + NumElements = 0; + } + } else if (const VectorType *VType = CurrentObjectType->getAs()) + NumElements = VType->getNumElements(); + else if (const RecordType *RType = CurrentObjectType->getAs()) { + RecordDecl *RDecl = RType->getDecl(); + if (RDecl->isUnion()) + NumElements = 1; + else + NumElements = std::distance(RDecl->field_begin(), + RDecl->field_end()); + } + + Result->reserveInits(SemaRef.Context, NumElements); + + // Link this new initializer list into the structured initializer + // lists. + if (StructuredList) + StructuredList->updateInit(SemaRef.Context, StructuredIndex, Result); + else { + Result->setSyntacticForm(IList); + SyntacticToSemantic[IList] = Result; + } + + return Result; +} + +/// Update the initializer at index @p StructuredIndex within the +/// structured initializer list to the value @p expr. +void InitListChecker::UpdateStructuredListElement(InitListExpr *StructuredList, + unsigned &StructuredIndex, + Expr *expr) { + // No structured initializer list to update + if (!StructuredList) + return; + + if (Expr *PrevInit = StructuredList->updateInit(SemaRef.Context, + StructuredIndex, expr)) { + // This initializer overwrites a previous initializer. Warn. + SemaRef.Diag(expr->getLocStart(), + diag::warn_initializer_overrides) + << expr->getSourceRange(); + SemaRef.Diag(PrevInit->getLocStart(), + diag::note_previous_initializer) + << /*FIXME:has side effects=*/0 + << PrevInit->getSourceRange(); + } + + ++StructuredIndex; +} + +/// Check that the given Index expression is a valid array designator +/// value. This is essentially just a wrapper around +/// VerifyIntegerConstantExpression that also checks for negative values +/// and produces a reasonable diagnostic if there is a +/// failure. Returns the index expression, possibly with an implicit cast +/// added, on success. If everything went okay, Value will receive the +/// value of the constant expression. +static ExprResult +CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) { + SourceLocation Loc = Index->getLocStart(); + + // Make sure this is an integer constant expression. + ExprResult Result = S.VerifyIntegerConstantExpression(Index, &Value); + if (Result.isInvalid()) + return Result; + + if (Value.isSigned() && Value.isNegative()) + return S.Diag(Loc, diag::err_array_designator_negative) + << Value.toString(10) << Index->getSourceRange(); + + Value.setIsUnsigned(true); + return Result; +} + +ExprResult Sema::ActOnDesignatedInitializer(Designation &Desig, + SourceLocation Loc, + bool GNUSyntax, + ExprResult Init) { + typedef DesignatedInitExpr::Designator ASTDesignator; + + bool Invalid = false; + SmallVector Designators; + SmallVector InitExpressions; + + // Build designators and check array designator expressions. + for (unsigned Idx = 0; Idx < Desig.getNumDesignators(); ++Idx) { + const Designator &D = Desig.getDesignator(Idx); + switch (D.getKind()) { + case Designator::FieldDesignator: + Designators.push_back(ASTDesignator(D.getField(), D.getDotLoc(), + D.getFieldLoc())); + break; + + case Designator::ArrayDesignator: { + Expr *Index = static_cast(D.getArrayIndex()); + llvm::APSInt IndexValue; + if (!Index->isTypeDependent() && !Index->isValueDependent()) + Index = CheckArrayDesignatorExpr(*this, Index, IndexValue).take(); + if (!Index) + Invalid = true; + else { + Designators.push_back(ASTDesignator(InitExpressions.size(), + D.getLBracketLoc(), + D.getRBracketLoc())); + InitExpressions.push_back(Index); + } + break; + } + + case Designator::ArrayRangeDesignator: { + Expr *StartIndex = static_cast(D.getArrayRangeStart()); + Expr *EndIndex = static_cast(D.getArrayRangeEnd()); + llvm::APSInt StartValue; + llvm::APSInt EndValue; + bool StartDependent = StartIndex->isTypeDependent() || + StartIndex->isValueDependent(); + bool EndDependent = EndIndex->isTypeDependent() || + EndIndex->isValueDependent(); + if (!StartDependent) + StartIndex = + CheckArrayDesignatorExpr(*this, StartIndex, StartValue).take(); + if (!EndDependent) + EndIndex = CheckArrayDesignatorExpr(*this, EndIndex, EndValue).take(); + + if (!StartIndex || !EndIndex) + Invalid = true; + else { + // Make sure we're comparing values with the same bit width. + if (StartDependent || EndDependent) { + // Nothing to compute. + } else if (StartValue.getBitWidth() > EndValue.getBitWidth()) + EndValue = EndValue.extend(StartValue.getBitWidth()); + else if (StartValue.getBitWidth() < EndValue.getBitWidth()) + StartValue = StartValue.extend(EndValue.getBitWidth()); + + if (!StartDependent && !EndDependent && EndValue < StartValue) { + Diag(D.getEllipsisLoc(), diag::err_array_designator_empty_range) + << StartValue.toString(10) << EndValue.toString(10) + << StartIndex->getSourceRange() << EndIndex->getSourceRange(); + Invalid = true; + } else { + Designators.push_back(ASTDesignator(InitExpressions.size(), + D.getLBracketLoc(), + D.getEllipsisLoc(), + D.getRBracketLoc())); + InitExpressions.push_back(StartIndex); + InitExpressions.push_back(EndIndex); + } + } + break; + } + } + } + + if (Invalid || Init.isInvalid()) + return ExprError(); + + // Clear out the expressions within the designation. + Desig.ClearExprs(*this); + + DesignatedInitExpr *DIE + = DesignatedInitExpr::Create(Context, + Designators.data(), Designators.size(), + InitExpressions.data(), InitExpressions.size(), + Loc, GNUSyntax, Init.takeAs()); + + if (!getLangOpts().C99) + Diag(DIE->getLocStart(), diag::ext_designated_init) + << DIE->getSourceRange(); + + return Owned(DIE); +} + +//===----------------------------------------------------------------------===// +// Initialization entity +//===----------------------------------------------------------------------===// + +InitializedEntity::InitializedEntity(ASTContext &Context, unsigned Index, + const InitializedEntity &Parent) + : Parent(&Parent), Index(Index) +{ + if (const ArrayType *AT = Context.getAsArrayType(Parent.getType())) { + Kind = EK_ArrayElement; + Type = AT->getElementType(); + } else if (const VectorType *VT = Parent.getType()->getAs()) { + Kind = EK_VectorElement; + Type = VT->getElementType(); + } else { + const ComplexType *CT = Parent.getType()->getAs(); + assert(CT && "Unexpected type"); + Kind = EK_ComplexElement; + Type = CT->getElementType(); + } +} + +InitializedEntity InitializedEntity::InitializeBase(ASTContext &Context, + CXXBaseSpecifier *Base, + bool IsInheritedVirtualBase) +{ + InitializedEntity Result; + Result.Kind = EK_Base; + Result.Base = reinterpret_cast(Base); + if (IsInheritedVirtualBase) + Result.Base |= 0x01; + + Result.Type = Base->getType(); + return Result; +} + +DeclarationName InitializedEntity::getName() const { + switch (getKind()) { + case EK_Parameter: { + ParmVarDecl *D = reinterpret_cast(Parameter & ~0x1); + return (D ? D->getDeclName() : DeclarationName()); + } + + case EK_Variable: + case EK_Member: + return VariableOrMember->getDeclName(); + + case EK_LambdaCapture: + return Capture.Var->getDeclName(); + + case EK_Result: + case EK_Exception: + case EK_New: + case EK_Temporary: + case EK_Base: + case EK_Delegating: + case EK_ArrayElement: + case EK_VectorElement: + case EK_ComplexElement: + case EK_BlockElement: + return DeclarationName(); + } + + llvm_unreachable("Invalid EntityKind!"); +} + +DeclaratorDecl *InitializedEntity::getDecl() const { + switch (getKind()) { + case EK_Variable: + case EK_Member: + return VariableOrMember; + + case EK_Parameter: + return reinterpret_cast(Parameter & ~0x1); + + case EK_Result: + case EK_Exception: + case EK_New: + case EK_Temporary: + case EK_Base: + case EK_Delegating: + case EK_ArrayElement: + case EK_VectorElement: + case EK_ComplexElement: + case EK_BlockElement: + case EK_LambdaCapture: + return 0; + } + + llvm_unreachable("Invalid EntityKind!"); +} + +bool InitializedEntity::allowsNRVO() const { + switch (getKind()) { + case EK_Result: + case EK_Exception: + return LocAndNRVO.NRVO; + + case EK_Variable: + case EK_Parameter: + case EK_Member: + case EK_New: + case EK_Temporary: + case EK_Base: + case EK_Delegating: + case EK_ArrayElement: + case EK_VectorElement: + case EK_ComplexElement: + case EK_BlockElement: + case EK_LambdaCapture: + break; + } + + return false; +} + +//===----------------------------------------------------------------------===// +// Initialization sequence +//===----------------------------------------------------------------------===// + +void InitializationSequence::Step::Destroy() { + switch (Kind) { + case SK_ResolveAddressOfOverloadedFunction: + case SK_CastDerivedToBaseRValue: + case SK_CastDerivedToBaseXValue: + case SK_CastDerivedToBaseLValue: + case SK_BindReference: + case SK_BindReferenceToTemporary: + case SK_ExtraneousCopyToTemporary: + case SK_UserConversion: + case SK_QualificationConversionRValue: + case SK_QualificationConversionXValue: + case SK_QualificationConversionLValue: + case SK_ListInitialization: + case SK_ListConstructorCall: + case SK_UnwrapInitList: + case SK_RewrapInitList: + case SK_ConstructorInitialization: + case SK_ZeroInitialization: + case SK_CAssignment: + case SK_StringInit: + case SK_ObjCObjectConversion: + case SK_ArrayInit: + case SK_ParenthesizedArrayInit: + case SK_PassByIndirectCopyRestore: + case SK_PassByIndirectRestore: + case SK_ProduceObjCObject: + case SK_StdInitializerList: + break; + + case SK_ConversionSequence: + delete ICS; + } +} + +bool InitializationSequence::isDirectReferenceBinding() const { + return !Steps.empty() && Steps.back().Kind == SK_BindReference; +} + +bool InitializationSequence::isAmbiguous() const { + if (!Failed()) + return false; + + switch (getFailureKind()) { + case FK_TooManyInitsForReference: + case FK_ArrayNeedsInitList: + case FK_ArrayNeedsInitListOrStringLiteral: + case FK_AddressOfOverloadFailed: // FIXME: Could do better + case FK_NonConstLValueReferenceBindingToTemporary: + case FK_NonConstLValueReferenceBindingToUnrelated: + case FK_RValueReferenceBindingToLValue: + case FK_ReferenceInitDropsQualifiers: + case FK_ReferenceInitFailed: + case FK_ConversionFailed: + case FK_ConversionFromPropertyFailed: + case FK_TooManyInitsForScalar: + case FK_ReferenceBindingToInitList: + case FK_InitListBadDestinationType: + case FK_DefaultInitOfConst: + case FK_Incomplete: + case FK_ArrayTypeMismatch: + case FK_NonConstantArrayInit: + case FK_ListInitializationFailed: + case FK_VariableLengthArrayHasInitializer: + case FK_PlaceholderType: + case FK_InitListElementCopyFailure: + case FK_ExplicitConstructor: + return false; + + case FK_ReferenceInitOverloadFailed: + case FK_UserConversionOverloadFailed: + case FK_ConstructorOverloadFailed: + case FK_ListConstructorOverloadFailed: + return FailedOverloadResult == OR_Ambiguous; + } + + llvm_unreachable("Invalid EntityKind!"); +} + +bool InitializationSequence::isConstructorInitialization() const { + return !Steps.empty() && Steps.back().Kind == SK_ConstructorInitialization; +} + +void +InitializationSequence +::AddAddressOverloadResolutionStep(FunctionDecl *Function, + DeclAccessPair Found, + bool HadMultipleCandidates) { + Step S; + S.Kind = SK_ResolveAddressOfOverloadedFunction; + S.Type = Function->getType(); + S.Function.HadMultipleCandidates = HadMultipleCandidates; + S.Function.Function = Function; + S.Function.FoundDecl = Found; + Steps.push_back(S); +} + +void InitializationSequence::AddDerivedToBaseCastStep(QualType BaseType, + ExprValueKind VK) { + Step S; + switch (VK) { + case VK_RValue: S.Kind = SK_CastDerivedToBaseRValue; break; + case VK_XValue: S.Kind = SK_CastDerivedToBaseXValue; break; + case VK_LValue: S.Kind = SK_CastDerivedToBaseLValue; break; + } + S.Type = BaseType; + Steps.push_back(S); +} + +void InitializationSequence::AddReferenceBindingStep(QualType T, + bool BindingTemporary) { + Step S; + S.Kind = BindingTemporary? SK_BindReferenceToTemporary : SK_BindReference; + S.Type = T; + Steps.push_back(S); +} + +void InitializationSequence::AddExtraneousCopyToTemporary(QualType T) { + Step S; + S.Kind = SK_ExtraneousCopyToTemporary; + S.Type = T; + Steps.push_back(S); +} + +void +InitializationSequence::AddUserConversionStep(FunctionDecl *Function, + DeclAccessPair FoundDecl, + QualType T, + bool HadMultipleCandidates) { + Step S; + S.Kind = SK_UserConversion; + S.Type = T; + S.Function.HadMultipleCandidates = HadMultipleCandidates; + S.Function.Function = Function; + S.Function.FoundDecl = FoundDecl; + Steps.push_back(S); +} + +void InitializationSequence::AddQualificationConversionStep(QualType Ty, + ExprValueKind VK) { + Step S; + S.Kind = SK_QualificationConversionRValue; // work around a gcc warning + switch (VK) { + case VK_RValue: + S.Kind = SK_QualificationConversionRValue; + break; + case VK_XValue: + S.Kind = SK_QualificationConversionXValue; + break; + case VK_LValue: + S.Kind = SK_QualificationConversionLValue; + break; + } + S.Type = Ty; + Steps.push_back(S); +} + +void InitializationSequence::AddConversionSequenceStep( + const ImplicitConversionSequence &ICS, + QualType T) { + Step S; + S.Kind = SK_ConversionSequence; + S.Type = T; + S.ICS = new ImplicitConversionSequence(ICS); + Steps.push_back(S); +} + +void InitializationSequence::AddListInitializationStep(QualType T) { + Step S; + S.Kind = SK_ListInitialization; + S.Type = T; + Steps.push_back(S); +} + +void +InitializationSequence +::AddConstructorInitializationStep(CXXConstructorDecl *Constructor, + AccessSpecifier Access, + QualType T, + bool HadMultipleCandidates, + bool FromInitList, bool AsInitList) { + Step S; + S.Kind = FromInitList && !AsInitList ? SK_ListConstructorCall + : SK_ConstructorInitialization; + S.Type = T; + S.Function.HadMultipleCandidates = HadMultipleCandidates; + S.Function.Function = Constructor; + S.Function.FoundDecl = DeclAccessPair::make(Constructor, Access); + Steps.push_back(S); +} + +void InitializationSequence::AddZeroInitializationStep(QualType T) { + Step S; + S.Kind = SK_ZeroInitialization; + S.Type = T; + Steps.push_back(S); +} + +void InitializationSequence::AddCAssignmentStep(QualType T) { + Step S; + S.Kind = SK_CAssignment; + S.Type = T; + Steps.push_back(S); +} + +void InitializationSequence::AddStringInitStep(QualType T) { + Step S; + S.Kind = SK_StringInit; + S.Type = T; + Steps.push_back(S); +} + +void InitializationSequence::AddObjCObjectConversionStep(QualType T) { + Step S; + S.Kind = SK_ObjCObjectConversion; + S.Type = T; + Steps.push_back(S); +} + +void InitializationSequence::AddArrayInitStep(QualType T) { + Step S; + S.Kind = SK_ArrayInit; + S.Type = T; + Steps.push_back(S); +} + +void InitializationSequence::AddParenthesizedArrayInitStep(QualType T) { + Step S; + S.Kind = SK_ParenthesizedArrayInit; + S.Type = T; + Steps.push_back(S); +} + +void InitializationSequence::AddPassByIndirectCopyRestoreStep(QualType type, + bool shouldCopy) { + Step s; + s.Kind = (shouldCopy ? SK_PassByIndirectCopyRestore + : SK_PassByIndirectRestore); + s.Type = type; + Steps.push_back(s); +} + +void InitializationSequence::AddProduceObjCObjectStep(QualType T) { + Step S; + S.Kind = SK_ProduceObjCObject; + S.Type = T; + Steps.push_back(S); +} + +void InitializationSequence::AddStdInitializerListConstructionStep(QualType T) { + Step S; + S.Kind = SK_StdInitializerList; + S.Type = T; + Steps.push_back(S); +} + +void InitializationSequence::RewrapReferenceInitList(QualType T, + InitListExpr *Syntactic) { + assert(Syntactic->getNumInits() == 1 && + "Can only rewrap trivial init lists."); + Step S; + S.Kind = SK_UnwrapInitList; + S.Type = Syntactic->getInit(0)->getType(); + Steps.insert(Steps.begin(), S); + + S.Kind = SK_RewrapInitList; + S.Type = T; + S.WrappingSyntacticList = Syntactic; + Steps.push_back(S); +} + +void InitializationSequence::SetOverloadFailure(FailureKind Failure, + OverloadingResult Result) { + setSequenceKind(FailedSequence); + this->Failure = Failure; + this->FailedOverloadResult = Result; +} + +//===----------------------------------------------------------------------===// +// Attempt initialization +//===----------------------------------------------------------------------===// + +static void MaybeProduceObjCObject(Sema &S, + InitializationSequence &Sequence, + const InitializedEntity &Entity) { + if (!S.getLangOpts().ObjCAutoRefCount) return; + + /// When initializing a parameter, produce the value if it's marked + /// __attribute__((ns_consumed)). + if (Entity.getKind() == InitializedEntity::EK_Parameter) { + if (!Entity.isParameterConsumed()) + return; + + assert(Entity.getType()->isObjCRetainableType() && + "consuming an object of unretainable type?"); + Sequence.AddProduceObjCObjectStep(Entity.getType()); + + /// When initializing a return value, if the return type is a + /// retainable type, then returns need to immediately retain the + /// object. If an autorelease is required, it will be done at the + /// last instant. + } else if (Entity.getKind() == InitializedEntity::EK_Result) { + if (!Entity.getType()->isObjCRetainableType()) + return; + + Sequence.AddProduceObjCObjectStep(Entity.getType()); + } +} + +/// \brief When initializing from init list via constructor, deal with the +/// empty init list and std::initializer_list special cases. +/// +/// \return True if this was a special case, false otherwise. +static bool TryListConstructionSpecialCases(Sema &S, + InitListExpr *List, + CXXRecordDecl *DestRecordDecl, + QualType DestType, + InitializationSequence &Sequence) { + // C++11 [dcl.init.list]p3: + // List-initialization of an object or reference of type T is defined as + // follows: + // - If T is an aggregate, aggregate initialization is performed. + if (DestType->isAggregateType()) + return false; + + // - Otherwise, if the initializer list has no elements and T is a class + // type with a default constructor, the object is value-initialized. + if (List->getNumInits() == 0) { + if (CXXConstructorDecl *DefaultConstructor = + S.LookupDefaultConstructor(DestRecordDecl)) { + if (DefaultConstructor->isDeleted() || + S.isFunctionConsideredUnavailable(DefaultConstructor)) { + // Fake an overload resolution failure. + OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); + DeclAccessPair FoundDecl = DeclAccessPair::make(DefaultConstructor, + DefaultConstructor->getAccess()); + if (FunctionTemplateDecl *ConstructorTmpl = + dyn_cast(DefaultConstructor)) + S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, + /*ExplicitArgs*/ 0, + ArrayRef(), CandidateSet, + /*SuppressUserConversions*/ false); + else + S.AddOverloadCandidate(DefaultConstructor, FoundDecl, + ArrayRef(), CandidateSet, + /*SuppressUserConversions*/ false); + Sequence.SetOverloadFailure( + InitializationSequence::FK_ListConstructorOverloadFailed, + OR_Deleted); + } else + Sequence.AddConstructorInitializationStep(DefaultConstructor, + DefaultConstructor->getAccess(), + DestType, + /*MultipleCandidates=*/false, + /*FromInitList=*/true, + /*AsInitList=*/false); + return true; + } + } + + // - Otherwise, if T is a specialization of std::initializer_list, [...] + QualType E; + if (S.isStdInitializerList(DestType, &E)) { + // Check that each individual element can be copy-constructed. But since we + // have no place to store further information, we'll recalculate everything + // later. + InitializedEntity HiddenArray = InitializedEntity::InitializeTemporary( + S.Context.getConstantArrayType(E, + llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()), + List->getNumInits()), + ArrayType::Normal, 0)); + InitializedEntity Element = InitializedEntity::InitializeElement(S.Context, + 0, HiddenArray); + for (unsigned i = 0, n = List->getNumInits(); i < n; ++i) { + Element.setElementIndex(i); + if (!S.CanPerformCopyInitialization(Element, List->getInit(i))) { + Sequence.SetFailed( + InitializationSequence::FK_InitListElementCopyFailure); + return true; + } + } + Sequence.AddStdInitializerListConstructionStep(DestType); + return true; + } + + // Not a special case. + return false; +} + +static OverloadingResult +ResolveConstructorOverload(Sema &S, SourceLocation DeclLoc, + Expr **Args, unsigned NumArgs, + OverloadCandidateSet &CandidateSet, + DeclContext::lookup_iterator Con, + DeclContext::lookup_iterator ConEnd, + OverloadCandidateSet::iterator &Best, + bool CopyInitializing, bool AllowExplicit, + bool OnlyListConstructors, bool InitListSyntax) { + CandidateSet.clear(); + + for (; Con != ConEnd; ++Con) { + NamedDecl *D = *Con; + DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); + bool SuppressUserConversions = false; + + // Find the constructor (which may be a template). + CXXConstructorDecl *Constructor = 0; + FunctionTemplateDecl *ConstructorTmpl = dyn_cast(D); + if (ConstructorTmpl) + Constructor = cast( + ConstructorTmpl->getTemplatedDecl()); + else { + Constructor = cast(D); + + // If we're performing copy initialization using a copy constructor, we + // suppress user-defined conversions on the arguments. We do the same for + // move constructors. + if ((CopyInitializing || (InitListSyntax && NumArgs == 1)) && + Constructor->isCopyOrMoveConstructor()) + SuppressUserConversions = true; + } + + if (!Constructor->isInvalidDecl() && + (AllowExplicit || !Constructor->isExplicit()) && + (!OnlyListConstructors || S.isInitListConstructor(Constructor))) { + if (ConstructorTmpl) + S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, + /*ExplicitArgs*/ 0, + llvm::makeArrayRef(Args, NumArgs), + CandidateSet, SuppressUserConversions); + else { + // C++ [over.match.copy]p1: + // - When initializing a temporary to be bound to the first parameter + // of a constructor that takes a reference to possibly cv-qualified + // T as its first argument, called with a single argument in the + // context of direct-initialization, explicit conversion functions + // are also considered. + bool AllowExplicitConv = AllowExplicit && !CopyInitializing && + NumArgs == 1 && + Constructor->isCopyOrMoveConstructor(); + S.AddOverloadCandidate(Constructor, FoundDecl, + llvm::makeArrayRef(Args, NumArgs), CandidateSet, + SuppressUserConversions, + /*PartialOverloading=*/false, + /*AllowExplicit=*/AllowExplicitConv); + } + } + } + + // Perform overload resolution and return the result. + return CandidateSet.BestViableFunction(S, DeclLoc, Best); +} + +/// \brief Attempt initialization by constructor (C++ [dcl.init]), which +/// enumerates the constructors of the initialized entity and performs overload +/// resolution to select the best. +/// If InitListSyntax is true, this is list-initialization of a non-aggregate +/// class type. +static void TryConstructorInitialization(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + Expr **Args, unsigned NumArgs, + QualType DestType, + InitializationSequence &Sequence, + bool InitListSyntax = false) { + assert((!InitListSyntax || (NumArgs == 1 && isa(Args[0]))) && + "InitListSyntax must come with a single initializer list argument."); + + // Check constructor arguments for self reference. + if (DeclaratorDecl *DD = Entity.getDecl()) + // Parameters arguments are occassionially constructed with itself, + // for instance, in recursive functions. Skip them. + if (!isa(DD)) + for (unsigned i = 0; i < NumArgs; ++i) + S.CheckSelfReference(DD, Args[i]); + + // The type we're constructing needs to be complete. + if (S.RequireCompleteType(Kind.getLocation(), DestType, 0)) { + Sequence.setIncompleteTypeFailure(DestType); + return; + } + + const RecordType *DestRecordType = DestType->getAs(); + assert(DestRecordType && "Constructor initialization requires record type"); + CXXRecordDecl *DestRecordDecl + = cast(DestRecordType->getDecl()); + + if (InitListSyntax && + TryListConstructionSpecialCases(S, cast(Args[0]), + DestRecordDecl, DestType, Sequence)) + return; + + // Build the candidate set directly in the initialization sequence + // structure, so that it will persist if we fail. + OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); + + // Determine whether we are allowed to call explicit constructors or + // explicit conversion operators. + bool AllowExplicit = Kind.AllowExplicit() || InitListSyntax; + bool CopyInitialization = Kind.getKind() == InitializationKind::IK_Copy; + + // - Otherwise, if T is a class type, constructors are considered. The + // applicable constructors are enumerated, and the best one is chosen + // through overload resolution. + DeclContext::lookup_iterator ConStart, ConEnd; + llvm::tie(ConStart, ConEnd) = S.LookupConstructors(DestRecordDecl); + + OverloadingResult Result = OR_No_Viable_Function; + OverloadCandidateSet::iterator Best; + bool AsInitializerList = false; + + // C++11 [over.match.list]p1: + // When objects of non-aggregate type T are list-initialized, overload + // resolution selects the constructor in two phases: + // - Initially, the candidate functions are the initializer-list + // constructors of the class T and the argument list consists of the + // initializer list as a single argument. + if (InitListSyntax) { + AsInitializerList = true; + Result = ResolveConstructorOverload(S, Kind.getLocation(), Args, NumArgs, + CandidateSet, ConStart, ConEnd, Best, + CopyInitialization, AllowExplicit, + /*OnlyListConstructor=*/true, + InitListSyntax); + + // Time to unwrap the init list. + InitListExpr *ILE = cast(Args[0]); + Args = ILE->getInits(); + NumArgs = ILE->getNumInits(); + } + + // C++11 [over.match.list]p1: + // - If no viable initializer-list constructor is found, overload resolution + // is performed again, where the candidate functions are all the + // constructors of the class T nad the argument list consists of the + // elements of the initializer list. + if (Result == OR_No_Viable_Function) { + AsInitializerList = false; + Result = ResolveConstructorOverload(S, Kind.getLocation(), Args, NumArgs, + CandidateSet, ConStart, ConEnd, Best, + CopyInitialization, AllowExplicit, + /*OnlyListConstructors=*/false, + InitListSyntax); + } + if (Result) { + Sequence.SetOverloadFailure(InitListSyntax ? + InitializationSequence::FK_ListConstructorOverloadFailed : + InitializationSequence::FK_ConstructorOverloadFailed, + Result); + return; + } + + // C++0x [dcl.init]p6: + // If a program calls for the default initialization of an object + // of a const-qualified type T, T shall be a class type with a + // user-provided default constructor. + if (Kind.getKind() == InitializationKind::IK_Default && + Entity.getType().isConstQualified() && + cast(Best->Function)->isImplicit()) { + Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst); + return; + } + + // C++11 [over.match.list]p1: + // In copy-list-initialization, if an explicit constructor is chosen, the + // initializer is ill-formed. + CXXConstructorDecl *CtorDecl = cast(Best->Function); + if (InitListSyntax && !Kind.AllowExplicit() && CtorDecl->isExplicit()) { + Sequence.SetFailed(InitializationSequence::FK_ExplicitConstructor); + return; + } + + // Add the constructor initialization step. Any cv-qualification conversion is + // subsumed by the initialization. + bool HadMultipleCandidates = (CandidateSet.size() > 1); + Sequence.AddConstructorInitializationStep(CtorDecl, + Best->FoundDecl.getAccess(), + DestType, HadMultipleCandidates, + InitListSyntax, AsInitializerList); +} + +static bool +ResolveOverloadedFunctionForReferenceBinding(Sema &S, + Expr *Initializer, + QualType &SourceType, + QualType &UnqualifiedSourceType, + QualType UnqualifiedTargetType, + InitializationSequence &Sequence) { + if (S.Context.getCanonicalType(UnqualifiedSourceType) == + S.Context.OverloadTy) { + DeclAccessPair Found; + bool HadMultipleCandidates = false; + if (FunctionDecl *Fn + = S.ResolveAddressOfOverloadedFunction(Initializer, + UnqualifiedTargetType, + false, Found, + &HadMultipleCandidates)) { + Sequence.AddAddressOverloadResolutionStep(Fn, Found, + HadMultipleCandidates); + SourceType = Fn->getType(); + UnqualifiedSourceType = SourceType.getUnqualifiedType(); + } else if (!UnqualifiedTargetType->isRecordType()) { + Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); + return true; + } + } + return false; +} + +static void TryReferenceInitializationCore(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + Expr *Initializer, + QualType cv1T1, QualType T1, + Qualifiers T1Quals, + QualType cv2T2, QualType T2, + Qualifiers T2Quals, + InitializationSequence &Sequence); + +static void TryListInitialization(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + InitListExpr *InitList, + InitializationSequence &Sequence); + +/// \brief Attempt list initialization of a reference. +static void TryReferenceListInitialization(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + InitListExpr *InitList, + InitializationSequence &Sequence) +{ + // First, catch C++03 where this isn't possible. + if (!S.getLangOpts().CPlusPlus0x) { + Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList); + return; + } + + QualType DestType = Entity.getType(); + QualType cv1T1 = DestType->getAs()->getPointeeType(); + Qualifiers T1Quals; + QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals); + + // Reference initialization via an initializer list works thus: + // If the initializer list consists of a single element that is + // reference-related to the referenced type, bind directly to that element + // (possibly creating temporaries). + // Otherwise, initialize a temporary with the initializer list and + // bind to that. + if (InitList->getNumInits() == 1) { + Expr *Initializer = InitList->getInit(0); + QualType cv2T2 = Initializer->getType(); + Qualifiers T2Quals; + QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals); + + // If this fails, creating a temporary wouldn't work either. + if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2, + T1, Sequence)) + return; + + SourceLocation DeclLoc = Initializer->getLocStart(); + bool dummy1, dummy2, dummy3; + Sema::ReferenceCompareResult RefRelationship + = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, dummy1, + dummy2, dummy3); + if (RefRelationship >= Sema::Ref_Related) { + // Try to bind the reference here. + TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1, + T1Quals, cv2T2, T2, T2Quals, Sequence); + if (Sequence) + Sequence.RewrapReferenceInitList(cv1T1, InitList); + return; + } + } + + // Not reference-related. Create a temporary and bind to that. + InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1); + + TryListInitialization(S, TempEntity, Kind, InitList, Sequence); + if (Sequence) { + if (DestType->isRValueReferenceType() || + (T1Quals.hasConst() && !T1Quals.hasVolatile())) + Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true); + else + Sequence.SetFailed( + InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary); + } +} + +/// \brief Attempt list initialization (C++0x [dcl.init.list]) +static void TryListInitialization(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + InitListExpr *InitList, + InitializationSequence &Sequence) { + QualType DestType = Entity.getType(); + + // C++ doesn't allow scalar initialization with more than one argument. + // But C99 complex numbers are scalars and it makes sense there. + if (S.getLangOpts().CPlusPlus && DestType->isScalarType() && + !DestType->isAnyComplexType() && InitList->getNumInits() > 1) { + Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForScalar); + return; + } + if (DestType->isReferenceType()) { + TryReferenceListInitialization(S, Entity, Kind, InitList, Sequence); + return; + } + if (DestType->isRecordType()) { + if (S.RequireCompleteType(InitList->getLocStart(), DestType, S.PDiag())) { + Sequence.setIncompleteTypeFailure(DestType); + return; + } + + if (!DestType->isAggregateType()) { + if (S.getLangOpts().CPlusPlus0x) { + Expr *Arg = InitList; + // A direct-initializer is not list-syntax, i.e. there's no special + // treatment of "A a({1, 2});". + TryConstructorInitialization(S, Entity, Kind, &Arg, 1, DestType, + Sequence, + Kind.getKind() != InitializationKind::IK_Direct); + } else + Sequence.SetFailed( + InitializationSequence::FK_InitListBadDestinationType); + return; + } + } + + InitListChecker CheckInitList(S, Entity, InitList, + DestType, /*VerifyOnly=*/true, + Kind.getKind() != InitializationKind::IK_DirectList || + !S.getLangOpts().CPlusPlus0x); + if (CheckInitList.HadError()) { + Sequence.SetFailed(InitializationSequence::FK_ListInitializationFailed); + return; + } + + // Add the list initialization step with the built init list. + Sequence.AddListInitializationStep(DestType); +} + +/// \brief Try a reference initialization that involves calling a conversion +/// function. +static OverloadingResult TryRefInitWithConversionFunction(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + Expr *Initializer, + bool AllowRValues, + InitializationSequence &Sequence) { + QualType DestType = Entity.getType(); + QualType cv1T1 = DestType->getAs()->getPointeeType(); + QualType T1 = cv1T1.getUnqualifiedType(); + QualType cv2T2 = Initializer->getType(); + QualType T2 = cv2T2.getUnqualifiedType(); + + bool DerivedToBase; + bool ObjCConversion; + bool ObjCLifetimeConversion; + assert(!S.CompareReferenceRelationship(Initializer->getLocStart(), + T1, T2, DerivedToBase, + ObjCConversion, + ObjCLifetimeConversion) && + "Must have incompatible references when binding via conversion"); + (void)DerivedToBase; + (void)ObjCConversion; + (void)ObjCLifetimeConversion; + + // Build the candidate set directly in the initialization sequence + // structure, so that it will persist if we fail. + OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); + CandidateSet.clear(); + + // Determine whether we are allowed to call explicit constructors or + // explicit conversion operators. + bool AllowExplicit = Kind.AllowExplicit(); + bool AllowExplicitConvs = Kind.allowExplicitConversionFunctions(); + + const RecordType *T1RecordType = 0; + if (AllowRValues && (T1RecordType = T1->getAs()) && + !S.RequireCompleteType(Kind.getLocation(), T1, 0)) { + // The type we're converting to is a class type. Enumerate its constructors + // to see if there is a suitable conversion. + CXXRecordDecl *T1RecordDecl = cast(T1RecordType->getDecl()); + + DeclContext::lookup_iterator Con, ConEnd; + for (llvm::tie(Con, ConEnd) = S.LookupConstructors(T1RecordDecl); + Con != ConEnd; ++Con) { + NamedDecl *D = *Con; + DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); + + // Find the constructor (which may be a template). + CXXConstructorDecl *Constructor = 0; + FunctionTemplateDecl *ConstructorTmpl = dyn_cast(D); + if (ConstructorTmpl) + Constructor = cast( + ConstructorTmpl->getTemplatedDecl()); + else + Constructor = cast(D); + + if (!Constructor->isInvalidDecl() && + Constructor->isConvertingConstructor(AllowExplicit)) { + if (ConstructorTmpl) + S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, + /*ExplicitArgs*/ 0, + Initializer, CandidateSet, + /*SuppressUserConversions=*/true); + else + S.AddOverloadCandidate(Constructor, FoundDecl, + Initializer, CandidateSet, + /*SuppressUserConversions=*/true); + } + } + } + if (T1RecordType && T1RecordType->getDecl()->isInvalidDecl()) + return OR_No_Viable_Function; + + const RecordType *T2RecordType = 0; + if ((T2RecordType = T2->getAs()) && + !S.RequireCompleteType(Kind.getLocation(), T2, 0)) { + // The type we're converting from is a class type, enumerate its conversion + // functions. + CXXRecordDecl *T2RecordDecl = cast(T2RecordType->getDecl()); + + const UnresolvedSetImpl *Conversions + = T2RecordDecl->getVisibleConversionFunctions(); + for (UnresolvedSetImpl::const_iterator I = Conversions->begin(), + E = Conversions->end(); I != E; ++I) { + NamedDecl *D = *I; + CXXRecordDecl *ActingDC = cast(D->getDeclContext()); + if (isa(D)) + D = cast(D)->getTargetDecl(); + + FunctionTemplateDecl *ConvTemplate = dyn_cast(D); + CXXConversionDecl *Conv; + if (ConvTemplate) + Conv = cast(ConvTemplate->getTemplatedDecl()); + else + Conv = cast(D); + + // If the conversion function doesn't return a reference type, + // it can't be considered for this conversion unless we're allowed to + // consider rvalues. + // FIXME: Do we need to make sure that we only consider conversion + // candidates with reference-compatible results? That might be needed to + // break recursion. + if ((AllowExplicitConvs || !Conv->isExplicit()) && + (AllowRValues || Conv->getConversionType()->isLValueReferenceType())){ + if (ConvTemplate) + S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), + ActingDC, Initializer, + DestType, CandidateSet); + else + S.AddConversionCandidate(Conv, I.getPair(), ActingDC, + Initializer, DestType, CandidateSet); + } + } + } + if (T2RecordType && T2RecordType->getDecl()->isInvalidDecl()) + return OR_No_Viable_Function; + + SourceLocation DeclLoc = Initializer->getLocStart(); + + // Perform overload resolution. If it fails, return the failed result. + OverloadCandidateSet::iterator Best; + if (OverloadingResult Result + = CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) + return Result; + + FunctionDecl *Function = Best->Function; + + // This is the overload that will actually be used for the initialization, so + // mark it as used. + S.MarkFunctionReferenced(DeclLoc, Function); + + // Compute the returned type of the conversion. + if (isa(Function)) + T2 = Function->getResultType(); + else + T2 = cv1T1; + + // Add the user-defined conversion step. + bool HadMultipleCandidates = (CandidateSet.size() > 1); + Sequence.AddUserConversionStep(Function, Best->FoundDecl, + T2.getNonLValueExprType(S.Context), + HadMultipleCandidates); + + // Determine whether we need to perform derived-to-base or + // cv-qualification adjustments. + ExprValueKind VK = VK_RValue; + if (T2->isLValueReferenceType()) + VK = VK_LValue; + else if (const RValueReferenceType *RRef = T2->getAs()) + VK = RRef->getPointeeType()->isFunctionType() ? VK_LValue : VK_XValue; + + bool NewDerivedToBase = false; + bool NewObjCConversion = false; + bool NewObjCLifetimeConversion = false; + Sema::ReferenceCompareResult NewRefRelationship + = S.CompareReferenceRelationship(DeclLoc, T1, + T2.getNonLValueExprType(S.Context), + NewDerivedToBase, NewObjCConversion, + NewObjCLifetimeConversion); + if (NewRefRelationship == Sema::Ref_Incompatible) { + // If the type we've converted to is not reference-related to the + // type we're looking for, then there is another conversion step + // we need to perform to produce a temporary of the right type + // that we'll be binding to. + ImplicitConversionSequence ICS; + ICS.setStandard(); + ICS.Standard = Best->FinalConversion; + T2 = ICS.Standard.getToType(2); + Sequence.AddConversionSequenceStep(ICS, T2); + } else if (NewDerivedToBase) + Sequence.AddDerivedToBaseCastStep( + S.Context.getQualifiedType(T1, + T2.getNonReferenceType().getQualifiers()), + VK); + else if (NewObjCConversion) + Sequence.AddObjCObjectConversionStep( + S.Context.getQualifiedType(T1, + T2.getNonReferenceType().getQualifiers())); + + if (cv1T1.getQualifiers() != T2.getNonReferenceType().getQualifiers()) + Sequence.AddQualificationConversionStep(cv1T1, VK); + + Sequence.AddReferenceBindingStep(cv1T1, !T2->isReferenceType()); + return OR_Success; +} + +static void CheckCXX98CompatAccessibleCopy(Sema &S, + const InitializedEntity &Entity, + Expr *CurInitExpr); + +/// \brief Attempt reference initialization (C++0x [dcl.init.ref]) +static void TryReferenceInitialization(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + Expr *Initializer, + InitializationSequence &Sequence) { + QualType DestType = Entity.getType(); + QualType cv1T1 = DestType->getAs()->getPointeeType(); + Qualifiers T1Quals; + QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals); + QualType cv2T2 = Initializer->getType(); + Qualifiers T2Quals; + QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals); + + // If the initializer is the address of an overloaded function, try + // to resolve the overloaded function. If all goes well, T2 is the + // type of the resulting function. + if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2, + T1, Sequence)) + return; + + // Delegate everything else to a subfunction. + TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1, + T1Quals, cv2T2, T2, T2Quals, Sequence); +} + +/// \brief Reference initialization without resolving overloaded functions. +static void TryReferenceInitializationCore(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + Expr *Initializer, + QualType cv1T1, QualType T1, + Qualifiers T1Quals, + QualType cv2T2, QualType T2, + Qualifiers T2Quals, + InitializationSequence &Sequence) { + QualType DestType = Entity.getType(); + SourceLocation DeclLoc = Initializer->getLocStart(); + // Compute some basic properties of the types and the initializer. + bool isLValueRef = DestType->isLValueReferenceType(); + bool isRValueRef = !isLValueRef; + bool DerivedToBase = false; + bool ObjCConversion = false; + bool ObjCLifetimeConversion = false; + Expr::Classification InitCategory = Initializer->Classify(S.Context); + Sema::ReferenceCompareResult RefRelationship + = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, DerivedToBase, + ObjCConversion, ObjCLifetimeConversion); + + // C++0x [dcl.init.ref]p5: + // A reference to type "cv1 T1" is initialized by an expression of type + // "cv2 T2" as follows: + // + // - If the reference is an lvalue reference and the initializer + // expression + // Note the analogous bullet points for rvlaue refs to functions. Because + // there are no function rvalues in C++, rvalue refs to functions are treated + // like lvalue refs. + OverloadingResult ConvOvlResult = OR_Success; + bool T1Function = T1->isFunctionType(); + if (isLValueRef || T1Function) { + if (InitCategory.isLValue() && + (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification || + (Kind.isCStyleOrFunctionalCast() && + RefRelationship == Sema::Ref_Related))) { + // - is an lvalue (but is not a bit-field), and "cv1 T1" is + // reference-compatible with "cv2 T2," or + // + // Per C++ [over.best.ics]p2, we don't diagnose whether the lvalue is a + // bit-field when we're determining whether the reference initialization + // can occur. However, we do pay attention to whether it is a bit-field + // to decide whether we're actually binding to a temporary created from + // the bit-field. + if (DerivedToBase) + Sequence.AddDerivedToBaseCastStep( + S.Context.getQualifiedType(T1, T2Quals), + VK_LValue); + else if (ObjCConversion) + Sequence.AddObjCObjectConversionStep( + S.Context.getQualifiedType(T1, T2Quals)); + + if (T1Quals != T2Quals) + Sequence.AddQualificationConversionStep(cv1T1, VK_LValue); + bool BindingTemporary = T1Quals.hasConst() && !T1Quals.hasVolatile() && + (Initializer->getBitField() || Initializer->refersToVectorElement()); + Sequence.AddReferenceBindingStep(cv1T1, BindingTemporary); + return; + } + + // - has a class type (i.e., T2 is a class type), where T1 is not + // reference-related to T2, and can be implicitly converted to an + // lvalue of type "cv3 T3," where "cv1 T1" is reference-compatible + // with "cv3 T3" (this conversion is selected by enumerating the + // applicable conversion functions (13.3.1.6) and choosing the best + // one through overload resolution (13.3)), + // If we have an rvalue ref to function type here, the rhs must be + // an rvalue. + if (RefRelationship == Sema::Ref_Incompatible && T2->isRecordType() && + (isLValueRef || InitCategory.isRValue())) { + ConvOvlResult = TryRefInitWithConversionFunction(S, Entity, Kind, + Initializer, + /*AllowRValues=*/isRValueRef, + Sequence); + if (ConvOvlResult == OR_Success) + return; + if (ConvOvlResult != OR_No_Viable_Function) { + Sequence.SetOverloadFailure( + InitializationSequence::FK_ReferenceInitOverloadFailed, + ConvOvlResult); + } + } + } + + // - Otherwise, the reference shall be an lvalue reference to a + // non-volatile const type (i.e., cv1 shall be const), or the reference + // shall be an rvalue reference. + if (isLValueRef && !(T1Quals.hasConst() && !T1Quals.hasVolatile())) { + if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) + Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); + else if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty()) + Sequence.SetOverloadFailure( + InitializationSequence::FK_ReferenceInitOverloadFailed, + ConvOvlResult); + else + Sequence.SetFailed(InitCategory.isLValue() + ? (RefRelationship == Sema::Ref_Related + ? InitializationSequence::FK_ReferenceInitDropsQualifiers + : InitializationSequence::FK_NonConstLValueReferenceBindingToUnrelated) + : InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary); + + return; + } + + // - If the initializer expression + // - is an xvalue, class prvalue, array prvalue, or function lvalue and + // "cv1 T1" is reference-compatible with "cv2 T2" + // Note: functions are handled below. + if (!T1Function && + (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification || + (Kind.isCStyleOrFunctionalCast() && + RefRelationship == Sema::Ref_Related)) && + (InitCategory.isXValue() || + (InitCategory.isPRValue() && T2->isRecordType()) || + (InitCategory.isPRValue() && T2->isArrayType()))) { + ExprValueKind ValueKind = InitCategory.isXValue()? VK_XValue : VK_RValue; + if (InitCategory.isPRValue() && T2->isRecordType()) { + // The corresponding bullet in C++03 [dcl.init.ref]p5 gives the + // compiler the freedom to perform a copy here or bind to the + // object, while C++0x requires that we bind directly to the + // object. Hence, we always bind to the object without making an + // extra copy. However, in C++03 requires that we check for the + // presence of a suitable copy constructor: + // + // The constructor that would be used to make the copy shall + // be callable whether or not the copy is actually done. + if (!S.getLangOpts().CPlusPlus0x && !S.getLangOpts().MicrosoftExt) + Sequence.AddExtraneousCopyToTemporary(cv2T2); + else if (S.getLangOpts().CPlusPlus0x) + CheckCXX98CompatAccessibleCopy(S, Entity, Initializer); + } + + if (DerivedToBase) + Sequence.AddDerivedToBaseCastStep(S.Context.getQualifiedType(T1, T2Quals), + ValueKind); + else if (ObjCConversion) + Sequence.AddObjCObjectConversionStep( + S.Context.getQualifiedType(T1, T2Quals)); + + if (T1Quals != T2Quals) + Sequence.AddQualificationConversionStep(cv1T1, ValueKind); + Sequence.AddReferenceBindingStep(cv1T1, + /*bindingTemporary=*/InitCategory.isPRValue()); + return; + } + + // - has a class type (i.e., T2 is a class type), where T1 is not + // reference-related to T2, and can be implicitly converted to an + // xvalue, class prvalue, or function lvalue of type "cv3 T3", + // where "cv1 T1" is reference-compatible with "cv3 T3", + if (T2->isRecordType()) { + if (RefRelationship == Sema::Ref_Incompatible) { + ConvOvlResult = TryRefInitWithConversionFunction(S, Entity, + Kind, Initializer, + /*AllowRValues=*/true, + Sequence); + if (ConvOvlResult) + Sequence.SetOverloadFailure( + InitializationSequence::FK_ReferenceInitOverloadFailed, + ConvOvlResult); + + return; + } + + Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers); + return; + } + + // - Otherwise, a temporary of type "cv1 T1" is created and initialized + // from the initializer expression using the rules for a non-reference + // copy initialization (8.5). The reference is then bound to the + // temporary. [...] + + // Determine whether we are allowed to call explicit constructors or + // explicit conversion operators. + bool AllowExplicit = Kind.AllowExplicit(); + + InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1); + + ImplicitConversionSequence ICS + = S.TryImplicitConversion(Initializer, TempEntity.getType(), + /*SuppressUserConversions*/ false, + AllowExplicit, + /*FIXME:InOverloadResolution=*/false, + /*CStyle=*/Kind.isCStyleOrFunctionalCast(), + /*AllowObjCWritebackConversion=*/false); + + if (ICS.isBad()) { + // FIXME: Use the conversion function set stored in ICS to turn + // this into an overloading ambiguity diagnostic. However, we need + // to keep that set as an OverloadCandidateSet rather than as some + // other kind of set. + if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty()) + Sequence.SetOverloadFailure( + InitializationSequence::FK_ReferenceInitOverloadFailed, + ConvOvlResult); + else if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) + Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); + else + Sequence.SetFailed(InitializationSequence::FK_ReferenceInitFailed); + return; + } else { + Sequence.AddConversionSequenceStep(ICS, TempEntity.getType()); + } + + // [...] If T1 is reference-related to T2, cv1 must be the + // same cv-qualification as, or greater cv-qualification + // than, cv2; otherwise, the program is ill-formed. + unsigned T1CVRQuals = T1Quals.getCVRQualifiers(); + unsigned T2CVRQuals = T2Quals.getCVRQualifiers(); + if (RefRelationship == Sema::Ref_Related && + (T1CVRQuals | T2CVRQuals) != T1CVRQuals) { + Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers); + return; + } + + // [...] If T1 is reference-related to T2 and the reference is an rvalue + // reference, the initializer expression shall not be an lvalue. + if (RefRelationship >= Sema::Ref_Related && !isLValueRef && + InitCategory.isLValue()) { + Sequence.SetFailed( + InitializationSequence::FK_RValueReferenceBindingToLValue); + return; + } + + Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true); + return; +} + +/// \brief Attempt character array initialization from a string literal +/// (C++ [dcl.init.string], C99 6.7.8). +static void TryStringLiteralInitialization(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + Expr *Initializer, + InitializationSequence &Sequence) { + Sequence.AddStringInitStep(Entity.getType()); +} + +/// \brief Attempt value initialization (C++ [dcl.init]p7). +static void TryValueInitialization(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + InitializationSequence &Sequence) { + // C++98 [dcl.init]p5, C++11 [dcl.init]p7: + // + // To value-initialize an object of type T means: + QualType T = Entity.getType(); + + // -- if T is an array type, then each element is value-initialized; + T = S.Context.getBaseElementType(T); + + if (const RecordType *RT = T->getAs()) { + if (CXXRecordDecl *ClassDecl = dyn_cast(RT->getDecl())) { + // C++98: + // -- if T is a class type (clause 9) with a user-declared + // constructor (12.1), then the default constructor for T is + // called (and the initialization is ill-formed if T has no + // accessible default constructor); + if (!S.getLangOpts().CPlusPlus0x) { + if (ClassDecl->hasUserDeclaredConstructor()) + // FIXME: we really want to refer to a single subobject of the array, + // but Entity doesn't have a way to capture that (yet). + return TryConstructorInitialization(S, Entity, Kind, 0, 0, + T, Sequence); + } else { + // C++11: + // -- if T is a class type (clause 9) with either no default constructor + // (12.1 [class.ctor]) or a default constructor that is user-provided + // or deleted, then the object is default-initialized; + CXXConstructorDecl *CD = S.LookupDefaultConstructor(ClassDecl); + if (!CD || !CD->getCanonicalDecl()->isDefaulted() || CD->isDeleted()) + return TryConstructorInitialization(S, Entity, Kind, 0, 0, + T, Sequence); + } + + // -- if T is a (possibly cv-qualified) non-union class type without a + // user-provided or deleted default constructor, then the object is + // zero-initialized and, if T has a non-trivial default constructor, + // default-initialized; + if ((ClassDecl->getTagKind() == TTK_Class || + ClassDecl->getTagKind() == TTK_Struct)) { + Sequence.AddZeroInitializationStep(Entity.getType()); + return TryConstructorInitialization(S, Entity, Kind, 0, 0, T, Sequence); + } + } + } + + Sequence.AddZeroInitializationStep(Entity.getType()); +} + +/// \brief Attempt default initialization (C++ [dcl.init]p6). +static void TryDefaultInitialization(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + InitializationSequence &Sequence) { + assert(Kind.getKind() == InitializationKind::IK_Default); + + // C++ [dcl.init]p6: + // To default-initialize an object of type T means: + // - if T is an array type, each element is default-initialized; + QualType DestType = S.Context.getBaseElementType(Entity.getType()); + + // - if T is a (possibly cv-qualified) class type (Clause 9), the default + // constructor for T is called (and the initialization is ill-formed if + // T has no accessible default constructor); + if (DestType->isRecordType() && S.getLangOpts().CPlusPlus) { + TryConstructorInitialization(S, Entity, Kind, 0, 0, DestType, Sequence); + return; + } + + // - otherwise, no initialization is performed. + + // If a program calls for the default initialization of an object of + // a const-qualified type T, T shall be a class type with a user-provided + // default constructor. + if (DestType.isConstQualified() && S.getLangOpts().CPlusPlus) { + Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst); + return; + } + + // If the destination type has a lifetime property, zero-initialize it. + if (DestType.getQualifiers().hasObjCLifetime()) { + Sequence.AddZeroInitializationStep(Entity.getType()); + return; + } +} + +/// \brief Attempt a user-defined conversion between two types (C++ [dcl.init]), +/// which enumerates all conversion functions and performs overload resolution +/// to select the best. +static void TryUserDefinedConversion(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + Expr *Initializer, + InitializationSequence &Sequence) { + QualType DestType = Entity.getType(); + assert(!DestType->isReferenceType() && "References are handled elsewhere"); + QualType SourceType = Initializer->getType(); + assert((DestType->isRecordType() || SourceType->isRecordType()) && + "Must have a class type to perform a user-defined conversion"); + + // Build the candidate set directly in the initialization sequence + // structure, so that it will persist if we fail. + OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); + CandidateSet.clear(); + + // Determine whether we are allowed to call explicit constructors or + // explicit conversion operators. + bool AllowExplicit = Kind.AllowExplicit(); + + if (const RecordType *DestRecordType = DestType->getAs()) { + // The type we're converting to is a class type. Enumerate its constructors + // to see if there is a suitable conversion. + CXXRecordDecl *DestRecordDecl + = cast(DestRecordType->getDecl()); + + // Try to complete the type we're converting to. + if (!S.RequireCompleteType(Kind.getLocation(), DestType, 0)) { + DeclContext::lookup_iterator Con, ConEnd; + for (llvm::tie(Con, ConEnd) = S.LookupConstructors(DestRecordDecl); + Con != ConEnd; ++Con) { + NamedDecl *D = *Con; + DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); + + // Find the constructor (which may be a template). + CXXConstructorDecl *Constructor = 0; + FunctionTemplateDecl *ConstructorTmpl + = dyn_cast(D); + if (ConstructorTmpl) + Constructor = cast( + ConstructorTmpl->getTemplatedDecl()); + else + Constructor = cast(D); + + if (!Constructor->isInvalidDecl() && + Constructor->isConvertingConstructor(AllowExplicit)) { + if (ConstructorTmpl) + S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, + /*ExplicitArgs*/ 0, + Initializer, CandidateSet, + /*SuppressUserConversions=*/true); + else + S.AddOverloadCandidate(Constructor, FoundDecl, + Initializer, CandidateSet, + /*SuppressUserConversions=*/true); + } + } + } + } + + SourceLocation DeclLoc = Initializer->getLocStart(); + + if (const RecordType *SourceRecordType = SourceType->getAs()) { + // The type we're converting from is a class type, enumerate its conversion + // functions. + + // We can only enumerate the conversion functions for a complete type; if + // the type isn't complete, simply skip this step. + if (!S.RequireCompleteType(DeclLoc, SourceType, 0)) { + CXXRecordDecl *SourceRecordDecl + = cast(SourceRecordType->getDecl()); + + const UnresolvedSetImpl *Conversions + = SourceRecordDecl->getVisibleConversionFunctions(); + for (UnresolvedSetImpl::const_iterator I = Conversions->begin(), + E = Conversions->end(); + I != E; ++I) { + NamedDecl *D = *I; + CXXRecordDecl *ActingDC = cast(D->getDeclContext()); + if (isa(D)) + D = cast(D)->getTargetDecl(); + + FunctionTemplateDecl *ConvTemplate = dyn_cast(D); + CXXConversionDecl *Conv; + if (ConvTemplate) + Conv = cast(ConvTemplate->getTemplatedDecl()); + else + Conv = cast(D); + + if (AllowExplicit || !Conv->isExplicit()) { + if (ConvTemplate) + S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), + ActingDC, Initializer, DestType, + CandidateSet); + else + S.AddConversionCandidate(Conv, I.getPair(), ActingDC, + Initializer, DestType, CandidateSet); + } + } + } + } + + // Perform overload resolution. If it fails, return the failed result. + OverloadCandidateSet::iterator Best; + if (OverloadingResult Result + = CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) { + Sequence.SetOverloadFailure( + InitializationSequence::FK_UserConversionOverloadFailed, + Result); + return; + } + + FunctionDecl *Function = Best->Function; + S.MarkFunctionReferenced(DeclLoc, Function); + bool HadMultipleCandidates = (CandidateSet.size() > 1); + + if (isa(Function)) { + // Add the user-defined conversion step. Any cv-qualification conversion is + // subsumed by the initialization. Per DR5, the created temporary is of the + // cv-unqualified type of the destination. + Sequence.AddUserConversionStep(Function, Best->FoundDecl, + DestType.getUnqualifiedType(), + HadMultipleCandidates); + return; + } + + // Add the user-defined conversion step that calls the conversion function. + QualType ConvType = Function->getCallResultType(); + if (ConvType->getAs()) { + // If we're converting to a class type, there may be an copy of + // the resulting temporary object (possible to create an object of + // a base class type). That copy is not a separate conversion, so + // we just make a note of the actual destination type (possibly a + // base class of the type returned by the conversion function) and + // let the user-defined conversion step handle the conversion. + Sequence.AddUserConversionStep(Function, Best->FoundDecl, DestType, + HadMultipleCandidates); + return; + } + + Sequence.AddUserConversionStep(Function, Best->FoundDecl, ConvType, + HadMultipleCandidates); + + // If the conversion following the call to the conversion function + // is interesting, add it as a separate step. + if (Best->FinalConversion.First || Best->FinalConversion.Second || + Best->FinalConversion.Third) { + ImplicitConversionSequence ICS; + ICS.setStandard(); + ICS.Standard = Best->FinalConversion; + Sequence.AddConversionSequenceStep(ICS, DestType); + } +} + +/// The non-zero enum values here are indexes into diagnostic alternatives. +enum InvalidICRKind { IIK_okay, IIK_nonlocal, IIK_nonscalar }; + +/// Determines whether this expression is an acceptable ICR source. +static InvalidICRKind isInvalidICRSource(ASTContext &C, Expr *e, + bool isAddressOf) { + // Skip parens. + e = e->IgnoreParens(); + + // Skip address-of nodes. + if (UnaryOperator *op = dyn_cast(e)) { + if (op->getOpcode() == UO_AddrOf) + return isInvalidICRSource(C, op->getSubExpr(), /*addressof*/ true); + + // Skip certain casts. + } else if (CastExpr *ce = dyn_cast(e)) { + switch (ce->getCastKind()) { + case CK_Dependent: + case CK_BitCast: + case CK_LValueBitCast: + case CK_NoOp: + return isInvalidICRSource(C, ce->getSubExpr(), isAddressOf); + + case CK_ArrayToPointerDecay: + return IIK_nonscalar; + + case CK_NullToPointer: + return IIK_okay; + + default: + break; + } + + // If we have a declaration reference, it had better be a local variable. + } else if (isa(e)) { + if (!isAddressOf) return IIK_nonlocal; + + VarDecl *var = dyn_cast(cast(e)->getDecl()); + if (!var) return IIK_nonlocal; + + return (var->hasLocalStorage() ? IIK_okay : IIK_nonlocal); + + // If we have a conditional operator, check both sides. + } else if (ConditionalOperator *cond = dyn_cast(e)) { + if (InvalidICRKind iik = isInvalidICRSource(C, cond->getLHS(), isAddressOf)) + return iik; + + return isInvalidICRSource(C, cond->getRHS(), isAddressOf); + + // These are never scalar. + } else if (isa(e)) { + return IIK_nonscalar; + + // Otherwise, it needs to be a null pointer constant. + } else { + return (e->isNullPointerConstant(C, Expr::NPC_ValueDependentIsNull) + ? IIK_okay : IIK_nonlocal); + } + + return IIK_nonlocal; +} + +/// Check whether the given expression is a valid operand for an +/// indirect copy/restore. +static void checkIndirectCopyRestoreSource(Sema &S, Expr *src) { + assert(src->isRValue()); + + InvalidICRKind iik = isInvalidICRSource(S.Context, src, false); + if (iik == IIK_okay) return; + + S.Diag(src->getExprLoc(), diag::err_arc_nonlocal_writeback) + << ((unsigned) iik - 1) // shift index into diagnostic explanations + << src->getSourceRange(); +} + +/// \brief Determine whether we have compatible array types for the +/// purposes of GNU by-copy array initialization. +static bool hasCompatibleArrayTypes(ASTContext &Context, + const ArrayType *Dest, + const ArrayType *Source) { + // If the source and destination array types are equivalent, we're + // done. + if (Context.hasSameType(QualType(Dest, 0), QualType(Source, 0))) + return true; + + // Make sure that the element types are the same. + if (!Context.hasSameType(Dest->getElementType(), Source->getElementType())) + return false; + + // The only mismatch we allow is when the destination is an + // incomplete array type and the source is a constant array type. + return Source->isConstantArrayType() && Dest->isIncompleteArrayType(); +} + +static bool tryObjCWritebackConversion(Sema &S, + InitializationSequence &Sequence, + const InitializedEntity &Entity, + Expr *Initializer) { + bool ArrayDecay = false; + QualType ArgType = Initializer->getType(); + QualType ArgPointee; + if (const ArrayType *ArgArrayType = S.Context.getAsArrayType(ArgType)) { + ArrayDecay = true; + ArgPointee = ArgArrayType->getElementType(); + ArgType = S.Context.getPointerType(ArgPointee); + } + + // Handle write-back conversion. + QualType ConvertedArgType; + if (!S.isObjCWritebackConversion(ArgType, Entity.getType(), + ConvertedArgType)) + return false; + + // We should copy unless we're passing to an argument explicitly + // marked 'out'. + bool ShouldCopy = true; + if (ParmVarDecl *param = cast_or_null(Entity.getDecl())) + ShouldCopy = (param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out); + + // Do we need an lvalue conversion? + if (ArrayDecay || Initializer->isGLValue()) { + ImplicitConversionSequence ICS; + ICS.setStandard(); + ICS.Standard.setAsIdentityConversion(); + + QualType ResultType; + if (ArrayDecay) { + ICS.Standard.First = ICK_Array_To_Pointer; + ResultType = S.Context.getPointerType(ArgPointee); + } else { + ICS.Standard.First = ICK_Lvalue_To_Rvalue; + ResultType = Initializer->getType().getNonLValueExprType(S.Context); + } + + Sequence.AddConversionSequenceStep(ICS, ResultType); + } + + Sequence.AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy); + return true; +} + +InitializationSequence::InitializationSequence(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + Expr **Args, + unsigned NumArgs) + : FailedCandidateSet(Kind.getLocation()) { + ASTContext &Context = S.Context; + + // C++0x [dcl.init]p16: + // The semantics of initializers are as follows. The destination type is + // the type of the object or reference being initialized and the source + // type is the type of the initializer expression. The source type is not + // defined when the initializer is a braced-init-list or when it is a + // parenthesized list of expressions. + QualType DestType = Entity.getType(); + + if (DestType->isDependentType() || + Expr::hasAnyTypeDependentArguments(llvm::makeArrayRef(Args, NumArgs))) { + SequenceKind = DependentSequence; + return; + } + + // Almost everything is a normal sequence. + setSequenceKind(NormalSequence); + + for (unsigned I = 0; I != NumArgs; ++I) + if (Args[I]->getType()->isNonOverloadPlaceholderType()) { + // FIXME: should we be doing this here? + ExprResult result = S.CheckPlaceholderExpr(Args[I]); + if (result.isInvalid()) { + SetFailed(FK_PlaceholderType); + return; + } + Args[I] = result.take(); + } + + + QualType SourceType; + Expr *Initializer = 0; + if (NumArgs == 1) { + Initializer = Args[0]; + if (!isa(Initializer)) + SourceType = Initializer->getType(); + } + + // - If the initializer is a (non-parenthesized) braced-init-list, the + // object is list-initialized (8.5.4). + if (Kind.getKind() != InitializationKind::IK_Direct) { + if (InitListExpr *InitList = dyn_cast_or_null(Initializer)) { + TryListInitialization(S, Entity, Kind, InitList, *this); + return; + } + } + + // - If the destination type is a reference type, see 8.5.3. + if (DestType->isReferenceType()) { + // C++0x [dcl.init.ref]p1: + // A variable declared to be a T& or T&&, that is, "reference to type T" + // (8.3.2), shall be initialized by an object, or function, of type T or + // by an object that can be converted into a T. + // (Therefore, multiple arguments are not permitted.) + if (NumArgs != 1) + SetFailed(FK_TooManyInitsForReference); + else + TryReferenceInitialization(S, Entity, Kind, Args[0], *this); + return; + } + + // - If the initializer is (), the object is value-initialized. + if (Kind.getKind() == InitializationKind::IK_Value || + (Kind.getKind() == InitializationKind::IK_Direct && NumArgs == 0)) { + TryValueInitialization(S, Entity, Kind, *this); + return; + } + + // Handle default initialization. + if (Kind.getKind() == InitializationKind::IK_Default) { + TryDefaultInitialization(S, Entity, Kind, *this); + return; + } + + // - If the destination type is an array of characters, an array of + // char16_t, an array of char32_t, or an array of wchar_t, and the + // initializer is a string literal, see 8.5.2. + // - Otherwise, if the destination type is an array, the program is + // ill-formed. + if (const ArrayType *DestAT = Context.getAsArrayType(DestType)) { + if (Initializer && isa(DestAT)) { + SetFailed(FK_VariableLengthArrayHasInitializer); + return; + } + + if (Initializer && IsStringInit(Initializer, DestAT, Context)) { + TryStringLiteralInitialization(S, Entity, Kind, Initializer, *this); + return; + } + + // Note: as an GNU C extension, we allow initialization of an + // array from a compound literal that creates an array of the same + // type, so long as the initializer has no side effects. + if (!S.getLangOpts().CPlusPlus && Initializer && + isa(Initializer->IgnoreParens()) && + Initializer->getType()->isArrayType()) { + const ArrayType *SourceAT + = Context.getAsArrayType(Initializer->getType()); + if (!hasCompatibleArrayTypes(S.Context, DestAT, SourceAT)) + SetFailed(FK_ArrayTypeMismatch); + else if (Initializer->HasSideEffects(S.Context)) + SetFailed(FK_NonConstantArrayInit); + else { + AddArrayInitStep(DestType); + } + } + // Note: as a GNU C++ extension, we allow initialization of a + // class member from a parenthesized initializer list. + else if (S.getLangOpts().CPlusPlus && + Entity.getKind() == InitializedEntity::EK_Member && + Initializer && isa(Initializer)) { + TryListInitialization(S, Entity, Kind, cast(Initializer), + *this); + AddParenthesizedArrayInitStep(DestType); + } else if (DestAT->getElementType()->isAnyCharacterType()) + SetFailed(FK_ArrayNeedsInitListOrStringLiteral); + else + SetFailed(FK_ArrayNeedsInitList); + + return; + } + + // Determine whether we should consider writeback conversions for + // Objective-C ARC. + bool allowObjCWritebackConversion = S.getLangOpts().ObjCAutoRefCount && + Entity.getKind() == InitializedEntity::EK_Parameter; + + // We're at the end of the line for C: it's either a write-back conversion + // or it's a C assignment. There's no need to check anything else. + if (!S.getLangOpts().CPlusPlus) { + // If allowed, check whether this is an Objective-C writeback conversion. + if (allowObjCWritebackConversion && + tryObjCWritebackConversion(S, *this, Entity, Initializer)) { + return; + } + + // Handle initialization in C + AddCAssignmentStep(DestType); + MaybeProduceObjCObject(S, *this, Entity); + return; + } + + assert(S.getLangOpts().CPlusPlus); + + // - If the destination type is a (possibly cv-qualified) class type: + if (DestType->isRecordType()) { + // - If the initialization is direct-initialization, or if it is + // copy-initialization where the cv-unqualified version of the + // source type is the same class as, or a derived class of, the + // class of the destination, constructors are considered. [...] + if (Kind.getKind() == InitializationKind::IK_Direct || + (Kind.getKind() == InitializationKind::IK_Copy && + (Context.hasSameUnqualifiedType(SourceType, DestType) || + S.IsDerivedFrom(SourceType, DestType)))) + TryConstructorInitialization(S, Entity, Kind, Args, NumArgs, + Entity.getType(), *this); + // - Otherwise (i.e., for the remaining copy-initialization cases), + // user-defined conversion sequences that can convert from the source + // type to the destination type or (when a conversion function is + // used) to a derived class thereof are enumerated as described in + // 13.3.1.4, and the best one is chosen through overload resolution + // (13.3). + else + TryUserDefinedConversion(S, Entity, Kind, Initializer, *this); + return; + } + + if (NumArgs > 1) { + SetFailed(FK_TooManyInitsForScalar); + return; + } + assert(NumArgs == 1 && "Zero-argument case handled above"); + + // - Otherwise, if the source type is a (possibly cv-qualified) class + // type, conversion functions are considered. + if (!SourceType.isNull() && SourceType->isRecordType()) { + TryUserDefinedConversion(S, Entity, Kind, Initializer, *this); + MaybeProduceObjCObject(S, *this, Entity); + return; + } + + // - Otherwise, the initial value of the object being initialized is the + // (possibly converted) value of the initializer expression. Standard + // conversions (Clause 4) will be used, if necessary, to convert the + // initializer expression to the cv-unqualified version of the + // destination type; no user-defined conversions are considered. + + ImplicitConversionSequence ICS + = S.TryImplicitConversion(Initializer, Entity.getType(), + /*SuppressUserConversions*/true, + /*AllowExplicitConversions*/ false, + /*InOverloadResolution*/ false, + /*CStyle=*/Kind.isCStyleOrFunctionalCast(), + allowObjCWritebackConversion); + + if (ICS.isStandard() && + ICS.Standard.Second == ICK_Writeback_Conversion) { + // Objective-C ARC writeback conversion. + + // We should copy unless we're passing to an argument explicitly + // marked 'out'. + bool ShouldCopy = true; + if (ParmVarDecl *Param = cast_or_null(Entity.getDecl())) + ShouldCopy = (Param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out); + + // If there was an lvalue adjustment, add it as a separate conversion. + if (ICS.Standard.First == ICK_Array_To_Pointer || + ICS.Standard.First == ICK_Lvalue_To_Rvalue) { + ImplicitConversionSequence LvalueICS; + LvalueICS.setStandard(); + LvalueICS.Standard.setAsIdentityConversion(); + LvalueICS.Standard.setAllToTypes(ICS.Standard.getToType(0)); + LvalueICS.Standard.First = ICS.Standard.First; + AddConversionSequenceStep(LvalueICS, ICS.Standard.getToType(0)); + } + + AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy); + } else if (ICS.isBad()) { + DeclAccessPair dap; + if (Initializer->getType() == Context.OverloadTy && + !S.ResolveAddressOfOverloadedFunction(Initializer + , DestType, false, dap)) + SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); + else + SetFailed(InitializationSequence::FK_ConversionFailed); + } else { + AddConversionSequenceStep(ICS, Entity.getType()); + + MaybeProduceObjCObject(S, *this, Entity); + } +} + +InitializationSequence::~InitializationSequence() { + for (SmallVectorImpl::iterator Step = Steps.begin(), + StepEnd = Steps.end(); + Step != StepEnd; ++Step) + Step->Destroy(); +} + +//===----------------------------------------------------------------------===// +// Perform initialization +//===----------------------------------------------------------------------===// +static Sema::AssignmentAction +getAssignmentAction(const InitializedEntity &Entity) { + switch(Entity.getKind()) { + case InitializedEntity::EK_Variable: + case InitializedEntity::EK_New: + case InitializedEntity::EK_Exception: + case InitializedEntity::EK_Base: + case InitializedEntity::EK_Delegating: + return Sema::AA_Initializing; + + case InitializedEntity::EK_Parameter: + if (Entity.getDecl() && + isa(Entity.getDecl()->getDeclContext())) + return Sema::AA_Sending; + + return Sema::AA_Passing; + + case InitializedEntity::EK_Result: + return Sema::AA_Returning; + + case InitializedEntity::EK_Temporary: + // FIXME: Can we tell apart casting vs. converting? + return Sema::AA_Casting; + + case InitializedEntity::EK_Member: + case InitializedEntity::EK_ArrayElement: + case InitializedEntity::EK_VectorElement: + case InitializedEntity::EK_ComplexElement: + case InitializedEntity::EK_BlockElement: + case InitializedEntity::EK_LambdaCapture: + return Sema::AA_Initializing; + } + + llvm_unreachable("Invalid EntityKind!"); +} + +/// \brief Whether we should binding a created object as a temporary when +/// initializing the given entity. +static bool shouldBindAsTemporary(const InitializedEntity &Entity) { + switch (Entity.getKind()) { + case InitializedEntity::EK_ArrayElement: + case InitializedEntity::EK_Member: + case InitializedEntity::EK_Result: + case InitializedEntity::EK_New: + case InitializedEntity::EK_Variable: + case InitializedEntity::EK_Base: + case InitializedEntity::EK_Delegating: + case InitializedEntity::EK_VectorElement: + case InitializedEntity::EK_ComplexElement: + case InitializedEntity::EK_Exception: + case InitializedEntity::EK_BlockElement: + case InitializedEntity::EK_LambdaCapture: + return false; + + case InitializedEntity::EK_Parameter: + case InitializedEntity::EK_Temporary: + return true; + } + + llvm_unreachable("missed an InitializedEntity kind?"); +} + +/// \brief Whether the given entity, when initialized with an object +/// created for that initialization, requires destruction. +static bool shouldDestroyTemporary(const InitializedEntity &Entity) { + switch (Entity.getKind()) { + case InitializedEntity::EK_Member: + case InitializedEntity::EK_Result: + case InitializedEntity::EK_New: + case InitializedEntity::EK_Base: + case InitializedEntity::EK_Delegating: + case InitializedEntity::EK_VectorElement: + case InitializedEntity::EK_ComplexElement: + case InitializedEntity::EK_BlockElement: + case InitializedEntity::EK_LambdaCapture: + return false; + + case InitializedEntity::EK_Variable: + case InitializedEntity::EK_Parameter: + case InitializedEntity::EK_Temporary: + case InitializedEntity::EK_ArrayElement: + case InitializedEntity::EK_Exception: + return true; + } + + llvm_unreachable("missed an InitializedEntity kind?"); +} + +/// \brief Look for copy and move constructors and constructor templates, for +/// copying an object via direct-initialization (per C++11 [dcl.init]p16). +static void LookupCopyAndMoveConstructors(Sema &S, + OverloadCandidateSet &CandidateSet, + CXXRecordDecl *Class, + Expr *CurInitExpr) { + DeclContext::lookup_iterator Con, ConEnd; + for (llvm::tie(Con, ConEnd) = S.LookupConstructors(Class); + Con != ConEnd; ++Con) { + CXXConstructorDecl *Constructor = 0; + + if ((Constructor = dyn_cast(*Con))) { + // Handle copy/moveconstructors, only. + if (!Constructor || Constructor->isInvalidDecl() || + !Constructor->isCopyOrMoveConstructor() || + !Constructor->isConvertingConstructor(/*AllowExplicit=*/true)) + continue; + + DeclAccessPair FoundDecl + = DeclAccessPair::make(Constructor, Constructor->getAccess()); + S.AddOverloadCandidate(Constructor, FoundDecl, + CurInitExpr, CandidateSet); + continue; + } + + // Handle constructor templates. + FunctionTemplateDecl *ConstructorTmpl = cast(*Con); + if (ConstructorTmpl->isInvalidDecl()) + continue; + + Constructor = cast( + ConstructorTmpl->getTemplatedDecl()); + if (!Constructor->isConvertingConstructor(/*AllowExplicit=*/true)) + continue; + + // FIXME: Do we need to limit this to copy-constructor-like + // candidates? + DeclAccessPair FoundDecl + = DeclAccessPair::make(ConstructorTmpl, ConstructorTmpl->getAccess()); + S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 0, + CurInitExpr, CandidateSet, true); + } +} + +/// \brief Get the location at which initialization diagnostics should appear. +static SourceLocation getInitializationLoc(const InitializedEntity &Entity, + Expr *Initializer) { + switch (Entity.getKind()) { + case InitializedEntity::EK_Result: + return Entity.getReturnLoc(); + + case InitializedEntity::EK_Exception: + return Entity.getThrowLoc(); + + case InitializedEntity::EK_Variable: + return Entity.getDecl()->getLocation(); + + case InitializedEntity::EK_LambdaCapture: + return Entity.getCaptureLoc(); + + case InitializedEntity::EK_ArrayElement: + case InitializedEntity::EK_Member: + case InitializedEntity::EK_Parameter: + case InitializedEntity::EK_Temporary: + case InitializedEntity::EK_New: + case InitializedEntity::EK_Base: + case InitializedEntity::EK_Delegating: + case InitializedEntity::EK_VectorElement: + case InitializedEntity::EK_ComplexElement: + case InitializedEntity::EK_BlockElement: + return Initializer->getLocStart(); + } + llvm_unreachable("missed an InitializedEntity kind?"); +} + +/// \brief Make a (potentially elidable) temporary copy of the object +/// provided by the given initializer by calling the appropriate copy +/// constructor. +/// +/// \param S The Sema object used for type-checking. +/// +/// \param T The type of the temporary object, which must either be +/// the type of the initializer expression or a superclass thereof. +/// +/// \param Enter The entity being initialized. +/// +/// \param CurInit The initializer expression. +/// +/// \param IsExtraneousCopy Whether this is an "extraneous" copy that +/// is permitted in C++03 (but not C++0x) when binding a reference to +/// an rvalue. +/// +/// \returns An expression that copies the initializer expression into +/// a temporary object, or an error expression if a copy could not be +/// created. +static ExprResult CopyObject(Sema &S, + QualType T, + const InitializedEntity &Entity, + ExprResult CurInit, + bool IsExtraneousCopy) { + // Determine which class type we're copying to. + Expr *CurInitExpr = (Expr *)CurInit.get(); + CXXRecordDecl *Class = 0; + if (const RecordType *Record = T->getAs()) + Class = cast(Record->getDecl()); + if (!Class) + return move(CurInit); + + // C++0x [class.copy]p32: + // When certain criteria are met, an implementation is allowed to + // omit the copy/move construction of a class object, even if the + // copy/move constructor and/or destructor for the object have + // side effects. [...] + // - when a temporary class object that has not been bound to a + // reference (12.2) would be copied/moved to a class object + // with the same cv-unqualified type, the copy/move operation + // can be omitted by constructing the temporary object + // directly into the target of the omitted copy/move + // + // Note that the other three bullets are handled elsewhere. Copy + // elision for return statements and throw expressions are handled as part + // of constructor initialization, while copy elision for exception handlers + // is handled by the run-time. + bool Elidable = CurInitExpr->isTemporaryObject(S.Context, Class); + SourceLocation Loc = getInitializationLoc(Entity, CurInit.get()); + + // Make sure that the type we are copying is complete. + if (S.RequireCompleteType(Loc, T, S.PDiag(diag::err_temp_copy_incomplete))) + return move(CurInit); + + // Perform overload resolution using the class's copy/move constructors. + // Only consider constructors and constructor templates. Per + // C++0x [dcl.init]p16, second bullet to class types, this initialization + // is direct-initialization. + OverloadCandidateSet CandidateSet(Loc); + LookupCopyAndMoveConstructors(S, CandidateSet, Class, CurInitExpr); + + bool HadMultipleCandidates = (CandidateSet.size() > 1); + + OverloadCandidateSet::iterator Best; + switch (CandidateSet.BestViableFunction(S, Loc, Best)) { + case OR_Success: + break; + + case OR_No_Viable_Function: + S.Diag(Loc, IsExtraneousCopy && !S.isSFINAEContext() + ? diag::ext_rvalue_to_reference_temp_copy_no_viable + : diag::err_temp_copy_no_viable) + << (int)Entity.getKind() << CurInitExpr->getType() + << CurInitExpr->getSourceRange(); + CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr); + if (!IsExtraneousCopy || S.isSFINAEContext()) + return ExprError(); + return move(CurInit); + + case OR_Ambiguous: + S.Diag(Loc, diag::err_temp_copy_ambiguous) + << (int)Entity.getKind() << CurInitExpr->getType() + << CurInitExpr->getSourceRange(); + CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr); + return ExprError(); + + case OR_Deleted: + S.Diag(Loc, diag::err_temp_copy_deleted) + << (int)Entity.getKind() << CurInitExpr->getType() + << CurInitExpr->getSourceRange(); + S.NoteDeletedFunction(Best->Function); + return ExprError(); + } + + CXXConstructorDecl *Constructor = cast(Best->Function); + ASTOwningVector ConstructorArgs(S); + CurInit.release(); // Ownership transferred into MultiExprArg, below. + + S.CheckConstructorAccess(Loc, Constructor, Entity, + Best->FoundDecl.getAccess(), IsExtraneousCopy); + + if (IsExtraneousCopy) { + // If this is a totally extraneous copy for C++03 reference + // binding purposes, just return the original initialization + // expression. We don't generate an (elided) copy operation here + // because doing so would require us to pass down a flag to avoid + // infinite recursion, where each step adds another extraneous, + // elidable copy. + + // Instantiate the default arguments of any extra parameters in + // the selected copy constructor, as if we were going to create a + // proper call to the copy constructor. + for (unsigned I = 1, N = Constructor->getNumParams(); I != N; ++I) { + ParmVarDecl *Parm = Constructor->getParamDecl(I); + if (S.RequireCompleteType(Loc, Parm->getType(), + S.PDiag(diag::err_call_incomplete_argument))) + break; + + // Build the default argument expression; we don't actually care + // if this succeeds or not, because this routine will complain + // if there was a problem. + S.BuildCXXDefaultArgExpr(Loc, Constructor, Parm); + } + + return S.Owned(CurInitExpr); + } + + S.MarkFunctionReferenced(Loc, Constructor); + + // Determine the arguments required to actually perform the + // constructor call (we might have derived-to-base conversions, or + // the copy constructor may have default arguments). + if (S.CompleteConstructorCall(Constructor, MultiExprArg(&CurInitExpr, 1), + Loc, ConstructorArgs)) + return ExprError(); + + // Actually perform the constructor call. + CurInit = S.BuildCXXConstructExpr(Loc, T, Constructor, Elidable, + move_arg(ConstructorArgs), + HadMultipleCandidates, + /*ZeroInit*/ false, + CXXConstructExpr::CK_Complete, + SourceRange()); + + // If we're supposed to bind temporaries, do so. + if (!CurInit.isInvalid() && shouldBindAsTemporary(Entity)) + CurInit = S.MaybeBindToTemporary(CurInit.takeAs()); + return move(CurInit); +} + +/// \brief Check whether elidable copy construction for binding a reference to +/// a temporary would have succeeded if we were building in C++98 mode, for +/// -Wc++98-compat. +static void CheckCXX98CompatAccessibleCopy(Sema &S, + const InitializedEntity &Entity, + Expr *CurInitExpr) { + assert(S.getLangOpts().CPlusPlus0x); + + const RecordType *Record = CurInitExpr->getType()->getAs(); + if (!Record) + return; + + SourceLocation Loc = getInitializationLoc(Entity, CurInitExpr); + if (S.Diags.getDiagnosticLevel(diag::warn_cxx98_compat_temp_copy, Loc) + == DiagnosticsEngine::Ignored) + return; + + // Find constructors which would have been considered. + OverloadCandidateSet CandidateSet(Loc); + LookupCopyAndMoveConstructors( + S, CandidateSet, cast(Record->getDecl()), CurInitExpr); + + // Perform overload resolution. + OverloadCandidateSet::iterator Best; + OverloadingResult OR = CandidateSet.BestViableFunction(S, Loc, Best); + + PartialDiagnostic Diag = S.PDiag(diag::warn_cxx98_compat_temp_copy) + << OR << (int)Entity.getKind() << CurInitExpr->getType() + << CurInitExpr->getSourceRange(); + + switch (OR) { + case OR_Success: + S.CheckConstructorAccess(Loc, cast(Best->Function), + Entity, Best->FoundDecl.getAccess(), Diag); + // FIXME: Check default arguments as far as that's possible. + break; + + case OR_No_Viable_Function: + S.Diag(Loc, Diag); + CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr); + break; + + case OR_Ambiguous: + S.Diag(Loc, Diag); + CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr); + break; + + case OR_Deleted: + S.Diag(Loc, Diag); + S.NoteDeletedFunction(Best->Function); + break; + } +} + +void InitializationSequence::PrintInitLocationNote(Sema &S, + const InitializedEntity &Entity) { + if (Entity.getKind() == InitializedEntity::EK_Parameter && Entity.getDecl()) { + if (Entity.getDecl()->getLocation().isInvalid()) + return; + + if (Entity.getDecl()->getDeclName()) + S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_named_here) + << Entity.getDecl()->getDeclName(); + else + S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_here); + } +} + +static bool isReferenceBinding(const InitializationSequence::Step &s) { + return s.Kind == InitializationSequence::SK_BindReference || + s.Kind == InitializationSequence::SK_BindReferenceToTemporary; +} + +static ExprResult +PerformConstructorInitialization(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + MultiExprArg Args, + const InitializationSequence::Step& Step, + bool &ConstructorInitRequiresZeroInit) { + unsigned NumArgs = Args.size(); + CXXConstructorDecl *Constructor + = cast(Step.Function.Function); + bool HadMultipleCandidates = Step.Function.HadMultipleCandidates; + + // Build a call to the selected constructor. + ASTOwningVector ConstructorArgs(S); + SourceLocation Loc = (Kind.isCopyInit() && Kind.getEqualLoc().isValid()) + ? Kind.getEqualLoc() + : Kind.getLocation(); + + if (Kind.getKind() == InitializationKind::IK_Default) { + // Force even a trivial, implicit default constructor to be + // semantically checked. We do this explicitly because we don't build + // the definition for completely trivial constructors. + assert(Constructor->getParent() && "No parent class for constructor."); + if (Constructor->isDefaulted() && Constructor->isDefaultConstructor() && + Constructor->isTrivial() && !Constructor->isUsed(false)) + S.DefineImplicitDefaultConstructor(Loc, Constructor); + } + + ExprResult CurInit = S.Owned((Expr *)0); + + // C++ [over.match.copy]p1: + // - When initializing a temporary to be bound to the first parameter + // of a constructor that takes a reference to possibly cv-qualified + // T as its first argument, called with a single argument in the + // context of direct-initialization, explicit conversion functions + // are also considered. + bool AllowExplicitConv = Kind.AllowExplicit() && !Kind.isCopyInit() && + Args.size() == 1 && + Constructor->isCopyOrMoveConstructor(); + + // Determine the arguments required to actually perform the constructor + // call. + if (S.CompleteConstructorCall(Constructor, move(Args), + Loc, ConstructorArgs, + AllowExplicitConv)) + return ExprError(); + + + if (Entity.getKind() == InitializedEntity::EK_Temporary && + (Kind.getKind() == InitializationKind::IK_DirectList || + (NumArgs != 1 && // FIXME: Hack to work around cast weirdness + (Kind.getKind() == InitializationKind::IK_Direct || + Kind.getKind() == InitializationKind::IK_Value)))) { + // An explicitly-constructed temporary, e.g., X(1, 2). + unsigned NumExprs = ConstructorArgs.size(); + Expr **Exprs = (Expr **)ConstructorArgs.take(); + S.MarkFunctionReferenced(Loc, Constructor); + S.DiagnoseUseOfDecl(Constructor, Loc); + + TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo(); + if (!TSInfo) + TSInfo = S.Context.getTrivialTypeSourceInfo(Entity.getType(), Loc); + SourceRange ParenRange; + if (Kind.getKind() != InitializationKind::IK_DirectList) + ParenRange = Kind.getParenRange(); + + CurInit = S.Owned(new (S.Context) CXXTemporaryObjectExpr(S.Context, + Constructor, + TSInfo, + Exprs, + NumExprs, + ParenRange, + HadMultipleCandidates, + ConstructorInitRequiresZeroInit)); + } else { + CXXConstructExpr::ConstructionKind ConstructKind = + CXXConstructExpr::CK_Complete; + + if (Entity.getKind() == InitializedEntity::EK_Base) { + ConstructKind = Entity.getBaseSpecifier()->isVirtual() ? + CXXConstructExpr::CK_VirtualBase : + CXXConstructExpr::CK_NonVirtualBase; + } else if (Entity.getKind() == InitializedEntity::EK_Delegating) { + ConstructKind = CXXConstructExpr::CK_Delegating; + } + + // Only get the parenthesis range if it is a direct construction. + SourceRange parenRange = + Kind.getKind() == InitializationKind::IK_Direct ? + Kind.getParenRange() : SourceRange(); + + // If the entity allows NRVO, mark the construction as elidable + // unconditionally. + if (Entity.allowsNRVO()) + CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(), + Constructor, /*Elidable=*/true, + move_arg(ConstructorArgs), + HadMultipleCandidates, + ConstructorInitRequiresZeroInit, + ConstructKind, + parenRange); + else + CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(), + Constructor, + move_arg(ConstructorArgs), + HadMultipleCandidates, + ConstructorInitRequiresZeroInit, + ConstructKind, + parenRange); + } + if (CurInit.isInvalid()) + return ExprError(); + + // Only check access if all of that succeeded. + S.CheckConstructorAccess(Loc, Constructor, Entity, + Step.Function.FoundDecl.getAccess()); + S.DiagnoseUseOfDecl(Step.Function.FoundDecl, Loc); + + if (shouldBindAsTemporary(Entity)) + CurInit = S.MaybeBindToTemporary(CurInit.takeAs()); + + return move(CurInit); +} + +ExprResult +InitializationSequence::Perform(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + MultiExprArg Args, + QualType *ResultType) { + if (Failed()) { + unsigned NumArgs = Args.size(); + Diagnose(S, Entity, Kind, (Expr **)Args.release(), NumArgs); + return ExprError(); + } + + if (getKind() == DependentSequence) { + // If the declaration is a non-dependent, incomplete array type + // that has an initializer, then its type will be completed once + // the initializer is instantiated. + if (ResultType && !Entity.getType()->isDependentType() && + Args.size() == 1) { + QualType DeclType = Entity.getType(); + if (const IncompleteArrayType *ArrayT + = S.Context.getAsIncompleteArrayType(DeclType)) { + // FIXME: We don't currently have the ability to accurately + // compute the length of an initializer list without + // performing full type-checking of the initializer list + // (since we have to determine where braces are implicitly + // introduced and such). So, we fall back to making the array + // type a dependently-sized array type with no specified + // bound. + if (isa((Expr *)Args.get()[0])) { + SourceRange Brackets; + + // Scavange the location of the brackets from the entity, if we can. + if (DeclaratorDecl *DD = Entity.getDecl()) { + if (TypeSourceInfo *TInfo = DD->getTypeSourceInfo()) { + TypeLoc TL = TInfo->getTypeLoc(); + if (IncompleteArrayTypeLoc *ArrayLoc + = dyn_cast(&TL)) + Brackets = ArrayLoc->getBracketsRange(); + } + } + + *ResultType + = S.Context.getDependentSizedArrayType(ArrayT->getElementType(), + /*NumElts=*/0, + ArrayT->getSizeModifier(), + ArrayT->getIndexTypeCVRQualifiers(), + Brackets); + } + + } + } + if (Kind.getKind() == InitializationKind::IK_Direct && + !Kind.isExplicitCast()) { + // Rebuild the ParenListExpr. + SourceRange ParenRange = Kind.getParenRange(); + return S.ActOnParenListExpr(ParenRange.getBegin(), ParenRange.getEnd(), + move(Args)); + } + assert(Kind.getKind() == InitializationKind::IK_Copy || + Kind.isExplicitCast() || + Kind.getKind() == InitializationKind::IK_DirectList); + return ExprResult(Args.release()[0]); + } + + // No steps means no initialization. + if (Steps.empty()) + return S.Owned((Expr *)0); + + QualType DestType = Entity.getType().getNonReferenceType(); + // FIXME: Ugly hack around the fact that Entity.getType() is not + // the same as Entity.getDecl()->getType() in cases involving type merging, + // and we want latter when it makes sense. + if (ResultType) + *ResultType = Entity.getDecl() ? Entity.getDecl()->getType() : + Entity.getType(); + + ExprResult CurInit = S.Owned((Expr *)0); + + // For initialization steps that start with a single initializer, + // grab the only argument out the Args and place it into the "current" + // initializer. + switch (Steps.front().Kind) { + case SK_ResolveAddressOfOverloadedFunction: + case SK_CastDerivedToBaseRValue: + case SK_CastDerivedToBaseXValue: + case SK_CastDerivedToBaseLValue: + case SK_BindReference: + case SK_BindReferenceToTemporary: + case SK_ExtraneousCopyToTemporary: + case SK_UserConversion: + case SK_QualificationConversionLValue: + case SK_QualificationConversionXValue: + case SK_QualificationConversionRValue: + case SK_ConversionSequence: + case SK_ListConstructorCall: + case SK_ListInitialization: + case SK_UnwrapInitList: + case SK_RewrapInitList: + case SK_CAssignment: + case SK_StringInit: + case SK_ObjCObjectConversion: + case SK_ArrayInit: + case SK_ParenthesizedArrayInit: + case SK_PassByIndirectCopyRestore: + case SK_PassByIndirectRestore: + case SK_ProduceObjCObject: + case SK_StdInitializerList: { + assert(Args.size() == 1); + CurInit = Args.get()[0]; + if (!CurInit.get()) return ExprError(); + break; + } + + case SK_ConstructorInitialization: + case SK_ZeroInitialization: + break; + } + + // Walk through the computed steps for the initialization sequence, + // performing the specified conversions along the way. + bool ConstructorInitRequiresZeroInit = false; + for (step_iterator Step = step_begin(), StepEnd = step_end(); + Step != StepEnd; ++Step) { + if (CurInit.isInvalid()) + return ExprError(); + + QualType SourceType = CurInit.get() ? CurInit.get()->getType() : QualType(); + + switch (Step->Kind) { + case SK_ResolveAddressOfOverloadedFunction: + // Overload resolution determined which function invoke; update the + // initializer to reflect that choice. + S.CheckAddressOfMemberAccess(CurInit.get(), Step->Function.FoundDecl); + S.DiagnoseUseOfDecl(Step->Function.FoundDecl, Kind.getLocation()); + CurInit = S.FixOverloadedFunctionReference(move(CurInit), + Step->Function.FoundDecl, + Step->Function.Function); + break; + + case SK_CastDerivedToBaseRValue: + case SK_CastDerivedToBaseXValue: + case SK_CastDerivedToBaseLValue: { + // We have a derived-to-base cast that produces either an rvalue or an + // lvalue. Perform that cast. + + CXXCastPath BasePath; + + // Casts to inaccessible base classes are allowed with C-style casts. + bool IgnoreBaseAccess = Kind.isCStyleOrFunctionalCast(); + if (S.CheckDerivedToBaseConversion(SourceType, Step->Type, + CurInit.get()->getLocStart(), + CurInit.get()->getSourceRange(), + &BasePath, IgnoreBaseAccess)) + return ExprError(); + + if (S.BasePathInvolvesVirtualBase(BasePath)) { + QualType T = SourceType; + if (const PointerType *Pointer = T->getAs()) + T = Pointer->getPointeeType(); + if (const RecordType *RecordTy = T->getAs()) + S.MarkVTableUsed(CurInit.get()->getLocStart(), + cast(RecordTy->getDecl())); + } + + ExprValueKind VK = + Step->Kind == SK_CastDerivedToBaseLValue ? + VK_LValue : + (Step->Kind == SK_CastDerivedToBaseXValue ? + VK_XValue : + VK_RValue); + CurInit = S.Owned(ImplicitCastExpr::Create(S.Context, + Step->Type, + CK_DerivedToBase, + CurInit.get(), + &BasePath, VK)); + break; + } + + case SK_BindReference: + if (FieldDecl *BitField = CurInit.get()->getBitField()) { + // References cannot bind to bit fields (C++ [dcl.init.ref]p5). + S.Diag(Kind.getLocation(), diag::err_reference_bind_to_bitfield) + << Entity.getType().isVolatileQualified() + << BitField->getDeclName() + << CurInit.get()->getSourceRange(); + S.Diag(BitField->getLocation(), diag::note_bitfield_decl); + return ExprError(); + } + + if (CurInit.get()->refersToVectorElement()) { + // References cannot bind to vector elements. + S.Diag(Kind.getLocation(), diag::err_reference_bind_to_vector_element) + << Entity.getType().isVolatileQualified() + << CurInit.get()->getSourceRange(); + PrintInitLocationNote(S, Entity); + return ExprError(); + } + + // Reference binding does not have any corresponding ASTs. + + // Check exception specifications + if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType)) + return ExprError(); + + break; + + case SK_BindReferenceToTemporary: + // Check exception specifications + if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType)) + return ExprError(); + + // Materialize the temporary into memory. + CurInit = new (S.Context) MaterializeTemporaryExpr( + Entity.getType().getNonReferenceType(), + CurInit.get(), + Entity.getType()->isLValueReferenceType()); + + // If we're binding to an Objective-C object that has lifetime, we + // need cleanups. + if (S.getLangOpts().ObjCAutoRefCount && + CurInit.get()->getType()->isObjCLifetimeType()) + S.ExprNeedsCleanups = true; + + break; + + case SK_ExtraneousCopyToTemporary: + CurInit = CopyObject(S, Step->Type, Entity, move(CurInit), + /*IsExtraneousCopy=*/true); + break; + + case SK_UserConversion: { + // We have a user-defined conversion that invokes either a constructor + // or a conversion function. + CastKind CastKind; + bool IsCopy = false; + FunctionDecl *Fn = Step->Function.Function; + DeclAccessPair FoundFn = Step->Function.FoundDecl; + bool HadMultipleCandidates = Step->Function.HadMultipleCandidates; + bool CreatedObject = false; + if (CXXConstructorDecl *Constructor = dyn_cast(Fn)) { + // Build a call to the selected constructor. + ASTOwningVector ConstructorArgs(S); + SourceLocation Loc = CurInit.get()->getLocStart(); + CurInit.release(); // Ownership transferred into MultiExprArg, below. + + // Determine the arguments required to actually perform the constructor + // call. + Expr *Arg = CurInit.get(); + if (S.CompleteConstructorCall(Constructor, + MultiExprArg(&Arg, 1), + Loc, ConstructorArgs)) + return ExprError(); + + // Build an expression that constructs a temporary. + CurInit = S.BuildCXXConstructExpr(Loc, Step->Type, Constructor, + move_arg(ConstructorArgs), + HadMultipleCandidates, + /*ZeroInit*/ false, + CXXConstructExpr::CK_Complete, + SourceRange()); + if (CurInit.isInvalid()) + return ExprError(); + + S.CheckConstructorAccess(Kind.getLocation(), Constructor, Entity, + FoundFn.getAccess()); + S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()); + + CastKind = CK_ConstructorConversion; + QualType Class = S.Context.getTypeDeclType(Constructor->getParent()); + if (S.Context.hasSameUnqualifiedType(SourceType, Class) || + S.IsDerivedFrom(SourceType, Class)) + IsCopy = true; + + CreatedObject = true; + } else { + // Build a call to the conversion function. + CXXConversionDecl *Conversion = cast(Fn); + S.CheckMemberOperatorAccess(Kind.getLocation(), CurInit.get(), 0, + FoundFn); + S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation()); + + // FIXME: Should we move this initialization into a separate + // derived-to-base conversion? I believe the answer is "no", because + // we don't want to turn off access control here for c-style casts. + ExprResult CurInitExprRes = + S.PerformObjectArgumentInitialization(CurInit.take(), /*Qualifier=*/0, + FoundFn, Conversion); + if(CurInitExprRes.isInvalid()) + return ExprError(); + CurInit = move(CurInitExprRes); + + // Build the actual call to the conversion function. + CurInit = S.BuildCXXMemberCallExpr(CurInit.get(), FoundFn, Conversion, + HadMultipleCandidates); + if (CurInit.isInvalid() || !CurInit.get()) + return ExprError(); + + CastKind = CK_UserDefinedConversion; + + CreatedObject = Conversion->getResultType()->isRecordType(); + } + + bool RequiresCopy = !IsCopy && !isReferenceBinding(Steps.back()); + bool MaybeBindToTemp = RequiresCopy || shouldBindAsTemporary(Entity); + + if (!MaybeBindToTemp && CreatedObject && shouldDestroyTemporary(Entity)) { + QualType T = CurInit.get()->getType(); + if (const RecordType *Record = T->getAs()) { + CXXDestructorDecl *Destructor + = S.LookupDestructor(cast(Record->getDecl())); + S.CheckDestructorAccess(CurInit.get()->getLocStart(), Destructor, + S.PDiag(diag::err_access_dtor_temp) << T); + S.MarkFunctionReferenced(CurInit.get()->getLocStart(), Destructor); + S.DiagnoseUseOfDecl(Destructor, CurInit.get()->getLocStart()); + } + } + + CurInit = S.Owned(ImplicitCastExpr::Create(S.Context, + CurInit.get()->getType(), + CastKind, CurInit.get(), 0, + CurInit.get()->getValueKind())); + if (MaybeBindToTemp) + CurInit = S.MaybeBindToTemporary(CurInit.takeAs()); + if (RequiresCopy) + CurInit = CopyObject(S, Entity.getType().getNonReferenceType(), Entity, + move(CurInit), /*IsExtraneousCopy=*/false); + break; + } + + case SK_QualificationConversionLValue: + case SK_QualificationConversionXValue: + case SK_QualificationConversionRValue: { + // Perform a qualification conversion; these can never go wrong. + ExprValueKind VK = + Step->Kind == SK_QualificationConversionLValue ? + VK_LValue : + (Step->Kind == SK_QualificationConversionXValue ? + VK_XValue : + VK_RValue); + CurInit = S.ImpCastExprToType(CurInit.take(), Step->Type, CK_NoOp, VK); + break; + } + + case SK_ConversionSequence: { + Sema::CheckedConversionKind CCK + = Kind.isCStyleCast()? Sema::CCK_CStyleCast + : Kind.isFunctionalCast()? Sema::CCK_FunctionalCast + : Kind.isExplicitCast()? Sema::CCK_OtherCast + : Sema::CCK_ImplicitConversion; + ExprResult CurInitExprRes = + S.PerformImplicitConversion(CurInit.get(), Step->Type, *Step->ICS, + getAssignmentAction(Entity), CCK); + if (CurInitExprRes.isInvalid()) + return ExprError(); + CurInit = move(CurInitExprRes); + break; + } + + case SK_ListInitialization: { + InitListExpr *InitList = cast(CurInit.get()); + // Hack: We must pass *ResultType if available in order to set the type + // of arrays, e.g. in 'int ar[] = {1, 2, 3};'. + // But in 'const X &x = {1, 2, 3};' we're supposed to initialize a + // temporary, not a reference, so we should pass Ty. + // Worst case: 'const int (&arref)[] = {1, 2, 3};'. + // Since this step is never used for a reference directly, we explicitly + // unwrap references here and rewrap them afterwards. + // We also need to create a InitializeTemporary entity for this. + QualType Ty = ResultType ? ResultType->getNonReferenceType() : Step->Type; + bool IsTemporary = Entity.getType()->isReferenceType(); + InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(Ty); + InitListChecker PerformInitList(S, IsTemporary ? TempEntity : Entity, + InitList, Ty, /*VerifyOnly=*/false, + Kind.getKind() != InitializationKind::IK_DirectList || + !S.getLangOpts().CPlusPlus0x); + if (PerformInitList.HadError()) + return ExprError(); + + if (ResultType) { + if ((*ResultType)->isRValueReferenceType()) + Ty = S.Context.getRValueReferenceType(Ty); + else if ((*ResultType)->isLValueReferenceType()) + Ty = S.Context.getLValueReferenceType(Ty, + (*ResultType)->getAs()->isSpelledAsLValue()); + *ResultType = Ty; + } + + InitListExpr *StructuredInitList = + PerformInitList.getFullyStructuredList(); + CurInit.release(); + CurInit = S.Owned(StructuredInitList); + break; + } + + case SK_ListConstructorCall: { + // When an initializer list is passed for a parameter of type "reference + // to object", we don't get an EK_Temporary entity, but instead an + // EK_Parameter entity with reference type. + // FIXME: This is a hack. What we really should do is create a user + // conversion step for this case, but this makes it considerably more + // complicated. For now, this will do. + InitializedEntity TempEntity = InitializedEntity::InitializeTemporary( + Entity.getType().getNonReferenceType()); + bool UseTemporary = Entity.getType()->isReferenceType(); + InitListExpr *InitList = cast(CurInit.get()); + MultiExprArg Arg(InitList->getInits(), InitList->getNumInits()); + CurInit = PerformConstructorInitialization(S, UseTemporary ? TempEntity : + Entity, + Kind, move(Arg), *Step, + ConstructorInitRequiresZeroInit); + break; + } + + case SK_UnwrapInitList: + CurInit = S.Owned(cast(CurInit.take())->getInit(0)); + break; + + case SK_RewrapInitList: { + Expr *E = CurInit.take(); + InitListExpr *Syntactic = Step->WrappingSyntacticList; + InitListExpr *ILE = new (S.Context) InitListExpr(S.Context, + Syntactic->getLBraceLoc(), &E, 1, Syntactic->getRBraceLoc()); + ILE->setSyntacticForm(Syntactic); + ILE->setType(E->getType()); + ILE->setValueKind(E->getValueKind()); + CurInit = S.Owned(ILE); + break; + } + + case SK_ConstructorInitialization: { + // When an initializer list is passed for a parameter of type "reference + // to object", we don't get an EK_Temporary entity, but instead an + // EK_Parameter entity with reference type. + // FIXME: This is a hack. What we really should do is create a user + // conversion step for this case, but this makes it considerably more + // complicated. For now, this will do. + InitializedEntity TempEntity = InitializedEntity::InitializeTemporary( + Entity.getType().getNonReferenceType()); + bool UseTemporary = Entity.getType()->isReferenceType(); + CurInit = PerformConstructorInitialization(S, UseTemporary ? TempEntity + : Entity, + Kind, move(Args), *Step, + ConstructorInitRequiresZeroInit); + break; + } + + case SK_ZeroInitialization: { + step_iterator NextStep = Step; + ++NextStep; + if (NextStep != StepEnd && + NextStep->Kind == SK_ConstructorInitialization) { + // The need for zero-initialization is recorded directly into + // the call to the object's constructor within the next step. + ConstructorInitRequiresZeroInit = true; + } else if (Kind.getKind() == InitializationKind::IK_Value && + S.getLangOpts().CPlusPlus && + !Kind.isImplicitValueInit()) { + TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo(); + if (!TSInfo) + TSInfo = S.Context.getTrivialTypeSourceInfo(Step->Type, + Kind.getRange().getBegin()); + + CurInit = S.Owned(new (S.Context) CXXScalarValueInitExpr( + TSInfo->getType().getNonLValueExprType(S.Context), + TSInfo, + Kind.getRange().getEnd())); + } else { + CurInit = S.Owned(new (S.Context) ImplicitValueInitExpr(Step->Type)); + } + break; + } + + case SK_CAssignment: { + QualType SourceType = CurInit.get()->getType(); + ExprResult Result = move(CurInit); + Sema::AssignConvertType ConvTy = + S.CheckSingleAssignmentConstraints(Step->Type, Result); + if (Result.isInvalid()) + return ExprError(); + CurInit = move(Result); + + // If this is a call, allow conversion to a transparent union. + ExprResult CurInitExprRes = move(CurInit); + if (ConvTy != Sema::Compatible && + Entity.getKind() == InitializedEntity::EK_Parameter && + S.CheckTransparentUnionArgumentConstraints(Step->Type, CurInitExprRes) + == Sema::Compatible) + ConvTy = Sema::Compatible; + if (CurInitExprRes.isInvalid()) + return ExprError(); + CurInit = move(CurInitExprRes); + + bool Complained; + if (S.DiagnoseAssignmentResult(ConvTy, Kind.getLocation(), + Step->Type, SourceType, + CurInit.get(), + getAssignmentAction(Entity), + &Complained)) { + PrintInitLocationNote(S, Entity); + return ExprError(); + } else if (Complained) + PrintInitLocationNote(S, Entity); + break; + } + + case SK_StringInit: { + QualType Ty = Step->Type; + CheckStringInit(CurInit.get(), ResultType ? *ResultType : Ty, + S.Context.getAsArrayType(Ty), S); + break; + } + + case SK_ObjCObjectConversion: + CurInit = S.ImpCastExprToType(CurInit.take(), Step->Type, + CK_ObjCObjectLValueCast, + CurInit.get()->getValueKind()); + break; + + case SK_ArrayInit: + // Okay: we checked everything before creating this step. Note that + // this is a GNU extension. + S.Diag(Kind.getLocation(), diag::ext_array_init_copy) + << Step->Type << CurInit.get()->getType() + << CurInit.get()->getSourceRange(); + + // If the destination type is an incomplete array type, update the + // type accordingly. + if (ResultType) { + if (const IncompleteArrayType *IncompleteDest + = S.Context.getAsIncompleteArrayType(Step->Type)) { + if (const ConstantArrayType *ConstantSource + = S.Context.getAsConstantArrayType(CurInit.get()->getType())) { + *ResultType = S.Context.getConstantArrayType( + IncompleteDest->getElementType(), + ConstantSource->getSize(), + ArrayType::Normal, 0); + } + } + } + break; + + case SK_ParenthesizedArrayInit: + // Okay: we checked everything before creating this step. Note that + // this is a GNU extension. + S.Diag(Kind.getLocation(), diag::ext_array_init_parens) + << CurInit.get()->getSourceRange(); + break; + + case SK_PassByIndirectCopyRestore: + case SK_PassByIndirectRestore: + checkIndirectCopyRestoreSource(S, CurInit.get()); + CurInit = S.Owned(new (S.Context) + ObjCIndirectCopyRestoreExpr(CurInit.take(), Step->Type, + Step->Kind == SK_PassByIndirectCopyRestore)); + break; + + case SK_ProduceObjCObject: + CurInit = S.Owned(ImplicitCastExpr::Create(S.Context, Step->Type, + CK_ARCProduceObject, + CurInit.take(), 0, VK_RValue)); + break; + + case SK_StdInitializerList: { + QualType Dest = Step->Type; + QualType E; + bool Success = S.isStdInitializerList(Dest, &E); + (void)Success; + assert(Success && "Destination type changed?"); + + // If the element type has a destructor, check it. + if (CXXRecordDecl *RD = E->getAsCXXRecordDecl()) { + if (!RD->hasIrrelevantDestructor()) { + if (CXXDestructorDecl *Destructor = S.LookupDestructor(RD)) { + S.MarkFunctionReferenced(Kind.getLocation(), Destructor); + S.CheckDestructorAccess(Kind.getLocation(), Destructor, + S.PDiag(diag::err_access_dtor_temp) << E); + S.DiagnoseUseOfDecl(Destructor, Kind.getLocation()); + } + } + } + + InitListExpr *ILE = cast(CurInit.take()); + unsigned NumInits = ILE->getNumInits(); + SmallVector Converted(NumInits); + InitializedEntity HiddenArray = InitializedEntity::InitializeTemporary( + S.Context.getConstantArrayType(E, + llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()), + NumInits), + ArrayType::Normal, 0)); + InitializedEntity Element =InitializedEntity::InitializeElement(S.Context, + 0, HiddenArray); + for (unsigned i = 0; i < NumInits; ++i) { + Element.setElementIndex(i); + ExprResult Init = S.Owned(ILE->getInit(i)); + ExprResult Res = S.PerformCopyInitialization(Element, + Init.get()->getExprLoc(), + Init); + assert(!Res.isInvalid() && "Result changed since try phase."); + Converted[i] = Res.take(); + } + InitListExpr *Semantic = new (S.Context) + InitListExpr(S.Context, ILE->getLBraceLoc(), + Converted.data(), NumInits, ILE->getRBraceLoc()); + Semantic->setSyntacticForm(ILE); + Semantic->setType(Dest); + Semantic->setInitializesStdInitializerList(); + CurInit = S.Owned(Semantic); + break; + } + } + } + + // Diagnose non-fatal problems with the completed initialization. + if (Entity.getKind() == InitializedEntity::EK_Member && + cast(Entity.getDecl())->isBitField()) + S.CheckBitFieldInitialization(Kind.getLocation(), + cast(Entity.getDecl()), + CurInit.get()); + + return move(CurInit); +} + +//===----------------------------------------------------------------------===// +// Diagnose initialization failures +//===----------------------------------------------------------------------===// +bool InitializationSequence::Diagnose(Sema &S, + const InitializedEntity &Entity, + const InitializationKind &Kind, + Expr **Args, unsigned NumArgs) { + if (!Failed()) + return false; + + QualType DestType = Entity.getType(); + switch (Failure) { + case FK_TooManyInitsForReference: + // FIXME: Customize for the initialized entity? + if (NumArgs == 0) + S.Diag(Kind.getLocation(), diag::err_reference_without_init) + << DestType.getNonReferenceType(); + else // FIXME: diagnostic below could be better! + S.Diag(Kind.getLocation(), diag::err_reference_has_multiple_inits) + << SourceRange(Args[0]->getLocStart(), Args[NumArgs - 1]->getLocEnd()); + break; + + case FK_ArrayNeedsInitList: + case FK_ArrayNeedsInitListOrStringLiteral: + S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) + << (Failure == FK_ArrayNeedsInitListOrStringLiteral); + break; + + case FK_ArrayTypeMismatch: + case FK_NonConstantArrayInit: + S.Diag(Kind.getLocation(), + (Failure == FK_ArrayTypeMismatch + ? diag::err_array_init_different_type + : diag::err_array_init_non_constant_array)) + << DestType.getNonReferenceType() + << Args[0]->getType() + << Args[0]->getSourceRange(); + break; + + case FK_VariableLengthArrayHasInitializer: + S.Diag(Kind.getLocation(), diag::err_variable_object_no_init) + << Args[0]->getSourceRange(); + break; + + case FK_AddressOfOverloadFailed: { + DeclAccessPair Found; + S.ResolveAddressOfOverloadedFunction(Args[0], + DestType.getNonReferenceType(), + true, + Found); + break; + } + + case FK_ReferenceInitOverloadFailed: + case FK_UserConversionOverloadFailed: + switch (FailedOverloadResult) { + case OR_Ambiguous: + if (Failure == FK_UserConversionOverloadFailed) + S.Diag(Kind.getLocation(), diag::err_typecheck_ambiguous_condition) + << Args[0]->getType() << DestType + << Args[0]->getSourceRange(); + else + S.Diag(Kind.getLocation(), diag::err_ref_init_ambiguous) + << DestType << Args[0]->getType() + << Args[0]->getSourceRange(); + + FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, + llvm::makeArrayRef(Args, NumArgs)); + break; + + case OR_No_Viable_Function: + S.Diag(Kind.getLocation(), diag::err_typecheck_nonviable_condition) + << Args[0]->getType() << DestType.getNonReferenceType() + << Args[0]->getSourceRange(); + FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, + llvm::makeArrayRef(Args, NumArgs)); + break; + + case OR_Deleted: { + S.Diag(Kind.getLocation(), diag::err_typecheck_deleted_function) + << Args[0]->getType() << DestType.getNonReferenceType() + << Args[0]->getSourceRange(); + OverloadCandidateSet::iterator Best; + OverloadingResult Ovl + = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best, + true); + if (Ovl == OR_Deleted) { + S.NoteDeletedFunction(Best->Function); + } else { + llvm_unreachable("Inconsistent overload resolution?"); + } + break; + } + + case OR_Success: + llvm_unreachable("Conversion did not fail!"); + } + break; + + case FK_NonConstLValueReferenceBindingToTemporary: + if (isa(Args[0])) { + S.Diag(Kind.getLocation(), + diag::err_lvalue_reference_bind_to_initlist) + << DestType.getNonReferenceType().isVolatileQualified() + << DestType.getNonReferenceType() + << Args[0]->getSourceRange(); + break; + } + // Intentional fallthrough + + case FK_NonConstLValueReferenceBindingToUnrelated: + S.Diag(Kind.getLocation(), + Failure == FK_NonConstLValueReferenceBindingToTemporary + ? diag::err_lvalue_reference_bind_to_temporary + : diag::err_lvalue_reference_bind_to_unrelated) + << DestType.getNonReferenceType().isVolatileQualified() + << DestType.getNonReferenceType() + << Args[0]->getType() + << Args[0]->getSourceRange(); + break; + + case FK_RValueReferenceBindingToLValue: + S.Diag(Kind.getLocation(), diag::err_lvalue_to_rvalue_ref) + << DestType.getNonReferenceType() << Args[0]->getType() + << Args[0]->getSourceRange(); + break; + + case FK_ReferenceInitDropsQualifiers: + S.Diag(Kind.getLocation(), diag::err_reference_bind_drops_quals) + << DestType.getNonReferenceType() + << Args[0]->getType() + << Args[0]->getSourceRange(); + break; + + case FK_ReferenceInitFailed: + S.Diag(Kind.getLocation(), diag::err_reference_bind_failed) + << DestType.getNonReferenceType() + << Args[0]->isLValue() + << Args[0]->getType() + << Args[0]->getSourceRange(); + if (DestType.getNonReferenceType()->isObjCObjectPointerType() && + Args[0]->getType()->isObjCObjectPointerType()) + S.EmitRelatedResultTypeNote(Args[0]); + break; + + case FK_ConversionFailed: { + QualType FromType = Args[0]->getType(); + PartialDiagnostic PDiag = S.PDiag(diag::err_init_conversion_failed) + << (int)Entity.getKind() + << DestType + << Args[0]->isLValue() + << FromType + << Args[0]->getSourceRange(); + S.HandleFunctionTypeMismatch(PDiag, FromType, DestType); + S.Diag(Kind.getLocation(), PDiag); + if (DestType.getNonReferenceType()->isObjCObjectPointerType() && + Args[0]->getType()->isObjCObjectPointerType()) + S.EmitRelatedResultTypeNote(Args[0]); + break; + } + + case FK_ConversionFromPropertyFailed: + // No-op. This error has already been reported. + break; + + case FK_TooManyInitsForScalar: { + SourceRange R; + + if (InitListExpr *InitList = dyn_cast(Args[0])) + R = SourceRange(InitList->getInit(0)->getLocEnd(), + InitList->getLocEnd()); + else + R = SourceRange(Args[0]->getLocEnd(), Args[NumArgs - 1]->getLocEnd()); + + R.setBegin(S.PP.getLocForEndOfToken(R.getBegin())); + if (Kind.isCStyleOrFunctionalCast()) + S.Diag(Kind.getLocation(), diag::err_builtin_func_cast_more_than_one_arg) + << R; + else + S.Diag(Kind.getLocation(), diag::err_excess_initializers) + << /*scalar=*/2 << R; + break; + } + + case FK_ReferenceBindingToInitList: + S.Diag(Kind.getLocation(), diag::err_reference_bind_init_list) + << DestType.getNonReferenceType() << Args[0]->getSourceRange(); + break; + + case FK_InitListBadDestinationType: + S.Diag(Kind.getLocation(), diag::err_init_list_bad_dest_type) + << (DestType->isRecordType()) << DestType << Args[0]->getSourceRange(); + break; + + case FK_ListConstructorOverloadFailed: + case FK_ConstructorOverloadFailed: { + SourceRange ArgsRange; + if (NumArgs) + ArgsRange = SourceRange(Args[0]->getLocStart(), + Args[NumArgs - 1]->getLocEnd()); + + if (Failure == FK_ListConstructorOverloadFailed) { + assert(NumArgs == 1 && "List construction from other than 1 argument."); + InitListExpr *InitList = cast(Args[0]); + Args = InitList->getInits(); + NumArgs = InitList->getNumInits(); + } + + // FIXME: Using "DestType" for the entity we're printing is probably + // bad. + switch (FailedOverloadResult) { + case OR_Ambiguous: + S.Diag(Kind.getLocation(), diag::err_ovl_ambiguous_init) + << DestType << ArgsRange; + FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, + llvm::makeArrayRef(Args, NumArgs)); + break; + + case OR_No_Viable_Function: + if (Kind.getKind() == InitializationKind::IK_Default && + (Entity.getKind() == InitializedEntity::EK_Base || + Entity.getKind() == InitializedEntity::EK_Member) && + isa(S.CurContext)) { + // This is implicit default initialization of a member or + // base within a constructor. If no viable function was + // found, notify the user that she needs to explicitly + // initialize this base/member. + CXXConstructorDecl *Constructor + = cast(S.CurContext); + if (Entity.getKind() == InitializedEntity::EK_Base) { + S.Diag(Kind.getLocation(), diag::err_missing_default_ctor) + << Constructor->isImplicit() + << S.Context.getTypeDeclType(Constructor->getParent()) + << /*base=*/0 + << Entity.getType(); + + RecordDecl *BaseDecl + = Entity.getBaseSpecifier()->getType()->getAs() + ->getDecl(); + S.Diag(BaseDecl->getLocation(), diag::note_previous_decl) + << S.Context.getTagDeclType(BaseDecl); + } else { + S.Diag(Kind.getLocation(), diag::err_missing_default_ctor) + << Constructor->isImplicit() + << S.Context.getTypeDeclType(Constructor->getParent()) + << /*member=*/1 + << Entity.getName(); + S.Diag(Entity.getDecl()->getLocation(), diag::note_field_decl); + + if (const RecordType *Record + = Entity.getType()->getAs()) + S.Diag(Record->getDecl()->getLocation(), + diag::note_previous_decl) + << S.Context.getTagDeclType(Record->getDecl()); + } + break; + } + + S.Diag(Kind.getLocation(), diag::err_ovl_no_viable_function_in_init) + << DestType << ArgsRange; + FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, + llvm::makeArrayRef(Args, NumArgs)); + break; + + case OR_Deleted: { + OverloadCandidateSet::iterator Best; + OverloadingResult Ovl + = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best); + if (Ovl != OR_Deleted) { + S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init) + << true << DestType << ArgsRange; + llvm_unreachable("Inconsistent overload resolution?"); + break; + } + + // If this is a defaulted or implicitly-declared function, then + // it was implicitly deleted. Make it clear that the deletion was + // implicit. + if (S.isImplicitlyDeleted(Best->Function)) + S.Diag(Kind.getLocation(), diag::err_ovl_deleted_special_init) + << S.getSpecialMember(cast(Best->Function)) + << DestType << ArgsRange; + else + S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init) + << true << DestType << ArgsRange; + + S.NoteDeletedFunction(Best->Function); + break; + } + + case OR_Success: + llvm_unreachable("Conversion did not fail!"); + } + } + break; + + case FK_DefaultInitOfConst: + if (Entity.getKind() == InitializedEntity::EK_Member && + isa(S.CurContext)) { + // This is implicit default-initialization of a const member in + // a constructor. Complain that it needs to be explicitly + // initialized. + CXXConstructorDecl *Constructor = cast(S.CurContext); + S.Diag(Kind.getLocation(), diag::err_uninitialized_member_in_ctor) + << Constructor->isImplicit() + << S.Context.getTypeDeclType(Constructor->getParent()) + << /*const=*/1 + << Entity.getName(); + S.Diag(Entity.getDecl()->getLocation(), diag::note_previous_decl) + << Entity.getName(); + } else { + S.Diag(Kind.getLocation(), diag::err_default_init_const) + << DestType << (bool)DestType->getAs(); + } + break; + + case FK_Incomplete: + S.RequireCompleteType(Kind.getLocation(), FailedIncompleteType, + diag::err_init_incomplete_type); + break; + + case FK_ListInitializationFailed: { + // Run the init list checker again to emit diagnostics. + InitListExpr* InitList = cast(Args[0]); + QualType DestType = Entity.getType(); + InitListChecker DiagnoseInitList(S, Entity, InitList, + DestType, /*VerifyOnly=*/false, + Kind.getKind() != InitializationKind::IK_DirectList || + !S.getLangOpts().CPlusPlus0x); + assert(DiagnoseInitList.HadError() && + "Inconsistent init list check result."); + break; + } + + case FK_PlaceholderType: { + // FIXME: Already diagnosed! + break; + } + + case FK_InitListElementCopyFailure: { + // Try to perform all copies again. + InitListExpr* InitList = cast(Args[0]); + unsigned NumInits = InitList->getNumInits(); + QualType DestType = Entity.getType(); + QualType E; + bool Success = S.isStdInitializerList(DestType, &E); + (void)Success; + assert(Success && "Where did the std::initializer_list go?"); + InitializedEntity HiddenArray = InitializedEntity::InitializeTemporary( + S.Context.getConstantArrayType(E, + llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()), + NumInits), + ArrayType::Normal, 0)); + InitializedEntity Element = InitializedEntity::InitializeElement(S.Context, + 0, HiddenArray); + // Show at most 3 errors. Otherwise, you'd get a lot of errors for errors + // where the init list type is wrong, e.g. + // std::initializer_list list = { 1, 2, 3, 4, 5, 6, 7, 8 }; + // FIXME: Emit a note if we hit the limit? + int ErrorCount = 0; + for (unsigned i = 0; i < NumInits && ErrorCount < 3; ++i) { + Element.setElementIndex(i); + ExprResult Init = S.Owned(InitList->getInit(i)); + if (S.PerformCopyInitialization(Element, Init.get()->getExprLoc(), Init) + .isInvalid()) + ++ErrorCount; + } + break; + } + + case FK_ExplicitConstructor: { + S.Diag(Kind.getLocation(), diag::err_selected_explicit_constructor) + << Args[0]->getSourceRange(); + OverloadCandidateSet::iterator Best; + OverloadingResult Ovl + = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best); + (void)Ovl; + assert(Ovl == OR_Success && "Inconsistent overload resolution"); + CXXConstructorDecl *CtorDecl = cast(Best->Function); + S.Diag(CtorDecl->getLocation(), diag::note_constructor_declared_here); + break; + } + } + + PrintInitLocationNote(S, Entity); + return true; +} + +void InitializationSequence::dump(raw_ostream &OS) const { + switch (SequenceKind) { + case FailedSequence: { + OS << "Failed sequence: "; + switch (Failure) { + case FK_TooManyInitsForReference: + OS << "too many initializers for reference"; + break; + + case FK_ArrayNeedsInitList: + OS << "array requires initializer list"; + break; + + case FK_ArrayNeedsInitListOrStringLiteral: + OS << "array requires initializer list or string literal"; + break; + + case FK_ArrayTypeMismatch: + OS << "array type mismatch"; + break; + + case FK_NonConstantArrayInit: + OS << "non-constant array initializer"; + break; + + case FK_AddressOfOverloadFailed: + OS << "address of overloaded function failed"; + break; + + case FK_ReferenceInitOverloadFailed: + OS << "overload resolution for reference initialization failed"; + break; + + case FK_NonConstLValueReferenceBindingToTemporary: + OS << "non-const lvalue reference bound to temporary"; + break; + + case FK_NonConstLValueReferenceBindingToUnrelated: + OS << "non-const lvalue reference bound to unrelated type"; + break; + + case FK_RValueReferenceBindingToLValue: + OS << "rvalue reference bound to an lvalue"; + break; + + case FK_ReferenceInitDropsQualifiers: + OS << "reference initialization drops qualifiers"; + break; + + case FK_ReferenceInitFailed: + OS << "reference initialization failed"; + break; + + case FK_ConversionFailed: + OS << "conversion failed"; + break; + + case FK_ConversionFromPropertyFailed: + OS << "conversion from property failed"; + break; + + case FK_TooManyInitsForScalar: + OS << "too many initializers for scalar"; + break; + + case FK_ReferenceBindingToInitList: + OS << "referencing binding to initializer list"; + break; + + case FK_InitListBadDestinationType: + OS << "initializer list for non-aggregate, non-scalar type"; + break; + + case FK_UserConversionOverloadFailed: + OS << "overloading failed for user-defined conversion"; + break; + + case FK_ConstructorOverloadFailed: + OS << "constructor overloading failed"; + break; + + case FK_DefaultInitOfConst: + OS << "default initialization of a const variable"; + break; + + case FK_Incomplete: + OS << "initialization of incomplete type"; + break; + + case FK_ListInitializationFailed: + OS << "list initialization checker failure"; + break; + + case FK_VariableLengthArrayHasInitializer: + OS << "variable length array has an initializer"; + break; + + case FK_PlaceholderType: + OS << "initializer expression isn't contextually valid"; + break; + + case FK_ListConstructorOverloadFailed: + OS << "list constructor overloading failed"; + break; + + case FK_InitListElementCopyFailure: + OS << "copy construction of initializer list element failed"; + break; + + case FK_ExplicitConstructor: + OS << "list copy initialization chose explicit constructor"; + break; + } + OS << '\n'; + return; + } + + case DependentSequence: + OS << "Dependent sequence\n"; + return; + + case NormalSequence: + OS << "Normal sequence: "; + break; + } + + for (step_iterator S = step_begin(), SEnd = step_end(); S != SEnd; ++S) { + if (S != step_begin()) { + OS << " -> "; + } + + switch (S->Kind) { + case SK_ResolveAddressOfOverloadedFunction: + OS << "resolve address of overloaded function"; + break; + + case SK_CastDerivedToBaseRValue: + OS << "derived-to-base case (rvalue" << S->Type.getAsString() << ")"; + break; + + case SK_CastDerivedToBaseXValue: + OS << "derived-to-base case (xvalue" << S->Type.getAsString() << ")"; + break; + + case SK_CastDerivedToBaseLValue: + OS << "derived-to-base case (lvalue" << S->Type.getAsString() << ")"; + break; + + case SK_BindReference: + OS << "bind reference to lvalue"; + break; + + case SK_BindReferenceToTemporary: + OS << "bind reference to a temporary"; + break; + + case SK_ExtraneousCopyToTemporary: + OS << "extraneous C++03 copy to temporary"; + break; + + case SK_UserConversion: + OS << "user-defined conversion via " << *S->Function.Function; + break; + + case SK_QualificationConversionRValue: + OS << "qualification conversion (rvalue)"; + break; + + case SK_QualificationConversionXValue: + OS << "qualification conversion (xvalue)"; + break; + + case SK_QualificationConversionLValue: + OS << "qualification conversion (lvalue)"; + break; + + case SK_ConversionSequence: + OS << "implicit conversion sequence ("; + S->ICS->DebugPrint(); // FIXME: use OS + OS << ")"; + break; + + case SK_ListInitialization: + OS << "list aggregate initialization"; + break; + + case SK_ListConstructorCall: + OS << "list initialization via constructor"; + break; + + case SK_UnwrapInitList: + OS << "unwrap reference initializer list"; + break; + + case SK_RewrapInitList: + OS << "rewrap reference initializer list"; + break; + + case SK_ConstructorInitialization: + OS << "constructor initialization"; + break; + + case SK_ZeroInitialization: + OS << "zero initialization"; + break; + + case SK_CAssignment: + OS << "C assignment"; + break; + + case SK_StringInit: + OS << "string initialization"; + break; + + case SK_ObjCObjectConversion: + OS << "Objective-C object conversion"; + break; + + case SK_ArrayInit: + OS << "array initialization"; + break; + + case SK_ParenthesizedArrayInit: + OS << "parenthesized array initialization"; + break; + + case SK_PassByIndirectCopyRestore: + OS << "pass by indirect copy and restore"; + break; + + case SK_PassByIndirectRestore: + OS << "pass by indirect restore"; + break; + + case SK_ProduceObjCObject: + OS << "Objective-C object retension"; + break; + + case SK_StdInitializerList: + OS << "std::initializer_list from initializer list"; + break; + } + } +} + +void InitializationSequence::dump() const { + dump(llvm::errs()); +} + +static void DiagnoseNarrowingInInitList(Sema &S, InitializationSequence &Seq, + QualType EntityType, + const Expr *PreInit, + const Expr *PostInit) { + if (Seq.step_begin() == Seq.step_end() || PreInit->isValueDependent()) + return; + + // A narrowing conversion can only appear as the final implicit conversion in + // an initialization sequence. + const InitializationSequence::Step &LastStep = Seq.step_end()[-1]; + if (LastStep.Kind != InitializationSequence::SK_ConversionSequence) + return; + + const ImplicitConversionSequence &ICS = *LastStep.ICS; + const StandardConversionSequence *SCS = 0; + switch (ICS.getKind()) { + case ImplicitConversionSequence::StandardConversion: + SCS = &ICS.Standard; + break; + case ImplicitConversionSequence::UserDefinedConversion: + SCS = &ICS.UserDefined.After; + break; + case ImplicitConversionSequence::AmbiguousConversion: + case ImplicitConversionSequence::EllipsisConversion: + case ImplicitConversionSequence::BadConversion: + return; + } + + // Determine the type prior to the narrowing conversion. If a conversion + // operator was used, this may be different from both the type of the entity + // and of the pre-initialization expression. + QualType PreNarrowingType = PreInit->getType(); + if (Seq.step_begin() + 1 != Seq.step_end()) + PreNarrowingType = Seq.step_end()[-2].Type; + + // C++11 [dcl.init.list]p7: Check whether this is a narrowing conversion. + APValue ConstantValue; + QualType ConstantType; + switch (SCS->getNarrowingKind(S.Context, PostInit, ConstantValue, + ConstantType)) { + case NK_Not_Narrowing: + // No narrowing occurred. + return; + + case NK_Type_Narrowing: + // This was a floating-to-integer conversion, which is always considered a + // narrowing conversion even if the value is a constant and can be + // represented exactly as an integer. + S.Diag(PostInit->getLocStart(), + S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus0x? + diag::warn_init_list_type_narrowing + : S.isSFINAEContext()? + diag::err_init_list_type_narrowing_sfinae + : diag::err_init_list_type_narrowing) + << PostInit->getSourceRange() + << PreNarrowingType.getLocalUnqualifiedType() + << EntityType.getLocalUnqualifiedType(); + break; + + case NK_Constant_Narrowing: + // A constant value was narrowed. + S.Diag(PostInit->getLocStart(), + S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus0x? + diag::warn_init_list_constant_narrowing + : S.isSFINAEContext()? + diag::err_init_list_constant_narrowing_sfinae + : diag::err_init_list_constant_narrowing) + << PostInit->getSourceRange() + << ConstantValue.getAsString(S.getASTContext(), ConstantType) + << EntityType.getLocalUnqualifiedType(); + break; + + case NK_Variable_Narrowing: + // A variable's value may have been narrowed. + S.Diag(PostInit->getLocStart(), + S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus0x? + diag::warn_init_list_variable_narrowing + : S.isSFINAEContext()? + diag::err_init_list_variable_narrowing_sfinae + : diag::err_init_list_variable_narrowing) + << PostInit->getSourceRange() + << PreNarrowingType.getLocalUnqualifiedType() + << EntityType.getLocalUnqualifiedType(); + break; + } + + SmallString<128> StaticCast; + llvm::raw_svector_ostream OS(StaticCast); + OS << "static_cast<"; + if (const TypedefType *TT = EntityType->getAs()) { + // It's important to use the typedef's name if there is one so that the + // fixit doesn't break code using types like int64_t. + // + // FIXME: This will break if the typedef requires qualification. But + // getQualifiedNameAsString() includes non-machine-parsable components. + OS << *TT->getDecl(); + } else if (const BuiltinType *BT = EntityType->getAs()) + OS << BT->getName(S.getLangOpts()); + else { + // Oops, we didn't find the actual type of the variable. Don't emit a fixit + // with a broken cast. + return; + } + OS << ">("; + S.Diag(PostInit->getLocStart(), diag::note_init_list_narrowing_override) + << PostInit->getSourceRange() + << FixItHint::CreateInsertion(PostInit->getLocStart(), OS.str()) + << FixItHint::CreateInsertion( + S.getPreprocessor().getLocForEndOfToken(PostInit->getLocEnd()), ")"); +} + +//===----------------------------------------------------------------------===// +// Initialization helper functions +//===----------------------------------------------------------------------===// +bool +Sema::CanPerformCopyInitialization(const InitializedEntity &Entity, + ExprResult Init) { + if (Init.isInvalid()) + return false; + + Expr *InitE = Init.get(); + assert(InitE && "No initialization expression"); + + InitializationKind Kind = InitializationKind::CreateCopy(SourceLocation(), + SourceLocation()); + InitializationSequence Seq(*this, Entity, Kind, &InitE, 1); + return !Seq.Failed(); +} + +ExprResult +Sema::PerformCopyInitialization(const InitializedEntity &Entity, + SourceLocation EqualLoc, + ExprResult Init, + bool TopLevelOfInitList, + bool AllowExplicit) { + if (Init.isInvalid()) + return ExprError(); + + Expr *InitE = Init.get(); + assert(InitE && "No initialization expression?"); + + if (EqualLoc.isInvalid()) + EqualLoc = InitE->getLocStart(); + + InitializationKind Kind = InitializationKind::CreateCopy(InitE->getLocStart(), + EqualLoc, + AllowExplicit); + InitializationSequence Seq(*this, Entity, Kind, &InitE, 1); + Init.release(); + + ExprResult Result = Seq.Perform(*this, Entity, Kind, MultiExprArg(&InitE, 1)); + + if (!Result.isInvalid() && TopLevelOfInitList) + DiagnoseNarrowingInInitList(*this, Seq, Entity.getType(), + InitE, Result.get()); + + return Result; +} -- cgit v1.2.3