| //===--- 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. The main entry |
| // point is Sema::CheckInitList(), but all of the work is performed |
| // within the InitListChecker class. |
| // |
| // This file also implements Sema::CheckInitializerTypes. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "Sema.h" |
| #include "clang/Parse/Designator.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/AST/ExprObjC.h" |
| #include <map> |
| using namespace clang; |
| |
| //===----------------------------------------------------------------------===// |
| // Sema Initialization Checking |
| //===----------------------------------------------------------------------===// |
| |
| static Expr *IsStringInit(Expr *Init, QualType DeclType, ASTContext &Context) { |
| const ArrayType *AT = Context.getAsArrayType(DeclType); |
| if (!AT) return 0; |
| |
| if (!isa<ConstantArrayType>(AT) && !isa<IncompleteArrayType>(AT)) |
| return 0; |
| |
| // See if this is a string literal or @encode. |
| Init = Init->IgnoreParens(); |
| |
| // Handle @encode, which is a narrow string. |
| if (isa<ObjCEncodeExpr>(Init) && AT->getElementType()->isCharType()) |
| return Init; |
| |
| // Otherwise we can only handle string literals. |
| StringLiteral *SL = dyn_cast<StringLiteral>(Init); |
| if (SL == 0) return 0; |
| |
| QualType ElemTy = Context.getCanonicalType(AT->getElementType()); |
| // char array can be initialized with a narrow string. |
| // Only allow char x[] = "foo"; not char x[] = L"foo"; |
| if (!SL->isWide()) |
| return ElemTy->isCharType() ? Init : 0; |
| |
| // 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; |
| } |
| |
| static bool CheckSingleInitializer(Expr *&Init, QualType DeclType, |
| bool DirectInit, Sema &S) { |
| // Get the type before calling CheckSingleAssignmentConstraints(), since |
| // it can promote the expression. |
| QualType InitType = Init->getType(); |
| |
| if (S.getLangOptions().CPlusPlus) { |
| // FIXME: I dislike this error message. A lot. |
| if (S.PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) |
| return S.Diag(Init->getSourceRange().getBegin(), |
| diag::err_typecheck_convert_incompatible) |
| << DeclType << Init->getType() << "initializing" |
| << Init->getSourceRange(); |
| return false; |
| } |
| |
| Sema::AssignConvertType ConvTy = |
| S.CheckSingleAssignmentConstraints(DeclType, Init); |
| return S.DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, |
| InitType, Init, "initializing"); |
| } |
| |
| static void CheckStringInit(Expr *Str, QualType &DeclT, Sema &S) { |
| // Get the length of the string as parsed. |
| uint64_t StrLength = |
| cast<ConstantArrayType>(Str->getType())->getSize().getZExtValue(); |
| |
| |
| const ArrayType *AT = S.Context.getAsArrayType(DeclT); |
| if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(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.getConstantArrayWithoutExprType(IAT->getElementType(), |
| ConstVal, |
| ArrayType::Normal, 0); |
| return; |
| } |
| |
| const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); |
| |
| // C99 6.7.8p14. 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 (StrLength-1 > CAT->getSize().getZExtValue()) |
| S.Diag(Str->getSourceRange().getBegin(), |
| 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); |
| } |
| |
| bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, |
| SourceLocation InitLoc, |
| DeclarationName InitEntity, bool DirectInit) { |
| if (DeclType->isDependentType() || |
| Init->isTypeDependent() || Init->isValueDependent()) |
| return false; |
| |
| // C++ [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. |
| if (DeclType->isReferenceType()) |
| return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); |
| |
| // C99 6.7.8p3: The type of the entity to be initialized shall be an array |
| // of unknown size ("[]") or an object type that is not a variable array type. |
| if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) |
| return Diag(InitLoc, diag::err_variable_object_no_init) |
| << VAT->getSizeExpr()->getSourceRange(); |
| |
| InitListExpr *InitList = dyn_cast<InitListExpr>(Init); |
| if (!InitList) { |
| // FIXME: Handle wide strings |
| if (Expr *Str = IsStringInit(Init, DeclType, Context)) { |
| CheckStringInit(Str, DeclType, *this); |
| return false; |
| } |
| |
| // C++ [dcl.init]p14: |
| // -- If the destination type is a (possibly cv-qualified) class |
| // type: |
| if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { |
| QualType DeclTypeC = Context.getCanonicalType(DeclType); |
| QualType InitTypeC = Context.getCanonicalType(Init->getType()); |
| |
| // -- 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 ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || |
| IsDerivedFrom(InitTypeC, DeclTypeC)) { |
| const CXXRecordDecl *RD = |
| cast<CXXRecordDecl>(DeclType->getAs<RecordType>()->getDecl()); |
| |
| // No need to make a CXXConstructExpr if both the ctor and dtor are |
| // trivial. |
| if (RD->hasTrivialConstructor() && RD->hasTrivialDestructor()) |
| return false; |
| |
| CXXConstructorDecl *Constructor |
| = PerformInitializationByConstructor(DeclType, &Init, 1, |
| InitLoc, Init->getSourceRange(), |
| InitEntity, |
| DirectInit? IK_Direct : IK_Copy); |
| if (!Constructor) |
| return true; |
| bool Elidable = (isa<CallExpr>(Init) || |
| isa<CXXTemporaryObjectExpr>(Init)); |
| Init = BuildCXXConstructExpr(Context, |
| DeclType, Constructor, Elidable, &Init, 1); |
| Init = MaybeCreateCXXExprWithTemporaries(Init, /*DestroyTemps=*/true); |
| return false; |
| } |
| |
| // -- 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). If the conversion cannot be done or is |
| // ambiguous, the initialization is ill-formed. The |
| // function selected is called with the initializer |
| // expression as its argument; if the function is a |
| // constructor, the call initializes a temporary of the |
| // destination type. |
| // FIXME: We're pretending to do copy elision here; return to this when we |
| // have ASTs for such things. |
| if (!PerformImplicitConversion(Init, DeclType, "initializing")) |
| return false; |
| |
| if (InitEntity) |
| return Diag(InitLoc, diag::err_cannot_initialize_decl) |
| << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) |
| << Init->getType() << Init->getSourceRange(); |
| return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) |
| << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) |
| << Init->getType() << Init->getSourceRange(); |
| } |
| |
| // C99 6.7.8p16. |
| if (DeclType->isArrayType()) |
| return Diag(Init->getLocStart(), diag::err_array_init_list_required) |
| << Init->getSourceRange(); |
| |
| return CheckSingleInitializer(Init, DeclType, DirectInit, *this); |
| } |
| |
| bool hadError = CheckInitList(InitList, DeclType); |
| Init = InitList; |
| return hadError; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // 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 the "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; |
| std::map<InitListExpr *, InitListExpr *> SyntacticToSemantic; |
| InitListExpr *FullyStructuredList; |
| |
| void CheckImplicitInitList(InitListExpr *ParentIList, QualType T, |
| unsigned &Index, InitListExpr *StructuredList, |
| unsigned &StructuredIndex, |
| bool TopLevelObject = false); |
| void CheckExplicitInitList(InitListExpr *IList, QualType &T, |
| unsigned &Index, InitListExpr *StructuredList, |
| unsigned &StructuredIndex, |
| bool TopLevelObject = false); |
| void CheckListElementTypes(InitListExpr *IList, QualType &DeclType, |
| bool SubobjectIsDesignatorContext, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex, |
| bool TopLevelObject = false); |
| void CheckSubElementType(InitListExpr *IList, QualType ElemType, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex); |
| void CheckScalarType(InitListExpr *IList, QualType DeclType, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex); |
| void CheckReferenceType(InitListExpr *IList, QualType DeclType, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex); |
| void CheckVectorType(InitListExpr *IList, QualType DeclType, unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex); |
| void CheckStructUnionTypes(InitListExpr *IList, QualType DeclType, |
| RecordDecl::field_iterator Field, |
| bool SubobjectIsDesignatorContext, unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex, |
| bool TopLevelObject = false); |
| void CheckArrayType(InitListExpr *IList, QualType &DeclType, |
| llvm::APSInt elementIndex, |
| bool SubobjectIsDesignatorContext, unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex); |
| bool CheckDesignatedInitializer(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 FillInValueInitializations(InitListExpr *ILE); |
| public: |
| InitListChecker(Sema &S, InitListExpr *IL, QualType &T); |
| 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 |
| |
| /// Recursively replaces NULL values within the given initializer list |
| /// with expressions that perform value-initialization of the |
| /// appropriate type. |
| void InitListChecker::FillInValueInitializations(InitListExpr *ILE) { |
| assert((ILE->getType() != SemaRef.Context.VoidTy) && |
| "Should not have void type"); |
| SourceLocation Loc = ILE->getSourceRange().getBegin(); |
| if (ILE->getSyntacticForm()) |
| Loc = ILE->getSyntacticForm()->getSourceRange().getBegin(); |
| |
| if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) { |
| unsigned Init = 0, NumInits = ILE->getNumInits(); |
| for (RecordDecl::field_iterator |
| Field = RType->getDecl()->field_begin(), |
| FieldEnd = RType->getDecl()->field_end(); |
| Field != FieldEnd; ++Field) { |
| if (Field->isUnnamedBitfield()) |
| continue; |
| |
| if (Init >= NumInits || !ILE->getInit(Init)) { |
| 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; |
| } else if (SemaRef.CheckValueInitialization(Field->getType(), Loc)) { |
| hadError = true; |
| return; |
| } |
| |
| // FIXME: If value-initialization involves calling a constructor, should |
| // we make that call explicit in the representation (even when it means |
| // extending the initializer list)? |
| if (Init < NumInits && !hadError) |
| ILE->setInit(Init, |
| new (SemaRef.Context) ImplicitValueInitExpr(Field->getType())); |
| } else if (InitListExpr *InnerILE |
| = dyn_cast<InitListExpr>(ILE->getInit(Init))) |
| FillInValueInitializations(InnerILE); |
| ++Init; |
| |
| // Only look at the first initialization of a union. |
| if (RType->getDecl()->isUnion()) |
| break; |
| } |
| |
| return; |
| } |
| |
| QualType ElementType; |
| |
| 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<ConstantArrayType>(AType)) |
| NumElements = CAType->getSize().getZExtValue(); |
| } else if (const VectorType *VType = ILE->getType()->getAsVectorType()) { |
| ElementType = VType->getElementType(); |
| NumElements = VType->getNumElements(); |
| } else |
| ElementType = ILE->getType(); |
| |
| for (unsigned Init = 0; Init != NumElements; ++Init) { |
| if (Init >= NumInits || !ILE->getInit(Init)) { |
| if (SemaRef.CheckValueInitialization(ElementType, Loc)) { |
| hadError = true; |
| return; |
| } |
| |
| // FIXME: If value-initialization involves calling a constructor, should |
| // we make that call explicit in the representation (even when it means |
| // extending the initializer list)? |
| if (Init < NumInits && !hadError) |
| ILE->setInit(Init, |
| new (SemaRef.Context) ImplicitValueInitExpr(ElementType)); |
| } else if (InitListExpr *InnerILE |
| = dyn_cast<InitListExpr>(ILE->getInit(Init))) |
| FillInValueInitializations(InnerILE); |
| } |
| } |
| |
| |
| InitListChecker::InitListChecker(Sema &S, InitListExpr *IL, QualType &T) |
| : SemaRef(S) { |
| hadError = false; |
| |
| unsigned newIndex = 0; |
| unsigned newStructuredIndex = 0; |
| FullyStructuredList |
| = getStructuredSubobjectInit(IL, newIndex, T, 0, 0, IL->getSourceRange()); |
| CheckExplicitInitList(IL, T, newIndex, FullyStructuredList, newStructuredIndex, |
| /*TopLevelObject=*/true); |
| |
| if (!hadError) |
| FillInValueInitializations(FullyStructuredList); |
| } |
| |
| int InitListChecker::numArrayElements(QualType DeclType) { |
| // FIXME: use a proper constant |
| int maxElements = 0x7FFFFFFF; |
| if (const ConstantArrayType *CAT = |
| SemaRef.Context.getAsConstantArrayType(DeclType)) { |
| maxElements = static_cast<int>(CAT->getSize().getZExtValue()); |
| } |
| return maxElements; |
| } |
| |
| int InitListChecker::numStructUnionElements(QualType DeclType) { |
| RecordDecl *structDecl = DeclType->getAs<RecordType>()->getDecl(); |
| int InitializableMembers = 0; |
| for (RecordDecl::field_iterator |
| Field = structDecl->field_begin(), |
| FieldEnd = structDecl->field_end(); |
| Field != FieldEnd; ++Field) { |
| if ((*Field)->getIdentifier() || !(*Field)->isBitField()) |
| ++InitializableMembers; |
| } |
| if (structDecl->isUnion()) |
| return std::min(InitializableMembers, 1); |
| return InitializableMembers - structDecl->hasFlexibleArrayMember(); |
| } |
| |
| void InitListChecker::CheckImplicitInitList(InitListExpr *ParentIList, |
| QualType T, unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex, |
| bool TopLevelObject) { |
| int maxElements = 0; |
| |
| if (T->isArrayType()) |
| maxElements = numArrayElements(T); |
| else if (T->isStructureType() || T->isUnionType()) |
| maxElements = numStructUnionElements(T); |
| else if (T->isVectorType()) |
| maxElements = T->getAsVectorType()->getNumElements(); |
| else |
| assert(0 && "CheckImplicitInitList(): Illegal type"); |
| |
| if (maxElements == 0) { |
| 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)->getSourceRange().getBegin(), |
| ParentIList->getSourceRange().getEnd())); |
| unsigned StructuredSubobjectInitIndex = 0; |
| |
| // Check the element types and build the structural subobject. |
| unsigned StartIndex = Index; |
| CheckListElementTypes(ParentIList, T, false, Index, |
| StructuredSubobjectInitList, |
| StructuredSubobjectInitIndex, |
| TopLevelObject); |
| unsigned EndIndex = (Index == StartIndex? StartIndex : Index - 1); |
| StructuredSubobjectInitList->setType(T); |
| |
| // 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); |
| } |
| } |
| |
| void InitListChecker::CheckExplicitInitList(InitListExpr *IList, QualType &T, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex, |
| bool TopLevelObject) { |
| assert(IList->isExplicit() && "Illegal Implicit InitListExpr"); |
| SyntacticToSemantic[IList] = StructuredList; |
| StructuredList->setSyntacticForm(IList); |
| CheckListElementTypes(IList, T, true, Index, StructuredList, |
| StructuredIndex, TopLevelObject); |
| IList->setType(T); |
| StructuredList->setType(T); |
| if (hadError) |
| return; |
| |
| if (Index < IList->getNumInits()) { |
| // We have leftover initializers |
| if (StructuredIndex == 1 && |
| IsStringInit(StructuredList->getInit(0), T, SemaRef.Context)) { |
| unsigned DK = diag::warn_excess_initializers_in_char_array_initializer; |
| if (SemaRef.getLangOptions().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.getLangOptions().CPlusPlus) { |
| DK = diag::err_excess_initializers; |
| hadError = true; |
| } |
| if (SemaRef.getLangOptions().OpenCL && initKind == 1) { |
| DK = diag::err_excess_initializers; |
| hadError = true; |
| } |
| |
| SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK) |
| << initKind << IList->getInit(Index)->getSourceRange(); |
| } |
| } |
| |
| if (T->isScalarType() && !TopLevelObject) |
| SemaRef.Diag(IList->getLocStart(), diag::warn_braces_around_scalar_init) |
| << IList->getSourceRange() |
| << CodeModificationHint::CreateRemoval(SourceRange(IList->getLocStart())) |
| << CodeModificationHint::CreateRemoval(SourceRange(IList->getLocEnd())); |
| } |
| |
| void InitListChecker::CheckListElementTypes(InitListExpr *IList, |
| QualType &DeclType, |
| bool SubobjectIsDesignatorContext, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex, |
| bool TopLevelObject) { |
| if (DeclType->isScalarType()) { |
| CheckScalarType(IList, DeclType, Index, StructuredList, StructuredIndex); |
| } else if (DeclType->isVectorType()) { |
| CheckVectorType(IList, DeclType, Index, StructuredList, StructuredIndex); |
| } else if (DeclType->isAggregateType()) { |
| if (DeclType->isRecordType()) { |
| RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); |
| CheckStructUnionTypes(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(IList, DeclType, Zero, SubobjectIsDesignatorContext, Index, |
| StructuredList, StructuredIndex); |
| } else |
| assert(0 && "Aggregate that isn't a structure or array?!"); |
| } else if (DeclType->isVoidType() || DeclType->isFunctionType()) { |
| // This type is invalid, issue a diagnostic. |
| ++Index; |
| 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. |
| SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list) |
| << DeclType << IList->getSourceRange(); |
| hadError = true; |
| } else if (DeclType->isReferenceType()) { |
| CheckReferenceType(IList, DeclType, Index, StructuredList, StructuredIndex); |
| } else { |
| // In C, all types are either scalars or aggregates, but |
| // additional handling is needed here for C++ (and possibly others?). |
| assert(0 && "Unsupported initializer type"); |
| } |
| } |
| |
| void InitListChecker::CheckSubElementType(InitListExpr *IList, |
| QualType ElemType, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex) { |
| Expr *expr = IList->getInit(Index); |
| if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { |
| unsigned newIndex = 0; |
| unsigned newStructuredIndex = 0; |
| InitListExpr *newStructuredList |
| = getStructuredSubobjectInit(IList, Index, ElemType, |
| StructuredList, StructuredIndex, |
| SubInitList->getSourceRange()); |
| CheckExplicitInitList(SubInitList, ElemType, newIndex, |
| newStructuredList, newStructuredIndex); |
| ++StructuredIndex; |
| ++Index; |
| } else if (Expr *Str = IsStringInit(expr, ElemType, SemaRef.Context)) { |
| CheckStringInit(Str, ElemType, SemaRef); |
| UpdateStructuredListElement(StructuredList, StructuredIndex, Str); |
| ++Index; |
| } else if (ElemType->isScalarType()) { |
| CheckScalarType(IList, ElemType, Index, StructuredList, StructuredIndex); |
| } else if (ElemType->isReferenceType()) { |
| CheckReferenceType(IList, ElemType, Index, StructuredList, StructuredIndex); |
| } else { |
| if (SemaRef.getLangOptions().CPlusPlus) { |
| // C++ [dcl.init.aggr]p12: |
| // All implicit type conversions (clause 4) are considered when |
| // initializing the aggregate member with an ini- tializer from |
| // an initializer-list. If the initializer can initialize a |
| // member, the member is initialized. [...] |
| ImplicitConversionSequence ICS |
| = SemaRef.TryCopyInitialization(expr, ElemType); |
| if (ICS.ConversionKind != ImplicitConversionSequence::BadConversion) { |
| if (SemaRef.PerformImplicitConversion(expr, ElemType, ICS, |
| "initializing")) |
| hadError = true; |
| UpdateStructuredListElement(StructuredList, StructuredIndex, expr); |
| ++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. |
| if ((ElemType->isRecordType() || ElemType->isVectorType()) && |
| SemaRef.Context.hasSameUnqualifiedType(expr->getType(), ElemType)) { |
| UpdateStructuredListElement(StructuredList, StructuredIndex, expr); |
| ++Index; |
| return; |
| } |
| |
| // 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 (ElemType->isAggregateType() || ElemType->isVectorType()) { |
| CheckImplicitInitList(IList, ElemType, Index, StructuredList, |
| StructuredIndex); |
| ++StructuredIndex; |
| } else { |
| // We cannot initialize this element, so let |
| // PerformCopyInitialization produce the appropriate diagnostic. |
| SemaRef.PerformCopyInitialization(expr, ElemType, "initializing"); |
| hadError = true; |
| ++Index; |
| ++StructuredIndex; |
| } |
| } |
| } |
| |
| void InitListChecker::CheckScalarType(InitListExpr *IList, QualType DeclType, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex) { |
| if (Index < IList->getNumInits()) { |
| Expr *expr = IList->getInit(Index); |
| if (isa<InitListExpr>(expr)) { |
| SemaRef.Diag(IList->getLocStart(), |
| diag::err_many_braces_around_scalar_init) |
| << IList->getSourceRange(); |
| hadError = true; |
| ++Index; |
| ++StructuredIndex; |
| return; |
| } else if (isa<DesignatedInitExpr>(expr)) { |
| SemaRef.Diag(expr->getSourceRange().getBegin(), |
| diag::err_designator_for_scalar_init) |
| << DeclType << expr->getSourceRange(); |
| hadError = true; |
| ++Index; |
| ++StructuredIndex; |
| return; |
| } |
| |
| Expr *savExpr = expr; // Might be promoted by CheckSingleInitializer. |
| if (CheckSingleInitializer(expr, DeclType, false, SemaRef)) |
| hadError = true; // types weren't compatible. |
| else if (savExpr != expr) { |
| // The type was promoted, update initializer list. |
| IList->setInit(Index, expr); |
| } |
| if (hadError) |
| ++StructuredIndex; |
| else |
| UpdateStructuredListElement(StructuredList, StructuredIndex, expr); |
| ++Index; |
| } else { |
| SemaRef.Diag(IList->getLocStart(), diag::err_empty_scalar_initializer) |
| << IList->getSourceRange(); |
| hadError = true; |
| ++Index; |
| ++StructuredIndex; |
| return; |
| } |
| } |
| |
| void InitListChecker::CheckReferenceType(InitListExpr *IList, QualType DeclType, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex) { |
| if (Index < IList->getNumInits()) { |
| Expr *expr = IList->getInit(Index); |
| if (isa<InitListExpr>(expr)) { |
| SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list) |
| << DeclType << IList->getSourceRange(); |
| hadError = true; |
| ++Index; |
| ++StructuredIndex; |
| return; |
| } |
| |
| Expr *savExpr = expr; // Might be promoted by CheckSingleInitializer. |
| if (SemaRef.CheckReferenceInit(expr, DeclType)) |
| hadError = true; |
| else if (savExpr != expr) { |
| // The type was promoted, update initializer list. |
| IList->setInit(Index, expr); |
| } |
| if (hadError) |
| ++StructuredIndex; |
| else |
| UpdateStructuredListElement(StructuredList, StructuredIndex, expr); |
| ++Index; |
| } else { |
| // 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. |
| SemaRef.Diag(IList->getLocStart(), |
| diag::err_init_reference_member_uninitialized) |
| << DeclType |
| << IList->getSourceRange(); |
| hadError = true; |
| ++Index; |
| ++StructuredIndex; |
| return; |
| } |
| } |
| |
| void InitListChecker::CheckVectorType(InitListExpr *IList, QualType DeclType, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex) { |
| if (Index < IList->getNumInits()) { |
| const VectorType *VT = DeclType->getAsVectorType(); |
| int maxElements = VT->getNumElements(); |
| QualType elementType = VT->getElementType(); |
| |
| for (int i = 0; i < maxElements; ++i) { |
| // Don't attempt to go past the end of the init list |
| if (Index >= IList->getNumInits()) |
| break; |
| CheckSubElementType(IList, elementType, Index, |
| StructuredList, StructuredIndex); |
| } |
| } |
| } |
| |
| void InitListChecker::CheckArrayType(InitListExpr *IList, QualType &DeclType, |
| llvm::APSInt elementIndex, |
| bool SubobjectIsDesignatorContext, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex) { |
| // Check for the special-case of initializing an array with a string. |
| if (Index < IList->getNumInits()) { |
| if (Expr *Str = IsStringInit(IList->getInit(Index), DeclType, |
| SemaRef.Context)) { |
| CheckStringInit(Str, DeclType, SemaRef); |
| // 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. |
| UpdateStructuredListElement(StructuredList, StructuredIndex, Str); |
| StructuredList->resizeInits(SemaRef.Context, StructuredIndex); |
| ++Index; |
| return; |
| } |
| } |
| if (const VariableArrayType *VAT = |
| SemaRef.Context.getAsVariableArrayType(DeclType)) { |
| // 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). |
| 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 = |
| SemaRef.Context.getAsConstantArrayType(DeclType)) { |
| maxElements = CAT->getSize(); |
| elementIndex.extOrTrunc(maxElements.getBitWidth()); |
| elementIndex.setIsUnsigned(maxElements.isUnsigned()); |
| maxElementsKnown = true; |
| } |
| |
| QualType elementType = SemaRef.Context.getAsArrayType(DeclType) |
| ->getElementType(); |
| while (Index < IList->getNumInits()) { |
| Expr *Init = IList->getInit(Index); |
| if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(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(IList, DIE, 0, |
| DeclType, 0, &elementIndex, Index, |
| StructuredList, StructuredIndex, true, |
| false)) { |
| hadError = true; |
| continue; |
| } |
| |
| if (elementIndex.getBitWidth() > maxElements.getBitWidth()) |
| maxElements.extend(elementIndex.getBitWidth()); |
| else if (elementIndex.getBitWidth() < maxElements.getBitWidth()) |
| 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; |
| |
| // Check this element. |
| CheckSubElementType(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()) { |
| // 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); |
| } |
| } |
| |
| void InitListChecker::CheckStructUnionTypes(InitListExpr *IList, |
| QualType DeclType, |
| RecordDecl::field_iterator Field, |
| bool SubobjectIsDesignatorContext, |
| unsigned &Index, |
| InitListExpr *StructuredList, |
| unsigned &StructuredIndex, |
| bool TopLevelObject) { |
| RecordDecl* structDecl = DeclType->getAs<RecordType>()->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<RecordType>()->getDecl(); |
| for (RecordDecl::field_iterator FieldEnd = RD->field_end(); |
| Field != FieldEnd; ++Field) { |
| if (Field->getDeclName()) { |
| 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<RecordType>()->getDecl(); |
| RecordDecl::field_iterator FieldEnd = RD->field_end(); |
| bool InitializedSomething = false; |
| while (Index < IList->getNumInits()) { |
| Expr *Init = IList->getInit(Index); |
| |
| if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(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(IList, DIE, 0, |
| DeclType, &Field, 0, Index, |
| StructuredList, StructuredIndex, |
| true, TopLevelObject)) |
| hadError = true; |
| |
| InitializedSomething = true; |
| 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; |
| } |
| |
| CheckSubElementType(IList, Field->getType(), Index, |
| StructuredList, StructuredIndex); |
| InitializedSomething = true; |
| |
| if (DeclType->isUnionType()) { |
| // Initialize the first field within the union. |
| StructuredList->setInitializedFieldInUnion(*Field); |
| } |
| |
| ++Field; |
| } |
| |
| if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() || |
| Index >= IList->getNumInits()) |
| return; |
| |
| // Handle GNU flexible array initializers. |
| if (!TopLevelObject && |
| (!isa<InitListExpr>(IList->getInit(Index)) || |
| cast<InitListExpr>(IList->getInit(Index))->getNumInits() > 0)) { |
| SemaRef.Diag(IList->getInit(Index)->getSourceRange().getBegin(), |
| diag::err_flexible_array_init_nonempty) |
| << IList->getInit(Index)->getSourceRange().getBegin(); |
| SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) |
| << *Field; |
| hadError = true; |
| ++Index; |
| return; |
| } else { |
| SemaRef.Diag(IList->getInit(Index)->getSourceRange().getBegin(), |
| diag::ext_flexible_array_init) |
| << IList->getInit(Index)->getSourceRange().getBegin(); |
| SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) |
| << *Field; |
| } |
| |
| if (isa<InitListExpr>(IList->getInit(Index))) |
| CheckSubElementType(IList, Field->getType(), Index, StructuredList, |
| StructuredIndex); |
| else |
| CheckImplicitInitList(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. |
| /// |
| /// Field/FieldIndex will be updated to point to the (new) |
| /// currently-designated field. |
| static void ExpandAnonymousFieldDesignator(Sema &SemaRef, |
| DesignatedInitExpr *DIE, |
| unsigned DesigIdx, |
| FieldDecl *Field, |
| RecordDecl::field_iterator &FieldIter, |
| unsigned &FieldIndex) { |
| typedef DesignatedInitExpr::Designator Designator; |
| |
| // Build the path from the current object to the member of the |
| // anonymous struct/union (backwards). |
| llvm::SmallVector<FieldDecl *, 4> Path; |
| SemaRef.BuildAnonymousStructUnionMemberPath(Field, Path); |
| |
| // Build the replacement designators. |
| llvm::SmallVector<Designator, 4> Replacements; |
| for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator |
| FI = Path.rbegin(), FIEnd = Path.rend(); |
| FI != FIEnd; ++FI) { |
| if (FI + 1 == FIEnd) |
| Replacements.push_back(Designator((IdentifierInfo *)0, |
| DIE->getDesignator(DesigIdx)->getDotLoc(), |
| DIE->getDesignator(DesigIdx)->getFieldLoc())); |
| else |
| Replacements.push_back(Designator((IdentifierInfo *)0, SourceLocation(), |
| SourceLocation())); |
| Replacements.back().setField(*FI); |
| } |
| |
| // 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(DesigIdx, &Replacements[0], |
| &Replacements[0] + Replacements.size()); |
| |
| // Update FieldIter/FieldIndex; |
| RecordDecl *Record = cast<RecordDecl>(Path.back()->getDeclContext()); |
| FieldIter = Record->field_begin(); |
| FieldIndex = 0; |
| for (RecordDecl::field_iterator FEnd = Record->field_end(); |
| FieldIter != FEnd; ++FieldIter) { |
| if (FieldIter->isUnnamedBitfield()) |
| continue; |
| |
| if (*FieldIter == Path.back()) |
| return; |
| |
| ++FieldIndex; |
| } |
| |
| assert(false && "Unable to find anonymous struct/union field"); |
| } |
| |
| /// @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(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(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; |
| } |
| |
| bool IsFirstDesignator = (DesigIdx == 0); |
| assert((IsFirstDesignator || StructuredList) && |
| "Need a non-designated initializer list to start from"); |
| |
| DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx); |
| // Determine the structural initializer list that corresponds to the |
| // current subobject. |
| StructuredList = IsFirstDesignator? SyntacticToSemantic[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<RecordType>(); |
| if (!RT) { |
| SourceLocation Loc = D->getDotLoc(); |
| if (Loc.isInvalid()) |
| Loc = D->getFieldLoc(); |
| SemaRef.Diag(Loc, diag::err_field_designator_non_aggr) |
| << SemaRef.getLangOptions().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 (KnownField == *Field || Field->getIdentifier() == FieldName) |
| break; |
| |
| ++FieldIndex; |
| } |
| |
| if (Field == FieldEnd) { |
| // 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); |
| if (Lookup.first == Lookup.second) { |
| // Name lookup didn't find anything. |
| SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown) |
| << FieldName << CurrentObjectType; |
| ++Index; |
| return true; |
| } else if (!KnownField && isa<FieldDecl>(*Lookup.first) && |
| cast<RecordDecl>((*Lookup.first)->getDeclContext()) |
| ->isAnonymousStructOrUnion()) { |
| // Handle an field designator that refers to a member of an |
| // anonymous struct or union. |
| ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, |
| cast<FieldDecl>(*Lookup.first), |
| Field, FieldIndex); |
| D = DIE->getDesignator(DesigIdx); |
| } else { |
| // 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; |
| } |
| } else if (!KnownField && |
| cast<RecordDecl>((*Field)->getDeclContext()) |
| ->isAnonymousStructOrUnion()) { |
| ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, *Field, |
| Field, FieldIndex); |
| D = DIE->getDesignator(DesigIdx); |
| } |
| |
| // All of the fields of a union are located at the same place in |
| // the initializer list. |
| if (RT->getDecl()->isUnion()) { |
| FieldIndex = 0; |
| StructuredList->setInitializedFieldInUnion(*Field); |
| } |
| |
| // 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). |
| 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<InitListExpr>(DIE->getInit())) { |
| // The initializer is not an initializer list. |
| SemaRef.Diag(DIE->getInit()->getSourceRange().getBegin(), |
| diag::err_flexible_array_init_needs_braces) |
| << DIE->getInit()->getSourceRange(); |
| SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) |
| << *Field; |
| Invalid = true; |
| } |
| |
| // Handle GNU flexible array initializers. |
| if (!Invalid && !TopLevelObject && |
| cast<InitListExpr>(DIE->getInit())->getNumInits() > 0) { |
| SemaRef.Diag(DIE->getSourceRange().getBegin(), |
| diag::err_flexible_array_init_nonempty) |
| << DIE->getSourceRange().getBegin(); |
| SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) |
| << *Field; |
| Invalid = true; |
| } |
| |
| if (Invalid) { |
| ++Index; |
| return true; |
| } |
| |
| // Initialize the array. |
| bool prevHadError = hadError; |
| unsigned newStructuredIndex = FieldIndex; |
| unsigned OldIndex = Index; |
| IList->setInit(Index, DIE->getInit()); |
| CheckSubElementType(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; |
| if (CheckDesignatedInitializer(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(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) { |
| 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->EvaluateAsInt(SemaRef.Context); |
| DesignatedEndIndex = DesignatedStartIndex; |
| } else { |
| assert(D->isArrayRangeDesignator() && "Need array-range designator"); |
| |
| |
| DesignatedStartIndex = |
| DIE->getArrayRangeStart(*D)->EvaluateAsInt(SemaRef.Context); |
| DesignatedEndIndex = |
| DIE->getArrayRangeEnd(*D)->EvaluateAsInt(SemaRef.Context); |
| IndexExpr = DIE->getArrayRangeEnd(*D); |
| |
| if (DesignatedStartIndex.getZExtValue() !=DesignatedEndIndex.getZExtValue()) |
| FullyStructuredList->sawArrayRangeDesignator(); |
| } |
| |
| if (isa<ConstantArrayType>(AT)) { |
| llvm::APSInt MaxElements(cast<ConstantArrayType>(AT)->getSize(), false); |
| DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth()); |
| DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned()); |
| DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth()); |
| DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned()); |
| if (DesignatedEndIndex >= MaxElements) { |
| SemaRef.Diag(IndexExpr->getSourceRange().getBegin(), |
| 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.extend(DesignatedStartIndex.getBitWidth()); |
| else if (DesignatedStartIndex.getBitWidth() < |
| DesignatedEndIndex.getBitWidth()) |
| 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 (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; |
| while (DesignatedStartIndex <= DesignatedEndIndex) { |
| // Recurse to check later designated subobjects. |
| QualType ElementType = AT->getElementType(); |
| Index = OldIndex; |
| if (CheckDesignatedInitializer(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(IList, CurrentObjectType, DesignatedStartIndex, 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) { |
| Expr *ExistingInit = 0; |
| if (!StructuredList) |
| ExistingInit = SyntacticToSemantic[IList]; |
| else if (StructuredIndex < StructuredList->getNumInits()) |
| ExistingInit = StructuredList->getInit(StructuredIndex); |
| |
| if (InitListExpr *Result = dyn_cast_or_null<InitListExpr>(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->getSourceRange().getBegin(), |
| diag::note_previous_initializer) |
| << /*FIXME:has side effects=*/0 |
| << ExistingInit->getSourceRange(); |
| } |
| |
| InitListExpr *Result |
| = new (SemaRef.Context) InitListExpr(InitRange.getBegin(), 0, 0, |
| InitRange.getEnd()); |
| |
| Result->setType(CurrentObjectType); |
| |
| // Pre-allocate storage for the structured initializer list. |
| unsigned NumElements = 0; |
| unsigned NumInits = 0; |
| if (!StructuredList) |
| NumInits = IList->getNumInits(); |
| else if (Index < IList->getNumInits()) { |
| if (InitListExpr *SubList = dyn_cast<InitListExpr>(IList->getInit(Index))) |
| NumInits = SubList->getNumInits(); |
| } |
| |
| if (const ArrayType *AType |
| = SemaRef.Context.getAsArrayType(CurrentObjectType)) { |
| if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(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 (NumInits && NumElements > NumInits) |
| NumElements = 0; |
| } |
| } else if (const VectorType *VType = CurrentObjectType->getAsVectorType()) |
| NumElements = VType->getNumElements(); |
| else if (const RecordType *RType = CurrentObjectType->getAs<RecordType>()) { |
| RecordDecl *RDecl = RType->getDecl(); |
| if (RDecl->isUnion()) |
| NumElements = 1; |
| else |
| NumElements = std::distance(RDecl->field_begin(), |
| RDecl->field_end()); |
| } |
| |
| if (NumElements < NumInits) |
| NumElements = IList->getNumInits(); |
| |
| Result->reserveInits(NumElements); |
| |
| // Link this new initializer list into the structured initializer |
| // lists. |
| if (StructuredList) |
| StructuredList->updateInit(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(StructuredIndex, expr)) { |
| // This initializer overwrites a previous initializer. Warn. |
| SemaRef.Diag(expr->getSourceRange().getBegin(), |
| diag::warn_initializer_overrides) |
| << expr->getSourceRange(); |
| SemaRef.Diag(PrevInit->getSourceRange().getBegin(), |
| 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 essentailly just a wrapper around |
| /// VerifyIntegerConstantExpression that also checks for negative values |
| /// and produces a reasonable diagnostic if there is a |
| /// failure. Returns true if there was an error, false otherwise. If |
| /// everything went okay, Value will receive the value of the constant |
| /// expression. |
| static bool |
| CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) { |
| SourceLocation Loc = Index->getSourceRange().getBegin(); |
| |
| // Make sure this is an integer constant expression. |
| if (S.VerifyIntegerConstantExpression(Index, &Value)) |
| return true; |
| |
| if (Value.isSigned() && Value.isNegative()) |
| return S.Diag(Loc, diag::err_array_designator_negative) |
| << Value.toString(10) << Index->getSourceRange(); |
| |
| Value.setIsUnsigned(true); |
| return false; |
| } |
| |
| Sema::OwningExprResult Sema::ActOnDesignatedInitializer(Designation &Desig, |
| SourceLocation Loc, |
| bool GNUSyntax, |
| OwningExprResult Init) { |
| typedef DesignatedInitExpr::Designator ASTDesignator; |
| |
| bool Invalid = false; |
| llvm::SmallVector<ASTDesignator, 32> Designators; |
| llvm::SmallVector<Expr *, 32> 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<Expr *>(D.getArrayIndex()); |
| llvm::APSInt IndexValue; |
| if (!Index->isTypeDependent() && |
| !Index->isValueDependent() && |
| CheckArrayDesignatorExpr(*this, Index, IndexValue)) |
| 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<Expr *>(D.getArrayRangeStart()); |
| Expr *EndIndex = static_cast<Expr *>(D.getArrayRangeEnd()); |
| llvm::APSInt StartValue; |
| llvm::APSInt EndValue; |
| bool StartDependent = StartIndex->isTypeDependent() || |
| StartIndex->isValueDependent(); |
| bool EndDependent = EndIndex->isTypeDependent() || |
| EndIndex->isValueDependent(); |
| if ((!StartDependent && |
| CheckArrayDesignatorExpr(*this, StartIndex, StartValue)) || |
| (!EndDependent && |
| CheckArrayDesignatorExpr(*this, EndIndex, EndValue))) |
| 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.extend(StartValue.getBitWidth()); |
| else if (StartValue.getBitWidth() < EndValue.getBitWidth()) |
| 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<Expr>()); |
| return Owned(DIE); |
| } |
| |
| bool Sema::CheckInitList(InitListExpr *&InitList, QualType &DeclType) { |
| InitListChecker CheckInitList(*this, InitList, DeclType); |
| if (!CheckInitList.HadError()) |
| InitList = CheckInitList.getFullyStructuredList(); |
| |
| return CheckInitList.HadError(); |
| } |
| |
| /// \brief Diagnose any semantic errors with value-initialization of |
| /// the given type. |
| /// |
| /// Value-initialization effectively zero-initializes any types |
| /// without user-declared constructors, and calls the default |
| /// constructor for a for any type that has a user-declared |
| /// constructor (C++ [dcl.init]p5). Value-initialization can fail when |
| /// a type with a user-declared constructor does not have an |
| /// accessible, non-deleted default constructor. In C, everything can |
| /// be value-initialized, which corresponds to C's notion of |
| /// initializing objects with static storage duration when no |
| /// initializer is provided for that object. |
| /// |
| /// \returns true if there was an error, false otherwise. |
| bool Sema::CheckValueInitialization(QualType Type, SourceLocation Loc) { |
| // C++ [dcl.init]p5: |
| // |
| // To value-initialize an object of type T means: |
| |
| // -- if T is an array type, then each element is value-initialized; |
| if (const ArrayType *AT = Context.getAsArrayType(Type)) |
| return CheckValueInitialization(AT->getElementType(), Loc); |
| |
| if (const RecordType *RT = Type->getAs<RecordType>()) { |
| if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) { |
| // -- 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 (ClassDecl->hasUserDeclaredConstructor()) |
| // FIXME: Eventually, we'll need to put the constructor decl into the |
| // AST. |
| return PerformInitializationByConstructor(Type, 0, 0, Loc, |
| SourceRange(Loc), |
| DeclarationName(), |
| IK_Direct); |
| } |
| } |
| |
| if (Type->isReferenceType()) { |
| // C++ [dcl.init]p5: |
| // [...] A program that calls for default-initialization or |
| // value-initialization of an entity of reference type is |
| // ill-formed. [...] |
| // FIXME: Once we have code that goes through this path, add an actual |
| // diagnostic :) |
| } |
| |
| return false; |
| } |