| //===------ SemaDeclCXX.cpp - Semantic Analysis for C++ Declarations ------===// |
| // |
| // 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 C++ declarations. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "Sema.h" |
| #include "clang/AST/ASTConsumer.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/TypeOrdering.h" |
| #include "clang/AST/StmtVisitor.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "clang/Basic/Diagnostic.h" |
| #include "clang/Parse/DeclSpec.h" |
| #include "llvm/Support/Compiler.h" |
| #include <algorithm> // for std::equal |
| #include <map> |
| |
| using namespace clang; |
| |
| //===----------------------------------------------------------------------===// |
| // CheckDefaultArgumentVisitor |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| /// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses |
| /// the default argument of a parameter to determine whether it |
| /// contains any ill-formed subexpressions. For example, this will |
| /// diagnose the use of local variables or parameters within the |
| /// default argument expression. |
| class VISIBILITY_HIDDEN CheckDefaultArgumentVisitor |
| : public StmtVisitor<CheckDefaultArgumentVisitor, bool> { |
| Expr *DefaultArg; |
| Sema *S; |
| |
| public: |
| CheckDefaultArgumentVisitor(Expr *defarg, Sema *s) |
| : DefaultArg(defarg), S(s) {} |
| |
| bool VisitExpr(Expr *Node); |
| bool VisitDeclRefExpr(DeclRefExpr *DRE); |
| }; |
| |
| /// VisitExpr - Visit all of the children of this expression. |
| bool CheckDefaultArgumentVisitor::VisitExpr(Expr *Node) { |
| bool IsInvalid = false; |
| for (Stmt::child_iterator I = Node->child_begin(), |
| E = Node->child_end(); I != E; ++I) |
| IsInvalid |= Visit(*I); |
| return IsInvalid; |
| } |
| |
| /// VisitDeclRefExpr - Visit a reference to a declaration, to |
| /// determine whether this declaration can be used in the default |
| /// argument expression. |
| bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) { |
| NamedDecl *Decl = DRE->getDecl(); |
| if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) { |
| // C++ [dcl.fct.default]p9 |
| // Default arguments are evaluated each time the function is |
| // called. The order of evaluation of function arguments is |
| // unspecified. Consequently, parameters of a function shall not |
| // be used in default argument expressions, even if they are not |
| // evaluated. Parameters of a function declared before a default |
| // argument expression are in scope and can hide namespace and |
| // class member names. |
| return S->Diag(DRE->getSourceRange().getBegin(), |
| diag::err_param_default_argument_references_param, |
| Param->getName(), DefaultArg->getSourceRange()); |
| } else if (VarDecl *VDecl = dyn_cast<VarDecl>(Decl)) { |
| // C++ [dcl.fct.default]p7 |
| // Local variables shall not be used in default argument |
| // expressions. |
| if (VDecl->isBlockVarDecl()) |
| return S->Diag(DRE->getSourceRange().getBegin(), |
| diag::err_param_default_argument_references_local, |
| VDecl->getName(), DefaultArg->getSourceRange()); |
| } |
| |
| // FIXME: when Clang has support for member functions, "this" |
| // will also need to be diagnosed. |
| |
| return false; |
| } |
| } |
| |
| /// ActOnParamDefaultArgument - Check whether the default argument |
| /// provided for a function parameter is well-formed. If so, attach it |
| /// to the parameter declaration. |
| void |
| Sema::ActOnParamDefaultArgument(DeclTy *param, SourceLocation EqualLoc, |
| ExprTy *defarg) { |
| ParmVarDecl *Param = (ParmVarDecl *)param; |
| llvm::OwningPtr<Expr> DefaultArg((Expr *)defarg); |
| QualType ParamType = Param->getType(); |
| |
| // Default arguments are only permitted in C++ |
| if (!getLangOptions().CPlusPlus) { |
| Diag(EqualLoc, diag::err_param_default_argument, |
| DefaultArg->getSourceRange()); |
| return; |
| } |
| |
| // C++ [dcl.fct.default]p5 |
| // A default argument expression is implicitly converted (clause |
| // 4) to the parameter type. The default argument expression has |
| // the same semantic constraints as the initializer expression in |
| // a declaration of a variable of the parameter type, using the |
| // copy-initialization semantics (8.5). |
| // |
| // FIXME: CheckSingleAssignmentConstraints has the wrong semantics |
| // for C++ (since we want copy-initialization, not copy-assignment), |
| // but we don't have the right semantics implemented yet. Because of |
| // this, our error message is also very poor. |
| QualType DefaultArgType = DefaultArg->getType(); |
| Expr *DefaultArgPtr = DefaultArg.get(); |
| AssignConvertType ConvTy = CheckSingleAssignmentConstraints(ParamType, |
| DefaultArgPtr); |
| if (DefaultArgPtr != DefaultArg.get()) { |
| DefaultArg.take(); |
| DefaultArg.reset(DefaultArgPtr); |
| } |
| if (DiagnoseAssignmentResult(ConvTy, DefaultArg->getLocStart(), |
| ParamType, DefaultArgType, DefaultArg.get(), |
| "in default argument")) { |
| return; |
| } |
| |
| // Check that the default argument is well-formed |
| CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg.get(), this); |
| if (DefaultArgChecker.Visit(DefaultArg.get())) |
| return; |
| |
| // Okay: add the default argument to the parameter |
| Param->setDefaultArg(DefaultArg.take()); |
| } |
| |
| /// CheckExtraCXXDefaultArguments - Check for any extra default |
| /// arguments in the declarator, which is not a function declaration |
| /// or definition and therefore is not permitted to have default |
| /// arguments. This routine should be invoked for every declarator |
| /// that is not a function declaration or definition. |
| void Sema::CheckExtraCXXDefaultArguments(Declarator &D) { |
| // C++ [dcl.fct.default]p3 |
| // A default argument expression shall be specified only in the |
| // parameter-declaration-clause of a function declaration or in a |
| // template-parameter (14.1). It shall not be specified for a |
| // parameter pack. If it is specified in a |
| // parameter-declaration-clause, it shall not occur within a |
| // declarator or abstract-declarator of a parameter-declaration. |
| for (unsigned i = 0; i < D.getNumTypeObjects(); ++i) { |
| DeclaratorChunk &chunk = D.getTypeObject(i); |
| if (chunk.Kind == DeclaratorChunk::Function) { |
| for (unsigned argIdx = 0; argIdx < chunk.Fun.NumArgs; ++argIdx) { |
| ParmVarDecl *Param = (ParmVarDecl *)chunk.Fun.ArgInfo[argIdx].Param; |
| if (Param->getDefaultArg()) { |
| Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc, |
| Param->getDefaultArg()->getSourceRange()); |
| Param->setDefaultArg(0); |
| } |
| } |
| } |
| } |
| } |
| |
| // MergeCXXFunctionDecl - Merge two declarations of the same C++ |
| // function, once we already know that they have the same |
| // type. Subroutine of MergeFunctionDecl. |
| FunctionDecl * |
| Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old) { |
| // C++ [dcl.fct.default]p4: |
| // |
| // For non-template functions, default arguments can be added in |
| // later declarations of a function in the same |
| // scope. Declarations in different scopes have completely |
| // distinct sets of default arguments. That is, declarations in |
| // inner scopes do not acquire default arguments from |
| // declarations in outer scopes, and vice versa. In a given |
| // function declaration, all parameters subsequent to a |
| // parameter with a default argument shall have default |
| // arguments supplied in this or previous declarations. A |
| // default argument shall not be redefined by a later |
| // declaration (not even to the same value). |
| for (unsigned p = 0, NumParams = Old->getNumParams(); p < NumParams; ++p) { |
| ParmVarDecl *OldParam = Old->getParamDecl(p); |
| ParmVarDecl *NewParam = New->getParamDecl(p); |
| |
| if(OldParam->getDefaultArg() && NewParam->getDefaultArg()) { |
| Diag(NewParam->getLocation(), |
| diag::err_param_default_argument_redefinition, |
| NewParam->getDefaultArg()->getSourceRange()); |
| Diag(OldParam->getLocation(), diag::err_previous_definition); |
| } else if (OldParam->getDefaultArg()) { |
| // Merge the old default argument into the new parameter |
| NewParam->setDefaultArg(OldParam->getDefaultArg()); |
| } |
| } |
| |
| return New; |
| } |
| |
| /// CheckCXXDefaultArguments - Verify that the default arguments for a |
| /// function declaration are well-formed according to C++ |
| /// [dcl.fct.default]. |
| void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) { |
| unsigned NumParams = FD->getNumParams(); |
| unsigned p; |
| |
| // Find first parameter with a default argument |
| for (p = 0; p < NumParams; ++p) { |
| ParmVarDecl *Param = FD->getParamDecl(p); |
| if (Param->getDefaultArg()) |
| break; |
| } |
| |
| // C++ [dcl.fct.default]p4: |
| // In a given function declaration, all parameters |
| // subsequent to a parameter with a default argument shall |
| // have default arguments supplied in this or previous |
| // declarations. A default argument shall not be redefined |
| // by a later declaration (not even to the same value). |
| unsigned LastMissingDefaultArg = 0; |
| for(; p < NumParams; ++p) { |
| ParmVarDecl *Param = FD->getParamDecl(p); |
| if (!Param->getDefaultArg()) { |
| if (Param->getIdentifier()) |
| Diag(Param->getLocation(), |
| diag::err_param_default_argument_missing_name, |
| Param->getIdentifier()->getName()); |
| else |
| Diag(Param->getLocation(), |
| diag::err_param_default_argument_missing); |
| |
| LastMissingDefaultArg = p; |
| } |
| } |
| |
| if (LastMissingDefaultArg > 0) { |
| // Some default arguments were missing. Clear out all of the |
| // default arguments up to (and including) the last missing |
| // default argument, so that we leave the function parameters |
| // in a semantically valid state. |
| for (p = 0; p <= LastMissingDefaultArg; ++p) { |
| ParmVarDecl *Param = FD->getParamDecl(p); |
| if (Param->getDefaultArg()) { |
| delete Param->getDefaultArg(); |
| Param->setDefaultArg(0); |
| } |
| } |
| } |
| } |
| |
| /// isCurrentClassName - Determine whether the identifier II is the |
| /// name of the class type currently being defined. In the case of |
| /// nested classes, this will only return true if II is the name of |
| /// the innermost class. |
| bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *) { |
| if (CXXRecordDecl *CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext)) |
| return &II == CurDecl->getIdentifier(); |
| else |
| return false; |
| } |
| |
| /// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is |
| /// one entry in the base class list of a class specifier, for |
| /// example: |
| /// class foo : public bar, virtual private baz { |
| /// 'public bar' and 'virtual private baz' are each base-specifiers. |
| Sema::BaseResult |
| Sema::ActOnBaseSpecifier(DeclTy *classdecl, SourceRange SpecifierRange, |
| bool Virtual, AccessSpecifier Access, |
| TypeTy *basetype, SourceLocation BaseLoc) { |
| RecordDecl *Decl = (RecordDecl*)classdecl; |
| QualType BaseType = Context.getTypeDeclType((TypeDecl*)basetype); |
| |
| // Base specifiers must be record types. |
| if (!BaseType->isRecordType()) { |
| Diag(BaseLoc, diag::err_base_must_be_class, SpecifierRange); |
| return true; |
| } |
| |
| // C++ [class.union]p1: |
| // A union shall not be used as a base class. |
| if (BaseType->isUnionType()) { |
| Diag(BaseLoc, diag::err_union_as_base_class, SpecifierRange); |
| return true; |
| } |
| |
| // C++ [class.union]p1: |
| // A union shall not have base classes. |
| if (Decl->isUnion()) { |
| Diag(Decl->getLocation(), diag::err_base_clause_on_union, |
| SpecifierRange); |
| return true; |
| } |
| |
| // C++ [class.derived]p2: |
| // The class-name in a base-specifier shall not be an incompletely |
| // defined class. |
| if (BaseType->isIncompleteType()) { |
| Diag(BaseLoc, diag::err_incomplete_base_class, SpecifierRange); |
| return true; |
| } |
| |
| // Create the base specifier. |
| return new CXXBaseSpecifier(SpecifierRange, Virtual, |
| BaseType->isClassType(), Access, BaseType); |
| } |
| |
| /// ActOnBaseSpecifiers - Attach the given base specifiers to the |
| /// class, after checking whether there are any duplicate base |
| /// classes. |
| void Sema::ActOnBaseSpecifiers(DeclTy *ClassDecl, BaseTy **Bases, |
| unsigned NumBases) { |
| if (NumBases == 0) |
| return; |
| |
| // Used to keep track of which base types we have already seen, so |
| // that we can properly diagnose redundant direct base types. Note |
| // that the key is always the unqualified canonical type of the base |
| // class. |
| std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes; |
| |
| // Copy non-redundant base specifiers into permanent storage. |
| CXXBaseSpecifier **BaseSpecs = (CXXBaseSpecifier **)Bases; |
| unsigned NumGoodBases = 0; |
| for (unsigned idx = 0; idx < NumBases; ++idx) { |
| QualType NewBaseType |
| = Context.getCanonicalType(BaseSpecs[idx]->getType()); |
| NewBaseType = NewBaseType.getUnqualifiedType(); |
| |
| if (KnownBaseTypes[NewBaseType]) { |
| // C++ [class.mi]p3: |
| // A class shall not be specified as a direct base class of a |
| // derived class more than once. |
| Diag(BaseSpecs[idx]->getSourceRange().getBegin(), |
| diag::err_duplicate_base_class, |
| KnownBaseTypes[NewBaseType]->getType().getAsString(), |
| BaseSpecs[idx]->getSourceRange()); |
| |
| // Delete the duplicate base class specifier; we're going to |
| // overwrite its pointer later. |
| delete BaseSpecs[idx]; |
| } else { |
| // Okay, add this new base class. |
| KnownBaseTypes[NewBaseType] = BaseSpecs[idx]; |
| BaseSpecs[NumGoodBases++] = BaseSpecs[idx]; |
| } |
| } |
| |
| // Attach the remaining base class specifiers to the derived class. |
| CXXRecordDecl *Decl = (CXXRecordDecl*)ClassDecl; |
| Decl->setBases(BaseSpecs, NumGoodBases); |
| |
| // Delete the remaining (good) base class specifiers, since their |
| // data has been copied into the CXXRecordDecl. |
| for (unsigned idx = 0; idx < NumGoodBases; ++idx) |
| delete BaseSpecs[idx]; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // C++ class member Handling |
| //===----------------------------------------------------------------------===// |
| |
| /// ActOnStartCXXClassDef - This is called at the start of a class/struct/union |
| /// definition, when on C++. |
| void Sema::ActOnStartCXXClassDef(Scope *S, DeclTy *D, SourceLocation LBrace) { |
| CXXRecordDecl *Dcl = cast<CXXRecordDecl>(static_cast<Decl *>(D)); |
| PushDeclContext(Dcl); |
| FieldCollector->StartClass(); |
| |
| if (Dcl->getIdentifier()) { |
| // C++ [class]p2: |
| // [...] The class-name is also inserted into the scope of the |
| // class itself; this is known as the injected-class-name. For |
| // purposes of access checking, the injected-class-name is treated |
| // as if it were a public member name. |
| TypedefDecl *InjectedClassName |
| = TypedefDecl::Create(Context, Dcl, LBrace, Dcl->getIdentifier(), |
| Context.getTypeDeclType(Dcl), /*PrevDecl=*/0); |
| PushOnScopeChains(InjectedClassName, S); |
| } |
| } |
| |
| /// ActOnCXXMemberDeclarator - This is invoked when a C++ class member |
| /// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the |
| /// bitfield width if there is one and 'InitExpr' specifies the initializer if |
| /// any. 'LastInGroup' is non-null for cases where one declspec has multiple |
| /// declarators on it. |
| /// |
| /// NOTE: Because of CXXFieldDecl's inability to be chained like ScopedDecls, if |
| /// an instance field is declared, a new CXXFieldDecl is created but the method |
| /// does *not* return it; it returns LastInGroup instead. The other C++ members |
| /// (which are all ScopedDecls) are returned after appending them to |
| /// LastInGroup. |
| Sema::DeclTy * |
| Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D, |
| ExprTy *BW, ExprTy *InitExpr, |
| DeclTy *LastInGroup) { |
| const DeclSpec &DS = D.getDeclSpec(); |
| IdentifierInfo *II = D.getIdentifier(); |
| Expr *BitWidth = static_cast<Expr*>(BW); |
| Expr *Init = static_cast<Expr*>(InitExpr); |
| SourceLocation Loc = D.getIdentifierLoc(); |
| |
| // C++ 9.2p6: A member shall not be declared to have automatic storage |
| // duration (auto, register) or with the extern storage-class-specifier. |
| switch (DS.getStorageClassSpec()) { |
| case DeclSpec::SCS_unspecified: |
| case DeclSpec::SCS_typedef: |
| case DeclSpec::SCS_static: |
| // FALL THROUGH. |
| break; |
| default: |
| if (DS.getStorageClassSpecLoc().isValid()) |
| Diag(DS.getStorageClassSpecLoc(), |
| diag::err_storageclass_invalid_for_member); |
| else |
| Diag(DS.getThreadSpecLoc(), diag::err_storageclass_invalid_for_member); |
| D.getMutableDeclSpec().ClearStorageClassSpecs(); |
| } |
| |
| bool isFunc = D.isFunctionDeclarator(); |
| if (!isFunc && |
| D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_typedef && |
| D.getNumTypeObjects() == 0) { |
| // Check also for this case: |
| // |
| // typedef int f(); |
| // f a; |
| // |
| Decl *TD = static_cast<Decl *>(DS.getTypeRep()); |
| isFunc = Context.getTypeDeclType(cast<TypeDecl>(TD))->isFunctionType(); |
| } |
| |
| bool isInstField = (DS.getStorageClassSpec() == DeclSpec::SCS_unspecified && |
| !isFunc); |
| |
| Decl *Member; |
| bool InvalidDecl = false; |
| |
| if (isInstField) |
| Member = static_cast<Decl*>(ActOnField(S, Loc, D, BitWidth)); |
| else |
| Member = static_cast<Decl*>(ActOnDeclarator(S, D, LastInGroup)); |
| |
| if (!Member) return LastInGroup; |
| |
| assert((II || isInstField) && "No identifier for non-field ?"); |
| |
| // set/getAccess is not part of Decl's interface to avoid bloating it with C++ |
| // specific methods. Use a wrapper class that can be used with all C++ class |
| // member decls. |
| CXXClassMemberWrapper(Member).setAccess(AS); |
| |
| if (BitWidth) { |
| // C++ 9.6p2: Only when declaring an unnamed bit-field may the |
| // constant-expression be a value equal to zero. |
| // FIXME: Check this. |
| |
| if (D.isFunctionDeclarator()) { |
| // FIXME: Emit diagnostic about only constructors taking base initializers |
| // or something similar, when constructor support is in place. |
| Diag(Loc, diag::err_not_bitfield_type, |
| II->getName(), BitWidth->getSourceRange()); |
| InvalidDecl = true; |
| |
| } else if (isInstField) { |
| // C++ 9.6p3: A bit-field shall have integral or enumeration type. |
| if (!cast<FieldDecl>(Member)->getType()->isIntegralType()) { |
| Diag(Loc, diag::err_not_integral_type_bitfield, |
| II->getName(), BitWidth->getSourceRange()); |
| InvalidDecl = true; |
| } |
| |
| } else if (isa<FunctionDecl>(Member)) { |
| // A function typedef ("typedef int f(); f a;"). |
| // C++ 9.6p3: A bit-field shall have integral or enumeration type. |
| Diag(Loc, diag::err_not_integral_type_bitfield, |
| II->getName(), BitWidth->getSourceRange()); |
| InvalidDecl = true; |
| |
| } else if (isa<TypedefDecl>(Member)) { |
| // "cannot declare 'A' to be a bit-field type" |
| Diag(Loc, diag::err_not_bitfield_type, II->getName(), |
| BitWidth->getSourceRange()); |
| InvalidDecl = true; |
| |
| } else { |
| assert(isa<CXXClassVarDecl>(Member) && |
| "Didn't we cover all member kinds?"); |
| // C++ 9.6p3: A bit-field shall not be a static member. |
| // "static member 'A' cannot be a bit-field" |
| Diag(Loc, diag::err_static_not_bitfield, II->getName(), |
| BitWidth->getSourceRange()); |
| InvalidDecl = true; |
| } |
| } |
| |
| if (Init) { |
| // C++ 9.2p4: A member-declarator can contain a constant-initializer only |
| // if it declares a static member of const integral or const enumeration |
| // type. |
| if (CXXClassVarDecl *CVD = dyn_cast<CXXClassVarDecl>(Member)) { |
| // ...static member of... |
| CVD->setInit(Init); |
| // ...const integral or const enumeration type. |
| if (Context.getCanonicalType(CVD->getType()).isConstQualified() && |
| CVD->getType()->isIntegralType()) { |
| // constant-initializer |
| if (CheckForConstantInitializer(Init, CVD->getType())) |
| InvalidDecl = true; |
| |
| } else { |
| // not const integral. |
| Diag(Loc, diag::err_member_initialization, |
| II->getName(), Init->getSourceRange()); |
| InvalidDecl = true; |
| } |
| |
| } else { |
| // not static member. |
| Diag(Loc, diag::err_member_initialization, |
| II->getName(), Init->getSourceRange()); |
| InvalidDecl = true; |
| } |
| } |
| |
| if (InvalidDecl) |
| Member->setInvalidDecl(); |
| |
| if (isInstField) { |
| FieldCollector->Add(cast<CXXFieldDecl>(Member)); |
| return LastInGroup; |
| } |
| return Member; |
| } |
| |
| void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc, |
| DeclTy *TagDecl, |
| SourceLocation LBrac, |
| SourceLocation RBrac) { |
| ActOnFields(S, RLoc, TagDecl, |
| (DeclTy**)FieldCollector->getCurFields(), |
| FieldCollector->getCurNumFields(), LBrac, RBrac, 0); |
| } |
| |
| /// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared |
| /// special functions, such as the default constructor, copy |
| /// constructor, or destructor, to the given C++ class (C++ |
| /// [special]p1). This routine can only be executed just before the |
| /// definition of the class is complete. |
| void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) { |
| if (!ClassDecl->hasUserDeclaredConstructor()) { |
| // C++ [class.ctor]p5: |
| // A default constructor for a class X is a constructor of class X |
| // that can be called without an argument. If there is no |
| // user-declared constructor for class X, a default constructor is |
| // implicitly declared. An implicitly-declared default constructor |
| // is an inline public member of its class. |
| CXXConstructorDecl *DefaultCon = |
| CXXConstructorDecl::Create(Context, ClassDecl, |
| ClassDecl->getLocation(), |
| ClassDecl->getIdentifier(), |
| Context.getFunctionType(Context.VoidTy, |
| 0, 0, false, 0), |
| /*isExplicit=*/false, |
| /*isInline=*/true, |
| /*isImplicitlyDeclared=*/true); |
| DefaultCon->setAccess(AS_public); |
| ClassDecl->addConstructor(Context, DefaultCon); |
| } |
| |
| if (!ClassDecl->hasUserDeclaredCopyConstructor()) { |
| // C++ [class.copy]p4: |
| // If the class definition does not explicitly declare a copy |
| // constructor, one is declared implicitly. |
| |
| // C++ [class.copy]p5: |
| // The implicitly-declared copy constructor for a class X will |
| // have the form |
| // |
| // X::X(const X&) |
| // |
| // if |
| bool HasConstCopyConstructor = true; |
| |
| // -- each direct or virtual base class B of X has a copy |
| // constructor whose first parameter is of type const B& or |
| // const volatile B&, and |
| for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); |
| HasConstCopyConstructor && Base != ClassDecl->bases_end(); ++Base) { |
| const CXXRecordDecl *BaseClassDecl |
| = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); |
| HasConstCopyConstructor |
| = BaseClassDecl->hasConstCopyConstructor(Context); |
| } |
| |
| // -- for all the nonstatic data members of X that are of a |
| // class type M (or array thereof), each such class type |
| // has a copy constructor whose first parameter is of type |
| // const M& or const volatile M&. |
| for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(); |
| HasConstCopyConstructor && Field != ClassDecl->field_end(); ++Field) { |
| QualType FieldType = (*Field)->getType(); |
| if (const ArrayType *Array = Context.getAsArrayType(FieldType)) |
| FieldType = Array->getElementType(); |
| if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { |
| const CXXRecordDecl *FieldClassDecl |
| = cast<CXXRecordDecl>(FieldClassType->getDecl()); |
| HasConstCopyConstructor |
| = FieldClassDecl->hasConstCopyConstructor(Context); |
| } |
| } |
| |
| // Otherwise, the implicitly declared copy constructor will have |
| // the form |
| // |
| // X::X(X&) |
| QualType ArgType = Context.getTypeDeclType(ClassDecl); |
| if (HasConstCopyConstructor) |
| ArgType = ArgType.withConst(); |
| ArgType = Context.getReferenceType(ArgType); |
| |
| // An implicitly-declared copy constructor is an inline public |
| // member of its class. |
| CXXConstructorDecl *CopyConstructor |
| = CXXConstructorDecl::Create(Context, ClassDecl, |
| ClassDecl->getLocation(), |
| ClassDecl->getIdentifier(), |
| Context.getFunctionType(Context.VoidTy, |
| &ArgType, 1, |
| false, 0), |
| /*isExplicit=*/false, |
| /*isInline=*/true, |
| /*isImplicitlyDeclared=*/true); |
| CopyConstructor->setAccess(AS_public); |
| |
| // Add the parameter to the constructor. |
| ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor, |
| ClassDecl->getLocation(), |
| /*IdentifierInfo=*/0, |
| ArgType, VarDecl::None, 0, 0); |
| CopyConstructor->setParams(&FromParam, 1); |
| |
| ClassDecl->addConstructor(Context, CopyConstructor); |
| } |
| |
| // FIXME: Implicit destructor |
| // FIXME: Implicit copy assignment operator |
| } |
| |
| void Sema::ActOnFinishCXXClassDef(DeclTy *D) { |
| CXXRecordDecl *Rec = cast<CXXRecordDecl>(static_cast<Decl *>(D)); |
| FieldCollector->FinishClass(); |
| AddImplicitlyDeclaredMembersToClass(Rec); |
| PopDeclContext(); |
| |
| // Everything, including inline method definitions, have been parsed. |
| // Let the consumer know of the new TagDecl definition. |
| Consumer.HandleTagDeclDefinition(Rec); |
| } |
| |
| /// ActOnConstructorDeclarator - Called by ActOnDeclarator to complete |
| /// the declaration of the given C++ constructor ConDecl that was |
| /// built from declarator D. This routine is responsible for checking |
| /// that the newly-created constructor declaration is well-formed and |
| /// for recording it in the C++ class. Example: |
| /// |
| /// @code |
| /// class X { |
| /// X(); // X::X() will be the ConDecl. |
| /// }; |
| /// @endcode |
| Sema::DeclTy *Sema::ActOnConstructorDeclarator(CXXConstructorDecl *ConDecl) { |
| assert(ConDecl && "Expected to receive a constructor declaration"); |
| |
| // Check default arguments on the constructor |
| CheckCXXDefaultArguments(ConDecl); |
| |
| CXXRecordDecl *ClassDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); |
| if (!ClassDecl) { |
| ConDecl->setInvalidDecl(); |
| return ConDecl; |
| } |
| |
| // Make sure this constructor is an overload of the existing |
| // constructors. |
| OverloadedFunctionDecl::function_iterator MatchedDecl; |
| if (!IsOverload(ConDecl, ClassDecl->getConstructors(), MatchedDecl)) { |
| Diag(ConDecl->getLocation(), |
| diag::err_constructor_redeclared, |
| SourceRange(ConDecl->getLocation())); |
| Diag((*MatchedDecl)->getLocation(), |
| diag::err_previous_declaration, |
| SourceRange((*MatchedDecl)->getLocation())); |
| ConDecl->setInvalidDecl(); |
| return ConDecl; |
| } |
| |
| |
| // C++ [class.copy]p3: |
| // A declaration of a constructor for a class X is ill-formed if |
| // its first parameter is of type (optionally cv-qualified) X and |
| // either there are no other parameters or else all other |
| // parameters have default arguments. |
| if ((ConDecl->getNumParams() == 1) || |
| (ConDecl->getNumParams() > 1 && |
| ConDecl->getParamDecl(1)->getDefaultArg() != 0)) { |
| QualType ParamType = ConDecl->getParamDecl(0)->getType(); |
| QualType ClassTy = Context.getTagDeclType( |
| const_cast<CXXRecordDecl*>(ConDecl->getParent())); |
| if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) { |
| Diag(ConDecl->getLocation(), |
| diag::err_constructor_byvalue_arg, |
| SourceRange(ConDecl->getParamDecl(0)->getLocation())); |
| ConDecl->setInvalidDecl(); |
| return 0; |
| } |
| } |
| |
| // Add this constructor to the set of constructors of the current |
| // class. |
| ClassDecl->addConstructor(Context, ConDecl); |
| |
| return (DeclTy *)ConDecl; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Namespace Handling |
| //===----------------------------------------------------------------------===// |
| |
| /// ActOnStartNamespaceDef - This is called at the start of a namespace |
| /// definition. |
| Sema::DeclTy *Sema::ActOnStartNamespaceDef(Scope *NamespcScope, |
| SourceLocation IdentLoc, |
| IdentifierInfo *II, |
| SourceLocation LBrace) { |
| NamespaceDecl *Namespc = |
| NamespaceDecl::Create(Context, CurContext, IdentLoc, II); |
| Namespc->setLBracLoc(LBrace); |
| |
| Scope *DeclRegionScope = NamespcScope->getParent(); |
| |
| if (II) { |
| // C++ [namespace.def]p2: |
| // The identifier in an original-namespace-definition shall not have been |
| // previously defined in the declarative region in which the |
| // original-namespace-definition appears. The identifier in an |
| // original-namespace-definition is the name of the namespace. Subsequently |
| // in that declarative region, it is treated as an original-namespace-name. |
| |
| Decl *PrevDecl = |
| LookupDecl(II, Decl::IDNS_Tag | Decl::IDNS_Ordinary, DeclRegionScope, |
| /*enableLazyBuiltinCreation=*/false); |
| |
| if (PrevDecl && isDeclInScope(PrevDecl, CurContext, DeclRegionScope)) { |
| if (NamespaceDecl *OrigNS = dyn_cast<NamespaceDecl>(PrevDecl)) { |
| // This is an extended namespace definition. |
| // Attach this namespace decl to the chain of extended namespace |
| // definitions. |
| NamespaceDecl *NextNS = OrigNS; |
| while (NextNS->getNextNamespace()) |
| NextNS = NextNS->getNextNamespace(); |
| |
| NextNS->setNextNamespace(Namespc); |
| Namespc->setOriginalNamespace(OrigNS); |
| |
| // We won't add this decl to the current scope. We want the namespace |
| // name to return the original namespace decl during a name lookup. |
| } else { |
| // This is an invalid name redefinition. |
| Diag(Namespc->getLocation(), diag::err_redefinition_different_kind, |
| Namespc->getName()); |
| Diag(PrevDecl->getLocation(), diag::err_previous_definition); |
| Namespc->setInvalidDecl(); |
| // Continue on to push Namespc as current DeclContext and return it. |
| } |
| } else { |
| // This namespace name is declared for the first time. |
| PushOnScopeChains(Namespc, DeclRegionScope); |
| } |
| } |
| else { |
| // FIXME: Handle anonymous namespaces |
| } |
| |
| // Although we could have an invalid decl (i.e. the namespace name is a |
| // redefinition), push it as current DeclContext and try to continue parsing. |
| PushDeclContext(Namespc->getOriginalNamespace()); |
| return Namespc; |
| } |
| |
| /// ActOnFinishNamespaceDef - This callback is called after a namespace is |
| /// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef. |
| void Sema::ActOnFinishNamespaceDef(DeclTy *D, SourceLocation RBrace) { |
| Decl *Dcl = static_cast<Decl *>(D); |
| NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl); |
| assert(Namespc && "Invalid parameter, expected NamespaceDecl"); |
| Namespc->setRBracLoc(RBrace); |
| PopDeclContext(); |
| } |
| |
| |
| /// AddCXXDirectInitializerToDecl - This action is called immediately after |
| /// ActOnDeclarator, when a C++ direct initializer is present. |
| /// e.g: "int x(1);" |
| void Sema::AddCXXDirectInitializerToDecl(DeclTy *Dcl, SourceLocation LParenLoc, |
| ExprTy **ExprTys, unsigned NumExprs, |
| SourceLocation *CommaLocs, |
| SourceLocation RParenLoc) { |
| assert(NumExprs != 0 && ExprTys && "missing expressions"); |
| Decl *RealDecl = static_cast<Decl *>(Dcl); |
| |
| // If there is no declaration, there was an error parsing it. Just ignore |
| // the initializer. |
| if (RealDecl == 0) { |
| for (unsigned i = 0; i != NumExprs; ++i) |
| delete static_cast<Expr *>(ExprTys[i]); |
| return; |
| } |
| |
| VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); |
| if (!VDecl) { |
| Diag(RealDecl->getLocation(), diag::err_illegal_initializer); |
| RealDecl->setInvalidDecl(); |
| return; |
| } |
| |
| // We will treat direct-initialization as a copy-initialization: |
| // int x(1); -as-> int x = 1; |
| // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); |
| // |
| // Clients that want to distinguish between the two forms, can check for |
| // direct initializer using VarDecl::hasCXXDirectInitializer(). |
| // A major benefit is that clients that don't particularly care about which |
| // exactly form was it (like the CodeGen) can handle both cases without |
| // special case code. |
| |
| // C++ 8.5p11: |
| // The form of initialization (using parentheses or '=') is generally |
| // insignificant, but does matter when the entity being initialized has a |
| // class type. |
| |
| if (VDecl->getType()->isRecordType()) { |
| // FIXME: When constructors for class types are supported, determine how |
| // exactly semantic checking will be done for direct initializers. |
| unsigned DiagID = PP.getDiagnostics().getCustomDiagID(Diagnostic::Error, |
| "initialization for class types is not handled yet"); |
| Diag(VDecl->getLocation(), DiagID); |
| RealDecl->setInvalidDecl(); |
| return; |
| } |
| |
| if (NumExprs > 1) { |
| Diag(CommaLocs[0], diag::err_builtin_direct_init_more_than_one_arg, |
| SourceRange(VDecl->getLocation(), RParenLoc)); |
| RealDecl->setInvalidDecl(); |
| return; |
| } |
| |
| // Let clients know that initialization was done with a direct initializer. |
| VDecl->setCXXDirectInitializer(true); |
| |
| assert(NumExprs == 1 && "Expected 1 expression"); |
| // Set the init expression, handles conversions. |
| AddInitializerToDecl(Dcl, ExprTys[0]); |
| } |
| |
| /// CompareReferenceRelationship - Compare the two types T1 and T2 to |
| /// determine whether they are reference-related, |
| /// reference-compatible, reference-compatible with added |
| /// qualification, or incompatible, for use in C++ initialization by |
| /// reference (C++ [dcl.ref.init]p4). Neither type can be a reference |
| /// type, and the first type (T1) is the pointee type of the reference |
| /// type being initialized. |
| Sema::ReferenceCompareResult |
| Sema::CompareReferenceRelationship(QualType T1, QualType T2, |
| bool& DerivedToBase) { |
| assert(!T1->isReferenceType() && "T1 must be the pointee type of the reference type"); |
| assert(!T2->isReferenceType() && "T2 cannot be a reference type"); |
| |
| T1 = Context.getCanonicalType(T1); |
| T2 = Context.getCanonicalType(T2); |
| QualType UnqualT1 = T1.getUnqualifiedType(); |
| QualType UnqualT2 = T2.getUnqualifiedType(); |
| |
| // C++ [dcl.init.ref]p4: |
| // Given types “cv1 T1” and “cv2 T2,” “cv1 T1” is |
| // reference-related to “cv2 T2” if T1 is the same type as T2, or |
| // T1 is a base class of T2. |
| if (UnqualT1 == UnqualT2) |
| DerivedToBase = false; |
| else if (IsDerivedFrom(UnqualT2, UnqualT1)) |
| DerivedToBase = true; |
| else |
| return Ref_Incompatible; |
| |
| // At this point, we know that T1 and T2 are reference-related (at |
| // least). |
| |
| // C++ [dcl.init.ref]p4: |
| // "cv1 T1” is reference-compatible with “cv2 T2” if T1 is |
| // reference-related to T2 and cv1 is the same cv-qualification |
| // as, or greater cv-qualification than, cv2. For purposes of |
| // overload resolution, cases for which cv1 is greater |
| // cv-qualification than cv2 are identified as |
| // reference-compatible with added qualification (see 13.3.3.2). |
| if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) |
| return Ref_Compatible; |
| else if (T1.isMoreQualifiedThan(T2)) |
| return Ref_Compatible_With_Added_Qualification; |
| else |
| return Ref_Related; |
| } |
| |
| /// CheckReferenceInit - Check the initialization of a reference |
| /// variable with the given initializer (C++ [dcl.init.ref]). Init is |
| /// the initializer (either a simple initializer or an initializer |
| /// list), and DeclType is the type of the declaration. When ICS is |
| /// non-null, this routine will compute the implicit conversion |
| /// sequence according to C++ [over.ics.ref] and will not produce any |
| /// diagnostics; when ICS is null, it will emit diagnostics when any |
| /// errors are found. Either way, a return value of true indicates |
| /// that there was a failure, a return value of false indicates that |
| /// the reference initialization succeeded. |
| bool |
| Sema::CheckReferenceInit(Expr *&Init, QualType &DeclType, |
| ImplicitConversionSequence *ICS) { |
| assert(DeclType->isReferenceType() && "Reference init needs a reference"); |
| |
| QualType T1 = DeclType->getAsReferenceType()->getPointeeType(); |
| QualType T2 = Init->getType(); |
| |
| // Compute some basic properties of the types and the initializer. |
| bool DerivedToBase = false; |
| Expr::isLvalueResult InitLvalue = Init->isLvalue(Context); |
| ReferenceCompareResult RefRelationship |
| = CompareReferenceRelationship(T1, T2, DerivedToBase); |
| |
| // Most paths end in a failed conversion. |
| if (ICS) |
| ICS->ConversionKind = ImplicitConversionSequence::BadConversion; |
| |
| // C++ [dcl.init.ref]p5: |
| // A reference to type “cv1 T1” is initialized by an expression |
| // of type “cv2 T2” as follows: |
| |
| // -- If the initializer expression |
| |
| bool BindsDirectly = false; |
| // -- is an lvalue (but is not a bit-field), and “cv1 T1” is |
| // reference-compatible with “cv2 T2,” or |
| // |
| // Note that the bit-field check is skipped if we are just computing |
| // the implicit conversion sequence (C++ [over.best.ics]p2). |
| if (InitLvalue == Expr::LV_Valid && (ICS || !Init->isBitField()) && |
| RefRelationship >= Ref_Compatible_With_Added_Qualification) { |
| BindsDirectly = true; |
| |
| if (ICS) { |
| // C++ [over.ics.ref]p1: |
| // When a parameter of reference type binds directly (8.5.3) |
| // to an argument expression, the implicit conversion sequence |
| // is the identity conversion, unless the argument expression |
| // has a type that is a derived class of the parameter type, |
| // in which case the implicit conversion sequence is a |
| // derived-to-base Conversion (13.3.3.1). |
| ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; |
| ICS->Standard.First = ICK_Identity; |
| ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; |
| ICS->Standard.Third = ICK_Identity; |
| ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); |
| ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); |
| ICS->Standard.ReferenceBinding = true; |
| ICS->Standard.DirectBinding = true; |
| |
| // Nothing more to do: the inaccessibility/ambiguity check for |
| // derived-to-base conversions is suppressed when we're |
| // computing the implicit conversion sequence (C++ |
| // [over.best.ics]p2). |
| return false; |
| } else { |
| // Perform the conversion. |
| // FIXME: Binding to a subobject of the lvalue is going to require |
| // more AST annotation than this. |
| ImpCastExprToType(Init, T1); |
| } |
| } |
| |
| // -- has a class type (i.e., T2 is a class type) and can be |
| // implicitly converted to an lvalue of type “cv3 T3,” |
| // where “cv1 T1” is reference-compatible with “cv3 T3” |
| // 92) (this conversion is selected by enumerating the |
| // applicable conversion functions (13.3.1.6) and choosing |
| // the best one through overload resolution (13.3)), |
| // FIXME: Implement this second bullet, once we have conversion |
| // functions. Also remember C++ [over.ics.ref]p1, second part. |
| |
| if (BindsDirectly) { |
| // C++ [dcl.init.ref]p4: |
| // [...] In all cases where the reference-related or |
| // reference-compatible relationship of two types is used to |
| // establish the validity of a reference binding, and T1 is a |
| // base class of T2, a program that necessitates such a binding |
| // is ill-formed if T1 is an inaccessible (clause 11) or |
| // ambiguous (10.2) base class of T2. |
| // |
| // Note that we only check this condition when we're allowed to |
| // complain about errors, because we should not be checking for |
| // ambiguity (or inaccessibility) unless the reference binding |
| // actually happens. |
| if (DerivedToBase) |
| return CheckDerivedToBaseConversion(T2, T1, |
| Init->getSourceRange().getBegin(), |
| Init->getSourceRange()); |
| else |
| return false; |
| } |
| |
| // -- Otherwise, the reference shall be to a non-volatile const |
| // type (i.e., cv1 shall be const). |
| if (T1.getCVRQualifiers() != QualType::Const) { |
| if (!ICS) |
| Diag(Init->getSourceRange().getBegin(), |
| diag::err_not_reference_to_const_init, |
| T1.getAsString(), |
| InitLvalue != Expr::LV_Valid? "temporary" : "value", |
| T2.getAsString(), Init->getSourceRange()); |
| return true; |
| } |
| |
| // -- If the initializer expression is an rvalue, with T2 a |
| // class type, and “cv1 T1” is reference-compatible with |
| // “cv2 T2,” the reference is bound in one of the |
| // following ways (the choice is implementation-defined): |
| // |
| // -- The reference is bound to the object represented by |
| // the rvalue (see 3.10) or to a sub-object within that |
| // object. |
| // |
| // -- A temporary of type “cv1 T2” [sic] is created, and |
| // a constructor is called to copy the entire rvalue |
| // object into the temporary. The reference is bound to |
| // the temporary or to a sub-object within the |
| // temporary. |
| // |
| // |
| // The constructor that would be used to make the copy |
| // shall be callable whether or not the copy is actually |
| // done. |
| // |
| // Note that C++0x [dcl.ref.init]p5 takes away this implementation |
| // freedom, so we will always take the first option and never build |
| // a temporary in this case. FIXME: We will, however, have to check |
| // for the presence of a copy constructor in C++98/03 mode. |
| if (InitLvalue != Expr::LV_Valid && T2->isRecordType() && |
| RefRelationship >= Ref_Compatible_With_Added_Qualification) { |
| if (ICS) { |
| ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; |
| ICS->Standard.First = ICK_Identity; |
| ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; |
| ICS->Standard.Third = ICK_Identity; |
| ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); |
| ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); |
| ICS->Standard.ReferenceBinding = true; |
| ICS->Standard.DirectBinding = false; |
| } else { |
| // FIXME: Binding to a subobject of the rvalue is going to require |
| // more AST annotation than this. |
| ImpCastExprToType(Init, T1); |
| } |
| return false; |
| } |
| |
| // -- 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. 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. |
| if (RefRelationship == Ref_Related) { |
| // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then |
| // we would be reference-compatible or reference-compatible with |
| // added qualification. But that wasn't the case, so the reference |
| // initialization fails. |
| if (!ICS) |
| Diag(Init->getSourceRange().getBegin(), |
| diag::err_reference_init_drops_quals, |
| T1.getAsString(), |
| InitLvalue != Expr::LV_Valid? "temporary" : "value", |
| T2.getAsString(), Init->getSourceRange()); |
| return true; |
| } |
| |
| // Actually try to convert the initializer to T1. |
| if (ICS) { |
| /// C++ [over.ics.ref]p2: |
| /// |
| /// When a parameter of reference type is not bound directly to |
| /// an argument expression, the conversion sequence is the one |
| /// required to convert the argument expression to the |
| /// underlying type of the reference according to |
| /// 13.3.3.1. Conceptually, this conversion sequence corresponds |
| /// to copy-initializing a temporary of the underlying type with |
| /// the argument expression. Any difference in top-level |
| /// cv-qualification is subsumed by the initialization itself |
| /// and does not constitute a conversion. |
| *ICS = TryImplicitConversion(Init, T1); |
| return ICS->ConversionKind == ImplicitConversionSequence::BadConversion; |
| } else { |
| return PerformImplicitConversion(Init, T1); |
| } |
| } |