Пример #1
0
/// @brief Ensure that the type T is a complete type. 
///
/// This routine checks whether the type @p T is complete in any
/// context where a complete type is required. If @p T is a complete
/// type, returns false. If @p T is a class template specialization,
/// this routine then attempts to perform class template
/// instantiation. If instantiation fails, or if @p T is incomplete
/// and cannot be completed, issues the diagnostic @p diag (giving it
/// the type @p T) and returns true.
///
/// @param Loc  The location in the source that the incomplete type
/// diagnostic should refer to.
///
/// @param T  The type that this routine is examining for completeness.
///
/// @param diag The diagnostic value (e.g., 
/// @c diag::err_typecheck_decl_incomplete_type) that will be used
/// for the error message if @p T is incomplete.
///
/// @param Range1  An optional range in the source code that will be a
/// part of the "incomplete type" error message.
///
/// @param Range2  An optional range in the source code that will be a
/// part of the "incomplete type" error message.
///
/// @param PrintType If non-NULL, the type that should be printed
/// instead of @p T. This parameter should be used when the type that
/// we're checking for incompleteness isn't the type that should be
/// displayed to the user, e.g., when T is a type and PrintType is a
/// pointer to T.
///
/// @returns @c true if @p T is incomplete and a diagnostic was emitted,
/// @c false otherwise.
bool Sema::RequireCompleteType(SourceLocation Loc, QualType T, unsigned diag,
                                  SourceRange Range1, SourceRange Range2,
                                  QualType PrintType) {
  // If we have a complete type, we're done.
  if (!T->isIncompleteType())
    return false;

  // If we have a class template specialization or a class member of a
  // class template specialization, try to instantiate it.
  if (const RecordType *Record = T->getAsRecordType()) {
    if (ClassTemplateSpecializationDecl *ClassTemplateSpec
          = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) {
      if (ClassTemplateSpec->getSpecializationKind() == TSK_Undeclared) {
        // Update the class template specialization's location to
        // refer to the point of instantiation.
        if (Loc.isValid())
          ClassTemplateSpec->setLocation(Loc);
        return InstantiateClassTemplateSpecialization(ClassTemplateSpec,
                                             /*ExplicitInstantiation=*/false);
      }
    } else if (CXXRecordDecl *Rec 
                 = dyn_cast<CXXRecordDecl>(Record->getDecl())) {
      if (CXXRecordDecl *Pattern = Rec->getInstantiatedFromMemberClass()) {
        // Find the class template specialization that surrounds this
        // member class.
        ClassTemplateSpecializationDecl *Spec = 0;
        for (DeclContext *Parent = Rec->getDeclContext(); 
             Parent && !Spec; Parent = Parent->getParent())
          Spec = dyn_cast<ClassTemplateSpecializationDecl>(Parent);
        assert(Spec && "Not a member of a class template specialization?");
        return InstantiateClass(Loc, Rec, Pattern,
                                Spec->getTemplateArgs(), 
                                Spec->getNumTemplateArgs());
      }
    }
  }

  if (PrintType.isNull())
    PrintType = T;

  // We have an incomplete type. Produce a diagnostic.
  Diag(Loc, diag) << PrintType << Range1 << Range2;

  // If the type was a forward declaration of a class/struct/union
  // type, produce 
  const TagType *Tag = 0;
  if (const RecordType *Record = T->getAsRecordType())
    Tag = Record;
  else if (const EnumType *Enum = T->getAsEnumType())
    Tag = Enum;

  if (Tag && !Tag->getDecl()->isInvalidDecl())
    Diag(Tag->getDecl()->getLocation(), 
         Tag->isBeingDefined() ? diag::note_type_being_defined
                               : diag::note_forward_declaration)
        << QualType(Tag, 0);

  return true;
}
Пример #2
0
/// FindAllocationFunctions - Finds the overloads of operator new and delete
/// that are appropriate for the allocation.
bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
                                   bool UseGlobal, QualType AllocType,
                                   bool IsArray, Expr **PlaceArgs,
                                   unsigned NumPlaceArgs,
                                   FunctionDecl *&OperatorNew,
                                   FunctionDecl *&OperatorDelete)
{
  // --- Choosing an allocation function ---
  // C++ 5.3.4p8 - 14 & 18
  // 1) If UseGlobal is true, only look in the global scope. Else, also look
  //   in the scope of the allocated class.
  // 2) If an array size is given, look for operator new[], else look for
  //   operator new.
  // 3) The first argument is always size_t. Append the arguments from the
  //   placement form.
  // FIXME: Also find the appropriate delete operator.

  llvm::SmallVector<Expr*, 8> AllocArgs(1 + NumPlaceArgs);
  // We don't care about the actual value of this argument.
  // FIXME: Should the Sema create the expression and embed it in the syntax
  // tree? Or should the consumer just recalculate the value?
  AllocArgs[0] = new (Context) IntegerLiteral(llvm::APInt::getNullValue(
                                        Context.Target.getPointerWidth(0)),
                                    Context.getSizeType(),
                                    SourceLocation());
  std::copy(PlaceArgs, PlaceArgs + NumPlaceArgs, AllocArgs.begin() + 1);

  DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName(
                                        IsArray ? OO_Array_New : OO_New);
  if (AllocType->isRecordType() && !UseGlobal) {
    CXXRecordDecl *Record 
      = cast<CXXRecordDecl>(AllocType->getAsRecordType()->getDecl());
    // FIXME: We fail to find inherited overloads.
    if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0],
                          AllocArgs.size(), Record, /*AllowMissing=*/true,
                          OperatorNew))
      return true;
  }
  if (!OperatorNew) {
    // Didn't find a member overload. Look for a global one.
    DeclareGlobalNewDelete();
    DeclContext *TUDecl = Context.getTranslationUnitDecl();
    if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0],
                          AllocArgs.size(), TUDecl, /*AllowMissing=*/false,
                          OperatorNew))
      return true;
  }

  // FIXME: This is leaked on error. But so much is currently in Sema that it's
  // easier to clean it in one go.
  AllocArgs[0]->Destroy(Context);
  return false;
}
Пример #3
0
/// ActOnCXXConditionDeclarationExpr - Parsed a condition declaration of a
/// C++ if/switch/while/for statement.
/// e.g: "if (int x = f()) {...}"
Action::OwningExprResult
Sema::ActOnCXXConditionDeclarationExpr(Scope *S, SourceLocation StartLoc,
                                       Declarator &D,
                                       SourceLocation EqualLoc,
                                       ExprArg AssignExprVal) {
  assert(AssignExprVal.get() && "Null assignment expression");

  // C++ 6.4p2:
  // The declarator shall not specify a function or an array.
  // The type-specifier-seq shall not contain typedef and shall not declare a
  // new class or enumeration.

  assert(D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef &&
         "Parser allowed 'typedef' as storage class of condition decl.");

  QualType Ty = GetTypeForDeclarator(D, S);
  
  if (Ty->isFunctionType()) { // The declarator shall not specify a function...
    // We exit without creating a CXXConditionDeclExpr because a FunctionDecl
    // would be created and CXXConditionDeclExpr wants a VarDecl.
    return ExprError(Diag(StartLoc, diag::err_invalid_use_of_function_type)
      << SourceRange(StartLoc, EqualLoc));
  } else if (Ty->isArrayType()) { // ...or an array.
    Diag(StartLoc, diag::err_invalid_use_of_array_type)
      << SourceRange(StartLoc, EqualLoc);
  } else if (const RecordType *RT = Ty->getAsRecordType()) {
    RecordDecl *RD = RT->getDecl();
    // The type-specifier-seq shall not declare a new class...
    if (RD->isDefinition() &&
        (RD->getIdentifier() == 0 || S->isDeclScope(DeclPtrTy::make(RD))))
      Diag(RD->getLocation(), diag::err_type_defined_in_condition);
  } else if (const EnumType *ET = Ty->getAsEnumType()) {
    EnumDecl *ED = ET->getDecl();
    // ...or enumeration.
    if (ED->isDefinition() &&
        (ED->getIdentifier() == 0 || S->isDeclScope(DeclPtrTy::make(ED))))
      Diag(ED->getLocation(), diag::err_type_defined_in_condition);
  }

  DeclPtrTy Dcl = ActOnDeclarator(S, D, DeclPtrTy());
  if (!Dcl)
    return ExprError();
  AddInitializerToDecl(Dcl, move(AssignExprVal));

  // Mark this variable as one that is declared within a conditional.
  // We know that the decl had to be a VarDecl because that is the only type of
  // decl that can be assigned and the grammar requires an '='.
  VarDecl *VD = cast<VarDecl>(Dcl.getAs<Decl>());
  VD->setDeclaredInCondition(true);
  return Owned(new (Context) CXXConditionDeclExpr(StartLoc, EqualLoc, VD));
}
Пример #4
0
/// ActOnCXXNew - Parsed a C++ 'new' expression (C++ 5.3.4), as in e.g.:
/// @code new (memory) int[size][4] @endcode
/// or
/// @code ::new Foo(23, "hello") @endcode
/// For the interpretation of this heap of arguments, consult the base version.
Action::OwningExprResult
Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
                  SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
                  SourceLocation PlacementRParen, bool ParenTypeId,
                  Declarator &D, SourceLocation ConstructorLParen,
                  MultiExprArg ConstructorArgs,
                  SourceLocation ConstructorRParen)
{
  Expr *ArraySize = 0;
  unsigned Skip = 0;
  // If the specified type is an array, unwrap it and save the expression.
  if (D.getNumTypeObjects() > 0 &&
      D.getTypeObject(0).Kind == DeclaratorChunk::Array) {
    DeclaratorChunk &Chunk = D.getTypeObject(0);
    if (Chunk.Arr.hasStatic)
      return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
        << D.getSourceRange());
    if (!Chunk.Arr.NumElts)
      return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
        << D.getSourceRange());
    ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
    Skip = 1;
  }

  QualType AllocType = GetTypeForDeclarator(D, /*Scope=*/0, Skip);
  if (D.getInvalidType())
    return ExprError();

  if (CheckAllocatedType(AllocType, D))
    return ExprError();

  QualType ResultType = AllocType->isDependentType()
                          ? Context.DependentTy
                          : Context.getPointerType(AllocType);

  // That every array dimension except the first is constant was already
  // checked by the type check above.

  // C++ 5.3.4p6: "The expression in a direct-new-declarator shall have integral
  //   or enumeration type with a non-negative value."
  if (ArraySize && !ArraySize->isTypeDependent()) {
    QualType SizeType = ArraySize->getType();
    if (!SizeType->isIntegralType() && !SizeType->isEnumeralType())
      return ExprError(Diag(ArraySize->getSourceRange().getBegin(),
                            diag::err_array_size_not_integral)
        << SizeType << ArraySize->getSourceRange());
    // Let's see if this is a constant < 0. If so, we reject it out of hand.
    // We don't care about special rules, so we tell the machinery it's not
    // evaluated - it gives us a result in more cases.
    if (!ArraySize->isValueDependent()) {
      llvm::APSInt Value;
      if (ArraySize->isIntegerConstantExpr(Value, Context, 0, false)) {
        if (Value < llvm::APSInt(
                        llvm::APInt::getNullValue(Value.getBitWidth()), false))
          return ExprError(Diag(ArraySize->getSourceRange().getBegin(),
                           diag::err_typecheck_negative_array_size)
            << ArraySize->getSourceRange());
      }
    }
  }

  FunctionDecl *OperatorNew = 0;
  FunctionDecl *OperatorDelete = 0;
  Expr **PlaceArgs = (Expr**)PlacementArgs.get();
  unsigned NumPlaceArgs = PlacementArgs.size();
  if (!AllocType->isDependentType() &&
      !Expr::hasAnyTypeDependentArguments(PlaceArgs, NumPlaceArgs) &&
      FindAllocationFunctions(StartLoc,
                              SourceRange(PlacementLParen, PlacementRParen),
                              UseGlobal, AllocType, ArraySize, PlaceArgs,
                              NumPlaceArgs, OperatorNew, OperatorDelete))
    return ExprError();

  bool Init = ConstructorLParen.isValid();
  // --- Choosing a constructor ---
  // C++ 5.3.4p15
  // 1) If T is a POD and there's no initializer (ConstructorLParen is invalid)
  //   the object is not initialized. If the object, or any part of it, is
  //   const-qualified, it's an error.
  // 2) If T is a POD and there's an empty initializer, the object is value-
  //   initialized.
  // 3) If T is a POD and there's one initializer argument, the object is copy-
  //   constructed.
  // 4) If T is a POD and there's more initializer arguments, it's an error.
  // 5) If T is not a POD, the initializer arguments are used as constructor
  //   arguments.
  //
  // Or by the C++0x formulation:
  // 1) If there's no initializer, the object is default-initialized according
  //    to C++0x rules.
  // 2) Otherwise, the object is direct-initialized.
  CXXConstructorDecl *Constructor = 0;
  Expr **ConsArgs = (Expr**)ConstructorArgs.get();
  unsigned NumConsArgs = ConstructorArgs.size();
  if (AllocType->isDependentType()) {
    // Skip all the checks.
  }
  // FIXME: Should check for primitive/aggregate here, not record.
  else if (const RecordType *RT = AllocType->getAsRecordType()) {
    // FIXME: This is incorrect for when there is an empty initializer and
    // no user-defined constructor. Must zero-initialize, not default-construct.
    Constructor = PerformInitializationByConstructor(
                      AllocType, ConsArgs, NumConsArgs,
                      D.getSourceRange().getBegin(),
                      SourceRange(D.getSourceRange().getBegin(),
                                  ConstructorRParen),
                      RT->getDecl()->getDeclName(),
                      NumConsArgs != 0 ? IK_Direct : IK_Default);
    if (!Constructor)
      return ExprError();
  } else {
    if (!Init) {
      // FIXME: Check that no subpart is const.
      if (AllocType.isConstQualified())
        return ExprError(Diag(StartLoc, diag::err_new_uninitialized_const)
          << D.getSourceRange());
    } else if (NumConsArgs == 0) {
      // Object is value-initialized. Do nothing.
    } else if (NumConsArgs == 1) {
      // Object is direct-initialized.
      // FIXME: WHAT DeclarationName do we pass in here?
      if (CheckInitializerTypes(ConsArgs[0], AllocType, StartLoc,
                                DeclarationName() /*AllocType.getAsString()*/,
                                /*DirectInit=*/true))
        return ExprError();
    } else {
      return ExprError(Diag(StartLoc,
                            diag::err_builtin_direct_init_more_than_one_arg)
        << SourceRange(ConstructorLParen, ConstructorRParen));
    }
  }

  // FIXME: Also check that the destructor is accessible. (C++ 5.3.4p16)

  PlacementArgs.release();
  ConstructorArgs.release();
  return Owned(new (Context) CXXNewExpr(UseGlobal, OperatorNew, PlaceArgs,
                        NumPlaceArgs, ParenTypeId, ArraySize, Constructor, Init,
                        ConsArgs, NumConsArgs, OperatorDelete, ResultType,
                        StartLoc, Init ? ConstructorRParen : SourceLocation()));
}
Пример #5
0
/// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
/// Can be interpreted either as function-style casting ("int(x)")
/// or class type construction ("ClassType(x,y,z)")
/// or creation of a value-initialized type ("int()").
Action::OwningExprResult
Sema::ActOnCXXTypeConstructExpr(SourceRange TypeRange, TypeTy *TypeRep,
                                SourceLocation LParenLoc,
                                MultiExprArg exprs,
                                SourceLocation *CommaLocs,
                                SourceLocation RParenLoc) {
  assert(TypeRep && "Missing type!");
  QualType Ty = QualType::getFromOpaquePtr(TypeRep);
  unsigned NumExprs = exprs.size();
  Expr **Exprs = (Expr**)exprs.get();
  SourceLocation TyBeginLoc = TypeRange.getBegin();
  SourceRange FullRange = SourceRange(TyBeginLoc, RParenLoc);

  if (Ty->isDependentType() ||
      CallExpr::hasAnyTypeDependentArguments(Exprs, NumExprs)) {
    exprs.release();
    return Owned(new (Context) CXXTemporaryObjectExpr(0, Ty, TyBeginLoc,
                                                      Exprs, NumExprs,
                                                      RParenLoc));
  }


  // C++ [expr.type.conv]p1:
  // If the expression list is a single expression, the type conversion
  // expression is equivalent (in definedness, and if defined in meaning) to the
  // corresponding cast expression.
  //
  if (NumExprs == 1) {
    if (CheckCastTypes(TypeRange, Ty, Exprs[0]))
      return ExprError();
    exprs.release();
    return Owned(new (Context) CXXFunctionalCastExpr(Ty.getNonReferenceType(),
                                                     Ty, TyBeginLoc, Exprs[0],
                                                     RParenLoc));
  }

  if (const RecordType *RT = Ty->getAsRecordType()) {
    CXXRecordDecl *Record = cast<CXXRecordDecl>(RT->getDecl());

    if (NumExprs > 1 || Record->hasUserDeclaredConstructor()) {
      CXXConstructorDecl *Constructor
        = PerformInitializationByConstructor(Ty, Exprs, NumExprs,
                                             TypeRange.getBegin(),
                                             SourceRange(TypeRange.getBegin(),
                                                         RParenLoc),
                                             DeclarationName(),
                                             IK_Direct);

      if (!Constructor)
        return ExprError();

      exprs.release();
      return Owned(new (Context) CXXTemporaryObjectExpr(Constructor, Ty,
                                                        TyBeginLoc,  Exprs,
                                                        NumExprs, RParenLoc));
    }

    // Fall through to value-initialize an object of class type that
    // doesn't have a user-declared default constructor.
  }

  // C++ [expr.type.conv]p1:
  // If the expression list specifies more than a single value, the type shall
  // be a class with a suitably declared constructor.
  //
  if (NumExprs > 1)
    return ExprError(Diag(CommaLocs[0],
                          diag::err_builtin_func_cast_more_than_one_arg)
      << FullRange);

  assert(NumExprs == 0 && "Expected 0 expressions");

  // C++ [expr.type.conv]p2:
  // The expression T(), where T is a simple-type-specifier for a non-array
  // complete object type or the (possibly cv-qualified) void type, creates an
  // rvalue of the specified type, which is value-initialized.
  //
  if (Ty->isArrayType())
    return ExprError(Diag(TyBeginLoc,
                          diag::err_value_init_for_array_type) << FullRange);
  if (!Ty->isDependentType() && !Ty->isVoidType() &&
      RequireCompleteType(TyBeginLoc, Ty,
                          diag::err_invalid_incomplete_type_use, FullRange))
    return ExprError();

  if (RequireNonAbstractType(TyBeginLoc, Ty,
                             diag::err_allocation_of_abstract_type))
    return ExprError();
  
  exprs.release();
  return Owned(new (Context) CXXZeroInitValueExpr(Ty, TyBeginLoc, RParenLoc));
}
Пример #6
0
std::string DeclarationName::getAsString() const {
  switch (getNameKind()) {
  case Identifier:
    if (const IdentifierInfo *II = getAsIdentifierInfo())
      return II->getName();
    return "";

  case ObjCZeroArgSelector:
  case ObjCOneArgSelector:
  case ObjCMultiArgSelector:
    return getObjCSelector().getAsString();

  case CXXConstructorName: {
    QualType ClassType = getCXXNameType();
    if (const RecordType *ClassRec = ClassType->getAsRecordType())
      return ClassRec->getDecl()->getNameAsString();
    return ClassType.getAsString();
  }

  case CXXDestructorName: {
    std::string Result = "~";
    QualType Type = getCXXNameType();
    if (const RecordType *Rec = Type->getAsRecordType())
      Result += Rec->getDecl()->getNameAsString();
    else
      Result += Type.getAsString();
    return Result;
  }

  case CXXOperatorName: {
    static const char *OperatorNames[NUM_OVERLOADED_OPERATORS] = {
      0,
#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \
      Spelling,
#include "clang/Basic/OperatorKinds.def"
    };
    const char *OpName = OperatorNames[getCXXOverloadedOperator()];
    assert(OpName && "not an overloaded operator");
      
    std::string Result = "operator";
    if (OpName[0] >= 'a' && OpName[0] <= 'z')
      Result += ' ';
    Result += OpName;
    return Result;
  }

  case CXXConversionFunctionName: {
    std::string Result = "operator ";
    QualType Type = getCXXNameType();
    if (const RecordType *Rec = Type->getAsRecordType())
      Result += Rec->getDecl()->getNameAsString();
    else
      Result += Type.getAsString();
    return Result;
  }
  case CXXUsingDirective:
    return "<using-directive>";
  }

  assert(false && "Unexpected declaration name kind");
  return "";
}
Пример #7
0
/// \brief Build an array type.
///
/// \param T The type of each element in the array.
///
/// \param ASM C99 array size modifier (e.g., '*', 'static').
///  
/// \param ArraySize Expression describing the size of the array. 
///
/// \param Quals The cvr-qualifiers to be applied to the array's
/// element type.
///
/// \param Loc The location of the entity whose type involves this
/// array type or, if there is no such entity, the location of the
/// type that will have array type.
///
/// \param Entity The name of the entity that involves the array
/// type, if known.
///
/// \returns A suitable array type, if there are no errors. Otherwise,
/// returns a NULL type.
QualType Sema::BuildArrayType(QualType T, ArrayType::ArraySizeModifier ASM,
                              Expr *ArraySize, unsigned Quals,
                              SourceLocation Loc, DeclarationName Entity) {
  // C99 6.7.5.2p1: If the element type is an incomplete or function type, 
  // reject it (e.g. void ary[7], struct foo ary[7], void ary[7]())
  if (RequireCompleteType(Loc, T, 
                             diag::err_illegal_decl_array_incomplete_type))
    return QualType();

  if (T->isFunctionType()) {
    Diag(Loc, diag::err_illegal_decl_array_of_functions)
      << getPrintableNameForEntity(Entity);
    return QualType();
  }
    
  // C++ 8.3.2p4: There shall be no ... arrays of references ...
  if (T->isReferenceType()) {
    Diag(Loc, diag::err_illegal_decl_array_of_references)
      << getPrintableNameForEntity(Entity);
    return QualType();
  } 

  if (const RecordType *EltTy = T->getAsRecordType()) {
    // If the element type is a struct or union that contains a variadic
    // array, accept it as a GNU extension: C99 6.7.2.1p2.
    if (EltTy->getDecl()->hasFlexibleArrayMember())
      Diag(Loc, diag::ext_flexible_array_in_array) << T;
  } else if (T->isObjCInterfaceType()) {
    Diag(Loc, diag::warn_objc_array_of_interfaces) << T;
  }
      
  // C99 6.7.5.2p1: The size expression shall have integer type.
  if (ArraySize && !ArraySize->isTypeDependent() &&
      !ArraySize->getType()->isIntegerType()) {
    Diag(ArraySize->getLocStart(), diag::err_array_size_non_int)
      << ArraySize->getType() << ArraySize->getSourceRange();
    ArraySize->Destroy(Context);
    return QualType();
  }
  llvm::APSInt ConstVal(32);
  if (!ArraySize) {
    T = Context.getIncompleteArrayType(T, ASM, Quals);
  } else if (ArraySize->isValueDependent()) {
    T = Context.getDependentSizedArrayType(T, ArraySize, ASM, Quals);
  } else if (!ArraySize->isIntegerConstantExpr(ConstVal, Context) ||
             (!T->isDependentType() && !T->isConstantSizeType())) {
    // Per C99, a variable array is an array with either a non-constant
    // size or an element type that has a non-constant-size
    T = Context.getVariableArrayType(T, ArraySize, ASM, Quals);
  } else {
    // C99 6.7.5.2p1: If the expression is a constant expression, it shall
    // have a value greater than zero.
    if (ConstVal.isSigned()) {
      if (ConstVal.isNegative()) {
        Diag(ArraySize->getLocStart(),
             diag::err_typecheck_negative_array_size)
          << ArraySize->getSourceRange();
        return QualType();
      } else if (ConstVal == 0) {
        // GCC accepts zero sized static arrays.
        Diag(ArraySize->getLocStart(), diag::ext_typecheck_zero_array_size)
          << ArraySize->getSourceRange();
      }
    } 
    T = Context.getConstantArrayType(T, ConstVal, ASM, Quals);
  }
  // If this is not C99, extwarn about VLA's and C99 array size modifiers.
  if (!getLangOptions().C99) {
    if (ArraySize && !ArraySize->isTypeDependent() && 
        !ArraySize->isValueDependent() && 
        !ArraySize->isIntegerConstantExpr(Context))
      Diag(Loc, diag::ext_vla);
    else if (ASM != ArrayType::Normal || Quals != 0)
      Diag(Loc, diag::ext_c99_array_usage);
  }

  return T;
}
Пример #8
0
/// CheckDynamicCast - Check that a dynamic_cast\<DestType\>(SrcExpr) is valid.
/// Refer to C++ 5.2.7 for details. Dynamic casts are used mostly for runtime-
/// checked downcasts in class hierarchies.
void
CheckDynamicCast(Sema &Self, Expr *&SrcExpr, QualType DestType,
                 const SourceRange &OpRange,
                 const SourceRange &DestRange)
{
  QualType OrigDestType = DestType, OrigSrcType = SrcExpr->getType();
  DestType = Self.Context.getCanonicalType(DestType);

  // C++ 5.2.7p1: T shall be a pointer or reference to a complete class type,
  //   or "pointer to cv void".

  QualType DestPointee;
  const PointerType *DestPointer = DestType->getAsPointerType();
  const ReferenceType *DestReference = DestType->getAsReferenceType();
  if (DestPointer) {
    DestPointee = DestPointer->getPointeeType();
  } else if (DestReference) {
    DestPointee = DestReference->getPointeeType();
  } else {
    Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ref_or_ptr)
      << OrigDestType << DestRange;
    return;
  }

  const RecordType *DestRecord = DestPointee->getAsRecordType();
  if (DestPointee->isVoidType()) {
    assert(DestPointer && "Reference to void is not possible");
  } else if (DestRecord) {
    if (Self.RequireCompleteType(OpRange.getBegin(), DestPointee, 
                                    diag::err_bad_dynamic_cast_incomplete,
                                    DestRange))
      return;
  } else {
    Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
      << DestPointee.getUnqualifiedType() << DestRange;
    return;
  }

  // C++0x 5.2.7p2: If T is a pointer type, v shall be an rvalue of a pointer to
  //   complete class type, [...]. If T is an lvalue reference type, v shall be
  //   an lvalue of a complete class type, [...]. If T is an rvalue reference
  //   type, v shall be an expression having a complete effective class type,
  //   [...]

  QualType SrcType = Self.Context.getCanonicalType(OrigSrcType);
  QualType SrcPointee;
  if (DestPointer) {
    if (const PointerType *SrcPointer = SrcType->getAsPointerType()) {
      SrcPointee = SrcPointer->getPointeeType();
    } else {
      Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ptr)
        << OrigSrcType << SrcExpr->getSourceRange();
      return;
    }
  } else if (DestReference->isLValueReferenceType()) {
    if (SrcExpr->isLvalue(Self.Context) != Expr::LV_Valid) {
      Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_rvalue)
        << "dynamic_cast" << OrigDestType << OpRange;
    }
    SrcPointee = SrcType;
  } else {
    SrcPointee = SrcType;
  }

  const RecordType *SrcRecord = SrcPointee->getAsRecordType();
  if (SrcRecord) {
    if (Self.RequireCompleteType(OpRange.getBegin(), SrcPointee,
                                    diag::err_bad_dynamic_cast_incomplete,
                                    SrcExpr->getSourceRange()))
      return;
  } else {
    Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
      << SrcPointee.getUnqualifiedType() << SrcExpr->getSourceRange();
    return;
  }

  assert((DestPointer || DestReference) &&
    "Bad destination non-ptr/ref slipped through.");
  assert((DestRecord || DestPointee->isVoidType()) &&
    "Bad destination pointee slipped through.");
  assert(SrcRecord && "Bad source pointee slipped through.");

  // C++ 5.2.7p1: The dynamic_cast operator shall not cast away constness.
  if (!DestPointee.isAtLeastAsQualifiedAs(SrcPointee)) {
    Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_const_away)
      << "dynamic_cast" << OrigDestType << OrigSrcType << OpRange;
    return;
  }

  // C++ 5.2.7p3: If the type of v is the same as the required result type,
  //   [except for cv].
  if (DestRecord == SrcRecord) {
    return;
  }

  // C++ 5.2.7p5
  // Upcasts are resolved statically.
  if (DestRecord && Self.IsDerivedFrom(SrcPointee, DestPointee)) {
    Self.CheckDerivedToBaseConversion(SrcPointee, DestPointee,
                                      OpRange.getBegin(), OpRange);
    // Diagnostic already emitted on error.
    return;
  }

  // C++ 5.2.7p6: Otherwise, v shall be [polymorphic].
  const RecordDecl *SrcDecl = SrcRecord->getDecl()->getDefinition(Self.Context);
  assert(SrcDecl && "Definition missing");
  if (!cast<CXXRecordDecl>(SrcDecl)->isPolymorphic()) {
    Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_polymorphic)
      << SrcPointee.getUnqualifiedType() << SrcExpr->getSourceRange();
  }

  // Done. Everything else is run-time checks.
}