Esempio n. 1
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ExprResult Sema::ActOnFunctionCallExpr(Scope *S, FunctionDefn *FnD, Expr* Fn,
		SourceLocation LParenLoc, MultiExprArg args, SourceLocation RParenLoc) {
	unsigned NumArgs = args.size();
	Expr **Args = args.release();

	FunctionCall *FNCall = new(getASTContext())FunctionCall(getASTContext(),
			Fn,Args,NumArgs,FnD->getType(),mlang::VK_RValue,RParenLoc);
	if(FNCall==NULL)
		return ExprError();

	return Owned(FNCall);
}
Esempio n. 2
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ExprResult Sema::ActOnRowVectorExpr(MultiExprArg Rows) {
	Expr** exprs = Rows.release();
	unsigned NumRows = Rows.size();
	ASTContext &ctx = getASTContext();
	Type EleTy = exprs[0]->getType();
	Type VTy = Context.getVectorType(EleTy, NumRows,
			VectorType::GenericVector, true);

	RowVectorExpr *E = new (ctx) RowVectorExpr(ctx,	exprs, NumRows, VTy);
	if(E == NULL)
		return ExprError();
	return Owned(E);
}
Esempio n. 3
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ExprResult Sema::ActOnArrayIndexExpr(Scope *S, VarDefn *Var, Expr *Base,
		SourceLocation LLoc, MultiExprArg args, SourceLocation RLoc,
		bool isCell) {
	Expr **Args = args.release();
	unsigned NumArgs = args.size();

	// FIXME : we should not use Base type here
	ArrayIndex *Ai = new(getASTContext())ArrayIndex(getASTContext(),
			Base,Args,NumArgs,Base->getType(),mlang::VK_LValue,RLoc, isCell);

	if(Ai==NULL)
		return ExprError();

	return Owned(Ai);
}
Esempio n. 4
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ExprResult Sema::BuildMatrix(MultiExprArg Mats, SourceLocation LBracketLoc,
		SourceLocation RBracketLoc) {
  Expr** exprs = Mats.release();
  unsigned NumRows = Mats.size();
  unsigned NumCols = 1; //FIXME
  RowVectorExpr *VE = cast<RowVectorExpr>(exprs[0]);
  if(VE)
	  NumCols = VE->getNumSubExprs();

  ASTContext &ctx = getASTContext();
  Type T = exprs[0]->getType();
  const VectorType *VT = T->getAs<VectorType>();
  Type EleTy = VT->getElementType();
  Type MTy = Context.getMatrixType(EleTy, NumRows, NumCols,
  			MatrixType::Full);

  ConcatExpr *E = new (ctx) ConcatExpr(ctx,	exprs, NumRows, MTy,
		  LBracketLoc, RBracketLoc);
  if(E==NULL)
  		return ExprError();
  return Owned(E);
}
Esempio n. 5
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/// 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()));
}
Esempio n. 6
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/// 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));
}
Esempio n. 7
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/// \param ReceiverType The type of the object receiving the
/// message. When \p ReceiverTypeInfo is non-NULL, this is the same
/// type as that refers to. For a superclass send, this is the type of
/// the superclass.
///
/// \param SuperLoc The location of the "super" keyword in a
/// superclass message.
///
/// \param Sel The selector to which the message is being sent.
///
/// \param Method The method that this class message is invoking, if
/// already known.
///
/// \param LBracLoc The location of the opening square bracket ']'.
///
/// \param RBrac The location of the closing square bracket ']'.
///
/// \param Args The message arguments.
ExprResult Sema::BuildClassMessage(TypeSourceInfo *ReceiverTypeInfo,
                                   QualType ReceiverType,
                                   SourceLocation SuperLoc,
                                   Selector Sel,
                                   ObjCMethodDecl *Method,
                                   SourceLocation LBracLoc, 
                                   SourceLocation SelectorLoc,
                                   SourceLocation RBracLoc,
                                   MultiExprArg ArgsIn) {
  SourceLocation Loc = SuperLoc.isValid()? SuperLoc
    : ReceiverTypeInfo->getTypeLoc().getSourceRange().getBegin();
  if (LBracLoc.isInvalid()) {
    Diag(Loc, diag::err_missing_open_square_message_send)
      << FixItHint::CreateInsertion(Loc, "[");
    LBracLoc = Loc;
  }
  
  if (ReceiverType->isDependentType()) {
    // If the receiver type is dependent, we can't type-check anything
    // at this point. Build a dependent expression.
    unsigned NumArgs = ArgsIn.size();
    Expr **Args = reinterpret_cast<Expr **>(ArgsIn.release());
    assert(SuperLoc.isInvalid() && "Message to super with dependent type");
    return Owned(ObjCMessageExpr::Create(Context, ReceiverType,
                                         VK_RValue, LBracLoc, ReceiverTypeInfo,
                                         Sel, SelectorLoc, /*Method=*/0,
                                         Args, NumArgs, RBracLoc));
  }
  
  // Find the class to which we are sending this message.
  ObjCInterfaceDecl *Class = 0;
  const ObjCObjectType *ClassType = ReceiverType->getAs<ObjCObjectType>();
  if (!ClassType || !(Class = ClassType->getInterface())) {
    Diag(Loc, diag::err_invalid_receiver_class_message)
      << ReceiverType;
    return ExprError();
  }
  assert(Class && "We don't know which class we're messaging?");
  (void)DiagnoseUseOfDecl(Class, Loc);
  // Find the method we are messaging.
  if (!Method) {
    if (Class->isForwardDecl()) {
      // A forward class used in messaging is treated as a 'Class'
      Diag(Loc, diag::warn_receiver_forward_class) << Class->getDeclName();
      Method = LookupFactoryMethodInGlobalPool(Sel, 
                                               SourceRange(LBracLoc, RBracLoc));
      if (Method)
        Diag(Method->getLocation(), diag::note_method_sent_forward_class)
          << Method->getDeclName();
    }
    if (!Method)
      Method = Class->lookupClassMethod(Sel);

    // If we have an implementation in scope, check "private" methods.
    if (!Method)
      Method = LookupPrivateClassMethod(Sel, Class);

    if (Method && DiagnoseUseOfDecl(Method, Loc))
      return ExprError();
  }

  // Check the argument types and determine the result type.
  QualType ReturnType;
  ExprValueKind VK = VK_RValue;

  unsigned NumArgs = ArgsIn.size();
  Expr **Args = reinterpret_cast<Expr **>(ArgsIn.release());
  if (CheckMessageArgumentTypes(Args, NumArgs, Sel, Method, true,
                                LBracLoc, RBracLoc, ReturnType, VK))
    return ExprError();

  if (Method && !Method->getResultType()->isVoidType() &&
      RequireCompleteType(LBracLoc, Method->getResultType(), 
                          diag::err_illegal_message_expr_incomplete_type))
    return ExprError();

  // Construct the appropriate ObjCMessageExpr.
  Expr *Result;
  if (SuperLoc.isValid())
    Result = ObjCMessageExpr::Create(Context, ReturnType, VK, LBracLoc, 
                                     SuperLoc, /*IsInstanceSuper=*/false, 
                                     ReceiverType, Sel, SelectorLoc,
                                     Method, Args, NumArgs, RBracLoc);
  else
    Result = ObjCMessageExpr::Create(Context, ReturnType, VK, LBracLoc, 
                                     ReceiverTypeInfo, Sel, SelectorLoc,
                                     Method, Args, NumArgs, RBracLoc);
  return MaybeBindToTemporary(Result);
}
Esempio n. 8
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/// \brief Build an Objective-C instance message expression.
///
/// This routine takes care of both normal instance messages and
/// instance messages to the superclass instance.
///
/// \param Receiver The expression that computes the object that will
/// receive this message. This may be empty, in which case we are
/// sending to the superclass instance and \p SuperLoc must be a valid
/// source location.
///
/// \param ReceiverType The (static) type of the object receiving the
/// message. When a \p Receiver expression is provided, this is the
/// same type as that expression. For a superclass instance send, this
/// is a pointer to the type of the superclass.
///
/// \param SuperLoc The location of the "super" keyword in a
/// superclass instance message.
///
/// \param Sel The selector to which the message is being sent.
///
/// \param Method The method that this instance message is invoking, if
/// already known.
///
/// \param LBracLoc The location of the opening square bracket ']'.
///
/// \param RBrac The location of the closing square bracket ']'.
///
/// \param Args The message arguments.
ExprResult Sema::BuildInstanceMessage(Expr *Receiver,
                                      QualType ReceiverType,
                                      SourceLocation SuperLoc,
                                      Selector Sel,
                                      ObjCMethodDecl *Method,
                                      SourceLocation LBracLoc, 
                                      SourceLocation SelectorLoc,
                                      SourceLocation RBracLoc,
                                      MultiExprArg ArgsIn) {
  // The location of the receiver.
  SourceLocation Loc = SuperLoc.isValid()? SuperLoc : Receiver->getLocStart();
  
  if (LBracLoc.isInvalid()) {
    Diag(Loc, diag::err_missing_open_square_message_send)
      << FixItHint::CreateInsertion(Loc, "[");
    LBracLoc = Loc;
  }

  // If we have a receiver expression, perform appropriate promotions
  // and determine receiver type.
  if (Receiver) {
    if (Receiver->isTypeDependent()) {
      // If the receiver is type-dependent, we can't type-check anything
      // at this point. Build a dependent expression.
      unsigned NumArgs = ArgsIn.size();
      Expr **Args = reinterpret_cast<Expr **>(ArgsIn.release());
      assert(SuperLoc.isInvalid() && "Message to super with dependent type");
      return Owned(ObjCMessageExpr::Create(Context, Context.DependentTy,
                                           VK_RValue, LBracLoc, Receiver, Sel, 
                                           SelectorLoc, /*Method=*/0,
                                           Args, NumArgs, RBracLoc));
    }

    // If necessary, apply function/array conversion to the receiver.
    // C99 6.7.5.3p[7,8].
    DefaultFunctionArrayLvalueConversion(Receiver);
    ReceiverType = Receiver->getType();
  }

  if (!Method) {
    // Handle messages to id.
    bool receiverIsId = ReceiverType->isObjCIdType();
    if (receiverIsId || ReceiverType->isBlockPointerType() ||
        (Receiver && Context.isObjCNSObjectType(Receiver->getType()))) {
      Method = LookupInstanceMethodInGlobalPool(Sel, 
                                                SourceRange(LBracLoc, RBracLoc),
                                                receiverIsId);
      if (!Method)
        Method = LookupFactoryMethodInGlobalPool(Sel, 
                                                 SourceRange(LBracLoc, RBracLoc),
                                                 receiverIsId);
    } else if (ReceiverType->isObjCClassType() ||
               ReceiverType->isObjCQualifiedClassType()) {
      // Handle messages to Class.
      if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) {
        if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface()) {
          // First check the public methods in the class interface.
          Method = ClassDecl->lookupClassMethod(Sel);

          if (!Method)
            Method = LookupPrivateClassMethod(Sel, ClassDecl);

          // FIXME: if we still haven't found a method, we need to look in
          // protocols (if we have qualifiers).
        }
        if (Method && DiagnoseUseOfDecl(Method, Loc))
          return ExprError();
      }
      if (!Method) {
        // If not messaging 'self', look for any factory method named 'Sel'.
        if (!Receiver || !isSelfExpr(Receiver)) {
          Method = LookupFactoryMethodInGlobalPool(Sel, 
                                               SourceRange(LBracLoc, RBracLoc),
                                                   true);
          if (!Method) {
            // If no class (factory) method was found, check if an _instance_
            // method of the same name exists in the root class only.
            Method = LookupInstanceMethodInGlobalPool(Sel,
                                               SourceRange(LBracLoc, RBracLoc),
                                                      true);
            if (Method)
                if (const ObjCInterfaceDecl *ID =
                  dyn_cast<ObjCInterfaceDecl>(Method->getDeclContext())) {
                if (ID->getSuperClass())
                  Diag(Loc, diag::warn_root_inst_method_not_found)
                    << Sel << SourceRange(LBracLoc, RBracLoc);
              }
          }
        }
      }
    } else {
      ObjCInterfaceDecl* ClassDecl = 0;

      // We allow sending a message to a qualified ID ("id<foo>"), which is ok as
      // long as one of the protocols implements the selector (if not, warn).
      if (const ObjCObjectPointerType *QIdTy 
                                   = ReceiverType->getAsObjCQualifiedIdType()) {
        // Search protocols for instance methods.
        Method = LookupMethodInQualifiedType(Sel, QIdTy, true);
        if (!Method)
          Method = LookupMethodInQualifiedType(Sel, QIdTy, false);
      } else if (const ObjCObjectPointerType *OCIType
                   = ReceiverType->getAsObjCInterfacePointerType()) {
        // We allow sending a message to a pointer to an interface (an object).
        ClassDecl = OCIType->getInterfaceDecl();
        // FIXME: consider using LookupInstanceMethodInGlobalPool, since it will be
        // faster than the following method (which can do *many* linear searches).
        // The idea is to add class info to MethodPool.
        Method = ClassDecl->lookupInstanceMethod(Sel);

        if (!Method)
          // Search protocol qualifiers.
          Method = LookupMethodInQualifiedType(Sel, OCIType, true);
        
        bool forwardClass = false;
        if (!Method) {
          // If we have implementations in scope, check "private" methods.
          Method = LookupPrivateInstanceMethod(Sel, ClassDecl);

          if (!Method && (!Receiver || !isSelfExpr(Receiver))) {
            // If we still haven't found a method, look in the global pool. This
            // behavior isn't very desirable, however we need it for GCC
            // compatibility. FIXME: should we deviate??
            if (OCIType->qual_empty()) {
              Method = LookupInstanceMethodInGlobalPool(Sel,
                                                 SourceRange(LBracLoc, RBracLoc));
              forwardClass = OCIType->getInterfaceDecl()->isForwardDecl();
              if (Method && !forwardClass)
                Diag(Loc, diag::warn_maynot_respond)
                  << OCIType->getInterfaceDecl()->getIdentifier() << Sel;
            }
          }
        }
        if (Method && DiagnoseUseOfDecl(Method, Loc, forwardClass))
          return ExprError();
      } else if (!Context.getObjCIdType().isNull() &&
                 (ReceiverType->isPointerType() || 
                  ReceiverType->isIntegerType())) {
        // Implicitly convert integers and pointers to 'id' but emit a warning.
        Diag(Loc, diag::warn_bad_receiver_type)
          << ReceiverType 
          << Receiver->getSourceRange();
        if (ReceiverType->isPointerType())
          ImpCastExprToType(Receiver, Context.getObjCIdType(), 
                            CK_BitCast);
        else {
          // TODO: specialized warning on null receivers?
          bool IsNull = Receiver->isNullPointerConstant(Context,
                                              Expr::NPC_ValueDependentIsNull);
          ImpCastExprToType(Receiver, Context.getObjCIdType(),
                            IsNull ? CK_NullToPointer : CK_IntegralToPointer);
        }
        ReceiverType = Receiver->getType();
      } 
      else if (getLangOptions().CPlusPlus &&
               !PerformContextuallyConvertToObjCId(Receiver)) {
        if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Receiver)) {
          Receiver = ICE->getSubExpr();
          ReceiverType = Receiver->getType();
        }
        return BuildInstanceMessage(Receiver,
                                    ReceiverType,
                                    SuperLoc,
                                    Sel,
                                    Method,
                                    LBracLoc,
                                    SelectorLoc,
                                    RBracLoc,
                                    move(ArgsIn));
      } else {
        // Reject other random receiver types (e.g. structs).
        Diag(Loc, diag::err_bad_receiver_type)
          << ReceiverType << Receiver->getSourceRange();
        return ExprError();
      }
    }
  }

  // Check the message arguments.
  unsigned NumArgs = ArgsIn.size();
  Expr **Args = reinterpret_cast<Expr **>(ArgsIn.release());
  QualType ReturnType;
  ExprValueKind VK = VK_RValue;
  bool ClassMessage = (ReceiverType->isObjCClassType() ||
                       ReceiverType->isObjCQualifiedClassType());
  if (CheckMessageArgumentTypes(Args, NumArgs, Sel, Method, ClassMessage,
                                LBracLoc, RBracLoc, ReturnType, VK))
    return ExprError();
  
  if (Method && !Method->getResultType()->isVoidType() &&
      RequireCompleteType(LBracLoc, Method->getResultType(), 
                          diag::err_illegal_message_expr_incomplete_type))
    return ExprError();

  // Construct the appropriate ObjCMessageExpr instance.
  Expr *Result;
  if (SuperLoc.isValid())
    Result = ObjCMessageExpr::Create(Context, ReturnType, VK, LBracLoc,
                                     SuperLoc,  /*IsInstanceSuper=*/true,
                                     ReceiverType, Sel, SelectorLoc, Method, 
                                     Args, NumArgs, RBracLoc);
  else
    Result = ObjCMessageExpr::Create(Context, ReturnType, VK, LBracLoc,
                                     Receiver, Sel, SelectorLoc, Method,
                                     Args, NumArgs, RBracLoc);
  return MaybeBindToTemporary(Result);
}