@@ -31,11 +31,11 @@
 @interface OFMessagePackExtension: OFObject <OFMessagePackRepresentation,
     OFCopying>
 {
 	int8_t _type;
 	OFData *_data;
-	OF_RESERVE_IVARS(4)
+	OF_RESERVE_IVARS(OFMessagePackExtension, 4)
 }
 
 /*!
  * @brief The MessagePack extension type.
  */