invalid SHOW CREATE TABLE for tables in utf16 charset

MariaDB [test]>  CREATE TABLE t (i text DEFAULT repeat('m',5), a int) CHARSET=utf16;

Query OK, 0 rows affected (0,039 sec)

MariaDB [test]> show create table t;

+-------+---------------------------------------------------------------------------------------------------------------------------------------------------------+

| Table | Create Table                                                                                                                                            |

+-------+---------------------------------------------------------------------------------------------------------------------------------------------------------+

| t     | CREATE TABLE `t` (

  `i` text DEFAULT  r e p e a t('m',5),

  `a` int(11) DEFAULT NULL

) ENGINE=InnoDB DEFAULT CHARSET=utf16 COLLATE=utf16_uca1400_ai_ci |

+-------+---------------------------------------------------------------------------------------------------------------------------------------------------------+

1 row in set (0,002 sec)

MariaDB [test]> CREATE or replace TABLE t (i text DEFAULT concat('m','a'), a int)  charset=utf16;

Query OK, 0 rows affected (0,059 sec)

MariaDB [test]> show create table t;

+-------+-----------------------------------------------------------------------------------------------------------------------------------------------------------+

| Table | Create Table                                                                                                                                              |

+-------+-----------------------------------------------------------------------------------------------------------------------------------------------------------+

| t     | CREATE TABLE `t` (

  `i` text DEFAULT  c o n c a t('m','a'),

  `a` int(11) DEFAULT NULL

) ENGINE=InnoDB DEFAULT CHARSET=utf16 COLLATE=utf16_uca1400_ai_ci |

+-------+-----------------------------------------------------------------------------------------------------------------------------------------------------------+

1 row in set (0,002 sec)

--

-- Table structure for table `t`

--

DROP TABLE IF EXISTS `t`;

/*!40101 SET @saved_cs_client     = @@character_set_client */;

/*!40101 SET character_set_client = utf8 */;

CREATE TABLE `t` (

  `i` text DEFAULT ;

/*!40101 SET character_set_client = @saved_cs_client */;