MPP query failed if the return column has Enum type

[windtalker]

mysql> desc test_enum;
+-------+-------------------+------+------+---------+-------+
| Field | Type              | Null | Key  | Default | Extra |
+-------+-------------------+------+------+---------+-------+
| id    | int(11)           | YES  |      | NULL    |       |
| value | enum('a','b','c') | YES  |      | NULL    |       |
+-------+-------------------+------+------+---------+-------+
2 rows in set (0.00 sec)

mysql> select * from test_enum;
+------+-------+
| id   | value |
+------+-------+
|    1 | a     |
|    2 | b     |
+------+-------+
2 rows in set (0.01 sec)

mysql>  select * from test_enum a join test_enum b on a.id = b.id;
ERROR 1105 (HY000): DB::Exception: DataTypeEnum enumeration cannot be empty