need a better error message

0: jdbc:drill:schema=dfs.tmp> SELECT MAX(AVG(c2)) OVER ( PARTITION BY c2 ORDER BY c2 ), c2 FROM `tblWnulls.parquet` GROUP BY c2;
Error: SYSTEM ERROR: SchemaChangeException: Failure while trying to materialize incoming schema.  Errors:

Error in expression at index -1.  Error: Missing function implementation: [castINT(BIT-OPTIONAL)].  Full expression: --UNKNOWN EXPRESSION--..

Fragment 0:0

[Error Id: 076464ff-7385-4bee-9704-38dec781af32 on centos-01.qa.lab:31010] (state=,code=0)