Variable TRAILER.MVS has a blank line at the end. The statements end in line 18 and the last line 19 is empty.
This leads to unsightly and confusing behavior when running jobs on the IBM / ZOS system. The blank line is interpreted as a SYSIN statement, but has no function.
Release : 12.3
Workaround: Remove 19 line
Solution: Will be fixed in a future release (TBD)