I found this in contrib/sepgsql/expected/label.out:
SECURITY LABEL ON COLUMN t2
IS 'system_u:object_r:sepgsql_ro_table_t:s0'; -- be failed
ERROR: improper relation name (too many dotted names): <nothing>
Contrast with:
SECURITY LABEL ON COLUMN t2.b
IS 'system_u:object_r:sepgsql_ro_table_t:s0'; -- ok
I guess what's happening is that it's calling makeRangeVarFromNameList()
with a list of length zero.
We should either fix the SECURITY LABEL command to catch that case
beforehand, or fix makeRangeVarFromNameList() to give a proper error
message, or both.