Rule "undoretry" gives this warning when it finds an UNDO statement without options like RETRY/LEAVE/UNDO/NEXT.
the risc:
"UNDO" behaves like "UNDO, RETRY" but RETRY is almost never desired.
How to suppress these warnings:
You should specify at least something like "UNDO, LEAVE labelname", or even "UNDO, RETRY" to confirm the default.
See also: suppress warnings.