saw &WARN at ./Dir.sd.mk:10
saw &WARN at ./Dir.sd.mk:11
saw &WARN at ./sub/dir/Dir.sd.mk:15
+ saw &WARN at ./sub/dir/Dir.sd.mk:24
subdirmk: warning (unknown-warning): ./sub/dir/Dir.sd.mk:3: attempt to suppress unknown warning(s) `some-unknown-warning'