Build trivially (but permanently) broken

["T.V Raman" <raman@google.com>]

Since the last couple of days:
This is on Github @head.

make mostlyclean breaks ---
tried to refresh state by running autogen.sh -- no luck.

make[1]: Entering directory '/usr/local/google/home/raman/sourceforge/emacs/lib'
rm -f *.[ao] *-t \#* deps/*
rm -f core *.stackdump alloca.h byteswap.h dirent.h errno.h execinfo.h fcntl.h getopt.h getopt-cdefs.h ieee754.h inttypes.h limits.h signal.h stdalign.h stddef.h stdint.h stdio.h stdlib.h string.h sys/select.h sys/stat.h sys/time.h sys/types.h time.h unistd.h
rm -f Makefile
rm -fr deps
make[1]: Leaving directory '/usr/local/google/home/raman/sourceforge/emacs/lib'
make[1]: Entering directory '/usr/local/google/home/raman/sourceforge/emacs/src'
rm -f temacs core *.core \#* *.o
rm: invalid option -- '.'
Try 'rm ./-.o' to remove the file '-.o'.
Try 'rm --help' for more information.
Makefile:648: recipe for target 'mostlyclean' failed
-- 
Id: kg:/m/0285kf1