$ make ztime
Starting/stopping zsh 10 times
/usr/bin/time: illegal option -- f
usage: time [-al] [-h | -p] [-o file] utility [argument ...]
/usr/bin/time: illegal option -- f
usage: time [-al] [-h | -p] [-o file] utility [argument ...]
/usr/bin/time: illegal option -- f
usage: time [-al] [-h | -p] [-o file] utility [argument ...]
/usr/bin/time: illegal option -- f
usage: time [-al] [-h | -p] [-o file] utility [argument ...]
/usr/bin/time: illegal option -- f
usage: time [-al] [-h | -p] [-o file] utility [argument ...]
/usr/bin/time: illegal option -- f
usage: time [-al] [-h | -p] [-o file] utility [argument ...]
/usr/bin/time: illegal option -- f
usage: time [-al] [-h | -p] [-o file] utility [argument ...]
/usr/bin/time: illegal option -- f
usage: time [-al] [-h | -p] [-o file] utility [argument ...]
/usr/bin/time: illegal option -- f
usage: time [-al] [-h | -p] [-o file] utility [argument ...]
/usr/bin/time: illegal option -- f
usage: time [-al] [-h | -p] [-o file] utility [argument ...]
make: *** [ztime] Error 1