unable to find utility "mkdep"

[Jan Stary]

This is 10.13.2 with XCode 9.2

$ mkdep *.c
mkdep: error: unable to find utility "mkdep", not a developer tool or in PATH

$ which mkdep
/usr/bin/mkdep

$ echo $PATH
/Users/hans/bin:/opt/local/bin:/opt/local/sbin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin

Am I missing something obvious?

        Jan