$ git clone -n https://src.fedoraproject.org/rpms/gtkmm3.0.git /var/lib/mock/f37-build-673866-75724/root/chroot_tmpdir/scmroot/gtkmm3.0
Cloning into '/var/lib/mock/f37-build-673866-75724/root/chroot_tmpdir/scmroot/gtkmm3.0'...
$ git reset --hard 40a18b125ce8132c11aea693221fa3f0090c0e2e
HEAD is now at 40a18b1 Require glibmm2.4 rather than glibmm24