$ git clone -n https://src.fedoraproject.org/rpms/hdf5.git /var/lib/mock/f42-build-864752-172559/root/chroot_tmpdir/scmroot/hdf5
Cloning into '/var/lib/mock/f42-build-864752-172559/root/chroot_tmpdir/scmroot/hdf5'...
$ git fetch origin bdeffdd08d4467278d9671cd2551a4162304aebf:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/hdf5
 * [new ref]         bdeffdd08d4467278d9671cd2551a4162304aebf -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bdeffdd Fix ownership of %%{_libdir}/hdf5