$ git clone -n https://src.fedoraproject.org/rpms/rust-sha-1.git /var/lib/mock/f38-build-side-43-rust-devel-1410618-31421/root/chroot_tmpdir/scmroot/rust-sha-1
Cloning into '/var/lib/mock/f38-build-side-43-rust-devel-1410618-31421/root/chroot_tmpdir/scmroot/rust-sha-1'...
$ git fetch origin 0da2c86652e803e2c0161dbf888d95e1c65fc39f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-sha-1
 * [new ref]         0da2c86652e803e2c0161dbf888d95e1c65fc39f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0da2c86 Enable feature for using optimized assembly implementations