$ git clone -n https://src.fedoraproject.org/rpms/rust-darling_core0.14.git /var/lib/mock/f41-build-side-1-2928782-35102/root/chroot_tmpdir/scmroot/rust-darling_core0.14
Cloning into '/var/lib/mock/f41-build-side-1-2928782-35102/root/chroot_tmpdir/scmroot/rust-darling_core0.14'...
$ git fetch origin 2256c4bf3327ac02fe6c997a6a7b0a5a1764e039:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-darling_core0.14
 * [new ref]         2256c4bf3327ac02fe6c997a6a7b0a5a1764e039 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2256c4b compat package no longer needed