$ git clone -n https://src.fedoraproject.org/rpms/rust-derive_builder_macro0.12.git /var/lib/mock/f41-build-side-1-3124870-39482/root/chroot_tmpdir/scmroot/rust-derive_builder_macro0.12
Cloning into '/var/lib/mock/f41-build-side-1-3124870-39482/root/chroot_tmpdir/scmroot/rust-derive_builder_macro0.12'...
$ git fetch origin 56960d828e4d7d446d2ef19d1824f33c9088f360:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-derive_builder_macro0.12
 * [new ref]         56960d828e4d7d446d2ef19d1824f33c9088f360 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 56960d8 compat package no longer needed