$ git clone -n https://src.fedoraproject.org/rpms/compiler-rt.git /var/lib/mock/f38-build-side-42-init-devel-1077756-29816/root/chroot_tmpdir/scmroot/compiler-rt
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1077756-29816/root/chroot_tmpdir/scmroot/compiler-rt'...
$ git fetch origin 859d81e3aa627ff2492993c18c37bf71442b1019:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/compiler-rt
 * [new ref]         859d81e3aa627ff2492993c18c37bf71442b1019 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 859d81e Update to LLVM 16.0.6