$ git clone -n https://src.fedoraproject.org/rpms/shaderc.git /var/lib/mock/f39-build-1852732-42340/root/chroot_tmpdir/scmroot/shaderc
Cloning into '/var/lib/mock/f39-build-1852732-42340/root/chroot_tmpdir/scmroot/shaderc'...
$ git fetch origin a317187e6553ac3b6d8b2e471ed3959a3358b66d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/shaderc
 * [new ref]         a317187e6553ac3b6d8b2e471ed3959a3358b66d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a317187 update to 1.3.268.0 SDK