$ git clone -n https://src.fedoraproject.org/forks/u2fsdgvkx1/rpms/llvm.git /var/lib/mock/f45-build-414-243/root/chroot_tmpdir/scmroot/llvm
Cloning into '/var/lib/mock/f45-build-414-243/root/chroot_tmpdir/scmroot/llvm'...
$ git fetch origin bd08a236b4ede848bcd32e333ac45b8e041dfda4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/forks/u2fsdgvkx1/rpms/llvm
 * [new ref]         bd08a236b4ede848bcd32e333ac45b8e041dfda4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bd08a23 Build LLVM with GCC on riscv64