$ git clone -n https://src.fedoraproject.org/rpms/mingw-libsigc++30.git /var/lib/mock/f40-build-2211685-52225/root/chroot_tmpdir/scmroot/mingw-libsigc++30
Cloning into '/var/lib/mock/f40-build-2211685-52225/root/chroot_tmpdir/scmroot/mingw-libsigc++30'...
$ git fetch origin d672bb265a2b0419e9d64cbb3ab5924608f34273:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mingw-libsigc++30
 * [new ref]         d672bb265a2b0419e9d64cbb3ab5924608f34273 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d672bb2 Update to 3.6.0