$ git clone -n https://src.fedoraproject.org/rpms/R-Rcpp.git /var/lib/mock/f41-build-821352-152530/root/chroot_tmpdir/scmroot/R-Rcpp
Cloning into '/var/lib/mock/f41-build-821352-152530/root/chroot_tmpdir/scmroot/R-Rcpp'...
$ git fetch origin 2b38483febe9892962c6e28df5966c0cb62a8de1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-Rcpp
 * [new ref]         2b38483febe9892962c6e28df5966c0cb62a8de1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2b38483 Update to 1.0.13