$ git clone -n https://src.fedoraproject.org/rpms/libcxxabi.git /var/lib/mock/f31-build-93704-32429/root/chroot_tmpdir/scmroot/libcxxabi
Cloning into '/var/lib/mock/f31-build-93704-32429/root/chroot_tmpdir/scmroot/libcxxabi'...
$ git reset --hard 6f706103ff5ab877869cfe1bacc56a63ab4ba42a
HEAD is now at 6f70610 - Rebuilt for https://fedoraproject.org/wiki/Fedora_31_Mass_Rebuild