git mktag) ||
                                die "Could not create new tag object for $ref"
                        if git cat-file tag "$ref" | \
-                          grep '^-----BEGIN PGP SIGNATURE-----' >/dev/null 2>&1
+                          sane_grep '^-----BEGIN PGP SIGNATURE-----' >/dev/null 2>&1
                        then
                                warn "gpg signature stripped from tag object $sha1t"
                        fi