1170 
1171 {
1172     # gh #17221
1173     my ($off1, $off2);
1174     my $x = eval { sprintf "%n0%n\x{100}", $off1, $off2 };
1175     is($@, "", "no exception");
1176     is($x, "0\x{100}", "reasonable result");
1177     is($off1, 0, "offset at start");
1178     is($off2, 1, "offset after 0");
1179 }
1180