//@ run-pass
//@ only-32bit too impatient for 2⁶⁴ items
//@ compile-flags: -C debug_assertions=no -C opt-level=3

fn main() {
    let n = usize::MAX as u64;
    assert_eq!((0..).by_ref().position(|i| i >= n), Some(usize::MAX));
    assert_eq!((0..).by_ref().position(|i| i > n), Some(0));
    assert_eq!((0..=n + 1).by_ref().position(|_| false), None);
}