//# run
main() {
    let x: u64;
    let y: u64;
    let b: bool;
label b0:
    x = 0;
    b = true;
label while:
    jump_if_false (copy(b)) while_cont;
label while_body:
    y = move(x);
    b = false;
    jump while;
label while_cont:
    // invalid move
    assert(move(y) == 0, 42);
    return;
}