struct S {
    v: i32
}

fn main()
{
    let mut t = Box::new(S{v: 666});
    let s;
    let s1;

    println!("{}", t.v);
    t.v = 0;
    println!("{}", t.v);
    s   = &t;
    s1  = &mut t;
    println!("{} {}", s.v, s1.v);
}