// This doesn't work:
//#[derive(Clone, Copy)]
struct Copyable<'a, N: 'static> {
    #[allow(dead_code)]
    field: &'a N,
}

// Resort to manual implementation:
impl<'a, N> Clone for Copyable<'a, N> {
    fn clone(&self) -> Self {
        *self
    }
}

impl<'a, N> Copy for Copyable<'a, N> {
}

struct NonCopy;

fn main() {
    let thing = NonCopy;

    let copyable = Copyable {
        field: &thing,
    };

    drop(copyable);
    drop(copyable);
}