Shared via Rust Playground

playground.rs

struct Foo<'a> {
    x: &'a u32,
    y: u32,
}

#[allow(dead_code)]
fn bar<'a>(f: &'a mut Foo<'a>, _z: &'a u32) {
    f.x = &f.y;
}

fn main() {
    let z = &32u32;
    let mut f = Foo{x: z, y: 33u32};
    {
        let f2 = &mut f;
        bar(f2, z);
    }
    // println!("{}", f.x);
}