Weak pointer sizes

main.rs

use std::sync::{Arc, Weak};
fn main() {
    struct A {
        valid: Option<Arc<()>>
    }

    impl A {


    fn weak(&mut self) -> Weak<()> {
        let valid = Arc::new(());
        let weak_valid = Arc::downgrade(&valid);
        self.valid = Some(valid);
        weak_valid
    }

    }
    struct B {
        valid: Weak<()>
    }

    struct C {}

    let mut a = A { valid: None };

    println!("{}", size_of::<A>());
    println!("{}", size_of::<HashMap<u64, u64>>());
    println!("1 Size of s: {} bytes", size_of_val(&a));

    let b = B{ valid: a.weak() };

    println!("{}", size_of::<B>());
    println!("2 Size of s: {} bytes", size_of_val(&b));

    b.valid.upgrade().unwrap();

    println!("3 Size of s: {} bytes", size_of_val(&b));

    drop(a);

    println!("4 Size of s: {} bytes", size_of_val(&b));
    // b.valid.upgrade().unwrap();
}