Class Obj

toys/use-after-free/src/main.rs:33–35

        val.as_ref().map(Owned::as_raw).unwrap_or(ptr::null_mut())
    }
    struct Obj<T> {
        ptr: AtomicPtr<T>,
    }
    impl<T> Obj<T> {
        fn null() -> Self {
            Obj {