#![feature(allocator_api)]

#[test]
fn make_mut_leaks() {
    use std::alloc::Global;
    use std::rc::Rc;
    use std::sync::Arc;

    let alloc = Rc::new(Global);

    {
        let mut arc = Arc::new_in(123, alloc.clone());
        let weak = Arc::downgrade(&arc); // create a weak so make_mut steals the data
        _ = Arc::make_mut(&mut arc);
        assert_eq!(weak.upgrade(), None);
    }

    assert_eq!(Rc::strong_count(&alloc), 1); // if this is >1, we have a memory leak!
}