static mut DROP_RAN: isize = 0; struct Foo; impl Drop for Foo { fn drop(&mut self) { unsafe { DROP_RAN += 1; } } } struct Fat { f: T, } pub fn main() { { let _x: Box> = Box::>::new(Fat { f: [Foo, Foo, Foo] }); } unsafe { assert_eq!(DROP_RAN, 3); } }