// Copyright 2017 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. use std::cell::Cell; use std::mem; struct Aligned<'a> { drop_count: &'a Cell } #[inline(never)] fn check_align(ptr: *const Aligned) { assert_eq!(ptr as usize % mem::align_of::(), 0); } impl<'a> Drop for Aligned<'a> { fn drop(&mut self) { check_align(self); self.drop_count.set(self.drop_count.get() + 1); } } #[repr(packed)] struct Packed<'a>(u8, Aligned<'a>); fn main() { let drop_count = &Cell::new(0); { let mut p = Packed(0, Aligned { drop_count }); p.1 = Aligned { drop_count }; assert_eq!(drop_count.get(), 1); } assert_eq!(drop_count.get(), 2); }