diff --git a/src/liballoc/binary_heap.rs b/src/liballoc/binary_heap.rs index 668b61c51d8..fcadcb544c4 100644 --- a/src/liballoc/binary_heap.rs +++ b/src/liballoc/binary_heap.rs @@ -157,7 +157,7 @@ use core::ops::{Deref, DerefMut}; use core::iter::{FromIterator, FusedIterator}; -use core::mem::{swap, size_of}; +use core::mem::{swap, size_of, ManuallyDrop}; use core::ptr; use core::fmt; @@ -864,8 +864,7 @@ impl BinaryHeap { /// position with the value that was originally removed. struct Hole<'a, T: 'a> { data: &'a mut [T], - /// `elt` is always `Some` from new until drop. - elt: Option, + elt: ManuallyDrop, pos: usize, } @@ -879,7 +878,7 @@ impl<'a, T> Hole<'a, T> { let elt = ptr::read(&data[pos]); Hole { data, - elt: Some(elt), + elt: ManuallyDrop::new(elt), pos, } } @@ -892,7 +891,7 @@ impl<'a, T> Hole<'a, T> { /// Returns a reference to the element removed. #[inline] fn element(&self) -> &T { - self.elt.as_ref().unwrap() + &self.elt } /// Returns a reference to the element at `index`. @@ -925,7 +924,7 @@ impl<'a, T> Drop for Hole<'a, T> { // fill the hole again unsafe { let pos = self.pos; - ptr::write(self.data.get_unchecked_mut(pos), self.elt.take().unwrap()); + ptr::copy_nonoverlapping(&*self.elt, self.data.get_unchecked_mut(pos), 1); } } }