Account for actual backing buffer size with Arc included during dealloc
@@ -115,7 +115,7 @@ impl Drop for IVec {
let slice: &mut [u8] = std::mem::transmute(data);
let len = slice.len();
let layout = Layout::from_size_align_unchecked(
- len,
+ len + ARC_SZ,
std::mem::size_of::<AtomicUsize>(),
);
