diff options
Diffstat (limited to 'rust/alloc/raw_vec.rs')
| -rw-r--r-- | rust/alloc/raw_vec.rs | 30 |
1 files changed, 20 insertions, 10 deletions
diff --git a/rust/alloc/raw_vec.rs b/rust/alloc/raw_vec.rs index 65d5ce15828e..a7425582a323 100644 --- a/rust/alloc/raw_vec.rs +++ b/rust/alloc/raw_vec.rs @@ -471,16 +471,26 @@ impl<T, A: Allocator> RawVec<T, A> { let (ptr, layout) = if let Some(mem) = self.current_memory() { mem } else { return Ok(()) }; // See current_memory() why this assert is here let _: () = const { assert!(mem::size_of::<T>() % mem::align_of::<T>() == 0) }; - let ptr = unsafe { - // `Layout::array` cannot overflow here because it would have - // overflowed earlier when capacity was larger. - let new_size = mem::size_of::<T>().unchecked_mul(cap); - let new_layout = Layout::from_size_align_unchecked(new_size, layout.align()); - self.alloc - .shrink(ptr, layout, new_layout) - .map_err(|_| AllocError { layout: new_layout, non_exhaustive: () })? - }; - self.set_ptr_and_cap(ptr, cap); + + // If shrinking to 0, deallocate the buffer. We don't reach this point + // for the T::IS_ZST case since current_memory() will have returned + // None. + if cap == 0 { + unsafe { self.alloc.deallocate(ptr, layout) }; + self.ptr = Unique::dangling(); + self.cap = 0; + } else { + let ptr = unsafe { + // `Layout::array` cannot overflow here because it would have + // overflowed earlier when capacity was larger. + let new_size = mem::size_of::<T>().unchecked_mul(cap); + let new_layout = Layout::from_size_align_unchecked(new_size, layout.align()); + self.alloc + .shrink(ptr, layout, new_layout) + .map_err(|_| AllocError { layout: new_layout, non_exhaustive: () })? + }; + self.set_ptr_and_cap(ptr, cap); + } Ok(()) } } |