diff --git a/library/core/src/slice/iter.rs b/library/core/src/slice/iter.rs index c5dffcf7e8f7..ac096afb38af 100644 --- a/library/core/src/slice/iter.rs +++ b/library/core/src/slice/iter.rs @@ -2232,6 +2232,14 @@ impl<'a, T, const N: usize> Iterator for ArrayWindows<'a, T, N> { fn last(self) -> Option { self.v.last_chunk() } + + unsafe fn __iterator_get_unchecked(&mut self, idx: usize) -> Self::Item { + // SAFETY: since the caller guarantees that `idx` is in bounds, + // which means that `idx` cannot overflow an `isize`, and the + // "slice" created by `cast_array` is a subslice of `self.v` + // thus is guaranteed to be valid for the lifetime `'a` of `self.v`. + unsafe { &*self.v.as_ptr().add(idx).cast_array() } + } } #[stable(feature = "array_windows", since = "1.94.0")] @@ -2266,6 +2274,16 @@ unsafe impl TrustedLen for ArrayWindows<'_, T, N> {} #[stable(feature = "array_windows", since = "1.94.0")] impl FusedIterator for ArrayWindows<'_, T, N> {} +#[doc(hidden)] +#[unstable(feature = "trusted_random_access", issue = "none")] +unsafe impl TrustedRandomAccess for ArrayWindows<'_, T, N> {} + +#[doc(hidden)] +#[unstable(feature = "trusted_random_access", issue = "none")] +unsafe impl TrustedRandomAccessNoCoerce for ArrayWindows<'_, T, N> { + const MAY_HAVE_SIDE_EFFECT: bool = false; +} + /// An iterator over a slice in (non-overlapping) chunks (`chunk_size` elements at a /// time), starting at the end of the slice. ///