Skip into_iter() for arrays before 2021

library/core/src/array/mod.rs

@@ -155,6 +155,10 @@ impl<T: fmt::Debug, const N: usize> fmt::Debug for [T; N] {
     }
 }
 
+// Note: the `#[rustc_skip_array_during_method_dispatch]` on `trait IntoIterator`
+// hides this implementation from explicit `.into_iter()` calls on editions < 2021,
+// so those calls will still resolve to the slice implementation, by reference.
+#[cfg(not(bootstrap))]
 #[stable(feature = "array_into_iter_impl", since = "1.53.0")]
 impl<T, const N: usize> IntoIterator for [T; N] {
     type Item = T;