diff --git a/library/core/src/ops/range.rs b/library/core/src/ops/range.rs
index c5a7744d73b3..b1df5afa2022 100644
--- a/library/core/src/ops/range.rs
+++ b/library/core/src/ops/range.rs
@@ -742,6 +742,8 @@ impl<T: Copy> Bound<&T> {
     /// # Examples
     ///
     /// ```
+    /// #![feature(bound_copied)]
+    ///
     /// use std::ops::Bound::*;
     /// use std::ops::RangeBounds;
     ///