diff --git a/src/liballoc/borrow.rs b/src/liballoc/borrow.rs
index 74c80a08b12..ee1799fad8e 100644
--- a/src/liballoc/borrow.rs
+++ b/src/liballoc/borrow.rs
@@ -135,7 +135,7 @@ impl<T> ToOwned for T
 /// Another example showing how to keep `Cow` in a struct:
 ///
 /// ```
-/// use std::borrow::{Cow, ToOwned};
+/// use std::borrow::Cow;
 ///
 /// struct Items<'a, X: 'a> where [X]: ToOwned<Owned = Vec<X>> {
 ///     values: Cow<'a, [X]>,
diff --git a/src/libcore/cell.rs b/src/libcore/cell.rs
index 753f10e6a0a..3b888244341 100644
--- a/src/libcore/cell.rs
+++ b/src/libcore/cell.rs
@@ -1421,7 +1421,6 @@ impl<T: ?Sized + fmt::Display> fmt::Display for RefMut<'_, T> {
 ///
 /// ```
 /// use std::cell::UnsafeCell;
-/// use std::marker::Sync;
 ///
 /// # #[allow(dead_code)]
 /// struct NotThreadSafe<T> {