hide an #[allow] directive from the Arc::new_cyclic doc example

oconnor663 · oconnor663 · commit e0e64a89304d · 2022-04-07T18:00:46.000-07:00
diff --git a/library/alloc/src/sync.rs b/library/alloc/src/sync.rs
@@ -369,7 +369,7 @@ impl<T> Arc<T> {
     ///
     /// # Example
     /// ```
-    /// #![allow(dead_code)]
+    /// # #![allow(dead_code)]
     /// use std::sync::{Arc, Weak};
     ///
     /// struct Gadget {
