diff --git a/clippy_lints/src/strings.rs b/clippy_lints/src/strings.rs
index 3f9f56c451a..eb704a07451 100644
--- a/clippy_lints/src/strings.rs
+++ b/clippy_lints/src/strings.rs
@@ -63,7 +63,7 @@ declare_clippy_lint! {
     ///
     /// Use instead:
     /// ```rust
-    /// let x = "Hello".to_owned();
+    /// let mut x = "Hello".to_owned();
     /// x.push_str(", World");
     /// ```
     #[clippy::version = "pre 1.29.0"]