diff --git a/tokio/build.rs b/tokio/build.rs
index 2d2ec5641c0..40ee43849dc 100644
--- a/tokio/build.rs
+++ b/tokio/build.rs
@@ -19,12 +19,13 @@ const CONST_MUTEX_NEW_PROBE: &str = r#"
 
 const AS_FD_PROBE: &str = r#"
 {
-    #![allow(unused_imports)]
-
+    #[allow(unused_imports)]
     #[cfg(unix)]
     use std::os::unix::prelude::AsFd as _;
+    #[allow(unused_imports)]
     #[cfg(windows)]
     use std::os::windows::prelude::AsSocket as _;
+    #[allow(unused_imports)]
     #[cfg(target = "wasm32-wasi")]
     use std::os::wasi::prelude::AsFd as _;
 }