diff --git a/src/source_file.rs b/src/source_file.rs
index 6376bc49b69f..2b43ec94b6bd 100644
--- a/src/source_file.rs
+++ b/src/source_file.rs
@@ -66,7 +66,7 @@ where
         }
     }
 
-    #[cfg_attr(not(bootstrap), allow(non_local_definitions))]
+    #[allow(non_local_definitions)]
     impl From<&FileName> for rustc_span::FileName {
         fn from(filename: &FileName) -> rustc_span::FileName {
             match filename {