diff --git a/src/formatting.rs b/src/formatting.rs
index b69ecdc5cb8..e0403574eeb 100644
--- a/src/formatting.rs
+++ b/src/formatting.rs
@@ -34,7 +34,7 @@ impl<'b, T: Write + 'b> Session<'b, T> {
             return Err(ErrorKind::VersionMismatch);
         }
 
-        rustc_span::with_session_globals(self.config.edition().into(), || {
+        rustc_span::create_session_if_not_set_then(self.config.edition().into(), |_| {
             if self.config.disable_all_formatting() {
                 // When the input is from stdin, echo back the input.
                 if let Input::Text(ref buf) = input {