diff --git a/core/codegen/src/attribute/route/mod.rs b/core/codegen/src/attribute/route/mod.rs
index 8003dda430..1079f3066b 100644
--- a/core/codegen/src/attribute/route/mod.rs
+++ b/core/codegen/src/attribute/route/mod.rs
@@ -242,7 +242,7 @@ fn responder_outcome_expr(route: &Route) -> TokenStream {
         .map(|a| quote_spanned!(a.span() => .await));
 
     define_spanned_export!(ret_span => __req, _route);
-    quote_spanned! { ret_span =>
+    quote_spanned! { Span::mixed_site().located_at(ret_span) =>
         let ___responder = #user_handler_fn_name(#(#parameter_names),*) #_await;
         #_route::Outcome::from(#__req, ___responder)
     }