diff --git a/src/ketos/structs.rs b/src/ketos/structs.rs
index 1111e68d9..f2c126927 100644
--- a/src/ketos/structs.rs
+++ b/src/ketos/structs.rs
@@ -113,7 +113,7 @@ impl<T: StructValue> ForeignStructDef<T> {
     fn get_rc(&self, value: Value) -> Rc<T> {
         match value {
             Value::Foreign(fv) => {
-                ForeignValue::downcast_rc::<T>(fv)
+                <dyn ForeignValue>::downcast_rc::<T>(fv)
                     .expect("invalid foreign value for ForeignStructDef")
             }
             _ => panic!("invalid value for ForeignStructDef")