diff --git a/apps/openmw/mwphysics/contacttestresultcallback.hpp b/apps/openmw/mwphysics/contacttestresultcallback.hpp
index bb90eced0..0f469127d 100644
--- a/apps/openmw/mwphysics/contacttestresultcallback.hpp
+++ b/apps/openmw/mwphysics/contacttestresultcallback.hpp
@@ -8,7 +8,7 @@
 #include "../mwworld/ptr.hpp"
 
 class btCollisionObject;
-class btCollisionObjectWrapper;
+struct btCollisionObjectWrapper;
 
 namespace MWPhysics
 {