diff --git a/tests/testprec.h b/tests/testprec.h
index ba2cf67c56..3342bb01a8 100644
--- a/tests/testprec.h
+++ b/tests/testprec.h
@@ -29,6 +29,8 @@ class TestAssertFailure { };
 
 // these functions can be used to hook into wxApp event processing and are
 // currently used by the events propagation test
+class WXDLLIMPEXP_FWD_BASE wxEvent;
+
 typedef int (*FilterEventFunc)(wxEvent&);
 typedef bool (*ProcessEventFunc)(wxEvent&);