diff --git a/include/wx/event.h b/include/wx/event.h
index dfb0f59310..2468022efc 100644
--- a/include/wx/event.h
+++ b/include/wx/event.h
@@ -873,7 +873,7 @@ public:
 
 #if defined(__WXDEBUG__) && defined(__WXMSW__)
     // see comments in src/msw/dcclient.cpp where g_isPainting is defined
-    extern int g_isPainting;
+    extern WXDLLEXPORT int g_isPainting;
 #endif // debug
 
 class WXDLLEXPORT wxPaintEvent : public wxEvent