diff --git a/include/wx/unix/apptrait.h b/include/wx/unix/apptrait.h
index ca2570d55e..5a11f9c3e5 100644
--- a/include/wx/unix/apptrait.h
+++ b/include/wx/unix/apptrait.h
@@ -47,6 +47,7 @@ public:
     virtual int WaitForChild(wxExecuteData& execData);
 #ifdef wxHAS_GUI_CALLBACKS
     virtual int AddProcessCallback(wxEndProcessData *data, int fd);
+#endif
 #if wxUSE_TIMER
     virtual wxTimerImpl *CreateTimerImpl(wxTimer *timer);
 #endif