diff --git a/include/wx/os2/gauge.h b/include/wx/os2/gauge.h
index 5df97b19ae..a4f3ec18a6 100644
--- a/include/wx/os2/gauge.h
+++ b/include/wx/os2/gauge.h
@@ -69,7 +69,7 @@ protected:
     int                             m_nWidth;
     int                             m_nHeight;
 
-    wxSize wxGauge::DoGetBestSize(void) const;
+    wxSize DoGetBestSize(void) const;
 
 private:
     DECLARE_DYNAMIC_CLASS(wxGauge)