diff --git a/contrib/src/gizmos/splittree.cpp b/contrib/src/gizmos/splittree.cpp
index d5b968f0e6..8dbd9221e4 100644
--- a/contrib/src/gizmos/splittree.cpp
+++ b/contrib/src/gizmos/splittree.cpp
@@ -19,7 +19,7 @@
 // headers
 // ----------------------------------------------------------------------------
 #ifdef __GNUG__
-    #pragma interface "splittree.cpp"
+    #pragma implementation "splittree.h"
 #endif
 
 // For compilers that support precompilation, includes "wx/wx.h".