- Hide cctors for singletons

git-svn-id: svn://svn.gna.org/svn/sgpemv2/trunk@644 3ecf2c5c-341e-0410-92b4-d18e462d057c

src/backend/history.hh

@@ -89,6 +89,8 @@ namespace sgpem
 		
   protected:
 	History();			//private constructor.
+	History(const History&);
+	History& operator=(const History&);
 
   private:
 	int             _total_time_elapsed;