$NetBSD: patch-ae,v 1.1 2007/06/30 19:18:47 joerg Exp $

--- change_tracking.hh.orig	2001-04-19 15:51:34.000000000 +0000
+++ change_tracking.hh
@@ -47,11 +47,11 @@ template <class T, class SUM>
 class sum_change_tracking : public change_tracking<T> {
 protected:
 	static SUM s_;
-	void update_sum() { s_.sum_ += change_; }
+	void update_sum() { s_.sum_ += this->change_; }
 public:
 	sum_change_tracking() {};
-	sum_change_tracking(T first) : change_tracking<T>(first) { update_sum(frst); };
-	~sum_change_tracking() { tick_incr(-last_); };
+	sum_change_tracking(T first) : change_tracking<T>(first) { update_sum(this->frst); };
+	~sum_change_tracking() { tick_incr(-this->last_); };
 
 
 	void tick_set(T current) { change_tracking<T>::tick_set(current); update_sum(); };