diff --git a/lemon/base.cc b/lemon/base.cc
--- a/lemon/base.cc
+++ b/lemon/base.cc
@@ -2,7 +2,7 @@
  *
  * This file is a part of LEMON, a generic C++ optimization library.
  *
- * Copyright (C) 2003-2008
+ * Copyright (C) 2003-2009
  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
  * (Egervary Research Group on Combinatorial Optimization, EGRES).
  *
@@ -23,7 +23,7 @@
 #include<lemon/core.h>
 namespace lemon {
 
-  float Tolerance<float>::def_epsilon = 1e-4;
+  float Tolerance<float>::def_epsilon = static_cast<float>(1e-4);
   double Tolerance<double>::def_epsilon = 1e-10;
   long double Tolerance<long double>::def_epsilon = 1e-14;