diff -r 774349a16ba0 -r 1fe3b4ad8caa test/min_cost_arborescence_test.cc
--- a/test/min_cost_arborescence_test.cc	Wed Nov 07 18:13:26 2012 +0100
+++ b/test/min_cost_arborescence_test.cc	Wed Nov 28 12:02:36 2012 +0100
@@ -91,6 +91,7 @@
   Arc e;
   VType c;
   bool b;
+  ignore_unused_variable_warning(c,b);
   int i;
   CostMap cost;
   ArbMap arb;