Index: lib/boost_1_56_0/boost/polygon/polygon_set_data.hpp
===================================================================
--- lib/boost_1_56_0/boost/polygon/polygon_set_data.hpp	(revision 374)
+++ lib/boost_1_56_0/boost/polygon/polygon_set_data.hpp	(working copy)
@@ -209,6 +209,7 @@
         return;
       }
       int wmultiplier = (winding == COUNTERCLOCKWISE) ? 1 : -1;
+      wmultiplier *= is_hole ? -1 : 1;
       dirty_ = true;
       unsorted_ = true;
       while (vertex0 != end_vertex) {