diff --git a/include/libtorrent/udp_socket.hpp b/include/libtorrent/udp_socket.hpp
index 156d4045b..1be888720 100644
--- a/include/libtorrent/udp_socket.hpp
+++ b/include/libtorrent/udp_socket.hpp
@@ -43,6 +43,7 @@ POSSIBILITY OF SUCH DAMAGE.
 
 #include <deque>
 #include <boost/function/function4.hpp>
+#include <boost/function/function0.hpp>
 
 namespace libtorrent
 {