build-sys: fix build on Hurd

diff --git a/configure.ac b/configure.ac
index 2366a009de57d8f0f38b3905d5bc42557c5a8a57..1426f54e3b5be114d6d82f6377cef8a5d205e406 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -173,6 +173,7 @@ AC_DEFINE([HAVE_PF_ROUTE],[],[Support for PF_ROUTE])
 , [], [
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <net/if_dl.h>
 ])
 
 AM_CONDITIONAL(HAVE_PF_ROUTE, [ test x"$HAVE_PF_ROUTE" = xyes ])