--- src/net/socket_fd.cc.orig	2018-10-27 17:52:05.000000000 -0700
+++ src/net/socket_fd.cc	2018-10-27 18:21:17.000000000 -0700
@@ -71,9 +71,14 @@
   int opt = p;
 
   if (m_ipv6_socket)
+#if defined(IPV6_TCLASS)
     return setsockopt(m_fd, IPPROTO_IPV6, IPV6_TCLASS, &opt, sizeof(opt)) == 0;
+#else
+    //do nothing
+    ((void)0);
+#endif
   else
-    return setsockopt(m_fd, IPPROTO_IP, IP_TOS, &opt, sizeof(opt)) == 0;
+  return setsockopt(m_fd, IPPROTO_IP, IP_TOS, &opt, sizeof(opt)) == 0;
 }
 
 bool