diff --git a/include/netinet/in.h b/include/netinet/in.h
index 89188c78b40a6fc3fbd1c14187e92938227a1565..4b3f2b0b1592463bdd90e411fe5e6f1b7fd9f858 100644
--- a/include/netinet/in.h
+++ b/include/netinet/in.h
@@ -358,6 +358,7 @@ struct ip6_mtuinfo
 #define IPV6_DONTFRAG           62
 #define IPV6_RECVTCLASS         66
 #define IPV6_TCLASS             67
+#define IPV6_AUTOFLOWLABEL      70
 #define IPV6_ADDR_PREFERENCES   72
 #define IPV6_MINHOPCOUNT        73
 #define IPV6_ORIGDSTADDR        74