--- libc/sysdeps/linux/common/bits/in.h
+++ libc/sysdeps/linux/common/bits/in.h
@@ -115,6 +115,9 @@
 #define IPV6_MTU_DISCOVER	23
 #define IPV6_MTU		24
 #define IPV6_RECVERR		25
+#define IPV6_V6ONLY             26
+#define IPV6_JOIN_ANYCAST       27
+#define IPV6_LEAVE_ANYCAST      28
 
 #define SCM_SRCRT		IPV6_RXSRCRT