diff --git a/src/unix/linux_like/mod.rs b/src/unix/linux_like/mod.rs
index 2b8107da17a2da36c6a03592a08695c41c008d9c..b5c029e79696db0102fb1c1e7733932ff01dd21d 100644
--- a/src/unix/linux_like/mod.rs
+++ b/src/unix/linux_like/mod.rs
@@ -835,7 +835,6 @@ pub const IPV6_V6ONLY: ::c_int = 26;
 pub const IPV6_JOIN_ANYCAST: ::c_int = 27;
 pub const IPV6_LEAVE_ANYCAST: ::c_int = 28;
 pub const IPV6_MULTICAST_ALL: ::c_int = 29;
-pub const IPV6_ROUTER_ALERT_ISOLATE: ::c_int = 30;
 pub const IPV6_RECVPKTINFO: ::c_int = 49;
 pub const IPV6_PKTINFO: ::c_int = 50;
 pub const IPV6_RECVTCLASS: ::c_int = 66;