diff --git a/misc/ss.c b/misc/ss.c
index 54635f24..279543cd 100644
--- a/misc/ss.c
+++ b/misc/ss.c
@@ -1318,6 +1318,7 @@ void tcp_show_info(struct nlmsghdr *nlh, struct tcpdiagmsg *r)
 		if (info->tcpi_snd_ssthresh < 0xFFFF)
 			printf(" ssthresh:%d", info->tcpi_snd_ssthresh);
 		
+#if LINUX_VERSION_CODE >= 0x20607
 		if (info->tcpi_rcv_rtt)
 			printf(" rcv_rtt:%g", (double) info->tcpi_rcv_rtt/1000);
 		if (info->tcpi_rcv_space)
@@ -1340,6 +1341,7 @@ void tcp_show_info(struct nlmsghdr *nlh, struct tcpdiagmsg *r)
 				       8000000. / (double) vinfo->tcpv_rtt);
 			}
 		}
+#endif
 	}
 }