diff --git a/sys/netinet/libalias/alias_irc.c b/sys/netinet/libalias/alias_irc.c
index e9a8d09e586..5aa80e63cb4 100644
--- a/sys/netinet/libalias/alias_irc.c
+++ b/sys/netinet/libalias/alias_irc.c
@@ -59,6 +59,7 @@ __FBSDID("$FreeBSD$");
 #include <errno.h>
 #include <sys/types.h>
 #include <stdio.h>
+#include <string.h>
 #include <limits.h>
 #endif