https://bugs.gentoo.org/828901
--- a/strnstr.c
+++ b/strnstr.c
@@ -38,7 +38,6 @@
 #if defined(LIBC_SCCS) && !defined(lint)
 static char sccsid[] = "@(#)strstr.c	8.1 (Berkeley) 6/4/93";
 #endif /* LIBC_SCCS and not lint */
-#include <sys/cdefs.h>
 
 #include <string.h>
 
--- a/whois.c
+++ b/whois.c
@@ -43,7 +43,6 @@
 #endif /* not lint */
 #endif
 
-#include <sys/cdefs.h>
 #ifdef __FBSDID
 __FBSDID("$FreeBSD: /repoman/r/ncvs/src/usr.bin/whois/whois.c,v 1.43.2.1 2006/01/31 18:11:21 jhay Exp $");
 #endif