diff --git a/lib/roken/strcasecmp.c b/lib/roken/strcasecmp.c
index 5e25ad140..12a51a1d2 100644
--- a/lib/roken/strcasecmp.c
+++ b/lib/roken/strcasecmp.c
@@ -40,7 +40,9 @@ RCSID("$Id$");
 #ifdef HAVE_SYS_TYPES_H
 #include <sys/types.h>
 #endif
+#ifdef HAVE_SYS_CDEFS_H
 #include <sys/cdefs.h>
+#endif
 
 #if defined(LIBC_SCCS) && !defined(lint)
 static char sccsid[] = "@(#)strcasecmp.c	8.1 (Berkeley) 6/4/93";