-Wredundant-declarations does not like nested extern declarations.

lib/libc/gen/_errno.c

@@ -1,4 +1,4 @@
-/*	$NetBSD: _errno.c,v 1.8 1999/12/10 17:27:28 explorer Exp $	*/
+/*	$NetBSD: _errno.c,v 1.9 2000/12/10 03:52:16 christos Exp $	*/
 
 /*-
  * Copyright (c) 1996 The NetBSD Foundation, Inc.
@@ -38,12 +38,11 @@
 
 #include <errno.h>
 
+#undef errno
+extern int errno;
 
 int *
 __errno(void)
 {
-#undef errno
-	extern int errno;
-
 	return &errno;
 }