--- zzzz-none-000/linux-2.6.32.61/kernel/sysctl.c	2013-06-10 09:43:48.000000000 +0000
+++ ar9-7330-650/linux-2.6.32.61/kernel/sysctl.c	2011-10-21 12:21:44.000000000 +0000
@@ -1846,7 +1846,7 @@
 	if (nlen <= 0 || nlen >= CTL_MAXNAME)
 		return -ENOTDIR;
 	if (oldval) {
-		int old_len;
+		int old_len __maybe_unused__;
 		if (!oldlenp || get_user(old_len, oldlenp))
 			return -EFAULT;
 	}