From 45b4ef924b30935ca6c7677d3973ef9b64ae762e Mon Sep 17 00:00:00 2001
From: Vladimir Rutsky <vladimir@rutsky.org>
Date: Mon, 1 Feb 2016 00:23:50 +0300
Subject: [PATCH] fix loopback example building with -DNDEBUG

---
 loopback.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/loopback.c b/loopback.c
index 4df4e6b..57c3767 100644
--- a/loopback.c
+++ b/loopback.c
@@ -96,6 +96,7 @@ int main(int argc, char *argv[])
     /* Figure out the size of the underlying block device. */
     err = ioctl(fd, BLKGETSIZE64, &size);
     assert(err != -1);
+    (void)err;
     fprintf(stderr, "The size of this device is %ld bytes.\n", size);
     bop.size = size;