Subject: Re: linux-next: build warning after merge of the btrfs-kdave tree

From: Stephen Rothwell <[email-masked]>
Date: Wed, 7 Dec 2016 09:38:19 +1100

Hi David,

On Mon, 28 Nov 2016 11:02:30 +1100 Stephen Rothwell <[email-masked]> wrote:
>
> After merging the btrfs-kdave tree, today's linux-next build (powerpc
> ppc64_defconfig) produced this warning:
> 
> fs/btrfs/inode.c: In function 'run_delalloc_range':
> fs/btrfs/inode.c:1219:9: warning: 'cur_end' may be used uninitialized in this function [-Wmaybe-uninitialized]
>    start = cur_end + 1;
>          ^
> fs/btrfs/inode.c:1172:6: note: 'cur_end' was declared here
>   u64 cur_end;
>       ^
> 
> Introduced by commit
> 
>   cow_file_range_async ("btrfs: Introduce COMPRESS reserve type to fix false enospc for compression")
> 
> Presumably a false positive because ASSERT(0) panics?

Actually it does not if CONFIG_BTRFS_ASSERT is not set (which it isn't
for the above build), so this is not a false positive.  I am still
seeing this.

-- 
Cheers,
Stephen Rothwell