Subject: Re: linux-next: build warning after merge of the device-mapper tree

From: Mike Snitzer <[email-masked]>
Date: Mon, 11 Dec 2017 00:24:36 -0500

On Sun, Dec 10 2017 at  9:05pm -0500,
Stephen Rothwell <[email-masked]> wrote:

> Hi all,
> 
> After merging the device-mapper tree, today's linux-next build (powerp
> ppc64_defconfig) produced this warning:
> 
> drivers/md/dm.c: In function '__send_changing_extent_only':
> drivers/md/dm.c:1365:45: warning: 'ti' may be used uninitialized in this function [-Wmaybe-uninitialized]
>   num_bios = get_num_bios ? get_num_bios(ti) : 0;
>                                              ^
> 
> Introduced by commit
> 
>   aecefd4919de ("dm: fix __send_changing_extent_only() to send first bio and chain remainder")
> 
> This looks particularly bad :-(

I worked all weekend on DM code and compiled dm.c probably 30 times,
pretty bizarre that the RHEL7 gcc compiler isn't spewing anything about
this.

Anyway, I just fixed it via rebase (new commit is
6fb0326f0a19dd855bfd748481fd32035770376e).

Thanks,
Mike