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

From: Mike Snitzer
Date: Mon Dec 11 2017 - 00:24:48 EST


On Sun, Dec 10 2017 at 9:05pm -0500,
Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> 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