Re: [PATCH] mmc: Test bus-width for old MMC devices (v2)

Takashi Iwai
2010-12-17T08:11:50Z

At Fri, 17 Dec 2010 03:43:42 +0000,
Chris Ball wrote:
>
> Hi Philip,
>
> On Thu, Dec 16, 2010 at 06:33:49PM -0800, Philip Rakity wrote:
> > It is not possible for bus_width to be not initialized. This would imply ARRAY_SIZE(bus_widths) is 1. Certainly not true.
>
> Right, I agree. We should fix the warning anyway.

Well, this is always a gray-zone question. One prefers fixing it
either via uninitialized_var() or by setting a bogus value. But, this
would cover any possible real bug in future. Thus another prefers
ignoring it, because it's just a compiler bug (mostly of old gcc).

After all, it's up to maintainer, so take as you like :)

thanks,

Takashi

> > We could just initialize by changing
> > + unsigned idx, bus_width;
> > to
> > + unsigned idx, bus_width = 0;
>
> Okay, I've pushed to mmc-next with that change.
>
> > I wonder what compiler are you using so we can avoid this issue in future.
>
> Ah, good point -- I was building with a gcc 4.1.2 ARM cross-compiler,
> and using a gcc 4.5.1 cross-build instead avoids the warning.
>
> Thanks,
>
> --
> Chris Ball <cjb@laptop.org> <http://printf.net/>
> One Laptop Per Child
>