Re: [PATCH -tip] sdhci: 'scratch' may be used uninitialized

From: Ingo Molnar
Date: Wed Oct 01 2008 - 04:35:55 EST



* Steven Noonan <steven@xxxxxxxxxxxxxx> wrote:

> On Wed, Oct 1, 2008 at 1:14 AM, Steven Noonan <steven@xxxxxxxxxxxxxx> wrote:
> > - u32 scratch;
> > + u32 uninitialized_var(scratch);
>
> A bit of a further explanation:
>
> The variable 'scratch' is always initialized before it's used. The
> conditional which is responsible for initialization of 'scratch' will
> always evaluate 'true' when the first loop iteration occurs, and thus,
> it's properly initialized. GCC doesn't see this, of course, so using
> the uninitialized_var() macro seems to work for silencing this case.

another small workflow suggestion: when you add explanation for the
changelog it's better to just include the updated patch (dont worry
about the duplication) - that way maintainers dont have to cut&slice the
patch and the description toghether. [which is not just a matter of
wasting time, but if you do tons of patch juggling, it becomes a real
risk factor.]

Ingo
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