Re: 2.6.14 assorted warnings

[Arnd Bergmann]

On Freedag 28 Oktober 2005 09:30, Dave Jones wrote:
> gcc is dumb, it doesn't realise that the variable will be filled by another
> function if its passed thus..
> 
>         unsigned long foo
>         bar(&foo)
>         if (foo==1)
>                 ...
> 
> With bar() filling in content of foo.
> I believe there's at least once instance of this in gcc bugzilla.
> 
The case is more complicated here. gcc before 4.0 always assumed that
bar(&foo); initializes foo. gcc-4.0 now looks into bar if it is inlining
that and tries to find out if that really initializes foo in every
case.

In the example, bvec_alloc_bs does not initialize &idx when nr is not
between 1 and BIO_MAX_PAGES, so gcc is telling the truth here.

	Arnd <><
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