Re: keyspan_pda.c use of keyspan_pda_get_modem_info

[Benny Halevy <bhalevy@panasas.com>]

On Jun. 27, 2008, 7:17 +0300, Greg KH <greg@kroah.com> wrote:
> On Thu, Jun 26, 2008 at 04:23:46PM +0100, Alan Cox wrote:
>>> In these two call sites the callers bail out if
>>> keyspan_pda_get_modem_info return value is < 0
>> I don't think that is what the compiler is warning about.
>>
>> We error on rc < 0
>> We use the returned status on rc >= 0
>>
>> We set the returned status on rc > 0
>>
>> So the rc = 0 case is broken and gcc seems to be correct about that
> 
> Yes, that is correct, fortunatly that function can never return rc = 0,
> so this will not happen in real life.
> 
> But there is really no way the compiler can ever figure that out, so I
> don't blame it for complaining.
> 
> If you want to make a simple patch to make the compiler happy and be
> quiet about the warning, I'll take it.

Cool. I'll send a patch initializing status to 0.
Now, what about the rc == 0 case?
Does it warrant a BUG_ON() if it should ever happen?

Benny

> 
> thanks,
> 
> greg k-h