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From: Andreas Schwab <schwab@suse.de>
To: Luca Tettamanti <kronos.it@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
       linux-kernel@vger.kernel.org, Greg KH <greg@kroah.com>
Subject: Re: [PATCH 2.6.19-rc1] radeonfb: check return value of sysfs_create_bin_file
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Date: Thu, 12 Oct 2006 17:54:55 +0200
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Luca Tettamanti <kronos.it@gmail.com> writes:

> Il Thu, Oct 12, 2006 at 10:07:26AM +1000, Benjamin Herrenschmidt ha scritto: 
>> On Thu, 2006-10-12 at 01:53 +0200, Luca Tettamanti wrote:
>> > sysfs_create_bin_file() is marked as warn_unused_result but we don't
>> > actually check the return value.
>> > Error is not fatal, the driver can operate fine without the files so
>> > just print a notice on failure.
>> 
>> I find this whole business of must check return value for sysfs files to
>> be gratuitous bloat. There are many cases (like this one) where we don't
>> really care and a printk will just increase the kernel size for no good
>> reason.
>> 
>> Maybe we can have a macro we can use to silence the warning when we
>> don't care about the result ? Can gcc do that ?
>
> Ugly macro:
>
> #define UNCHECKED(func) do { if (func) {} } while(0)

Better, but only marginally:

#define UNCHECKED(func) (void)(func)

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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