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Message-ID: <1504741330.7546.6.camel@perches.com>
Subject: Re: [PATCH] gpio: acpi: work around false-positive
 -Wstring-overflow warning
From: Joe Perches <joe@perches.com>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Hans de Goede <hdegoede@redhat.com>,
        Wei Yongjun <weiyongjun1@huawei.com>, linux-gpio@vger.kernel.org,
        ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Date: Wed, 06 Sep 2017 16:42:10 -0700
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On Wed, 2017-09-06 at 21:53 +0200, Arnd Bergmann wrote:
> On Wed, Sep 6, 2017 at 5:52 PM, Joe Perches <joe@perches.com> wrote:
> > On Wed, 2017-09-06 at 17:47 +0200, Arnd Bergmann wrote:
> > > As suggested by Andy, this changes the format string to have a fixed length.
> > > Since modifying the range check did not help, I also opened a bug against
> > > gcc, see link below.
> > 
> > The code has
> > 
> >         int pin
> > 
> > does changing pin to unsigned int matter?
> 
> No difference, see also the gcc bugzilla report.

Perhaps the bug report does not apply here as the
function is casting a unsigned int to an int through
a pointer when the int could now be negative, the int
is tested for < 256 and is then printed.