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Date:   Wed, 20 Sep 2023 14:08:57 -0700
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Subject: Re: arch/m68k/include/asm/raw_io.h:91:13: warning: array subscript 0
 is outside array bounds of 'volatile u16[0]' {aka 'volatile short unsigned
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To:     Rob Herring <robh@kernel.org>
Cc:     kernel test robot <lkp@intel.com>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
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        Wim Van Sebroeck <wim@linux-watchdog.org>
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From:   Guenter Roeck <linux@roeck-us.net>
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On 9/20/23 09:20, Rob Herring wrote:
[....]

>>
>> Sure, but I still argue that this isn't worth it for drivers like this one.
>> Are you going to submit a fix ? Because otherwise I'll submit a patch
>> to drop COMPILE_TEST from MACHZ_WDT.
> 
> I honestly don't know what the fix is. There's a compiler flag to
> allow 0 address, but that seems like a big hammer. From what I read on
> the fix for gcc-12, we shouldn't be getting this, but I haven't
> confirmed. I was hoping for comment from Geert as the issue doesn't
> appear to be the driver, but the arch code.
> 
> Furthermore, I just built the same HEAD and config as reported and
> don't see this error. I'm using kernel.org nolibc gcc 13.2.0 which
> should be the same version.
> 

Exactly my point. So now we are stuck with a report like this on a
driver which probably has 0 users and we don't know how to fix it,
all to get the benefit of being able to compile it for an architecture
and platform which will never use it.

I seem to recall similar errors with m68k and COMPILE_TEST last time
I tried to enable it on watchdog drivers, so I am not sure if this is
entirely new.

Guenter