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Subject: Re: Warnings whilst building 5.2.0+
To:     Chris Clayton <chris2553@googlemail.com>,
        "Enrico Weigelt, metux IT consult" <lkml@metux.net>,
        LKML <linux-kernel@vger.kernel.org>, <tglx@linutronix.de>,
        <hpa@zytor.com>
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 <e576372c-fda0-ef9f-346c-3e5c0e5fd4a3@googlemail.com>
From:   John Hubbard <jhubbard@nvidia.com>
CC:     Ingo Molnar <mingo@redhat.com>, "x86@kernel.org" <x86@kernel.org>,
        Borislav Petkov <bp@alien8.de>
Message-ID: <d1413ca8-23e2-3f77-cd57-87b4229627aa@nvidia.com>
Date:   Tue, 6 Aug 2019 23:45:00 -0700
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On 8/6/19 11:30 PM, Chris Clayton wrote:
> On 09/07/2019 12:39, Chris Clayton wrote:
>> On 09/07/2019 11:37, Enrico Weigelt, metux IT consult wrote:
>>> On 09.07.19 08:06, Chris Clayton wrote:
...
>>> Can you check older versions, too ? Maybe also trying older gcc ?
>>>
>>
>> I see the same warnings building linux-5.2.0 with gcc9. However, I don't see the warnings building linux-5.2.0 with the
>> the 20190705 of gcc8. So the warnings could result from an improvement (i.e. the problem was in the kernel, but
>> undiscovered by gcc8) or from a regression in gcc9.
>>
> 
>  From the discussion starting at https://marc.info/?l=linux-kernel&m=156401014023908, it would appear that the problem is
> undiscovered by gcc8. Building a fresh pull of Linus' tree this morning (v5.3-rc3-282-g33920f1ec5bf), I see that the
> warnings are still being emitted. Adding the participants in the other discussion to this one.
> 

The warnings are still there because the fix has not been committed to any
tree yet.

If you could try out my proposed fix [1], and reply to that thread with perhaps a
Tested-by tag, that would help encourage the maintainers to accept it.

So far it hasn't made it to the top of their inboxes, but I'm hoping... :)


[1] https://lore.kernel.org/r/20190731054627.5627-2-jhubbard@nvidia.com
     ("x86/boot: save fields explicitly, zero out everything else")

thanks,
-- 
John Hubbard
NVIDIA