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SubjectRe: [PATCH] sched: Work around undefined behavior in sched class checking
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On 5/5/2021 9:41 AM, Nick Desaulniers wrote:
> On Wed, May 5, 2021 at 7:39 AM Andi Kleen <ak@linux.intel.com> wrote:
>>> Would you please provide a
>>> minimal test case?
>> You can only reproduce it with a LTO build because it needs knowledge
>> between different translation units for this specific case.
>>
>> But gcc will totally do the optimization even without LTO if it can
>> prove the same inside a single TU.
> It would be helpful to isolate a test case that doesn't rely on LTO,
> if possible.

Like I wrote earlier we used to see it all the time in __pa_symbol
before it used RELOC_HIDE. I bet if you make RELOC_HIDE a nop you'll see
multiple instances.

But not sure why you want a test case?

-Andi

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