[Y2038] Question about porting y2038-tests to glibc

[Carlos O'Donell]

On 10/30/20 1:08 PM, Joseph Myers wrote:
> On Fri, 30 Oct 2020, Carlos O'Donell via Libc-alpha wrote:
> 
>> My technical opinion is as follows:
>>
>> * We should be open to expanding what build-many-glibcs.py does,
>>   and providing options to select which operations are carried
>>   out, including new QEMU tests.
>>
>> * Using QEMU user is OK in build-many-glibcs.py, but there may be
>>   false positives due to QEMU emulation of syscalls because of the
>>   host kernel.
>>
>> * Using QEMU system in build-many-glibcs.py is even better, and
>>   would be a gold standard IMO.
> 
> Options for those would be reasonable (they'd need to do the QEMU tests 
> only for the subset of architectures and ABIs supported with QEMU), but 
> getting to a clean baseline for even one of the supported glibc ABIs 
> (thus, if using QEMU user emulation, annotating all the tests that might 
> fail in such a configuration, reliably or randomly, because they use 
> functionality such as threads and signals that's problematic for userspace 
> QEMU - as well as the general matter of execution tests that may not 
> reliably pass for all configurations) would probably be a lot of work.  
> And a clean baseline is much better than needing to track known test 
> failures individually.
 
I agree.

I would accept QEMU usage in build-many-glibcs.py, and I also agree
that such checks must have a clean baseline.

Lukasz, Does this give you enough direction to pursue a solution?

-- 
Cheers,
Carlos.