[PATCH v14 0/9] Add rseq extensible ABI support

[Michael Jeanson]

On 2025-01-07 11:16, Michael Jeanson wrote:
>> I've worked on posting a patch for exposing TLS_TP_OFFSET
>> unconditionally, but the test case for it hits a snag: we still don't
>> have <thread_pointer.h> on all architectures.  I see build failures on:
>>
>>   alpha
>>   arc
>>   arm
>>   mips
>>   s390
>>   s390x
>>   sh
>>
>> Of these, only mips and sh do not yet assume that GCC's
>> __builtin_thread_pointer work.
>>
>> We could disable the new test, but perhaps we should complete the
>> <thread_pointer.h> implementation?  Not sure where this puts us in terms
>> of inclusion in the upcoming release.  I'll try to add a generic
>> <thread_pointer.h> and implementations for mips and sh.
> 
> I agree we should complete the <thread_pointer.h> implementation, I was
> under the impression it was mostly done with my previous patches. I'll
> have a look at the architectures you listed.
> 
> I can do mips and sh if you haven't already started and it saves you
> some time?

I've tried build-many-glibcs.py builds for all the architectures you
mentioned here with your TLS_TP_OFFSET v2 patchset on top of my
updated RSEQ ABI patchset and I had no build failures other than
something weird on mips-n32 where I had to add an include guard
to 'sysdeps/mips/dl-tls.h'.

Is there something different in your environment?

Maybe some older GCC version on some of those architectures
without __builtin_thread_pointer() support?