On 14/06/2023 05:14, Paul Eggert wrote:
> Thanks for the bug report. I installed the attached patch into coreutils
> on Savannah. It builds on your idea with several other changes:
> 
> * There's a similar issue with cksum.c and pclmul.
> 
> * configure.ac can be simplified, since it seems there's no point
> compiling these instructions if __builtin_cpu_supports doesn't work.
> 
> * This lets us simplify the source code a bit more.
> 
> Please let me know if the attached patch works for you.

__builtin_cpu_supports() looks to have sufficient support in
Arch + compiler versions for our needs, so that's good.

Paul you removed the "avx" check from cksum.c. Was that intended?

> PS. Does the attached cksum.c / pclmul change fix any user-visible
> misbehavior? If so, what should we put into the NEWS file?

We have an illegal instruction issue with cksum under Xen DomU
which may be related, as discussed at: https://bugs.debian.org/1037264

Axel does the attached patch change anything for you?

thanks,
Pádraig