port-amd64/59551: openssl/libcrypto build fails with MKLLVM=yes (unsupported AVX-IFMA instructions)

[sotiris%lamprinidis.com@localhost]

>Number:         59551
>Category:       port-amd64
>Synopsis:       openssl/libcrypto build fails with MKLLVM=yes (unsupported AVX-IFMA instructions)
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-amd64-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jul 24 17:30:00 +0000 2025
>Originator:     Sotiris Lamprinidis
>Release:        netbsd-current-20250719
>Organization:
>Environment:
NetBSD arm64 10.1_STABLE NetBSD 10.1_STABLE (GENERIC64.20250628095823Z) #0: Mon Jun 30 01:58:42 UTC 2025  builds%b3.aoa.netbsd.org@localhost:/home/builds/ab/netbsd-10/evbarm-aarch64/20250628095823Z-obj/home/source/ab/netbsd-10/src/sys/arch/evbarm/compile/GENERIC64 evbarm
>Description:
Cross building for amd64-x86_64 from evbarm-aarch64 fails on external/apache2/openssl/lib/libcrypto:
  
/usr/src/crypto/external/apache2/openssl/lib/libcrypto/arch/x86_64/rsaz-2k-avxifma.S:86:1: error: unsupported instruction                                                                         
{vex} vpmadd52luq 0(%rsi),%ymm1,%ymm3                                                                                                                                                             
^       
[...]

This file was recently added during an update of openssl: https://mail-index.netbsd.org/source-changes/2025/07/17/msg157468.html

Seems like AVX-IFMA was introduced in clang 16 (https://releases.llvm.org/16.0.0/tools/clang/docs/ReleaseNotes.html)?

This _should_ error on a native build, too. I will try a native build and follow up.
>How-To-Repeat:
build.sh command:    /usr/src/build.sh -ax86_64 -mamd64 -Bvanilla-llvm-202507241328CEST -D/home/sl/build/amd64-x86_64-vanilla-llvm/dest -O/home/sl/build/amd64-x86_64-vanilla-llvm/obj -R/home/sl/build/amd64-x86_64-vanilla-llvm/release -T/home/sl/build/amd64-x86_64-vanilla-llvm/tools -V TMPDIR=/tmp -V MAKECONF=/dev/null -V MKDEBUG=yes -U -u -j8 -cclang release
>Fix: