Re: AVX2: how to detect?

[Taylor R Campbell <campbell+netbsd-tech-pkg%mumble.net@localhost>]

> Date: Thu, 17 Aug 2023 16:40:50 +0200
> From: Thomas Klausner <wiz%NetBSD.org@localhost>
> 
> Some package behave differently if they find AVX2 support in the CPU.
> 
> For example:
> 
> http://www.ki.nu/pkgsrc/reports/current/NetBSD-9.0/20230814.0649/qt6-qt3d-6.5.2/install.log
> 
> => Checking file-check results for qt6-qt3d-6.5.2
> ERROR: ************************************************************
> ERROR: The following files are in the PLIST but not in /tmp/graphics/qt6-qt3d/work/.destdir/usr/pkg:
> ERROR:         /tmp/graphics/qt6-qt3d/work/.destdir/usr/pkg/qt6/include/Qt3DCore/6.5.2/Qt3DCore/private/matrix4x4_avx2_p.h
> 
> Does anyone have an idea how to detect this properly for pkgsrc?

Can the code be unconditionally included in the package, and can use
of the code at runtime be conditional on a runtime cpuid test?

If not, is there a configure option for this, so we can make it a
package build option that is default off (particularly for binary
packages which need to work on the least capable CPUs) but allows
people to turn it on if they want?