Jeremie Courreges-Anglas:

> Feedback from other porters would be welcome.

Speaking as somebody who has added support to a few ports for
detecting AArch64 instruction set extensions with the CPU_ID_AA64ISAR0
sysctl(), I think having elf_aux_info() and AT_HWCAP compatible
with FreeBSD would be helpful.  Third-party software out there
frequently supports Linux (getauxval), FreeBSD (elf_aux_info), and
Darwin.  Being able to just ride on the existing FreeBSD support
would save porters the work of adding and upstreaming OpenBSD's own
bespoke solution.

Apart from AArch64, PowerPC64 may also profit from this.  One FreeBSD
porter has been very active in pushing FreeBSD support for PowerPC64
instruction extensions (VSX) upstream.

-- 
Christian "naddy" Weisgerber                          naddy@mips.inka.de