Re: rapidfuzz failing 9.0 i386 2023Q2

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

> Date: Mon, 03 Jul 2023 08:55:20 -0400
> From: Greg Troxel <gdt%lexort.com@localhost>
> 
> It's not about the build cpu at all.  pkgsrc uses the base compiler, and
> on i386 NetBSD supports 486 and up, so the gcc config is:
> 
>   Target: i486--netbsdelf
> 
> and thus avx2 is not available.

That doesn't follow -- you can enable per-file or per-function AVX2
support with -mavx2 or __attribute__((target("avx2"))) or similar.

> The point is that i386 fails to imply avx2, and thus it can't just be
> used.
> 
> It is totally fair to say that it should be probed for and used at
> runtime, regardless of build target.  But it does not seem to do that.

It does appear to do that; there's a bunch of logic to query cpuid,
translate that into feature bits of which one is AVX2, and use that in
some places.

> Right now, there are on the order of 500 failed packages in i386 bulk
> builds for 2023Q2, and that's a big problem.  Failure to use avx2 on
> i386 is a very minor problem.  So I'm going to commit a minimal change
> "don't expect avx2" for i386 and request a pullup.

Sure, that's fine, no objection here.