Re: SIGILL when CPUTYPE set to anyting witjh avx and CFLAGS -O2

> Sometimes this might be best, but usually I compile on a dedicated 
> machine and redistribute to others via local repo.

Ahhh, that would be a good reason not to use native then! :-)

Still, the "show-clang-native-features" does help identify what features
clang things can be enabled on a certain CPU.

> At least my latest SIGILL crashes were caused simply by mismatching 
> target CPU :-( Embarassing... apologies for the noise again.
> I didn't know that skylake-avx512 isn't the sequentially the next-Gen., 
> post SkyLake identifyer, so my assumption that my v6 Xeon would support 
> AVX512 was simply wrong.  Now I know better. And IceLake continues 
> confusion... (some AlderLakes do have PCONFIG, others not, WBNOINVD 
> seems completely mainstream-unavailable and tons of feature-flags/units 
> I never heard before.. (http://instlatx64.atw.hu/)  World isn't getting 
> less complicated...

I haven't had recent experience, but I can well believe it! A few years ago,
I used to chase feature flags with each release, and there were some weird
goings on occasionally. I seem to remember weirdness with BMI at one stage
(around 2014), but that was fixed.

> Will try to reproduce my -march=haswell crahes I initially recognized 
> some months ago and in case it is reproducable, pick up this thread again.

I know this is a bit of a "go-faster-stripes" issue, but what flags do you
use generally?

I know I'm opening myself up to ridicule, but my general cflags on most machines
maps to :

-O2 -pipe -march=native -mtune=native -ftree-vectorize -fstack-protector-strong 
-fno-strict-aliasing -Wl,-znow -Wl,-zrelro

-- some of that added by me, some of it by the FreeBSD build system.

> Happy new year to everybody!

Cheers, and the same to you and everybody else!