https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111768
Alexander Monakov <amonakov at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |amonakov at gcc dot gnu.org --- Comment #7 from Alexander Monakov <amonakov at gcc dot gnu.org> --- I'm afraid hybrid CPUs with varying ISA feature sets are not practical for the current ecosystem: you wouldn't be able to reschedule from a higher- to lower-capable core. Not to mention scenarios like Mesa on-disk llvmpipe shader cache. "Always" probing all cores is a not a good idea (the compiler would have to manually reschedule itself to all cores, of which there could be hundreds). Plus, portable API for such probing across available cores does not exist afaik. I think releasing an x86 hybrid CPU with varying capabilities across cores would require substantial preparatory work in the kernel and likely in the userland as well, so probably best to leave it until the time comes and specifics of what can differ are known.