[RFC PATCH 1/8] RISC-V: Minimal support of bitmanip extension

[Kito Cheng]

> > That's a good point, but ISA_SPEC_CLASS_FROZEN_2021 is hard to
> > reference to which spec, so I would prefer to add a -misa-spec=2021 to
> > align platform/profile spec, and then ISA_SPEC_CLASS_2021, and before
> > RISC-V platform/profile spec has released, let keep
> > ISA_SPEC_CLASS_NONE :p
>
> For sure we cannot reference a spec that is not frozen yet (i.e.
> platform/profile).
> ISA_SPEC_CLASS_FROZEN_2021 was a proposal for all groups of ISA extensions
> that have been frozen in 2021 (zb*, zk*, etc.) and will eventually be ratified.
> But yes, keeping NONE until the specifications are ratified and change
> the specification
> class then is also possible.

I expect those specs can be ratified at the end of this year, and then
we still have a few months
to update before GCC 12 release.