[PATCH 1/5] config/riscv: add flag for using Zbc extension

[Stephen Hemminger]

On Mon, 7 Oct 2024 10:14:22 +0200
Stanisław Kardach <stanislaw.kardach at gmail.com> wrote:

> > > >
> > > > Please do not add more config options via compile flags.
> > > > It makes it impossible for distros to ship one version.  
> That is a problem with RISC-V in general. Since all features are
> "extensions" and there is no limit (up to a point) on the permutation
> of those, we cannot statically build the code for all extensions.
> Fortunately instructions tend to resolve to nops if an instruction is
> not present but that still increases the code size for no benefit on
> platforms without a given extension.

X86 already has the cpu feature flag infrastructure, why not use similar
mechanism on RiscV?