Re: [PATCH preview 0/5] rust: allow minimum version of 1.83

[Zhao Liu <zhao1.liu@intel.com>]

> > "enable Rust" supports v1.77 and "enable all devices written in Rust"
> > supports v1.83, correct?
> 
> Both support v1.83 only.  However, if Rust is missing or old, "enable
> all devices written in Rust" will fail compilation (e.g. Kconfig would
> fail for ARM/x86 targets due to unsatisfiable CONFIG_PL011);

In this case, a brand new Rust device (without a corresponding C
version) would be unable to compile on the above platforms which don't
support v1.83. I'm not sure if this is an acceptable limitation or
policy. (Has there been a similar case in history?)

> "enable Rust" will simply pick the C version of the PL011 and HPET devices.

I support this, at least the compatibility with the old QEMU won't be
broken! Then all C devices rewritten in Rust can be covered by this
category.

> > The current vmstate builder is excellent, but I'm concerned it might not
> > land soon. Can we find a compromise?
> 
> Do you think the above would be a good compromise?
 
Overall, I think it's OK (it's not even a compromise).

Thanks,
Zhao