Re: [PATCH] configure: map x32 to cpu_family x86_64 for meson

[David Michael]

On Wed, Jun 9, 2021 at 8:45 AM Daniel P. Berrangé <berrange@redhat.com> wrote:
> On Wed, Jun 09, 2021 at 08:28:39AM -0400, David Michael wrote:
> > The meson.build file defines supported_cpus which does not contain
> > x32, and x32 is not one of meson's stable built-in values:
> > https://mesonbuild.com/Reference-tables.html#cpu-families
> >
> > Signed-off-by: David Michael <fedora.dm0@gmail.com>
> > ---
> >
> > Hi,
> >
> > QEMU fails to build for x32 due to that cpu_family not being defined in
> > supported_cpus.  Can something like this be applied?
> >
> > Alternatively, maybe it could be added to supported_cpus and accepted
> > everywhere that matches x86 in meson.build, but upstream meson does not
> > define a CPU type for x32.
>
> "supported_cpus" serves two distinct purposes in meson.build
>
>  - Identifies whether TCG supports the target
>  - Identifies whether QEMU maintainers consider the target supported
>
> The change proposed below makes x32 be treated the same as x86_64.
>
> Maybe that's right for the question of TCG support, but I'm less
> sure it is right from POV of QEMU maintainers expectations around
> the x32 target status. AFAIK, we don't have any CI for x32 and
> IIUC no maintainers are actively testing it manually, so it ought
> to be in the unsupported category.

Okay, then can something be done to change this line?

https://gitlab.com/qemu-project/qemu/-/blob/master/meson.build#L247

It's what causes the build to fail if it doesn't force the interpreter
due to x32 not being in supported_cpus, but then the following
(unreachable) code expects that x32 is not using the interpreter.

https://gitlab.com/qemu-project/qemu/-/blob/master/meson.build#L263

Thanks.

David