Re: [Qemu-devel] [PATCH] configure: Warn about deprecated hosts

[Peter Maydell]

On 17 March 2017 at 13:19, Thomas Huth <address@hidden> wrote:
> On 17.03.2017 12:52, Peter Maydell wrote:
>> On 17 March 2017 at 11:49, Daniel P. Berrange <address@hidden> wrote:
>>> On Fri, Mar 17, 2017 at 11:08:22AM +0000, Peter Maydell wrote:
>>>> We plan to drop support in a future QEMU release for host OSes
>>>> and host architectures for which we have no test machine where
>>>> we can build and run tests. For the 2.9 release, make configure
>>>> print a warning if it is run on such a host, so that the user
>>>> has some warning of the plans and can volunteer to help us
>>>> maintain the port if they need it to continue to function.
>
> I like your patch! ... but instead of completely aborting with
> "Unsupported host OS" when an unexpected host operating system has been
> detected, I'd maybe only print a warning and continue the configure
> process - in case it is a POSIX-compatible system, there is at least a
> small chance that QEMU can be compiled there.

That code path tries to enable all the Linux specific stuff
(including KVM and linux-user and so on) and puts linux-headers/
on the include path. It seems very unlikely that it will actually
work even if in theory a generic-POSIX OS might be able to build
QEMU somehow.

This kind of tiny-corner-case stuff is exactly why I want
to drop any attempt to build on an OS or architecture we don't
actually know about. The 99.9% probability is that no user of
QEMU has successfully gone down that code path in configure for
anything that isn't Linux; and yet here we are arguing about what
its behaviour should be.

thanks
-- PMM