Re: [Qemu-devel] [PULL 0/8] Python queue, 2019-06-07

[Eduardo Habkost]

On Tue, Jun 11, 2019 at 04:50:34PM +0100, Peter Maydell wrote:
> On Mon, 10 Jun 2019 at 13:58, Peter Maydell <address@hidden> wrote:
> > Hi. This fails to build on one of my buildtest machines:
> >
> > ERROR: Cannot use 'python3', Python 2 >= 2.7 or Python 3 >= 3.5 is required.
> >        Use --python=/path/to/python to specify a supported Python.
> >
> > The machine has python 2.7.6 and 3.4.3. (It's an Ubuntu trusty
> > box; it's one of the gcc compile farm machines so upgrades to its
> > OS are not really under my control.)
> 
> Rereading this, I realise that either the check or the error
> message is wrong here. The machine has 2.7.6, which satisfies
> "python 2 >= 2.7", so we should be OK to build. The bug
> seems to be that we say "prefer python3 over plain python
> on python2" early, but don't revisit that decision if the
> python3 we found isn't actually good enough for us.

Right.  The error message is technically correct, but misleading.
python3 is too old, but python2 would work.

We can make configure not use python3 by default if it's too old,
and fall back to python2 in this case.

-- 
Eduardo