Re: [Qemu-devel] [RfC PATCH] gtk: switch to gtk3 by default, depricate gtk2.

[Gerd Hoffmann <kraxel@redhat.com>]

  Hi,

> > > +        echo "If it is really your intention to build qemu with gtk2 re-run"
> > > +        echo "configure with --with-gtkabi=2.0."
> > > +        echo ""
> > > +        exit 1
> > >      fi
> > >  fi
> > 
> > I'm not really convinced that we should do this, though. Generally
> > configure should just work with what you have, unless you specifically
> > use options to ask it for a feature.

In general yes.  But our plan is to remove gtk2 support.  And I think it
is better to do this in two steps:  First stop using it by default, with
gtk2 support still being available as backup plan in case there are
regressions[1] when people switch over to gtk3.  Second actually
removing gtk2 support.

My main intention here is to catch cases where people build with gtk2
more or less by accident, something like package build dependencies not
being updated from gtk2 to gtk3 because qemu never demanded it.

> We could just print the message and then set  gtk=no instead of 'exit 1'

Fine with me too.

But in that case people will probably notice it later, when they run
qemu and figure the gtk ui is gone.  Not sure this is better than a
straight build failure.  But at least they should easily find the
warning in the build logs when the start digging why gtk is gone.

cheers,
  Gerd

[1] Not that I expect many problems given that fedora and probably other
    distros too build with gtk3 for a while already.