[Mesa-dev] Lets talk about autotools

[Chuck Atkins]

First, I'm fully in support of killing off autotools woo-hoo to that.  And
given the substantial investment already put into the meson build that
certainly seems like a good direction to go.

That being said, the way "auto" is currently implemented leaves quite a bit
to be desired.  One of the nice features of the Autotools build was how
auto-enabled options were treated in that the dependencies were searched
for and if they were all found and met then the option would be enabled.
My experience so far with the meson build has shown this not to be the case
and a "configure" with no options has yet to be successful for me.  Many of
the 'auto' options are treated as 'set to true if your platform supports
it' regardless of whether your system has the requisite dependencies
available.  For example"

   - The 'gallium-va' option defaults to 'auto' but the implementation ends
   up setting the '_va' option to true if the other option conditions are met,
   long before libva is searched for.  So then when libva isn't found one gets
   an error.
      - if set to auto then missing the libva dependencies should be a
      failure, it should just disable the gallium va state tracker
      - The platform options set to 'auto'  has a set of checks to
   determine which platforms are enabled as required.  If the
   system_has_kms_drm check is true then Wayland is enabled as required.
   Later if the check for wayland dependencies fails, an error occurs.
      - If platforms are set to auto then a failure to locate dependencies
      for a given platform should disable the platform.

I realize these are just two specific examples, each of which can be
readily dealt with in their own specific way so I'm not asking "how to I
address #1 and #2?" because I can certainly do that.  These are just two
instances of many though in the way "auto" is dealt with.  My point is
really a broader one that before meson becomes the primary build then the
behavior of "auto" should create a successful configure out of the box
without additional options.

----------
Chuck Atkins
Staff R&D Engineer, Scientific Computing
Kitware, Inc.


On Tue, Sep 18, 2018 at 9:04 AM Eric Engestrom <eric.engestrom at intel.com>
wrote:

> On Monday, 2018-09-17 17:25:36 -0400, Marek Olšák wrote:
> > Where do I find default values for meson configure options?
>
> If you mean the project's options, they're in meson_options.txt;
> currently not printed in the output of `meson configure` though.
>
> If you mean Meson's own options (like `buildtype`), I don't think that
> information exists anywhere outside of Meson's source code (and it's
> affected by meson.build too).
>
> It might be worth opening an issue upstream to ask for and track the
> progress of this feature if you want it :)
>
> >
> > Thanks,
> > Marek
> >
> > On Mon, Sep 17, 2018 at 12:44 PM, Dylan Baker <dylan at pnwbakers.com>
> wrote:
> > > I feel like for !windows meson is in good enough shape at this point
> that we
> > > can start having the discussion about deleting the autotools build.
> So, is there
> > > anything left that autotools can do that meson cannot (that we
> actually want to
> > > implement)? And, what is a reasonable time-table to remove the
> autotools build?
> > > I think we could reasonably remove it as soon as 18.3 if others felt
> confident
> > > that it would work for them.
> > >
> > > Dylan
> > >
> > > _______________________________________________
> > > mesa-dev mailing list
> > > mesa-dev at lists.freedesktop.org
> > > https://lists.freedesktop.org/mailman/listinfo/mesa-dev
> > >
> > _______________________________________________
> > mesa-dev mailing list
> > mesa-dev at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/mesa-dev
> _______________________________________________
> mesa-dev mailing list
> mesa-dev at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/mesa-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/mesa-dev/attachments/20180918/ae39012a/attachment.html>