Re: [PATCH 06/24] gobject-introspection.bbclass: add a class that enables gobject introspection

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Thu, 2016-03-10 at 01:09 +0100, Martin Jansa wrote:
> On Thu, Mar 10, 2016 at 12:52:20AM +0100, Andreas Oberritter wrote:
> > Hello Alexander,
> > 
> > On 09.03.2016 16:01, Alexander Kanavin wrote:
> > > Signed-off-by: Alexander Kanavin <
> > > alexander.kanavin@linux.intel.com>
> > > ---
> > >  meta/classes/gobject-introspection.bbclass | 39
> > > ++++++++++++++++++++++++++++++
> > >  1 file changed, 39 insertions(+)
> > >  create mode 100644 meta/classes/gobject-introspection.bbclass
> > > 
> > > diff --git a/meta/classes/gobject-introspection.bbclass
> > > b/meta/classes/gobject-introspection.bbclass
> > > new file mode 100644
> > > index 0000000..ef51629
> > > --- /dev/null
> > > +++ b/meta/classes/gobject-introspection.bbclass
> > > @@ -0,0 +1,39 @@
> > > +# Inherit this class in recipes to enable building their
> > > introspection files
> > > +
> > > +# This allows disabling introspection support in recipes
> > > +# (and therefore avoiding the use of qemu)
> > > +# if gobject-introspection-data is omitted from DISTRO_FEATURES
> > > and MACHINE_FEATURES.
> > > +EXTRA_OECONF_prepend = "${@bb.utils.contains('COMBINED_FEATURES'
> > > , 'gobject-introspection-data', '--enable-introspection', '-
> > > -disable-introspection', d)} "
> > 
> > testing only DISTRO_FEATURES would be better. If MACHINE_FEATURES
> > gets
> > tested, even though indirectly, I'd expect every recipe inheriting
> > this
> > class to switch to MACHINE_ARCH implicitly.
> 
> I think the idea was to prevent using qemu for MACHINEs without
> support
> in qemu. But I fully agree that causing all recipes which inherit
> this
> bbclass effectively MACHINE_ARCH is even worse.
> 
> DISTRO needs to make sure that all supported MACHINEs have support in
> qemu or disable introspection for all of them.

Remember that bitbake has special knowledge of bb.utils.contains() and
is clever enough to make the checksums depend on "gobject-introspection
-data" being present or not and not the actual complete value.

So we can get the best of both worlds here, you can disable g-i on a
per machine basis yet still enable at the distro level. Recipes don't
become machine specific.

Cheers,

Richard