Current tinderbox regressions (video drivers)

[Michel Dänzer]

On Wed, 2009-02-25 at 17:05 +0100, Matthias Hopf wrote:
> On Feb 24, 09 19:46:24 +0100, Michel Dänzer wrote:
> > On Tue, 2009-02-24 at 13:18 -0500, Chris Ball wrote:
> > >    > EXA: Handle separate alpha maps properly in Composite fallback
> > >    http://cgit.freedesktop.org/xorg/xserver/commit/?id=170cf1270dff38d3cce7f5ba5b940d1c0d70eff5
> > > Driver maintainers:  from this commit onwards, EXA requires you to pass
> > > in -DEXA_DRIVER_KNOWN_MAJOR=3, else it'll fail to build.  If you use
> > > Prepare/FinishAccess, UploadToScratch or ExaOffscreenSwap*, you'll need
> > > to make other changes too.
> 
> There used to be a time where API changes were supposed to be upwards
> and downwards compatible. I grieve for that time.

So do I, in general... Unfortunately, this isn't always possible though.

> Seriously, this change would have been easy to do in a less invasive
> manner by not nuking the hook, but just not using it any more. And by
> adding an additional hook for the new buffer types.

You got that backwards (did anyone actually *look* at the change causing
this before complaining? :}: I removed the UploadToScratch hook because
I had to bump the major version, not the other way around. I had to bump
the major version (and add the #error) because the EXA_PREPARE_* indices
are passed to the driver Prepare/FinishAccess hooks, and some drivers
like radeon(hd) use them as indices into arrays. Without these measures,
the drivers would have continued to build and appeared to work, but
could have broken in subtle ways when overflowing the arrays.


> Enough ranting, radeonhd should be fixed now.

Thanks, I hope you checked the Prepare/FinishAccess hooks for the above
(take a look at my radeon fix).


-- 
Earthling Michel Dänzer           |                http://www.vmware.com
Libre software enthusiast         |          Debian, X and DRI developer