[Pixman] [PATCH] Fix server crash in pixman (to be discussed)

[Soeren Sandmann]

Matthias Hopf <mhopf at suse.de> writes:

> > This patch in particular, I don't think shold ship with no testing at
> > all. So please revert it, and we can consider it again for 0.19.x.
> 
> I'm fine with that if you consider it problematic. Given that the
> situation it changes should actually not occur at all, I doubt there's
> any fallout, though.

I do consider it problematic. Thanks for reverting it.

> > - Why are you seeing an assert in the first place? 
> > 
> >   The asserts have been disabled since 0.16.4/0.17.6 because pixman
> >   shouldn't take down the X server with asserts for things that would
> >   otherwise be harmless.
> 
> Apparently we're still using 0.16.0 in SLE11SP1. So that explains.
> I double checked that there were no related changes in the region code
> before fixing.
> 
> However, what happens if the code would have been compiled with -NDEBUG?
> Is the code path stable with empty regions? If it is, it can be argued
> that the patch is not necessary, but it could also be argued that the
> assert() shouldn't have been there in the first place.

Who knows? Who knows if it's stable even *with* the patch? That's why
I don't want it in for 0.18.0.

> >   If you are using an older version than those in SLES, then you might
> >   want to either upgrade to 0.16.4, or backport
> 
> No chance. We are version and feature freeze for quite some time now.
> Time cycles are much different in enterprise products :-/
> Especially in SLE11SP1, as changes to SLE11 should be as minimal as
> possible (and SLE11 is over a year old).
> 
> >        ec6de472d042bec05aaa53f9d14bfbe23edbe01e
> 
> That sounds more realistic. However, we don't have any other issues with
> assert()s, and there is a slim chance that this backport introduces
> additional regressions (asserts with side effects etc.).

If it were *my* enterprise product, I'd definitely get rid of the
assertions, because they are known to take down the X server in
various situations. That's your call of course.

As of 0.17.6 the assertions are not even enabled in unstable releases
because the only result were that they get triggered by the same old X
server issues, which just causes people to not test the pixman
releases.


Soren