GLXPixmap and radeon driver

Glynn Clements glynn at
Wed Apr 2 08:44:05 PDT 2008

Michel Dänzer wrote:

> > 2. Is there anything which it can do to determine that it can't use a
> > GLXPixmap (without terminating the program)?
> It could catch the error,

The code already checks all return values. The problem is that
glXMakeCurrent() doesn't just return false and generate an X error, it
terminates the program.

Actually, the symptoms suggest that this would have to be a
client-side (libGL) issue, and the specific driver is only triggering
the bug.

> or maybe check for GLX >= 1.3 or something
> like that.

AFAICT, GLX Pixmaps are GLX 1.0. They certainly work with some
implementations which claim GLX 1.2 (e.g. the "nv" driver and Cygwin's
XWin.exe), but other implementations (i.e. the "radeon" driver) die.

In any case, glXCreateGLXPixmap() is returning a valid XID. The
problem only occurs if you try to use it.

> > 3. Is this a known issue which has since been fixed in a later version
> > of the driver (or some other part of X)?
> It'll only be fixed with drivers that support DRI2, don't hold your
> breath. :}

BTW, I'm not concerned with having GLX Pixmaps actually working. I
just need to be able to test whether or not they can be used without
killing the application.

As it stands, we're having to disable the use of GLX Pixmaps on *all*
systems because any attempt to discover whether or not they can be
used might kill the application.

Glynn Clements <glynn at>

More information about the xorg mailing list