Building DRI-disabled drivers with DRI-enabled xserver

[Matt Turner]

Hi,

It seems impossible currently to build DDXs with --disable-dri against
an X server built with DRI. The X server's xorg-server.h file defines
XF86DRI, which is included by the DDX's config.h files.

In config.h, if --enable-dri is passed, XF86DRI is defined to 1. With
--disable-dri, /* #undef XF86DRI */ is added, which doesn't negate the
definition provided by xorg-server.h, and causes build failures later
on.

Is this intended? We've had a bug about it in Gentoo for a while [1]
and it seems to cover xf86-video-{tdfx,sis,ati,intel,mga,r128,savage}.

The autoconf manual [2] seems to say there's no way to put #undef XXX
into config.h. What's the solution here?

Thanks,
Matt

[1] https://bugs.gentoo.org/show_bug.cgi?id=266087
[2] http://www.gnu.org/s/hello/manual/autoconf/Header-Templates.html