Bug#320515: bug confusion?
As far as I understand, #318979 caused xorg-x11 to FTBFS on sparc because it
included <asm-sparc/fbio.h> which used __user but failed to include
<linux/compiler.h> where __user was defined. This was apparently fixed in
linux-kernel-headers_2.6.13+0rc3-1. So, #318979 is no longer a problem.
What Adeodato is saying is that xorg-x11 will again FTBFS if it is uploaded
before *this* bug (#320515) is fixed. And, because xorg-x11 has never
successfully built on sparc, a number of packages that are waiting on it to
build (kde having the biggest dependency chain) cannot yet be uploaded for
the gcc 4.0 transition.
So, you can forget about bug #318979.