Re: [Dri-devel] trunk: Patch to let it compile under Linux 2.5.42+ (input layer overhaul)

[Benjamin H. <be...@ke...>]

>So if you get a "new" kernel it goes to /usr/src/linux-x.x.xx with a symlink 
>to /usr/src/linux and then you have to setup the (three) symlinks under 
>/usr/include.
>
>/usr/include> l asm*
>lrwxrwxrwx    1 root     root           26 Okt  6 04:50 asm -> 
>/usr/src/linux/include/asm
>lrwxrwxrwx    1 root     root           34 Okt  6 04:50 asm-generic -> 
>/usr/src/linux/include/asm-generic
/usr/include> l linux
>lrwxrwxrwx    1 root     root           28 Okt  6 04:50 linux -> 
>/usr/src/linux/include/linux
>
>Worked for ages.

Well, maybe, but it has always been the wrong thing to do,
at least according to Linus, and this have been more of
a problem with recent kernels. Some reasons are userland
abuse of inline function declared in kernel headers, others
are possibly type pollution, and finally, the simple fact
that your glibc headers aren't just supposed to work with
different kernel headers than the ones this glibc was
built with (oh well....)

Linus have been very clear about that several times. The
"kernel" headers bundled by glibc in /usr/include/asm,
/usr/include/linux/ etc... are "cooked" by the glibc
folks they may not (and are probably not anymore) the
exact kernel headers of a given kernel snapshot.

If you need access to real up-to-date kernel headers,
you'd rather go look at the symlink in
/lib/modules/kernel_version/build if it exist, or ask
the user (eventually fallback to /usr/src/linux).

Ben.