[MPlayer-users] Compile with new kernel

[Gábor Lénárt]

On Thu, Jul 31, 2003 at 05:44:43PM +0200, gabucino at mplayerhq.hu wrote:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]

> Gábor Lénárt wrote:
> > Is /usr/include/linux a symlink to the source of Linux kernel?
> > If yes, it's bad. /usr/include/linux should not be a link to the kernel
> > source ...
> This is one of "LGB's All Time Mistakes" that noone should ever listen to :)
> 
> /usr/include/linux: symbolic link to /usr/src/linux/include/linux

Arghh, this is BAD. It shouldn't be done this way!
Why? Because glibc in your system was compiled against another kernel
(in most cases, of course no, if you compile kernel and glibc from source,
but care should be taken in this case, because you should compile both of
glibc and kernel if any of them is replaced), so maybe glibc lacks of
infrastructure that a newer kernel supports. The result can be very bad.
And if you don't beleive me, ask kernel developers. Some developer even
suggest to make kernel headers UNUSABLE for user space purposes, and leave
for glibc to have the correct headers. This way they can save several
macros about testing __KERNEL__ and such.

This is the fact why eg /usr/include/linux/* files are part of libc6-dev
at least on Debian. If you don't do this, you will end at non-compiling
softwares, like fbdev vo compilation problem with newer kernels :)
So you can see the truth now :)

The summarize the problem: since most programs uses libc they must use
header files comes from the kernel libc was compiled against. End of
story :)

- Gábor (larta'H)