[klibc] [PATCH] build: Define __EXPORTED_HEADER__

[Arnd Bergmann]

On Thursday 24 February 2011, Mike Waychison wrote:
> The kernel header guard to ensure that headers aren't included from
> userland moved in commit 69c8f52b.  This causes the following message to
> be emitted when building klibc (which is designed to use kernel headers
> explicitly):
> 
> /usr/local/src/git/linux-2.6//include/linux/types.h:13:2: warning: #warning "Attempt to use kernel headers from user space, see http://kernelnewbies.org/KernelHeaders"
> 
> In order to silence this warning, make sure we define
> __EXPORTED_HEADERS__ when building klibc userland.
> 
> Signed-off-by: Mike Waychison <mikew at google.com>

Well, klibc uses the kernel headers, but I don't think it's a good idea
to use them directly without make headers_install. Since klibc also
doesn't set -D__KERNEL__, the result should be the same, except that
it makes sure not to use any headers that are meant to be internal.

	Arnd