[klibc] [PATCH] build: Define __EXPORTED_HEADER__

[Arnd Bergmann]

On Monday 28 February 2011, Mike Waychison wrote:
> How is one expected to test if the files should be rebuild or not?
> Forcing a headers_install as part of a build will cause the entire
> userland to be rebuilt.

How about changing headers_install to only install files that have
changed? Make headers_install alreadh knows the list of all files
it is installing.

	Arnd