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Date: Fri, 25 Feb 2011 13:11:00 +0100
From: Andreas Oberritter <obi@opendreambox.org>
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Subject: Re: linux-libc-headers version (reloaded)
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On 02/25/2011 08:51 AM, Khem Raj wrote:
> Well one way is to have kernel headers per machine which means you can
> not share target packages anymore since they have to build per machine
> but it would be much integrated solution and we could generate the
> kernel headers from the kernel recipe itself so we are sure that the
> .config of kernel headers match the .config of  kernel itself
> downside is it will defeat the multimachine sharing packages a bit.

The .config does not have any influence on the generated
linux-libc-headers by definition. linux-libc-headers must not contain
any CONFIG_* statements, because they are meant to be independent of it.
The kernel config is not available to linux-libc-headers after all.

The point I was trying to make is that feature detection at compile time
is impossible, if the feature can be disabled by the kernel config
(which is the case for epoll and inotify, which in turn were the
examples discussed on the mailing list in May 2010). You need to do
runtime tests in programs intended to be portable.

Regards,
Andreas