[PATCH] Fix linux/stddef.h coordination with glibc (Bug 20215)

[Mikko Rapeli]

On Tue, Jun 07, 2016 at 05:55:05AM -0400, Carlos O'Donell wrote:
> Denys,
> 
> In recent linux 4.6.0 headers we have this:
> 
> git blame include/uapi/linux/stddef.h
> ~~~
> 607ca46e (David Howells  2012-10-13 10:46:48 +0100 1) #include <linux/compiler.h>
> 283d7573 (Denys Vlasenko 2016-03-30 00:14:57 +0200 2) 
> 283d7573 (Denys Vlasenko 2016-03-30 00:14:57 +0200 3) #ifndef __always_inline
> 283d7573 (Denys Vlasenko 2016-03-30 00:14:57 +0200 4) #define __always_inline inline
> 283d7573 (Denys Vlasenko 2016-03-30 00:14:57 +0200 5) #endif
> ~~~
> 
> The definition of __always_inline breaks certain header include
> ordering between glibc and linux headers.
> 
> Mikko,
> 
> I'm curious if your header include fuzzing script caught this failure?

I've seen this, but by default it is only a warning. I have not dared to
run my kernel headers tests with warnings-as-errors since there are so many of
them, and there are plenty of simple errors to fix first.

-Mikko