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Date:   Wed, 5 Sep 2018 21:22:11 +0200 (CEST)
From:   Jan Engelhardt <jengelh@inai.de>
To:     Greg KH <greg@kroah.com>
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Subject: Re: [RFC] UAPI: Check headers by compiling all together as C++
In-Reply-To: <20180905165552.GB25206@kroah.com>
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References: <153616286704.23468.584491117180383924.stgit@warthog.procyon.org.uk> <20180905165552.GB25206@kroah.com>
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On Wednesday 2018-09-05 18:55, Greg KH wrote:

>On Wed, Sep 05, 2018 at 04:54:27PM +0100, David Howells wrote:
>> 
>> Here's a set of patches that inserts a step into the build process to make
>> sure that the UAPI headers can all be built together with C++ (if the
>> compiler being used supports C++).  All but the final patch perform fixups,
>> including:
>
>Wait, why do we care?  What has recently changed to start to directly
>import kernel uapi files into C++ code?

With C++11, C++ has become a much nicer language to use (for userspace, anyway).

>And if userspace wants to do this, can't they do the C namespace trick
>themselves when they do the import?

The only trick is to use an extra C source file and extensively wrap things.