Continuing the UAPI split

[Florian Weimer]

* Carlos O'Donell:

> On 11/7/19 3:32 PM, Florian Weimer wrote:
>> * Carlos O'Donell:
>> 
>>> On 11/7/19 11:21 AM, Szabolcs Nagy wrote:
>>>>> Or just giving up and telling users they can't just directly include
>>>>> both libc headers and kernel headers?
>>>>
>>>> including both libc and linux headers is fragile and
>>>> will break differently across the different linux
>>>> libc implementations.
>>>
>>> We saw this all the time working in embedded.
>> 
>> Do you mean you saw problems while you working in the embedded space?
>  
> Yes, embedded Linux to be specific.
>
> There is a strong coupling between the kernel version and the toolchain
> version, specifically because the strategies we take to solve these
> problems end up being brittle in this regard.
>
> Too new a kernel and you get new header problems not solved by your
> old libc. Too new a libc and the kernel doesn't have the header
> coordination fixes required for the newer software that needed the
> newer libc.
>
> Does that clarify my point?

Yes, it does.  It wasn't clear to me if you wanted to say that this
was actually working for the embedded case.