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Re: Portability fix in kern_ntptime.c

On 06.06.2019 05:07, Mouse wrote:
>> Unfortunately, if "undefined behavior" (UB) is invoked, you simply
>> cannot claim to understand what is happening, because C11-compliant
>> compilers have a lot of leeway in what code they generate when
>> behavior is undefined.
> Compilers that do unexpected things under such circumstances are
> extremely poor choices for building kernels.  The kernel is not, and
> a few parts of it cannot be, fully portable code in the C, or even
> POSIX, sense.
> Since IIRC the NetBSD kernel does not even try to be buildable with
> more than a few (two? three?) C implementations, I think it is entirely
> reasonable to speak of understanding the code's behaviour in many cases
> when it is, formally, undefined.

That's why I proposed to paper over it and switch to defined constructs
in this case.

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