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From: Alexander Monakov <amonakov@ispras.ru>
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Subject: Re: open issues
Date: Wed, 30 Aug 2017 22:37:44 +0300 (MSK)
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On Wed, 30 Aug 2017, Rich Felker wrote:
> Great find. I wonder if compiler/diagnostic tool ppl are aware of this
> extension to the C language that XSI imposes. It definitely affects
> things like UBSan, and of course compilers' optimization based on
> assumptions that UB doesn't happen.

If musl is going to use this throughout the implementation, I think it
should be documented somewhere: it's of course fair game to use this
guarantee in implementation of interfaces that are themselves XSI-shaded,
but using it to implement more basic interfaces is less obviously so.

Alexander