Am Di., 27. Okt. 2020 um 03:31 Uhr schrieb John Cowan <xxxxxx@ccil.org>:
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> On Mon, Oct 26, 2020 at 9:17 PM Wolfgang Corcoran-Mathe <xxxxxx@sigwinch.xyz> wrote:
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>> This would be undefined behavior in C89, but, after a lot of
>> searching, it does seem that type-punning through unions is valid in
>> C99 (and C11, allegedly; I don't have a copy of that standard).
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> And a Good Thing Too, since people have been using them since time immemorial.
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>> So if a C99 sample implementation would be SRFI-acceptable, I'll
>> start work on this shortly.
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> It would be.
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>> What about make-nan ?  Many reviewers have requested it, and we're
>> now in a position to provide it.
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> I think we should provide it, yes:  double make_nan(_Bool quiet, long payload) {...}.

Speaking of portability: C does have functions like these, but in the
portable version, the payload is a string and its interpretation is
supposed to be implementation-dependent, I suppose.

What guarantees will SRFI 208 make about `make-nan'?