[Cfp-interest 2304] Re: CFP agenda update

[Damian McGuckin]

I was reminded earlier today that infinity is not a floating point number, 
as noted in 5.2.4.2.2 (which we were working on in the meeting). Is C ever 
likely to move to an IEEE 754 definition or stick with history. In IEEE754
(or IEC60559), infinite numbers are floating point numbers, at least as 
I read it.

 	floating-point datum: A floating-point number or non-number (NaN)
 	that is representable in a floating- point format. In this
 	standard, a floating-point datum is not always distinguished from
 	its representation or encoding.

 	floating-point number: A finite or infinite number that is
 	representable in a floating-point format. A floating-point datum
 	that is not a NaN. All floating-point numbers, including zeros and
 	infinities, are signed.

That said, within C23X, 5.2.4.2.2 says

.... An implementation that defines __STDC_IEC_60559_BFP__ or 
__STDC_IEC_559__ shall implement floating point types and arithmetic 
conforming to IEC 60559 as specified in Annex F.

So does that mean that in this case, infinity IS a floating point 
number.

I ask this because if this is the case, does not that mean that our 
document titled

 	5.2.4.2.2 cleanup (N2806	update)

i.e.

 	https://wiki.edg.com/pub/CFP/WebHome/C23_proposal_-_5.2.4.2.2_cleanup-update-20211221.pdf

needs to say something along the lines of

 	infinity is not (necessarily) a floating point number

Or am I getting my definitions badly confused?

Stay safe - Damian

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