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C++ proposal: There are exactly 8 bits in a byte

(www.open-std.org)
216 points Twirrim | 4 comments | 17 Oct 24 22:21 UTC | HN request time: 0.602s | source
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favorited ◴[17 Oct 24 23:54 UTC] No.41875023[source]▶
Previously, in JF's "Can we acknowledge that every real computer works this way?" series: "Signed Integers are Two’s Complement" <https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p09...>
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jsheard ◴[18 Oct 24 00:25 UTC] No.41875200[source]▶
Maybe specifying that floats are always IEEE floats should be next? Though that would obsolete this Linux kernel classic so maybe not.

https://github.com/torvalds/linux/blob/master/include/math-e...

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1. jcranmer ◴[18 Oct 24 04:54 UTC] No.41876461[source]▶
I'm literally giving a talk next week who's first slide is essentially "Why IEEE 754 is not a sufficient description of floating-point semantics" and I'm sitting here trying to figure out what needs to be thrown out of the talk to make it fit the time slot.

One of the most surprising things about floating-point is that very little is actually IEEE 754; most things are merely IEEE 754-ish, and there's a long tail of fiddly things that are different that make it only -ish.

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2. Terr_ ◴[18 Oct 24 05:03 UTC] No.41876497[source]▶
> there's a long tail of fiddly things that are different that make it only -ish.

Perhaps a way to fill some time would be gradually revealing parts of a convoluted Venn diagram or mind-map of the fiddling things. (That is, assuming there's any sane categorization.)

3. speedgoose ◴[18 Oct 24 05:06 UTC] No.41876510[source]▶
I'm interested by your future talk, do you plan to publish a video or a transcript?
4. chungy ◴[18 Oct 24 05:19 UTC] No.41876547[source]▶
The IEEE 754 standard has been updated several times, often by relaxing previous mandates in order to make various hardware implementations become compliant retroactively (eg, adding Intel's 80-bit floats as a standard floating point size).

It'll be interesting if the "-ish" bits are still "-ish" with the current standard.