P0554 mentions an run-time-only overflow handler, `overflow_integer` (similar to P0228's type) and a compile-time overflow avoider, `elastic_integer`. They ought to find their way into a numeric TS, the beginnings of which -- fingers-crossed -- will be in the post-Cologne mailing.

Christopher: the unique_function paper is a typo, that's actually P0288. Use https://wg21.link/p0228r0 to get Robert's paper.

On Sat, 3 Aug 2019 at 05:49, Federico Kircheis via Std-Discussion <std-discussion@lists.isocpp.org> wrote:
On 02.08.19 20:11, David Svoboda via Std-Discussion wrote:
> Hello, I am curious as to the status of the document P0228R0 in C++?
>    http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0228r0.pdf
> It was written in Feb 2016, but I can't seem to access any WG21 meeting
> minutes newer than that.
> More to the point, I am wondering if there are any proposals for safe
> integer operations, and if so, what is their status? Did they get
> adopted into a TS? They didn't seem to make it into C++17 or 20.

I've chatted with Robert Ramey a couple of years ago about it, this is
what he wrote me (in case he is not in the mailing list):

I made a presentation to the SG-6 committee via skype in February 2016.
The response was not negative, but not enthusiastic either.  I concluded
that getting something like safe numerics into the standard would be a
lot of work, require attendance at many meetings, be extremely tedious
and take several years.  I've also concluded that for very complex
libraries such as this one, the standards track doesn't work well. I
concluded that it wasn't worth it.  When I was recently contacted by the
committee about the proposal we discussed the above and they decided to
put the proposal on "hold" which was fine by me.

I redirected my efforts to getting safe numerics accepted as a boost
library.  It got 5 reviews - all positive - and so was accepted -
subject to a long list of conditions.  This list was basically what was
needed to "finish" the library: fix bugs, refine concepts, add more
tests, etc. etc.  I've been working on this since the review - it's a
lot of work.  I thought the library was in very good shape. The review
made it clear that I was wrong about this.  On the good side, the
changes are working out well and I'm optimistic that the library will be
of high quality when merged into boost.  I'm hoping this will occur
before CPPCon in september.

Then the real work begins.  Most programmers do not believe that
erroneous arithmetic results are a serious problem and that addressing
them is not worth the hit on performance.  I'm convinced otherwise of
course so I will have to spend time evangelizing the usage of the safe
numerics library.

So, unless something has changed (discussion was in 2017) there is no
further work, and that's why you could only find the minutes from Feb 2016.

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