Issaquah Trip Report, days four to six

general remarks about the meetings

First, a caveat emptor:  the Hilton Garden Inn in Issaquah, Washington lacks a proper restaurant.  Instead, they have a bar that has limited menus for breakfast and supper…no lunch at all.  Also, they don’t send out laundry or dry cleaning, so I’ll be a mess on my trip home (not dirty or smelly, but definitely unpressed).

2023-02-06:
The plenary session where we took care of administrivia only lasted until the morning break.

For the rest of the day, I hung out in the Library Evolution Working Group (LEWG) where we dealt with eleven papers.  Four answered national body comments, one fixed a bug (for which there was no NB comment), and one answered a comment from the Core (language) Working Group (CWG).  That completed our high priority business, so the other five papers were suggestions for new standard library features.  We’ll be talking mostly about new features for the rest of the week since that’s what LEWG is about anyway.

2023-02-07:
This old dude was happy to catch up on his sleep and write the blog post I linked to above.  I’m pretty sure that nobody on the committee missed me. 😎

The hotel doesn’t have all the meeting rooms that we need, so some groups have evening sessions.  I attended an evening session of the Numerics Study Group where we considered three papers, one suggesting additional statistics functions, one about an extension to the random number business, and one claiming that more math functions could be declared constexpr (“constant expression”).  There was a fourth paper that dealt with deprecating and replacing the fsetround and fgetround functions in the floating point environment that C++ inherits from C.  We got through the rationale for deprecating the functions, but we ran out of time before we could talk about what to replace them with.  We’ll have another evening session on Thursday when, if we have the time, we might also talk about my paper.  (The floating point stuff is very much more important.)

2023-02-08:
LEWG spent the whole day talking about SIMD stuff (“single instruction, multiple data”).

<aside>
The committee can publish three kinds of documents, an international standard (IS), a technical specification (TS) which is a kind of warning about possible future standardization (“Hey, vendors and users, try this out and let us know if we made any mistakes.”), and a technical report (TR) which is basically “Here’s something we thought you might find interesting.”
</aside>

We have a TS that defines a class called simd that provides a mechanism for doing parallel processing of vectorizable data on multicore machines, which is a Really Big Deal for the numerics folks.  As expected, “mistakes were made;” and fixing them has lots of subtle ramifications.  This took lots of discussion among numerics experts, most of which went over my head.  (One of the reasons that I participate in the committee is that I can learn lots of stuff just by keeping my mouth shut and my ears open.  I hope I never stop learning.)

Issaquah Trip Report, the reason for the trip

Here begins the part of my trip report that talks about the reason for the trip.  I’ll probably combine several days into single posts since I might not have much to say that would be of interest to a general audience.

This week I’m attending meetings of ISO/IEC JTC1 SC22 WG21 and INCITS/C++, the standards committees for the C++ programming language.  (It’s not a joint meeting, but the two committees meet at the same place at the same time.  Ask the lawyers, I don’t understand it.)

I’ll begin by briefly describing how these meetings work, and then “below the fold” I’ll have a bunch of geeky info for folks who really like organizational charts (although I won’t have any actual charts).

We meet in full committee three times per year, although it was pretty much all Zoom during COVID.  The first post-COVID face-to-face meeting was in November in Kailua-Kona, Hawaii (which I missed).  This week we’re meeting in Issaquah, Washington, a suburb of Seattle.  The summer meeting will be in June in Varna, Bulgaria.

We meet for five and a half days.  Monday morning is a plenary session where we handle a bunch of administrivia (approve the agenda, approve the previous meeting’s minutes, stuff like that).  After lunch, we break into subgroups where most of the actual work gets done.  Saturday morning is another plenary session where we take formal votes.  By the time we get to Saturday, everything is pretty much a done deal; and with the odd exception here and there, all motions pass by unanimous consent.

A couple hundred people from around the world show up at the meetings, and we’d never get anything done if we tried to do the real work in plenary sessions.  Also, nobody knows everything, so we tend to gravitate to smaller groups where we might have some useful input.  I, for example, will probably participate mostly in the Library Evolution Working Group which considers changes to the standard library.

We’ve adopted a very aggressive schedule of publishing a new version of the C++ standard every three years; and since C++11, we’ve published C++14, C++17 and C++20.  Our main focus this week will be answering national body comments that were part of the result of the C++23 final committee draft (FCD) ballot.  We hope to instruct the WG21 convenor (the person in charge, kind of like a chair) to send the draft international standard (DIS) out for ballot on Saturday.  We’ll know the results of that ballot in a few months, at which time we might have more national body comments to answer, or the document might go straight to being published as an international standard (IS).  We’ll see…

OK, now for the boring organizational stuff:

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