Dear all,

I wanted to share with you a quick summary of our recent C and C++ liaison meeting (that's SG22 in WG21), which happened last Friday. Some of this is known to some of you, but maybe it will come as news to others, and maybe we will want to consider some rapid reactions.

The meeting minutes are at https://wiki.edg.com/bin/view/Wg21telecons2021/Teleconference2021-09-10. Thanks a lot to Mark Hoemmen for scribing!

WG14 is getting ready to ship C23, and we saw two papers of liaison interest that they shared with us, one major and one minor. On our end, we shared one smaller, uncontroversial paper with them:

Floating point matters

Paper P2423R0 presents a summary of several new features that have already been adopted for C23 in the domain of floating points: this includes new types (some of them optional) for specific-width types as well as decimal floating point types, and a plethora of new library features (functions and macros). Members of SG6 Numerics were on the call and have been aware of this, but I wanted to raise awareness of these developments in a wider group: C will be adding significant amounts of material to <limits.h>, <float.h>, <math.h>, as well as to <complex.h> and <tgmath.h>. There will be many new types, and macros to detect whether certain types exist. I wanted to call out a few detailed concerns that we may want to consider:
I'm aware that David Olsen et al. have been doing a lot of work proposing new floating point types and type names for C++, and that there has already been a lively discussion on that. I just wanted to make sure everyone has a chance to see where C is going.

Best wishes,

Thomas
on behalf of SG22  -- C/C++ Liaison