<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">David Olsen told me there is a newer version of the C++ paper to be discussed tomorrow:<div class=""><br class=""></div><div class=""> <a href="https://wg21.link/p1467r5" class="">https://wg21.link/p1467r5</a> or <a href="https://isocpp.org/files/papers/P1467R5.html" class="">https://isocpp.org/files/papers/P1467R5.html</a></div><div class=""><div class=""><br class=""></div><div class="">- Jim Thomas</div><div class=""><div><br class=""><blockquote type="cite" class=""><div class="">On Sep 26, 2021, at 9:57 AM, Jim Thomas <<a href="mailto:jaswthomas@sbcglobal.net" class="">jaswthomas@sbcglobal.net</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html; charset=us-ascii" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Aaron Ballman will be hosting the Zoom meeting for WG21 and CFP members to discuss issues with extension floating-point types. Information for joining the meeting is contained in the invitation (below) which Aaron sent to the C++ Numerics and WG14 reflectors.<div class=""><br class=""></div><div class="">- Jim Thomas</div><div class=""><br class=""></div><div class="">---<br class=""><br class="">Hello! I would like to invite everyone to attend an SG22-hosted<br class="">special discussion on Wed Oct 6 at 15:00 UTC<br class="">(<a href="https://www.timeanddate.com/worldclock/converter.html?iso=20211006T150000&p1=tz_pt&p2=tz_mt&p3=tz_ct&p4=tz_et&p5=1440&p6=tz_cest" class="">https://www.timeanddate.com/worldclock/converter.html?iso=20211006T150000&p1=tz_pt&p2=tz_mt&p3=tz_ct&p4=tz_et&p5=1440&p6=tz_cest</a>).<br class=""><br class="">P1467R4 (<a href="https://wg21.link/P1467R4" class="">https://wg21.link/P1467R4</a>) Extended floating-point types and<br class="">standard names<br class="">This will be a joint discussion with the C Floating Point Study Group.<br class="">The paper proposes allowing implementations to provide new extended<br class="">floating-point types in C++. C already allows such types through the<br class="">integration of TS18661 into C23. The authors would like to have a<br class="">discussion around the names of the types and the header where the<br class="">names are defined, and a discussion of where the behavior of these<br class="">types differ between languages, including implicit conversions and<br class="">usual arithmetic conversions. We expect to take preference polls on<br class="">naming decisions.<br class=""><br class="">Topic: Joint Discussion of P1467R4<br class="">Time: Oct 6, 2021 11:00 AM Eastern Time (US and Canada)<br class=""><br class="">Join from PC, Mac, Linux, iOS or Android:<br class=""><a href="https://iso.zoom.us/j/5513145100?pwd=SnhxSmJiV2tsemtxbS9HSTl0cUtLZz09" class="">https://iso.zoom.us/j/5513145100?pwd=SnhxSmJiV2tsemtxbS9HSTl0cUtLZz09</a><br class=""> Password: please contact Aaron Ballman or Jim Thomas for the password<br class=""><br class="">Or iPhone one-tap :<br class=""> US: +16027530140,,5513145100# or +12532158782,,5513145100#<br class="">Or Telephone:<br class=""> Dial(for higher quality, dial a number based on your current location):<br class=""> US: +1 602 753 0140 or +1 253 215 8782 or +1 346 248 7799<br class="">or +1 408 638 0968 or +1 669 219 2599 or +1 669 900 6833 or +1 720<br class="">928 9299 or +1 971 247 1195 or +1 206 337 9723 or +1 213 338 8477<br class="">or +1 312 626 6799 or +1 470 250 9358 or +1 470 381 2552 or +1 646<br class="">518 9805 or +1 646 876 9923 or +1 651 372 8299 or +1 786 635 1003<br class="">or +1 267 831 0333 or +1 301 715 8592 or 877 853 5247 (Toll Free) or<br class="">888 788 0099 (Toll Free)<br class=""> Meeting ID: 551 314 5100<br class=""> Password: 89239314<br class=""> International numbers available: <a href="https://iso.zoom.us/u/aQsAgOF5z" class="">https://iso.zoom.us/u/aQsAgOF5z</a><br class=""><br class="">Or Skype for Business (Lync):<br class=""> <a href="https://iso.zoom.us/skype/5513145100" class="">https://iso.zoom.us/skype/5513145100</a></div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""><div class=""><br class=""><blockquote type="cite" class=""><div class="">On Sep 22, 2021, at 11:49 AM, Jim Thomas <<a href="mailto:jaswthomas@sbcglobal.net" class="">jaswthomas@sbcglobal.net</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;">It looks like the best time for the meeting, for attendance from WG21 and CFP, will be Wednesday, October 6, at 8 AM PDT / 11 AM EDT / 3 PM UTC.<div class=""><br class=""></div><div class="">- Jim Thomas<br class=""><div class=""><br class=""><blockquote type="cite" class=""><div class="">On Sep 21, 2021, at 2:01 PM, Jim Thomas <<a href="mailto:jaswthomas@sbcglobal.net" class="">jaswthomas@sbcglobal.net</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;">Please also let me know if you could attend on Tuesday, October 5, same time.<div class=""><br class=""></div><div class="">- Jim Thomas<br class=""><div class=""><br class=""><blockquote type="cite" class=""><div class="">On Sep 20, 2021, at 5:45 PM, Jim Thomas <<a href="mailto:jaswthomas@sbcglobal.net" class="">jaswthomas@sbcglobal.net</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;"><div class="">The C/C++ liaison group has been discussing at some length possible conflicts (see below) with the WG21 proposal for extension floating-point types and the new C23 annex for TS-3. Aaron Ballman, as SC22 chair, suggested a joint 1-hour meeting with CFP and interested WG21 members as a forum to deal with the concerns. After email discussion, Aaron, Rajan, and I decided to propose <b class="">Wednesday, October 6, at 8 AM PDT / 11 AM EDT / 3 PM UTC. Would you be able to attend a zoom meeting at that time? Please respond if possible by end of Tuesday, September 21.</b></div><div class=""><br class=""></div><div class="">- Jim Thomas<br class=""><div class=""><br class=""></div><div class="">Aaron wrote:</div><div class=""><br class=""></div><div class=""><blockquote type="cite" class="">Here's the summary of topics I've pulled together from the various<br class="">reflector discussions:<br class=""><br class="">* Currently, the new types are exclusively available in the<br class="">_Reserved_name spelling (like "_Bool" was in C99), there is no set of<br class="">"pretty" macros (like "bool" was in <stdbool.h>) -- that means that if<br class="">C++ decides to introduce new pretty names like (std::)float16_t, we<br class="">have no immediately interoperable name (like "float16_t") that would<br class="">be valid C, since there is no macro "#define float16_t _Float_16",<br class="">say.<br class=""><br class="">* The proposed rules for C and C++ have different arithmetic conversion rules:<br class=""> float + _Float32 -> _Float32<br class=""> float + std::float32 -> float<br class=""><br class="">* The above point is observable in that you get UB when passing a<br class="">_Float32 vs a float as a vararg parameter due to the promotion rules<br class="">(float promotes to double, _Float32 does not).<br class=""></blockquote><br class=""><blockquote type="cite" class="">It's possible I've missed some points (there are a few threads going<br class="">with a lot of messages on each of them), but Fred Tydeman and Joseph<br class="">Myers have both weighed in on the thread, which is helpful! ...</blockquote></div></div></div></div></blockquote></div><br class=""></div></div></div></blockquote></div><br class=""></div></div></div></blockquote></div></div><div class=""><br class=""><blockquote type="cite" class=""><div class="">On Sep 22, 2021, at 11:49 AM, Jim Thomas <<a href="mailto:jaswthomas@sbcglobal.net" class="">jaswthomas@sbcglobal.net</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html; charset=us-ascii" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">It looks like the best time for the meeting, for attendance from WG21 and CFP, will be Wednesday, October 6, at 8 AM PDT / 11 AM EDT / 3 PM UTC.<div class=""><br class=""></div><div class="">- Jim Thomas<br class=""><div class=""><br class=""><blockquote type="cite" class=""><div class="">On Sep 21, 2021, at 2:01 PM, Jim Thomas <<a href="mailto:jaswthomas@sbcglobal.net" class="">jaswthomas@sbcglobal.net</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html; charset=us-ascii" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Please also let me know if you could attend on Tuesday, October 5, same time.<div class=""><br class=""></div><div class="">- Jim Thomas<br class=""><div class=""><br class=""><blockquote type="cite" class=""><div class="">On Sep 20, 2021, at 5:45 PM, Jim Thomas <<a href="mailto:jaswthomas@sbcglobal.net" class="">jaswthomas@sbcglobal.net</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html; charset=us-ascii" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class="">The C/C++ liaison group has been discussing at some length possible conflicts (see below) with the WG21 proposal for extension floating-point types and the new C23 annex for TS-3. Aaron Ballman, as SC22 chair, suggested a joint 1-hour meeting with CFP and interested WG21 members as a forum to deal with the concerns. After email discussion, Aaron, Rajan, and I decided to propose <b class="">Wednesday, October 6, at 8 AM PDT / 11 AM EDT / 3 PM UTC. Would you be able to attend a zoom meeting at that time? Please respond if possible by end of Tuesday, September 21.</b></div><div class=""><br class=""></div><div class="">- Jim Thomas<br class=""><div class=""><br class=""></div><div class="">Aaron wrote:</div><div class=""><br class=""></div><div class=""><blockquote type="cite" class="">Here's the summary of topics I've pulled together from the various<br class="">reflector discussions:<br class=""><br class="">* Currently, the new types are exclusively available in the<br class="">_Reserved_name spelling (like "_Bool" was in C99), there is no set of<br class="">"pretty" macros (like "bool" was in <stdbool.h>) -- that means that if<br class="">C++ decides to introduce new pretty names like (std::)float16_t, we<br class="">have no immediately interoperable name (like "float16_t") that would<br class="">be valid C, since there is no macro "#define float16_t _Float_16",<br class="">say.<br class=""><br class="">* The proposed rules for C and C++ have different arithmetic conversion rules:<br class=""> float + _Float32 -> _Float32<br class=""> float + std::float32 -> float<br class=""><br class="">* The above point is observable in that you get UB when passing a<br class="">_Float32 vs a float as a vararg parameter due to the promotion rules<br class="">(float promotes to double, _Float32 does not).<br class=""></blockquote><br class=""><blockquote type="cite" class="">It's possible I've missed some points (there are a few threads going<br class="">with a lot of messages on each of them), but Fred Tydeman and Joseph<br class="">Myers have both weighed in on the thread, which is helpful! ...</blockquote></div></div></div></div></blockquote></div><br class=""></div></div></div></blockquote></div><br class=""></div></div></div></blockquote></div><br class=""></div></div></blockquote></div><br class=""></div></div></body></html>