<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body style="overflow-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;">CFP will discuss <div><br></div><a href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2023/p2746r0.pdf">https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2023/p2746r0.pdf</a><div><br></div><div>as a C++ liaison item at its January 8th meeting.</div><div><br></div><div>- Jim Thomas <br id="lineBreakAtBeginningOfMessage"><div><br><blockquote type="cite"><div>Begin forwarded message:</div><br class="Apple-interchange-newline"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px;"><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);"><b>From: </b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;">Hans Boehm <boehm@acm.org><br></span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px;"><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);"><b>Subject: </b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;"><b>Re: [isocpp-wg14/wg21-liaison] SG22 telco : P3477R0 and P2746R0</b><br></span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px;"><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);"><b>Date: </b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;">December 23, 2024 at 4:37:35 PM PST<br></span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px;"><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);"><b>To: </b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;">Nina Dinka Ranns <dinka.ranns@googlemail.com><br></span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px;"><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif; color:rgba(0, 0, 0, 1.0);"><b>Cc: </b></span><span style="font-family: -webkit-system-font, Helvetica Neue, Helvetica, sans-serif;">"boehm@acm.org" <boehm@acm.org>, Jim Thomas <jaswthomas@sbcglobal.net>, RAJAN BHAKTA <rbhakta@us.ibm.com><br></span></div><br><div><div>I'm fine with discussing either paper. I expect much less controversy<br>around p3475, which made it through 2 different WG21 committees, with<br>a total of 20 minutes of committee time. I would hope that a WG14<br>version would get a similar reception. I'm not aware of any C compiler<br>that implements memory_order_consume as intended either. It basically<br>removes a never-implemented feature.<br><br>Note that p2746 is not new to Jim or the CFP group, though the actual<br>library proposal has evolved a bit.<br><br>P2746 diverges from the WG14/C23 way of handling rounding modes. The<br>reasons for that are discussed in the paper. Basically:<br><br>1) Everyone involved in the discussion so far seemed convinced that<br>WG21 is very unlikely to accept the #pragma FENV_ROUND specification<br>in C23. So compatibility does not appear feasible.<br>2) IMO, there are significant technical arguments in favor of a<br>library-based, as opposed to scope-based approach. SG6 appears to<br>agree. My impression from WG14/CFP was that they would rather defer to<br>the more scope-based approach traditionally used by IEEE, mostly since<br>they view their charter more as connecting two standards than I think<br>SG6 does. Another major factor was presumably bad timing on my part,<br>in that the C23 work on #pragma FENV_ROUND had essentially been<br>completed by the time I presented P2746.<br>3) I'm concerned about what seems to me to be a disproportionately<br>large implementation effort to fully support FENV_ROUND in an area<br>that has relatively little client code that directly relies on it, and<br>has previously suffered from lack of implementer enthusiasm. That may<br>be improving; I'm not sure.<br><br>There was at some point vague discussion of a possible alternative<br>C23-like proposal to WG21/SG6, but that has not materialized. I'm not<br>sure what it would look like.<br><br>Hans<br><br>On Mon, Dec 23, 2024 at 6:44 AM Nina Dinka Ranns<br><dinka.ranns@googlemail.com> wrote:<br><blockquote type="cite"><br>Hi Hans,<br><br>I suggest we discuss https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2024/p3475r0.pdf on the 7th of January instead.<br>Thoughts ?<br><br>Thank you,<br>Nina<br><br>On Mon, 23 Dec 2024 at 14:38, Nina Dinka Ranns <dinka.ranns@googlemail.com> wrote:<br><blockquote type="cite"><br>Hi Rajan,<br><br>from my perspective, we can postpone for after the January 8th. SG22 can process other business instead.<br><br><br>Best,<br>Nina<br><br><br>On Mon, 23 Dec 2024 at 14:31, RAJAN BHAKTA <rbhakta@us.ibm.com> wrote:<br><blockquote type="cite"><br>Hi Nina,<br><br><br><br>If Jim and Hans agree, can we delay P2746R0 until WG14’s CFP study group meets to discuss this (on the 8th)?<br><br><br><br>Jim: Can we add this to the CFP agenda on January 8th as part of the C++ liaison section?<br><br>Hans: Can this wait one month?<br><br><br><br>Regards,<br><br>Rajan Bhakta<br><br><br><br><br><br>From: Liaison <liaison-bounces@lists.isocpp.org> on behalf of Nina Dinka Ranns via Liaison <liaison@lists.isocpp.org><br>Date: Monday, December 23, 2024 at 3:21 AM<br>To: WG14/WG21 liaison mailing list <liaison@lists.isocpp.org>, Hans Boehm <boehm@acm.org>, Robert Seacord <rcseacord@gmail.com>, Davis Herring <herring@lanl.gov>, JeanHeyd Meneide <wg14@soasis.org><br>Cc: Nina Dinka Ranns <dinka.ranns@googlemail.com><br>Subject: [EXTERNAL] [isocpp-wg14/wg21-liaison] SG22 telco : P3477R0 and P2746R0<br><br>Hi, Nina Dinka Ranns is inviting you to a scheduled Zoom meeting. Topic: SG22 Telco : P3477R0 and P2746R0 This is a meeting to discuss P3477R0 There are exactly 8 bits in a byte (JF Bastien) P2746R0 Deprecate and Replace Fenv Rounding Modes<br><br>Hi, Nina Dinka Ranns is inviting you to a scheduled Zoom meeting. Topic: SG22 Telco : P3477R0 and P2746R0<br><br><br><br>This is a meeting to discuss<br><br>P3477R0 There are exactly 8 bits in a byte (JF Bastien)<br><br>P2746R0 Deprecate and Replace Fenv Rounding Modes (Hans Boehm)<br><br><br><br>Time: Jan 7, 2025 07:00 PM Amsterdam, Berlin, Rome, Stockholm, Vienna (19:00 UTC)<br><br><br><br>Join from PC, Mac, Linux, iOS or Android: https://iso.zoom.us/j/96525564997?pwd=xaGbnpsdHNsqLOjZjJcLQHY7ebQ8Yb.1 Password: WG14WG21 Or iPhone one-tap : US: +14702509358,,96525564997# or +14703812552,,96525564997# Or Telephone: Dial(for higher quality, dial a number based on your current location): US: +1 470 250 9358 or +1 470 381 2552 or +1 602 753 0140 or +1 646 518 9805 or +1 646 876 9923 or +1 651 372 8299 or +1 669 219 2599 or +1 669 900 6833 or +1 720 928 9299 or +1 786 635 1003 or +1 971 247 1195 or +1 206 337 9723 or +1 213 338 8477 or +1 253 215 8782 or +1 267 831 0333 or +1 301 715 8592 or +1 312 626 6799 or +1 346 248 7799 or +1 408 638 0968 or 888 788 0099 (Toll Free) or 877 853 5247 (Toll Free) Meeting ID: 965 2556 4997 Password: 04636322 International numbers available: https://iso.zoom.us/u/ab4Rkf0Es1<br></blockquote></blockquote></blockquote></div></div></blockquote></div><br></div></body></html>