Document: N5035 Author: Guy Davidson Date: 2026-01-27 Audience: All of WG21 Completing the 2026-02 mailing. Yes, all of it. This one is Guy Davidson's agenda document for the March 2026 WG21 admin telecon — scheduling, logistics, liaison reports, the coordination layer that...
Document: N5036 Author: Michael Wong, SG5 Date: 2026-02-22 Audience: All of WG21 White paper from SG5 on transactional memory extensions for C++, version 2. If you care about TM in the language, this is the committee-facing framing document — not a wording paper, but the problem...
Document: N5037 Author: Guy Davidson Date: 2026-03-03 Audience: All of WG21 This is the replacement filing for the March 2026 WG21 admin telecon agenda—same document family as the earlier version, now with updated logistics. Primary source: N5037 (PDF). The mailing index marked...
Document: P0876R22 Author: Oliver Kowalke, Nat Goodspeed Date: 2026-02-23 Audience: LEWG Library Evolution, CWG Core, LWG Library Fresh revision in the 2026-02 mailing. This paper keeps pushing as a low-level fiber primitive with an explicit resume/suspend surface and no...
Document: P2000R5 Author: Michael Wong, J. Garland, P. McKenney, R. Orr, B. Stroustrup, D. Vandevoorde, M. Wong Date: 2026-02-23 Audience: All of WG21 My fetch script coughed up until I stopped pretending curl with no credentials was a personality. Grabbed the PDF from open-std...
Document: P2285R1 — Are default function arguments in the immediate context? Author: Andrzej Krzemiński, Tomasz Kamiński Date: 2026-02-23 Audience: EWG Evolution This paper is about whether substitution failures in default function arguments (and related defaults) belong in the...
Document: P2583R0 Author: Mungo Gill, Vinnie Falco Date: 2026-02-22 Audience: LEWG This paper argues that C++20 symmetric transfer and the P2300 sender model are structurally awkward together when you coawait sender algorithms: receivers use void-returning hooks, so awaitsuspend...
Document: P2728R11 Author: Eddie Nolan Date: 2026-02-23 Audience: SG9 Ranges, SG16 Unicode, LEWG Library Evolution This revision keeps pushing UTF transcoding as range adaptors ( , , , plus shapes) so you can lazily transcode without deprecated . If some tool answers with HTTP...
Document: P2929R2 Author: Daniel Towner, Ruslan Arutyunyan Date: 2026-02-20 Audience: LEWG Library Evolution R2 keeps pushing for : you get a callable applied over chunks with a max chunk size so mixed-width SIMD patterns (classic add/sub interleave stuff) are less bespoke than...
Document: P2953R4 Author: Matthew Taylor, Arthur O'Dwyer Date: 2026-02-22 Audience: EWGI SG17: EWG Incubator P2953R4 argues against defaulting in cases the authors treat as a value-semantics and foot-gun. If you maintain types with explicit object parameters or care what a...
Document: P2964R2 Authors: Daniel Towner, Ruslan Arutyunyan Date: 2026-02-19 Audience: SG6 Numerics, LEWG Library Evolution This revision keeps pushing on a practical pain point: you have , but the element type story has been narrow. The paper spells out when a user-defined type...
Document: P3045R7 Author: Mateusz Pusz, Dominik Berner, Johel Ernesto Guerrero Peña, Chip Hogg, Nicolas Holthaus, Roth Michaels, Vincent Reverdy Date: 2026-02 Audience: SG6, SG16, LEWGI Canonical copy: wg21.link/p3045r7. This paper proposes a type-safe quantities and units...
Document: P3181R1 Author: Hans Boehm, Dave Clausen, David Goldblatt Date: 2026-02 Audience: SG1 (Concurrency) This revision argues the lifetime rules are overly conservative when the final update is a relaxed atomic store after a release fence, and proposes wording so...
Document: P3385R7 Author: Aurelien Cassagnes Date: 2026-02-16 Audience: EWG, LEWG This revision builds on the P2996 reflection framework and aims at attributes: reflecting standard (and some vendor) attribute syntax, comparing reflections, and wiring that into metaprogramming so...
P3411R5 — any_view
WG21
Document: P3411R5 — anyview Author: Hui Xie, Louis Dionne, S. Levent Yilmaz, Patrick Roberts Date: 2026-02 (WG21 mailing) Audience: SG9, LEWG If your HTTP client calls P3411R5 without an header and gets , that is a client configuration issue, not something the paper can...
Document: P3440R2, revision 2 Author: Daniel Towner Date: 2026-02-20 Audience: LEWG (Library Evolution) Small LEWG paper: it adds a named constructor so you can spell how many elements you want in the type, instead of leaning on width-only or implementation-defined shortcuts...
Document: P3596R0 — Undefined Behavior and IFNDR Annexes Author: Joshua Berne, Timur Doumler, Jens Maurer, Shafik Yaghmour Date: February 2026 Audience: CWG This paper proposes two informative annexes that catalog core undefined behavior and IFNDR cases with stable identifiers...
Document: P3642R4 Author: Jan Schultke Date: 2026-02-17 Audience: LEWG (Library Evolution) P3642R4 proposes carry-less multiplication in : , a widening returning low/high parts, and overloads where they fit. The motivation is the usual suspects (CRC-like work, crypto-adjacent...
Document: P3666R3 Author: Jan Schultke Date: 2026-02-21 Audience: EWG, LEWG R3 pulls C23 into C++ as first-class types: / literals, / aliases, and library surface area ( , , traits, , and friends). The design leans hard on matching C23's rank, promotion, and conversion rules so...
Document: P3688R6 Author: Jan Schultke, Corentin Jabot Date: 2026-02-21 Audience: SG16 (Unicode) Revision 6 still aims at a dedicated header with constexpr, locale-independent ASCII tests and transforms across char, wchart, char8t, char16t, and char32t—basically fixing the /...
Document: P3724R3 Author: Jan Schultke Date: 2026-02-20 Audience: LEWG Library Evolution This paper adds a small but sharp toolbox around integer division: named rounding modes (toward negative infinity, positive infinity, away from zero, ties-to-even, and friends), paired...
Document: P3737R3 Author: Jan Schultke Date: 2026-02 Audience: LEWG (Library Evolution) This revision tries to nail down what everybody already assumes: is literally a thin wrapper around a member (or the zero-size trick), so layout and triviality line up with a C array. It also...
Document: P3816R2 Authors: Matt Cummins, Valentyn Yukhymenko Date: 2026-02-23 Audience: SG7 Reflection This paper proposes with a specialization for so you can key compile-time maps off reflection handles without reinventing ad hoc mixing. The hash is semi-stable within a...
Document: P3822R1 Author: Viacheslav Luchkin, Gašper Ažeman Date: 2026-02-23 Audience: EWG Evolution R1 extends compound requirements in -expressions so you can write instead of cloning whole clauses when checking should depend on a template parameter—basically the same...
Document: P3844R3 — Restore simd::vec broadcast from int Author: Matthias Kretz Date: 2026-02-06 Audience: LWG Library This revision targets a small but painful simd ergonomics hole: getting a sensible broadcast when you hand a scalar int to code that wants a std::simd vector...
Document: P3844R4 Author: Matthias Kretz Date: 2026-02-13 Audience: LWG Matthias Kretz is back with another C++26 wording cleanup — this one fixing a genuine footgun lurking in . The issue: the old macro pattern uses to compute a common SIMD type across mixed scalar/SIMD...
Document: P3856R4 Author: Jagrut Dave, Alisdair Meredith (Bloomberg) Date: 2026-01-17 Audience: LEWG / LWG You know that pattern where you want to constrain V to types that can legally appear as non-type template parameters? There is a specific property called a structural type...
Document: P3856R5 Author: Jagrut Dave, Alisdair Meredith (Bloomberg) Date: 2026-02-10 Audience: LEWG / LWG --- You know how C++20 expanded NTTPs to allow class types as template parameters? The standard defines exactly what a "structural type" means — scalar, lvalue reference...
Document: P3864R1 Authors: Guy Davidson, Jan Schultke Date: 2026-02-22 Audience: SG6 (Numerics), SG22 (Compatibility) Five new standard library functions — , , , , — that guarantee IEEE 754 roundTiesToEven regardless of the current floating-point environment. They live in , are...
Document: P3874R1 Authors: Jon Bauman, Timur Doumler, Nevin Liber, Ryan McDougall, Pablo Halpern, Jeff Garland, Jonathan Müller Date: February 2026 Audience: EWG This is the paper that asks the uncomfortable question out loud: should C++ formally commit to becoming a memory-safe...
Document: P3876R1 Authors: Jan Schultke, Peter Bindels Date: 2026-02-22 Audience: SG16 (Unicode and text) and have existed since C++17, and they are genuinely great — fast, locale-independent, no allocation, no exceptions. There is exactly one problem: they only accept . Want to...
Document: P3899R1 Authors: Jan Schultke, Matthias Kretz Date: 2026-02-20 Audience: SG6 (Numerics), EWG (Evolution), CWG (Core Wording) For roughly a decade, the C++ standard has been technically ambiguous about whether is undefined behavior on a platform with IEEE 754 infinity...
Document: P3904R1 Author: Victor Zverovich Date: 2026-01-28 Audience: SG16 So P2845 landed in C++26 and fixed most of the formatting mess — you can now print a path containing Cyrillic or CJK characters on Windows without getting garbage, which was genuinely broken before...
Document: P3932R0 — Fix LWG4470: Fix integer-from in [simd] Author: Matthias Kretz Date: 2026-02-13 Audience: LWG (C++26) Three LWG issues in one pass. The headline is LWG4470: was used throughout to derive a signed integer type from an element byte count — works great until is...
Document: P3936R1 — Safer atomicref::address (FR-030-310) Author: Corentin Jabot, Gonzalo Brito Gadeschi (NVIDIA) Date: 2026-01-27 Audience: LWG (Library Working Group) currently returns . That pointer lets you read and write the underlying object directly, bypassing the atomic...
Document: P3938R1 Author: Jan Schultke Date: 2026-02-20 Audience: SG6 (Numerics), EWG, CWG It is 2026 and the C++ standard still does not formally specify what values a floating-point type may represent. Can a hold infinity from the core language’s perspective? Is negative zero...
Scheduler Affinity
WG21
Document: P3941R2 Author: Dietmar Kühl (Bloomberg) Date: 2026-02-23 Audience: SG1, LEWG, LWG If you've been using coroutines — specifically — and wondering how actually guarantees a coroutine resumes on the correct scheduler after every , this paper is the answer. Or rather...