WG21 PAPERS

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18 out of 18 papers selected for export
SelectPaper Title Authors Audience Doc Date
P1040R9 std::embed and #depend J. Meneide
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) JeanHeyd Meneide
Target Audience EWGLEWGCWG
Revisions R11R10
Tracking issue View on GitHub
Abstract > I’m very keen on std::embed. I’ve been hand-embedding data in executables for NEARLY FORTY YEARS now. — Guy "Hatcat" Davidson, June 15, 2018
P3596R1 Undefined Behavior and IFNDR Annexes J. Berne, T. Doumler, J. Maurer, S. Yaghmour
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Target Audience CWG
Revisions R3R2R0
Tracking issue View on GitHub
P3726R2 Adjustments to Union Lifetime Rules B. Revzin, T. Kamiński
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Target Audience CWGLWG
Tracking issue View on GitHub
Disposition Date 2026-03Adopted
Abstract [[P3074R7] (trivial `union`s (was `std::uninitialized<T>`))](https://wg21.link/p3074r7) was adopted in Hagenberg. One of the goals of that paper was to make an example like this work:
P3769R1 Clarification of placement new deallocation L. Vasama
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Lauri Vasama
Target Audience CWG
Tracking issue View on GitHub
Disposition Date 2026-03Adopted
Abstract [P3492R2] was forwarded to CWG in Hagenberg. In addition to its main language additions, it provided a drive-by fix for the poorly specified selection of deallocation functions in placement new expressions. The wording changes were split into this paper to make it easier to review the changes happening concurrently in this area:
P3795R2 Miscellaneous Reflection Cleanup B. Revzin
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Barry Revzin
Target Audience CWGLWG
Revisions R1
Tracking issue View on GitHub
Disposition Date 2026-03Adopted
Abstract At the Sofia meeting, [[P2996R13] (Reflection for C++26)](https://wg21.link/p2996r13), [[P3394R4] (Annotations for Reflection)](https://wg21.link/p3394r4), [[P3293R3] (Splicing a base class subobject)](https://wg21.link/p3293r3), [[P3491R3] (`define_static_{string,object,array}`)](https://wg21.link/p349143), [[P3096R12] (Function Parameter Reflection in Reflection for C++26)](https://wg21.link/p30
P3865R3 Class template argument deduction (CTAD) for type template template parameters C. Meerwald
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Christof Meerwald
Target Audience CWG
Revisions R2R1
Tracking issue View on GitHub
Disposition Date 2026-03Adopted
Abstract [CWG 3003](https://cplusplus.github.io/CWG/issues/3003.html) "Naming a deducible template for class template argument deduction" has been raised to clarify that with the current core language wording, class template argument deduction does not work for type template template parameters.
P3924R1 Fix inappropriate font choices for "declaration" J. Schultke
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Jan Schultke
Target Audience CWG
Tracking issue View on GitHub
Disposition Date 2026-03Adopted
P4004R1 Reconsider CWG 1395 "Partial ordering of variadic templates reconsidered" C. Meerwald
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Christof Meerwald
Target Audience CWG
Revisions R0
Tracking issue View on GitHub
Disposition Date 2026-03Adopted
Abstract ```cpp template<typename ... T> char *f(T &...); // #1 template<typename T> int *f(T &&); // #2 int i; auto *p = f(i); ```
P4101R0 Consteval-only Values for C++26 B. Revzin, P. Dimov, D. Vandevoorde, D. Katz
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Target Audience EWGCWG
Revisions R1
Tracking issue View on GitHub
Abstract The Reflection design from [[P2996R13]](https://wg21.link/p2996r13) was based on a model of having consteval-only types to prevent reflections from leaking to runtime. But we’ve run into issues and limitations with that approach, so we propose that, for C++26, we change instead to a consteval-only value model. This solves the same problems, but has additional benefits.
P4135R0 Consteval-only Types W. Childers
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Wyatt Childers
Target Audience EWGCWG
Tracking issue View on GitHub
Abstract If we take a step back and talk about types, a fundamental tenet is that types have invariants. These invariants are ultimately what drive many of the semantics of a C++ program. C++ would not be where it is today without RAII and RAII could not exist without a notion of invariants.
P4136R1 #line is not in line with existing practices C. Jabot
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Corentin Jabot
Target Audience CWG
Revisions R2R0
Tracking issue View on GitHub
Abstract line-directive: # line pp-tokens new-line The string-literal of a #line directive, if present, shall be a character string literal. The line number of the current source line is the line number of the current physical source line, i.e., it is one greater than the number of new-line characters read or introduced in translation phase 1[lex.phases] while processing the source file to the current prep
P4138R2 CWG3103 “Corresponding members and by-value object parameters” V. Serebrennikov
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Vlad Serebrennikov
Target Audience EWGCWG
Revisions R1R0
Tracking issue View on GitHub
Abstract While looking at [CWG3103](https://cplusplus.github.io/CWG/issues/3103.html), I got interested how we arrived at status quo, specifically how [[basic.scope.scope]/3.1](https://wg21.link/basic.scope.scope#3.1) came to be, and this is what I found. One of the conclusions I arrived at is that it doesn’t make much sense to overload member functions with explicit object parameter of non-reference type
P4143R0 Constant evaluation when? S. Herring
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) S. Davis Herring
Target Audience CWG
Tracking issue View on GitHub
Disposition Date 2026-03Adopted
Abstract This paper partially addresses US 33 (065) by clarifying what evaluations of a (putative) constant expression take place. It does not proceed further as would be necessary to support visible side effects during translation (*e.g.*, output as in [P2758](https://www.open-std.org/JTC1/SC22/WG21/docs/papers/2025/p2758r5.html)) because those do not exist in C++26.
P4149R1 Define "immediate context" A. Krzemieński, B. Bi
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Target Audience EWGCWG
Revisions R0
Tracking issue View on GitHub
Disposition Date 2026-03Adopted
P4160R0 Core Language Working Group "ready" Issues for the March, 2026 meeting J. Maurer
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Jens Maurer
Target Audience CWG
Tracking issue View on GitHub
Disposition Date 2026-03Adopted
P4175R0 Lift some arbitrary CTAD restrictions M. Izvekov
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Matheus Izvekov
Target Audience EWGCWG
Tracking issue View on GitHub
Abstract This paper proposes to relax some Class Template Argument deduction (CTAD) restrictions which were originally put in place for no well motivated reason other than simplicity and being conservative.
P4176R0 Grammar non-terminals for postfix-expressions V. Serebrennikov
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Vlad Serebrennikov
Target Audience CWG
Revisions R1
Tracking issue View on GitHub
Abstract 7.6.1 [[expr.post]](https://wg21.link/expr.post) lists all the grammar at the top, while the rest of the subclause resorts to either quoting the grammar or describing it with words. This paper aims to improve the situation, introducing new nonterminals and putting their definitions in the respective subclauses.
P4192R0 Better specification of alignment V. Serebrennikov
Intent Proposal
Mailing Date 2026-04 Post-Croydon
Author(s) Vlad Serebrennikov
Target Audience CWG
Tracking issue View on GitHub
Abstract There are multiple open Core issues against 6.8.3 [[basic.align]](https://wg21.link/basic.align) ([1211](https://cplusplus.github.io/CWG/issues/1211.html), [2840](https://cplusplus.github.io/CWG/issues/2840.html)) and 9.13.2 [[dcl.align]](https://wg21.link/dcl.align) ([1617](https://cplusplus.github.io/CWG/issues/1617.html), [2223](https://cplusplus.github.io/CWG/issues/2223.html), [3024](https://
Showing 18 of 18 papers · source: open-std.org