› N5037 March 2026 admin telecon G. Davidson
Intent
Informational
Abstract
| Replaces: | | | 5035 | | --- | --- | --- | --- | | Date: | | | 2026-03-03 | | Reply to: | | | Guy Davidson (standard.guy@hatcat.com) |
› N5038 WG21 2026-03 Croydon Admin telecon minutes B. Ganetsky
Intent
Informational
Abstract
There will be about 6 meeting rooms in Croydon, 4 of which will be occupied all week long by the usual suspects. There is a “meeting rooms” wiki page. An email has been sent to ask that every subgroup chair requests meeting room space and time there. So far only 4 study groups have requested space and time. The rooms will be distributed based on those who registered. Anyone who is late will not ha
› N5040 WG21 2026-03 Croydon Hybrid Meeting Minutes B. Ganetsky
Intent
Informational
Abstract
Nina Ranns presents. Every participant is responsible for understanding and abiding by the following documents. It is assumed that every participant has read them before attending this meeting.
› N5043 Admin telecon 2026-05 G. Davidson
› P1000R8 Proposed C++ IS schedule G. Davidson
Intent
Proposal
Disposition Date
2026-03Adopted
› P2583R3 Info: Symmetric Transfer and Sender Composition M. Gill , V. Falco
Intent
Informational
Abstract
C++20 provides symmetric transfer ([P0913R1](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0913r1.html)[1]) - a mechanism where `await_suspend` returns a `coroutine_handle<>` and the compiler resumes the designated coroutine as a tail call. Coroutine chains execute in constant stack space. `std::execution`
› P3373R4 Of Operation States and Their Lifetimes R. Leahy
Intent
Proposal
Disposition Date
2026-03Adopted
Abstract
In broad terms a regular (i.e. synchronous) function call has access to two forms of storage throughout its lifetime (note that the “lifetime” of a regular function call is the time between the call thereto and the return therefrom):
› P4007R2 Info: Open Issues in `std::execution::task` V. Falco , M. Gill
Intent
Informational
Abstract
`std::execution::task` ([P3552R3](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2025/p3552r3.html)[1]) had open issues identified by national ballot comments, LWG issues, and published papers. Croydon resolved several. This paper classifies each issue by whether it can be resolved after C++26 ships or whether shipping forecloses the fix, and notes which classified issues were addressed at Cr
› P4014R1 Info: The Sender Sub-Language For Beginners V. Falco , M. Gill
Intent
Informational
Abstract
Every sender algorithm in C++26 - all thirty - explained, demonstrated, and mapped to its plain-C++ equivalent.
› P4028R0 2026-02 Library Evolution Poll Outcomes I. Levi , F. Fracassi , A. Weis , C. Jabot
Intent
Proposal
Abstract
In 2026-02, the C++ Library Evolution group conducted a series of electronic decision polls [[P4027R0]](https://wg21.link/P4027R0). This paper provides the results of those polls and summarizes the results.
› P4035R0 Info: The Need for Escape Hatches V. Falco
Intent
Informational
Abstract
C++ should make the safe thing easy, and the unsafe thing possible.
› P4043R0 Are C++ Contracts Ready to Ship in C++26? D. Neațu
Intent
Proposal
Abstract
The C++ Contracts facility introduced by P2900 represents a major addition to the C++ language, intended to support specification of program correctness through preconditions, postconditions, and assertions.
› P4088R0 Info: What C++20 Coroutines Already Buy The Standard V. Falco
Intent
Informational
Abstract
C++ already got an asynchronous model: regular C++20 coroutines.
› P4089R0 Info: On the Diversity of Coroutine Task Types V. Falco
Intent
Informational
Abstract
The Environment parameter in `std::execution::task` makes cross-library coroutine interoperability structurally impossible without knowing every query by name.
› P4090R0 Info: Sender I/O: A Constructed Comparison V. Falco
Intent
Informational
Abstract
The sender composition algebra does not apply to compound I/O results without losing data, and the construction that preserves all data produces code identical to the coroutine version.
› P4091R0 Info: Error Models of Regular C++ and the Sender Sub-Language V. Falco
Intent
Informational
Abstract
Both coroutines and senders destroy compound data at an abstraction floor - the difference is that the sender floor sits below the composition algebra, and the coroutine floor is opt-in.
› P4092R0 Info: Consuming Senders from Coroutine-Native Code V. Falco , S. Gerbino
Intent
Informational
Abstract
A single class template bridges sender-based code into coroutine-native I/O with inline operation state, correct stop propagation, and automatic dispatch-back.
› P4093R0 Info: Producing Senders from Coroutine-Native Code V. Falco , S. Gerbino
Intent
Informational
Abstract
Coroutine-native awaitables can be wrapped as senders, but compound I/O results must be reduced to an error code before crossing the bridge.
› P4094R0 Info: The Unification of Executors and P0443 V. Falco
Intent
Informational
Abstract
The unification of three working executor models had unanticipated downstream consequences.
› P4095R0 Info: The Basis Operation and P1525 V. Falco
Intent
Informational
Abstract
Of the four deficiencies that [P1525R0](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1525r0.pdf)[1] identified in `execute(F&&)`, three do not arise under the original framing of the callable as a continuation, and the fourth addresses a different question.
› P4096R0 Info: Coroutine Executors and P2464R0 V. Falco
Intent
Informational
Abstract
The committee set aside the Networking TS in 2021. The process had no mechanism to verify that the analysis examined every applicable framing, and no mechanism to revisit the outcome against evidence.
› P4097R0 Info: The Networking Claim and P2453R0 V. Falco
Intent
Informational
Abstract
The committee expressed consensus that sender/receiver is a good basis for networking. The published evidence behind that word is documented here.
› P4098R0 Info: Async Claims and Evidence V. Falco
Intent
Informational
Abstract
Published claims about executors, networking, and unification shaped a decade of committee decisions. The published evidence behind those claims is documented here.
› P4099R0 Info: The Twenty-One Year Networking Arc V. Falco
Intent
Informational
Abstract
Four decisions, each locally reasonable, each under-evidenced, produced a decade without networking in the C++ standard.
› P4100R0 Info: Coroutine-Native I/O for C++29 (The Network Endeavor) V. Falco , S. Gerbino , M. Vandeberg , M. Gill , M. Nejati
Intent
Informational
Abstract
C++ coroutines have five language mechanisms that combine into the ideal substrate for coroutine-native I/O.
› P4125R0 Info: Coroutine-Native I/O at a Derivatives Exchange M. Gill
Intent
Informational
Abstract
A derivatives exchange is porting from Asio callbacks to coroutine-native I/O. Early results: it works.
› P4126R0 Info: A Universal Continuation Model V. Falco , K. Morgenstern
Intent
Informational
Abstract
Senders pay a frame allocation to enter the awaitable protocol. They do not have to.
› P4137R0 Info: Profile Analysis and Verification Evidence (PAVE) V. Falco
Intent
Informational
Abstract
The paper offers a way to measure what the type-safety profile actually covers.
› P4145R0 C++ Standard Library Ready Issues to be moved in Croydon, Mar. 2026 J. Wakely
Intent
Proposal
Disposition Date
2026-03Adopted
› P4146R0 C++ Standard Library Immediate Issues to be moved in Croydon, Mar. 2026 J. Wakely
Intent
Proposal
Disposition Date
2026-03Adopted
› P4172R0 Info: IoAwaitable for Coroutine-Native Byte-Oriented I/O V. Falco , S. Gerbino
Intent
Informational
Abstract
This paper documents the design rationale for the *IoAwaitable* protocol.
› P4182R0 Info: A Citable Inventory of Platforms, Operating Systems, and Compiler Toolchains M. Gill
Intent
Informational
Abstract
Every mailing repeats the same deployment background. This paper puts one citeable inventory in the record.
