Birds of a Feather

Welcome to C++ 23, the “Pandemic” Edition and C++ NEXT in 2026

Authors: Michael Wong (Codeplay Software Ltd, UK; Khronos Group Inc), Hal Finkel (DOE Office of Advanced Scientific Computing Research)

Abstract: Welcome to C++ 23, the “pandemic” edition. C++ was named Tiobe Programming Language of the Year for 2022 by the Tiobe Index of language popularity. C/C++ is used in 79.4% of parallel programming languages based on Hyperion 2021 research HPC Briefing at ISC 2021. We will review C++23 final content and implementation status by all compilers while we look ahead to see what is coming for C++ 26. This BoF will pull together important leader within ISO C++ Standard that are co-authors in key C++23 features such as ML, executors, mdspan, library and Concurrency.

Long Description: Welcome to C++ 23, the “pandemic” edition. After 3 years of working through the pandemic, ISO C++ has completed C++23. We are now working on C++26 and the 2 recent meetings have already added a large number of features for C++26. In fact, we will be fresh from the Kona F2F meeting the week before.

THE C++23 content include to name a few: Standard library with module support Simplified implicit move Multidimensional and static operator [] Unicode improvements Static constexpr in constexpr functions The equality operator you are looking for

In the meantime, C++26 already will have SIMD which used to be Parallelism TS2. Another important item entered in C++26 are 2 lock-free algorithms on Hazard Pointers and RCU.

All these points to more need for C++ parallelism, and ultimately support for acceleration. Some of this is shown in the upcoming Concurrency TS2 which contains more lock-free libraries.

C++ was named Tiobe Programming Language of the Year for 2022 by the Tiobe Index of language popularity. But it is an interesting time for C++ as there has never been more news about possible beyond C++ contenders, such as Carbon, Circle, Val, cpp2/cppfront, even Rust. Recently, a critique of the memory safety of C/C++ by the NSA has at least in some small way motivated the start of a movement to improve Safety Security in C++ after drawing sharp rebuttal from Bjarne Stroustrup. We will discuss all these future directions. We think C++ will survive all this and come out even stronger, but it is a great time to participate in the debate.

After the last six years’ (SC17, SC18, SC19, SC20, SC21, SC22) successful C++ for HPC BoF, there was popular demand for continuing updates on the progress of adding HPC capabilities into ISO C++. This is especially important with the increasing use of C++ within DOE.

This BoF will pull together important leader within ISO C++ Standard that are co-authors in key C++23 features such as ML, executors, mdspan, library and Concurrency while continuing to poll for audience participation and response, answering key design questions based on the open community question banks that were collected from the audience last year but were not answered due to lack of time.

This feedback will help us design the best capabilities into future ISO C++ suitable for HPC, building on the many current languages/libraries that pre-date and support this effort that have implemented heterogeneous and distributed C++ features (e.g. Kokkos, Raja, SYCL, HiP, HPX, C++AMP, HCC, Boost.Compute and CUDA). This BoF will address the needs of the HPC community where a number of C++ frameworks have been developed for multi-threaded and distributed applications. The C++11/14/17/20/23 international standards have introduced new tools for parallel programming, concurrency (Concurrency TS2).

This BoF is targeted to developers of C++ based programming models, users and designers of distributed and heterogeneous programming models for C/C++, ISO standard members, DOE and worldwide research lab members (e.g. CERN, BSC, CSSC) with workloads in C++ looking for a native language solution.

Website: https://isocpp.org