September 17th 2025: twelfth Kokkos tea-time

Experience converting large scientific software packages written in C++ to C++20 modules

May 19, 2025

CExA organizes its twelfth international Kokkos tea-time on Wednesday, September the 17th, 2025 for 45min starting at 7AM PDT, 9AM MDT, 11AM EST, 3PM UTC, 4PM CEST. It can be followed on Zoom, by phone, or from a visio room.

Wolfgang Bangerth will give a talk entitled “Experience converting large scientific software packages written in C++ to C++20 modules”

Wolfgang Bangerth
Wolfgang Bangerth

Wolfgang Bangerth is a professor of mathematics and geosciences at Colorado State University, USA. He holds an undergraduate degree in physics, and a PhD in mathematics from Heidelberg University, Germany. As a graduate student in 1997, he co-founded the deal.II project (https://www.dealii.org), a widely used software library that provides finite element functionality. He is now one of the Principal Developers of the project.

Experience converting large scientific software packages written in C++ to C++20 modules

Many of the most widely used scientific software libraries are written in C++, but almost all of them still use the traditional header-based approach inherited from C to connect declarations provided in one file to uses and implementations in another file. On the other hand, C++20 has introduced a module system that is intended to give C++ a proper “import” statement that goes beyond the textual inclusion of “#include”.

In this talk, I will outline my experience with converting the deal.II finite element library – a library with 1.8M lines of C++ – to use C++20-style modules. I will discuss how I did this from a technical perspective, and in particular how that actually works in practice.

Contribute

Any subject is welcome if it is related to the Kokkos ecosystem (developments, usage, projects, issues, etc.) or even to GPU programming at large. Feel free to contact us to propose a talk: contact@cexa-project.org

We target very informal discussion in English. You can propose any subject for discussion even if you don’t have a dedicated slide deck.

Additional info

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Dr. Julien Bigot
Dr. Julien Bigot
PI