Trip report: June 2026 ISO C++ standards meeting (Brno, Czechia)

tl;dr… A few highlights Adopted this week in draft C++29: Complete catalog of all undefined behavior (UB) in C++. Contract pre/post support for virtual functions. Defaulting (=default) for postfix increment/decrement. Designated initializers for base classes. Python-style .lookup(key) for associative containers. And more… Other significant progress: Progress on various features targeting C++29, including systematically addressing UB and adding safety profiles for C++. Next six months: Telecon line-by-line review of a proposal to systematically address all undefined behavior in C++. Progress adding C++ memory safety subsetting profiles. Both aim for inclusion in C++29. Overview A few minutes ago, the ISO C++ committee completed the first meeting of C++29 in beautiful Brno, Czechia (hybrid online via Zoom). This meeting was hosted by Mendel University in Brno. Thank you to everyone involved, including especially Hana Dusíková who took the lead in making the arrangements! Our hosts…