Taming the UB Monsters in C++

For more background on safety and security issues related to C++, including definitions of “language safety” and “software security” and similar terms, see my March 2024 essay “C++ safety, in context.” This essay picks up our story where that one left off to bring us up to date with a specific focus on undefined behavior (aka UB). This is a status update on improvements currently in progress for hardening and securing our C++ software. The C++ community broadly has a lot of hardening work well underway. Across the industry, this includes work being done by individual vendors, that they are then contributing to the standardization process so C++ programmers can use it portably. In the standard, it includes things we have had for a while (UB-free constexpr compile-time code) to things we’ve done recently (in draft C++26: erroneous behavior, bounds-hardened standard library, and contracts for functional safety) to proposals we’re actively pursuing next (in progress: Bjarne Stroustrup’s ... Read full article.