Interestingly, AUTOSAR C++14 Guidance (https://www.autosar.org/fileadmin/standards/R22-11/AP/AUTOSA...) had a "Rule A15-4-4 (required, implementation, automated) A declaration of non-throwing function shall contain noexcept specification." which was thankfully removed in MISRA C++2023 (the latest guidance for C++17, can't give a link, it's a paid document), - it mandates it only for a few special functions (destructors, move constructors/assignments and a few more).