Original poster from SO here: there are some components that are doing schedule calculations, so in some parts there are quite a lot of time-related calculation

Original poster from SO here: there are some components that are doing schedule calculations, so in some parts there are quite a lot of time-related calculations, and performance can be important in these parts. Also, I see now that the sentence "Our C++ library currently uses time_t for storing time values" might have been misleading; by "storing" I meant "keeping in RAM and registers, for calculations" rather than "keeping in non-volatile memory, for archival".