> And yes, if I am calling the shots, bounds checking are enabled in release builds. No disagreement there. But I'd prefer to turn it on across the board via c

> And yes, if I am calling the shots, bounds checking are enabled in release builds. No disagreement there. But I'd prefer to turn it on across the board via compiler flag rather than pull in a special library for it and remember to use that library consistently. And if that's the case, I don't see std::span as any more problematic on this front than the rest of the standard library. (Yes, I know, GSL isn't really a special library on Windows. But anywhere else, it is.)