Is there a C++ proposal to add mandatory bounds checks to methods like pop_back? If modern C++ is serious about getting memory safety, UB like this should be changed to have a run-time check and abort.

This is even backwards compatible, cheap or zero cost — if it's used in a loop that checks for non-empty length, the condition could be propagated and the redundant check optimized out.

I assume it won't get fixed, because from what I've seen so far if there is even slightest whiff of a performance overhead, modern C++ still chooses unsafety. If there's any inertia or backwards compatibility worry, even if it's a spacebar-heater, modern C++ still chooses to keep the old unsafety. Safety is still not a priority.