Subclause 6.10.3.4 [basic.start.term] paragraph 7 is a restriction on the use of the standard library that should be moved to the library section:

If there is a use of a standard library object or function not permitted within signal handlers (17.14 [support.runtime]) that does not happen before (6.10.2 [intro.multithread]) completion of destruction of objects with static storage duration and execution of std::atexit registered functions (17.5 [support.start.term]), the program has undefined behavior. [Note 3: If there is a use of an object with static storage duration that does not happen before the object's destruction, the program has undefined behavior. Terminating every thread before a call to std::exit or the exit from main is sufficient, but not necessary, to satisfy these requirements. These requirements permit thread managers as static-storage-duration objects. —end note]