C++ standard 3.6.2[5] since like forever... A return statement in main has the effect of leaving the main function (destroying any objects with automatic stora

C++ standard 3.6.2[5] since like forever... A return statement in main has the effect of leaving the main function (destroying any objects with automatic storage duration) and calling std::exit with the return value as the argument. If control reaches the end of main without encountering a return statement, the effect is that of executing return 0;