Why would you expect the NULL pointer check to do anything? The function, as given, is meaningless if `p` is NULL. The problem isn't that compilers are too ag

Why would you expect the NULL pointer check to do anything? The function, as given, is meaningless if `p` is NULL. The problem isn't that compilers are too aggressive in their optimization -- the problem is that people who are learning C don't usually learn what it means for the behavior of a program to be undefined.