What many people don't expect is that if the compiler can prove that some function invokes undefined behavior, the compiler can emit no code for it at all--befo

What many people don't expect is that if the compiler can prove that some function invokes undefined behavior, the compiler can emit no code for it at all--before, during, and after the UB expression. Saying that writing past the end of an array could modify any other variable is one thing. Saying that writing past the end of an array could make your entire program do nothing is quite another.