A little bit further down, he shows how to avoid using the return stack also, to use no stack at all. Also, by "return stack", he isn't referring to the mechan

A little bit further down, he shows how to avoid using the return stack also, to use no stack at all. Also, by "return stack", he isn't referring to the mechanism for returning values, he is referring to the mechanism for knowing which address to jump (return) to when a function is finished. In x86, this is still done with a stack, but the stack modifications are done "behind the scenes" by the call/ret instructions.