As far as I know, the promotion to word size (now 32 bit) still happens. Also if you have more than a fixed number of params (defined by the platform ABI), para

As far as I know, the promotion to word size (now 32 bit) still happens. Also if you have more than a fixed number of params (defined by the platform ABI), parameters are still pushed on the stack. You can't push 8 or 16 bit values on the stack. The stack pointer is always a multiple of 4. The interesting thing is that with K&R C a function declaration/prototype is optional. That means you can call a function that the compiler has not even seen. Mismatches in parameter/return types (which are optional and default to int in declarations as well) are normally not a problem, because of the aforementioned promotion. If you have the declaration, then the compiler will at least let you know about wrong number of arguments.