What exactly is va_end for? Is it always necessary to call it?

Question

va_end - Macro to reset arg_ptr.

After accessing a variable argument list, the arg_ptr pointer is

Answer 1

In the common "parameters passed on the stack" implementation, I believe va_end() is usually nothing/empty/null. However, on platforms which have less traditional schemes, it becomes necessary. It's a "good practice" to include it to remain platform neutral.