c/variadic/va list

is a complete object type suitable for holding the information needed by the macros va_start, va_copy, va_arg, and va_end.

If a instance is created, passed to another function, and used via va_arg in that function, then any subsequent use in the calling function should be preceded by a call to va_end.

It is legal to pass a pointer to a object to another function and then use that object after the function returns.