}
#define register_callback(cb, arg) \
_register_callback(typesafe_cb_postargs(void, void *, (cb), (arg), int), (arg))
static void my_callback(char *p, int x)
{
}
#define register_callback(cb, arg) \
_register_callback(typesafe_cb_postargs(void, void *, (cb), (arg), int), (arg))
static void my_callback(char *p, int x)
{