Define structure dynamically when macro is defined

struct packet {
	char type;
};

#define TAILQ_HEAD(name, type)						\
struct name {								\
	struct type *tqh_first;	/* first element */			\
	struct type **tqh_last;	/* addr of last next element */		\
}

void test()
{
    TAILQ_HEAD(, packet) outgoing; // The label of the structure is NULL
    TAILQ_HEAD(xxx, packet) outgoing1; // The label of the structure is xxx
}