The POSIX description of the insque() function says that "If the queue is to be 
used as a linear list, invoking insque(&element, NULL), where element is the 
initial element of the queue, shall initialize the forward and backward 
pointers of element to null pointers."
However this function in the current glibc causes the segmentation fault if the 
second parameter is NULL.

Example of the code:
#include <stdio.h>
#include <search.h>
	
typedef struct
{
    void* next;
    void* prev;
} Node;

int main()
{
    Node A;
    A.next = NULL;
    A.prev = NULL;
    insque(&A, NULL);
    return 0;
}