编译后提示下方注释出：可能使用了未初始化本地变量指针pt，但是在while循环中不是有定义吗？
要如何让修改？

#include<stdio.h>
struct employee
{
        int no;
        char name[20];
        struct employee *next;
};
struct employee *insert(struct employee *head, struct employee *pb)
{
        struct employee *pn, *pt;
        pn = head;
        if (pn == NULL)
        {
                head = pb;
                pb->next = NULL;
        }                                                                          
        else
        {
                while ((pn->no != pb->no)&&(pb->next != NULL))                           
                {
                        pt = pn;
                        pn = pn->next;
                }
                if (pn->no == pb->no)
                {
                        if (head == pn)
                                head = pb;
                        else
                                pt->next = pb;                                          //???????
                        pb->next = pn;
                }
                else
                {
                        pn->next = pb;
                        pb->next = NULL;
                }
        }
        return head;

随便整点数据测试的
#include <stdio.h>

struct employee
{
    int no;
    char name[20];
    struct employee *next;
};

struct employee *insert(struct employee *head, struct employee *pb)
{
    struct employee *pn, *pt;
    pn = head;
    pt = NULL;
    while (pn)
    {
        if (pn->no == pb->no)
        {
            pb->next = pn;
            break;
        }
        pt = pn;
        pn = pn->next;
    }
    if (pt)
        pt->next = pb;
    else
        head = pb;
    return head;
}

main()
{
    struct employee a[6] =
    {
        101, "a101", NULL,
        103, "a103", NULL,
        102, "a102", NULL,
        101, "a101", NULL,
        103, "a103", NULL,
        102, "a102", NULL
    };
    struct employee *head = NULL;
    int i;
    for (i=0; i<6; ++i)
       head = insert(head, &a[i]);
    struct employee *h;
    for (h=head; h; h=h->next)
        printf("%d\t%s\n",h->no, h->name);
}

谢谢，大佬。