链表printf("%d\n"，tasks_head->head->tid)分段错误

if (tasks_head != NULL && tasks_head->head != NULL) {
    printf("%d\n", tasks_head->head->tid);
} else {
    printf("Error: tasks_head or tasks_head->head is NULL\n");
}

typedef struct Node {
    int tid;
    struct Node* next;
} Node;

Node* tasks_head = NULL;

// 初始化链表头节点
Node* create_node(int tid) {
    Node* new_node = (Node*)malloc(sizeof(Node));
    if (new_node == NULL) {
        perror("Failed to allocate memory");
        exit(EXIT_FAILURE);
    }
    new_node->tid = tid;
    new_node->next = NULL;
    return new_node;
}

void initialize_list() {
    tasks_head = create_node(0); // 创建一个头节点
}

void add_node(int tid) {
    Node* new_node = create_node(tid);
    if (tasks_head == NULL) {
        tasks_head = new_node;
    } else {
        Node* current = tasks_head;
        while (current->next != NULL) {
            current = current->next;
        }
        current->next = new_node;
    }
}

void delete_node(int tid) {
    Node* current = tasks_head;
    Node* previous = NULL;

    while (current != NULL && current->tid != tid) {
        previous = current;
        current = current->next;
    }

    if (current == NULL) {
        printf("Node with tid %d not found\n", tid);
        return;
    }

    if (previous == NULL) {
        tasks_head = current->next;
    } else {
        previous->next = current->next;
    }

    free(current);
}