为什么我的结构没有定义？C语言中的队列

我需要一个非常简单的队列进行FIFO操作： 我已经使用过结构，所以我使用了一些为达到目的而修改的旧代码：但现在我的编译器不接受节点作为结构，并且我遇到了一些不兼容的指针问题。希望有人看到我遗漏的东西：

代码：

错误：

.6:2: error: unknown type name ‘Node’
  Node* next;
  ^
 In function ‘enqueue’:
:23:15: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
  Node* next = root->next;
               ^
c:27:9: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
    next = root->next;
         ^
c:29:14: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
   root->next = newTask;
              ^
c: In function ‘dequeue’:
c:38:11: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
   q->head = root->next;

Thx提前

---

Tim4497

当您声明字段

节点*next时，编译器不知道名为
节点的类型。它只知道
struct Node
@Eugene他键入了strutct，所以它应该只知道Node。@Fredrik这是在字段声明之后发生的。是的，刚刚解决了所有问题。。。谢谢：）但我很好奇，因为我在没有结构的情况下使用了它，它工作了？@Tim4497也许你有
typedef结构节点在此之前。或者使用C++编译器，（不确定）允许这样做。
.6:2: error: unknown type name ‘Node’
  Node* next;
  ^
 In function ‘enqueue’:
:23:15: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
  Node* next = root->next;
               ^
c:27:9: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
    next = root->next;
         ^
c:29:14: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
   root->next = newTask;
              ^
c: In function ‘dequeue’:
c:38:11: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
   q->head = root->next;