我一直收到一个collect2：错误：ld返回1退出状态
我有一点问题。 每次我尝试编译程序时，我都会收到“collect2：错误：ld返回1退出状态”。 我搜索了这个，查看了示例，并发现它通常发生在未正确使用头文件时; 但是，我没有在我的代码中使用头文件，所以我不确定为什么这样做。 我认为这对于那些得到此错误并且不理解原因的人会有所帮助。 我知道我的代码中存在很多错误，但我试图找到可以编译它的地方并解决所有问题。 谢谢一堆！
#include #include struct node_t { double x; struct node_t *next; }; struct node_t *create_node(double n); void print_node (struct node_t * node ); void print_list (struct node_t * head ); struct node_t * insert_head (struct node_t *head , struct node_t * node ); struct node_t * insert_tail (struct node_t *head , struct node_t * node ); struct node_t * insert_middle (struct node_t *head , struct node_t *node , int pos ); int count_nodes (struct node_t * head ); struct node_t * delete_node (struct node_t *head , double n); void delete_list (struct node_t * head ); int main (void) { double n; int pos; /** Asks the user what they would like to do. */ printf("Please select an option: "); printf("1. Enter a number "); printf("2. Delete a number "); printf("3. Print all numbers "); printf("4. Tell how many items in the list "); printf("5. End program "); printf("Please enter your choice (1, 2, 3, 4, 5): "); while ((tmp = getchar()) != '\n') in = tmp; /** Tells the compiler to use the number that the use put in. */ switch (in){ case '1': {/** If the user chooses Enter a Number, go through this process. */ printf("1. Enter item at head of list "); printf("2. Enter item in middle of list "); printf("3. Enter item at tail of list "); printf("Please enter your choice (1,2,3): "); while ((tmp = getchar()) != '\n') in = tmp; switch (in) { case '1':{ printf("Enter the number to be entered at head: "); fgets(s, 1024, stdin); struct node_t * create_node (double n); struct node_t *insert_head(struct node_t *head, struct node_t *node); break; } case '2':{ printf("Enter the number to be entered in middle: "); fgets(s, 1024, stdin); struct node_t * create_node (double n); struct node_t * insert_middle (struct node_t *head , struct node_t *node , int pos); break; } case '3':{ printf("Enter the number to be entered at tail: "); fgets(s, 1024, stdin); struct node_t * create_node (double n); struct node_t *insert_tail(struct node_t *tail, struct node_t *node); break; } break; } } case '2':{/** If the user selected Delete a Number, go through this process. */ printf("Enter the node that needs to be deleted: "); fgets(s, 1024, stdin); struct node_t * delete_node (struct node_t *head , double n); break; } case '3':{/** If the user selected Print All Numbers, go through this process. */ //void print_list (struct node_t *head) break; } case '4':{ /** If the user selected Tell How Many Items in the List, go through this process. */ int count_nodes (struct node_t * head ); break; } case '5':{ /** If the user selected End Program, go through this process. */ return 1; break; } } return 0; } /** Creates a new node * @param double n, a number n * @return pointer */ struct node_t * create_node (double n) { struct node_t *p = malloc (size of (struct node_t)) p -> x = n; p -> next = NULL; /*initializes pointer to null*/ return p; } /** Prints the nodes * @param struct node_t *node */ //void print_node (struct node_t *node ) //{ // prints out the node and the address of the node // print(*node, &node) //} /** Prints list * @param struct node_t *head */ //void print_list (struct node_t *head) //{ // print contents of list. both the doubles and the address. // while (pointer is pointing to something, keep going through the list. ) // print(nodes in list, address of nodes ) //} /** Inserts a node at the head * @param struct node_t *head, the structure where head is. * @param struct node_t *node, the structure where node is. * @return head. */ struct node_t *insert_head(struct node_t *head, struct node_t *node) { node-> next = head; head = node; return head; } /** Inserts a node at the tail. * @param struct node_t *tail, the structure where tail is. * @param struct node_t *node, the structure where node is. * @return head. */ struct node_t *insert_tail(struct node_t *tail, struct node_t *node) { struct node_t *p = head; if (head == NULL) head = node; return head; while (p->next ! = NULL) p = p-> next; p-> next = node; return head; } /** Inserts a node at the middle. * @param struct node_t *head, the structure where head is. * @param struct node_t *node, the structure where node is. * @param int pos, the position of the current node. * @return head. */ struct node_t * insert_middle (struct node_t *head , struct node_t *node , int pos); { int pos = 1; struct node_t *p = head; *head = pos, pos = 1; if (pos > SIZE ) p-> next = node; else if (pos next ! = NULL) return count; if (head == NULL) count = 0; return count; } /** Deletes nodes * @param struct node_t *head, the structure where head is. * @param double n, a number n. * @return head. */ struct node_t * delete_node (struct node_t *head , double n); { if (node == head) free head; p->next = head; //head now points to the pointer that was next after the node that was deleted else if (node == middle) free node; p = p->next //pointer before node that was deleted now points to node that was after deleted node else if (node == tail) free p = p->next = node; //free the last node that holds data. The node before it now points to NULL p->next = NULL; else printf("Error\n") return head; } /** Deletes list * @param struct node_t *head, the structure where head is. * @return head. */ void delete_list (struct node_t * head ); { while((p->next ! = NULL) free head; //This will lose all memory after head. head == NULL; if (head == NULL) return 0; return 0; } 那是链接器失败的时候。
您可能在文件顶部的前向声明的签名与下面的实现之间存在不匹配。 链接器找不到其中一个函数。