C中的棘手段错误

Question

我正在尝试为我的大学任务运行一个C项目，我在线路上遇到了一个seg故障“while（current-＆gt; next！= NULL）{”在以下代码段中：

FILE* f = fileOpen("test.txt");
if (f != NULL){
    functionList = fileReadToMemory(f, &graphParams);//functionList is a pointer to the first value of the linked list it creates
    current = functionList;

    while (current->next != NULL) {
        printf("%d %d %d %s", current->red, current->green, current->blue, current->expression);//Prints value of linked list
        current = current -> next;
    }
}

gdb给我的错误如下：

Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x000000000000003a
0x0000000100000b30 in main () at main.c:23
23          while (current->next != NULL) {

我做错了什么？

提前致谢！

Answer 1

你需要做

while (current != NULL) 

而不是

current->next != NULL 

因为列表中的最后一个元素会导致段错误。