我可以在VS2013中正式使用free()吗？

Question

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define TSIZE 45
struct film{
    char title[TSIZE];
    int rating;
    struct film *next;
};

int main(void)
{
    struct film *head = NULL;
    struct film *prev, *current;
    char input[TSIZE];

    puts("Enter first movie title:");
    while (gets(input) != NULL && input[0] != '\0')
    {
        current = (struct film*)malloc(sizeof(struct film));
        if (head == NULL)
            head = current;
        else
            prev->next = current;
        current->next = NULL;
        strcpy(current->title, input);
        puts("Enter your rating (0 - 10):");
        scanf("%d", &current->rating);
        while (getchar() != '\n')
            continue;
        puts("Enter next movie title(empty line to stop):");
        prev = current;

    }

    if (head == NULL)
        printf("No data entered.");
    else
        printf("Here is the movie list:\n");
    current = head;
    while (current != NULL)
    {
        printf("Movie: %s Rating: %d\n", current->title, current->rating);
        current = current->next;
    }
    current = head;
    while (current != NULL)
    {
        free(current);
        printf("hehe.\n");
        current = current->next;
    }
    printf("Bye!\n");

    return 0;
}    

为什么这段代码不能在VS 2013中正式使用？难道只是因为使用了free()函数，上面的代码就无法工作了吗？也许free()无法在VS2013中正式工作？？？

很抱歉发布整个代码，但系统说由于缺乏详细信息，我无法提交此问题......

Answer 1

您在释放之后访问指针current，这是未定义的行为。改变

while (current != NULL)
{
    free(current);
    printf("hehe.\n");
    current = current->next;
}

至

while (current != NULL)
{
    struct film *tmp = current;
    printf("hehe.\n");
    current = current->next;
    free(tmp);
}

请注意，您根本不应该使用 gets，因为它已从最近的 C 标准 C11 中删除，并且因其缓冲区溢出问题而臭名昭著。使用fgets()相反。

另外，不要强制转换 malloc family functions 的结果.