Question

I have a structure like this

struct list
{
    struct list *next;

    int temp;
};

I use the following method to free

…. …. ….

// free linked list
struct list *head_list = NULL;
struct list *current_list = NULL;
struct list *prev_list = NULL;

current_list = head_list;
while (current_file_info_arr != NULL)
{
    prev_list = current_list;
    current_list = current_list->next;
    free(prev_list);
}   

I get the warning

Memory error
Use of memory after it is freed

Is there any good solution?

Answer 1

I think you just need to replace

while (current_file_info_arr != NULL)

with

while (current_list != NULL)

But that’s assuming you actually have a list in place – allocated/constructed previously – and head_list points to beginning of it. If head_list is NULL, like in your snippet:

struct list *head_list = NULL;

then the Memory error is not a surprise. You are trying to free NULL, which is an error, indeed.