链表分割故障a

Question

After I'd say about 500 entries, this linked list code seg faults.

while (item_temp->next != 0) {

Inside the loop, all it does is goes to the next item in the linked list.

When I look at it in gdb, here's what I get

(gdb) print item_temp
$1 = (struct item *) 0xc
(gdb) print item_temp->next
Cannot access memory at address 0xc

EDIT:

I allocate it like so:

struct item* item_temp = malloc(sizeof(struct item));

and then right before the loop I set it equal to the head of the linked list like so

    item_temp = table->buckets[code]->head;

And just for sake of making it known, before I try to reference the head, I make sure the head exists. I do that like so.

if (table->buckets[code]->head == 0)
{
    table->buckets[code]->head = item_add;
    table->occupied_buckets++;
}

Here's a sample of my code... if you need something else, please ask.

struct HT* add(struct HT* table, struct word *wrd, int(*alg)(struct word *wrd)) 
{
if ((double)table->entries / (double)table->num_buckets > .75)
{
    table = resize(table, alg);
}   
sort(wrd);
int code = alg(wrd);
code = code % table->num_buckets;
struct item* item_temp = malloc(sizeof(struct item));
struct item* item_add = malloc(sizeof(struct item));
item_add->wrd = wrd;
item_add->next = 0; 
if (table->buckets[code]->head == 0)
{
    table->buckets[code]->head = item_add;
    table->occupied_buckets++;
}
else
{
    item_temp = table->buckets[code]->head;
    while (item_temp->next != 0) {
        item_temp = item_temp->next;
    }
    item_temp->next = item_add;
}
table->buckets[code]->num_items++;
table->entries++;
if (table->buckets[code]->num_items > table->largest_bucket)
{
    table->largest_bucket = table->buckets[code]->num_items;
}
return table;
   }

Answer 1

From your question, it is clear that item_temp is pointing to location 0xc and de-referencing next is causing the code to access an invalid address and hence, the segmentation fault.

item_temp = table->buckets[code]->head; is evaluating to 0xc .