I’m facing memory leak issues while running my C program. I’ve used Valgrind to detect memory leaks, but I’m confused about how to resolve them. My program appears to be functioning correctly, but Valgrind reports memory leaks.

I believe the memory leaks are coming from my main function. Although I know I should deallocate the h1 hashtable, I cannot do it outside the loop because it’s not defined there. If I attempt to do it inside the loop, it would be incorrect because I’m assigning h to h1, and if I deallocate h, h1 would then be pointing to an undefined area.

int main(int argc, char *argv[]) {
    for (int k = 1; k < argc; ++k) {
        const char *t = argv[k];
        printf("t%st", t);
    }
    hashtable *h1 = file_to_hashtable(argv[1]);
    if (h1 == NULL) {
        fprintf(stderr, "Error while creating hashtable n");
        return EXIT_FAILURE;
    }
    for (int i = 2; i < argc; ++i) {
        hashtable *h2 = file_to_hashtable(argv[i]);
        if (h2 == NULL) {
            hashtable_dispose(&h1);
            fprintf(stderr, "Error while creating hashtable n");
            return EXIT_FAILURE;
        }
        hashtable *h = merge_hashtables(h1, h2);
        if (h == NULL) {
            hashtable_dispose(&h1);
            hashtable_dispose(&h2);
            fprintf(stderr, "Error while creating hashtable n");
            return EXIT_FAILURE;
        }
        hashtable_dispose(&h2);
        h1 = h;
    }
    size_t k = 0;
    while (k < POW2(h1->lbnslots)) {
        cell *t = h1->hasharray[k];
        while (t != NULL) {
            const flword_occur *v = t->valref;
            int file_count = 0;
            for (int i = 1; i < argc; ++i) {
                hashtable *ht = file_to_hashtable(argv[i]);
                if (ht == NULL) {
                    hashtable_dispose(&h1);
                    fprintf(stderr, "Error while creating hashtable n");
                    return EXIT_FAILURE;
                }
                if (hashtable_search(ht, v->val) != NULL) {
                    file_count++;
                }
                hashtable_dispose(&ht);
            }
            if (file_count == 1) {
                printf("n%st%dn", v->val, v->occur);
                free(v->val);
                free((void *) v);
            }
            t = t->next;
        }
        ++k;
    }
    hashtable_dispose(&h1);
    printf("n");
    return EXIT_SUCCESS;
}