812                 /* As length, use a value smaller than FIRSTBITS for the head table,  in HuffmanTree_makeTable()
984         /*sum of the weights of the head nodes of the previous lookahead chains.*/  in boundaryPM()
1578     int * head; /*hash value to head circular pos - can be outdated if went around window*/  member
1585     int * headz; /*similar to head, but for chainz*/
1593     hash->head = (int *)lodepng_malloc(sizeof(int) * HASH_NUM_VALUES);  in hash_init()
1601 …  if(!hash->head || !hash->chain || !hash->val  || !hash->headz || !hash->chainz || !hash->zeros) {  in hash_init()
1606     for(i = 0; i != HASH_NUM_VALUES; ++i) hash->head[i] = -1;  in hash_init()
1618     lodepng_free(hash->head);  in hash_cleanup()
1665     if(hash->head[hashval] != -1) hash->chain[wpos] = hash->head[hashval];  in updateHashChain()
1666     hash->head[hashval] = (int)wpos;  in updateHashChain()
1800 …hash->head[hashval] = -1; /*the same hashchain update will be done, this ensures no wrong alterati…  in encodeLZ77()