src/http/modules/ngx_http_upstream_hash_module.c:598: error: Uninitialized Value
  The value read from best_i was never initialized.

src/http/modules/ngx_http_upstream_hash_module.c:598:5: 
596.     ngx_http_upstream_rr_peers_unlock(hp->rrp.peers);
597. 
598.     n = best_i / (8 * sizeof(uintptr_t));
         ^
599.     m = (uintptr_t) 1 << best_i % (8 * sizeof(uintptr_t));
600. 
