src/http/ngx_http_upstream_round_robin.c:467: error: Integer Overflow L2
  ([0, +oo] - 1):unsigned64 by call to `ngx_rwlock_unlock`.

src/http/ngx_http_upstream_round_robin.c:450:16: Call
448.         /* there are several peers */
449. 
450.         peer = ngx_http_upstream_get_peer(rrp);
                    ^
451. 
452.         if (peer == NULL) {

src/http/ngx_http_upstream_round_robin.c:556:13: Assignment
  554. 
  555.         if (peer->effective_weight < peer->weight) {
  556.             peer->effective_weight++;
                   ^
  557.         }
  558. 

src/http/ngx_http_upstream_round_robin.c:465:5: Assignment
463.     pc->name = &peer->name;
464. 
465.     peer->conns++;
         ^
466. 
467.     ngx_http_upstream_rr_peers_unlock(peers);

src/http/ngx_http_upstream_round_robin.c:467:5: Call
465.     peer->conns++;
466. 
467.     ngx_http_upstream_rr_peers_unlock(peers);
         ^
468. 
469.     return NGX_OK;

src/core/ngx_rwlock.c:89:1: <LHS trace>
87. 
88. 
89. void
    ^
90. ngx_rwlock_unlock(ngx_atomic_t *lock)
91. {

src/core/ngx_rwlock.c:89:1: Parameter `*lock`
  87. 
  88. 
  89. void
      ^
  90. ngx_rwlock_unlock(ngx_atomic_t *lock)
  91. {

src/core/ngx_rwlock.c:94:5: Assignment
  92.     ngx_atomic_uint_t  readers;
  93. 
  94.     readers = *lock;
          ^
  95. 
  96.     if (readers == NGX_RWLOCK_WLOCK) {

src/core/ngx_rwlock.c:103:13: Binary operation: ([0, +oo] - 1):unsigned64 by call to `ngx_rwlock_unlock` 
  101.     for ( ;; ) {
  102. 
  103.         if (ngx_atomic_cmp_set(lock, readers, readers - 1)) {
                   ^
  104.             return;
  105.         }
