src/http/ngx_http_upstream.c:677: error: Integer Overflow L2
  ([0, `r->main->count` + 3] - 1):unsigned32 by call to `ngx_http_upstream_connect`.

src/http/ngx_http_upstream.c:521:1: Parameter `r->main->count`
519. 
520. 
521. static void
     ^
522. ngx_http_upstream_init_request(ngx_http_request_t *r)
523. {

src/http/ngx_http_upstream.c:677:13: Call
675.             }
676. 
677.             ngx_http_upstream_connect(r, u);
                 ^
678. 
679.             return;

src/http/ngx_http_upstream.c:1339:1: Parameter `r->main->count`
  1337. 
  1338. 
  1339. static void
        ^
  1340. ngx_http_upstream_connect(ngx_http_request_t *r, ngx_http_upstream_t *u)
  1341. {

src/http/ngx_http_upstream.c:1379:9: Call
  1377.     if (rc == NGX_BUSY) {
  1378.         ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "no live upstreams");
  1379.         ngx_http_upstream_next(r, u, NGX_HTTP_UPSTREAM_FT_NOLIVE);
                ^
  1380.         return;
  1381.     }

src/http/ngx_http_upstream.c:3939:1: Parameter `r->main->count`
    3937. 
    3938. 
    3939. static void
          ^
    3940. ngx_http_upstream_next(ngx_http_request_t *r, ngx_http_upstream_t *u,
    3941.     ngx_uint_t ft_type)

src/http/ngx_http_upstream.c:4002:9: Call
    4000. 
    4001.     if (r->connection->error) {
    4002.         ngx_http_upstream_finalize_request(r, u,
                  ^
    4003.                                            NGX_HTTP_CLIENT_CLOSED_REQUEST);
    4004.         return;

src/http/ngx_http_upstream.c:4083:1: Parameter `r->main->count`
      4081. 
      4082. 
      4083. static void
            ^
      4084. ngx_http_upstream_finalize_request(ngx_http_request_t *r,
      4085.     ngx_http_upstream_t *u, ngx_int_t rc)

src/http/ngx_http_upstream.c:4226:9: Call
      4224. 
      4225.     if (r->header_only) {
      4226.         ngx_http_finalize_request(r, rc);
                    ^
      4227.         return;
      4228.     }

src/http/ngx_http_request.c:2261:1: <LHS trace>
2259. 
2260. 
2261. void
      ^
2262. ngx_http_finalize_request(ngx_http_request_t *r, ngx_int_t rc)
2263. {

src/http/ngx_http_request.c:2261:1: Parameter `r->main->count`
        2259. 
        2260. 
        2261. void
              ^
        2262. ngx_http_finalize_request(ngx_http_request_t *r, ngx_int_t rc)
        2263. {

src/http/ngx_http_request.c:2352:13: Binary operation: ([0, r->main->count + 3] - 1):unsigned32 by call to `ngx_http_upstream_connect` 
        2350.         if (r == c->data) {
        2351. 
        2352.             r->main->count--;
                          ^
        2353. 
        2354.             if (!r->logged) {
