src/http/ngx_http_upstream.c:718: error: Integer Overflow L2
  ([0, `r->uri_changes`] - 1):unsigned32 by call to `ngx_http_upstream_connect`.

src/http/ngx_http_upstream.c:538:1: Parameter `r->uri_changes`
536. 
537. 
538. static void
     ^
539. ngx_http_upstream_init_request(ngx_http_request_t *r)
540. {

src/http/ngx_http_upstream.c:718:13: Call
716.             }
717. 
718.             ngx_http_upstream_connect(r, u);
                 ^
719. 
720.             return;

src/http/ngx_http_upstream.c:1482:1: Parameter `r->uri_changes`
  1480. 
  1481. 
  1482. static void
        ^
  1483. ngx_http_upstream_connect(ngx_http_request_t *r, ngx_http_upstream_t *u)
  1484. {

src/http/ngx_http_upstream.c:1522:9: Call
  1520.     if (rc == NGX_BUSY) {
  1521.         ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "no live upstreams");
  1522.         ngx_http_upstream_next(r, u, NGX_HTTP_UPSTREAM_FT_NOLIVE);
                ^
  1523.         return;
  1524.     }

src/http/ngx_http_upstream.c:4083:1: Parameter `r->uri_changes`
    4081. 
    4082. 
    4083. static void
          ^
    4084. ngx_http_upstream_next(ngx_http_request_t *r, ngx_http_upstream_t *u,
    4085.     ngx_uint_t ft_type)

src/http/ngx_http_upstream.c:4155:9: Call
    4153. 
    4154.     if (r->connection->error) {
    4155.         ngx_http_upstream_finalize_request(r, u,
                  ^
    4156.                                            NGX_HTTP_CLIENT_CLOSED_REQUEST);
    4157.         return;

src/http/ngx_http_upstream.c:4247:1: Parameter `r->uri_changes`
      4245. 
      4246. 
      4247. static void
            ^
      4248. ngx_http_upstream_finalize_request(ngx_http_request_t *r,
      4249.     ngx_http_upstream_t *u, ngx_int_t rc)

src/http/ngx_http_upstream.c:4258:9: Call
      4256.     if (u->cleanup == NULL) {
      4257.         /* the request was already finalized */
      4258.         ngx_http_finalize_request(r, NGX_DONE);
                    ^
      4259.         return;
      4260.     }

src/http/ngx_http_request.c:2307:1: Parameter `r->uri_changes`
        2305. 
        2306. 
        2307. void
              ^
        2308. ngx_http_finalize_request(ngx_http_request_t *r, ngx_int_t rc)
        2309. {

src/http/ngx_http_request.c:2345:13: Call
        2343.         || c->error)
        2344.     {
        2345.         if (ngx_http_post_action(r) == NGX_OK) {
                          ^
        2346.             return;
        2347.         }

src/http/ngx_http_request.c:3391:1: Parameter `r->uri_changes`
          3389. 
          3390. 
          3391. static ngx_int_t
                ^
          3392. ngx_http_post_action(ngx_http_request_t *r)
          3393. {

src/http/ngx_http_request.c:3418:9: Call
          3416. 
          3417.     if (clcf->post_action.data[0] == '/') {
          3418.         ngx_http_internal_redirect(r, &clcf->post_action, NULL);
                        ^
          3419. 
          3420.     } else {

src/http/ngx_http_core_module.c:2378:1: <LHS trace>
2376. 
2377. 
2378. ngx_int_t
      ^
2379. ngx_http_internal_redirect(ngx_http_request_t *r,
2380.     ngx_str_t *uri, ngx_str_t *args)

src/http/ngx_http_core_module.c:2378:1: Parameter `r->uri_changes`
            2376. 
            2377. 
            2378. ngx_int_t
                  ^
            2379. ngx_http_internal_redirect(ngx_http_request_t *r,
            2380.     ngx_str_t *uri, ngx_str_t *args)

src/http/ngx_http_core_module.c:2384:5: Binary operation: ([0, r->uri_changes] - 1):unsigned32 by call to `ngx_http_upstream_connect` 
            2382.     ngx_http_core_srv_conf_t  *cscf;
            2383. 
            2384.     r->uri_changes--;
                      ^
            2385. 
            2386.     if (r->uri_changes == 0) {
