src/http/ngx_http_upstream.c:541: error: Integer Overflow L2
  ([0, `r->uri_changes`] - 1):unsigned32 by call to `ngx_http_upstream_connect`.

src/http/ngx_http_upstream.c:421:1: Parameter `r->uri_changes`
419. 
420. 
421. static void
     ^
422. ngx_http_upstream_init_request(ngx_http_request_t *r)
423. {

src/http/ngx_http_upstream.c:541:13: Call
539.             }
540. 
541.             ngx_http_upstream_connect(r, u);
                 ^
542. 
543.             return;

src/http/ngx_http_upstream.c:1039:1: Parameter `r->uri_changes`
  1037. 
  1038. 
  1039. static void
        ^
  1040. ngx_http_upstream_connect(ngx_http_request_t *r, ngx_http_upstream_t *u)
  1041. {

src/http/ngx_http_upstream.c:1170:5: Call
  1168. #endif
  1169. 
  1170.     ngx_http_upstream_send_request(r, u);
            ^
  1171. }
  1172. 

src/http/ngx_http_upstream.c:1309:1: Parameter `r->uri_changes`
    1307. 
    1308. 
    1309. static void
          ^
    1310. ngx_http_upstream_send_request(ngx_http_request_t *r, ngx_http_upstream_t *u)
    1311. {

src/http/ngx_http_upstream.c:1380:9: Call
    1378.          */
    1379. 
    1380.         ngx_http_upstream_process_header(r, u);
                  ^
    1381.         return;
    1382.     }

src/http/ngx_http_upstream.c:1432:1: Parameter `r->uri_changes`
      1430. 
      1431. 
      1432. static void
            ^
      1433. ngx_http_upstream_process_header(ngx_http_request_t *r, ngx_http_upstream_t *u)
      1434. {

src/http/ngx_http_upstream.c:1563:13: Call
      1561.         }
      1562. 
      1563.         if (ngx_http_upstream_test_next(r, u) == NGX_OK) {
                        ^
      1564.             return;
      1565.         }

src/http/ngx_http_upstream.c:1619:1: Parameter `r->uri_changes`
        1617. 
        1618. 
        1619. static ngx_int_t
              ^
        1620. ngx_http_upstream_test_next(ngx_http_request_t *r, ngx_http_upstream_t *u)
        1621. {

src/http/ngx_http_upstream.c:1634:13: Call
        1632. 
        1633.         if (u->peer.tries > 1 && (u->conf->next_upstream & un->mask)) {
        1634.             ngx_http_upstream_next(r, u, un->mask);
                          ^
        1635.             return NGX_OK;
        1636.         }

src/http/ngx_http_upstream.c:2709:1: Parameter `r->uri_changes`
          2707. 
          2708. 
          2709. static void
                ^
          2710. ngx_http_upstream_next(ngx_http_request_t *r, ngx_http_upstream_t *u,
          2711.     ngx_uint_t ft_type)

src/http/ngx_http_upstream.c:2766:9: Call
          2764. 
          2765.     if (r->connection->error) {
          2766.         ngx_http_upstream_finalize_request(r, u,
                        ^
          2767.                                            NGX_HTTP_CLIENT_CLOSED_REQUEST);
          2768.         return;

src/http/ngx_http_upstream.c:2849:1: Parameter `r->uri_changes`
            2847. 
            2848. 
            2849. static void
                  ^
            2850. ngx_http_upstream_finalize_request(ngx_http_request_t *r,
            2851.     ngx_http_upstream_t *u, ngx_int_t rc)

src/http/ngx_http_upstream.c:2959:5: Call
            2957.     }
            2958. 
            2959.     ngx_http_finalize_request(r, rc);
                      ^
            2960. }
            2961. 

src/http/ngx_http_request.c:1856:1: Parameter `r->uri_changes`
              1854. 
              1855. 
              1856. void
                    ^
              1857. ngx_http_finalize_request(ngx_http_request_t *r, ngx_int_t rc)
              1858. {

src/http/ngx_http_request.c:2027:9: Call
              2025.     }
              2026. 
              2027.     if (ngx_http_post_action(r) == NGX_OK) {
                            ^
              2028.         return;
              2029.     }

src/http/ngx_http_request.c:2856:1: Parameter `r->uri_changes`
                2854. 
                2855. 
                2856. static ngx_int_t
                      ^
                2857. ngx_http_post_action(ngx_http_request_t *r)
                2858. {

src/http/ngx_http_request.c:2879:9: Call
                2877. 
                2878.     if (clcf->post_action.data[0] == '/') {
                2879.         ngx_http_internal_redirect(r, &clcf->post_action, NULL);
                              ^
                2880. 
                2881.     } else {

src/http/ngx_http_core_module.c:2275:1: <LHS trace>
2273. 
2274. 
2275. ngx_int_t
      ^
2276. ngx_http_internal_redirect(ngx_http_request_t *r,
2277.     ngx_str_t *uri, ngx_str_t *args)

src/http/ngx_http_core_module.c:2275:1: Parameter `r->uri_changes`
                  2273. 
                  2274. 
                  2275. ngx_int_t
                        ^
                  2276. ngx_http_internal_redirect(ngx_http_request_t *r,
                  2277.     ngx_str_t *uri, ngx_str_t *args)

src/http/ngx_http_core_module.c:2281:5: Binary operation: ([0, r->uri_changes] - 1):unsigned32 by call to `ngx_http_upstream_connect` 
                  2279.     ngx_http_core_srv_conf_t  *cscf;
                  2280. 
                  2281.     r->uri_changes--;
                            ^
                  2282. 
                  2283.     if (r->uri_changes == 0) {
