src/http/ngx_http_upstream.c:2328: error: Integer Overflow L2
  ([0, `r->uri_changes`] - 1):unsigned32 by call to `ngx_http_upstream_intercept_errors`.

src/http/ngx_http_upstream.c:2193:1: Parameter `r->uri_changes`
2191. 
2192. 
2193. static void
      ^
2194. ngx_http_upstream_process_header(ngx_http_request_t *r, ngx_http_upstream_t *u)
2195. {

src/http/ngx_http_upstream.c:2324:13: Call
2322.     if (u->headers_in.status_n >= NGX_HTTP_SPECIAL_RESPONSE) {
2323. 
2324.         if (ngx_http_upstream_test_next(r, u) == NGX_OK) {
                  ^
2325.             return;
2326.         }

src/http/ngx_http_upstream.c:2379:1: Parameter `r->uri_changes`
  2377. 
  2378. 
  2379. static ngx_int_t
        ^
  2380. ngx_http_upstream_test_next(ngx_http_request_t *r, ngx_http_upstream_t *u)
  2381. {

src/http/ngx_http_upstream.c:2328:13: Call
2326.         }
2327. 
2328.         if (ngx_http_upstream_intercept_errors(r, u) == NGX_OK) {
                  ^
2329.             return;
2330.         }

src/http/ngx_http_upstream.c:2500:1: Parameter `r->uri_changes`
  2498. 
  2499. 
  2500. static ngx_int_t
        ^
  2501. ngx_http_upstream_intercept_errors(ngx_http_request_t *r,
  2502.     ngx_http_upstream_t *u)

src/http/ngx_http_upstream.c:2538:21: Call
  2536. 
  2537.                 if (h == NULL) {
  2538.                     ngx_http_upstream_finalize_request(r, u,
                            ^
  2539.                                                NGX_HTTP_INTERNAL_SERVER_ERROR);
  2540.                     return NGX_OK;

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_intercept_errors` 
          2382.     ngx_http_core_srv_conf_t  *cscf;
          2383. 
          2384.     r->uri_changes--;
                    ^
          2385. 
          2386.     if (r->uri_changes == 0) {
