src/http/ngx_http_upstream.c:1638: error: Integer Overflow L2
  ([0, `r->uri_changes`] - 1):unsigned32 by call to `ngx_http_upstream_send_response`.

src/http/ngx_http_upstream.c:1493:1: Parameter `r->uri_changes`
1491. 
1492. 
1493. static void
      ^
1494. ngx_http_upstream_process_header(ngx_http_request_t *r, ngx_http_upstream_t *u)
1495. {

src/http/ngx_http_upstream.c:1633:9: Call
1631.     }
1632. 
1633.     if (ngx_http_upstream_process_headers(r, u) != NGX_OK) {
              ^
1634.         return;
1635.     }

src/http/ngx_http_upstream.c:1841:1: Parameter `r->uri_changes`
  1839. 
  1840. 
  1841. static ngx_int_t
        ^
  1842. ngx_http_upstream_process_headers(ngx_http_request_t *r, ngx_http_upstream_t *u)
  1843. {

src/http/ngx_http_upstream.c:1638:9: Call
1636. 
1637.     if (!r->subrequest_in_memory) {
1638.         ngx_http_upstream_send_response(r, u);
              ^
1639.         return;
1640.     }

src/http/ngx_http_upstream.c:2042:1: Parameter `r->uri_changes`
  2040. 
  2041. 
  2042. static void
        ^
  2043. ngx_http_upstream_send_response(ngx_http_request_t *r, ngx_http_upstream_t *u)
  2044. {

src/http/ngx_http_upstream.c:2055:9: Call
  2053. 
  2054.     if (rc == NGX_ERROR || rc > NGX_OK || r->post_action) {
  2055.         ngx_http_upstream_finalize_request(r, u, rc);
                ^
  2056.         return;
  2057.     }

src/http/ngx_http_upstream.c:2974:1: Parameter `r->uri_changes`
    2972. 
    2973. 
    2974. static void
          ^
    2975. ngx_http_upstream_finalize_request(ngx_http_request_t *r,
    2976.     ngx_http_upstream_t *u, ngx_int_t rc)

src/http/ngx_http_upstream.c:3093:5: Call
    3091.     }
    3092. 
    3093.     ngx_http_finalize_request(r, rc);
              ^
    3094. }
    3095. 

src/http/ngx_http_request.c:1882:1: Parameter `r->uri_changes`
      1880. 
      1881. 
      1882. void
            ^
      1883. ngx_http_finalize_request(ngx_http_request_t *r, ngx_int_t rc)
      1884. {

src/http/ngx_http_request.c:2053:9: Call
      2051.     }
      2052. 
      2053.     if (ngx_http_post_action(r) == NGX_OK) {
                    ^
      2054.         return;
      2055.     }

src/http/ngx_http_request.c:2889:1: Parameter `r->uri_changes`
        2887. 
        2888. 
        2889. static ngx_int_t
              ^
        2890. ngx_http_post_action(ngx_http_request_t *r)
        2891. {

src/http/ngx_http_request.c:2912:9: Call
        2910. 
        2911.     if (clcf->post_action.data[0] == '/') {
        2912.         ngx_http_internal_redirect(r, &clcf->post_action, NULL);
                      ^
        2913. 
        2914.     } else {

src/http/ngx_http_core_module.c:2463:1: <LHS trace>
2461. 
2462. 
2463. ngx_int_t
      ^
2464. ngx_http_internal_redirect(ngx_http_request_t *r,
2465.     ngx_str_t *uri, ngx_str_t *args)

src/http/ngx_http_core_module.c:2463:1: Parameter `r->uri_changes`
          2461. 
          2462. 
          2463. ngx_int_t
                ^
          2464. ngx_http_internal_redirect(ngx_http_request_t *r,
          2465.     ngx_str_t *uri, ngx_str_t *args)

src/http/ngx_http_core_module.c:2469:5: Binary operation: ([0, r->uri_changes] - 1):unsigned32 by call to `ngx_http_upstream_send_response` 
          2467.     ngx_http_core_srv_conf_t  *cscf;
          2468. 
          2469.     r->uri_changes--;
                    ^
          2470. 
          2471.     if (r->uri_changes == 0) {
