src/http/ngx_http_upstream.c:2453: error: Integer Overflow L2
  ([0, `r->main->count` + 1] - 1):unsigned32 by call to `ngx_http_upstream_process_upgraded`.

src/http/ngx_http_upstream.c:2384:1: Parameter `r->main->count`
2382. 
2383. 
2384. static void
      ^
2385. ngx_http_upstream_upgrade(ngx_http_request_t *r, ngx_http_upstream_t *u)
2386. {

src/http/ngx_http_upstream.c:2453:9: Call
2451.         || r->header_in->pos != r->header_in->last)
2452.     {
2453.         ngx_http_upstream_process_upgraded(r, 0, 1);
              ^
2454.     }
2455. }

src/http/ngx_http_upstream.c:2488:1: Parameter `r->main->count`
  2486. 
  2487. 
  2488. static void
        ^
  2489. ngx_http_upstream_process_upgraded(ngx_http_request_t *r,
  2490.     ngx_uint_t from_upstream, ngx_uint_t do_write)

src/http/ngx_http_upstream.c:2511:9: Call
  2509.         c->timedout = 1;
  2510.         ngx_connection_error(c, NGX_ETIMEDOUT, "client timed out");
  2511.         ngx_http_upstream_finalize_request(r, u, NGX_HTTP_REQUEST_TIME_OUT);
                ^
  2512.         return;
  2513.     }

src/http/ngx_http_upstream.c:3296:1: Parameter `r->main->count`
    3294. 
    3295. 
    3296. static void
          ^
    3297. ngx_http_upstream_finalize_request(ngx_http_request_t *r,
    3298.     ngx_http_upstream_t *u, ngx_int_t rc)

src/http/ngx_http_upstream.c:3425:9: Call
    3423. 
    3424.     if (r->header_only) {
    3425.         ngx_http_finalize_request(r, rc);
                  ^
    3426.         return;
    3427.     }

src/http/ngx_http_request.c:2198:1: Parameter `r->main->count`
      2196. 
      2197. 
      2198. void
            ^
      2199. ngx_http_finalize_request(ngx_http_request_t *r, ngx_int_t rc)
      2200. {

src/http/ngx_http_request.c:2365:9: Call
      2363.     }
      2364. 
      2365.     if (ngx_http_post_action(r) == NGX_OK) {
                    ^
      2366.         return;
      2367.     }

src/http/ngx_http_request.c:3256:1: <LHS trace>
3254. 
3255. 
3256. static ngx_int_t
      ^
3257. ngx_http_post_action(ngx_http_request_t *r)
3258. {

src/http/ngx_http_request.c:3256:1: Parameter `r->main->count`
        3254. 
        3255. 
        3256. static ngx_int_t
              ^
        3257. ngx_http_post_action(ngx_http_request_t *r)
        3258. {

src/http/ngx_http_request.c:3274:5: Binary operation: ([0, r->main->count + 1] - 1):unsigned32 by call to `ngx_http_upstream_process_upgraded` 
        3272.                    "post action: \"%V\"", &clcf->post_action);
        3273. 
        3274.     r->main->count--;
                  ^
        3275. 
        3276.     r->http_version = NGX_HTTP_VERSION_9;
