src/http/modules/ngx_http_limit_req_module.c:435: error: Integer Overflow L2
  ([0, +oo] - [0, 15]):unsigned64 by call to `ngx_slab_alloc_locked`.

src/http/modules/ngx_http_limit_req_module.c:435:12: Call
433.     ngx_http_limit_req_expire(ctx, 1);
434. 
435.     node = ngx_slab_alloc_locked(ctx->shpool, size);
                ^
436. 
437.     if (node == NULL) {

src/core/ngx_slab.c:156:1: <LHS trace>
154. 
155. 
156. void *
     ^
157. ngx_slab_alloc_locked(ngx_slab_pool_t *pool, size_t size)
158. {

src/core/ngx_slab.c:156:1: Global `ngx_pagesize_shift`
  154. 
  155. 
  156. void *
       ^
  157. ngx_slab_alloc_locked(ngx_slab_pool_t *pool, size_t size)
  158. {

src/core/ngx_slab.c:289:13: Binary operation: ([0, +oo] - [0, 15]):unsigned64 by call to `ngx_slab_alloc_locked` 
  287.         } else { /* shift > ngx_slab_exact_shift */
  288. 
  289.             n = ngx_pagesize_shift - (page->slab & NGX_SLAB_SHIFT_MASK);
                   ^
  290.             n = 1 << n;
  291.             n = ((uintptr_t) 1 << n) - 1;
