NGX_HTTP_UPSTREAM_IGN_EXPIRES  363 http/ngx_http_upstream.c     { ngx_string("Expires"), NGX_HTTP_UPSTREAM_IGN_EXPIRES },
NGX_HTTP_UPSTREAM_IGN_EXPIRES 3178 http/ngx_http_upstream.c     if (u->conf->ignore_headers & NGX_HTTP_UPSTREAM_IGN_EXPIRES) {