src/http/ngx_http_upstream.c:4516: error: Uninitialized Value
  The value read from cv.lengths was never initialized.

src/http/ngx_http_upstream.c:4516:9: 
4514.     *plocal = local;
4515. 
4516.     if (cv.lengths) {
              ^
4517.         local->value = ngx_palloc(cf->pool, sizeof(ngx_http_complex_value_t));
4518.         if (local->value == NULL) {
