always test root existence for access_log with variables
diff --git a/src/http/ngx_http_request.h b/src/http/ngx_http_request.h
index 1a4eae1..be22db6 100644
--- a/src/http/ngx_http_request.h
+++ b/src/http/ngx_http_request.h
@@ -469,6 +469,7 @@
     unsigned                          request_output:1;
     unsigned                          header_sent:1;
     unsigned                          expect_tested:1;
+    unsigned                          root_tested:1;
     unsigned                          done:1;
     unsigned                          utf8:1;