diff --git a/cartographer_rviz/cartographer_rviz/drawable_submap.h b/cartographer_rviz/cartographer_rviz/drawable_submap.h
index ea3b154..df8cc18 100644
--- a/cartographer_rviz/cartographer_rviz/drawable_submap.h
+++ b/cartographer_rviz/cartographer_rviz/drawable_submap.h
@@ -105,8 +105,8 @@ class DrawableSubmap : public QObject {
   ::rviz::Axes pose_axes_;
   ::rviz::MovableText submap_id_text_;
   std::chrono::milliseconds last_query_timestamp_ GUARDED_BY(mutex_);
-  bool query_in_progress_ = false GUARDED_BY(mutex_);
-  int metadata_version_ = -1 GUARDED_BY(mutex_);
+  bool query_in_progress_ GUARDED_BY(mutex_) = false;
+  int metadata_version_ GUARDED_BY(mutex_) = -1;
   std::future<void> rpc_request_future_;
   std::unique_ptr<::cartographer::io::SubmapTextures> submap_textures_
       GUARDED_BY(mutex_);