check thread whether joinable before join (#2019)

uupks · web-flow · commit b9b1468d15c7 · 2022-10-13T08:30:02.000-04:00
Signed-off-by: uupks &lt;uupks0325@gmail.com&gt;
diff --git a/rclcpp/src/rclcpp/signal_handler.cpp b/rclcpp/src/rclcpp/signal_handler.cpp
@@ -191,7 +191,9 @@ SignalHandler::uninstall()
     signal_handlers_options_ = SignalHandlerOptions::None;
     RCLCPP_DEBUG(get_logger(), "SignalHandler::uninstall(): notifying deferred signal handler");
     notify_signal_handler();
-    signal_handler_thread_.join();
+    if (signal_handler_thread_.joinable()) {
+      signal_handler_thread_.join();
+    }
     teardown_wait_for_signal();
   } catch (...) {
     installed_.exchange(true);
