From d75cbf2338f098a9c2143c94a9db8ddce68699b4 Mon Sep 17 00:00:00 2001
From: Dean Lee <deanlee3@gmail.com>
Date: Sat, 22 Oct 2022 01:33:13 +0800
Subject: [PATCH] Cabana: fix segfault on exit (#26193)

fix segfault on exit
---
 tools/cabana/mainwin.cc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/cabana/mainwin.cc b/tools/cabana/mainwin.cc
index 60a1f7a3a..d0e171c86 100644
--- a/tools/cabana/mainwin.cc
+++ b/tools/cabana/mainwin.cc
@@ -10,7 +10,7 @@
 
 static MainWindow *main_win = nullptr;
 void qLogMessageHandler(QtMsgType type, const QMessageLogContext &context, const QString &msg) {
-  main_win->showStatusMessage(msg);
+  if (main_win) main_win->showStatusMessage(msg);
 }
 
 MainWindow::MainWindow() : QWidget() {
@@ -118,6 +118,7 @@ void MainWindow::dockCharts(bool dock) {
 }
 
 void MainWindow::closeEvent(QCloseEvent *event) {
+  main_win = nullptr;
   if (floating_window)
     floating_window->deleteLater();
   QWidget::closeEvent(event);