From df73f5a15dd9a48e69a0d38a7c7ef3142b1ada71 Mon Sep 17 00:00:00 2001
From: Dean Lee <deanlee3@gmail.com>
Date: Sat, 12 Nov 2022 02:34:25 +0800
Subject: [PATCH] Cabana: fix segfault on exit (#26465)

fix segfault on exit
old-commit-hash: 6cf9fff9193f3d61c81de65e88ba9ea908552062
---
 tools/cabana/detailwidget.cc | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tools/cabana/detailwidget.cc b/tools/cabana/detailwidget.cc
index 6d07727303..8549ed4641 100644
--- a/tools/cabana/detailwidget.cc
+++ b/tools/cabana/detailwidget.cc
@@ -102,7 +102,10 @@ DetailWidget::DetailWidget(ChartsWidget *charts, QWidget *parent) : charts(chart
   QObject::connect(tabbar, &QTabBar::tabCloseRequested, tabbar, &QTabBar::removeTab);
   QObject::connect(charts, &ChartsWidget::chartOpened, [this](const QString &id, const Signal *sig) { updateChartState(id, sig, true); });
   QObject::connect(charts, &ChartsWidget::chartClosed, [this](const QString &id, const Signal *sig) { updateChartState(id, sig, false); });
-  QObject::connect(undo_stack, &QUndoStack::indexChanged, [this]() { dbcMsgChanged(); });
+  QObject::connect(undo_stack, &QUndoStack::indexChanged, [this]() {
+    if (undo_stack->count() > 0)
+      dbcMsgChanged();
+  });
 }
 
 void DetailWidget::showTabBarContextMenu(const QPoint &pt) {