diff --git a/src/plugins/projectexplorer/appoutputpane.cpp b/src/plugins/projectexplorer/appoutputpane.cpp
index fa4d4f1c19b..73b28c176e1 100644
--- a/src/plugins/projectexplorer/appoutputpane.cpp
+++ b/src/plugins/projectexplorer/appoutputpane.cpp
@@ -321,7 +321,7 @@ void AppOutputPane::updateCloseActions()
 bool AppOutputPane::aboutToClose() const
 {
     return Utils::allOf(m_runControlTabs, [](const RunControlTab &rt) {
-        return !rt.runControl->isRunning() || rt.runControl->promptToStop();
+        return !rt.runControl || !rt.runControl->isRunning() || rt.runControl->promptToStop();
     });
 }
 
@@ -507,9 +507,9 @@ void AppOutputPane::setBehaviorOnOutput(RunControl *rc, AppOutputPane::BehaviorO
 void AppOutputPane::reRunRunControl()
 {
     const int index = currentIndex();
-    QTC_ASSERT(index != -1 && !m_runControlTabs.at(index).runControl->isRunning(), return);
-
-    RunControlTab &tab = m_runControlTabs[index];
+    const RunControlTab &tab = m_runControlTabs.at(index);
+    QTC_ASSERT(tab.runControl, return);
+    QTC_ASSERT(index != -1 && !tab.runControl->isRunning(), return);
 
     handleOldOutput(tab.window);
     tab.window->scrollToBottom();
@@ -521,7 +521,7 @@ void AppOutputPane::attachToRunControl()
     const int index = currentIndex();
     QTC_ASSERT(index != -1, return);
     RunControl *rc = m_runControlTabs.at(index).runControl;
-    QTC_ASSERT(rc->isRunning(), return);
+    QTC_ASSERT(rc && rc->isRunning(), return);
     ExtensionSystem::Invoker<void>(debuggerPlugin(), "attachExternalApplication", rc);
 }
 
@@ -551,9 +551,10 @@ void AppOutputPane::closeTabs(CloseTabMode mode)
 
 QList<RunControl *> AppOutputPane::allRunControls() const
 {
-    return Utils::transform<QList>(m_runControlTabs,[](const RunControlTab &tab) {
+    const QList<RunControl *> list = Utils::transform<QList>(m_runControlTabs,[](const RunControlTab &tab) {
         return tab.runControl.data();
     });
+    return Utils::filtered(list, [](RunControl *rc) { return rc; });
 }
 
 void AppOutputPane::closeTab(int tabIndex, CloseTabMode closeTabMode)
@@ -568,7 +569,7 @@ void AppOutputPane::closeTab(int tabIndex, CloseTabMode closeTabMode)
     // Prompt user to stop
     if (closeTabMode == CloseTabWithPrompt) {
         QWidget *tabWidget = m_tabWidget->widget(tabIndex);
-        if (runControl->isRunning() && !runControl->promptToStop())
+        if (runControl && runControl->isRunning() && !runControl->promptToStop())
             return;
         // The event loop has run, thus the ordering might have changed, a tab might
         // have been closed, so do some strange things...