From 4558fc1b449496ec26465a580259e0132b913644 Mon Sep 17 00:00:00 2001
From: rnv <rnv@opencascade.com>
Date: Fri, 22 Mar 2019 10:59:36 +0300
Subject: [PATCH] 54519: [TC-9.3.0]: SIGSEGV during exit if dimensions are
 editing

---
 src/MeasureGUI/MeasureGUI_DimensionInteractor.cxx | 14 ++++++++------
 src/MeasureGUI/MeasureGUI_DimensionInteractor.h   |  3 ++-
 src/MeasureGUI/MeasureGUI_ManageDimensionsDlg.cxx |  5 ++++-
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/src/MeasureGUI/MeasureGUI_DimensionInteractor.cxx b/src/MeasureGUI/MeasureGUI_DimensionInteractor.cxx
index a41e49487..0777440a2 100644
--- a/src/MeasureGUI/MeasureGUI_DimensionInteractor.cxx
+++ b/src/MeasureGUI/MeasureGUI_DimensionInteractor.cxx
@@ -132,12 +132,14 @@ void MeasureGUI_DimensionInteractor::Disable()
 
   myIsEnabled = false;
 
-  // remove event filtering from viewer windows
-  QVector<SUIT_ViewWindow*>           aViews  = myVM->getViews();
-  QVector<SUIT_ViewWindow*>::iterator aViewIt = aViews.begin();
-  for ( ; aViewIt != aViews.end(); ++aViewIt )
-  {
-    DisconnectView( *aViewIt );
+  if (myVM) {
+    // remove event filtering from viewer windows
+    QVector<SUIT_ViewWindow*>           aViews  = myVM->getViews();
+    QVector<SUIT_ViewWindow*>::iterator aViewIt = aViews.begin();
+    for ( ; aViewIt != aViews.end(); ++aViewIt )
+    {
+      DisconnectView( *aViewIt );
+    }
   }
 }
 
diff --git a/src/MeasureGUI/MeasureGUI_DimensionInteractor.h b/src/MeasureGUI/MeasureGUI_DimensionInteractor.h
index 9343a9817..cde51bafd 100644
--- a/src/MeasureGUI/MeasureGUI_DimensionInteractor.h
+++ b/src/MeasureGUI/MeasureGUI_DimensionInteractor.h
@@ -29,6 +29,7 @@
 
 #include <GeometryGUI.h>
 #include <QObject>
+#include <QPointer>
 
 #include <SelectMgr_EntityOwner.hxx>
 #include <NCollection_Sequence.hxx>
@@ -165,7 +166,7 @@ private:
 private:
   GeometryGUI*            myGeomGUI;
   bool                    myIsEnabled;
-  OCCViewer_ViewManager*  myVM;
+  QPointer<OCCViewer_ViewManager> myVM;
   OCCViewer_Viewer*       myViewer;
   Operation               myOperation;
   bool                    myOperationStarted;
diff --git a/src/MeasureGUI/MeasureGUI_ManageDimensionsDlg.cxx b/src/MeasureGUI/MeasureGUI_ManageDimensionsDlg.cxx
index de58cbcff..49a3f1478 100644
--- a/src/MeasureGUI/MeasureGUI_ManageDimensionsDlg.cxx
+++ b/src/MeasureGUI/MeasureGUI_ManageDimensionsDlg.cxx
@@ -129,7 +129,7 @@ MeasureGUI_ManageDimensionsDlg::MeasureGUI_ManageDimensionsDlg( GeometryGUI* the
   connect( myGeomGUI, SIGNAL( SignalDeactivateActiveDialog() ), this, SLOT( OnDeactivateThisDialog() ) );
   connect( myGeomGUI, SIGNAL( SignalCloseAllDialogs() ),        this, SLOT( ClickOnCancel() ) );
 
-  myDimensionInteractor = new MeasureGUI_DimensionInteractor( theGUI, theParent ),
+  myDimensionInteractor = new MeasureGUI_DimensionInteractor( theGUI, this ),
 
   SelectionIntoArgument( Selection_Object );
 
@@ -245,6 +245,9 @@ void MeasureGUI_ManageDimensionsDlg::StartSelection( const Selection theSelectio
 //=================================================================================
 void MeasureGUI_ManageDimensionsDlg::StopSelection()
 {
+  if( !myGeomGUI || !myGeomGUI->getApp() || !myGeomGUI->getApp()->selectionMgr() )
+    return;
+
   if ( myCurrentSelection == Selection_Object )
   {
     /* -----------------------------------------------  *