Fix some minor memory leaks

src/app/qgisapp.cpp

@@ -675,10 +675,9 @@ QgisApp::QgisApp( QSplashScreen *splash, bool restorePlugins, bool skipVersionCh
   mLayerTreeView->setObjectName( "theLayerTreeView" ); // "theLayerTreeView" used to find this canonical instance later
 
   // create undo widget
-  mUndoWidget = new QgsUndoWidget( nullptr, mMapCanvas );
+  mUndoDock = new QDockWidget( tr( "Undo/Redo Panel" ), this );
+  mUndoWidget = new QgsUndoWidget( mUndoDock, mMapCanvas );
   mUndoWidget->setObjectName( "Undo" );
-
-  mUndoDock = new QDockWidget( tr( "Undo/Redo Panel" ), nullptr );
   mUndoDock->setWidget( mUndoWidget );
 
   // Advanced Digitizing dock

src/gui/qgsadvanceddigitizingdockwidget.cpp

@@ -103,10 +103,10 @@ QgsAdvancedDigitizingDockWidget::QgsAdvancedDigitizingDockWidget( QgsMapCanvas*
 
   mCadPaintItem = new QgsAdvancedDigitizingCanvasItem( canvas, this ) ;
 
-  mAngleConstraint = new CadConstraint( mAngleLineEdit, mLockAngleButton, mRelativeAngleButton, mRepeatingLockAngleButton );
-  mDistanceConstraint = new CadConstraint( mDistanceLineEdit, mLockDistanceButton, nullptr, mRepeatingLockDistanceButton ) ;
-  mXConstraint = new CadConstraint( mXLineEdit, mLockXButton, mRelativeXButton, mRepeatingLockXButton );
-  mYConstraint = new CadConstraint( mYLineEdit, mLockYButton, mRelativeYButton, mRepeatingLockYButton ) ;
+  mAngleConstraint.reset( new CadConstraint( mAngleLineEdit, mLockAngleButton, mRelativeAngleButton, mRepeatingLockAngleButton ) );
+  mDistanceConstraint.reset( new CadConstraint( mDistanceLineEdit, mLockDistanceButton, nullptr, mRepeatingLockDistanceButton ) );
+  mXConstraint.reset( new CadConstraint( mXLineEdit, mLockXButton, mRelativeXButton, mRepeatingLockXButton ) );
+  mYConstraint.reset( new CadConstraint( mYLineEdit, mLockYButton, mRelativeYButton, mRepeatingLockYButton ) );
   mAdditionalConstraint = NoConstraint ;
 
   mMapCanvas->installEventFilter( this );
@@ -347,19 +347,19 @@ QgsAdvancedDigitizingDockWidget::CadConstraint* QgsAdvancedDigitizingDockWidget:
   CadConstraint* constraint = nullptr;
   if ( obj == mAngleLineEdit || obj == mLockAngleButton )
   {
-    constraint = mAngleConstraint;
+    constraint = mAngleConstraint.data();
   }
   else if ( obj == mDistanceLineEdit || obj == mLockDistanceButton )
   {
-    constraint = mDistanceConstraint;
+    constraint = mDistanceConstraint.data();
   }
   else if ( obj == mXLineEdit  || obj == mLockXButton )
   {
-    constraint = mXConstraint;
+    constraint = mXConstraint.data();
   }
   else if ( obj == mYLineEdit  || obj == mLockYButton )
   {
-    constraint = mYConstraint;
+    constraint = mYConstraint.data();
   }
   return constraint;
 }
@@ -439,7 +439,7 @@ void QgsAdvancedDigitizingDockWidget::lockConstraint( bool activate /* default t
   if ( activate )
   {
     // deactivate perpendicular/parallel if angle has been activated
-    if ( constraint == mAngleConstraint )
+    if ( constraint == mAngleConstraint.data() )
     {
       lockAdditionalConstraint( NoConstraint );
     }

src/gui/qgsadvanceddigitizingdockwidget.h

@@ -256,13 +256,13 @@ class GUI_EXPORT QgsAdvancedDigitizingDockWidget : public QDockWidget, private U
     //! Additional constraints are used to place perpendicular/parallel segments to snapped segments on the canvas
     AdditionalConstraint additionalConstraint() const  { return mAdditionalConstraint; }
     //! Constraint on the angle
-    const CadConstraint* constraintAngle() const  { return mAngleConstraint; }
+    const CadConstraint* constraintAngle() const  { return mAngleConstraint.data(); }
     //! Constraint on the distance
-    const CadConstraint* constraintDistance() const { return mDistanceConstraint; }
+    const CadConstraint* constraintDistance() const { return mDistanceConstraint.data(); }
     //! Constraint on the X coordinate
-    const CadConstraint* constraintX() const { return mXConstraint; }
+    const CadConstraint* constraintX() const { return mXConstraint.data(); }
     //! Constraint on the Y coordinate
-    const CadConstraint* constraintY() const { return mYConstraint; }
+    const CadConstraint* constraintY() const { return mYConstraint.data(); }
     //! Constraint on a common angle
     bool commonAngleConstraint() const { return mCommonAngleConstraint; }
 
@@ -439,10 +439,10 @@ class GUI_EXPORT QgsAdvancedDigitizingDockWidget : public QDockWidget, private U
     QgsMapMouseEvent::SnappingMode mSnappingMode;
 
     // constraints
-    CadConstraint* mAngleConstraint;
-    CadConstraint* mDistanceConstraint;
-    CadConstraint* mXConstraint;
-    CadConstraint* mYConstraint;
+    QScopedPointer< CadConstraint > mAngleConstraint;
+    QScopedPointer< CadConstraint > mDistanceConstraint;
+    QScopedPointer< CadConstraint > mXConstraint;
+    QScopedPointer< CadConstraint > mYConstraint;
     AdditionalConstraint mAdditionalConstraint;
     int mCommonAngleConstraint; // if 0: do not snap to common angles