fix coverity warnings

src/app/qgslabelpropertydialog.cpp

@@ -199,7 +199,7 @@ void QgsLabelPropertyDialog::blockElementSignals( bool block )
   mRotationSpinBox->blockSignals( block );
 }
 
-void QgsLabelPropertyDialog::setDataDefinedValues( QgsPalLayerSettings layerSettings, QgsVectorLayer* vlayer )
+void QgsLabelPropertyDialog::setDataDefinedValues( const QgsPalLayerSettings &layerSettings, QgsVectorLayer* vlayer )
 {
   //loop through data defined properties and set all the GUI widget values. We can do this
   //even if the data defined property is set to an expression, as it's useful to show

src/app/qgslabelpropertydialog.h

@@ -73,7 +73,7 @@ class APP_EXPORT QgsLabelPropertyDialog: public QDialog, private Ui::QgsLabelPro
     /**Block / unblock all input element signals*/
     void blockElementSignals( bool block );
 
-    void setDataDefinedValues( QgsPalLayerSettings layerSettings, QgsVectorLayer* vlayer );
+    void setDataDefinedValues( const QgsPalLayerSettings &layerSettings, QgsVectorLayer* vlayer );
     void enableDataDefinedWidgets( QgsVectorLayer* vlayer );
 
     /** Updates font when family or style is updated */

src/plugins/grass/qgsgrassnewmapset.cpp

@@ -1263,7 +1263,7 @@ void QgsGrassNewMapset::createMapset()
 
     // TODO: add QgsGrass::setLocation or G_make_location with
     //       database path
-    QgsGrass::activeMode(); // because it calls private QgsGrass::init()
+    ( void )QgsGrass::activeMode(); // because it calls private QgsGrass::init()
 
 #if defined(WIN32)
     G__setenv(( char * ) "GISDBASE", QgsGrass::shortPath( mDatabaseLineEdit->text() ).toUtf8().data() );