Coverity issues:

129097
129098
129099
129101
129102
129132
129134
129203

src/Gui/CommandView.cpp

@@ -812,13 +812,13 @@ void StdCmdToggleSelectability::activated(int iMsg)
  
         for (std::vector<App::DocumentObject*>::const_iterator ft=sel.begin();ft!=sel.end();++ft) {
             ViewProvider *pr = pcDoc->getViewProviderByName((*ft)->getNameInDocument());
-            if(pr->isDerivedFrom(ViewProviderGeometryObject::getClassTypeId())){
-                    if (dynamic_cast<ViewProviderGeometryObject*>(pr)->Selectable.getValue())
-                        doCommand(Gui,"Gui.getDocument(\"%s\").getObject(\"%s\").Selectable=False"
-                                     , (*it)->getName(), (*ft)->getNameInDocument());
-                    else
-                        doCommand(Gui,"Gui.getDocument(\"%s\").getObject(\"%s\").Selectable=True"
-                                     , (*it)->getName(), (*ft)->getNameInDocument());
+            if (pr->isDerivedFrom(ViewProviderGeometryObject::getClassTypeId())){
+                if (static_cast<ViewProviderGeometryObject*>(pr)->Selectable.getValue())
+                    doCommand(Gui,"Gui.getDocument(\"%s\").getObject(\"%s\").Selectable=False"
+                                 , (*it)->getName(), (*ft)->getNameInDocument());
+                else
+                    doCommand(Gui,"Gui.getDocument(\"%s\").getObject(\"%s\").Selectable=True"
+                                 , (*it)->getName(), (*ft)->getNameInDocument());
             }
         }
     }

src/Gui/DlgActionsImp.cpp

@@ -306,6 +306,8 @@ void DlgCustomActionsImp::on_buttonReplaceAction_clicked()
     CommandManager& rclMan = Application::Instance->commandManager();
     Command* pCmd = rclMan.getCommandByName(actionName.constData());
     MacroCommand* macro = dynamic_cast<MacroCommand*>(pCmd);
+    if (!macro)
+        return;
 
     if (!actionWhatsThis->text().isEmpty())
         macro->setWhatsThis(actionWhatsThis->text().toUtf8());

src/Gui/Document.cpp

@@ -219,8 +219,13 @@ bool Document::setEdit(Gui::ViewProvider* p, int ModNum)
 {
     if (d->_editViewProvider)
         resetEdit();
+
     // is it really a ViewProvider of this document?
-    if (d->_ViewProviderMap.find(dynamic_cast<ViewProviderDocumentObject*>(p)->getObject()) == d->_ViewProviderMap.end())
+    ViewProviderDocumentObject* vp = dynamic_cast<ViewProviderDocumentObject*>(p);
+    if (!vp)
+        return false;
+
+    if (d->_ViewProviderMap.find(vp->getObject()) == d->_ViewProviderMap.end())
         return false;
 
     View3DInventor *activeView = dynamic_cast<View3DInventor *>(getActiveView());
@@ -1044,7 +1049,7 @@ void Document::createView(const Base::Type& typeId)
         View3DInventor* firstView = 0;
         QGLWidget* shareWidget = 0;
         if (!theViews.empty()) {
-            firstView = dynamic_cast<View3DInventor*>(theViews.front());
+            firstView = static_cast<View3DInventor*>(theViews.front());
             shareWidget = qobject_cast<QGLWidget*>(firstView->getViewer()->getGLWidget());
         }
 

src/Gui/GuiApplication.cpp

@@ -70,7 +70,7 @@ GUIApplication::~GUIApplication()
 
 bool GUIApplication::notify (QObject * receiver, QEvent * event)
 {
-    if (!receiver && event) {
+    if (!receiver) {
         Base::Console().Log("GUIApplication::notify: Unexpected null receiver, event type: %d\n",
             (int)event->type());
     }

src/Gui/View3DInventorViewer.cpp

@@ -841,7 +841,8 @@ void View3DInventorViewer::setNavigationType(Base::Type t)
 
     NavigationStyle* ns = static_cast<NavigationStyle*>(base);
     ns->operator = (*this->navigation);
-    delete this->navigation;
+    if (this->navigation)
+        ns->operator = (*this->navigation);
     this->navigation = ns;
     this->navigation->setViewer(this);
 }

src/Gui/WidgetFactory.cpp

@@ -390,8 +390,11 @@ QWidget* WidgetFactoryInst::createPrefWidget(const char* sName, QWidget* parent,
     w->setParent(parent);
 
     try {
-        dynamic_cast<PrefWidget*>(w)->setEntryName(sPref);
-        dynamic_cast<PrefWidget*>(w)->restorePreferences();
+        PrefWidget* pw = dynamic_cast<PrefWidget*>(w);
+        if (pw) {
+            pw->setEntryName(sPref);
+            pw->restorePreferences();
+        }
     }
     catch (...) {
 #ifdef FC_DEBUG