diff --git a/src/App/Document.h b/src/App/Document.h
index ccfe0c9827..8b2e5f3b8c 100644
--- a/src/App/Document.h
+++ b/src/App/Document.h
@@ -60,7 +60,7 @@ namespace App
 /// The document class
 class AppExport Document : public App::PropertyContainer
 {
-    PROPERTY_HEADER(App::Document);
+    PROPERTY_HEADER_WITH_OVERRIDE(App::Document);
 
 public:
     enum Status {
@@ -222,11 +222,11 @@ public:
     const char* getName() const;
     //@}
 
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
     /// returns the complete document memory consumption, including all managed DocObjects and Undo Redo.
-    unsigned int getMemSize (void) const;
+    unsigned int getMemSize (void) const override;
 
     /** @name Object handling  */
     //@{
@@ -478,7 +478,7 @@ public:
     /// Function called to signal that an object identifier has been renamed
     void renameObjectIdentifiers(const std::map<App::ObjectIdentifier, App::ObjectIdentifier> & paths, const std::function<bool(const App::DocumentObject*)> &selector = [](const App::DocumentObject *) { return true; });
 
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
 
     virtual std::string getFullName() const override;
 
@@ -508,8 +508,8 @@ protected:
     void writeObjects(const std::vector<App::DocumentObject*>&, Base::Writer &writer) const;
     bool saveToFile(const char* filename) const;
 
-    void onBeforeChange(const Property* prop);
-    void onChanged(const Property* prop);
+    void onBeforeChange(const Property* prop) override;
+    void onChanged(const Property* prop) override;
     /// callback from the Document objects before property will be changed
     void onBeforeChangeProperty(const TransactionalObject *Who, const Property *What);
     /// callback from the Document objects after property was changed
diff --git a/src/App/DocumentObject.h b/src/App/DocumentObject.h
index e2c7a28336..f2599bb300 100644
--- a/src/App/DocumentObject.h
+++ b/src/App/DocumentObject.h
@@ -90,7 +90,7 @@ public:
  */
 class AppExport DocumentObject: public App::TransactionalObject
 {
-    PROPERTY_HEADER(App::DocumentObject);
+    PROPERTY_HEADER_WITH_OVERRIDE(App::DocumentObject);
 
 public:
 
@@ -126,8 +126,8 @@ public:
     std::string getExportName(bool forced=false) const;
     /// Return the object full name of the form DocName#ObjName
     virtual std::string getFullName() const override;
-    virtual bool isAttachedToDocument() const;
-    virtual const char* detachFromDocument();
+    virtual bool isAttachedToDocument() const override;
+    virtual const char* detachFromDocument() override;
     /// gets the document in which this Object is handled
     App::Document *getDocument(void) const;
 
@@ -303,7 +303,7 @@ public:
      * additional or different behavior.
      */
     virtual void onLostLinkToObject(DocumentObject*);
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
 
     /** Get the sub element/object by name
      *
@@ -405,7 +405,7 @@ public:
 
     static DocumentObjectExecReturn *StdReturn;
 
-    virtual void Save (Base::Writer &writer) const;
+    virtual void Save (Base::Writer &writer) const override;
 
     /* Expression support */
 
@@ -576,9 +576,9 @@ protected:
     void setDocument(App::Document* doc);
 
     /// get called before the value is changed
-    virtual void onBeforeChange(const Property* prop);
+    virtual void onBeforeChange(const Property* prop) override;
     /// get called by the container when a property was changed
-    virtual void onChanged(const Property* prop);
+    virtual void onChanged(const Property* prop) override;
     /// get called after a document has been fully restored
     virtual void onDocumentRestored();
     /// get called after setting the document
diff --git a/src/App/DocumentObjectGroup.h b/src/App/DocumentObjectGroup.h
index 3e1cef8b09..5a74078892 100644
--- a/src/App/DocumentObjectGroup.h
+++ b/src/App/DocumentObjectGroup.h
@@ -44,11 +44,11 @@ public:
     virtual ~DocumentObjectGroup();
     
     /// returns the type name of the ViewProvider
-    virtual const char* getViewProviderName(void) const {
+    virtual const char* getViewProviderName(void) const override{
         return "Gui::ViewProviderDocumentObjectGroup";
     }
     
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
 };
 
 typedef App::FeaturePythonT<DocumentObjectGroup> DocumentObjectGroupPython;
diff --git a/src/App/Expression.cpp b/src/App/Expression.cpp
index 67c919fccc..bf6dc83154 100644
--- a/src/App/Expression.cpp
+++ b/src/App/Expression.cpp
@@ -423,8 +423,8 @@ static Py::Object _pyObjectFromAny(const App::any &value, const Expression *e) {
         return Py::Long(cast<int>(value));
 #endif
     else if (is_type(value,typeid(long))) {
-        long l = cast<long>(value);
 #if PY_MAJOR_VERSION < 3
+        long l = cast<long>(value);
         if(std::abs(l)<=INT_MAX)
             return Py::Int(int(l));
 #endif
@@ -505,7 +505,7 @@ bool pyToQuantity(Quantity &q, const Py::Object &pyobj) {
     return true;
 }
 
-static inline Quantity pyToQuantity(const Py::Object &pyobj, 
+/*static inline Quantity pyToQuantity(const Py::Object &pyobj, 
         const Expression *e, const char *msg=0) 
 {
     Quantity q;
@@ -515,7 +515,7 @@ static inline Quantity pyToQuantity(const Py::Object &pyobj,
         __EXPR_THROW(TypeError,msg,e);
     }
     return q;
-}
+}*/
 
 Py::Object pyFromQuantity(const Quantity &quantity) {
     if(!quantity.getUnit().isEmpty())
diff --git a/src/App/Expression.h b/src/App/Expression.h
index f253292e5d..599bc4ba3f 100644
--- a/src/App/Expression.h
+++ b/src/App/Expression.h
@@ -35,6 +35,12 @@
 #include <deque>
 #include <App/Range.h>
 
+//FIXME: PyObjectExpression hides overloaded virtual functions
+#if defined(__clang__)
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Woverloaded-virtual"
+#endif
+
 namespace App  {
 
 class DocumentObject;
@@ -654,4 +660,9 @@ public:
 }
 
 }
+
+#if defined(__clang__)
+# pragma clang diagnostic pop
+#endif
+
 #endif // EXPRESSION_H
diff --git a/src/App/ExtensionContainer.h b/src/App/ExtensionContainer.h
index 5cb141e36c..9c5c2ae53f 100644
--- a/src/App/ExtensionContainer.h
+++ b/src/App/ExtensionContainer.h
@@ -193,7 +193,7 @@ private:
 };
 
 #define PROPERTY_HEADER_WITH_EXTENSIONS(_class_) \
-  PROPERTY_HEADER(_class)
+  PROPERTY_HEADER_WITH_OVERRIDE(_class)
 
 /// We make sur that the PropertyData of the container is not connected to the one of the extension
 #define PROPERTY_SOURCE_WITH_EXTENSIONS(_class_, _parentclass_) \
diff --git a/src/App/FeaturePython.h b/src/App/FeaturePython.h
index 54e53588bd..8183fb3886 100644
--- a/src/App/FeaturePython.h
+++ b/src/App/FeaturePython.h
@@ -159,7 +159,7 @@ public:
 template <class FeatureT>
 class FeaturePythonT : public FeatureT
 {
-    PROPERTY_HEADER(App::FeaturePythonT<FeatureT>);
+    PROPERTY_HEADER_WITH_OVERRIDE(App::FeaturePythonT<FeatureT>);
 
 public:
     FeaturePythonT() {
@@ -173,7 +173,7 @@ public:
 
     /** @name methods override DocumentObject */
     //@{
-    short mustExecute() const {
+    short mustExecute() const override {
         if (this->isTouched())
             return 1;
         auto ret = FeatureT::mustExecute();
@@ -181,7 +181,7 @@ public:
         return imp->mustExecute()?1:0;
     }
     /// recalculate the Feature
-    virtual DocumentObjectExecReturn *execute(void) {
+    virtual DocumentObjectExecReturn *execute(void) override {
         try {
             bool handled = imp->execute();
             if (!handled)
@@ -199,7 +199,7 @@ public:
         return FeatureT::getViewProviderNameOverride();
     }
     /// returns the type name of the ViewProvider
-    virtual const char* getViewProviderName(void) const {
+    virtual const char* getViewProviderName(void) const override {
         return FeatureT::getViewProviderName();
         //return "Gui::ViewProviderPythonFeature";
     }
@@ -279,14 +279,14 @@ public:
         return FeatureT::canLoadPartial();
     }
 
-    PyObject *getPyObject(void) {
+    PyObject *getPyObject(void) override {
         if (FeatureT::PythonObject.is(Py::_None())) {
             // ref counter is set to 1
             FeatureT::PythonObject = Py::Object(imp->getPyObject(),true);
         }
         return Py::new_reference_to(FeatureT::PythonObject);
     }
-    void setPyObject(PyObject *obj) {
+    void setPyObject(PyObject *obj) override {
         if (obj)
             FeatureT::PythonObject = obj;
         else
@@ -294,7 +294,7 @@ public:
     }
 
 protected:
-    virtual void onBeforeChange(const Property* prop) {
+    virtual void onBeforeChange(const Property* prop) override {
         FeatureT::onBeforeChange(prop);
         imp->onBeforeChange(prop);
     }
@@ -302,13 +302,13 @@ protected:
         if(!imp->onBeforeChangeLabel(newLabel))
             FeatureT::onBeforeChangeLabel(newLabel);
     }
-    virtual void onChanged(const Property* prop) {
+    virtual void onChanged(const Property* prop) override {
         if(prop == &Proxy)
             imp->init(Proxy.getValue().ptr());
         imp->onChanged(prop);
         FeatureT::onChanged(prop);
     }
-    virtual void onDocumentRestored() {
+    virtual void onDocumentRestored() override {
         imp->onDocumentRestored();
         FeatureT::onDocumentRestored();
     }
diff --git a/src/App/Link.h b/src/App/Link.h
index 55c87d3e0c..9961b6d0fd 100644
--- a/src/App/Link.h
+++ b/src/App/Link.h
@@ -50,7 +50,7 @@ namespace App
 
 class AppExport LinkBaseExtension : public App::DocumentObjectExtension 
 {
-    EXTENSION_PROPERTY_HEADER(App::LinkExtension);
+    EXTENSION_PROPERTY_HEADER_WITH_OVERRIDE(App::LinkExtension);
     typedef App::DocumentObjectExtension inherited;
 
 public:
@@ -318,7 +318,7 @@ typedef ExtensionPythonT<LinkBaseExtension> LinkBaseExtensionPython;
 
 class AppExport LinkExtension : public LinkBaseExtension
 {
-    EXTENSION_PROPERTY_HEADER(App::LinkExtension);
+    EXTENSION_PROPERTY_HEADER_WITH_OVERRIDE(App::LinkExtension);
     typedef LinkBaseExtension inherited;
 
 public:
diff --git a/src/App/Part.h b/src/App/Part.h
index 3f4ed3c977..d9d86618f4 100644
--- a/src/App/Part.h
+++ b/src/App/Part.h
@@ -80,7 +80,7 @@ public:
     virtual ~Part();
 
     /// returns the type name of the ViewProvider
-    virtual const char* getViewProviderName(void) const {
+    virtual const char* getViewProviderName(void) const override {
         return "Gui::ViewProviderPart";
     }
 
@@ -91,7 +91,7 @@ public:
      */
     static App::Part* getPartOfObject (const DocumentObject* obj);
 
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
 };
 
 //typedef App::FeaturePythonT<Part> PartPython;
diff --git a/src/App/Property.h b/src/App/Property.h
index 4c45c6397b..c3a7deee83 100644
--- a/src/App/Property.h
+++ b/src/App/Property.h
@@ -57,7 +57,7 @@ class ObjectIdentifier;
  */
 class AppExport Property : public Base::Persistence
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
     enum Status
@@ -110,7 +110,7 @@ public:
      * This method is defined in Base::Persistence
      * @see Base::Persistence
      */
-    virtual unsigned int getMemSize (void) const {
+    virtual unsigned int getMemSize (void) const override {
         // you have to implement this method in all property classes!
         return sizeof(father) + sizeof(StatusBits);
     }
@@ -424,7 +424,7 @@ protected:
 class AppExport PropertyLists : public Property, public PropertyListsBase
 
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 public:
     virtual void setPyObject(PyObject *obj) override {
         _setPyObject(obj);
diff --git a/src/App/PropertyExpressionEngine.h b/src/App/PropertyExpressionEngine.h
index 793de46843..61c6b47b88 100644
--- a/src/App/PropertyExpressionEngine.h
+++ b/src/App/PropertyExpressionEngine.h
@@ -64,7 +64,7 @@ private:
 class AppExport PropertyExpressionEngine : public App::PropertyExpressionContainer, 
                                            private App::AtomicPropertyChangeInterface<PropertyExpressionEngine>
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 public:
 
     virtual void updateElementReference(
@@ -103,7 +103,7 @@ public:
     PropertyExpressionEngine();
     ~PropertyExpressionEngine();
 
-    unsigned int getMemSize (void) const;
+    unsigned int getMemSize (void) const override;
 
     virtual std::map<App::ObjectIdentifier, const App::Expression*> getExpressions() const override;
     virtual void setExpressions(std::map<App::ObjectIdentifier, App::ExpressionPtr> &&exprs) override;
@@ -111,17 +111,17 @@ public:
 
     void setValue() { } // Dummy
 
-    Property *Copy(void) const;
+    Property *Copy(void) const override;
 
-    void Paste(const Property &from);
+    void Paste(const Property &from) override;
 
-    void Save (Base::Writer & writer) const;
+    void Save (Base::Writer & writer) const override;
 
-    void Restore(Base::XMLReader &reader);
+    void Restore(Base::XMLReader &reader) override;
 
     void setValue(const App::ObjectIdentifier &path, boost::shared_ptr<App::Expression> expr);
 
-    const boost::any getPathValue(const App::ObjectIdentifier & path) const;
+    const boost::any getPathValue(const App::ObjectIdentifier & path) const override;
 
     /// Execute options
     enum ExecuteOption {
@@ -153,7 +153,7 @@ public:
 
     void renameObjectIdentifiers(const std::map<App::ObjectIdentifier, App::ObjectIdentifier> & paths);
 
-    App::ObjectIdentifier canonicalPath(const App::ObjectIdentifier &p) const;
+    App::ObjectIdentifier canonicalPath(const App::ObjectIdentifier &p) const override;
 
     size_t numExpressions() const;
 
@@ -164,8 +164,8 @@ public:
     virtual void onContainerRestored() override;
 
     /* Python interface */
-    PyObject *getPyObject(void);
-    void setPyObject(PyObject *);
+    PyObject *getPyObject(void) override;
+    void setPyObject(PyObject *) override;
 
 protected:
     virtual void hasSetValue() override;
diff --git a/src/App/PropertyGeo.h b/src/App/PropertyGeo.h
index c9c262099d..affc4d4078 100644
--- a/src/App/PropertyGeo.h
+++ b/src/App/PropertyGeo.h
@@ -56,7 +56,7 @@ class Placement;
  */
 class AppExport PropertyVector: public Property
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
     /**
@@ -77,25 +77,25 @@ public:
     void setValue(double x, double y, double z);
 
     /// Get valid paths for this property; used by auto completer
-    void getPaths(std::vector<ObjectIdentifier> &paths) const;
+    void getPaths(std::vector<ObjectIdentifier> &paths) const override;
 
     /** This method returns a string representation of the property
      */
     const Base::Vector3d &getValue(void) const;
-    const char* getEditorName(void) const {
+    const char* getEditorName(void) const override {
         return "Gui::PropertyEditor::PropertyVectorItem";
     }
 
-    virtual PyObject *getPyObject(void);
-    virtual void setPyObject(PyObject *);
+    virtual PyObject *getPyObject(void) override;
+    virtual void setPyObject(PyObject *) override;
 
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
 
-    virtual unsigned int getMemSize (void) const {
+    virtual unsigned int getMemSize (void) const override {
         return sizeof(Base::Vector3d);
     }
 
@@ -192,7 +192,7 @@ public:
 
 class AppExport PropertyVectorList: public PropertyListsT<Base::Vector3d>
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
     typedef PropertyListsT<Base::Vector3d> inherited;
 
@@ -212,18 +212,18 @@ public:
     void setValue(double x, double y, double z);
     using inherited::setValue;
 
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
 
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
-    virtual void SaveDocFile (Base::Writer &writer) const;
-    virtual void RestoreDocFile(Base::Reader &reader);
+    virtual void SaveDocFile (Base::Writer &writer) const override;
+    virtual void RestoreDocFile(Base::Reader &reader) override;
 
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
 
-    virtual unsigned int getMemSize (void) const;
+    virtual unsigned int getMemSize (void) const override;
 
 protected:
     Base::Vector3d getPyValue(PyObject *) const override;
@@ -283,7 +283,7 @@ private:
  */
 class AppExport PropertyPlacement: public Property
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
     /**
@@ -315,28 +315,28 @@ public:
     const Base::Placement &getValue(void) const;
 
     /// Get valid paths for this property; used by auto completer
-    void getPaths(std::vector<ObjectIdentifier> &paths) const;
+    void getPaths(std::vector<ObjectIdentifier> &paths) const override;
 
-    void setPathValue(const ObjectIdentifier &path, const boost::any &value);
+    void setPathValue(const ObjectIdentifier &path, const boost::any &value) override;
 
     virtual const boost::any getPathValue(const ObjectIdentifier &path) const override;
 
     virtual bool getPyPathValue(const ObjectIdentifier &path, Py::Object &res) const override;
 
-    const char* getEditorName(void) const {
+    const char* getEditorName(void) const override {
         return "Gui::PropertyEditor::PropertyPlacementItem";
     }
 
-    virtual PyObject *getPyObject(void);
-    virtual void setPyObject(PyObject *);
+    virtual PyObject *getPyObject(void) override;
+    virtual void setPyObject(PyObject *) override;
 
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
 
-    virtual unsigned int getMemSize (void) const {
+    virtual unsigned int getMemSize (void) const override {
         return sizeof(Base::Placement);
     }
 
@@ -377,7 +377,7 @@ public:
 
 class AppExport PropertyPlacementList: public PropertyListsT<Base::Placement>
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
     /**
@@ -387,18 +387,18 @@ public:
 
     virtual ~PropertyPlacementList();
 
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
 
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
-    virtual void SaveDocFile (Base::Writer &writer) const;
-    virtual void RestoreDocFile(Base::Reader &reader);
+    virtual void SaveDocFile (Base::Writer &writer) const override;
+    virtual void RestoreDocFile(Base::Reader &reader) override;
 
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
 
-    virtual unsigned int getMemSize (void) const;
+    virtual unsigned int getMemSize (void) const override;
 
 protected:
     Base::Placement getPyValue(PyObject *) const override;
diff --git a/src/App/PropertyLinks.h b/src/App/PropertyLinks.h
index 5f5a1586fa..df3a50730c 100644
--- a/src/App/PropertyLinks.h
+++ b/src/App/PropertyLinks.h
@@ -102,7 +102,7 @@ protected:
 /// Parent class of all link type properties
 class AppExport PropertyLinkBase : public Property, public ScopedLink
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 public:
     typedef std::pair<std::string,std::string> ShadowSub;
 
@@ -571,7 +571,7 @@ private:
  */
 class AppExport PropertyLink : public PropertyLinkBase
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
     /**
@@ -607,19 +607,19 @@ public:
         return _pcLink ? dynamic_cast<_type>(_pcLink) : 0;
     }
 
-    virtual PyObject *getPyObject(void);
-    virtual void setPyObject(PyObject *);
+    virtual PyObject *getPyObject(void) override;
+    virtual void setPyObject(PyObject *) override;
 
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
 
-    virtual unsigned int getMemSize (void) const{
+    virtual unsigned int getMemSize (void) const override {
         return sizeof(App::DocumentObject *);
     }
-    virtual const char* getEditorName(void) const
+    virtual const char* getEditorName(void) const override
     { return "Gui::PropertyEditor::PropertyLinkItem"; }
 
     virtual void getLinks(std::vector<App::DocumentObject *> &objs, 
@@ -665,7 +665,7 @@ public:
 
 class AppExport PropertyLinkListBase: public PropertyLinkBase, public PropertyListsBase
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 public:
     virtual void setPyObject(PyObject *obj) override {
         _setPyObject(obj);
@@ -675,7 +675,7 @@ public:
 class AppExport PropertyLinkList : 
     public PropertyListsT<DocumentObject*,std::vector<DocumentObject*>, PropertyLinkListBase>
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
     typedef PropertyListsT<DocumentObject*,std::vector<DocumentObject*>,PropertyLinkListBase> inherited;
 
 public:
@@ -691,8 +691,8 @@ public:
      */
     virtual ~PropertyLinkList();
 
-    virtual void setSize(int newSize);
-    virtual void setSize(int newSize, const_reference def);
+    virtual void setSize(int newSize) override;
+    virtual void setSize(int newSize, const_reference def) override;
 
     /** Sets the property
     */
@@ -700,16 +700,16 @@ public:
 
     void set1Value(int idx, DocumentObject * const &value) override;
 
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
 
-    virtual void Save(Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save(Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
 
-    virtual unsigned int getMemSize(void) const;
-    virtual const char* getEditorName(void) const
+    virtual unsigned int getMemSize(void) const override;
+    virtual const char* getEditorName(void) const override
     { return "Gui::PropertyEditor::PropertyLinkListItem"; }
 
     virtual void getLinks(std::vector<App::DocumentObject *> &objs, 
@@ -772,7 +772,7 @@ class PropertyXLinkSub;
  */
 class AppExport PropertyLinkSub : public PropertyLinkBase
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
     /**
@@ -825,14 +825,14 @@ public:
         return _pcLinkSub ? dynamic_cast<_type>(_pcLinkSub) : 0;
     }
 
-    virtual PyObject *getPyObject(void);
-    virtual void setPyObject(PyObject *);
+    virtual PyObject *getPyObject(void) override;
+    virtual void setPyObject(PyObject *) override;
 
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
 
     /// Return a copy of the property if any changes caused by importing external object 
     virtual Property *CopyOnImportExternal(const std::map<std::string,std::string> &nameMap) const override;
@@ -843,7 +843,7 @@ public:
     virtual Property *CopyOnLinkReplace(const App::DocumentObject *parent,
             App::DocumentObject *oldObj, App::DocumentObject *newObj) const override;
 
-    virtual unsigned int getMemSize (void) const{
+    virtual unsigned int getMemSize (void) const override {
         return sizeof(App::DocumentObject *);
     }
 
@@ -896,7 +896,7 @@ public:
 
 class AppExport PropertyLinkSubList : public PropertyLinkBase
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
     typedef std::pair<DocumentObject*, std::vector<std::string> > SubSet;
@@ -967,14 +967,14 @@ public:
     void setSubListValues(const std::vector<SubSet>&);
     std::vector<SubSet> getSubListValues(bool newStyle=false) const;
 
-    virtual PyObject *getPyObject(void);
-    virtual void setPyObject(PyObject *);
+    virtual PyObject *getPyObject(void) override;
+    virtual void setPyObject(PyObject *) override;
 
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
 
     /// Return a copy of the property if any changes caused by importing external object 
     virtual Property *CopyOnImportExternal(const std::map<std::string,std::string> &nameMap) const override;
@@ -985,7 +985,7 @@ public:
     virtual Property *CopyOnLinkReplace(const App::DocumentObject *parent,
             App::DocumentObject *oldObj, App::DocumentObject *newObj) const override;
 
-    virtual unsigned int getMemSize (void) const;
+    virtual unsigned int getMemSize (void) const override;
 
     virtual void updateElementReference(
             DocumentObject *feature,bool reverse=false, bool notify=false) override;
@@ -1005,7 +1005,6 @@ private:
     std::vector<std::string>     _lSubList;
     std::vector<ShadowSub> _ShadowSubList;
     std::vector<int> _mapped;
-    bool _restoreLabel;
 };
 
 /** The general Link Property with Child scope
@@ -1041,7 +1040,7 @@ class PropertyXLinkSubList;
  */
 class AppExport PropertyXLink : public PropertyLinkGlobal
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
     PropertyXLink(bool allowPartial=false, PropertyLinkBase *parent=0);
@@ -1067,11 +1066,11 @@ public:
 
     virtual int checkRestore(std::string *msg=0) const override;
 
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
 
     /// Return a copy of the property if any changes caused by importing external object 
     virtual Property *CopyOnImportExternal(const std::map<std::string,std::string> &nameMap) const override;
@@ -1082,8 +1081,8 @@ public:
     virtual Property *CopyOnLinkReplace(const App::DocumentObject *parent,
             App::DocumentObject *oldObj, App::DocumentObject *newObj) const override;
 
-    virtual PyObject *getPyObject(void);
-    virtual void setPyObject(PyObject *);
+    virtual PyObject *getPyObject(void) override;
+    virtual void setPyObject(PyObject *) override;
 
     friend class DocInfo;
 
@@ -1159,10 +1158,16 @@ protected:
 };
 
 
+//FIXME: PropertyXLinkSub hides overloaded virtual functions
+#if defined(__clang__)
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Woverloaded-virtual"
+#endif
+
 /** Link to one or more (sub)object from the same or different document
  */
 class AppExport PropertyXLinkSub: public PropertyXLink {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
     PropertyXLinkSub(bool allowPartial=false, PropertyLinkBase *parent=0);
@@ -1180,18 +1185,22 @@ public:
 
     virtual bool upgrade(Base::XMLReader &reader, const char *typeName) override;
 
-    virtual PyObject *getPyObject(void);
-    virtual void setPyObject(PyObject *);
+    virtual PyObject *getPyObject(void) override;
+    virtual void setPyObject(PyObject *) override;
 
 protected:
-    virtual PropertyXLink *createInstance() const;
+    virtual PropertyXLink *createInstance() const override;
 };
 
+#if defined(__clang__)
+# pragma clang diagnostic pop
+#endif
+
 
 /** Link to one or more (sub)object(s) of one or more object(s) from the same or different document
  */
 class AppExport PropertyXLinkSubList: public PropertyLinkBase {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
     PropertyXLinkSubList();
@@ -1244,14 +1253,14 @@ public:
         return _Links;
     }
 
-    virtual PyObject *getPyObject(void);
-    virtual void setPyObject(PyObject *);
+    virtual PyObject *getPyObject(void) override;
+    virtual void setPyObject(PyObject *) override;
 
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
 
     virtual Property *CopyOnImportExternal(const std::map<std::string,std::string> &nameMap) const override;
 
@@ -1261,7 +1270,7 @@ public:
     virtual Property *CopyOnLinkReplace(const App::DocumentObject *parent,
             App::DocumentObject *oldObj, App::DocumentObject *newObj) const override;
 
-    virtual unsigned int getMemSize (void) const;
+    virtual unsigned int getMemSize (void) const override;
 
     virtual void updateElementReference(
             DocumentObject *feature,bool reverse=false, bool notify=false) override;
@@ -1293,7 +1302,7 @@ protected:
  * @sa See PropertyExpressionEngine for example usage
  */
 class AppExport PropertyXLinkContainer : public PropertyLinkBase {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 public:
     PropertyXLinkContainer();
     ~PropertyXLinkContainer();
diff --git a/src/App/PropertyStandard.h b/src/App/PropertyStandard.h
index b8eaf1798d..76a452f8e2 100644
--- a/src/App/PropertyStandard.h
+++ b/src/App/PropertyStandard.h
@@ -303,7 +303,7 @@ public:
  */
 class AppExport PropertyIntegerList: public PropertyListsT<long>
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
     /**
@@ -319,17 +319,17 @@ public:
      */
     virtual ~PropertyIntegerList();
 
-    virtual const char* getEditorName(void) const
+    virtual const char* getEditorName(void) const override
     { return "Gui::PropertyEditor::PropertyIntegerListItem"; }
 
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
     
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
     
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
-    virtual unsigned int getMemSize (void) const;
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
+    virtual unsigned int getMemSize (void) const override;
 
 protected:
     long getPyValue(PyObject *item) const override;
@@ -582,7 +582,7 @@ public:
 
 class AppExport PropertyFloatList: public PropertyListsT<double>
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
 
@@ -598,20 +598,20 @@ public:
      */
     virtual ~PropertyFloatList();
     
-    virtual const char* getEditorName(void) const
+    virtual const char* getEditorName(void) const override
     { return "Gui::PropertyEditor::PropertyFloatListItem"; }
 
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
     
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
     
-    virtual void SaveDocFile (Base::Writer &writer) const;
-    virtual void RestoreDocFile(Base::Reader &reader);
+    virtual void SaveDocFile (Base::Writer &writer) const override;
+    virtual void RestoreDocFile(Base::Reader &reader) override;
     
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
-    virtual unsigned int getMemSize (void) const;
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
+    virtual unsigned int getMemSize (void) const override;
 
 protected:
     double getPyValue(PyObject *item) const override;
@@ -723,7 +723,7 @@ public:
 
 class AppExport PropertyStringList: public PropertyListsT<std::string>
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
     typedef PropertyListsT<std::string> inherited;
 
 public:
@@ -743,18 +743,18 @@ public:
     void setValues(const std::list<std::string>&);
     using inherited::setValues;
     
-    virtual const char* getEditorName(void) const
+    virtual const char* getEditorName(void) const override
     { return "Gui::PropertyEditor::PropertyStringListItem"; }
     
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
     
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
     
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
     
-    virtual unsigned int getMemSize (void) const;
+    virtual unsigned int getMemSize (void) const override;
     
 protected:
     std::string getPyValue(PyObject *item) const override;
@@ -809,22 +809,22 @@ private:
  */
 class AppExport PropertyBoolList : public PropertyListsT<bool,boost::dynamic_bitset<> >
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
     typedef PropertyListsT<bool,boost::dynamic_bitset<> > inherited;
 
 public:
     PropertyBoolList();
     virtual ~PropertyBoolList();
 
-    virtual PyObject *getPyObject(void);
-    virtual void setPyObject(PyObject *);
+    virtual PyObject *getPyObject(void) override;
+    virtual void setPyObject(PyObject *) override;
     
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
     
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
-    virtual unsigned int getMemSize (void) const;
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
+    virtual unsigned int getMemSize (void) const override;
 
 protected:
     bool getPyValue(PyObject *) const override;
@@ -881,7 +881,7 @@ private:
 
 class AppExport PropertyColorList: public PropertyListsT<Color>
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
        
@@ -897,17 +897,17 @@ public:
      */
     virtual ~PropertyColorList();
 
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
     
-    virtual void Save (Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save (Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
     
-    virtual void SaveDocFile (Base::Writer &writer) const;
-    virtual void RestoreDocFile(Base::Reader &reader);
+    virtual void SaveDocFile (Base::Writer &writer) const override;
+    virtual void RestoreDocFile(Base::Reader &reader) override;
     
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
-    virtual unsigned int getMemSize (void) const;
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
+    virtual unsigned int getMemSize (void) const override;
 
 protected:
     Color getPyValue(PyObject *) const override;
@@ -969,7 +969,7 @@ private:
 */
 class AppExport PropertyMaterialList : public PropertyListsT<Material>
 {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
 
 public:
 
@@ -985,19 +985,19 @@ public:
     */
     virtual ~PropertyMaterialList();
 
-    virtual PyObject *getPyObject(void);
+    virtual PyObject *getPyObject(void) override;
 
-    virtual void Save(Base::Writer &writer) const;
-    virtual void Restore(Base::XMLReader &reader);
+    virtual void Save(Base::Writer &writer) const override;
+    virtual void Restore(Base::XMLReader &reader) override;
 
-    virtual void SaveDocFile(Base::Writer &writer) const;
-    virtual void RestoreDocFile(Base::Reader &reader);
+    virtual void SaveDocFile(Base::Writer &writer) const override;
+    virtual void RestoreDocFile(Base::Reader &reader) override;
 
-    virtual const char* getEditorName(void) const;
+    virtual const char* getEditorName(void) const override;
 
-    virtual Property *Copy(void) const;
-    virtual void Paste(const Property &from);
-    virtual unsigned int getMemSize(void) const;
+    virtual Property *Copy(void) const override;
+    virtual void Paste(const Property &from) override;
+    virtual unsigned int getMemSize(void) const override;
 
 protected:
     Material getPyValue(PyObject *) const override;
@@ -1010,7 +1010,7 @@ protected:
  * object, and then read back as the Python binding of the newly created object.
  */
 class AppExport PropertyPersistentObject: public PropertyString {
-    TYPESYSTEM_HEADER();
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();
     typedef PropertyString inherited;
 public:
     virtual PyObject *getPyObject(void) override;