diff --git a/src/3rdParty/salomesmesh/src/Controls/SMESH_Controls.cpp b/src/3rdParty/salomesmesh/src/Controls/SMESH_Controls.cpp
index 1192c0ad09..6decc0733a 100644
--- a/src/3rdParty/salomesmesh/src/Controls/SMESH_Controls.cpp
+++ b/src/3rdParty/salomesmesh/src/Controls/SMESH_Controls.cpp
@@ -20,6 +20,12 @@
 // See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
 //
 
+#if defined(__clang__)
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wdelete-non-virtual-dtor"
+# pragma clang diagnostic ignored "-Winconsistent-missing-override"
+#endif
+
 #include "SMESH_ControlsDef.hxx"
 
 #include "SMDS_BallElement.hxx"
@@ -4765,3 +4771,7 @@ bool TMeshModifTracer::IsMeshModified()
   }
   return modified;
 }
+
+#if defined(__clang__)
+# pragma clang diagnostic pop
+#endif
diff --git a/src/3rdParty/salomesmesh/src/SMDS/SMDS_Mesh.cpp b/src/3rdParty/salomesmesh/src/SMDS/SMDS_Mesh.cpp
index 4ac6fd7687..61c8e751d9 100644
--- a/src/3rdParty/salomesmesh/src/SMDS/SMDS_Mesh.cpp
+++ b/src/3rdParty/salomesmesh/src/SMDS/SMDS_Mesh.cpp
@@ -26,6 +26,11 @@
 #pragma warning(disable:4786)
 #endif
 
+#if defined(__clang__)
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Winconsistent-missing-override"
+#endif
+
 #include "SMDS_FaceOfEdges.hxx"
 #include "SMDS_FaceOfNodes.hxx"
 #include "SMDS_Mesh.hxx"
@@ -4851,3 +4856,7 @@ bool SMDS_Mesh::isCompacted()
     }
   return true;
 }
+
+#if defined(__clang__)
+# pragma clang diagnostic pop
+#endif
diff --git a/src/3rdParty/salomesmesh/src/SMESH/SMESH_MeshEditor.cpp b/src/3rdParty/salomesmesh/src/SMESH/SMESH_MeshEditor.cpp
index a742702ff0..4386473fcb 100644
--- a/src/3rdParty/salomesmesh/src/SMESH/SMESH_MeshEditor.cpp
+++ b/src/3rdParty/salomesmesh/src/SMESH/SMESH_MeshEditor.cpp
@@ -24,6 +24,11 @@
 // Created   : Mon Apr 12 16:10:22 2004
 // Author    : Edward AGAPOV (eap)
 
+#if defined(__clang__)
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wdelete-non-virtual-dtor"
+#endif
+
 #include "SMESH_MeshEditor.hxx"
 
 #include "SMDS_FaceOfNodes.hxx"
@@ -12868,3 +12873,7 @@ void SMESH_MeshEditor::copyPosition( const SMDS_MeshNode* from,
   default:;
   }
 }
+
+#if defined(__clang__)
+# pragma clang diagnostic pop
+#endif
diff --git a/src/App/Expression.cpp b/src/App/Expression.cpp
index bbbd2bd4a6..cfddd7e643 100644
--- a/src/App/Expression.cpp
+++ b/src/App/Expression.cpp
@@ -25,6 +25,11 @@
 # include <unistd.h>
 #endif
 
+#if defined(__clang__)
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wdelete-non-virtual-dtor"
+#endif
+
 #include "Base/Exception.h"
 #include <Base/Interpreter.h>
 #include <App/Application.h>
@@ -1988,3 +1993,7 @@ bool ExpressionParser::isTokenAUnit(const std::string & str)
     else
         return false;
 }
+
+#if defined(__clang__)
+# pragma clang diagnostic pop
+#endif
diff --git a/src/Mod/Fem/App/CMakeLists.txt b/src/Mod/Fem/App/CMakeLists.txt
index c84623cf42..e1dc025063 100644
--- a/src/Mod/Fem/App/CMakeLists.txt
+++ b/src/Mod/Fem/App/CMakeLists.txt
@@ -1,4 +1,9 @@
 
+# Many warnings caused by vtk
+if(CMAKE_COMPILER_IS_CLANGXX)
+    set(CMAKE_CXX_FLAGS " ${CMAKE_CXX_FLAGS} -Wno-inconsistent-missing-override")
+endif()
+
 if(MSVC)
     add_definitions(-DFCAppFem -DHAVE_ACOSH -DHAVE_ASINH -DHAVE_ATANH)
 else(MSVC)
diff --git a/src/Mod/Fem/Gui/CMakeLists.txt b/src/Mod/Fem/Gui/CMakeLists.txt
index 722b5b287c..9532cb54ad 100755
--- a/src/Mod/Fem/Gui/CMakeLists.txt
+++ b/src/Mod/Fem/Gui/CMakeLists.txt
@@ -1,3 +1,9 @@
+
+# Many warnings caused by vtk
+if(CMAKE_COMPILER_IS_CLANGXX)
+    set(CMAKE_CXX_FLAGS " ${CMAKE_CXX_FLAGS} -Wno-inconsistent-missing-override")
+endif()
+
 if(MSVC)
     add_definitions(-DFCGuiFem -DHAVE_ACOSH -DHAVE_ASINH -DHAVE_ATANH)
 else(MSVC)
diff --git a/src/Mod/Mesh/App/Core/Smoothing.cpp b/src/Mod/Mesh/App/Core/Smoothing.cpp
index ac3c778134..55f6b58019 100644
--- a/src/Mod/Mesh/App/Core/Smoothing.cpp
+++ b/src/Mod/Mesh/App/Core/Smoothing.cpp
@@ -281,7 +281,6 @@ TaubinSmoothing::~TaubinSmoothing()
 
 void TaubinSmoothing::Smooth(unsigned int iterations)
 {
-    MeshCore::MeshPointArray::_TConstIterator v_it;
     MeshCore::MeshRefPointToPoints vv_it(kernel);
     MeshCore::MeshRefPointToFacets vf_it(kernel);
 
@@ -295,7 +294,6 @@ void TaubinSmoothing::Smooth(unsigned int iterations)
 
 void TaubinSmoothing::SmoothPoints(unsigned int iterations, const std::vector<unsigned long>& point_indices)
 {
-    MeshCore::MeshPointArray::_TConstIterator v_it;
     MeshCore::MeshRefPointToPoints vv_it(kernel);
     MeshCore::MeshRefPointToFacets vf_it(kernel);
 
diff --git a/src/Mod/PartDesign/Gui/ViewProvider.h b/src/Mod/PartDesign/Gui/ViewProvider.h
index 7e930b7ee6..bd01da596a 100644
--- a/src/Mod/PartDesign/Gui/ViewProvider.h
+++ b/src/Mod/PartDesign/Gui/ViewProvider.h
@@ -40,7 +40,7 @@ class TaskDlgFeatureParameters;
 class PartDesignGuiExport ViewProvider : public PartGui::ViewProviderPart, PartGui::ViewProviderAttachExtension
 {
     typedef PartGui::ViewProviderPart inherited;
-    PROPERTY_HEADER_WITH_EXTENSIONS(PartDesignGui::ViewProvider);
+    PROPERTY_HEADER_WITH_OVERRIDE(PartDesignGui::ViewProvider);
 
 public:
     /// constructor
@@ -48,9 +48,9 @@ public:
     /// destructor
     virtual ~ViewProvider();
 
-    virtual bool doubleClicked(void);
-    void updateData(const App::Property*);
-    void onChanged(const App::Property* prop);
+    virtual bool doubleClicked(void) override;
+    void updateData(const App::Property*) override;
+    void onChanged(const App::Property* prop) override;
 
     void setTipIcon(bool onoff);
 
@@ -68,14 +68,14 @@ public:
     //Returns the ViewProvider of the body the feature belongs to, or NULL, if not in a body
     ViewProviderBody* getBodyViewProvider();
 
-    virtual PyObject* getPyObject(void);
+    virtual PyObject* getPyObject(void) override;
 
 protected:
-    virtual void setupContextMenu(QMenu* menu, QObject* receiver, const char* member);
-    virtual bool setEdit(int ModNum);
-    virtual void unsetEdit(int ModNum);
+    virtual void setupContextMenu(QMenu* menu, QObject* receiver, const char* member) override;
+    virtual bool setEdit(int ModNum) override;
+    virtual void unsetEdit(int ModNum) override;
 
-    virtual bool onDelete(const std::vector<std::string> &);
+    virtual bool onDelete(const std::vector<std::string> &) override;
 
     virtual QIcon mergeOverlayIcons (const QIcon & orig) const override;
 
diff --git a/src/Mod/Path/App/Area.cpp b/src/Mod/Path/App/Area.cpp
index 5649e05bcc..543d31c671 100644
--- a/src/Mod/Path/App/Area.cpp
+++ b/src/Mod/Path/App/Area.cpp
@@ -2970,7 +2970,7 @@ std::list<TopoDS_Shape> Area::sortWires(const std::list<TopoDS_Shape> &shapes,
         FC_TIME_LOG(t,"plane merging");
     }
 
-    FC_DURATION_DECL_INIT(td);
+    //FC_DURATION_DECL_INIT(td);
 
     if(use_bound) {
         bounds.SetGap(0.0);
diff --git a/src/Mod/Path/libarea/PythonStuff.cpp b/src/Mod/Path/libarea/PythonStuff.cpp
index 475e60a28c..a1b3005e72 100644
--- a/src/Mod/Path/libarea/PythonStuff.cpp
+++ b/src/Mod/Path/libarea/PythonStuff.cpp
@@ -75,8 +75,10 @@ static void print_curve(const CCurve& c)
 	std::size_t nvertices = c.m_vertices.size();
 #if defined SIZEOF_SIZE_T && SIZEOF_SIZE_T == 4
 	printf("number of vertices = %d\n", nvertices);
-#else
+#elif defined(_WIN32)
 	printf("number of vertices = %Iu\n", nvertices);
+#else
+	printf("number of vertices = %lu\n", nvertices);
 #endif
 	int i = 0;
 	for(std::list<CVertex>::const_iterator It = c.m_vertices.begin(); It != c.m_vertices.end(); It++, i++)
diff --git a/src/Mod/TechDraw/App/DrawViewPart.cpp b/src/Mod/TechDraw/App/DrawViewPart.cpp
index 096f9d2ee7..ef6deab37e 100644
--- a/src/Mod/TechDraw/App/DrawViewPart.cpp
+++ b/src/Mod/TechDraw/App/DrawViewPart.cpp
@@ -118,8 +118,7 @@ using namespace std;
 PROPERTY_SOURCE(TechDraw::DrawViewPart, TechDraw::DrawView)
 
 DrawViewPart::DrawViewPart(void) : 
-    geometryObject(0),
-    on1(true)
+    geometryObject(0)
 {
     static const char *group = "Projection";
     static const char *sgroup = "HLR Parameters";
diff --git a/src/Mod/TechDraw/App/DrawViewPart.h b/src/Mod/TechDraw/App/DrawViewPart.h
index fde103cf6e..37f572ee34 100644
--- a/src/Mod/TechDraw/App/DrawViewPart.h
+++ b/src/Mod/TechDraw/App/DrawViewPart.h
@@ -218,7 +218,6 @@ protected:
 
 private:
     bool nowUnsetting;
-    bool on1;
 /*    bool m_restoreComplete;*/
 
 };
diff --git a/src/Mod/TechDraw/Gui/QGMText.cpp b/src/Mod/TechDraw/Gui/QGMText.cpp
index f5e59e8467..57a3a19a47 100644
--- a/src/Mod/TechDraw/Gui/QGMText.cpp
+++ b/src/Mod/TechDraw/Gui/QGMText.cpp
@@ -49,7 +49,7 @@ QGMText::QGMText() :
 
 QVariant QGMText::itemChange(GraphicsItemChange change, const QVariant &value)
 {
-    QPointF newPos(0.0,0.0);
+    //QPointF newPos(0.0,0.0);
     if(change == ItemPositionHasChanged && scene()) {
         Q_EMIT dragging();
     }
diff --git a/src/Mod/TechDraw/Gui/QGTracker.cpp b/src/Mod/TechDraw/Gui/QGTracker.cpp
index bd9eb7badf..244cc62ed0 100644
--- a/src/Mod/TechDraw/Gui/QGTracker.cpp
+++ b/src/Mod/TechDraw/Gui/QGTracker.cpp
@@ -52,11 +52,9 @@
 using namespace TechDrawGui;
 
 QGTracker::QGTracker(QGraphicsScene* inScene, TrackerMode m):
-    m_width(0),
     m_sleep(false),
     m_qgParent(nullptr),
-    m_lastClick(QPointF(FLT_MAX,FLT_MAX)),
-    m_2clickPending(false)
+    m_lastClick(QPointF(FLT_MAX,FLT_MAX))
 {
     setTrackerMode(m);
     if (inScene != nullptr) {
diff --git a/src/Mod/TechDraw/Gui/QGTracker.h b/src/Mod/TechDraw/Gui/QGTracker.h
index 9f65a48304..fff277782b 100644
--- a/src/Mod/TechDraw/Gui/QGTracker.h
+++ b/src/Mod/TechDraw/Gui/QGTracker.h
@@ -92,7 +92,6 @@ protected:
     double getTrackerWeight();
 
 private:
-    double m_width;
     QGraphicsPathItem* m_track;
     QPointF m_segBegin;
     QPointF m_segEnd;
@@ -103,7 +102,6 @@ private:
     QPen m_trackPen;
     QPen m_tailPen;
     QPointF m_lastClick;
-    bool m_2clickPending;
 };
 
 } // namespace
diff --git a/src/Mod/TechDraw/Gui/ViewProviderPage.h b/src/Mod/TechDraw/Gui/ViewProviderPage.h
index bbfe423a2f..cb29a457e7 100644
--- a/src/Mod/TechDraw/Gui/ViewProviderPage.h
+++ b/src/Mod/TechDraw/Gui/ViewProviderPage.h
@@ -98,7 +98,6 @@ private:
     QPointer<MDIViewPage> m_mdiView;
     bool m_docReady;
     std::string m_pageName;
-    bool m_frameState;
     QGVPage* m_graphicsView;
 };