diff --git a/GeoModelCore/GeoModelKernel/GeoModelKernel/GeoTwistedTrap.h b/GeoModelCore/GeoModelKernel/GeoModelKernel/GeoTwistedTrap.h
index df85bb59f297d181216ddb79e0c85ec0ee100324..e88cc4665ab9bea7e634b84ee4e96ccb47ede466 100644
--- a/GeoModelCore/GeoModelKernel/GeoModelKernel/GeoTwistedTrap.h
+++ b/GeoModelCore/GeoModelKernel/GeoModelKernel/GeoTwistedTrap.h
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
 
 #ifndef GEOMODELKERNEL_GEOTWISTEDTRAP_H
@@ -113,12 +113,7 @@ class GeoTwistedTrap : public GeoShape
   double m_dx3;
   double m_dx4;
   double m_dz;        // Half-length along the z axis
-  double m_dx ;       // maximum side in x
-  double m_dy ;       // maximum side in y
   double m_alph ;
-  double m_tAlph ;    // std::tan(fAlph)
-  double m_deltaX ;
-  double m_deltaY ;
   double m_phiTwist;  // twist angle ( dphi in surface equation)
     
   const double m_CarTolerance = 1E-9 * SYSTEM_OF_UNITS::mm;
diff --git a/GeoModelCore/GeoModelKernel/src/GeoMaterialManager.cxx b/GeoModelCore/GeoModelKernel/src/GeoMaterialManager.cxx
index e500536a39cbdf4ed7cd291b8820f3e4ebf71ef9..93492a1c69a41097fc502f729f5e687042685322 100644
--- a/GeoModelCore/GeoModelKernel/src/GeoMaterialManager.cxx
+++ b/GeoModelCore/GeoModelKernel/src/GeoMaterialManager.cxx
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
 
 #include "GeoModelKernel/GeoMaterialManager.h"
@@ -18,7 +18,7 @@ GeoMaterialManager* GeoMaterialManager::s_instance{nullptr};
 
 class Impl {
 public:
-  Impl(GeoMaterialManager* man)
+  Impl(GeoMaterialManager* /*man*/)
   {}
   ~Impl(){}
 
diff --git a/GeoModelCore/GeoModelKernel/src/GeoTwistedTrap.cxx b/GeoModelCore/GeoModelKernel/src/GeoTwistedTrap.cxx
index 2f00d98282389b870e4cc67c8f5c6a3b606cecc9..12a9ff9f8822c531fc6e11fdba8870838ef91eff 100755
--- a/GeoModelCore/GeoModelKernel/src/GeoTwistedTrap.cxx
+++ b/GeoModelCore/GeoModelKernel/src/GeoTwistedTrap.cxx
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
 
 #include "GeoModelKernel/GeoTwistedTrap.h"
@@ -15,9 +15,7 @@ GeoTwistedTrap::GeoTwistedTrap(double  pPhiTwist,
                                double  pDx2,
                                double  pDy,
                                double  pDz )
-: m_phiTwist(pPhiTwist),
-m_dz(pDz),
-m_theta(0.),
+: m_theta(0.),
 m_phi(0.),
 m_dy1(pDy),
 m_dx1(pDx1),
@@ -25,7 +23,9 @@ m_dx2(pDx2),
 m_dy2(pDy),
 m_dx3(pDx1),
 m_dx4(pDx2),
-m_alph(0.)
+m_dz(pDz),
+m_alph(0.),
+m_phiTwist(pPhiTwist)
 {
 }
 
@@ -41,9 +41,7 @@ GeoTwistedTrap(double  pPhiTwist,  // twist angle
                double  pDx3,    // half x length at +pDz,-pDy
                double  pDx4,    // half x length at +pDz,+pDy
                double  pAlph )  // tilt angle
-: m_phiTwist(pPhiTwist),
-m_dz(pDz),
-m_theta(pTheta),
+: m_theta(pTheta),
 m_phi(pPhi),
 m_dy1(pDy1),
 m_dx1(pDx1),
@@ -51,7 +49,9 @@ m_dx2(pDx2),
 m_dy2(pDy2),
 m_dx3(pDx3),
 m_dx4(pDx4),
-m_alph(pAlph)
+m_dz(pDz),
+m_alph(pAlph),
+m_phiTwist(pPhiTwist)
 {
      if  ( ! ( ( m_dx1  > 2*m_CarTolerance)
             && ( m_dx2  > 2*m_CarTolerance)