diff --git a/src/geomlib/TRKTrack.h b/src/geomlib/TRKTrack.h
index 4e0c0d2..e462610 100644
--- a/src/geomlib/TRKTrack.h
+++ b/src/geomlib/TRKTrack.h
@@ -34,7 +34,7 @@ class TRKTrack : public TEveTrackPropagator {
    // Ctors and Dtor
    TRKTrack(Double_t chg, TVector3 x, TVector3 p);
    TRKTrack(const TRKTrack&);
-   TRKTrack& operator=(const TRKTrack&) = default ;
+   TRKTrack& operator=(const TRKTrack&) = delete ;
 
    virtual ~TRKTrack() {}
 
diff --git a/src/geomlib/TRungeKuttaTrack.h b/src/geomlib/TRungeKuttaTrack.h
index e74febe..4118b1a 100644
--- a/src/geomlib/TRungeKuttaTrack.h
+++ b/src/geomlib/TRungeKuttaTrack.h
@@ -70,7 +70,7 @@ class TRungeKuttaTrack : public THelicalTrack {
    void SetFromTrack(THelicalTrack& heltrack);
 
    // Utility methods
-   virtual void MoveTo(const TVector3 &globalPivot, 
+    virtual void MoveTo(const TVector3 &globalPivot, 
                              Double_t &step,     
 		                     TMatrixD  *FPtr = 0,    
 		                     TMatrixD  *F12Ptr = 0,    
@@ -80,6 +80,14 @@ class TRungeKuttaTrack : public THelicalTrack {
                              Double_t    &step,     
 		                     TKalMatrix  &FPtr);
 
+   // Do not allow calls to the base class method.
+   virtual void MoveTo(const TVector3 &,
+                             Double_t &,
+                             TMatrixD *,
+                             TMatrixD *,
+                       Bool_t   )
+   { std::abort(); }
+
    virtual TVector3 CalcXAt   (Double_t h) const;
    virtual TMatrixD CalcDxDa  (Double_t h) const;
    virtual TMatrixD CalcDxDphi(Double_t h) const;
diff --git a/src/geomlib/TTube.cxx b/src/geomlib/TTube.cxx
index e27d638..61988c8 100644
--- a/src/geomlib/TTube.cxx
+++ b/src/geomlib/TTube.cxx
@@ -117,6 +117,7 @@ Int_t TTube::CalcXingPointWith(const TVTrack  &hel,
             }
          }
          if (IsOnBarrel(xx)) return 1;
+         [[fallthrough]];
       default: // track hitting end cap part
          if (TMath::Abs(tnl) < 0.1) {
             return 0;
diff --git a/src/kallib/TKalMatrix.h b/src/kallib/TKalMatrix.h
index 7058f53..680364d 100644
--- a/src/kallib/TKalMatrix.h
+++ b/src/kallib/TKalMatrix.h
@@ -48,6 +48,8 @@ class TKalMatrix : public TMatrixD {
 
    TKalMatrix(const TRotation &r);
 
+   TKalMatrix& operator= (const TKalMatrix &orig) = default;
+
    virtual ~TKalMatrix() {}
 
   // virtual void  DebugPrint() const { DebugPrint( "", 5 , std::cerr ) ; }
diff --git a/src/kaltracklib/TKalTrackState.h b/src/kaltracklib/TKalTrackState.h
index 493f444..64aff26 100644
--- a/src/kaltracklib/TKalTrackState.h
+++ b/src/kaltracklib/TKalTrackState.h
@@ -60,6 +60,10 @@ class TKalTrackState : public TVKalState {
                            TKalMatrix	&F, 
                            TKalMatrix &Q) const;
 
+  virtual void  DebugPrint(std::ostream& os, Option_t *, Int_t  ) const
+  { DebugPrint(os); }
+  virtual void  DebugPrint(Option_t *, Int_t  ) const
+  { DebugPrint(); }
   void         DebugPrint() const ;
   void         DebugPrint( std::ostream& os ) const;
 
diff --git a/src/kaltracklib/TTrackFrame.h b/src/kaltracklib/TTrackFrame.h
index 0771568..84bec0b 100644
--- a/src/kaltracklib/TTrackFrame.h
+++ b/src/kaltracklib/TTrackFrame.h
@@ -39,7 +39,7 @@ class TTrackFrame {
    //rotation matrix.
    TTrackFrame(const TTrackFrame &lastFrame, const TVector3 &v, const TVector3 &b);
 
-   //TTrackFrame& operator=( const TTrackFrame& frame );
+   TTrackFrame& operator=( const TTrackFrame& frame ) = default;
 
    virtual ~TTrackFrame() {}