diff --git a/configure.ac b/configure.ac
index d533d5a1..c8959704 100644
--- a/configure.ac
+++ b/configure.ac
@@ -171,7 +171,7 @@ TEA_PUBLIC_TCL_HEADERS
 TEA_PUBLIC_TK_HEADERS
 
 AC_SUBST([TOGLLIBDIR], ["$togllibfl"])
-AC_CHECK_HEADER([togl.h])
+# AC_CHECK_HEADER([togl.h])
 AC_CHECK_HEADER([GL/gl.h])
 
 
@@ -190,7 +190,7 @@ case "${TEA_WINDOWINGSYSTEM}" in
 		;;
 	x11)
 		AC_SUBST(TOGL_WINDOWINGSYSTEM,TOGL_X11)
-		TEA_ADD_LIBS([-lGL -lXmu])
+		TEA_ADD_LIBS([-lGL -lXmu -lX11])
 		LIBGLU=-lGLU
 		;;
 	win32)
@@ -217,16 +217,24 @@ AM_CONDITIONAL([NGGUI], [test x$ngguion = xtrue])
 AM_CONDITIONAL([NGMKL], [test x$mklon = xtrue])
 AM_CONDITIONAL([NGPYTHON], [test x$pythonon = xtrue])
 
-AC_CHECK_HEADER(pthread.h)
+# AC_CHECK_HEADER(pthread.h)
 
-AC_CHECK_FUNCS([pow])
-AC_CHECK_FUNCS([floor])
-AC_CHECK_FUNCS([matherr])
-AC_CHECK_HEADERS([limits.h])
+# AC_CHECK_FUNCS([pow])
+# AC_CHECK_FUNCS([floor])
+# AC_CHECK_FUNCS([matherr])
+# AC_CHECK_HEADERS([limits.h])
 
-AC_CHECK_LIB(pthread, pthread_create)
+# AC_CHECK_LIB(pthread, pthread_create)
 
 
+# LDFLAGS+=" -L/usr/lib/Togl1.7"
+# AC_SEARCH_LIBS(Togl_Init,[Togl Togl1.7],
+#         MYTOGL_LIB=$LIBS
+#        LIBS="",
+#        ,
+#        [-lGL -lXmu -ltk8.5 -ltcl8.5])
+# echo "libs = $LIBS"
+# echo "TOGL_LIB = $MYTOGL_LIB"
 
 
 AC_CONFIG_FILES(Makefile libsrc/Makefile libsrc/csg/Makefile 
diff --git a/libsrc/csg/Makefile.am b/libsrc/csg/Makefile.am
index 2c9f9b75..dc40cec9 100644
--- a/libsrc/csg/Makefile.am
+++ b/libsrc/csg/Makefile.am
@@ -10,10 +10,6 @@ METASOURCES = AUTO
 
 lib_LTLIBRARIES = libcsg.la
 
-if NGGUI
-lib_LTLIBRARIES += libcsgvis.la 
-endif
-
 
 libcsg_la_SOURCES = algprim.cpp brick.cpp   \
 bspline2d.cpp csgeom.cpp csgparser.cpp curve2d.cpp edgeflw.cpp	       \
@@ -21,12 +17,16 @@ explicitcurve2d.cpp extrusion.cpp gencyl.cpp genmesh.cpp identify.cpp  \
 manifold.cpp meshsurf.cpp polyhedra.cpp revolution.cpp singularref.cpp \
 solid.cpp specpoin.cpp spline3d.cpp surface.cpp triapprox.cpp
 
+libcsg_la_LIBADD =  $(top_builddir)/libsrc/meshing/libmesh.la
+
+
+
+if NGGUI
+lib_LTLIBRARIES += libcsgvis.la 
 
 libcsgvis_la_SOURCES = vscsg.cpp csgpkg.cpp
-
-
 libcsgvis_la_LIBADD = libcsg.la
-libcsg_la_LIBADD =  $(top_builddir)/libsrc/meshing/libmesh.la
+endif
 
 #   $(top_builddir)/libsrc/geom2d/libgeom2d.la 
 
diff --git a/libsrc/csg/algprim.cpp b/libsrc/csg/algprim.cpp
index 09bad013..31f014cc 100644
--- a/libsrc/csg/algprim.cpp
+++ b/libsrc/csg/algprim.cpp
@@ -1608,7 +1608,7 @@ namespace netgen
     double abs2 = Abs2(v1);
     double tau = v1 * n;
     double rho = sqrt (abs2 - tau*tau);
-    double func = sqr (R - rho) + tau*tau - r*r;
+    // double func = sqr (R - rho) + tau*tau - r*r;
 
     Vec<3> gradabs2 = 2 * v1;
     Vec<3> gradtau = n;
diff --git a/libsrc/geom2d/genmesh2d.cpp b/libsrc/geom2d/genmesh2d.cpp
index 56dfcf96..9efc62a6 100644
--- a/libsrc/geom2d/genmesh2d.cpp
+++ b/libsrc/geom2d/genmesh2d.cpp
@@ -50,7 +50,7 @@ namespace netgen
     double sum = 0;
     for (int i = 1; i <= n; i++)
       {
-	double t = (i-0.5)*dt;
+	// double t = (i-0.5)*dt;
 	double fun = hi[i-1];
 	sum += dt / fun;
       }
diff --git a/libsrc/gprim/geomobjects.hpp b/libsrc/gprim/geomobjects.hpp
index c4e72aef..ea80f7ff 100644
--- a/libsrc/gprim/geomobjects.hpp
+++ b/libsrc/gprim/geomobjects.hpp
@@ -26,9 +26,16 @@ namespace netgen
   public:
     Point () { ; }
     Point (double ax) { for (int i = 0; i < D; i++) x[i] = ax; }
-    Point (double ax, double ay) { x[0] = ax; x[1] = ay; }
-    Point (double ax, double ay, double az)
-    { x[0] = ax; x[1] = ay; x[2] = az; }
+    Point (double ax, double ay) 
+    { 
+      // static_assert(D==2, "Point<D> constructor with 2 args called");
+      x[0] = ax; x[1] = ay; 
+    }
+    Point (double ax, double ay, double az) 
+    {
+      // static_assert(D==3, "Point<D> constructor with 3 args called");
+      x[0] = ax; x[1] = ay; x[2] = az; 
+    }
     Point (double ax, double ay, double az, double au)
     { x[0] = ax; x[1] = ay; x[2] = az; x[3] = au;}
 
@@ -57,10 +64,6 @@ namespace netgen
     operator const double* () const { return x; }
   };
 
-
-
-
-
   template <int D>
   class Vec
   {
@@ -71,9 +74,16 @@ namespace netgen
   public:
     Vec () { ; } // for (int i = 0; i < D; i++) x[i] = 0; }
     Vec (double ax) { for (int i = 0; i < D; i++) x[i] = ax; }
-    Vec (double ax, double ay) { x[0] = ax; x[1] = ay; }
+    Vec (double ax, double ay) 
+    { 
+      // static_assert(D==2, "Vec<D> constructor with 2 args called");
+      x[0] = ax; x[1] = ay; 
+    }
     Vec (double ax, double ay, double az)
-    { x[0] = ax; x[1] = ay; x[2] = az; }
+    { 
+      // static_assert(D==3, "Vec<D> constructor with 3 args called");
+      x[0] = ax; x[1] = ay; x[2] = az; 
+    }
     Vec (double ax, double ay, double az, double au)
     { x[0] = ax; x[1] = ay; x[2] = az; x[3] = au; }
 
diff --git a/libsrc/gprim/spline.cpp b/libsrc/gprim/spline.cpp
index b6789913..cc4c44d7 100644
--- a/libsrc/gprim/spline.cpp
+++ b/libsrc/gprim/spline.cpp
@@ -101,13 +101,17 @@ namespace netgen
   template<int D>
   inline Point<D> SplineSeg3<D> :: GetPoint (double t) const
   {
-    double x, y, w;
     double b1, b2, b3;
 
     b1 = (1-t)*(1-t);
     b2 = weight * t * (1-t);
     b3 = t * t;
 
+    Vec<D> hp = b1 * Vec<D>(p1) + b2 * Vec<D>(p2) + b3 * Vec<D>(p3);
+    double w = b1+b2+b3;
+    return Point<D> ((1.0/w)*hp);
+    /*
+    double x, y, w;
     x = p1(0) * b1 + p2(0) * b2 + p3(0) * b3;
     y = p1(1) * b1 + p2(1) * b2 + p3(1) * b3;
     w = b1 + b2 + b3;
@@ -119,6 +123,7 @@ namespace netgen
       }
     else
       return Point<D> (x/w, y/w);
+    */
   }
 
 
diff --git a/libsrc/gprim/spline.hpp b/libsrc/gprim/spline.hpp
index 10a6f9a1..a872d6e9 100644
--- a/libsrc/gprim/spline.hpp
+++ b/libsrc/gprim/spline.hpp
@@ -483,19 +483,38 @@ namespace netgen
 	if ( w1>M_PI )   w1 -= 2*M_PI;
       }
   }
- 
 
+  /*
   template<int D>
   Point<D> CircleSeg<D> :: GetPoint (double t) const
   {
     if (t >= 1.0)  { return p3; }
-     
     double phi = StartAngle() + t*(EndAngle()-StartAngle());
     Vec<D>  tmp(cos(phi),sin(phi));
-     
+    return pm + Radius()*tmp;
+  }
+  */
+  template<>
+  inline Point<3> CircleSeg<3> :: GetPoint (double t) const
+  {
+    // not really useful, but keep it as it was ...
+    if (t >= 1.0)  { return p3; }
+    double phi = StartAngle() + t*(EndAngle()-StartAngle());
+    Vec<3>  tmp(cos(phi),sin(phi),0);
     return pm + Radius()*tmp;
   }
   
+  template<>
+  inline Point<2> CircleSeg<2> :: GetPoint (double t) const
+  {
+    if (t >= 1.0)  { return p3; }
+     
+    double phi = StartAngle() + t*(EndAngle()-StartAngle());
+    Vec<2>  tmp(cos(phi),sin(phi));
+     
+    return pm + Radius()*tmp;
+  }
+
   template<int D>
   void CircleSeg<D> :: GetCoeff (Vector & coeff) const
   { 
diff --git a/libsrc/interface/nginterface.cpp b/libsrc/interface/nginterface.cpp
index adbe657a..066ffe46 100644
--- a/libsrc/interface/nginterface.cpp
+++ b/libsrc/interface/nginterface.cpp
@@ -1626,6 +1626,10 @@ int Ng_GetNVertexElements (int vnr)
           if ( ((*mesh)[i][0] == vnr) || ((*mesh)[i][1] == vnr) ) cnt++;
         return cnt;
       }
+    default:
+      cerr << "error: mesh->GetDimension() gives " 
+           << mesh->GetDimension() << endl;
+      return 0;
     }
 }
 
diff --git a/libsrc/interface/readtetmesh.cpp b/libsrc/interface/readtetmesh.cpp
index 1258068b..db18f2ed 100644
--- a/libsrc/interface/readtetmesh.cpp
+++ b/libsrc/interface/readtetmesh.cpp
@@ -48,7 +48,7 @@ namespace netgen
     int modelverts,modeledges,modelfaces,modelcells;
     Point3d p;
     int numObj3D,numObj2D,numObj1D,numObj0D;
-    bool nullstarted;
+    // bool nullstarted;
     Array<int> eldom;
     int minId3D = -1, minId2D = -1;
     int maxId3D(-1), maxId2D(-1), maxId1D(-1), maxId0D(-1);
@@ -222,7 +222,7 @@ namespace netgen
           case 14:
             // EdgeID, NodeID0, NodeID1, Type (0=Reg 1=PMaster 2=PSlave 3=CPMaster 4=CPSlave), PID
             cout << "read edges" << endl;
-            nullstarted = false;
+            // nullstarted = false;
             segmentdata.SetSize(nedges);
             for(int i=0; i<nedges; i++)
               {
@@ -272,7 +272,7 @@ namespace netgen
               int segnum_ng[3];
               bool neg[3];
               cout << "read faces" << endl;
-              nullstarted = false;
+              // nullstarted = false;
               for(int i=0; i<nfaces; i++)
                 {
                   int trinum;
@@ -331,8 +331,8 @@ namespace netgen
                             }
                         }
                     }
-                  else
-                    nullstarted = true;
+                  // else
+                  //   nullstarted = true;
                 }
             }
             break;
@@ -397,7 +397,7 @@ namespace netgen
 #ifdef WIN32
                          << "%%\r"
 #else
-                         << "\%\r"
+                         << "%\r"
 #endif 
                          << flush;
                   in >> elemid;
diff --git a/libsrc/interface/readuser.cpp b/libsrc/interface/readuser.cpp
index f21466af..3f798a93 100644
--- a/libsrc/interface/readuser.cpp
+++ b/libsrc/interface/readuser.cpp
@@ -89,7 +89,7 @@ namespace netgen
          strcmp (&filename[strlen (filename)-4], ".unv") == 0 )
       {  
         char reco[100];
-        int invert;
+        // int invert;
       
         ifstream in(filename);
 
diff --git a/libsrc/meshing/hprefinement.cpp b/libsrc/meshing/hprefinement.cpp
index 21b1d1fa..97285259 100644
--- a/libsrc/meshing/hprefinement.cpp
+++ b/libsrc/meshing/hprefinement.cpp
@@ -544,6 +544,13 @@ namespace netgen
 	hps = &refhex_1f_0e_0v; break;
       case HP_HEX_1FA_1FB_0E_0V: 
 	hps = &refhex_1fa_1fb_0e_0v; break; 
+
+
+
+      default:
+        {
+          hps = NULL;
+        }
       }
 
     /*
@@ -1518,7 +1525,7 @@ namespace netgen
 	  }
 	for(SurfaceElementIndex i=0;i<mesh.GetNSE(); i++) 
 	  { 
-	    Element2d el = mesh[i] ;
+	    // Element2d el = mesh[i] ;
 	    HPRefElement & hpel = hpelements[mesh[i].hp_elnr];
 	    const ELEMENT_EDGE * edges = MeshTopology::GetEdges1 (mesh[i].GetType());
 	    double dist[3] = {0,0,0}; 
@@ -1877,8 +1884,8 @@ bool CheckSingularities(Mesh & mesh, INDEX_2_HASHTABLE<int> & edges, INDEX_2_HAS
 	    }
 	  case HP_HEX:
 	    { 
-	      hpel.type = hpel.type = ClassifyHex(hpel, edges, edgepoint_dom, cornerpoint, edgepoint, faces,
-						  face_edges, surf_edges, facepoint); 	    	    
+	      hpel.type = ClassifyHex(hpel, edges, edgepoint_dom, cornerpoint, edgepoint, faces,
+                                      face_edges, surf_edges, facepoint); 	    	    
 	      break; 
 	    } 
 	  case HP_TRIG: 
diff --git a/libsrc/meshing/improve2.hpp b/libsrc/meshing/improve2.hpp
index dad6a3ae..9c3c1be1 100644
--- a/libsrc/meshing/improve2.hpp
+++ b/libsrc/meshing/improve2.hpp
@@ -14,6 +14,7 @@ class MeshOptimize2d
 public:
   ///
   MeshOptimize2d ();
+  virtual ~MeshOptimize2d() { ; }
   ///
   void ImproveMesh (Mesh & mesh2d, const MeshingParameters & mp);
   void ImproveMeshJacobian (Mesh & mesh2d, const MeshingParameters & mp);
diff --git a/libsrc/meshing/localh.cpp b/libsrc/meshing/localh.cpp
index 99767360..0b0fa963 100644
--- a/libsrc/meshing/localh.cpp
+++ b/libsrc/meshing/localh.cpp
@@ -474,7 +474,7 @@ namespace netgen
 
     root->flags.isinner = 0;
 
-    Point<2> rpmid(root->xmid[0], root->xmid[1], root->xmid[2]);
+    Point<2> rpmid(root->xmid[0], root->xmid[1]);   // , root->xmid[2]);
     Vec<2> rv(root->h2, root->h2);
     Point<2> rx2 = rpmid + rv;
     // Point<2> rx1 = rpmid - rv;
diff --git a/libsrc/meshing/meshtool.cpp b/libsrc/meshing/meshtool.cpp
index 4a349ac9..271b8747 100644
--- a/libsrc/meshing/meshtool.cpp
+++ b/libsrc/meshing/meshtool.cpp
@@ -356,18 +356,16 @@ namespace netgen
     if(teterrpow < 1) teterrpow = 1;
 
     if (teterrpow == 1)
-    {
-       errpow = err;
-       grad = graderr;
-    }
-
-    if (teterrpow == 2)
+      {
+        errpow = err;
+        grad = graderr;
+      }
+    else if (teterrpow == 2)
       {
         errpow = err*err;   
         grad = (2 * err) * graderr;
       }
-
-    if(teterrpow > 2)
+    else 
       {
         errpow = pow (err, teterrpow);
         grad = (teterrpow * errpow / err) * graderr;
diff --git a/libsrc/meshing/parser3.cpp b/libsrc/meshing/parser3.cpp
index c6ccba4a..a661fced 100644
--- a/libsrc/meshing/parser3.cpp
+++ b/libsrc/meshing/parser3.cpp
@@ -869,7 +869,7 @@ void vnetrule :: LoadRule (istream & ist)
       
       for (k = 1; k <= freesetfaces.Size(); k++)
 	{
-          threeint tr = freesetfaces.Get(k);
+          // threeint tr = freesetfaces.Get(k);
 
 	  for (l = k+1; l <= freesetfaces.Size(); l++)
 	    {
diff --git a/libsrc/meshing/ruler3.cpp b/libsrc/meshing/ruler3.cpp
index 3b6f7a91..c83b1db5 100644
--- a/libsrc/meshing/ruler3.cpp
+++ b/libsrc/meshing/ruler3.cpp
@@ -229,7 +229,8 @@ int Meshing3 :: ApplyRules
       NgProfiler::RegionTimer regx1(base);
       NgProfiler::RegionTimer regx(base+ri);
 
-      sprintf (problems.Elem(ri), "");
+      // sprintf (problems.Elem(ri), "");
+      *problems.Elem(ri) = '\0';
 
       rule = rules.Get(ri);
       
diff --git a/libsrc/meshing/smoothing3.cpp b/libsrc/meshing/smoothing3.cpp
index 24f1ef71..20c8e461 100644
--- a/libsrc/meshing/smoothing3.cpp
+++ b/libsrc/meshing/smoothing3.cpp
@@ -310,7 +310,7 @@ namespace netgen
     PointFunction (Mesh::T_POINTS & apoints, 
 		   const Mesh::T_VOLELEMENTS & aelements,
 		   const MeshingParameters & amp);
-  
+    virtual ~PointFunction () { ; }
     virtual void SetPointIndex (PointIndex aactpind);
     void SetLocalH (double ah) { h = ah; }
     double GetLocalH () const { return h; }
diff --git a/ng/ngpkg.cpp b/ng/ngpkg.cpp
index 1e943381..04d96f70 100644
--- a/ng/ngpkg.cpp
+++ b/ng/ngpkg.cpp
@@ -2116,7 +2116,13 @@ namespace netgen
       return TCL_ERROR;
     }
     sprintf(str,"rm %s", filename2);
-    system(str);
+
+    err = system(str);
+    if (err != 0)
+      {
+        Tcl_SetResult (Togl_Interp(togl), (char*)"Cannot delete temporary file", TCL_VOLATILE);
+        return TCL_ERROR;
+      }
 
     return TCL_OK;
   }