diff --git a/OpenNL/include/CGAL/OpenNL/linear_solver.h b/OpenNL/include/CGAL/OpenNL/linear_solver.h
index fa83ebdc05f..960585160a0 100644
--- a/OpenNL/include/CGAL/OpenNL/linear_solver.h
+++ b/OpenNL/include/CGAL/OpenNL/linear_solver.h
@@ -336,28 +336,28 @@ public:
 
     void end_row() {
         if(least_squares_) {
-            unsigned int nf = af_.size() ;
-            unsigned int nl = al_.size() ;
-            for(unsigned int i=0; i<nf; i++) {
-                for(unsigned int j=0; j<nf; j++) {
+            std::size_t nf = af_.size() ;
+            std::size_t nl = al_.size() ;
+            for(std::size_t i=0; i<nf; i++) {
+                for(std::size_t j=0; j<nf; j++) {
                     A_->add_coef(if_[i], if_[j], af_[i] * af_[j]) ;
                 }
             }
             CoeffType S = - bk_ ;
-            for(unsigned int j=0; j<nl; j++) {
+            for(std::size_t j=0; j<nl; j++) {
                 S += al_[j] * xl_[j] ;
             }
-            for(unsigned int i=0; i<nf; i++) {
+            for(std::size_t i=0; i<nf; i++) {
                 (*b_)[if_[i]] -= af_[i] * S ;
             }
         } else {
-            unsigned int nf = af_.size() ;
-            unsigned int nl = al_.size() ;
-            for(unsigned int i=0; i<nf; i++) {
+            std::size_t nf = af_.size() ;
+            std::size_t nl = al_.size() ;
+            for(std::size_t i=0; i<nf; i++) {
                 A_->add_coef(current_row_, if_[i], af_[i]) ;
             }
             (*b_)[current_row_] = bk_ ;
-            for(unsigned int i=0; i<nl; i++) {
+            for(std::size_t i=0; i<nl; i++) {
                 (*b_)[current_row_] -= al_[i] * xl_[i] ;
             }
         }
diff --git a/Polyhedron/demo/Polyhedron/Viewer.cpp b/Polyhedron/demo/Polyhedron/Viewer.cpp
index f47574727c5..0353d581a8c 100644
--- a/Polyhedron/demo/Polyhedron/Viewer.cpp
+++ b/Polyhedron/demo/Polyhedron/Viewer.cpp
@@ -477,7 +477,7 @@ void Viewer::endSelection(const QPoint& point)
     pickMatrix_[15]=1;
 }
 
-void Viewer::makeArrow(float R, int prec, qglviewer::Vec from, qglviewer::Vec to, qglviewer::Vec color, AxisData &data)
+void Viewer::makeArrow(double R, int prec, qglviewer::Vec from, qglviewer::Vec to, qglviewer::Vec color, AxisData &data)
 {
     qglviewer::Vec temp = to-from;
     QVector3D dir = QVector3D(temp.x, temp.y, temp.z);
@@ -555,7 +555,7 @@ void Viewer::makeArrow(float R, int prec, qglviewer::Vec from, qglviewer::Vec to
     for(int d = 0; d<360; d+= 360/prec)
     {
         //point A1
-        float D = d*M_PI/180.0;
+        double D = d*M_PI/180.0;
         QVector4D p(R*sin(D),0.66,R*cos(D), 1.0);
         QVector4D n(sin(D), 0, cos(D), 1.0);
         QVector4D pR = mat*p;
@@ -751,13 +751,13 @@ void Viewer::resizeGL(int w, int h)
     buffers[0].release();
 
     buffers[1].bind();
-    buffers[1].allocate(n_Axis.data(), n_Axis.size() * sizeof(float));
+    buffers[1].allocate(n_Axis.data(), static_cast<int>(n_Axis.size() * sizeof(float)));
     rendering_program.enableAttributeArray("normal");
     rendering_program.setAttributeBuffer("normal",GL_FLOAT,0,3);
     buffers[1].release();
 
     buffers[2].bind();
-    buffers[2].allocate(c_Axis.data(), c_Axis.size() * sizeof(float));
+    buffers[2].allocate(c_Axis.data(), static_cast<int>(c_Axis.size() * sizeof(float)));
     rendering_program.enableAttributeArray("colors");
     rendering_program.setAttributeBuffer("colors",GL_FLOAT,0,3);
     buffers[2].release();
diff --git a/Polyhedron/demo/Polyhedron/Viewer.h b/Polyhedron/demo/Polyhedron/Viewer.h
index 4841db07f29..f74c05335c1 100644
--- a/Polyhedron/demo/Polyhedron/Viewer.h
+++ b/Polyhedron/demo/Polyhedron/Viewer.h
@@ -67,7 +67,7 @@ protected:
   void keyPressEvent(QKeyEvent*);
   void pickMatrix(GLdouble x, GLdouble y, GLdouble width, GLdouble height,
                   GLint viewport[4]);
-  void makeArrow(float R, int prec, qglviewer::Vec from, qglviewer::Vec to, qglviewer::Vec color, AxisData &data);
+  void makeArrow(double R, int prec, qglviewer::Vec from, qglviewer::Vec to, qglviewer::Vec color, AxisData &data);
   void resizeGL(int w, int h);