diff --git a/Kernel_d/include/CGAL/Kernel_d/function_objectsCd.h b/Kernel_d/include/CGAL/Kernel_d/function_objectsCd.h
index 12321c69166..143f482729e 100644
--- a/Kernel_d/include/CGAL/Kernel_d/function_objectsCd.h
+++ b/Kernel_d/include/CGAL/Kernel_d/function_objectsCd.h
@@ -143,6 +143,7 @@ public:
     template <class Forward_iterator>
     result_type operator()(Forward_iterator start, Forward_iterator end) const
     {
+        CGAL_USE(end);
         CGAL_assertion(start!=end);
         int d = start->dimension();
         Matrix M(d);
diff --git a/Nef_2/include/CGAL/Nef_2/Polynomial.h b/Nef_2/include/CGAL/Nef_2/Polynomial.h
index 5d312528aac..ae99f11f49b 100644
--- a/Nef_2/include/CGAL/Nef_2/Polynomial.h
+++ b/Nef_2/include/CGAL/Nef_2/Polynomial.h
@@ -692,7 +692,7 @@ class Polynomial<int> :
   Polynomial<int> abs() const
   /*{\Xop returns |-\Mvar| if |\Mvar.sign()==NEGATIVE| and |\Mvar| 
   otherwise.}*/
-  { if ( sign()==CGAL::NEGATIVE ) return -*this; return *this; }
+  { return ( sign()==CGAL::NEGATIVE ) ? - *this : *this; }
 
   int content() const
   /*{\Xop returns the content of |\Mvar| (the gcd of its coefficients).
@@ -993,7 +993,7 @@ determines the sign for the limit process $x \rightarrow \infty$.
   Polynomial<double> abs() const
   /*{\Xop returns |-\Mvar| if |\Mvar.sign()==NEGATIVE| and |\Mvar| 
   otherwise.}*/
-  { if ( sign()==CGAL::NEGATIVE ) return -*this; return *this; }
+  { return ( sign()==CGAL::NEGATIVE ) ? - *this : *this; }
 
 
   double content() const