diff --git a/Alpha_wrap_3/test/Alpha_wrap_3/alpha_wrap_validation.h b/Alpha_wrap_3/test/Alpha_wrap_3/alpha_wrap_validation.h
index 0a88e9ec302..c9445c9e9c5 100644
--- a/Alpha_wrap_3/test/Alpha_wrap_3/alpha_wrap_validation.h
+++ b/Alpha_wrap_3/test/Alpha_wrap_3/alpha_wrap_validation.h
@@ -85,7 +85,7 @@ bool check_edge_length(const TriangleMesh& output_mesh,
   }
 
   return true;
-};
+}
 
 template <typename ConcurrencyTag = CGAL::Sequential_tag,
           typename TriangleMesh, typename FT,
diff --git a/BGL/test/BGL/next.cpp b/BGL/test/BGL/next.cpp
index aa7a53d5235..fd69cc00304 100644
--- a/BGL/test/BGL/next.cpp
+++ b/BGL/test/BGL/next.cpp
@@ -29,7 +29,7 @@ namespace std {
   struct iterator_traits<Toto::Descriptor> {
 
   };
-};
+}
 
 
 namespace Nested {
diff --git a/Cone_spanners_2/include/CGAL/Compute_cone_boundaries_2.h b/Cone_spanners_2/include/CGAL/Compute_cone_boundaries_2.h
index 7ecd77651fb..74e12a8f4db 100644
--- a/Cone_spanners_2/include/CGAL/Compute_cone_boundaries_2.h
+++ b/Cone_spanners_2/include/CGAL/Compute_cone_boundaries_2.h
@@ -207,7 +207,7 @@ public:
 
         return result;
 
-    };      // end of operator()
+    }   // end of operator()
 };      // end of functor specialization: Compute_cone_..._2
 
 }  // namespace CGAL
diff --git a/Kernel_23/test/Kernel_23/test_approximate_dihedral_angle_3.cpp b/Kernel_23/test/Kernel_23/test_approximate_dihedral_angle_3.cpp
index 233656236b2..b39ce5c01e7 100644
--- a/Kernel_23/test/Kernel_23/test_approximate_dihedral_angle_3.cpp
+++ b/Kernel_23/test/Kernel_23/test_approximate_dihedral_angle_3.cpp
@@ -33,4 +33,4 @@ int main() {
     std::cout << approx << "  -- " << expected << '\n';
     assert( std::abs(approx - expected) < 0.1 );
   }
-};
+}
diff --git a/Number_types/include/CGAL/FPU.h b/Number_types/include/CGAL/FPU.h
index d5a123608c4..429941be991 100644
--- a/Number_types/include/CGAL/FPU.h
+++ b/Number_types/include/CGAL/FPU.h
@@ -278,7 +278,7 @@ inline __m128d swap_m128d(__m128d x){
 # ifdef __llvm__
   return __builtin_shufflevector(x, x, 1, 0);
 # elif defined __GNUC__ && !defined __INTEL_COMPILER
-  return __builtin_shuffle(x, (__m128i){ 1, 0 });
+  return __extension__ __builtin_shuffle(x, (__m128i){ 1, 0 });
 # else
   return _mm_shuffle_pd(x, x, 1);
 # endif
diff --git a/Number_types/include/CGAL/Interval_nt.h b/Number_types/include/CGAL/Interval_nt.h
index b23d286656d..47a68093191 100644
--- a/Number_types/include/CGAL/Interval_nt.h
+++ b/Number_types/include/CGAL/Interval_nt.h
@@ -49,7 +49,7 @@
 // gcc's __builtin_constant_p does not like arguments with side effects. Be
 // careful not to use this macro for something that the compiler will have
 // trouble eliminating as dead code.
-# define CGAL_CST_TRUE(X) ({ bool _ugly_ = (X); __builtin_constant_p(_ugly_) && _ugly_; })
+# define CGAL_CST_TRUE(X) __extension__ ({ bool _ugly_ = (X); __builtin_constant_p(_ugly_) && _ugly_; })
 #else
 # define CGAL_CST_TRUE(X) false
 #endif
diff --git a/Number_types/include/CGAL/boost_mp.h b/Number_types/include/CGAL/boost_mp.h
index 7332d2b5b47..340e423ad67 100644
--- a/Number_types/include/CGAL/boost_mp.h
+++ b/Number_types/include/CGAL/boost_mp.h
@@ -150,18 +150,27 @@ namespace Boost_MP_internal {
     CGAL_assertion(intv.first > 0.0);
     CGAL_assertion(intv.second > 0.0);
 
+#ifdef CGAL_LITTLE_ENDIAN
     CGAL_assertion_code(
     union {
-#ifdef CGAL_LITTLE_ENDIAN
       struct { uint64_t man:52; uint64_t exp:11; uint64_t sig:1; } s;
-#else /* CGAL_BIG_ENDIAN */
-      //WARNING: untested!
-      struct { uint64_t sig:1; uint64_t exp:11; uint64_t man:52; } s;
-#endif
       double d;
     } conv;
+
     conv.d = intv.first;
     )
+#else
+    //WARNING: untested!
+    CGAL_assertion_code(
+    union {
+
+      struct { uint64_t sig:1; uint64_t exp:11; uint64_t man:52; } s;
+      double d;
+    } conv;
+
+    conv.d = intv.first;
+    )
+#endif
     // Check that the exponent of intv.inf is 52, which corresponds to a 53 bit integer
     CGAL_assertion(conv.s.exp - ((1 << (11 - 1)) - 1) == std::numeric_limits<double>::digits - 1);
 
diff --git a/Number_types/test/Number_types/CORE_Expr_ticket_4296.cpp b/Number_types/test/Number_types/CORE_Expr_ticket_4296.cpp
index e7e83503304..f85b4359591 100644
--- a/Number_types/test/Number_types/CORE_Expr_ticket_4296.cpp
+++ b/Number_types/test/Number_types/CORE_Expr_ticket_4296.cpp
@@ -209,5 +209,5 @@ int main() {
 
   assert(v1 > v2);
 
-};
+}
 
diff --git a/Point_set_3/test/Point_set_3/point_set_test_join.cpp b/Point_set_3/test/Point_set_3/point_set_test_join.cpp
index c1650f1a0d2..d46066dba4f 100644
--- a/Point_set_3/test/Point_set_3/point_set_test_join.cpp
+++ b/Point_set_3/test/Point_set_3/point_set_test_join.cpp
@@ -88,4 +88,4 @@ int main (int, char**)
   print_point_set (ps1, "PS1 with PS3 properties + PS3 item copied = ");
 
   return EXIT_SUCCESS;
-};
+}
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/Mesh_3_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/Mesh_3_plugin.cpp
index 246a0fd2f8d..6aa0571c8b9 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/Mesh_3_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/Mesh_3_plugin.cpp
@@ -65,18 +65,18 @@ class Mesh_3_plugin :
   Q_INTERFACES(CGAL::Three::Polyhedron_demo_plugin_interface)
   Q_PLUGIN_METADATA(IID "com.geometryfactory.PolyhedronDemo.PluginInterface/1.0" FILE "mesh_3_plugin.json")
 
-  Q_PROPERTY(double angle READ get_angle WRITE set_angle);
+  Q_PROPERTY(double angle READ get_angle WRITE set_angle)
   Q_PROPERTY(double sharp_edges_angle_bound
              READ get_sharp_edges_angle_bound
-             WRITE set_sharp_edges_angle_bound);
-  Q_PROPERTY(double edges_sizing READ get_edges_sizing WRITE set_edges_sizing);
-  Q_PROPERTY(double facets_sizing READ get_facets_sizing WRITE set_facets_sizing);
-  Q_PROPERTY(double approx READ get_approx WRITE set_approx);
-  Q_PROPERTY(double tets_sizing READ get_tets_sizing WRITE set_tets_sizing);
-  Q_PROPERTY(double tets_shape READ get_tets_shape WRITE set_tets_shape);
-  Q_PROPERTY(bool protect_features READ get_protect_features WRITE set_protect_features);
-  Q_PROPERTY(bool protect_borders READ get_protect_borders WRITE set_protect_borders);
-  Q_PROPERTY(bool manifold_criterion READ get_manifold_criterion WRITE set_manifold_criterion);
+             WRITE set_sharp_edges_angle_bound)
+  Q_PROPERTY(double edges_sizing READ get_edges_sizing WRITE set_edges_sizing)
+  Q_PROPERTY(double facets_sizing READ get_facets_sizing WRITE set_facets_sizing)
+  Q_PROPERTY(double approx READ get_approx WRITE set_approx)
+  Q_PROPERTY(double tets_sizing READ get_tets_sizing WRITE set_tets_sizing)
+  Q_PROPERTY(double tets_shape READ get_tets_shape WRITE set_tets_shape)
+  Q_PROPERTY(bool protect_features READ get_protect_features WRITE set_protect_features)
+  Q_PROPERTY(bool protect_borders READ get_protect_borders WRITE set_protect_borders)
+  Q_PROPERTY(bool manifold_criterion READ get_manifold_criterion WRITE set_manifold_criterion)
 
   typedef CGAL::Mesh_facet_topology Mesh_facet_topology;
   Q_ENUMS(Mesh_facet_topology)
diff --git a/Triangulation_3/demo/Triangulation_3/Viewer.cpp b/Triangulation_3/demo/Triangulation_3/Viewer.cpp
index 62937f5a5bc..2483ea46879 100644
--- a/Triangulation_3/demo/Triangulation_3/Viewer.cpp
+++ b/Triangulation_3/demo/Triangulation_3/Viewer.cpp
@@ -1754,7 +1754,7 @@ void Viewer::beginSelection(const QPoint &point)
 {
   picking_pos = point;
   CGAL::QGLViewer::beginSelection(point);
-};
+}
 void Viewer::endSelection(const QPoint& p)
 {
   CGAL::QGLViewer::endSelection(p);