diff --git a/include/boost/gil/gil_concept.hpp b/include/boost/gil/gil_concept.hpp
index 2299e3221..7c81a1e12 100644
--- a/include/boost/gil/gil_concept.hpp
+++ b/include/boost/gil/gil_concept.hpp
@@ -272,8 +272,7 @@ struct PointNDConcept {
         LT lt=axis_value<N-1>(point);
         axis_value<N-1>(point)=lt;
     
-        value_type v=point[0];  ignore_unused_variable_warning(v);
-        point[0]=point[0];
+//        value_type v=point[0];  ignore_unused_variable_warning(v);
     }
     P point;
 };
@@ -456,11 +455,12 @@ namespace detail {
     template <typename T>
     struct ChannelIsMutableConcept {
         void constraints() {
-            c=c;
+            c1=c2;
             using std::swap;
-            swap(c,c);
+            swap(c1,c2);
         }
-        T c;
+        T c1;
+        T c2;
     };
 }
 
@@ -951,8 +951,10 @@ struct MutableHomogeneousPixelConcept {
     void constraints() {
         gil_function_requires<HomogeneousPixelConcept<P> >();
         gil_function_requires<MutableHomogeneousColorBaseConcept<P> >();
-        p[0]=p[0];
+        p[0]=v;
+        v=p[0];
     }
+	typename P::template element_type<P>::type v;
     P p;
 };