diff --git a/boost/numeric/ublas/operation.hpp b/boost/numeric/ublas/operation.hpp
index 16b7c02..ecea75d 100644
--- a/boost/numeric/ublas/operation.hpp
+++ b/boost/numeric/ublas/operation.hpp
@@ -108,7 +108,6 @@ namespace boost { namespace numeric { namespace ublas {
         typedef L1 layout_type;
 
         size_type size1 = e1.size1();
-        size_type size2 = e1.size2();
 
         if (init) {
             noalias(v) = zero_vector<value_type>(size1);