I'm having some trouble iterating over a 2-dimensional multi_array in reverse order. I'm using boost 1.38 with gcc-4.2.4 and the following code won't compile with the error given below: #include <boost/multi_array.hpp> template< typename It > void iterate_over( It begin, It end ) { while( end != begin ) { begin->end() - begin->begin(); ++begin; } } void test() { boost::multi_array< double, 2 > m; iterate_over( m.begin(), m.end() ); // works fine iterate_over( m.rbegin(), m.rend() ); // causes error } This looks to me like a bug in the implementation of the reverse iterator for multi_array. Am I wrong? John. /home/john/Dev/ThirdParty/boost/boost_1_38_0/boost/iterator/iterator_facade.hpp: In static member function ‘static typename boost::mpl::if_<boost::is_reference<Reference>, Pointer, boost::detail::operator_arrow_proxy<ValueType> >::type boost::detail::operator_arrow_result<ValueType, Reference, Pointer>::make(Reference) [with ValueType = boost::multi_array<double, 1ul, std::allocator<double> >, Reference = boost::detail::multi_array::sub_array<double, 1ul>, Pointer = boost::multi_array<double, 1ul, std::allocator<double> >*]’: /home/john/Dev/ThirdParty/boost/boost_1_38_0/boost/iterator/iterator_facade.hpp:648: instantiated from ‘typename boost::detail::operator_arrow_result<typename boost::detail::iterator_facade_types<Value, CategoryOrTraversal, Reference, Difference>::value_type, Reference, typename boost::detail::iterator_facade_types<Value, CategoryOrTraversal, Reference, Difference>::pointer>::type boost::iterator_facade<I, V, TC, R, D>::operator->() const [with Derived = boost::reverse_iterator<boost::detail::multi_array::array_iterator<double, double*, mpl_::size_t<2ul>, boost::detail::multi_array::sub_array<double, 1ul> > >, Value = boost::multi_array<double, 1ul, std::allocator<double> >, CategoryOrTraversal = boost::detail::iterator_category_with_traversal<std::input_iterator_tag, boost::random_access_traversal_tag>, Reference = boost::detail::multi_array::sub_array<double, 1ul>, Difference = long int]’ src/sandbox/seqan_sandbox.cpp:12: instantiated from ‘void iterate_over(It, It) [with It = boost::reverse_iterator<boost::detail::multi_array::array_iterator<double, double*, mpl_::size_t<2ul>, boost::detail::multi_array::sub_array<double, 1ul> > >]’ src/sandbox/seqan_sandbox.cpp:22: instantiated from here /home/john/Dev/ThirdParty/boost/boost_1_38_0/boost/iterator/iterator_facade.hpp:326: error: no matching function for call to ‘implicit_cast(boost::detail::multi_array::sub_array<double, 1ul>*)’