Add compile-time check to make sure allocator_type::value_type and container's value_type are the same type.

include/boost/container/deque.hpp

@@ -1026,6 +1026,11 @@ class deque : protected deque_base<typename real_allocator<T, Allocator>::type,
    #ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
 
    private:                      // Internal typedefs
+
+   //`allocator_type::value_type` must match container's `value type`. If this
+   //assertion fails, please review your allocator definition. 
+   BOOST_CONTAINER_STATIC_ASSERT((dtl::is_same<value_type, typename allocator_traits<ValAllocator>::value_type>::value));
+
    BOOST_COPYABLE_AND_MOVABLE(deque)
    typedef typename Base::ptr_alloc_ptr index_pointer;
    typedef allocator_traits<ValAllocator>                  allocator_traits_type;

include/boost/container/detail/flat_tree.hpp

@@ -592,6 +592,10 @@ class flat_tree
    typedef typename container_type::reverse_iterator         reverse_iterator;
    typedef typename container_type::const_reverse_iterator   const_reverse_iterator;
 
+   //`allocator_type::value_type` must match container's `value type`. If this
+   //assertion fails, please review your allocator definition. 
+   BOOST_CONTAINER_STATIC_ASSERT((is_same<value_type, typename allocator_traits_type::value_type>::value));
+
    //!Standard extension
    typedef BOOST_INTRUSIVE_OBTAIN_TYPE_WITH_DEFAULT
       (boost::container::dtl::, container_type
@@ -733,7 +737,8 @@ class flat_tree
    }
 
    inline ~flat_tree()
-   {}
+   {
+   }
 
    inline flat_tree&  operator=(BOOST_COPY_ASSIGN_REF(flat_tree) x)
    {  m_data = x.m_data;   return *this;  }

include/boost/container/detail/tree.hpp

@@ -456,6 +456,10 @@ class tree
 
    private:
 
+   //`allocator_type::value_type` must match container's `value type`. If this
+   //assertion fails, please review your allocator definition. 
+   BOOST_CONTAINER_STATIC_ASSERT((dtl::is_same<value_type, typename allocator_traits<allocator_type>::value_type>::value));
+
    typedef key_node_pred<key_compare, key_of_value_t, Node>  KeyNodeCompare;
 
    public:

include/boost/container/devector.hpp

@@ -173,6 +173,11 @@ class devector
 
    #ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
    private:
+
+   //`allocator_type::value_type` must match container's `value type`. If this
+   //assertion fails, please review your allocator definition. 
+   BOOST_CONTAINER_STATIC_ASSERT((dtl::is_same<value_type, typename allocator_traits<allocator_type>::value_type>::value));
+
    BOOST_COPYABLE_AND_MOVABLE(devector)
 
    // Guard to deallocate buffer on exception

include/boost/container/list.hpp

@@ -1378,6 +1378,10 @@ class list
    #ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
    private:
 
+   //`allocator_type::value_type` must match container's `value type`. If this
+   //assertion fails, please review your allocator definition. 
+   BOOST_CONTAINER_STATIC_ASSERT((dtl::is_same<value_type, typename allocator_traits_type::value_type>::value));
+
    void priv_move_assign(BOOST_RV_REF(list) x, dtl::bool_<true> /*steal_resources*/)
    {
       //Destroy objects but retain memory in case x reuses it in the future

include/boost/container/slist.hpp

@@ -1565,6 +1565,11 @@ class slist
 
    #ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
    private:
+
+   //`allocator_type::value_type` must match container's `value type`. If this
+   //assertion fails, please review your allocator definition. 
+   BOOST_CONTAINER_STATIC_ASSERT((dtl::is_same<value_type, typename allocator_traits_type::value_type>::value));
+
    void priv_move_assign(BOOST_RV_REF(slist) x, dtl::bool_<true> /*steal_resources*/)
    {
       //Destroy objects but retain memory in case x reuses it in the future

include/boost/container/stable_vector.hpp

@@ -597,6 +597,11 @@ class stable_vector
 
    #ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
    private:
+
+   //`allocator_type::value_type` must match container's `value type`. If this
+   //assertion fails, please review your allocator definition. 
+   BOOST_CONTAINER_STATIC_ASSERT((dtl::is_same<value_type, typename allocator_traits<allocator_type>::value_type>::value));
+
    BOOST_COPYABLE_AND_MOVABLE(stable_vector)
    BOOST_STATIC_CONSTEXPR size_type ExtraPointers = index_traits_type::ExtraPointers;
 

include/boost/container/string.hpp

@@ -628,6 +628,11 @@ class basic_string
 
    #ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
    private:
+
+   //`allocator_type::value_type` must match container's `value type`. If this
+   //assertion fails, please review your allocator definition. 
+   BOOST_CONTAINER_STATIC_ASSERT((dtl::is_same<value_type, typename allocator_traits<allocator_type>::value_type>::value));
+
    typedef constant_iterator<CharT> cvalue_iterator;
    typedef typename base_t::alloc_version  alloc_version;
    typedef ::boost::intrusive::pointer_traits<pointer> pointer_traits;

include/boost/container/vector.hpp

@@ -813,8 +813,11 @@ public:
    typedef BOOST_CONTAINER_IMPDEF(boost::container::reverse_iterator<const_iterator>)  const_reverse_iterator;
 
 private:
-
    #ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
+   //`allocator_type::value_type` must match container's `value type`. If this
+   //assertion fails, please review your allocator definition. 
+   BOOST_CONTAINER_STATIC_ASSERT((dtl::is_same<value_type, typename allocator_traits_t::value_type>::value));
+
    typedef typename boost::container::
       allocator_traits<allocator_type>::size_type                             alloc_size_type;
    typedef typename get_vector_opt<Options, alloc_size_type>::type            options_type;