1 files changed, 30 insertions, 5 deletions
diff --git a/boost/sort/spreadsort/spreadsort.hpp b/boost/sort/spreadsort/spreadsort.hpp
index 678fba44f1..48377123e3 100644
--- a/boost/sort/spreadsort/spreadsort.hpp
+++ b/boost/sort/spreadsort/spreadsort.hpp
@@ -88,8 +88,8 @@ namespace spreadsort {
   }
 
   /*!
-    \brief  Generic @c spreadsort variant detecting string element type so call to @c string_sort for @c std::strings and @c std::wstrings.
-    \details If the data type provided is a string or wstring, @c string_sort is used.
+    \brief  Generic @c spreadsort variant detecting string element type so call to @c string_sort for @c std::strings.
+    \details If the data type provided is a string, @c string_sort is used.
     \note Sorting other data types requires picking between @c integer_sort, @c float_sort and @c string_sort directly,
     as @c spreadsort won't accept types that don't have the appropriate @c type_traits.
 
@@ -107,13 +107,38 @@ namespace spreadsort {
   template <class RandomAccessIter>
   inline typename boost::enable_if_c<
     is_same<typename std::iterator_traits<RandomAccessIter>::value_type,
-            typename std::string>::value ||
-    is_same<typename std::iterator_traits<RandomAccessIter>::value_type,
-            typename std::wstring>::value, void >::type
+            typename std::string>::value, void >::type
   spreadsort(RandomAccessIter first, RandomAccessIter last)
   {
     string_sort(first, last);
   }
+
+  /*!
+    \brief  Generic @c spreadsort variant detecting string element type so call to @c string_sort for @c std::wstrings.
+    \details If the data type provided is a wstring, @c string_sort is used.
+    \note Sorting other data types requires picking between @c integer_sort, @c float_sort and @c string_sort directly,
+    as @c spreadsort won't accept types that don't have the appropriate @c type_traits.  Also, 2-byte wide-characters are the limit above which string_sort is inefficient, so on platforms with wider characters, this will not accept wstrings.
+
+    \param[in] first Iterator pointer to first element.
+    \param[in] last Iterator pointing to one beyond the end of data.
+
+    \pre [@c first, @c last) is a valid range.
+    \pre @c RandomAccessIter @c value_type is mutable.
+    \pre @c RandomAccessIter @c value_type is <a href="http://en.cppreference.com/w/cpp/concept/LessThanComparable">LessThanComparable</a>
+    \pre @c RandomAccessIter @c value_type supports the @c operator>>,
+    which returns an integer-type right-shifted a specified number of bits.
+    \post The elements in the range [@c first, @c last) are sorted in ascending order.
+  */
+  template <class RandomAccessIter>
+  inline typename boost::enable_if_c<
+    is_same<typename std::iterator_traits<RandomAccessIter>::value_type,
+            typename std::wstring>::value &&
+    sizeof(wchar_t) == 2, void >::type
+  spreadsort(RandomAccessIter first, RandomAccessIter last)
+  {
+    boost::uint16_t unused = 0;
+    string_sort(first, last, unused);
+  }
 } // namespace spreadsort
 } // namespace sort
 } // namespace boost