[Boost-commit] svn:boost r76509 - branches/release/boost/move

Subject: [Boost-commit] svn:boost r76509 - branches/release/boost/move
From: igaztanaga_at_[hidden]
Date: 2012-01-15 07:25:13

Author: igaztanaga
Date: 2012-01-15 07:25:12 EST (Sun, 15 Jan 2012)
New Revision: 76509
URL: http://svn.boost.org/trac/boost/changeset/76509

Log:
Ticket #6396: Implicit instanciation of boost::rv for non-cass types generates an error
Text files modified: 
   branches/release/boost/move/move.hpp |    23 ++++++++++++++++++++++-                 
   1 files changed, 22 insertions(+), 1 deletions(-)

Modified: branches/release/boost/move/move.hpp
==============================================================================
--- branches/release/boost/move/move.hpp	(original)
+++ branches/release/boost/move/move.hpp	2012-01-15 07:25:12 EST (Sun, 15 Jan 2012)
@@ -225,13 +225,32 @@
 
    namespace boost {
 
+   namespace move_detail {
+      template<class T>
+      struct is_class_or_union
+      {
+         struct twochar { char _[2]; };
+         template <class U>
+         static char is_class_or_union_tester(void(U::*)(void));
+         template <class U>
+         static twochar is_class_or_union_tester(...);
+         static const bool value = sizeof(is_class_or_union_tester<T>(0)) == sizeof(char);
+      };
+      struct empty{};
+   }
+
    //////////////////////////////////////////////////////////////////////////////
    //
    //                            struct rv
    //
    //////////////////////////////////////////////////////////////////////////////
    template <class T>
-   class rv : public T
+   class rv
+      : public BOOST_MOVE_MPL_NS::if_c
+         < ::boost::move_detail::is_class_or_union<T>::value
+         , T
+         , ::boost::move_detail::empty
+         >::type
    {
       rv();
       ~rv();
@@ -239,6 +258,8 @@
       void operator=(rv const&);
    } BOOST_MOVE_ATTRIBUTE_MAY_ALIAS;
 
+
+
    //////////////////////////////////////////////////////////////////////////////
    //
    //                            move_detail::is_rv