Fixes #292 ("Forward declarations of std types cause compilation errors on some platforms")

Author: igaztanaga

doc/move.qbk

@@ -802,6 +802,15 @@ Special thanks to:
 
 [section:release_notes Release Notes]
 
+[section:release_notes_boost_1_87 Boost 1.87 Release]
+
+*  Fixed bugs:
+   *  [@https://github.com/boostorg/move/issues/292 Git Issue #292: ['"Forward declarations of std types cause compilation errors on some platforms"]].
+
+[endsect]
+
+Forward declarations of std types cause compilation errors on some platforms #292
+
 [section:release_notes_boost_1_85 Boost 1.85 Release]
 
 *  Fixed bugs:

include/boost/move/detail/std_ns_begin.hpp

@@ -23,12 +23,12 @@
 #elif defined(BOOST_GNU_STDLIB) && defined(_GLIBCXX_BEGIN_NAMESPACE)  //GCC >= 4.2
    #define BOOST_MOVE_STD_NS_BEG _GLIBCXX_BEGIN_NAMESPACE(std)
    #define BOOST_MOVE_STD_NS_END _GLIBCXX_END_NAMESPACE
-#else
-   #if defined(_MSC_VER) && (_MSC_VER >= 1915)
-      #pragma warning (push)
-      #pragma warning (disable : 4643) // Forward declaring 'X' in namespace std is not permitted by the C++ Standard
-   #endif
+#elif defined(BOOST_DINKUMWARE_STDLIB)
+   #define BOOST_MOVE_STD_NS_BEG _STD_BEGIN
+   #define BOOST_MOVE_STD_NS_END _STD_END
+#endif
 
-   #define BOOST_MOVE_STD_NS_BEG namespace std{
-   #define BOOST_MOVE_STD_NS_END }
+#if defined(_MSC_VER) && (_MSC_VER >= 1915)
+   #pragma warning (push)
+   #pragma warning (disable : 4643) // Forward declaring 'X' in namespace std is not permitted by the C++ Standard
 #endif

include/boost/move/detail/std_ns_end.hpp

@@ -14,3 +14,6 @@
 #elif defined(_MSC_VER) && (_MSC_VER >= 1915)
    #pragma warning (pop)
 #endif   //BOOST_MOVE_STD_NS_GCC_DIAGNOSTIC_PUSH
+
+#undef BOOST_MOVE_STD_NS_BEG
+#undef BOOST_MOVE_STD_NS_END