diff --git a/test/Jamfile b/test/Jamfile
index 07a50dd..067cfab 100644
--- a/test/Jamfile
+++ b/test/Jamfile
@@ -306,3 +306,6 @@ run abi_test_main.cpp abi_test_nt : : : : abi_test_mt_nt ;
 
 run abi_test_main.cpp abi_test_mt/<cxxstd>0x : : : <cxxstd>98 : abi_test_03_11 ;
 run abi_test_main.cpp abi_test_mt/<cxxstd>98 : : : <cxxstd>0x : abi_test_11_03 ;
+
+run weak_ptr_alias_test.cpp ;
+run weak_ptr_alias_move_test.cpp ;
diff --git a/test/weak_ptr_alias_move_test.cpp b/test/weak_ptr_alias_move_test.cpp
new file mode 100644
index 0000000..57a7143
--- /dev/null
+++ b/test/weak_ptr_alias_move_test.cpp
@@ -0,0 +1,97 @@
+
+// weak_ptr_alias_move_test.cpp
+//
+// Copyright 2007, 2019 Peter Dimov
+//
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+
+#include <boost/core/lightweight_test.hpp>
+#include <boost/weak_ptr.hpp>
+#include <boost/shared_ptr.hpp>
+#include <boost/config.hpp>
+#include <memory>
+#include <cstddef>
+
+#if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
+
+class incomplete;
+
+struct X
+{
+    int v_;
+
+    explicit X( int v ): v_( v )
+    {
+    }
+
+    ~X()
+    {
+        v_ = 0;
+    }
+};
+
+template<class P1, class P2> bool share_ownership( P1 const& p1, P2 const& p2 )
+{
+    return !p1.owner_before( p2 ) && !p2.owner_before( p1 );
+}
+
+int main()
+{
+    {
+        boost::shared_ptr<float> p( new float );
+        boost::weak_ptr<float> p2( p );
+
+        int m2 = 0;
+        boost::weak_ptr<int const volatile> p3( std::move( p2 ), &m2 );
+
+        BOOST_TEST( p3.use_count() == p.use_count() );
+        BOOST_TEST( share_ownership( p, p3 ) );
+        BOOST_TEST( p3.lock().get() == &m2 );
+
+        BOOST_TEST( p2.empty() );
+    }
+
+    {
+        boost::shared_ptr<incomplete> p;
+        boost::weak_ptr<incomplete> p2( p );
+
+        int m2 = 0;
+        boost::weak_ptr<int const volatile> p3( std::move( p2 ), &m2 );
+
+        BOOST_TEST( p3.use_count() == p.use_count() );
+        BOOST_TEST( share_ownership( p, p3 ) );
+        BOOST_TEST( p3.lock().get() == 0 );
+
+        BOOST_TEST( p2.empty() );
+    }
+
+    {
+        boost::shared_ptr<X> p( new X( 5 ) );
+        boost::weak_ptr<X> p2( p );
+
+        boost::weak_ptr<int const volatile> p3( std::move( p2 ), &p2.lock()->v_ );
+
+        BOOST_TEST( p3.use_count() == p.use_count() );
+        BOOST_TEST( share_ownership( p, p3 ) );
+        BOOST_TEST( p3.lock().get() == &p->v_ );
+
+        BOOST_TEST( p2.empty() );
+
+        p.reset();
+        BOOST_TEST( p3.expired() );
+    }
+
+    return boost::report_errors();
+}
+
+#else // defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
+
+int main()
+{
+    return 0;
+}
+
+#endif
diff --git a/test/weak_ptr_alias_test.cpp b/test/weak_ptr_alias_test.cpp
new file mode 100644
index 0000000..39dd30e
--- /dev/null
+++ b/test/weak_ptr_alias_test.cpp
@@ -0,0 +1,203 @@
+
+// weak_ptr_alias_test.cpp
+//
+// Copyright 2007, 2019 Peter Dimov
+//
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+
+#include <boost/core/lightweight_test.hpp>
+#include <boost/weak_ptr.hpp>
+#include <boost/shared_ptr.hpp>
+#include <memory>
+#include <cstddef>
+
+//
+
+class incomplete;
+
+struct X
+{
+    int v_;
+
+    explicit X( int v ): v_( v )
+    {
+    }
+
+    ~X()
+    {
+        v_ = 0;
+    }
+};
+
+template<class P1, class P2> bool share_ownership( P1 const& p1, P2 const& p2 )
+{
+    return !p1.owner_before( p2 ) && !p2.owner_before( p1 );
+}
+
+int main()
+{
+    {
+        boost::shared_ptr<double> p( new double );
+
+        float m = 0;
+        boost::weak_ptr<float> p2( p, &m );
+
+        BOOST_TEST( p2.use_count() == p.use_count() );
+        BOOST_TEST( share_ownership( p, p2 ) );
+        BOOST_TEST( p2.lock().get() == &m );
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<int> p3( p2, &m2 );
+
+            BOOST_TEST( p3.use_count() == p2.use_count() );
+            BOOST_TEST( share_ownership( p2, p3 ) );
+            BOOST_TEST( p3.lock().get() == &m2 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<int const> p3( p, &m2 );
+
+            BOOST_TEST( p3.use_count() == p.use_count() );
+            BOOST_TEST( share_ownership( p, p3 ) );
+            BOOST_TEST( p3.lock().get() == &m2 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<int volatile> p3( p2, &m2 );
+
+            BOOST_TEST( p3.use_count() == p2.use_count() );
+            BOOST_TEST( share_ownership( p2, p3 ) );
+            BOOST_TEST( p3.lock().get() == &m2 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<void> p3( p, &m2 );
+
+            BOOST_TEST( p3.use_count() == p.use_count() );
+            BOOST_TEST( share_ownership( p, p3 ) );
+            BOOST_TEST( p3.lock().get() == &m2 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<void> p3( p2, &m2 );
+
+            BOOST_TEST( p3.use_count() == p2.use_count() );
+            BOOST_TEST( share_ownership( p2, p3 ) );
+            BOOST_TEST( p3.lock().get() == &m2 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<void const volatile> p3( p, &m2 );
+
+            BOOST_TEST( p3.use_count() == p.use_count() );
+            BOOST_TEST( share_ownership( p, p3 ) );
+            BOOST_TEST( p3.lock().get() == &m2 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<void const volatile> p3( p2, &m2 );
+
+            BOOST_TEST( p3.use_count() == p2.use_count() );
+            BOOST_TEST( share_ownership( p2, p3 ) );
+            BOOST_TEST( p3.lock().get() == &m2 );
+        }
+    }
+
+    {
+        boost::shared_ptr<incomplete> p;
+
+        float m = 0;
+        boost::weak_ptr<float> p2( p, &m );
+
+        BOOST_TEST( p2.use_count() == p.use_count() );
+        BOOST_TEST( share_ownership( p, p2 ) );
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<int> p3( p2, &m2 );
+
+            BOOST_TEST( p3.use_count() == p2.use_count() );
+            BOOST_TEST( share_ownership( p2, p3 ) );
+            BOOST_TEST( p3.lock().get() == 0 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<int const> p3( p, &m2 );
+
+            BOOST_TEST( p3.use_count() == p.use_count() );
+            BOOST_TEST( share_ownership( p, p3 ) );
+            BOOST_TEST( p3.lock().get() == 0 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<int volatile> p3( p2, &m2 );
+
+            BOOST_TEST( p3.use_count() == p2.use_count() );
+            BOOST_TEST( share_ownership( p2, p3 ) );
+            BOOST_TEST( p3.lock().get() == 0 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<void> p3( p, &m2 );
+
+            BOOST_TEST( p3.use_count() == p.use_count() );
+            BOOST_TEST( share_ownership( p, p3 ) );
+            BOOST_TEST( p3.lock().get() == 0 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<void> p3( p2, &m2 );
+
+            BOOST_TEST( p3.use_count() == p2.use_count() );
+            BOOST_TEST( share_ownership( p2, p3 ) );
+            BOOST_TEST( p3.lock().get() == 0 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<void const volatile> p3( p, &m2 );
+
+            BOOST_TEST( p3.use_count() == p.use_count() );
+            BOOST_TEST( share_ownership( p, p3 ) );
+            BOOST_TEST( p3.lock().get() == 0 );
+        }
+
+        {
+            int m2 = 0;
+            boost::weak_ptr<void const volatile> p3( p2, &m2 );
+
+            BOOST_TEST( p3.use_count() == p2.use_count() );
+            BOOST_TEST( share_ownership( p2, p3 ) );
+            BOOST_TEST( p3.lock().get() == 0 );
+        }
+    }
+
+    {
+        boost::shared_ptr<X> p( new X( 5 ) );
+
+        boost::weak_ptr<int const> p2( p, &p->v_ );
+
+        BOOST_TEST( p2.use_count() == p.use_count() );
+        BOOST_TEST( share_ownership( p, p2 ) );
+        BOOST_TEST( p2.lock().get() == &p->v_ );
+
+        p.reset();
+        BOOST_TEST( p2.expired() );
+    }
+
+    return boost::report_errors();
+}