Split g++ 8 Travis job, because log length

.travis.yml

@@ -107,7 +107,17 @@ matrix:
 
     - os: linux
       compiler: g++-8
-      env: TOOLSET=gcc COMPILER=g++-8 CXXSTD=03,11,14,17,2a
+      env: TOOLSET=gcc COMPILER=g++-8 CXXSTD=03,11,14
+      addons:
+        apt:
+          packages:
+            - g++-8
+          sources:
+            - ubuntu-toolchain-r-test
+
+    - os: linux
+      compiler: g++-8
+      env: TOOLSET=gcc COMPILER=g++-8 CXXSTD=17,2a
       addons:
         apt:
           packages:

appveyor.yml

@@ -20,7 +20,7 @@ environment:
       TOOLSET: msvc-12.0,msvc-14.0
       ADDRMD: 32,64
     - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
-      TOOLSET: msvc-14.1
+      TOOLSET: msvc-14.1,clang-win
       CXXSTD: 14,17
       ADDRMD: 32,64
     - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015

doc/smart_ptr.adoc

@@ -19,6 +19,8 @@ Greg Colvin, Beman Dawes, Peter Dimov, Glen Fernandes
 
 include::smart_ptr/introduction.adoc[]
 
+include::smart_ptr/changelog.adoc[]
+
 include::smart_ptr/scoped_ptr.adoc[]
 
 include::smart_ptr/scoped_array.adoc[]

doc/smart_ptr/changelog.adoc

@@ -0,0 +1,19 @@
+////
+Copyright 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
+////
+
+[#changelog]
+# Revision History
+:toc:
+:toc-title:
+:idprefix: changelog_
+
+## Changes in 1.71.0
+
+* Added aliasing constructors to `weak_ptr`
+* Added `weak_ptr<T>::empty()`

doc/smart_ptr/introduction.adoc

@@ -11,7 +11,9 @@ http://www.boost.org/LICENSE_1_0.txt
 
 [#introduction]
 # Introduction
-:idprefix: intro
+:toc:
+:toc-title:
+:idprefix: intro_
 
 Smart pointers are objects which store pointers to dynamically allocated (heap) objects.
 They behave much like built-in {cpp} pointers except that they automatically delete the object

doc/smart_ptr/intrusive_ptr.adoc

@@ -77,7 +77,7 @@ namespace boost {
 
     explicit operator bool () const noexcept;
 
-    void swap(intrusive_ptr & b) noexept;
+    void swap(intrusive_ptr & b) noexcept;
   };
 
   template<class T, class U>

doc/smart_ptr/shared_ptr.adoc

@@ -132,7 +132,6 @@ namespace boost {
     template<class Y> shared_ptr(shared_ptr<Y> && r) noexcept;
 
     template<class Y> shared_ptr(shared_ptr<Y> const & r, element_type * p) noexcept;
-
     template<class Y> shared_ptr(shared_ptr<Y> && r, element_type * p) noexcept;
 
     template<class Y> explicit shared_ptr(weak_ptr<Y> const & r);
@@ -373,7 +372,7 @@ template<class Y> shared_ptr(shared_ptr<Y> const & r, element_type * p) noexcept
 [none]
 * {blank}
 +
-Effects:: constructs a `shared_ptr` that shares ownership with `r` and stores `p`.
+Effects:: Copy-constructs a `shared_ptr` from `r`, while storing `p` instead.
 
 Postconditions:: `get() == p && use_count() == r.use_count()`.
 

doc/smart_ptr/weak_ptr.adoc

@@ -88,6 +88,10 @@ namespace boost {
 
     weak_ptr(weak_ptr && r) noexcept;
 
+    template<class Y> weak_ptr(shared_ptr<Y> const & r, element_type * p) noexcept;
+    template<class Y> weak_ptr(weak_ptr<Y> const & r, element_type * p) noexcept;
+    template<class Y> weak_ptr(weak_ptr<Y> && r, element_type * p) noexcept;
+
     ~weak_ptr() noexcept;
 
     weak_ptr & operator=(weak_ptr const & r) noexcept;
@@ -98,6 +102,8 @@ namespace boost {
     long use_count() const noexcept;
     bool expired() const noexcept;
 
+    bool empty() const noexcept;
+
     shared_ptr<T> lock() const noexcept;
 
     void reset() noexcept;
@@ -157,6 +163,21 @@ weak_ptr(weak_ptr && r) noexcept;
 Effects:: Constructs a `weak_ptr` that has the value `r` held.
 Postconditions:: `r` is empty.
 
+### aliasing constructors
+```
+template<class Y> weak_ptr(shared_ptr<Y> const & r, element_type * p) noexcept;
+```
+```
+template<class Y> weak_ptr(weak_ptr<Y> const & r, element_type * p) noexcept;
+```
+```
+template<class Y> weak_ptr(weak_ptr<Y> && r, element_type * p) noexcept;
+```
+Effects:: Constructs a `weak_ptr` from `r` as if by using the corresponding converting/copy/move constructor, but stores `p` instead.
+Postconditions:: `use_count() == r.use_count()`. When `!expired()`, `shared_ptr<T>(*this).get() == p`.
+
+NOTE: These constructors are an extension, not present in `std::weak_ptr`.
+
 ### destructor
 ```
 ~weak_ptr() noexcept;
@@ -204,6 +225,17 @@ bool expired() const noexcept;
 +
 Returns:: `use_count() == 0`.
 
+### empty
+```
+bool empty() const noexcept;
+```
+[none]
+* {blank}
++
+Returns:: `true` when `*this` is empty, `false` otherwise.
+
+NOTE: This function is an extension, not present in `std::weak_ptr`.
+
 ### lock
 ```
 shared_ptr<T> lock() const noexcept;

include/boost/smart_ptr/atomic_shared_ptr.hpp

@@ -63,6 +63,11 @@ public:
     {
     }
 
+    atomic_shared_ptr( shared_ptr<T> p ) BOOST_SP_NOEXCEPT
+        : p_( std::move( p ) ), l_ BOOST_DETAIL_SPINLOCK_INIT
+    {
+    }
+
 #else
 
     atomic_shared_ptr() BOOST_SP_NOEXCEPT
@@ -71,8 +76,6 @@ public:
         std::memcpy( &l_, &init, sizeof( init ) );
     }
 
-#endif
-
     atomic_shared_ptr( shared_ptr<T> p ) BOOST_SP_NOEXCEPT
 #if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
         : p_( std::move( p ) )
@@ -84,6 +87,8 @@ public:
         std::memcpy( &l_, &init, sizeof( init ) );
     }
 
+#endif
+
     atomic_shared_ptr& operator=( shared_ptr<T> r ) BOOST_SP_NOEXCEPT
     {
         boost::detail::spinlock::scoped_lock lock( l_ );

include/boost/smart_ptr/enable_shared_from_raw.hpp

@@ -144,8 +144,7 @@ template<typename T>
 boost::weak_ptr<T> weak_from_raw(T *p)
 {
     BOOST_ASSERT(p != 0);
-    boost::weak_ptr<T> result;
-    result._internal_aliasing_assign(p->enable_shared_from_raw::weak_from_this(), p);
+    boost::weak_ptr<T> result(p->enable_shared_from_raw::weak_from_this(), p);
     return result;
 }
 

include/boost/smart_ptr/intrusive_ptr.hpp

@@ -297,6 +297,8 @@ template<class T> T * get_pointer(intrusive_ptr<T> const & p) BOOST_SP_NOEXCEPT
     return p.get();
 }
 
+// pointer casts
+
 template<class T, class U> intrusive_ptr<T> static_pointer_cast(intrusive_ptr<U> const & p)
 {
     return static_cast<T *>(p.get());
@@ -312,6 +314,31 @@ template<class T, class U> intrusive_ptr<T> dynamic_pointer_cast(intrusive_ptr<U
     return dynamic_cast<T *>(p.get());
 }
 
+#if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
+
+template<class T, class U> intrusive_ptr<T> static_pointer_cast( intrusive_ptr<U> && p ) BOOST_SP_NOEXCEPT
+{
+    return intrusive_ptr<T>( static_cast<T*>( p.detach() ), false );
+}
+
+template<class T, class U> intrusive_ptr<T> const_pointer_cast( intrusive_ptr<U> && p ) BOOST_SP_NOEXCEPT
+{
+    return intrusive_ptr<T>( const_cast<T*>( p.detach() ), false );
+}
+
+template<class T, class U> intrusive_ptr<T> dynamic_pointer_cast( intrusive_ptr<U> && p ) BOOST_SP_NOEXCEPT
+{
+    T * p2 = dynamic_cast<T*>( p.get() );
+
+    intrusive_ptr<T> r( p2, false );
+
+    if( p2 ) p.detach();
+
+    return r;
+}
+
+#endif // defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
+
 // operator<<
 
 #if !defined(BOOST_NO_IOSTREAM)

include/boost/smart_ptr/weak_ptr.hpp

@@ -137,6 +137,23 @@ public:
         boost::detail::sp_assert_convertible< Y, T >();
     }
 
+    // aliasing
+    template<class Y> weak_ptr(shared_ptr<Y> const & r, element_type * p) BOOST_SP_NOEXCEPT: px( p ), pn( r.pn )
+    {
+    }
+
+    template<class Y> weak_ptr(weak_ptr<Y> const & r, element_type * p) BOOST_SP_NOEXCEPT: px( p ), pn( r.pn )
+    {
+    }
+
+#if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
+
+    template<class Y> weak_ptr(weak_ptr<Y> && r, element_type * p) BOOST_SP_NOEXCEPT: px( p ), pn( std::move( r.pn ) )
+    {
+    }
+
+#endif
+
 #if !defined(BOOST_MSVC) || (BOOST_MSVC >= 1300)
 
     template<class Y>
@@ -194,6 +211,11 @@ public:
         return pn.empty();
     }
 
+    bool empty() const BOOST_SP_NOEXCEPT // extension, not in std::weak_ptr
+    {
+        return pn.empty();
+    }
+
     void reset() BOOST_SP_NOEXCEPT
     {
         this_type().swap(*this);
@@ -205,13 +227,6 @@ public:
         pn.swap(other.pn);
     }
 
-    template<typename Y>
-    void _internal_aliasing_assign(weak_ptr<Y> const & r, element_type * px2) BOOST_SP_NOEXCEPT
-    {
-        px = px2;
-        pn = r.pn;
-    }
-
     template<class Y> bool owner_before( weak_ptr<Y> const & rhs ) const BOOST_SP_NOEXCEPT
     {
         return pn < rhs.pn;

test/Jamfile

@@ -158,18 +158,18 @@ compile-fail array_fail_dereference.cpp ;
 compile-fail array_fail_member_access.cpp ;
 compile-fail array_fail_array_access.cpp ;
 
-run make_shared_array_test.cpp ;
+run make_shared_array_test.cpp : : : <toolset>msvc-8.0:<build>no ;
 run make_shared_arrays_test.cpp ; # <cxxflags>-fno-deduce-init-list no longer needed for gcc-4.6
-run make_shared_array_throws_test.cpp ;
-run make_shared_array_esft_test.cpp ;
-run make_shared_array_noinit_test.cpp ;
-run make_shared_array_value_test.cpp ;
+run make_shared_array_throws_test.cpp : : : <toolset>msvc-8.0:<build>no ;
+run make_shared_array_esft_test.cpp : : : <toolset>msvc-8.0:<build>no ;
+run make_shared_array_noinit_test.cpp : : : <toolset>msvc-8.0:<build>no ;
+run make_shared_array_value_test.cpp : : : <toolset>msvc-8.0:<build>no ;
 run allocate_shared_array_test.cpp ;
 run allocate_shared_arrays_test.cpp ; # <cxxflags>-fno-deduce-init-list no longer needed for gcc-4.6
-run allocate_shared_array_throws_test.cpp ;
-run allocate_shared_array_esft_test.cpp ;
-run allocate_shared_array_noinit_test.cpp ;
-run allocate_shared_array_value_test.cpp ;
+run allocate_shared_array_throws_test.cpp : : : <toolset>msvc-8.0:<build>no ;
+run allocate_shared_array_esft_test.cpp : : : <toolset>msvc-8.0:<build>no ;
+run allocate_shared_array_noinit_test.cpp : : : <toolset>msvc-8.0:<build>no ;
+run allocate_shared_array_value_test.cpp : : : <toolset>msvc-8.0:<build>no ;
 run allocate_shared_array_construct_test.cpp ;
 
 run make_unique_test.cpp ;
@@ -236,7 +236,7 @@ run shared_ptr_fn_test.cpp ;
 run get_deleter_test2.cpp ;
 run get_deleter_test3.cpp ;
 run get_deleter_array_test2.cpp ;
-run get_deleter_array_test3.cpp ;
+run get_deleter_array_test3.cpp : : : <toolset>msvc-8.0:<build>no ;
 
 run sp_convertible_test2.cpp ;
 
@@ -275,7 +275,7 @@ run local_sp_fn_test.cpp ;
 run lsp_convertible_test.cpp ;
 run lsp_convertible_test2.cpp ;
 
-run make_shared_array_tmp_test.cpp ;
+run make_shared_array_tmp_test.cpp : : : <toolset>msvc-8.0:<build>no ;
 
 run lw_thread_test.cpp : : : <threading>multi ;
 
@@ -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 ;

test/intrusive_ptr_move_test.cpp

@@ -41,7 +41,7 @@ class base
 {
 private:
 
-    boost::detail::atomic_count use_count_;
+    mutable boost::detail::atomic_count use_count_;
 
     base(base const &);
     base & operator=(base const &);
@@ -69,24 +69,24 @@ public:
 
 #if !defined(BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP)
 
-    inline friend void intrusive_ptr_add_ref(base * p)
+    inline friend void intrusive_ptr_add_ref(base const * p)
     {
         ++p->use_count_;
     }
 
-    inline friend void intrusive_ptr_release(base * p)
+    inline friend void intrusive_ptr_release(base const * p)
     {
         if(--p->use_count_ == 0) delete p;
     }
 
 #else
 
-    void add_ref()
+    void add_ref() const
     {
         ++use_count_;
     }
 
-    void release()
+    void release() const
     {
         if(--use_count_ == 0) delete this;
     }
@@ -103,12 +103,12 @@ long base::instances = 0;
 namespace boost
 {
 
-inline void intrusive_ptr_add_ref(N::base * p)
+inline void intrusive_ptr_add_ref(N::base const * p)
 {
     p->add_ref();
 }
 
-inline void intrusive_ptr_release(N::base * p)
+inline void intrusive_ptr_release(N::base const * p)
 {
     p->release();
 }
@@ -209,6 +209,58 @@ int main()
         BOOST_TEST( N::base::instances == 0 );
     }
 
+    {
+        boost::intrusive_ptr<X> px( new Y );
+
+        X * px2 = px.get();
+
+        boost::intrusive_ptr<Y> py = boost::static_pointer_cast<Y>( std::move( px ) );
+        BOOST_TEST( py.get() == px2 );
+        BOOST_TEST( px.get() == 0 );
+        BOOST_TEST( py->use_count() == 1 );
+    }
+
+    BOOST_TEST( N::base::instances == 0 );
+
+    {
+        boost::intrusive_ptr<X const> px( new X );
+
+        X const * px2 = px.get();
+
+        boost::intrusive_ptr<X> px3 = boost::const_pointer_cast<X>( std::move( px ) );
+        BOOST_TEST( px3.get() == px2 );
+        BOOST_TEST( px.get() == 0 );
+        BOOST_TEST( px3->use_count() == 1 );
+    }
+
+    BOOST_TEST( N::base::instances == 0 );
+
+    {
+        boost::intrusive_ptr<X> px( new Y );
+
+        X * px2 = px.get();
+
+        boost::intrusive_ptr<Y> py = boost::dynamic_pointer_cast<Y>( std::move( px ) );
+        BOOST_TEST( py.get() == px2 );
+        BOOST_TEST( px.get() == 0 );
+        BOOST_TEST( py->use_count() == 1 );
+    }
+
+    BOOST_TEST( N::base::instances == 0 );
+
+    {
+        boost::intrusive_ptr<X> px( new X );
+
+        X * px2 = px.get();
+
+        boost::intrusive_ptr<Y> py = boost::dynamic_pointer_cast<Y>( std::move( px ) );
+        BOOST_TEST( py.get() == 0 );
+        BOOST_TEST( px.get() == px2 );
+        BOOST_TEST( px->use_count() == 1 );
+    }
+
+    BOOST_TEST( N::base::instances == 0 );
+
     return boost::report_errors();
 }
 

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

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();
+}