From 5595622c3eb401dd4d8aa5fab8e888f7edf873d5 Mon Sep 17 00:00:00 2001
From: Peter Dimov <pdimov@pdimov.com>
Date: Sat, 10 Sep 2016 20:18:37 +0300
Subject: [PATCH] Relax dynamic_cast check; rephrase const_cast test to be more
 MSVC-friendly.

---
 include/boost/pointer_cast.hpp | 19 ++----------------
 test/pointer_cast_test2.cpp    | 36 +++++++++++-----------------------
 2 files changed, 13 insertions(+), 42 deletions(-)

diff --git a/include/boost/pointer_cast.hpp b/include/boost/pointer_cast.hpp
index 7e04512..5af4971 100644
--- a/include/boost/pointer_cast.hpp
+++ b/include/boost/pointer_cast.hpp
@@ -46,27 +46,12 @@ inline T* reinterpret_pointer_cast(U *ptr)
 
 #if !defined( BOOST_NO_CXX11_SMART_PTR )
 
-#include <boost/static_assert.hpp>
-
-#include <boost/type_traits/is_base_of.hpp>
-#include <boost/type_traits/is_pod.hpp>
 #include <boost/type_traits/has_virtual_destructor.hpp>
-
+#include <boost/static_assert.hpp>
 #include <memory>
 
 namespace boost {
 
-namespace detail {
-
-template<class T, class U>
-void assert_safe_moving_upcast() {
-   BOOST_STATIC_ASSERT_MSG( !(boost::is_base_of<T, U>::value && !boost::is_pod<U>::value && !boost::has_virtual_destructor<T>::value)
-     , "Upcast from a non-POD child to a base without virtual destructor is unsafe, because the child's destructor "
-       "will not be called when the base pointer is deleted. Consider using shared_ptr for such types.");
-}
-
-}
-
 //static_pointer_cast overload for std::shared_ptr
 using std::static_pointer_cast;
 
@@ -102,7 +87,7 @@ template<class T, class U> std::unique_ptr<T> dynamic_pointer_cast( std::unique_
 {
     (void) dynamic_cast< T* >( static_cast< U* >( 0 ) );
 
-    detail::assert_safe_moving_upcast<T, U>();
+    BOOST_STATIC_ASSERT_MSG( boost::has_virtual_destructor<T>::value, "The target of dynamic_pointer_cast must have a virtual destructor." );
 
     T * p = dynamic_cast<T*>( r.get() );
     if( p ) r.release();
diff --git a/test/pointer_cast_test2.cpp b/test/pointer_cast_test2.cpp
index b8575b4..eb28a5d 100644
--- a/test/pointer_cast_test2.cpp
+++ b/test/pointer_cast_test2.cpp
@@ -94,16 +94,6 @@ static void test_static_cast()
 
 static void test_const_cast()
 {
-    {
-        std::unique_ptr<int const> p1( new int );
-        int const * q1 = p1.get();
-
-        std::unique_ptr<int> p2 = boost::const_pointer_cast<int>( std::move( p1 ) );
-
-        BOOST_TEST( p1.get() == 0 );
-        BOOST_TEST_EQ( p2.get(), q1 );
-    }
-
     {
         std::unique_ptr<int> p1( new int );
         int * q1 = p1.get();
@@ -112,22 +102,13 @@ static void test_const_cast()
 
         BOOST_TEST( p1.get() == 0 );
         BOOST_TEST_EQ( p2.get(), q1 );
+
+        std::unique_ptr<int> p3 = boost::const_pointer_cast<int>( std::move( p2 ) );
+
+        BOOST_TEST( p2.get() == 0 );
+        BOOST_TEST_EQ( p3.get(), q1 );
     }
 
-#if !defined( BOOST_MSVC ) || BOOST_MSVC >= 1900
-
-    {
-        std::unique_ptr<int const[]> p1( new int[ 1 ] );
-        int const * q1 = p1.get();
-
-        std::unique_ptr<int[]> p2 = boost::const_pointer_cast<int[]>( std::move( p1 ) );
-
-        BOOST_TEST( p1.get() == 0 );
-        BOOST_TEST_EQ( p2.get(), q1 );
-    }
-
-#endif
-
     {
         std::unique_ptr<int[]> p1( new int[ 1 ] );
         int * q1 = p1.get();
@@ -136,7 +117,12 @@ static void test_const_cast()
 
         BOOST_TEST( p1.get() == 0 );
         BOOST_TEST_EQ( p2.get(), q1 );
-    }
+
+        std::unique_ptr<int[]> p3 = boost::const_pointer_cast<int[]>( std::move( p2 ) );
+
+        BOOST_TEST( p2.get() == 0 );
+        BOOST_TEST_EQ( p3.get(), q1 );
+	}
 }
 
 struct B2