Implement LWG#2855 - made easy by previous refactoring

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@300218 91177308-0d34-0410-b5e6-96231b3b80d8

include/exception

@@ -243,8 +243,8 @@ throw_with_nested (_Tp& __t)
 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 {
 #ifndef _LIBCPP_NO_EXCEPTIONS
-    typedef typename remove_reference<_Tp>::type _Up;
-//    static_assert( is_copy_constructible<_Up>::value, "");
+    typedef typename decay<_Tp>::type _Up;
+    static_assert( is_copy_constructible<_Up>::value, "type thrown must be CopyConstructible");
     __throw_with_nested<_Tp, _Up,
         is_class<_Up>::value &&
         !is_base_of<nested_exception, _Up>::value &&

test/std/language.support/support.exception/except.nested/throw_with_nested.pass.cpp

@@ -107,6 +107,16 @@ int main()
             assert(i == 7);
         }
     }
+    {
+        try
+        {
+            std::throw_with_nested("String literal");
+            assert(false);
+        }
+        catch (const char * s)
+        {
+        }
+    }
 #if TEST_STD_VER > 11
     {
         try

www/cxx1z_status.html

@@ -463,7 +463,7 @@
 	<tr><td><a href="http://wg21.link/LWG2842">2842</a></td><td>in_place_t check for optional::optional(U&amp;&amp;) should decay U</td><td>Kona</td><td>Complete</td></tr>
 	<tr><td><a href="http://wg21.link/LWG2850">2850</a></td><td>std::function move constructor does unnecessary work</td><td>Kona</td><td></td></tr>
 	<tr><td><a href="http://wg21.link/LWG2853">2853</a></td><td>Possible inconsistency in specification of erase in [vector.modifiers]</td><td>Kona</td><td></td></tr>
-	<tr><td><a href="http://wg21.link/LWG2855">2855</a></td><td>std::throw_with_nested("string_literal")</td><td>Kona</td><td></td></tr>
+	<tr><td><a href="http://wg21.link/LWG2855">2855</a></td><td>std::throw_with_nested("string_literal")</td><td>Kona</td><td>Complete</td></tr>
 	<tr><td><a href="http://wg21.link/LWG2857">2857</a></td><td>{variant,optional,any}::emplace should return the constructed value</td><td>Kona</td><td></td></tr>
 	<tr><td><a href="http://wg21.link/LWG2861">2861</a></td><td>basic_string should require that charT match traits::char_type</td><td>Kona</td><td>Complete</td></tr>
 	<tr><td><a href="http://wg21.link/LWG2866">2866</a></td><td>Incorrect derived classes constraints</td><td>Kona</td><td></td></tr>
@@ -489,7 +489,7 @@
 <!-- 	<tr><td></td><td></td><td></td><td></td></tr> -->
   </table>
 
-  <p>Last Updated: 11-Apr-2017</p>
+  <p>Last Updated: 13-Apr-2017</p>
 </div>
 </body>
 </html>