re PR libstdc++/68139 (rethrow_if_nested should tolerate overloaded unary operator&)

PR libstdc++/68139

From-SVN: r231562

libstdc++-v3/ChangeLog

+2015-12-11  Ville Voutilainen  <ville.voutilainen@gmail.com>
+
+	PR libstdc++/68139
+
+	* libsupc++/nested_exception.h (_S_rethrow): Use std::__addressof.
+	* testsuite/18_support/nested_exception/68139.cc: New.
+
 2015-12-10  Jonathan Wakely  <jwakely@redhat.com>
 
 	* testsuite/experimental/memory/shared_ptr/assign/assign.cc: Replace

libstdc++-v3/libsupc++/nested_exception.h

@@ -37,6 +37,7 @@
 #else
 
 #include <bits/c++config.h>
+#include <bits/move.h>
 
 #if ATOMIC_INT_LOCK_FREE < 2
 #  error This platform does not support exception propagation.
@@ -142,7 +143,8 @@ namespace std
     {
       static void _S_rethrow(const _Tp& __t)
       {
-	if (auto __tp = dynamic_cast<const nested_exception*>(&__t))
+	if (auto __tp =
+            dynamic_cast<const nested_exception*>(std::__addressof(__t)))
 	  __tp->rethrow_nested();
       }
     };

libstdc++-v3/testsuite/18_support/nested_exception/68139.cc

+// { dg-do compile }
+// { dg-options "-std=gnu++11" }
+// { dg-require-atomic-builtins "" }
+
+// Copyright (C) 2015 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <exception>
+
+// libstdc++/68139
+struct C {
+    virtual ~C(){}
+    void operator&() const = delete;
+};
+
+int main() { std::rethrow_if_nested(C()); }
+