From a43fe9651b8698eccc56c71f395cd3be34cb1a15 Mon Sep 17 00:00:00 2001
From: redi <redi@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Tue, 21 May 2013 08:15:13 +0000
Subject: [PATCH] 	PR libstdc++/57336 	* include/std/functional
 (__invoke): Do not form function types with 	abstract return type. 	*
 testsuite/20_util/reference_wrapper/invoke-3.cc: New.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@199136 138bc75d-0d04-0410-961f-82ee72b054a4
---
 libstdc++-v3/ChangeLog                             |  7 ++++
 libstdc++-v3/include/std/functional                |  2 +-
 .../20_util/reference_wrapper/invoke-3.cc          | 37 ++++++++++++++++++++++
 3 files changed, 45 insertions(+), 1 deletion(-)
 create mode 100644 libstdc++-v3/testsuite/20_util/reference_wrapper/invoke-3.cc

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 3c1e7a97906..d46fbcf0488 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,10 @@
+2013-05-21  Jonathan Wakely  <jwakely.gcc@gmail.com>
+
+	PR libstdc++/57336
+	* include/std/functional (__invoke): Do not form function types with
+	abstract return type.
+	* testsuite/20_util/reference_wrapper/invoke-3.cc: New.
+
 2013-05-19  Jonathan Wakely  <jwakely.gcc@gmail.com>
 
 	* include/std/tuple (get): Implement N3670.
diff --git a/libstdc++-v3/include/std/functional b/libstdc++-v3/include/std/functional
index 44d3fd508d5..63ba77793fd 100644
--- a/libstdc++-v3/include/std/functional
+++ b/libstdc++-v3/include/std/functional
@@ -195,7 +195,7 @@ _GLIBCXX_HAS_NESTED_TYPE(result_type)
 	     (!is_member_pointer<_Functor>::value
 	      && !is_function<_Functor>::value
 	      && !is_function<typename remove_pointer<_Functor>::type>::value),
-	     typename result_of<_Functor(_Args&&...)>::type
+	     typename result_of<_Functor&(_Args&&...)>::type
 	   >::type
     __invoke(_Functor& __f, _Args&&... __args)
     {
diff --git a/libstdc++-v3/testsuite/20_util/reference_wrapper/invoke-3.cc b/libstdc++-v3/testsuite/20_util/reference_wrapper/invoke-3.cc
new file mode 100644
index 00000000000..4291a672e2a
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/reference_wrapper/invoke-3.cc
@@ -0,0 +1,37 @@
+// { dg-options "-std=gnu++11" }
+// { dg-do compile }
+
+// Copyright (C) 2013 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/>.
+
+// 20.8.3.4 reference_wrapper invocation [refwrap.invoke]
+#include <functional>
+
+struct ABC
+{
+    virtual bool operator()() const = 0;
+};
+
+struct Concrete : ABC
+{
+    virtual bool operator()() const { return true; }
+};
+
+Concrete c;
+ABC& abc = c;
+
+auto b = std::cref(abc)();
-- 
2.11.4.GIT