Simplify std::__invoke_impl definitions

	* include/std/functional (_Unwrap): Rename to __inv_unwrap.
	(__invfwd): Adjust.
	(__invoke_impl): Remove unused template parameters.
	* testsuite/20_util/function_objects/invoke/59768.cc: Remove unused
	parameter.
	* testsuite/20_util/function_objects/invoke/ref_ext.cc: Copy 59768.cc
	and test __invoke extension for C++11.

From-SVN: r239120

4 files changed, 79 insertions, 20 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index d116231..b124d75 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,13 @@
+2016-08-04  Jonathan Wakely  <jwakely@redhat.com>
+
+	* include/std/functional (_Unwrap): Rename to __inv_unwrap.
+	(__invfwd): Adjust.
+	(__invoke_impl): Remove unused template parameters.
+	* testsuite/20_util/function_objects/invoke/59768.cc: Remove unused
+	parameter.
+	* testsuite/20_util/function_objects/invoke/ref_ext.cc: Copy 59768.cc
+	and test __invoke extension for C++11.
+
 2016-08-03  Jonathan Wakely  <jwakely@redhat.com>
 
 	* include/bits/shared_ptr_base.h (__cpp_lib_enable_shared_from_this):
diff --git a/libstdc++-v3/include/std/functional b/libstdc++-v3/include/std/functional
index 700505e..d635ef5 100644
--- a/libstdc++-v3/include/std/functional
+++ b/libstdc++-v3/include/std/functional
@@ -185,31 +185,23 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     { };
 
   template<typename _Tp, typename _Up = typename decay<_Tp>::type>
-    struct _Unwrap
+    struct __inv_unwrap
     {
-      using type = _Tp&&;
-
-      // Equivalent to std::forward<_Tp>
-      static constexpr _Tp&&
-      _S_fwd(_Tp& __t) noexcept { return static_cast<_Tp&&>(__t); }
+      using type = _Tp;
     };
 
   template<typename _Tp, typename _Up>
-    struct _Unwrap<_Tp, reference_wrapper<_Up>>
+    struct __inv_unwrap<_Tp, reference_wrapper<_Up>>
     {
       using type = _Up&;
-
-      // Get an lvalue-reference from a reference_wrapper.
-      static _Up&
-      _S_fwd(const _Tp& __t) noexcept { __t.get(); }
     };
 
   // Used by __invoke_impl instead of std::forward<_Tp> so that a
   // reference_wrapper is converted to an lvalue-reference.
-  template<typename _Tp>
-    inline typename _Unwrap<_Tp>::type
+  template<typename _Tp, typename _Up = typename __inv_unwrap<_Tp>::type>
+    inline _Up&&
     __invfwd(typename remove_reference<_Tp>::type& __t) noexcept
-    { return _Unwrap<_Tp>::_S_fwd(__t); }
+    { return static_cast<_Up&&>(__t); }
 
   template<typename _Res, typename _Fn, typename... _Args>
     inline _Res
@@ -235,16 +227,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       return ((*std::forward<_Tp>(__t)).*__f)(std::forward<_Args>(__args)...);
     }
 
-  template<typename _Res, typename _MemFun, typename _Tp, typename... _Args>
+  template<typename _Res, typename _MemPtr, typename _Tp>
     inline _Res
-    __invoke_impl(__invoke_memobj_ref, _MemFun&& __f, _Tp&& __t)
+    __invoke_impl(__invoke_memobj_ref, _MemPtr&& __f, _Tp&& __t)
     noexcept(noexcept(__invfwd<_Tp>(__t).*__f))
     { return __invfwd<_Tp>(__t).*__f; }
 
-  template<typename _Res, typename _MemFun, typename _Tp, typename... _Args>
+  template<typename _Res, typename _MemPtr, typename _Tp>
     inline _Res
-    __invoke_impl(__invoke_memobj_deref, _MemFun&& __f, _Tp&& __t,
-		  _Args&&... __args)
+    __invoke_impl(__invoke_memobj_deref, _MemPtr&& __f, _Tp&& __t)
     noexcept(noexcept((*std::forward<_Tp>(__t)).*__f))
     { return (*std::forward<_Tp>(__t)).*__f; }
 
diff --git a/libstdc++-v3/testsuite/20_util/function_objects/invoke/59768.cc b/libstdc++-v3/testsuite/20_util/function_objects/invoke/59768.cc
index 2a519ea..6aaae22 100644
--- a/libstdc++-v3/testsuite/20_util/function_objects/invoke/59768.cc
+++ b/libstdc++-v3/testsuite/20_util/function_objects/invoke/59768.cc
@@ -21,7 +21,7 @@
 #include <functional>
 
 struct A {
-  void foo(int n) { }
+  void foo(int) { }
 };
 
 void
diff --git a/libstdc++-v3/testsuite/20_util/function_objects/invoke/ref_ext.cc b/libstdc++-v3/testsuite/20_util/function_objects/invoke/ref_ext.cc
new file mode 100644
index 0000000..d7e5766
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/function_objects/invoke/ref_ext.cc
@@ -0,0 +1,58 @@
+// Copyright (C) 2015-2016 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/>.
+
+// { dg-do compile { target c++11 } }
+
+#include <functional>
+
+struct A {
+  void foo(int) { }
+};
+
+void
+test01()
+{
+  // PR libstdc++/59768
+  A a;
+  auto ref = std::ref(a);
+  std::__invoke(&A::foo, ref, 100);		// lvalue
+  std::__invoke(&A::foo, std::move(ref), 100);	// rvalue
+  const auto refc = std::ref(a);
+  std::__invoke(&A::foo, refc, 100);		// const lvalue
+  std::__invoke(&A::foo, std::move(refc), 100);	// const rvalue
+}
+
+struct B {
+  int bar = 0;
+};
+
+void
+test02()
+{
+  B b;
+  // Invocation through a reference_wrapper means the object is an lvalue.
+
+  int* ptr [[gnu::unused]];
+  auto ref = std::ref(b);
+  ptr = &std::__invoke(&B::bar, ref);
+  ptr = &std::__invoke(&B::bar, std::move(ref));
+
+  const int* cptr [[gnu::unused]];
+  auto cref = std::cref(b);
+  cptr = &std::__invoke(&B::bar, cref);
+  cptr = &std::__invoke(&B::bar, std::move(cref));
+}