PR libstdc++/42819, DR 1315

2010-02-12  Jonathan Wakely  <jwakely.gcc@gmail.com>
	    Paolo Carlini  <paolo.carlini@oracle.com>

	PR libstdc++/42819, DR 1315
	* include/std/future (async): Use std::result_of for the template
	argument of the std::future return type; adjust everywhere.
	* testsuite/30_threads/async/42819.cc: New.
	* testsuite/30_threads/packaged_task/cons/assign_neg.cc: Adjust
	dg-error line number.
	* testsuite/30_threads/packaged_task/cons/copy_neg.cc: Likewise.
	* testsuite/30_threads/future/cons/assign_neg.cc: Likewise.
	* testsuite/30_threads/future/cons/copy_neg.cc: Likewise.
	* testsuite/30_threads/promise/cons/assign_neg.cc: Likewise.
	* testsuite/30_threads/promise/cons/assign_neg.cc: Likewise.

Co-Authored-By: Paolo Carlini <paolo.carlini@oracle.com>

From-SVN: r156742

9 files changed, 96 insertions, 16 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index b24ae7a..8dace9d 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,18 @@
+2010-02-12  Jonathan Wakely  <jwakely.gcc@gmail.com>
+	    Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR libstdc++/42819, DR 1315
+	* include/std/future (async): Use std::result_of for the template
+	argument of the std::future return type; adjust everywhere.
+	* testsuite/30_threads/async/42819.cc: New.
+	* testsuite/30_threads/packaged_task/cons/assign_neg.cc: Adjust
+	dg-error line number.
+	* testsuite/30_threads/packaged_task/cons/copy_neg.cc: Likewise.
+	* testsuite/30_threads/future/cons/assign_neg.cc: Likewise.
+	* testsuite/30_threads/future/cons/copy_neg.cc: Likewise.
+	* testsuite/30_threads/promise/cons/assign_neg.cc: Likewise.
+	* testsuite/30_threads/promise/cons/assign_neg.cc: Likewise.
+
 2010-02-11  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	* config/abi/pre/gnu.ver: Revert last changes.
diff --git a/libstdc++-v3/include/std/future b/libstdc++-v3/include/std/future
index 1ef0364..c97682d 100644
--- a/libstdc++-v3/include/std/future
+++ b/libstdc++-v3/include/std/future
@@ -119,11 +119,14 @@ namespace std
   enum class launch { any, async, sync };
 
   template<typename _Fn, typename... _Args>
-    future<typename _Fn::result_type>
+    future<typename result_of<_Fn(_Args...)>::type>
     async(launch __policy, _Fn&& __fn, _Args&&... __args);
 
   template<typename _Fn, typename... _Args>
-    future<typename _Fn::result_type>
+    typename
+    enable_if<!is_same<typename decay<_Fn>::type, launch>::value,
+              future<decltype(std::declval<_Fn>()(std::declval<_Args>()...))>
+             >::type
     async(_Fn&& __fn, _Args&&... __args);
 
 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1) \
@@ -558,7 +561,7 @@ namespace std
       friend class promise<_Res>;
       template<typename> friend class packaged_task;
       template<typename _Fn, typename... _Args>
-        friend future<typename _Fn::result_type>
+        friend future<typename result_of<_Fn(_Args...)>::type>
         async(launch, _Fn&&, _Args&&...);
 
       typedef __basic_future<_Res> _Base_type;
@@ -599,7 +602,7 @@ namespace std
       friend class promise<_Res&>;
       template<typename> friend class packaged_task;
       template<typename _Fn, typename... _Args>
-        friend future<typename _Fn::result_type>
+        friend future<typename result_of<_Fn(_Args...)>::type>
         async(launch, _Fn&&, _Args&&...);
 
       typedef __basic_future<_Res&> _Base_type;
@@ -640,7 +643,7 @@ namespace std
       friend class promise<void>;
       template<typename> friend class packaged_task;
       template<typename _Fn, typename... _Args>
-        friend future<typename _Fn::result_type>
+        friend future<typename result_of<_Fn(_Args...)>::type>
         async(launch, _Fn&&, _Args&&...);
 
       typedef __basic_future<void> _Base_type;
@@ -1322,10 +1325,10 @@ namespace std
     };
 
   template<typename _Fn, typename... _Args>
-    future<typename _Fn::result_type>
+    future<typename result_of<_Fn(_Args...)>::type>
     async(launch __policy, _Fn&& __fn, _Args&&... __args)
     {
-      typedef typename _Fn::result_type result_type;
+      typedef typename result_of<_Fn(_Args...)>::type result_type;
       std::shared_ptr<__future_base::_State> __state;
       if (__policy == launch::async)
 	{
@@ -1343,7 +1346,10 @@ namespace std
     }
 
   template<typename _Fn, typename... _Args>
-    future<typename _Fn::result_type>
+    inline typename
+    enable_if<!is_same<typename decay<_Fn>::type, launch>::value,
+              future<decltype(std::declval<_Fn>()(std::declval<_Args>()...))>
+             >::type
     async(_Fn&& __fn, _Args&&... __args)
     {
       return async(launch::any, std::forward<_Fn>(__fn),
diff --git a/libstdc++-v3/testsuite/30_threads/async/42819.cc b/libstdc++-v3/testsuite/30_threads/async/42819.cc
new file mode 100644
index 0000000..c41606e
--- /dev/null
+++ b/libstdc++-v3/testsuite/30_threads/async/42819.cc
@@ -0,0 +1,59 @@
+// { dg-do run { target *-*-freebsd* *-*-netbsd* *-*-linux* *-*-solaris* *-*-cygwin *-*-darwin* alpha*-*-osf* mips-sgi-irix6* } }
+// { dg-options " -std=gnu++0x -pthread" { target *-*-freebsd* *-*-netbsd* *-*-linux* alpha*-*-osf* mips-sgi-irix6* } }
+// { dg-options " -std=gnu++0x -pthreads" { target *-*-solaris* } }
+// { dg-options " -std=gnu++0x " { target *-*-cygwin *-*-darwin* } }
+// { dg-require-cstdint "" }
+// { dg-require-gthreads "" }
+// { dg-require-atomic-builtins "" }
+
+// Copyright (C) 2010 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 <future>
+#include <testsuite_hooks.h>
+
+int do_work1(int value) { return value; }
+int do_work2(int value) { return value * 2; }
+
+int work1(int value)
+{
+  auto handle = std::async([=] { return do_work2(value); });
+  int tmp = do_work1(value);
+  return tmp + handle.get();
+}
+
+int work2(int value)
+{
+  auto handle = std::async(do_work2, value);
+  int tmp = do_work1(value);
+  return tmp + handle.get();
+}
+
+// libstdc++/42819
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  VERIFY( work1(1) == 3 );
+  VERIFY( work2(2) == 6 );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/30_threads/future/cons/assign_neg.cc b/libstdc++-v3/testsuite/30_threads/future/cons/assign_neg.cc
index ecdc27c..eef4149 100644
--- a/libstdc++-v3/testsuite/30_threads/future/cons/assign_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/cons/assign_neg.cc
@@ -4,7 +4,7 @@
 // { dg-require-gthreads "" }
 // { dg-require-atomic-builtins "" }
 
-// Copyright (C) 2009 Free Software Foundation, Inc.
+// Copyright (C) 2009, 2010 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
@@ -35,4 +35,4 @@ void test01()
 }
 
 // { dg-error "used here" "" { target *-*-* } 34 }
-// { dg-error "deleted function" "" { target *-*-* } 578 }
+// { dg-error "deleted function" "" { target *-*-* } 581 }
diff --git a/libstdc++-v3/testsuite/30_threads/future/cons/copy_neg.cc b/libstdc++-v3/testsuite/30_threads/future/cons/copy_neg.cc
index c76075d..14d7046 100644
--- a/libstdc++-v3/testsuite/30_threads/future/cons/copy_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/cons/copy_neg.cc
@@ -4,7 +4,7 @@
 // { dg-require-gthreads "" }
 // { dg-require-atomic-builtins "" }
 
-// Copyright (C) 2009 Free Software Foundation, Inc.
+// Copyright (C) 2009, 2010 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
@@ -34,4 +34,4 @@ void test01()
 }
 
 // { dg-error "used here" "" { target *-*-* } 33 }
-// { dg-error "deleted function" "" { target *-*-* } 577 }
+// { dg-error "deleted function" "" { target *-*-* } 580 }
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/assign_neg.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/assign_neg.cc
index 69cfdd3..2b57a1c 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/assign_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/assign_neg.cc
@@ -33,4 +33,4 @@ void test01()
 }
 
 // { dg-error "used here" "" { target *-*-* } 32 }
-// { dg-error "deleted function" "" { target *-*-* } 1225 }
+// { dg-error "deleted function" "" { target *-*-* } 1228 }
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/copy_neg.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/copy_neg.cc
index b3fbdbc..baf7183 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/copy_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/copy_neg.cc
@@ -32,4 +32,4 @@ void test01()
 }
 
 // { dg-error "used here" "" { target *-*-* } 31 }
-// { dg-error "deleted function" "" { target *-*-* } 1224 }
+// { dg-error "deleted function" "" { target *-*-* } 1227 }
diff --git a/libstdc++-v3/testsuite/30_threads/promise/cons/assign_neg.cc b/libstdc++-v3/testsuite/30_threads/promise/cons/assign_neg.cc
index a52ceae..80b5e06 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/cons/assign_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/cons/assign_neg.cc
@@ -33,4 +33,4 @@ void test01()
 }
 
 // { dg-error "used here" "" { target *-*-* } 32 }
-// { dg-error "deleted function" "" { target *-*-* } 868 }
+// { dg-error "deleted function" "" { target *-*-* } 871 }
diff --git a/libstdc++-v3/testsuite/30_threads/promise/cons/copy_neg.cc b/libstdc++-v3/testsuite/30_threads/promise/cons/copy_neg.cc
index 22d44ce..27884b0 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/cons/copy_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/cons/copy_neg.cc
@@ -32,4 +32,4 @@ void test01()
 }
 
 // { dg-error "used here" "" { target *-*-* } 31 }
-// { dg-error "deleted function" "" { target *-*-* } 852 }
+// { dg-error "deleted function" "" { target *-*-* } 855 }