Tested for is_constructible and tuple on Linux-x64, finishing testing
the full suite on Linux-PPC64.
2016-08-29 Ville Voutilainen <ville.voutilai...@gmail.com>
PR libstdc++/77395
* include/std/type_traits (is_constructible): Forward-declare...
(__is_base_to_derived_ref): ...and use here.
* testsuite/20_util/is_constructible/77395.cc: New.
* testsuite/20_util/tuple/77395.cc: Likewise.
diff --git a/libstdc++-v3/include/std/type_traits
b/libstdc++-v3/include/std/type_traits
index baa4d1f..5085196 100644
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -1007,6 +1007,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
is_function<_From>>>::value>
struct __is_base_to_derived_ref;
+ template<typename _Tp, typename... _Args>
+ struct is_constructible;
+
// Detect whether we have a downcast situation during
// reference binding.
template<typename _From, typename _To>
@@ -1017,7 +1020,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
typedef typename remove_cv<typename remove_reference<_To
>::type>::type __dst_t;
typedef __and_<__not_<is_same<__src_t, __dst_t>>,
- is_base_of<__src_t, __dst_t>> type;
+ is_base_of<__src_t, __dst_t>,
+ __not_<is_constructible<__dst_t, _From>>> type;
static constexpr bool value = type::value;
};
diff --git a/libstdc++-v3/testsuite/20_util/is_constructible/77395.cc
b/libstdc++-v3/testsuite/20_util/is_constructible/77395.cc
new file mode 100644
index 0000000..b1fe8a0
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/is_constructible/77395.cc
@@ -0,0 +1,54 @@
+// { dg-do compile { target c++11 } }
+
+// Copyright (C) 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/>.
+
+#include <type_traits>
+#include <utility>
+
+struct derived;
+struct base
+{
+ operator derived & () &;
+ operator derived const & () const &;
+ operator derived && () &&;
+};
+
+struct derived : base {};
+
+base::operator derived & () &
+{
+ return *static_cast<derived *>(this);
+}
+
+base::operator derived const & () const &
+{
+ return *static_cast<derived const *>(this);
+}
+
+base::operator derived && () &&
+{
+ return std::move(*static_cast<derived *>(this));
+}
+
+int main()
+{
+ base b;
+ derived&& d(static_cast<derived&&>(std::move(b)));
+ derived&& d2(std::move(b));
+ static_assert(std::is_constructible<derived&&, base&&>::value, "");
+}
diff --git a/libstdc++-v3/testsuite/20_util/tuple/77395.cc
b/libstdc++-v3/testsuite/20_util/tuple/77395.cc
new file mode 100644
index 0000000..26501bf
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/tuple/77395.cc
@@ -0,0 +1,46 @@
+// { dg-do compile { target c++11 } }
+
+// Copyright (C) 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/>.
+
+#include <tuple>
+#include <utility>
+
+struct derived;
+struct base
+{
+ operator derived & () &;
+ operator derived const & () const &;
+ operator derived && () &&;
+};
+
+struct derived : base {};
+
+base::operator derived & () & { return *static_cast<derived *>(this); }
+base::operator derived const & () const & { return *static_cast<derived const
*>(this); }
+base::operator derived && () && { return std::move(*static_cast<derived
*>(this)); }
+
+std::tuple<derived &&> test(base && b)
+{
+ return std::tuple<derived &&>(std::move(b));
+}
+
+int main(int,char**)
+{
+ auto d = std::get<0>(test(derived{}));
+ return 0;
+}
