--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libstdc++-v3/testsuite/20_util/shared_ptr/comparison/cmp_c++20.cc	Mon May 25 07:50:57 2020 +0900
@@ -0,0 +1,106 @@
+// Copyright (C) 2020 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-options "-std=gnu++2a" }
+// { dg-do run { target c++2a } }
+
+#include <memory>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+  std::shared_ptr<int> p0, p00;
+  VERIFY( p0 == p00 );
+  VERIFY( !(p0 < p00) );
+  VERIFY( !(p0 > p00) );
+  VERIFY( p0 <= p00 );
+  VERIFY( p0 >= p00 );
+  VERIFY( std::is_eq(p0 <=> p00) );
+
+  std::shared_ptr<int> p1(new int(1));
+  VERIFY( p1 == p1 );
+  VERIFY( !(p1 < p1) );
+  VERIFY( !(p1 > p1) );
+  VERIFY( p1 <= p1 );
+  VERIFY( p1 >= p1 );
+  VERIFY( std::is_eq(p1 <=> p1) );
+
+  std::shared_ptr<int> p11 = p1;
+  VERIFY( p11 == p1 );
+  VERIFY( !(p11 < p1) );
+  VERIFY( !(p11 > p1) );
+  VERIFY( p11 <= p1 );
+  VERIFY( p11 >= p1 );
+  VERIFY( std::is_eq(p11 <=> p1) );
+
+  std::shared_ptr<const int> p2(new int(1));
+  VERIFY( p1 >= p1 );
+  VERIFY( p1 != p2 );
+  VERIFY( (p1 < p2) || (p1 > p2) );
+  VERIFY( (p1 <= p2) || (p1 >= p2) );
+  VERIFY( std::is_neq(p1 <=> p2) );
+
+  VERIFY( p1 != p0 );
+  VERIFY( !(p1 < p0) );
+  VERIFY( p1 > p0 );
+  VERIFY( !(p1 <= p0) );
+  VERIFY( p1 >= p0 );
+  VERIFY( std::is_gt(p1 <=> p0) );
+  VERIFY( std::is_lt(p0 <=> p1) );
+}
+
+void
+test02()
+{
+  std::shared_ptr<int> p0;
+  VERIFY( p0 == nullptr );
+  VERIFY( !(p0 < nullptr) );
+  VERIFY( !(p0 > nullptr) );
+  VERIFY( p0 <= nullptr );
+  VERIFY( p0 >= nullptr );
+  VERIFY( std::is_eq(p0 <=> nullptr) );
+
+  VERIFY( nullptr == p0 );
+  VERIFY( !(nullptr < p0) );
+  VERIFY( !(nullptr > p0) );
+  VERIFY( nullptr <= p0 );
+  VERIFY( nullptr >= p0 );
+  VERIFY( std::is_eq(nullptr <=> p0) );
+
+  std::shared_ptr<int> p1(new int(1));
+  VERIFY( p1 != nullptr );
+  VERIFY( !(p1 < nullptr) );
+  VERIFY( p1 > nullptr );
+  VERIFY( !(p1 <= nullptr) );
+  VERIFY( p1 >= nullptr );
+  VERIFY( std::is_gt(p1 <=> nullptr) );
+
+  VERIFY( nullptr != p1 );
+  VERIFY( nullptr < p1 );
+  VERIFY( !(nullptr > p1) );
+  VERIFY( nullptr <= p1 );
+  VERIFY( !(nullptr >= p1) );
+  VERIFY( std::is_lt(nullptr <=> p1) );
+}
+
+int
+main()
+{
+  test01();
+  test02();
+}