libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs-2.cc

// { dg-options "-funsigned-char -fshort-enums" }
// { dg-do compile { target c++11 } }

// 2007-05-03  Benjamin Kosnik  <bkoz@redhat.com>
//
// Copyright (C) 2007-2023 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>

// Ensure that this enum has "short" as its underlying type.
enum test_enum { first_selection = ((unsigned char)-1) + 1 };

void test01()
{
  using std::make_signed;
  using std::is_same;
  using std::is_signed;
  using std::is_volatile;

  // Positive tests.
  typedef make_signed<const int>::type  	test2_type;
  static_assert(is_same<test2_type, const int>::value, "");

  typedef make_signed<const unsigned int>::type  	test21c_type;
  static_assert(is_same<test21c_type, const signed int>::value, "");

  typedef make_signed<volatile unsigned int>::type  	test21v_type;
  static_assert(is_same<test21v_type, volatile signed int>::value, "");

  typedef make_signed<const volatile unsigned int>::type  	test21cv_type;
  static_assert(is_same<test21cv_type,
		const volatile signed int>::value, "");

  typedef make_signed<const char>::type  	test22_type;
  static_assert(is_same<test22_type, const signed char>::value, "");

  typedef make_signed<volatile wchar_t>::type  	test23_type;
  static_assert(is_signed<test23_type>::value
                 && is_volatile<test23_type>::value
                 && sizeof(test23_type) == sizeof(volatile wchar_t), "");

  typedef make_signed<test_enum>::type  	test24_type;
  static_assert(is_same<test24_type, short>::value, "");

#ifndef __STRICT_ANSI__
  // GNU Extensions.
#ifdef __SIZEOF_INT128__
  typedef make_signed<unsigned __int128>::type  test25_type;
  static_assert(is_same<test25_type, __int128>::value, "");

  typedef make_signed<__int128>::type  	        test26_type;
  static_assert(is_same<test26_type, __int128>::value, "");
#endif
#endif
}