libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs-3.cc

   1 // { dg-do compile { target c++11 } }
   2
   3 // Copyright (C) 2015-2021 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10 //
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15 //
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 #include <type_traits>
  21
  22 template<typename T, typename I0, typename... I>
  23 struct smallest_rank
  24 : std::conditional< sizeof(T) == sizeof(I0),
  25                     I0,
  26                     typename smallest_rank<T, I...>::type >
  27 { };
  28
  29 template<typename T, typename I0>
  30 struct smallest_rank<T, I0>
  31 { using type = I0; };
  32
  33 template<typename T>
  34 using smallest_rank_t
  35   = typename smallest_rank<typename std::remove_cv<T>::type,
  36                            signed char, signed short, signed int,
  37                            signed long, signed long long>::type;
  38
  39 using std::make_signed;
  40 using std::is_same;
  41
  42 enum E1 : char { };
  43 using I1 = smallest_rank_t<E1>;
  44 static_assert(is_same<make_signed<E1>::type,       I1>::value, "");
  45 static_assert(is_same<make_signed<E1 const>::type, I1 const>::value, "");
  46
  47 enum E2 : short { };
  48 using I2 = smallest_rank_t<E2>;
  49 static_assert(is_same<make_signed<E2>::type,       I2>::value, "");
  50 static_assert(is_same<make_signed<E2 const>::type, I2 const>::value, "");
  51
  52 enum E3 : int { };
  53 using I3 = smallest_rank_t<E3>;
  54 static_assert(is_same<make_signed<E3>::type,       I3>::value, "");
  55 static_assert(is_same<make_signed<E3 const>::type, I3 const>::value, "");
  56
  57 enum E4 : long { };
  58 using I4 = smallest_rank_t<E4>;
  59 static_assert(is_same<make_signed<E4>::type,       I4>::value, "");
  60 static_assert(is_same<make_signed<E4 const>::type, I4 const>::value, "");
  61
  62 // PR libstdc++/60333
  63 enum E5 : long long { };
  64 using I5 = smallest_rank_t<E5>;
  65 static_assert(is_same<make_signed<E5>::type, I5>::value, "");
  66 static_assert(is_same<make_signed<E5 const>::type, I5 const>::value, "");
  67
  68 // PR libstdc++/85951
  69 using I6 = smallest_rank_t<char16_t>;
  70 static_assert(is_same<make_signed<char16_t>::type, I6>::value, "");
  71 static_assert(is_same<make_signed<char16_t const>::type, I6 const>::value, "");
  72 using I7 = smallest_rank_t<char32_t>;
  73 static_assert(is_same<make_signed<char32_t>::type, I7>::value, "");
  74 static_assert(is_same<make_signed<char32_t const>::type, I7 const>::value, "");
  75 #ifdef _GLIBCXX_USE_WCHAR_T
  76 using I8 = smallest_rank_t<wchar_t>;
  77 static_assert(is_same<make_signed<wchar_t>::type, I8>::value, "");
  78 static_assert(is_same<make_signed<wchar_t const>::type, I8 const>::value, "");
  79 #endif