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      1 //===----------------------------------------------------------------------===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is dual licensed under the MIT and the University of Illinois Open
      6 // Source Licenses. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 // TODO: Make this test pass for all standards.
     11 // XFAIL: c++98, c++03
     12 
     13 // <type_traits>
     14 
     15 // __convert_to_integral(Tp)
     16 
     17 // Test that the __convert_to_integral functions properly converts Tp to the
     18 // correct type and value for integral, enum and user defined types.
     19 
     20 #include <limits>
     21 #include <type_traits>
     22 #include <cstdint>
     23 #include <cassert>
     24 
     25 #include "user_defined_integral.hpp"
     26 
     27 template <class T>
     28 struct EnumType
     29 {
     30   enum type : T {E_zero, E_one};
     31 };
     32 
     33 
     34 template <class From, class To>
     35 void check_integral_types()
     36 {
     37   typedef std::numeric_limits<From> Limits;
     38   const From max = Limits::max();
     39   const From min = Limits::min();
     40   {
     41   auto ret = std::__convert_to_integral((From)max);
     42   assert(ret == max);
     43   ret = std::__convert_to_integral((From)min);
     44   assert(ret == min);
     45   static_assert(std::is_same<decltype(ret), To>::value, "");
     46   }
     47   {
     48   UserDefinedIntegral<From> f(max);
     49   auto ret = std::__convert_to_integral(f);
     50   assert(ret == max);
     51   f.value = min;
     52   ret = std::__convert_to_integral(f);
     53   assert(ret == min);
     54   static_assert(std::is_same<decltype(ret), To>::value, "");
     55   }
     56   {
     57   typedef typename EnumType<From>::type Enum;
     58   Enum e(static_cast<Enum>(max));
     59   auto ret = std::__convert_to_integral(e);
     60   assert(ret == max);
     61   e = static_cast<Enum>(min);
     62   ret = std::__convert_to_integral(min);
     63   assert(ret == min);
     64   static_assert(std::is_same<decltype(ret), To>::value, "");
     65   }
     66 }
     67 
     68 
     69 template <class From, class To>
     70 void check_enum_types()
     71 {
     72   auto ret = std::__convert_to_integral((From)1);
     73   assert(ret == 1);
     74   static_assert(std::is_same<decltype(ret), To>::value, "");
     75 }
     76 
     77 
     78 enum enum1 { zero = 0, one = 1 };
     79 enum enum2 : unsigned long {
     80   value = std::numeric_limits<unsigned long>::max()
     81 };
     82 
     83 int main()
     84 {
     85   check_integral_types<bool, int>();
     86   check_integral_types<char, int>();
     87   check_integral_types<signed char, int>();
     88   check_integral_types<unsigned char, int>();
     89   check_integral_types<wchar_t, decltype(((wchar_t)1) + 1)>();
     90   check_integral_types<char16_t, int>();
     91   check_integral_types<char32_t, uint32_t>();
     92   check_integral_types<short, int>();
     93   check_integral_types<unsigned short, int>();
     94   check_integral_types<int, int>();
     95   check_integral_types<unsigned, unsigned>();
     96   check_integral_types<long, long>();
     97   check_integral_types<unsigned long, unsigned long>();
     98   check_integral_types<long long, long long>();
     99   check_integral_types<unsigned long long, unsigned long long>();
    100 #ifndef _LIBCPP_HAS_NO_INT128
    101   check_integral_types<__int128_t, __int128_t>();
    102   check_integral_types<__uint128_t, __uint128_t>();
    103 #endif
    104     // TODO(ericwf): Not standard
    105   typedef std::underlying_type<enum1>::type Enum1UT;
    106   check_enum_types<enum1, decltype(((Enum1UT)1) + 1)>();
    107   typedef std::underlying_type<enum2>::type Enum2UT;
    108   check_enum_types<enum2, decltype(((Enum2UT)1) + 1)>();
    109 }
    110