libcxx/test/std/utilities/variant/variant.variant/variant.dtor/dtor.pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // UNSUPPORTED: c++03, c++11, c++14
  10
  11 // <variant>
  12
  13 // template <class ...Types> class variant;
  14
  15 // ~variant();
  16
  17 #include <cassert>
  18 #include <type_traits>
  19 #include <variant>
  20
  21 #include "test_macros.h"
  22
  23 struct NonTDtor {
  24   static int count;
  25   NonTDtor() = default;
  26   ~NonTDtor() { ++count; }
  27 };
  28 int NonTDtor::count = 0;
  29 static_assert(!std::is_trivially_destructible<NonTDtor>::value, "");
  30
  31 struct NonTDtor1 {
  32   static int count;
  33   NonTDtor1() = default;
  34   ~NonTDtor1() { ++count; }
  35 };
  36 int NonTDtor1::count = 0;
  37 static_assert(!std::is_trivially_destructible<NonTDtor1>::value, "");
  38
  39 struct TDtor {
  40   TDtor(const TDtor &) {} // non-trivial copy
  41   ~TDtor() = default;
  42 };
  43 static_assert(!std::is_trivially_copy_constructible<TDtor>::value, "");
  44 static_assert(std::is_trivially_destructible<TDtor>::value, "");
  45
  46 int main(int, char**) {
  47   {
  48     using V = std::variant<int, long, TDtor>;
  49     static_assert(std::is_trivially_destructible<V>::value, "");
  50   }
  51   {
  52     using V = std::variant<NonTDtor, int, NonTDtor1>;
  53     static_assert(!std::is_trivially_destructible<V>::value, "");
  54     {
  55       V v(std::in_place_index<0>);
  56       assert(NonTDtor::count == 0);
  57       assert(NonTDtor1::count == 0);
  58     }
  59     assert(NonTDtor::count == 1);
  60     assert(NonTDtor1::count == 0);
  61     NonTDtor::count = 0;
  62     { V v(std::in_place_index<1>); }
  63     assert(NonTDtor::count == 0);
  64     assert(NonTDtor1::count == 0);
  65     {
  66       V v(std::in_place_index<2>);
  67       assert(NonTDtor::count == 0);
  68       assert(NonTDtor1::count == 0);
  69     }
  70     assert(NonTDtor::count == 0);
  71     assert(NonTDtor1::count == 1);
  72   }
  73
  74   return 0;
  75 }