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// { dg-do compile { target c++17 } }
// Copyright (C) 2018-2022 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 <optional>
constexpr bool f()
{
std::optional<int> o1{42};
std::optional<int> o2;
o2 = o1;
return (o1 == o2);
}
constexpr bool f2()
{
std::optional<int> o1{42};
std::optional<int> o2;
std::optional<int> o3;
o2 = o1;
o3 = std::move(o2);
return (o1 == o3);
}
void g()
{
constexpr bool b = f();
static_assert(b);
constexpr bool b2 = f2();
static_assert(b2);
}
struct NonTrivialButConstexpr
{
int dummy;
NonTrivialButConstexpr() = default;
constexpr NonTrivialButConstexpr(int val) : dummy(val) {}
NonTrivialButConstexpr(const NonTrivialButConstexpr&) = default;
NonTrivialButConstexpr(NonTrivialButConstexpr&&) = default;
constexpr NonTrivialButConstexpr&
operator=(const NonTrivialButConstexpr& other)
{
dummy = other.dummy;
return *this;
}
constexpr NonTrivialButConstexpr&
operator=(NonTrivialButConstexpr&& other)
{
dummy = other.dummy;
return *this;
}
};
constexpr bool f3()
{
std::optional<NonTrivialButConstexpr> d1, d2;
d1 = d2;
std::optional<NonTrivialButConstexpr> o1{42};
std::optional<NonTrivialButConstexpr> o2{22};
o2 = o1;
return ((*o1).dummy == (*o2).dummy && o1->dummy == o2->dummy);
}
constexpr bool f4()
{
std::optional<NonTrivialButConstexpr> d1, d2;
d1 = std::move(d2);
std::optional<NonTrivialButConstexpr> o1{42};
std::optional<NonTrivialButConstexpr> o2{22};
std::optional<NonTrivialButConstexpr> o3{33};
o2 = o1;
o3 = std::move(o2);
return ((*o1).dummy == (*o3).dummy && o1->dummy == o3->dummy);
}
void g2()
{
constexpr bool b = f3();
static_assert(b);
constexpr bool b2 = f4();
static_assert(b2);
}
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