test/std/utilities/optional/optional.object/optional.object.ctor/copy.fail.cpp


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//===----------------------------------------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

// UNSUPPORTED: c++98, c++03, c++11, c++14
// <optional>

// constexpr optional(const optional<T>& rhs);
//   If is_trivially_copy_constructible_v<T> is true, 
//    this constructor shall be a constexpr constructor.

#include <optional>
#include <type_traits>
#include <cassert>

#include "test_macros.h"

struct S {
	constexpr S()   : v_(0) {}
	S(int v)        : v_(v) {}
	S(const S &rhs) : v_(rhs.v_) {}  // make it not trivially copyable
	int v_;
	};
	

int main()
{
    static_assert (!std::is_trivially_copy_constructible_v<S>, "" );
    constexpr std::optional<S> o1;
    constexpr std::optional<S> o2 = o1;  // not constexpr
}