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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17
// UNSUPPORTED: libcpp-no-concepts
// template<class T>
// concept default_initializable = constructible_from<T> &&
// requires { T{}; } &&
// is-default-initializable<T>;
#include <concepts>
#include <cassert>
#include "test_macros.h"
template<class T>
concept brace_initializable = requires { T{}; };
void test() {
// LWG3149
// Changed the concept from constructible_from<T>
// to constructible_from<T> &&
// requires { T{}; } && is-default-initializable <T>
struct S0 { explicit S0() = default; };
S0 x0;
S0 y0{};
static_assert(std::constructible_from<S0>);
static_assert(brace_initializable<S0>);
LIBCPP_STATIC_ASSERT(std::__default_initializable<S0>);
static_assert(std::default_initializable<S0>);
struct S1 { S0 x; }; // Note: aggregate
S1 x1;
S1 y1{}; // expected-error {{chosen constructor is explicit in copy-initialization}}
static_assert(std::constructible_from<S1>);
static_assert(!brace_initializable<S1>);
LIBCPP_STATIC_ASSERT(std::__default_initializable<S1>);
static_assert(!std::default_initializable<S1>);
const int x2; // expected-error {{default initialization of an object of const type 'const int'}}
const int y2{};
static_assert(std::constructible_from<const int>);
static_assert(brace_initializable<const int>);
LIBCPP_STATIC_ASSERT(!std::__default_initializable<const int>);
static_assert(!std::default_initializable<const int>);
const int x3[1]; // expected-error {{default initialization of an object of const type 'const int [1]'}}
const int y3[1]{};
static_assert(std::constructible_from<const int[1]>);
static_assert(brace_initializable<const int[1]>);
LIBCPP_STATIC_ASSERT(!std::__default_initializable<const int[1]>);
static_assert(!std::default_initializable<const int[1]>);
// Zero-length array extension
const int x4[]; // expected-error {{definition of variable with array type needs an explicit size or an initializer}}
const int y4[]{};
static_assert(!std::constructible_from<const int[]>);
static_assert(brace_initializable<const int[]>);
LIBCPP_STATIC_ASSERT(!std::__default_initializable<const int[]>);
static_assert(!std::default_initializable<const int[]>);
}
int main(int, char**) {
test();
return 0;
}
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