| //===----------------------------------------------------------------------===// |
| // |
| // 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 |
| // constexpr destructors are only supported starting with clang 10 |
| // UNSUPPORTED: clang-5, clang-6, clang-7, clang-8, clang-9 |
| // constexpr destructors are only supported starting with gcc 10 |
| // UNSUPPORTED: gcc-8, gcc-9 |
| |
| // <memory> |
| |
| // template <class ForwardIt, class Size> |
| // constexpr ForwardIt destroy_n(ForwardIt, Size s); |
| |
| #include <memory> |
| #include <cassert> |
| |
| #include "test_macros.h" |
| #include "test_iterators.h" |
| |
| struct Counted { |
| int* counter_; |
| TEST_CONSTEXPR Counted(int* counter) : counter_(counter) { ++*counter_; } |
| TEST_CONSTEXPR Counted(Counted const& other) : counter_(other.counter_) { ++*counter_; } |
| TEST_CONSTEXPR_CXX20 ~Counted() { --*counter_; } |
| friend void operator&(Counted) = delete; |
| }; |
| |
| TEST_CONSTEXPR_CXX20 bool test() |
| { |
| using Alloc = std::allocator<Counted>; |
| int counter = 0; |
| int const N = 5; |
| Alloc alloc; |
| Counted* pool = std::allocator_traits<Alloc>::allocate(alloc, N); |
| |
| for (Counted* p = pool; p != pool + N; ++p) |
| std::allocator_traits<Alloc>::construct(alloc, p, &counter); |
| assert(counter == 5); |
| |
| Counted* np = std::destroy_n(pool, 1); |
| assert(np == pool + 1); |
| assert(counter == 4); |
| |
| forward_iterator<Counted*> it = std::destroy_n(forward_iterator<Counted*>(pool + 1), 4); |
| assert(it == forward_iterator<Counted*>(pool + 5)); |
| assert(counter == 0); |
| |
| std::allocator_traits<Alloc>::deallocate(alloc, pool, N); |
| |
| return true; |
| } |
| |
| int main(int, char**) |
| { |
| test(); |
| #if TEST_STD_VER > 17 |
| static_assert(test()); |
| #endif |
| return 0; |
| } |