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 // constexpr destructors are only supported starting with clang 10 11 // UNSUPPORTED: clang-5, clang-6, clang-7, clang-8, clang-9 12 // constexpr destructors are only supported starting with gcc 10 13 // UNSUPPORTED: gcc-8, gcc-9 14 15 // <memory> 16 17 // template <class ForwardIt> 18 // constexpr void destroy(ForwardIt, ForwardIt); 19 20 #include <memory> 21 #include <cassert> 22 23 #include "test_macros.h" 24 #include "test_iterators.h" 25 26 struct Counted { 27 int* counter_; 28 TEST_CONSTEXPR Counted(int* counter) : counter_(counter) { ++*counter_; } 29 TEST_CONSTEXPR Counted(Counted const& other) : counter_(other.counter_) { ++*counter_; } 30 TEST_CONSTEXPR_CXX20 ~Counted() { --*counter_; } 31 friend void operator&(Counted) = delete; 32 }; 33 34 TEST_CONSTEXPR_CXX20 bool test() 35 { 36 using Alloc = std::allocator<Counted>; 37 int counter = 0; 38 int const N = 5; 39 Alloc alloc; 40 Counted* pool = std::allocator_traits<Alloc>::allocate(alloc, N); 41 42 for (Counted* p = pool; p != pool + N; ++p) 43 std::allocator_traits<Alloc>::construct(alloc, p, &counter); 44 assert(counter == 5); 45 46 std::destroy(pool, pool + 1); 47 assert(counter == 4); 48 49 std::destroy(forward_iterator<Counted*>(pool + 1), forward_iterator<Counted*>(pool + 5)); 50 assert(counter == 0); 51 52 std::allocator_traits<Alloc>::deallocate(alloc, pool, N); 53 54 return true; 55 } 56 57 int main(int, char**) 58 { 59 test(); 60 #if TEST_STD_VER > 17 61 static_assert(test()); 62 #endif 63 return 0; 64 } 65