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