66 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8 9// <memory>10 11// template <class T>12// struct pointer_traits<T*>13// {14// static pointer pointer_to(<details>) noexcept; // constexpr in C++2015// ...16// };17 18#include <memory>19#include <cassert>20#include <type_traits>21 22#include "test_macros.h"23 24TEST_CONSTEXPR_CXX20 bool test()25{26 // pointer_traits<T*>27 {28 int i = 0;29 static_assert(std::is_same<decltype(std::pointer_traits<int*>::pointer_to(i)), int*>::value, "");30 ASSERT_NOEXCEPT(std::pointer_traits<int*>::pointer_to(i));31 assert(std::pointer_traits<int*>::pointer_to(i) == &i);32 }33 // pointer_traits<const T*>34 {35 int const i = 0;36 static_assert(std::is_same<decltype(std::pointer_traits<const int*>::pointer_to(i)), const int*>::value, "");37 ASSERT_NOEXCEPT(std::pointer_traits<const int*>::pointer_to(i));38 assert(std::pointer_traits<const int*>::pointer_to(i) == &i);39 }40 // pointer_traits<const T*> with a non-const argument41 {42 int i = 0;43 static_assert(std::is_same<decltype(std::pointer_traits<const int*>::pointer_to(i)), const int*>::value, "");44 ASSERT_NOEXCEPT(std::pointer_traits<const int*>::pointer_to(i));45 assert(std::pointer_traits<const int*>::pointer_to(i) == &i);46 }47 return true;48}49 50int main(int, char**)51{52 test();53#if TEST_STD_VER > 1754 static_assert(test());55#endif56 57 {58 // Check that pointer_traits<void*> is still well-formed, even though it has no pointer_to.59 static_assert(std::is_same<std::pointer_traits<void*>::element_type, void>::value, "");60 static_assert(std::is_same<std::pointer_traits<const void*>::element_type, const void>::value, "");61 static_assert(std::is_same<std::pointer_traits<volatile void*>::element_type, volatile void>::value, "");62 }63 64 return 0;65}66