test/std/utilities/memory/allocator.traits/allocator.traits.members/deallocate.pass.cpp

//===----------------------------------------------------------------------===//
//
// 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: gcc-8, gcc-9

// <memory>

// template <class Alloc>
// struct allocator_traits
// {
//     static constexpr void deallocate(allocator_type& a, pointer p, size_type n);
//     ...
// };

#include <memory>
#include <cassert>
#include <cstddef>

#include "test_macros.h"
#include "incomplete_type_helper.h"

template <class T>
struct A
{
    typedef T value_type;

    TEST_CONSTEXPR_CXX20 A(int& called) : called_(called) {}

    TEST_CONSTEXPR_CXX20 void deallocate(value_type* p, std::size_t n)
    {
        assert(p == &storage);
        assert(n == 10);
        ++called_;
    }

    int& called_;

    value_type storage;
};

TEST_CONSTEXPR_CXX20 bool test()
{
    {
        int called = 0;
        A<int> a(called);
        std::allocator_traits<A<int> >::deallocate(a, &a.storage, 10);
        assert(called == 1);
    }
    {
        int called = 0;
        typedef A<IncompleteHolder*> Alloc;
        Alloc a(called);
        std::allocator_traits<Alloc>::deallocate(a, &a.storage, 10);
        assert(called == 1);
    }

    return true;
}

int main(int, char**)
{
    test();
#if TEST_STD_VER > 17
    static_assert(test());
#endif
    return 0;
}