test/std/utilities/memory/storage.iterator/raw_storag_iterator.base.pass.cpp

//===----------------------------------------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

// raw_storage_iterator

#include <memory>
#include <type_traits>
#include <cassert>

int A_constructed = 0;

struct A
{
    int data_;
public:
    explicit A(int i) : data_(i) {++A_constructed;}

    A(const A& a) : data_(a.data_)  {++A_constructed;}
    ~A() {--A_constructed; data_ = 0;}

    bool operator==(int i) const {return data_ == i;}
};

int main()
{
#if __cplusplus >= 201402L
    typedef std::aligned_storage<3*sizeof(A), std::alignment_of<A>::value>::type
            Storage;
    Storage buffer;
    std::raw_storage_iterator<A*, A> it((A*)&buffer);
    assert(A_constructed == 0);
    assert(it.base() == (A*)&buffer);
    for (int i = 0; i < 3; ++i)
    {
        *it++ = A(i+1);
        A* ap = (A*)&buffer + i;
        assert(*ap == i+1);
        assert(A_constructed == i+1);
        assert(it.base() == ap + 1);  // next place to write
    }
#endif
}