Re: auto_ptr who is right?

// > MSVC8 is currently the latest (released) compiler. Could you
provide a
// > little program to show the error?
// Try this one with MSVC++ 8.0 and g++ 3.4.4 (or later).
// If both give the same results the error is fixed in your version of
MSVC++.
// If the VC++-Version calls A1::f() this is the error.
// In that case (as I've already mentioned) there is a wrong static
cast in <memory>.

#include<memory>
#include<fstream>

std::ofstream log;

struct A1
{
    A1() {
        log << "A1::A1()\n";
    }

    virtual void f() {
        log << "A1::f() should never be called.\n";
    }

    virtual ~A1() {
        log << "A1::~A1()\n";
    }
};

struct A2
{
    A2() {
        log << "A2::A2()\n";
    }

    virtual void g() {
        log << "A2::g() should be called the first time.\n";
    }

    virtual ~A2() {
        log << "A2::~A2()\n";
    }
};

struct B: public A1, public A2
{
    B() {
        log << "B::B()\n";
    }

    virtual void g() {
        log << "B::g() should be called the second time.\n";
    }

    virtual ~B() {
        log << "B::~B()\n";
    }
};

void f(bool b)
{
    std::auto_ptr<A2> pA2;

    if(b)
        pA2 = std::auto_ptr<B>(new B());
    else
        pA2 = std::auto_ptr<A2>(new A2());

    pA2->g();
}

int main()
{
    log.open("log");
    if(!log) return -1;

    f(false);
    f(true);

    log.close();
    return 0;
}