Re: [boost] static_assert and MWCW8.3

From: Giovanni Bajo (giovannibajo_at_[hidden])
Date: 2003-12-21 21:43:44

Beman Dawes wrote:

> Could you please put together a little program that illustrates the
> bug? I'm guessing it will help to have a complete program.

Sure.

-----------------------------------------------------------------------------
#include <iostream>

using namespace std;

template <typename DerivedT>
struct Base
{
    Base()
    { cout << "Base::Base()" << endl; }

    ~Base()
    { cout << "Base::~Base()" << endl; }

    void test(void) const
    {
        const DerivedT & derivedThis = static_cast<const DerivedT&>(*this);
    }
};

template <typename Q>
struct Derived : public Base<Derived<Q> >
{
    Derived()
    { cout << "Derived::Derived()" << endl; }

    template <typename Q>
    Derived(Q )
    { cout << "Derived::Derived(Q)" << endl; }

    ~Derived()
    { cout << "Derived::~Derived()" << endl; }
};

int main()
{
    Derived<void> d;
    d.test();
}
-----------------------------------------------------------------------------

MWCW 8.3 output:
Base::Base()
Derived::Derived()
Base::Base()
Derived::Derived(Q)
Base::~Base()
Derived::~Derived()
Base::~Base()
Derived::~Derived()
Base::~Base()

Expected output (double-checked with Comau & MSVC71):
Base::Base()
Derived::Derived()
Derived::~Derived()
Base::~Base()

Joel, you were right, you need a templated copy-ctor to trigger the bug!
Beman, I understand MW has already version 9, but I don't know if it's public
or not. Either way, it wouldn't hurth to Spirit Development if we could get a
copy. If you are in good relation with them, maybe you can praise for this.

We found also other minor bugs, but it takes time to isolate them :) There was
also a bug in the standard library (std::string(iter,iter) constructor) which I
already submitted to the website form, together with a patch to fix it.

Giovanni Bajo