[boost] Re: Re: dangerous_cast<>

From: David B. Held (dheld_at_[hidden])
Date: 2002-12-09 17:46:38

"Beman Dawes" <bdawes_at_[hidden]> wrote in message
news:4.3.2.7.2.20021209164950.02245168_at_mailhost.esva.net...
> [...]
> Several committee members (Gaby, Dave Abrahams, Greg, me,
> etc.) will be happy to post something on that list if the question is
> well-formed and is one that only committee members can answer.
> [...]

I suppose: "What are static_cast<> and reinterpret_cast<> *really*
supposed to do??" isn't sufficiently well-formed? ;)

How about this:

1) Under what circumstances does the following produce defined
behavior:

static_cast<T*>(static_cast<void*>(p));

A) Any time p's value points to an actual T, or is null, or T = void
B) Only when p is of type char* and points to an actual T, or is null,
        or T = void
C) Never
D) Other

2) Under what circumstances is the following equivalent to the
above:

reinterpret_cast<T*>(p);

A) Always
B) Implementation-defined
C) Never
D) Other

Is that a reasonable statement of the problem?

Dave