From: Simonson, Lucanus J (lucanus.j.simonson_at_[hidden])
Date: 2007-10-11 14:18:36
gpd wrote:
> I do not think we want to consciously introduce these kind of bugs in
>a boost library.
Let's not jump to conclusions before we've thought this through. You
are saying that the compiler might assume that a pointer to an object of
type A can't possibly be an alias for a pointer of type B, which
*inherits* from type A because A and B are different types? That just
doesn't make any sense. Obviously A could be an alias for an object of
type B, even if the standard says that an object of type A might not be
encapsulated within an object of type B and therefore cast from A to B
might produce undefined behavior, it doesn't mean that the compiler
would ever misconstrue that the mean there is no legitimate circumstance
in which a developer would cast an object of type A to B, or B to A,
because that is expressly the purpose of subtyping and static_cast. It
wouldn't just break non-standard compliant code; it would break all
code. Therefore, it is safe to assume that what I'm doing, which
currently works, will continue to work in the future.
Luke