on Sat Nov 03 2007, "Peter Dimov" <pdimov-AT-pdimov.com> wrote:
David Abrahams:
(A reinterpret_cast<char*>( p ) is indirectly required to work when p is a pointer to a class type,
Where does the standard say that, and what do you mean by "work?"
Consider this code:
class X;
char * f( X * p ) { return reinterpret_cast<char*>( p ); }
This must give you a char* pointing to the first byte of *p because X's definition may be
struct X { char v; };
Any POD struct will do.
and the standard requires a reinterpret_cast to yield a pointer to the first element (9.2/17).
Nice.
Because of ODR, the complete type case must be compiled in the same way, even when X happens to not have a first member of type char (link-time code generation aside).
Right. OK, then, look for a core issue from me. It's ridiculous that reinterpret_cast should be defined to be so close to what everyone thinks it is, and yet, not quite. -- Dave Abrahams Boost Consulting http://www.boost-consulting.com