From: Peter Dimov (pdimov_at_[hidden])
Date: 2007-11-03 14:28:28
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;
};
and the standard requires a reinterpret_cast to yield a pointer to the first
element (9.2/17).
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).