DJ Delorie wrote: >>> reinterpret_cast doesn't require that the intermediate form have the >>> same bit pattern. >> Exactly so. However, all valid pointers must be handles, so unless the >> 32-bit address space is "sparse", something will go wrong.
I didn't help things here by saying "handles"; I meant "handled". Sorry! > I would go so far as to say that it's defined (hence supported) if the > intermediate form is at least as many bits as the other types. I'm not sure if I understand. In ISO C++, it would be fine for "char *" to have more bits than all other pointers. The standard says X* -> Y* -> X* is value-preserving if Y has no stricter alignment than X. Since "char" has weak alignment requirements, Y can be "char". Is that what you mean? In ISO C++, there's of course no notion of "char *far" or "char *near"; there's just "char *". So, there's no way to directly map your intended type system onto the conversion sequence above. The spirit of the standard would seem to be that "X* near" -> "X* far" -> "X* near" be value-preserving, but to make no guarantees about "X* far" -> "X* near" -> "X* far". -- Mark Mitchell CodeSourcery [EMAIL PROTECTED] (650) 331-3385 x713
