Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!crdgw1!crdos1!davidsen
From: davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr)
Newsgroups: comp.arch
Subject: Re: 64 bits
Message-ID: <2418@crdos1.crd.ge.COM>
Date: 10 Aug 90 13:03:28 GMT
References: <5539@darkstar.ucsc.edu> <13285@yunexus.YorkU.CA> <30728@super.ORG> <13667@cbmvax.commodore.com> <40644@mips.mips.COM> <1990Aug8.042631.7093@nlm.nih.gov> <1990Aug8.215735.4197@zoo.toronto.edu> <46173@ism780c.isc.com>
Reply-To: davidsen@crdos1.crd.ge.com (bill davidsen)
Organization: GE Corp R&D Center, Schenectady NY
Lines: 19

In article <46173@ism780c.isc.com> marv@ism780.UUCP (Marvin Rubenstein) writes:

| But because the difference between two pointers is a number we still need a
| numeric type with the same number of bits as a pointer.

  True, but it's not as bad as it might seem, at least in C, since it's
the number of items, not bytes, and unless the array is type char the
limit is larger.

  I would expect new systems to have an int large to hold the ordinal
of any byte in memory, but that doesn't imply that a pointer must be
the same format or even size as an int. There may be good reasons why a
pointer is larger (more bits) than an int, so storing a pointer in an
int might not work, even if the number of bytes addressable by a
pointer will fit in an int.

-- 
bill davidsen	(davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen)
 "This is your computer. This is your computer on OS/2. Any questions?"