Path: utzoo!utgpu!utstat!jarvis.csri.toronto.edu!mailrus!uflorida!haven!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn )
Newsgroups: comp.lang.c
Subject: Re: Contiguous Arrays
Message-ID: <9773@smoke.BRL.MIL>
Date: 2 Mar 89 22:54:01 GMT
References: <2508@ssc-vax.UUCP> <8943@alice.UUCP> <1828@valhalla.ee.rochester.edu> <8966@alice.UUCP> <7389@killer.DALLAS.TX.US>
Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 22

In article <7389@killer.DALLAS.TX.US> chasm@killer.DALLAS.TX.US (Charles Marslett) writes:
>> The easiest case is if I give you a strictly checking C implementation
>> in which evaluating &space[0]-101 causes your program to terminate
>> with an error diagnostic.
>I did not disagree that it was possible to design a compiler/computer
>combination that had this difficulty -- my point was that given the amount
>of code it was likely to break, would anyone write such a compiler.

There are compilers like that for architectures like that, as
recently explained in detail by somebody else, and reasonably-
written code works fine.  Why do you think it should be valid
to express the address of a nonexistent object?

>Before the recent rounds of Ansi drafts, there was no requirement (oops,
>someone may nail me on this, but if I err in detail, something had to be
>unspecified) that sizeof(xxx) return the size of xxx in units of "char"s.

Yes, the units of "sizeof" weren't specified.  Since all common
early implementations of C chose to use units of chars, too much
code became utterly dependent on sizeof(char)==1.  I argued for
not requiring that in the proposed standard, but was outnumbered
by those who wanted to retroactively bless that assumption.