Path: utzoo!censor!isgtec!peter
From: peter@isgtec.UUCP (Peter Curran)
Newsgroups: comp.lang.c
Subject: Re: Zero Length Arrays Allowed in C Standard?
Message-ID: <246@isgtec.UUCP>
Date: 13 Dec 89 18:09:48 GMT
References: <2298@jato.Jpl.Nasa.Gov> <11715@smoke.BRL.MIL> <480@codonics.COM> <70188@psuecl.bitnet> <12468@ulysses.homer.nj.att.com> <233@isgtec.UUCP>
Reply-To: peter@isgtec.UUCP (Peter Curran)
Organization: ISG Technologies Inc., Mississauga, Ontario
Lines: 15

This is a re-posting, due to technical difficulties.

WIthout repeating all the discussion, much of this topic has been centred
around a single zero-length array in a structure, for which the actual
size is to be determined when an instance is malloc'd.

The Rationale document (my copy is X3J11/88-091, 13 May 1988), in section
3.5.4.2, pp. 54-55, suggests the use of array size "1".  This works
just as well as zero, except you have to subtract 1 (or sizeof(elt[0]))
from the amount malloc'd (except for the most common use, a variable-length
string, where the initial element accounts for the terminating NUL).

I realize the Rationale is not part of the standard, but I think it
would take an awfully brave implementor to disallow a construct
that the Rationale condones.