Path: utzoo!attcan!uunet!husc6!bloom-beacon!gatech!uflorida!haven!ncifcrf!nlm-mcs!adm!smoke!gwyn
From: gwyn@smoke.ARPA (Doug Gwyn )
Newsgroups: comp.lang.c
Subject: Re: malloc vs calloc and invalid pointers
Message-ID: <8593@smoke.ARPA>
Date: 3 Oct 88 03:31:30 GMT
References: <13731@mimsy.UUCP> <827@goofy.megatest.UUCP>
Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 13

In article <827@goofy.megatest.UUCP> djones@megatest.UUCP (Dave Jones) writes:
>Now for the other question: Is it guaranteed that the actual memory
>allocated (static, automatic, or malloc) for a variable foo is always
>at least sizeof(foo)?

No, under some circumstances an attempt to access some bytes of the
virtual object "foo" might fail.  For example, if "foo" is a structure
with a hole at the end.

>  /* Might the following "step on" char a or char z? */

No, the objects are non-overlapping as a consequence of several
constraints within the dpANS.