Article View: comp.std.c
Article #2943Re: pointer comparisons
From: Stan Brown
Date: Thu, 31 Dec 1992 13:30
Date: Thu, 31 Dec 1992 13:30
26 lines
1298 bytes
1298 bytes
In article <1hsdg8INN5jm@urmel.informatik.rwth-aachen.de> berg@physik.tu-muenchen.de (Stephen R. van den Berg) writes:
>What about the following program: [of which I show only the salient parts]
>void*a,*b;
>
>main()
>{ int i; /* initial assignment deleted */
> a=malloc(1); b=malloc(1);
> i+=a>b;
> printf("%d\n",i);
> return i;
>}
>---------------------------------------
>
>Is this program *always* required to print or return "3"?
I believe this program is not obligated to print or return _anything_,
but may, in John Woods's happy phrase, "cause demons to fly out of your
nose."
Comparing pointers that point to different objects leads to an undefined
result. See ANSI section 3.3.8 (ISO 6.3.8, I believe).
--
Stan Brown, Oak Road Systems brown@Ncoast.ORG
Cleveland, Ohio, USA
What's a question that contains the word 'cantaloupe' for no apparent reason?
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Newsgroups: comp.std.c Path: arc1-ca.pugleaf.net!sparky!uunet!paladin.american.edu!gatech!usenet.ins.cwru.edu!ncoast!brown From: brown@NCoast.ORG (Stan Brown) Subject: Re: pointer comparisons Organization: Oak Road Systems, Cleveland Ohio USA Date: Thu, 31 Dec 1992 13:30:35 GMT Message-ID: <C04LIz.3DG@NCoast.ORG> References: <1hsdg8INN5jm@urmel.informatik.rwth-aachen.de> Lines: 26