From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: qsort() bug?  Or invalid usage???
Date: Fri, 21 Jan 2000 11:19:32 +0200
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To: djgpp AT delorie DOT com
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Eric Rudd wrote:
> 
> Yes, and equal objects must return 0.  The last time I checked, DJGPP's qsort
> implementation sometimes attempts to dereference beyond the ends of the array
> if the comparison function returns inconsistent results.

When was that ``last time''?  The implementation of `gsort' in the DJGPP
library was changed between v2.01 and v2.02.

> I don't think that a
> good implementation should do this, but I can find nothing in the ANSI standard
> that would prohibit such behavior.

AFAIK, ANSI C explicitly allows to access an array one element before the
first one, provided that you don't write there.