From: "Ya'qub" <rick AT nct-active DOT com>
Newsgroups: comp.os.msdos.djgpp
References: <37367f71 DOT 6271443 AT news DOT wanadoo DOT fr> <3736A098 DOT 55E268BE AT softhome DOT net> <373c0195 DOT 3902906 AT news DOT wanadoo DOT fr>
Subject: Re: ? array[n] or array[n+1] ?
Date: Tue, 11 May 1999 10:19:16 +0100
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

Greetings,
    With all due respect, this explanation does not seem very convincing.
Surely, the compiler *should* complain when you do such a thing as
overrunning an array. I hoped that the compiler would help such a poor
programmer as myself in catching such bugs which I suppose could cause quite
a lot of headache to locate. Can anybody else confirm that gcc makes such
assumptions that we know what we are doing and let us carry on regardless.
Also, out of curiosity, if you do overrun an array and the program has
compiled without any warning or error, is there anything that can be said
about its execution? i.e. do we know what is going to happen when the
program tries to access an element from the array beyond its length. Thanks
Regards,
Ya'qub

Gallicus <Gallicus AT caramail DOT com> wrote in message
news:373c0195 DOT 3902906 AT news DOT wanadoo DOT fr...
> On Mon, 10 May 1999 19:02:16 +1000, Chris Mears <chris_mears AT softhome DOT net>
> wrote:
>
> >Because you're overrunning the array.  "int bit[63][6]" means that the
> >first index must be between 0 and 62 inclusive, and the second is
> >between 0 and 5, inclusive.  I don't know why Visual C complains, but
> >the reason djgpp doesn't is because it trusts you.  It assumes you know
> >what you're doing, and lets you do it uninhibited.
> >
>
> Many thanks, Chris,  for the answer.
> I ought not to have forgotten that because it is very basic, but I was
> confused by the different reaction of DJGPP and MSVC.
>
> Gallicus.