From:	"Chris A. Triebel" <cat AT sun4 DOT iol DOT unh DOT edu>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: array-bound-checking
Date:	Thu, 19 Sep 1996 08:19:08 -0400
Organization:	University of New Hampshire - Durham, NH
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To:	djgpp AT delorie DOT com
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On Thu, 19 Sep 1996, A.Appleyard wrote:

>   (2) One thing that I miss in C is optional array-bound-checking like I found
> so useful in Algol-like languages and even in primitive `autocodes' for
> mainframes long before there were desktop computers; that facility quickly and
> easily spotted many out-of-bounds store accesses that in C programs are often
> the devil's own job to track down. Is putting an array bound in these C or C++
> constructions forbidden, or is it allowed but ignored?:-
>     int zxcvbnm(int n,double x[n]) { ...... }
>     double *x[n+2];
>   If it is allowed, it would provide a way to specify size of parametric and
> pointed-to arrays for a possible array-bound-check compiler option.

I think that it goes against C and C++ grain to do things like that.  It 
takes time to do the checking and reduces flexibility in some ways.  If 
my history lessons are correct C was developed to be as fast as possible, 
and to leave as small a footprint as possible.  It has been left to the 
programmer to determine what checks are done and how to set them up.

But there is a way to do this and a whole lot more.  Use C++, create or 
have created a template class which will contain an array of any type and 
put the necessary bounds checking code in there.  Classes are just a 
fancy TYPE, like int, char, etc ... They can generally be made very 
flexible at the expense of speed/size.  If I remember correctly djgpp has 
a bunch of template classes in the library, but I never looked at or used 
them.  I tend to write my own when I need it.  You sound like you need a 
general form of class, so maybe the distributed stuff will be 
applicable.

The only requirement to the above is that you would need to use C++.

Hope I've been of help
cat

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