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From: chris@mimsy.umd.edu (Chris Torek)
Newsgroups: comp.lang.c
Subject: Re: Array bounds checking with C????
Message-ID: <26196@mimsy.umd.edu>
Date: 25 Aug 90 04:31:30 GMT
References: <7611@ucdavis.ucdavis.edu>
Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742
Lines: 15

In article <7611@ucdavis.ucdavis.edu> kuan@iris.ucdavis.edu
(Frank [Who me?] Kuan) writes:
>Why is it that most C compilers don't seem to [check array bounds]?

Mostly because it is hard.  Given `int *p', is `p[-1] = 3' valid?
That depends on the value of p....

There is a company called Saber that produces a product called
Saber-C that does this and more.  It works quite well, although last
I had heard it still objected to `&arr[sizeof arr/sizeof *arr]',
which is Officially Legal.  (Fortunately you can turn off each
individual objection.)
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 405 2750)
Domain:	chris@cs.umd.edu	Path:	uunet!mimsy!chris