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From: richard@aiai.ed.ac.uk (Richard Tobin)
Newsgroups: comp.lang.c
Subject: Re: Array bounds checking with C????
Message-ID: <3337@skye.ed.ac.uk>
Date: 31 Aug 90 12:11:30 GMT
References: <7611@ucdavis.ucdavis.edu> <26196@mimsy.umd.edu> <988@christopher-robin.cs.bham.ac.uk>
Reply-To: richard@aiai.UUCP (Richard Tobin)
Organization: AIAI, University of Edinburgh, Scotland
Lines: 18

In article <988@christopher-robin.cs.bham.ac.uk> cjr@christopher-robin.UUCP (Chris Ridd <RiddCJ>) writes:
>>I had heard it still objected to `&arr[sizeof arr/sizeof *arr]',
>>which is Officially Legal.

>  Why is this?  I never could figure out why accessing the first
>element *past* the end of an array should be legal.

Because it's not *accessing* it.  Note the ampersand.

It's very useful for loops:

    for(p = buf;  p < &buf[sizeof(buf)];  p++)

-- Richard
-- 
Richard Tobin,                       JANET: R.Tobin@uk.ac.ed             
AI Applications Institute,           ARPA:  R.Tobin%uk.ac.ed@nsfnet-relay.ac.uk
Edinburgh University.                UUCP:  ...!ukc!ed.ac.uk!R.Tobin