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From: friesen@psivax.UUCP (Stanley Friesen)
Newsgroups: net.unix-wizards
Subject: Re: Re: PCC, lint bug
Message-ID: <703@psivax.UUCP>
Date: Tue, 3-Sep-85 13:08:29 EDT
Article-I.D.: psivax.703
Posted: Tue Sep  3 13:08:29 1985
Date-Received: Sun, 8-Sep-85 05:02:17 EDT
References: <1152@brl-tgr.ARPA>
Reply-To: friesen@psivax.UUCP (Stanley Friesen)
Organization: Pacesetter Systems Inc., Sylmar, CA
Lines: 29
Summary: 

In article <1152@brl-tgr.ARPA> root%bostonu.csnet@csnet-relay.arpa (BostonU SysMgr) writes:
>
>
>WRONG WRONG WRONG
>
>THE  ERROR IS ALLOWING THE DECLARATION TO PASS BOTH C AND LINT:
>
>	int x[STUFF][THING] ;	/* the name 'x' is a pointer to an int */
>	int **xp = x ;		/* not a pointer to a pointer */
>
>I do not believe *any* reading of 'x' lets it be a pointer to a pointer.

	Still wrong: x is a pointer to an array of THING int's!
This is *not* the same as a pointer to an int or a pointer to a
pointer to an int! The difference shows up in the following:

	(x + 1) == &x[1]  *not* &x[0][1]
that is adding one to a pointer increments it by *the* *size* *of*
*the* *object* pointed to - in this case sizeof(int [THING]) not
sizeof(int). The correct declarations above would be:

	int x[STUFF][THING];
	int *xp[THING] = x;
-- 

				Sarima (Stanley Friesen)

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