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From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.lang.c
Subject: Re: sizeof a struc field
Message-ID: <11227@smoke.BRL.MIL>
Date: 6 Oct 89 18:48:46 GMT
References: <7710@microsoft.UUCP> <11086@smoke.BRL.MIL> <131@dtoa3.dt.navy.mil> <11185@smoke.BRL.MIL> <7653@cdis-1.uucp>
Reply-To: gwyn@brl.arpa (Doug Gwyn)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 6

In article <7653@cdis-1.uucp> tanner@cdis-1.uucp (Dr. T. Andrews) writes:
>I should be pleased to hear WHY (((type *)0)->anything) is disallowed
>in the context of compile-time expressions.

Because (type *)0 is SYNTACTICALLY a null pointer, and there is a
prohibition against using a null pointer as the left operand of ->.