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From: steve@taumet.com (Stephen Clamage)
Newsgroups: comp.lang.c
Subject: Re: finding offset of a member ...
Message-ID: <738@taumet.com>
Date: 21 May 91 14:55:22 GMT
References: <1285@unisql.UUCP>
Organization: Taumetric Corporation, San Diego
Lines: 18

pckim@unisql.UUCP (Pyung-Chul Kim) writes:

|But, I found that our compiler (in SunOS 4.1) evaluate the expression
|in compile time by trying to 'cc -S test.c' (the test.s contains
|numeric literal for the expression).
|Then, my question is why the compiler does not accept the following
|expression?
|	char	a_array[offsetof(type,member)];
|Is it specific to our compiler?

ANSI requires that the 'offsetof' macro expand to an integral constant
expression of type 'size_t'.  Such an expression is certainly allowed
to specifiy the size of an array.  The standard Sun compilers are not
ANSI-conformant, and this appears to be yet another place where they
fail to conform.
-- 

Steve Clamage, TauMetric Corp, steve@taumet.com