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From: gwyn@smoke.brl.mil (Doug Gwyn)
Newsgroups: comp.std.c
Subject: Re: #if query
Message-ID: <15739@smoke.brl.mil>
Date: 6 Apr 91 04:50:47 GMT
References: <1991Apr5.161945.889@vixvax.mgi.com>
Organization: U.S. Army Ballistic Research Laboratory, APG, MD.
Lines: 7

In article <1991Apr5.161945.889@vixvax.mgi.com> cepek@vixvax.mgi.com writes:
>Does ANSI really state that
>       #if ABC == DEF
>evaluates to FALSE if symbol DEF is not defined!?

No -- undefined identifiers are replaced by 0 in #if expressions.
That was existing behavior in e.g. the Reiser CPP.