From owner-freebsd-questions  Sat Sep  1 14:30: 7 2001
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From: Archie Cobbs <archie@dellroad.org>
Message-Id: <200109012129.f81LT0M54076@arch20m.dellroad.org>
Subject: gcc -D flag
To: freebsd-questions@freebsd.org
Date: Sat, 1 Sep 2001 14:29:00 -0700 (PDT)
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Can someone tell me what I'm missing here?

    $ cat > foo.c
    int main(int ac, char **av) { return 0; }
    #if FOO == BAR
    #error
    #endif
    $ cc -o foo -Wall -DFOO=BAR foo.c
    foo.c:3: #error 
    $ cc -o foo -Wall foo.c
    foo.c:3: #error 
    $ cc -o foo -Wall -DFOO=NOTBAR foo.c
    foo.c:3: #error 

Seems like #if FOO == BAR is being evalutated as true no matter what.

This is with FreeBSD 4.3-REL, gcc 2.95.3.

-Archie

__________________________________________________________________________
Archie Cobbs     *     Packet Design     *     http://www.packetdesign.com

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