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To: 9fans@cse.psu.edu
Subject: Re: [9fans] USED() macro
From: Charles Forsyth <forsyth@terzarima.net>
Date: Sat, 12 Nov 2005 11:18:21 +0000
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perhaps it could use if(&x) instead of if(x)
to cope with structures as well

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Subject: [9fans] USED() macro
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In plan9port, USED() is defined as

        #define USED(x) if(x){}else{}

Does it mean that USED() can only be applied on variables of "scalar
types"? But r is of a struct type in

        void
        drawresizewindow(Rectangle r)
        {
        	USED(r);
        	
        	bad();
        }

in $PLAN9/src/libdraw/nowsys-wsys.c.

When compiling, 9c complains on that. A bug? Or an extension of Plan 9's
C dialect?

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