Path: utzoo!attcan!uunet!husc6!bbn!uwmcsd1!leah!itsgw!sun.soe.clarkson.edu!batcomputer!eacj
From: eacj@batcomputer.tn.cornell.edu (Julian Vrieslander)
Newsgroups: comp.sys.mac.programmer
Subject: Float to integer conversion problem in LSC 3.0?
Keywords: Lightspeed, LSC, conversion
Message-ID: <5813@batcomputer.tn.cornell.edu>
Date: 8 Aug 88 04:45:23 GMT
Reply-To: eacj@tcgould.tn.cornell.edu (Julian Vrieslander)
Organization: Cornell Theory Center, Cornell University, Ithaca NY
Lines: 23

I hope someone can explain this one for me.  The following code fragment
is a simplified version of a routine that was giving me unexpected
results.  The results below were obtained in LightspeedC version 3.0,
running under System 6.0:

        double d;
        long m,n;
	
        m = 126.0;          /* m becomes 126 */	
        d = 12.6 * 10.0;    /* d becomes 126 */
        n = d;              /* n becomes 125 !! */
		
I cannot understand why n gets "rounded down" to 125.  Am I missing
something subtle about C syntax or IEEE type conversions, or is this a bug
in SANE or LSC?  The variable values shown in the comments were verified
with the LSC debugger and with my own debugging dialog.  If I use the
debugger to force a value of 126.0 into d before the last line is
executed, then n gets the correct result.  What's happening here?    
-- 
Julian Vrieslander     "Don't rush me... you'll get a rotten miracle."
Neurobiology & Behavior, W250 Mudd Hall, Cornell University, Ithaca NY 14853    
UUCP: {cmcl2,decvax,rochester,uw-beaver,ihnp4}!cornell!batcomputer!eacj
INTERNET: eacj@tcgould.tn.cornell.edu     BITNET: eacj@CRNLTHRY