Bug converting unsigned to double in BSD 4.[23]

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Article #9758

#9758

From: Kenneth R. Ballou
Date: Sat, 08 Nov 1986 06:55

22 lines
1131 bytes

I recently had occasion to perform this experiment:

% cat bug.c
main ()
{
  printf ("%u\n", ~ ((unsigned) 0));
  printf ("%lf\n", (double) (~ ((unsigned) 0)));
  printf ("%lf\n", 4294967295.0); /* surely double is large enough for this? */
}
% bug
4294967295
-1.000000
4294967295.000000

The results were the same on BSD 4.2 and BSD 4.3.  Of course, the question
is, did I miss something?  (I don't believe so.)

--------
Kenneth R. Ballou		...!ucbvax!cartan!brahms!ballou
Dept. of Mathematics
University of California
Berkeley, California  94720

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Path: arc1-ca.pugleaf.net!utzoo!mnetor!seismo!lll-crg!nike!ucbcad!ucbvax!cartan!brahms!ballou
From: ballou@brahms (Kenneth R. Ballou)
Newsgroups: net.lang.c
Subject: Bug converting unsigned to double in BSD 4.[23]
Message-ID: <213@cartan.Berkeley.EDU>
Date: Sat, 8-Nov-86 01:55:37 EST
Article-I.D.: cartan.213
Posted: Sat Nov  8 01:55:37 1986
Date-Received: Sun, 9-Nov-86 03:13:06 EST
Sender: daemon@cartan.Berkeley.EDU
Reply-To: ballou@brahms (Kenneth R. Ballou)
Organization: Math Dept. UC Berkeley
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