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[Caml-list] A grave bug in logical shift right op?
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Date: -- (:)
From: Andrew Lenharth <andrewl@d...>
Subject: Re: [Caml-list] A grave bug in logical shift right op?
Section 6.2.1 of the manual is useful:
Integer values are integer numbers from -2^30 to 2^30-1, that is -1073741824 to 1073741823. The implementation may support a wider range of integer values: on 64-bit platforms, the current implementation supports integers ranging from -2^62 to 2^62-1.

You are experiencing overflow.  One bit of integers are used for tagging purposes (if I recall correctly).  Int32 is a boxed type.

Andrew Lenharth

On Fri, Nov 07, 2003 at 05:34:59AM +0200, Eray Ozkural wrote:
> I'm using the debian package in testing....
> 
> orion:fealn-attack$ ledit ocaml
>         Objective Caml version 3.07+2
> 
> # Printf.printf "%X" 0xffffffff;;
> 7FFFFFFF- : unit = ()
> # Printf.printf "%lx" (Int32.of_int 0xffffffff);;
> ffffffff- : unit = ()
> # -1 lsr 24;;
> - : int = 127
> # Int32.shift_right_logical (Int32.of_int (-1)) 24;;
> - : int32 = 255l
> 
> What's going on here? Something's eating the most significant bit in
> both hexadecimal output routine and the logical shift right
> operator. Somebody please help me! My cipher isn't working!!!
> 
> Confused,
> 
> -- 
> Eray Ozkural (exa) <erayo@cs.bilkent.edu.tr>
> Comp. Sci. Dept., Bilkent University, Ankara  KDE Project: http://www.kde.org
> www: http://www.cs.bilkent.edu.tr/~erayo  Malfunction: http://mp3.com/ariza
> GPG public key fingerprint: 360C 852F 88B0 A745 F31B  EA0F 7C07 AE16 874D 539C
> 
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