From: Logan Capaldo <logancapaldo@...>
Date: 2006-04-07T03:20:14+09:00
Subject: Re: Crashing Fixnum#** with 64 bit Ruby


On Apr 6, 2006, at 2:01 PM, Daniel Berger wrote:

> Hi all,
>
> I thought this was interesting.  Should Ruby handle this better?   
> Or is this a case of, "Don't do that."?
>
> # 32 bit Ruby, Solaris 10
>
> irb(main):001:0> (2**32).class
> => Bignum
> irb(main):002:0> (2**32) ** (2**33)
> (irb):2: warning: in a**b, b may be too big
> => Infinity
>
> ## DANGER! DANGER! WILL BRING SYSTEM TO A CRAWL!
>
> # 64 bit Ruby, Solaris 10
>
> irb(main):002:0> (2**32).class
> => Fixnum
> irb(main):003:0> (2**32) ** (2**33)
> (irb):3:in `**': failed to allocate memory (NoMemoryError)
>         from (irb):3:in `irb_binding'
>         from /opt/test/lib/ruby/1.8/irb/workspace.rb:52:in  
> `irb_binding'
>         from :0
>
> The behavior is identical with or without Rational, btw.
>
> Regards,
>
> Dan
>

Incidently I get this:
% irb
irb(main):001:0> (2**32) ** (2**32)
/usr/local/ruby/lib/ruby/1.8/rational.rb:543: warning: in a**b, b may  
be too big
=> Infinity