From: Tanaka Akira <akr@...17n.org>
Date: 2006-03-01T19:39:15+09:00
Subject: Re: Symbols overlap ordinary objects, especially on OS X (Was: Re: Problem with weak references on OS X 10.3)

In article <92f5f81d0602281855g27e78f4eua8bf20e0b8e47b68@mail.gmail.com>,
  "Evan Webb" <evanwebb@gmail.com> writes:

> Akira's patch is much more acceptable imho because it doesn't change
> the already pretty hardset semantics of the VALUE meaning.

To be fair, no one propose to change the VALUE meaning.

The matter is object_id which is used by Kernel#object_id
and ObjectSpace._id2ref.

> In
> addition, the other patch has a significant performance / memory
> impact that should be considered before accepting the patch. By moving
> fixnum down by a full 4 powers of 2, and triggering Bignum conversion
> much earlier than is currently seen, memory utilization patterns will
> change significantly for anyone working with decently large integers.

The performance issue exists.  However I'm not sure that it
is significant because Kernel#object_id is used not so
common.  ObjectSpace._id2ref is used rarely and it should
be.
-- 
Tanaka Akira