ruby 1.6.8-preview1 で -w を付けると警告がやかましいという
報告を受けました。新たなクラスに initialize メソッドを定義した
だけで文句を言われます。1.7 では何も言われません。

knu@archon[2]% ruby -v -w -e 'class Foo; def initialize; end; end'
ruby 1.6.8 (2002-11-06) [i386-freebsd5]
-e:1: warning: overriding global function `initialize'
knu@archon[2]% ruby -rthread -w -e ''
/usr/local/lib/ruby/1.6/thread.rb:35: warning: overriding global function `initialize'
/usr/local/lib/ruby/1.6/thread.rb:111: warning: overriding global function `initialize'
/usr/local/lib/ruby/1.6/thread.rb:148: warning: overriding global function `initialize'
/usr/local/lib/ruby/1.6/thread.rb:209: warning: overriding global function `initialize'
/usr/local/lib/ruby/1.6/thread.rb:242: warning: overriding global function `push'
/usr/local/lib/ruby/1.6/thread.rb:254: warning: overriding global function `pop'
/usr/local/lib/ruby/1.6/thread.rb:276: warning: overriding global function `num_waiting'

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Akinori MUSHA aka / (_ /  ( (__(  @ iDaemons.org / and.or.jp

"When I leave I don't know what I'm hoping to find
              When I leave I don't know what I'm leaving behind.."