こんにちは、sheepman です。
break と例外処理を一緒に使うと、Stack consistency error が起こります。

$ cat t.rb
proc do
  begin
    raise StandardError
    break
  rescue StandardError
  end
end.call

$ ./miniruby -v t.rb
ruby 1.9.0 (2005-11-18) [i686-linux]
YARVCore 0.3.3 (rev: 366) [opts: ]
t.rb:4: DBG> : "t.rb:1:in `call'"
DBG> : "t.rb:1:in `<main>'"
-- stack frame ------------
0x402b1008 (0000): 00000001
0x402b100c (0001): 00000004
0x402b1010 (0002): 40297a14
0x402b1014 (0003): 40297a00
0x402b1018 (0004): 00000001
0x402b101c (0005): 00000001
-- control frame ----------
c:0006 p:0020 s:0006 b:0007 l:-657 d:0006 PROC   i:block in <main> s:         -
c:0005 p:-001 s:0006 b:0006 l:0005 d:0005 FINISH i:-        s:         -
c:0004 p:-001 s:0005 b:0005 l:0004 d:0004 CFUNC  i:call     s:         -
c:0003 p:0013 s:0003 b:0003 l:-657 d:-657 TOP    i:<main>   s:
c:0002 p:-001 s:0001 b:0001 l:0000 d:0000 FINISH i:-        s:         -
c:0001 p:-001 s:0000 b:-001 l:0000 d:0000 ------ i:-        s:         -
---------------------------
[BUG] Stack consistency error (sp: 0x402b1020, bp: 0x402b1024)
ruby 1.9.0 (2005-11-18) [i686-linux]

zsh: abort      ./miniruby -v t.rb


-- 
sheepman / TAMURA Takashi
sheepman sheepman.sakura.ne.jp http://sheepman.parfait.ne.jp/

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