こんばんは、sheepman です。
以下のようなコードで落ちるのは、こういうもんなんでしょうか。

$ cat t.rb
iseq = YARVCore::InstructionSequence.compile('1')
a = iseq.to_a
a[-1] = a
YARVCore::InstructionSequence.load(a)

$ ruby-2.0 -v t.rb ruby 2.0.0 (Base: Ruby 1.9.0 2006-04-08) [i686-linux]
YARVCore 0.4.1 Rev: 525 (2006-07-18) [opts: [direct threaded code] [inline method cache] ]
warning: useless use of a literal in void context
-- stack frame ------------
0000 (0x402b0008): 00000004
0001 (0x402b000c): 00000005
0002 (0x402b0010): 402961bc
0003 (0x402b0014): 40296158
0004 (0x402b0018): 00000004
0005 (0x402b001c): 00000001
0006 (0x402b0020): 40298b88
0007 (0x402b0024): 40296158
0008 (0x402b0028): 00000004
0009 (0x402b002c): 00000001 <- lfp <- dfp
-- control frame ----------
c:0004 p:---- s:0010 b:0010 l:000009 d:000009 CFUNC  :load
c:0003 p:0059 s:0006 b:0006 l:000005 d:000005 TOP    t.rb:4
c:0002 p:---- s:0002 b:0002 l:000001 d:000001 FINISH
c:0001 p:---- s:0000 b:-001 l:000000 d:000000 ------
---------------------------
DBG> : "t.rb:4:in `<main>'"
[BUG] unexpected object
ruby 2.0.0 (2006-04-08) [i686-linux]

zsh: abort      ruby-2.0 -v t.rb

-- 
sheepman / TAMURA Takashi
sheepman sheepman.sakura.ne.jp 

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