こんばんは、sheepman です。
次のようにすると core を吐きます。

$ cat t.rb
 B = 1
 class B
   p B
 end

$ ./miniruby -v t.rb
ruby 1.9.0 (2005-11-18) [i686-linux]
YARVCore 0.3.3 (rev: 356) [opts: ]
t.rb:3: DBG> : "t.rb:2:in `<main>'"
-- stack frame ------------
0x402b1008 (0000): 00000001
0x402b100c (0001): 00000004
0x402b1010 (0002): 40298018
0x402b1014 (0003): 00000004
0x402b1018 (0004): 08140bbf <- lfp <- dfp
0x402b101c (0005): 00000003 <- bp
-- control frame ----------
c:0004 p:0006 s:0006 b:0005 l:0004 d:0004 CLASS  i:<class:B> s:         -
c:0003 p:0010 s:0003 b:0003 l:-131 d:-131 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] Segmentation fault
ruby 1.9.0 (2005-11-18) [i686-linux]

zsh: abort      ./miniruby -v t.rb

以下はバックトレースです。

(gdb) bt
#0  0x400ecc11 in kill () from /lib/i686/libc.so.6
#1  0x4002a341 in pthread_kill () from /lib/i686/libpthread.so.0
#2  0x4002a6bb in raise () from /lib/i686/libpthread.so.0
#3  0x400ec8a4 in raise () from /lib/i686/libc.so.6
#4  0x400ee008 in abort () from /lib/i686/libc.so.6
#5  0x080c8efa in rb_bug (fmt=0x80f20f1 "Segmentation fault") at ../yarv/error.c:173
#6  0x080a12f3 in sigsegv (sig=11) at ../yarv/signal.c:457
#7  0x4002ce8e in __pthread_clock_settime () from /lib/i686/libpthread.so.0
#8  0x400ec908 in killpg () from /lib/i686/libc.so.6
#9  0x080b55e0 in th_eval (th=0x813d140, initial=0) at insns.def:285
#10 0x080b888d in th_eval_body (th=0x813d140) at ../yarv/vm.c:1273
#11 0x080b9bb8 in yarvcore_eval_iseq (iseq=1076461892) at yarv.h:49
#12 0x08058798 in ruby_exec_internal () at ../yarv/eval.c:271
#13 0x080587cc in ruby_exec () at ../yarv/eval.c:283
#14 0x08058807 in ruby_run () at ../yarv/eval.c:300
#15 0x08055f05 in main () at ../yarv/main.c:36
#16 0x400d9c1f in __libc_start_main () from /lib/i686/libc.so.6

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

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