こんにちは、sheepman です
次のようにすると core を吐きます。

$ ./miniruby -ve '
class Hoge
  proc{}
end
'
ruby 1.9.0 (2005-08-19) [i686-linux]
YARVCore 0.3.1 (rev: 256) [opts: ]
-e:5: [BUG] Segmentation fault
ruby 1.9.0 (2005-08-19) [i686-linux]

zsh: abort (core dumped)  ./miniruby -ve ' class Hoge   proc{} end '

以下はバックトレースです。

(gdb) bt
#0  0x4009ac11 in kill () at finddomain.c:145
#1  0x4009a895 in raise (sig=6) at ../linuxthreads/sysdeps/unix/sysv/linux/raise.c:32
#2  0x4009c008 in abort () at ../sysdeps/generic/abort.c:88
#3  0x080ccfc6 in rb_bug (fmt=0x80f040d "Segmentation fault") at ../yarv/error.c:214
#4  0x080a8f1c in sigpipe (sig=11) at ../yarv/signal.c:527
#5  <signal handler called>
#6  0x0805d14e in proc_alloc (klass=1075630580, proc=1075694720) at ../yarv/eval.c:5800
#7  0x0805d363 in rb_block_proc () at ../yarv/eval.c:5884
#8  0x080be5b7 in call_cfunc (func=0x805d350 <rb_block_proc>, recv=1075620720, len=1075480936,
    argc=0, argv=0x6) at call_cfunc.h:19
#9  0x080bca06 in th_eval (th=0x810f978, initial=0) at vm.inc:1881
#10 0x080be29e in th_eval_body (th=0x810f978) at ../yarv/vm.c:1029
#11 0x080bf385 in yarvcore_eval_iseq (iseq=1075621180) at ../yarv/yarvcore.c:233
#12 0x080bf3d1 in yarvcore_eval_parsed (node=0, file=0) at ../yarv/yarvcore.c:248
#13 0x08056d44 in ruby_exec_internal () at ../yarv/eval.c:1562
#14 0x08056d60 in ruby_exec () at ../yarv/eval.c:1574
#15 0x08056d9b in ruby_run () at ../yarv/eval.c:1591
#16 0x080551c1 in main () at ../yarv/main.c:38
#17 0x40087c1f in __libc_start_main (main=0x80551a0 <main>, argc=3, ubp_av=0x3,
    init=0x80d7424 <__libc_csu_init>, fini=0x80d746c <__libc_csu_fini>,
    rtld_fini=0x400144a0 <_rtld_local>, stack_end=0x401a8968)
    at ../sysdeps/generic/libc-start.c:225

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

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