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

$ cat t.rb
Thread.new {}
Thread.pass

$ ./miniruby -v t.rb
ruby 1.9.0 (2005-11-18) [i686-linux]
YARVCore 0.3.3 (rev: 344) [opts: ]
zsh: segmentation fault (core dumped)  ./miniruby -v t.rb

以下はバックトレースです。

#0  rb_bug (fmt=0x80f1c8d "Segmentation fault") at ../yarv/error.c:161
#1  0x080a12e7 in sigsegv (sig=11) at ../yarv/signal.c:503
#2  0x4002ce8e in __pthread_clock_settime () from /lib/i686/libpthread.so.0
#3  0x400ec908 in killpg () from /lib/i686/libc.so.6
#4  0x080c8a5f in rb_bug (fmt=0x80f1c8d "Segmentation fault") at ../yarv/error.c:161
#5  0x080a12e7 in sigsegv (sig=11) at ../yarv/signal.c:503
#6  0x4002ce8e in __pthread_clock_settime () from /lib/i686/libpthread.so.0
#7  0x400ec908 in killpg () from /lib/i686/libc.so.6
#8  0x080c8a5f in rb_bug (fmt=0x80f1c8d "Segmentation fault") at ../yarv/error.c:161
#9  0x080a12e7 in sigsegv (sig=11) at ../yarv/signal.c:503
#10 0x4002ce8e in __pthread_clock_settime () from /lib/i686/libpthread.so.0
#11 0x400ec908 in killpg () from /lib/i686/libc.so.6
#12 0x080c8a5f in rb_bug (fmt=0x80f1c8d "Segmentation fault") at ../yarv/error.c:161
#13 0x080a12e7 in sigsegv (sig=11) at ../yarv/signal.c:503
#14 0x4002ce8e in __pthread_clock_settime () from /lib/i686/libpthread.so.0
#15 0x400ec908 in killpg () from /lib/i686/libc.so.6
#16 0x080c8a5f in rb_bug (fmt=0x80f1c8d "Segmentation fault") at ../yarv/error.c:161
#17 0x080a12e7 in sigsegv (sig=11) at ../yarv/signal.c:503
#18 0x4002ce8e in __pthread_clock_settime () from /lib/i686/libpthread.so.0
#19 0x400ec908 in killpg () from /lib/i686/libc.so.6
#20 0x080c8a5f in rb_bug (fmt=0x80f1c8d "Segmentation fault") at ../yarv/error.c:161
#21 0x080a12e7 in sigsegv (sig=11) at ../yarv/signal.c:503
#22 0x4002ce8e in __pthread_clock_settime () from /lib/i686/libpthread.so.0
#23 0x400ec908 in killpg () from /lib/i686/libc.so.6
#24 0x080c8a5f in rb_bug (fmt=0x80f1c8d "Segmentation fault") at ../yarv/error.c:161
#25 0x080a12e7 in sigsegv (sig=11) at ../yarv/signal.c:503
#26 0x4002ce8e in __pthread_clock_settime () from /lib/i686/libpthread.so.0
#27 0x400ec908 in killpg () from /lib/i686/libc.so.6
#28 0x080c8a5f in rb_bug (fmt=0x80f1c8d "Segmentation fault") at ../yarv/error.c:161
.....
#3627 0x400ec908 in killpg () from /lib/i686/libc.so.6
#3628 0x40029bf8 in pthread_getconcurrency () from /lib/i686/libpthread.so.0
#3629 0x40029e84 in pthread_getconcurrency () from /lib/i686/libpthread.so.0
#3630 0x400ef0b0 in exit () from /lib/i686/libc.so.6
#3631 0x0805877a in ruby_stop () at ../yarv/eval.c:296
#3632 0x080587bc in rb_eval_string (str=0x3 <Address 0x3 out of bounds>) at ../yarv/eval.c:308
#3633 0x08055e8d in main () at ../yarv/main.c:36
#3634 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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