[ruby-dev:24735] String#gsub causes core dump again^2

次のようにすると core を吐きます。

% ./ruby -de '
def make_unlockable_string
  callcc {|$kk|
    dest = nil
    begin
      str = "b" * 37
      n = 0
      dest = str.gsub(/\z/) {
        callcc {|k| $k = k }
       "b" * 28
      }
      n += 1
      $k.call if n == 1
    rescue RuntimeError
      p $!
    end
    $kk.call([dest, lambda { callcc {|$kk| $k.call } }])
  }
end
dest, unlock = make_unlockable_string
r, w = IO.pipe
Thread.new { r.read(dest.length, dest) }
unlock.call
dest.replace ""
loop { w << "a" * 45 }
'
Exception `RuntimeError' at -e:8 - temporal unlocking already unlocked string
#<RuntimeError: temporal unlocking already unlocked string>
Exception `RuntimeError' at -e:22 - temporal unlocking already unlocked string
-e:22:in `read': temporal unlocking already unlocked string (RuntimeError)
        from -e:22
        from -e:22:in `initialize'
        from -e:22:in `new'
        from -e:22
-e:22: [BUG] Segmentation fault
ruby 1.8.2 (2004-11-06) [i686-linux]

zsh: abort (core dumped)  ./ruby -de 
% gdb ruby core 
GNU gdb 6.1-debian
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i386-linux"...Using host libthread_db library "/lib/libthread_db.so.1".

Core was generated by `./ruby -de 
def make_unlockable_string
  callcc {|$kk|
    dest = nil
    begin'.
Program terminated with signal 6, Aborted.
Reading symbols from /lib/libdl.so.2...done.
Loaded symbols for /lib/libdl.so.2
Reading symbols from /lib/libcrypt.so.1...done.
Loaded symbols for /lib/libcrypt.so.1
Reading symbols from /lib/libm.so.6...done.
Loaded symbols for /lib/libm.so.6
Reading symbols from /lib/libc.so.6...done.
Loaded symbols for /lib/libc.so.6
Reading symbols from /lib/ld-linux.so.2...done.
Loaded symbols for /lib/ld-linux.so.2
#0  0x4009e6b1 in kill () from /lib/libc.so.6
(gdb) bt
#0  0x4009e6b1 in kill () from /lib/libc.so.6
#1  0x4009e435 in raise () from /lib/libc.so.6
#2  0x4009f978 in abort () from /lib/libc.so.6
#3  0x080cbdf6 in rb_bug (fmt=0x0) at error.c:214
#4  0x080ab592 in sigsegv (sig=11) at signal.c:446
#5  <signal handler called>
#6  0x400e723b in mallopt () from /lib/libc.so.6
#7  0x400e600f in free () from /lib/libc.so.6
#8  0x0806f246 in rb_gc_call_finalizer_at_exit () at gc.c:1850
#9  0x08053d92 in ruby_finalize_1 () at eval.c:1399
#10 0x08053ea3 in ruby_cleanup (ex=1) at eval.c:1434
#11 0x08053fe1 in ruby_stop (ex=0) at eval.c:1465
#12 0x0805404f in ruby_run () at eval.c:1486
#13 0x080521b5 in main (argc=0, argv=0x0, envp=0xbffff7b4) at main.c:46
(gdb) 
-- 
[田中 哲][たなか あきら][Tanaka Akira]