diff --git a/ChangeLog b/ChangeLog
index 17a04c9ab9..8ad03354a0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat Nov 24 10:59:14 2012  KOSAKI Motohiro  <kosaki.motohiro@gmail.com>
+
+	* thread.c (thread_create_core): don't use th->thread_id before
+	  initialized.
+
 Sat Nov 24 00:00:53 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* ruby.c (proc_options, process_options, ruby_process_options): take
diff --git a/thread.c b/thread.c
index 159dbffc87..64eaadc9b5 100644
--- a/thread.c
+++ b/thread.c
@@ -570,13 +570,12 @@ thread_create_core(VALUE thval, VALUE args, VALUE (*fn)(ANYARGS))
     native_mutex_initialize(&th->interrupt_lock);
 
     /* kick thread */
-    st_insert(th->vm->living_threads, thval, (st_data_t) th->thread_id);
     err = native_thread_create(th);
     if (err) {
-	st_delete_wrap(th->vm->living_threads, th->self);
 	th->status = THREAD_KILLED;
 	rb_raise(rb_eThreadError, "can't create Thread (%d)", err);
     }
+    st_insert(th->vm->living_threads, thval, (st_data_t) th->thread_id);
     return thval;
 }