diff --git a/ChangeLog b/ChangeLog
index 87ca3697cc..df3cec8270 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Tue Jun 18 04:20:18 2013  Koichi Sasada  <ko1@atdot.net>
+
+	* gc.c (gc_mark_children): don't need to care about T_ZOMBIE here.
+
 Mon Jun 17 22:16:02 2013  Kazuki Tsujimoto  <kazuki@callcc.net>
 
 	* test/ruby/test_proc.rb (TestProc#test_block_given_method_to_proc):
diff --git a/gc.c b/gc.c
index c9db573406..530a232fd6 100644
--- a/gc.c
+++ b/gc.c
@@ -3341,7 +3341,6 @@ gc_mark_children(rb_objspace_t *objspace, VALUE ptr)
 
       case T_FLOAT:
       case T_BIGNUM:
-      case T_ZOMBIE:
 	break;
 
       case T_MATCH: