diff --git a/ChangeLog b/ChangeLog
index 50be216f14..3519748307 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Sat Dec 22 14:02:58 2007  Koichi Sasada  <ko1@atdot.net>
+
+	* array.c (rb_ary_permutation): add volatile to avoid GC problem.
+
 Sat Dec 22 11:47:42 2007  Koichi Sasada  <ko1@atdot.net>
 
 	* eval.c (rb_obj_instance_eval): use class of immediate objects.
diff --git a/array.c b/array.c
index 0afefb685d..741887bcba 100644
--- a/array.c
+++ b/array.c
@@ -3069,9 +3069,9 @@ rb_ary_permutation(int argc, VALUE *argv, VALUE ary)
 	}
     }
     else {             /* this is the general case */
-	VALUE t0 = tmpbuf(n,sizeof(long));
+	volatile VALUE t0 = tmpbuf(n,sizeof(long));
 	long *p = (long*)RSTRING_PTR(t0);
-	VALUE t1 = tmpbuf(n,sizeof(int));
+	volatile VALUE t1 = tmpbuf(n,sizeof(int));
 	int *used = (int*)RSTRING_PTR(t1);
 	VALUE ary0 = ary_make_shared(ary); /* private defensive copy of ary */