2 files changed, 9 insertions, 1 deletions
diff --git a/ChangeLog b/ChangeLog
index f40136de1f..b0803ab704 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Sun Aug 16 17:24:10 2015  Kazuki Tsujimoto  <kazuki@callcc.net>
+
+	* gc.c (gc_mark_children): check if RCLASS_EXT is valid
+	  before marking. This fixes the following test failure
+	  introduced in r51126:
+
+	    make test-all TESTOPTS='--gc-stress ruby/test_refinement.rb'
+
 Sat Aug 15 10:51:08 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* ext/win32/lib/win32/registry.rb (API#SetValue): data size should
diff --git a/gc.c b/gc.c
index 2aaf630b22..525c83a229 100644
--- a/gc.c
+++ b/gc.c
@@ -4331,8 +4331,8 @@ gc_mark_children(rb_objspace_t *objspace, VALUE obj)
 	if (FL_TEST(obj, RICLASS_IS_ORIGIN)) {
 	    mark_m_tbl(objspace, RCLASS_M_TBL(obj));
 	}
-	mark_m_tbl(objspace, RCLASS_CALLABLE_M_TBL(obj));
 	if (!RCLASS_EXT(obj)) break;
+	mark_m_tbl(objspace, RCLASS_CALLABLE_M_TBL(obj));
 	gc_mark(objspace, RCLASS_SUPER((VALUE)obj));
 	break;