diff --git a/ChangeLog b/ChangeLog
index a7cac76a14..cecf793dfe 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Wed Jun 17 11:39:15 2015  Koichi Sasada  <ko1@atdot.net>
+
+	* vm_insnhelper.c (lep_svar_set): add WBs.
+
 Tue Jun  9 16:29:49 2015  Eric Wong  <e@80x24.org>
 
 	* ext/socket/ancdata.c: use RB_GC_GUARD instead of volatile
diff --git a/version.h b/version.h
index 613442b4f1..0cd0bbdfba 100644
--- a/version.h
+++ b/version.h
@@ -1,10 +1,10 @@
 #define RUBY_VERSION "2.1.7"
-#define RUBY_RELEASE_DATE "2015-06-09"
-#define RUBY_PATCHLEVEL 366
+#define RUBY_RELEASE_DATE "2015-06-17"
+#define RUBY_PATCHLEVEL 367
 
 #define RUBY_RELEASE_YEAR 2015
 #define RUBY_RELEASE_MONTH 6
-#define RUBY_RELEASE_DAY 9
+#define RUBY_RELEASE_DAY 17
 
 #include "ruby/version.h"
 
diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index 20dc63f1e0..7a081d2b74 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -200,16 +200,16 @@ lep_svar_set(rb_thread_t *th, VALUE *lep, rb_num_t key, VALUE val)
 
     switch (key) {
       case 0:
-	svar->u1.value = val;
+	RB_OBJ_WRITE(svar, &svar->u1.value, val);
 	return;
       case 1:
-	svar->u2.value = val;
+	RB_OBJ_WRITE(svar, &svar->u2.value, val);
 	return;
       default: {
 	VALUE ary = svar->u3.value;
 
 	if (NIL_P(ary)) {
-	    svar->u3.value = ary = rb_ary_new();
+	    RB_OBJ_WRITE(svar, &svar->u3.value, ary = rb_ary_new());
 	}
 	rb_ary_store(ary, key - DEFAULT_SPECIAL_VAR_COUNT, val);
       }