diff --git a/ChangeLog b/ChangeLog
index 4931830434..c65f7e23ca 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Tue Jul  7 03:47:26 2015  Koichi Sasada  <ko1@atdot.net>
+
+	* vm_core.h: remove a useless declaration.
+
 Tue Jul  7 03:33:20 2015  Koichi Sasada  <ko1@atdot.net>
 
 	* vm_core.h: remove rb_iseq_t::klass to reduce dynamic data.
diff --git a/vm_core.h b/vm_core.h
index 48bf223853..390e790592 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -218,8 +218,6 @@ typedef struct rb_iseq_location_struct {
     VALUE first_lineno; /* TODO: may be unsigned short */
 } rb_iseq_location_t;
 
-struct rb_iseq_struct;
-
 struct rb_iseq_struct {
     /***************/
     /* static data */