diff --git a/ChangeLog b/ChangeLog
index e6076b3e61..8b96d58d5c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Fri Jul 26 18:30:14 2013  Koichi Sasada  <ko1@atdot.net>
+
+	* array.c (ary_memcpy): cast to int to suppress a warning.
+
 Fri Jul 26 18:21:58 2013  Koichi Sasada  <ko1@atdot.net>
 
 	* array.c (ary_memcpy): try to enable optimization.
diff --git a/array.c b/array.c
index 8ab71289a2..3d999e8879 100644
--- a/array.c
+++ b/array.c
@@ -69,7 +69,7 @@ ary_memcpy(VALUE ary, long beg, long argc, const VALUE *argv)
 {
 #if 1
     if (OBJ_PROMOTED(ary)) {
-	if (argc > (128/sizeof(VALUE)) /* is magic number (cache line size) */) {
+	if (argc > (int)(128/sizeof(VALUE)) /* is magic number (cache line size) */) {
 	    rb_gc_writebarrier_remember_promoted(ary);
 	    RARRAY_PTR_USE(ary, ptr, {
 		MEMCPY(ptr+beg, argv, VALUE, argc);