diff --git a/ChangeLog b/ChangeLog
index 42807550c0..dd5cab6bea 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,4 +1,6 @@
-Fri Nov  9 23:02:25 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+Fri Nov  9 23:05:06 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* random.c (BYTE_ORDER): define using configured WORDS_BIGENDIAN.
 
 	* siphash.c (sip_init_state): use union to suppress warnings by gcc
 	  4.7.
diff --git a/random.c b/random.c
index 196fd14f1e..e7e4ea7c24 100644
--- a/random.c
+++ b/random.c
@@ -1328,6 +1328,19 @@ random_s_rand(int argc, VALUE *argv, VALUE obj)
 
 #define SIP_HASH_STREAMING 0
 #define sip_hash24 ruby_sip_hash24
+#if !defined _WIN32 && !defined BYTE_ORDER
+# ifdef WORDS_BIGENDIAN
+#   define BYTE_ORDER BIG_ENDIAN
+# else
+#   define BYTE_ORDER LITTLE_ENDIAN
+# endif
+# ifndef LITTLE_ENDIAN
+#   define LITTLE_ENDIAN 1234
+# endif
+# ifndef BIG_ENDIAN
+#   define BIG_ENDIAN    4321
+# endif
+#endif
 #include "siphash.c"
 
 static st_index_t hashseed;