diff --git a/ChangeLog b/ChangeLog
index 54a533ccbd..3002fad9ce 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Aug  4 11:30:36 2011  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* include/ruby/missing.h: define __syscall on OpenBSD as r32702.
+
 Thu Aug  4 03:02:54 2011  Aaron Patterson <aaron@tenderlovemaking.com>
 
 	* tool/rbinstall.rb: use rubygems to load gemspecs, copy actual
diff --git a/include/ruby/missing.h b/include/ruby/missing.h
index bded5521d1..e3adc5ce4e 100644
--- a/include/ruby/missing.h
+++ b/include/ruby/missing.h
@@ -51,8 +51,8 @@ struct timezone {
 };
 #endif
 
-#if defined(HAVE___SYSCALL) && defined(__APPLE__)
-/* Mac OS X has __syscall but doen't defined in headers */
+#if defined(HAVE___SYSCALL) && (defined(__APPLE__) || defined(__OpenBSD__))
+/* Mac OS X and OpenBSD has __syscall but doen't defined in headers */
 off_t __syscall(quad_t number, ...);
 #endif