diff --git a/ChangeLog b/ChangeLog
index efc4976f21..e82caf06b2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Tue May  7 12:09:29 2013  Tanaka Akira  <akr@fsij.org>
+
+	* ext/socket/extconf.rb: Set close_fds false for Cygwin.
+	  Cygwin doesn't support fd passing.
+	  This enables socket extension library cross-compilable by default.
+
 Tue May  7 12:07:35 2013  Tanaka Akira  <akr@fsij.org>
 
 	* pack.c (swap32): Don't redefine it if it is already defined.
diff --git a/ext/socket/extconf.rb b/ext/socket/extconf.rb
index 66fb06d7c6..29e401a5ba 100644
--- a/ext/socket/extconf.rb
+++ b/ext/socket/extconf.rb
@@ -253,6 +253,10 @@ def test_recvmsg_with_msg_peek_creates_fds(headers)
     # [ruby-dev:44189]
     # http://bugs.ruby-lang.org/issues/5075
     close_fds = false
+  when /cygwin/
+    # Cygwin doesn't support fd passing.
+    # http://cygwin.com/ml/cygwin/2003-09/msg01808.html
+    close_fds = false
   else
     close_fds = nil
   end