diff --git a/ChangeLog b/ChangeLog
index e2852fd4ad..d9bc19ac2e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun Oct 23 08:01:29 2011  Tanaka Akira  <akr@fsij.org>
+
+	* io.c (rb_fd_set_cloexec): set close-on-exec flag only if F_GETFD is
+	  defined.  reported by Luis Lavena.  [ruby-core:40281] [Bug #5470]
+
 Sat Oct 22 19:48:50 2011  Tanaka Akira  <akr@fsij.org>
 
 	* test/openssl/test_ssl.rb (test_multibyte_read_write): start server
diff --git a/io.c b/io.c
index c4980a2c8b..c9a33f3aad 100644
--- a/io.c
+++ b/io.c
@@ -159,6 +159,8 @@ rb_update_max_fd(int fd)
 
 void rb_fd_set_cloexec(int fd)
 {
+  /* MinGW don't have F_GETFD and FD_CLOEXEC.  [ruby-core:40281] */
+#ifdef F_GETFD
     int flags, ret;
     flags = fcntl(fd, F_GETFD); /* should not fail except EBADF. */
     if (flags == -1) {
@@ -173,6 +175,7 @@ void rb_fd_set_cloexec(int fd)
             }
         }
     }
+#endif
     if (max_file_descriptor < fd) max_file_descriptor = fd;
 }