diff --git a/ghc/lib/std/cbits/openFile.c b/ghc/lib/std/cbits/openFile.c
index f8528a6da7ee32226a6acf211a6221e0bb27cbf2..2491b179ac9ffa62e86689e9a7f682da7e9887b6 100644
--- a/ghc/lib/std/cbits/openFile.c
+++ b/ghc/lib/std/cbits/openFile.c
@@ -1,7 +1,7 @@
 /* 
  * (c) The GRASP/AQUA Project, Glasgow University, 1994-1998
  *
- * $Id: openFile.c,v 1.9 1999/09/19 19:15:26 sof Exp $
+ * $Id: openFile.c,v 1.10 1999/09/30 12:35:04 sof Exp $
  *
  * openFile Runtime Support
  */
@@ -29,7 +29,7 @@
 #include <fcntl.h>
 #endif
 
-#ifdef mingw32_TARGET_OS
+#if defined(mingw32_TARGET_OS) && !defined(O_NOCTTY)
 #define O_NOCTTY 0
 #endif