diff --git a/contrib/pg_upgrade/pg_upgrade.h b/contrib/pg_upgrade/pg_upgrade.h
index 3c3ca6daf6a..83d3e6cfb54 100644
--- a/contrib/pg_upgrade/pg_upgrade.h
+++ b/contrib/pg_upgrade/pg_upgrade.h
@@ -54,6 +54,17 @@
 #define EXE_EXT				".exe"
 #endif
 
+#if defined(WIN32) && !defined(__CYGWIN__)
+
+		/*
+		 * XXX This does not work for all terminal environments or for output
+		 * containing non-ASCII characters; see comments in simple_prompt().
+		 */
+#define DEVTTY	"con"
+#else
+#define DEVTTY	"/dev/tty"
+#endif
+
 #define CLUSTERNAME(cluster)	((cluster) == CLUSTER_OLD ? "old" : "new")
 
 #define atooid(x)  ((Oid) strtoul((x), NULL, 10))