From b9418439b94d6d7ba1b700d16c78888e458d4102 Mon Sep 17 00:00:00 2001
From: Scott Lahteine <github@thinkyhead.com>
Date: Fri, 8 Jun 2018 19:58:43 -0500
Subject: [PATCH] Prevent MB false-positive on bad board name

---
 Marlin/src/core/boards.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Marlin/src/core/boards.h b/Marlin/src/core/boards.h
index b4aa649094..a6d1ec27e1 100644
--- a/Marlin/src/core/boards.h
+++ b/Marlin/src/core/boards.h
@@ -226,6 +226,6 @@
 #define BOARD_THE_BORG         1860   // THE-BORG (Power outputs: Hotend0, Hotend1, Bed, Fan)
 
 
-#define MB(board) (MOTHERBOARD==BOARD_##board)
+#define MB(board) (defined(BOARD_##board) && MOTHERBOARD==BOARD_##board)
 
 #endif // __BOARDS_H