From 8f032ad122df43b1f74be4c2ec47a58310bb2f4e Mon Sep 17 00:00:00 2001
From: 3d-gussner <3d.gussner@gmail.com>
Date: Fri, 8 Jun 2018 09:44:58 +0200
Subject: [PATCH] Fix MK3 compilation issue with Arduino 1.8.x

see https://github.com/prusa3d/Prusa-Firmware/issues/614#issuecomment-385034066
---
 Firmware/xyzcal.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Firmware/xyzcal.cpp b/Firmware/xyzcal.cpp
index ed3d3210dd..a59f489783 100644
--- a/Firmware/xyzcal.cpp
+++ b/Firmware/xyzcal.cpp
@@ -32,7 +32,7 @@
 
 #define _PI 3.14159265F
 
-extern long count_position[NUM_AXIS];
+extern volatile long count_position[NUM_AXIS];
 
 uint8_t check_pinda_0();
 uint8_t check_pinda_1();