diff --git a/libraries/AP_InertialSensor/AP_InertialSensor_L3GD20.cpp b/libraries/AP_InertialSensor/AP_InertialSensor_L3GD20.cpp
index 6a443398e3..07dd5356f8 100644
--- a/libraries/AP_InertialSensor/AP_InertialSensor_L3GD20.cpp
+++ b/libraries/AP_InertialSensor/AP_InertialSensor_L3GD20.cpp
@@ -36,7 +36,7 @@
  ****************************************************************************/
 
 #include <AP_HAL.h>
-#if NOT_YET
+#if defined(NOT_YET)
 
 #include "AP_InertialSensor_L3GD20.h"
 
diff --git a/libraries/AP_InertialSensor/AP_InertialSensor_LSM303D.cpp b/libraries/AP_InertialSensor/AP_InertialSensor_LSM303D.cpp
index b6c6b7d341..5a3bb796c6 100644
--- a/libraries/AP_InertialSensor/AP_InertialSensor_LSM303D.cpp
+++ b/libraries/AP_InertialSensor/AP_InertialSensor_LSM303D.cpp
@@ -1,6 +1,6 @@
 /// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
 
-#if NOT_YET
+#if defined(NOT_YET)
 
 /****************************************************************************
  *