diff --git a/libraries/AP_InertialSensor/AP_InertialSensor.cpp b/libraries/AP_InertialSensor/AP_InertialSensor.cpp
index 5ccb40335b..1f8466b287 100644
--- a/libraries/AP_InertialSensor/AP_InertialSensor.cpp
+++ b/libraries/AP_InertialSensor/AP_InertialSensor.cpp
@@ -543,14 +543,14 @@ AP_InertialSensor::detect_backends(void)
                  hal.spi->get_device(HAL_INS_LSM9DS0_G_NAME),
                  hal.spi->get_device(HAL_INS_LSM9DS0_A_NAME)));
 #elif HAL_INS_DEFAULT == HAL_INS_L3G4200D
-    _add_backend(AP_InertialSensor_L3G4200D::probe(*this, hal.i2c_mgr->get_device(HAL_INS_L3G4200D_I2C_BUS, HAL_INS_L3G4200D_I2C_ADDR));
+    _add_backend(AP_InertialSensor_L3G4200D::probe(*this, hal.i2c_mgr->get_device(HAL_INS_L3G4200D_I2C_BUS, HAL_INS_L3G4200D_I2C_ADDR)));
 #elif HAL_INS_DEFAULT == HAL_INS_RASPILOT
     _add_backend(AP_InertialSensor_MPU6000::probe(*this, hal.spi->get_device(HAL_INS_MPU60x0_NAME)));
     _add_backend(AP_InertialSensor_LSM9DS0::probe(*this,
                  hal.spi->get_device(HAL_INS_LSM9DS0_G_NAME),
                  hal.spi->get_device(HAL_INS_LSM9DS0_A_NAME)));
 #elif HAL_INS_DEFAULT == HAL_INS_MPU9250_I2C
-    _add_backend(AP_InertialSensor_MPU9250::probe(*this, hal.i2c_mgr->get_device(HAL_INS_MPU9250_I2C_BUS, HAL_INS_MPU9250_I2C_ADDR));
+    _add_backend(AP_InertialSensor_MPU9250::probe(*this, hal.i2c_mgr->get_device(HAL_INS_MPU9250_I2C_BUS, HAL_INS_MPU9250_I2C_ADDR)));
 #elif HAL_INS_DEFAULT == HAL_INS_QFLIGHT
     _add_backend(AP_InertialSensor_QFLIGHT::detect(*this));
 #elif HAL_INS_DEFAULT == HAL_INS_QURT