1 files changed, 1 insertions, 0 deletions
diff --git a/hal/Hal.cpp b/hal/Hal.cpp
index 0ee2d66f4..f88efd6cc 100644
--- a/hal/Hal.cpp
+++ b/hal/Hal.cpp
@@ -587,6 +587,7 @@ UnregisterSensorObserver(SensorType aSensor, ISensorObserver *aObserver) {
   AssertMainThread();
 
   if (!gSensorObservers) {
+    HAL_ERR("Un-registering a sensor when none have been registered");
     return;
   }