diff --git a/services/surfaceflinger/DisplayDevice.cpp b/services/surfaceflinger/DisplayDevice.cpp
index 2753f11..9772f9a 100644
--- a/services/surfaceflinger/DisplayDevice.cpp
+++ b/services/surfaceflinger/DisplayDevice.cpp
@@ -160,7 +160,7 @@
 }
 
 bool DisplayDevice::isValid() const {
-    return mFlinger != NULL;
+    return mFlinger != nullptr;
 }
 
 int DisplayDevice::getWidth() const {