diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.cpp b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
index 6769031..53409d1 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
@@ -376,7 +376,7 @@
                     config.ydpi = values[i] / 1000.0f;
                     break;
                 default:
-                    ALOG_ASSERT(false, "unknown display attribute[%d] %#x",
+                    ALOG_ASSERT(false, "unknown display attribute[%zu] %#x",
                             i, DISPLAY_ATTRIBUTES[i]);
                     break;
             }