diff --git a/core/java/android/provider/CalendarContract.java b/core/java/android/provider/CalendarContract.java
index e1aa21e8ea495..8ac1d84e04e4f 100644
--- a/core/java/android/provider/CalendarContract.java
+++ b/core/java/android/provider/CalendarContract.java
@@ -2618,7 +2618,8 @@ public final class CalendarContract {
             intent.setData(ContentUris.withAppendedId(CalendarContract.CONTENT_URI, alarmTime));
             intent.putExtra(ALARM_TIME, alarmTime);
             intent.setFlags(Intent.FLAG_RECEIVER_INCLUDE_BACKGROUND);
-            PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent, 0);
+            PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent,
+                    PendingIntent.FLAG_IMMUTABLE);
             manager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, alarmTime, pi);
         }