diff -r 7322c48a84cf -r 6252605fb005 src/java.base/share/classes/java/util/concurrent/atomic/LongAccumulator.java
--- a/src/java.base/share/classes/java/util/concurrent/atomic/LongAccumulator.java	Thu Oct 17 07:31:35 2019 +0800
+++ b/src/java.base/share/classes/java/util/concurrent/atomic/LongAccumulator.java	Wed Oct 16 16:55:52 2019 -0700
@@ -82,6 +82,7 @@
 public class LongAccumulator extends Striped64 implements Serializable {
     private static final long serialVersionUID = 7249069246863182397L;
 
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private final LongBinaryOperator function;
     private final long identity;
 
@@ -239,6 +240,7 @@
          * The function used for updates.
          * @serial
          */
+        @SuppressWarnings("serial") // Not statically typed as Serializable
         private final LongBinaryOperator function;
 
         /**