}

  /** {@link AtomicHelper} based on {@link VarHandle}. */
  @J2ObjCIncompatible
  // We use this class only after confirming that VarHandle is available at runtime.
  @SuppressWarnings("Java8ApiChecker")
  @IgnoreJRERequirement
  private static final class VarHandleAtomicHelper extends AtomicHelper {
    static final VarHandle waiterThreadUpdater;
    static final VarHandle waiterNextUpdater;

      }
    },
    @J2ObjCIncompatible
    CRC_32C("Hashing.crc32c()") {
      // Crc32CSupplier.pickFunction uses this only when it finds that CRC32C is available.
      @SuppressWarnings("Java8ApiChecker")
      @IgnoreJRERequirement
      @Override
      public Checksum get() {
        return new CRC32C();
      }
    },
    ADLER_32("Hashing.adler32()") {
      @Override