return -1;
      } else if (right == null) {
        return 1;
      }
      int leftCode = identityHashCode(left);
      int rightCode = identityHashCode(right);
      if (leftCode != rightCode) {
        return leftCode < rightCode ? -1 : 1;
      }

      // identityHashCode collision (rare, but not as rare as you'd think)
      int result = getUid(left).compareTo(getUid(right));

        return -1;
      } else if (right == null) {
        return 1;
      }
      int leftCode = identityHashCode(left);
      int rightCode = identityHashCode(right);
      if (leftCode != rightCode) {
        return leftCode < rightCode ? -1 : 1;
      }

      // identityHashCode collision (rare, but not as rare as you'd think)
      int result = getUid(left).compareTo(getUid(right));

import static com.google.common.util.concurrent.SequentialExecutor.WorkerRunningState.QUEUING;
import static com.google.common.util.concurrent.SequentialExecutor.WorkerRunningState.RUNNING;
import static java.lang.System.identityHashCode;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.Preconditions;
import com.google.errorprone.annotations.concurrent.GuardedBy;

   */
  public static Equivalence<Object> equals() {
    return Equals.INSTANCE;
  }

  /**
   * Returns an equivalence that uses {@code ==} to compare values and {@link
   * System#identityHashCode(Object)} to compute the hash code. {@link Equivalence#equivalent}
   * returns {@code true} if {@code a == b}, including in the case that a and b are both null.
   *
   * @since 13.0
   * @since 4.0 (in Equivalences)

   */
  public static Equivalence<Object> equals() {
    return Equals.INSTANCE;
  }

  /**
   * Returns an equivalence that uses {@code ==} to compare values and {@link
   * System#identityHashCode(Object)} to compute the hash code. {@link Equivalence#equivalent}
   * returns {@code true} if {@code a == b}, including in the case that a and b are both null.
   *
   * @since 13.0
   * @since 4.0 (in Equivalences)

          && hashCodeInsensitiveToArgReference(
              factory, args, i, generateDummyArg(param, newFreshValueGenerator()))) {
        // If the implementation uses identityHashCode(), referential equality is
        // probably intended. So no point in using an equal-but-different factory argument.
        // We check twice to avoid confusion caused by accidental hash collision.

import static com.google.common.util.concurrent.Platform.rethrowIfErrorOtherThanStackOverflow;
import static java.lang.Integer.toHexString;
import static java.lang.System.identityHashCode;
import static java.util.Objects.requireNonNull;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import static java.util.logging.Level.SEVERE;

import com.google.common.annotations.GwtCompatible;

          && hashCodeInsensitiveToArgReference(
              factory, args, i, generateDummyArg(param, newFreshValueGenerator()))) {
        // If the implementation uses identityHashCode(), referential equality is
        // probably intended. So no point in using an equal-but-different factory argument.
        // We check twice to avoid confusion caused by accidental hash collision.

    for (int i = 0; i < 50; i++) {
      list.add(i);
    }

    Ordering<Object> arbitrary =
        new ArbitraryOrdering() {
          @Override
          int identityHashCode(Object object) {
            return ((Integer) object) % 5; // fake tons of collisions!
          }
        };

    // Don't let the elements be in such a predictable order

    for (int i = 0; i < 50; i++) {
      list.add(i);
    }

    Ordering<Object> arbitrary =
        new ArbitraryOrdering() {
          @Override
          int identityHashCode(Object object) {
            return ((Integer) object) % 5; // fake tons of collisions!
          }
        };

    // Don't let the elements be in such a predictable order