* even worse. For now, we just suppress and move on with our lives.
   *
   * - https://github.com/jspecify/jspecify/issues/65
   *
   * - https://github.com/jspecify/jdk/commit/71d826792b8c7ef95d492c50a274deab938f2552
   */
  /*
   * TODO(cpovirk): Is the unchecked cast avoidable? Would System.arraycopy be similarly fast (if

    return longBitsToDouble(significand | ONE_BITS);
  }

  static double bigToDouble(BigInteger x) {
    // This is an extremely fast implementation of BigInteger.doubleValue(). JDK patch pending.
    BigInteger absX = x.abs();
    int exponent = absX.bitLength() - 1;
    // exponent == floor(log2(abs(x)))
    if (exponent < Long.SIZE - 1) {
      return x.longValue();

  protected static String formatFeatureSet(Set<? extends Feature<?>> features) {
    List<String> temp = new ArrayList<>();
    for (Feature<?> feature : features) {
      Object featureAsObject = feature; // to work around bogus JDK warning
      if (featureAsObject instanceof Enum) {
        Enum<?> f = (Enum<?>) featureAsObject;
        temp.add(f.getDeclaringClass().getSimpleName() + "." + feature);
      } else {

   * even worse. For now, we just suppress and move on with our lives.
   *
   * - https://github.com/jspecify/jspecify/issues/65
   *
   * - https://github.com/jspecify/jdk/commit/71d826792b8c7ef95d492c50a274deab938f2552
   */
  /*
   * TODO(cpovirk): Is the unchecked cast avoidable? Would System.arraycopy be similarly fast (if

 * here. Cipher suites that are not available on either Android (through API level 24) or Java
 * (through JDK 9) are omitted for brevity.
 *
 * See [Android SSLEngine][sslengine] which lists the cipher suites supported by Android.
 *
 * See [JDK Providers][oracle_providers] which lists the cipher suites supported by Oracle.
 *

 * finalization to happen. However, a call to {@code System.gc()} is specified to be no more than a
 * hint, so this technique may fail at the whim of the JDK implementation, for example if a user
 * specified the JVM flag {@code -XX:+DisableExplicitGC}. But in practice, it works very well for
 * ordinary tests.
 *

                    builder.add(elements);
                    return builder.build();
                  }
                })
            .named(ImmutableSetTest.class.getName() + ", with JDK builder")
            .withFeatures(
                CollectionSize.ANY,
                CollectionFeature.KNOWN_ORDER,
                CollectionFeature.SERIALIZABLE,
                CollectionFeature.ALLOWS_NULL_QUERIES)

      throw new Error(e);
    }
  }

  /**
   * Returns a sun.misc.Unsafe. Suitable for use in a 3rd party package. Replace with a simple call
   * to Unsafe.getUnsafe when integrating into a jdk.
   *
   * @return a sun.misc.Unsafe
   */
  private static Unsafe getUnsafe() {
    try {
      return Unsafe.getUnsafe();
    } catch (SecurityException tryReflectionInstead) {
    }
    try {

        } catch (Exception // sneaky checked exception
            | Error atomicReferenceFieldUpdaterFailure) {
          // Some Android 5.0.x Samsung devices have bugs in JDK reflection APIs that cause
          // getDeclaredField to throw a NoSuchFieldException when the field is definitely there.
          // For these users fallback to a suboptimal implementation, based on synchronized. This

   * other utilities in this package.
   *
   * <p><b>Note:</b> this method simply delegates to the JDK method {@link Float#compare}. It is
   * provided for consistency with the other primitive types, whose compare methods were not added
   * to the JDK until JDK 7.
   *
   * @param a the first {@code float} to compare
   * @param b the second {@code float} to compare