*   operations to distinguish between zero and absent. If we do this, then perhaps we should add
   *   replace(key, long).
   *
   * - Introduce a special-value private static final AtomicLong that would have the meaning of
   *   removal-in-progress, and rework all operations to properly distinguish between zero and
   *   absent.
   */

  /**

    static final Logger log = Logger.getLogger(ExecutionListCAS.class.getName());

    private static final Unsafe UNSAFE;
    private static final long HEAD_OFFSET;

    /**
     * A special instance of {@link RunnableExecutorPair} that is used as a sentinel value for the
     * bottom of the stack.
     */
    private static final RunnableExecutorPair NULL_PAIR = new RunnableExecutorPair(null, null);

# Recommended: use a local+remote cache.
#
#   Bazel will cache your builds in tensorflow/build_output/cache,
#   and will also try using public build cache results to speed up
#   your builds. This usually saves a lot of time, especially when
#   re-running tests. However, note that:
#
#    - New environments like new CUDA versions, changes to manylinux,
#      compilers, etc. can cause undefined behavior such as build failures

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