Cannot build the document on Mac

[HideakiImamura]

What is an issue?

Problem

I cannot build the document on my MacBook, and my colleagues also cannot. It might be the problem due to the dependencies, but I have no exact idea how to fix this. Concretely, the build stops at the execution of optuna.visualization.matplotlib.plot_terminator_improvement.

What should be done

The following command should be finished without any errors.

cd docs
make html

Environment

Chip: Apple M2 OS: Sonoma 14.4.1 Python: 3.9.6 Optuna: current master https://github.com/optuna/optuna/commit/98d44447cb557a7654ea92f5ea94059c2d2fc2b1 Sphinx : 7.3.7

Log

(venv) mamu@hideakis-mbp docs % make html
Running Sphinx v7.3.7
Using Sphinx-Gallery to convert rst text blocks to markdown for .ipynb files.
[autosummary] generating autosummary for: faq.rst, index.rst, installation.rst, license_thirdparty.rst, privacy.rst, reference/artifacts.rst, reference/cli.rst, reference/distributions.rst, reference/exceptions.rst, reference/generated/optuna.TrialPruned.rst, ..., tutorial/20_recipes/007_optuna_callback.rst, tutorial/20_recipes/008_specify_params.rst, tutorial/20_recipes/009_ask_and_tell.rst, tutorial/20_recipes/010_reuse_best_trial.rst, tutorial/20_recipes/011_journal_storage.rst, tutorial/20_recipes/012_artifact_tutorial.rst, tutorial/20_recipes/013_wilcoxon_pruner.rst, tutorial/20_recipes/index.rst, tutorial/20_recipes/sg_execution_times.rst, tutorial/index.rst
... (omitted)
[I 2024-05-28 15:49:13,556] Trial 29 finished with value: 0.3988888888888889 and parameters: {'reg_alpha': 3.678682178991996, 'reg_lambda': 0.3774170267659814, 'num_leaves': 149, 'colsample_bytree': 0.41211293837374274, 'subsample': 0.6490900435795488, 'subsample_freq': 7, 'min_child_samples': 70}. Best is trial 27 with value: 0.3314285714285714.
<string>:27: ExperimentalWarning:

plot_terminator_improvement is experimental (supported from v3.2.0). The interface can change in the future.

/Users/mamu/Work-and-Study/optuna/optuna/visualization/_terminator_improvement.py:131: ExperimentalWarning:

RegretBoundEvaluator is experimental (supported from v3.2.0). The interface can change in the future.

/Users/mamu/Work-and-Study/optuna/optuna/visualization/_terminator_improvement.py:136: ExperimentalWarning:

CrossValidationErrorEvaluator is experimental (supported from v3.2.0). The interface can change in the future.

  0%|                                                                                     | 0/30 [00:00<?, ?it/s]make: *** [html] Segmentation fault: 11
/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/multiprocessing/resource_tracker.py:216: UserWarning: resource_tracker: There appear to be 1 leaked semaphore objects to clean up at shutdown
  warnings.warn('resource_tracker: There appear to be %d '