One of the most popular state-space reduction techniques for model checking is partial-order reduction (POR). Of the many different POR implementations, stubborn sets are a very versatile variant and have thus seen many different applications over the past 32 years. One of the early stubborn sets works shows how the basic conditions for reduction can be augmented to preserve stutter-trace equivalence, making stubborn sets suitable for model checking of linear-time properties. In this paper, we identify a flaw in the reasoning and show with a counter-example that stutter-trace equivalence is not necessarily preserved. We propose a stronger reduction condition and provide extensive new correctness proofs to ensure the issue is resolved. Furthermore, we analyse in which formalisms the problem may occur. The impact on practical implementations is limited, since they all compute a correct approximation of the theory.

中文翻译：

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保留口吃的部分订单减少的不一致标签问题的详细说明

用于模型检查的最流行的状态空间缩减技术之一是部分顺序缩减（POR）。在许多不同的POR实现中，顽固集是非常通用的变体，因此在过去32年中看到了许多不同的应用。早期的顽固集之一显示了如何减少还原的基本条件以保持口吃轨迹等价，使顽固集适合于线性时间属性的模型检查。在本文中，我们确定了推理中的缺陷，并通过反例表明不一定保留口吃痕迹等效性。我们提出了一个更强的减少条件，并提供了大量新的正确性证明，以确保解决问题。此外，我们分析问题可能出现在哪些形式主义中。