HermitCrab analysis can spin on simultaneous rewrites with incompatible environments

未关闭
  • 哪里不对？
#623 0 条评论 0 个 reaction 已指派 0 人 在 GitHub 查看

维护者通常 1 天内回复

@johnml1135 已经在做这个了。

开始于 2026年11月9日。

  • #624 来自 @johnml1135 —— 未关闭

评估

难度
4/5
预计耗时
3-5 天
新手友好度
58/100
Issue 类型
缺陷
描述清晰度
描述清楚
活跃度
活跃
技术栈
csharp
领域
backend, testing-qa

调研方向

Start with AnalysisRewriteRule.cs around the SelfOpaquing selection and reapplication loop, then inspect SimultaneousPhonologicalPatternRule.cs and its no-match behavior. Add regression cases for the three reduced shapes in the issue and check that reapplication stops when a simultaneous rule makes no change. The issue does not identify test file paths, so locate the existing analysis rewrite tests before adding cases; verify the cases terminate and produce the expected parses.

由索引模型根据 Issue 内容生成。

描述

HermitCrab’s C# analysis parser can hang indefinitely in a simultaneous rewrite when a replacement segment conflicts with an environment segment, consuming one CPU core; the pinned hc.dll reproduced all three reported shapes.

  • Minimal segment case: one-feature t → d / _ a, underlying ta, parse da.
  • Alpha-input case: input [nasal:+, α(place)], output m, environment _ p with p nasal−; parse prefixed mp.
  • Underlying realization case: one rule ʔ → - / _ V[+vocalic], underlying ʔa, parse -a.
  • Suspected source: AnalysisRewriteRule.Apply selects an unbounded SelfOpaquing loop when RHS and environment feature structures are incompatible; SimultaneousPhonologicalPatternRule.Apply returns a word even when it finds no matches.
  • Not known: whether synthesis has the same reapplication behavior.

Next: add regression cases for these reduced shapes and make self-opaquing reapplication stop when the simultaneous rule makes no change.

Reproduction and evidence

Replayed with the Release HermitCrab CLI from Machine commit 4d9b454d42a0da35e058641a65596339a79d115b using dotnet hc.dll -i <grammar.xml> -s <script>. The three original inputs each timed out at 45 seconds; all reduced shapes timed out at 10 seconds. Each timeout used a captured process PID and direct SIGTERM. Reduced runs sampled 107–112% CPU on one process. Compatible-output, no-environment, and feature-removal controls completed promptly.

At the pin, AnalysisRewriteRule.cs:47-69 selects SelfOpaquing after the RHS/environment FeatureStruct.IsUnifiable check fails; :166-173 has no progress or termination guard. SimultaneousPhonologicalPatternRule.cs:22-35 always returns the input word, including when Matcher.AllMatches produces no applicable match. The reduced alpha-input case also hangs after α is removed while retaining the feature-bearing input class, and the glottal case hangs with a single rule, so neither α nor the original rule chain is necessary to the loop.

The pin-matched driver was absent from the exact-pin worktree, so the Tool Release project was built from an exact-pin source archive (SHA-256 of resulting hc.dll: 9cd575be98ddb4e9e32e63114ee699c94d7a395af2074ad15f1557a272404964). The related loop files are unchanged in locally fetched Machine origin/master 9f284a3cc4d5e2c5896f885ba1103fb30594b1e8.

Found while comparing HC-Rust (PanGloss) with pinned hc.dll; PanGloss answers all three in about 1 ms.

主要语言
C#
星标
29
派生
16
平均合并
5 天 11 小时
30 天内合并 PR
15

环境准备

  • 没有 Dockerfile 或 Docker Compose 文件
  • 有 Pull Request 模板
  • 没有贡献指南

从这里开始

  1. 先读完整个 Issue，再读项目的贡献指南。
  2. 在 Issue 下留言说明你要接手 —— 这能避免两个人做同样的事。
  3. Fork 仓库，在一个分支上完成修改。
  4. 提交 Pull Request，并在描述里引用这个 Issue 编号。

sillsdev/machine 的其他 Issue

查看 sillsdev/machine 的全部 Issue

相似的 Issue

更多 C# Issue

把新 issue 发到你的邮箱

精选适合新手参与的 GitHub issue 摘要。