在 debug 和 release 下解析结果不一致

请教一下，为什么定义 class 的属性是 let 后，在 debug 和 release 下表现不一样，debug 下能正常解析，release 下却不能正常解析。

Start by reproducing the reported difference with a class property declared as let in both debug and release builds. Compare the parsing or deserialization results and identify the release-only behavior; done means the same input is handled consistently in both configurations. The issue names no files, tests, or entry points, so project-wide investigation is required.

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