[clang] [docs] Asking to test serialization/deserialization for new C++ feature (PR #200994)

[Chuanqi Xu via cfe-commits]

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@@ -3908,6 +3908,76 @@ directives:
     //   since-cxx17-note@#cwg92-p {{use 'noexcept(false)' instead}}
     // cxx98-14-error@#cwg92-p {{target exception specification is not superset of source}}
 
+
+Testing Modules (Serialization/Deserialization) When implementing a new C++ syntax
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ChuanqiXu9 wrote:

The motivation case is https://github.com/llvm/llvm-project/issues/195350 . The #embed doesn't have an straight forward interaction, but we just forgot to test it and users meet the problem. The design of modules requires all (or almost) features need to be serialized and deserialized. Then the doc change is about that.

https://github.com/llvm/llvm-project/pull/200994