[clang] [WIP] Implement `print-deserialized-declarations` flag to dump source… (PR #133910)

[Viktoriia Bakalova via cfe-commits]

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@@ -7968,6 +7968,10 @@ def print_dependency_directives_minimized_source : Flag<["-"],
   "print-dependency-directives-minimized-source">,
   HelpText<"Print the output of the dependency directives source minimizer">;
 }
+def print_deserialized_declarations : Joined<["-"],
+  "print-deserialized-declarations-path=">,
+  HelpText<"Print traces of deserialized declarations to aid debugging and minimization">,
+  MarshallingInfoString<FrontendOpts<"PrintDeserializedDeclarationsPath">>;
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VitaNuo wrote:

AFAICT it's already a CC1 option.

https://github.com/llvm/llvm-project/pull/133910