[clang-tools-extra] [clangd] [C++20] [Modules] Introduce initial support for C++20 Modules (PR #66462)

[Sam McCall via cfe-commits]

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@@ -104,6 +107,8 @@ struct PreambleData {
   IncludeStructure Includes;
   // Captures #include-mapping information in #included headers.
   std::shared_ptr<const include_cleaner::PragmaIncludes> Pragmas;
+  // Information about module files for this preamble.
+  std::optional<PrerequisiteModules> DependentModulesInfo;
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sam-mccall wrote:

nit: drop `Info` here too

https://github.com/llvm/llvm-project/pull/66462