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

[kadir çetinkaya via cfe-commits]

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@@ -44,6 +44,8 @@ struct ParseOptions {
   bool ImportInsertions = false;
 };
 
+class ModulesBuilder;
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kadircet wrote:

again instead of forward decl, can you include the header?

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