[clang-tools-extra] [clangd] [C++20] [Modules] Support code complete for C++20 modules (PR #110083)

[kadir çetinkaya via cfe-commits]

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@@ -52,6 +52,11 @@ struct CodeCompleteOptions {
   /// For example, private members are usually inaccessible.
   bool IncludeIneligibleResults = false;
 
+  /// Force sema to load decls from preamble even if an index is provided.
+  /// This is helpful for cases the index can't provide symbols, e.g., the
+  /// unsupported yet modules.
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kadircet wrote:

`e.g. with experimental c++20 modules`

https://github.com/llvm/llvm-project/pull/110083