[clang-tools-extra] [clangd] Support suppressions for driver diagnostics (PR #182912)

[Aleksandr Platonov via cfe-commits]

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@@ -183,7 +183,7 @@ class StoreDiags : public DiagnosticConsumer {
 /// Determine whether a (non-clang-tidy) diagnostic is suppressed by config.
 bool isDiagnosticSuppressed(const clang::Diagnostic &Diag,
                             const llvm::StringSet<> &Suppressed,
-                            const LangOptions &);
+                            const std::optional<LangOptions> &);
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ArcsinX wrote:

Sorry I didn't notice this initially. This function is only used within Diagnostics.cpp. So we can remove it from Diagnostics.h and move it to an anonymous namespace within Diagnostics.cpp or make it static.

https://github.com/llvm/llvm-project/pull/182912