[clang] [clang][deps] Skip slow `UNHASHED_CONTROL_BLOCK` records (PR #69975)

[Ben Langmuir via cfe-commits]

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@@ -1212,9 +1212,12 @@ void ASTWriter::writeUnhashedControlBlock(Preprocessor &PP,
     Record.clear();
   }
 
+  const auto &HSOpts = PP.getHeaderSearchInfo().getHeaderSearchOpts();
+
   // Diagnostic options.
   const auto &Diags = Context.getDiagnostics();
   const DiagnosticOptions &DiagOpts = Diags.getDiagnosticOptions();
+  if (!HSOpts.ModulesSkipDiagnosticOptions) {
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benlangmuir wrote:

Now that we're doing this upstream we should re-indent this code.

https://github.com/llvm/llvm-project/pull/69975