[clang] [WIP][Modules] Delay deserialization of preferred_name attribute at r… (PR #122726)

[Ilya Biryukov via cfe-commits]

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@@ -3134,6 +3139,17 @@ Attr *ASTRecordReader::readAttr() {
   // Kind is stored as a 1-based integer because 0 is used to indicate a null
   // Attr pointer.
   auto Kind = static_cast<attr::Kind>(V - 1);
+  if (Kind == attr::PreferredName && D != nullptr) {
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ilya-biryukov wrote:

Could you add a comment explaining why we need to defer some attribute?

https://github.com/llvm/llvm-project/pull/122726