[clang] [Serialization] [ASTWriter] Try to not record namespace as much as possible (PR #179178)

[Chuanqi Xu via cfe-commits]

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@@ -4817,10 +4826,8 @@ void ASTWriter::GenerateNameLookupTable(
     Generator.insert(ConversionDecls.front()->getDeclName(),
                      Trait.getData(ConversionDecls), Trait);
 
-  // Create the on-disk hash table. Also emit the existing imported and
-  // merged table if there is one.
-  auto *Lookups = Chain ? Chain->getLoadedLookupTables(DC) : nullptr;
-  Generator.emit(LookupTable, Trait, Lookups ? &Lookups->Table : nullptr);
+  // Create the on-disk hash table.
+  Generator.emit(LookupTable, Trait, nullptr);
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ChuanqiXu9 wrote:

Done or not valid now.

https://github.com/llvm/llvm-project/pull/179178