[lld] [lld][ELF] Implement merged .debug_names section. (PR #86508)

[Fangrui Song via llvm-commits]

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@@ -788,6 +792,136 @@ class RelroPaddingSection final : public SyntheticSection {
   void writeTo(uint8_t *buf) override {}
 };
 
+class DebugNamesSection final : public SyntheticSection {
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MaskRay wrote:

There are a lot of `ELFT` in member functions. Seems better to make the class `ELFT`, or follow `RelocationBaseSection`: non-template base class with ELFT derived class.

https://github.com/llvm/llvm-project/pull/86508