[clang] [clang-tools-extra] [Clang] Add __type_list_dedup builtin to deduplicate types in template arguments (PR #106730)

[Nikolas Klauser via cfe-commits]

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@@ -309,7 +309,10 @@ enum BuiltinTemplateKind : int {
   BTK__make_integer_seq,
 
   /// This names the __type_pack_element BuiltinTemplateDecl.
-  BTK__type_pack_element
+  BTK__type_pack_element,
+
+  /// This names the __type_list_dedup BuiltinTemplateDecl.
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philnik777 wrote:

I think we've decided somewhere that all new builtin functionality should have a `__builtin_` prefix. The main reason was to avoid naming conflicts. While I don't think that's a huge issue here, we should probably be consistent in that regard. So this should probably be `__builtin_type_pack_dedup`.

https://github.com/llvm/llvm-project/pull/106730