[clang] [clang-tools-extra] [Clang] Add a builtin that deduplicate types into a pack (PR #106730)

[Erich Keane via cfe-commits]

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@@ -4014,8 +4010,8 @@ Decl *TemplateDeclInstantiator::instantiateUnresolvedUsingDecl(
     bool RetainExpansion = false;
     UnsignedOrNone NumExpansions = std::nullopt;
     if (SemaRef.CheckParameterPacksForExpansion(
-          D->getEllipsisLoc(), D->getSourceRange(), Unexpanded, TemplateArgs,
-            Expand, RetainExpansion, NumExpansions))
+            D->getEllipsisLoc(), D->getSourceRange(), Unexpanded, TemplateArgs,
+            true, Expand, RetainExpansion, NumExpansions))
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erichkeane wrote:

here

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