[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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@@ -3736,12 +3735,9 @@ TemplateDeclInstantiator::VisitTemplateTemplateParmDecl(
     bool Expand = true;
     bool RetainExpansion = false;
     UnsignedOrNone NumExpansions = std::nullopt;
-    if (SemaRef.CheckParameterPacksForExpansion(D->getLocation(),
-                                                TempParams->getSourceRange(),
-                                                Unexpanded,
-                                                TemplateArgs,
-                                                Expand, RetainExpansion,
-                                                NumExpansions))
+    if (SemaRef.CheckParameterPacksForExpansion(
+            D->getLocation(), TempParams->getSourceRange(), Unexpanded,
+            TemplateArgs, true, Expand, RetainExpansion, NumExpansions))
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erichkeane wrote:

and here

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