[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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@@ -133,7 +133,7 @@ static void instantiateDependentAlignedAttr(
   // FIXME: Use the actual location of the ellipsis.
   SourceLocation EllipsisLoc = Aligned->getLocation();
   if (S.CheckParameterPacksForExpansion(EllipsisLoc, Aligned->getRange(),
-                                        Unexpanded, TemplateArgs, Expand,
+                                        Unexpanded, TemplateArgs, true, Expand,
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erichkeane wrote:

Another bool in need of a comment.

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