[clang] [Clang][P1061] Add stuctured binding packs (PR #121417)

[Erich Keane via cfe-commits]

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@@ -2484,6 +2488,14 @@ TemplateInstantiator::TransformDeclRefExpr(DeclRefExpr *E) {
     if (PD->isParameterPack())
       return TransformFunctionParmPackRefExpr(E, PD);
 
+  if (BindingDecl *BD = dyn_cast<BindingDecl>(D); BD && BD->isParameterPack()) {
+    BD = cast<BindingDecl>(TransformDecl(BD->getLocation(), BD));
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erichkeane wrote:

Yep! And this cast will fail here if that is the case. 

https://github.com/llvm/llvm-project/pull/121417