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

[Jason Rice via cfe-commits]

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@@ -1166,26 +1166,54 @@ TemplateDeclInstantiator::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
 
 Decl *TemplateDeclInstantiator::VisitBindingDecl(BindingDecl *D) {
   auto *NewBD = BindingDecl::Create(SemaRef.Context, Owner, D->getLocation(),
-                                    D->getIdentifier());
+                                    D->getIdentifier(), D->getType());
   NewBD->setReferenced(D->isReferenced());
   SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, NewBD);
+
   return NewBD;
 }
 
 Decl *TemplateDeclInstantiator::VisitDecompositionDecl(DecompositionDecl *D) {
   // Transform the bindings first.
+  // The transformed DD will have all of the concrete BindingDecls.
   SmallVector<BindingDecl*, 16> NewBindings;
-  for (auto *OldBD : D->bindings())
+  ResolvedUnexpandedPackExpr *OldResolvedPack = nullptr;
+  for (auto *OldBD : D->bindings()) {
+    Expr *BindingExpr = OldBD->getBinding();
+    if (auto *RP = dyn_cast_if_present<ResolvedUnexpandedPackExpr>(BindingExpr))
+      OldResolvedPack = RP;
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ricejasonf wrote:

The `isa<PackExpansionType>` call would fail on a null type so I just left a comment.

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