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

[Jason Rice via cfe-commits]

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@@ -12726,11 +12726,15 @@ bool ASTContext::DeclMustBeEmitted(const Decl *D) {
 
   // Likewise, variables with tuple-like bindings are required if their
   // bindings have side-effects.
-  if (const auto *DD = dyn_cast<DecompositionDecl>(VD))
-    for (const auto *BD : DD->bindings())
-      if (const auto *BindingVD = BD->getHoldingVar())
-        if (DeclMustBeEmitted(BindingVD))
-          return true;
+  if (const auto *DD = dyn_cast<DecompositionDecl>(VD)) {
+    bool BindingResult = false;
+    DD->VisitHoldingVars([&](VarDecl *BindingVD) {
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ricejasonf wrote:

I replaced the Visit functions with `flat_bindings` and reverted the places where I was using them. I will look to see if there is some existing iterator that you are referring to if it would be simple than `flat_binding_iterator` (which had some things I had to fix.)

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