[clang] [Clang][P1061] Consolidate ResolvedUnpexandedPackExpr into FunctionParmPackExpr (PR #125394)

[Jason Rice via cfe-commits]

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@@ -3492,10 +3492,13 @@ VarDecl *BindingDecl::getHoldingVar() const {
   return VD;
 }
 
-llvm::ArrayRef<Expr *> BindingDecl::getBindingPackExprs() const {
+llvm::ArrayRef<BindingDecl *> BindingDecl::getBindingPackDecls() const {
   assert(Binding && "expecting a pack expr");
-  auto *RP = cast<ResolvedUnexpandedPackExpr>(Binding);
-  return RP->getExprs();
+  auto *FP = cast<FunctionParmPackExpr>(Binding);
+  ValueDecl *const *First = FP->getNumExpansions() > 0 ? FP->begin() : nullptr;
+  assert((!First || isa<BindingDecl>(*First)) && "expecting a BindingDecl");
+  return llvm::ArrayRef<BindingDecl *>(
+      reinterpret_cast<BindingDecl *const *>(First), FP->getNumExpansions());
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ricejasonf wrote:

`llvm::cast` will not return a reference to the pointer so it cannot be used for the ArrayRef.

https://github.com/llvm/llvm-project/pull/125394