[clang] [Clang] Diagnose forming references to nullptr (PR #143667)

[Eli Friedman via cfe-commits]

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@@ -4503,7 +4505,7 @@ static CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E,
   } else {
     const Expr *Base = LVal.Base.dyn_cast<const Expr*>();
 
-    if (!Frame) {
+    if (!Frame && AK != clang::AK_CheckReferenceInitialization) {
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efriedma-quic wrote:

This check looks a little weird... what's it doing?

https://github.com/llvm/llvm-project/pull/143667