[clang] [clang] Fix C++20 list initialization of const references to arrays of unknown bound (PR #218225)

[Corentin Jabot via cfe-commits]

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@@ -48,3 +48,21 @@ void gh151716_f() {
 }
 
 } // namespace One
+
+namespace Two {
+
+void unknownBoundArrayRef(const int (&)[]);
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cor3ntin wrote:

Do we have sema tests with rvalue ref and non-const ref (the latter should fail)

https://github.com/llvm/llvm-project/pull/218225