[clang] [Clang] [Sema] Fix a crash when a `friend` function is redefined as deleted (PR #135679)

[Mariya Podchishchaeva via cfe-commits]

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@@ -271,3 +271,33 @@ void operators() {
   if (to_int_int) {} // expected-error {{attempt to use a deleted function: deleted (TO<int, int>, operator bool)}}
   static_cast<bool>(to_int_int); // expected-error {{static_cast from 'TO<int, int>' to 'bool' uses deleted function: deleted (TO<int, int>, operator bool)}}
 };
+
+namespace gh135506 {
+struct a {
+  // FIXME: We currently don't diagnose these invalid redeclarations if the
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Fznamznon wrote:

Does it make sense to create a gh issue?

https://github.com/llvm/llvm-project/pull/135679