[clang] [Clang] Deleting an incomplete enum type is not an error (PR #118455)

[Erich Keane via cfe-commits]

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@@ -540,6 +540,14 @@ namespace PR10504 {
   void f(A *x) { delete x; } // expected-warning {{delete called on 'PR10504::A' that is abstract but has non-virtual destructor}}
 }
 
+#if __cplusplus >= 201103L
+enum GH99278_1 { // expected-note {{definition of 'GH99278_1' is not complete until the closing '}'}}
+    zero = decltype(delete static_cast<GH99278_1*>(nullptr), 0){}
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erichkeane wrote:

Yeah, if this doesnt' end up being UB, there isn't really value to diagnosing this.  If someone is willing to go through THESE level of machinations, I think we should leave them alone :) 

https://github.com/llvm/llvm-project/pull/118455