[clang] [clang][NFC] Add CWG882 test (Defining `main` as deleted) (PR #101382)

[Vlad Serebrennikov via cfe-commits]

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@@ -30,3 +30,8 @@ void g(int i) {
 }
 #endif
 } // namespace cwg873
+
+// cwg882: 3.5
+int main() = delete;
+// expected-error at -1 {{'main' is not allowed to be deleted}}
+// cxx98-error at -2 {{deleted function definitions are a C++11 extension}}
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Endilll wrote:

`delete` came in C++11, so you should guard the test with `#ifdef __cplusplus`

https://github.com/llvm/llvm-project/pull/101382