[clang] [clang] Add tests for CWG issues regarding completeness of types (PR #92113)

[Vlad Serebrennikov via cfe-commits]

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@@ -67,6 +63,27 @@ void B<int>::g() requires true;
 
 } // namespace cwg2847
 
+namespace cwg2857 { // cwg2857: 2.7
+struct A {};
+struct B {
+  int operator+(A);
+};
+template <typename>
+struct D;
+
+void f(A* a, D<int>* d) {
+  *d + *a;
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Endilll wrote:

Thank you! I used one of your tests instead, and stopped claiming that CWG2857 is available.

https://github.com/llvm/llvm-project/pull/92113