[clang] [Clang] Diagnose defaulted assignment operator with incompatible object parameter (PR #70176)

[Aaron Ballman via cfe-commits]

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@@ -7748,6 +7748,24 @@ bool Sema::CheckExplicitlyDefaultedSpecialMember(CXXMethodDecl *MD,
         HadError = true;
       }
     }
+    // [C++23][dcl.fct.def.default]/p2.2
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AaronBallman wrote:

Oh! I was thinking that spaceship was also a special member function that can be defaulted, but you're right, that's... not special. Thank you!

https://github.com/llvm/llvm-project/pull/70176