[clang] [clang][PAC] Fix builtins that claim address discriminated types are bitwise compatible (PR #154490)

[Oliver Hunt via cfe-commits]

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@@ -1438,6 +1438,10 @@ void CXXRecordDecl::addedMember(Decl *D) {
         data().StructuralIfLiteral = false;
     }
 
+    if (!data().HasTrivialSpecialMembers &&
+        T.hasAddressDiscriminatedPointerAuth())
+      data().HasTrivialSpecialMembers = true;
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ojhunt wrote:

yes, so the question is why did nothing seem to break (as in what test would this break - it's possible that it gets masked by other pointer auth state)

https://github.com/llvm/llvm-project/pull/154490