[clang-tools-extra] [clang-tidy] Fix virtual inheritance FP in misc-multiple-inheritance (PR #186103)

[Zeyi Xu via cfe-commits]

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@@ -163,3 +163,22 @@ struct S2 { int i; };
 struct S3 : S1, S2 {};
 
 } // namespace N
+
+namespace M {
+
+class basic_ios { int state; };
+class ostream : virtual public basic_ios { int more_state; };
+class OStringStream final : public ostream {};
+
+struct A { int x; };
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zeyi2 wrote:

These two cases are here to avoid regression :)

I think they are not covered before.

https://github.com/llvm/llvm-project/pull/186103