[clang] [Clang] Fix missing diagnostic for non-standard layout type in `offsetof` (PR #65246)

[Aaron Ballman via cfe-commits]

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@@ -17,7 +17,7 @@ struct Base { int x; };
 struct Derived : Base { int y; };
 int o = __builtin_offsetof(Derived, x); // expected-warning{{offset of on non-POD type}}
 
-const int o2 = sizeof(__builtin_offsetof(Derived, x));
+const int o2 = sizeof(__builtin_offsetof(Derived, x)); // expected-warning{{offset of on non-POD type 'Derived'}}
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AaronBallman wrote:

I think that might produce slightly better results by silencing this kind of warning.

https://github.com/llvm/llvm-project/pull/65246