[clang] [clang] Warn about deprecated volatile-qualified return types (PR #137899)

[Mariya Podchishchaeva via cfe-commits]

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@@ -231,6 +231,13 @@ namespace DeprecatedVolatile {
     a = c = a;
     b += a;
   }
+
+  volatile struct amber jurassic();
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Fznamznon wrote:

Yeah, these are what I meant. Thanks!

https://github.com/llvm/llvm-project/pull/137899