[clang] [ASTContext] Add a break to nested switch in `encodeTypeForFunctionPointerAuth` (PR #99763)

[Brandon Wu via cfe-commits]

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@@ -3363,6 +3363,7 @@ static void encodeTypeForFunctionPointerAuth(const ASTContext &Ctx,
 #include "clang/Basic/RISCVVTypes.def"
       llvm_unreachable("not yet implemented");
     }
+    break;
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4vtomat wrote:

Would it break if the case is not presented if we change to `llvm_unreachable()`?

https://github.com/llvm/llvm-project/pull/99763