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

[Aaron Ballman 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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AaronBallman wrote:

It would crash anyway if we fell through because the first thing done in `Type::Record` is a `getAs<RecordType>()` followed by `->` which will dereference a null pointer when handed a `BuiltinType`.

I believe the intent here is that all the cases in the nested `switch` are expected to return and that we handle all of the builtin types.

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