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kotlinlang

encountered an error with Kotlin 2.0.0-RC2 that was extremely difficult to track down

```// module :a
sealed class AResult<T> { ... }

// module :b, dependencies { implementation(":a") }
sealed class BResult<T> { ... }
suspend fun service() = ... // BResult<AResult<...>>, not written explicitly

// module :c, dependencies { implementation(":b") }
when (service()) {
    is BResult.Success -> ...```
this failed with `IllegalStateException: Can't find KotlinType in IrErrorType: IrErrorType(null)` and a huge stacktrace, nothing mentioning the non-exposed `AResult` type as the problem

obviously this was a problem in our codebase but it took a lot of investigation to find

Thanks for sharing! Did you open an issue on YouTrack?

:plus-one: Yes, it would be great to open an issue