With Kotlin 2.1.0-RC, I’m seeing some weird issues...

# eap

[Carter]

With Kotlin 2.1.0-RC, I’m seeing some weird issues with native builds, coroutines, and the new annotations for SubclassOptInRequired which are failing my build.

[Carter]

> Task :common-blob-file-lib:linkDebugTestMacosArm64
i: <org.jetbrains.kotlinx:kotlinx-coroutines-core> @ /opt/buildAgent/work/44ec6e850d5c63f0/kotlinx-coroutines-core/common/src/CancellableContinuation.kt:1:1: Constructor 'SubclassOptInRequired.<init>' can not be called: No constructor found for symbol 'kotlin/SubclassOptInRequired.<init>|<init>(kotlin.reflect.KClass<out|kotlin.Annotation>){}[0]'
i: <org.jetbrains.kotlinx:kotlinx-coroutines-core> @ /opt/buildAgent/work/44ec6e850d5c63f0/kotlinx-coroutines-core/common/src/CancellableContinuation.kt:44:1: Unusable annotation 'SubclassOptInRequired.<init>' has been removed from interface 'CancellableContinuation'
i: <missing declarations>: No constructor found for symbol 'kotlin/SubclassOptInRequired.<init>|<init>(kotlin.reflect.KClass<out|kotlin.Annotation>){}[0]'

[tapchicoma]

please create a new Kotlin issue with repro

[Carter]

https://youtrack.jetbrains.com/issue/KT-72900/SubclassOptInRequired-failure-with-coroutines-and-Kotlin-native

[Carter]

Reproducer attached as comment with jetbrains team visiblity. It shouldn’t have anything sensitive, but just in case since it was a distillation from a much larger project.

[tapchicoma]

cc @svyatoslav.scherbina

[Pavel Kunyavskiy [JB]]

This is duplicate of https://youtrack.jetbrains.com/issue/KT-72471/2.1.0-Beta2-Removal-of-SubclassOptInRequired-results-in-many-warnings-from-coroutines

[Carter]

Is it just noise?

I’m seeing my tests actually hang.

[Carter]

That’s OK if we have to wait for a new Coroutines release post Kotlin 2.1, but for now this seems to block testing Kotlin 2.1.0-RC with my native targets.

[Pavel Kunyavskiy [JB]]

If it's only about SubclassOptInRequired it's just an unfortunate noise.

[Pavel Kunyavskiy [JB]]

I see, the hang looks unrelated problem, maybe it's already known and planned to be fixed in RC2, I'll check

[Pavel Kunyavskiy [JB]]

Are you sure this supposed to work? For me it doesn't work on either
• K/N 2.0
• K/N 2.0.20
• K/JVM 2.1.0

[Carter]

I think that was a mistake when I was trying to distill down from a larger project.

[Carter]

I am able to get this to run now.

I was running into multiple other Kotlin 2.1-RC issues simultaneously, which caused some confusion.

[Carter]

Thanks for you help looking at this.

[Pavel Kunyavskiy [JB]]

So, is there any problem except noisy messages?

[Carter]

Correct, false alarm about the tests hanging. I’m pretty sure it was something unrelated.