When updating from Kotlin 2.4.0 to 2.4.20-Beta1 (f...

# compose-desktop

[PHondogo]

When updating from Kotlin 2.4.0 to 2.4.20-Beta1 (for both versions project depends on compose 1.12.0-alpha02) got runtime error

java.lang.ClassNotFoundException: androidx.compose.runtime.internal.ComposableFunction0

What can be the cause? How to fix it?

[Pavel Shishkin]

hi! ive just tried to change compose/kotlin versions on template project from https://kmp.jetbrains.com/, everything works as expected
could you please share larger stacktrace/target (is it broken for all target in your setup?)/reproduction sample?

[PHondogo]

@Pavel Shishkin hello! Extracted repro and created an YT issue: youtrack.jetbrains.com/issue/CMP-10407/CMP-ClassNotFound-for-JVM-unknown-symbol-on-WEB-when-interface-with-default-arg-is-used

[Pavel Shishkin]

looks like it is closely related to another issue reported by you https://youtrack.jetbrains.com/issue/CMP-9392 (which is, to my shame, is still not fixed)
unfortunately, im going to vacation since tomorrow and would not be able to fix it (it would be #1 issue after vacation because we have at least two more issues in that area)

the main problem here is default parameter on interface member + cross-module call to such a function
so to workaround the issue you could try temporarily removing default value (it works for current and previous issues, should help in another cases too)