I have an issue with using coroutines on kotlin na...

# kotlin-native

[Tim Ortel]

I have an issue with using coroutines on kotlin native. I need to suspend my coroutine until a call to an api is done. However, the call to the api internally executes the code on another thread. Therefore, the following error is thrown:
Uncaught Kotlin exception: kotlin.native.concurrent.InvalidMutabilityException: mutation attempt of frozen kotlinx.coroutines.internal.DispatchedContinuation

runBlocking {
    withContext(Dispatchers.Main) {
        suspendCoroutine { c ->
            //handler is called from another thread.
            val handler = { x -> c.resume(x) }

            //Internally, schedules the work on another thread.
            //Therefore, c.resume() fails, as c is frozen.
            some_api_that_schedules_another_thread(handler)
        }
    }
}

Is there any way around of this. Changing the internal API is not possible.

[John O'Reilly]

Not a direct answer but are you able to try the new Kotlin Native memory model?

[John O'Reilly]

It's use should spell the end of those InvalidMutabilityException errors.

[John O'Reilly]

You can enable by adding following to your gradle.properties

kotlin.native.binary.memoryModel=experimental

[John O'Reilly]

depending on libraries you're using you might also want to add

kotlin.native.binary.freezing=disabled

[John O'Reilly]

And I believe you need to be on Kotlin 1.6.20 or later

[Trevor Stone]

You could, as a work around, use something like a mutable state flow, pass that to the handler, emit to it on the other thread and collect on the initial thread. Once it emits you call c cancel without passing it around