I tried something as bellow. In the common module I have:

interface View{
  suspend fun myFunSuspend().
}

// for Android, normal implementation of co routine
// for iOS see below, because I need to call a function in swift that uses callbacks

class iOSViewWrapper(private val iOSImpl: IosView) : View {

  override suspend fun myFunSuspend(){
    return suspendCoroutine {
      iOSImpl.doAsyncJob{ data, error ->
        if(error != null){
          it.resumeWithException(error)
        }else{
          it.resume(data)
        }
      }
    } 
  }
}

interface IosView {
  fun doAsyncJob((data: ByteArray, error: Throwable?)-> Unit)
}

the function

doAsyncJob

implementation is done in Swift and is called many times inside my kotlin code. I have defined a coroutine scope that is using the ios

dispatch_get_main_queue

. I have made sure that

doAsyncJob

is execute AND invoke the closure on the main thread. The code works but crashes always in the swift invocation of the closure. Sometimes after 1 call sometimes after 6 or 10, ... I tried to declare the closure of

doAsyncJob

as a variable and call

.freeze()

on it, but I get

kotlinx.coroutines.CoroutinesInternalError: Fatal exception in coroutines machinery for DispatchedContinuation[MainDispatcher@7d793018, Continuation @ $prepareCOROUTINE$11]. Please read KDoc to 'handleFatalException' method and report this incident to maintainers
        at 0   mylib                            0x0000000100f81e98 kfun:kotlin.Error.<init>(kotlin.String?;kotlin.Throwable?)kotlin.Error + 24
        at 1   mylib                            0x0000000100f81bc0 kfun:kotlinx.coroutines.CoroutinesInternalError.<init>(kotlin.String;kotlin.Throwable)kotlinx.coroutines.CoroutinesInternalError + 24
        at 2   mylib                            0x0000000100f81818 kfun:kotlinx.coroutines.DispatchedTask.handleFatalException$kotlinx-coroutines-core(kotlin.Throwable?;kotlin.Throwable?) + 284
        at 3   mylib                            0x0000000100f82540 kfun:kotlinx.coroutines.DispatchedTask.run() + 1224

what am I doing wrong? I am using kotlin

1.3.41

and coroutine

1.3.0-RC

with an mpp project android and ios

Are Objective-C Nullability symbols (https://developer.apple.com/swift/blog/?id=25) recognized by cinterop?

Hi, In Kotlin/Native is there a pattern that could be used to get notified about the object that is being collected through Reference Counting? here’s my use case: Let’s say you have a Kotlin class that calls (using C-interop) some dynamic library which perform dynamic allocation on the heap, the pointer of this allocation is stored in the Kotlin class as a

Long

so it can be passed later to make some invocations via the C-interop (the

Long

value is

reinterpret_cast<CppObj*>(pointer)

to whatever the original C/C++ object is), usually we want to deallocate explicitly this pointer when the object get GC’ed via the reference counter. I’m aware of the existing memory management approaches (memScope/arena etc.) but in this scenario we can not wrap every instance of the Kotlin class inside a memScope/arena, these are instances passed to the user of the API so we don’t control their lifecycles, this is why deallocating the C++ resources should be tied to the collection of the original Kotlin instance (to draw a parallel, this is the pattern used in Java with Phantom reference & a referenceQueue to close native pointers, see CrazyBob presentation

The kotlin native tutorial about dynamic libraries (https://kotlinlang.org/docs/tutorials/native/dynamic-libraries.html) has an example about the C++ code creating a Kotlin object instance and releasing it later:

libnative_kref_example_Clazz newInstance = lib->kotlin.root.example.Clazz.Clazz();
  long x = lib->kotlin.root.example.Clazz.memberFunction(newInstance, 42);
  lib->DisposeStablePointer(newInstance.pinned);

What happens if instead I have the following Kotlin code:

interface Foo {}

private class FooImpl : Foo {}

createFoo() : Foo { return FooImpl() }

and I call

createFoo

from C++ (in other words, the object is created on the Kotlin side not the C++ side). How do I tell the Kotlin side that I am going to keep the

Foo

instance for a while? Does it work the same and I am supposed to call

DisposeStablePointer

when I am done?

When accessing ktor from worker thread gives error: Trying to access top level value not marked as @ThreadLocal or @SharedImmutable from non-main thread. All variables are initialized inside of the job and the string constant "OK" is returned

Hi everybody, I'm trying to do K/N hands on, using libcurl. However on Windows, libcurl is not a system lib. I've downloaded binaries but I'm not sure where to drop them inside the project and whether additional buildscript changes are needed to reference it.

I have an issue compiling some code that compiles for the jvm and android targets but fails to compile for iOS. From what I can tell it may be serialization related but I'm not 100% positive. I'm using versions kotlin_version = 1.3.41 & kotlin_serialization_version = 0.11.1

Is it possible to run/debug unit test with kotlin native inside IntelliJ?

Hey guys, I am beginning to study kotlin native, does someone knows, or has an article to explain me the advantages and disvantages of it, comparing it with the quarkus project?

Hi, how can i make all existing build tasks depends on a custom one ? thannnks

I have this problem when using coroutines, ktor and sqldelight in Kotlin Multiplatform on iOS

/Users/teamcity/buildAgent/work/4d622a065c544371/runtime/src/main/cpp/Memory.cpp:770: runtime assert: Must be positive

. I am currently looking at https://github.com/JetBrains/kotlin-native/blob/v1.3.1/runtime/src/main/cpp/Memory.cpp#L770 for clues. Anyone has any ideas how to go about this?

Hi, i’m using kotlin-multiplatform plugin to create ios framework and android aar library. Since i use interop with c-libraries in my project i need to do some special stuff at the end of using my objects: call function, that will free memory, allocated by c-functions. To be sure that memory is always freed (eg if an exception is thrown) i added my own

Closeable

interface and copied

use

extension from

<http://kotlin.io|kotlin.io>

package. It looks like:

interface Closeable {

    fun close()
}

@Throws(Throwable::class)
inline fun <T : Closeable?, R> T.use(block: (T) -> R): R {
    var exception: Throwable? = null
    try {
        return block(this)
    } catch (e: Throwable) {
        exception = e
        throw e
    } finally {
        when {
            this == null -> {}
            exception == null -> close()
            else ->
                try {
                    close()
                } catch (closeException: Throwable) {
                    // cause.addSuppressed(closeException) // ignored here
                }
        }
    }
}

It works fine for android, but in Swift i have some problem. Function signature from xCode:

UtilitiesKt.use(receiver: Closeable?, block: (Closeable?) -> Any?, result: AutoreleasingUnsafeMutablePointer<AnyObject??)

use

function in xCode marked as

trowable

, due to

@Throws(Throwable::class)

annotation, but if i try use

trowable

functions in

block

lambda, xCode says:

Invalid conversion from throwing function of type '(Closeable?) throws -> Any?' to non-throwing function type '(Closeable?) -> Any?'

Maybe someone know, how can i mark lambda parameter as

throwable

in kotlin?

Do i have to do anything special to be able to use the

@Throws

annotation in a

commonMain

module? The IDE doesn't find and i'm using kotlin 1.3.41

What is the URL to use for downloading a tar.gz version of Kotlin Native 1.3.41? Need the file to compile a Kotlin Native program inside a Docker image.

I've needed to get this out of my system for a while now. I just published "Why the Kotlin/Native memory model cannot hold". https://link.medium.com/3qoLYItchZ

I’m sure I knew this but now forget. How does one get around the 32bit/64bit interop situation where NSInteger is an Int in 32 and a Long in 64?

Type mismatch: inferred type is Long but NSInteger /* = Int */ was expected

does anyone here have some experience playing native on embedded devices?

This message was deleted.

are there any variables that I can use within a .DEF file?

question folks: if I need to define a KN function that will be called on Objective-C that returns a string and it has this signature

override fun foo(): CPointer<ByteVar>?

, should I use

StableRef

like:

override fun foo(): CPointer<ByteVar>? {
        return StableRef
            .create(name.encodeToByteArray())
            .asCPointer()
            .rawValue
            .let { interpretCPointer(it) }
    }

This release brings more pre-imported Apple frameworks for all platforms, including macOS and iOS.

Is there any list of this additional frameworks? Or they all listed here: https://github.com/JetBrains/kotlin-native/tree/master/platformLibs/src/platform/ios?

another question: external C library defines a protocol that KN class implements

class MyFooModule : NSObject(), FooModuleProtocol {

. But this information is erased

@interface MyFooModule : KotlinBase

in the result generated header file. How to make header file to look like this

@interface MyFooModule : KotlinBase <FooModule>

?

Oooh K/N compiler performance boost in new release! Has anyone tried it yet?

And

enableFeaturePreview("GRADLE_METADATA")

on consumer side can be removed with 1.3.50 and Gradle 5.6

Now that K/N produces Apple compatible bitcode in frameworks, what would the effort be like to support tvOS? It’s a similar but different SDK from iOS.

After upgrading to 1.3.50 running the build on my ~30 lines of code of kotlin native fails with the following error:

error: Invalid value (Producer: 'LLVM6.0.1' Reader: 'LLVM APPLE_1_900.0.39.2_0')
1 error generated.
e: Compilation failed: The /Applications/Xcode9.2.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ command returned non-zero exit code: 1.
output: 

 * Source files: SampleMacos.kt, PlatformView.kt
 * Compiler version info: Konan: 1.3.50 / Kotlin: 1.3.50
 * Output kind: STATIC

e: org.jetbrains.kotlin.konan.KonanExternalToolFailure: The /Applications/Xcode9.2.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ command returned non-zero exit code: 1.
> Process 'command '/local/sdkman/candidates/java/8.0.212-zulu/bin/java'' finished with non-zero exit value 2

Just an FYI if you plan to migrate...

Hello, I just want to use Kotlin Native to access OpenCV library But, cinterops only process c header but not c++ header Unfortunately OpenCV only has full access with c++ header, is there any solution can I access c++ header with cinterops to generate klib?

After updating Kotlin from 1.3.10 to 1.3.50 for a Kotlin Native project, and running the project as a program a strange error appears:

type Nothing? is not supported here: doesn't correspond to any C type

Double checked the mapping (in the knm file) and found that the return type is

CPointer<gtk3.GtkWidget>?

for the function (

gtk_file_chooser_dialog_new

) that is called in the program. However the function definition looks very odd:

@kotlinx.cinterop.internal.CCall public external fun gtk_file_chooser_dialog_new(@kotlinx.cinterop.internal.CCall.CString title: kotlin.String?, parent: kotlinx.cinterop.CValuesRef<gtk3.GtkWindow /* = gtk3._GtkWindow */>?, action: gtk3.GtkFileChooserAction, @kotlinx.cinterop.internal.CCall.CString first_button_text: kotlin.String?, vararg variadicArguments: kotlin.Any?): kotlinx.cinterop.CPointer<gtk3.GtkWidget /* = gtk3._GtkWidget */>? { /* compiled code */ }

Been looking through some of the mappings generated for the libudev library:

public fun udev_list_entry_get_by_name(list_entry: kotlinx.cinterop.CValuesRef<cnames.structs.udev_list_entry>?, @kotlinx.cinterop.internal.CCall.CString name: kotlin.String?): kotlinx.cinterop.CPointer<cnames.structs.udev_list_entry>? { /* compiled code */ }

public fun udev_list_entry_get_name(list_entry: kotlinx.cinterop.CValuesRef<cnames.structs.udev_list_entry>?): kotlinx.cinterop.CPointer<kotlinx.cinterop.ByteVar /* = kotlinx.cinterop.ByteVarOf<kotlin.Byte> */>? { /* compiled code */ }

public fun udev_list_entry_get_next(list_entry: kotlinx.cinterop.CValuesRef<cnames.structs.udev_list_entry>?): kotlinx.cinterop.CPointer<cnames.structs.udev_list_entry>? { /* compiled code */ }

public fun udev_list_entry_get_value(list_entry: kotlinx.cinterop.CValuesRef<cnames.structs.udev_list_entry>?): kotlinx.cinterop.CPointer<kotlinx.cinterop.ByteVar /* = kotlinx.cinterop.ByteVarOf<kotlin.Byte> */>? { /* compiled code */ }

There doesn't appear to be a definition in any of the knm files for

udev_list_entry

(a C struct), however

cnames.structs.udev_list_entry

does exist but its definition doesn't seem to appear in any of the knm files which is strange.