hey folks, first time trying Kotlin Native. Is Xcode mandatory for Kotlin Native ? I am trying to build the demo project https://github.com/kotlin-hands-on/intro-kotlin-native but I am getting

23:30:05: Executing tasks ':assemble :macosMainBinaries :macosTestBinaries --stacktrace'...


> Configure project :
Kotlin Multiplatform Projects are an experimental feature.

> Task :cinteropLibcurlMacos FAILED
xcrun: error: unable to find utility "xcodebuild", not a developer tool or in PATH
Exception in thread "main" org.jetbrains.kotlin.konan.MissingXcodeException: An error occurred during an xcrun execution. Make sure that Xcode and its command line tools are properly installed.
	at org.jetbrains.kotlin.konan.target.CurrentXcode.xcrun(Xcode.kt:77)
	at org.jetbrains.kotlin.konan.target.CurrentXcode.access$xcrun(Xcode.kt:45)
	at org.jetbrains.kotlin.konan.target.CurrentXcode$version$2.invoke(Xcode.kt:70)
	at org.jetbrains.kotlin.konan.target.CurrentXcode$version$2.invoke(Xcode.kt:45)
	at kotlin.SynchronizedLazyImpl.getValue(LazyJVM.kt:74)
	at org.jetbrains.kotlin.konan.target.CurrentXcode.getVersion(Xcode.kt)
	at org.jetbrains.kotlin.konan.target.AppleConfigurablesImpl$xcodePartsProvider$2.invoke(Apple.kt:71)
	at org.jetbrains.kotlin.konan.target.AppleConfigurablesImpl$xcodePartsProvider$2.invoke(Apple.kt:24)
	at kotlin.SynchronizedLazyImpl.getValue(LazyJVM.kt:74)
	at org.jetbrains.kotlin.konan.target.AppleConfigurablesImpl.getXcodePartsProvider(Apple.kt)
	at org.jetbrains.kotlin.konan.target.AppleConfigurablesImpl.getAbsoluteTargetToolchain(Apple.kt:48)
	at org.jetbrains.kotlin.konan.target.ClangArgs.getAbsoluteTargetToolchain(ClangArgs.kt)
	at org.jetbrains.kotlin.konan.target.ClangArgs.<init>(ClangArgs.kt:351)
	at org.jetbrains.kotlin.konan.target.Platform$clang$2.invoke(Platform.kt:25)
	at org.jetbrains.kotlin.konan.target.Platform$clang$2.invoke(Platform.kt:21)
	at kotlin.SynchronizedLazyImpl.getValue(LazyJVM.kt:74)
	at org.jetbrains.kotlin.konan.target.Platform.getClang(Platform.kt)
	at org.jetbrains.kotlin.native.interop.tool.ToolConfig.<init>(ToolConfig.kt:37)
	at org.jetbrains.kotlin.native.interop.gen.jvm.MainKt.prepareTool(main.kt:377)
	at org.jetbrains.kotlin.native.interop.gen.jvm.MainKt.processCLib(main.kt:181)
	at org.jetbrains.kotlin.native.interop.gen.jvm.MainKt.interop(main.kt:46)
	at org.jetbrains.kotlin.cli.utilities.InteropCompilerKt.invokeInterop(InteropCompiler.kt:44)
	at org.jetbrains.kotlin.cli.utilities.MainKt.mainImpl(main.kt:19)
	at org.jetbrains.kotlin.cli.utilities.MainKt.main(main.kt:37)
Caused by: org.jetbrains.kotlin.konan.KonanExternalToolFailure: The /usr/bin/xcrun command returned non-zero exit code: 72.
output:

	at org.jetbrains.kotlin.konan.exec.Command.handleExitCode(ExecuteCommand.kt:111)
	at org.jetbrains.kotlin.konan.exec.Command.getResult(ExecuteCommand.kt:100)
	at org.jetbrains.kotlin.konan.exec.Command.getOutputLines(ExecuteCommand.kt:79)
	at org.jetbrains.kotlin.konan.exec.Command.getOutputLines$default(ExecuteCommand.kt:78)
	at org.jetbrains.kotlin.konan.target.CurrentXcode.xcrun(Xcode.kt:75)
	... 23 more

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':cinteropLibcurlMacos'.
> Process 'command '/Library/Java/JavaVirtualMachines/adoptopenjdk-8.jdk/Contents/Home/bin/java'' finished with non-zero exit value 1

I am confused as i can’t see anywhere in the docs Xcode as prerequisite.

Can we expect K/N compiler to update LLVM anytime soon?

Hey guys. Why kotlin native supports only single-threaded code for coroutines? Is it temporary?

Any thoughts on why this would happen only in K/N? https://youtrack.jetbrains.com/issue/KT-38540

We have an issue with a Kotlin Native (KN) project when running a class from a JVM module results in a NoClassDefFoundError on a class from the common module. If we run this class using Gradle, the code runs without problems. I have re-created the issue in a sample project we use to test new things and can be found here: https://github.com/jcraane/KotlinNativeStarter The project structure is as follows:

root
    android
        app (Android application)
    common (multiplatform module (common code, iOS, Android and JVM)
    buildSrc (some custom Gradle tasks)
    iosApp (The iOS application)
    jvmmodule (The JVM module, this is were it is all about)
    localization (some custom localization code for Android and iOS)

The project is utilizing Kotlin 1.3.72 and Gradle 6.3. When checking out and importing the project into the IDE (Android Studio or IntelliJ) the problem is replicated by doing the following: Scenario 1 (running from the IDE) Actual: - Open the MyMainClass and click the Play icon in the gutter to execute the main method - The run window of the IDE outputs “Exception in thread “main” java.lang.NoClassDefFoundError: nl/jamiecraane/nativestarter/api/MockApi” Expected: - The main method is excuted and the response from the MockApi is displayed in the console Scenario 2 (running from Gradle) For this, we configured the Gradle application plugin to execute the MyMainClassKt. Run the following command from the command line: ./gradlew :jvmmodule:run The result of this execution is the following (as expected, without a NoClassDefFoundError)

> Task :jvmmodule:run
Hello
Response data: [Person(firstName=Jan, lastName=Janssen), Person(firstName=John, lastName=Smith)]

What can be the reason for this issue (NoClassDefFoundError when running the MyMainClass from the IDE instead of Gradle)?

Why does the K/N target for Mac and iOS require the full Xcode suite, rather than just the command line tools? It’s a massive difference in size and I was hoping I could avoid installing the entire IDE.

hi I have the following struct from kafka c lib

typedef struct rd_kafka_message_s {
      ...
	void   *payload;           /**< Producer: original message payload.
				    * Consumer: Depends on the value of \c err :
				    * - \c err==0: Message payload.
				    * - \c err!=0: Error string */
	size_t  len;               /**< Depends on the value of \c err :
				    * - \c err==0: Message payload length
				    * - \c err!=0: Error string length */
	...
} rd_kafka_message_t;

I am struggling to figure out how to read the payload to a bytearray from Kotlin the interop binding gives me

public final var payload: kotlinx.cinterop.COpaquePointer? /* = kotlinx.cinterop.CPointer<out kotlinx.cinterop.CPointed>? */

public final var len: platform.posix.size_t /* = kotlin.ULong */

I’m having some trouble when adding methods and classes to a Swift library I’m calling from K/N. The new classes and methods won’t show up but the old ones work. Is there any way to force refresh the cinterop bindings or similar? (I build a new .framework and replace the old one and new Swift methods and classes are not accessible from K/N)

This is more of a build question I guess. I'm trying to build a native target that uses ncurses. I've created a def file and tweaked binary target. I can see in the build that ncurses.kt file was created. What do I have to change in the build to start using ncurses in the commonMain source code?

I’m having trouble getting cinterop working on Linux. eg here’s a minimal repo trying to include sdbm directly from source. On macosX64 it builds fine, but on linuxX64 I get undefined symbol errors on linking. What am I missing?

Hi, how can I check the current thread is main thread in Linux?

I have anther problem. Is there any way to implement a mechanism on native like Handler.post(runnable) on android? when I accomplish the backend job in Worker, I want switch to calling thread (Main thread), Could anyone help me?

Hey folks question about https://kotlinlang.org/docs/reference/native/objc_interop.html#generics I know there are limitations but is list parameterized with nullable type is one of such limitation, I mean

List<SomeType?>

is translated to objectiveC / Swift as

[Any]

. @kpgalligan as far as I remember you were working on adding generics support, could you please advise?

How would I specify in my gradle file that the code should be applicable to both the 64 bit and the 32 bit version of windows?

When I execute the task compileKotlinMacosX64，I get the errors below: • Unresolved reference: __syscall_slong_t • Unresolved reference: __time_t • Unresolved reference: pthread_condattr_setclock • Unresolved reference: pthread_condattr_setclock • Unresolved reference: __time_t • Unresolved reference: __syscall_slong_t • Unresolved reference: __syscall_slong_t  the errors occured in naitveMain module, I use some posix APIs in my code, and I config both macosX64Main and linuxX64Main dependsOn nativeMain Am I doing something wrong?

When I’m trying to build this sample from Xcode https://github.com/JetBrains/kotlin-native/tree/master/samples/cocoapods I’m getting an error. Do you have an idea what am i do wrong?

Does anyone know a good way how to do a timeout in a worker? How do I cancel the worker job without cancelling the worker itself?

Does anyone know how I can convert a

CFStringRefVar

to a Kotlin

String

?

Hi everyone, I get different results using

cos

function in K/N, i.e:

@Test
fun cosine_functions_works_the_same_in_all_platform() {
    assertEquals(0.6441559905471732, cos(0.8708769899641021))
}

This test pass in JVM and JS, but fails in iOS:

kotlin.AssertionError: Expected <0.6441559905471732>, actual <0.6441559905471733>.

How does C library dependency resolution work in Kotlin Native?

Hi, when I compile the task linkDebugSharedLinuxX64, I get the error below:

Produced library API in libkn_xxx_api.h

e: /home/jeff/.konan/dependencies/clang-llvm-8.0.0-linux-x86-64/bin/ld.lld invocation reported errors

The /home/jeff/.konan/dependencies/clang-llvm-8.0.0-linux-x86-64/bin/ld.lld command returned non-zero exit code: 1.

output:

ld.lld: error: unable to find library -lcurl

Task :effectmanager:linkDebugSharedLinuxX64 FAILED

FAILURE: Build failed with an exception.

Anyone who knows how to solve it?

Hi folks! I wonder if someone in this chat uses Kotlin/Native arm32/arm64 target to compile code for Android. If yes - could you please share your case with me in direct messages - or here in the thread? Thanks!

Hey Guys. I was using Kotlin 1.3.61, with coroutines 1.3.2-native-mt-1 and serialization 0.14.0 I just updated to Kotlin 1.3.71, coroutines 1.3.5-native-mt and serialization 0.20.0 and getting this error when I build for iOS framework Please help

e: Cannot access class 'kotlin.Pair'. Check your module classpath for missing or conflicting dependencies
e: Cannot access class 'kotlinx.coroutines.CoroutineExceptionHandler'. Check your module classpath for missing or conflicting dependencies
e: Cannot access class 'kotlin.collections.HashMap'. Check your module classpath for missing or conflicting dependencies

Hi folks, I'm writing some tests and I need a way to post operations to the main queue and make the test case wait for the queue to be empty before finishing (What I tried to do the the 

sleep

 without success)

@Test
fun `This test doesn't execute the println statement`() {
    dispatch_async(dispatch_get_main_queue()) {
        println("dispatch_async")
    }

    NSThread.sleepForTimeInterval(1.0)
}

I'm thinking about something similar to

XCTestExpectation

. Any thoughts?

Hey I am facing an error while building my project with new kotlin version 1.3.71 and the associated libs.

e: Cannot access class 'kotlinx.coroutines.CoroutineExceptionHandler'. Check your module classpath for missing or conflicting dependencies

I have created a small reproducible project with two branches. master that does not build and gives an error and working-old-version that builds successful. The only difference between the two branches is the versions of libs. https://github.com/kerry/kn-multilib To run the build

SDK_NAME=iphoneos-hello ./gradlew :analytics:build

Can someone help?

Hypothetically speaking If the Kotlin Native team were doing third party Kotlin Native wrappers for the GObject libraries (GTK, Pango, Cairo etc) how would they do it (including handling complex C library dependencies)? GTK is well known for having complex C library dependencies, which are so complex that it isn't possible to statically link GTK itself.

Is Kotlin native copy hard coded or reference is passed ? when

val s1 = "hello"
var s2 = s1

And can anyone explain data race conditions in Kotlin ? Is there brief explanation what's going on under the hood

Does it use the DCE/garbage collection pass in

ld

? that's a common trick for deleting unused code. It basically removes symbols that have no references from other symbols