Dmitriy Dolovov
7382b31fdc
Kotlin/Native codegen needs to deserialize all fields throughout the class hierarchy to build the proper binary class layout. That becomes impossible with the guard condition that prevents loading private top-level classes from another module in LazyIR (see https://github.com/JetBrains/kotlin/blob/2a4d8800374578c1aa9ec9c996b393a98f5a6e3b/kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/KonanIrlinker.kt#L701). The guard suits well for the partial linkage needs, but it causes the codegen to fail with `Unbound public symbol IrClassPublicSymbolImpl: [ File '/file/in/the/library.kt' <- private.top.level/ClassDeclaration|null[0] ]` error. To prevent this the guard is removed. This does not influence the partial linkage in general except for the different error message being generated: `Function 'foo' can not be called: Private function declared in module <A> can not be accessed in module <B>` instead of `Function 'foo' can not be called: No function found for symbol '<symbol>'`. #KT-54469
Kotlin/Native
Kotlin/Native is an LLVM backend for the Kotlin compiler, runtime implementation, and native code generation facility using the LLVM toolchain.
Kotlin/Native is primarily designed to allow compilation for platforms where virtual machines are not desirable or possible (such as iOS or embedded targets), or where a developer is willing to produce a reasonably-sized self-contained program without the need to ship an additional execution runtime.
Using published Kotlin/Native versions
The most complete experience with Kotlin/Native can be achieved by using Gradle, IntelliJ IDEA or Android Studio with KMM plugin if you target iOS.
If you are interested in using Kotlin/Native for iOS, then Kotlin Multiplatform Mobile portal might be useful for you.
Command line compiler is also available.
More information can be found in the overviews of Kotlin/Native and Kotlin Multiplatform.
On macOS Kotlin/Native requires Xcode 12.5 or newer.
Contributing
You can contribute to Kotlin/Native in many ways. See the relevant page on the website.
See also the general contribution guidelines for this repository.
Building from source
Prerequisites:
- configure Kotlin build as specified in main readme
- at the root directory of the repository,
create
local.propertiesfile withkotlin.native.enabled=trueline - macOS: Xcode 14.0 or newer
-
on
MacOS aarch64, CInterop functionality is available only using aarch64 JDK builds, e.g. Eclipse Temurin 17.0.5 or Azul Zulu JDK8Note: using
JDK x86_64onMacOS aarch64will causejava.lang.UnsatisfiedLinkErrorforlibclang.dylib
-
- Linux: glibc 2.23 or newer
- Windows:
- Microsoft C++ build tools for Visual Studio 2019 14.29 or newer
- Windows SDK 10.0.18362.0 or newer
The commands below should be run from either repository root or this (kotlin-native/) directory.
For the latter, :kotlin-native: task name prefix can be omitted.
To compile the basic compiler distribution from sources, run following command:
./gradlew :kotlin-native:dist
It will build compiler and stdlib for host target, without platform libraries.
To get platform libraries, add distPlatformLibs task, e.g.
./gradlew :kotlin-native:dist :kotlin-native:distPlatformLibs
To run the full build:
./gradlew :kotlin-native:bundle
This will produce compiler and libraries for all supported targets. The full build can take about an hour on a Macbook Pro.
After any of the commands above, ./dist will contain Kotlin/Native distribution.
You can use it like a distribution of
command-line compiler.
Or configure Gradle to use it -- just add the following line to
gradle.properties in your Gradle project:
kotlin.native.home=/path/to/kotlin/kotlin-native/dist
To compile your programs with command-line compiler, use:
./dist/bin/kotlinc-native hello.kt -o hello
For an optimized compilation, use -opt:
./dist/bin/kotlinc-native hello.kt -o hello -opt
Interoperability
To import a C or Objective-C library, use ./dist/bin/cinterop tool.
See the documentation for more details.
Note: on MacOS aarch64, JDK aarch64 is required
Running tests
For tests, use ./gradlew :native:native.tests:codegenBoxTest and ./gradlew :kotlin-native:backend.native:tests:run.
Note: on MacOS aarch64, for target-specific tests, JDK aarch64 is required
For more details see Testing.
More tips and tricks
More tips and tricks that might be useful when developing or debugging Kotlin/Native can be found in HACKING.md