Contents

The release contents the JVM version of the Kotlin compiler, and also the Kotlin/Native compiler for the supported platforms: Linux, macOS and Windows.

Changelog

Compiler

Performance Improvements

• KT-41149 NI: Upgraded project from 1.3.72 to 1.4.0 hangs during build
• KT-41335 Kotlin Out of Memory When evaluating expression
• KT-41400 NI: Huge performance regression for kotlin compiler from 1.3.72 to 1.4.0 due to using list of dozen lambdas in a call

Fixes

• KT-41005 Coercion to Unit doesn't take into account nullability of a return type for lambda
• KT-41043 NI: StackOverflowError throughPostponedArgumentInputTypesResolver.getAllDeeplyRelatedTypeVariables
• KT-41135 Type Inference Regression For Property Delegate With Receiver Type
• KT-41140 Unresolved reference to parameter of a catch block from lambda expression on 1.4.0
• KT-41150 IllegalStateException: Couldn't obtain compiled function body for public final inline fun
• KT-41164 NI: "IllegalStateException: Error type encountered" with callbackFlow builder inside condition
• KT-41202 Type inference fails in 1.4.0
• KT-41218 HMPP: arrayList declarations are visible both from stdlib-common and stdlib-jvm and lead to false-positive resolution ambiguity in IDE
• KT-41308 1.4.0 Type inference regression in suspend blocks with elvis operator expressions
• KT-41357 ClassCastException for unstable smart cast on a property call receiver
• KT-41386 NI: Type mismatch with generic type parameters
• KT-41426 Operator compareTo is not called with nullable type
• KT-41430 Broken choosing overload by lambda return type inside builder inference
• KT-41470 Wrong nullability assertion is generated when using the BuilderInference annotation
• KT-41482 Add a fallback compiler flag to disable the unified null checks behavior

IDE

• KT-41325 SOE in IDEKotlinAsJavaSupport
• KT-41390 Typo: equals & hashCode are written with the first uppercase letter

IDE. Code Style, Formatting

• KT-41314 Formatter: Frequent freezes when reformatting code (TrailingCommaPostFormatProcessor)

IDE. Debugger

• KT-40417 Coroutines Debugger: “No coroutine information found” in case of main() entry-point without explicit debug-artifact

IDE. Gradle. Script

• KT-39542 EA-218043: java.util.NoSuchElementException: No element of given type found (GradleBuildRootsManager)
• KT-41283 Gradle scripts unable to support 1.4 language level features yet

IDE. Inspections and Intentions

• KT-41264 Disable “Redundant inner modifier” in 1.4.10
• KT-41395 Inspection description misses a space (needs to be lowercase)

IDE. REPL

• KT-40898 REPL: "IllegalAccessError: tried to access field" caused by log4j

IDE. Wizards

• KT-38921 New project wizard: Backend/Console applications template with Groovy DSL generates build.gradle with KotlinCompile instead of compileKotlin

JavaScript

• KT-38059 Support arrays passed as named arguments to varargs
• KT-40964 KJS / IR: don't generate "import" (short names) for external interfaces
• KT-41081 KJS IR: nativeGetter, nativeSetter, nativeInvoke are not supported

Libraries

• KT-41320 Actual kotlin.test annotation typealiases are inaccessible in modular environment

Middle-end. IR

• KT-41324 IR: "Compilation failed: null" caused by StackOverflowError in compiler in multi-module project

Native. C and ObjC Import

• KT-39762 cinterop on 1.4-M2 doesn't include@deprecated Kotlin declaration for C declaration it fails to import

Native. ObjC Export

• KT-39206 New line characters in@deprecated annotation cause syntax error in Kotlin/native exported header
• KT-40976 "Unrecognized selector sent to instance" exception invoking suspending lambda from Swift in Native iOS project

Reflection

• KT-40842 "AssertionError: Built-in class kotlin.Any is not found" on java modular run

Tools. Compiler Plugins

• KT-41321 Upgrading to 1.4.0 fails compiling native with is not bound error

Tools. Gradle. Multiplatform

• KT-41083 Transitive dependency on an MPP with host-specific source sets fails to resolve: "Couldn't resolve metadata artifact..."

Tools. Gradle. Native

• KT-40834 Cannot build Kotlin Multiplatform project on Windows 10 64-bit when the Cocoapods plugin is applied

Tools. Scripts

• KT-35925 REPL: Springboot autoconfiguration problem (META-INF/spring.factories not found ?)

Tools. kapt

• KT-41313 kapt 1.4.0 throws "ZipException: zip END header not found", when Graal SVM jar in classpath

Checksums