Changelog

Analysis API. FIR

New Features

• KT-78090 Implement stubs support for new conditional returns and holdsIn contracts

Fixes

• KT-80485 False positive UNRESOLVED_REFERENCE on nested interface from super-super class in the super type position inside an anonymous object
• KT-82948 'FirRegularClass' expected as a containing declaration, got 'FirTypeAliasImpl'
• KT-82057 K2. Cannot infer type parameter 'R' in Ktor routing post() function with explicit response type
• KT-82772 Flaky false positive deprecation warning on PersistentMap.put in Kotlin repo in IDE mode
• KT-76487 StdLibSourcesLazyDeclarationResolveTestGenerated.testWrappedInt is unstable
• KT-82618 Various tests are failing with NPE in kt-master after updating the compiler on 19.11.25
• KT-82076 Error querying members of JavaClass created for SymbolLightClassForAnnotationClass during library analysis
• KT-71596 Include Js/Wasi checkers in AbstractLLFirDiagnosticsCollector
• KT-82085 No OUTER_CLASS_ARGUMENTS_REQUIRED on type parameter bound in IDE
• KT-81873 Provide a way of including traces in phase JFR events
• KT-71929 Consider leaving the non-post-compute version at EnhancementSymbolsCache.enhancedFunctions

Analysis API. Infrastructure

• KT-65140 LL FIR: Implement AbstractFirPsiJsDiagnosticTest for LL FIR
• KT-82212 [Analysis API, LL FIR] Implement AbstractDiagnosticsFirWasmTest and AbstractDiagnosticsFirWasmWasiTest for LL FIR

Analysis API. Light Classes

• KT-82227 Value classes should expose regular static methods

Analysis API. PSI

• KT-81710 'KtTypeReference.getTypeText' does not account for 'suspend' modifier on suspend lambdas
• KT-82258 Prepare PSI for migration from context receivers to context parameters
• KT-81074 KDoc: List rendering is broken

Analysis API. Providers and Caches

• KT-82449 K2 IDE Analysis Freezes During Gradle Sync (Recursive Module Dependency Computation in KotlinModuleDependentsProviderBase.computeTransitiveDependents)
• KT-82629 'collectDiagnostics' returns stale syntax error after editor fix
• KT-74907 Analysis API: Apply platform-based library module content restrictions consistently

Analysis API. Standalone

• KT-81107 AA: KtSourceModuleBuilder.sourceRoots doesn't works with symbolic links

Analysis API. Stubs and Decompilation

• KT-82792 Stub for KtValueArgumentList inside KtAnnotationEntry should be present if it is present in psi
• KT-82527 TypeClsStubBuilder.createFunctionTypeStub throws NullPointerException
• KT-82558 Deserialized DNN type should have a fully qualified Any
• KT-81928 KaArrayAnnotationValueImpl.values missing first element
• KT-82139 Support contracts for property accessors
• KT-82198 Support context parameters in contracts

Analysis API. Surface

New Features

• KT-82851 Property accessors should inherit KDoc from the parent property
• KT-63339 Analysis API: Provide a way to extract KDoc for symbols
• KT-79070 KaTypeProvider: add API to build a default type with star projections
• KT-66566 AA: api to create functional types
• KT-66043 KtTypeCreator doesn't provide a way for creating annotated types

Performance Improvements

• KT-81627 KaFirSymbolDeclarationOverridesProvider#processOverrides should process only relevant declarations

Fixes

• KT-68577 asPsiType and mapTypeToJvmType: leading delimiter for class in a root package
• KT-81734 MIssing "ARGUMENT_TYPE_MISMATCH" caused by self-referential generic type
• KT-82856 Redesign KotlinReferenceProviderContributor to make it extensible
• KT-82615 Clarify KtReference#resolvesByNames contract
• KT-82534 No expected type for property accessor without body
• KT-82406 Add a test to ensure that all top-level classes in the Analysis API Surface have Ka prefix

Backend. Native. Debug

• KT-81741 Native: stepping into data class hashCode in lldb goes to line 1

Backend. Wasm

New Features

• KT-81485 [Wasm] DebuggerCustomFormatters generation support for single module mode
• KT-81483 [Wasm] Typescript generation support for single module mode
• KT-81484 [Wasm] Dwarf generation support for single module mode

Performance Improvements

• KT-81524 Unnecessary Any-JsAny conversions are generated for external instanceofs

Fixes

• KT-79937 K/Wasm: support kotlin.js.nativeInvoke annotation
• KT-82202 [Wasm] SourceMap generation support for single module mode
• KT-82162 [Wasm] Run single module tests with standalone vm's
• KT-81325 [Wasm] Remove string pool initialiser dependent code
• KT-82645 K/Wasm: wasmJs use js "String" for number2String conversion
• KT-73238 K/Wasm: stop using linear memory inside our code
• Wasm: Compose application is not loading

Compiler

New Features

• KT-82467 Improve binary and JVM compatibility by generating bridges for abstract interface methods
• KT-74223 Move Kotlin/Native TestProcessor phase to the first phase
• KT-13968 Support vertx nullable annotation
• KT-79656 Use org.jetbrains.annotations.UnmodifiableView and/or org.jetbrains.annotations.Unmodifiable to infer read-only types for Java entities
• KT-27090 Support contracts in getter and setter for top-level extension properties
• KT-81684 Implement explicit passing of context arguments using named syntax [TEST_ONLY]

Performance Improvements

• KT-81974 Do not eagerly initialize reflection for KProperty objects for delegated properties
• KT-80061 Compiler (or IDEA) hangs due to importing large Kotlin reflect functions (e.g. KFunction999999999)
• KT-68592 Investigate performance implications of enabling -Xjvm-default for ir.tree module
• KT-71673 Consider making EnhancementSymbolsCache. enhancedFunctions using simple cache

Fixes

• KT-81951 K2: Another false positive "Assigned value is never read" in composable function
• KT-68606 Argument type mismatch, despite being from the same star-projected type
• KT-74051 Add a Continuation for tail-call suspend functions
• KT-5486 Better errors for integers with leading zero
• KT-83031 K2: unstable resolution of EnhancedNullability from type-use NotNull in presence of unused code
• KT-83153 Properly ignore contract statements in the Return Value Checker
• Refactor session component initialization for multi-target compilation

Compose compiler

• b/461766771 Fix IrSimpleFunction.isLegacyOpenFunctionWithDefault
• b/458234821 Disable Compose K1 tests on CI
• b/456948687 Force resolution of declarations when looking up SAM functions in FIR
• b/445426829 Add a diagnostic for key call with no arguments

IR. Actualizer

• KT-82418 KMP Separate Compilation: NPE caused by actualization of NsCalendar.getEra
• KT-82313 ACTUAL_ANNOTATION_CONFLICTING_DEFAULT_ARGUMENT_VALUE checks throw conflicting values in expected and actual annotations

IR. Inlining

Fixes

• KT-80791 classFunctionsAndFieldsWithCrossModuleInliner fails per-file with cross-module inliner
• KT-80696 Can not get instance of singleton 'Obj': No class found for symbol
• KT-81766 K/N: Recursive inline expect/actual causes StackOverflowError
• KT-80953 [Inliner] Eliminate excessive IMPLICIT_CAST after IR Inliner on 2nd stage.
• KT-82065 IR inliner: Inline function's default value argument may get wrong offsets in a temporary variable
• KT-81753 Review diagnosticReporters usage in pre-serialization lowerings
• Test fails per-file with cross-module inliner

IR. Interpreter

• KT-80646 Enable unsigned conversion functions when bootstrapped compiler is available

IR. Tree

• KT-82829 IR deserializer: Don't deserialize any fake overrides from Klibs
• KT-80243 Support Name Based Destructuring in loop with withIndex()
• KT-79436 KLIB stdlib symbols loading: Drop all functions from SymbolFinder except for loading the whole collection of (potentially unbound) symbols by name
• KT-79435 KLIB stdlib symbols loading: Load symbols and and filter/map them lazily in BuiltinSymbolsBase hierarchy when accessed by IR
• KT-69082 Migrate maps of IR elements to IR attributes
• KT-67457 Introduce a way to simplify IR lowering phase creation

JVM. Reflection

New Features

• KT-22265 Support for inherited annotations

Fixes

• KT-81024 Reflection: New KType implementation fails on arguments comparison for a Nothing type parameter
• KT-57357 Reflection: "KotlinReflectionInternalError" when using callBy on constructor that has inline class parameter with nullable value
• KT-82699 Reflection: incorrect behavior of KFunction.isExternal for Java native methods
• KT-82350 Reflection: incorrect behavior of KType.javaType on a type obtained from KType.withNullability
• KT-29203 KType.javaType always returns void class for local delegated property
• KT-81899 Reflection: incorrect javaType for local delegated property setter return type

JavaScript

New Features

• KT-54504 K/JS: Support ECMAScript tagged string templates
• KT-82327 KJS: Export parameter names of function types if present in .d.ts files
• KT-82371 KJS: Generate more concrete TypeScript for members of an uninhabited enum

Performance Improvements

• KT-16379 KotlinJs - ArrayList get is now slow

Fixes

• KT-67460 Use new lowering phase creation API in JS backend
• KT-82667 Kotlin/JS: ESM TypeScript definitions for exported nested Enums do not compile
• KT-82553 KJS: Incorrect .d.ts generated for generic inner classes
• KT-82652 KJS: Exported abstract inner classes can be constructed from TypeScript
• KT-82542 KJS: Inner class can be constructed from TypeScript without passing an outer instance
• KT-82499 KJS: Omit parameters in private constructors in .d.ts files
• Implement exporting top-level properties in Analysis API-based TypeScript Export

Klibs

New Features

• KT-83101 Implement experimental KLib ABI dump parser

Fixes

• KT-81466 Enable KlibAnnotationsInMetadata by default in LV 2.5
• KT-83071 Failure on Native Nightly
• KT-78365 [PL] Change the behavior of getting name of removed function
• KT-81977 Klib compatibility tests: Implement sanity checks
• KT-81410 Klib metadata: migrate to using the common annotations instead of klib-specific extensions in kotlinx-metadata-klib
• KT-82577 Don't use KLIB resolver in the KLIB tool
• K/Wasm: allow using newer stdlib with older compiler

Language Design

• KT-73502 Context parameters: it is not possible to declare local function with a context

Libraries

• KT-78115 Investigate the current situation with 22 kotlin.context standard library overloads
• KT-83026 Specify compareTo behavior for Boolean
• KT-79093 Expose FirResolvedStatus.hasMustUseReturnValue in kotlin-metadata
• KT-82868 Restore accidentally deleted JS-specific note in ArrayList documentation
• KT-81563 Document kotlin.collections.HashMap and HashSet
• KT-82363 Add assertIs to the list of ignorable functions
• Document kotlin.collections.ArrayList

Native

• KT-81828 Update exception messages regarding disabling native cache
• KT-75806 KN Compiler with debug build can not produce executable with debug info
• KT-81495 Consider making Kotlin/Native distribution compiler cache reproducible
• KT-82387 Kotlin <-> Xcode compatibility issue
• KT-81501 Make Kotlin/Native distribution runtime .bc and fingerprint reproducible
• KT-80790 'Argument list too long' error when using dynamic_caches
• ExceptionInInitializerError when configuring Gradle project with kotlin-multiplatform plugin on a host unsupported by Kotlin/Native

Native. Build Infrastructure

• KT-82886 KonanTarget's clinit causes deadlock
• KT-81345 Temporary turned off Swift Export execution tests
• KT-80869 Extract per-module test generators for Native tests
• KT-82028 Kotlin/Native: move runtime building flags to runtime building code
• KT-81500 Make Kotlin/Native distribution shared libraries reproducible
• KT-72011 Kotlin/Native: consider building platform libraries with bootstrap compiler
• Kotlin/Native: build stdlib with the bootstrap compiler

Native. C and ObjC Import

• KT-79741 Native: implement type checking against Objective-C protocols without protocolGetter
• KT-83039 Native: mark header-defined functions and globals unavailable with -Xccall-mode direct
• KT-82200 Native: implement type checking against Objective-C protocols with objc_runtime_name without protocolGetter
• KT-82669 Kotlin/Native: cinterop tests failure with no class for metaclass
• KT-79742 Native: import C global variables without C wrappers
• KT-81937 Native: switch cinterop to by default for custom cinterop klibs

Native. ObjC Export

• KT-82160 K/N: bridge for fake override is not built but requested
• KT-83014 Native: experimental support for generating an NS_ENUM in addition to an Objective-C class for Kotlin classes
• KT-76637 ObjCExport: K1 + K2 integration test

Native. Runtime

• KT-82077 Kotlin/Native: in runtime make main module depend on mm module

Native. Runtime. Memory

• KT-81152 Kotlin/Native: deprecate isMemoryLeakCheckerActive
• KT-81156 Kotlin/Native: deprecate forceCheckedShutdown

Native. Swift Export

• KT-82908 Swift Export: bridges for FT should be recursive
• KT-82907 Swift Export: attributes are not printed for parameters of closures
• KT-80971 Swift Export: Support exception throwing
• KT-80970 Swift Export: Support cancellation
• KT-82726 Swift Export: filters out wrong module for coroutines
• KT-81591 Custom type translation rules in Swift export
• K/N - Build fails when exposing suspend functions

Tools. BCV

• KT-80747 Refactor API of ABI tools [ABI Tools]
• KT-80938 Binary compatibility validation: can't exclude container types of Repeatable annotations by filters.excluded.byNames

Tools. Build Tools API

New Features

• KT-81845 Add CRI <-> Maven integration
• KT-81847 Add CRI <-> BTA integration
• KT-80338 Kotlin CRI generation
• KT-80681 BTA: introduce a special argument for passing compiler plugins
• KT-82167 Add BuildTimeMetric for the CRI data generation
• KT-81846 Add FUS for CRI usage in Gradle / Maven

Fixes

• KT-82682 BTA: reading non-nullable arguments may return null or throw NPE
• KT-81887 Implement the CRI lookup data generation
• KT-81886 Implement the CRI data serialization
• KT-81780 Add Gradle <-> CRI integration tests
• KT-81645 BTA prints unreadable version in "option available only since" error (shows KotlinReleaseVersion@hash instead of 2.x.y)

Tools. CLI

• KT-73606 Provide a unified interface for managing the reporting of compiler warnings
• KT-48419 Using a @RequiresOptIn API that does not exist should have an option to not output a warning
• KT-81861 Introduce a mechanism that allows suppressing CLI diagnostics
• KT-82321 KMP Separate Compilation: Common fragments are missing forward declaration symbol providers
• KT-81898 Introduce a CLI option to disable source file sorting
• KT-81551 Introduce an experimental CLI option for enabling local type aliases
• Remove patched copy of com.intellij.util.lang.JavaVersion from the Kotlin repo

Tools. CLI. Native

• KT-64509 Refactor Kotlin/Native compiler setup: run FE without KonanConfig

Tools. Compiler Plugin API

• KT-82809 [FIR][IC] New containingFileName parameter API is not actually compatible with IC
• KT-46709 IR plugin lookups don't work as expected for expect class with actual typealias
• KT-82518 Disable automatic body generation of the plugin-generated callables
• KT-82159 [FIR] Automatically add expressions to properties or functions
• KT-58886 K2: compiler plugin generated top level declarations cause AssertionError on K/JS and K/Native

Tools. Compiler Plugins

• KT-82341 Migrate official compiler plugins to IC-safe reference... API
• KT-81604 Lombok Kotlin compiler plugin and -Werror: Unable to ignore warning for the plugin appliance
• KT-71893 Support @Builder lombok annotation on methods

Tools. Compiler plugins. Serialization

• KT-82351 Migrate kotlinx.serialization to IC-safe reference... API
• KT-76949 Serialization: "IllegalStateException: Serializer for element of type kotlin.Any has not been found" on custom serializer for Map<String, Any?>
• KT-73107 Serialization: "IllegalStateException: Serializer for element of type kotlin.Any? has not been found" with star projection

Tools. Gradle

New Features

• KT-78200 Gradle: enable JVM compilation through BTA by default
• KT-81844 Add CRI <-> Gradle integration

Fixes

• KT-80096 Strange "Inconsistent JVM Target Compatibility" warning
• KT-81831 Verify Problems API implementation with Gradle guidelines
• KT-80120 Support colored value for --console command in Gradle 9.1
• KT-81400 ToolingDiagnosticFactory: check if documentationLink set multiple times
• KT-83070 The KGP api reference is missing a description
• KT-82459 Improve iOS simulator boot implementation
• Deprecate LanguageSettings.enableLanguageFeature DSL

Tools. Gradle. BCV

• KT-80674 Rename tasks to avoid using legacy word [ABI Validation]
• KT-80827 Delete DSL for working with dump variants [ABI Validation]
• KT-80823 Stabilize DSL for filtering [ABI Validation]

Tools. Gradle. Cocoapods

• KT-80641 EXECUTABLE_DEBUG_DYLIB_PATH problem
• KT-80644 Cocoapod plugin builds a synthetic project for "generic/platform=iOS Simulator"

Tools. Gradle. JS

• KT-82946 Js, Wasm: Upgrade NPM dependencies

Tools. Gradle. Multiplatform

• KT-81944 Legacy KMP Android uses wrong configurations to infer common dependencies
• KT-81536 "Couldn't resolve dependency in 'commonMain' for all target platforms" in 2.2.20-Beta2
• KT-81724 IntelliJ successfully resolves imports that are not actually available in the given module
• KT-81849 Replace kotlin-test-common and kotlin-test-annotations-common with just kotlin-test
• KT-79073 compileTest* tasks pass separateCompilation parameters but don't behave accordingly
• KT-71130 Enable Isolated Projects support by default for KMP

Tools. Gradle. Native

• KT-80715 Deprecate kotlin.native.cacheKind and introduce DSL instead
• KT-81443 ConfigurationCacheError on Linux arm64 due to disabled iOS targets

Tools. Gradle. Swift Export

• KT-82727 Swift Export: generated kotlin bridges don't see neighboring modules

Tools. Gradle. Wasm

• KT-82525 K/Wasm: kotlinToolingSetup does not depend on package manager installation

Tools. Incremental Compile

• KT-80483 Incorporate IC lookups into reference... methods of IrPluginContext

Tools. JPS

• KT-76927 Switching from VAL to VAR does not trigger recompilation of usage in Kotlin-uses-Kotlin
• KT-79362 JPS/NoArg: Failed to build project with 'java.lang.NoClassDefFoundError: org/jetbrains/kotlin/com/intellij/psi/PsiElement'

Tools. Kapt

• KT-82338 K2 KAPT: ISE "Cannot evaluate IR expression in annotation" on unresolved enum usage
• KT-81691 K2: KAPT: "ClassCastException: IrErrorTypeImpl cannot be cast to class IrSimpleType"

Tools. REPL

• KT-82575 [K2 REPL] Redesign frontend resolution for REPL snippets

Tools. Scripts

• KT-81679 Script explain: while loop explanation may lead to the hanging code
• KT-81677 Script explain: Contents of the if/when branches are not explained
• KT-67063 LauncherReplTest flaky on Windows

Tools. Statistics (FUS)

• KT-79576 Included build subprojects produce FUS files with unknown_id when configuration cache is enabled