2.3.21

Backend. Wasm

• KT-84610 [Wasm] Failed to compile klibs in IC mode

Compiler

• KT-84566 Prevent launching Default dispatcher threads from IJ SDK in kotlin compiler
• KT-85358 Native: roll back the workaround for KT-84678 once MapLibre has been properly fixed
• KT-85626 @JvmRecord in commonMain breaks compileCommonMainKotlinMetadata with “Cannot access ‘java.lang.Record’”
• KT-85405 Postpone/Revert DontIgnoreUpperBoundViolatedOnImplicitArguments
• KT-84678 K/N: Undefined symbol from SPM-added ObjC frameworks when linking iOS target
• KT-85021 False positive SUBCLASS_CANT_CALL_COMPANION_PROTECTED_NON_STATIC error in multi-module project

JavaScript

• KT-82395 Support top-level declarations from compiler plugins in JS incremental compilation
• KT-84475 K/JS: false-positive exportability warnings in multi-module project
• KT-84633 Kotlin/JS: “Serializer for class not found” error when IR output granularity is whole-program
• KT-85047 Kotlin/JS: @JsStatic on suspend fun of class companion generates incorrect d.ts
• KT-84517 K/JS: bad mappings data in outputted Kotlin stdlib source map

Libraries

• KT-71848 Kotlinx.metadata: Add CompilerPluginData into Km API

Native. C and ObjC Import

• KT-85399 Kotlin/Native: TypeCastException when casting ObjC Protocol MetaClass with genericSafeCasts enabled
• KT-85508 K/N: TypeCastException when using nw_parameters_create_secure_tcp block parameter on 2.3.20

Tools. Gradle

• KT-84729 Update Gradle plugin-publish version to enable configuration cache badge on Gradle plugins portal

Tools. Gradle. Compiler plugins

• KT-85257 AGP/Compose: MergeMappingFileTask clears R8 artifacts due to @OutputDirectory annotation on AGP 9.1+

Tools. Scripts

• KT-85105 Scripts: JVM backend internal error (IR lowering) when scratch file contains anonymous object
• KT-85103 Exception while generating code when explain destructuring decls
• KT-84842 scriptCompilationClasspathFromContext behavior changed from 2.3.10 to 2.3.20
• KT-85029 Kotlin Scripting: ScriptDiagnostic reports “at null” instead of error location

Tools. Statistics (FUS)

• KT-85628 KGP: composite build FUS metrics fail on access of ‘configurationTimeMetrics’

2.3.20

Analysis API. FIR

New Features

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

Fixes

• KT-82948 ‘FirRegularClass’ expected as a containing declaration, got ‘FirTypeAliasImpl’
• KT-83467 Package-level JSpecify annotations are ignored when coming from jars or libraries
• KT-82057 K2. Cannot infer type parameter ‘R’ in Ktor routing post() function with explicit response type
• KT-82846 AA: unresolved KtExpression.expressionType for the reference to the parameter with default value
• KT-80485 False positive UNRESOLVED_REFERENCE on nested interface from super-super class in the super type position inside an anonymous object
• 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-83173 Analysis API Tests: Library names with RC versions aren't sanitised
• 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-83694 Provide psi-based implementation of KaDeclarationSymbol#isExternal
• KT-70868 KaSymbol: support PSI-only visibility and modality for the case without compiler plugins
• KT-81627 KaFirSymbolDeclarationOverridesProvider#processOverrides should process only relevant declarations

Fixes

• KT-83152 [Analysis API, KDoc] Make class name links on constructors point to the class
• KT-83695 Deprecate KaSymbolInformationProvider#{getter, setter}DeprecationStatus
• KT-82853 Add a convenience property for testing declarations for effective external-ness
• KT-83226 Support “Collection literals” in the Analysis API
• KT-83225 Support “@IntroduceAt” in the Analysis API
• KT-83222 Support “Improve use-site defaulting for annotations” in the Analysis API
• KT-83351 Rename KaSession context parameter from ‘s’ in bridges to something nicer
• KT-83199 Clarify API around extension points
• KT-83074 Inner enum entry class has incorrect default visibility
• KT-82442 Add Ka prefix to org.jetbrains.kotlin.analysis.api.symbols.AdditionalKDocResolutionProvider
• KT-82443 Add Ka prefix to org.jetbrains.kotlin.analysis.api.symbols.DebugSymbolRenderer
• KT-82441 Add Ka prefix to org.jetbrains.kotlin.analysis.api.compile.CodeFragmentCapturedValue
• KT-82439 Add Ka prefix to org.jetbrains.kotlin.analysis.api.components.DebuggerExtension
• KT-82438 Add Ka prefix to org.jetbrains.kotlin.analysis.api.components.DefaultTypeClassIds
• 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
• KT-78397 investigate if there is a need in Extra support for the “various little features in contracts”
• KT-74009 Analysis API: Expose “isOverloadable” check for callable symbols similar to “OverloadChecker.isOverloadable”
• KT-78399 Check return value - check how we see from Java(+Stub) we see “annotated” signatures
• KT-80357 [Analysis API] KaType.enhancedType doesn't enhance type parameters
• KT-73659 Analysis API: The name of KaType.enhancedType is too general
• KT-80545 [Analysis API] Deprecate KaFunctionType.arity
• KT-77708 K2 Mode: Potentially redundant smart cast highlighing when passing smartcasted expressions as arguments
• KT-81264 K2 AA: KaValueParameterSymbol.hasDefaultValue is false for overriding or actual functions
• KT-81166 Forbid the usage of KaSessionComponent implementation types directly
• KT-74801 Analysis API: Publish/subscribe to modification events with a single message bus topic

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-83839 K/Wasm: CMP. Load time on Safari significantly increased with Kotlin = 2.3.20-Beta1
• KT-81524 Unnecessary Any-JsAny conversions are generated for external instanceofs

Fixes

• KT-82732 K/Wasm runtime crash when using fun reference: convertKotlinClosureToJsClosure
• KT-82649 K/Wasm: Rewrite StringBuilder to use JsString
• KT-73240 K/Wasm: consider using JS String Builtins proposal in String implementation for wasm-js target
• KT-83995 K/Wasm: 2.3.0 -> 2.3.20-Beta1 degradation in arrow tests
• KT-82309 K/Wasm: refactor _initialize function
• KT-70075 Wasm: “OutOfMemoryError: GC overhead limit exceeded” during tests
• KT-83046 K/Wasm: don't use StringBuilder implicitly for string concatenations
• KT-82645 K/Wasm: wasmJs use js “String” for number2String conversion
• KT-79937 K/Wasm: support kotlin.js.nativeInvoke annotation
• KT-67461 Use new lowering phase creation API in Wasm backend
• KT-83664 Wasm: Colon and space are not sanitized in output file names
• KT-65779 JsExport declaration name clash
• 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-73238 K/Wasm: stop using linear memory inside our code
• KT-83025 Wasm: Compose application is not loading
• KT-73239 K/Wasm: use JS String Builtins proposal to transfer strings to and from JS
• KT-83194 K/Wasm: create WasmIR test infrastructure
• KT-65234 K/Wasm Ensure that fp operations are aligned with other b-ends
• KT-81856 K/JS/Wasm interop: external instanceofs do not link in singleModule mode
• KT-81610 [Wasm] Add CLI test for performance metrics for klibs->binary scenario
• KT-81550 Incorrect generation of .wat files
• KT-71533 K/Wasm + K2: no error on KClass::qualifiedName usages

Compiler

New Features

• KT-75736 Enable reading/writing annotations in metadata on JVM by default
• KT-79330 Implement the first version of inference for Collection Literals
• KT-83401 Collection literals: support different types of expected types for CL
• KT-55548 JSR-305: Overload resolution ambiguity: Platform Types vs Kotlin Types
• KT-74860 Support Unit coercion (incl. fun refs) in unused return value checker
• 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-81684 Implement explicit passing of context arguments using named syntax [TEST_ONLY]
• KT-80492 Checkers for operator of
• KT-82638 Collection literals: resolve to factory functions for standard library classes
• KT-82467 Improve binary and JVM compatibility by generating bridges for abstract interface methods
• KT-82655 Bridges generated for non-fake overrides shall include annotations from target methods
• KT-74223 Move Kotlin/Native TestProcessor phase to the first phase
• KT-27090 Support contracts in getter and setter for top-level extension properties
• KT-74809 Support unnamed local variables
• KT-45683 Allow generics in contract type assertions

Performance Improvements

• KT-81974 Do not eagerly initialize reflection for KProperty objects for delegated properties
• KT-83697 Native: increased bitcode produced with enabled safe casts
• KT-83036 Native: too many casts emitted with -Xgeneric-safe-casts=true
• 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-73687 Inefficient KtCommonFile#getFileAnnotationList
• KT-71673 Consider making EnhancementSymbolsCache. enhancedFunctions using simple cache

Fixes

• KT-84773 Annotations not persisted in IR for internal external functions
• KT-78783 K2: absence of warning for KTLC-284 migration
• KT-81553 INITIALIZER_TYPE_MISMATCH and ASSIGNMENT_TYPE_MISMATCH is reported on the entire initializer
• KT-83395 Kotlin/Native 2.3.0 iOS release framework fails with Invalid LLVM module (PHI node type mismatch)
• KT-84620 Incorrect optimization of property delegation
• KT-81567 Add a use-site warning if a @DslMarker-marked annotation is used on entities where it is a no-op
• KT-81700 flaky overload resolution behaviors (false-positive errors, different final candidates, compile-time failures)
• KT-83372 compileDebugKotlinAndroid hangs in 2.3.0 with SQLDelight
• KT-82579 Update specificity rule for context parameters
• KT-83590 Some explicit backing fields must still be considered private-to-this
• KT-83849 False-positive NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS for Optional.orElse(null) call
• KT-84192 “Member overrides different ‘@Throws’ filter from” caused by overriding in different module
• KT-72994 K2: Remove resolution to context receivers
• KT-80247 No diagnostic on unresolved type annotation from a dependency in an inferred type
• KT-78730 Move more LLVM-agnostic code to compiler/ir/backend.native or compiler/ir/backend.common
• KT-74051 Add a Continuation for tail-call suspend functions
• KT-83984 Data races around kotlinx.serialization plugin protobuf extensions registration
• KT-83317 ClassCastException: with cast kotlin.UInt to java.lang.Number when defining constant
• KT-83031 K2: unstable resolution of EnhancedNullability from type-use NotNull in presence of unused code
• KT-83824 Delegated property in Gradle DSL fails to compile
• KT-83657 [K/N] Pre-codegen inline produces invalid bitcode
• KT-81555 Kotlin scripts: top-level name-based destructuring with _ = prop fails with “exception while generating code”
• KT-83314 JSpecify @NullMarked changes Java equals(Object) to equals(Any?) causing override conflict in Kotlin 2.3
• KT-83282 JvmExposeBoxed: Duplicate annotation interface kotlin.coroutines.jvm.internal.DebugMetadata in class %class%$1 for suspend inline class value
• KT-78443 Refactor session component initialization for multi-target compilation
• KT-83427 Arguments of plugin-generated annotations are serialized incorrectly
• KT-83538 OPERATOR_RENAMED_ON_IMPORT is not reported for ‘provideDelegate’ operator
• KT-83537 OPERATOR_RENAMED_ON_IMPORT is not reported for ‘of’ operator
• KT-82721 Inconsistent explicit backing fields behavior
• KT-83589 Explicit backing fields don't likely work with intersection overrides
• KT-81951 K2: Another false positive “Assigned value is never read” in composable function
• KT-83588 Explicit backing field is falsely accessible from a subclass via a substitution override
• KT-82849 Collection literals (minor): collection literal should only be resolved to operator
• KT-83363 VerifyError: “Bad type on operand stack” on multi-line suspending call with default parameter value since API version 2.4
• KT-83570 K2: Resolve problematic IR when referencing Kotlin const from annotation in Java
• KT-83362 Starting from 2.3 DefaultImpls bridge functions deprecated with the level HIDDEN are no longer synthetic
• KT-9182 Java interoperability: Overload resolution ambiguity on Java's @NotNull and primitives
• KT-83633 Forbid inline functional context parameters in inline functions
• KT-83449 compile-time IR failure on smart cast information leaking from capturing closure
• KT-82375 Add ATOMIC_REF_WITHOUT_CONSISTENT_IDENTITY warning for any argument without consistent identity
• KT-82524 Access to a companion that requires opt-in is possible without opt-in
• KT-83367 VolatileFieldsLowering may emit wrong parameter types for atomic intrinsic calls
• KT-83382 K2: Unreachable method exit breaks MUST_BE_INITIALIZED checks for succeeding value declarations
• KT-82211 False positive SENSELESS_NULL_IN_WHEN with nullable var
• KT-83157 ExplicitBackingFields: “Property with explicit backing field should be final” in 2.3.0
• KT-83269 K2: Wrong types in IR for explicit backing fields
• KT-68606 Argument type mismatch, despite being from the same star-projected type
• KT-83324 Native: problem with loops handling in types computation pass
• KT-83241 K2: “NoSuchElementException: List is empty” with top-level destructuring declaration and lambda initializer
• KT-82277 Misleading Inapplicable candidate(s): fun <K> WHEN_CALL(vararg branches: K): K when a when expression branch contains an unresolved reference
• KT-80839 Get rid of an obsolete -Xcompile-builtins-as-part-of-stdlib flag once previous changes are bootstrapped
• KT-82900 Language Feature EnhancedBridgesGeneration
• KT-82651 Do not generate self-recursive bridges in JVM backend
• KT-5486 Better errors for integers with leading zero
• KT-83185 Kotlin repeatable annotations are incorrectly deserialized from bytecode
• KT-82863 @NoInfer regression since 2.2.20
• KT-82376 Header mode: Index out of bounds when generating bodies of data class
• KT-82311 Header mode: Error expression when assigning function declaration to a property
• KT-82408 Header mode: Java files are not compiled successfully
• KT-82378 Header mode: Sequence contains no element matching the predicate
• KT-82407 Header mode: Backend Internal error: Exception during IR lowering
• KT-81763 Incorrect comparison result when using elvis ?: with nullable Long values
• KT-83153 Properly ignore contract statements in the Return Value Checker
• KT-83076 Don't report WRONG_JS_INTEROP_TYPE on expect types during metadata compilation
• KT-78589 “Class does not have member field” caused by delegation from a Java to Kotlin class
• KT-82640 K2: CCE on green code
• KT-82684 “Don't know how to compile annotation value ERROR_EXPR” on incorrect array literal in annotation default arguments
• KT-81948 K2: ClassCastException: “java.lang.String cannot be cast to java.lang.Void” when calling @Nullable Java function
• KT-82788 false-positive duplicate JVM class name error in IJ monorepo
• KT-82841 “kotlin.NoWhenBranchMatchedException” in when with !is check & non-sealed class in the middle of hierarchy
• KT-82844 “when” with no branches does not evaluate subject (side effects ignored)
• KT-81625 Incorrect empty parameters parsing (comma is highlighted in red)
• KT-81193 K2: SOE from AbstractTypeApproximator.approximateToSuperType with local enum class
• KT-65059 Stack overflow when typechecking an Elvis expression with deeply generic values
• KT-82555 @Deprecated(HIDDEN)` objects not skipped when resolving qualifiers
• KT-82737 Leaked type variable in diagnostic when top-level lambda with uninferred type parameter has non-functional expected type
• KT-78019 Change K1 API deprecation level from Warning to Error
• KT-82683 K2: FIR2IR: compile-time JVM codegen failure on an argument of function subtype for a KSuspendFunction parameter
• KT-82671 Do not report ignorability mismatch on override/actualization if the function returns Unit type
• KT-82506 Misleading compilation warning: “This class is not recommended for use in Kotlin. Use ‘java.util.Map’ instead”
• KT-52498 Test privateSuperType.kt is failing with caches enabled
• KT-82336 Header mode: Cannot infer argument for type parameter T
• KT-69326 Inference chooses controversial order to fix variables
• KT-82545 Handle data class with extra components in migration warning for name-based destructuring
• KT-82303 Improve UNSUPPORTED_FEATURE message when compiler argument has a parameter
• KT-81866 K2: False positive ILLEGAL_RESTRICTED_SUSPENDING_FUNCTION_CALL caused by smart-casted @RestrictsSuspension receiver
• KT-13412 Improve error message on callable reference with expression of nullable type
• KT-82466 KotlinIllegalArgumentExceptionWithAttachment when return is used in explicit delegation expression
• KT-82454 Local types aren't approximated in public declaration types
• KT-82487 False positive REDUNDANT_VISIBILITY_MODIFIER inside private class
• KT-82369 [K2 REPL] Crash in the serialization plugin backend with “unable to transform declaration”
• KT-82243 Usage of nested type aliases is forbidden despite the feature flag
• KT-62900 K2: Expected expression to be resolved during Fir2Ir
• KT-81941 IllegalArgumentException: class org.jetbrains.kotlin.psi.KtValueArgument is not a subtype of class org.jetbrains.kotlin.psi.KtExpression for factory POSITIONED_VALUE_ARGUMENT_FOR_JAVA_ANNOTATION
• KT-80741 Fix rendering of inner classes with generic outer classes
• KT-82331 Do not propagate context parameters from classes to constructors
• KT-77276 K2: Wrong scope for annotation arguments for the parameters of a secondary constructor header
• KT-77275 Inconsistency between scopes for primary/secondary constructor headers
• KT-15152 Improve error message for unresolved reference for delegation specifier and primary constructor call
• KT-81498 Make Kotlin/Native stdlib in distribution reproducible
• KT-81408 Allow local-variable-target annotations on destructuring declarations
• KT-82012 Annotations without parentheses on full form of name-based destructuring don't work
• KT-81915 Exception when analysing ‘when’ expression with annotated expression as a subject
• KT-78364 Static methods are not generated for companion object JvmStatic property accessors with JvmExposeBoxed
• KT-81838 Prohibit usage of nested type aliases (from lib) for sources with LV < 2.3
• KT-81357 Forbid compilation of code with explicit root_ide_package in CLI mode
• KT-73138 K2: “Assignment type mismatch” when class name is underscore_
• KT-82169 Add quotes to message of WRONG_NUMBER_OF_TYPE_ARGUMENTS
• KT-78386 JvmExposeBoxed (with no name) + JvmOverloads + JvmName produces ambiguity
• KT-78358 Propagated JvmExposeBoxed annotation doesn't copy JvmName argument
• KT-81699 Move native klib compilation to a separate module
• KT-81692 Decouple compilation of Native klib from the Native backend
• KT-80673 Consider forbidding/minimizing usages of ClassId.isLocal and CallableId.isLocal
• KT-81376 False negative UNEXPECTED_TRAILING_LAMBDA_ON_A_NEW_LINE & bad positioning
• KT-81946 false-positive JAVA_CLASS_ON_COMPANION in case of an explicit companion reference
• KT-74461 K2: Render function types nicely
• KT-81875 NCDFE: kotlinx/coroutines/internal/intellij/IntellijCoroutines at :compiler:multiplatform-parsing:jvmTest
• KT-49722 Report NOT_YET_SUPPORTED_IN_INLINE for inherited default parameters with inline function
• KT-81913 Inapplicable candidate when vararg-adaption for callable reference might be used (array parameter)
• KT-81841 Inapplicable candidate when vararg-adaption for callable reference might be used (generic parameter)
• KT-39697 “Cannot infer type parameter” in map with java static or global method reference
• KT-81896 Improve RedundantCallOfConversionMethod inspection for @UnsafeNumber annotated typealiases
• KT-66413 Incorrect line mapping in suspendable code before suspend call without parameters
• KT-80525 Update IntelliJ SDK dependency to 251.27812.49
• KT-81808 Setting hasDefaultValue = true in irValueParameter() crashes the compiler
• KT-78927 False positive ‘USELESS_JVM_EXPOSE_BOXED’
• KT-81703 Drop obsolete K1 frontend code from Kotlin/Native
• KT-81698 DecoupleSpecialBackendChecksTraversal from Native backend
• KT-81687 Different LightTree and PSI outputs when annotated class-like declaration is used as an expression
• KT-81302 False positive: Type Mismatch caused by context parameters, lambdas, and generics
• KT-81584 IAE “Collection contains more than one matching element” in FirElementSerializer on contextual property with same name as primary value class property
• KT-77237 JvmExposeBoxed breaks compilation with a secondary constructor with value class
• KT-81262 False positive: Access declaration type exposure: during access to public function class from internal inline declaration
• KT-80112 Kotlin Debugger: “Cannot find local variable” on evaluating default lambda inside inline function
• KT-76806 K2: AIOOBE in FirEqualityCompatibilityChecker
• KT-81693 Introduce lightweight versions of KonanConfig and PhaseContext
• KT-72446 K/N: inline function‘s default values aren’t lowered with caches
• KT-81521 Anonymous function in context parameters breaks parser
• KT-80853 Class reference in context parameters breaks parser
• KT-81441 Missing type checks when class has deeply generic supertype
• KT-79116 Wrong parameter arguments mapping (compiler skips empty arguments)
• KT-81422 False negative in full-form name-based destructuring: annotations before val/var not rejected
• KT-80652 K2: USELESS_IS_CHECK is not detected in when
• KT-80049 Mangle ERROR_TYPEs in diagnostics reported to user
• KT-73786 Evaluator: cannot evaluate inline methods with reified parameter
• KT-75828 Store backing field/delegate annotations and extension receiver annotations in metadata
• KT-74572 Context parameters: contracts don't work with context parameters
• KT-42824 FIR: false INAPPLICABLE_CANDIDATE when using in variance on a Java class

Compose compiler

• b/481953005, b/481769383 Cache stability inference results during session
• b/481735904 Fix Compose codegen crash in inline function
• b/479646393 Add groups to inline functions with two or more inline parameters
• 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-82017 [Inliner] Inline function overrides abstract method with default value
• KT-80814 [IR Inliner] Space: jsBrowserProductionWebpack task failed with HookWebpackError
• KT-83280 Split LibrarySpecialCompatibilityChecksTest into pure JS and pure Wasm tests
• KT-81766 K/N: Recursive inline expect/actual causes StackOverflowError
• KT-80953 [Inliner] Eliminate excessive IMPLICIT_CAST after IR Inliner on 2nd stage.
• KT-79899 [IR Inliner] Split single-module tests having inline fun into files
• KT-83148 KLIB inliner: Make both “inliner” language features to require Api Version = 2.3
• 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-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
• KT-80793 Test friendDependencyWithCrossModuleInliner fails per-file with cross-module inliner
• KT-80698 [IC][WASM] Mismatched file stats
• KT-80697 [IC][JS per file] Mismatched rebuilt modules
• KT-80660 [Inliner] Bodyless functions should not be inlined at 1st compilation stage
• KT-79064 Try to get rid of TypeOfPostProcessor

IR. Interpreter

• KT-82161 Enable Enum.name and KCallable.name to constant evaluation
• KT-80646 Enable unsigned conversion functions when bootstrapped compiler is available

IR. Tree

• KT-82765 Kotlin/Native: Internal compiler error when building DFG
• KT-82829 IR deserializer: Don't deserialize any cinterop fake overrides from Klibs
• KT-83236 PeopleInSpace_mpp compilation error: The symbol table has been sealed
• KT-81154 [IrValidator] Fine-tune IrVisibilityChecker on 2nd stage
• 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

Performance Improvements

• KT-84600 Performance regression around Kotlin properties JVM reflection during instantiation

Fixes

• KT-83608 Kotlin-reflect: “Unknown origin of public abstract operator fun invoke(p1: P1, p2: P2): R”
• KT-57357 Reflection: “KotlinReflectionInternalError” when using callBy on constructor that has inline class parameter with nullable value
• KT-83361 “KotlinReflectionInternalError: Type parameter not found: 0” on super types with Kotlin 2.3.0
• KT-42199 “KotlinReflectionInternalError: Unknown origin of public abstract operator fun invoke” on function reference to FunctionN.invoke
• KT-81024 Reflection: New KType implementation fails on arguments comparison for a Nothing type parameter
• KT-83067 Reflection: IAE “argument type mismatch” on callBy with vararg of generic type parameter with primitive upper bound
• 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
• KT-82093 Reflection: IAE from defaultType for inner class of generic class
• KT-77312 KotlinReflectionInternalError: “Container of deserialized member is not resolved” on computing type parameter captured in a local delegated property
• KT-82316 Reflection: type parameters of top-level declarations behave incorrectly
• KT-81987 Reflection: error when calling function in inline class with inherited default value
• KT-81870 Reflection: Error when calling function with default parameters and extension receiver
• KT-81880 Reflection: Error when calling function with default & context parameters
• KT-81907 Reflection: incorrect result when calling function with default values and context parameters
• KT-81859 Reflection: do not use descriptors in ValueClassAwareCaller
• KT-81854 Reflection: incorrect type for instance receiver of inner class constructor
• KT-81855 Reflection: IAE “object is not an instance of declaring class” on function with context and extension receiver of inline class
• KT-81843 Reflection: NPE on accessing property accessor returnType for Java field
• KT-81588 Reflection: KotlinReflectionInternalError “Inconsistent number of parameters” on calling contextual declaration with value class type in the signature
• KT-81111 Reflection: suspend function types are loaded incorrectly by the new implementation
• KT-81206 Reflection: non-substituted Function type in suspend function supertypes
• KT-81804 Reflection: remove support for multi-field value classes
• KT-81664 Reflection: IAE “argument type mismatch” on calling member extension with value class in the signature

JavaScript

New Features

• KT-83454 K/JS: Support ES6 classes in js() calls
• KT-83455 K/JS: Support ES6 default function arguments in js() calls
• KT-83453 K/JS: Support ES6 concise methods in js() calls
• KT-83457 K/JS: Support ES6 spread operators in js() calls
• KT-83456 K/JS: Support ES6 rest function parameters in js() calls
• 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-64951 Kotlin-Multiplatform does not allow JSExport of expect
• KT-83528 K/JS: Array holes in array literals are ignored in the new js() parser
• KT-84134 KJS/CMP: “IrLinkageError: Function ‘get’ can not be called: No function found for symbol”
• KT-65802 How to implement Interfaces in Javascript/Typescript?
• KT-83830 Relocate org.antlr.v4 to an internal package
• KT-83572 KJS/Wasm: Cannot access @JsModule-declared class from non-modular project
• KT-83930 Kotlin/JS: JsStatic on property of interface companion generates incorrect d.ts
• KT-70986 Add Swc into the compilation pipeline of Kotlin/JS
• KT-78742 Investigate the usage of the ANTLR-generated parser for the js function
• KT-60554 KJS: rethink JS_*_NAME_CLASH diagnostics
• KT-82552 KJS: “Non-abstract class does not implement inherited abstract member from class” errors in generated .d.ts
• 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
• KT-41082 KJS: ‘Reflection is not supported on JavaScript target, so you won’t be able to read this annotation in runtime' warning is inconvenient and misleading
• KT-82279 KJS: DCE removes external members overrides without reason
• KT-52800 KJS / IR: sealed interface with nested data classes not accessible
• 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-82263 Implement exporting top-level properties in Analysis API-based TypeScript Export
• KT-82362 KJS: Incorrect types generated in .d.ts for JsName-annotated enum entry
• KT-82262 Implement exporting top-level functions in Analysis API-based TypeScript Export
• KT-82144 K/JS: ‘meta’ identifier usage in js() inline calls prevents expression from parsing
• KT-82149 K/JS: new calls without arguments produce exceptions in js() inline calls
• KT-81730 Optimize suspend functions compilations via JS generators
• KT-79243 [JS] Drop K1-specific tests, testrunners and test directives

Klibs

New Features

• KT-83101 Implement experimental KLib ABI dump parser

Fixes

• KT-82586 Export in previous version (JS, Wasm): adjust the checker for incompatible Kotlin stdlib/compiler pairs
• KT-84273 [Klib] Added IrOffsetsChecker broke backward klib compatibility
• KT-80910 [Klib] Ensure serialized source coordinates are correct
• KT-81955 [JS] Support testing of forward compatibility with export in previous version
• KT-81957 [JS] Create a common Gradle test task
• KT-82736 False positive IR_PRIVATE_CALLABLE_REFERENCED_BY_NON_PRIVATE_INLINE_FUNCTION_ERROR on referenece to local declaration
• KT-82758 [PL] Change the behavior of getting name of removed property
• KT-81470 Simplify inline function deserialization after the bootstrap update
• KT-81466 Enable KlibAnnotationsInMetadata by default in LV 2.5
• KT-82208 K/Wasm: allow using newer stdlib with older compiler
• KT-83328 kotlin-wasm-benchmarks: Compilation errors due to missing KLIB dependencies
• 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
• KT-82213 IR linker doesn't complain when a private value class constructor is used from another module
• KT-81003 KLIBs: Eliminate excessive implicit casts in common prefix on the 1st stage
• KT-81670 K/N: Many Section still use none cacheable zip when Xklib-zip-file-accessor-cache-limit flag set
• KT-81954 [JS] All forward compatibility tests fail
• KT-81709 [KLIB Reproducibility] KLIB zip file generation is non-deterministic due to unsorted file system traversal
• KT-81474 [Tests][Klibs] Migrate Klib evolution tests to PL tests engine

Language Design

• KT-83009 Exposing of non-exportable API from interfaces
• KT-73502 Context parameters: it is not possible to declare local function with a context

Libraries

New Features

• KT-81997 Method to create a detached copy of a Map entry
• KT-79093 Expose FirResolvedStatus.hasMustUseReturnValue in kotlin-metadata

Performance Improvements

• KT-75801 Optimize Array to list conversion using array copy instead of a loop
• KT-82038 K/N: iterating over Array.asList is slower compared to ArrayList

Fixes

• KT-78115 Investigate the current situation with 22 kotlin.context standard library overloads
• KT-82363 Add assertIs to the list of ignorable functions
• KT-80666 K/N and K/Wasm: Regex: unassigned category is excluded from other chars
• KT-80665 K/N and K/Wasm: Regex: unicode category Symbol matches some punctuation marks
• KT-78089 K/N: Regex: Quantified groups matching is causing a stack overflow
• KT-82783 HashMap (K/N, Wasm), MapBuilder (all targets) duplicate keys
• KT-52400 Deprecate @BuilderInference
• KT-80786 Annotate kotlin-stdlib-jdk7/8 with @IgnorableReturnValue
• KT-83181 Remove @IgnorableReturnValue from contract DSL functions
• KT-82033 Array<Array>.flatten fails with obscure error when total length exceeds List's size limit
• KT-83290 Remove unnecessary ExperimentalTime annotation from Uuid functions
• KT-83026 Specify compareTo behavior for Boolean
• KT-82868 Restore accidentally deleted JS-specific note in ArrayList documentation
• KT-81563 Document kotlin.collections.HashMap and HashSet
• KT-81562 Document kotlin.collections.ArrayList
• KT-60535 Mark SubclassOptInRequired and RequiresOptIn with MustBeDocumented
• KT-64649 Add explanation to “A compileOnly dependency is used in the Kotlin/Native target” warning message

Native

• KT-83542 Switch the default GC back to PMCS in 2.3.20-RC
• KT-82387 Kotlin <-> Xcode compatibility issue
• KT-75806 KN Compiler with debug build can not produce executable with debug info
• KT-81828 Update exception messages regarding disabling native cache
• KT-81495 Consider making Kotlin/Native distribution compiler cache reproducible
• KT-81501 Make Kotlin/Native distribution runtime .bc and fingerprint reproducible
• KT-80790 ‘Argument list too long’ error when using dynamic_caches
• KT-48566 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
• KT-81666 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 -Xccall-mode both by default for custom cinterop klibs
• KT-81548 Native: compiler doesn't sanitize CCall.Direct symbol names in C stubs
• KT-81538 Native: InteropBridgesNameInventor doesn't handle legitimate ‘$’ characters in function names
• KT-81017 Native: compiler can't call CCall.Direct with ‘$’ in the symbol name

Native. ObjC Export

• KT-82160 K/N: bridge for fake override is not built but requested
• KT-83736 Objective-C export with objcExportBlockExplicitParameterNames generates invalid block signature when lambda parameter is named id
• 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-82635 Enable CMS GC by default in 2.3.20-Beta1
• KT-83470 Potential race condition in TryRequestThreadsSuspension due to initialization order
• KT-83549 Provide an experimental Platform property which returns information about object allocation mode
• KT-83535 Typo in out-of-memory error message
• KT-81152 Kotlin/Native: deprecate isMemoryLeakCheckerActive
• KT-81156 Kotlin/Native: deprecate forceCheckedShutdown

Native. Swift Export

New Features

• KT-82908 Swift Export: bridges for FT should be recursive

Fixes

• KT-82054 Swift Export: private set is ignored by swift export
• KT-83499 Swift Export: trampoulines w/ varargs results in a broken swift code
• KT-83655 Typealias to a closure receiving a closure results in broken swift code
• KT-82053 Swift Export: Returning generic on top level function produces uncompilable code
• KT-80971 Swift Export: Support exception throwing
• KT-83141 Swift Export: suspendable covariant functional type
• KT-82907 Swift Export: attributes are not printed for parameters of closures
• 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
• KT-81270 K/N - Build fails when exposing suspend functions

Tools. BCV

• KT-80938 Binary compatibility validation: can't exclude container types of Repeatable annotations by filters.excluded.byNames
• KT-83484 Create fat-jar artifact for abi-tools [ABI Validation]
• KT-80747 Refactor API of ABI tools [ABI Tools]

Tools. Build Tools API

New Features

• KT-80681 BTA: introduce a special argument for passing compiler plugins
• KT-80338 Kotlin CRI generation
• KT-78198 BTA: implement basic metrics collection
• KT-79975 BTA: add ability to cancel build operations
• KT-81790 [BTA] Make build operations and configuration immutable after execute
• KT-82702 BTA: Allow collecting compiler lookups in non-incremental mode
• KT-81847 Add CRI <-> BTA integration
• KT-81845 Add CRI <-> Maven integration

Fixes

• KT-84577 BTA: API 2.3.20 incompatible with compiler 2.3.10
• KT-82682 BTA: reading non-nullable arguments may return null or throw NPE
• KT-81729 BTA: loading from a classloader without implementation fails with CNFE instead of error with explanation
• KT-83971 BTA: OperationCancelledException cannot be thrown properly from isolated classloader
• KT-82167 Add BuildTimeMetric for the CRI data generation
• KT-81846 Add FUS for CRI usage in Gradle / Maven
• KT-82399 [BTA] JvmClasspathSnapshottingOperationImpl doesn't use Option defaults
• KT-82039 BuildEvent compilation error missing with KGP 2.3.0-Beta1
• 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-83044 Report redundant CLI arguments when they have no effect
• KT-83202 Report all errors during parsing CLI arguments instead of a single one
• KT-73320 Migrate the main JS CLI pipeline to the phased structure
• KT-81898 Introduce a CLI option to disable source file sorting
• 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-81551 Introduce an experimental CLI option for enabling local type aliases
• KT-74196 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-83823 Deprecate PreprocessedVirtualFileFactoryExtension
• 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

New Features

• KT-71893 Support @Builder lombok annotation on methods
• KT-28594 Add a ‘jpa’ pre-defined flavor to the allOpen compiler plugin.
• KT-81604 Lombok Kotlin compiler plugin and -Werror: Unable to ignore warning for the plugin appliance

Fixes

• KT-83119 Lombok. canEqual is not available from kotlin for a class with @Data annotation
• KT-83334 Lombok. Builder function is unavailable for a generic class
• KT-83063 Lombok: Setter/getter is not available with a protected access level
• KT-83217 Lombok. With method is available for the static field
• KT-83120 Lombok. A constructor is available for a class with an existing constructor and @Data/@Value annotation
• KT-83256 Lombok. Setter is available for non-final fields if @Value and @Data/@Setter are used together
• KT-83251 Lombok. Constructor from @Value includes fields that are initialized in declaration
• KT-83252 Lombok. Class marked with @Value isn't final
• KT-83085 Lombok: getter/setter is available for a static field if class is annotated
• KT-83078 Lombok: getter and setter are not available for a static Java field
• KT-82341 Migrate official compiler plugins to IC-safe reference... API

Tools. Compiler plugins. Compose

• KT-84218 [2.3.20-Beta1] “IllegalStateException: no implementation for FUN MISSING_DECLARATION” during bitcode lowering
• KT-84055 Reference to lambda in lambda in function ‘TextField’ can not be evaluated

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-79389 Add allopen plugin + JPA preset to kotlin.plugin.jpa
• KT-78200 Gradle: enable JVM compilation through BTA by default
• KT-81844 Add CRI <-> Gradle integration

Performance Improvements

• KT-84152 Memory Leak and OOM Errors in Kotlin Gradle Plugin 2.3.20-Beta2 with in-process execution mode

Fixes

• KT-80186 Remove usage of deprecated Gradle API Project.container(...)
• KT-78754 KGP: Remove usages of isVisible/setVisible
• KT-80356 Compatibility with Gradle 9.2.0 release
• KT-78763 Compatibility with Gradle 9.1.0 release
• KT-83316 [BTA] Build Reports missing information when JVM compilation uses Build Tools API
• KT-82885 Run tests against Gradle 9.3.0
• KT-83125 Deprecate out-of-process compilation mode
• KT-82323 Deprecate LanguageSettings.enableLanguageFeature DSL
• KT-83323 Run integration tests against Gradle 9.2
• KT-82884 Compile against Gradle API 9.3.0
• KT-78104 Deprecate CleanableStore infrastructure
• KT-80096 Strange “Inconsistent JVM Target Compatibility” warning
• KT-82715 Declaring dependencies using multi-string notation has been deprecated
• KT-83161 CRI: it is not clear that CRI generation requires BTA being enabled
• KT-82717 Specifying ‘org.gradle.java.installations.auto-detect’ as a project property on the command line has been deprecated
• KT-81830 Create autogenerated kotlin version constants to be used with disableNativeCache DSL
• KT-83322 Compile against Gradle 9.2 API
• 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
• KT-80008 Track cross compilation status from project dependencies
• KT-78764 Compile against Gradle 9.1 API

Tools. Gradle. BCV

• KT-80674 Rename tasks to avoid using legacy word [ABI Validation]
• KT-80614 Add dependency on abi check from gradle's check task [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-84772 Bundled yarn.lock for kotlinWasmToolingSetup does not include @swc/helpers@0.5.17
• KT-82946 Js, Wasm: Upgrade NPM dependencies

Tools. Gradle. Multiplatform

New Features

• KT-77258 Query status of cross-compilation or compilation task
• KT-81849 Replace kotlin-test-common and kotlin-test-annotations-common with just kotlin-test

Fixes

• KT-83917 compileCommonMainKotlinMetadata fails in CMP core repository with Kotlin 2.3.20-Beta1
• KT-82090 Kotlin JVM + Android Shared Source set fails Import with the Project Isolation enabled
• KT-81973 NPE with Cannot invoke “java.util.List.get(int)” because “path” is null in KMP + Android project
• KT-79257 Consider deprecating and removing kotlin.kmp.isolated-projects.support
• KT-81944 Legacy KMP Android uses wrong configurations to infer common dependencies
• KT-83687 Revert deprecation of ‘androidTarget’ for AGP lower than 9
• 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-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-84759 iosX64 should not be marked as deprecated in Kotlin Gradle DSL
• KT-83598 KotlinNativeDownloadTask build caching is unsafe
• KT-80715 Deprecate kotlin.native.cacheKind and introduce DSL instead
• KT-83353 DisableNativeCache breaks up-to-date checks for non-cacheable K/N targets
• KT-81443 ConfigurationCacheError on Linux arm64 due to disabled iOS targets
• KT-82970 Warning about disabled K/N caches for non-cacheable targets is printed twice
• KT-82786 Warning about disabled K/N caches is displayed twice

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

Tools. Maven

• KT-83565 Maven: auto‑detect src/main|test/kotlin
• KT-79304 Maven: Automatically add kotlin-stdlib dependency
• KT-83111 Add JavaVersion argument resolver for kotlin-maven-plugin-test
• KT-83112 Add MavenVersion argument resolver for kotlin-maven-plugin-test

Tools. REPL

• KT-82575 [K2 REPL] Redesign frontend resolution for REPL snippets
• KT-82741 [K2 Repl] OOM in FirJavaElementFinderKt.collectAllDependentSourceSessionsTo when rerunning the same cell multiple times

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-82877 Add performance measurement for KLIB size
• KT-79576 Included build subprojects produce FUS files with unknown_id when configuration cache is enabled

2.3.10

Compiler

• KT-83984 Data races around kotlinx.serialization plugin protobuf extensions registration
• KT-83317 ClassCastException: with cast kotlin.UInt to java.lang.Number when defining constant
• KT-83031 K2: unstable resolution of EnhancedNullability from type-use NotNull in presence of unused code
• KT-81700 flaky overload resolution behaviors (false-positive errors, different final candidates, compile-time failures)
• KT-83983 Revert of KT-83081
• KT-83314 JSpecify @NullMarked changes Java equals(Object) to equals(Any?) causing override conflict in Kotlin 2.3
• KT-82863 @NoInfer regression since 2.2.20
• KT-82841 “kotlin.NoWhenBranchMatchedException” in when with !is check & non-sealed class in the middle of hierarchy

JVM. Reflection

• KT-83608 Kotlin-reflect: “Unknown origin of public abstract operator fun invoke(p1: P1, p2: P2): R”
• KT-83361 “KotlinReflectionInternalError: Type parameter not found: 0” on super types with Kotlin 2.3.0
• KT-42199 “KotlinReflectionInternalError: Unknown origin of public abstract operator fun invoke” on function reference to FunctionN.invoke
• KT-81024 Reflection: New KType implementation fails on arguments comparison for a Nothing type parameter

Tools. Compiler Plugins

• KT-83266 “Unsupported class file major version 69” for “produceReleaseComposeMapping” task with Kotlin 2.3
• KT-83099 Compose compiler does not generate stack trace mappings for project files

Tools. Gradle

• KT-83070 The KGP api reference is missing a description
• KT-82459 Improve iOS simulator boot implementation

Tools. Gradle. JS

• KT-82946 Js, Wasm: Upgrade NPM dependencies

Tools. Gradle. Multiplatform

• KT-83687 Revert deprecation of ‘androidTarget’ for AGP lower than 9

2.3.0

Analysis API

• KT-80082 K2. False positive “Cannot resolve method” for self-bounded generic with wildcard return type in Java interop
• KT-80303 Move :native:analysis-api-klib-reader to :libraries:tools

Analysis API. Code Compilation

• KT-70860 K2 IDE / Kotlin Debugger: CCE “java.lang.String cannot be cast to java.lang.Void” on evaluating not-null variable on the line with assigning null to that var
• KT-78554 K2 IDE / Kotlin Debugger: ISE “No override for FUN IR_EXTERNAL_DECLARATION_STUB” on calling toString() for local class instance during evaluation
• KT-73201 K2 IDE: Error while evaluating expressions with local classes

Analysis API. FIR

• KT-81378 Expected expression ‘FirFunctionCallImpl’ to be resolved caused by suspend {}
• KT-80473 Add events for tracking LL activities
• KT-46375 Analysis API: Support cross-file class redeclaration checks using indices
• KT-80471 Analysis API: Deduplicate equivalent call candidates in resolveToCallCandidates
• KT-79653 [Analysis API] ContextCollector: BODY context of enum classes doesn't contain enum entries
• KT-75858 K2 AA: False positive ‘property must be initialized’ on incremental analysis with ‘field’ usage and semicolon in setter
• KT-80231 AnnotationArgumentsStateKeepers doesn't restore the initial annotation in some cases
• KT-80233 Pull mutation out of AnnotationArgumentsStateKeepers
• KT-71466 LLFirBuiltinsSessionFactory uses createCompositeSymbolProvider
• KT-76432 JavaClassUseSiteMemberScope: Expected FirResolvedTypeRef with ConeKotlinType but was FirUserTypeRefImpl

Analysis API. Infrastructure

• KT-80717 Support IntelliJ Bazel build in the Kotlin Coop development mode

Analysis API. Light Classes

• KT-80656 Duplicate no-args constructor in PSI
• KT-60490 Symbol Light Classes: Property accessors from a delegated interface don't present in the delegating class
• KT-79689 SymbolLightClassForClassLike.toString() causes PSI tree loading
• KT-80690 Private interface functions are not present in light classes
• KT-80256 K2: Certain actions in JPA code causes infinite PIEAE: “Element class CompositeElement of type REFERENCE_EXPRESSION (class KtNameReferenceExpressionElementType)”
• KT-79012 Add a high-level overview of light classes

Analysis API. Providers and Caches

Fixes

• KT-81476 Analysis API: AlreadyDisposedException from low-memory cache cleanup
• KT-80911 Analysis API: Execute session invalidation in a non-cancelable section
• KT-81242 Analysis API: Add UUID/lifetime properties to LL FIR session structure logging
• KT-80622 Analysis API: Visualise LL FIR session structure & weight
• KT-80904 Analysis API: “Invalid dangling file module” exception during session invalidation
• KT-78882 K2 AA: Calling containingSymbol on getProgressionLastElement causes exception
• KT-58325 Analysis API: Combine LLKotlinStubBasedLibrarySymbolProviders in session dependencies (optimization)
• KT-77825 Analysis API: CheckersComponent consumes a lot of memory while being unused in LL FIR sessions
• KT-76526 Incorrect built-in module is provided for non-JVM sources in Standalone
• KT-62549 Analysis API: Cache callables in combined Kotlin symbol providers
• KT-70721 LL FIR: investigate possibility of moving LLFirFirClassByPsiClassProvider . getClassByPsiClass (PsiClass) to symbol providers
• KT-72998 Analysis API: Introduce getClassLikeSymbolByPsi to LL FIR symbol providers

Analysis API. Standalone

• KT-81108 AA: java.lang.ClassCastException: class org.jetbrains.kotlin.fir.FirBinaryDependenciesModuleData cannot be cast to class org.jetbrains.kotlin.analysis.low.level.api.fir.projectStructure.LLFirModuleData
• KT-80573 Potential performance issue on class ID computation
• KT-80559 Try to optimize KotlinStandaloneDeclarationProviderFactory startup for tests
• KT-71706 Analysis API Standalone: StandaloneProjectFactory.createSearchScopeByLibraryRoots creates inefficient file-based search scopes

Analysis API. Stubs and Decompilation

Performance Improvements

• KT-77097 Support ReplaceWith deprecation annotation argument via stubs

Fixes

• KT-80350 Drop K1 decompiler
• KT-77082 StackOverflowError in CreateFreshTypeVariableSubstitutorStage.shouldBeFlexible
• KT-80798 Improve stubs tests coverage
• KT-75318 Read context parameter fields from metadata in CallableClsStubBuilder
• KT-77874 AA disagrees with the compiler on descriptions of context parameters from binaries in messages for context argument ambiguity errors
• KT-80276 Implement native coping for stubs
• KT-79780 Decompiled MultifileClass has Facade kind
• KT-79398 isClsStubCompiledToJvmDefaultImplementation flag is inconsistent for compiled and decompiled stubs
• KT-79798 Prettify stub usages in LL stub-based deserializer
• KT-78949 AbstractLLStubBasedResolutionTest: tests against real stub-based files
• KT-80251 Inconsistent decompiled and compiled stub for properties with an initializer and a delegate
• KT-74547 Implement decompiler for K2
• KT-79555 Move KotlinFileStubImpl serialization/deserialization to the Analysis API
• KT-79487 “null DefinitelyNotNullType for ‘T’” from decompiler
• KT-60764 Stub Builder: fix differences between K1 and K2 stub building on decompiled files
• KT-79484 An empty enum class with a member decompiles with a synthetic error
• KT-79730 Decompiled files have an extra Kt suffix
• KT-79483 data modifier is not present on object modifier
• KT-75398 Local classes from scripts have ClassId in stubs
• KT-79412 Context parameters with type annotations cause inconsistency errors while building stubs

Analysis API. Surface

New Features

• KT-80084 Provide endpoints for Analysis API to understand when the context sensitive resolution is used
• KT-64340 Analysis API: no way to get a type of vararg parameter
• KT-68387 AA: provide context for type approximations

Performance Improvements

• KT-80713 Optimize KaDeclarationSymbol#visibility for class-like symbols
• KT-79097 KaFirNamedFunctionSymbol#isSuspend shouldn't trigger resolution
• KT-79095 isOverride shouldn't trigger resolution if not compiler plugins present

Fixes

• KT-80234 Incorrect value of isActual for the implicitly actual constructor of annotation class
• KT-81132 Use KaSession instead of a particular KaSessionComponent for context parameter bridges
• KT-81129 K2: KaSymbolInformationProvider#importableFqName: should return null for dynamic declarations
• KT-81128 K2: KaSymbolInformationProvider#importableFqName: should return null for error destructuring declarations
• KT-81127 K2: KaSymbolInformationProvider#importableFqName: should return null for anonymous functions
• KT-81126 K2: KaSymbolInformationProvider#importableFqName: should return null for enum entry initializer constructors
• KT-81125 K2: KaSymbolInformationProvider#importableFqName: should return null for property accessors
• KT-81124 K2: KaSymbolInformationProvider#importableFqName: type alias constructor should have a reference to the type alias and not to the underlying class
• KT-70127 Analysis API: ‘KaFirReceiverParameterSymbol’ does not implement ‘KaFirSymbol’; leads to exception from importableFqName
• KT-81123 Reimplement KaFirSymbolInformationProvider#importableFqName
• KT-81122 Drop KaImportOptimizer
• KT-78093 Add bridges for context parameters
• KT-79772 Migrate from ‘validityAsserted’ to ‘withValidityAssertion’
• KT-79328 K2 AA, isUsedAsExpression: Unhandled Non-KtExpression parent of KtExpression: class org.jetbrains.kotlin.psi.KtImportDirective
• KT-80366 IllegalStateException from KaFirStopWorldCacheCleaner
• KT-80274 Merge AbstractMultiModuleSymbolByPsiTest to AbstractSymbolByPsiTest
• KT-80352 KaBaseResolutionScope.contains(PsiElement) always returns false for Android light classes (e.g. synthetic R.java classes)
• KT-80178 Incorrect modality for an abstract interface function with a redundant open modifier
• KT-79129 [Analysis API] KaFe10TypeCreator.buildClassType cannot build builtin types by class ids
• KT-79143 AA: argumentMapping contains an expression that is not an argument
• KT-59857 KaExpressionTypeProvider#returnType shouldn't throw an exception for class like declarations
• KT-79667 Enable resolve on java record components in standalone mode
• KT-73050 KaFirSymbolRelationProvider#expectsForActual: suspicius logic for KaReceiverParameterSymbol
• KT-78904 KaBaseWriteActionStartedChecker throws when no additional WA was done
• KT-79281 Add KDoc to KaTypePointer#restore
• KT-78597 KaUseSiteVisibilityChecker returns false for internal functions exposed via implicit receiver
• KT-71705 FIR api impl: Postfix increment expression's expressionType is Unit when incrementing array element
• KT-75057 Analysis API: Reference to object through typealias in invoke operator call leads to original type

Backend. Native. Debug

• KT-79848 Flaky debugger tests in opt.debug/cache.*/GC.CMS/GC.sch.ad/alloc.custom configuration

Backend. Wasm

New Features

• KT-59032 Support instantiation of annotation classes on WASM

Fixes

• KT-76204 K/Wasm: support generating a wasm module per kotlin module/klib
• KT-79357 K/Wasm: store data for string literals in utf8 for Latin1
• KT-82075 K/Wasm: kotlin.wasm.internal.getSimpleName crashes on iOS Safari older than 26
• KT-79244 [Wasm] Drop K1-specific tests, testrunners and test directives
• KT-69621 K/Wasm: Consider enabling support for KClass.qualifiedName by default
• KT-80397 K/Wasm: turn on by default using a new version of the exception handling proposal for wasm-wasi target
• KT-81372 K/Wasm: JsException: Exception was thrown while running JavaScript code on Safari 18.2/18.3
• KT-80018 K/Wasm: exceptions don't work properly in JavaScriptCore (vm inside Safari, WebKit)
• KT-66072 K/Wasm: improve how exceptions work in JS interop
• KT-80106 devServer in Kotlin/Wasm overwrites defaults, causing missing static paths
• KT-80210 Wasm: “Unexpected non-external class: kotlin.Nothing” caused by JsExport with JsPromise
• KT-80555 WASM IC: Can't link symbol on kotlinx.coroutines on fresh master
• KT-80415 WasmJs Number Elvis Operator Crash
• KT-76509 WasmJS: ReferenceError: Temporal is not defined caused by “Redundant reference to unused external results”
• KT-79317 [Wasm] Do not throw CCE for ExcludedFromCodegen declarations
• KT-78036 K/Wasm: generate a message with “expected” and “actual” types in case of CCE

Compiler

New Features

• KT-80461 K2: false positive NO_ELSE_IN_WHEN for complex sealed hierarchy
• KT-77676 K/N: enable typechecks and the casts optimization pass in debug mode by default
• KT-79185 Support local type aliases
• KT-80837 Warn about extension function with a context shadowed by member
• KT-80768 Warning on overloading by a superset of context parameters in class context
• KT-80031 Check spotbugs‘s @CheckReturnValue in Kotlin’s unused return value checker
• KT-79380 Native: add performance measurement for the rest of backend phases
• KT-79381 Native: add performance measurement of LLVM phases
• KT-80222 Implement the prohibition of always-false is checks for definitely incompatible types
• KT-79295 Parse and build raw FIR from new short and full forms of positional destructuring with square brackets
• KT-74810 Support typealiased/mapped Java types in unused return value checker
• KT-71244 Incorporate existing @CheckReturnValue annotation(s) into Kotlin's unused return value checker
• KT-79922 Record ‘MustUse/ExplicitlyIgnorable’ state for overrides even in disabled RVC mode
• KT-79920 Store ‘Explicitly ignorable’ state of function/property in the metadata
• KT-79690 Implement a USELESS_ELVIS_LEFT_IS_NULL with elvis expression
• KT-79296 Implement/adapt diagnostics for new destructuring
• KT-79298 Report errors on new destructuring syntax in K1

Performance Improvements

• KT-81617 Native: casts optimizations pass explodes on deep nested loops
• KT-80554 Kotlin/Native: investigate performance hit from always-on llvm pass profiling
• KT-81340 K/N: severe compilation time degradation after turning on casts optimization pass
• KT-80370 Add NO_INLINE attribute to some of runtime functions
• KT-80167 K/N: condense the nodes and edges in DevirtualizationAnalysis constraint graph
• KT-79535 Revert incorrect SAM conversion enhancements brought to K2

Fixes

• KT-79979 K2: ClassCastException when overriding extension property with delegation
• KT-82590 ClassCastException when instantiating class with generics implemented by fun interface and lambda
• KT-78881 K2: False positive “Assigned value is never read” in composable function
• KT-79276 Dexing fails with “Cannot read field X because is null” with 2.2.0
• KT-79547 “UnsupportedOperationException: Not supported” with inlining and value classes
• KT-79442 “Multiple annotations of type kotlin.coroutines.jvm.internal.DebugMetadata”: 2.2.0-Beta1 generates broken code with JVM default suspend methods in interfaces
• KT-80744 Kotlin failure on lambda with type parameter
• KT-81618 “Number of arguments should not be less than number of parameters” on JVM on Kotlin 2.3.0-Beta1
• KT-82869 Green-to-Red change in 2.3 after prioritizing non-suspend-function-type overloads
• KT-79611 “IllegalStateException: couldn't find inline method”: Exception during incremental compilation
• KT-78895 Consider dropping isLocalInFunction and FirClassLikeDeclaration.isLocal
• KT-82040 Native: ClassCastException: PointerInputChange
• KT-81924 K2: “Cannot infer type for this parameter”, “Overload resolution ambiguity between candidates”
• KT-80864 K2: Missing Val cannot be reassigned diagnostic for Java final fields (crashes in runtime with IllegalAccessError)
• KT-71420 Report error when reified type parameter is inferred to intersection type
• KT-79451 Rework approach to recursive types approximation
• KT-78413 Kotlin Debugger: value classes as context parameters have incorrect names in Variables View during debugging
• KT-82138 Debugger: Cannot evaluate JvmInline value class parameter
• KT-82381 ArrayIndexOutOfBoundsException while FirDiagnosticsCompilerResultsReporter tries to print code as part of a warning log
• KT-81068 Corrupted Unicode paths passed or used in the compiler
• KT-79783 KDoc parser: Links aren't rendered if the line has an indent of 4 or more
• KT-80549 Call of Java method with type parameter bounds: Expected FirResolvedTypeRef with ConeKotlinType but was FirJavaTypeRef
• KT-82132 False-positive type mismatch with -language-version 2.2
• KT-81988 K2: Any?.toString() causes NPE inside lambda with Java
• KT-81652 Native: ClassCastException: ApplicationForegroundStateListener.Companion
• KT-76479 Backend. JVM: Report errors on exposure of types in inline functions
• KT-82022 K/N: Unexpected “Annotation @JvmInline is missing on actual declaration” warning with value classes
• KT-80250 ISE: flow for PostponedLambdaExitNode not initialized - traversing nodes in wrong order?
• KT-76344 Drop language version 1.9 for non-JVM platforms
• KT-76343 Drop language version 1.8
• KT-80330 K2: NPE at org.jetbrains.kotlin.fir.resolve.calls.FirCallResolver.createResolvedNamedReference
• KT-80400 K2: AbstractMethodError on fun interface implementation inheriting from an interface compiled with -jvm-default=disable
• KT-9111 Improve diagnostic for call with access to outer class from nested class
• KT-78280 Implement the sourceless KtDiagnostics
• KT-74999 K2: KotlinNothingValueException within Extension Function
• KT-81254 “AssertionError: There should be at least one non-stub type to compute common supertype”: Parser issue during generic type inference
• KT-53237 NI: Frontend ignores generic bound when inferring types
• KT-81186 Only allow local type aliases in REPL/scripts until full stabilization
• KT-80929 IC Native: Undefined symbols on ktor
• KT-81657 K2: put warning about “exposing package-private in internal” under experimental language feature
• KT-81241 Konanc exit while lowering org.jetbrains.kotlin.ir.util.IrUtilsKt.remapTypeParameters
• KT-74819 K2: False-positive overload resolution ambiguity for flatMap inside PCLA
• KT-81547 Stabilize DFA-based exhaustiveness
• KT-79274 Frontend implementation of name-based destructuring
• KT-79506 Contract for getter and setter doesn't work if a property is called from another module
• KT-58988 K2: Deprecate exposing package-private parameter of internal method
• KT-80711 IC Native: NPE during link on ktor
• KT-77727 Move some of the extra checkers to the default list
• KT-76136 Switch latest stable version in Kotlin project to 2.3
• KT-81257 Native: “Unexpected boolean predicate” when generating ‘static_cache’
• KT-81525 Report REDUNDANT_SPREAD_OPERATOR on (*) instead of argument expression
• KT-81522 Fix Light Tree SPREAD_OPERATOR diagnostic positioning
• KT-77008 K2: Incorrectly force casting to a wrong type
• KT-78127 K2: Too precise inference for if/when with expected type in assignment
• KT-80208 K2: ClassCastException: “class java.util.ArrayList cannot be cast to class java.lang.Void” type inference picks Void for generic function
• KT-75797 Native: find a way to handle generates C bridges in inline functions
• KT-78819 K2: False positive ABSTRACT_MEMBER_NOT_IMPLEMENTED in KJK hierarchy
• KT-80003 Kotlin/Native: deprecate eager GlobalData initialization
• KT-79231 Inconsistent InnerClass entry flags for abstract inner enum
• KT-20677 Improve diagnostic about implicit default constructor absence for expected annotation class
• KT-81385 Missing error of nullable expression in class literal in case of reified type parameter
• KT-81251 Smartcast doesn't work for an effectively private inline function
• KT-81245 Automatic smart cast on properties with EBF is allowed on inlined property accessors
• KT-81222 Custom getter is allowed on a property with redundant EBF
• KT-80795 Wrong type cast is added for IMPLICIT_COERCION_TO_UNIT
• KT-81141 Fix FirUnsupportedArrayLiteralChecker to forbid array literals inside non-annotation contexts
• KT-81383 Return type of anonymous function used as run argument is incorrectly inferred to Nothing
• KT-80577 “Return type mismatch” for self-referential types used as generic parameters
• KT-75215 KDoc: references from @param tag are rendered as plain text
• KT-79887 K2 Compiler Internal Error in ‘FirFakeOverrideGenerator.checkStatusIsResolved’ Method
• KT-78125 false-negative shadowed contextual overload warning on local declarations
• KT-81198 Move type and type parameter annotations from jvm_metadata.proto to metadata.proto
• KT-81057 Wrong handling of boxing during redundant casts optimization
• KT-81191 K2: “null cannot be cast to non-null type ConeTypeParameterLookupTag” with invalid code
• KT-80285 IJ monorepo: broken compilation after 2.2.20-RC update
• KT-81115 Allow converting lambda with explicit parameter when assigning to variable of an extension function type
• KT-74588 Redundant checkNotNull intrinsics instructions for Java generic methods
• KT-78390 Unmute FusStatisticsIT.testKotlinxPlugins() after AtomicFU updates kotlin-metadata-jvm
• KT-79369 Forbid typealiasing for all compiler-required annotations
• KT-69294 K2: Report CONSTRUCTOR_OR_SUPERTYPE_ON_TYPEALIAS_WITH_TYPE_PROJECTION_ERROR instead of EXPANDED_TYPE_CANNOT_BE_INHERITED after switching to LV 2.2
• KT-81064 Wrong safe call null check handling during redundant casts optimization
• KT-80871 StackOverflowError on AnnotationTarget.TYPE
• KT-80908 K2: Compiling type annotation with self-annotated vararg fail with exception
• KT-81018 ISE “IR class for Foo not found” on missing dependency when lowering SAM constructor
• KT-80936 NON_PUBLIC_CALL_FROM_PUBLIC_INLINE : @PublishedApi doesn't work for fun interfaces
• KT-75748 StackOverflowError when reading array from metadata annotations
• KT-80606 KotlinIllegalArgumentExceptionWithAttachments when using property itself in explicit backing field initialization
• KT-80940 K2: Exception in FIR2IR with AnnotationTarget.TYPE with self-annotated non-vararg default argument and usage in child module
• KT-80538 KaFirDiagnostic.EmptyRange doesn't work in most of the cases
• KT-80524 Class is not abstract and does not implement abstract member when compiling with kotlinc-jklib
• KT-80597 Apply fix for CVE-2024-7254 to our fork of protobuf 2.6.1
• KT-80849 K2: ConstValueProviderImpl doesn't distinguish files with same name and package
• KT-80602 Exhaustiveness checker improvements for 2.3
• KT-80735 Support || return/throw shortcut in unsed return value checker
• KT-79651 Report a warning about an unused return value only on the function name
• KT-80719 False positive: “Redundant visibility modifier”: when overriding protected methods as “public”
• KT-80434 K2: DSL marker doesn't work with lambda fields
• KT-80383 Getter without a body is allowed on a property with an explicit backing field
• KT-80446 Explicit visibility modifiers are allowed on EBF
• KT-80378 ClassCastException on callable reference to a property with EBF
• KT-80377 Fir2Ir: “Cannot determine expected receiver type” for callable reference to a property with EBF outside of class
• KT-80455 K2: StackOverflowError in when exhaustiveness checker on red code
• KT-72862 [Native caches] Umbrella for failing codegen/box tests for corner cases in synthetic accessors
• KT-20278 NO_TYPE_ARGUMENTS_ON_RHS: Confusing diagnostic for inner class of generic outer class
• KT-80418 Property with EBF with functional type isn't resolved if its type is Any
• KT-80469 Functional type from property is always used for explicit backing field
• KT-80535 Missing INITIALIZER_TYPE_MISMATCH for EBF
• KT-80445 Private visibility is possible for a property with EBF
• KT-80164 Move name generation for unnamed context parameters to frontend
• KT-80684 Line breaks are lost in multi-line diagnostic messages since 2.3.0
• KT-78112 RETURN_VALUE_NOT_USED is reported for local function even if it isn't marked with annotation in CHECKER mode
• KT-48311 Incorrect LINENUMBER after if with a suspend call
• KT-80688 Bad SourceDebugExtension caused by enhanced coroutines debugging
• KT-73851 Native: compilation fails with ClassCastException with genericSafeCasts=true
• KT-77593 Add a warning when @IgnorableReturnValue is inconsistent between expect/actual functions
• KT-79386 Confusing error message when named parameters are used for java method calls
• KT-80600 K2: Private and final modifiers are allowed on setter of open delegated property
• KT-77101 Invoke on callable reference is considered ignorable
• KT-79923 Remove lookup of @IgnorableReturnValue annotation from FirReturnValueOverrideChecker
• KT-80517 Synthetic kotlin.Any members in data classes are missing @MustUseReturnValue
• KT-80194 VAR_TYPE_MISMATCH_ON_OVERRIDE: doesn't mention the inferred type
• KT-80484 K2: ClassCastException due to fake source for implicit lambda parameter (RedundantNullableChecker)
• KT-80592 UninitializedPropertyAccessException when anayzing annotations on members of anonymous classes
• KT-80399 Anonymous Kotlin class incorrectly warns about deprecated java override despite ‘@Deprecated’ annotation
• KT-79610 Adding CocoaPod to Kotlin/Native MPP triggers IR serialization failure and commonizer errors
• KT-79951 Infinite loop in parsing incomplete full form destructuring
• KT-79866 kotlinc 2.2.0 silently emits ‘NonExistentClass’ instead of reporting an error
• KT-79777 Argument type mismatch on value of complex type with a captured raw type argument
• KT-78664 False positive VARIABLE_NEVER_READ and ASSIGNED_VALUE_IS_NEVER_READ on function type variable with splited declaration and assignment
• KT-79496 False positive “when must be exhaustive” in triangle interface/class hierarchy
• KT-79774 KtDestructuringDeclaration.getLPar & getRPar are broken
• KT-80391 K2: Only one context parameter is mentioned in the [NO_CONTEXT_ARGUMENT] diagnostic
• KT-79785 ktypew:kotlin.collections.List already exists error using Swift Export
• KT-78879 “Sealed types cannot be instantiated”: Can't instantiate Java-defined sealed Class from Kotlin
• KT-21598 Extension is shadowed by member should not be reported when member is deprecated with HIDDEN level
• KT-79622 FUNCTION_EXPECTED: Misleading ‘expression cannot be invoked as a function’ when inaccessible with private lambda
• KT-80255 [EXTENSION_FUNCTION_IN_EXTERNAL_DECLARATION] can be attached to the receiver type of a functional type
• KT-79816 Java Interfaces implemented by delegation have non-null return checks
• KT-80177 Improve message of RECEIVER_SHADOWED_BY_CONTEXT_PARAMETER in case of member extension
• KT-79770 There is no RECEIVER_SHADOWED_BY_CONTEXT_PARAMETER if the usage of fun is from inside the class
• KT-79430 False positive EXTENSION_SHADOWED_BY_MEMBER on overridden member extension
• KT-62934 Incorrect line mapping inside inline lambda after non-local return
• KT-79545 K2: no error on crossinline lambda usage in anonymous object base constructor call
• KT-79643 HAS_NEXT_FUNCTION_AMBIGUITY and NEXT_AMBIGUITY diagnostics are always ignored in favor of HAS_NEXT_FUNCTION_NONE_APPLICABLE and NEXT_NONE_APPLICABLE
• KT-79327 Modifier ‘private’ is not applicable to ‘value parameter’ is reported for context parameters
• KT-76453 K2 IDE: autocomplete freeze
• KT-77182 A function in a file annotated with @file:MustUseReturnValue doesn't produce a warning when it is used from compiled code
• KT-78541 Jspecify: Unsound platform type despite @NullMarked for an override with a generic-subclass return type
• KT-79672 ‘when expression must be exhaustive’ even after using ‘require()’
• KT-71306 K2 IDE / Kotlin Debugger: “Cannot find local variable ‘block’ with type kotlin.jvm.functions.Function0” on evaluating lambda arg inside inline function
• KT-76991 K2 IDE / Kotlin Debugger: ISE “Couldn't find declaration file for” on evaluating local fun when the scope has also inline fun from another file call
• KT-79877 K2 IDE / Kotlin Debugger: failed evaluations of a code fragment capturing local data class
• KT-77401 [FIR] ParameterNameTypeAttribute.name doesn't support @ParameterName with compile-time constant property argument
• KT-79682 Fix partially uninitialized locals after coroutine spills insertion
• KT-79562 NPE when passing non-lambda argument of nullable non-suspend function type into function that accepts nullable suspend function type
• KT-79693 NotImplementedError: An operation is not implemented: Unknown file with KMP separate compilation
• KT-79662 Unused return value checker doesn't work for com.google.errorprone.annotations.CheckReturnValue
• KT-79781 Missing MISSING_DEPENDENCY_CLASS when using type alias with inaccessible RHS
• KT-77772 Only report exposed type on qualifier if it's resolved to an object
• KT-79765 K2. Do not report ignore return value for unresolved reference
• KT-79017 False negative REDECLARATION on private nested class
• KT-79519 Nested type alias is unreachable from another module
• KT-72039 StackOverflowError on calling keySet on a Kotlin subclass of Java subclass of ConcurrentHashMap
• KT-75843 K2: incorrect line numbers in an if-expression with a super-call
• KT-77504 Add a warning when @IgnorableReturnValue is inconsistent on overrides
• KT-78389 Perform version 2.3 boostrapping
• KT-79092 Crash on default argument in function in fun interface
• KT-77729 Package-level @NullMarked does not work when kotlinc sees .java source files
• KT-79013 False negative NOT_YET_SUPPORTED_IN_INLINE on inline local functions inside inline functions
• KT-79139 False positive CONFLICTING_OVERLOADS for context parameters instead of receivers
• KT-35305 Address the overload conflict resolution between unsigned and non-primitive types
• KT-42096 No diagnostic reported on inline modifier on an enum entry
• KT-79355 Failed to fix the problem of desugared inc with new reverse implies returns contract
• KT-79277 Implies returns contract doesn't affect the return type of the function if it is in the argument position
• KT-79271 Implies returns contract doesn't impact exhaustiveness
• KT-79218 SMARTCAST_IMPOSSIBLE for top‑level extension‑property getter despite returnsNotNull contract
• KT-79220 returnsNotNull contract ignored on extension function with nullable receiver
• KT-79354 IllegalStateException: Debug metadata version mismatch. Expected: 1, got 2 with compiler 2.2.20-Beta1 and stdlib 2.2.0
• KT-77986 K2: False negative: “Local classes are not yet supported in inline functions”
• KT-79456 Redeclaration conflict checks of private top-level classifiers rely on an incorrect containing file
• KT-79125 RVC full mode: delegated interfaces are not checked
• KT-63720 Coroutine debugger: do not optimise out local variables
• KT-78595 type variable leak on a generic property as a call argument given an unstable smart cast
• KT-79076 ‘IllegalStateException: Cannot serialize error type: ERROR CLASS: Uninferred type’ with Exposed column using recursive generic type
• KT-59807 K2: Replicate the MUST_BE_LATEINIT logic from K1
• KT-76782 K2: Incorrect resolve into unrelated invoke operator with wrong diagnostic
• KT-78066 TYPE_PARAMETER_OF_PROPERTY_NOT_USED_IN_RECEIVER error message does not account for context parameters
• KT-76065 Drop JavaTypeParameterDefaultRepresentationWithDNN feature
• KT-77808 Inference: recheck the code about DNN-related hacks
• KT-24202 NOTHING_TO_OVERRIDE if super-class reference misses generic arguments
• KT-78909 K2: Missing diagnostics [CYCLIC_INHERITANCE_HIERARCHY] for recursive class inheritance leads to StackOverflowError
• KT-75969 java.lang.IllegalArgumentException: source must not be null on red code
• KT-76902 Omit type-use annotations from diagnostics
• KT-17460 Diagnostics and intention on suspend function that is overriden with non-suspend one.
• KT-56665 K2: false positive RECURSIVE_TYPEALIAS_EXPANSION
• KT-78932 Contracts are allowed for open and overridden property accessors
• KT-77203 FIR: Consider adding destructured type to all COMPONENT_FUNCTION_* diagnostics
• KT-77685 “IllegalArgumentException: Sequence contains more than one matching element”
• KT-78452 Drop redundant frontend structures after fir2ir conversion
• KT-70507 Should parentheses prevent from plus/set operator desugaring?

Compose compiler

New features

• 98d3907 Introduce a compose group analysis module that produces a proguard/R8 mapping from group keys in bytecode.

Fixes

• b/419049140 Disabled memoization in try blocks
• KT-81081 Generate Compose-specific proguard mappings when Compose compiler plugin is applied.
• b/431025881 [Compose] Clean up runtime version checker
• b/365922168 Add java.util.Locale to the list of known stable classes
• b/407549020 Introduce a registry of known stable markers
• b/417989445 Added a diagnostic to restrict usages of runCatching in @Composable functions
• KT-80294 Fix crash with inline @Composable function reference
• b/430140896 Fix IrSourcePrinter output for when branch check and typechecks
• CMP-9167 iOS: Platform declaration clash: The following functions have the same IR signature

IDE. Gradle Integration

• KT-46273 MPP: Don't fail import for case of missed platform in source set structure
• KT-46417 [UNRESOLVED_REFERENCE] For project to project dependencies of native platform test source sets
• KT-44845 After update to Kotlin 1.4.30 all external dependencies is unresolved in IDE with kotlin.mpp.enableGranularSourceSetsMetadata=true
• KT-46142 K/N distribution is unavailable from IDE with multiplatform hierarchical project structure enabled

IR. Actualizer

• KT-77337 IrNoExpectSymbolsHandler finds expect class reference after enabling annotation traversal in IR
• KT-80002 Investigate the need for map copying in IrCommonToPlatformDependencyExtractor.kt
• KT-80131 KMP Separate Compilation: No override for FUN IR_EXTERNAL_DECLARATION_STUB name:
• KT-80064 KMP Separate Compilation: ClassCastException: class org.jetbrains.kotlin.ir.symbols.impl.IrTypeAliasSymbolImpl cannot be cast to class org.jetbrains.kotlin.ir.symbols.IrClassSymbol
• KT-80051 KMP Separate Compilation: Actualization of common dependencies failed on ‘PROPERTY FAKE_OVERRIDE name:modCount visibility:protected modality:FINAL [fake_override,var]’
• KT-79998 KMP Separate Compilation: java.lang.IllegalStateException: No override for FUN IR_EXTERNAL_DECLARATION_STUB name:

IR. Inlining

New Features

• KT-70360 KLIBs: Uniformly handletypeOf() calls at 1st/2nd stages of compilation

Performance Improvements

• KT-69497 Crossinline lambda is allocated on K/N & JS

Fixes

• KT-78673 Make fakeOverrideLocalGenericBase not using red code
• KT-78537 [Inliner] Incorrect KFunction.name of a reference to inlined local function
• KT-74892 Investigate passing inline lambda as argument of another inline function
• KT-81673 False warnings about ABI change in dependencies in library mode in 2.3.0-Beta1
• KT-81713 [Inliner] Compilation of inline function with recursive call applied to TODO() fails with an internal error
• KT-80653 [IR Inliner] Space: “Local declarations should've been popped out by this point”
• KT-78392 CommonPrefix: Add a way of stopping execution when one of the phases is unsuccessful
• KT-80927 [Native] Review intrinsics with PublishedApi
• KT-81070 [Inliner] kotlin/Any is unbound
• KT-80628 KLIB inliner: Not enough information about the “full” mode
• KT-69516 Double-inlining for Native: Enable visibility checks after 1st phase of inlining
• KT-79334 Unify intrinsics used on 1st phase of IR inliner in KLIB-based compilers
• KT-80610 KLIB inliner: Always apply cross-module inlining to pre-processed inline functions
• KT-80565 KLIB Inliner: Add a special annotation to prohibit inlining of marked inline functions in stdlib on 1st compilation phase
• KT-80883 [Inliner] Run pre-serialization lowerings in all testrunners
• KT-77876 IrVisibilityChecker: Different set of exceptions for 1st and 2nd compilation stages
• KT-80693 [IC] Split IC invalidation tests for cross-module IR Inliner
• KT-79718 KLIB inliner: Emit warning on generation of public synthetic accessor when running in “explicit API mode”
• KT-80226 [IR Inliner] Generate constructor accessors as constructors, not static functions
• KT-80692 [IC] Split IC invalidation tests for intra-module IR Inliner
• KT-77103 [Inliner] IrLocalDelegatedProperty was not serialized, while its symbol and IrRichPropertyReference were.
• KT-80537 The expected error is not emitted from FirJsKlibSyntheticAccessorsTestGenerated and NativeKlibSyntheticAccessorsTestGenerated
• KT-78903 Unify codegen/boxInline tests with codegen/box
• KT-78989 Add missing PL tests for inline functions/property accessors
• KT-79771 kotlinx-coroutines-core: Public synthetic accessor generated with enabled KLIB IR inliner
• KT-79680 IrConstructorSymbolImpl is unbound in lambdaWithoutNonLocalControlflow.kt
• KT-70849 Ensure correct debug info for intra-module IR inlining on the first compilation phase
• KT-79800 JS BE errors with default values when IR inliner is enabled
• KT-79352 Remove excessive validations from ValidateAfterAll... on the first stage
• KT-76599 Migrate IrValidationAfterInliningAllFunctionsPhase to the first stage of compilation
• KT-78245 Synthetic Accessors incorrectly copies default values
• KT-72594 [JS][Native] Add IrInliningFacade to test runners

IR. Interpreter

• KT-72356 K2 Native: IllegalStateException when annotation has the same source range as a constant in another file
• KT-72881 K2: incorrect empty array as annotation argument when parameter has default value

IR. Tree

Fixes

• KT-79371 Fix handling of broken SAM conversion in PL with enabled Rich References
• KT-81952 “IllegalStateException: Callable reference with vararg should not appear at this stage” for callable references to functions with generic vararg parameters
• KT-79739 Static synthetic accessors inside generic classes access its type parameters
• KT-78100 Track and annotate internal annotations with @PublishedApi to enable annotation visibility validation
• KT-80825 Drop IrSerializationSettings.reuseExistingSignaturesForSymbols setting
• KT-79807 Broken IR tree invariants in IrReplSnippet after FIR2IR
• KT-77819 [IR] Fine-tune IrValidator's run after Fir2IR and IR plugins
• KT-70160 Remove IrDeclaration.parents after Anvil update
• KT-80454 LocalDeclarationsLowering: Clean-up the dead code
• KT-80819 Rework IrFileValidator to use Hashmap instead of ClassValue
• KT-80516 Kotlin-like IR dump: Don't render tailrec as lateinit
• KT-78856 Refactor LocalDeclarationsLowering to split it in smaller parts
• KT-79439 KLIB stdlib symbols loading: Split the result of merging of IrBuiltins with BuiltinSymbolsBase hierarchy into two parts (for 1st & 2nd phases)
• KT-79437 KLIB stdlib symbols loading: Drop loading functions from IrBuiltins and migrate usages to SymbolFinder functions and lazy filtering
• KT-79569 Unexpected error during DFG phase in Native due to PL issue with SAM conversion represented by rich reference
• KT-76601 IrValidatorConfig should have all checks disabled by default
• KT-69662 Deduplicate function createTemporaryVariable
• KT-79440 KLIB stdlib symbols loading: Drop BuiltinSymbolsBase from plugin API
• KT-78960 [FO] Limit static fake overrides generation for static functions
• KT-76813 IR validator: not all symbols/references are visited

JVM. Reflection

• KT-79020 Suspend lambdas return type is shown as ??? in reflection
• KT-81967 isSubtypeOf: ClassCastException: CapturedKType cannot be cast to class AbstractKType
• KT-76521 Reflection: change KType representation to avoid dependency on K1
• KT-81619 Reflection: Function supertype of a FunctionN class has flexible type in new implementation
• KT-74529 Context parameters support in reflection
• KT-80901 Reflection: incorrect translation of raw types in the new implementation
• KT-74624 Reflection: KClassifier.createType(...) ignores annotations parameter
• KT-80203 Reflection: provide a way to use legacy K1-based implementation
• KT-80236 Reflection: KType.toString for raw types no longer renders “(raw)”
• KT-79206 Reflection: suspend functional type classifier is null

JavaScript

New Features

• KT-80401 Kotlin/JS support for default export in generated JavaScript
• KT-79284 Use BigInt64Array for LongArray
• KT-79222 K/JS: Allow using Long in exported declarations
• KT-79394 Add the possibility to write common external declarations between JS and WasmJS targets

Performance Improvements

• KT-57128 KJS: Use BigInt to represent Long values in ES6 mode

Fixes

• KT-79928 Allow JsModule/JsNonModule/JsQualifier invocation on per-entity level
• KT-79514 java.lang.IllegalStateException: IrClassSymbolImpl is unbound. Signature: kotlin.js/Promise|null[0] on running jsBrowserTest
• KT-82005 KJS: “TypeError: callAgent.jsonRpcCall_ij3z26_k$ is not a function” after code change in 2.3.0-Beta1/2
• KT-79359 Kotlin/JS: Suspending function doesn’t return Unit on es2015
• KT-79089 KJS: Could not load reporter / Cannot find module ‘mocha’ when running jsNode tests
• KT-56281 KJS: Can't export suspend functions
• KT-79926 Wrong export of interfaces with companions with ES Modules
• KT-80168 Allow @JsStatic inside interface companions
• KT-70222 Remove legacy JS BE-related CLI flags
• KT-81424 Kotlin/JS: Cannot Get / in a simple running application
• KT-80873 KJS: Stdlib requires ES2020-compatible JS engine due to BigInt type literal
• KT-81066 Wasm, JS: Remove redundant logging in compiler output
• KT-72833 KJS: Source maps have incorrect sources paths in per-file
• KT-74055 KJS: @JsPlainObject adds JS code even if marked interface is not used
• KT-72474 KJS: @JsPlainObject doesn't honour -XXLanguage:+JsAllowInvalidCharsIdentifiersEscaping
• KT-79644 BigInt enabled for ES 2015 despite being an ES 2020 feature
• KT-52771 KJS: Pair should be exported to JavaScript
• KT-79704 Unify variance rendering between JS and other backends
• KT-69297 Deprecate referencing inlineable lambdas in js() calls
• KT-80086 [k/js] Resolving imported string literals
• KT-79066 [Kotlin/JS] jsNodeTest fails with SyntaxError when a test file has @file:JsExport and useEsModules() is enabled
• KT-77385 Investigate partial linkage problems for JS HMPP tests
• KT-79628 Remove IR nodes from ExportModel
• KT-79916 K/JS: “Uncaught TypeError” when using ‘Xes-long-as-bigint’ in compose-html
• KT-79050 KJS / IC: “Unexpected body of primary constructor for processing irClass”
• KT-79977 KJS: Long.rotateLeft returns incorrect result when BigInts are enabled
• KT-78831 AbstractFunctionReferencesLowering: fragile fake override generation
• KT-52230 KSJ IR: Applying identity equality operator to Longs always returns false
• KT-6675 KotlinJS: toInt() on external Long throws error
• KT-79184 K/JS: Further intrinsify BigInt-backed Long operations

Klibs

New Features

• KT-80761 K2: [K/N] Should reported klib usage include inheritance

Performance Improvements

• KT-80861 [Klib] Deduplicate IrFileEntry.name
• KT-80866 [Klib] Optimize size of IrFileEntry.line_start_offset
• KT-80438 Uncached KlibMetadataClassDataFinder.findClassData

Fixes

• KT-64237 Klib metadata: migrate to using the common annotations instead of klib-specific extensions in the compiler
• KT-80099 KLIB resolver: Could not find file because of missing klib extension in resolved symlink path
• KT-80999 Reuse existing IrKotlinLibraryLayout in KotlinLibrary for reading pre-processed functions
• KT-80290 Remove if and TODO in countInAsInlinedLambdaArgumentWithPermittedNonLocalReturns
• KT-80298 K/N: one-stage compilation is broken
• KT-79958 KLIB tool fails to render IR if there is IrErrorType in a lirbrary
• KT-75241 Move ExperimentalLibraryAbiReader to a publishable artifact
• KT-76260 Make IrRichCallableReferencesInKlibs lang feature stable in LV=2.3
• KT-61552 [PL] IndexOutOfBoundsException in SAM conversion with substituted function
• KT-74417 Deduce the metadata version based on LV in KLIB-based backends
• KT-75980 [Klib] Reduce serialized size of IrFileEntries for sparse usage of another source files
• KT-73826 Deduplicate IrFileEntry that is serialized inside IrInlinedFunctionBlock

Language Design

• KT-76926 Allow return in expression bodies if return type is specified explicitly
• KT-78866 Show an error for implicit receiver shadowed by context parameter
• KT-81561 Update nested type aliases KEEP to reflect local type aliases support
• KT-81015 Stabilize nested type aliases
• KT-32619 JS: return Promise when continuation is not provided
• KT-78976 Decide if K2 should support local functions inside of local inline functions
• KT-79308 Ability to actualize empty interfaces as Any
• KT-48872 Provide modern and performant replacement for Enum.values()
• KT-28850 Prohibit protected visibility in final expected classes

Libraries

New Features

• KT-81092 Uuid: support generation of version 7 uuids with a given timestamp
• KT-78463 Annotate wasm and JS targets of kotlin-stdlib with @IgnorableReturnValue when appropriate
• KT-74444 EnumEntries type should implement RandomAccess
• KT-78462 Annotate kotlin-stdlib-jvm with @IgnorableReturnValue where appropriate

Performance Improvements

• KT-72111 Change Duration.parseOrNull logic to not throw exceptions internally

Fixes

• KT-82901 Long.MIN_VALUE.milliseconds produces invalid denormalized Duration
• KT-81995 K/N: CMP: Undefined symbol _kfun:kotlin.time.Duration.kotlin.time.Duration
• KT-56822 Deprecate Number.toChar() with error deprecation level
• KT-81078 Increase kotlin.io.createTempDir and createTempFile deprecation level to ERROR
• KT-74493 Deprecate String.subSequence(start, end) with error and drop it in the future
• KT-79192 Increase InputStream.readBytes(Int) deprecation level to HIDDEN
• KT-80778 Stabilize kotlin.time.Clock and kotlin.time.Instant
• KT-81043 String.toBigDecimalOrNull rejects strings accepted by String.toBigDecimal
• KT-81477 Uuid.Companion.generateV* are missing SinceKotlin annotation
• KT-81478 FileTreeWalkTest.withDirectoryFilter fails on Windows
• KT-74411 Introduce Uuid.generateV4() and generateV7()
• KT-80530 Annotate Kotlin/Native stdlib with must-use value/@IgnorableReturnValue when appropriate
• KT-79791 Duration.parse incorrectly handles negative decimal seconds in ISO-8601 format
• KT-80619 [KLIBs] Enable intra-module inliner in stdlib & kotlin-test
• KT-76773 stdlib: contextOf‘s type argument can be inferred via contextOf’s context argument
• KT-71822 Intersection with (subtraction from) an identity set may produce incorrect results
• KT-80431 Remove suppression of “ACTUAL_ANNOTATIONS_NOT_MATCH_EXPECT” from stdlib
• KT-80605 Rename MustUseReturnValue -> MustUseReturnValues
• KT-69947 KLIB stdlib: All intrinsics that can be used in KLIBs with inlined IR must be included in stdlib ABI dump
• KT-59044 Improve various aspects of TimeSource documentation
• KT-80544 Mark controversial path extensions (like .deleteRecursively()) as ignorable
• KT-80603 K/N and K/Wasm: \p{N} category is not supported
• KT-80661 ArrayDeque.lastIndexOf may return -1 for an element present in the deque
• KT-80390 ArrayDeque.indexOf(null) wrongly returns 0 after removals
• KT-79094 Change signature of assertFailsWith or make lambda excluded otherwise
• KT-72028 Incorrect parameters order in IndexedValue documentation
• KT-80130 [stdlib] Commonize AssociatedObjects in commonNonJvmMain
• KT-80107 [stdlib] Move CancellationException to commonNonJvmMain
• KT-80179 Investigate why StringBuilder.length is not enhanced automatically
• KT-80046 Increase test coverage of Duration.parse[IsoString][OrNull] methods
• KT-76459 Remove comments about sorting stability in unsigned-type arrays
• KT-79489 Generate Stdlib API reference for webMain source set
• KT-78243 Drop JS- and Wasm-specific IrLinkageError classes
• KT-79108 Remove the default argument for linkageError from kotlin.js.getPropertyCallableRef
• KT-79130 K/JS: Remove bodies from intrinsified Long methods
• KT-79239 K/Wasm: elementAt extension function of Array/PrimitiveArray/UnsignedArray does not throw IndexOutOfBoundException on incorrect index
• KT-79256 K/Wasm: MatchResult.groups raises a trap on invalid group index
• KT-57317 Repack EnumEntries from stdlib into the compiler

Native

• KT-80620 Bump minimal iOS and tvOS supported versions to 14.0
• KT-80624 Bump minimal watchOS supported versions to 7.0
• KT-79384 K/N: Application Not Responding: Thread Deadlock
• KT-80536 Native: DependencyDownloader seems to have no timeout

Native. Build Infrastructure

• KT-80147 Set proper LV and AV for kotlin-native/performance/buildSrc
• KT-79474 Kotlin/Native: fix breakpad build
• KT-79215 Kotlin/Native: fix distInvalidateStaleCaches on windows

Native. C and ObjC Import

• KT-79752 Native: make cinterop generate CCall.Direct annotations
• KT-79753 Native: support CCall.Direct calls in the compiler
• KT-81312 Native: when -Xccall-mode direct is used, mark unsupported declarations with unresolvable symbol name instead of @Deprecated(ERROR)
• KT-79571 Xcode 26 beta 4: CInteropKT39120TestGenerated.testForwardEnum failed
• KT-80838 Cinterop fails with an error when Compilation works fine
• KT-49034 Kotlin/Native: cnames.structs.Foo resolves into wrong declaration

Native. ObjC Export

• KT-81906 Normalize CFBundleIdentifier when producing Apple framework
• KT-78810 [ObjCExport] Enable explicit ObjC block parameter names by default
• KT-80271 ObjC/Swift Export: Remove Native platform Cloneable checks
• KT-78604 Consider not inheriting KlibScope from KaScope
• KT-79767 ObjCExport: private companion must not be exposed
• KT-79724 ObjCExport: extensions order
• KT-79548 ObjCExport: mangling difference between K1 and K2 when translating KotlinDurationCompanion
• KT-79475 ObjCExport: invalid property getter translation
• KT-79346 ObjCExport: Any method overrides
• KT-78871 ObjCExport: translation of keyword release with parameter generates invalid header

Native. Runtime. Memory

• KT-75918 Native: Deprecate -Xallocator=std
• KT-80678 Native: pagedAllocator=false sweep is slow
• KT-75916 Native: Enable sanitizer support with pagedAllocator=false

Native. Swift Export

Fixes

• KT-81355 Swift Export: Introduce a flag to turn off coroutines export
• KT-80969 Swift Export: Call suspend function as async on swift side
• KT-80111 Swift Export Build Fails Due to Errors in KotlinStdlib.swift
• KT-80884 Swift Export: support async in SIR
• KT-80185 Swift Export: IllegalArgumentException – Collection contains more than one matching element
• KT-79889 K/N: swift-export fails under several different conditions
• KT-79518 Swift export: represent kotlin.Any as swift.any
• KT-78603 Do not inherit SirAndKaSession from KaSession
• KT-79227 Swift Export: Fix First Release Issues
• KT-79521 ‘_CoroutineScope’ is inaccessible due to ‘internal’ protection level
• KT-79181 Swift Export Fails When Using T: Comparable Generic Constraint in Kotlin Classes

Tools. Ant

• KT-75875 Remove Ant support

Tools. BCV

• KT-80313 Add ability to generate dump from jar files [ABI Tools]

Tools. Build Tools API

New Features

• KT-78194 BTA: port the JVM prototype to the new design
• KT-79409 BTA: Support removed compiler arguments properly
• KT-78193 BTA: Implement core infrastructure according to the new design
• KT-78196 BTA: implement API adapter for the prototype implementation
• KT-77999 BTA: Generate BTA options from compiler arguments descriptions

Fixes

• KT-75357 CompilationService.loadImplementation(loader) Expects a ClassLoader, but Fails if its not a URLClassLoader
• KT-73090 Gradle 8.11 kotlin compilation fails when run with -Pkotlin.compiler.runViaBuildToolsApi=true
• KT-81321 Deprecate old BTA prototype API
• KT-81602 BTA: rename KotlinToolchains.jvm @JvmName for a more Java-friendly API
• KT-75356 Failing to pass a -d argument causes Build Tools API to NPE
• KT-81130 BTA: using KotlinVersion from stdlib in the API breaks when using isolated classloader
• KT-78195 BTA: migrate the test infrastructure from the prototype to the new design

Tools. CLI

• KT-81077 Add JVM target bytecode version 25
• KT-79867 CompilerConfiguration.configureSourceRoots puts obfuscated file paths instead of ones passed on classpath to CLIConfigurationKeys.CONTENT_ROOTS
• KT-80348 Expose ‘XXLanguage’ compiler argument as a normal argument
• KT-80428 KMP Separate Compilation: Handle friend dependencies
• KT-74590 Deprecate -Xjvm-default in favor of -jvm-default
• KT-80349 KMP Separate Compilation is enabled on non-KMP compilations
• KT-79982 Fix description of -Xjspecify-annotations
• KT-79403 Improve generator for deprecated CLI arguments
• KT-75968 Set proper lifecycle for all existing compiler arguments
• KT-79293 Create Language Features and compiler argument with parameter for new destructuring features

Tools. Commonizer

• KT-49735 [Commonizer] :commonizeNativeDistribution fails for projects with two or more same native targets
• KT-47523 MPP: Unable to resolve c-interop dependency if platform is included in an intermediate source set with the only target
• KT-48118 Commonized c-interop lib is not attached to common main source set
• KT-46248 MPP: Compile KotlinMetadata fails with Unresolved reference if only one native platform from shared source set is available

Tools. Compiler Plugin API

• KT-82563 Improve compiler error messages to identify incompatible plugins causing compilation failures
• KT-55300 Provide a mechanism to describe ordering and dependencies for compiler plugins
• KT-82099 Compiler plugin ordering has no effect
• KT-74867 LLFirIdePredicateBasedProvider matches local classes when it shouldn't
• KT-52665 Deprecate ComponentRegistrar
• KT-75865 Provide an API for setting the file name for the file with top-level declarations generated by a plugin

Tools. Compiler Plugins

New Features

• KT-81091 [DataFrame] Receivers from FirExpressionResolutionExtension are not resolved in CodeFragment

Fixes

• KT-64339 Symbol Light Classes: No Arg compiler plugin generates synthethic constructor which is not seen from light classes
• KT-80429 Power Assert with “Run test using: IntelliJ”: NoClassDefFoundError (org.jetbrains.kotlin.kotlinx.collections.immutable.ExtensionsKt) during compilation
• KT-79319 Lombok: NullPointerException on mvn compile when importing Java constants
• KT-81348 Incorrect bytecode mentioning error class/package is generated by kotlinx-serialization when private serializer in another module is not accessible
• KT-80944 FirUserTypeRefImpl cannot be cast to class FirResolvedTypeRef in maven project
• KT-80815 NoArg compiler plugin: Promote NO_NOARG_CONSTRUCTOR_IN_SUPERCLASS diagnostic from warning to error
• KT-80822 False positive NO_NOARG_CONSTRUCTOR_IN_SUPERCLASS reported for a class with explicit noargs constructor already present
• KT-53122 Constructors generated with NoArg have no @Metadata and are invisible for the frontend
• KT-74687 Kotlin Lombok: False positive when calling builder on Java record
• KT-80419 Remove bundled jetbrains annotations from kotlin-dataframe-compiler-plugin
• KT-79245 [AtomicFU] Drop K1/JS- and K1/Native-specific testrunners
• KT-79197 DataFrame: Cannot find local variable ‘this@df’ with type Scope0
• KT-73865 Incorrect type is generated for irPropertyReference during K/N transformation

Tools. Compiler plugins. Serialization

• KT-70345 Promote COMPANION_OBJECT_IS_SERIALIZABLE_INSIDE_SERIALIZABLE_CLASS diagnostic to error
• KT-79695 Serialization does not exclude field-less properties in 2.2.20-Beta2
• KT-79246 [Serialization] Drop K1-specific testrunners

Tools. Gradle

New Features

• KT-78199 Gradle: Migrate JVM compilation in KGP to the new BTA
• KT-45161 Gradle: Support registering generated sources with the Kotlin model
• KT-71602 Introduce KotlinTopLevelExtension

Fixes

• KT-67290 Deprecate usage of HasKotlinDependencies inside KotlinCompilation
• KT-80950 KGP breaks configuration cache when signing plugin with GnuPG is applied
• KT-64211 Provide support for the kotlin.internal.compiler.arguments.log.level property while running via build tools api
• KT-81719 Do not register swift export related configurations when it's not required
• KT-78741 Add FUS analytics for klib cross-compilation
• KT-75449 Update deprecation of KotlinJsTestFramework#createTestExecutionSpec
• KT-64273 Gradle: remove symbols deprecated after KT-54312
• KT-74915 Make ExtrasProperty.kt internal
• KT-64992 Remove KotlinCompilation.source
• KT-82068 Workaround iOS Simulator start failure in IT
• KT-79482 Report webMain / webTest usage in FUS metrics
• KT-81199 Deprecate “org.jetbrains.kotlin.android” plugin
• KT-82244 Conflicting warnings when using AGP 9.0.0-alpha with built-in Kotlin disabled
• KT-81161 Gradle plugin api reference: compiler arguments types are not available
• KT-70251 Gradle: hide compiler symbols in KGP
• KT-81837 Run integration tests against AGP 8.13
• KT-77457 Compile against Gradle API 9.0
• KT-79238 Bump minimal supported AGP version to 8.2.2
• KT-75869 KGP JS - Update deprecated constructors
• KT-76720 Raise deprecation level to error for Kotlin*Options properties
• KT-79047 Gradle compileKotlin fails with configuration cache
• KT-81415 BTA: Duplicate daemons when compiling JVM + JS in KGP
• KT-80763 Add redirect link to error message when ‘org.jetbrains.kotlin.android’ plugin is used with built-in Kotlin
• KT-81038 Gradle: remove support for properties disabling precise task outputs backup
• KT-80808 Warning from kotlin-dsl with kotlin(“jvm”) on Gradle < 9.0 doesn’t suggest updating Gradle
• KT-80875 Gradle: runToolInSeparateProcess may fail on Windows with too long command line
• KT-79851 Emit an actionable warning/error on unsupported AV/LV configured by kotlin-dsl
• KT-77458 Run Gradle integration tests against Gradle 9.0
• KT-80172 Error message changes depending on the order of applying ‘org.jetbrains.kotlin.android’ and ‘AGP’ 9.0+ with built-in Kotlin plugin
• KT-76177 Remove deprecated classpath snapshot task inputs
• KT-79339 Remove additionalMetadata from compiler options DSL
• KT-73478 Add module level description
• KT-80083 KGP IT: fix tests on Windows
• KT-79034 Automatically disable cross compilation if it's not supported on the host
• KT-79408 A lot of errors files are created when compile Kotlin
• KT-78827 Rewrite Gradle compiler options DSL generator

Tools. Gradle. BCV

• KT-80687 Add description to Gradle tasks [ABI Validation]
• KT-80621 Move Gradle tasks into suitable groups [ABI Validation]
• KT-78625 Kotlin's built-in BCV generates empty .api files

Tools. Gradle. Compiler plugins

• KT-81827 Add a switch for mapping file tasks in Compose Gradle plugin

Tools. Gradle. JS

Fixes

• KT-79921 Web Tooling Gradle API does not respect webpack reconfiguration
• KT-81009 K/JS, Wasm: Promote deprecation of NPM and Yarn package manager internal functions
• KT-76019 Wasm/JS: Promote phantom-js for Karma deprecation to ERROR
• KT-81005 K/JS, Wasm: Promote deprecation of ExperimentalWasmDsl to Error
• KT-81010 K/JS, Wasm: Promote deprecation of internal JS functions to Error
• KT-81008 K/JS, Wasm: Promote deprecation of ExperimentalDceDsl to Error
• KT-81007 K/JS, Wasm: Promote deprecation of public constructors of JS declarations to Error
• KT-81006 K/JS, Wasm: Promote wasm declarations in “js” package deprecation to Error
• KT-81004 K/JS, Wasm: promote deprecation NodeJsExec.create to Error
• KT-75621 KJS / Gradle: Disable npm in --offline mode
• KT-79910 Wasm, JS: Upgrade NPM versions
• KT-76996 Wasm: js tasks triggers wasm subtasks
• KT-79237 Upgrade NPM dependencies versions

Tools. Gradle. Multiplatform

New Features

• KT-76446 Add kotlin-level dependency block to work the same way as commonMain/commonTest dependencies blocks

Fixes

• KT-61127 Remove scoped resolvable and intransitive DependenciesMetadata configurations used in the pre-IdeMultiplatformImport IDE import
• KT-81980 KGP warning gives incorrect suggestion for AGP application compatibility
• KT-81601 With android.builtInKotlin=false AGP 9.0+, using kotlin-multiplatform plugin will fail with aClass Cast Exception
• KT-81060 KMP stores common compilation dependency resolution in Configuration cache leading to error when deserializing (Android only)
• KT-80720 Gradle import of multiplatform project fails: “Failed to invoke getAssociateWith on KotlinJvmCompilation_Decorated”
• KT-81200 Deprecate ‘androidTarget’
• KT-74005 Implement a prototype of Unified Klib support in Kotlin Gradle Plugin
• KT-77367 [uklib] Project dependency to kotlin-jvm module leads to failure in transform during IDE import
• KT-80785 With android.builtInKotlin=false and android.newDsl=true, using kotlin-android plugin will fail with ClassCastException
• KT-81434 [uklib] androidCompileClasspath resolves java compatibility variant instead of android for uklib library
• KT-81469 [uklib] kmpPublicationStrategy affects resolution during import for androidTarget
• KT-81249 Kotlin 2.2.20 broke KMP implementation of Parcelize
• KT-77066 Promote kotlinArtifacts deprecation to an error
• KT-74955 Remove resources resolution strategy completely
• KT-62614 Remove legacy kotlin-gradle-plugin-model
• KT-79559 AGP complains about configurations resolved at configuration time due to KMP partially resolved dependencies diagnostic
• KT-78993 The value for property ‘*’ property ‘dependencies’ is final and cannot be changed any further
• KT-76200 TestModuleProperties.productionModuleName for JVM module isn't present with 2.1.20-RC
• KT-55312 Replace “ALL_COMPILE_DEPENDENCIES_METADATA” configuration with set of metadata dependencies configurations associated per set
• KT-52216 HMPP / KTOR: False positive “TYPE_MISMATCH” with Throwable descendant
• KT-54312 TCS: Replace CompilationDetails abstract class hierarchy by composable implementation
• KT-55230 Remove metadata dependencies transformation for runtimeOnly scope

Tools. Gradle. Native

• KT-80675 Commonized cinterops between “test” compilations produce an import failure
• KT-77732 commonizeCInterop failed with “Unresolved classifier: platform/posix/size_t”
• KT-81510 commonizeCInterop exception with ‘kotlinNativeBundleConfiguration’ not found
• KT-81134 Native: Gradle configuration failure likely related to Klibs cross-compilation
• KT-77486 Remove bitcode DSL
• KT-64107 Kotlin Gradle plugin allows native binaries to have both debuggable and optimized flags set to true
• KT-74910 Bump destinationDir in CInteropProcess to hidden
• KT-74911 Promote CInteropProcess.konanVersion to hidden
• KT-74864 Enable exporting KDocs by default to ObjC
• KT-72705 K/N: compile task cache can not be used due to ‘artifactVersion’ input property

Tools. Gradle. Swift Export

• KT-81465 Swift Export package is build with wrong target
• KT-81460 [KGP] Crash in SwiftExportRunner due to older stdlib
• KT-79524 NoSuchMethodError: 'java.lang.String org.gradle.api.artifacts.ProjectDependency.getPath() for swift export with dependency export fro gradle < 8.11

Tools. Incremental Compile

• KT-75864 Implement a conservative mechanism of the IC with compiler plugins generated top-level declarations
• KT-55982 K2: Consider global lookups from plugins in incremental compilation
• KT-79504 Implement an API to provide IC lookups from backend plugins
• KT-75657 Fix difference in incremental compilation scenarios in BTA in-process vs daemon compilation mode
• KT-79541 Refactor tracking of files relation in IC
• KT-74628 Incremental compilation runner does not check compiler exit code before mapping sources to classes

Tools. JPS

• KT-77347 Support file-less compatible IC approach

Tools. Kapt

• KT-79138 K2: KAPT Java Stub Gen: Unresolved reference with @kotlin.Metadata in Java in 2.2.0
• KT-79133 K2 kapt: class literal with typealias is not expanded
• KT-79305 K2 kapt: ISE “Cannot evaluate IR expression in annotation” on typealias with unresolved expansion
• KT-79136 K2 kapt: unresolved nested class references in annotation arguments are generated without outer class names
• KT-71786 K2Kapt: Stubs generation does not fail on files with declaration errors
• KT-80843 K2: KAPT: Crash on any data class with duplicate properties: “Sequence contains more than one matching element”
• KT-73411 Remove kapt.use.k2 property and code which allows to use K2 with K1 kapt
• KT-79641 Kapt: too much information is printed in verbose mode

Tools. Maven

• KT-82180 kotlin-maven-plugin: IC succeeds after dependent source deletion
• KT-78201 Maven: migrate JVM compilation to the new BTA
• KT-81414 2.2.20 regression: OOM (Compressed class space) when in-process
• KT-81435 Maven: Improve BTA classloader reusage
• KT-81681 Maven: “NoClassDefFoundError” on a second test run
• KT-81218 Kotlin Maven Plugin 2.2.20: Java classes not resolved with enabled incremental compilation without daemon

Tools. Performance benchmarks

• KT-79709 Add -Xdetailed-perf CLI flag to control verbosity of performance logs
• KT-79226 [K/N] Add performance measurement for native backend lowerings

Tools. REPL

• KT-80062 ReplSnippetLowering sometimes produces IrConstructorCall with too many arguments

Tools. Scripts

• KT-80071 Kotlin script mode produces invalid IR: “value that is not available in the current scope”

Tools. Statistics (FUS)

• KT-77407 Add performance measurement for prefix lowerings
• KT-79455 [FUS] Collect KSP plugin version
• KT-79090 Integrate dynamic stats into MarkdownReportRenderer

Tools. Wasm

• KT-82365 K/Wasm: NodeRun tasks in Wasi depend on kotlinWasmToolingSetup
• KT-81313 K/Wasm: update Node.js to 24.x
• KT-81315 K/Wasm: update Node.js to 25.x
• KT-80582 Multiple reloads when using webpack dev server after 2.2.20-Beta2
• KT-80896 K/Wasm: debug tests only once
• KT-78921 K/Wasm: don't generate empty yarn.lock file

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