Kotlin 2.1.0

Changelog

Analysis API

New Features

• KT-68603 KotlinDirectInheritorsProvider: add an option to ignore non-kotlin results

Performance Improvements

• KT-70757 Performance problem in KaFirVisibilityChecker for KaFirPsiJavaClassSymbol

Fixes

• KT-70437 Class reference is not resolvable
• KT-57733 Analysis API: Use optimized ModuleWithDependenciesScopes in combined symbol providers
• KT-72389 K2: False positive "Redundant 'protected' modifier" for protected property inside protected constructor from private or internal class
• KT-69190 K2: False-positive "redundant private modifier"
• KT-64984 Analysis API: Support Wasm target
• KT-70375 K2: NPE at org.jetbrains.kotlin.analysis.api.fir.symbols.KaFirNamedClassSymbolBase.createPointer
• KT-71259 K2 evaluator: Invalid smart cast info collecting for Code Fragments
• KT-69360 Lack of implicit receiver for the last statement under lambda in scripts
• KT-70890 Analysis API: Experiment with weak references to LL FIR/analysis sessions in session caches
• KT-70657 Analysis API: Inner types from classes with generics are incorrectly represented by the compiled jars
• KT-71055 Suspend calls inside 'analyze()' break the block guarantees
• KT-70815 Analysis API: Implement stop-the-world session invalidation
• KT-69819 K2 IDE: LHS type in callable references is unresolved when it has type arguments and is qualified
• KT-68761 Analysis API: Experiment with limited-size cache in KaFirSessionProvider
• KT-70384 Analysis API Standalone: The same class in the same two renamed jars is unresolved
• KT-71067 Exceptions from references cancel Find Usages
• KT-69535 Redesign 'containingSymbol'
• KT-71025 K2 IDE: Scopes in "importingScopeContext" have reversed ordering and "indexInTower" values
• KT-67483 K2 IDE: Serializable plugin causes infinite resolve recursion when there is a star import from a class with annotation call
• KT-69416 K2 IDE / Completion: “No classifier found” on simple value creating
• KT-70257 CCE: class kotlin.UInt cannot be cast to class java.lang.Number
• KT-70376 K2 IDE / Kotlin Debugger: IAE “Only componentN functions should be cached this way, but got: toString” on evaluating toString() method for value class
• KT-70264 AA: service registration via XML fails with AbstractMethodError in Lint CLI
• KT-69950 Analysis API: Introduce isSubtypeOf(ClassId)
• KT-68625 K2: “lazyResolveToPhase(STATUS) cannot be called from a transformer with a phase STATUS.”
• KT-67665 K2: contract violation for value class with a constructor parameter with an implicit type
• KT-67009 Analysis API: Add abbreviated type tests for type aliases from source modules
• KT-69977 KaFirFunctionalType#getAbbreviation is always null
• KT-68341 Analysis API: Expanded function types from libraries don't have an abbreviated type
• KT-68857 Analysis API: Refactor annotations
• KT-70386 Do not filter out overloads from different libraries in dangling files
• KT-65552 K2: CANNOT_CHECK_FOR_ERASED in KtTypeCodeFragment
• KT-65803 K2: Analysis API: KtFirTypeProvider#getSubstitutedSuperTypes throws an exception in the case of "Wrong number of type arguments"
• KT-68896 Support VirtualFile binary dependency inputs to Analysis API modules
• KT-69395 K2 IDE: incorrect overload selection from binary dependencies in a shared native source set
• KT-68573 ISE: "Unexpected constant value (kotlin/annotation/AnnotationTarget, CLASS)" at Kt1DescUtilsKt.toKtConstantValue()
• KT-69576 Analysis API: FIR implementation of "isImplicitReferenceToCompanion" returns false for companion references in implicit invoke operator calls
• KT-69568 Analysis API: FIR implementation of "isImplicitReferenceToCompanion" returns true for non-companion references in qualified calls
• KT-69436 Analysis API Platform: Encapsulate LLFirDeclarationModificationService as an engine service
• KT-63004 K2: Analysis API: Design API for querying declarations generated by compiler plugins (similar to indices)
• KT-69452 AA FIR: wrong source PSI after compile-time evaluation
• KT-69598 AA: definitely not-null type at receiver position should be wrapped in parenthesis
• KT-60484 Analysis API: add support for KtType pointers similar to KtSymbolPointer
• KT-68884 Analysis API: Rename/deprecate/remove declarations as part of Stabilization
• KT-69453 AA FIR: miss to handle expected type of lambda with explicit label
• KT-69533 Protect implementation parts of Analysis API with opt-in annotations

Analysis API. FIR

Performance Improvements

• KT-71566 FirElementBuilder#getFirForNonKtFileElement should iterate a Psi file over and over
• KT-71224 Analysis API: FirElementFinder.collectDesignationPath relies on naive iteration through FIR files

Fixes

• KT-70327 Analysis API: Batch inspection causes deadlock in ValueWithPostCompute
• KT-69070 Analysis API: Querying declared member scope for Java symbols results in exception in some use cases
• KT-68268 LLSealedInheritorsProvider: reduce scope to kotlin files
• KT-69671 TYPES phase contract violation through JavaSymbolProvider
• KT-70624 Declaration symbols from code fragments are treated as not local
• KT-70662 NPE: FirLazyBodiesCalculatorKt.calculateLazyBodyForProperty
• KT-70859 Do not fail highlighting due to resolution problems
• KT-70474 FirLazyResolveContractViolationException from JavaSymbolProvider
• KT-70323 FirLazyResolveContractViolationException: lazyResolveToPhase(TYPES) cannot be called from a transformer with a phase TYPES
• KT-71567 LLFirCompilerRequiredAnnotationsTargetResolver should calculate annotation arguments on demand
• KT-71584 getNonLocalContainingOrThisDeclaration treats KtParameter from functional type as non-local

Analysis API. Light Classes

Performance Improvements

• KT-69998 Drop redundant cache from ClassInnerStuffCache

Fixes

• KT-69833 Support value classes
• KT-71693 Wrong name mangling for JvmField class property and companion property clash
• KT-71469 KtLightClassForDecompiledDeclaration: missed kotlinOrigin
• KT-70710 Provide light classes for KMP modules in Android Lint
• KT-70548 SLC: text of class object access expression is not the same as raw text
• KT-70572 SLC: missing isInheritor implementation for type parameter
• KT-70491 SLC: inconsistent source PSI of no-arg constructor for all default values
• KT-70458 SLC: missed auxiliaryOriginalElement for delegated property
• KT-70232 Support a companion object inside value classes
• KT-70349 @delegate:` annotations are missed for light class fields
• KT-68328 Move KtLightClassBase to ULC

Analysis API. Providers and Caches

• KT-65618 K2: resulted FirClass.psi != requested PsiClass from completion
• KT-69292 K2: Analysis API: A property's MUST_BE_INITIALIZED diagnostic is not updated after changing field usage in an accessor
• KT-71468 Drop redundant logic from LLFirJavaFacadeForBinaries
• KT-71700 Cache result of resolveToCall
• KT-71520 Analysis API: LLFirNativeForwardDeclarationsSymbolProvider spends a lot of time in indices

Analysis API. Standalone

• KT-65110 Analysis API: In Standalone mode the order of symbols is unstable

Analysis API. Stubs and Decompilation

• KT-71565 KtClassOrObject should use isLocal from greenStub

Analysis API. Surface

New Features

• KT-69960 resolveToCallCandidates should support operators
• KT-69961 resolveToCallCandidates should support properties

Performance Improvements

• KT-70529 KaSymbol: reduce the number of cached usages
• KT-70165 Introduce PSI-based KaSymbols for K2

Fixes

• KT-69371 Analysis API: expose only interfaces/abstract classes for the resolution API
• KT-69696 KaSymbolByFirBuilder should filter call-site substitutions
• KT-69679 KaDelegatedConstructorCall should have substituted signature
• KT-70206 anonymousSymbol API throws an exception for regular functions
• KT-69699 Receiver type is not substituted in the case of conflict declarations
• KT-69381 Analysis API: Investigate the viability of current KaSymbol caches
• KT-70199 K2: ConcurrentModificationException at FirCallCompleter$LambdaAnalyzerImpl.analyzeAndGetLambdaReturnArguments
• KT-70661 Invalid FirDeclarationOrigin ScriptTopLevelDestructuringDeclarationContainer
• KT-70663 KaFirDestructuringDeclarationSymbol: Failed requirement
• KT-63490 Analysis API: Accessing the Analysis API should be prohibited during dumb mode
• KT-63390 K2: Analysis API: add annotations to KtClassInitializerSymbol
• KT-55124 Design common ancestor for KtValueParameter and KtReceiverParameterSymbol
• KT-71731 directlyOverridenSymbols/allOverridenSymbols works incorrectly for intersection overrides

Apple Ecosystem

• KT-66262 Deprecate and remove support for bitcode embedding from the Kotlin Gradle plugin
• KT-66894 XCFramework task fails when name passed to xcframework DSL is different from framework's name
• KT-65675 XCFrameworkTask produces an xcframework with mismatched casing in embedded frameworks
• KT-69119 xcodeVersion task fails if Xcode isn't installed and apple-specific native targets aren't declared

Backend. Wasm

New Features

• KT-70786 Improve DX of the variable view during debugging in Chrome/Firefox for Kotlin/Wasm
• KT-70331 Support incremental compilation for the Wasm backend
• KT-71686 K/Wasm: Add functions to convert between Kotlin and JS array types
• KT-68185 [WasmJs] Attach js exception object to JsException

Fixes

• KT-71294 Wasm Artifacts/Resource are being loaded relatively instead of absolutely
• KT-71473 K/Wasm: Use --closed-world and related options for Binaryen
• KT-72297 [Wasm] Unused associated object class lead to compiler fail
• KT-72156 custom-formatters.js exists in JAR after publishToMavenLocal but not in the published artifact in Maven public
• KT-65799 K/Wasm: remove default exports from wasm exports
• KT-71800 Wasm compiler: Fix member generation for data classes with an array-type property
• KT-71580 String::toFloat on wasm behaves differently compared to other targets
• KT-71523 K/Wasm: cleanup after fix for KT-71474
• KT-71475 K/Wasm: KClass::qualifiedName returns incorrect result for nested or companion objects
• KT-71474 K/Wasm: KProperty*Impl equals work incorrectly for clabbale reference created in different files or modules
• KT-61130 K/Wasm: Function signatures may clash with base class internal methods from a friend module
• KT-70820 [Kotlin QG] wasm-validator fails when running compile[...]KotlinWasmJsOptimize
• KT-70819 [Kotlin QG] node.js fails when running wasmJs[...]Test KGP tasks
• KT-70394 Investigate increased wasm binary size after switching stdlib compilation to K2
• KT-69627 Remove create###Array functions from WASM stdlib
• KT-68509 Fatal: error validating input in compileProductionExecutableKotlinWasmJsOptimize

Compiler

New Features

• KT-71094 Kotlin/Native incremental compilation: fail compilation if cache build failed
• KT-21908 Support 'when' exhaustiveness checking for generic type parameter with sealed class upper bound
• KT-70679 Kotlin/Native: fill WritableTypeInfo from Swift Export type mapping
• KT-59798 Builder inference is not working when combined with let expression
• KT-54227 Cannot use nullable Nothing as reified type parameter
• KT-71430 Kotlin-to-Java direct actualization implementation
• KT-68163 Expose supplementary compiler warnings via CLI
• KT-69321 Swift export: enable auto-linkage of binary dependencies
• KT-11526 Improve diagnostics for "X overrides nothing"
• KT-49710 False positive NO_ELSE_IN_WHEN with nullable type as receiver
• KT-69729 Support calling super interface Java methods from Kotlin interface
• KT-69508 Improve "Public-API inline function cannot access non-public-API" check for the inline property accessors

Performance Improvements

• KT-71353 FP Kotlin performance degradation (around Cone types hierarchy changes)
• KT-71159 [K2] OOM on large enum classes with fields
• KT-69718 K2: Check for jvm nullability annotations in fir2ir is slow
• KT-68417 Native: LLVM 16 inliner is slow on K/N-produced modules
• KT-63971 K2: Redundant @ParameterName in abbreviated type in metadata

Fixes

• KT-71550 JVM IR: NPE on identity equals of boolean true with null
• KT-72214 -fpass-plugin (clangFlags) is not applied since Kotlin 2.0.20
• KT-68933 CompilationException: Back-end: Could not get inlined class
• KT-72255 Promote jspecify from warning to error
• KT-73065 CCE with context receivers
• KT-61033 K2: implement a diagnostic corresponding to K1's MISSING_BUILT_IN_DECLARATION
• KT-72345 K2: Method 'get' without @Override annotation not called
• KT-71260 K2: Internal compiler error in IrFakeOverrideSymbolBase.getOwner when there is no actual for expect
• KT-72996 false-positive unresolved reference error on an overloaded callable reference in a lambda return position on the left-hand size of an elvis operator
• KT-72552 AutoboxingTransformer fails on during linkage on nested lambdas with cinteroped types
• KT-71751 K2: Skipping code in last statement of lambda
• KT-71121 Kotlin/JS incremental compilation fails with KotlinIllegalArgumentExceptionWithAttachments
• KT-60521 Drop language versions 1.4 and 1.5
• KT-70461 K2: "Inline class types should have the same representation" caused by value class and smart check
• KT-72238 Argument type mismatch in builder inside extension function after ?:
• KT-70306 K2: Lambdas are unserializable: inferred from Java param ? super I
• KT-67383 Incorrect optimisation when optimising for loop with UByte
• KT-68653 Switch latest stable language version in Kotlin project to 2.1
• KT-71708 False negative UNSUPPORTED for collection literals as trailing return value
• KT-72281 K/N: "Failed to wait for cache to be built"
• KT-72017 Enum property reflection returning null KClassifier property for Enum classes defined inside Kotlin Scripts
• KT-69040 PCLA: deal with "deep" calls that can be fully analyzed properly
• KT-69920 K2: java.lang.IllegalArgumentException: FirNamedArgumentExpressionImpl.replaceConeTypeOrNull() during Space project compilation
• KT-69549 Try to move callable reference transformation earlier in pipeline
• KT-63944 Kotlin/Native: Cache flavor selection doesn't respect GC kind
• KT-71649 K2: Put operator on mutableMap<T?, V>() causes crashes on null key
• KT-70667 K2: "Type parameter * has inconsistent bounds" caused by wildcard and where-clause
• KT-70562 @SubclassOptInRequired cannot accept multiple experimental marker
• KT-69407 K2: Compiler crash (Shouldn't be here) due to unresolved reference in FirProjectionRelationChecker
• KT-71508 JAVA_CLASS_INHERITS_KT_PRIVATE_CLASS isn't reported when java class is inherited from an effectively private class
• KT-72178 K2: "Unexpected FirPlaceholderProjectionImpl" exception when using "_" as key type in EnumMap
• KT-70407 Error/warning message for @SubclassOptInRequired-annotated class should provide more context
• KT-72302 K2: no error on type operator in annotation parameter default value
• KT-58820 OPT_IN_USAGE_ERROR's message text does not account for SubclassOptInRequired
• KT-71662 PCLA: a type variable is not fixed on demand to a type containing a not-fixed type variable
• KT-69739 K2: "KotlinIllegalArgumentExceptionWithAttachments: Unexpected FirPlaceholderProjectionImpl" caused by unresolved references
• KT-72154 Dokka fails with not array: KClass<out Annotation> on Kotlin 2.1.20-dev with @SubclassOptInRequired
• KT-70756 K2. Compiler crash with FileAnalysisException on incorrect symbol in nesting lambda
• KT-72173 K2: simple object names from root package are resolved without imports in non-root packages when used as values
• KT-71480 JAVA_CLASS_INHERITS_KT_PRIVATE_CLASS isn't reported while java object isn't created
• KT-71034 Failing compiler/testData/codegen/box/inlineClasses/kt70461.kt
• KT-71016 K/Wasm: Failing compiler/testData/codegen/box/inlineClasses/kt70461.kt
• KT-52469 Deprecate reified type parameter instantiating into intersection types
• KT-71753 PCLA: false-negative operator ambiguity error on fixing a type variable on demand for an operator assignment
• KT-59871 K2: Fix introduced diagnostics
• KT-71563 'llegalStateException: Source classes should be created separately before referencing' when actualized through typealias and java direct actualization
• KT-64741 Avoid leaking ConeTypeVariable types in diagnostics from PCLA
• KT-60447 Builder inference fails to infer generic type argument from local class
• KT-69170 K2: "Unresolved reference" caused by generics and fun interfaces
• KT-71756 K2 evaluator: broken resolve of private members during debug of Kotlin project itself
• KT-68893 Invalid annotation in contract crashes with K2
• KT-71490 K2: missing REDUNDANT_ELSE_IN_WHEN
• KT-64403 Implement BlackBoxCodegenTestSpecGenerated for K2
• KT-71551 JVM IR K1: NPE on generating a function imported from an object from another module
• KT-71210 K2: false negative FUNCTION_CALL_EXPECTED / NESTED_CLASS_ACCESSED_VIA_INSTANCE_REFERENCE with companion objects
• KT-71528 K2/JVM: ClassCastException around Array<Nothing?>
• KT-71228 K2: "IllegalArgumentException: Failed requirement" caused by lambda parameter and class type
• KT-71738 K2: False negative REDECLARATION inside object expression
• KT-71701 K2: false positive CAN_BE_VAL with lateinit and non-in-place lambda
• KT-68694 K2 IDE / Kotlin Debugger: AE “Unresolved reference: <HIDDEN: samples/gen/classes/enum class/EnumClass.lam is invisible” on evaluating private lambda inside enum entry
• KT-70970 K2 IDE / Kotlin Debugger: AE “Only assignable IrValues can be set” on calling overloaded inc() operator on interface
• KT-70824 K2: NoSuchFieldException when evaluating private extension property
• KT-70390 K2 IDE / Kotlin Debugger: can't invoke lambda from private class during evaluation
• KT-68701 K2 IDE / Kotlin Debugger: AE “ERROR_CALL 'Unresolved reference: <HIDDEN: /privateLambda is invisible>#' type=IrErrorType(null)” on evaluating private top-level lambda
• KT-68695 K2 IDE / Kotlin Debugger: AE “Unsupported callable reference” on evaluating ::lateinitStr on private lateinit property
• KT-70861 K2 IDE / Kotlin Debugger: can't evaluate Clazz::class call for private class
• KT-34911 Improve error message for WRONG_ANNOTATION_TARGET: list applicable targets
• KT-71601 K2: When with a subject of type dynamic always considered exhaustive
• KT-33091 Kotlin/Native: Compiler crashes if an external class is declared
• KT-59651 K1/K2: Assertion error on external enum usage attempt
• KT-69939 Extract a category of internal FIR checkers from supplementary FIR checkers
• KT-70850 Pull down typeArguments from ConeKotlinType to ConeClassLikeType
• KT-71117 K2: "IllegalArgumentException: No type for StarProjection" with star projection and function type
• KT-71251 Native & JS K2: Missing check for calling isInitialized inside inline fun
• KT-70161 Native: extracting LLVM 16 on Linux makes the compiler print many "Ignoring unknown extended header keyword 'LIBARCHIVE.creationtime'" messages
• KT-71215 K2: UB due to the erroneous greening of the red code with multiple delegation with java
• KT-59386 K2: Missing CONSTANT_EXPECTED_TYPE_MISMATCH
• KT-69564 Make using -Xuse-k2 compiler flag an error
• KT-69756 TypeOfLowering: don't create constant object nodes before inlining
• KT-66328 K2: implement an error for KT-66324
• KT-71046 K/N: a separate lowering to convert function reference to IrConstantObject
• KT-69223 Drop parallel lowering mode in JVM backend
• KT-70260 @JsPlainObject: improve compiler error if a method is present
• KT-67739 Improve error message when JDK used in -Xjdk-release has corrupted class files
• KT-63964 K2: different naming of classes defined in script in metadata
• KT-70014 Common inference: introduce rigidTypeMarker
• KT-71352 Cannot load script definition class org.gradle.kotlin.dsl.KotlinProjectScriptTemplate
• KT-63502 Getting java.lang.ClassNotFoundException: javaslang.λ during compilation
• KT-66316 Kotlin/Native: make @Escapes annotation required for all external functions
• KT-69653 Prohibit exposing types via type parameters' bounds
• KT-68451 Inconsistent rules of CFA in enum initialization block
• KT-70893 K2: Bogus NO_COMPANION_OBJECT on resolve to private qualifier
• KT-70965 FIR/AA: Initializers for Java annotation arguments mapping capture use-site sessions
• KT-63945 K2: Prevent possible diagnostic loss
• KT-64453 K2: Implement ComposeLikeIr...TestGenerated for K2
• KT-30424 Confusing error message "modality is different"
• KT-70846 Replace ConeKotlinType.nullability with isMarkedNullable on specific types
• KT-56720 K2: false positive MANY_IMPL_MEMBER_NOT_IMPLEMENTED in case of delegation in diamond inheritance
• KT-69937 Define & enforce user-friendly terminology for extended checkers
• KT-64406 K2: Implement CompileKotlinAgainstJavaTestGenerated for K2
• KT-69938 Validate sets of default compiler warnings and supplementary compiler warnings
• KT-68971 Investigate suspicious fragmentation of FIR trees for string literals with interpolation
• KT-71073 Multi-dollar strings: parser grabs too much if backticks follow a short sequence of '$'
• KT-71213 Rethrow exceptions in checkers with some useful attachments
• KT-70395 K2: "Captured Type does not have a classifier" caused by out type and interface hierarchy
• KT-70133 K2: false negative UNINITIALIZED_VARIABLE when postponed lambda is created before initialization
• KT-70625 K2: ClassCastException caused by function reference, star projection and invariant type parameter
• KT-70835 K2: "TYPE_MISMATCH" caused by operator assignment
• KT-70366 K2: "KotlinIllegalArgumentExceptionWithAttachments: Failed to find functional supertype for class "
• KT-68834 Parentheses don't influence calls of any convention operators (except invoke operator) after safe navigation operator
• KT-70358 K2: "java.lang.IllegalArgumentException: No type for StarProjection" when using a star projection on a function type
• KT-69298 K2: "Initializer type mismatch" caused by elvis operator type inference for nullable typealias
• KT-71189 K2: emit 'DELEGATE_SPECIAL_FUNCTION_MISSING' and 'DELEGATE_SPECIAL_FUNCTION_NONE_APPLICABLE' on 'by' keyword
• KT-71178 K2: False negative NO_ELSE_IN_WHEN in when over nullable type with !is Nothing? check
• KT-70812 False positive NO_ELSE_IN_WHEN with nullable type argument as subject
• KT-70947 False positive NO_ELSE_IN_WHEN with DNN subject and nullable sealed class upper bound
• KT-70752 Review diagnostics with whole declaration as range
• KT-71160 K2: Rendering of flexible collection types and arrays is too verbose
• KT-61227 Definitely non-nullable types cause "Any was expected" for @Nullable parameter
• KT-69389 K2: NONE_APPLICABLE instead of more useful "type mismatch" error with overloads and parameter nullability mismatch
• KT-69829 Missed UNRESOLVED_LABEL for label in returns and loops
• KT-61223 JDK 21: new addFirst/addLast and putFirst/putLast methods allow adding nullable value for non-null types
• KT-66742 Supertypes with inaccessible type arguments are allowed
• KT-62906 Type system: consider changing simple type & DNN type relation
• KT-70104 Update the error message for calling super Java interface methods case
• KT-69794 K2: Wrong target is reported for EXPOSED_SUPER_INTERFACE diagnostic
• KT-70724 False-positive UNINITIALIZED_VARIABLE for inline constructor with late-initialized variables
• KT-70749 False-positive UNINITIALIZED_VARIABLE for inline fun with crossinline modifier
• KT-65805 Migrate builtins serializer to K2
• KT-71004 FirSignatureEnhancement#enhance mutates attributes on the original function
• KT-70813 Questionable behavior for calls on ILT receivers
• KT-70208 'when' is not exhaustive for expect Boolean
• KT-69210 Native: tune LLVM optimization pipeline
• KT-70753 K2: Missing non-null assertion on the return value of try-catch block
• KT-70012 EXTENSION_SHADOWED_BY_MEMBER shouldn't be reported for actual declarations
• KT-70837 K2. "Expected FirResolvedTypeRef with ConeKotlinType but was FirImplicitTypeRefImplWithoutSource" on incorrect call with extension fun
• KT-66751 Implement a general deprecation of types with inaccessible type arguments
• KT-68748 K2: Remove irFactory from Fir2IrComponents
• KT-61659 K2: Implement the EXTENSION_SHADOWED_BY_MEMBER warning
• KT-70709 Range for MUST_BE_INITIALIZED shouldn't include property annotations
• KT-63294 Do not use duplicated compiler argument names across the codebase
• KT-70673 False positive NO_ELSE_IN_WHEN with nullable Boolean as subject
• KT-70672 False positive NO_ELSE_IN_WHEN with nullable Enum as subject
• KT-69207 Native: use lld when the compiler produces binaries for a Linux target
• KT-67696 Native: compiler crashes when loading an LLVM bitcode file of unsupported version
• KT-69767 K2: Investigate differences in tests without alias behavior for cyclic expansion
• KT-70617 K2: ClassCastException caused by Java enum with overridden name property
• KT-68796 Non-first invoke operator calls break chained calls of convention operators after safe navigation operator
• KT-67772 K2: Metadata misses NoInfer annotation for unsafeCast result
• KT-70304 [FIR2IR] Missing @NoInfer
• KT-65085 K2: Get rid of special check for unresolved array literals on argument mapping phase
• KT-65066 K1 crashes, K2 doesn't report type mismatch on array literal inside nested annotation call
• KT-49235 Kotlin interface limited to 1000 super types
• KT-69991 K2/JVM: Backend crash with functional types and KFunctions
• KT-7461 Forbid using projection modifiers inside top-level Array in annotation's value parameter
• KT-52315 Legacy keywords (header, impl) break enum definitions
• KT-69499 Native: aggressive inline of runtime procedures causes compiler crash in debug builds
• KT-69737 Native: incompatible target-cpu attributes between runtime and Kotlin code
• KT-69911 Unexpected line numbers in default setter
• KT-61529 K2: Unexpected FirClassLikeSymbol null with -no-jdk
• KT-69475 K2: No "Name contains illegal characters" for package name with dots inside
• KT-69484 Native: remove default values for isObjectType
• KT-70352 K2: False-negative CONFLICTING_UPPER_BOUNDS on Nothing bound
• KT-59781 K2: investigate implicit cast generation in fir2ir vs psi2ir
• KT-70036 [FIR2IR] Fix param name in overridden setter
• KT-68718 [JVM] Generic function is instantiated with wrong type argument
• KT-67983 K2: False negative "Recursive type alias in expansion" at recursive typealiases
• KT-70328 K2: @UnsafeVariance stored in the metadata despite the Source retention
• KT-70313 K2: Don't add Any supertype to kotlin.Nothing compiled from sources
• KT-69982 K2: New errors when executing :kotlin-stdlib:jvmJar
• KT-70169 K2: implement a deprecation error for Synchronized, Throws, JvmField on annotation parameters
• KT-67651 K2: inconsistency in behavior for SAM constructor with flexible type
• KT-63857 K2: Extra operator modifier in metadata
• KT-70182 K2: Set up isOperator flag according to operator naming conventions during building synthetic overrides for Java methods
• KT-20798 Implement a deprecation warning for reified modifier on type parameters of type alias
• KT-68697 K2 IDE / Kotlin Debugger: NSEE “List is empty.” when method reference is used in some place in code
• KT-70157 K2: false positive JAVA_CLASS_INHERITS_KT_PRIVATE_CLASS for a Java private class
• KT-68702 K2 IDE: AE “SyntheticAccessorLowering should not attempt to modify other files!” on evaluating of supermethods toString() and hashCode()
• KT-69509 K2 IDE / Kotlin Debugger: exception in lowering ReplaceKFunctionInvokeWithFunctionInvoke when compiling code fragment
• KT-66323 K2: Clarify contracts of ConeSubstitutorByMap
• KT-69652 K2: False positive "Redundant visibility modifier" with explicitApi()
• KT-65815 K2: False-positive NO_RETURN_IN_FUNCTION_WITH_BLOCK_BODY with inline function returning Nothing?
• KT-60508 K2/stdlib: compilation of common code fails if built-in types are provided as platform sources
• KT-70037 K2: Generate IR body for Any constructor despite that fact it's empty
• KT-69870 K2: False positive NO_VALUE_FOR_PARAMETER for override without default but base with default and with enabled KMP
• KT-69599 K2: Investiage and fix lots of UNRESOLVED_REFERENCE during building stdlib native with K2
• KT-68375 K2: FirPrimaryConstructorSuperTypeChecker fails on generated superclasses
• KT-58309 Deal with test failures inside FirTypeEnhancementTestGenerated
• KT-27112 Implement prohibition of exposing types via type parameters' bounds
• KT-69831 Add long FastJarFS tests to the nightlyFirCompilerTest configuration
• KT-69537 K2: Unintentional behavior caused by InferMoreImplicationsFromBooleanExpressions
• KT-59814 K2: Explore why FirDataFlowAnalyzer strips away value parameters of non top-level-functions
• KT-69069 K2: expect overloads are deprioritized in common code
• KT-69511 KJS / K2: False positive IMPLICIT_BOXING_IN_IDENTITY_EQUALS when comparing dynamic with primitive
• KT-69500 Native: introduce an option to inline less "ALWAYS_INLINE" runtime procedures
• KT-69717 K2: Don't call coneType/coneTypeOrNull extensions on FirResolvedTypeRef
• KT-60440 K2/Java: investigate constructor own type parameters enhancement
• KT-69871 K2 allows modifier keywords on package declaration
• KT-61271 Frontend: "The label does not denote a loop." error message is used even if the label does denote a loop
• KT-69768 K2: Investigate differences in tests without alias behavior with typealias to enum entry
• KT-63846 K2: incorrect type argument inferred for smart cast value of a generic type
• KT-69774 Don't report overload resolution ambiguity if extension receiver contains error type
• KT-61316 K2: Consider throwing exception when replaceType is called on special FirExpressions with immutable types
• KT-69201 Discard expect candidate in overload conflict resolver if there is no actual
• KT-69557 K2: Investigate failures with enabled assertion in ConeResolvedAtom constructor
• KT-69783 K2: Make FirTypeProjection sealed
• KT-68000 Investigate getting container functions in checkers
• KT-69649 K2: Cleanup various utilities about toSymbol conversion
• KT-69185 K2: Prepare a test runner for diagnostic tests with type aliases non-expanded automatically
• KT-69390 UNRESOLVED_REFERENCE on call with lambda argument turns whole call red
• KT-68794 K2 IDE / Kotlin Debugger: ISE “No real overrides for FUN FAKE_OVERRIDE name:privateFun visibility:private modality:FINAL” on calling private function from superclass in debugger
• KT-69315 FirJavaGenericVarianceViolationTypeChecker: StackOverflowError
• KT-49962 "Visibility inherited is not allowed in forVisibility" when analyzing broken file
• KT-24212 Report "This class shouldn't be used in Kotlin" on calling constructor of Java class with Kotlin analog
• KT-64195 K2: Consider make FirAnonymousInitializer. containingDeclarationSymbol not null
• KT-64254 "Projections are not allowed on type arguments of functions and properties": Type-project type arguments of properties
• KT-40533 Error message PROPERTY_WITH_NO_TYPE_NO_INITIALIZER for interface property is not fully correct
• KT-20014 Improve diagnostics for lateinit property without initializer and type annotation
• KT-51366 False positive error "Value class cannot extend classes" when extending generic interface with wrong number of type arguments
• KT-68277 K2: false positive UNREACHABLE_CODE for non-local return/break
• KT-69544 K2: Mapped Java @Target annotation's vararg argument has swapped type and elementType
• KT-68998 K2: Refactor postponed atoms
• KT-69288 Native: Apple LLVM 16 fork can't read bitcode with memory attribute produced by upstream LLVM 16
• KT-67808 K2: Inconsistent properties initialization analysis in init blocks in presence of smartcast on this
• KT-69035 K2: Investigate potential removal of FirMangler
• KT-69473 Missing suspend-conversion for lambda in the last statement of when with expected type
• KT-64640 Prevent mutating SequenceCollection methods from JDK 21 be available on read-only collections
• KT-65441 K1: Remove JDK 21 getFirst()/getLast() in (Mutable)List interfaces
• KT-54792 Store program order of properties inside @kotlin.Metadata
• KT-59832 K2: Fix the TODO about merging values for labels in UnusedChecker

Compose compiler

New features

• b/328817808 Added the PausableComposition feature flags
• 83c48a0 Decoy support for JS target is removed from Compose compiler

Fixes

• CMP-6926 iOS compilation failure: Unresolved reference 'copy'
• CMP-6842 FAKE_OVERRIDE declarations are not preserved in metadata and should not be marked with annotations
• CMP-6788 non-private field compilation warnings (stableprop & ComposableSingletons)
• CMP-6685 Native/WASM compilation failure on Composable function with value-type arg + return
• b/376058538 Fix stack overflow when inferring stability of indirect generic loop
• b/339322843 Transform @Composable property delegate references
• b/366040842, b/365066530 Replace deep copy in Compose plugin with in-place type mutation
• b/329477544 Force open / overridden Composable functions to be non-restartable.
• b/361652128 Disable live literal transform if the corresponding flag is disabled
• b/325004814 [Compose] Fix infinite recursion in target analysis
• b/357878245 Disallow open @Composable functions with default params to fix binary compatibility issues.
• b/338597078 [Compose] Fix target warning message
• b/351858979 Fix stability inferencing of interfaces on incremental compilation
• b/346821372 [Compose] Fix code generation for group optimization
• b/339311821 Give warning when stability configuration file is not found
• b/346821372 Fixes group generation for if statements when nonSkippingGroupOptimization is enabled.

IDE. Gradle Integration

• KT-48554 [Multiplatform Import] Ensure consistency between GradleImportProperties and PropertiesProvider

IR. Actualizer

• KT-71631 Kotlin-to-Java direct actualization: java annotation element isn't actualized
• KT-71597 Kotlin-to-Java direct actualization: it is possible to actualize a function with default parameters
• KT-71592 Kotlin-to-Java direct actualization: constructor of nested class can't be actualized
• KT-71577 Kotlin-to-Java direct actualization: method can be actualized by java static method
• KT-69632 K2: Expect actual mismatch on actualization with alias to expect class
• KT-71817 Actualization of static members is broken for non-JVM platforms

IR. Inlining

New Features

• KT-69527 Set the right visibility for synthetic accessors in SyntheticAccessorLowering

Fixes

• KT-71232 Implement an IR validation check that ensures that all IrFields are private on non-JVM backends
• KT-69307 Source offsets seem incorrect after IR inlining
• KT-72884 Internal error in body lowering: IllegalStateException: Can't inline given reference, it should've been lowered
• KT-71659 IR Inliner fails to inline function expressions due to implicit cast from the 1st phase of inlining
• KT-69681 IR: Report warnings on exposure of private types in non-private inline functions
• KT-72521 Kotlin/Native: java.lang.AssertionError: kfun:androidx.compose.runtime#access$<get-androidx_compose_runtime_ProvidedValue$stable>$p$tComposerKt(){}kotlin.Int
• KT-72623 Don't generate synthetic accessors in files other than the one being lowered
• KT-70420 Enable double-inlining in Native & JS backends by default
• KT-67292 Handling assertions before the IR inliner
• KT-70423 KLIB: SyntheticAccessorLowering - generate static factory functions instead of synthetic constructors
• KT-69565 Don't generate synthetic accessors for private symbols inside local classes
• KT-69787 Handle clashes of synthetic accessors generated for top-level callables
• KT-71137 Generate synthetic accessors for backing fields
• KT-67172 Native & JS: Introduce OuterThisInInlineFunctionsSpecialAccessorLowering
• KT-64865 Explicitly generate accessors for private declarations in inline functions
• KT-71657 K/JS: Double-inlining causes failures in IC with top-level synthetic accessors
• KT-71078 Inline all functions in local classes at the 1st stage of inlining
• KT-69802 Don't extract local classes from inline functions in double inlining mode
• KT-66508 IR inliner: Add implicit cast for initializer of temporary variables
• KT-66507 IR inliner: Enable implicit casts in all KLib backends
• KT-69466 IrInlinedFunctionBlock: Refactor it to make it possible to serialize in KLIBs
• KT-69317 IR Inlining. Try to place inlined arguments outside IrInlinedFunctionBlock
• KT-67149 Common Native/JS lowering prefix at the 2nd phase of compilation
• KT-69172 Implement double-inlining for Native
• KT-67304 Keep in common prefix: Shared variables + local classes in inline lambdas
• KT-67170 ArrayConstructorReferenceLowering is missing in Native
• KT-70583 Internal error in body lowering: java.lang.IllegalStateException: An attempt to generate an accessor after all accessors have been already added to their containers
• KT-69700 Inline stub_for_inlining use sites survive after the inliner
• KT-69462 Support dumping IR after inlining in compiler tests
• KT-70693 IR: replace IrReturnableBlock.inlineFucntion with IrInlinedFunctionBlock.inlineFucntion
• KT-70763 IR inline: consider storing stub_for_inline as an inlined function for callable reference
• KT-69168 Wrap assertion calls before IR inliner
• KT-69167 Create intrinsics in stdlib for handling assertions in KLIB-based backends
• KT-69169 Expand assertion intrinsics in backend based on CLI parameters
• KT-69174 Implement the basic Synthetic Accessors Lowering for KLIB-based backends

IR. Interpreter

• KT-70388 K2 IDE / Kotlin Debugger: InterpreterError “Unsupported number of arguments for invocation as builtin function: INT_MAX_POWER_OF_TWO” during evaluation

IR. Tree

Fixes

• KT-69644 Report warning on cross-file IrGetField operations generated by compiler plugins
• KT-68789 Prepare tests for testing visibility (non-)violation in inlined IR
• KT-71826 stdlib fails to compile with -Xserialize-ir=all
• KT-70333 IR: remove ability to apply compiler plugins during KAPT stub generation phase
• KT-67752 Make copyRemappedTypeArgumentsFrom and transformValueArguments methods in DeepCopyIrTreeWithSymbols protected instead of private
• KT-68151 Setup testing visibility of referenced declarations in IR
• KT-68988 [Tests] Streamline the order of irFiles in IR- and Kotlin-like dumps
• KT-65773 Auto generate IR implementation classes
• KT-70330 Automatically keep track of IrValueParameter.index
• KT-68495 Compile-time failure on bounded generic value used in a contains-check with range
• KT-68974 Validate scopes of IrValueParameters in IrValidator

JavaScript

New Features

• KT-70254 K/JS: Generate arrows in ES6 mode instead of anonymous functions
• KT-70283 KJS / ES6: Don't generate bind(this) calls for anonymous functions that capture this

Fixes

• KT-43567 KJS: toString() method and string interpolation of variable produce different code
• KT-70533 KJS: changed string concatenation behavior in 2.0
• KT-14013 JS toString produces different result for nullable/non-nullable ref to the same array
• KT-72732 KJS / ES6: "SyntaxError: 'super' keyword unexpected here" with enabled -Xir-generate-inline-anonymous-functions and disabled arrow functions
• KT-69408 [JS] Enable insertAdditionalImplicitCasts=true (as in other KLIB-based backends)
• KT-71821 K/JS tests are failing with coroutines flow and turbine on timeout
• KT-31799 Allow non-identifier characters in Kotlin/JS (backquoted properties, @JsName)
• KT-55869 Coroutine is not intercepted, when the coroutine is started calling startCoroutineUninterceptedOrReturn using callable reference
• KT-70117 Generate debug info for code from js call
• KT-69642 ES generator-based coroutines rely on eval
• KT-67452 K2: Consider hiding dynamic type creation under FlexibleTypeFactory for JS only
• KT-70226 Delete JS tests that were only run with the legacy JS backend
• KT-71338 K/JS: Add a flag for switching generating arrow functions on & off
• KT-69173 Implement double-inlining for JS
• KT-67327 JS: Remove error tolerance
• KT-69892 Array.isArray() returns false for an instance returned by KtList.asReadonlyArrayView()
• KT-70231 Delete the org.jetbrains.kotlin.cli.js.dce.K2JSDce class
• KT-69928 KJS: keys() and values() of KtMap's JS view don't behave as expected
• KT-70707 KJS: asJsReadonlyMapView does not implement ReadonlyMap correctly
• KT-71220 Fix invalid IrFunctionReference creation in InnerClassConstructorCallsLowering
• KT-70393 Investigate failing JS test after switch stdlib compilation to K2
• KT-64429 K2: Implement KlibJsIrTextTestCaseGenerated for K2
• KT-69587 [Tests] Fix multi-module deserialization in JS irText tests
• KT-70219 Delete the org.jetbrains.kotlin.cli.js.K2JSCompiler class
• KT-70221 Rename org.jetbrains.kotlin.cli.js.K2JsIrCompiler to K2JSCompiler
• KT-70229 Remove test classes related to the legacy JS backend
• KT-70359 Remove legacy backend-related test directives from Kotlin/JS tests
• KT-70362 Clean up Gradle tasks for running JS tests against the legacy JS backend
• KT-66181 Reorganize JsCodeOutliningLowering and keep it before the IR inliner
• KT-30016 JS BE does not generate special bridge methods
• KT-68975 KJS: Investigate calling js(...) from inline functions

KMM Plugin

• KT-71011 AS KMP plugin: ios application can't start for 2024.2.1

Klibs

New Features

• KT-64169 [KLIB Resolve] Don't skip libraries that happen to have the same unique_name
• KT-68322 Compiler (JS, Wasm): warn about incompatible Kotlin stdlib/compiler pair

Fixes

• KT-61098 [KLIB Resolve] Don't allow working with KLIB "repositories"
• KT-72965 Ignore subclassOptInRequired constructor warning
• KT-68792 Bump KLIB ABI version in 2.1
• KT-67474 K2: Missing @ExtensionFunctionType in metadata in KLIBs
• KT-71633 [2.1.0] Suspicious "Argument type mismatch" error
• KT-70146 [KLIB Resolve] Don't fail on nonexistent transitive dependency
• KT-71455 [KLIB Resolve] Forbid passing KLIB unique names via CLI
• KT-67448 [KLIB Resolve] Deprecate passing KLIB unique names via CLI
• KT-67450 [KLIB Resolve] Kotlin/Native: Only one implicit repository should remain for the compiler ("dist")
• KT-70285 Warning about incompatible stdlib (JS/Wasm) is not reported if stdlib is unpacked
• KT-66218 Clean-up the code for serialization & deserialization of DFGs to & from KLIBs
• KT-71414 KotlinLibraryResolver.resolveWithDependencies was evolved in binary incompatible way
• KT-68195 move KlibMetadataProtoBuf to frondend-independent module

Language Design

• KT-54617 Stabilize @SubclassOptInRequired: ability to require opt-in for interface implementation
• KT-54458 Preview of non-local break and continue
• KT-69924 Mention 'if' guard when '&&' is used incorrectly
• KT-71222 Remove @ExperimentalSubclassOptIn from SubclassOptInRequired
• KT-67675 Allow usage of Array<Nothing?>
• KT-70754 Changes in typeOf behaviour for Kotlin/Native
• KT-58659 Prohibit implementing a var property with an inherited val property

Libraries

Performance Improvements

• KT-66715 Performance: faster alternative to String.lines()

Fixes

• KT-71628 Review deprecations in stdlib for 2.1
• KT-69545 Kotlin/Native: Deprecate API marked with FreezingIsDeprecated to error
• KT-56076 K2: build Kotlin standard library
• KT-71660 Stabilize experimental API for 2.1
• KT-54299 Extract org.w3c declarations to separate library from K/Wasm Stdlib
• KT-68027 Document caveats and deincentivise usage of measureTimeMillis
• KT-71581 Update outdated documentation to common lazy and provide samples
• KT-71796 Improve documentation for Path.walk and Path.visitFileTree functions
• KT-68019 Fill in missing package descriptions for standard library documentation
• KT-52181 Native: Inconsistent behaviour of LinkedHashMap#entries on JVM and Native
• KT-71570 Document suspend lambda builder
• KT-65526 Rewrite builtins as expect-actual
• KT-68502 K2: Fix or suppress stdlib K2 warnings
• KT-68731 K2: Handle some formally incompatible expect/actual classes in JVM stdlib
• KT-70378 Implement custom serialization for Uuid
• KT-70005 K/Wasm and K/Native: IntArray.sort - array element access out of bounds
• KT-66764 kotlinx-benchmark: rework on kotlin-compiler-embeddable
• KT-69817 Set up klib binary API validation for stdlib
• KT-68396 Handle some formally incompatible top-level expects/actuals callables
• KT-69524 kotlin.uuid.Uuid: checkHyphenAt - error message always specified index 8
• KT-69327 [native] FloatingPointParser.initialParse works incorrectly for some inputs
• KT-46785 Get rid of !! after readLine() in the standard library

Native

• KT-71435 Native: cannot access class 'objcnames.classes.Protocol'
• KT-49279 Kotlin/Native: update LLVM from 11.1.0 to 16.0.0
• KT-61299 Native: patch LLVM to prevent it from using signal handlers incompatibly with JVM
• KT-69637 Native: our LLVM shouldn't advise submitting bugs to the upstream
• KT-64636 kotlin.incremental.native=true causes IrLinkageError
• KT-69142 ObsoleteWorkersApi and FreezingIsDeprecated is not displayed on targets in webdocs

Native. Build Infrastructure

• KT-71820 Update the coroutines version used in kotlin-native build infrastructure
• KT-69479 Native: remove custom python version building from the LLVM builder container image
• KT-63214 [K/N] llvm build script fails with MacOSX14.0.sdk sysroot

Native. ObjC Export

• KT-62997 IllegalStateException for hashCode(): KClass for Objective-C classes is not supported yet
• KT-59497 KClass.simpleName returns null in ObjC-inherited class

Native. Platform Libraries

• KT-70032 Rebuild platform libraries in 2.1.0 with Xcode 16
• KT-69448 LLVM 16 clang with Xcode 16 headers: 'sys/cdefs.h' file not found

Native. Runtime

• KT-70680 Kotlin/Native: Use WritableTypeInfo when creating Swift wrapper from the runtime
• KT-70568 Native: revert workaround for debug with LLVM 16
• KT-67730 Native: fix runtime compilation warnings after update to LLVM 16

Native. Runtime. Memory

• KT-72624 Native: testRelease_on_unattached_thread sometimes fails with Releasing StableRef with rc 0
• KT-71401 K/N: CMS barrier can be executed on an unregisterred thread
• KT-70364 Kotlin/Native: data race during GC initialization
• KT-68544 [Native] Implement heap dump tool
• KT-70365 Kotlin/Native: make thread id be pointer size

Native. Swift Export

New Features

• KT-71539 Swift Export: export class member overrides
• KT-70442 Swift Export: export class inheritance
• KT-68864 Refactor internal details of swift-export-standalone

Fixes

• KT-70678 Swift Export: generate Kotlin<->Swift type mapping
• KT-70920 Swift Export Nullability: primitive type
• KT-71087 Swift Export: Nullability: Never
• KT-71086 Swift Export: Nullability: Strings
• KT-70919 Swift Export Nullability: reference type
• KT-71026 Swift Export: function overloading with ref types does not work
• KT-70960 Swift Export nullability: add nullability to sir and printer
• KT-70063 Swift export generates invalid Swift code for class and function with the same name
• KT-70069 Swift export: filter out extension properties
• KT-70068 Swift export: nullable types are not marked as unsupported
• KT-69287 Swift Export: support leaking dependencies
• KT-69633 Provide interface for multiple module translation
• KT-69286 [Swift Export][TestInfra] Support translating multiple roots
• KT-69376 Property with Any type does not force addition of import

Reflection

• KT-71378 KotlinReflectionInternalError: Inconsistent number of parameters in the descriptor and Java reflection object

Specification

• KT-53427 Specify @SubclassOptInRequired

Tools. CLI

New Features

• KT-8087 Make it possible to suppress warnings globally in compiler (via command-line option)
• KT-71537 Add JVM target bytecode version 23

Fixes

• KT-70991 K2: Compilation fails if project version has a comma
• KT-70179 K2: Building a file with kotlin-test-junit without junit does not include annotations
• KT-72311 KotlinCliJavaFileManagerImpl caches empty result and broke repeated analyses
• KT-61745 K2: support light tree in multi-module chunk mode
• KT-70885 Errors are not reported for wrong arguments in -Xsuppress-warning flag for non-jvm backends
• KT-69541 K2: "IllegalArgumentException: Unexpected versionNeededToExtract" on using JAR packaged as ZIP64
• KT-69434 K2: Kotlin compiler JarFS can't handle large dependencies (>2GB)
• KT-70959 K2: Support legacy metadata jar format in K2 compiler
• KT-70337 Obsolete code is not removed after refactoring - JvmEnvironmentConfigurator.registerModuleDependencies
• KT-70322 Merge CLITool and CLICompiler classes

Tools. CLI. Native

• KT-68673 Kotlin/Native "You have not specified any compilation arguments. No output has been produced" when no source nor -Xinclude is passed

Tools. Compiler Plugins

Fixes

• KT-72804 Regression in Kotlin 2.1.0: compilation fails when building iOS
• KT-72824 Kotlin power-assert plugin StringIndexOutOfBoundsException
• KT-71658 Transform top-level atomic properties to Java boxed atomics
• KT-65645 Atomicfu-plugin: compilation hangs on a long string concatenation
• KT-69038 Power-Assert does not display const vals
• KT-71525 Setting JvmAbiConfigurationKeys.REMOVE_PRIVATE_CLASSES = true triggers java.util.ConcurrentModificationException
• KT-41888 IrExpression startOffset and endOffset are inconsistent with raw file text
• KT-69856 Compose Plugin: IrType.erasedUpperBound throws NullPointerException when evaluating IrScript nodes due to missing targetClass
• KT-69410 PowerAssert: Cannot find overload of requireNotNull without existing message
• KT-66293 Atomicfu-plugin: wrong return types for lowered extension functions
• KT-69646 PowerAssert: result of array access operator is unaligned
• KT-70112 Power Assert: multiline assertion support
• KT-70504 [atomicfu-plugin] Incremental compilation fails for atomic extensions on JVM
• KT-70351 K2 CodeGen API exception triggered by a compose compiler plugin lowering transformer for data class example
• KT-70113 Power Assert: tab support
• KT-69806 K2: SOE on nested plugin-like annotation in class annotated with itself
• KT-69538 jvm-abi-gen: Remove copy$default if data class constructor is private and ConsistentCopyVisibility is used

Tools. Compiler plugins. Serialization

• KT-70110 Prohibit @Serializable on companion object of another @Serializable class
• KT-69388 Serialization: "You should use ConeClassLookupTagWithFixedSymbol" caused by @Serializable on local generic class

Tools. Daemon

• KT-69929 compileKotlin task reports that daemon has terminated unexpectedly
• KT-72530 The daemon has terminated unexpectedly on startup attempt #1 with error code: Unknown

Tools. Fleet. ObjC Export

Fixes

• KT-71162 ObjCExport: nullable functional type with reference arguments
• KT-71022 ObjCExport: enum c keywords translation
• KT-71082 ObjCExport: KotlinUnit translated as Function1
• KT-70781 ObjCExport: classifiers and callables type parameters translation
• KT-70943 ObjCExport: extension order
• KT-70840 ObjCExport: duplicated interfaces
• KT-70642 ObjCExport: translate collection type arguments as id
• KT-70546 ObjCExport: method generic parameter is lost and translated as id
• KT-70329 ObjCExport: translation and forward of super generic types
• KT-70263 ObjCExport: generic extension support
• KT-69685 ObjCExport: extension translated as not extension
• KT-70318 ObjCExport: translate companion type
• KT-69252 ObjCExport: Get rid of context receivers from ./native/objcexport-header-generator

Tools. Gradle

New Features

• KT-69940 Expose supplementary compiler warnings via KGP
• KT-71603 Introduce KotlinJvmExtension and KotlinAndroidExtension
• KT-70383 KotlinJvmFactory registerKaptGenerateStubsTask() function should also request compilation task provider
• KT-65125 Provide basic support for Swift Export in Kotlin Gradle Plugin
• KT-71602 Introduce KotlinTopLevelExtension
• KT-69927 Need ability to pass KotlinJvmCompilerOptions to registerKotlinJvmCompileTask()
• KT-71227 [Compose] Add PausableComposition feature flag to the Compose Gradle Plugin
• KT-68345 'composeCompiler#stabilityConfigurationFile' doesn't allow setting multiple stability configuration files

Performance Improvements

• KT-65285 Use uncompressed Klibs

Fixes

• KT-71411 Add FUS statistics for new Dokka tasks
• KT-72495 Warn about kotlin-compiler-embeddable loaded along KGP
• KT-70543 Gradle: create migration guide for those who are using Kotlin compiler classes indirectly available in buildscripts
• KT-69329 Compatibility with Gradle 8.9 release
• KT-71291 Log plugins from the list as Gradle plugins
• KT-69255 Deprecate KotlinCompilationOutput#resourcesDirProvider
• KT-61706 Gradle: remove kotlin-compiler-embeddable from build runtime dependencies
• KT-73128 Apply Kotlinlang template for partial HTMLs
• KT-47897 Official Kotlin Gradle plugin api
• KT-58858 Add KDoc documentation for Kotlin Gradle plugin API
• KT-73076 Kotlin Gradle Plugin API Reference: adjust settings
• KT-72387 KGP 2.1.0-RC-227 changes cause KSP to crash calling produceUnpackedKlib
• KT-53280 Gradle plugin leaks some compiler related extensions into API
• KT-69851 Compatibility with Gradle 8.10 release
• KT-65565 Remove deprecated common platform plugin id
• KT-69719 Bump minimal supported Gradle version to 7.6.3
• KT-69721 Bump minimal supported Android Gradle plugin version to 7.3.1
• KT-66944 Relax host requirements on Kotlin klib compilation
• KT-72651 Unable to use target for KotlinBaseApiPlugin.createKotlin(Jvm/Android)Extension()
• KT-72467 kotlin.sourceSets extension not added for KotlinBaseApiPlugin.createKotlinAndroidExtension()
• KT-72303 KGP 2.1.0-Beta2 broke compatibility with KSP
• KT-68596 Update KGP deprecations before 2.1
• KT-67951 Update Compose extension KDoc
• KT-66049 KGP JVM: Publishing isn't compatible with isolated projects and project dependencies
• KT-71405 Compose compiler gradle plugin: project.layout.file can't be used as a value of the 'stabilityConfigurationFiles' option
• KT-71948 KotlinJvmFactory : get rid of replaces with TODO()
• KT-72092 Gradle: use packed klib variant as the default when no packaging attribute is present
• KT-58956 Offer a shared interface for JVM and Android compilerOptions in Project extension
• KT-70251 Gradle: hide compiler symbols in KGP
• KT-70430 Clean-up obsolete Gradle plugin variants for Gradle versions <7.6
• KT-69853 Compile against Gradle API 8.10
• KT-69852 Run Gradle integration tests against Gradle 8.10 release
• KT-65990 Update GradleDeprecatedOption.level values for arguments removed from the DSL after 2.1
• KT-69331 Run tests against Gradle 8.9 release
• KT-69332 Compile against Gradle 8.9 API
• KT-67174 Cleanup old Test DSL
• KT-71071 BuildFusStatisticsIT.testInvalidFusReportDir test failes on Windows
• KT-69585 KGP / Composite Build: "Could not apply withXml() to generated POM" during publishing
• KT-59769 Many "Unexpected exception happened" warnings during build without internet connection

Tools. Gradle. Cocoapods

• KT-63811 cinterop fails to build klib for iosArm64 target when iOS simulator SDK isn't installed
• KT-70500 Remove useLibraries from CocoaPods plugin
• KT-56947 Replace AFNetworking with a smaller library in tests

Tools. Gradle. JS

• KT-69628 K/Wasm: Node.js version per project
• KT-71578 KotlinJS. Webpack does not recompile on changes with per-file
• KT-71536 [JS, Wasm] Stop collecting information about KLIB IC in Kotlin2JsCompile
• KT-70621 Move kotlin-test-js-runner out of Kotlin repository
• KT-67442 KJS / Gradle: kotlinStorePackageLock fails due to OS-dependent lockfile with npm package manager

Tools. Gradle. Multiplatform

New Features

• KT-70469 Add feature flag for Project Isolation and Kotlin Multiplatform
• KT-70897 Add KotlinBaseApiPlugin.kotlinAndroidExtension

Fixes

• KT-71206 KGP: Test source set may get duplicated KLIBs of different versions
• KT-71209 Drop Hierarchy Template diagnostic about used shortcuts
• KT-69412 Change KotlinTargetAlreadyDeclaredChecker's severity from warning to error
• KT-70060 KGP: handleHierarchicalStructureFlagsMigration doesn't support project isolation
• KT-57280 Expose Kotlin Project Structure metadata via consumable configurations instead of accessing all gradle projects directly
• KT-64999 Support Project Isolation with Kotlin Native tasks (XCode integration, Cocoapods etc)
• KT-64998 Granular Metadata Dependencies Transformation is not compatible with Project Isolation
• KT-70650 GenerateProjectStructureMetadata is not compatible with Project Isolation
• KT-71675 checkSandboxAndWriteProtection collides with Compose's syncComposeResources
• KT-66461 Promote compiler options DSL for multiplatform projects to stable
• KT-69323 Don't pass platform dependencies to metadata compilation
• KT-72454 Revert changes made in KT-69899 i.e. make kotlin.android.buildTypeAttribute.keep = false by default again
• KT-70380 KMM App failed to consume android binary lib
• KT-71423 Xcode archive missing dSYM files since Kotlin 2.0.20
• KT-69899 KMP: Publish BuildType by default for android publications with multiple variants
• KT-71428 Change deprecation message for KMP target shorcuts
• KT-58231 Kotlin Gradle Plugin: set deprecation level to Error for KotlinTarget.useDisambiguationClassifierAsSourceSetNamePrefix and overrideDisambiguationClassifierOnIdeImport
• KT-72068 Distribution for klib cross-compilation is not downloaded during compile tasks
• KT-70612 Report incompatibility warning when Project Isolation enabled and Included builds are used
• KT-71529 Deprecate targetFromPreset API with an error
• KT-69614 Deprecate with error ios/tvos/watchos presets
• KT-69974 KMP: POM dependency rewriter doesn't work with Included Builds OR dependencySubstitution
• KT-69472 Remove IncompatibleAgpVersionTooHighWarning diagnostic
• KT-64996 Commonize Native Distribution task is not compatible with Project Isolation
• KT-62911 Export Kotlin Multipaltform Project Coordinates as a secondary variant of apiMetadataElements
• KT-70888 Project isolation: Project cannot dynamically look up a property in the parent project at PropertiesProvider.propertiesWithPrefix
• KT-70688 Move ExperimentalSwiftExportDsl to another package
• KT-58298 AndroidAndJavaConsumeMppLibIT maintenance: Convert to new infrastructure and add test for newer AGP versions
• KT-68976 K2 IDE: Unresolved FileSystem.SYSTEM from OKIO in shared source sets

Tools. Gradle. Native

• KT-67162 KGP: Kotlin/Native with Isolated Projects: kotlinNativeBundleBuildService cannot be changed any futher
• KT-72366 KGP 2.1.0-Beta2 doesn't download kotlin-native-prebuilt when running Dokka
• KT-45559 CInteropProcess: Changes to header files are not recognized; Task is still UP-TO-DATE
• KT-71051 K/N dependencies are re-downloaded multiple times on Windows
• KT-71398 kotlinNativeBundleConfiguration should not contain dependencies on unsupported platforms
• KT-71722 kotlinNativeBundleConfiguration present in JVM-only Gradle project
• KT-55832 Support passing errors to Xcode when configuration cache is enabled
• KT-70690 not possible to build iOS app with Swift Export and Xcode 16
• KT-65838 Remove project usage from PlatformLibrariesGenerator
• KT-70875 KSP1 native tasks fail on configuration phase

Tools. Incremental Compile

• KT-69123 IC: "NoSuchFieldError: No instance field". Not tracking changes to Android ViewBinding class

Tools. JPS

• KT-68565 K2: IllegalStateException: Source classes should be created separately before referencing
• KT-71042 JAVA_MODULE_DOES_NOT_READ_UNNAMED_MODULE when compiling IntelliJ

Tools. Kapt

• KT-72249 K2 KAPT Not picking up use site annontation like K1 Kapt
• KT-69860 K2 kapt: use compiler directly instead of Analysis API
• KT-71776 K2 Kapt in 2.1.0-Beta1 fails with e: java.lang.IllegalStateException: FIR symbol "class org.jetbrains.kotlin.fir.symbols.impl.FirValueParameterSymbol" is not supported in constant evaluation
• KT-70879 Kapt: check that Kotlin 2.1 language features are ignored correctly by K1 kapt
• KT-71431 K2KAPT fails on modules without any annotation processors
• KT-70600 K2 KAPT: inline reified function has a null signature
• KT-70718 Kapt: "error: could not load module " on error type in data class component
• KT-69861 Kapt: use IR to obtain line information instead of PSI

Tools. REPL

• KT-71109 Kotlin Scripting REPL doesn't support keyboard shortcuts

Tools. Scripts

• KT-68685 K2 / Script: "KotlinReflectionInternalError: Unresolved class:" caused by main.kts script with nested classes and reflection
• KT-68545 Using labeled this access to implicit receivers fails in scripts

Tools. Wasm

• KT-67797 Improve the variable view during debugging in Fleet for Kotlin/Wasm
• KT-71506 [Wasm, IC] FUS report for builds with incremental compilation
• KT-70100 wasmJs Target Fails to Compile on ARM64 Linux
• KT-70367 Update binaryen once we get a release with PR 6793
• KT-67863 K/Wasm: Remove ChromeWasmGc
• KT-71360 K/JS & K/Wasm: Upgrade NPM dependencies
• KT-70297 Wasm: Incorrect kotlinJsTestRunner version set in Multi-Project Builds with mixed kotlin-stdlibs