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CHANGELOG

1.4.30-M1

Android

• KT-42383 HMPP: Bad IDEA dependencies: Missing dependency from p1:jvmAndAndroid to p2:jvmAndAndroid

Backend. Native

• KT-38772 Native: support non-reified type parameters in typeOf
• KT-42234 Move LLVM optimization parameters into konan.properties
• KT-42649 IndexOutOfBoundsException during InlineClassTransformer lowering
• KT-42942 Native: optimize peak backend memory by clearing BindingContext after psi2ir
• KT-43198 init blocks inside inline classes
• KT-31072 Don't use non-reified arguments to specialize type operations in IR inliner

Backend. JS

• KT-41227 KJS IR: don't copy to child's prototype references to the function from parent

Backend. IR

• KT-41227 KJS IR: don't copy to child's prototype references to the function from parent

Compiler

New Features

• KT-28055 Consider supporting init blocks inside inline classes
• KT-28056 Consider supporting non-public primary constructors for inline classes
• KT-42094 Allow open callable members in expect interfaces
• KT-43129 FIR: Support OverloadResolutionByLambdaReturnType

Performance Improvements

• KT-41352 JVM IR: reduce bytecode size in for loops and range checks with 'until' by not using inclusive end
• KT-41644 NI: Infinite compilation
• KT-42791 OutOfMemoryError on compilation using kotlin 1.4 on a class with a lot of type inference
• KT-42920 NI: Improve performance around adding constraints

Fixes

• KT-22465 Excessive synthetic method for private setter from superclass
• KT-26229 Lambda/anonymous function argument in parentheses is not supported for callsInPlace effect
• KT-32228 Inconsistent boxing/unboxing for inline classes when interface is specialized by object expression
• KT-32450 Inline class incorrectly gets re-wrapped when provided to a function
• KT-35849 Missing nullability assertion on lambda return value if expected type has generic return value type
• KT-35902 Kotlin generates a private parameterless constructor for constructors taking inline class arguments with default values
• KT-36769 JVM IR: Missing LVT entries for inline function (default) parameters at call site
• KT-36982 JVM IR: SAM adapter classes are generated as synthetic
• KT-37007 JVM IR: extraneous property accessors are generated in multifile facade for InlineOnly property
• KT-37317 [FIR] Add support of extension functions in postponed lambda completion
• KT-38400 FIR: interface abstract is preferred to Any method in super resolve
• KT-38536 JVM IR: bound adapted function references are not inlined
• KT-38656 FIR: determine overridden member visibility properly
• KT-38901 FIR: Make behavior of integer literals overflow consistent with FE 1.0
• KT-39709 [FIR] False positive UNINITIALIZED_VARIABLE in presence of complex graph with jumps
• KT-39923 Result.Failure will get wrapped with Success when using with RxJava
• KT-40198 '$default' methods in 'kotlin/test/AssertionsKt' generated as non-synthetic by JVM_IR
• KT-40262 ACC_DEPRECATED flag not generated for property getter delegate in multifile class facade in JVM_IR
• KT-40282 Inline class wrapping Any gets double boxed
• KT-40464 JVM_IR does not generate LINENUMBER at closing brace of (suspend) lambda
• KT-40948 IllegalAccessError while initializing val property in EXACTLY_ONCE lambda that is passed to another function
• KT-41468 JVM IR: IllegalAccessError on access to abstract base member from another package, from anonymous object inside abstract class
• KT-41493 JVM IR: names of classes for local delegated variables contain the variable name twice
• KT-41792 [FIR] Introduce & use ConeAttribute.UnsafeVariance
• KT-41793 [FIR] Make captured types accessible at the end of resolve
• KT-41809 JVM IR: name for internal $default method doesn't include module name
• KT-41810 JVM IR: Deprecated(HIDDEN) class is incorrectly generated as synthetic
• KT-41841 JVM IR: delegates for private functions with default arguments are generated in multifile classes
• KT-41857 Flaky 'ConcurrentModificationException' through kotlin.serialization.DescriptorSerializer
• KT-41903 JVM IR: do not generate LineNumberTable in auto-generated members of data classes
• KT-41957 JVM IR: step into suspend function goes to the first line of the file
• KT-41960 JVM IR: smart step into members implemented with delegation to interface doesn't work
• KT-41961 JVM IR: line numbers are not generated in JvmMultifileClass facade declarations
• KT-41962 JVM IR: intermittent -1 line numbers in the state machine cause double stepping in the debugger
• KT-42002 JVM / IR: IllegalStateException: "No mapping for symbol: VAR IR_TEMPORARY_VARIABLE" caused by named arguments
• KT-42021 JVM / IR: "IndexOutOfBoundsException: Index 0 out of bounds for length 0" during IR lowering with suspend conversion
• KT-42033 JVM IR: accidental override in Map subclass with custom implementations of some members
• KT-42043 JVM IR: Don't generate collection stubs when implementing methods with more specific return types
• KT-42044 Compiler error when lambda with contract surrounded with parentheses
• KT-42114 JVM_IR generates stub for 'removeIf' in abstract classes implementing 'List' and 'Set'
• KT-42115 JVM_IR doesn't generate 'next' and 'hasNext' method in an abstract class implementing 'ListIterator'
• KT-42116 FIR: Java accessor function should not exist in scope together with relevant property
• KT-42117 IR-based evaluator cannot handle Java static final fields
• KT-42118 FIR2IR: field-targeted annotation is placed on a property, not on a field
• KT-42130 FIR: type variable is observed after when condition analysis
• KT-42132 FIR2IR: companion function reference has no dispatch receiver
• KT-42137 JVM IR: AbstractMethodError on complex hierarchy where implementation comes from another supertype and has a more specific type
• KT-42186 JVM / IR: Infinite cycle in for expression when unsigned bytes are used in decreasing loop range
• KT-42251 JVM / IR: "IllegalStateException: Descriptor can be left only if it is last" when comparing the i-th element of the container of Int? and i with change
• KT-42253 JVM IR: NoSuchFieldError on local delegated property in inline function whose call site happens before declaration in the source
• KT-42281 JVM / IR: AnalyzerException when comparing Int and array that cast to Any in if condition
• KT-42340 FIR2IR: duplicating fake overrides
• KT-42344 IR-based evaluator doesn't support "annotation in annotation"
• KT-42346 FIR: double-vararg in IR while resolving collection literal as Java annotation argument
• KT-42348 FIR: false UNINITIALIZED_VARIABLE in local class
• KT-42350 FIR: false UNINITIALIZED_VARIABLE after initialization in try block
• KT-42351 FIR: false HIDDEN in enum entry member call
• KT-42354 JVM / IR: "AssertionError: Unexpected IR element found during code generation" with KProperty get invocation
• KT-42359 FIR2IR: cannot mangle type parameter
• KT-42373 FIR2IR: local object nested class has no parent if forward-referenced by nested class supertype
• KT-42384 FIR (BE): top-level field has no parent class in BE
• KT-42496 FIR resolve: synthetic property is written but has no setter
• KT-42517 FIR: exception in BE for recursive inline call
• KT-42601 [FIR] Inherited declaration clash for stdlib inheritors
• KT-42642 ISE: No getProgressionLastElement for progression type IntProgressionType
• KT-42650 JVM IR: extraneous nullability annotation on a generic function of a flexible type
• KT-42656 FIR2IR: unsupported callable reference for Java field
• KT-42725 Debugger steps into core library inline functions in chained calls
• KT-42758 JVM / IR: Deserialized object that overrides readResolve() is not reference equal to the singleton instance
• KT-42770 FIR: duplicating signatures in mangler (typealias for functional type)
• KT-42771 FIR: duplicating signature in mangler (data class with delegate)
• KT-42814 FIR: false UNINITIALIZED_VARIABLE in local function after if...else
• KT-42844 FIR: Property write in init block resolved to parameter write
• KT-42846 JVM_IR: NPE on function reference to @JvmStatic method in a different file
• KT-42933 JVM / IR: "AnalyzerException: Expected an object reference, but found I" with local delegate in inline class
• KT-43006 JVM/JVM_IR: do not generate no-arg constructor for constructor with default arguments if there are inline class types in the signature
• KT-43017 JVM / IR: AssertionError when callable reference passed into a function requiring a suspendable function
• KT-43068 JVM IR: no generic signatures for explicitly written methods in a List subclass, whose signature coincides with MutableList methods
• KT-43132 JVM / IR: Method name '<get-...>' in class '...$screenTexts$1$1' cannot be represented in dex format.
• KT-43145 JVM IR: $default methods in multi-file facades are generated as non-synthetic final
• KT-43156 FIR: false UNINITIALIZED_VARIABLE after initialization in synchronized block
• KT-43196 JVM: extra non-static member is generated for extension property in inline class
• KT-43199 JVM IR: synthetic flag for deprecated-hidden is not generated for DeprecatedSinceKotlin and deprecation from override
• KT-43207 JVM IR: no collection stub for iterator is generated on extending AbstractCollection
• KT-43217 JVM_IR: Multiple FAKE_OVERRIDES for java methods using @nonnull Double and java double
• KT-43226 "Incompatible stack heights" with non-local return to outer lambda inside suspend lambda
• KT-43242 JVM / IR: "AnalyzerException: Expected I, but found R" caused by when inside object with @nullable Integer subject
• KT-43249 Wrong code generated for suspend lambdas with inline class parameters
• KT-43286 JVM IR: IAE "Inline class types should have the same representation: Lkotlin/UInt; != I" on smart cast of unsigned type value with JVM target 1.8
• KT-43326 JVM_IR: No deprecated flag for getter of deprecated interface property copied to DefaultImpls
• KT-43327 JVM_IR: No deprecated or synthetic flag for accessors of deprecated-hidden property of unsigned type
• KT-43332 FIR: Smart casts lead to false-positive ambiguity
• KT-43370 JVM IR: No deprecated flag for getter of deprecated property copied via delegation by interface
• KT-43525 Prohibit JvmOverloads on declarations with inline class types in parameters
• KT-43562 JVM IR: incorrect mangling for Collection.size in unsigned arrays
• KT-43584 [FIR] Java annotations with named arguments aren't loaded correctly

IDE

• KT-31553 Complete Statement: Wrong auto-insertion of closing curly brace for a code block
• KT-33466 IDE generates incorrect external override with body for overriding open external method
• KT-39458 Add CLI support for UL classes
• KT-40403 UAST: PsiMethod for invoked extension function/property misses @receiver: annotations
• KT-41406 Kotlin doesn't report annotations for type arguments (no way to add @Nls, @NonNls annotations to String collections in Kotlin)
• KT-41420 UAST does not return information about type annotations
• KT-42754 MPP: no smart cast for Common nullable property used in platform module
• KT-42821 MPP, IDE: Platform-specific errors are reported even when build doesn't target that platform

IDE. Android

• KT-42381 MPP: Bad IDEA dependencies: JVM module depending on built artifact instead of sources of module with Android Plugin applied

IDE. Inspections and Intentions

New Features

• KT-22666 "Create enum constant" quick fix could be provided
• KT-24556 Add Remove quick fix for "Expression under 'when' is never equal to null"
• KT-34121 Report unused result of data class copy method
• KT-34533 INLINE_CLASS_CONSTRUCTOR_NOT_FINAL_READ_ONLY_PARAMETER: Add quickfix "Add val to parameter"
• KT-35215 Quickfix for CONST_VAL_NOT_TOP_LEVEL_OR_OBJECT to remove const modifier
• KT-40251 Intention action to evaluate compile time expression

Fixes

• KT-20420 Intention "Put arguments/parameters on separate lines" doesn't respect the "Place ')' on new line" Kotlin code style setting
• KT-21799 Quickfix "Change function signature" for receiver type doesn't change it
• KT-22665 "Create object" quick fix produce wrong code for enum
• KT-23934 IntelliJ suggest "merge map to joinToString" even when such action is impossible due to suspending actions in map
• KT-30894 Wrong results of intention "Add names to call arguments" when backticked argument starts from digit
• KT-31523 ReplaceWith introduces additional argument name for lambda when named argument is used on call-site
• KT-31833 JavaMapForEachInspection should report for expression with implicit receiver
• KT-33096 Turn 'MapGetWithNotNullAssertionOperator' into an intention
• KT-33212 False positive "map.put() should be converted to assignment" inspection when class inherited from MutableMap has "set" method
• KT-34270 False negative "Join declaration and assignment" with constructor call
• KT-34859 False positive "Should be replaced with Kotlin function" inspection for Character.toString(int) function
• KT-34959 False positive "Redundant overriding method" with different implemented/overridden signatures
• KT-35051 False positive "Remove redundant backticks" if variable inside the string and isn't followed by space
• KT-35097 False positive "Call replaceable with binary operator" on explicit 'equals' call on a platform type value
• KT-35165 "Replace 'if' with elvis operator": don't suggest if val initializer is a complex expression
• KT-35346 False positive 'Make internal' suggestion for function inside interface
• KT-35357 "Move lambda argument out of parentheses" does not preserve block comments
• KT-38349 Invalid suggestion to fold to elvis when having a var-variable
• KT-40704 False negative "Redundant semicolon" at start of line
• KT-40861 "Convert to secondary constructor" intention expected on class name
• KT-40879 False positive "Redundant 'inner' modifier" when calling another inner class with empty constructor
• KT-40985 "Remove explicit type arguments" is suggested when type has an annotation
• KT-41223 False positive "Redundant inner modifier" inspection ignores constructor arguments of object expressions
• KT-41246 False positive "Receiver parameter is never used" with anonymous function expression
• KT-41298 "Remove redundant 'with' call" intention works incorrectly with non-local returns and single-expression functions
• KT-41311 False positive "Redundant inner modifier" when deriving from a nested Java class
• KT-41499 "Convert receiver to parameter" produces code with incorrect order of generic type and function invocation in case of generic function with lambda as a parameter
• KT-41680 False positive "Redundant inner modifier" when deriving from class with non-empty constructor and value passed to it from enclosing class
• KT-42201 Add Opt-In action doesn't work if there is already OptIn annotation
• KT-42255 "Replace elvis expression with 'if' expression" intention shouldn't introduce unnecessary variable if 'error' expression is used

IDE. JS

• KT-43760 KJS: Debugging Kotlin code for Node.js runtime doesn't work

IDE. Scratch

• KT-43415 Kotlin scratch file could not be run and could lead to dead lock

JavaScript

Fixes

• KT-31072 Don't use non-reified arguments to specialize type operations in IR inliner
• KT-39964 Throwable incorrectly implements constructor for (null, cause) args in K/JS-IR
• KT-40090 KJS: IR. Invalid behaviour for optional parameters (redundant tail undefined parameters)
• KT-40686 KJS: Uncaught ReferenceError caused by external class as type inside eventListener in init block
• KT-40771 KJS / IR: "ReferenceError: Metadata is not defined" caused by default parameter value in inner class constructor
• KT-41032 KJS / IR: "AssertionError: Assertion failed" caused by class that is delegated to inherited interface
• KT-41771 KJS / IR: IndexOutOfBoundsException "Index 0 out of bounds for length 0" caused by inline class with List in primary constructor and vararg in secondary
• KT-42025 KJS / IR: IrConstructorCallImpl: No such type argument slot: 0
• KT-42112 KJS: StackOverflowError on @JsExport in case of name clash with function with Enum parameter with star-projection
• KT-42262 KJS: break-statements without label are ignored in a when
• KT-42364 KJS: Properties of interface delegate are non-configurable
• KT-43222 KJS IR: prototype lazy initialization for top-level properties like in JVM
• KT-43313 KJS / IR: "Can't find name for declaration FUN" for secondary constructor

KMM Plugin

• KT-41677 Could not launch iOS project with custom display name
• KT-42463 Launch common tests on local JVM via run gutter
• KT-43188 NoSuchMethodError in New Module Wizard of KMM Project

Libraries

• KT-41112 Docs: add more details about bit shift operations
• KT-41356 Incorrect documentation for rangeTo function

Middle-end. IR

• KT-41765 [Native/IR] Could not resolveFakeOverride()
• KT-42054 Psi2ir: "RuntimeException: IrSimpleFunctionSymbolImpl is already bound" when using result of function with overload resolution by lambda return type

Native

• KT-42822 Kotlin/Native Worker leaks ObjC/Swift autorelease references (and indirectly bridged K/N references) on Darwin targets
• KT-42397 Reverse C interop usage of companion object reports spurious leaks

Native. C and ObjC Import

• KT-42412 [C-interop] Modality of generated property accessors is always FINAL

Native. ObjC Export

• KT-38530 Native: values() method of enum classes is not exposed to Objective-C/Swift

Native. Platform libraries

• KT-43597 Support for Xcode 12.2 SDK

Native. Platforms

• KT-43276 Support watchos_x64 target

Native. Runtime

• KT-42822 Kotlin/Native Worker leaks ObjC/Swift autorelease references (and indirectly bridged K/N references) on Darwin targets

Native. Stdlib

• KT-42428 Inconsistent behavior of map.entries on Kotlin.Native

Reflection

• KT-34024 "KotlinReflectionInternalError: Inconsistent number of parameters" with javaMethod on suspending functions with inline class in function signature or inside the function

Tools. CLI

• KT-43406 JVM: produce deterministic jar files if -d option value is a .jar file

Tools. CLI. Native

• KT-40670 Allow to override konan.properties via CLI

Tools. Compiler Plugins

• KT-41764 KJS /IR IllegalStateException: "Symbol for public kotlin/arrayOf is unbound" with serialization plugin
• KT-42976 kotlinx.serialization + JVM IR: NPE on annotation with @SerialInfo

Tools. Gradle

• KT-38692 KaptGenerateStubs Gradle task will not clean up outputs when sources are empty and not an incremental build
• KT-40140 kotlin-android plugin eagerly creates several Gradle tasks
• KT-41295 Kotlin Gradle Plugin 1.4.20 Configuration Caching bug due to friendPath provider
• KT-42058 Support moduleName option in Kotlin Gradle plugin for JVM
• KT-43054 Implementation of AbstractKotlinTarget#buildAdhocComponentsFromKotlinVariants breaks configuration caching
• KT-43489 Incremental compilation - unable to find history files causing full recompilation

Tools. Gradle. JS

• KT-42400 Kotlin/JS: Gradle DSL: customField() is rejected in Groovy build.gradle
• KT-42462 NPM dependency declaration with Groovy interpolated string
• KT-42954 Kotlin/JS: IDE import after changing kotlin.js.externals.output.format does not re-generate externals
• KT-43535 Common webpack configuration breaks on lambda serialization in some cases

Tools. Gradle. Multiplatform

• KT-42269 Setup default dependsOn edges for Android source sets
• KT-42413 [MPP/gradle] withJava breaks build on 1.4.20-M1
• KT-43141 Gradle / Configuration cache: NPE from org.jetbrains.kotlin.gradle.tasks.KotlinCompileCommon.getKotlinOptions() on reusing configuration cache for task compileCommonMainKotlinMetadata
• KT-43329 Gradle / Configuration cache: IAE “Parameter specified as non-null is null: method KotlinMetadataTargetConfiguratorKt.isCompatibilityMetadataVariantEnabled, parameter $this$isCompatibilityMetadataVariantEnabled” on reusing configuration cache for task compileKotlinMetadata

Tools. Gradle. Native

• KT-39564 Make kotlin-native Gradle tasks Cacheable
• KT-42485 Fail on cinterop: clang_indexTranslationUnit returned 1
• KT-42550 Adding subspec dependency with git location failed
• KT-42849 Gradle / Configuration cache: tasks nativeMetadataJar, runReleaseExecutableNative, runDebugExecutableNative are unsupported and fails on reusing configuration cache
• KT-42938 CocoaPods Gradle plugin: podBuildDependencies doesn't properly report xcodebuild failures
• KT-43151 Gradle / Configuration cache: UPAE “lateinit property binary has not been initialized” on reusing configuration cache for linkDebugExecutableNative, linkDebugTestNative, linkReleaseExecutableNative tasks
• KT-40999 CocoaPods Gradle plugin: Support custom cinterop options when declaring a pod dependency.

Tools. Parcelize

• KT-41553 JVM IR, Parcelize: IrStarProjectionImpl cannot be cast to class IrTypeProjection

Tools. kapt

• KT-34340 Incremental annotation processor recompile all files (only if KAPT enabled).
• KT-36667 Kapt: Add a flag to strip kotlin.Metadata() annotations from stubs
• KT-40493 KAPT does not support aggregating annotations processors in incremental mode
• KT-40882 Kapt stub generation is non-deterministic for incremental compilation
• KT-41788 NullPointerException: Random crashes of build using gradle and kapt because of not calling Processor.init()
• KT-42182 KAPT: Does not consider generated sources for incremental compilation.