Fix minor compile warnings

compiler/backend/src/org/jetbrains/kotlin/codegen/FrameMap.kt

@@ -97,7 +97,7 @@ open class FrameMapBase<T : Any> {
         val descriptors = Lists.newArrayList<Trinity<T, Int, Int>>()
 
         for (descriptor0 in myVarIndex.keys()) {
-            val descriptor = descriptor0 as T
+            @Suppress("UNCHECKED_CAST") val descriptor = descriptor0 as T
             val varIndex = myVarIndex.get(descriptor)
             val varSize = myVarSizes.get(descriptor)
             descriptors.add(Trinity.create(descriptor, varIndex, varSize))

compiler/backend/src/org/jetbrains/kotlin/codegen/ScriptCodegen.kt

@@ -234,7 +234,7 @@ class ScriptCodegen private constructor(
                         hasMain = true
                     }
                 }
-                is KtProperty, is KtNamedFunction, is KtTypeAlias -> genSimpleMember(declaration)
+                is KtProperty, is KtTypeAlias -> genSimpleMember(declaration)
                 is KtClassOrObject -> genClassOrObject(declaration)
                 is KtDestructuringDeclaration -> for (entry in declaration.entries) {
                     genSimpleMember(entry)

compiler/backend/src/org/jetbrains/kotlin/codegen/coroutines/refinedIntTypesAnalysis.kt

@@ -135,10 +135,9 @@ internal fun performRefinedTypeAnalysis(methodNode: MethodNode, thisName: String
         override fun use(frame: VarExpectedTypeFrame, insn: AbstractInsnNode) {
             val (expectedType, sources) = expectedTypeAndSourcesByInsnIndex[insn.index()] ?: return
 
-            sources.flatMap(SourceValue::insns).forEach {
-                insn ->
-                if (insn.isIntLoad()) {
-                    frame.updateExpectedType((insn as VarInsnNode).`var`, expectedType)
+            sources.flatMap(SourceValue::insns).forEach { insnNode ->
+                if (insnNode.isIntLoad()) {
+                    frame.updateExpectedType((insnNode as VarInsnNode).`var`, expectedType)
                 }
             }
         }

compiler/backend/src/org/jetbrains/kotlin/codegen/inline/InlineCodegen.kt

@@ -168,12 +168,12 @@ abstract class InlineCodegen<out T : BaseExpressionCodegen>(
         }
     }
 
+    @Suppress("UNREACHABLE_CODE")
     private fun canSkipStackSpillingOnInline(methodNode: MethodNode): Boolean {
-        // Temporary disable this optimization until
+        // TODO: Temporary disable this optimization until
         // https://issuetracker.google.com/issues/68796377 is fixed
         // or until d8 substitute dex
         return false
-
         // Stack spilling before inline function 'f' call is required if:
         //  - 'f' is a suspend function
         //  - 'f' has try-catch blocks

compiler/backend/src/org/jetbrains/kotlin/codegen/inline/LocalVarRemapper.kt

@@ -96,19 +96,19 @@ class LocalVarRemapper(private val params: Parameters, private val additionalShi
     }
 
     fun visitVarInsn(opcode: Int, `var`: Int, mv: InstructionAdapter) {
-        var opcode = opcode
         val remapInfo = remap(`var`)
         val value = remapInfo.value
         if (value is StackValue.Local) {
             val isStore = isStoreInstruction(opcode)
-            if (remapInfo.parameterInfo != null) {
+            val localOpcode = if (remapInfo.parameterInfo != null) {
                 //All remapped value parameters can't be rewritten except case of default ones.
                 //On remapping default parameter to actual value there is only one instruction that writes to it according to mask value
                 //but if such parameter remapped then it passed and this mask branch code never executed
                 //TODO add assertion about parameter default value: descriptor is required
-                opcode = value.type.getOpcode(if (isStore) Opcodes.ISTORE else Opcodes.ILOAD)
-            }
-            mv.visitVarInsn(opcode, value.index)
+                value.type.getOpcode(if (isStore) Opcodes.ISTORE else Opcodes.ILOAD)
+            } else opcode
+            
+            mv.visitVarInsn(localOpcode, value.index)
             if (remapInfo.parameterInfo != null && !isStore) {
                 StackValue.coerce(value.type, remapInfo.parameterInfo.type, mv)
             }

compiler/backend/src/org/jetbrains/kotlin/codegen/range/inExpression/InFloatingPointRangeLiteralExpressionGenerator.kt

@@ -58,7 +58,7 @@ class InFloatingPointRangeLiteralExpressionGenerator(
                 //      goto jumpLabel
                 //  exitLabel:
 
-                frameMap.useTmpVar(operandType) { argVar ->
+                frameMap.useTmpVar(operandType) { _ ->
                     val exitLabel = Label()
                     genJumpIfFalse(v, exitLabel)
                     v.goTo(jumpLabel)

compiler/backend/src/org/jetbrains/kotlin/codegen/state/GenerationState.kt

@@ -278,8 +278,8 @@ class GenerationState private constructor(
                         ?.let { destination -> SignatureDumpingBuilderFactory(it, File(destination)) } ?: it
                 }
             )
-            .wrapWith(ClassBuilderInterceptorExtension.getInstances(project)) { builderFactory, extension ->
-                extension.interceptClassBuilderFactory(builderFactory, bindingContext, diagnostics)
+            .wrapWith(ClassBuilderInterceptorExtension.getInstances(project)) { classBuilderFactory, extension ->
+                extension.interceptClassBuilderFactory(classBuilderFactory, bindingContext, diagnostics)
             }
 
         this.factory = ClassFileFactory(this, interceptedBuilderFactory)

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/InternalCompilerArgument.kt

@@ -59,7 +59,7 @@ class LanguageSettingsParser : AbstractInternalArgumentParser<ManualLanguageFeat
             return null
         }
 
-        val colon = tail.getOrNull(0) ?: return reportAndReturnNull("Incorrect internal argument syntax, missing colon: $wholeArgument")
+        tail.getOrNull(0) ?: return reportAndReturnNull("Incorrect internal argument syntax, missing colon: $wholeArgument")
 
         val modificator = tail.getOrNull(1)
         val languageFeatureState = when (modificator) {

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/repl/AggregatedReplState.kt

@@ -86,11 +86,12 @@ open class AggregatedReplStageState<T1, T2>(val state1: IReplStageState<T1>, val
     override val history: IReplStageHistory<Pair<T1, T2>> = AggregatedReplStateHistory(state1.history, state2.history, lock)
 
     override fun <StateT : IReplStageState<*>> asState(target: Class<out StateT>): StateT =
-            when {
-                target.isAssignableFrom(state1::class.java) -> state1 as StateT
-                target.isAssignableFrom(state2::class.java) -> state2 as StateT
-                else -> super.asState(target)
-            }
+        @Suppress("UNCHECKED_CAST")
+        when {
+            target.isAssignableFrom(state1::class.java) -> state1 as StateT
+            target.isAssignableFrom(state2::class.java) -> state2 as StateT
+            else -> super.asState(target)
+        }
 
     override fun getNextLineNo() = state1.getNextLineNo()
 

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/repl/ReplState.kt

@@ -57,9 +57,10 @@ interface IReplStageState<T> {
 
     fun getNextLineNo(): Int = history.peek()?.id?.no?.let { it + 1 } ?: REPL_CODE_LINE_FIRST_NO // TODO: it should be more robust downstream (e.g. use atomic)
 
+    @Suppress("UNCHECKED_CAST")
     fun <StateT : IReplStageState<*>> asState(target: Class<out StateT>): StateT =
-            if (target.isAssignableFrom(this::class.java)) this as StateT
-            else throw IllegalArgumentException("$this is not an expected instance of IReplStageState")
+        if (target.isAssignableFrom(this::class.java)) this as StateT
+        else throw IllegalArgumentException("$this is not an expected instance of IReplStageState")
 }
 
 

compiler/cli/src/org/jetbrains/kotlin/cli/common/CLICompiler.kt

@@ -53,7 +53,7 @@ abstract class CLICompiler<A : CommonCompilerArguments> : CLITool<A>() {
         return exec(errStream, Services.EMPTY, MessageRenderer.PLAIN_FULL_PATHS, args)
     }
 
-    public override fun execImpl(baseMessageCollector: MessageCollector, services: Services, arguments: A): ExitCode {
+    public override fun execImpl(messageCollector: MessageCollector, services: Services, arguments: A): ExitCode {
         val performanceManager = performanceManager
         if (arguments.reportPerf || arguments.dumpPerf != null) {
             performanceManager.enableCollectingPerformanceStatistics()
@@ -61,7 +61,7 @@ abstract class CLICompiler<A : CommonCompilerArguments> : CLITool<A>() {
 
         val configuration = CompilerConfiguration()
 
-        val messageCollector = GroupingMessageCollector(baseMessageCollector, arguments.allWarningsAsErrors).also {
+        val collector = GroupingMessageCollector(messageCollector, arguments.allWarningsAsErrors).also {
             configuration.put(CLIConfigurationKeys.MESSAGE_COLLECTOR_KEY, it)
         }
 
@@ -69,8 +69,8 @@ abstract class CLICompiler<A : CommonCompilerArguments> : CLITool<A>() {
         try {
             setupCommonArguments(configuration, arguments)
             setupPlatformSpecificArgumentsAndServices(configuration, arguments, services)
-            val paths = computeKotlinPaths(messageCollector, arguments)
-            if (messageCollector.hasErrors()) {
+            val paths = computeKotlinPaths(collector, arguments)
+            if (collector.hasErrors()) {
                 return ExitCode.COMPILATION_ERROR
             }
 
@@ -93,14 +93,14 @@ abstract class CLICompiler<A : CommonCompilerArguments> : CLITool<A>() {
                     performanceManager.dumpPerformanceReport(File(arguments.dumpPerf!!))
                 }
 
-                return if (messageCollector.hasErrors()) COMPILATION_ERROR else code
+                return if (collector.hasErrors()) COMPILATION_ERROR else code
             } catch (e: CompilationCanceledException) {
-                messageCollector.report(INFO, "Compilation was canceled", null)
+                collector.report(INFO, "Compilation was canceled", null)
                 return ExitCode.OK
             } catch (e: RuntimeException) {
                 val cause = e.cause
                 if (cause is CompilationCanceledException) {
-                    messageCollector.report(INFO, "Compilation was canceled", null)
+                    collector.report(INFO, "Compilation was canceled", null)
                     return ExitCode.OK
                 } else {
                     throw e
@@ -111,10 +111,10 @@ abstract class CLICompiler<A : CommonCompilerArguments> : CLITool<A>() {
         } catch (e: AnalysisResult.CompilationErrorException) {
             return COMPILATION_ERROR
         } catch (t: Throwable) {
-            MessageCollectorUtil.reportException(messageCollector, t)
+            MessageCollectorUtil.reportException(collector, t)
             return INTERNAL_ERROR
         } finally {
-            messageCollector.flush()
+            collector.flush()
         }
     }
 

compiler/daemon/daemon-common/src/org/jetbrains/kotlin/daemon/common/PerfUtils.kt

@@ -134,7 +134,8 @@ class DummyProfiler : Profiler {
     override fun getCounters(): Map<Any?, PerfCounters> = mapOf(null to SimplePerfCounters())
     override fun getTotalCounters(): PerfCounters = SimplePerfCounters()
 
-    override final inline fun <R> withMeasure(obj: Any?, body: () -> R): R = body()
+    @Suppress("OVERRIDE_BY_INLINE")
+    override inline fun <R> withMeasure(obj: Any?, body: () -> R): R = body()
 }
 
 
@@ -149,17 +150,20 @@ abstract class TotalProfiler : Profiler {
 
 
 class WallTotalProfiler : TotalProfiler() {
-    override final inline fun <R> withMeasure(obj: Any?, body: () -> R): R = withMeasureWallTime(total, body)
+    @Suppress("OVERRIDE_BY_INLINE")
+    override inline fun <R> withMeasure(obj: Any?, body: () -> R): R = withMeasureWallTime(total, body)
 }
 
 
 class WallAndThreadTotalProfiler : TotalProfiler() {
-    override final inline fun <R> withMeasure(obj: Any?, body: () -> R): R = withMeasureWallAndThreadTimes(total, threadMXBean, body)
+    @Suppress("OVERRIDE_BY_INLINE")
+    override inline fun <R> withMeasure(obj: Any?, body: () -> R): R = withMeasureWallAndThreadTimes(total, threadMXBean, body)
 }
 
 
 class WallAndThreadAndMemoryTotalProfiler(val withGC: Boolean) : TotalProfiler() {
-    override final inline fun <R> withMeasure(obj: Any?, body: () -> R): R = withMeasureWallAndThreadTimesAndMemory(total, withGC, threadMXBean, body)
+    @Suppress("OVERRIDE_BY_INLINE")
+    override inline fun <R> withMeasure(obj: Any?, body: () -> R): R = withMeasureWallAndThreadTimesAndMemory(total, withGC, threadMXBean, body)
 }
 
 
@@ -169,6 +173,7 @@ class WallAndThreadByClassProfiler() : TotalProfiler() {
 
     override fun getCounters(): Map<Any?, PerfCounters> = counters
 
-    override final inline fun <R> withMeasure(obj: Any?, body: () -> R): R =
-            withMeasureWallAndThreadTimes(counters.getOrPut(obj?.javaClass?.name, { SimplePerfCountersWithTotal(total) }), threadMXBean, body)
+    @Suppress("OVERRIDE_BY_INLINE")
+    override inline fun <R> withMeasure(obj: Any?, body: () -> R): R =
+        withMeasureWallAndThreadTimes(counters.getOrPut(obj?.javaClass?.name, { SimplePerfCountersWithTotal(total) }), threadMXBean, body)
 }

compiler/frontend.java/src/org/jetbrains/kotlin/load/java/structure/impl/JavaClassImpl.kt

@@ -81,10 +81,9 @@ class JavaClassImpl(psiClass: PsiClass) : JavaClassifierImpl<PsiClass>(psiClass)
     override val fields: Collection<JavaField>
         get() {
             assertNotLightClass()
-            return fields(psi.fields.filter { field ->
-                val name = field.name
+            return fields(psi.fields.filter {
                 // ex. Android plugin generates LightFields for resources started from '.' (.DS_Store file etc)
-                name != null && Name.isValidIdentifier(name)
+                Name.isValidIdentifier(it.name)
             })
         }
 

compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/checkers/JvmArrayVariableInLoopAssignmentChecker.kt

@@ -52,6 +52,7 @@ object JvmArrayVariableInLoopAssignmentChecker : AdditionalTypeChecker {
         val resolvedCall = lhsExpression.getResolvedCall(c.trace.bindingContext) ?: return
         val variableDescriptor = resolvedCall.resultingDescriptor as? LocalVariableDescriptor ?: return
         if (variableDescriptor is SyntheticFieldDescriptor) return
+        @Suppress("DEPRECATION")
         if (variableDescriptor.isDelegated) return
 
         val variableType = variableDescriptor.returnType

compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/platform/JvmDefaultSuperCallChecker.kt

@@ -20,7 +20,8 @@ class JvmDefaultSuperCallChecker : CallChecker {
     override fun check(resolvedCall: ResolvedCall<*>, reportOn: PsiElement, context: CallCheckerContext) {
         val jvmDefaultMode = context.languageVersionSettings.getFlag(JvmAnalysisFlags.jvmDefaultMode)
         if (jvmDefaultMode.isEnabled) return
-        val superExpression = getSuperCallExpression(resolvedCall.call) ?: return
+        if (getSuperCallExpression(resolvedCall.call) == null) return
+
         val resultingDescriptor = resolvedCall.resultingDescriptor as? CallableMemberDescriptor ?: return
         if (!resultingDescriptor.hasJvmDefaultAnnotation()) return
 

compiler/frontend.java/src/org/jetbrains/kotlin/synthetic/JavaSyntheticPropertiesScope.kt

@@ -385,14 +385,14 @@ class JavaSyntheticPropertiesScope(storageManager: StorageManager, private val l
             }
         }
 
-        override fun substitute(originalSubstitutor: TypeSubstitutor): PropertyDescriptor? {
-            val descriptor = super.substitute(originalSubstitutor) as MyPropertyDescriptor? ?: return null
+        override fun substitute(substitutor: TypeSubstitutor): PropertyDescriptor? {
+            val descriptor = super.substitute(substitutor) as MyPropertyDescriptor? ?: return null
             if (descriptor == this) return descriptor
 
             val classTypeParameters = (getMethod.containingDeclaration as ClassDescriptor).typeConstructor.parameters
             val substitutionMap = HashMap<TypeConstructor, TypeProjection>()
             for ((typeParameter, classTypeParameter) in typeParameters.zip(classTypeParameters)) {
-                val typeProjection = originalSubstitutor.substitution[typeParameter.defaultType] ?: continue
+                val typeProjection = substitutor.substitution[typeParameter.defaultType] ?: continue
                 substitutionMap[classTypeParameter.typeConstructor] = typeProjection
 
             }

compiler/frontend/src/org/jetbrains/kotlin/analyzer/AnalyzerFacade.kt

@@ -121,6 +121,7 @@ class ResolverForProjectImpl<M : ModuleInfo>(
     // Protected by ("projectContext.storageManager.lock")
     private val moduleInfoByDescriptor = mutableMapOf<ModuleDescriptorImpl, M>()
 
+    @Suppress("UNCHECKED_CAST")
     private val moduleInfoToResolvableInfo: Map<M, M> =
         modules.flatMap { module -> module.flatten().map { modulePart -> modulePart to module } }.toMap() as Map<M, M>
 
@@ -326,6 +327,7 @@ class LazyModuleDependencies<M : ModuleInfo>(
                 yield(moduleDescriptor.builtIns.builtInsModule)
             }
             for (dependency in module.dependencies()) {
+                @Suppress("UNCHECKED_CAST")
                 yield(resolverForProject.descriptorForModule(dependency as M))
             }
             if (module.dependencyOnBuiltIns() == ModuleInfo.DependencyOnBuiltIns.LAST) {
@@ -337,12 +339,16 @@ class LazyModuleDependencies<M : ModuleInfo>(
     override val allDependencies: List<ModuleDescriptorImpl> get() = dependencies()
 
     override val expectedByDependencies by storageManager.createLazyValue {
-        module.expectedBy.map { resolverForProject.descriptorForModule(it as M) }
+        module.expectedBy.map {
+            @Suppress("UNCHECKED_CAST")
+            resolverForProject.descriptorForModule(it as M)
+        }
     }
 
     override val modulesWhoseInternalsAreVisible: Set<ModuleDescriptorImpl>
         get() =
             module.modulesWhoseInternalsAreVisible().mapTo(LinkedHashSet()) {
+                @Suppress("UNCHECKED_CAST")
                 resolverForProject.descriptorForModule(it as M)
             }
 

compiler/frontend/src/org/jetbrains/kotlin/psi/synthetics/SyntheticClassOrObjectDescriptor.kt

@@ -166,6 +166,7 @@ class SyntheticClassOrObjectDescriptor(
 
         override fun getPsiOrParent() = _parent.psiOrParent
         override fun getParent() = _parent.psiOrParent
+        @Suppress("USELESS_ELVIS")
         override fun getContainingKtFile() =
         // in theory `containingKtFile` is `@NotNull` but in practice EA-114080
             _parent.containingKtFile ?: throw IllegalStateException("containingKtFile was null for $_parent of ${_parent.javaClass}")

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/CallCompleter.kt

@@ -439,11 +439,11 @@ class CallCompleter(
         }
 
         var shouldBeMadeNullable = false
-        expressions.asReversed().forEach { expression ->
-            if (!(expression is KtParenthesizedExpression || expression is KtLabeledExpression || expression is KtAnnotatedExpression)) {
-                shouldBeMadeNullable = hasNecessarySafeCall(expression, trace)
+        expressions.asReversed().forEach { ktExpression ->
+            if (!(ktExpression is KtParenthesizedExpression || ktExpression is KtLabeledExpression || ktExpression is KtAnnotatedExpression)) {
+                shouldBeMadeNullable = hasNecessarySafeCall(ktExpression, trace)
             }
-            BindingContextUtils.updateRecordedType(updatedType, expression, trace, shouldBeMadeNullable)
+            BindingContextUtils.updateRecordedType(updatedType, ktExpression, trace, shouldBeMadeNullable)
         }
         return trace.getType(argumentExpression)
     }

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/CallExpressionResolver.kt

@@ -360,7 +360,7 @@ class CallExpressionResolver(
                 initialDataFlowInfoForArguments = initialDataFlowInfoForArguments.disequate(
                     receiverDataFlowValue, DataFlowValue.nullValue(builtIns), languageVersionSettings
                 )
-            } else if (receiver is ReceiverValue) {
+            } else {
                 reportUnnecessarySafeCall(context.trace, receiver.type, callOperationNode, receiver)
             }
         }

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/CallResolverUtil.kt

@@ -145,7 +145,7 @@ fun isBinaryRemOperator(call: Call): Boolean {
     val operator = callElement.operationToken
     if (operator !is KtToken) return false
 
-    val name = OperatorConventions.getNameForOperationSymbol(operator, true, true)
+    val name = OperatorConventions.getNameForOperationSymbol(operator, true, true) ?: return false
     return name in OperatorConventions.REM_TO_MOD_OPERATION_NAMES.keys
 }
 

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/smartcasts/DataFlowValueKindUtils.kt

@@ -41,6 +41,7 @@ internal fun VariableDescriptor.variableKind(
         return propertyKind(usageModule)
     }
 
+    @Suppress("DEPRECATION")
     if (this is LocalVariableDescriptor && this.isDelegated) {
         // Local delegated property: normally unstable, but can be treated as stable in legacy mode
         return if (languageVersionSettings.supportsFeature(LanguageFeature.ProhibitSmartcastsOnLocalDelegatedProperty))

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tower/KotlinToResolvedCallTransformer.kt

@@ -117,6 +117,7 @@ class KotlinToResolvedCallTransformer(
 
                     forwardCallToInferenceSession(baseResolvedCall, context, stub, tracingStrategy)
 
+                    @Suppress("UNCHECKED_CAST")
                     return stub as ResolvedCall<D>
                 }
 
@@ -131,7 +132,8 @@ class KotlinToResolvedCallTransformer(
                     }
                 }
 
-                val resolvedCall = ktPrimitiveCompleter.completeResolvedCall(candidate, baseResolvedCall.diagnostics) as ResolvedCall<D>
+                @Suppress("UNCHECKED_CAST") val resolvedCall =
+                    ktPrimitiveCompleter.completeResolvedCall(candidate, baseResolvedCall.diagnostics) as ResolvedCall<D>
                 forwardCallToInferenceSession(baseResolvedCall, context, resolvedCall, tracingStrategy)
 
                 resolvedCall
@@ -580,6 +582,7 @@ class NewResolvedCallImpl<D : CallableDescriptor>(
     override val argumentMappingByOriginal: Map<ValueParameterDescriptor, ResolvedCallArgument>
         get() = resolvedCallAtom.argumentMappingByOriginal
 
+    @Suppress("UNCHECKED_CAST")
     override fun getCandidateDescriptor(): D = resolvedCallAtom.candidateDescriptor as D
     override fun getResultingDescriptor(): D = resultingDescriptor
     override fun getExtensionReceiver(): ReceiverValue? = extensionReceiver
@@ -639,6 +642,7 @@ class NewResolvedCallImpl<D : CallableDescriptor>(
             }
         }
 
+        @Suppress("UNCHECKED_CAST")
         resultingDescriptor = run {
             val candidateDescriptor = resolvedCallAtom.candidateDescriptor
             val containsCapturedTypes = resolvedCallAtom.candidateDescriptor.returnType?.contains { it is NewCapturedType } ?: false

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tower/ManyCandidatesResolver.kt

@@ -53,6 +53,7 @@ abstract class ManyCandidatesResolver<D : CallableDescriptor>(
         if (callInfo !is PSIErrorCallInfo<*>) {
             throw AssertionError("Error call info for $callInfo should be instance of PSIErrorCallInfo")
         }
+        @Suppress("UNCHECKED_CAST")
         errorCallsInfo.add(callInfo as PSIErrorCallInfo<D>)
     }
 

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tower/NewResolutionOldInference.kt

@@ -260,7 +260,10 @@ class NewResolutionOldInference(
 
     private fun <D : CallableDescriptor> allCandidatesResult(allCandidates: Collection<MyCandidate>) =
         OverloadResolutionResultsImpl.nameNotFound<D>().apply {
-            this.allCandidates = allCandidates.map { it.resolvedCall as MutableResolvedCall<D> }
+            this.allCandidates = allCandidates.map {
+                @Suppress("UNCHECKED_CAST")
+                it.resolvedCall as MutableResolvedCall<D>
+            }
         }
 
     private fun <D : CallableDescriptor> convertToOverloadResults(
@@ -315,6 +318,7 @@ class NewResolutionOldInference(
                 }
             }
 
+            @Suppress("UNCHECKED_CAST")
             resolvedCall as MutableResolvedCall<D>
         }
 
@@ -475,7 +479,7 @@ class NewResolutionOldInference(
             variable: MyCandidate,
             invoke: MyCandidate
         ): MyCandidate {
-            val resolvedCallImpl = VariableAsFunctionResolvedCallImpl(
+            @Suppress("UNCHECKED_CAST") val resolvedCallImpl = VariableAsFunctionResolvedCallImpl(
                 invoke.resolvedCall as MutableResolvedCall<FunctionDescriptor>,
                 variable.resolvedCall as MutableResolvedCall<VariableDescriptor>
             )

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tower/PSICallResolver.kt

@@ -25,7 +25,6 @@ import org.jetbrains.kotlin.resolve.calls.components.CallableReferenceResolver
 import org.jetbrains.kotlin.resolve.calls.components.InferenceSession
 import org.jetbrains.kotlin.resolve.calls.components.PostponedArgumentsAnalyzer
 import org.jetbrains.kotlin.resolve.calls.context.BasicCallResolutionContext
-import org.jetbrains.kotlin.resolve.calls.context.CheckArgumentTypesMode
 import org.jetbrains.kotlin.resolve.calls.context.ContextDependency
 import org.jetbrains.kotlin.resolve.calls.inference.buildResultingSubstitutor
 import org.jetbrains.kotlin.resolve.calls.inference.components.KotlinConstraintSystemCompleter
@@ -551,8 +550,7 @@ class PSICallResolver(
 
         require(oldCall is CallTransformer.CallForImplicitInvoke) { "Call should be CallForImplicitInvoke, but it is: $oldCall" }
 
-        val dispatchReceiver = oldCall.dispatchReceiver!! // dispatch receiver from CallForImplicitInvoke is always not null
-        return resolveReceiver(context, dispatchReceiver, isSafeCall = false, isForImplicitInvoke = true)
+        return resolveReceiver(context, oldCall.dispatchReceiver, isSafeCall = false, isForImplicitInvoke = true)
     }
 
     private fun resolveReceiver(

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tower/PSIKotlinCalls.kt

@@ -39,6 +39,7 @@ val KotlinCall.psiKotlinCall: PSIKotlinCall
         return this as PSIKotlinCall
     }
 
+@Suppress("UNCHECKED_CAST")
 fun <D : CallableDescriptor> KotlinCall.getResolvedPsiKotlinCall(trace: BindingTrace): NewResolvedCallImpl<D>? =
     psiKotlinCall.psiCall.getResolvedCall(trace.bindingContext) as? NewResolvedCallImpl<D>
 

compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/LazyDeclarationResolver.kt

@@ -30,7 +30,7 @@ import org.jetbrains.kotlin.resolve.scopes.MemberScope
 import org.jetbrains.kotlin.storage.LockBasedLazyResolveStorageManager
 import javax.inject.Inject
 
-open class LazyDeclarationResolver @Deprecated("") constructor(
+open class LazyDeclarationResolver constructor(
     globalContext: GlobalContext,
     delegationTrace: BindingTrace,
     private val topLevelDescriptorProvider: TopLevelDescriptorProvider,

compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyClassMemberScope.kt

@@ -464,8 +464,8 @@ open class LazyClassMemberScope(
         descriptor.returnType = c.wrappedTypeFactory.createDeferredType(trace, { thisDescriptor.defaultType })
     }
 
-    override fun recordLookup(name: Name, from: LookupLocation) {
-        c.lookupTracker.record(from, thisDescriptor, name)
+    override fun recordLookup(name: Name, location: LookupLocation) {
+        c.lookupTracker.record(location, thisDescriptor, name)
     }
 
     // Do not add details here, they may compromise the laziness during debugging

compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyPackageMemberScope.kt

@@ -62,8 +62,8 @@ class LazyPackageMemberScope(
         // No extra properties
     }
 
-    override fun recordLookup(name: Name, from: LookupLocation) {
-        c.lookupTracker.record(from, thisDescriptor, name)
+    override fun recordLookup(name: Name, location: LookupLocation) {
+        c.lookupTracker.record(location, thisDescriptor, name)
     }
 
     override fun getClassifierNames(): Set<Name>? = declarationProvider.getDeclarationNames()

compiler/frontend/src/org/jetbrains/kotlin/types/CastDiagnosticsUtil.kt

@@ -24,6 +24,7 @@ import org.jetbrains.kotlin.builtins.isExtensionFunctionType
 import org.jetbrains.kotlin.builtins.isFunctionType
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.ClassKind
+import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.types.checker.KotlinTypeChecker
@@ -163,7 +164,7 @@ object CastDiagnosticsUtil {
         val supertypeWithVariables = TypeCheckingProcedure.findCorrespondingSupertype(subtypeWithVariables, supertype)
 
         val variables = subtypeWithVariables.constructor.parameters
-        val variableConstructors = variables.map { descriptor -> descriptor.typeConstructor }.toSet()
+        val variableConstructors = variables.map(TypeParameterDescriptor::getTypeConstructor).toSet()
 
         val substitution: MutableMap<TypeConstructor, TypeProjection> = if (supertypeWithVariables != null) {
             // Now, let's try to unify Collection<T> and Collection<Foo> solution is a map from T to Foo

compiler/incremental-compilation-impl/src/org/jetbrains/kotlin/incremental/multiproject/ModulesApiHistory.kt

@@ -53,9 +53,8 @@ abstract class ModulesApiHistoryBase(protected val modulesInfo: IncrementalModul
         }
 
         val classFileDirs = classFiles.groupBy { it.parentFile }
-        for ((dir, files) in classFileDirs) {
-            val historyEither = getBuildHistoryForDir(dir)
-            when (historyEither) {
+        for (dir in classFileDirs.keys) {
+            when (val historyEither = getBuildHistoryForDir(dir)) {
                 is Either.Success<Set<File>> -> result.addAll(historyEither.value)
                 is Either.Error -> return historyEither
             }
@@ -107,13 +106,13 @@ class ModulesApiHistoryJvm(modulesInfo: IncrementalModuleInfo) : ModulesApiHisto
 
         val classFileDirs = classFiles.filter { it.exists() && it.parentFile != null }.groupBy { it.parentFile }
         val result = HashSet<File>()
-        for ((dir, files) in classFileDirs) {
-            val historyEither = getBuildHistoryForDir(dir)
-            when (historyEither) {
+        for (dir in classFileDirs.keys) {
+            when (val historyEither = getBuildHistoryForDir(dir)) {
                 is Either.Success<Set<File>> -> result.addAll(historyEither.value)
                 is Either.Error -> return historyEither
             }
         }
+
         return Either.Success(result)
     }
 }

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/IrElementTransformerVoidWithContext.kt

@@ -121,7 +121,7 @@ abstract class IrElementVisitorVoidWithContext : IrElementVisitorVoid {
     }
 
     override final fun visitField(declaration: IrField) {
-        val isDelegated = declaration.descriptor.isDelegated
+        @Suppress("DEPRECATION") val isDelegated = declaration.descriptor.isDelegated
         if (isDelegated) scopeStack.push(ScopeWithIr(Scope(declaration.symbol), declaration))
         visitFieldNew(declaration)
         if (isDelegated) scopeStack.pop()

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/ir/IrUtils.kt

@@ -19,7 +19,9 @@ package org.jetbrains.kotlin.backend.common.ir
 import org.jetbrains.kotlin.backend.common.DumpIrTreeWithDescriptorsVisitor
 import org.jetbrains.kotlin.backend.common.deepCopyWithVariables
 import org.jetbrains.kotlin.backend.common.descriptors.*
-import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.descriptors.ClassKind
+import org.jetbrains.kotlin.descriptors.Modality
+import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.Scope
@@ -43,7 +45,6 @@ import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
 import org.jetbrains.kotlin.ir.types.impl.makeTypeProjection
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
-import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import java.io.StringWriter
 
@@ -160,7 +161,6 @@ fun IrTypeParameter.copyToWithoutSuperTypes(
     shift: Int = 0,
     origin: IrDeclarationOrigin = this.origin
 ): IrTypeParameter {
-    val source = parent as IrTypeParametersContainer
     val descriptor = WrappedTypeParameterDescriptor(symbol.descriptor.annotations, symbol.descriptor.source)
     val symbol = IrTypeParameterSymbolImpl(descriptor)
     return IrTypeParameterImpl(startOffset, endOffset, origin, symbol, name, shift + index, isReified, variance).also { copied ->
@@ -240,7 +240,8 @@ fun IrFunction.copyValueParametersToStatic(
             )
         )
     }
-    source.valueParameters.forEachIndexed { i, oldValueParameter ->
+
+    for (oldValueParameter in source.valueParameters) {
         target.valueParameters.add(
             oldValueParameter.copyTo(
                 target,
@@ -345,6 +346,7 @@ fun IrClass.createImplicitParameterDeclarationWithWrappedDescriptor() {
     assert(descriptor.declaredTypeParameters.isEmpty())
 }
 
+@Suppress("UNCHECKED_CAST")
 fun isElseBranch(branch: IrBranch) = branch is IrElseBranch || ((branch.condition as? IrConst<Boolean>)?.value == true)
 
 fun IrSimpleFunction.isMethodOfAny() =

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/InlineClassDeclarationLowering.kt

@@ -183,31 +183,35 @@ class InlineClassLowering(val context: BackendContext) {
         override fun lower(irFile: IrFile) {
             irFile.transformChildrenVoid(object : IrElementTransformerVoid() {
 
-                override fun visitCall(call: IrCall): IrExpression {
-                    call.transformChildrenVoid(this)
-                    val function = call.symbol.owner
+                override fun visitCall(expression: IrCall): IrExpression {
+                    expression.transformChildrenVoid(this)
+                    val function = expression.symbol.owner
                     if (function.parent !is IrClass ||
                         function.isStaticMethodOfClass ||
                         !function.parentAsClass.isInline ||
                         (function is IrSimpleFunction && !function.isReal) ||
                         (function is IrConstructor && function.isPrimary)
                     ) {
-                        return call
+                        return expression
                     }
 
-                    return irCall(call, getOrCreateStaticMethod(function), dispatchReceiverAsFirstArgument = (function is IrSimpleFunction))
+                    return irCall(
+                        expression,
+                        getOrCreateStaticMethod(function),
+                        dispatchReceiverAsFirstArgument = (function is IrSimpleFunction)
+                    )
                 }
 
-                override fun visitDelegatingConstructorCall(call: IrDelegatingConstructorCall): IrExpression {
-                    call.transformChildrenVoid(this)
-                    val function = call.symbol.owner
+                override fun visitDelegatingConstructorCall(expression: IrDelegatingConstructorCall): IrExpression {
+                    expression.transformChildrenVoid(this)
+                    val function = expression.symbol.owner
                     val klass = function.parentAsClass
                     return when {
-                        !klass.isInline -> call
-                        function.isPrimary -> irCall(call, function)
-                        else -> irCall(call, getOrCreateStaticMethod(function)).apply {
-                            (0 until call.valueArgumentsCount).forEach {
-                                putValueArgument(it, call.getValueArgument(it)!!)
+                        !klass.isInline -> expression
+                        function.isPrimary -> irCall(expression, function)
+                        else -> irCall(expression, getOrCreateStaticMethod(function)).apply {
+                            (0 until expression.valueArgumentsCount).forEach {
+                                putValueArgument(it, expression.getValueArgument(it)!!)
                             }
                         }
                     }

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/phaser/CompilerPhase.kt

@@ -78,6 +78,7 @@ abstract class AbstractNamedPhaseWrapper<in Context : CommonBackendContext, Inpu
         if (this is SameTypeCompilerPhase<*, *> &&
             this !in phaseConfig.enabled
         ) {
+            @Suppress("UNCHECKED_CAST")
             return input as Output
         }
 
@@ -121,7 +122,7 @@ abstract class AbstractNamedPhaseWrapper<in Context : CommonBackendContext, Inpu
             for (post in postconditions) post(output)
             for (post in stickyPostconditions) post(output)
             if (phaseConfig.checkStickyConditions && this is SameTypeCompilerPhase<*, *>) {
-                val phaserStateO = phaserState as PhaserState<Output>
+                @Suppress("UNCHECKED_CAST") val phaserStateO = phaserState as PhaserState<Output>
                 for (post in phaserStateO.stickyPostconditions) post(output)
             }
         }

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/phaser/PhaseBuilders.kt

@@ -17,7 +17,7 @@ private class CompositePhase<Context : CommonBackendContext, Input, Output>(
 ) : CompilerPhase<Context, Input, Output> {
 
     override fun invoke(phaseConfig: PhaseConfig, phaserState: PhaserState<Input>, context: Context, input: Input): Output {
-        var currentState = phaserState as PhaserState<Any?>
+        @Suppress("UNCHECKED_CAST") var currentState = phaserState as PhaserState<Any?>
         var result = phases.first().invoke(phaseConfig, currentState, context, input)
         for ((previous, next) in phases.zip(phases.drop(1))) {
             if (next !is SameTypeCompilerPhase<*, *>) {
@@ -27,6 +27,7 @@ private class CompositePhase<Context : CommonBackendContext, Input, Output>(
             currentState.stickyPostconditions.addAll(previous.stickyPostconditions)
             result = next.invoke(phaseConfig, currentState, context, result)
         }
+        @Suppress("UNCHECKED_CAST")
         return result as Output
     }
 
@@ -36,6 +37,7 @@ private class CompositePhase<Context : CommonBackendContext, Input, Output>(
     override val stickyPostconditions get() = phases.last().stickyPostconditions
 }
 
+@Suppress("UNCHECKED_CAST")
 infix fun <Context : CommonBackendContext, Input, Mid, Output> CompilerPhase<Context, Input, Mid>.then(
     other: CompilerPhase<Context, Mid, Output>
 ): CompilerPhase<Context, Input, Output> {

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/inline/FunctionInlining.kt

@@ -176,8 +176,6 @@ internal class FunctionInlining(val context: Context): IrElementTransformerVoidW
                 }
             }
 
-            val sourceFile = callee.file
-
             val transformer = ParameterSubstitutor()
             statements.transform { it.transform(transformer, data = null) }
             statements.addAll(0, evaluationStatements)

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/transformers/irToJs/IrFileToJsTransformer.kt

@@ -12,8 +12,8 @@ import org.jetbrains.kotlin.js.backend.ast.JsDeclarationScope
 import org.jetbrains.kotlin.js.backend.ast.JsStatement
 
 class IrFileToJsTransformer : BaseIrElementToJsNodeTransformer<JsStatement, JsGenerationContext> {
-    override fun visitFile(declaration: IrFile, context: JsGenerationContext): JsStatement {
-        val fileContext = context.newDeclaration(JsDeclarationScope(context.currentScope, "scope for file ${declaration.path}"))
+    override fun visitFile(declaration: IrFile, data: JsGenerationContext): JsStatement {
+        val fileContext = data.newDeclaration(JsDeclarationScope(data.currentScope, "scope for file ${declaration.path}"))
         val block = fileContext.currentBlock
 
         declaration.declarations.forEach {

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/transformers/irToJs/jsAstUtils.kt

@@ -10,7 +10,9 @@ import org.jetbrains.kotlin.backend.common.ir.isElseBranch
 import org.jetbrains.kotlin.ir.backend.js.utils.JsGenerationContext
 import org.jetbrains.kotlin.ir.backend.js.utils.Namer
 import org.jetbrains.kotlin.ir.declarations.IrFunction
-import org.jetbrains.kotlin.ir.expressions.*
+import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.expressions.IrMemberAccessExpression
+import org.jetbrains.kotlin.ir.expressions.IrWhen
 import org.jetbrains.kotlin.js.backend.ast.*
 
 fun jsVar(name: JsName, initializer: IrExpression?, context: JsGenerationContext): JsVars {
@@ -18,12 +20,12 @@ fun jsVar(name: JsName, initializer: IrExpression?, context: JsGenerationContext
     return JsVars(JsVars.JsVar(name, jsInitializer))
 }
 
-fun <T : JsNode, D : JsGenerationContext> IrWhen.toJsNode(
-    tr: BaseIrElementToJsNodeTransformer<T, D>,
-    data: D,
+fun <T : JsNode> IrWhen.toJsNode(
+    tr: BaseIrElementToJsNodeTransformer<T, JsGenerationContext>,
+    data: JsGenerationContext,
     node: (JsExpression, T, T?) -> T
 ): T? =
-    branches.foldRight<IrBranch, T?>(null) { br, n ->
+    branches.foldRight(null) { br, n ->
         val body = br.result.accept(tr, data)
         if (isElseBranch(br)) body
         else {
@@ -118,9 +120,7 @@ object JsAstUtils {
         thenStatement: JsStatement,
         elseStatement: JsStatement? = null
     ): JsIf {
-        var elseStatement = elseStatement
-        elseStatement = if (elseStatement != null) deBlockIfPossible(elseStatement) else null
-        return JsIf(ifExpression, deBlockIfPossible(thenStatement), elseStatement)
+        return JsIf(ifExpression, deBlockIfPossible(thenStatement), elseStatement?.let { deBlockIfPossible(it) })
     }
 
     fun and(op1: JsExpression, op2: JsExpression): JsBinaryOperation {

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/utils/AnnotationUtils.kt

@@ -21,6 +21,7 @@ object JsAnnotations {
     val jsQualifierFqn = FqName("kotlin.js.JsQualifier")
 }
 
+@Suppress("UNCHECKED_CAST")
 private fun IrCall.getSingleConstStringArgument() =
     (getValueArgument(0) as IrConst<String>).value
 

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmIrCodegenFactory.kt

@@ -31,7 +31,7 @@ class JvmIrCodegenFactory(private val phaseConfig: PhaseConfig) : CodegenFactory
 
         val psi2ir = Psi2IrTranslator(state.languageVersionSettings)
         val psi2irContext = psi2ir.createGeneratorContext(state.module, state.bindingContext, extensions = JvmGeneratorExtensions)
-        val irModuleFragment = psi2ir.generateModuleFragment(psi2irContext, files as Collection<KtFile>)
+        @Suppress("UNCHECKED_CAST") val irModuleFragment = psi2ir.generateModuleFragment(psi2irContext, files as Collection<KtFile>)
         JvmBackendFacade.doGenerateFilesInternal(state, errorHandler, irModuleFragment, psi2irContext, phaseConfig)
     }
 

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/codegen/IrInlineCodegen.kt

@@ -96,7 +96,7 @@ class IrInlineCodegen(
 
     private fun rememberClosure(irReference: IrFunctionReference, type: Type, parameter: ValueParameterDescriptor): LambdaInfo {
         //assert(InlineUtil.isInlinableParameterExpression(ktLambda)) { "Couldn't find inline expression in ${expression.text}" }
-        val expression = irReference.symbol.owner as IrFunction
+        val expression = irReference.symbol.owner
         return IrExpressionLambdaImpl(
             irReference, expression, typeMapper, parameter.isCrossinline, false/*TODO*/,
             parameter.type.isExtensionFunctionType

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/descriptors/SharedVariablesManager.kt

@@ -177,7 +177,7 @@ class JvmSharedVariablesManager(
             typeArgumentsCount = typeArgumentsCount,
             origin = SHARED_VARIABLE_CONSTRUCTOR_CALL_ORIGIN
         ).apply {
-            refConstructor.parentAsClass.typeParameters.mapIndexed { i, param ->
+            List(refConstructor.parentAsClass.typeParameters.size) { i ->
                 putTypeArgument(i, valueType)
             }
         }

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/MoveCompanionObjectFieldsLowering.kt

@@ -212,10 +212,10 @@ private class FieldReplacer(val replacementMap: Map<IrFieldSymbol, IrFieldSymbol
         } ?: super.visitGetField(expression)
 
     override fun visitSetField(expression: IrSetField): IrExpression =
-        replacementMap[expression.symbol]?.let { newSymbol ->
+        replacementMap[expression.symbol]?.let { _ ->
             IrSetFieldImpl(
                 expression.startOffset, expression.endOffset,
-                replacementMap[expression.symbol]!!,
+                replacementMap.getValue(expression.symbol),
                 /* receiver = */ null,
                 visitExpression(expression.value),
                 expression.type,

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/BranchingExpressionGenerator.kt

@@ -106,7 +106,6 @@ class BranchingExpressionGenerator(statementGenerator: StatementGenerator) : Sta
 
         // TODO relies on ControlFlowInformationProvider, get rid of it
         val isUsedAsExpression = get(BindingContext.USED_AS_EXPRESSION, expression) ?: false
-        val isExhaustive = expression.isExhaustiveWhen()
 
         val resultType = when {
             isUsedAsExpression -> inferredType.toIrType()

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/CallGenerator.kt

@@ -172,7 +172,7 @@ class CallGenerator(statementGenerator: StatementGenerator) : StatementGenerator
         val irType = descriptor.type.toIrType()
 
         return if (getMethodDescriptor == null) {
-            call.callReceiver.call { dispatchReceiverValue, extensionReceiverValue ->
+            call.callReceiver.call { dispatchReceiverValue, _ ->
                 val fieldSymbol = context.symbolTable.referenceField(descriptor.original)
                 IrGetFieldImpl(
                     startOffset, endOffset,

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/ReflectionReferencesGenerator.kt

@@ -156,6 +156,7 @@ class ReflectionReferencesGenerator(statementGenerator: StatementGenerator) : St
     private fun getFieldForPropertyReference(originalProperty: PropertyDescriptor) =
         // NB this is a hack, we really don't know if an arbitrary property has a backing field or not
         when {
+            @Suppress("DEPRECATION")
             originalProperty.isDelegated -> null
             originalProperty.getter != null -> null
             else -> context.symbolTable.referenceField(originalProperty)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/impl/IrLocalDelegatedPropertyImpl.kt

@@ -85,6 +85,7 @@ class IrLocalDelegatedPropertyImpl(
         descriptor.name, type, descriptor.isVar
     )
 
+    @Suppress("DEPRECATION")
     @Deprecated("Creates unbound symbol")
     constructor(
         startOffset: Int,

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/impl/IrPropertyImpl.kt

@@ -39,7 +39,7 @@ class IrPropertyImpl(
     override val isVar: Boolean = symbol.descriptor.isVar,
     override val isConst: Boolean = symbol.descriptor.isConst,
     override val isLateinit: Boolean = symbol.descriptor.isLateInit,
-    override val isDelegated: Boolean = symbol.descriptor.isDelegated,
+    @Suppress("DEPRECATION") override val isDelegated: Boolean = symbol.descriptor.isDelegated,
     override val isExternal: Boolean = symbol.descriptor.isEffectivelyExternal()
 ) : IrDeclarationBase(startOffset, endOffset, origin),
     IrProperty {
@@ -69,6 +69,7 @@ class IrPropertyImpl(
         isExternal = isExternal
     )
 
+    @Suppress("DEPRECATION")
     @Deprecated(message = "Don't use descriptor-based API for IrProperty", level = DeprecationLevel.WARNING)
     constructor(
         startOffset: Int,
@@ -86,6 +87,7 @@ class IrPropertyImpl(
         isExternal = descriptor.isEffectivelyExternal()
     )
 
+    @Suppress("DEPRECATION")
     @Deprecated(message = "Don't use descriptor-based API for IrProperty", level = DeprecationLevel.WARNING)
     constructor(
         startOffset: Int,
@@ -94,6 +96,7 @@ class IrPropertyImpl(
         descriptor: PropertyDescriptor
     ) : this(startOffset, endOffset, origin, descriptor.isDelegated, descriptor)
 
+    @Suppress("DEPRECATION")
     @Deprecated(message = "Don't use descriptor-based API for IrProperty", level = DeprecationLevel.WARNING)
     constructor(
         startOffset: Int,
@@ -106,6 +109,7 @@ class IrPropertyImpl(
         this.backingField = backingField
     }
 
+    @Suppress("DEPRECATION")
     @Deprecated(message = "Don't use descriptor-based API for IrProperty", level = DeprecationLevel.WARNING)
     constructor(
         startOffset: Int,

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/lazy/IrLazyProperty.kt

@@ -57,7 +57,7 @@ class IrLazyProperty(
         isVar = symbol.descriptor.isVar,
         isConst = symbol.descriptor.isConst,
         isLateinit = symbol.descriptor.isLateInit,
-        isDelegated = symbol.descriptor.isDelegated,
+        isDelegated = @Suppress("DEPRECATION") symbol.descriptor.isDelegated,
         isExternal = symbol.descriptor.isEffectivelyExternal(),
         stubGenerator = stubGenerator,
         typeTranslator = typeTranslator,

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/lazy/LazyScopedTypeParametersResolver.kt

@@ -33,6 +33,6 @@ class LazyScopedTypeParametersResolver(private val symbolTable: ReferenceSymbolT
             parent.typeParameters.firstOrNull {
                 it.descriptor == typeParameterDescriptor
             }?.symbol
-        } ?: null
+        }
     }
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/DeclarationStubGenerator.kt

@@ -93,7 +93,7 @@ class DeclarationStubGenerator(
         val origin = computeOrigin(descriptor)
         return symbolTable.declareProperty(
             UNDEFINED_OFFSET, UNDEFINED_OFFSET, origin, descriptor.original,
-            isDelegated = descriptor.isDelegated
+            isDelegated = @Suppress("DEPRECATION") descriptor.isDelegated
         ) {
             deserializer?.findDeserializedDeclaration(descriptor)
                 ?: IrLazyProperty(UNDEFINED_OFFSET, UNDEFINED_OFFSET, origin, it, this, typeTranslator, bindingContext)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/IrUtils.kt

@@ -62,7 +62,7 @@ fun IrMemberAccessExpression.getArguments(): List<Pair<ParameterDescriptor, IrEx
  */
 fun IrFunctionAccessExpression.getArgumentsWithSymbols(): List<Pair<IrValueParameterSymbol, IrExpression>> {
     val res = mutableListOf<Pair<IrValueParameterSymbol, IrExpression>>()
-    val irFunction = symbol.owner as IrFunction
+    val irFunction = symbol.owner
 
     dispatchReceiver?.let {
         res += (irFunction.dispatchReceiverParameter!!.symbol to it)
@@ -347,6 +347,7 @@ fun IrDeclaration.isEffectivelyExternal(): Boolean {
 inline fun <reified T : IrDeclaration> IrDeclarationContainer.findDeclaration(predicate: (T) -> Boolean): T? =
     declarations.find { it is T && predicate(it) } as? T
 
+@Suppress("UNCHECKED_CAST")
 inline fun <reified T : IrDeclaration> IrDeclarationContainer.filterDeclarations(predicate: (T) -> Boolean): List<T> =
     declarations.filter { it is T && predicate(it) } as List<T>
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/SymbolTable.kt

@@ -334,7 +334,7 @@ open class SymbolTable : ReferenceSymbolTable {
         endOffset: Int,
         origin: IrDeclarationOrigin,
         descriptor: PropertyDescriptor,
-        isDelegated: Boolean = descriptor.isDelegated,
+        @Suppress("DEPRECATION") isDelegated: Boolean = descriptor.isDelegated,
         propertyFactory: (IrPropertySymbol) -> IrProperty = { symbol ->
             IrPropertyImpl(startOffset, endOffset, origin, symbol, isDelegated = isDelegated).apply {
                 metadata = MetadataSource.Property(symbol.descriptor)

compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrModuleDeserializer.kt

@@ -166,7 +166,7 @@ abstract class IrModuleDeserializer(
     }
 
     private fun deserializeSyntheticBody(proto: KotlinIr.IrSyntheticBody, start: Int, end: Int): IrSyntheticBody {
-        val kind = when (proto.kind) {
+        val kind = when (proto.kind!!) {
             KotlinIr.IrSyntheticBodyKind.ENUM_VALUES -> IrSyntheticBodyKind.ENUM_VALUES
             KotlinIr.IrSyntheticBodyKind.ENUM_VALUEOF -> IrSyntheticBodyKind.ENUM_VALUEOF
         }
@@ -652,7 +652,7 @@ abstract class IrModuleDeserializer(
     }
 
     private fun deserializeConst(proto: KotlinIr.IrConst, start: Int, end: Int, type: IrType): IrExpression =
-        when (proto.valueCase) {
+        when (proto.valueCase!!) {
             NULL
             -> IrConstImpl.constNull(start, end, type)
             BOOLEAN
@@ -678,7 +678,7 @@ abstract class IrModuleDeserializer(
         }
 
     private fun deserializeOperation(proto: KotlinIr.IrOperation, start: Int, end: Int, type: IrType): IrExpression =
-        when (proto.operationCase) {
+        when (proto.operationCase!!) {
             BLOCK
             -> deserializeBlock(proto.block, start, end, type)
             BREAK
@@ -766,11 +766,12 @@ abstract class IrModuleDeserializer(
         val name = deserializeName(proto.name)
         val variance = deserializeIrTypeVariance(proto.variance)
 
-        val parameter = symbolTable.declareGlobalTypeParameter(UNDEFINED_OFFSET, UNDEFINED_OFFSET, irrelevantOrigin,
-            symbol.descriptor, { symbol ->
-                IrTypeParameterImpl(start, end, origin, symbol, name, proto.index, proto.isReified, variance)
-            }
-        )
+        val parameter = symbolTable.declareGlobalTypeParameter(
+            UNDEFINED_OFFSET, UNDEFINED_OFFSET, irrelevantOrigin,
+            symbol.descriptor
+        ) {
+            IrTypeParameterImpl(start, end, origin, it, name, proto.index, proto.isReified, variance)
+        }
 
         val superTypes = proto.superTypeList.map { deserializeIrType(it) }
         parameter.superTypes.addAll(superTypes)
@@ -1162,7 +1163,7 @@ abstract class IrModuleDeserializer(
 
         val declarator = proto.declarator
 
-        val declaration: IrDeclaration = when (declarator.declaratorCase) {
+        val declaration: IrDeclaration = when (declarator.declaratorCase!!) {
             IR_ANONYMOUS_INIT
             -> deserializeIrAnonymousInit(declarator.irAnonymousInit, start, end, origin)
             IR_CONSTRUCTOR

compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrModuleSerializer.kt

@@ -967,7 +967,7 @@ open class IrModuleSerializer(
     }
 
     private fun serializeIrProperty(property: IrProperty): KotlinIr.IrProperty {
-        val index = declarationTable.uniqIdByDeclaration(property)
+        declarationTable.uniqIdByDeclaration(property)
 
         val proto = KotlinIr.IrProperty.newBuilder()
             .setIsDelegated(property.isDelegated)

compiler/light-classes/src/org/jetbrains/kotlin/asJava/LightClassUtil.kt

@@ -133,7 +133,6 @@ object LightClassUtil {
                     .filter { it.kotlinOrigin === declaration }
 
     private fun getWrappingClass(declaration: KtDeclaration): PsiClass? {
-        var declaration = declaration
         if (declaration is KtParameter) {
             val constructorClass = KtPsiUtil.getClassIfParameterIsProperty(declaration)
             if (constructorClass != null) {
@@ -141,15 +140,16 @@ object LightClassUtil {
             }
         }
 
-        if (declaration is KtPropertyAccessor) {
-            declaration = declaration.property
+        var ktDeclaration = declaration
+        if (ktDeclaration is KtPropertyAccessor) {
+            ktDeclaration = ktDeclaration.property
         }
 
-        if (declaration is KtConstructor<*>) {
-            return declaration.getContainingClassOrObject().toLightClass()
+        if (ktDeclaration is KtConstructor<*>) {
+            return ktDeclaration.getContainingClassOrObject().toLightClass()
         }
 
-        val parent = declaration.parent
+        val parent = ktDeclaration.parent
 
         if (parent is KtFile) {
             // top-level declaration

compiler/light-classes/src/org/jetbrains/kotlin/asJava/classes/ultraLightPsi.kt

@@ -474,7 +474,7 @@ open class KtUltraLightClass(classOrObject: KtClassOrObject, internal val suppor
     }
 
     private fun addReceiverParameter(callable: KtCallableDeclaration, method: KtUltraLightMethod) {
-        val receiver = callable.receiverTypeReference ?: return
+        if (callable.receiverTypeReference == null) return
         method.delegate.addParameter(KtUltraLightReceiverParameter(callable, support, method))
     }
 

compiler/light-classes/src/org/jetbrains/kotlin/asJava/elements/lightAnnotations.kt

@@ -103,8 +103,7 @@ class KtLightAnnotationForSourceEntry(
     }
 
     private fun getAttributeValue(name: String?, useDefault: Boolean): PsiAnnotationMemberValue? {
-        val name = name ?: "value"
-        val callEntry = getCallEntry(name) ?: return null
+        val callEntry = getCallEntry(name ?: "value") ?: return null
 
         val valueArgument = callEntry.value.arguments.firstOrNull()
         if (valueArgument != null) {
@@ -341,7 +340,7 @@ private fun KtElement.getResolvedCall(): ResolvedCall<out CallableDescriptor>? {
 }
 
 fun convertToLightAnnotationMemberValue(lightParent: PsiElement, argument: KtExpression): PsiAnnotationMemberValue {
-    val argument = unwrapCall(argument)
+    @Suppress("NAME_SHADOWING") val argument = unwrapCall(argument)
     when (argument) {
         is KtClassLiteralExpression -> {
             return KtLightPsiClassObjectAccessExpression(argument, lightParent)
@@ -395,7 +394,7 @@ private fun unwrapCall(callee: KtExpression): KtExpression = when (callee) {
 }
 
 private fun getAnnotationName(callee: KtExpression): String? {
-    val callee = unwrapCall(callee)
+    @Suppress("NAME_SHADOWING") val callee = unwrapCall(callee)
     val resultingDescriptor = callee.getResolvedCall()?.resultingDescriptor
     if (resultingDescriptor is ClassConstructorDescriptor) {
         val ktClass = resultingDescriptor.constructedClass.source.getPsi() as? KtClass

compiler/psi/src/org/jetbrains/kotlin/kdoc/parser/KDocKnownTag.kt

@@ -16,8 +16,6 @@
 
 package org.jetbrains.kotlin.kdoc.parser
 
-import com.intellij.openapi.util.text.StringUtil
-
 enum class KDocKnownTag(val isReferenceRequired: Boolean, val isSectionStart: Boolean) {
     AUTHOR(false, false),
     THROWS(true, false),
@@ -35,12 +33,11 @@ enum class KDocKnownTag(val isReferenceRequired: Boolean, val isSectionStart: Bo
 
     companion object {
         fun findByTagName(tagName: CharSequence): KDocKnownTag? {
-            var tagName = tagName
-            if (StringUtil.startsWith(tagName, "@")) {
-                tagName = tagName.subSequence(1, tagName.length)
-            }
+            val name = if (tagName.startsWith('@')) {
+                tagName.subSequence(1, tagName.length)
+            } else tagName
             try {
-                return valueOf(tagName.toString().toUpperCase())
+                return valueOf(name.toString().toUpperCase())
             } catch (ignored: IllegalArgumentException) {
             }
 

compiler/psi/src/org/jetbrains/kotlin/psi/EditCommaSeparatedListHelper.kt

@@ -28,6 +28,7 @@ object EditCommaSeparatedListHelper {
         return addItemBefore(list, allItems, item, null, prefix)
     }
 
+    @Suppress("UNCHECKED_CAST")
     @JvmOverloads
     fun <TItem : KtElement> addItemAfter(
         list: KtElement,

compiler/psi/src/org/jetbrains/kotlin/psi/KtPsiFactory.kt

@@ -292,6 +292,7 @@ class KtPsiFactory @JvmOverloads constructor(private val project: Project, val m
         val file = createFile(text)
         val declarations = file.declarations
         assert(declarations.size == 1) { "${declarations.size} declarations in $text" }
+        @Suppress("UNCHECKED_CAST")
         return declarations.first() as TDeclaration
     }
 

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/components/AbstractTypeCheckerContextForConstraintSystem.kt

@@ -8,7 +8,6 @@ package org.jetbrains.kotlin.resolve.calls.inference.components
 import org.jetbrains.kotlin.types.AbstractNullabilityChecker
 import org.jetbrains.kotlin.types.AbstractTypeChecker
 import org.jetbrains.kotlin.types.AbstractTypeCheckerContext
-import org.jetbrains.kotlin.types.checker.*
 import org.jetbrains.kotlin.types.model.*
 
 abstract class AbstractTypeCheckerContextForConstraintSystem : AbstractTypeCheckerContext(), TypeSystemInferenceExtensionContext {
@@ -86,9 +85,9 @@ abstract class AbstractTypeCheckerContextForConstraintSystem : AbstractTypeCheck
     // extract type variable only from type like Captured(out T)
     private fun extractTypeVariableForSubtype(type: KotlinTypeMarker): KotlinTypeMarker? {
 
-        val type = type.asSimpleType()?.asCapturedType() ?: return null
+        val typeMarker = type.asSimpleType()?.asCapturedType() ?: return null
 
-        val projection = type.typeConstructorProjection()
+        val projection = typeMarker.typeConstructorProjection()
         return if (projection.getVariance() == TypeVariance.OUT)
             projection.getType().takeIf { it is SimpleTypeMarker && isMyTypeVariable(it) }?.asSimpleType()
         else

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/components/SimpleConstraintSystemImpl.kt

@@ -21,7 +21,6 @@ import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
 import org.jetbrains.kotlin.resolve.calls.components.ClassicTypeSystemContextForCS
 import org.jetbrains.kotlin.resolve.calls.inference.ConstraintSystemBuilder
 import org.jetbrains.kotlin.resolve.calls.inference.model.NewConstraintSystemImpl
-import org.jetbrains.kotlin.resolve.calls.inference.model.SimpleConstraintSystemConstraintPosition
 import org.jetbrains.kotlin.resolve.calls.inference.model.TypeVariableFromCallableDescriptor
 import org.jetbrains.kotlin.resolve.calls.inference.substitute
 import org.jetbrains.kotlin.resolve.calls.results.SimpleConstraintSystem
@@ -52,7 +51,12 @@ class SimpleConstraintSystemImpl(constraintInjector: ConstraintInjector, builtIn
     }
 
     override fun addSubtypeConstraint(subType: UnwrappedType, superType: UnwrappedType) {
-        csBuilder.addSubtypeConstraint(subType, superType, SimpleConstraintSystemConstraintPosition)
+        csBuilder.addSubtypeConstraint(
+            subType,
+            superType,
+            @Suppress("DEPRECATION")
+            org.jetbrains.kotlin.resolve.calls.inference.model.SimpleConstraintSystemConstraintPosition
+        )
     }
 
     override fun hasContradiction() = csBuilder.hasContradiction

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/results/OverloadingConflictResolver.kt

@@ -216,7 +216,7 @@ open class OverloadingConflictResolver<C : Any>(
             }
         }
         if (result == null) return null
-        if (any { it != result && isNotWorse(it, result!!) }) {
+        if (any { it != result && isNotWorse(it, result) }) {
             return null
         }
         return result

compiler/resolution/src/org/jetbrains/kotlin/resolve/scopes/LexicalScopeStorage.kt

@@ -121,6 +121,7 @@ abstract class LexicalScopeStorage(
         val result = ArrayList<TDescriptor>(1)
         var rest: IntList? = this
         do {
+            @Suppress("UNCHECKED_CAST")
             result.add(rest!!.last.descriptorByIndex() as TDescriptor)
             rest = rest.prev
         } while (rest != null)

compiler/tests-common/tests/org/jetbrains/kotlin/codegen/AbstractCheckLocalVariablesTableTest.kt

@@ -48,7 +48,7 @@ abstract class AbstractCheckLocalVariablesTableTest : CodegenTestCase() {
             val pathsString = outputFiles.joinToString { it.relativePath }
             assertNotNull("Couldn't find class file for pattern $classFileRegex in: $pathsString", outputFile)
 
-            val actualLocalVariables = readLocalVariable(ClassReader(outputFile!!.asByteArray()), methodName)
+            val actualLocalVariables = readLocalVariable(ClassReader(outputFile.asByteArray()), methodName)
 
             doCompare(wholeFile, files.single().content, actualLocalVariables)
         } catch (e: Throwable) {

compiler/tests-java8/tests/org/jetbrains/kotlin/serialization/builtins/AdditionalBuiltInsMembersSignatureListsTest.kt

@@ -59,10 +59,8 @@ class AdditionalBuiltInsMembersSignatureListsTest : KotlinTestWithEnvironment()
 
             val lateJdkSignatures = LATE_JDK_SIGNATURES[internalName] ?: emptySet()
 
-            jvmDescriptors.forEach {
-                jvmDescriptor ->
-
-                if (jvmDescriptor in lateJdkSignatures) return@forEach
+            for (jvmDescriptor in jvmDescriptors) {
+                if (jvmDescriptor in lateJdkSignatures) continue
 
                 val stringName = jvmDescriptor.split("(")[0]
                 val functions =

compiler/tests/org/jetbrains/kotlin/codegen/CustomScriptCodegenTest.kt

@@ -78,9 +78,11 @@ class CustomScriptCodegenTest : CodegenTestCase() {
 
 }
 
+@Suppress("UNCHECKED_CAST")
 private fun Class<*>.safeGetAnnotation(ann: KClass<out Annotation>): Annotation? =
     getAnnotation(classLoader.loadClass(ann.qualifiedName) as Class<Annotation>)
 
+@Suppress("UNCHECKED_CAST")
 private fun java.lang.reflect.Constructor<*>.safeGetAnnotation(ann: KClass<out Annotation>): Annotation? =
     getAnnotation(this.declaringClass.classLoader.loadClass(ann.qualifiedName) as Class<Annotation>)
 

compiler/tests/org/jetbrains/kotlin/daemon/CompilerDaemonTest.kt

@@ -579,11 +579,11 @@ class CompilerDaemonTest : KotlinIntegrationTestBase() {
                             ParallelStartParams.performCompilation -> {
                                 val jar = tmpdir.absolutePath + File.separator + "hello.$threadNo.jar"
                                 KotlinCompilerClient.compile(
-                                        compileServiceSession!!.compileService,
-                                        compileServiceSession.sessionId,
-                                        CompileService.TargetPlatform.JVM,
-                                        arrayOf(File(getHelloAppBaseDir(), "hello.kt").absolutePath, "-d", jar),
-                                        PrintingMessageCollector(PrintStream(outStreams[threadNo]), MessageRenderer.WITHOUT_PATHS, true))
+                                    compileServiceSession.compileService,
+                                    compileServiceSession.sessionId,
+                                    CompileService.TargetPlatform.JVM,
+                                    arrayOf(File(getHelloAppBaseDir(), "hello.kt").absolutePath, "-d", jar),
+                                    PrintingMessageCollector(PrintStream(outStreams[threadNo]), MessageRenderer.WITHOUT_PATHS, true))
                             }
                             else -> 0 // compilation skipped, assuming - successful
                         }

compiler/tests/org/jetbrains/kotlin/jvm/compiler/KotlinClassFinderTest.kt

@@ -60,10 +60,10 @@ class KotlinClassFinderTest : KotlinTestWithEnvironmentManagement() {
         assertNotNull(psiClass, "Psi class not found for $className")
         assertTrue(psiClass !is KtLightClass, "Kotlin light classes are not not expected")
 
-        val binaryClass = VirtualFileFinder.SERVICE.getInstance(project).findKotlinClass(JavaClassImpl(psiClass!!))
+        val binaryClass = VirtualFileFinder.SERVICE.getInstance(project).findKotlinClass(JavaClassImpl(psiClass))
         assertNotNull(binaryClass, "No binary class for $className")
 
-        assertEquals("test/A.B.C", binaryClass?.classId?.toString())
+        assertEquals("test/A.B.C", binaryClass.classId.toString())
     }
 
     private fun createEnvironment(tmpdir: File?): KotlinCoreEnvironment {

compiler/tests/org/jetbrains/kotlin/jvm/compiler/KotlinJavacBasedClassFinderTest.kt

@@ -66,10 +66,10 @@ class KotlinJavacBasedClassFinderTest : KotlinTestWithEnvironmentManagement() {
         val found = classFinder.findClass(classId)
         assertNotNull(found, "Class not found for $className")
 
-        val binaryClass = VirtualFileFinder.SERVICE.getInstance(project).findKotlinClass(found!!)
+        val binaryClass = VirtualFileFinder.SERVICE.getInstance(project).findKotlinClass(found)
         assertNotNull(binaryClass, "No binary class for $className")
 
-        assertEquals("test/A.B.C", binaryClass?.classId?.toString())
+        assertEquals("test/A.B.C", binaryClass.classId.toString())
     }
 
     private fun createClassFinder(project: Project) = JavacBasedClassFinder().apply {

compiler/tests/org/jetbrains/kotlin/serialization/AbstractVersionRequirementTest.kt

@@ -37,8 +37,8 @@ abstract class AbstractVersionRequirementTest : TestCaseWithTmpdir() {
             val descriptor = module.findUnambiguousDescriptorByFqName(fqName)
 
             val requirement = when (descriptor) {
-                is DeserializedMemberDescriptor -> descriptor.versionRequirements.single()
-                is DeserializedClassDescriptor -> descriptor.versionRequirements.single()
+                is DeserializedMemberDescriptor -> descriptor.versionRequirements.singleOrNull()
+                is DeserializedClassDescriptor -> descriptor.versionRequirements.singleOrNull()
                 else -> throw AssertionError("Unknown descriptor: $descriptor")
             } ?: throw AssertionError("No VersionRequirement for $descriptor")
 

compiler/tests/org/jetbrains/kotlin/types/AbstractTypeBindingTest.kt

@@ -40,7 +40,7 @@ abstract class AbstractTypeBindingTest : KotlinTestWithEnvironment() {
 
         val analyzeResult = JvmResolveUtil.analyze(testKtFile, environment)
 
-        val testDeclaration = testKtFile.declarations.last()!! as KtCallableDeclaration
+        val testDeclaration = testKtFile.declarations.last() as KtCallableDeclaration
 
         val typeBinding = testDeclaration.createTypeBindingForReturnType(analyzeResult.bindingContext)
 

core/descriptors.runtime/src/kotlin/reflect/jvm/internal/structure/ReflectJavaTypeParameter.kt

@@ -31,6 +31,7 @@ class ReflectJavaTypeParameter(
             return bounds
         }
 
+    @Suppress("USELESS_CAST")
     override val element: AnnotatedElement?
         // TypeVariable is AnnotatedElement only in JDK8
         get() = typeVariable as? AnnotatedElement

core/descriptors/src/org/jetbrains/kotlin/types/checker/ClassicTypeSystemContext.kt

@@ -404,6 +404,7 @@ interface ClassicTypeSystemContext : TypeSystemInferenceExtensionContext {
 
     override fun SimpleTypeMarker.replaceArguments(newArguments: List<TypeArgumentMarker>): SimpleTypeMarker {
         require(this is SimpleType, this::errorMessage)
+        @Suppress("UNCHECKED_CAST")
         return this.replace(newArguments as List<TypeProjection>)
     }
 

core/descriptors/src/org/jetbrains/kotlin/types/checker/NewKotlinTypeChecker.kt

@@ -137,6 +137,7 @@ object NewKotlinTypeChecker : KotlinTypeChecker {
         constructor: TypeConstructor
     ): List<SimpleType> {
         return AbstractTypeChecker.run {
+            @Suppress("UNCHECKED_CAST")
             findCorrespondingSupertypes(baseType, constructor) as List<SimpleType>
         }
     }

core/script.runtime/src/kotlin/script/experimental/location/scriptLocation_deprecated.kt

@@ -21,5 +21,5 @@ enum class ScriptExpectedLocation {
 @Target(AnnotationTarget.CLASS)
 @Retention(AnnotationRetention.RUNTIME)
 annotation class ScriptExpectedLocations(
-    val value: Array<ScriptExpectedLocation> = [ScriptExpectedLocation.SourcesOnly, ScriptExpectedLocation.TestsOnly]
+    @Suppress("DEPRECATION") val value: Array<ScriptExpectedLocation> = [ScriptExpectedLocation.SourcesOnly, ScriptExpectedLocation.TestsOnly]
 )

core/script.runtime/src/kotlin/script/templates/annotations_deprecated.kt

@@ -19,5 +19,5 @@ open class ScriptTemplateAdditionalCompilerArgumentsProvider(val arguments: Iter
 @Retention(AnnotationRetention.RUNTIME)
 annotation class ScriptTemplateAdditionalCompilerArguments(
     val arguments: Array<String> = [],
-    val provider: KClass<out ScriptTemplateAdditionalCompilerArgumentsProvider> = ScriptTemplateAdditionalCompilerArgumentsProvider::class
+    @Suppress("DEPRECATION") val provider: KClass<out ScriptTemplateAdditionalCompilerArgumentsProvider> = ScriptTemplateAdditionalCompilerArgumentsProvider::class
 )

generators/builtins/progressions.kt

@@ -47,7 +47,6 @@ class GenerateProgressions(out: PrintWriter) : BuiltInsSourceGenerator(out) {
                 "        if (isEmpty()) -1 else (31 * (31 * first + last) + step)"
             LONG ->
                 "        if (isEmpty()) -1 else (31 * (31 * ${hashLong("first")} + ${hashLong("last")}) + ${hashLong("step")}).toInt()"
-            else -> throw IllegalArgumentException()
         }
 
         out.println(

generators/builtins/unsignedTypes.kt

@@ -371,7 +371,6 @@ class UnsignedTypeGenerator(val type: UnsignedType, out: PrintWriter) : BuiltIns
             UnsignedType.UBYTE, UnsignedType.USHORT -> out.println("toInt().toString()")
             UnsignedType.UINT -> out.println("toLong().toString()")
             UnsignedType.ULONG -> out.println("ulongToString(data)")
-            else -> error(type)
         }
 
         out.println()

idea/formatter/src/org/jetbrains/kotlin/idea/formatter/SyntheticKotlinBlock.kt

@@ -60,13 +60,11 @@ class SyntheticKotlinBlock(
         }
 
         val textRange = getTextRange()
-        if (treeNode != null) {
-            val psi = treeNode.psi
-            if (psi != null) {
-                val file = psi.containingFile
-                if (file != null) {
-                    return file.text!!.subSequence(textRange.startOffset, textRange.endOffset).toString() + " " + textRange
-                }
+        val psi = treeNode.psi
+        if (psi != null) {
+            val file = psi.containingFile
+            if (file != null) {
+                return file.text!!.subSequence(textRange.startOffset, textRange.endOffset).toString() + " " + textRange
             }
         }
 

idea/ide-common/src/org/jetbrains/kotlin/idea/util/psi/patternMatching/KotlinPsiUnifier.kt

@@ -199,8 +199,8 @@ class KotlinPsiUnifier(
                     s and when {
                         arg1 == arg2 -> MATCHED
                         arg1 == null || arg2 == null -> UNMATCHED
-                        else -> (arg1.arguments.asSequence().zip(arg2.arguments.asSequence())).fold(MATCHED) { s, p ->
-                            s and matchArguments(p.first, p.second)
+                        else -> (arg1.arguments.asSequence().zip(arg2.arguments.asSequence())).fold(MATCHED) { status, pair ->
+                            status and matchArguments(pair.first, pair.second)
                         }
                     }
                 }
@@ -711,7 +711,7 @@ class KotlinPsiUnifier(
                     null
             }
             if (status == UNMATCHED) {
-                declarationPatternsToTargets.removeValue(desc1, desc2)
+                declarationPatternsToTargets.remove(desc1, desc2)
             }
 
             return status

idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/lightClasses/LazyLightClassDataHolder.kt

@@ -110,7 +110,7 @@ sealed class LazyLightClassDataHolder(
             return dummyDelegate!!.fields.map { dummyField ->
                 val fieldOrigin = KtLightFieldImpl.getOrigin(dummyField)
 
-                val fieldName = dummyField.name!!
+                val fieldName = dummyField.name
                 KtLightFieldImpl.lazy(dummyField, fieldOrigin, containingClass) {
                     clsDelegate.findFieldByName(fieldName, false).assertMatches(dummyField, containingClass)
                 }

idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/lightClasses/LightMemberOriginForCompiledElement.kt

@@ -60,7 +60,7 @@ data class LightMemberOriginForCompiledField(val psiField: PsiField, val file: K
 
     override val originalElement: KtDeclaration? by lazyPub {
         val desc = MapPsiToAsmDesc.typeDesc(psiField.type)
-        val signature = MemberSignature.fromFieldNameAndDesc(psiField.name!!, desc)
+        val signature = MemberSignature.fromFieldNameAndDesc(psiField.name, desc)
         findDeclarationInCompiledFile(file, psiField, signature)
     }
 }

idea/idea-analysis/src/org/jetbrains/kotlin/idea/inspections/AbstractApplicabilityBasedInspection.kt

@@ -33,6 +33,7 @@ abstract class AbstractApplicabilityBasedInspection<TElement: KtElement>(
                     super.visitKtElement(element)
 
                     if (!elementType.isInstance(element) || element.textLength == 0) return
+                    @Suppress("UNCHECKED_CAST")
                     visitTargetElement(element as TElement, holder, isOnTheFly)
                 }
             }

idea/idea-analysis/src/org/jetbrains/kotlin/idea/inspections/IntentionBasedInspection.kt

@@ -175,7 +175,11 @@ abstract class IntentionBasedInspection<TElement : PsiElement> private construct
 
         override fun isAvailable(project: Project, file: PsiFile, startElement: PsiElement, endElement: PsiElement): Boolean {
             assert(startElement == endElement)
-            return intention.applicabilityRange(startElement as TElement) != null && additionalChecker(startElement, this@IntentionBasedInspection)
+            @Suppress("UNCHECKED_CAST")
+            return intention.applicabilityRange(startElement as TElement) != null && additionalChecker(
+                startElement,
+                this@IntentionBasedInspection
+            )
         }
 
         override fun invoke(project: Project, editor: Editor?, file: PsiFile?) {
@@ -190,6 +194,7 @@ abstract class IntentionBasedInspection<TElement : PsiElement> private construct
 
             val editor = startElement.findExistingEditor()
             editor?.caretModel?.moveToOffset(startElement.textOffset)
+            @Suppress("UNCHECKED_CAST")
             intention.applyTo(startElement as TElement, editor)
         }
     }

idea/idea-analysis/src/org/jetbrains/kotlin/idea/inspections/KotlinUniversalQuickFix.kt

@@ -22,6 +22,7 @@ import com.intellij.codeInspection.ProblemDescriptor
 import com.intellij.openapi.project.Project
 
 interface KotlinUniversalQuickFix : IntentionAction, LocalQuickFix {
+    @JvmDefault
     override fun getName() = text
 
     override fun applyFix(project: Project, descriptor: ProblemDescriptor) {

idea/idea-analysis/src/org/jetbrains/kotlin/idea/references/SyntheticPropertyAccessorReference.kt

@@ -136,7 +136,7 @@ sealed class SyntheticPropertyAccessorReference(expression: KtNameReferenceExpre
             val fullExpression = expression.getQualifiedExpressionForSelectorOrThis()
             fullExpression.getAssignmentByLHS()?.let { assignment ->
                 val rhs = assignment.right ?: return expression
-                val operationToken = assignment.operationToken as? KtSingleValueToken
+                val operationToken = assignment.operationToken as? KtSingleValueToken ?: return expression
                 val counterpartOp = OperatorConventions.ASSIGNMENT_OPERATION_COUNTERPARTS[operationToken]
                 val setterArgument = if (counterpartOp != null) {
                     val getterCall = if (getter) fullExpression.createCall(psiFactory, newGetterName) else fullExpression

idea/idea-analysis/src/org/jetbrains/kotlin/idea/stubindex/IndexUtils.kt

@@ -121,4 +121,4 @@ fun indexInternals(stub: KotlinCallableStubBase<*>, sink: IndexSink) {
 }
 
 private val KotlinStubWithFqName<*>.modifierList: KotlinModifierListStub?
-    get() = findChildStubByType(KtStubElementTypes.MODIFIER_LIST) as? KotlinModifierListStub
+    get() = findChildStubByType(KtStubElementTypes.MODIFIER_LIST)

idea/idea-analysis/src/org/jetbrains/kotlin/idea/stubindex/KotlinTypeAliasByExpansionShortNameIndex.kt

@@ -27,7 +27,7 @@ class KotlinTypeAliasByExpansionShortNameIndex : StringStubIndexExtension<KtType
     override fun getKey(): StubIndexKey<String, KtTypeAlias> = KEY
 
     override fun get(key: String, project: Project, scope: GlobalSearchScope) =
-            StubIndex.getElements(KEY, key, project, scope, KtTypeAlias::class.java)!!
+        StubIndex.getElements(KEY, key, project, scope, KtTypeAlias::class.java)
 
     companion object {
         val KEY = KotlinIndexUtil.createIndexKey(KotlinTypeAliasByExpansionShortNameIndex::class.java)

idea/idea-analysis/src/org/jetbrains/kotlin/idea/util/ApplicationUtils.kt

@@ -40,7 +40,7 @@ fun <T> Project.executeWriteCommand(name: String, groupId: Any? = null, command:
 }
 
 fun <T> Project.executeCommand(name: String, groupId: Any? = null, command: () -> T): T {
-    var result: T = null as T
+    @Suppress("UNCHECKED_CAST") var result: T = null as T
     CommandProcessor.getInstance().executeCommand(this, { result = command() }, name, groupId)
     @Suppress("USELESS_CAST")
     return result as T

idea/idea-analysis/src/org/jetbrains/kotlin/idea/util/dumbUtils.kt

@@ -26,7 +26,7 @@ fun <T> Project.runReadActionInSmartMode(action: () -> T): T {
 }
 
 fun <T> Project.runWithAlternativeResolveEnabled(action: () -> T): T {
-    var result: T = null as T
+    @Suppress("UNCHECKED_CAST") var result: T = null as T
     DumbService.getInstance(this).withAlternativeResolveEnabled { result = action() }
     @Suppress("USELESS_CAST")
     return result as T

idea/idea-android/idea-android-output-parser/src/org/jetbrains/kotlin/android/KotlinOutputParserHelper.kt

@@ -57,8 +57,8 @@ fun parse(lineText: String, reader: OutputLineReader, messages: MutableList<Mess
                 val column = if (matcher.groupCount() >= 2) matcher.group(2)?.toInt() ?: 1 else 1
 
                 if (line != null) {
-                    val position = SourceFilePosition(file, SourcePosition(line, column, column))
-                    return addMessage(Message(getMessageKind(severity), message.trim(), position), messages)
+                    val filePosition = SourceFilePosition(file, SourcePosition(line, column, column))
+                    return addMessage(Message(getMessageKind(severity), message.trim(), filePosition), messages)
                 }
             }
 

idea/idea-android/src/org/jetbrains/kotlin/android/configure/AndroidGradleModelFacade.kt

@@ -33,7 +33,7 @@ class AndroidGradleModelFacade : KotlinGradleModelFacade {
     }
 
     override fun getDependencyModules(ideModule: DataNode<ModuleData>, gradleIdeaProject: IdeaProject): Collection<DataNode<ModuleData>> {
-        val ideProject = ideModule.parent as DataNode<ProjectData>
+        @Suppress("UNCHECKED_CAST") val ideProject = ideModule.parent as DataNode<ProjectData>
         ExternalSystemApiUtil.find(ideModule, AndroidProjectKeys.JAVA_MODULE_MODEL)?.let { javaModuleModel ->
             val moduleNames = javaModuleModel.data.javaModuleDependencies.map { it.moduleName }.toHashSet()
             return findModulesByNames(moduleNames, gradleIdeaProject, ideProject)
@@ -43,6 +43,7 @@ class AndroidGradleModelFacade : KotlinGradleModelFacade {
             val projects = androidModel.data.mainArtifact.dependencies.projects
             val projectIds = libraries.mapNotNull { it.projectSafe } + projects
             return projectIds.mapNotNullTo(LinkedHashSet()) { projectId ->
+                @Suppress("UNCHECKED_CAST")
                 ExternalSystemApiUtil.findFirstRecursively(ideProject) {
                     (it.data as? ModuleData)?.id == projectId
                 } as DataNode<ModuleData>?

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/PackageDirectiveCompletion.kt

@@ -46,7 +46,7 @@ object PackageDirectiveCompletion {
         val prefixLength = parameters.offset - expression.textOffset
         val prefix = expression.text!!
         val prefixMatcher = PlainPrefixMatcher(prefix.substring(0, prefixLength))
-        val result = result.withPrefixMatcher(prefixMatcher)
+        val resultSet = result.withPrefixMatcher(prefixMatcher)
 
         val resolutionFacade = expression.getResolutionFacade()
 
@@ -57,7 +57,7 @@ object PackageDirectiveCompletion {
         for (variant in variants) {
             val lookupElement = lookupElementFactory.createLookupElement(variant)
             if (!lookupElement.lookupString.contains(DUMMY_IDENTIFIER)) {
-                result.addElement(lookupElement)
+                resultSet.addElement(lookupElement)
             }
         }
 

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/VariableOrParameterNameWithTypeCompletion.kt

@@ -123,8 +123,8 @@ class VariableOrParameterNameWithTypeCompletion(
                     val parameterType = descriptor.type
                     if (parameterType.isVisible(visibilityFilter)) {
                         val lookupElement = MyLookupElement.create(name, ArbitraryType(parameterType), withType, lookupElementFactory)!!
-                        val (count, name) = lookupElementToCount[lookupElement] ?: Pair(0, name)
-                        lookupElementToCount[lookupElement] = Pair(count + 1, name)
+                        val (count, s) = lookupElementToCount[lookupElement] ?: Pair(0, name)
+                        lookupElementToCount[lookupElement] = Pair(count + 1, s)
                     }
                 }
             }

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/smart/LambdaItems.kt

@@ -84,22 +84,28 @@ object LambdaItems {
     }
 
     private fun createLookupElement(
-            functionType: KotlinType,
-            functionExpectedInfos: List<ExpectedInfo>,
-            signaturePresentation: LambdaSignatureTemplates.SignaturePresentation,
-            explicitParameterTypes: Boolean
+        functionType: KotlinType,
+        functionExpectedInfos: List<ExpectedInfo>,
+        signaturePresentation: LambdaSignatureTemplates.SignaturePresentation,
+        explicitParameterTypes: Boolean
     ): LookupElement {
         val lookupString = LambdaSignatureTemplates.lambdaPresentation(functionType, signaturePresentation)
         return LookupElementBuilder.create(lookupString)
-                .withInsertHandler({ context, lookupElement ->
-                                       val offset = context.startOffset
-                                       val placeholder = "{}"
-                                       context.document.replaceString(offset, context.tailOffset, placeholder)
-                                       val placeholderRange = TextRange(offset, offset + placeholder.length)
-                                       LambdaSignatureTemplates.insertTemplate(context, placeholderRange, functionType, explicitParameterTypes, signatureOnly = false)
-                                   })
-                .suppressAutoInsertion()
-                .assignSmartCompletionPriority(SmartCompletionItemPriority.LAMBDA)
-                .addTailAndNameSimilarity(functionExpectedInfos.filter { it.fuzzyType?.type == functionType })
+            .withInsertHandler { context, _ ->
+                val offset = context.startOffset
+                val placeholder = "{}"
+                context.document.replaceString(offset, context.tailOffset, placeholder)
+                val placeholderRange = TextRange(offset, offset + placeholder.length)
+                LambdaSignatureTemplates.insertTemplate(
+                    context,
+                    placeholderRange,
+                    functionType,
+                    explicitParameterTypes,
+                    signatureOnly = false
+                )
+            }
+            .suppressAutoInsertion()
+            .assignSmartCompletionPriority(SmartCompletionItemPriority.LAMBDA)
+            .addTailAndNameSimilarity(functionExpectedInfos.filter { it.fuzzyType?.type == functionType })
     }
 }

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/smart/LambdaSignatureItems.kt

@@ -64,9 +64,9 @@ object LambdaSignatureItems {
     }
 
     private fun createLookupElement(
-            functionType: KotlinType,
-            signaturePresentation: LambdaSignatureTemplates.SignaturePresentation,
-            explicitParameterTypes: Boolean
+        functionType: KotlinType,
+        signaturePresentation: LambdaSignatureTemplates.SignaturePresentation,
+        explicitParameterTypes: Boolean
     ): LookupElement {
         val lookupString = LambdaSignatureTemplates.signaturePresentation(functionType, signaturePresentation)
         val priority = if (explicitParameterTypes)
@@ -74,13 +74,19 @@ object LambdaSignatureItems {
         else
             SmartCompletionItemPriority.LAMBDA_SIGNATURE
         return LookupElementBuilder.create(lookupString)
-                .withInsertHandler({ context, lookupElement ->
-                                       val offset = context.startOffset
-                                       val placeholder = "{}"
-                                       context.document.replaceString(offset, context.tailOffset, placeholder)
-                                       LambdaSignatureTemplates.insertTemplate(context, TextRange(offset, offset + placeholder.length), functionType, explicitParameterTypes, signatureOnly = true)
-                                   })
-                .suppressAutoInsertion()
-                .assignSmartCompletionPriority(priority)
+            .withInsertHandler { context, _ ->
+                val offset = context.startOffset
+                val placeholder = "{}"
+                context.document.replaceString(offset, context.tailOffset, placeholder)
+                LambdaSignatureTemplates.insertTemplate(
+                    context,
+                    TextRange(offset, offset + placeholder.length),
+                    functionType,
+                    explicitParameterTypes,
+                    signatureOnly = true
+                )
+            }
+            .suppressAutoInsertion()
+            .assignSmartCompletionPriority(priority)
     }
 }