Do not write version requirements for InlineClasses

Language feature InlineClasses is enabled since 1.3. The current lowest
supported language version is 1.4, so any compiler that can read
binaries produced by the current compiler also supports inline classes,
which means that the version requirement is not needed anymore.

No issue reported because it's mostly not a user-visible change. The
main effect is that it reduces differences in metadata between K1 and
K2, because K2 never supported writing this version requirement properly
due to the TODO in `hasInlineClassTypesInSignature`.

compiler/fir/fir-serialization/src/org/jetbrains/kotlin/fir/serialization/FirElementSerializer.kt

@@ -277,8 +277,6 @@ class FirElementSerializer private constructor(
 
         extension.serializeClass(klass, builder, versionRequirementTable, this)
 
-        writeVersionRequirementForInlineClasses(klass, builder, versionRequirementTable)
-
         if (metDefinitelyNotNullType) {
             builder.addVersionRequirement(
                 writeLanguageVersionRequirement(LanguageFeature.DefinitelyNonNullableTypes, versionRequirementTable)
@@ -484,10 +482,6 @@ class FirElementSerializer private constructor(
                 builder.addVersionRequirement(writeVersionRequirementDependingOnCoroutinesVersion())
             }
 
-            if (property.hasInlineClassTypesInSignature()) {
-                builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.InlineClasses))
-            }
-
             if (local.metDefinitelyNotNullType) {
                 builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.DefinitelyNonNullableTypes))
             }
@@ -583,10 +577,6 @@ class FirElementSerializer private constructor(
                 builder.addVersionRequirement(writeVersionRequirementDependingOnCoroutinesVersion())
             }
 
-            if (function.hasInlineClassTypesInSignature()) {
-                builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.InlineClasses))
-            }
-
             if (local.metDefinitelyNotNullType) {
                 builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.DefinitelyNonNullableTypes))
             }
@@ -693,10 +683,6 @@ class FirElementSerializer private constructor(
                 builder.addVersionRequirement(writeVersionRequirementDependingOnCoroutinesVersion())
             }
 
-            if (constructor.hasInlineClassTypesInSignature()) {
-                builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.InlineClasses))
-            }
-
             if (local.metDefinitelyNotNullType) {
                 builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.DefinitelyNonNullableTypes))
             }
@@ -1076,28 +1062,11 @@ class FirElementSerializer private constructor(
 
     private fun useTypeTable(): Boolean = extension.shouldUseTypeTable()
 
-    private fun FirDeclaration.hasInlineClassTypesInSignature(): Boolean {
-        // TODO
-        return false
-    }
-
     private fun FirCallableDeclaration.isSuspendOrHasSuspendTypesInSignature(): Boolean {
         // TODO (types in signature)
         return this.isSuspend
     }
 
-    private fun writeVersionRequirementForInlineClasses(
-        klass: FirClass,
-        builder: ProtoBuf.Class.Builder,
-        versionRequirementTable: MutableVersionRequirementTable
-    ) {
-        if (klass !is FirRegularClass || !klass.isInline && !klass.hasInlineClassTypesInSignature()) return
-
-        builder.addVersionRequirement(
-            writeLanguageVersionRequirement(LanguageFeature.InlineClasses, versionRequirementTable)
-        )
-    }
-
     private fun MutableVersionRequirementTable.serializeVersionRequirements(container: FirAnnotationContainer): List<Int> =
         serializeVersionRequirements(container.annotations)
 

compiler/serialization/src/org/jetbrains/kotlin/serialization/DescriptorSerializer.kt

@@ -25,8 +25,10 @@ import org.jetbrains.kotlin.metadata.serialization.MutableTypeTable
 import org.jetbrains.kotlin.metadata.serialization.MutableVersionRequirementTable
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
-import org.jetbrains.kotlin.resolve.*
+import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.DescriptorUtils.isEnumEntry
+import org.jetbrains.kotlin.resolve.MemberComparator
+import org.jetbrains.kotlin.resolve.RequireKotlinConstants
 import org.jetbrains.kotlin.resolve.calls.components.isActualParameterWithAnyExpectedDefault
 import org.jetbrains.kotlin.resolve.constants.EnumValue
 import org.jetbrains.kotlin.resolve.constants.IntValue
@@ -35,13 +37,13 @@ import org.jetbrains.kotlin.resolve.constants.StringValue
 import org.jetbrains.kotlin.resolve.descriptorUtil.inlineClassRepresentation
 import org.jetbrains.kotlin.resolve.descriptorUtil.multiFieldValueClassRepresentation
 import org.jetbrains.kotlin.resolve.descriptorUtil.nonSourceAnnotations
+import org.jetbrains.kotlin.resolve.isValueClass
 import org.jetbrains.kotlin.serialization.deserialization.ProtoEnumFlags
 import org.jetbrains.kotlin.serialization.deserialization.descriptorVisibility
 import org.jetbrains.kotlin.serialization.deserialization.memberKind
 import org.jetbrains.kotlin.types.*
 import org.jetbrains.kotlin.types.extensions.TypeAttributeTranslators
 import org.jetbrains.kotlin.types.typeUtil.contains
-import org.jetbrains.kotlin.types.typeUtil.immediateSupertypes
 import org.jetbrains.kotlin.types.typeUtil.replaceAnnotations
 import java.util.*
 
@@ -193,8 +195,6 @@ class DescriptorSerializer private constructor(
 
         plugins.forEach { it.afterClass(classDescriptor, builder, versionRequirementTable, this, extension) }
 
-        writeVersionRequirementForInlineClasses(classDescriptor, builder, versionRequirementTable)
-
         if (metDefinitelyNotNullType) {
             builder.addVersionRequirement(
                 writeLanguageVersionRequirement(LanguageFeature.DefinitelyNonNullableTypes, versionRequirementTable)
@@ -207,28 +207,6 @@ class DescriptorSerializer private constructor(
         return builder
     }
 
-    private fun writeVersionRequirementForInlineClasses(
-        classDescriptor: ClassDescriptor,
-        builder: ProtoBuf.Class.Builder,
-        versionRequirementTable: MutableVersionRequirementTable
-    ) {
-        if (!classDescriptor.isInlineClass() && !classDescriptor.hasInlineClassTypesInSignature()) return
-
-        builder.addVersionRequirement(
-            writeLanguageVersionRequirement(LanguageFeature.InlineClasses, versionRequirementTable)
-        )
-    }
-
-    private fun ClassDescriptor.hasInlineClassTypesInSignature(): Boolean {
-        for (typeParameter in declaredTypeParameters) {
-            if (typeParameter.upperBounds.any { it.contains(UnwrappedType::isInlineClassType) }) return true
-        }
-
-        if (defaultType.immediateSupertypes().any { supertype -> supertype.contains(UnwrappedType::isInlineClassType) }) return true
-
-        return false
-    }
-
     fun propertyProto(descriptor: PropertyDescriptor): ProtoBuf.Property.Builder? {
         val builder = ProtoBuf.Property.newBuilder()
 
@@ -322,10 +300,6 @@ class DescriptorSerializer private constructor(
                 builder.addVersionRequirement(writeVersionRequirementDependingOnCoroutinesVersion())
             }
 
-            if (descriptor.hasInlineClassTypesInSignature()) {
-                builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.InlineClasses))
-            }
-
             if (local.metDefinitelyNotNullType) {
                 builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.DefinitelyNonNullableTypes))
             }
@@ -419,10 +393,6 @@ class DescriptorSerializer private constructor(
                 builder.addVersionRequirement(writeVersionRequirementDependingOnCoroutinesVersion())
             }
 
-            if (descriptor.hasInlineClassTypesInSignature()) {
-                builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.InlineClasses))
-            }
-
             if (local.metDefinitelyNotNullType) {
                 builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.DefinitelyNonNullableTypes))
             }
@@ -455,10 +425,6 @@ class DescriptorSerializer private constructor(
                 builder.addVersionRequirement(writeVersionRequirementDependingOnCoroutinesVersion())
             }
 
-            if (descriptor.hasInlineClassTypesInSignature()) {
-                builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.InlineClasses))
-            }
-
             if (local.metDefinitelyNotNullType) {
                 builder.addVersionRequirement(writeVersionRequirement(LanguageFeature.DefinitelyNonNullableTypes))
             }
@@ -480,10 +446,6 @@ class DescriptorSerializer private constructor(
         return allTypesFromSignature().any { type -> type.contains(UnwrappedType::isSuspendFunctionTypeOrSubtype) }
     }
 
-    private fun CallableMemberDescriptor.hasInlineClassTypesInSignature(): Boolean {
-        return allTypesFromSignature().any { type -> type.contains(UnwrappedType::isInlineClassType) }
-    }
-
     private fun CallableMemberDescriptor.allTypesFromSignature(): List<KotlinType> {
         return listOfNotNull(
             extensionReceiverParameter?.type,
@@ -760,9 +722,6 @@ class DescriptorSerializer private constructor(
         return writeLanguageVersionRequirement(languageFeature, this)
     }
 
-    private fun MutableVersionRequirementTable.writeCompilerVersionRequirement(major: Int, minor: Int, patch: Int): Int =
-        writeCompilerVersionRequirement(major, minor, patch, this)
-
     // Returns a list of indices into versionRequirementTable, or empty list if there's no @RequireKotlin on the descriptor
     private fun MutableVersionRequirementTable.serializeVersionRequirements(descriptor: DeclarationDescriptor): List<Int> =
         descriptor.annotations
@@ -925,17 +884,6 @@ class DescriptorSerializer private constructor(
             )
         }
 
-        fun writeCompilerVersionRequirement(
-            major: Int,
-            minor: Int,
-            patch: Int,
-            versionRequirementTable: MutableVersionRequirementTable
-        ): Int = writeVersionRequirement(
-            major, minor, patch,
-            ProtoBuf.VersionRequirement.VersionKind.COMPILER_VERSION,
-            versionRequirementTable
-        )
-
         fun writeVersionRequirement(
             major: Int,
             minor: Int,

compiler/testData/versionRequirement/inlineClassReturnTypeMangled.kt

@@ -5,11 +5,4 @@ inline class IC(val x: Int)
 class C {
     fun returnsInlineClassType(): IC = IC(42)
     val propertyOfInlineClassType: IC get() = IC(42)
-
-    @Suppress("INAPPLICABLE_JVM_NAME")
-    @JvmName("returnsInlineClassTypeJvmName")
-    fun returnsInlineClassTypeJvmName(): IC = IC(42)
 }
-
-fun returnsInlineClassType(): IC = IC(42)
-val propertyOfInlineClassType: IC get() = IC(42)

compiler/testData/versionRequirement/inlineClassesAndRelevantDeclarations13.kt

@@ -1,17 +0,0 @@
-package test
-
-inline class IC(val x: String)
-
-typealias ICAlias = IC
-
-class Ctor(ic: IC)
-
-fun simpleFun(f: IC) {}
-fun aliasedFun(f: ICAlias) {}
-
-val simpleProp: IC = IC("")
-
-fun result(r: List<Result<Any>?>) {}
-
-abstract class Foo : List<IC>
-interface Bar<T : IC>

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

@@ -227,21 +227,4 @@ abstract class AbstractVersionRequirementTest : TestCaseWithTmpdir() {
             )
         )
     }
-
-    fun testInlineClassesAndRelevantDeclarations13() {
-        doTest(
-            VersionRequirement.Version(1, 3), DeprecationLevel.ERROR, null, ProtoBuf.VersionRequirement.VersionKind.LANGUAGE_VERSION, null,
-            fqNamesWithRequirements = listOf(
-                "test.IC",
-                "test.Ctor.<init>",
-                "test.simpleFun",
-                "test.aliasedFun",
-                "test.simpleProp",
-                "test.result",
-                "test.Foo",
-                "test.Bar"
-            ),
-            shouldBeSingleRequirement = false
-        )
-    }
 }

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

@@ -112,8 +112,7 @@ class JvmVersionRequirementTest : AbstractVersionRequirementTest() {
 
     fun testInlineClassReturnTypeMangled() {
         // Class members returning inline class values are mangled,
-        // and have "since 1.4", "require 1.4.30" version requirement along with
+        // and have "language >= 1.4" and "compiler >= 1.4.30" version requirements.
-        // "since 1.3" version requirement for inline class in signature
         doTest(
             VersionRequirement.Version(1, 4, 0), DeprecationLevel.ERROR, null, LANGUAGE_VERSION, null,
             fqNamesWithRequirements = listOf(
@@ -126,36 +125,11 @@ class JvmVersionRequirementTest : AbstractVersionRequirementTest() {
         doTest(
             VersionRequirement.Version(1, 4, 30), DeprecationLevel.ERROR, null, COMPILER_VERSION, null,
             fqNamesWithRequirements = listOf(
-                "test.C.propertyOfInlineClassType",
                 "test.C.returnsInlineClassType",
-            ),
-            shouldBeSingleRequirement = false,
-            customLanguageVersion = LanguageVersion.KOTLIN_1_4
-        )
-        // Top-level functions and properties returning inline class values are NOT mangled,
-        // and have "since 1.3" version requirement for inline class in signature only.
-        doTest(
-            VersionRequirement.Version(1, 3, 0), DeprecationLevel.ERROR, null, LANGUAGE_VERSION, null,
-            fqNamesWithRequirements = listOf(
-                "test.propertyOfInlineClassType",
-                "test.returnsInlineClassType",
-            ),
-            shouldBeSingleRequirement = false,
-            customLanguageVersion = LanguageVersion.KOTLIN_1_4
-        )
-        // In Kotlin 1.3, all functions and properties returning inline class values are NOT mangled,
-        // and have "since 1.3" version requirement for inline class in signature only.
-        doTest(
-            VersionRequirement.Version(1, 3, 0), DeprecationLevel.ERROR, null, LANGUAGE_VERSION, null,
-            fqNamesWithRequirements = listOf(
-                "test.propertyOfInlineClassType",
                 "test.C.propertyOfInlineClassType",
-                "test.C.returnsInlineClassTypeJvmName",
-                "test.returnsInlineClassType",
-                "test.C.returnsInlineClassType"
             ),
-            shouldBeSingleRequirement = true,
+            customLanguageVersion = LanguageVersion.KOTLIN_1_4,
-            customLanguageVersion = LanguageVersion.KOTLIN_1_3
+            shouldBeSingleRequirement = false,
         )
     }
 

libraries/tools/kotlinp/testData/Annotations.txt

@@ -2,7 +2,6 @@
 // ------------------------------------------
 public final annotation class A : kotlin/Annotation {
 
-  // requires language version 1.3.0 (level=ERROR)
   // signature: <init>(ZCBSIFJDLkotlin/UInt;Lkotlin/UByte;Lkotlin/UShort;Lkotlin/ULong;Lkotlin/UInt;Lkotlin/UByte;Lkotlin/UShort;Lkotlin/ULong;[Z[C[B[S[I[F[J[DLjava/lang/String;Lkotlin/annotation/AnnotationTarget;Lkotlin/reflect/KClass;Lkotlin/reflect/KClass;LB;Lkotlin/Array;Lkotlin/Array;Lkotlin/Array;Lkotlin/Array;)V
   public constructor(z: kotlin/Boolean, c: kotlin/Char, b: kotlin/Byte, s: kotlin/Short, i: kotlin/Int, f: kotlin/Float, j: kotlin/Long, d: kotlin/Double, ui: kotlin/UInt, ub: kotlin/UByte, us: kotlin/UShort, ul: kotlin/ULong, ui_max: kotlin/UInt, ub_max: kotlin/UByte, us_max: kotlin/UShort, ul_max: kotlin/ULong, za: kotlin/BooleanArray, ca: kotlin/CharArray, ba: kotlin/ByteArray, sa: kotlin/ShortArray, ia: kotlin/IntArray, fa: kotlin/FloatArray, ja: kotlin/LongArray, da: kotlin/DoubleArray, str: kotlin/String, enum: kotlin/annotation/AnnotationTarget, klass: kotlin/reflect/KClass<*>, klass2: kotlin/reflect/KClass<*>, anno: B, stra: kotlin/Array<kotlin/String>, ka: kotlin/Array<kotlin/reflect/KClass<*>>, ea: kotlin/Array<kotlin/annotation/AnnotationTarget>, aa: kotlin/Array<B>)
 
@@ -98,56 +97,48 @@ public final annotation class A : kotlin/Annotation {
   public final val stra: kotlin/Array<kotlin/String>
     public final get
 
-  // requires language version 1.3.0 (level=ERROR)
   // requires compiler version 1.4.30 (level=ERROR)
   // requires language version 1.4.0 (level=ERROR)
   // getter: ub()B
   public final val ub: kotlin/UByte
     public final get
 
-  // requires language version 1.3.0 (level=ERROR)
   // requires compiler version 1.4.30 (level=ERROR)
   // requires language version 1.4.0 (level=ERROR)
   // getter: ub_max()B
   public final val ub_max: kotlin/UByte
     public final get
 
-  // requires language version 1.3.0 (level=ERROR)
   // requires compiler version 1.4.30 (level=ERROR)
   // requires language version 1.4.0 (level=ERROR)
   // getter: ui()I
   public final val ui: kotlin/UInt
     public final get
 
-  // requires language version 1.3.0 (level=ERROR)
   // requires compiler version 1.4.30 (level=ERROR)
   // requires language version 1.4.0 (level=ERROR)
   // getter: ui_max()I
   public final val ui_max: kotlin/UInt
     public final get
 
-  // requires language version 1.3.0 (level=ERROR)
   // requires compiler version 1.4.30 (level=ERROR)
   // requires language version 1.4.0 (level=ERROR)
   // getter: ul()J
   public final val ul: kotlin/ULong
     public final get
 
-  // requires language version 1.3.0 (level=ERROR)
   // requires compiler version 1.4.30 (level=ERROR)
   // requires language version 1.4.0 (level=ERROR)
   // getter: ul_max()J
   public final val ul_max: kotlin/ULong
     public final get
 
-  // requires language version 1.3.0 (level=ERROR)
   // requires compiler version 1.4.30 (level=ERROR)
   // requires language version 1.4.0 (level=ERROR)
   // getter: us()S
   public final val us: kotlin/UShort
     public final get
 
-  // requires language version 1.3.0 (level=ERROR)
   // requires compiler version 1.4.30 (level=ERROR)
   // requires language version 1.4.0 (level=ERROR)
   // getter: us_max()S

libraries/tools/kotlinp/testData/ValueClass.txt

@@ -1,9 +1,7 @@
 // A.class
 // ------------------------------------------
-// requires language version 1.3.0 (level=ERROR)
 public final value class A : kotlin/Any {
 
-  // requires language version 1.3.0 (level=ERROR)
   // signature: constructor-impl(Ljava/lang/Integer;)Ljava/lang/Integer;
   public constructor(i: kotlin/Int?)
 
@@ -28,10 +26,8 @@ public final value class A : kotlin/Any {
 }
 // B.class
 // ------------------------------------------
-// requires language version 1.3.0 (level=ERROR)
 public final value class B : kotlin/Any {
 
-  // requires language version 1.3.0 (level=ERROR)
   // requires language version 1.3.0 (level=ERROR)
   // signature: constructor-impl(Lkotlin/jvm/functions/Function1;)Lkotlin/jvm/functions/Function1;
   public constructor(f: suspend kotlin/Function1<kotlin/coroutines/Continuation<kotlin/Unit>, kotlin/Any?>)
@@ -58,10 +54,8 @@ public final value class B : kotlin/Any {
 }
 // Z.class
 // ------------------------------------------
-// requires language version 1.3.0 (level=ERROR)
 public final value class Z : kotlin/Any {
 
-  // requires language version 1.3.0 (level=ERROR)
   // signature: constructor-impl(Ljava/lang/String;)Ljava/lang/String;
   public constructor(s: kotlin/String)