diff --git a/jps/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/IncrementalCacheImpl.kt b/jps/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/IncrementalCacheImpl.kt
index 21537fd9d34..afb9f5032c7 100644
--- a/jps/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/IncrementalCacheImpl.kt
+++ b/jps/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/IncrementalCacheImpl.kt
@@ -30,10 +30,7 @@ import org.jetbrains.kotlin.jps.build.GeneratedJvmClass
 import org.jetbrains.kotlin.jps.build.KotlinBuilder
 import org.jetbrains.kotlin.jps.incremental.storage.*
 import org.jetbrains.kotlin.load.kotlin.ModuleMapping
-import org.jetbrains.kotlin.load.kotlin.header.isCompatibleClassKind
-import org.jetbrains.kotlin.load.kotlin.header.isCompatibleFileFacadeKind
-import org.jetbrains.kotlin.load.kotlin.header.isCompatibleMultifileClassKind
-import org.jetbrains.kotlin.load.kotlin.header.isCompatibleMultifileClassPartKind
+import org.jetbrains.kotlin.load.kotlin.header.KotlinClassHeader
 import org.jetbrains.kotlin.load.kotlin.incremental.components.IncrementalCache
 import org.jetbrains.kotlin.load.kotlin.incremental.components.JvmPackagePartProto
 import org.jetbrains.kotlin.name.FqName
@@ -147,8 +144,12 @@ open class IncrementalCacheImpl(
         }
 
         val header = kotlinClass.classHeader
-        val changesInfo = when {
-            header.isCompatibleFileFacadeKind() -> {
+        if (header.isLocalClass) {
+            return CompilationResult.NO_CHANGES
+        }
+
+        val changesInfo = when (header.kind) {
+            KotlinClassHeader.Kind.FILE_FACADE -> {
                 assert(sourceFiles.size == 1) { "Package part from several source files: $sourceFiles" }
                 packagePartMap.addPackagePart(className)
 
@@ -156,7 +157,7 @@ open class IncrementalCacheImpl(
                 constantsMap.process(kotlinClass) +
                 additionalProcessChangedClass(kotlinClass, isPackage = true)
             }
-            header.isCompatibleMultifileClassKind() -> {
+            KotlinClassHeader.Kind.MULTIFILE_CLASS -> {
                 val partNames = kotlinClass.classHeader.filePartClassNames?.toList()
                                 ?: throw AssertionError("Multifile class has no parts: ${kotlinClass.className}")
                 multifileClassFacadeMap.add(className, partNames)
@@ -165,7 +166,7 @@ open class IncrementalCacheImpl(
                 constantsMap.process(kotlinClass) +
                 additionalProcessChangedClass(kotlinClass, isPackage = true)
             }
-            header.isCompatibleMultifileClassPartKind() -> {
+            KotlinClassHeader.Kind.MULTIFILE_CLASS_PART -> {
                 assert(sourceFiles.size == 1) { "Multifile class part from several source files: $sourceFiles" }
                 packagePartMap.addPackagePart(className)
                 multifileClassPartMap.add(className.internalName, header.multifileClassName!!)
@@ -174,7 +175,7 @@ open class IncrementalCacheImpl(
                 constantsMap.process(kotlinClass) +
                 additionalProcessChangedClass(kotlinClass, isPackage = true)
             }
-            header.isCompatibleClassKind() && !header.isLocalClass -> {
+            KotlinClassHeader.Kind.CLASS -> {
                 addToClassStorage(kotlinClass)
 
                 protoMap.process(kotlinClass, isPackage = false) +
diff --git a/jps/jps-plugin/test/org/jetbrains/kotlin/jps/build/classFilesComparison/classFilesComparison.kt b/jps/jps-plugin/test/org/jetbrains/kotlin/jps/build/classFilesComparison/classFilesComparison.kt
index 4fa17591046..a9e51f5b98d 100644
--- a/jps/jps-plugin/test/org/jetbrains/kotlin/jps/build/classFilesComparison/classFilesComparison.kt
+++ b/jps/jps-plugin/test/org/jetbrains/kotlin/jps/build/classFilesComparison/classFilesComparison.kt
@@ -22,9 +22,7 @@ import com.google.common.io.Files
 import com.google.protobuf.ExtensionRegistry
 import com.intellij.openapi.util.io.FileUtil
 import org.jetbrains.kotlin.jps.incremental.LocalFileKotlinClass
-import org.jetbrains.kotlin.load.kotlin.header.isCompatibleClassKind
-import org.jetbrains.kotlin.load.kotlin.header.isCompatibleFileFacadeKind
-import org.jetbrains.kotlin.load.kotlin.header.isCompatibleMultifileClassPartKind
+import org.jetbrains.kotlin.load.kotlin.header.KotlinClassHeader
 import org.jetbrains.kotlin.serialization.DebugProtoBuf
 import org.jetbrains.kotlin.serialization.jvm.BitEncoding
 import org.jetbrains.kotlin.serialization.jvm.DebugJvmProtoBuf
@@ -141,14 +139,17 @@ fun classFileToString(classFile: File): String {
 
             out.write("\n------ string table types proto -----\n${DebugJvmProtoBuf.StringTableTypes.parseDelimitedFrom(input)}")
 
-            when {
-                classHeader!!.isCompatibleFileFacadeKind() ->
-                    out.write("\n------ file facade proto -----\n${DebugProtoBuf.Package.parseFrom(input, getExtensionRegistry())}")
-                classHeader.isCompatibleClassKind() ->
-                    out.write("\n------ class proto -----\n${DebugProtoBuf.Class.parseFrom(input, getExtensionRegistry())}")
-                classHeader.isCompatibleMultifileClassPartKind() ->
-                    out.write("\n------ multi-file part proto -----\n${DebugProtoBuf.Package.parseFrom(input, getExtensionRegistry())}")
+            if (!classHeader!!.metadataVersion.isCompatible()) {
+                error("Incompatible class ($classHeader): $classFile")
+            }
 
+            when (classHeader.kind) {
+                KotlinClassHeader.Kind.FILE_FACADE ->
+                    out.write("\n------ file facade proto -----\n${DebugProtoBuf.Package.parseFrom(input, getExtensionRegistry())}")
+                KotlinClassHeader.Kind.CLASS ->
+                    out.write("\n------ class proto -----\n${DebugProtoBuf.Class.parseFrom(input, getExtensionRegistry())}")
+                KotlinClassHeader.Kind.MULTIFILE_CLASS_PART ->
+                    out.write("\n------ multi-file part proto -----\n${DebugProtoBuf.Package.parseFrom(input, getExtensionRegistry())}")
                 else -> throw IllegalStateException()
             }
         }
diff --git a/jps/jps-plugin/test/org/jetbrains/kotlin/jps/incremental/AbstractProtoComparisonTest.kt b/jps/jps-plugin/test/org/jetbrains/kotlin/jps/incremental/AbstractProtoComparisonTest.kt
index f9ae0e18edc..77fdb5fc752 100644
--- a/jps/jps-plugin/test/org/jetbrains/kotlin/jps/incremental/AbstractProtoComparisonTest.kt
+++ b/jps/jps-plugin/test/org/jetbrains/kotlin/jps/incremental/AbstractProtoComparisonTest.kt
@@ -20,9 +20,7 @@ import com.intellij.openapi.util.io.FileUtil
 import com.intellij.testFramework.UsefulTestCase
 import com.intellij.util.SmartList
 import org.jetbrains.kotlin.jps.incremental.storage.ProtoMapValue
-import org.jetbrains.kotlin.load.kotlin.header.isCompatibleClassKind
-import org.jetbrains.kotlin.load.kotlin.header.isCompatibleFileFacadeKind
-import org.jetbrains.kotlin.load.kotlin.header.isCompatibleMultifileClassPartKind
+import org.jetbrains.kotlin.load.kotlin.header.KotlinClassHeader
 import org.jetbrains.kotlin.serialization.jvm.BitEncoding
 import org.jetbrains.kotlin.test.KotlinTestUtils
 import org.jetbrains.kotlin.test.MockLibraryUtil
@@ -93,19 +91,22 @@ abstract class AbstractProtoComparisonTest : UsefulTestCase() {
         val oldProtoBytes = BitEncoding.decodeBytes(oldClassHeader.annotationData!!)
         val newProtoBytes = BitEncoding.decodeBytes(newClassHeader.annotationData!!)
 
+        assert(oldClassHeader.metadataVersion.isCompatible()) { "Incompatible class ($oldClassHeader): $oldClassFile" }
+        assert(newClassHeader.metadataVersion.isCompatible()) { "Incompatible class ($newClassHeader): $newClassFile" }
+
         val oldProto = ProtoMapValue(
-                oldClassHeader.isCompatibleFileFacadeKind() || oldClassHeader.isCompatibleMultifileClassPartKind(),
+                oldClassHeader.kind == KotlinClassHeader.Kind.FILE_FACADE ||
+                oldClassHeader.kind == KotlinClassHeader.Kind.MULTIFILE_CLASS_PART,
                 oldProtoBytes, oldClassHeader.strings!!
         )
         val newProto = ProtoMapValue(
-                newClassHeader.isCompatibleFileFacadeKind() || newClassHeader.isCompatibleMultifileClassPartKind(),
+                newClassHeader.kind == KotlinClassHeader.Kind.FILE_FACADE ||
+                newClassHeader.kind == KotlinClassHeader.Kind.MULTIFILE_CLASS_PART,
                 newProtoBytes, newClassHeader.strings!!
         )
 
-        val diff = when {
-            newClassHeader.isCompatibleClassKind() ||
-            newClassHeader.isCompatibleFileFacadeKind() ||
-            newClassHeader.isCompatibleMultifileClassPartKind() ->
+        val diff = when (newClassHeader.kind) {
+            KotlinClassHeader.Kind.CLASS, KotlinClassHeader.Kind.FILE_FACADE, KotlinClassHeader.Kind.MULTIFILE_CLASS_PART ->
                 difference(oldProto, newProto)
             else ->  {
                 println("ignore ${oldLocalFileKotlinClass.classId}")