diff --git a/compiler/frontend.java/src/org/jetbrains/kotlin/fileClasses/JvmFileClassUtil.kt b/compiler/frontend.java/src/org/jetbrains/kotlin/fileClasses/JvmFileClassUtil.kt
index 4bb43d7368b..d3e3259bb95 100644
--- a/compiler/frontend.java/src/org/jetbrains/kotlin/fileClasses/JvmFileClassUtil.kt
+++ b/compiler/frontend.java/src/org/jetbrains/kotlin/fileClasses/JvmFileClassUtil.kt
@@ -33,13 +33,13 @@ object JvmFileClassUtil {
     val JVM_MULTIFILE_CLASS: FqName = FqName("kotlin.jvm.JvmMultifileClass")
     val JVM_MULTIFILE_CLASS_SHORT = JVM_MULTIFILE_CLASS.shortName().asString()
 
-    @JvmStatic fun getFileClassInfo(file: KtFile, jvmFileClassAnnotations: ParsedJvmFileClassAnnotations?): JvmFileClassInfo =
+    internal fun getFileClassInfo(file: KtFile, jvmFileClassAnnotations: ParsedJvmFileClassAnnotations?): JvmFileClassInfo =
             if (jvmFileClassAnnotations != null)
                 getFileClassInfoForAnnotation(file, jvmFileClassAnnotations)
             else
                 getDefaultFileClassInfo(file)
 
-    @JvmStatic fun getFileClassInfoForAnnotation(file: KtFile, jvmFileClassAnnotations: ParsedJvmFileClassAnnotations): JvmFileClassInfo =
+    private fun getFileClassInfoForAnnotation(file: KtFile, jvmFileClassAnnotations: ParsedJvmFileClassAnnotations): JvmFileClassInfo =
             if (jvmFileClassAnnotations.multipleFiles)
                 JvmMultifileClassPartInfo(getHiddenPartFqName(file, jvmFileClassAnnotations),
                                           getFacadeFqName(file, jvmFileClassAnnotations))
@@ -49,7 +49,7 @@ object JvmFileClassUtil {
     @JvmStatic fun getDefaultFileClassInfo(file: KtFile): JvmFileClassInfo =
             JvmSimpleFileClassInfo(PackagePartClassUtils.getPackagePartFqName(file.packageFqName, file.name), false)
 
-    @JvmStatic fun getFacadeFqName(file: KtFile, jvmFileClassAnnotations: ParsedJvmFileClassAnnotations): FqName =
+    private fun getFacadeFqName(file: KtFile, jvmFileClassAnnotations: ParsedJvmFileClassAnnotations): FqName =
             file.packageFqName.child(Name.identifier(jvmFileClassAnnotations.name))
 
     @JvmStatic fun getPartFqNameForDeserializedCallable(callable: DeserializedCallableMemberDescriptor): FqName {
@@ -61,7 +61,7 @@ object JvmFileClassUtil {
     @JvmStatic fun getImplClassName(callable: DeserializedCallableMemberDescriptor): Name? =
             callable.getImplClassNameForDeserialized()
 
-    @JvmStatic fun getHiddenPartFqName(file: KtFile, jvmFileClassAnnotations: ParsedJvmFileClassAnnotations): FqName =
+    private fun getHiddenPartFqName(file: KtFile, jvmFileClassAnnotations: ParsedJvmFileClassAnnotations): FqName =
             file.packageFqName.child(Name.identifier(manglePartName(jvmFileClassAnnotations.name, file.name)))
 
     @JvmStatic fun manglePartName(facadeName: String, fileName: String): String =
@@ -70,7 +70,7 @@ object JvmFileClassUtil {
     @JvmStatic fun getFileClassInfoNoResolve(file: KtFile): JvmFileClassInfo =
             getFileClassInfo(file, parseJvmNameOnFileNoResolve(file))
 
-    @JvmStatic fun parseJvmNameOnFileNoResolve(file: KtFile): ParsedJvmFileClassAnnotations? {
+    internal fun parseJvmNameOnFileNoResolve(file: KtFile): ParsedJvmFileClassAnnotations? {
         val jvmName = findAnnotationEntryOnFileNoResolve(file, JVM_NAME_SHORT) ?: return null
         val nameExpr = jvmName.valueArguments.firstOrNull()?.getArgumentExpression() ?: return null
         val name = getLiteralStringFromRestrictedConstExpression(nameExpr) ?: return null
@@ -94,7 +94,7 @@ object JvmFileClassUtil {
     }
 }
 
-private class ParsedJvmFileClassAnnotations(val name: String, val multipleFiles: Boolean)
+internal class ParsedJvmFileClassAnnotations(val name: String, val multipleFiles: Boolean)
 
 val KtFile.javaFileFacadeFqName: FqName
     get() {
diff --git a/core/descriptors.runtime/src/org/jetbrains/kotlin/load/java/components/RuntimeSourceElementFactory.kt b/core/descriptors.runtime/src/org/jetbrains/kotlin/load/java/components/RuntimeSourceElementFactory.kt
index 75c60758783..4cd53b907db 100644
--- a/core/descriptors.runtime/src/org/jetbrains/kotlin/load/java/components/RuntimeSourceElementFactory.kt
+++ b/core/descriptors.runtime/src/org/jetbrains/kotlin/load/java/components/RuntimeSourceElementFactory.kt
@@ -28,5 +28,5 @@ object RuntimeSourceElementFactory : JavaSourceElementFactory {
         override fun getContainingFile(): SourceFile = SourceFile.NO_SOURCE_FILE
     }
 
-    override fun source(javaElement: JavaElement) = RuntimeSourceElement(javaElement as ReflectJavaElement)
+    override fun source(javaElement: JavaElement): JavaSourceElement = RuntimeSourceElement(javaElement as ReflectJavaElement)
 }
diff --git a/core/descriptors/src/org/jetbrains/kotlin/builtins/KotlinBuiltIns.java b/core/descriptors/src/org/jetbrains/kotlin/builtins/KotlinBuiltIns.java
index 6416a374dc9..1b701cfc6eb 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/builtins/KotlinBuiltIns.java
+++ b/core/descriptors/src/org/jetbrains/kotlin/builtins/KotlinBuiltIns.java
@@ -937,7 +937,7 @@ public abstract class KotlinBuiltIns {
         if (!BUILT_INS_PACKAGE_NAME.equals(first(segments))) return false;
 
         String shortName = last(segments).asString();
-        return BuiltInFictitiousFunctionClassFactory.parseClassName(shortName, BUILT_INS_PACKAGE_FQ_NAME) != null;
+        return BuiltInFictitiousFunctionClassFactory.isFunctionClassName(shortName, BUILT_INS_PACKAGE_FQ_NAME);
     }
 
     @Nullable
diff --git a/core/descriptors/src/org/jetbrains/kotlin/builtins/functions/BuiltInFictitiousFunctionClassFactory.kt b/core/descriptors/src/org/jetbrains/kotlin/builtins/functions/BuiltInFictitiousFunctionClassFactory.kt
index abc1952f645..5736598864e 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/builtins/functions/BuiltInFictitiousFunctionClassFactory.kt
+++ b/core/descriptors/src/org/jetbrains/kotlin/builtins/functions/BuiltInFictitiousFunctionClassFactory.kt
@@ -35,7 +35,7 @@ class BuiltInFictitiousFunctionClassFactory(
     private data class KindWithArity(val kind: Kind, val arity: Int)
 
     companion object {
-        @JvmStatic fun parseClassName(className: String, packageFqName: FqName): KindWithArity? {
+        private fun parseClassName(className: String, packageFqName: FqName): KindWithArity? {
             val kind = FunctionClassDescriptor.Kind.byPackage(packageFqName) ?: return null
 
             val prefix = kind.classNamePrefix
@@ -47,6 +47,9 @@ class BuiltInFictitiousFunctionClassFactory(
             return KindWithArity(kind, arity)
         }
 
+        @JvmStatic fun isFunctionClassName(className: String, packageFqName: FqName) =
+                parseClassName(className, packageFqName) != null
+
         private fun toInt(s: String): Int? {
             if (s.isEmpty()) return null
 
diff --git a/idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/Weighers.kt b/idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/Weighers.kt
index 657fe5ac05c..70a44527252 100644
--- a/idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/Weighers.kt
+++ b/idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/Weighers.kt
@@ -112,7 +112,7 @@ object KindWeigher : LookupElementWeigher("kotlin.kind") {
         packages
     }
 
-    override fun weigh(element: LookupElement): Weight {
+    override fun weigh(element: LookupElement): Comparable<*> {
         val o = element.`object`
 
         return when (o) {
@@ -144,7 +144,7 @@ object VariableOrFunctionWeigher : LookupElementWeigher("kotlin.variableOrFuncti
         function
     }
 
-    override fun weigh(element: LookupElement): Weight? {
+    override fun weigh(element: LookupElement): Comparable<*>? {
         val descriptor = (element.`object` as? DeclarationLookupObject)?.descriptor ?: return null
         return when (descriptor) {
             is VariableDescriptor -> Weight.variable
@@ -169,7 +169,7 @@ object PreferMatchingItemWeigher : LookupElementWeigher("kotlin.preferMatching",
         notExactMatch
     }
 
-    override fun weigh(element: LookupElement, context: WeighingContext): Weight {
+    override fun weigh(element: LookupElement, context: WeighingContext): Comparable<*> {
         val prefix = context.itemPattern(element)
         if (element.lookupString != prefix) {
             return Weight.notExactMatch