IR: handle IrVararg.varargElementType in RemapTypes

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

@@ -148,6 +148,11 @@ class ScopeValidator(
         super.visitClassReference(expression)
     }
 
+    override fun visitVararg(expression: IrVararg) {
+        visitTypeAccess(expression, expression.varargElementType)
+        super.visitVararg(expression)
+    }
+
     override fun visitExpression(expression: IrExpression) {
         visitTypeAccess(expression, expression.type)
         super.visitExpression(expression)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/IrVararg.kt

@@ -24,7 +24,7 @@ import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 interface IrVarargElement : IrElement
 
 abstract class IrVararg : IrExpression() {
-    abstract val varargElementType: IrType
+    abstract var varargElementType: IrType
 
     abstract val elements: List<IrVarargElement>
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/impl/IrVarargImpl.kt

@@ -27,7 +27,7 @@ class IrVarargImpl(
     override val startOffset: Int,
     override val endOffset: Int,
     override var type: IrType,
-    override val varargElementType: IrType
+    override var varargElementType: IrType
 ) : IrVararg() {
     constructor(
         startOffset: Int,

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

@@ -10,6 +10,7 @@ import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrMemberAccessExpression
 import org.jetbrains.kotlin.ir.expressions.IrTypeOperatorCall
+import org.jetbrains.kotlin.ir.expressions.IrVararg
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
 import org.jetbrains.kotlin.ir.visitors.acceptVoid
@@ -83,4 +84,8 @@ private class RemapTypesHelper(private val typeRemapper: TypeRemapper) : IrEleme
         super.visitTypeOperator(expression)
     }
 
+    override fun visitVararg(expression: IrVararg) {
+        expression.varargElementType = typeRemapper.remapType(expression.varargElementType)
+        super.visitVararg(expression)
+    }
 }