diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/fixStack/FixStackAnalyzer.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/fixStack/FixStackAnalyzer.kt
index 6cd24cbb5d0..5041a6a5adf 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/fixStack/FixStackAnalyzer.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/fixStack/FixStackAnalyzer.kt
@@ -26,7 +26,6 @@ import org.jetbrains.org.objectweb.asm.tree.AbstractInsnNode
 import org.jetbrains.org.objectweb.asm.tree.JumpInsnNode
 import org.jetbrains.org.objectweb.asm.tree.LabelNode
 import org.jetbrains.org.objectweb.asm.tree.MethodNode
-import org.jetbrains.org.objectweb.asm.tree.analysis.AnalyzerException
 import org.jetbrains.org.objectweb.asm.tree.analysis.Frame
 import org.jetbrains.org.objectweb.asm.tree.analysis.Interpreter
 import kotlin.math.max
@@ -142,15 +141,14 @@ internal class FixStackAnalyzer(
 
             fun getStackContent(): List<FixStackValue> {
                 val savedStack = ArrayList<FixStackValue>()
-                IntRange(0, super.getStackSize() - 1).mapTo(savedStack) { super.getStack(it) }
+                for (i in 0 until super.getStackSize()) {
+                    savedStack.add(super.getStack(i))
+                }
                 savedStack.addAll(extraStack)
                 return savedStack
             }
 
             override fun push(value: FixStackValue) {
-                if (value == FixStackValue.UNINITIALIZED) {
-                    throw AnalyzerException(null, "Uninitialized value on stack")
-                }
                 if (super.getStackSize() < maxStackSize) {
                     super.push(value)
                 } else {
diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/fixStack/LocalVariablesManager.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/fixStack/LocalVariablesManager.kt
index 5501ed46220..9e48ab473e2 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/fixStack/LocalVariablesManager.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/optimization/fixStack/LocalVariablesManager.kt
@@ -51,6 +51,10 @@ internal class LocalVariablesManager(val context: FixStackContext, val methodNod
         saveStackMarker: AbstractInsnNode,
         savedStackValues: List<FixStackValue>
     ): SavedStackDescriptor {
+        if (savedStackValues.any { it == FixStackValue.UNINITIALIZED }) {
+            throw AssertionError("Uninitialized value on stack at ${methodNode.instructions.indexOf(saveStackMarker)}: $savedStackValues")
+        }
+
         val firstUnusedLocalVarIndex = getFirstUnusedLocalVariableIndex()
         val savedStackDescriptor = SavedStackDescriptor(savedStackValues, firstUnusedLocalVarIndex)
         updateMaxLocals(savedStackDescriptor.firstUnusedLocalVarIndex)