diff --git a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/ir/IrUtils.kt b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/ir/IrUtils.kt
index 03cae8ab5a4..c3348ff020a 100644
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/ir/IrUtils.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/ir/IrUtils.kt
@@ -664,7 +664,7 @@ fun IrExpression?.isPure(
             }
             is IrCall -> context?.isSideEffectFree(this) ?: false
             is IrGetObjectValue -> type.isUnit()
-            is IrVararg -> elements.all { (it as? IrExpression).isPure(anyVariable, checkFields, context) }
+            is IrVararg -> elements.all { (it as? IrExpression)?.isPure(anyVariable, checkFields, context) == true }
             else -> false
         }
     }