diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java b/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java
index 8e2418b9070..e9ed5da8688 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java
@@ -71,7 +71,6 @@ public class AsmUtil {
 
     private static final Set<Type> STRING_BUILDER_OBJECT_APPEND_ARG_TYPES = Sets.newHashSet(
             getType(String.class),
-            getType(StringBuilder.class),
             getType(StringBuffer.class),
             getType(CharSequence.class)
     );