diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java b/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java
index 9f4ad62fbbf..f964f1ccce8 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/AsmUtil.java
@@ -491,7 +491,7 @@ public class AsmUtil {
             if (type == null || isNullableType(type)) continue;
 
             int index = frameMap.getIndex(parameter);
-            Type asmType = state.getTypeMapper().mapReturnType(type);
+            Type asmType = state.getTypeMapper().mapType(type);
             if (asmType.getSort() == Type.OBJECT || asmType.getSort() == Type.ARRAY) {
                 v.load(index, asmType);
                 v.visitLdcInsn(parameter.getName().asString());
diff --git a/compiler/testData/codegen/notNullAssertions/doGenerateParamAssertions.java b/compiler/testData/codegen/notNullAssertions/doGenerateParamAssertions.java
index deda44cb68f..147b5f5f921 100644
--- a/compiler/testData/codegen/notNullAssertions/doGenerateParamAssertions.java
+++ b/compiler/testData/codegen/notNullAssertions/doGenerateParamAssertions.java
@@ -2,13 +2,13 @@ package test;
 
 import org.jetbrains.annotations.NotNull;
 
-public abstract class doGenerateParamAssertions {
+public abstract class doGenerateParamAssertions<Type> {
 
-    public abstract void bar(@NotNull String s);
+    public abstract void doTest(@NotNull Type s);
     
-    public static void foo(doGenerateParamAssertions a) {
+    public static void runTest(doGenerateParamAssertions a) {
         try {
-            a.bar(null);
+            a.doTest(null);
         } catch (IllegalArgumentException e) {
             return;
         }
diff --git a/compiler/testData/codegen/notNullAssertions/doGenerateParamAssertions.kt b/compiler/testData/codegen/notNullAssertions/doGenerateParamAssertions.kt
index f887a801ddb..48ec8525c4b 100644
--- a/compiler/testData/codegen/notNullAssertions/doGenerateParamAssertions.kt
+++ b/compiler/testData/codegen/notNullAssertions/doGenerateParamAssertions.kt
@@ -1,8 +1,14 @@
 import test.doGenerateParamAssertions as C
 
-class A : C() {
-    override fun bar(s: String) {
-    }
+class TestString : C<String>() {
+    override fun doTest(s: String) { }
 }
 
-fun doTest() = C.foo(A())
+class TestUnit : C<Unit>() {
+    override fun doTest(s: Unit) { }
+}
+
+fun doTest() {
+    C.runTest(TestString())
+    C.runTest(TestUnit())
+}