diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/state/JetTypeMapper.java b/compiler/backend/src/org/jetbrains/jet/codegen/state/JetTypeMapper.java
index df8808acb96..a826e437f40 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/state/JetTypeMapper.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/state/JetTypeMapper.java
@@ -446,7 +446,7 @@ public class JetTypeMapper extends BindingTraceAware {
     ) {
         DeclarationDescriptor functionParent = functionDescriptor.getOriginal().getContainingDeclaration();
 
-        functionDescriptor = unwrapFakeOverride(functionDescriptor);
+        functionDescriptor = unwrapFakeOverride(functionDescriptor.getOriginal());
 
         JvmMethodSignature descriptor = mapSignature(functionDescriptor.getOriginal(), true, kind);
         Type owner;
diff --git a/compiler/testData/codegen/box/fakeOverride/diamondFunction.kt b/compiler/testData/codegen/box/fakeOverride/diamondFunction.kt
new file mode 100644
index 00000000000..7c150aaaa7b
--- /dev/null
+++ b/compiler/testData/codegen/box/fakeOverride/diamondFunction.kt
@@ -0,0 +1,31 @@
+trait T {
+    fun foo(): Unit
+}
+
+open class A : T {
+    override fun foo() {}
+}
+
+trait B : T
+
+class C : A(), B
+class D : B, A()
+class E : A(), B, T
+class F : B, A(), T
+class G : A(), T, B
+class H : B, T, A()
+class I : T, A(), B
+class J : T, B, A()
+
+fun box(): String {
+    C().foo()
+    D().foo()
+    E().foo()
+    F().foo()
+    G().foo()
+    H().foo()
+    I().foo()
+    J().foo()
+
+    return "OK"
+}
diff --git a/compiler/testData/codegen/box/fakeOverride/function.kt b/compiler/testData/codegen/box/fakeOverride/function.kt
new file mode 100644
index 00000000000..1158cddb0c9
--- /dev/null
+++ b/compiler/testData/codegen/box/fakeOverride/function.kt
@@ -0,0 +1,35 @@
+trait T {
+    fun foo(): Unit
+}
+
+open class A : T {
+    override fun foo(): Unit {}
+}
+
+class B : A(), T
+class C : T, A()
+
+trait U : T
+class D : U, A()
+class E : A(), U
+class F : U, T, A()
+class G : T, U, A()
+class H : U, A(), T
+class I : T, A(), U
+class J : A(), U, T
+class K : A(), T, U
+
+fun box(): String {
+    B().foo()
+    C().foo()
+    D().foo()
+    E().foo()
+    F().foo()
+    G().foo()
+    H().foo()
+    I().foo()
+    J().foo()
+    K().foo()
+
+    return "OK"
+}
diff --git a/compiler/testData/codegen/box/fakeOverride/propertyGetter.kt b/compiler/testData/codegen/box/fakeOverride/propertyGetter.kt
new file mode 100644
index 00000000000..0c86e6eacab
--- /dev/null
+++ b/compiler/testData/codegen/box/fakeOverride/propertyGetter.kt
@@ -0,0 +1,37 @@
+trait T {
+    val foo: String
+}
+
+open class A : T {
+    override val foo: String = ""
+}
+
+class B : A(), T
+class C : T, A()
+
+trait U : T
+
+class D : U, A()
+class E : A(), U
+class F : U, T, A()
+class G : T, U, A()
+class H : U, A(), T
+class I : T, A(), U
+class J : A(), U, T
+class K : A(), T, U
+
+fun box(): String {
+    B().foo
+    C().foo
+
+    D().foo
+    E().foo
+    F().foo
+    G().foo
+    H().foo
+    I().foo
+    J().foo
+    K().foo
+
+    return "OK"
+}
diff --git a/compiler/testData/codegen/box/fakeOverride/propertySetter.kt b/compiler/testData/codegen/box/fakeOverride/propertySetter.kt
new file mode 100644
index 00000000000..2103491b1ad
--- /dev/null
+++ b/compiler/testData/codegen/box/fakeOverride/propertySetter.kt
@@ -0,0 +1,18 @@
+trait T {
+    var result: String
+}
+
+open class A : T {
+    override var result: String
+        get() = ""
+        set(value) {}
+}
+
+class B : A(), T
+class C : T, A()
+
+fun box(): String {
+    B().result = ""
+    C().result = ""
+    return "OK"
+}
diff --git a/compiler/tests/org/jetbrains/jet/codegen/generated/BlackBoxCodegenTestGenerated.java b/compiler/tests/org/jetbrains/jet/codegen/generated/BlackBoxCodegenTestGenerated.java
index 44bfd68e6a7..6dec0ea06a6 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/generated/BlackBoxCodegenTestGenerated.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/generated/BlackBoxCodegenTestGenerated.java
@@ -31,7 +31,7 @@ import org.jetbrains.jet.codegen.generated.AbstractBlackBoxCodegenTest;
 /** This class is generated by {@link org.jetbrains.jet.generators.tests.GenerateTests}. DO NOT MODIFY MANUALLY */
 @SuppressWarnings("all")
 @TestMetadata("compiler/testData/codegen/box")
-@InnerTestClasses({BlackBoxCodegenTestGenerated.Arrays.class, BlackBoxCodegenTestGenerated.Bridges.class, BlackBoxCodegenTestGenerated.BuiltinStubMethods.class, BlackBoxCodegenTestGenerated.CallableReference.class, BlackBoxCodegenTestGenerated.Casts.class, BlackBoxCodegenTestGenerated.Classes.class, BlackBoxCodegenTestGenerated.Closures.class, BlackBoxCodegenTestGenerated.Constants.class, BlackBoxCodegenTestGenerated.ControlStructures.class, BlackBoxCodegenTestGenerated.DefaultArguments.class, BlackBoxCodegenTestGenerated.DelegatedProperty.class, BlackBoxCodegenTestGenerated.Elvis.class, BlackBoxCodegenTestGenerated.Enum.class, BlackBoxCodegenTestGenerated.ExclExcl.class, BlackBoxCodegenTestGenerated.ExtensionFunctions.class, BlackBoxCodegenTestGenerated.ExtensionProperties.class, BlackBoxCodegenTestGenerated.FieldRename.class, BlackBoxCodegenTestGenerated.Finally.class, BlackBoxCodegenTestGenerated.Functions.class, BlackBoxCodegenTestGenerated.InnerNested.class, BlackBoxCodegenTestGenerated.Instructions.class, BlackBoxCodegenTestGenerated.Intrinsics.class, BlackBoxCodegenTestGenerated.Labels.class, BlackBoxCodegenTestGenerated.LocalClasses.class, BlackBoxCodegenTestGenerated.MultiDecl.class, BlackBoxCodegenTestGenerated.Namespace.class, BlackBoxCodegenTestGenerated.Objects.class, BlackBoxCodegenTestGenerated.OperatorConventions.class, BlackBoxCodegenTestGenerated.PrimitiveTypes.class, BlackBoxCodegenTestGenerated.Properties.class, BlackBoxCodegenTestGenerated.Reflection.class, BlackBoxCodegenTestGenerated.SafeCall.class, BlackBoxCodegenTestGenerated.SamConstructors.class, BlackBoxCodegenTestGenerated.Strings.class, BlackBoxCodegenTestGenerated.Super.class, BlackBoxCodegenTestGenerated.ToArray.class, BlackBoxCodegenTestGenerated.Traits.class, BlackBoxCodegenTestGenerated.TypeInfo.class, BlackBoxCodegenTestGenerated.TypeMapping.class, BlackBoxCodegenTestGenerated.Unit.class, BlackBoxCodegenTestGenerated.Vararg.class, BlackBoxCodegenTestGenerated.When.class})
+@InnerTestClasses({BlackBoxCodegenTestGenerated.Arrays.class, BlackBoxCodegenTestGenerated.Bridges.class, BlackBoxCodegenTestGenerated.BuiltinStubMethods.class, BlackBoxCodegenTestGenerated.CallableReference.class, BlackBoxCodegenTestGenerated.Casts.class, BlackBoxCodegenTestGenerated.Classes.class, BlackBoxCodegenTestGenerated.Closures.class, BlackBoxCodegenTestGenerated.Constants.class, BlackBoxCodegenTestGenerated.ControlStructures.class, BlackBoxCodegenTestGenerated.DefaultArguments.class, BlackBoxCodegenTestGenerated.DelegatedProperty.class, BlackBoxCodegenTestGenerated.Elvis.class, BlackBoxCodegenTestGenerated.Enum.class, BlackBoxCodegenTestGenerated.ExclExcl.class, BlackBoxCodegenTestGenerated.ExtensionFunctions.class, BlackBoxCodegenTestGenerated.ExtensionProperties.class, BlackBoxCodegenTestGenerated.FakeOverride.class, BlackBoxCodegenTestGenerated.FieldRename.class, BlackBoxCodegenTestGenerated.Finally.class, BlackBoxCodegenTestGenerated.Functions.class, BlackBoxCodegenTestGenerated.InnerNested.class, BlackBoxCodegenTestGenerated.Instructions.class, BlackBoxCodegenTestGenerated.Intrinsics.class, BlackBoxCodegenTestGenerated.Labels.class, BlackBoxCodegenTestGenerated.LocalClasses.class, BlackBoxCodegenTestGenerated.MultiDecl.class, BlackBoxCodegenTestGenerated.Namespace.class, BlackBoxCodegenTestGenerated.Objects.class, BlackBoxCodegenTestGenerated.OperatorConventions.class, BlackBoxCodegenTestGenerated.PrimitiveTypes.class, BlackBoxCodegenTestGenerated.Properties.class, BlackBoxCodegenTestGenerated.Reflection.class, BlackBoxCodegenTestGenerated.SafeCall.class, BlackBoxCodegenTestGenerated.SamConstructors.class, BlackBoxCodegenTestGenerated.Strings.class, BlackBoxCodegenTestGenerated.Super.class, BlackBoxCodegenTestGenerated.ToArray.class, BlackBoxCodegenTestGenerated.Traits.class, BlackBoxCodegenTestGenerated.TypeInfo.class, BlackBoxCodegenTestGenerated.TypeMapping.class, BlackBoxCodegenTestGenerated.Unit.class, BlackBoxCodegenTestGenerated.Vararg.class, BlackBoxCodegenTestGenerated.When.class})
 public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
     public void testAllFilesPresentInBox() throws Exception {
         JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), "org.jetbrains.jet.generators.tests.GenerateTests", new File("compiler/testData/codegen/box"), Pattern.compile("^(.+)\\.kt$"), true);
@@ -2274,6 +2274,34 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
         
     }
     
+    @TestMetadata("compiler/testData/codegen/box/fakeOverride")
+    public static class FakeOverride extends AbstractBlackBoxCodegenTest {
+        public void testAllFilesPresentInFakeOverride() throws Exception {
+            JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), "org.jetbrains.jet.generators.tests.GenerateTests", new File("compiler/testData/codegen/box/fakeOverride"), Pattern.compile("^(.+)\\.kt$"), true);
+        }
+        
+        @TestMetadata("diamondFunction.kt")
+        public void testDiamondFunction() throws Exception {
+            doTest("compiler/testData/codegen/box/fakeOverride/diamondFunction.kt");
+        }
+        
+        @TestMetadata("function.kt")
+        public void testFunction() throws Exception {
+            doTest("compiler/testData/codegen/box/fakeOverride/function.kt");
+        }
+        
+        @TestMetadata("propertyGetter.kt")
+        public void testPropertyGetter() throws Exception {
+            doTest("compiler/testData/codegen/box/fakeOverride/propertyGetter.kt");
+        }
+        
+        @TestMetadata("propertySetter.kt")
+        public void testPropertySetter() throws Exception {
+            doTest("compiler/testData/codegen/box/fakeOverride/propertySetter.kt");
+        }
+        
+    }
+    
     @TestMetadata("compiler/testData/codegen/box/fieldRename")
     public static class FieldRename extends AbstractBlackBoxCodegenTest {
         public void testAllFilesPresentInFieldRename() throws Exception {
@@ -4936,6 +4964,7 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
         suite.addTestSuite(ExclExcl.class);
         suite.addTestSuite(ExtensionFunctions.class);
         suite.addTestSuite(ExtensionProperties.class);
+        suite.addTestSuite(FakeOverride.class);
         suite.addTestSuite(FieldRename.class);
         suite.addTestSuite(Finally.class);
         suite.addTest(Functions.innerSuite());