diff --git a/compiler/backend-common/src/org/jetbrains/kotlin/backend/common/CodegenUtil.kt b/compiler/backend-common/src/org/jetbrains/kotlin/backend/common/CodegenUtil.kt
index 40a25ecbc79..80d27fac127 100644
--- a/compiler/backend-common/src/org/jetbrains/kotlin/backend/common/CodegenUtil.kt
+++ b/compiler/backend-common/src/org/jetbrains/kotlin/backend/common/CodegenUtil.kt
@@ -71,8 +71,7 @@ object CodegenUtil {
     }
 
     private fun doesOverride(overrideCandidate: CallableMemberDescriptor, overriddenDescriptor: CallableMemberDescriptor) =
-        (listOf(overrideCandidate) + DescriptorUtils.getAllOverriddenDescriptors(overrideCandidate))
-                .map(CallableMemberDescriptor::getOriginal)
+        (listOf(overrideCandidate.original) + DescriptorUtils.getAllOverriddenDescriptors(overrideCandidate))
                 .contains(overriddenDescriptor.original)
 
     @JvmStatic
diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/state/KotlinTypeMapper.java b/compiler/backend/src/org/jetbrains/kotlin/codegen/state/KotlinTypeMapper.java
index 2b37ac8549c..97fad151398 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/state/KotlinTypeMapper.java
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/state/KotlinTypeMapper.java
@@ -1075,7 +1075,7 @@ public class KotlinTypeMapper {
 
         for (FunctionDescriptor overridden : getAllOverriddenDescriptors(descriptor)) {
             //noinspection ConstantConditions
-            if (!KotlinBuiltIns.isPrimitiveType(overridden.getOriginal().getReturnType())) return true;
+            if (!KotlinBuiltIns.isPrimitiveType(overridden.getReturnType())) return true;
         }
 
         return false;
diff --git a/compiler/testData/codegen/box/delegation/kt8154.kt b/compiler/testData/codegen/box/delegation/kt8154.kt
new file mode 100644
index 00000000000..86550e49f60
--- /dev/null
+++ b/compiler/testData/codegen/box/delegation/kt8154.kt
@@ -0,0 +1,19 @@
+interface A<T> {
+    fun foo(): T
+}
+
+interface B<T> : A<T>
+
+class BImpl<T>(a: A<T>) : B<T>, A<T> by a
+
+fun box(): String {
+    val b: B<String> = BImpl(object : A<String> {
+        override fun foo() = "OK"
+    })
+
+    if (b.foo() != "OK") return "fail 1"
+
+    val a: A<String> = b
+
+    return a.foo()
+}
diff --git a/compiler/testData/diagnostics/tests/delegation/kt8154.kt b/compiler/testData/diagnostics/tests/delegation/kt8154.kt
new file mode 100644
index 00000000000..066fef5fa23
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/delegation/kt8154.kt
@@ -0,0 +1,11 @@
+interface A<T> {
+    fun foo()
+}
+
+interface B<T> : A<T> {
+    fun bar()
+}
+
+class BImpl<T>(a: A<T>) : B<T>, A<T> by a {
+    override fun bar() { throw UnsupportedOperationException() }
+}
diff --git a/compiler/testData/diagnostics/tests/delegation/kt8154.txt b/compiler/testData/diagnostics/tests/delegation/kt8154.txt
new file mode 100644
index 00000000000..2d0a3a8e1c5
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/delegation/kt8154.txt
@@ -0,0 +1,25 @@
+package
+
+public interface A</*0*/ T> {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public abstract fun foo(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface B</*0*/ T> : A<T> {
+    public abstract fun bar(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public abstract override /*1*/ /*fake_override*/ fun foo(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class BImpl</*0*/ T> : B<T>, A<T> {
+    public constructor BImpl</*0*/ T>(/*0*/ a: A<T>)
+    public open override /*1*/ fun bar(): kotlin.Unit
+    public open override /*2*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*2*/ /*delegation*/ fun foo(): kotlin.Unit
+    public open override /*2*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*2*/ /*fake_override*/ fun toString(): kotlin.String
+}
diff --git a/compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java b/compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java
index eb75bfda199..85ca6ae751a 100644
--- a/compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java
+++ b/compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java
@@ -5748,6 +5748,12 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                 doTest(fileName);
             }
 
+            @TestMetadata("kt8154.kt")
+            public void testKt8154() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegation/kt8154.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("compiler/testData/diagnostics/tests/delegation/clashes")
             @TestDataPath("$PROJECT_ROOT")
             @RunWith(JUnit3RunnerWithInners.class)
diff --git a/compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java b/compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java
index da489e48b10..b974114a9c4 100644
--- a/compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java
+++ b/compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java
@@ -5655,6 +5655,12 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/box/delegation/delegationToVal.kt");
             doTest(fileName);
         }
+
+        @TestMetadata("kt8154.kt")
+        public void testKt8154() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/box/delegation/kt8154.kt");
+            doTest(fileName);
+        }
     }
 
     @TestMetadata("compiler/testData/codegen/box/destructuringDeclInLambdaParam")
diff --git a/core/descriptors/src/org/jetbrains/kotlin/resolve/DescriptorUtils.java b/core/descriptors/src/org/jetbrains/kotlin/resolve/DescriptorUtils.java
index 8d771b2e39f..6f05d33b5e5 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/resolve/DescriptorUtils.java
+++ b/core/descriptors/src/org/jetbrains/kotlin/resolve/DescriptorUtils.java
@@ -469,6 +469,9 @@ public class DescriptorUtils {
         return classDescriptor.getModality() != Modality.FINAL || classDescriptor.getKind() == ClassKind.ENUM_CLASS;
     }
 
+    /**
+     * @return original (not substituted) descriptors without any duplicates
+     */
     @NotNull
     @SuppressWarnings("unchecked")
     public static <D extends CallableDescriptor> Set<D> getAllOverriddenDescriptors(@NotNull D f) {
@@ -481,7 +484,7 @@ public class DescriptorUtils {
         if (result.contains(current)) return;
         for (CallableDescriptor callableDescriptor : current.getOriginal().getOverriddenDescriptors()) {
             @SuppressWarnings("unchecked")
-            D descriptor = (D) callableDescriptor;
+            D descriptor = (D) callableDescriptor.getOriginal();
             collectAllOverriddenDescriptors(descriptor, result);
             result.add(descriptor);
         }
diff --git a/core/descriptors/src/org/jetbrains/kotlin/resolve/OverridingUtil.java b/core/descriptors/src/org/jetbrains/kotlin/resolve/OverridingUtil.java
index c96d2e20cbc..80a9bf027f1 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/resolve/OverridingUtil.java
+++ b/core/descriptors/src/org/jetbrains/kotlin/resolve/OverridingUtil.java
@@ -119,7 +119,7 @@ public class OverridingUtil {
 
         CallableDescriptor originalG = g.getOriginal();
         for (D overriddenFunction : DescriptorUtils.getAllOverriddenDescriptors(f)) {
-            if (DescriptorEquivalenceForOverrides.INSTANCE.areEquivalent(originalG, overriddenFunction.getOriginal())) return true;
+            if (DescriptorEquivalenceForOverrides.INSTANCE.areEquivalent(originalG, overriddenFunction)) return true;
         }
         return false;
     }