Fallback to Any type in case supertypes are empty

This can happen e.g. if all supertypes were on the cycle (A : B, B : A)
-- then SupertypesLoopChecker will cut all supertypes that are on cycle,
leaving set of supertypes empty.

Some clients in the compiler are not ready to work with empty list of
supertypes -- notably, CommonSupertypes.

^KT-23029 Fixed

compiler/testData/diagnostics/tests/cast/IsRecursionSustainable.txt

@@ -5,12 +5,21 @@ public fun test(/*0*/ f: SelfR<kotlin.String>): kotlin.Boolean
 
 public open class RecA</*0*/ T> {
     public constructor RecA</*0*/ T>()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public open class RecB</*0*/ T> {
     public constructor RecB</*0*/ T>()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public open class SelfR</*0*/ T> {
     public constructor SelfR</*0*/ T>()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }

compiler/testData/diagnostics/tests/cyclicHierarchy/classIndirectlyInheritsNested.txt

@@ -2,6 +2,9 @@ package
 
 public open class C {
     public constructor C()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public open class CC {
         public constructor CC()
@@ -13,4 +16,7 @@ public open class C {
 
 public open class D {
     public constructor D()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }

compiler/testData/diagnostics/tests/cyclicHierarchy/classInheritsNested.txt

@@ -2,6 +2,9 @@ package
 
 public open class E {
     public constructor E()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public open class EE {
         public constructor EE()

compiler/testData/diagnostics/tests/cyclicHierarchy/commonSupertypeForCyclicAndUsualTypes.kt

@@ -0,0 +1,8 @@
+open class A : <!CYCLIC_INHERITANCE_HIERARCHY!>B<!>()
+open class B : <!CYCLIC_INHERITANCE_HIERARCHY!>A<!>()
+
+fun <T> select(vararg xs: T): T = xs[0]
+
+fun foo() {
+    val <!UNUSED_VARIABLE!>x<!> = select(A(), B(), "foo")
+}

compiler/testData/diagnostics/tests/cyclicHierarchy/commonSupertypeForCyclicAndUsualTypes.txt

@@ -0,0 +1,18 @@
+package
+
+public fun foo(): kotlin.Unit
+public fun </*0*/ T> select(/*0*/ vararg xs: T /*kotlin.Array<out T>*/): T
+
+public open class A {
+    public constructor A()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public open class B {
+    public constructor B()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/cyclicHierarchy/commonSupertypeForCyclicTypes.kt

@@ -0,0 +1,8 @@
+open class A : <!CYCLIC_INHERITANCE_HIERARCHY!>B<!>()
+open class B : <!CYCLIC_INHERITANCE_HIERARCHY!>A<!>()
+
+fun <T> select(vararg xs: T): T = xs[0]
+
+fun foo() {
+    select(A(), B())
+}

compiler/testData/diagnostics/tests/cyclicHierarchy/commonSupertypeForCyclicTypes.txt

@@ -0,0 +1,18 @@
+package
+
+public fun foo(): kotlin.Unit
+public fun </*0*/ T> select(/*0*/ vararg xs: T /*kotlin.Array<out T>*/): T
+
+public open class A {
+    public constructor A()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public open class B {
+    public constructor B()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/cyclicHierarchy/cyclicHierarchy.txt

@@ -25,19 +25,37 @@ public interface B : A {
 }
 
 public interface C {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public interface D {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public interface E {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public interface F {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public interface G : F {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public interface H : F {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }

compiler/testData/diagnostics/tests/cyclicHierarchy/javaJavaCycle.txt

@@ -3,7 +3,10 @@ package
 public fun foo(): kotlin.Unit
 
 public interface A {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
     public abstract fun getFoo(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public open class B {
@@ -13,14 +16,23 @@ public open class B {
     public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public/*package*/ interface B1 : B.B2 {
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
         public abstract override /*1*/ fun getFoo(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
     }
 
     public/*package*/ interface B2 {
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
         public abstract fun getFoo(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
     }
 
     public/*package*/ interface B3 {
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
         public abstract fun getFoo(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
     }
 }

compiler/testData/diagnostics/tests/cyclicHierarchy/javaJavaNested.txt

@@ -1,13 +1,22 @@
 package
 
 public interface A {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public interface B {
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
         public abstract fun getFoo(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
     }
 }
 
 public interface A0 {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public interface B {
         public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
@@ -19,7 +28,10 @@ public interface A0 {
 
 public open class B {
     public constructor B()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
     public open fun getFoo(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public open class C {
         public constructor C()
@@ -32,5 +44,8 @@ public open class B {
 
 public open class D {
     public constructor D()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
     public open fun getFoo(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }

compiler/testData/diagnostics/tests/cyclicHierarchy/javaKotlinJavaCycle.txt

@@ -1,13 +1,22 @@
 package
 
 public/*package*/ interface A {
+    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 {
     public abstract fun bar(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public/*package*/ interface C {
     public abstract fun baz(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }

compiler/testData/diagnostics/tests/cyclicHierarchy/kotlinJavaCycle.txt

@@ -2,10 +2,16 @@ package
 
 public/*package*/ open class J {
     public/*package*/ constructor J()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
     public/*package*/ open 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 K {
     public constructor K()
     public final fun bar(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }

compiler/testData/diagnostics/tests/cyclicHierarchy/kotlinJavaKotlinCycle.txt

@@ -2,15 +2,24 @@ package
 
 public open class I {
     public constructor I()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
     public final 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/*package*/ open class J {
     public/*package*/ constructor J()
     public/*package*/ open fun bar(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public open class K {
     public constructor K()
     public final fun baz(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }

compiler/testData/diagnostics/tests/cyclicHierarchy/kotlinJavaNestedCycle.txt

@@ -1,11 +1,17 @@
 package
 
 public interface ExceptionTracker {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public/*package*/ open class LockBasedStorageManager {
     public/*package*/ constructor LockBasedStorageManager()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
     @java.lang.Override public/*package*/ open 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/*package*/ interface ExceptionHandlingStrategy {
         public abstract fun bar(): kotlin.Unit
@@ -16,5 +22,8 @@ public/*package*/ open class LockBasedStorageManager {
 }
 
 public interface StorageManager {
+    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
 }

compiler/testData/diagnostics/tests/cyclicHierarchy/kt303.txt

@@ -4,9 +4,15 @@ public val x: kotlin.Int
 
 public open class Bar {
     public constructor Bar()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public open class Foo {
     public constructor Foo()
     public final val a: kotlin.Int = 1
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }

compiler/testData/diagnostics/tests/cyclicHierarchy/objectInheritsNested.txt

@@ -2,6 +2,9 @@ package
 
 public object A {
     private constructor A()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public interface I {
         public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
@@ -12,6 +15,9 @@ public object A {
 
 public object D {
     private constructor D()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public open class NestedD {
         public constructor NestedD()
@@ -23,10 +29,16 @@ public object D {
 
 public open class E {
     public constructor E()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
 public object G {
     private constructor G()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public open class NestedG {
         public constructor NestedG()
@@ -38,6 +50,9 @@ public object G {
 
 public object H {
     private constructor H()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public open class NestedH {
         public constructor NestedH()

compiler/testData/diagnostics/tests/cyclicHierarchy/twoClassesWithNestedCycle.txt

@@ -2,6 +2,9 @@ package
 
 public open class A {
     public constructor A()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public open class AA {
         public constructor AA()
@@ -13,6 +16,9 @@ public open class A {
 
 public open class B {
     public constructor B()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public open class BB {
         public constructor BB()

compiler/testData/diagnostics/tests/regressions/TypeParameterAsASupertype.txt

@@ -2,4 +2,7 @@ package
 
 public final class A</*0*/ T> {
     public constructor A</*0*/ T>()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }

compiler/testData/diagnostics/tests/typealias/cyclicInheritanceViaTypeAlias.txt

@@ -2,6 +2,9 @@ package
 
 public final class A {
     public constructor A()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 
     public open class Nested</*0*/ T> {
         public constructor Nested</*0*/ T>()
@@ -13,5 +16,8 @@ public final class A {
 
 public open class B {
     public constructor B()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 public typealias ANested</*0*/ T> = A.Nested<T>

compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java

@@ -4796,6 +4796,18 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                 doTest(fileName);
             }
 
+            @TestMetadata("commonSupertypeForCyclicAndUsualTypes.kt")
+            public void testCommonSupertypeForCyclicAndUsualTypes() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/cyclicHierarchy/commonSupertypeForCyclicAndUsualTypes.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("commonSupertypeForCyclicTypes.kt")
+            public void testCommonSupertypeForCyclicTypes() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/cyclicHierarchy/commonSupertypeForCyclicTypes.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("cyclicHierarchy.kt")
             public void testCyclicHierarchy() throws Exception {
                 String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/cyclicHierarchy/cyclicHierarchy.kt");

compiler/tests/org/jetbrains/kotlin/checkers/javac/DiagnosticsUsingJavacTestGenerated.java

@@ -4796,6 +4796,18 @@ public class DiagnosticsUsingJavacTestGenerated extends AbstractDiagnosticsUsing
                 doTest(fileName);
             }
 
+            @TestMetadata("commonSupertypeForCyclicAndUsualTypes.kt")
+            public void testCommonSupertypeForCyclicAndUsualTypes() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/cyclicHierarchy/commonSupertypeForCyclicAndUsualTypes.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("commonSupertypeForCyclicTypes.kt")
+            public void testCommonSupertypeForCyclicTypes() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/cyclicHierarchy/commonSupertypeForCyclicTypes.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("cyclicHierarchy.kt")
             public void testCyclicHierarchy() throws Exception {
                 String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/cyclicHierarchy/cyclicHierarchy.kt");

core/descriptors/src/org/jetbrains/kotlin/types/AbstractClassTypeConstructor.java

@@ -17,6 +17,7 @@
 package org.jetbrains.kotlin.types;
 
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns;
 import org.jetbrains.kotlin.descriptors.*;
 import org.jetbrains.kotlin.resolve.DescriptorUtils;
@@ -160,4 +161,14 @@ public abstract class AbstractClassTypeConstructor extends AbstractTypeConstruct
 
         return additionalNeighbours;
     }
+
+    @Nullable
+    @Override
+    protected KotlinType defaultSupertypeIfEmpty() {
+        if (KotlinBuiltIns.isSpecialClassWithNoSupertypes(this.getDeclarationDescriptor())) {
+            return null;
+        } else {
+            return getBuiltIns().getAnyType();
+        }
+    }
 }