// TARGET_BACKEND: JVM_IR // JVM_TARGET: 1.8 // FILE: A.java public interface A { default String foo() { return "OK"; } } // FILE: B.java public interface B extends A {} // FILE: C.java public interface C extends A {} // FILE: test.kt class Adapter : B, C class D(val adapter: Adapter) : B by adapter, C by adapter fun box(): String { val adapter = Adapter() val d = D(adapter) return d.foo() }