diff --git a/gradle/configure-source-sets.gradle b/gradle/configure-source-sets.gradle
index 56a2239e53..3bcf9b977f 100644
--- a/gradle/configure-source-sets.gradle
+++ b/gradle/configure-source-sets.gradle
@@ -112,6 +112,7 @@ kotlin {
                     languageVersion = rootProject.ext.kotlin_lv_override
                     freeCompilerArgs += "-Xsuppress-version-warnings"
                 }
+                freeCompilerArgs += "-Xexpect-actual-classes"
             }
         }
         compilations.main {