Kotlin no longer compiled with JVM 1.8 target


It seems Kotlin is now compiled on codingame with JVM 1.6 target instead of JVM 1.8, probably since the last Kotlin 1.3 update.

Code that was working last summer using java 8 features (Comparator.comparingInt(…)) no longer compiles on codingame, and the error message indicates that a JVM 1.6 target is used :

error: calls to static methods in Java interfaces are prohibited in JVM target 1.6. Recompile with ‘-jvm-target 1.8’.