Map Nothing to java.lang.Void

compiler/testData/codegen/box/typeMapping/nothing.kt

@@ -0,0 +1,5 @@
+fun box(): String {
+    // jet.Nothing should not be loaded here
+    val x = "" is Nothing
+    return "OK"
+}

compiler/testData/codegen/box/typeMapping/nullableNothing.kt

@@ -0,0 +1,6 @@
+
+fun box(): String {
+    // This used to be problematic because of an attempt to load jet/Nothing class
+    val x = "" is Nothing?
+    return "OK"
+}