src/Pure/System/gui_setup.scala

     if (Platform.is_windows)
       text.append("Cygwin root: " + Cygwin.check_root() + "\n")
     text.append("JVM name: " + Platform.jvm_name + "\n")
     text.append("JVM platform: " + Platform.jvm_platform + "\n")
     try {
-      val isabelle_system = new Isabelle_System
+      val isabelle_system = Isabelle_System.default
       text.append("ML platform: " + isabelle_system.getenv("ML_PLATFORM") + "\n")
       text.append("Isabelle platform: " + isabelle_system.getenv("ISABELLE_PLATFORM") + "\n")
       val platform64 = isabelle_system.getenv("ISABELLE_PLATFORM64")
       if (platform64 != "") text.append("Isabelle platform (64 bit): " + platform64 + "\n")
       text.append("Isabelle home: " + isabelle_system.getenv("ISABELLE_HOME") + "\n")