diff --git a/src/Pure/System/isabelle_platform.scala b/src/Pure/System/isabelle_platform.scala
--- a/src/Pure/System/isabelle_platform.scala
+++ b/src/Pure/System/isabelle_platform.scala
@@ -1,56 +1,55 @@
 /*  Title:      Pure/System/isabelle_platform.scala
     Author:     Makarius
 
 General hardware and operating system type for Isabelle system tools.
 */
 
 package isabelle
 
 
 object Isabelle_Platform
 {
   val settings: List[String] =
     List(
       "ISABELLE_PLATFORM_FAMILY",
       "ISABELLE_PLATFORM32",
       "ISABELLE_PLATFORM64",
       "ISABELLE_WINDOWS_PLATFORM32",
       "ISABELLE_WINDOWS_PLATFORM64")
 
   def local(): Isabelle_Platform =
     new Isabelle_Platform(settings.map(a => (a, Isabelle_System.getenv(a))))
 
   def remote(ssh: SSH.Session): Isabelle_Platform =
   {
     val script =
       File.read(Path.explode("~~/lib/scripts/isabelle-platform")) + "\n" +
       settings.map(a => "echo \"" + Bash.string(a) + "=$" + Bash.string(a) + "\"").mkString("\n")
     val result = ssh.execute("bash -c " + Bash.string(script)).check
-    val values =
+    new Isabelle_Platform(
       result.out_lines.map(line =>
         space_explode('=', line) match {
           case List(a, b) => (a, b)
           case _ => error("Bad output: " + quote(result.out))
-        })
-    new Isabelle_Platform(values)
+        }))
   }
 }
 
-class Isabelle_Platform private(values: List[(String, String)])
+class Isabelle_Platform private(val settings: List[(String, String)])
 {
   private def get(name: String): String =
-    values.collectFirst({ case (a, b) if a == name => b }).
+    settings.collectFirst({ case (a, b) if a == name => b }).
       getOrElse(error("Bad platform settings variable: " + quote(name)))
 
   val ISABELLE_PLATFORM_FAMILY: String = get("ISABELLE_PLATFORM_FAMILY")
   val ISABELLE_PLATFORM32: String = get("ISABELLE_PLATFORM32")
   val ISABELLE_PLATFORM64: String = get("ISABELLE_PLATFORM64")
   val ISABELLE_WINDOWS_PLATFORM32: String = get("ISABELLE_WINDOWS_PLATFORM32")
   val ISABELLE_WINDOWS_PLATFORM64: String = get("ISABELLE_WINDOWS_PLATFORM64")
 
   val is_linux: Boolean = ISABELLE_PLATFORM_FAMILY == "linux"
   val is_macos: Boolean = ISABELLE_PLATFORM_FAMILY == "macos"
   val is_windows: Boolean = ISABELLE_PLATFORM_FAMILY == "windows"
 
   override def toString: String = ISABELLE_PLATFORM_FAMILY
 }