tuned;

--- a/src/Pure/Tools/main.scala	Fri Aug 21 23:27:52 2015 +0200
+++ b/src/Pure/Tools/main.scala	Sat Aug 22 11:32:34 2015 +0200
@@ -52,8 +52,7 @@
           else {
             system_dialog.title("Isabelle build (" +
               Isabelle_System.getenv("ML_IDENTIFIER") + " / " +
-              "jdk-" + Platform.jvm_version + "_" +
-              Isabelle_System.getenv("ISABELLE_JAVA_PLATFORM") + ")")
+              "jdk-" + Platform.jvm_version + "_" + Platform.jvm_platform + ")")
             system_dialog.echo("Build started for Isabelle/" + session + " ...")
 
             val (out, rc) =