mor robust;

--- a/src/Pure/System/classpath.scala	Wed Jul 27 09:27:40 2022 +0200
+++ b/src/Pure/System/classpath.scala	Wed Jul 27 11:00:09 2022 +0200
@@ -26,7 +26,7 @@
       for {
         s <- space_explode(JFile.pathSeparatorChar, System.getProperty("java.class.path", ""))
         if s.nonEmpty
-      } yield new JFile(s)
+      } yield File.absolute(new JFile(s))
 
     val jar_files1 =
       jar_files.flatMap(start => File.find_files(start, _.getName.endsWith(".jar")))