[isabelle-dev] Failed to compile sources

[Lawrence Paulson]

What am I doing wrong? "isabelle build HOL" is the same.
Larry

~/isabelle/Repos/src/HOL: isabelle build 
### Building Isabelle/Scala layer ...
Changed files:
  Concurrent/simple_thread.scala
  General/exn.scala
  General/file.scala
  General/graph.scala
  General/linear_set.scala
  General/path.scala
  General/position.scala
  General/pretty.scala
  General/properties.scala
  General/scan.scala
  General/sha1.scala
  General/symbol.scala
  Isar/outer_syntax.scala
  Isar/parse.scala
  Isar/token.scala
  PIDE/command.scala
  PIDE/document.scala
  PIDE/isabelle_markup.scala
  PIDE/markup_tree.scala
  PIDE/protocol.scala
  PIDE/text.scala
  System/build.scala
  System/command_line.scala
  System/gui_setup.scala
  System/isabelle_process.scala
  System/isabelle_system.scala
  System/main.scala
  System/options.scala
  System/session.scala
  System/standard_system.scala
  System/system_channel.scala
  Thy/thy_header.scala
  Thy/thy_info.scala
  Thy/thy_load.scala
  Thy/thy_syntax.scala
  library.scala
System/command_line.scala:29: error: not found: value sys
    sys.exit(rc)
    ^
System/isabelle_system.scala:53: error: not found: value sys
        val env0 = sys.env + ("ISABELLE_JDK_HOME" -> standard_system.this_jdk_home())
                   ^
System/gui_setup.scala:65: error: not found: value sys
      case ButtonClicked(`ok`) => sys.exit(0)
                                  ^
System/main.scala:28: error: not found: value sys
    sys.exit(rc)
    ^
four errors found
Failed to compile sources
~/isabelle/Repos/src/HOL: hg id
fd50596bf78b tip