--- a/src/Pure/Tools/main.scala Thu Sep 05 21:11:16 2013 +0200
+++ b/src/Pure/Tools/main.scala Thu Sep 05 21:37:32 2013 +0200
@@ -47,10 +47,11 @@
if (!(new JFile(isabelle_home)).isDirectory)
error("Bad Isabelle home directory: " + quote(isabelle_home))
- System.setProperty("cygwin.root", isabelle_home + "\\contrib\\cygwin")
+ val cygwin_root = isabelle_home + "\\contrib\\cygwin"
+ if ((new JFile(cygwin_root)).isDirectory)
+ System.setProperty("cygwin.root", cygwin_root)
- val uninitialized_file =
- new JFile(isabelle_home, "contrib\\cygwin\\isabelle\\uninitialized")
+ val uninitialized_file = new JFile(cygwin_root, "isabelle\\uninitialized")
val uninitialized = uninitialized_file.isFile && uninitialized_file.delete
if (uninitialized) Some(isabelle_home) else None