diff -r 5d44c6a7bd7b -r 0ddb5de0506e src/Pure/System/progress.scala
--- a/src/Pure/System/progress.scala	Mon Jun 28 20:52:31 2021 +0200
+++ b/src/Pure/System/progress.scala	Wed Jun 30 11:35:07 2021 +0200
@@ -7,6 +7,7 @@
 package isabelle
 
 
+import java.util.{Map => JMap}
 import java.io.{File => JFile}
 
 
@@ -50,7 +51,7 @@
 
   def bash(script: String,
     cwd: JFile = null,
-    env: Map[String, String] = Isabelle_System.settings(),
+    env: JMap[String, String] = Isabelle_System.settings(),
     redirect: Boolean = false,
     echo: Boolean = false,
     watchdog: Time = Time.zero,