diff -r 8664433956b3 -r df49ca5da9d0 src/Pure/Admin/build_spass.scala
--- a/src/Pure/Admin/build_spass.scala	Sat Feb 27 17:33:40 2021 +0100
+++ b/src/Pure/Admin/build_spass.scala	Sat Feb 27 18:04:29 2021 +0100
@@ -94,12 +94,13 @@
 
       /* install */
 
-      File.copy(build_dir + Path.basic("LICENCE"), component_dir + Path.basic("LICENSE"))
+      Isabelle_System.copy_file(build_dir + Path.basic("LICENCE"),
+        component_dir + Path.basic("LICENSE"))
 
       val install_files = List("SPASS")
       for (name <- install_files ::: install_files.map(_ + ".exe")) {
         val path = build_dir + Path.basic(name)
-        if (path.is_file) File.copy(path, platform_dir)
+        if (path.is_file) Isabelle_System.copy_file(path, platform_dir)
       }