src/Pure/Admin/component_hol_light.scala

       val offline_exe = offline_path.platform_exe
       val offline_dir = Isabelle_System.make_directory(tmp_dir + offline_path)
 
       Isabelle_System.copy_dir(hol_import_dir + offline_path, offline_dir, direct = true)
 
-      progress.bash("ocamlopt offline.ml -o offline",
+      progress.bash("ocamlc.opt offline.ml -o offline",
         cwd = offline_dir, echo = progress.verbose).check
       Isabelle_System.copy_file(offline_dir + offline_exe, platform_dir + offline_exe)
       File.set_executable(platform_dir + offline_exe)