diff -r 878a67422fb4 -r f178475f274d src/Pure/Admin/component_mlton.scala
--- a/src/Pure/Admin/component_mlton.scala	Mon Feb 03 13:12:44 2025 +0100
+++ b/src/Pure/Admin/component_mlton.scala	Mon Feb 03 14:15:37 2025 +0100
@@ -13,47 +13,47 @@
 object Component_MLton {
   /* platform information */
 
-  sealed case class Download_Platform(platform_name: String, download_name: String) {
-    def download(base_url: String, version: String): String =
-      Url.append_path(base_url, version + "." + download_name)
-  }
+  sealed case class Download_Platform(platform_name: String, download_name: String)
 
   val platforms: List[Download_Platform] =
     List(
-      Download_Platform("x86_64-darwin", "amd64-darwin-16.7-gmp-static.tgz"),
-      Download_Platform("x86_64-linux", "amd64-linux-glibc2.19-gmp-static.tgz"))
+      Download_Platform("arm64-darwin", "arm64-darwin.macos-14_gmp-static.tgz"),
+      Download_Platform("x86_64-darwin", "amd64-darwin.macos-13_gmp-static.tgz"),
+      Download_Platform("x86_64-linux", "amd64-linux.ubuntu-20.04_static.tgz"))
 
 
   /* build mlton */
 
-  val default_url = "https://projects.laas.fr/tina/software"
-  val default_version = "mlton-20210117-1"
+  val default_url = "https://master.dl.sourceforge.net/project/mlton/mlton"
+  val default_url_suffix = "?viasf=1"
+  val default_version = "20241230"
+  val default_variant = "mlton-20241230-1"
 
   def build_mlton(
     base_url: String = default_url,
+    base_url_suffix: String = default_url_suffix,
     version: String = default_version,
+    variant: String = default_variant,
     target_dir: Path = Path.current,
     progress: Progress = new Progress
   ): Unit = {
     val component_dir =
-      Components.Directory(target_dir + Path.basic(version)).create(progress = progress)
+      Components.Directory(target_dir + Path.basic(variant)).create(progress = progress)
 
 
     /* download executables */
 
     for (platform <- platforms) {
       Isabelle_System.with_tmp_dir("download") { download_dir =>
-        val download = platform.download(base_url, version)
-
-        val archive_name =
-          Url.get_base_name(download) getOrElse
-            error("Malformed download URL " + quote(download))
+        val archive_name = platform.download_name
         val archive_path = download_dir + Path.basic(archive_name)
 
         val platform_dir = component_dir.path + Path.explode(platform.platform_name)
         Isabelle_System.make_directory(platform_dir)
 
-        Isabelle_System.download_file(download, archive_path, progress = progress)
+        val url =
+          Url.append_path(base_url, version) + "/" + variant + "." + archive_name + base_url_suffix
+        Isabelle_System.download_file(url, archive_path, progress = progress)
         Isabelle_System.extract(archive_path, platform_dir, strip = true)
         Isabelle_System.copy_file(platform_dir + Path.basic("LICENSE"), platform_dir.expand.dir)
       }
@@ -63,8 +63,10 @@
   /* settings */
 
     component_dir.write_settings("""
-if [ -d "$COMPONENT/$ISABELLE_PLATFORM64" ]; then
-  ISABELLE_MLTON="$COMPONENT/$ISABELLE_PLATFORM64/bin/mlton"
+ISABELLE_MLTON_HOME="$COMPONENT"
+
+if [ -d "$ISABELLE_MLTON_HOME/${ISABELLE_APPLE_PLATFORM64:-$ISABELLE_PLATFORM64}" ]; then
+  ISABELLE_MLTON="$ISABELLE_MLTON_HOME/${ISABELLE_APPLE_PLATFORM64:-$ISABELLE_PLATFORM64}/bin/mlton"
   case "$ISABELLE_PLATFORM_FAMILY" in
     linux*)
       ISABELLE_MLTON_OPTIONS="-pi-style npi"
@@ -80,9 +82,9 @@
     /* README */
 
     File.write(component_dir.README,
-      """This distribution of MLton has been taken from the TINA project
-https://projects.laas.fr/tina/software.php using following downloads:""" +
-        platforms.map(_.download(base_url, version)).mkString("\n\n  ", "\n  ", "\n\n") +
+      """This is the MLton SML compiler from
+https://sourceforge.net/projects/mlton using following downloads:""" +
+        platforms.map(_.download_name).mkString("\n\n  ", "\n  ", "\n\n") +
 """Windows and Linux ARM are unsupported.
 
 
@@ -97,29 +99,35 @@
     Isabelle_Tool("component_mlton", "build component for MLton", Scala_Project.here,
       { args =>
         var target_dir = Path.current
+        var base_url_suffix = default_url_suffix
         var base_url = default_url
         var version = default_version
+        var variant = default_variant
 
         val getopts = Getopts("""
 Usage: isabelle component_mlton [OPTIONS]
 
   Options are:
     -D DIR       target directory (default ".")
+    -S SUFFIX    download URL suffix (default: """" + default_url_suffix + """")
     -U URL       download URL (default: """" + default_url + """")
     -V VERSION   version (default: """" + default_version + """")
+    -W VARIANT   variant (default: """" + default_variant + """")
 
   Build component for MLton compiler.
 """,
           "D:" -> (arg => target_dir = Path.explode(arg)),
+          "S:" -> (arg => base_url_suffix = arg),
           "U:" -> (arg => base_url = arg),
-          "V:" -> (arg => version = arg))
+          "V:" -> (arg => version = arg),
+          "W:" -> (arg => variant = arg))
 
         val more_args = getopts(args)
         if (more_args.nonEmpty) getopts.usage()
 
         val progress = new Console_Progress()
 
-        build_mlton(base_url = base_url, version = version, target_dir = target_dir,
-          progress = progress)
+        build_mlton(base_url = base_url, base_url_suffix = base_url_suffix, version = version,
+          variant = variant, target_dir = target_dir, progress = progress)
       })
 }