diff -r a213dd3c0b29 -r b525f783b784 src/Pure/Admin/component_vampire.scala
--- a/src/Pure/Admin/component_vampire.scala	Thu Mar 28 11:29:25 2024 +0100
+++ b/src/Pure/Admin/component_vampire.scala	Thu Mar 28 11:35:39 2024 +0100
@@ -48,10 +48,7 @@
 
       /* platform */
 
-      val platform_name =
-        proper_string(Isabelle_System.getenv("ISABELLE_PLATFORM64")) getOrElse
-          error("Missing ISABELLE_PLATFORM64")
-
+      val platform_name = Isabelle_Platform.self.ISABELLE_PLATFORM()
       val platform_dir =
         Isabelle_System.make_directory(component_dir.path + Path.basic(platform_name))