diff -r 5c70d1c27a2e -r 0f9bae334ac6 src/Pure/ML/ml_process.scala
--- a/src/Pure/ML/ml_process.scala	Sat Nov 01 00:04:57 2025 +0100
+++ b/src/Pure/ML/ml_process.scala	Sat Nov 01 13:56:39 2025 +0100
@@ -135,7 +135,7 @@
     { args =>
       var dirs: List[Path] = Nil
       var eval_args: List[String] = Nil
-      var logic = Isabelle_System.getenv("ISABELLE_LOGIC")
+      var logic = Isabelle_System.default_logic()
       var modes: List[String] = Nil
       var options = Options.init()