src/Pure/ML_Bootstrap.thy

--- a/src/Pure/ML_Bootstrap.thy	Sat Apr 09 14:52:10 2016 +0200
+++ b/src/Pure/ML_Bootstrap.thy	Sat Apr 09 16:16:05 2016 +0200
@@ -9,7 +9,12 @@
 begin
 
 setup \<open>Context.theory_map ML_Env.init_bootstrap\<close>
-SML_import \<open>structure Thread_Data = Thread_Data_Virtual\<close>
+
+SML_import \<open>
+structure Output_Primitives = Output_Primitives_Virtual;
+structure Thread_Data = Thread_Data_Virtual;
+\<close>
+
 setup \<open>Config.put_global ML_Env.SML_environment true\<close>
 
 end