diff -r f19e5837ad69 -r 5c6955f487e5 src/Tools/Code/code_preproc.ML
--- a/src/Tools/Code/code_preproc.ML	Fri Mar 16 14:46:13 2012 +0100
+++ b/src/Tools/Code/code_preproc.ML	Fri Mar 16 18:20:12 2012 +0100
@@ -525,8 +525,8 @@
   end;
 
 val _ =
-  Outer_Syntax.improper_command "print_codeproc" "print code preprocessor setup"
-  Keyword.diag (Scan.succeed
+  Outer_Syntax.improper_command @{command_spec "print_codeproc"} "print code preprocessor setup"
+    (Scan.succeed
       (Toplevel.no_timing o Toplevel.unknown_theory o Toplevel.keep
         (print_codeproc o Toplevel.theory_of)));