src/HOL/Tools/Nitpick/kodkod.ML

                   Error ("Unknown error", js)
               else
                 Normal (ps, js, first_error)
             end
         in remove_temporary_files (); outcome end
+        handle exn => (remove_temporary_files (); Exn.reraise exn)
       end
   end
 
 val cached_outcome =
   Synchronized.var "Kodkod.cached_outcome"