diff --git a/convert.lisp b/convert.lisp
index 4cb503e..cc6de38 100644
--- a/convert.lisp
+++ b/convert.lisp
@@ -20,6 +20,7 @@
 ;;; Program entry point
 (defun convert (platform dot-file)
   "Parse Simgrid platform then write it into a dot file."
+  (setf *hosts* nil *links* nil) ; Be sure to clear hosts and links
   (let ((xml-parser (make-instance 'xml-parser-state
 				                 :seed (cons 0 0)
                                  :new-element-hook #'handle-element)))