$ git diff
diff --git a/scrutinizer.scm b/scrutinizer.scm
index c5d71bf..40b32aa 100755
--- a/scrutinizer.scm
+++ b/scrutinizer.scm
@@ -599,8 +599,9 @@
                         (b (assq var e)) )
                    (when (and type (not b)
                               (not (or (eq? type 'deprecated)
-                                        (and (= 2 (length type))
-                                             (eq? (car type) 'deprecated))))
+                                        (and (pair? type)
+                                             (eq? (car type) 'deprecated)
+                                             (= 2 (length type)))))
                               (not (match-types type rt typeenv)))
                      ((if strict-variable-types report-error report)
                       loc