(gud-sdb-marker-filter): start may be nil, so check it

with numberp before using it.

diff --git a/lisp/gud.el b/lisp/gud.el
index 0f8776f3529eed577744862e6c94a29bbc1c1ad2..e7a43647a7e11869d9666ab8d5402a5303b553c3 100644 (file)
--- a/lisp/gud.el
+++ b/lisp/gud.el
@@ -454,7 +454,7 @@ available with older versions of GDB."
     ;; Otherwise clear gud-marker-acc. to avoid an
     ;; unnecessary concat when this function runs next.
     (setq gud-marker-acc 
-         (if (= start (length gud-marker-acc))
+         (if (and (numberp start) (= start (length gud-marker-acc)))
              (substring gud-marker-acc start)
            nil)))
   string)