check comint-input-ring-file-name for the empty string too.

diff --git a/lisp/shell.el b/lisp/shell.el
index 02d00fd72e26bf90be529d6d536ada07501cc317..33e10847616682a325bfd34fab75b40942168fd3 100644 (file)
--- a/lisp/shell.el
+++ b/lisp/shell.el
@@ -340,7 +340,8 @@ buffer."
              (cond ((string-equal shell "bash") "~/.bash_history")
                    ((string-equal shell "ksh") "~/.sh_history")
                    (t "~/.history"))))
-    (if (equal (file-truename comint-input-ring-file-name) "/dev/null")
+    (if (or (equal comint-input-ring-file-name "")
+           (equal (file-truename comint-input-ring-file-name) "/dev/null"))
        (setq comint-input-ring-file-name nil))
     (setq shell-dirstack-query
          (if (string-match "^k?sh$" shell) "pwd" "dirs")))