1 files changed, 2 insertions, 1 deletions

diff --git a/lisp/progmodes/grep.el b/lisp/progmodes/grep.el
index 04fcae78ea6..8efa48aaa48 100644
--- a/lisp/progmodes/grep.el
+++ b/lisp/progmodes/grep.el
@@ -527,7 +527,8 @@ This command uses a special history list for its arguments, so you can
 easily repeat a find command."
   (interactive
    (progn
-     (unless grep-find-command
+     (unless (and grep-command
+                  (or (not grep-use-null-device) (eq grep-use-null-device t)))
        (grep-compute-defaults))
      (if grep-find-command
          (list (read-from-minibuffer "Run find (like this): "