(grep): Fix previous change.

1 files changed, 7 insertions, 5 deletions

diff --git a/lisp/progmodes/compile.el b/lisp/progmodes/compile.el
index c74c2c570ca..6929e92708b 100644
--- a/lisp/progmodes/compile.el
+++ b/lisp/progmodes/compile.el
@@ -556,19 +556,21 @@ This command uses a special history list for its arguments, so you can
 easily repeat a grep command.
 
 A prefix argument says to default the argument based upon the current
-tag the cursor is over."
+tag the cursor is over, substituting it into the last grep command
+in the grep command history (or into `grep-command'
+if that history list is empty)."
   (interactive
-   (let (grep-default)
-     (when (and current-prefix-arg grep-history)
+   (let (grep-default (arg current-prefix-arg))
+     (when arg
        (let* ((tag-default
                (funcall (or find-tag-default-function
                             (get major-mode 'find-tag-default-function)
                             ;; We use grep-tag-default instead of
                             ;; find-tag-default, to avoid loading etags.
                             'grep-tag-default))))
-         (setq grep-default (car grep-history))
+         (setq grep-default (or (car grep-history) grep-command))
          ;; Replace the thing matching for with that around cursor
-         (if (string-match "[^ ]+\\s +\\(-[^ ]+\\)*\\s *\\(\"[^\"]+\"\\|[^ ]+\\)" grep-default)
+         (if (string-match "[^ ]+\\s +\\(-[^ ]+\\s +\\)*\\(\"[^\"]+\"\\|[^ ]+\\)" grep-default)
              (setq grep-default (replace-match tag-default t t
                                                grep-default 2)))))
      (list (read-from-minibuffer "Run grep (like this): "