mergetool: don't require a work tree for --tool-help

diff --git a/git-p4.py b/git-p4.py
index 4ee673994be6d4dca177dc054cb8a6bc6ed1f253..773cafcd89b6cd89d413e3d51056c4aaf53c1f2c 100755 (executable)
--- a/git-p4.py
+++ b/git-p4.py
@@ -3086,7 +3086,7 @@ def rebase(self):
         print "Rebasing the current branch onto %s" % upstream
         oldHead = read_pipe("git rev-parse HEAD").strip()
         system("git rebase %s" % upstream)
-        system("git diff-tree --stat --summary -M %s HEAD" % oldHead)
+        system("git diff-tree --stat --summary -M %s HEAD --" % oldHead)
         return True
 
 class P4Clone(P4Sync):