Merge fix bits from jc/rev-list

diff --combined rev-list.c
index 1589400,b5de075..6cd83ed
--- 1/rev-list.c
--- 2/rev-list.c
+++ b/rev-list.c
@@@ -256,8 -256,8 +256,8 @@@ static void show_commit_list(struct com
                die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
        }
        while (objects) {
 -              /* An object with name "foo\n0000000000000000000000000000000000000000"
 -               * can be used confuse downstream git-pack-objects very badly.
 +              /* An object with name "foo\n0000000..." can be used to
 +               * confuse downstream git-pack-objects very badly.
                 */
                const char *ep = strchr(objects->name, '\n');
                if (ep) {
@@@ -440,8 -440,10 +440,10 @@@ static void mark_edge_parents_uninteres
                if (!(parent->object.flags & UNINTERESTING))
                        continue;
                mark_tree_uninteresting(parent->tree);
-               if (edge_hint)
+               if (edge_hint && !(parent->object.flags & SHOWN)) {
+                       parent->object.flags |= SHOWN;
                        printf("-%s\n", sha1_to_hex(parent->object.sha1));
+               }
        }
  }