write_locked_index(): add flag to avoid writing unchanged index

diff --git a/merge-recursive.c b/merge-recursive.c
index 6ff971f9a2a8e251b8762d75214697698e2d1ce6..2f232ad3b40e6a94ea78bd856a4ea2deaaf1d468 100644 (file)
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -2218,11 +2218,13 @@ int merge_recursive_generic(struct merge_options *o,
        hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
        clean = merge_recursive(o, head_commit, next_commit, ca,
                        result);
-       if (clean < 0)
+       if (clean < 0) {
+               rollback_lock_file(&lock);
                return clean;
+       }
 
-       if (active_cache_changed &&
-           write_locked_index(&the_index, &lock, COMMIT_LOCK))
+       if (write_locked_index(&the_index, &lock,
+                              COMMIT_LOCK | SKIP_IF_UNCHANGED))
                return err(o, _("Unable to write index."));
 
        return clean ? 0 : 1;