1 files changed, 3 insertions, 0 deletions
diff --git a/diff.h b/diff.h
index 6616877ee5..2740421cfe 100644
--- a/diff.h
+++ b/diff.h
@@ -66,6 +66,9 @@ typedef void (*diff_format_fn_t)(struct diff_queue_struct *q,
 #define DIFF_OPT_DIRSTAT_CUMULATIVE  (1 << 19)
 #define DIFF_OPT_DIRSTAT_BY_FILE     (1 << 20)
 #define DIFF_OPT_ALLOW_TEXTCONV      (1 << 21)
+
+#define DIFF_OPT_SUBMODULE_LOG       (1 << 23)
+
 #define DIFF_OPT_TST(opts, flag)    ((opts)->flags & DIFF_OPT_##flag)
 #define DIFF_OPT_SET(opts, flag)    ((opts)->flags |= DIFF_OPT_##flag)
 #define DIFF_OPT_CLR(opts, flag)    ((opts)->flags &= ~DIFF_OPT_##flag)