1 files changed, 2 insertions, 1 deletions
diff --git a/diff-lib.c b/diff-lib.c
index 2e09500..b379759 100644
--- a/diff-lib.c
+++ b/diff-lib.c
@@ -379,7 +379,8 @@ static void do_oneway_diff(struct unpack_trees_options *o,
 	if (cached && idx && ce_stage(idx)) {
 		struct diff_filepair *pair;
 		pair = diff_unmerge(&revs->diffopt, idx->name);
-		fill_filespec(pair->one, idx->sha1, idx->ce_mode);
+		if (tree)
+			fill_filespec(pair->one, tree->sha1, tree->ce_mode);
 		return;
 	}