diff --git a/builtin/diff-index.c b/builtin/diff-index.c
index 1c737f7..ce15b23 100644
--- a/builtin/diff-index.c
+++ b/builtin/diff-index.c
@@ -43,7 +43,7 @@
 		usage(diff_cache_usage);
 	if (!cached) {
 		setup_work_tree();
-		if (read_cache_preload(rev.diffopt.pathspec.raw) < 0) {
+		if (read_cache_preload(&rev.diffopt.pathspec) < 0) {
 			perror("read_cache_preload");
 			return -1;
 		}