diff --git a/ref-filter.c b/ref-filter.c
index 5550a0d34c..e0b8cd3ed8 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -2239,12 +2239,14 @@ static void reach_filter(struct ref_array *array,
 {
 	struct rev_info revs;
 	int i, old_nr;
-	struct commit **to_clear = xcalloc(sizeof(struct commit *), array->nr);
+	struct commit **to_clear;
 	struct commit_list *cr;
 
 	if (!check_reachable)
 		return;
 
+	to_clear = xcalloc(sizeof(struct commit *), array->nr);
+
 	repo_init_revisions(the_repository, &revs, NULL);
 
 	for (i = 0; i < array->nr; i++) {