static const char *diff_abbrev_oid(const struct object_id *oid, int abbrev)
{
if (startup_info->have_repository)
- return find_unique_abbrev(oid->hash, abbrev);
+ return find_unique_abbrev(oid, abbrev);
else {
char *hex = oid_to_hex(oid);
if (abbrev < 0)