if (fix_thin_pack) {
                struct sha1file *f;
                unsigned char read_sha1[20], tail_sha1[20];
-               char msg[48];
+               struct strbuf msg = STRBUF_INIT;
                int nr_unresolved = nr_deltas - nr_resolved_deltas;
                int nr_objects_initial = nr_objects;
                if (nr_unresolved <= 0)
                                   * sizeof(*objects));
                f = sha1fd(output_fd, curr_pack);
                fix_unresolved_deltas(f, nr_unresolved);
-               sprintf(msg, _("completed with %d local objects"),
-                       nr_objects - nr_objects_initial);
-               stop_progress_msg(&progress, msg);
+               strbuf_addf(&msg, _("completed with %d local objects"),
+                           nr_objects - nr_objects_initial);
+               stop_progress_msg(&progress, msg.buf);
+               strbuf_release(&msg);
                sha1close(f, tail_sha1, 0);
                hashcpy(read_sha1, pack_sha1);
                fixup_pack_header_footer(output_fd, pack_sha1,