Rollback when freelist == pgidNoFreelist causes panic (index out of range) about bbolt HOT 5 CLOSED

// meta retrieves the current meta page reference.
func (db *DB) meta() *meta {
        // We have to return the meta with the highest txid which doesn't fail
        // validation. Otherwise, we can cause errors when in fact the database is
        // in a consistent state. metaA is the one with the higher txid.

        fmt.Printf("bolt: db: meta: meta0: %T,%v, meta1: %T,%v, db.meta0.txid: %T,%v, db.meta1.txid: %T,%v\n",
                db.meta0,db.meta0,db.meta1,db.meta1,db.meta0.txid,db.meta0.txid,db.meta1.txid,db.meta1.txid)

        metaA := db.meta0
        metaB := db.meta1
        if db.meta1.txid > db.meta0.txid {
                metaA = db.meta1
                metaB = db.meta0
        }

        // Use higher meta page if valid. Otherwise fallback to previous, if valid.
        if err := metaA.validate(); err == nil {
                return metaA
        } else if err := metaB.validate(); err == nil {
                return metaB
        }

        // This should never be reached, because both meta1 and meta0 were validated
        // on mmap() and we do fsync() on every write.
        panic("bolt.DB.meta(): invalid meta pages")
}

func (tx *Tx) rollback() {
        if tx.db == nil {
                return
        }
        if tx.writable {
                tx.db.freelist.rollback(tx.meta.txid)
                currFreelist := tx.db.meta().freelist
                if currFreelist != pgidNoFreelist {
                        tx.db.freelist.reload(tx.db.page(currFreelist))
                }
        }
        tx.close()
}