ethereum/go-ethereum · error

not supported

Error message

not supported

What it means

ProofSet is a tiny in-memory map used by trie proof verification (VerifyRange/VerifyProof): it is a read-collecting fake database that only supports Has/Put/Get. DeleteRange panics because a proof verification never bulk-deletes — calling it means the ProofSet was passed to an API that expects a real KeyValueStore writer.

Source

Thrown at trie/trienode/proof.go:73

	db.nodes[keystr] = common.CopyBytes(value)
	db.order = append(db.order, keystr)
	db.dataSize += len(value)

	return nil
}

// Delete removes a node from the set
func (db *ProofSet) Delete(key []byte) error {
	db.lock.Lock()
	defer db.lock.Unlock()

	delete(db.nodes, string(key))
	return nil
}

func (db *ProofSet) DeleteRange(start, end []byte) error {
	panic("not supported")
}

// Get returns a stored node
func (db *ProofSet) Get(key []byte) ([]byte, error) {
	db.lock.RLock()
	defer db.lock.RUnlock()

	if entry, ok := db.nodes[string(key)]; ok {
		return entry, nil
	}
	return nil, errors.New("not found")
}

// Has returns true if the node set contains the given key
func (db *ProofSet) Has(key []byte) (bool, error) {
	_, err := db.Get(key)
	return err == nil, nil
}

View on GitHub (pinned to 6bb0588ad8)

Solutions

1. Check the call site: ProofSet must only be given to proof/range-proof verification functions, never to general storage code
2. Replace the ProofSet with a real memdb (e.g. ethdb.NewMemDatabase) if you genuinely need deletion support
3. If you forked the verification API and now need DeleteRange, implement it instead of panicking (delete by key range from the map)

Example fix

// before
set := trienode.NewProofSet()
trydb.Compact(set, start, end) // panics: DeleteRange not supported

// after
mem := rawdb.NewMemoryDatabase()
trydb.Compact(mem, start, end)

// Only hand ProofSet to read-collect verification APIs
var _ ethdb.KeyValueReader = (*trienode.ProofSet)(nil) // document the intent
// before generic calls:
if _, ok := db.(interface{ DeleteRange([]byte, []byte) error }); ok && !isProofAPI(callee) {
    db = rawdb.NewMemoryDatabase()
}

func isProofSet(db ethdb.Database) bool { _, ok := db.(*trienode.ProofSet); return ok }

When it happens

Trigger: Passing a *trienode.ProofSet as the ethdb.KeyValueWriter parameter of a function that performs range deletions (e.g. compaction helpers, trie iterator pruning, or any code path calling DeleteRange on its supplied database).

Common situations: Refactoring geth internals and accidentally routing a write-path database argument to proof verification; custom tools reusing ProofSet as a generic in-memory db; API changes where a proof callback signature gained writer methods.

Related errors

• not implemented
• duplicated flush operation
• unknown layer type: %T
• nil chainID
• error decoding contract deployer hex %s: %v

AI-assisted analysis of ethereum/go-ethereum@6bb0588ad8 (2026-08-15). Data as JSON: /api/errors/6166cea35356f7a7. Report an issue: GitHub.