golangci/golangci-lint · error

failed to gob encode: %w

Error message

failed to gob encode: %w

What it means

Wrapping error in Cache.encode, called from Put: gob.NewEncoder(buf).Encode(data) failed while serializing cache data (typically an unencodable value type, unsupported field, or I/O error writing to the buffer). The raw gob error is wrapped with %w so the underlying cause is preserved; the cache write aborts.

Source

Thrown at internal/cache/cache.go:276

	h, err := cache.FileHash(f)

	<-c.ioSem

	if err != nil {
		return [cache.HashSize]byte{}, err
	}

	return h, nil
}

func (c *Cache) encode(data any) (*bytes.Buffer, error) {
	buf := &bytes.Buffer{}
	err := c.sw.TrackStageErr("gob", func() error {
		return gob.NewEncoder(buf).Encode(data)
	})
	if err != nil {
		return nil, fmt.Errorf("failed to gob encode: %w", err)
	}

	return buf, nil
}

func (c *Cache) decode(b []byte, data any) error {
	err := c.sw.TrackStageErr("gob", func() error {
		return gob.NewDecoder(bytes.NewReader(b)).Decode(data)
	})
	if err != nil {
		return fmt.Errorf("failed to gob decode: %w", err)
	}

	return nil
}

func SetSalt(b *bytes.Buffer) {
	cache.SetSalt(b.Bytes())

View on GitHub (pinned to ed7a235d2d)

Solutions

1. Inspect the wrapped gob error for the offending type or field
2. Ensure cached values contain only gob-encodable types (no funcs, channels, or unexported-only fields)
3. Clear a corrupted cache directory if the data format changed

When it happens

Trigger: Thrown at internal/cache/cache.go:276 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of golangci/golangci-lint@ed7a235d2d (2026-09-02). Data as JSON: /api/errors/569eeff4c92bab9e. Report an issue: GitHub.