golang/go · error

leading slash

Error message

leading slash

What it means

validateRepoSubDir rejects a repository subdirectory that begins with `/`. Subdirs are expected to be relative paths within the repo; a leading slash would resolve outside the intended tree.

Source

Thrown at src/cmd/go/internal/vcs/vcs.go:1092

	rr := &RepoRoot{
		Repo:     repoURL,
		Root:     mmi.Prefix,
		SubDir:   mmi.SubDir,
		IsCustom: true,
		VCS:      vcs,
	}
	return rr, nil
}

// validateRepoSubDir returns an error if subdir is not a valid subdirectory path.
// We consider a subdirectory path to be valid as long as it doesn't have a leading
// slash (/) or hyphen (-).
func validateRepoSubDir(subdir string) error {
	if subdir == "" {
		return nil
	}
	if subdir[0] == '/' {
		return errors.New("leading slash")
	}
	if subdir[0] == '-' {
		return errors.New("leading hyphen")
	}
	return nil
}

// validateRepoRoot returns an error if repoRoot does not seem to be
// a valid URL with scheme.
func validateRepoRoot(repoRoot string) error {
	url, err := urlpkg.Parse(repoRoot)
	if err != nil {
		return err
	}
	if url.Scheme == "" {
		return errors.New("no scheme")
	}
	if url.Scheme == "file" {

View on GitHub (pinned to b6b368adc5)

Solutions

1. Fix the meta tag / vanity server to emit a relative subdir (no leading slash).
2. Drop the subdir component entirely if the repo root is correct.

Example fix

<!-- before -->
<meta name="go-import" content="example.com/git /sub/pkg git+ssh://...">
<!-- after -->
<meta name="go-import" content="example.com git+ssh://...">

// Validate a vanity subdir before publishing meta tags.
func validSubdir(s string) error {
    if strings.HasPrefix(s, "/") { return errors.New("subdir must be relative") }
    return nil
}

null

null

When it happens

Trigger: A vanity-import meta tag (or VCS path config) supplies a subdir like `/cmd/foo` instead of `cmd/foo`.

Common situations: Misconfigured `<meta name="go-import">`/`go-source` tags; hand-written vanity servers.

Related errors

• no scheme
• file scheme disallowed
• import path does not begin with hostname
• leading hyphen
• value is neither 'auto' nor a valid bool

AI-assisted analysis of golang/go@b6b368adc5 (2026-08-12). Data as JSON: /api/errors/47e8693323cb994a. Report an issue: GitHub.