What causes "%s exists with wrong content (have %q want %q)" in golang/go?

Clear the VCS cache: 'go clean -cache' or 'rm -rf $(go env GOMODCACHE)/cache/vcs'.

%s exists with wrong content (have %q want %q)

Error message

%s exists with wrong content (have %q want %q)

What it means

Thrown by codehost.WorkDir when the .info metadata file for a cached VCS checkout exists and the checkout directory exists, but the .info content (the key string 'type:name') does not match the computed key. This indicates the cache entry is stale, corrupted, or the hash function changed between go versions.

Source

Thrown at src/cmd/go/internal/modfetch/codehost/codehost.go:258

	lockfile = dir + ".lock"
	if buildX {
		fmt.Fprintf(xLog, "# lock %s\n", lockfile)
	}

	unlock, err := lockedfile.MutexAt(lockfile).Lock()
	if err != nil {
		return "", "", fmt.Errorf("codehost.WorkDir: can't find or create lock file: %v", err)
	}
	defer unlock()

	data, err := os.ReadFile(dir + ".info")
	info, err2 := os.Stat(dir)
	if err == nil && err2 == nil && info.IsDir() {
		// Info file and directory both already exist: reuse.
		have := strings.TrimSuffix(string(data), "\n")
		if have != key {
			return "", "", fmt.Errorf("%s exists with wrong content (have %q want %q)", dir+".info", have, key)
		}
		if buildX {
			fmt.Fprintf(xLog, "# %s for %s %s\n", dir, typ, name)
		}
		return dir, lockfile, nil
	}

	// Info file or directory missing. Start from scratch.
	if xLog != nil {
		fmt.Fprintf(xLog, "mkdir -p %s # %s %s\n", dir, typ, name)
	}
	os.RemoveAll(dir)
	if err := os.MkdirAll(dir, 0777); err != nil {
		return "", "", err
	}
	if err := os.WriteFile(dir+".info", []byte(key), 0666); err != nil {
		os.RemoveAll(dir)
		return "", "", err

View on GitHub (pinned to b6b368adc5)

Solutions

Clear the VCS cache: 'go clean -cache' or 'rm -rf $(go env GOMODCACHE)/cache/vcs'.
Retry the go command — it will re-clone fresh.
If recurring, check filesystem health (fsck/disk diagnostics).
Ensure only one go version writes to a given GOMODCACHE.

Example fix

# before: stale .info from old go version
$ go get example.com/mod
... exists with wrong content ...
# after
go clean -cache
go get example.com/mod

Defensive patterns

Strategy: fallback

Validate before calling

null

Type guard

null

Try / catch

null

Prevention

Use one go version per GOMODCACHE to avoid key-derivation mismatches.
Run 'go clean -cache' after major go version upgrades.
Don't manually edit files under GOMODCACHE/cache/vcs.
Don't copy cache directories between machines; let go rebuild them.

When it happens

Trigger: Accessing a cached VCS repo after upgrading go (the key derivation or directory layout changed), after manual tampering with the cache, or after a filesystem corruption event.

Common situations: Downgrading or upgrading across major go versions that changed the cache layout; running 'go clean -cache' partially; disk corruption; copying a cache between machines with different architectures where the hash input differs.

Related errors

AI-assisted analysis of golang/go@b6b368adc5 (2026-08-12). Data as JSON: /api/errors/a33907c8e59eda4a. Report an issue: GitHub.