golang/go · error

empty entry in GOVCS

Error message

empty entry in GOVCS

What it means

The GOVCS environment variable is a comma-separated list of 'pattern:vcsList' rules. During parsing, each comma-separated entry is trimmed; if an entry is empty (from a trailing comma, leading comma, or double comma), it is rejected as invalid.

Source

Thrown at src/cmd/go/internal/vcs/vcs.go:638

type govcsRule struct {
	pattern string
	allowed []string
}

// A govcsConfig is a full GOVCS configuration.
type govcsConfig []govcsRule

func parseGOVCS(s string) (govcsConfig, error) {
	s = strings.TrimSpace(s)
	if s == "" {
		return nil, nil
	}
	var cfg govcsConfig
	have := make(map[string]string)
	for item := range strings.SplitSeq(s, ",") {
		item = strings.TrimSpace(item)
		if item == "" {
			return nil, fmt.Errorf("empty entry in GOVCS")
		}
		pattern, list, found := strings.Cut(item, ":")
		if !found {
			return nil, fmt.Errorf("malformed entry in GOVCS (missing colon): %q", item)
		}
		pattern, list = strings.TrimSpace(pattern), strings.TrimSpace(list)
		if pattern == "" {
			return nil, fmt.Errorf("empty pattern in GOVCS: %q", item)
		}
		if list == "" {
			return nil, fmt.Errorf("empty VCS list in GOVCS: %q", item)
		}
		if search.IsRelativePath(pattern) {
			return nil, fmt.Errorf("relative pattern not allowed in GOVCS: %q", pattern)
		}
		if old := have[pattern]; old != "" {
			return nil, fmt.Errorf("unreachable pattern in GOVCS: %q after %q", item, old)
		}

View on GitHub (pinned to b6b368adc5)

Solutions

1. Inspect the full GOVCS value: `echo $GOVCS`
2. Remove stray/empty entries — every comma-separated item must be non-empty
3. Validate the GOVCS string before setting it (see validationCode)

Example fix

# before
export GOVCS="public:git,,private:all"

# after
export GOVCS="public:git,private:all"

# Validate GOVCS for empty entries before running go commands
GOVCS_VAL="${GOVCS:-}"
if [ -n "$GOVCS_VAL" ]; then
  echo "$GOVCS_VAL" | tr ',' '\n' | while IFS= read -r entry; do
    entry="$(echo "$entry" | xargs)"  # trim
    if [ -z "$entry" ]; then
      echo "ERROR: empty entry in GOVCS (check for stray/double/trailing commas)"
    fi
  done
fi

When it happens

Trigger: GOVCS contains a stray comma: `GOVCS=public:git,,private:all` (double comma) or `GOVCS=public:git,` (trailing comma) or `GOVCS=,public:git` (leading comma).

Common situations: Shell variable construction with empty elements; copy-paste errors in GOVCS; CI config templating that leaves trailing commas.

Related errors

• malformed entry in GOVCS (missing colon): %q
• empty pattern in GOVCS: %q
• empty VCS list in GOVCS: %q
• relative pattern not allowed in GOVCS: %q
• unreachable pattern in GOVCS: %q after %q

AI-assisted analysis of golang/go@b6b368adc5 (2026-08-12). Data as JSON: /api/errors/c73c5aa2290ef750. Report an issue: GitHub.