}

var invalid = new(LabeledStmt) // singleton to signal invalid enclosing target

// enclosingTarget returns the innermost enclosing labeled statement matching
// the given name. The result is nil if the label is not defined, and invalid
// if the label is defined but doesn't label a valid labeled statement.
func (ls *labelScope) enclosingTarget(b *block, name string) *LabeledStmt {
	if l := ls.labels[name]; l != nil {