// might inadvertently copy a lock by checking whether
// any of the range variables are locks.
func checkCopyLocksRange(pass *analysis.Pass, r *ast.RangeStmt) {
	checkCopyLocksRangeVar(pass, r.Tok, r.Key)
	checkCopyLocksRangeVar(pass, r.Tok, r.Value)
}

func checkCopyLocksRangeVar(pass *analysis.Pass, rtok token.Token, e ast.Expr) {
	if e == nil {
		return
	}
	id, isId := e.(*ast.Ident)
	if isId && id.Name == "_" {
		return