public class Repro {
    static int count(String... names) {
        return names.length;
    }

    public static void main(String[] args) {
        int n = count("a", "b");
        System.out.println(n);
    }
}

Exception in thread "main" java.lang.RuntimeException: 
Error while checking CtMethodImpl
  on main(String[] args) { 
  with 
Error while checking CtBlockImpl
  on { 
  with 
Error while checking CtLocalVariableImpl
  on n = count("a", "b"); 
  with 
Error while checking CtInvocationImpl
  on count("a", "b"); 
  with Index 1 out of bounds for length 1
Caused by: java.lang.RuntimeException: