Cannot login to my drupal site because of php version 5.6
So finally I found that the problem is with php version 5.6 and workaround is:

function aikidolm_user_login(&amp;$edit, $account) {
  $_SESSION['aikidolm']['ulogged'] = 1; 
}


https://www.drupal.org/node/2363219#comment-9366567