调用函数不能用&

Deprecated function: Call-time pass-by-reference has been deprecated; If you would like to pass it by reference, modify the declaration of a(). If you would like to enable call-time pass-by-reference, you can set allow_call_time_pass_reference to true in your INI file indrupal_load() (line 1112 of D:\phpStudy\WWW\drupal7\includes\bootstrap.inc).

function a($abc){
   print $abc + 1;
}
function b(){
 $abc = ‘123‘;
 a(&$abc);
}