Maybe I didn't understand your comments correctly.
I think this line should already answered your questions.
Note: There is no reference sign on a function call - only on function definitions.
If you meant to remove the sign on a function call, it is good to go. If you meant to remove it from the above lines which is function definition, it will definitely cause problems.
FYI, if you ever need to compile your own php.ini file, you can follow the instruction on this article.
I've already tried the above example with the default php.ini file provided by DH and it is working perfectly. I will suggest you to revise all your scripts and remove sign on function call.