Allow_call_time_pass_reference directive allows you to enable and disable warnings which PHP will issue if you pass a value by reference at function call time.Passing values by reference at function call time is a deprecated feature which will be removed from PHP at some point in the near future.

This directive does not disable this feature, it only determines whether PHP will warn you about it or not. These warnings should enabled in development environments only.

allow_call_time_pass_reference = On | Off

; allow_call_time_pass_reference
; Default Value: On
; Development Value: Off
; Production Value: Off

Function arguments can be passed in two ways: by value and by reference. Exactly how each argument is passed to a function at function call time can be specified in the function definition, which is the recommended means for doing so.

However,you can force all arguments to be passed by reference at function call time by enabling allow_call_time_pass_reference.