Re: [sv-bc] ref variable initialization

>From: Surya Pratik Saha <spsaha@cal.interrasystems.com>

>If a ref variable initialized at the time of declaration, will it be treated as
>procedural assignment?
...
>What will be the behaviour for the following test case?
>module xx;
>     function int f(ref int x = 1);
>        return x;
>     endfunction

That is not an initializer.  That is a default argument value to be
passed if the caller does not supply one.

This code is also illegal.  A constant is not a legal value to pass by
reference, so this is not a legal default value for a ref argument.

There is no way to apply an initializer to a ref argument, so your
question doesn't make sense.

Also, a function with a ref argument must be automatic, so a ref
argument is always automatic.  This means that hierarchical references
to ref arguments are illegal.  So your reference to f.x is illegal.

As an automatic, the ref argument does not exist, and does not have a
value, before it is called.  When the function is called, the ref
argument is created and initialized to refer to the actual argument
passed.  That is the only way it is ever initialized.


Steven Sharp
sharp@cadence.com