[patch, fortran] use vec<> in frontend-passes.c

[Thomas Koenig]

Hi Tobias,

> first, thanks Trevor for the first round of review!

Also thanks from my side!


> I still see:
>> -  expr_count = 0;
>> +  expr_array.truncate (0);
> 
> Is there is a reason for not using release() here?

No, changed in the committed version.

Regards

	Thomas