[fortran, patch] Remove unused elements in array argument to set_options

[FX]

> Thinking out loud here.  I wonder, however, if we want
> to future proof the library against changes to the
> options passed by having a few spare unused entried 
> available.  This of course only helps if a new option
> needs to be added.  It does nothing for removal.

That’s actually the way gfortran_set_options() works, to ensure that we can add options in the future: in main() we allocate an array of values, and pass that array and its size to gfortran_set_options(). gfortran_set_options() then deals with the number of options passed, meaning if an older program calls a newer library, the runtime will simply use default values for all options there were not passed.

And when we remove options, we simply pass zero values in their stead — until we break the ABI, when we clean up everything.

Patch committed, thanks for reviewing.

FX