Re: PATCH: Start Fortran support for variable objects.

[Daniel Jacobowitz <drow at false dot org>]

On Fri, Jul 01, 2005 at 04:32:54PM +1200, Nick Roberts wrote:
> So I should have done:
> 
> (top-gdb) p TYPE_LOW_BOUND(var->type->main_type->fields->type)
> $1 = 1
> (top-gdb) p TYPE_HIGH_BOUND(var->type->main_type->fields->type)
> $2 = 4

Right - specifically, TYPE_LOW_BOUND (TYPE_INDEX_TYPE (var->type))
is supposed to be the lower bound for an array.  Tricky.  It comes from
read_subrange_type in dwarf2read.c for dwarf2.

>  > I guess there might be some errors in the process of creating varobj for 
>  > Fortran array.  
> 
> No the information seems to be there.  So maybe:
> 
>   for (i = 0; i < var->num_children; i++)
>     {
>       /* Mark as the end in case we bail out */
>       *((*childlist) + i) = NULL;
> 
>       j = i + TYPE_LOW_BOUND(var->type->main_type->fields->type);
> 
>       /* check if child exists, if not create */
>       name = name_of_child (var, j);
>       child = child_exists (var, name);
>       if (child == NULL)
> 	child = create_child (var, j, name);
> 
>       *((*childlist) + i) = child;
>     }
> 
> will work in varobj_list_children in a language independent way.
> 
> I'll wait to see what Daniel says though, before submitting another patch.

First of all, never reference ->main_type - see above for the right way
to get the low bound.  An even better way (it seems) is to call
get_discrete_bounds.  Take a look at value_subscript for an example.

I can't tell what f77_get_dynamic_lowerbound is supposed to handle.
But it does a really, really good impression of reading data which is
no longer set anywhere, so I have the feeling that it is dead code.
Sorry for pointing you at it.

So let's use TYPE_LOW_BOUND for now; does that eliminate the need for
the fortran-specific code?

-- 
Daniel Jacobowitz
CodeSourcery, LLC