Re: gdb can't print array element for fortran

[Jan Kratochvil <jan.kratochvil@redhat.com>]

On Mon, 15 Mar 2010 21:51:48 +0100, Tom Tromey wrote:
> Joel> I haven't looked at Jan's work for the Fortran VLA stuff in a while,
> Joel> so I can't remember how he dealt with this issue.  But I think his
> Joel> approach might be more correct.
> 
> I too have lost track of this, but my impression is that Jan's current
> patch is rather larger.

The VLA patch of mine does a real calculation of the dynamic sizes.  This
patch just considers dynamically-sized arrays as unbound.

This patch will be superseded by the VLA patch.  But I do not have the VLA
patch ready now in a suitable form for FSF GDB.  Fixed the Chandru's patch if
this partial functionality is enough on its own.

No regressions on {x86_64,x86_64-m32,i686}-fedora12-linux-gnu.  The
functionality is already tested by the testsuite so the patch does:
-FAIL: gdb.fortran/array-element.exp: print the first element of array a
+PASS: gdb.fortran/array-element.exp: print the first element of array a


Thanks,
Jan


2010-03-16  Jan Kratochvil  <jan.kratochvil@redhat.com>
	    Chandru <chandru@in.ibm.com>

	* dwarf2read.c (read_subrange_type): Set TYPE_HIGH_BOUND_UNDEFINED.
	* valarith.c (value_subscripted_rvalue): Suppress error if
	TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED.

--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -6074,6 +6074,9 @@ read_subrange_type (struct die_info *die, struct dwarf2_cu *cu)
 
   range_type = create_range_type (NULL, base_type, low, high);
 
+  if (attr && attr->form == DW_FORM_block1)
+    TYPE_HIGH_BOUND_UNDEFINED (range_type) = 1;
+
   name = dwarf2_name (die, cu);
   if (name)
     TYPE_NAME (range_type) = name;
--- a/gdb/valarith.c
+++ b/gdb/valarith.c
@@ -198,7 +198,8 @@ value_subscripted_rvalue (struct value *array, LONGEST index, int lowerbound)
   unsigned int elt_offs = elt_size * longest_to_int (index - lowerbound);
   struct value *v;
 
-  if (index < lowerbound || elt_offs >= TYPE_LENGTH (array_type))
+  if (index < lowerbound || (!TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (array_type)
+			     && elt_offs >= TYPE_LENGTH (array_type)))
     error (_("no such vector element"));
 
   v = allocate_value (elt_type);