[C++ PATCH]: fix bug 143

[Nathan Sidwell]

Hi,
I've installed the attached patch and testcase which fixes bug 143.
When fishing out the FIELD_DECL of a vbase pointer, we'd forget that it
might be in a base at non-zero offset. Hence out type_info structures
could be hosed.

Approved by Mark, built & tested on i686-pc-linux-gnu

nathan
-- 
Dr Nathan Sidwell   ::   http://www.codesourcery.com   ::   CodeSourcery LLC
         'But that's a lie.' - 'Yes it is. What's your point?'
nathan@codesourcery.com : http://www.cs.bris.ac.uk/~nathan/ : nathan@acm.org
2000-06-20  Nathan Sidwell  <nathan@codesourcery.com>

	* rtti.c (get_base_offset): Cope when vbase field is in a base.

Index: cp/rtti.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/cp/rtti.c,v
retrieving revision 1.95
diff -c -3 -p -r1.95 rtti.c
*** rtti.c	2000/06/14 05:30:05	1.95
--- rtti.c	2000/06/20 12:18:05
*************** get_base_offset (binfo, parent)
*** 549,558 ****
    else if (! vbase_offsets_in_vtable_p ())
      {
        const char *name;
      
        FORMAT_VBASE_NAME (name, BINFO_TYPE (binfo));
!       return byte_position (lookup_field (parent, get_identifier (name),
! 					  0, 0));
      }
    else
      /* Under the new ABI, we store the vtable offset at which
--- 549,573 ----
    else if (! vbase_offsets_in_vtable_p ())
      {
        const char *name;
+       tree result;
+       tree field;
      
        FORMAT_VBASE_NAME (name, BINFO_TYPE (binfo));
!       field = lookup_field (parent, get_identifier (name), 0, 0);
!       result = byte_position (field);
!       
!       if (DECL_CONTEXT (field) != parent)
!         {
!           /* The vbase pointer might be in a non-virtual base of PARENT.
!            * Adjust for the offset of that base in PARENT.  */
!           tree path;
!           
!           get_base_distance (DECL_CONTEXT (field), parent, -1, &path);
!           result = build (PLUS_EXPR, TREE_TYPE (result),
!                           result, BINFO_OFFSET (path));
!           result = fold (result);
!         }
!       return result;
      }
    else
      /* Under the new ABI, we store the vtable offset at which