[Bug other/78839] DWARF output different between GCC 5 and 6

[toconnor at forcepoint dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78839

--- Comment #6 from Tom O'Connor  ---
(In reply to Andrew Pinski from comment #5)
> (In reply to Tom O'Connor from comment #4)
> > Bitfields seemed to work fine in all GCC prior to 6, FWIW.  The same
> > attached source code when built with other GCCs prior to 6 generates
> > DW_AT_data_member_location = 0 for all the fields as expected.  Only 6 gets
> > some of the fields "wrong".
> 
> Maybe I am thinking big-endian :).

Ah, I've only observed this on little-endian, as that's the only place I've
looked.

[Bug other/78839] DWARF output different between GCC 5 and 6

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78839

--- Comment #5 from Andrew Pinski  ---
(In reply to Tom O'Connor from comment #4)
> Bitfields seemed to work fine in all GCC prior to 6, FWIW.  The same
> attached source code when built with other GCCs prior to 6 generates
> DW_AT_data_member_location = 0 for all the fields as expected.  Only 6 gets
> some of the fields "wrong".

Maybe I am thinking big-endian :).

[Bug other/78839] DWARF output different between GCC 5 and 6

[toconnor at forcepoint dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78839

--- Comment #4 from Tom O'Connor  ---
Bitfields seemed to work fine in all GCC prior to 6, FWIW.  The same attached
source code when built with other GCCs prior to 6 generates
DW_AT_data_member_location = 0 for all the fields as expected.  Only 6 gets
some of the fields "wrong".

[Bug other/78839] DWARF output different between GCC 5 and 6

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78839

--- Comment #3 from Andrew Pinski  ---
IIRC bitfield are broken for dwarf2/3 and there is another mechanism for them
for dwarf5.

[Bug other/78839] DWARF output different between GCC 5 and 6

[toconnor at forcepoint dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78839

--- Comment #2 from Tom O'Connor  ---
Created attachment 40355
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=40355=edit
debuginfo from a GCC 6.1.0 build of s.c

[Bug other/78839] DWARF output different between GCC 5 and 6

[toconnor at forcepoint dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78839

--- Comment #1 from Tom O'Connor  ---
Created attachment 40354
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=40354=edit
debuginfo from a GCC 5.4.0 build of s.c