[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 <toconnor at forcepoint dot com> ---
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".