[Bug c/27948] New: MS -bitfield struct layout test fails

["dannysmith at users dot sourceforge dot net" <gcc-bugzilla at gcc dot gnu dot org>]

Since this revision:

2006-06-04 Eric Christopher <echristo@apple.com>

        * stor-layout.c (start_record_layout): Initialize
remaining_in_alignment.
        (debug_rli): Output value for remaining_in_alignment.
        (update_alignment_for_field): Unconditionalize
        ms_bitfield_layout_p code. Handle non-bitfield fields. Remove
        extra alignment code.
        (place_field): Don't realign if ms_bitfield_layout_p. Unconditionalize
        ms_bitfield_layout_p code. Rewrite handling of structure fields.
        * tree.h (record_layout_info_s): Remove prev_packed.
        * doc/extend.texi (ms_struct): Add documentation of format.


The ms-bitfield test gcc.dg/bf-ms-layout.c fails.

In particular, the 0-size bitfield  in
struct six { 
  char a :8;
  int :0;       /* not ignored; prior field IS a bitfield, causes
                   struct alignment as well. */
  char b;
  char c;
} ;

is being ignored

I have reconfirmed that that the test does indeed pass with MS VC6 compiler.

Danny


-- 
           Summary: MS -bitfield struct layout test fails
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: dannysmith at users dot sourceforge dot net
 GCC build triplet: i686-pc-mingw32
  GCC host triplet: i686-pc-mingw32
GCC target triplet: i686-pc-mingw32


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27948