Re: [Qemu-devel] [PATCH 1/7] Add new macro QEMU_PACKED for packed C structures

[Stefan Weil]

Am 28.08.2011 22:47, schrieb Andreas Färber:
> Am 28.08.2011 um 22:43 schrieb Stefan Weil:
>
> > A packed struct needs different gcc attributes for compilations
> > with MinGW compilers because glib-2.0 adds compiler flag
> > -mms-bitfields which modifies the packing algorithm.
>
> Is that algorithm actually needed anywhere? If not, is there no GCC 
> option to fix this centrally in configure for win32 only?
>
> Andreas

I think it is needed: glib-2.0 requires -mms-bitfields for MinGW which
breaks networking (and more) for w32 hosts because of changes
in struct alignment. A central solution would require removal of
-mms-bitfields or its effects. This is possible, but very risky,
because it will raise problems with glib-2.0 and w32 libraries.
Therefore a central solution was rejected.

See this thread:
http://lists.gnu.org/archive/html/qemu-devel/2011-08/msg01877.html

Stefan